diff --git a/TEST_MAPPING b/TEST_MAPPING
index a5b97a1..7fa5e7a 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -3,6 +3,10 @@
     {
       "name": "ConnectivityCoverageTests"
     },
+    {
+      // In addition to ConnectivityCoverageTests, runs non-connectivity-module tests
+      "name": "FrameworksNetTests"
+    },
     // Run in addition to mainline-presubmit as mainline-presubmit is not
     // supported in every branch.
     // CtsNetTestCasesLatestSdk uses stable API shims, so does not exercise
diff --git a/framework-t/Sources.bp b/framework-t/Sources.bp
new file mode 100644
index 0000000..53b4163
--- /dev/null
+++ b/framework-t/Sources.bp
@@ -0,0 +1,175 @@
+//
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// NetworkStats related libraries.
+
+filegroup {
+    name: "framework-connectivity-netstats-internal-sources",
+    srcs: [
+        "src/android/app/usage/*.java",
+        "src/android/net/DataUsageRequest.*",
+        "src/android/net/INetworkStatsService.aidl",
+        "src/android/net/INetworkStatsSession.aidl",
+        "src/android/net/NetworkIdentity.java",
+        "src/android/net/NetworkIdentitySet.java",
+        "src/android/net/NetworkStateSnapshot.*",
+        "src/android/net/NetworkStats.*",
+        "src/android/net/NetworkStatsAccess.*",
+        "src/android/net/NetworkStatsCollection.*",
+        "src/android/net/NetworkStatsHistory.*",
+        "src/android/net/NetworkTemplate.*",
+        "src/android/net/TrafficStats.java",
+        "src/android/net/UnderlyingNetworkInfo.*",
+        "src/android/net/netstats/**/*.*",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+filegroup {
+    name: "framework-connectivity-netstats-sources",
+    srcs: [
+        ":framework-connectivity-netstats-internal-sources",
+    ],
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// Nsd related libraries.
+
+filegroup {
+    name: "framework-connectivity-nsd-internal-sources",
+    srcs: [
+        "src/android/net/nsd/*.aidl",
+        "src/android/net/nsd/*.java",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+filegroup {
+    name: "framework-connectivity-nsd-sources",
+    srcs: [
+        ":framework-connectivity-nsd-internal-sources",
+    ],
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// IpSec related libraries.
+
+filegroup {
+    name: "framework-connectivity-ipsec-sources",
+    srcs: [
+        "src/android/net/IIpSecService.aidl",
+        "src/android/net/IpSec*.*",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// Ethernet related libraries.
+
+filegroup {
+    name: "framework-connectivity-ethernet-sources",
+    srcs: [
+        "src/android/net/EthernetManager.java",
+        "src/android/net/EthernetNetworkManagementException.java",
+        "src/android/net/EthernetNetworkManagementException.aidl",
+        "src/android/net/EthernetNetworkSpecifier.java",
+        "src/android/net/EthernetNetworkUpdateRequest.java",
+        "src/android/net/EthernetNetworkUpdateRequest.aidl",
+        "src/android/net/IEthernetManager.aidl",
+        "src/android/net/IEthernetServiceListener.aidl",
+        "src/android/net/INetworkInterfaceOutcomeReceiver.aidl",
+        "src/android/net/ITetheredInterfaceCallback.aidl",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// Connectivity-T common libraries.
+
+filegroup {
+    name: "framework-connectivity-tiramisu-internal-sources",
+    srcs: [
+        "src/android/net/ConnectivityFrameworkInitializerTiramisu.java",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// TODO: remove this empty filegroup.
+filegroup {
+    name: "framework-connectivity-tiramisu-sources",
+    srcs: [],
+    visibility: ["//frameworks/base"],
+}
+
+filegroup {
+    name: "framework-connectivity-tiramisu-updatable-sources",
+    srcs: [
+        ":framework-connectivity-ethernet-sources",
+        ":framework-connectivity-ipsec-sources",
+        ":framework-connectivity-netstats-sources",
+        ":framework-connectivity-nsd-sources",
+        ":framework-connectivity-tiramisu-internal-sources",
+    ],
+    visibility: [
+        "//frameworks/base",
+        "//packages/modules/Connectivity:__subpackages__",
+    ],
+}
+
+cc_library_shared {
+    name: "libframework-connectivity-tiramisu-jni",
+    min_sdk_version: "30",
+    cflags: [
+        "-Wall",
+        "-Werror",
+        "-Wno-unused-parameter",
+        // Don't warn about S API usage even with
+        // min_sdk 30: the library is only loaded
+        // on S+ devices
+        "-Wno-unguarded-availability",
+        "-Wthread-safety",
+    ],
+    srcs: [
+        "jni/android_net_TrafficStats.cpp",
+        "jni/onload.cpp",
+    ],
+    shared_libs: [
+        "libandroid",
+        "liblog",
+        "libnativehelper",
+    ],
+    stl: "none",
+    apex_available: [
+        "com.android.tethering",
+    ],
+}
diff --git a/framework-t/jni/android_net_TrafficStats.cpp b/framework-t/jni/android_net_TrafficStats.cpp
new file mode 100644
index 0000000..f3c58b1
--- /dev/null
+++ b/framework-t/jni/android_net_TrafficStats.cpp
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android/file_descriptor_jni.h>
+#include <android/multinetwork.h>
+#include <nativehelper/JNIHelp.h>
+
+namespace android {
+
+static jint tagSocketFd(JNIEnv* env, jclass, jobject fileDescriptor, jint tag, jint uid) {
+  int fd = AFileDescriptor_getFd(env, fileDescriptor);
+  if (fd == -1) return -EBADF;
+  return android_tag_socket_with_uid(fd, tag, uid);
+}
+
+static jint untagSocketFd(JNIEnv* env, jclass, jobject fileDescriptor) {
+  int fd = AFileDescriptor_getFd(env, fileDescriptor);
+  if (fd == -1) return -EBADF;
+  return android_untag_socket(fd);
+}
+
+static const JNINativeMethod gMethods[] = {
+    /* name, signature, funcPtr */
+    { "native_tagSocketFd", "(Ljava/io/FileDescriptor;II)I", (void*) tagSocketFd },
+    { "native_untagSocketFd", "(Ljava/io/FileDescriptor;)I", (void*) untagSocketFd },
+};
+
+int register_android_net_TrafficStats(JNIEnv* env) {
+    return jniRegisterNativeMethods(env, "android/net/TrafficStats", gMethods, NELEM(gMethods));
+}
+
+};  // namespace android
+
diff --git a/framework-t/jni/onload.cpp b/framework-t/jni/onload.cpp
new file mode 100644
index 0000000..1fb42c6
--- /dev/null
+++ b/framework-t/jni/onload.cpp
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "FrameworkConnectivityJNI"
+
+#include <log/log.h>
+#include <nativehelper/JNIHelp.h>
+
+namespace android {
+
+int register_android_net_TrafficStats(JNIEnv* env);
+
+extern "C" jint JNI_OnLoad(JavaVM* vm, void*) {
+    JNIEnv *env;
+    if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
+        __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, "ERROR: GetEnv failed");
+        return JNI_ERR;
+    }
+
+    if (register_android_net_TrafficStats(env) < 0) return JNI_ERR;
+
+    return JNI_VERSION_1_6;
+}
+
+};  // namespace android
+
diff --git a/framework-t/src/android/app/usage/NetworkStats.java b/framework-t/src/android/app/usage/NetworkStats.java
new file mode 100644
index 0000000..2b6570a
--- /dev/null
+++ b/framework-t/src/android/app/usage/NetworkStats.java
@@ -0,0 +1,742 @@
+/**
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.app.usage;
+
+import android.annotation.IntDef;
+import android.content.Context;
+import android.net.INetworkStatsService;
+import android.net.INetworkStatsSession;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.TrafficStats;
+import android.os.RemoteException;
+import android.util.Log;
+
+import com.android.net.module.util.CollectionUtils;
+
+import dalvik.system.CloseGuard;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayList;
+
+/**
+ * Class providing enumeration over buckets of network usage statistics. {@link NetworkStats} objects
+ * are returned as results to various queries in {@link NetworkStatsManager}.
+ */
+public final class NetworkStats implements AutoCloseable {
+    private final static String TAG = "NetworkStats";
+
+    private final CloseGuard mCloseGuard = CloseGuard.get();
+
+    /**
+     * Start timestamp of stats collected
+     */
+    private final long mStartTimeStamp;
+
+    /**
+     * End timestamp of stats collected
+     */
+    private final long mEndTimeStamp;
+
+    /**
+     * Non-null array indicates the query enumerates over uids.
+     */
+    private int[] mUids;
+
+    /**
+     * Index of the current uid in mUids when doing uid enumeration or a single uid value,
+     * depending on query type.
+     */
+    private int mUidOrUidIndex;
+
+    /**
+     * Tag id in case if was specified in the query.
+     */
+    private int mTag = android.net.NetworkStats.TAG_NONE;
+
+    /**
+     * State in case it was not specified in the query.
+     */
+    private int mState = Bucket.STATE_ALL;
+
+    /**
+     * The session while the query requires it, null if all the stats have been collected or close()
+     * has been called.
+     */
+    private INetworkStatsSession mSession;
+    private NetworkTemplate mTemplate;
+
+    /**
+     * Results of a summary query.
+     */
+    private android.net.NetworkStats mSummary = null;
+
+    /**
+     * Results of detail queries.
+     */
+    private NetworkStatsHistory mHistory = null;
+
+    /**
+     * Where we are in enumerating over the current result.
+     */
+    private int mEnumerationIndex = 0;
+
+    /**
+     * Recycling entry objects to prevent heap fragmentation.
+     */
+    private android.net.NetworkStats.Entry mRecycledSummaryEntry = null;
+    private NetworkStatsHistory.Entry mRecycledHistoryEntry = null;
+
+    /** @hide */
+    NetworkStats(Context context, NetworkTemplate template, int flags, long startTimestamp,
+            long endTimestamp, INetworkStatsService statsService)
+            throws RemoteException, SecurityException {
+        // Open network stats session
+        mSession = statsService.openSessionForUsageStats(flags, context.getOpPackageName());
+        mCloseGuard.open("close");
+        mTemplate = template;
+        mStartTimeStamp = startTimestamp;
+        mEndTimeStamp = endTimestamp;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        try {
+            if (mCloseGuard != null) {
+                mCloseGuard.warnIfOpen();
+            }
+            close();
+        } finally {
+            super.finalize();
+        }
+    }
+
+    // -------------------------BEGINNING OF PUBLIC API-----------------------------------
+
+    /**
+     * Buckets are the smallest elements of a query result. As some dimensions of a result may be
+     * aggregated (e.g. time or state) some values may be equal across all buckets.
+     */
+    public static class Bucket {
+        /** @hide */
+        @IntDef(prefix = { "STATE_" }, value = {
+                STATE_ALL,
+                STATE_DEFAULT,
+                STATE_FOREGROUND
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface State {}
+
+        /**
+         * Combined usage across all states.
+         */
+        public static final int STATE_ALL = -1;
+
+        /**
+         * Usage not accounted for in any other state.
+         */
+        public static final int STATE_DEFAULT = 0x1;
+
+        /**
+         * Foreground usage.
+         */
+        public static final int STATE_FOREGROUND = 0x2;
+
+        /**
+         * Special UID value for aggregate/unspecified.
+         */
+        public static final int UID_ALL = android.net.NetworkStats.UID_ALL;
+
+        /**
+         * Special UID value for removed apps.
+         */
+        public static final int UID_REMOVED = TrafficStats.UID_REMOVED;
+
+        /**
+         * Special UID value for data usage by tethering.
+         */
+        public static final int UID_TETHERING = TrafficStats.UID_TETHERING;
+
+        /** @hide */
+        @IntDef(prefix = { "METERED_" }, value = {
+                METERED_ALL,
+                METERED_NO,
+                METERED_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface Metered {}
+
+        /**
+         * Combined usage across all metered states. Covers metered and unmetered usage.
+         */
+        public static final int METERED_ALL = -1;
+
+        /**
+         * Usage that occurs on an unmetered network.
+         */
+        public static final int METERED_NO = 0x1;
+
+        /**
+         * Usage that occurs on a metered network.
+         *
+         * <p>A network is classified as metered when the user is sensitive to heavy data usage on
+         * that connection.
+         */
+        public static final int METERED_YES = 0x2;
+
+        /** @hide */
+        @IntDef(prefix = { "ROAMING_" }, value = {
+                ROAMING_ALL,
+                ROAMING_NO,
+                ROAMING_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface Roaming {}
+
+        /**
+         * Combined usage across all roaming states. Covers both roaming and non-roaming usage.
+         */
+        public static final int ROAMING_ALL = -1;
+
+        /**
+         * Usage that occurs on a home, non-roaming network.
+         *
+         * <p>Any cellular usage in this bucket was incurred while the device was connected to a
+         * tower owned or operated by the user's wireless carrier, or a tower that the user's
+         * wireless carrier has indicated should be treated as a home network regardless.
+         *
+         * <p>This is also the default value for network types that do not support roaming.
+         */
+        public static final int ROAMING_NO = 0x1;
+
+        /**
+         * Usage that occurs on a roaming network.
+         *
+         * <p>Any cellular usage in this bucket as incurred while the device was roaming on another
+         * carrier's network, for which additional charges may apply.
+         */
+        public static final int ROAMING_YES = 0x2;
+
+        /** @hide */
+        @IntDef(prefix = { "DEFAULT_NETWORK_" }, value = {
+                DEFAULT_NETWORK_ALL,
+                DEFAULT_NETWORK_NO,
+                DEFAULT_NETWORK_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface DefaultNetworkStatus {}
+
+        /**
+         * Combined usage for this network regardless of default network status.
+         */
+        public static final int DEFAULT_NETWORK_ALL = -1;
+
+        /**
+         * Usage that occurs while this network is not a default network.
+         *
+         * <p>This implies that the app responsible for this usage requested that it occur on a
+         * specific network different from the one(s) the system would have selected for it.
+         */
+        public static final int DEFAULT_NETWORK_NO = 0x1;
+
+        /**
+         * Usage that occurs while this network is a default network.
+         *
+         * <p>This implies that the app either did not select a specific network for this usage,
+         * or it selected a network that the system could have selected for app traffic.
+         */
+        public static final int DEFAULT_NETWORK_YES = 0x2;
+
+        /**
+         * Special TAG value for total data across all tags
+         */
+        public static final int TAG_NONE = android.net.NetworkStats.TAG_NONE;
+
+        private int mUid;
+        private int mTag;
+        private int mState;
+        private int mDefaultNetworkStatus;
+        private int mMetered;
+        private int mRoaming;
+        private long mBeginTimeStamp;
+        private long mEndTimeStamp;
+        private long mRxBytes;
+        private long mRxPackets;
+        private long mTxBytes;
+        private long mTxPackets;
+
+        private static int convertSet(@State int state) {
+            switch (state) {
+                case STATE_ALL: return android.net.NetworkStats.SET_ALL;
+                case STATE_DEFAULT: return android.net.NetworkStats.SET_DEFAULT;
+                case STATE_FOREGROUND: return android.net.NetworkStats.SET_FOREGROUND;
+            }
+            return 0;
+        }
+
+        private static @State int convertState(int networkStatsSet) {
+            switch (networkStatsSet) {
+                case android.net.NetworkStats.SET_ALL : return STATE_ALL;
+                case android.net.NetworkStats.SET_DEFAULT : return STATE_DEFAULT;
+                case android.net.NetworkStats.SET_FOREGROUND : return STATE_FOREGROUND;
+            }
+            return 0;
+        }
+
+        private static int convertUid(int uid) {
+            switch (uid) {
+                case TrafficStats.UID_REMOVED: return UID_REMOVED;
+                case TrafficStats.UID_TETHERING: return UID_TETHERING;
+            }
+            return uid;
+        }
+
+        private static int convertTag(int tag) {
+            switch (tag) {
+                case android.net.NetworkStats.TAG_NONE: return TAG_NONE;
+            }
+            return tag;
+        }
+
+        private static @Metered int convertMetered(int metered) {
+            switch (metered) {
+                case android.net.NetworkStats.METERED_ALL : return METERED_ALL;
+                case android.net.NetworkStats.METERED_NO: return METERED_NO;
+                case android.net.NetworkStats.METERED_YES: return METERED_YES;
+            }
+            return 0;
+        }
+
+        private static @Roaming int convertRoaming(int roaming) {
+            switch (roaming) {
+                case android.net.NetworkStats.ROAMING_ALL : return ROAMING_ALL;
+                case android.net.NetworkStats.ROAMING_NO: return ROAMING_NO;
+                case android.net.NetworkStats.ROAMING_YES: return ROAMING_YES;
+            }
+            return 0;
+        }
+
+        private static @DefaultNetworkStatus int convertDefaultNetworkStatus(
+                int defaultNetworkStatus) {
+            switch (defaultNetworkStatus) {
+                case android.net.NetworkStats.DEFAULT_NETWORK_ALL : return DEFAULT_NETWORK_ALL;
+                case android.net.NetworkStats.DEFAULT_NETWORK_NO: return DEFAULT_NETWORK_NO;
+                case android.net.NetworkStats.DEFAULT_NETWORK_YES: return DEFAULT_NETWORK_YES;
+            }
+            return 0;
+        }
+
+        public Bucket() {
+        }
+
+        /**
+         * Key of the bucket. Usually an app uid or one of the following special values:<p />
+         * <ul>
+         * <li>{@link #UID_REMOVED}</li>
+         * <li>{@link #UID_TETHERING}</li>
+         * <li>{@link android.os.Process#SYSTEM_UID}</li>
+         * </ul>
+         * @return Bucket key.
+         */
+        public int getUid() {
+            return mUid;
+        }
+
+        /**
+         * Tag of the bucket.<p />
+         * @return Bucket tag.
+         */
+        public int getTag() {
+            return mTag;
+        }
+
+        /**
+         * Usage state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #STATE_ALL}</li>
+         * <li>{@link #STATE_DEFAULT}</li>
+         * <li>{@link #STATE_FOREGROUND}</li>
+         * </ul>
+         * @return Usage state.
+         */
+        public @State int getState() {
+            return mState;
+        }
+
+        /**
+         * Metered state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #METERED_ALL}</li>
+         * <li>{@link #METERED_NO}</li>
+         * <li>{@link #METERED_YES}</li>
+         * </ul>
+         * <p>A network is classified as metered when the user is sensitive to heavy data usage on
+         * that connection. Apps may warn before using these networks for large downloads. The
+         * metered state can be set by the user within data usage network restrictions.
+         */
+        public @Metered int getMetered() {
+            return mMetered;
+        }
+
+        /**
+         * Roaming state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #ROAMING_ALL}</li>
+         * <li>{@link #ROAMING_NO}</li>
+         * <li>{@link #ROAMING_YES}</li>
+         * </ul>
+         */
+        public @Roaming int getRoaming() {
+            return mRoaming;
+        }
+
+        /**
+         * Default network status. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #DEFAULT_NETWORK_ALL}</li>
+         * <li>{@link #DEFAULT_NETWORK_NO}</li>
+         * <li>{@link #DEFAULT_NETWORK_YES}</li>
+         * </ul>
+         */
+        public @DefaultNetworkStatus int getDefaultNetworkStatus() {
+            return mDefaultNetworkStatus;
+        }
+
+        /**
+         * Start timestamp of the bucket's time interval. Defined in terms of "Unix time", see
+         * {@link java.lang.System#currentTimeMillis}.
+         * @return Start of interval.
+         */
+        public long getStartTimeStamp() {
+            return mBeginTimeStamp;
+        }
+
+        /**
+         * End timestamp of the bucket's time interval. Defined in terms of "Unix time", see
+         * {@link java.lang.System#currentTimeMillis}.
+         * @return End of interval.
+         */
+        public long getEndTimeStamp() {
+            return mEndTimeStamp;
+        }
+
+        /**
+         * Number of bytes received during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of bytes.
+         */
+        public long getRxBytes() {
+            return mRxBytes;
+        }
+
+        /**
+         * Number of bytes transmitted during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of bytes.
+         */
+        public long getTxBytes() {
+            return mTxBytes;
+        }
+
+        /**
+         * Number of packets received during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of packets.
+         */
+        public long getRxPackets() {
+            return mRxPackets;
+        }
+
+        /**
+         * Number of packets transmitted during the bucket's time interval. Statistics are measured
+         * at the network layer, so they include both TCP and UDP usage.
+         * @return Number of packets.
+         */
+        public long getTxPackets() {
+            return mTxPackets;
+        }
+    }
+
+    /**
+     * Fills the recycled bucket with data of the next bin in the enumeration.
+     * @param bucketOut Bucket to be filled with data.
+     * @return true if successfully filled the bucket, false otherwise.
+     */
+    public boolean getNextBucket(Bucket bucketOut) {
+        if (mSummary != null) {
+            return getNextSummaryBucket(bucketOut);
+        } else {
+            return getNextHistoryBucket(bucketOut);
+        }
+    }
+
+    /**
+     * Check if it is possible to ask for a next bucket in the enumeration.
+     * @return true if there is at least one more bucket.
+     */
+    public boolean hasNextBucket() {
+        if (mSummary != null) {
+            return mEnumerationIndex < mSummary.size();
+        } else if (mHistory != null) {
+            return mEnumerationIndex < mHistory.size()
+                    || hasNextUid();
+        }
+        return false;
+    }
+
+    /**
+     * Closes the enumeration. Call this method before this object gets out of scope.
+     */
+    @Override
+    public void close() {
+        if (mSession != null) {
+            try {
+                mSession.close();
+            } catch (RemoteException e) {
+                Log.w(TAG, e);
+                // Otherwise, meh
+            }
+        }
+        mSession = null;
+        if (mCloseGuard != null) {
+            mCloseGuard.close();
+        }
+    }
+
+    // -------------------------END OF PUBLIC API-----------------------------------
+
+    /**
+     * Collects device summary results into a Bucket.
+     * @throws RemoteException
+     */
+    Bucket getDeviceSummaryForNetwork() throws RemoteException {
+        mSummary = mSession.getDeviceSummaryForNetwork(mTemplate, mStartTimeStamp, mEndTimeStamp);
+
+        // Setting enumeration index beyond end to avoid accidental enumeration over data that does
+        // not belong to the calling user.
+        mEnumerationIndex = mSummary.size();
+
+        return getSummaryAggregate();
+    }
+
+    /**
+     * Collects summary results and sets summary enumeration mode.
+     * @throws RemoteException
+     */
+    void startSummaryEnumeration() throws RemoteException {
+        mSummary = mSession.getSummaryForAllUid(mTemplate, mStartTimeStamp, mEndTimeStamp,
+                false /* includeTags */);
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Collects tagged summary results and sets summary enumeration mode.
+     * @throws RemoteException
+     */
+    void startTaggedSummaryEnumeration() throws RemoteException {
+        mSummary = mSession.getTaggedSummaryForAllUid(mTemplate, mStartTimeStamp, mEndTimeStamp);
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Collects history results for uid and resets history enumeration index.
+     */
+    void startHistoryUidEnumeration(int uid, int tag, int state) {
+        mHistory = null;
+        try {
+            mHistory = mSession.getHistoryIntervalForUid(mTemplate, uid,
+                    Bucket.convertSet(state), tag, NetworkStatsHistory.FIELD_ALL,
+                    mStartTimeStamp, mEndTimeStamp);
+            setSingleUidTagState(uid, tag, state);
+        } catch (RemoteException e) {
+            Log.w(TAG, e);
+            // Leaving mHistory null
+        }
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Collects history results for network and resets history enumeration index.
+     */
+    void startHistoryDeviceEnumeration() {
+        try {
+            mHistory = mSession.getHistoryIntervalForNetwork(
+                    mTemplate, NetworkStatsHistory.FIELD_ALL, mStartTimeStamp, mEndTimeStamp);
+        } catch (RemoteException e) {
+            Log.w(TAG, e);
+            mHistory = null;
+        }
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Starts uid enumeration for current user.
+     * @throws RemoteException
+     */
+    void startUserUidEnumeration() throws RemoteException {
+        // TODO: getRelevantUids should be sensitive to time interval. When that's done,
+        //       the filtering logic below can be removed.
+        int[] uids = mSession.getRelevantUids();
+        // Filtering of uids with empty history.
+        final ArrayList<Integer> filteredUids = new ArrayList<>();
+        for (int uid : uids) {
+            try {
+                NetworkStatsHistory history = mSession.getHistoryIntervalForUid(mTemplate, uid,
+                        android.net.NetworkStats.SET_ALL, android.net.NetworkStats.TAG_NONE,
+                        NetworkStatsHistory.FIELD_ALL, mStartTimeStamp, mEndTimeStamp);
+                if (history != null && history.size() > 0) {
+                    filteredUids.add(uid);
+                }
+            } catch (RemoteException e) {
+                Log.w(TAG, "Error while getting history of uid " + uid, e);
+            }
+        }
+        mUids = CollectionUtils.toIntArray(filteredUids);
+        mUidOrUidIndex = -1;
+        stepHistory();
+    }
+
+    /**
+     * Steps to next uid in enumeration and collects history for that.
+     */
+    private void stepHistory(){
+        if (hasNextUid()) {
+            stepUid();
+            mHistory = null;
+            try {
+                mHistory = mSession.getHistoryIntervalForUid(mTemplate, getUid(),
+                        android.net.NetworkStats.SET_ALL, android.net.NetworkStats.TAG_NONE,
+                        NetworkStatsHistory.FIELD_ALL, mStartTimeStamp, mEndTimeStamp);
+            } catch (RemoteException e) {
+                Log.w(TAG, e);
+                // Leaving mHistory null
+            }
+            mEnumerationIndex = 0;
+        }
+    }
+
+    private void fillBucketFromSummaryEntry(Bucket bucketOut) {
+        bucketOut.mUid = Bucket.convertUid(mRecycledSummaryEntry.uid);
+        bucketOut.mTag = Bucket.convertTag(mRecycledSummaryEntry.tag);
+        bucketOut.mState = Bucket.convertState(mRecycledSummaryEntry.set);
+        bucketOut.mDefaultNetworkStatus = Bucket.convertDefaultNetworkStatus(
+                mRecycledSummaryEntry.defaultNetwork);
+        bucketOut.mMetered = Bucket.convertMetered(mRecycledSummaryEntry.metered);
+        bucketOut.mRoaming = Bucket.convertRoaming(mRecycledSummaryEntry.roaming);
+        bucketOut.mBeginTimeStamp = mStartTimeStamp;
+        bucketOut.mEndTimeStamp = mEndTimeStamp;
+        bucketOut.mRxBytes = mRecycledSummaryEntry.rxBytes;
+        bucketOut.mRxPackets = mRecycledSummaryEntry.rxPackets;
+        bucketOut.mTxBytes = mRecycledSummaryEntry.txBytes;
+        bucketOut.mTxPackets = mRecycledSummaryEntry.txPackets;
+    }
+
+    /**
+     * Getting the next item in summary enumeration.
+     * @param bucketOut Next item will be set here.
+     * @return true if a next item could be set.
+     */
+    private boolean getNextSummaryBucket(Bucket bucketOut) {
+        if (bucketOut != null && mEnumerationIndex < mSummary.size()) {
+            mRecycledSummaryEntry = mSummary.getValues(mEnumerationIndex++, mRecycledSummaryEntry);
+            fillBucketFromSummaryEntry(bucketOut);
+            return true;
+        }
+        return false;
+    }
+
+    Bucket getSummaryAggregate() {
+        if (mSummary == null) {
+            return null;
+        }
+        Bucket bucket = new Bucket();
+        if (mRecycledSummaryEntry == null) {
+            mRecycledSummaryEntry = new android.net.NetworkStats.Entry();
+        }
+        mSummary.getTotal(mRecycledSummaryEntry);
+        fillBucketFromSummaryEntry(bucket);
+        return bucket;
+    }
+
+    /**
+     * Getting the next item in a history enumeration.
+     * @param bucketOut Next item will be set here.
+     * @return true if a next item could be set.
+     */
+    private boolean getNextHistoryBucket(Bucket bucketOut) {
+        if (bucketOut != null && mHistory != null) {
+            if (mEnumerationIndex < mHistory.size()) {
+                mRecycledHistoryEntry = mHistory.getValues(mEnumerationIndex++,
+                        mRecycledHistoryEntry);
+                bucketOut.mUid = Bucket.convertUid(getUid());
+                bucketOut.mTag = Bucket.convertTag(mTag);
+                bucketOut.mState = mState;
+                bucketOut.mDefaultNetworkStatus = Bucket.DEFAULT_NETWORK_ALL;
+                bucketOut.mMetered = Bucket.METERED_ALL;
+                bucketOut.mRoaming = Bucket.ROAMING_ALL;
+                bucketOut.mBeginTimeStamp = mRecycledHistoryEntry.bucketStart;
+                bucketOut.mEndTimeStamp = mRecycledHistoryEntry.bucketStart +
+                        mRecycledHistoryEntry.bucketDuration;
+                bucketOut.mRxBytes = mRecycledHistoryEntry.rxBytes;
+                bucketOut.mRxPackets = mRecycledHistoryEntry.rxPackets;
+                bucketOut.mTxBytes = mRecycledHistoryEntry.txBytes;
+                bucketOut.mTxPackets = mRecycledHistoryEntry.txPackets;
+                return true;
+            } else if (hasNextUid()) {
+                stepHistory();
+                return getNextHistoryBucket(bucketOut);
+            }
+        }
+        return false;
+    }
+
+    // ------------------ UID LOGIC------------------------
+
+    private boolean isUidEnumeration() {
+        return mUids != null;
+    }
+
+    private boolean hasNextUid() {
+        return isUidEnumeration() && (mUidOrUidIndex + 1) < mUids.length;
+    }
+
+    private int getUid() {
+        // Check if uid enumeration.
+        if (isUidEnumeration()) {
+            if (mUidOrUidIndex < 0 || mUidOrUidIndex >= mUids.length) {
+                throw new IndexOutOfBoundsException(
+                        "Index=" + mUidOrUidIndex + " mUids.length=" + mUids.length);
+            }
+            return mUids[mUidOrUidIndex];
+        }
+        // Single uid mode.
+        return mUidOrUidIndex;
+    }
+
+    private void setSingleUidTagState(int uid, int tag, int state) {
+        mUidOrUidIndex = uid;
+        mTag = tag;
+        mState = state;
+    }
+
+    private void stepUid() {
+        if (mUids != null) {
+            ++mUidOrUidIndex;
+        }
+    }
+}
diff --git a/framework-t/src/android/app/usage/NetworkStatsManager.java b/framework-t/src/android/app/usage/NetworkStatsManager.java
new file mode 100644
index 0000000..bf518b2
--- /dev/null
+++ b/framework-t/src/android/app/usage/NetworkStatsManager.java
@@ -0,0 +1,1181 @@
+/**
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.app.usage;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
+import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
+
+import android.Manifest;
+import android.annotation.CallbackExecutor;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
+import android.annotation.SystemService;
+import android.annotation.WorkerThread;
+import android.app.usage.NetworkStats.Bucket;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.DataUsageRequest;
+import android.net.INetworkStatsService;
+import android.net.Network;
+import android.net.NetworkStack;
+import android.net.NetworkStateSnapshot;
+import android.net.NetworkTemplate;
+import android.net.UnderlyingNetworkInfo;
+import android.net.netstats.IUsageCallback;
+import android.net.netstats.NetworkStatsDataMigrationUtils;
+import android.net.netstats.provider.INetworkStatsProviderCallback;
+import android.net.netstats.provider.NetworkStatsProvider;
+import android.os.Build;
+import android.os.Handler;
+import android.os.RemoteException;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.Executor;
+
+/**
+ * Provides access to network usage history and statistics. Usage data is collected in
+ * discrete bins of time called 'Buckets'. See {@link NetworkStats.Bucket} for details.
+ * <p />
+ * Queries can define a time interval in the form of start and end timestamps (Long.MIN_VALUE and
+ * Long.MAX_VALUE can be used to simulate open ended intervals). By default, apps can only obtain
+ * data about themselves. See the below note for special cases in which apps can obtain data about
+ * other applications.
+ * <h3>
+ * Summary queries
+ * </h3>
+ * {@link #querySummaryForDevice} <p />
+ * {@link #querySummaryForUser} <p />
+ * {@link #querySummary} <p />
+ * These queries aggregate network usage across the whole interval. Therefore there will be only one
+ * bucket for a particular key, state, metered and roaming combination. In case of the user-wide
+ * and device-wide summaries a single bucket containing the totalised network usage is returned.
+ * <h3>
+ * History queries
+ * </h3>
+ * {@link #queryDetailsForUid} <p />
+ * {@link #queryDetails} <p />
+ * These queries do not aggregate over time but do aggregate over state, metered and roaming.
+ * Therefore there can be multiple buckets for a particular key. However, all Buckets will have
+ * {@code state} {@link NetworkStats.Bucket#STATE_ALL},
+ * {@code defaultNetwork} {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+ * {@code metered } {@link NetworkStats.Bucket#METERED_ALL},
+ * {@code roaming} {@link NetworkStats.Bucket#ROAMING_ALL}.
+ * <p />
+ * <b>NOTE:</b> Calling {@link #querySummaryForDevice} or accessing stats for apps other than the
+ * calling app requires the permission {@link android.Manifest.permission#PACKAGE_USAGE_STATS},
+ * which is a system-level permission and will not be granted to third-party apps. However,
+ * declaring the permission implies intention to use the API and the user of the device can grant
+ * permission through the Settings application.
+ * <p />
+ * Profile owner apps are automatically granted permission to query data on the profile they manage
+ * (that is, for any query except {@link #querySummaryForDevice}). Device owner apps and carrier-
+ * privileged apps likewise get access to usage data for all users on the device.
+ * <p />
+ * In addition to tethering usage, usage by removed users and apps, and usage by the system
+ * is also included in the results for callers with one of these higher levels of access.
+ * <p />
+ * <b>NOTE:</b> Prior to API level {@value android.os.Build.VERSION_CODES#N}, all calls to these APIs required
+ * the above permission, even to access an app's own data usage, and carrier-privileged apps were
+ * not included.
+ */
+@SystemService(Context.NETWORK_STATS_SERVICE)
+public class NetworkStatsManager {
+    private static final String TAG = "NetworkStatsManager";
+    private static final boolean DBG = false;
+
+    /** @hide */
+    public static final int CALLBACK_LIMIT_REACHED = 0;
+    /** @hide */
+    public static final int CALLBACK_RELEASED = 1;
+
+    /**
+     * Minimum data usage threshold for registering usage callbacks.
+     *
+     * Requests registered with a threshold lower than this will only be triggered once this minimum
+     * is reached.
+     * @hide
+     */
+    public static final long MIN_THRESHOLD_BYTES = 2 * 1_048_576L; // 2MiB
+
+    private final Context mContext;
+    private final INetworkStatsService mService;
+
+    /**
+     * @deprecated Use {@link NetworkStatsDataMigrationUtils#PREFIX_XT}
+     * instead.
+     * @hide
+     */
+    @Deprecated
+    public static final String PREFIX_DEV = "dev";
+
+    /** @hide */
+    public static final int FLAG_POLL_ON_OPEN = 1 << 0;
+    /** @hide */
+    public static final int FLAG_POLL_FORCE = 1 << 1;
+    /** @hide */
+    public static final int FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN = 1 << 2;
+
+    /**
+     * Virtual RAT type to represent 5G NSA (Non Stand Alone) mode, where the primary cell is
+     * still LTE and network allocates a secondary 5G cell so telephony reports RAT = LTE along
+     * with NR state as connected. This is a concept added by NetworkStats on top of the telephony
+     * constants for backward compatibility of metrics so this should not be overlapped with any of
+     * the {@code TelephonyManager.NETWORK_TYPE_*} constants.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int NETWORK_TYPE_5G_NSA = -2;
+
+    private int mFlags;
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStatsManager(Context context, INetworkStatsService service) {
+        mContext = context;
+        mService = service;
+        setPollOnOpen(true);
+        setAugmentWithSubscriptionPlan(true);
+    }
+
+    /** @hide */
+    public INetworkStatsService getBinder() {
+        return mService;
+    }
+
+    /**
+     * Set poll on open flag to indicate the poll is needed before service gets statistics
+     * result. This is default enabled. However, for any non-privileged caller, the poll might
+     * be omitted in case of rate limiting.
+     *
+     * @param pollOnOpen true if poll is needed.
+     * @hide
+     */
+    // The system will ignore any non-default values for non-privileged
+    // processes, so processes that don't hold the appropriate permissions
+    // can make no use of this API.
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void setPollOnOpen(boolean pollOnOpen) {
+        if (pollOnOpen) {
+            mFlags |= FLAG_POLL_ON_OPEN;
+        } else {
+            mFlags &= ~FLAG_POLL_ON_OPEN;
+        }
+    }
+
+    /**
+     * Set poll force flag to indicate that calling any subsequent query method will force a stats
+     * poll.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void setPollForce(boolean pollForce) {
+        if (pollForce) {
+            mFlags |= FLAG_POLL_FORCE;
+        } else {
+            mFlags &= ~FLAG_POLL_FORCE;
+        }
+    }
+
+    /** @hide */
+    public void setAugmentWithSubscriptionPlan(boolean augmentWithSubscriptionPlan) {
+        if (augmentWithSubscriptionPlan) {
+            mFlags |= FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN;
+        } else {
+            mFlags &= ~FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN;
+        }
+    }
+
+    /**
+     * Query network usage statistics summaries.
+     *
+     * Result is summarised data usage for the whole
+     * device. Result is a single Bucket aggregated over time, state, uid, tag, metered, and
+     * roaming. This means the bucket's start and end timestamp will be the same as the
+     * 'startTime' and 'endTime' arguments. State is going to be
+     * {@link NetworkStats.Bucket#STATE_ALL}, uid {@link NetworkStats.Bucket#UID_ALL},
+     * tag {@link NetworkStats.Bucket#TAG_NONE},
+     * default network {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered {@link NetworkStats.Bucket#METERED_ALL},
+     * and roaming {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param startTime Start of period, in milliseconds since the Unix epoch, see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period, in milliseconds since the Unix epoch, see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Bucket Summarised data usage.
+     *
+     * @hide
+     */
+    @NonNull
+    @WorkerThread
+    @SystemApi(client = MODULE_LIBRARIES)
+    public Bucket querySummaryForDevice(@NonNull NetworkTemplate template,
+            long startTime, long endTime) {
+        Objects.requireNonNull(template);
+        try {
+            NetworkStats stats =
+                    new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+            Bucket bucket = stats.getDeviceSummaryForNetwork();
+            stats.close();
+            return bucket;
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+        return null; // To make the compiler happy.
+    }
+
+    /**
+     * Query network usage statistics summaries. Result is summarised data usage for the whole
+     * device. Result is a single Bucket aggregated over time, state, uid, tag, metered, and
+     * roaming. This means the bucket's start and end timestamp are going to be the same as the
+     * 'startTime' and 'endTime' parameters. State is going to be
+     * {@link NetworkStats.Bucket#STATE_ALL}, uid {@link NetworkStats.Bucket#UID_ALL},
+     * tag {@link NetworkStats.Bucket#TAG_NONE},
+     * default network {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered {@link NetworkStats.Bucket#METERED_ALL},
+     * and roaming {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Bucket object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public Bucket querySummaryForDevice(int networkType, String subscriberId,
+            long startTime, long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        return querySummaryForDevice(template, startTime, endTime);
+    }
+
+    /**
+     * Query network usage statistics summaries. Result is summarised data usage for all uids
+     * belonging to calling user. Result is a single Bucket aggregated over time, state and uid.
+     * This means the bucket's start and end timestamp are going to be the same as the 'startTime'
+     * and 'endTime' parameters. State is going to be {@link NetworkStats.Bucket#STATE_ALL},
+     * uid {@link NetworkStats.Bucket#UID_ALL}, tag {@link NetworkStats.Bucket#TAG_NONE},
+     * metered {@link NetworkStats.Bucket#METERED_ALL}, and roaming
+     * {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Bucket object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public Bucket querySummaryForUser(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        NetworkStats stats;
+        stats = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+        stats.startSummaryEnumeration();
+
+        stats.close();
+        return stats.getSummaryAggregate();
+    }
+
+    /**
+     * Query network usage statistics summaries. Result filtered to include only uids belonging to
+     * calling user. Result is aggregated over time, hence all buckets will have the same start and
+     * end timestamps. Not aggregated over state, uid, default network, metered, or roaming. This
+     * means buckets' start and end timestamps are going to be the same as the 'startTime' and
+     * 'endTime' parameters. State, uid, metered, and roaming are going to vary, and tag is going to
+     * be the same.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public NetworkStats querySummary(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        return querySummary(template, startTime, endTime);
+    }
+
+    /**
+     * Query network usage statistics summaries.
+     *
+     * The results will only include traffic made by UIDs belonging to the calling user profile.
+     * The results are aggregated over time, so that all buckets will have the same start and
+     * end timestamps as the passed arguments. Not aggregated over state, uid, default network,
+     * metered, or roaming.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param startTime Start of period, in milliseconds since the Unix epoch, see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period, in milliseconds since the Unix epoch, see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics which is described above.
+     * @hide
+     */
+    @NonNull
+    @SystemApi(client = MODULE_LIBRARIES)
+    @WorkerThread
+    public NetworkStats querySummary(@NonNull NetworkTemplate template, long startTime,
+            long endTime) throws SecurityException {
+        Objects.requireNonNull(template);
+        try {
+            NetworkStats result =
+                    new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+            result.startSummaryEnumeration();
+            return result;
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+        return null; // To make the compiler happy.
+    }
+
+    /**
+     * Query tagged network usage statistics summaries.
+     *
+     * The results will only include tagged traffic made by UIDs belonging to the calling user
+     * profile. The results are aggregated over time, so that all buckets will have the same
+     * start and end timestamps as the passed arguments. Not aggregated over state, uid,
+     * default network, metered, or roaming.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param startTime Start of period, in milliseconds since the Unix epoch, see
+     *            {@link System#currentTimeMillis}.
+     * @param endTime End of period, in milliseconds since the Unix epoch, see
+     *            {@link System#currentTimeMillis}.
+     * @return Statistics which is described above.
+     * @hide
+     */
+    @NonNull
+    @SystemApi(client = MODULE_LIBRARIES)
+    @WorkerThread
+    public NetworkStats queryTaggedSummary(@NonNull NetworkTemplate template, long startTime,
+            long endTime) throws SecurityException {
+        Objects.requireNonNull(template);
+        try {
+            NetworkStats result =
+                    new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+            result.startTaggedSummaryEnumeration();
+            return result;
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+        return null; // To make the compiler happy.
+    }
+
+    /**
+     * Query usage statistics details for networks matching a given {@link NetworkTemplate}.
+     *
+     * Result is not aggregated over time. This means buckets' start and
+     * end timestamps will be between 'startTime' and 'endTime' parameters.
+     * <p>Only includes buckets whose entire time period is included between
+     * startTime and endTime. Doesn't interpolate or return partial buckets.
+     * Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param startTime Start of period, in milliseconds since the Unix epoch, see
+     *                  {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period, in milliseconds since the Unix epoch, see
+     *                {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics which is described above.
+     * @hide
+     */
+    @NonNull
+    @SystemApi(client = MODULE_LIBRARIES)
+    @WorkerThread
+    public NetworkStats queryDetailsForDevice(@NonNull NetworkTemplate template,
+            long startTime, long endTime) {
+        Objects.requireNonNull(template);
+        try {
+            final NetworkStats result =
+                    new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+            result.startHistoryDeviceEnumeration();
+            return result;
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+
+        return null; // To make the compiler happy.
+    }
+
+    /**
+     * Query network usage statistics details for a given uid.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @see #queryDetailsForUidTagState(int, String, long, long, int, int, int)
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUid(int networkType, String subscriberId,
+            long startTime, long endTime, int uid) throws SecurityException {
+        return queryDetailsForUidTagState(networkType, subscriberId, startTime, endTime, uid,
+            NetworkStats.Bucket.TAG_NONE, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /** @hide */
+    public NetworkStats queryDetailsForUid(NetworkTemplate template,
+            long startTime, long endTime, int uid) throws SecurityException {
+        return queryDetailsForUidTagState(template, startTime, endTime, uid,
+                NetworkStats.Bucket.TAG_NONE, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /**
+     * Query network usage statistics details for a given uid and tag.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @see #queryDetailsForUidTagState(int, String, long, long, int, int, int)
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUidTag(int networkType, String subscriberId,
+            long startTime, long endTime, int uid, int tag) throws SecurityException {
+        return queryDetailsForUidTagState(networkType, subscriberId, startTime, endTime, uid,
+            tag, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /**
+     * Query network usage statistics details for a given uid, tag, and state. Only usable for uids
+     * belonging to calling user. Result is not aggregated over time. This means buckets' start and
+     * end timestamps are going to be between 'startTime' and 'endTime' parameters. The uid is going
+     * to be the same as the 'uid' parameter, the tag the same as the 'tag' parameter, and the state
+     * the same as the 'state' parameter.
+     * defaultNetwork is going to be {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered is going to be {@link NetworkStats.Bucket#METERED_ALL}, and
+     * roaming is going to be {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * <p>Only includes buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets. Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param uid UID of app
+     * @param tag TAG of interest. Use {@link NetworkStats.Bucket#TAG_NONE} for aggregated data
+     *            across all the tags.
+     * @param state state of interest. Use {@link NetworkStats.Bucket#STATE_ALL} to aggregate
+     *            traffic from all states.
+     * @return Statistics object or null if an error happened during statistics collection.
+     * @throws SecurityException if permissions are insufficient to read network statistics.
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUidTagState(int networkType, String subscriberId,
+            long startTime, long endTime, int uid, int tag, int state) throws SecurityException {
+        NetworkTemplate template;
+        template = createTemplate(networkType, subscriberId);
+
+        return queryDetailsForUidTagState(template, startTime, endTime, uid, tag, state);
+    }
+
+    /**
+     * Query network usage statistics details for a given template, uid, tag, and state.
+     *
+     * Only usable for uids belonging to calling user. Result is not aggregated over time.
+     * This means buckets' start and end timestamps are going to be between 'startTime' and
+     * 'endTime' parameters. The uid is going to be the same as the 'uid' parameter, the tag
+     * the same as the 'tag' parameter, and the state the same as the 'state' parameter.
+     * defaultNetwork is going to be {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered is going to be {@link NetworkStats.Bucket#METERED_ALL}, and
+     * roaming is going to be {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * <p>Only includes buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets. Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param startTime Start of period, in milliseconds since the Unix epoch, see
+     *                  {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period, in milliseconds since the Unix epoch, see
+     *                {@link java.lang.System#currentTimeMillis}.
+     * @param uid UID of app
+     * @param tag TAG of interest. Use {@link NetworkStats.Bucket#TAG_NONE} for aggregated data
+     *            across all the tags.
+     * @param state state of interest. Use {@link NetworkStats.Bucket#STATE_ALL} to aggregate
+     *            traffic from all states.
+     * @return Statistics which is described above.
+     * @hide
+     */
+    @NonNull
+    @SystemApi(client = MODULE_LIBRARIES)
+    @WorkerThread
+    public NetworkStats queryDetailsForUidTagState(@NonNull NetworkTemplate template,
+            long startTime, long endTime, int uid, int tag, int state) throws SecurityException {
+        Objects.requireNonNull(template);
+        try {
+            final NetworkStats result = new NetworkStats(
+                    mContext, template, mFlags, startTime, endTime, mService);
+            result.startHistoryUidEnumeration(uid, tag, state);
+            return result;
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error while querying stats for uid=" + uid + " tag=" + tag
+                    + " state=" + state, e);
+            e.rethrowFromSystemServer();
+        }
+
+        return null; // To make the compiler happy.
+    }
+
+    /**
+     * Query network usage statistics details. Result filtered to include only uids belonging to
+     * calling user. Result is aggregated over state but not aggregated over time, uid, tag,
+     * metered, nor roaming. This means buckets' start and end timestamps are going to be between
+     * 'startTime' and 'endTime' parameters. State is going to be
+     * {@link NetworkStats.Bucket#STATE_ALL}, uid will vary,
+     * tag {@link NetworkStats.Bucket#TAG_NONE},
+     * default network is going to be {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered is going to be {@link NetworkStats.Bucket#METERED_ALL},
+     * and roaming is going to be {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * <p>Only includes buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets. Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public NetworkStats queryDetails(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        NetworkStats result;
+        result = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+        result.startUserUidEnumeration();
+        return result;
+    }
+
+    /**
+     * Query realtime mobile network usage statistics.
+     *
+     * Return a snapshot of current UID network statistics, as it applies
+     * to the mobile radios of the device. The snapshot will include any
+     * tethering traffic, video calling data usage and count of
+     * network operations set by {@link TrafficStats#incrementOperationCount}
+     * made over a mobile radio.
+     * The snapshot will not include any statistics that cannot be seen by
+     * the kernel, e.g. statistics reported by {@link NetworkStatsProvider}s.
+     *
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    @NonNull public android.net.NetworkStats getMobileUidStats() {
+        try {
+            return mService.getUidStatsForTransport(TRANSPORT_CELLULAR);
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when get Mobile uid stats");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Query realtime Wi-Fi network usage statistics.
+     *
+     * Return a snapshot of current UID network statistics, as it applies
+     * to the Wi-Fi radios of the device. The snapshot will include any
+     * tethering traffic, video calling data usage and count of
+     * network operations set by {@link TrafficStats#incrementOperationCount}
+     * made over a Wi-Fi radio.
+     * The snapshot will not include any statistics that cannot be seen by
+     * the kernel, e.g. statistics reported by {@link NetworkStatsProvider}s.
+     *
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    @NonNull public android.net.NetworkStats getWifiUidStats() {
+        try {
+            return mService.getUidStatsForTransport(TRANSPORT_WIFI);
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when get WiFi uid stats");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Registers to receive notifications about data usage on specified networks.
+     *
+     * <p>The callbacks will continue to be called as long as the process is alive or
+     * {@link #unregisterUsageCallback} is called.
+     *
+     * @param template Template used to match networks. See {@link NetworkTemplate}.
+     * @param thresholdBytes Threshold in bytes to be notified on. Provided values lower than 2MiB
+     *                       will be clamped for callers except callers with the NETWORK_STACK
+     *                       permission.
+     * @param executor The executor on which callback will be invoked. The provided {@link Executor}
+     *                 must run callback sequentially, otherwise the order of callbacks cannot be
+     *                 guaranteed.
+     * @param callback The {@link UsageCallback} that the system will call when data usage
+     *                 has exceeded the specified threshold.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK}, conditional = true)
+    public void registerUsageCallback(@NonNull NetworkTemplate template, long thresholdBytes,
+            @NonNull @CallbackExecutor Executor executor, @NonNull UsageCallback callback) {
+        Objects.requireNonNull(template, "NetworkTemplate cannot be null");
+        Objects.requireNonNull(callback, "UsageCallback cannot be null");
+        Objects.requireNonNull(executor, "Executor cannot be null");
+
+        final DataUsageRequest request = new DataUsageRequest(DataUsageRequest.REQUEST_ID_UNSET,
+                template, thresholdBytes);
+        try {
+            final UsageCallbackWrapper callbackWrapper =
+                    new UsageCallbackWrapper(executor, callback);
+            callback.request = mService.registerUsageCallback(
+                    mContext.getOpPackageName(), request, callbackWrapper);
+            if (DBG) Log.d(TAG, "registerUsageCallback returned " + callback.request);
+
+            if (callback.request == null) {
+                Log.e(TAG, "Request from callback is null; should not happen");
+            }
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when registering callback");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Registers to receive notifications about data usage on specified networks.
+     *
+     * @see #registerUsageCallback(int, String, long, UsageCallback, Handler)
+     */
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback) {
+        registerUsageCallback(networkType, subscriberId, thresholdBytes, callback,
+                null /* handler */);
+    }
+
+    /**
+     * Registers to receive notifications about data usage on specified networks.
+     *
+     * <p>The callbacks will continue to be called as long as the process is live or
+     * {@link #unregisterUsageCallback} is called.
+     *
+     * @param networkType Type of network to monitor. Either
+                  {@link ConnectivityManager#TYPE_MOBILE} or {@link ConnectivityManager#TYPE_WIFI}.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when registering for the mobile network type to receive
+     *                     notifications for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param thresholdBytes Threshold in bytes to be notified on.
+     * @param callback The {@link UsageCallback} that the system will call when data usage
+     *            has exceeded the specified threshold.
+     * @param handler to dispatch callback events through, otherwise if {@code null} it uses
+     *            the calling thread.
+     */
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback, @Nullable Handler handler) {
+        NetworkTemplate template = createTemplate(networkType, subscriberId);
+        if (DBG) {
+            Log.d(TAG, "registerUsageCallback called with: {"
+                    + " networkType=" + networkType
+                    + " subscriberId=" + subscriberId
+                    + " thresholdBytes=" + thresholdBytes
+                    + " }");
+        }
+
+        final Executor executor = handler == null ? r -> r.run() : r -> handler.post(r);
+
+        registerUsageCallback(template, thresholdBytes, executor, callback);
+    }
+
+    /**
+     * Unregisters callbacks on data usage.
+     *
+     * @param callback The {@link UsageCallback} used when registering.
+     */
+    public void unregisterUsageCallback(UsageCallback callback) {
+        if (callback == null || callback.request == null
+                || callback.request.requestId == DataUsageRequest.REQUEST_ID_UNSET) {
+            throw new IllegalArgumentException("Invalid UsageCallback");
+        }
+        try {
+            mService.unregisterUsageRequest(callback.request);
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when unregistering callback");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Base class for usage callbacks. Should be extended by applications wanting notifications.
+     */
+    public static abstract class UsageCallback {
+        /**
+         * Called when data usage has reached the given threshold.
+         *
+         * Called by {@code NetworkStatsService} when the registered threshold is reached.
+         * If a caller implements {@link #onThresholdReached(NetworkTemplate)}, the system
+         * will not call {@link #onThresholdReached(int, String)}.
+         *
+         * @param template The {@link NetworkTemplate} that associated with this callback.
+         * @hide
+         */
+        @SystemApi(client = MODULE_LIBRARIES)
+        public void onThresholdReached(@NonNull NetworkTemplate template) {
+            // Backward compatibility for those who didn't override this function.
+            final int networkType = networkTypeForTemplate(template);
+            if (networkType != ConnectivityManager.TYPE_NONE) {
+                final String subscriberId = template.getSubscriberIds().isEmpty() ? null
+                        : template.getSubscriberIds().iterator().next();
+                onThresholdReached(networkType, subscriberId);
+            }
+        }
+
+        /**
+         * Called when data usage has reached the given threshold.
+         */
+        public abstract void onThresholdReached(int networkType, String subscriberId);
+
+        /**
+         * @hide used for internal bookkeeping
+         */
+        private DataUsageRequest request;
+
+        /**
+         * Get network type from a template if feasible.
+         *
+         * @param template the target {@link NetworkTemplate}.
+         * @return legacy network type, only supports for the types which is already supported in
+         *         {@link #registerUsageCallback(int, String, long, UsageCallback, Handler)}.
+         *         {@link ConnectivityManager#TYPE_NONE} for other types.
+         */
+        private static int networkTypeForTemplate(@NonNull NetworkTemplate template) {
+            switch (template.getMatchRule()) {
+                case NetworkTemplate.MATCH_MOBILE:
+                    return ConnectivityManager.TYPE_MOBILE;
+                case NetworkTemplate.MATCH_WIFI:
+                    return ConnectivityManager.TYPE_WIFI;
+                default:
+                    return ConnectivityManager.TYPE_NONE;
+            }
+        }
+    }
+
+    /**
+     * Registers a custom provider of {@link android.net.NetworkStats} to provide network statistics
+     * to the system. To unregister, invoke {@link #unregisterNetworkStatsProvider}.
+     * Note that no de-duplication of statistics between providers is performed, so each provider
+     * must only report network traffic that is not being reported by any other provider. Also note
+     * that the provider cannot be re-registered after unregistering.
+     *
+     * @param tag a human readable identifier of the custom network stats provider. This is only
+     *            used for debugging.
+     * @param provider the subclass of {@link NetworkStatsProvider} that needs to be
+     *                 registered to the system.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_STATS_PROVIDER,
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK})
+    @NonNull public void registerNetworkStatsProvider(
+            @NonNull String tag,
+            @NonNull NetworkStatsProvider provider) {
+        try {
+            if (provider.getProviderCallbackBinder() != null) {
+                throw new IllegalArgumentException("provider is already registered");
+            }
+            final INetworkStatsProviderCallback cbBinder =
+                    mService.registerNetworkStatsProvider(tag, provider.getProviderBinder());
+            provider.setProviderCallbackBinder(cbBinder);
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Unregisters an instance of {@link NetworkStatsProvider}.
+     *
+     * @param provider the subclass of {@link NetworkStatsProvider} that needs to be
+     *                 unregistered to the system.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_STATS_PROVIDER,
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK})
+    @NonNull public void unregisterNetworkStatsProvider(@NonNull NetworkStatsProvider provider) {
+        try {
+            provider.getProviderCallbackBinderOrThrow().unregister();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    private static NetworkTemplate createTemplate(int networkType, String subscriberId) {
+        final NetworkTemplate template;
+        switch (networkType) {
+            case ConnectivityManager.TYPE_MOBILE:
+                template = subscriberId == null
+                        ? NetworkTemplate.buildTemplateMobileWildcard()
+                        : NetworkTemplate.buildTemplateMobileAll(subscriberId);
+                break;
+            case ConnectivityManager.TYPE_WIFI:
+                template = TextUtils.isEmpty(subscriberId)
+                        ? NetworkTemplate.buildTemplateWifiWildcard()
+                        : NetworkTemplate.buildTemplateWifi(NetworkTemplate.WIFI_NETWORKID_ALL,
+                                subscriberId);
+                break;
+            default:
+                throw new IllegalArgumentException("Cannot create template for network type "
+                        + networkType + ", subscriberId '"
+                        + NetworkIdentityUtils.scrubSubscriberId(subscriberId) + "'.");
+        }
+        return template;
+    }
+
+    /**
+     * Notify {@code NetworkStatsService} about network status changed.
+     *
+     * Notifies NetworkStatsService of network state changes for data usage accounting purposes.
+     *
+     * To avoid races that attribute data usage to wrong network, such as new network with
+     * the same interface after SIM hot-swap, this function will not return until
+     * {@code NetworkStatsService} finishes its work of retrieving traffic statistics from
+     * all data sources.
+     *
+     * @param defaultNetworks the list of all networks that could be used by network traffic that
+     *                        does not explicitly select a network.
+     * @param networkStateSnapshots a list of {@link NetworkStateSnapshot}s, one for
+     *                              each network that is currently connected.
+     * @param activeIface the active (i.e., connected) default network interface for the calling
+     *                    uid. Used to determine on which network future calls to
+     *                    {@link android.net.TrafficStats#incrementOperationCount} applies to.
+     * @param underlyingNetworkInfos the list of underlying network information for all
+     *                               currently-connected VPNs.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void notifyNetworkStatus(
+            @NonNull List<Network> defaultNetworks,
+            @NonNull List<NetworkStateSnapshot> networkStateSnapshots,
+            @Nullable String activeIface,
+            @NonNull List<UnderlyingNetworkInfo> underlyingNetworkInfos) {
+        try {
+            Objects.requireNonNull(defaultNetworks);
+            Objects.requireNonNull(networkStateSnapshots);
+            Objects.requireNonNull(underlyingNetworkInfos);
+            mService.notifyNetworkStatus(defaultNetworks.toArray(new Network[0]),
+                    networkStateSnapshots.toArray(new NetworkStateSnapshot[0]), activeIface,
+                    underlyingNetworkInfos.toArray(new UnderlyingNetworkInfo[0]));
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    private static class UsageCallbackWrapper extends IUsageCallback.Stub {
+        // Null if unregistered.
+        private volatile UsageCallback mCallback;
+
+        private final Executor mExecutor;
+
+        UsageCallbackWrapper(@NonNull Executor executor, @NonNull UsageCallback callback) {
+            mCallback = callback;
+            mExecutor = executor;
+        }
+
+        @Override
+        public void onThresholdReached(DataUsageRequest request) {
+            // Copy it to a local variable in case mCallback changed inside the if condition.
+            final UsageCallback callback = mCallback;
+            if (callback != null) {
+                mExecutor.execute(() -> callback.onThresholdReached(request.template));
+            } else {
+                Log.e(TAG, "onThresholdReached with released callback for " + request);
+            }
+        }
+
+        @Override
+        public void onCallbackReleased(DataUsageRequest request) {
+            if (DBG) Log.d(TAG, "callback released for " + request);
+            mCallback = null;
+        }
+    }
+
+    /**
+     * Mark given UID as being in foreground for stats purposes.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void noteUidForeground(int uid, boolean uidForeground) {
+        try {
+            mService.noteUidForeground(uid, uidForeground);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Set default value of global alert bytes, the value will be clamped to [128kB, 2MB].
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            Manifest.permission.NETWORK_STACK})
+    public void setDefaultGlobalAlert(long alertBytes) {
+        try {
+            // TODO: Sync internal naming with the API surface.
+            mService.advisePersistThreshold(alertBytes);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Force update of statistics.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void forceUpdate() {
+        try {
+            mService.forceUpdate();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Set the warning and limit to all registered custom network stats providers.
+     * Note that invocation of any interface will be sent to all providers.
+     *
+     * Asynchronicity notes : because traffic may be happening on the device at the same time, it
+     * doesn't make sense to wait for the warning and limit to be set – a caller still wouldn't
+     * know when exactly it was effective. All that can matter is that it's done quickly. Also,
+     * this method can't fail, so there is no status to return. All providers will see the new
+     * values soon.
+     * As such, this method returns immediately and sends the warning and limit to all providers
+     * as soon as possible through a one-way binder call.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void setStatsProviderWarningAndLimitAsync(@NonNull String iface, long warning,
+            long limit) {
+        try {
+            mService.setStatsProviderWarningAndLimitAsync(iface, warning, limit);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Get a RAT type representative of a group of RAT types for network statistics.
+     *
+     * Collapse the given Radio Access Technology (RAT) type into a bucket that
+     * is representative of the original RAT type for network statistics. The
+     * mapping mostly corresponds to {@code TelephonyManager#NETWORK_CLASS_BIT_MASK_*}
+     * but with adaptations specific to the virtual types introduced by
+     * networks stats.
+     *
+     * @param ratType An integer defined in {@code TelephonyManager#NETWORK_TYPE_*}.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static int getCollapsedRatType(int ratType) {
+        switch (ratType) {
+            case TelephonyManager.NETWORK_TYPE_GPRS:
+            case TelephonyManager.NETWORK_TYPE_GSM:
+            case TelephonyManager.NETWORK_TYPE_EDGE:
+            case TelephonyManager.NETWORK_TYPE_IDEN:
+            case TelephonyManager.NETWORK_TYPE_CDMA:
+            case TelephonyManager.NETWORK_TYPE_1xRTT:
+                return TelephonyManager.NETWORK_TYPE_GSM;
+            case TelephonyManager.NETWORK_TYPE_EVDO_0:
+            case TelephonyManager.NETWORK_TYPE_EVDO_A:
+            case TelephonyManager.NETWORK_TYPE_EVDO_B:
+            case TelephonyManager.NETWORK_TYPE_EHRPD:
+            case TelephonyManager.NETWORK_TYPE_UMTS:
+            case TelephonyManager.NETWORK_TYPE_HSDPA:
+            case TelephonyManager.NETWORK_TYPE_HSUPA:
+            case TelephonyManager.NETWORK_TYPE_HSPA:
+            case TelephonyManager.NETWORK_TYPE_HSPAP:
+            case TelephonyManager.NETWORK_TYPE_TD_SCDMA:
+                return TelephonyManager.NETWORK_TYPE_UMTS;
+            case TelephonyManager.NETWORK_TYPE_LTE:
+            case TelephonyManager.NETWORK_TYPE_IWLAN:
+                return TelephonyManager.NETWORK_TYPE_LTE;
+            case TelephonyManager.NETWORK_TYPE_NR:
+                return TelephonyManager.NETWORK_TYPE_NR;
+            // Virtual RAT type for 5G NSA mode, see
+            // {@link NetworkStatsManager#NETWORK_TYPE_5G_NSA}.
+            case NetworkStatsManager.NETWORK_TYPE_5G_NSA:
+                return NetworkStatsManager.NETWORK_TYPE_5G_NSA;
+            default:
+                return TelephonyManager.NETWORK_TYPE_UNKNOWN;
+        }
+    }
+}
diff --git a/framework-t/src/android/net/ConnectivityFrameworkInitializerTiramisu.java b/framework-t/src/android/net/ConnectivityFrameworkInitializerTiramisu.java
new file mode 100644
index 0000000..61b34d0
--- /dev/null
+++ b/framework-t/src/android/net/ConnectivityFrameworkInitializerTiramisu.java
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.SystemApi;
+import android.app.SystemServiceRegistry;
+import android.app.usage.NetworkStatsManager;
+import android.content.Context;
+import android.net.nsd.INsdManager;
+import android.net.nsd.NsdManager;
+
+/**
+ * Class for performing registration for Connectivity services which are exposed via updatable APIs
+ * since Android T.
+ *
+ * @hide
+ */
+@SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+public final class ConnectivityFrameworkInitializerTiramisu {
+    private ConnectivityFrameworkInitializerTiramisu() {}
+
+    /**
+     * Called by {@link SystemServiceRegistry}'s static initializer and registers NetworkStats, nsd,
+     * ipsec and ethernet services to {@link Context}, so that {@link Context#getSystemService} can
+     * return them.
+     *
+     * @throws IllegalStateException if this is called anywhere besides
+     * {@link SystemServiceRegistry}.
+     */
+    public static void registerServiceWrappers() {
+        SystemServiceRegistry.registerContextAwareService(
+                Context.NSD_SERVICE,
+                NsdManager.class,
+                (context, serviceBinder) -> {
+                    INsdManager service = INsdManager.Stub.asInterface(serviceBinder);
+                    return new NsdManager(context, service);
+                }
+        );
+
+        SystemServiceRegistry.registerContextAwareService(
+                Context.IPSEC_SERVICE,
+                IpSecManager.class,
+                (context, serviceBinder) -> {
+                    IIpSecService service = IIpSecService.Stub.asInterface(serviceBinder);
+                    return new IpSecManager(context, service);
+                }
+        );
+
+        SystemServiceRegistry.registerContextAwareService(
+                Context.NETWORK_STATS_SERVICE,
+                NetworkStatsManager.class,
+                (context, serviceBinder) -> {
+                    INetworkStatsService service =
+                            INetworkStatsService.Stub.asInterface(serviceBinder);
+                    return new NetworkStatsManager(context, service);
+                }
+        );
+
+        SystemServiceRegistry.registerContextAwareService(
+                Context.ETHERNET_SERVICE,
+                EthernetManager.class,
+                (context, serviceBinder) -> {
+                    IEthernetManager service = IEthernetManager.Stub.asInterface(serviceBinder);
+                    return new EthernetManager(context, service);
+                }
+        );
+    }
+}
diff --git a/framework-t/src/android/net/DataUsageRequest.aidl b/framework-t/src/android/net/DataUsageRequest.aidl
new file mode 100644
index 0000000..d1937c7
--- /dev/null
+++ b/framework-t/src/android/net/DataUsageRequest.aidl
@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2016, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable DataUsageRequest;
diff --git a/framework-t/src/android/net/DataUsageRequest.java b/framework-t/src/android/net/DataUsageRequest.java
new file mode 100644
index 0000000..b06d515
--- /dev/null
+++ b/framework-t/src/android/net/DataUsageRequest.java
@@ -0,0 +1,112 @@
+/**
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.net;
+
+import android.annotation.Nullable;
+import android.net.NetworkTemplate;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.Objects;
+
+/**
+ * Defines a request to register a callbacks. Used to be notified on data usage via
+ * {@link android.app.usage.NetworkStatsManager#registerDataUsageCallback}.
+ * If no {@code uid}s are set, callbacks are restricted to device-owners,
+ * carrier-privileged apps, or system apps.
+ *
+ * @hide
+ */
+public final class DataUsageRequest implements Parcelable {
+
+    public static final String PARCELABLE_KEY = "DataUsageRequest";
+    public static final int REQUEST_ID_UNSET = 0;
+
+    /**
+     * Identifies the request.  {@link DataUsageRequest}s should only be constructed by
+     * the Framework and it is used internally to identify the request.
+     */
+    public final int requestId;
+
+    /**
+     * {@link NetworkTemplate} describing the network to monitor.
+     */
+    public final NetworkTemplate template;
+
+    /**
+     * Threshold in bytes to be notified on.
+     */
+    public final long thresholdInBytes;
+
+    public DataUsageRequest(int requestId, NetworkTemplate template, long thresholdInBytes) {
+        this.requestId = requestId;
+        this.template = template;
+        this.thresholdInBytes = thresholdInBytes;
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeInt(requestId);
+        dest.writeParcelable(template, flags);
+        dest.writeLong(thresholdInBytes);
+    }
+
+    public static final @android.annotation.NonNull Creator<DataUsageRequest> CREATOR =
+            new Creator<DataUsageRequest>() {
+                @Override
+                public DataUsageRequest createFromParcel(Parcel in) {
+                    int requestId = in.readInt();
+                    NetworkTemplate template = in.readParcelable(null);
+                    long thresholdInBytes = in.readLong();
+                    DataUsageRequest result = new DataUsageRequest(requestId, template,
+                            thresholdInBytes);
+                    return result;
+                }
+
+                @Override
+                public DataUsageRequest[] newArray(int size) {
+                    return new DataUsageRequest[size];
+                }
+            };
+
+    @Override
+    public String toString() {
+        return "DataUsageRequest [ requestId=" + requestId
+                + ", networkTemplate=" + template
+                + ", thresholdInBytes=" + thresholdInBytes + " ]";
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof DataUsageRequest == false) return false;
+        DataUsageRequest that = (DataUsageRequest) obj;
+        return that.requestId == this.requestId
+                && Objects.equals(that.template, this.template)
+                && that.thresholdInBytes == this.thresholdInBytes;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(requestId, template, thresholdInBytes);
+   }
+
+}
diff --git a/framework-t/src/android/net/EthernetManager.java b/framework-t/src/android/net/EthernetManager.java
new file mode 100644
index 0000000..e02ea89
--- /dev/null
+++ b/framework-t/src/android/net/EthernetManager.java
@@ -0,0 +1,729 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.CallbackExecutor;
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresFeature;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
+import android.annotation.SystemService;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Build;
+import android.os.OutcomeReceiver;
+import android.os.RemoteException;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.modules.utils.BackgroundThread;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.Executor;
+import java.util.function.IntConsumer;
+
+/**
+ * A class that manages and configures Ethernet interfaces.
+ *
+ * @hide
+ */
+@SystemApi
+@SystemService(Context.ETHERNET_SERVICE)
+public class EthernetManager {
+    private static final String TAG = "EthernetManager";
+
+    private final IEthernetManager mService;
+    @GuardedBy("mListenerLock")
+    private final ArrayList<ListenerInfo<InterfaceStateListener>> mIfaceListeners =
+            new ArrayList<>();
+    @GuardedBy("mListenerLock")
+    private final ArrayList<ListenerInfo<IntConsumer>> mEthernetStateListeners =
+            new ArrayList<>();
+    final Object mListenerLock = new Object();
+    private final IEthernetServiceListener.Stub mServiceListener =
+            new IEthernetServiceListener.Stub() {
+                @Override
+                public void onEthernetStateChanged(int state) {
+                    synchronized (mListenerLock) {
+                        for (ListenerInfo<IntConsumer> li : mEthernetStateListeners) {
+                            li.executor.execute(() -> {
+                                li.listener.accept(state);
+                            });
+                        }
+                    }
+                }
+
+                @Override
+                public void onInterfaceStateChanged(String iface, int state, int role,
+                        IpConfiguration configuration) {
+                    synchronized (mListenerLock) {
+                        for (ListenerInfo<InterfaceStateListener> li : mIfaceListeners) {
+                            li.executor.execute(() ->
+                                    li.listener.onInterfaceStateChanged(iface, state, role,
+                                            configuration));
+                        }
+                    }
+                }
+            };
+
+    /**
+     * Indicates that Ethernet is disabled.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int ETHERNET_STATE_DISABLED = 0;
+
+    /**
+     * Indicates that Ethernet is enabled.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int ETHERNET_STATE_ENABLED  = 1;
+
+    private static class ListenerInfo<T> {
+        @NonNull
+        public final Executor executor;
+        @NonNull
+        public final T listener;
+
+        private ListenerInfo(@NonNull Executor executor, @NonNull T listener) {
+            this.executor = executor;
+            this.listener = listener;
+        }
+    }
+
+    /**
+     * The interface is absent.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int STATE_ABSENT = 0;
+
+    /**
+     * The interface is present but link is down.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int STATE_LINK_DOWN = 1;
+
+    /**
+     * The interface is present and link is up.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int STATE_LINK_UP = 2;
+
+    /** @hide */
+    @IntDef(prefix = "STATE_", value = {STATE_ABSENT, STATE_LINK_DOWN, STATE_LINK_UP})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface InterfaceState {}
+
+    /**
+     * The interface currently does not have any specific role.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int ROLE_NONE = 0;
+
+    /**
+     * The interface is in client mode (e.g., connected to the Internet).
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int ROLE_CLIENT = 1;
+
+    /**
+     * Ethernet interface is in server mode (e.g., providing Internet access to tethered devices).
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int ROLE_SERVER = 2;
+
+    /** @hide */
+    @IntDef(prefix = "ROLE_", value = {ROLE_NONE, ROLE_CLIENT, ROLE_SERVER})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface Role {}
+
+    /**
+     * A listener that receives notifications about the state of Ethernet interfaces on the system.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public interface InterfaceStateListener {
+        /**
+         * Called when an Ethernet interface changes state.
+         *
+         * @param iface the name of the interface.
+         * @param state the current state of the interface, or {@link #STATE_ABSENT} if the
+         *              interface was removed.
+         * @param role whether the interface is in client mode or server mode.
+         * @param configuration the current IP configuration of the interface.
+         * @hide
+         */
+        @SystemApi(client = MODULE_LIBRARIES)
+        void onInterfaceStateChanged(@NonNull String iface, @InterfaceState int state,
+                @Role int role, @Nullable IpConfiguration configuration);
+    }
+
+    /**
+     * A listener interface to receive notification on changes in Ethernet.
+     * This has never been a supported API. Use {@link InterfaceStateListener} instead.
+     * @hide
+     */
+    public interface Listener extends InterfaceStateListener {
+        /**
+         * Called when Ethernet port's availability is changed.
+         * @param iface Ethernet interface name
+         * @param isAvailable {@code true} if Ethernet port exists.
+         * @hide
+         */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        void onAvailabilityChanged(String iface, boolean isAvailable);
+
+        /** Default implementation for backwards compatibility. Only calls the legacy listener. */
+        default void onInterfaceStateChanged(@NonNull String iface, @InterfaceState int state,
+                @Role int role, @Nullable IpConfiguration configuration) {
+            onAvailabilityChanged(iface, (state >= STATE_LINK_UP));
+        }
+
+    }
+
+    /**
+     * Create a new EthernetManager instance.
+     * Applications will almost always want to use
+     * {@link android.content.Context#getSystemService Context.getSystemService()} to retrieve
+     * the standard {@link android.content.Context#ETHERNET_SERVICE Context.ETHERNET_SERVICE}.
+     * @hide
+     */
+    public EthernetManager(Context context, IEthernetManager service) {
+        mService = service;
+    }
+
+    /**
+     * Get Ethernet configuration.
+     * @return the Ethernet Configuration, contained in {@link IpConfiguration}.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public IpConfiguration getConfiguration(String iface) {
+        try {
+            return mService.getConfiguration(iface);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Set Ethernet configuration.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public void setConfiguration(@NonNull String iface, @NonNull IpConfiguration config) {
+        try {
+            mService.setConfiguration(iface, config);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Indicates whether the system currently has one or more Ethernet interfaces.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public boolean isAvailable() {
+        return getAvailableInterfaces().length > 0;
+    }
+
+    /**
+     * Indicates whether the system has given interface.
+     *
+     * @param iface Ethernet interface name
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public boolean isAvailable(String iface) {
+        try {
+            return mService.isAvailable(iface);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Adds a listener.
+     * This has never been a supported API. Use {@link #addInterfaceStateListener} instead.
+     *
+     * @param listener A {@link Listener} to add.
+     * @throws IllegalArgumentException If the listener is null.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public void addListener(@NonNull Listener listener) {
+        addListener(listener, BackgroundThread.getExecutor());
+    }
+
+    /**
+     * Adds a listener.
+     * This has never been a supported API. Use {@link #addInterfaceStateListener} instead.
+     *
+     * @param listener A {@link Listener} to add.
+     * @param executor Executor to run callbacks on.
+     * @throws IllegalArgumentException If the listener or executor is null.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public void addListener(@NonNull Listener listener, @NonNull Executor executor) {
+        addInterfaceStateListener(executor, listener);
+    }
+
+    /**
+     * Listen to changes in the state of Ethernet interfaces.
+     *
+     * Adds a listener to receive notification for any state change of all existing Ethernet
+     * interfaces.
+     * <p>{@link Listener#onInterfaceStateChanged} will be triggered immediately for all
+     * existing interfaces upon adding a listener. The same method will be called on the
+     * listener every time any of the interface changes state. In particular, if an
+     * interface is removed, it will be called with state {@link #STATE_ABSENT}.
+     * <p>Use {@link #removeInterfaceStateListener} with the same object to stop listening.
+     *
+     * @param executor Executor to run callbacks on.
+     * @param listener A {@link Listener} to add.
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void addInterfaceStateListener(@NonNull Executor executor,
+            @NonNull InterfaceStateListener listener) {
+        if (listener == null || executor == null) {
+            throw new NullPointerException("listener and executor must not be null");
+        }
+        synchronized (mListenerLock) {
+            maybeAddServiceListener();
+            mIfaceListeners.add(new ListenerInfo<InterfaceStateListener>(executor, listener));
+        }
+    }
+
+    @GuardedBy("mListenerLock")
+    private void maybeAddServiceListener() {
+        if (!mIfaceListeners.isEmpty() || !mEthernetStateListeners.isEmpty()) return;
+
+        try {
+            mService.addListener(mServiceListener);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+
+    }
+
+    /**
+     * Returns an array of available Ethernet interface names.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public String[] getAvailableInterfaces() {
+        try {
+            return mService.getAvailableInterfaces();
+        } catch (RemoteException e) {
+            throw e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Removes a listener.
+     *
+     * @param listener A {@link Listener} to remove.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void removeInterfaceStateListener(@NonNull InterfaceStateListener listener) {
+        Objects.requireNonNull(listener);
+        synchronized (mListenerLock) {
+            mIfaceListeners.removeIf(l -> l.listener == listener);
+            maybeRemoveServiceListener();
+        }
+    }
+
+    @GuardedBy("mListenerLock")
+    private void maybeRemoveServiceListener() {
+        if (!mIfaceListeners.isEmpty() || !mEthernetStateListeners.isEmpty()) return;
+
+        try {
+            mService.removeListener(mServiceListener);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Removes a listener.
+     * This has never been a supported API. Use {@link #removeInterfaceStateListener} instead.
+     * @param listener A {@link Listener} to remove.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public void removeListener(@NonNull Listener listener) {
+        if (listener == null) {
+            throw new IllegalArgumentException("listener must not be null");
+        }
+        removeInterfaceStateListener(listener);
+    }
+
+    /**
+     * Whether to treat interfaces created by {@link TestNetworkManager#createTapInterface}
+     * as Ethernet interfaces. The effects of this method apply to any test interfaces that are
+     * already present on the system.
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void setIncludeTestInterfaces(boolean include) {
+        try {
+            mService.setIncludeTestInterfaces(include);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * A request for a tethered interface.
+     */
+    public static class TetheredInterfaceRequest {
+        private final IEthernetManager mService;
+        private final ITetheredInterfaceCallback mCb;
+
+        private TetheredInterfaceRequest(@NonNull IEthernetManager service,
+                @NonNull ITetheredInterfaceCallback cb) {
+            this.mService = service;
+            this.mCb = cb;
+        }
+
+        /**
+         * Release the request, causing the interface to revert back from tethering mode if there
+         * is no other requestor.
+         */
+        public void release() {
+            try {
+                mService.releaseTetheredInterface(mCb);
+            } catch (RemoteException e) {
+                e.rethrowFromSystemServer();
+            }
+        }
+    }
+
+    /**
+     * Callback for {@link #requestTetheredInterface(TetheredInterfaceCallback)}.
+     */
+    public interface TetheredInterfaceCallback {
+        /**
+         * Called when the tethered interface is available.
+         * @param iface The name of the interface.
+         */
+        void onAvailable(@NonNull String iface);
+
+        /**
+         * Called when the tethered interface is now unavailable.
+         */
+        void onUnavailable();
+    }
+
+    /**
+     * Request a tethered interface in tethering mode.
+     *
+     * <p>When this method is called and there is at least one ethernet interface available, the
+     * system will designate one to act as a tethered interface. If there is already a tethered
+     * interface, the existing interface will be used.
+     * @param callback A callback to be called once the request has been fulfilled.
+     */
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_STACK,
+            android.net.NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK
+    })
+    @NonNull
+    public TetheredInterfaceRequest requestTetheredInterface(@NonNull final Executor executor,
+            @NonNull final TetheredInterfaceCallback callback) {
+        Objects.requireNonNull(callback, "Callback must be non-null");
+        Objects.requireNonNull(executor, "Executor must be non-null");
+        final ITetheredInterfaceCallback cbInternal = new ITetheredInterfaceCallback.Stub() {
+            @Override
+            public void onAvailable(String iface) {
+                executor.execute(() -> callback.onAvailable(iface));
+            }
+
+            @Override
+            public void onUnavailable() {
+                executor.execute(() -> callback.onUnavailable());
+            }
+        };
+
+        try {
+            mService.requestTetheredInterface(cbInternal);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+        return new TetheredInterfaceRequest(mService, cbInternal);
+    }
+
+    private static final class NetworkInterfaceOutcomeReceiver
+            extends INetworkInterfaceOutcomeReceiver.Stub {
+        @NonNull
+        private final Executor mExecutor;
+        @NonNull
+        private final OutcomeReceiver<String, EthernetNetworkManagementException> mCallback;
+
+        NetworkInterfaceOutcomeReceiver(
+                @NonNull final Executor executor,
+                @NonNull final OutcomeReceiver<String, EthernetNetworkManagementException>
+                        callback) {
+            Objects.requireNonNull(executor, "Pass a non-null executor");
+            Objects.requireNonNull(callback, "Pass a non-null callback");
+            mExecutor = executor;
+            mCallback = callback;
+        }
+
+        @Override
+        public void onResult(@NonNull String iface) {
+            mExecutor.execute(() -> mCallback.onResult(iface));
+        }
+
+        @Override
+        public void onError(@NonNull EthernetNetworkManagementException e) {
+            mExecutor.execute(() -> mCallback.onError(e));
+        }
+    }
+
+    private NetworkInterfaceOutcomeReceiver makeNetworkInterfaceOutcomeReceiver(
+            @Nullable final Executor executor,
+            @Nullable final OutcomeReceiver<String, EthernetNetworkManagementException> callback) {
+        if (null != callback) {
+            Objects.requireNonNull(executor, "Pass a non-null executor, or a null callback");
+        }
+        final NetworkInterfaceOutcomeReceiver proxy;
+        if (null == callback) {
+            proxy = null;
+        } else {
+            proxy = new NetworkInterfaceOutcomeReceiver(executor, callback);
+        }
+        return proxy;
+    }
+
+    /**
+     * Updates the configuration of an automotive device's ethernet network.
+     *
+     * The {@link EthernetNetworkUpdateRequest} {@code request} argument describes how to update the
+     * configuration for this network.
+     * Use {@link StaticIpConfiguration.Builder} to build a {@code StaticIpConfiguration} object for
+     * this network to put inside the {@code request}.
+     * Similarly, use {@link NetworkCapabilities.Builder} to build a {@code NetworkCapabilities}
+     * object for this network to put inside the {@code request}.
+     *
+     * This function accepts an {@link OutcomeReceiver} that is called once the operation has
+     * finished execution.
+     *
+     * @param iface the name of the interface to act upon.
+     * @param request the {@link EthernetNetworkUpdateRequest} used to set an ethernet network's
+     *                {@link StaticIpConfiguration} and {@link NetworkCapabilities} values.
+     * @param executor an {@link Executor} to execute the callback on. Optional if callback is null.
+     * @param callback an optional {@link OutcomeReceiver} to listen for completion of the
+     *                 operation. On success, {@link OutcomeReceiver#onResult} is called with the
+     *                 interface name. On error, {@link OutcomeReceiver#onError} is called with more
+     *                 information about the error.
+     * @throws SecurityException if the process doesn't hold
+     *                          {@link android.Manifest.permission.MANAGE_ETHERNET_NETWORKS}.
+     * @throws UnsupportedOperationException if called on a non-automotive device or on an
+     *                                       unsupported interface.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK,
+            android.Manifest.permission.MANAGE_ETHERNET_NETWORKS})
+    public void updateConfiguration(
+            @NonNull String iface,
+            @NonNull EthernetNetworkUpdateRequest request,
+            @Nullable @CallbackExecutor Executor executor,
+            @Nullable OutcomeReceiver<String, EthernetNetworkManagementException> callback) {
+        Objects.requireNonNull(iface, "iface must be non-null");
+        Objects.requireNonNull(request, "request must be non-null");
+        final NetworkInterfaceOutcomeReceiver proxy = makeNetworkInterfaceOutcomeReceiver(
+                executor, callback);
+        try {
+            mService.updateConfiguration(iface, request, proxy);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Enable a network interface.
+     *
+     * Enables a previously disabled network interface.
+     * This function accepts an {@link OutcomeReceiver} that is called once the operation has
+     * finished execution.
+     *
+     * @param iface the name of the interface to enable.
+     * @param executor an {@link Executor} to execute the callback on. Optional if callback is null.
+     * @param callback an optional {@link OutcomeReceiver} to listen for completion of the
+     *                 operation. On success, {@link OutcomeReceiver#onResult} is called with the
+     *                 interface name. On error, {@link OutcomeReceiver#onError} is called with more
+     *                 information about the error.
+     * @throws SecurityException if the process doesn't hold
+     *                          {@link android.Manifest.permission.MANAGE_ETHERNET_NETWORKS}.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK,
+            android.Manifest.permission.MANAGE_ETHERNET_NETWORKS})
+    @RequiresFeature(PackageManager.FEATURE_AUTOMOTIVE)
+    public void enableInterface(
+            @NonNull String iface,
+            @Nullable @CallbackExecutor Executor executor,
+            @Nullable OutcomeReceiver<String, EthernetNetworkManagementException> callback) {
+        Objects.requireNonNull(iface, "iface must be non-null");
+        final NetworkInterfaceOutcomeReceiver proxy = makeNetworkInterfaceOutcomeReceiver(
+                executor, callback);
+        try {
+            mService.connectNetwork(iface, proxy);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Disable a network interface.
+     *
+     * Disables the use of a network interface to fulfill network requests. If the interface
+     * currently serves a request, the network will be torn down.
+     * This function accepts an {@link OutcomeReceiver} that is called once the operation has
+     * finished execution.
+     *
+     * @param iface the name of the interface to disable.
+     * @param executor an {@link Executor} to execute the callback on. Optional if callback is null.
+     * @param callback an optional {@link OutcomeReceiver} to listen for completion of the
+     *                 operation. On success, {@link OutcomeReceiver#onResult} is called with the
+     *                 interface name. On error, {@link OutcomeReceiver#onError} is called with more
+     *                 information about the error.
+     * @throws SecurityException if the process doesn't hold
+     *                          {@link android.Manifest.permission.MANAGE_ETHERNET_NETWORKS}.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK,
+            android.Manifest.permission.MANAGE_ETHERNET_NETWORKS})
+    @RequiresFeature(PackageManager.FEATURE_AUTOMOTIVE)
+    public void disableInterface(
+            @NonNull String iface,
+            @Nullable @CallbackExecutor Executor executor,
+            @Nullable OutcomeReceiver<String, EthernetNetworkManagementException> callback) {
+        Objects.requireNonNull(iface, "iface must be non-null");
+        final NetworkInterfaceOutcomeReceiver proxy = makeNetworkInterfaceOutcomeReceiver(
+                executor, callback);
+        try {
+            mService.disconnectNetwork(iface, proxy);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Change ethernet setting.
+     *
+     * @param enabled enable or disable ethernet settings.
+     *
+     * @hide
+     */
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK,
+            android.Manifest.permission.NETWORK_SETTINGS})
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void setEthernetEnabled(boolean enabled) {
+        try {
+            mService.setEthernetEnabled(enabled);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Listen to changes in the state of ethernet.
+     *
+     * @param executor to run callbacks on.
+     * @param listener to listen ethernet state changed.
+     *
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void addEthernetStateListener(@NonNull Executor executor,
+            @NonNull IntConsumer listener) {
+        Objects.requireNonNull(executor);
+        Objects.requireNonNull(listener);
+        synchronized (mListenerLock) {
+            maybeAddServiceListener();
+            mEthernetStateListeners.add(new ListenerInfo<IntConsumer>(executor, listener));
+        }
+    }
+
+    /**
+     * Removes a listener.
+     *
+     * @param listener to listen ethernet state changed.
+     *
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    @SystemApi(client = MODULE_LIBRARIES)
+    public void removeEthernetStateListener(@NonNull IntConsumer listener) {
+        Objects.requireNonNull(listener);
+        synchronized (mListenerLock) {
+            mEthernetStateListeners.removeIf(l -> l.listener == listener);
+            maybeRemoveServiceListener();
+        }
+    }
+
+    /**
+     * Returns an array of existing Ethernet interface names regardless whether the interface
+     * is available or not currently.
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    @SystemApi(client = MODULE_LIBRARIES)
+    @NonNull
+    public List<String> getInterfaceList() {
+        try {
+            return mService.getInterfaceList();
+        } catch (RemoteException e) {
+            throw e.rethrowAsRuntimeException();
+        }
+    }
+}
diff --git a/framework-t/src/android/net/EthernetNetworkManagementException.aidl b/framework-t/src/android/net/EthernetNetworkManagementException.aidl
new file mode 100644
index 0000000..adf9e5a
--- /dev/null
+++ b/framework-t/src/android/net/EthernetNetworkManagementException.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ package android.net;
+
+ parcelable EthernetNetworkManagementException;
\ No newline at end of file
diff --git a/framework-t/src/android/net/EthernetNetworkManagementException.java b/framework-t/src/android/net/EthernetNetworkManagementException.java
new file mode 100644
index 0000000..a69cc55
--- /dev/null
+++ b/framework-t/src/android/net/EthernetNetworkManagementException.java
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.Objects;
+
+/** @hide */
+@SystemApi
+public final class EthernetNetworkManagementException
+        extends RuntimeException implements Parcelable {
+
+    /* @hide */
+    public EthernetNetworkManagementException(@NonNull final String errorMessage) {
+        super(errorMessage);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getMessage());
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj == null || getClass() != obj.getClass()) return false;
+        final EthernetNetworkManagementException that = (EthernetNetworkManagementException) obj;
+
+        return Objects.equals(getMessage(), that.getMessage());
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeString(getMessage());
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @NonNull
+    public static final Parcelable.Creator<EthernetNetworkManagementException> CREATOR =
+            new Parcelable.Creator<EthernetNetworkManagementException>() {
+                @Override
+                public EthernetNetworkManagementException[] newArray(int size) {
+                    return new EthernetNetworkManagementException[size];
+                }
+
+                @Override
+                public EthernetNetworkManagementException createFromParcel(@NonNull Parcel source) {
+                    return new EthernetNetworkManagementException(source.readString());
+                }
+            };
+}
diff --git a/framework-t/src/android/net/EthernetNetworkSpecifier.java b/framework-t/src/android/net/EthernetNetworkSpecifier.java
new file mode 100644
index 0000000..e4d6e24
--- /dev/null
+++ b/framework-t/src/android/net/EthernetNetworkSpecifier.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.text.TextUtils;
+
+import java.util.Objects;
+
+/**
+ * A {@link NetworkSpecifier} used to identify ethernet interfaces.
+ *
+ * @see EthernetManager
+ */
+public final class EthernetNetworkSpecifier extends NetworkSpecifier implements Parcelable {
+
+    /**
+     * Name of the network interface.
+     */
+    @NonNull
+    private final String mInterfaceName;
+
+    /**
+     * Create a new EthernetNetworkSpecifier.
+     * @param interfaceName Name of the ethernet interface the specifier refers to.
+     */
+    public EthernetNetworkSpecifier(@NonNull String interfaceName) {
+        if (TextUtils.isEmpty(interfaceName)) {
+            throw new IllegalArgumentException();
+        }
+        mInterfaceName = interfaceName;
+    }
+
+    /**
+     * Get the name of the ethernet interface the specifier refers to.
+     */
+    @Nullable
+    public String getInterfaceName() {
+        // This may be null in the future to support specifiers based on data other than the
+        // interface name.
+        return mInterfaceName;
+    }
+
+    /** @hide */
+    @Override
+    public boolean canBeSatisfiedBy(@Nullable NetworkSpecifier other) {
+        return equals(other);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object o) {
+        if (!(o instanceof EthernetNetworkSpecifier)) return false;
+        return TextUtils.equals(mInterfaceName, ((EthernetNetworkSpecifier) o).mInterfaceName);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(mInterfaceName);
+    }
+
+    @Override
+    public String toString() {
+        return "EthernetNetworkSpecifier (" + mInterfaceName + ")";
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeString(mInterfaceName);
+    }
+
+    public static final @NonNull Parcelable.Creator<EthernetNetworkSpecifier> CREATOR =
+            new Parcelable.Creator<EthernetNetworkSpecifier>() {
+        public EthernetNetworkSpecifier createFromParcel(Parcel in) {
+            return new EthernetNetworkSpecifier(in.readString());
+        }
+        public EthernetNetworkSpecifier[] newArray(int size) {
+            return new EthernetNetworkSpecifier[size];
+        }
+    };
+}
diff --git a/framework-t/src/android/net/EthernetNetworkUpdateRequest.aidl b/framework-t/src/android/net/EthernetNetworkUpdateRequest.aidl
new file mode 100644
index 0000000..debc348
--- /dev/null
+++ b/framework-t/src/android/net/EthernetNetworkUpdateRequest.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ package android.net;
+
+ parcelable EthernetNetworkUpdateRequest;
\ No newline at end of file
diff --git a/framework-t/src/android/net/EthernetNetworkUpdateRequest.java b/framework-t/src/android/net/EthernetNetworkUpdateRequest.java
new file mode 100644
index 0000000..1691942
--- /dev/null
+++ b/framework-t/src/android/net/EthernetNetworkUpdateRequest.java
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.Objects;
+
+/**
+ * Represents a request to update an existing Ethernet interface.
+ *
+ * @see EthernetManager#updateConfiguration
+ *
+ * @hide
+ */
+@SystemApi
+public final class EthernetNetworkUpdateRequest implements Parcelable {
+    @Nullable
+    private final IpConfiguration mIpConfig;
+    @Nullable
+    private final NetworkCapabilities mNetworkCapabilities;
+
+    /**
+     * Setting the {@link IpConfiguration} is optional in {@link EthernetNetworkUpdateRequest}.
+     * When set to null, the existing IpConfiguration is not updated.
+     *
+     * @return the new {@link IpConfiguration} or null.
+     */
+    @Nullable
+    public IpConfiguration getIpConfiguration() {
+        return mIpConfig == null ? null : new IpConfiguration(mIpConfig);
+    }
+
+    /**
+     * Setting the {@link NetworkCapabilities} is optional in {@link EthernetNetworkUpdateRequest}.
+     * When set to null, the existing NetworkCapabilities are not updated.
+     *
+     * @return the new {@link NetworkCapabilities} or null.
+     */
+    @Nullable
+    public NetworkCapabilities getNetworkCapabilities() {
+        return mNetworkCapabilities == null ? null : new NetworkCapabilities(mNetworkCapabilities);
+    }
+
+    private EthernetNetworkUpdateRequest(@Nullable final IpConfiguration ipConfig,
+            @Nullable final NetworkCapabilities networkCapabilities) {
+        mIpConfig = ipConfig;
+        mNetworkCapabilities = networkCapabilities;
+    }
+
+    private EthernetNetworkUpdateRequest(@NonNull final Parcel source) {
+        Objects.requireNonNull(source);
+        mIpConfig = source.readParcelable(IpConfiguration.class.getClassLoader(),
+                IpConfiguration.class);
+        mNetworkCapabilities = source.readParcelable(NetworkCapabilities.class.getClassLoader(),
+                NetworkCapabilities.class);
+    }
+
+    /**
+     * Builder used to create {@link EthernetNetworkUpdateRequest} objects.
+     */
+    public static final class Builder {
+        @Nullable
+        private IpConfiguration mBuilderIpConfig;
+        @Nullable
+        private NetworkCapabilities mBuilderNetworkCapabilities;
+
+        public Builder(){}
+
+        /**
+         * Constructor to populate the builder's values with an already built
+         * {@link EthernetNetworkUpdateRequest}.
+         * @param request the {@link EthernetNetworkUpdateRequest} to populate with.
+         */
+        public Builder(@NonNull final EthernetNetworkUpdateRequest request) {
+            Objects.requireNonNull(request);
+            mBuilderIpConfig = null == request.mIpConfig
+                    ? null : new IpConfiguration(request.mIpConfig);
+            mBuilderNetworkCapabilities = null == request.mNetworkCapabilities
+                    ? null : new NetworkCapabilities(request.mNetworkCapabilities);
+        }
+
+        /**
+         * Set the {@link IpConfiguration} to be used with the {@code Builder}.
+         * @param ipConfig the {@link IpConfiguration} to set.
+         * @return The builder to facilitate chaining.
+         */
+        @NonNull
+        public Builder setIpConfiguration(@Nullable final IpConfiguration ipConfig) {
+            mBuilderIpConfig = ipConfig == null ? null : new IpConfiguration(ipConfig);
+            return this;
+        }
+
+        /**
+         * Set the {@link NetworkCapabilities} to be used with the {@code Builder}.
+         * @param nc the {@link NetworkCapabilities} to set.
+         * @return The builder to facilitate chaining.
+         */
+        @NonNull
+        public Builder setNetworkCapabilities(@Nullable final NetworkCapabilities nc) {
+            mBuilderNetworkCapabilities = nc == null ? null : new NetworkCapabilities(nc);
+            return this;
+        }
+
+        /**
+         * Build {@link EthernetNetworkUpdateRequest} return the current update request.
+         *
+         * @throws IllegalStateException when both mBuilderNetworkCapabilities and mBuilderIpConfig
+         *                               are null.
+         */
+        @NonNull
+        public EthernetNetworkUpdateRequest build() {
+            if (mBuilderIpConfig == null && mBuilderNetworkCapabilities == null) {
+                throw new IllegalStateException(
+                        "Cannot construct an empty EthernetNetworkUpdateRequest");
+            }
+            return new EthernetNetworkUpdateRequest(mBuilderIpConfig, mBuilderNetworkCapabilities);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "EthernetNetworkUpdateRequest{"
+                + "mIpConfig=" + mIpConfig
+                + ", mNetworkCapabilities=" + mNetworkCapabilities + '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        EthernetNetworkUpdateRequest that = (EthernetNetworkUpdateRequest) o;
+
+        return Objects.equals(that.getIpConfiguration(), mIpConfig)
+                && Objects.equals(that.getNetworkCapabilities(), mNetworkCapabilities);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mIpConfig, mNetworkCapabilities);
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeParcelable(mIpConfig, flags);
+        dest.writeParcelable(mNetworkCapabilities, flags);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @NonNull
+    public static final Parcelable.Creator<EthernetNetworkUpdateRequest> CREATOR =
+            new Parcelable.Creator<EthernetNetworkUpdateRequest>() {
+                @Override
+                public EthernetNetworkUpdateRequest[] newArray(int size) {
+                    return new EthernetNetworkUpdateRequest[size];
+                }
+
+                @Override
+                public EthernetNetworkUpdateRequest createFromParcel(@NonNull Parcel source) {
+                    return new EthernetNetworkUpdateRequest(source);
+                }
+            };
+}
diff --git a/framework-t/src/android/net/IEthernetManager.aidl b/framework-t/src/android/net/IEthernetManager.aidl
new file mode 100644
index 0000000..42e4c1a
--- /dev/null
+++ b/framework-t/src/android/net/IEthernetManager.aidl
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.IpConfiguration;
+import android.net.IEthernetServiceListener;
+import android.net.EthernetNetworkManagementException;
+import android.net.EthernetNetworkUpdateRequest;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.ITetheredInterfaceCallback;
+
+import java.util.List;
+
+/**
+ * Interface that answers queries about, and allows changing
+ * ethernet configuration.
+ */
+/** {@hide} */
+interface IEthernetManager
+{
+    String[] getAvailableInterfaces();
+    IpConfiguration getConfiguration(String iface);
+    void setConfiguration(String iface, in IpConfiguration config);
+    boolean isAvailable(String iface);
+    void addListener(in IEthernetServiceListener listener);
+    void removeListener(in IEthernetServiceListener listener);
+    void setIncludeTestInterfaces(boolean include);
+    void requestTetheredInterface(in ITetheredInterfaceCallback callback);
+    void releaseTetheredInterface(in ITetheredInterfaceCallback callback);
+    void updateConfiguration(String iface, in EthernetNetworkUpdateRequest request,
+        in INetworkInterfaceOutcomeReceiver listener);
+    void connectNetwork(String iface, in INetworkInterfaceOutcomeReceiver listener);
+    void disconnectNetwork(String iface, in INetworkInterfaceOutcomeReceiver listener);
+    void setEthernetEnabled(boolean enabled);
+    List<String> getInterfaceList();
+}
diff --git a/framework-t/src/android/net/IEthernetServiceListener.aidl b/framework-t/src/android/net/IEthernetServiceListener.aidl
new file mode 100644
index 0000000..751605b
--- /dev/null
+++ b/framework-t/src/android/net/IEthernetServiceListener.aidl
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.IpConfiguration;
+
+/** @hide */
+oneway interface IEthernetServiceListener
+{
+    void onEthernetStateChanged(int state);
+    void onInterfaceStateChanged(String iface, int state, int role,
+            in IpConfiguration configuration);
+}
diff --git a/framework-t/src/android/net/IIpSecService.aidl b/framework-t/src/android/net/IIpSecService.aidl
new file mode 100644
index 0000000..933256a
--- /dev/null
+++ b/framework-t/src/android/net/IIpSecService.aidl
@@ -0,0 +1,78 @@
+/*
+** Copyright 2017, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+
+package android.net;
+
+import android.net.LinkAddress;
+import android.net.Network;
+import android.net.IpSecConfig;
+import android.net.IpSecUdpEncapResponse;
+import android.net.IpSecSpiResponse;
+import android.net.IpSecTransformResponse;
+import android.net.IpSecTunnelInterfaceResponse;
+import android.os.Bundle;
+import android.os.IBinder;
+import android.os.ParcelFileDescriptor;
+
+/**
+ * @hide
+ */
+interface IIpSecService
+{
+    IpSecSpiResponse allocateSecurityParameterIndex(
+            in String destinationAddress, int requestedSpi, in IBinder binder);
+
+    void releaseSecurityParameterIndex(int resourceId);
+
+    IpSecUdpEncapResponse openUdpEncapsulationSocket(int port, in IBinder binder);
+
+    void closeUdpEncapsulationSocket(int resourceId);
+
+    IpSecTunnelInterfaceResponse createTunnelInterface(
+            in String localAddr,
+            in String remoteAddr,
+            in Network underlyingNetwork,
+            in IBinder binder,
+            in String callingPackage);
+
+    void addAddressToTunnelInterface(
+            int tunnelResourceId,
+            in LinkAddress localAddr,
+            in String callingPackage);
+
+    void removeAddressFromTunnelInterface(
+            int tunnelResourceId,
+            in LinkAddress localAddr,
+            in String callingPackage);
+
+    void setNetworkForTunnelInterface(
+            int tunnelResourceId, in Network underlyingNetwork, in String callingPackage);
+
+    void deleteTunnelInterface(int resourceId, in String callingPackage);
+
+    IpSecTransformResponse createTransform(
+            in IpSecConfig c, in IBinder binder, in String callingPackage);
+
+    void deleteTransform(int transformId);
+
+    void applyTransportModeTransform(
+            in ParcelFileDescriptor socket, int direction, int transformId);
+
+    void applyTunnelModeTransform(
+            int tunnelResourceId, int direction, int transformResourceId, in String callingPackage);
+
+    void removeTransportModeTransforms(in ParcelFileDescriptor socket);
+}
diff --git a/framework-t/src/android/net/INetworkInterfaceOutcomeReceiver.aidl b/framework-t/src/android/net/INetworkInterfaceOutcomeReceiver.aidl
new file mode 100644
index 0000000..85795ea
--- /dev/null
+++ b/framework-t/src/android/net/INetworkInterfaceOutcomeReceiver.aidl
@@ -0,0 +1,25 @@
+/**
+ * Copyright (c) 2021, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.EthernetNetworkManagementException;
+
+/** @hide */
+oneway interface INetworkInterfaceOutcomeReceiver {
+    void onResult(in String iface);
+    void onError(in EthernetNetworkManagementException e);
+}
\ No newline at end of file
diff --git a/framework-t/src/android/net/INetworkStatsService.aidl b/framework-t/src/android/net/INetworkStatsService.aidl
new file mode 100644
index 0000000..c86f7fd
--- /dev/null
+++ b/framework-t/src/android/net/INetworkStatsService.aidl
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.DataUsageRequest;
+import android.net.INetworkStatsSession;
+import android.net.Network;
+import android.net.NetworkStateSnapshot;
+import android.net.NetworkStats;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.UnderlyingNetworkInfo;
+import android.net.netstats.IUsageCallback;
+import android.net.netstats.provider.INetworkStatsProvider;
+import android.net.netstats.provider.INetworkStatsProviderCallback;
+import android.os.IBinder;
+import android.os.Messenger;
+
+/** {@hide} */
+interface INetworkStatsService {
+
+    /** Start a statistics query session. */
+    @UnsupportedAppUsage
+    INetworkStatsSession openSession();
+
+    /** Start a statistics query session. If calling package is profile or device owner then it is
+     *  granted automatic access if apiLevel is NetworkStatsManager.API_LEVEL_DPC_ALLOWED. If
+     *  apiLevel is at least NetworkStatsManager.API_LEVEL_REQUIRES_PACKAGE_USAGE_STATS then
+     *  PACKAGE_USAGE_STATS permission is always checked. If PACKAGE_USAGE_STATS is not granted
+     *  READ_NETWORK_USAGE_STATS is checked for.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = 30, trackingBug = 170729553)
+    INetworkStatsSession openSessionForUsageStats(int flags, String callingPackage);
+
+    /** Return data layer snapshot of UID network usage. */
+    @UnsupportedAppUsage
+    NetworkStats getDataLayerSnapshotForUid(int uid);
+
+    /** Get the transport NetworkStats for all UIDs since boot. */
+    NetworkStats getUidStatsForTransport(int transport);
+
+    /** Return set of any ifaces associated with mobile networks since boot. */
+    @UnsupportedAppUsage
+    String[] getMobileIfaces();
+
+    /** Increment data layer count of operations performed for UID and tag. */
+    void incrementOperationCount(int uid, int tag, int operationCount);
+
+    /**  Notify {@code NetworkStatsService} about network status changed. */
+    void notifyNetworkStatus(
+         in Network[] defaultNetworks,
+         in NetworkStateSnapshot[] snapshots,
+         in String activeIface,
+         in UnderlyingNetworkInfo[] underlyingNetworkInfos);
+    /** Force update of statistics. */
+    @UnsupportedAppUsage
+    void forceUpdate();
+
+    /** Registers a callback on data usage. */
+    DataUsageRequest registerUsageCallback(String callingPackage,
+            in DataUsageRequest request, in IUsageCallback callback);
+
+    /** Unregisters a callback on data usage. */
+    void unregisterUsageRequest(in DataUsageRequest request);
+
+    /** Get the uid stats information since boot */
+    long getUidStats(int uid, int type);
+
+    /** Get the iface stats information since boot */
+    long getIfaceStats(String iface, int type);
+
+    /** Get the total network stats information since boot */
+    long getTotalStats(int type);
+
+    /** Registers a network stats provider */
+    INetworkStatsProviderCallback registerNetworkStatsProvider(String tag,
+            in INetworkStatsProvider provider);
+
+    /** Mark given UID as being in foreground for stats purposes. */
+    void noteUidForeground(int uid, boolean uidForeground);
+
+    /** Advise persistence threshold; may be overridden internally. */
+    void advisePersistThreshold(long thresholdBytes);
+
+    /**
+     * Set the warning and limit to all registered custom network stats providers.
+     * Note that invocation of any interface will be sent to all providers.
+     */
+     void setStatsProviderWarningAndLimitAsync(String iface, long warning, long limit);
+}
diff --git a/framework-t/src/android/net/INetworkStatsSession.aidl b/framework-t/src/android/net/INetworkStatsSession.aidl
new file mode 100644
index 0000000..ab70be8
--- /dev/null
+++ b/framework-t/src/android/net/INetworkStatsSession.aidl
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.NetworkStats;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+
+/** {@hide} */
+interface INetworkStatsSession {
+
+    /** Return device aggregated network layer usage summary for traffic that matches template. */
+    NetworkStats getDeviceSummaryForNetwork(in NetworkTemplate template, long start, long end);
+
+    /** Return network layer usage summary for traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStats getSummaryForNetwork(in NetworkTemplate template, long start, long end);
+    /** Return historical network layer stats for traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStatsHistory getHistoryForNetwork(in NetworkTemplate template, int fields);
+    /**
+     * Return historical network layer stats for traffic that matches template, start and end
+     * timestamp.
+     */
+    NetworkStatsHistory getHistoryIntervalForNetwork(in NetworkTemplate template, int fields, long start, long end);
+
+    /**
+     * Return network layer usage summary per UID for traffic that matches template.
+     *
+     * <p>The resulting {@code NetworkStats#getElapsedRealtime()} contains time delta between
+     * {@code start} and {@code end}.
+     *
+     * @param template - a predicate to filter netstats.
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param includeTags - includes data usage tags if true.
+     */
+    @UnsupportedAppUsage
+    NetworkStats getSummaryForAllUid(in NetworkTemplate template, long start, long end, boolean includeTags);
+
+    /** Return network layer usage summary per UID for tagged traffic that matches template. */
+    NetworkStats getTaggedSummaryForAllUid(in NetworkTemplate template, long start, long end);
+
+    /** Return historical network layer stats for specific UID traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStatsHistory getHistoryForUid(in NetworkTemplate template, int uid, int set, int tag, int fields);
+    /** Return historical network layer stats for specific UID traffic that matches template. */
+    NetworkStatsHistory getHistoryIntervalForUid(in NetworkTemplate template, int uid, int set, int tag, int fields, long start, long end);
+
+    /** Return array of uids that have stats and are accessible to the calling user */
+    int[] getRelevantUids();
+
+    @UnsupportedAppUsage
+    void close();
+
+}
diff --git a/framework-t/src/android/net/ITetheredInterfaceCallback.aidl b/framework-t/src/android/net/ITetheredInterfaceCallback.aidl
new file mode 100644
index 0000000..14aa023
--- /dev/null
+++ b/framework-t/src/android/net/ITetheredInterfaceCallback.aidl
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+oneway interface ITetheredInterfaceCallback {
+    void onAvailable(in String iface);
+    void onUnavailable();
+}
\ No newline at end of file
diff --git a/framework-t/src/android/net/IpSecAlgorithm.java b/framework-t/src/android/net/IpSecAlgorithm.java
new file mode 100644
index 0000000..10a22ac
--- /dev/null
+++ b/framework-t/src/android/net/IpSecAlgorithm.java
@@ -0,0 +1,491 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.annotation.NonNull;
+import android.annotation.StringDef;
+import android.content.res.Resources;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+/**
+ * This class represents a single algorithm that can be used by an {@link IpSecTransform}.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4301">RFC 4301, Security Architecture for the
+ * Internet Protocol</a>
+ */
+public final class IpSecAlgorithm implements Parcelable {
+    private static final String TAG = "IpSecAlgorithm";
+
+    /**
+     * Null cipher.
+     *
+     * @hide
+     */
+    public static final String CRYPT_NULL = "ecb(cipher_null)";
+
+    /**
+     * AES-CBC Encryption/Ciphering Algorithm.
+     *
+     * <p>Valid lengths for this key are {128, 192, 256}.
+     */
+    public static final String CRYPT_AES_CBC = "cbc(aes)";
+
+    /**
+     * AES-CTR Encryption/Ciphering Algorithm.
+     *
+     * <p>Valid lengths for keying material are {160, 224, 288}.
+     *
+     * <p>As per <a href="https://tools.ietf.org/html/rfc3686#section-5.1">RFC3686 (Section
+     * 5.1)</a>, keying material consists of a 128, 192, or 256 bit AES key followed by a 32-bit
+     * nonce. RFC compliance requires that the nonce must be unique per security association.
+     *
+     * <p>This algorithm may be available on the device. Caller MUST check if it is supported before
+     * using it by calling {@link #getSupportedAlgorithms()} and checking if this algorithm is
+     * included in the returned algorithm set. The returned algorithm set will not change unless the
+     * device is rebooted. {@link IllegalArgumentException} will be thrown if this algorithm is
+     * requested on an unsupported device.
+     *
+     * <p>@see {@link #getSupportedAlgorithms()}
+     */
+    // This algorithm may be available on devices released before Android 12, and is guaranteed
+    // to be available on devices first shipped with Android 12 or later.
+    public static final String CRYPT_AES_CTR = "rfc3686(ctr(aes))";
+
+    /**
+     * MD5 HMAC Authentication/Integrity Algorithm. <b>This algorithm is not recommended for use in
+     * new applications and is provided for legacy compatibility with 3gpp infrastructure.</b>
+     *
+     * <p>Keys for this algorithm must be 128 bits in length.
+     *
+     * <p>Valid truncation lengths are multiples of 8 bits from 96 to 128.
+     */
+    public static final String AUTH_HMAC_MD5 = "hmac(md5)";
+
+    /**
+     * SHA1 HMAC Authentication/Integrity Algorithm. <b>This algorithm is not recommended for use in
+     * new applications and is provided for legacy compatibility with 3gpp infrastructure.</b>
+     *
+     * <p>Keys for this algorithm must be 160 bits in length.
+     *
+     * <p>Valid truncation lengths are multiples of 8 bits from 96 to 160.
+     */
+    public static final String AUTH_HMAC_SHA1 = "hmac(sha1)";
+
+    /**
+     * SHA256 HMAC Authentication/Integrity Algorithm.
+     *
+     * <p>Keys for this algorithm must be 256 bits in length.
+     *
+     * <p>Valid truncation lengths are multiples of 8 bits from 96 to 256.
+     */
+    public static final String AUTH_HMAC_SHA256 = "hmac(sha256)";
+
+    /**
+     * SHA384 HMAC Authentication/Integrity Algorithm.
+     *
+     * <p>Keys for this algorithm must be 384 bits in length.
+     *
+     * <p>Valid truncation lengths are multiples of 8 bits from 192 to 384.
+     */
+    public static final String AUTH_HMAC_SHA384 = "hmac(sha384)";
+
+    /**
+     * SHA512 HMAC Authentication/Integrity Algorithm.
+     *
+     * <p>Keys for this algorithm must be 512 bits in length.
+     *
+     * <p>Valid truncation lengths are multiples of 8 bits from 256 to 512.
+     */
+    public static final String AUTH_HMAC_SHA512 = "hmac(sha512)";
+
+    /**
+     * AES-XCBC Authentication/Integrity Algorithm.
+     *
+     * <p>Keys for this algorithm must be 128 bits in length.
+     *
+     * <p>The only valid truncation length is 96 bits.
+     *
+     * <p>This algorithm may be available on the device. Caller MUST check if it is supported before
+     * using it by calling {@link #getSupportedAlgorithms()} and checking if this algorithm is
+     * included in the returned algorithm set. The returned algorithm set will not change unless the
+     * device is rebooted. {@link IllegalArgumentException} will be thrown if this algorithm is
+     * requested on an unsupported device.
+     *
+     * <p>@see {@link #getSupportedAlgorithms()}
+     */
+    // This algorithm may be available on devices released before Android 12, and is guaranteed
+    // to be available on devices first shipped with Android 12 or later.
+    public static final String AUTH_AES_XCBC = "xcbc(aes)";
+
+    /**
+     * AES-CMAC Authentication/Integrity Algorithm.
+     *
+     * <p>Keys for this algorithm must be 128 bits in length.
+     *
+     * <p>The only valid truncation length is 96 bits.
+     *
+     * <p>This algorithm may be available on the device. Caller MUST check if it is supported before
+     * using it by calling {@link #getSupportedAlgorithms()} and checking if this algorithm is
+     * included in the returned algorithm set. The returned algorithm set will not change unless the
+     * device is rebooted. {@link IllegalArgumentException} will be thrown if this algorithm is
+     * requested on an unsupported device.
+     *
+     * <p>@see {@link #getSupportedAlgorithms()}
+     */
+    // This algorithm may be available on devices released before Android 12, and is guaranteed
+    // to be available on devices first shipped with Android 12 or later.
+    public static final String AUTH_AES_CMAC = "cmac(aes)";
+
+    /**
+     * AES-GCM Authentication/Integrity + Encryption/Ciphering Algorithm.
+     *
+     * <p>Valid lengths for keying material are {160, 224, 288}.
+     *
+     * <p>As per <a href="https://tools.ietf.org/html/rfc4106#section-8.1">RFC4106 (Section
+     * 8.1)</a>, keying material consists of a 128, 192, or 256 bit AES key followed by a 32-bit
+     * salt. RFC compliance requires that the salt must be unique per invocation with the same key.
+     *
+     * <p>Valid ICV (truncation) lengths are {64, 96, 128}.
+     */
+    public static final String AUTH_CRYPT_AES_GCM = "rfc4106(gcm(aes))";
+
+    /**
+     * ChaCha20-Poly1305 Authentication/Integrity + Encryption/Ciphering Algorithm.
+     *
+     * <p>Keys for this algorithm must be 288 bits in length.
+     *
+     * <p>As per <a href="https://tools.ietf.org/html/rfc7634#section-2">RFC7634 (Section 2)</a>,
+     * keying material consists of a 256 bit key followed by a 32-bit salt. The salt is fixed per
+     * security association.
+     *
+     * <p>The only valid ICV (truncation) length is 128 bits.
+     *
+     * <p>This algorithm may be available on the device. Caller MUST check if it is supported before
+     * using it by calling {@link #getSupportedAlgorithms()} and checking if this algorithm is
+     * included in the returned algorithm set. The returned algorithm set will not change unless the
+     * device is rebooted. {@link IllegalArgumentException} will be thrown if this algorithm is
+     * requested on an unsupported device.
+     *
+     * <p>@see {@link #getSupportedAlgorithms()}
+     */
+    // This algorithm may be available on devices released before Android 12, and is guaranteed
+    // to be available on devices first shipped with Android 12 or later.
+    public static final String AUTH_CRYPT_CHACHA20_POLY1305 = "rfc7539esp(chacha20,poly1305)";
+
+    /** @hide */
+    @StringDef({
+        CRYPT_AES_CBC,
+        CRYPT_AES_CTR,
+        AUTH_HMAC_MD5,
+        AUTH_HMAC_SHA1,
+        AUTH_HMAC_SHA256,
+        AUTH_HMAC_SHA384,
+        AUTH_HMAC_SHA512,
+        AUTH_AES_XCBC,
+        AUTH_AES_CMAC,
+        AUTH_CRYPT_AES_GCM,
+        AUTH_CRYPT_CHACHA20_POLY1305
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface AlgorithmName {}
+
+    /** @hide */
+    @VisibleForTesting
+    public static final Map<String, Integer> ALGO_TO_REQUIRED_FIRST_SDK = new HashMap<>();
+
+    private static final int SDK_VERSION_ZERO = 0;
+
+    static {
+        ALGO_TO_REQUIRED_FIRST_SDK.put(CRYPT_AES_CBC, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_HMAC_MD5, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_HMAC_SHA1, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_HMAC_SHA256, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_HMAC_SHA384, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_HMAC_SHA512, SDK_VERSION_ZERO);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_CRYPT_AES_GCM, SDK_VERSION_ZERO);
+
+        ALGO_TO_REQUIRED_FIRST_SDK.put(CRYPT_AES_CTR, Build.VERSION_CODES.S);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_AES_XCBC, Build.VERSION_CODES.S);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_AES_CMAC, Build.VERSION_CODES.S);
+        ALGO_TO_REQUIRED_FIRST_SDK.put(AUTH_CRYPT_CHACHA20_POLY1305, Build.VERSION_CODES.S);
+    }
+
+    private static final Set<String> ENABLED_ALGOS =
+            Collections.unmodifiableSet(loadAlgos(Resources.getSystem()));
+
+    private final String mName;
+    private final byte[] mKey;
+    private final int mTruncLenBits;
+
+    /**
+     * Creates an IpSecAlgorithm of one of the supported types. Supported algorithm names are
+     * defined as constants in this class.
+     *
+     * <p>For algorithms that produce an integrity check value, the truncation length is a required
+     * parameter. See {@link #IpSecAlgorithm(String algorithm, byte[] key, int truncLenBits)}
+     *
+     * @param algorithm name of the algorithm.
+     * @param key key padded to a multiple of 8 bits.
+     * @throws IllegalArgumentException if algorithm or key length is invalid.
+     */
+    public IpSecAlgorithm(@NonNull @AlgorithmName String algorithm, @NonNull byte[] key) {
+        this(algorithm, key, 0);
+    }
+
+    /**
+     * Creates an IpSecAlgorithm of one of the supported types. Supported algorithm names are
+     * defined as constants in this class.
+     *
+     * <p>This constructor only supports algorithms that use a truncation length. i.e.
+     * Authentication and Authenticated Encryption algorithms.
+     *
+     * @param algorithm name of the algorithm.
+     * @param key key padded to a multiple of 8 bits.
+     * @param truncLenBits number of bits of output hash to use.
+     * @throws IllegalArgumentException if algorithm, key length or truncation length is invalid.
+     */
+    public IpSecAlgorithm(
+            @NonNull @AlgorithmName String algorithm, @NonNull byte[] key, int truncLenBits) {
+        mName = algorithm;
+        mKey = key.clone();
+        mTruncLenBits = truncLenBits;
+        checkValidOrThrow(mName, mKey.length * 8, mTruncLenBits);
+    }
+
+    /** Get the algorithm name */
+    @NonNull
+    public String getName() {
+        return mName;
+    }
+
+    /** Get the key for this algorithm */
+    @NonNull
+    public byte[] getKey() {
+        return mKey.clone();
+    }
+
+    /** Get the truncation length of this algorithm, in bits */
+    public int getTruncationLengthBits() {
+        return mTruncLenBits;
+    }
+
+    /** Parcelable Implementation */
+    public int describeContents() {
+        return 0;
+    }
+
+    /** Write to parcel */
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeString(mName);
+        out.writeByteArray(mKey);
+        out.writeInt(mTruncLenBits);
+    }
+
+    /** Parcelable Creator */
+    public static final @android.annotation.NonNull Parcelable.Creator<IpSecAlgorithm> CREATOR =
+            new Parcelable.Creator<IpSecAlgorithm>() {
+                public IpSecAlgorithm createFromParcel(Parcel in) {
+                    final String name = in.readString();
+                    final byte[] key = in.createByteArray();
+                    final int truncLenBits = in.readInt();
+
+                    return new IpSecAlgorithm(name, key, truncLenBits);
+                }
+
+                public IpSecAlgorithm[] newArray(int size) {
+                    return new IpSecAlgorithm[size];
+                }
+            };
+
+    /**
+     * Returns supported IPsec algorithms for the current device.
+     *
+     * <p>Some algorithms may not be supported on old devices. Callers MUST check if an algorithm is
+     * supported before using it.
+     */
+    @NonNull
+    public static Set<String> getSupportedAlgorithms() {
+        return ENABLED_ALGOS;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public static Set<String> loadAlgos(Resources systemResources) {
+        final Set<String> enabledAlgos = new HashSet<>();
+
+        // Load and validate the optional algorithm resource. Undefined or duplicate algorithms in
+        // the resource are not allowed.
+        final String[] resourceAlgos = systemResources.getStringArray(
+                android.R.array.config_optionalIpSecAlgorithms);
+        for (String str : resourceAlgos) {
+            if (!ALGO_TO_REQUIRED_FIRST_SDK.containsKey(str) || !enabledAlgos.add(str)) {
+                // This error should be caught by CTS and never be thrown to API callers
+                throw new IllegalArgumentException("Invalid or repeated algorithm " + str);
+            }
+        }
+
+        for (Entry<String, Integer> entry : ALGO_TO_REQUIRED_FIRST_SDK.entrySet()) {
+            if (Build.VERSION.DEVICE_INITIAL_SDK_INT >= entry.getValue()) {
+                enabledAlgos.add(entry.getKey());
+            }
+        }
+
+        return enabledAlgos;
+    }
+
+    private static void checkValidOrThrow(String name, int keyLen, int truncLen) {
+        final boolean isValidLen;
+        final boolean isValidTruncLen;
+
+        if (!getSupportedAlgorithms().contains(name)) {
+            throw new IllegalArgumentException("Unsupported algorithm: " + name);
+        }
+
+        switch (name) {
+            case CRYPT_AES_CBC:
+                isValidLen = keyLen == 128 || keyLen == 192 || keyLen == 256;
+                isValidTruncLen = true;
+                break;
+            case CRYPT_AES_CTR:
+                // The keying material for AES-CTR is a key plus a 32-bit salt
+                isValidLen = keyLen == 128 + 32 || keyLen == 192 + 32 || keyLen == 256 + 32;
+                isValidTruncLen = true;
+                break;
+            case AUTH_HMAC_MD5:
+                isValidLen = keyLen == 128;
+                isValidTruncLen = truncLen >= 96 && truncLen <= 128;
+                break;
+            case AUTH_HMAC_SHA1:
+                isValidLen = keyLen == 160;
+                isValidTruncLen = truncLen >= 96 && truncLen <= 160;
+                break;
+            case AUTH_HMAC_SHA256:
+                isValidLen = keyLen == 256;
+                isValidTruncLen = truncLen >= 96 && truncLen <= 256;
+                break;
+            case AUTH_HMAC_SHA384:
+                isValidLen = keyLen == 384;
+                isValidTruncLen = truncLen >= 192 && truncLen <= 384;
+                break;
+            case AUTH_HMAC_SHA512:
+                isValidLen = keyLen == 512;
+                isValidTruncLen = truncLen >= 256 && truncLen <= 512;
+                break;
+            case AUTH_AES_XCBC:
+                isValidLen = keyLen == 128;
+                isValidTruncLen = truncLen == 96;
+                break;
+            case AUTH_AES_CMAC:
+                isValidLen = keyLen == 128;
+                isValidTruncLen = truncLen == 96;
+                break;
+            case AUTH_CRYPT_AES_GCM:
+                // The keying material for GCM is a key plus a 32-bit salt
+                isValidLen = keyLen == 128 + 32 || keyLen == 192 + 32 || keyLen == 256 + 32;
+                isValidTruncLen = truncLen == 64 || truncLen == 96 || truncLen == 128;
+                break;
+            case AUTH_CRYPT_CHACHA20_POLY1305:
+                // The keying material for ChaCha20Poly1305 is a key plus a 32-bit salt
+                isValidLen = keyLen == 256 + 32;
+                isValidTruncLen = truncLen == 128;
+                break;
+            default:
+                // Should never hit here.
+                throw new IllegalArgumentException("Couldn't find an algorithm: " + name);
+        }
+
+        if (!isValidLen) {
+            throw new IllegalArgumentException("Invalid key material keyLength: " + keyLen);
+        }
+        if (!isValidTruncLen) {
+            throw new IllegalArgumentException("Invalid truncation keyLength: " + truncLen);
+        }
+    }
+
+    /** @hide */
+    public boolean isAuthentication() {
+        switch (getName()) {
+            // Fallthrough
+            case AUTH_HMAC_MD5:
+            case AUTH_HMAC_SHA1:
+            case AUTH_HMAC_SHA256:
+            case AUTH_HMAC_SHA384:
+            case AUTH_HMAC_SHA512:
+            case AUTH_AES_XCBC:
+            case AUTH_AES_CMAC:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    /** @hide */
+    public boolean isEncryption() {
+        switch (getName()) {
+            case CRYPT_AES_CBC: // fallthrough
+            case CRYPT_AES_CTR:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    /** @hide */
+    public boolean isAead() {
+        switch (getName()) {
+            case AUTH_CRYPT_AES_GCM: // fallthrough
+            case AUTH_CRYPT_CHACHA20_POLY1305:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    @Override
+    @NonNull
+    public String toString() {
+        return new StringBuilder()
+                .append("{mName=")
+                .append(mName)
+                .append(", mTruncLenBits=")
+                .append(mTruncLenBits)
+                .append("}")
+                .toString();
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public static boolean equals(IpSecAlgorithm lhs, IpSecAlgorithm rhs) {
+        if (lhs == null || rhs == null) return (lhs == rhs);
+        return (lhs.mName.equals(rhs.mName)
+                && Arrays.equals(lhs.mKey, rhs.mKey)
+                && lhs.mTruncLenBits == rhs.mTruncLenBits);
+    }
+};
diff --git a/framework-t/src/android/net/IpSecConfig.aidl b/framework-t/src/android/net/IpSecConfig.aidl
new file mode 100644
index 0000000..eaefca7
--- /dev/null
+++ b/framework-t/src/android/net/IpSecConfig.aidl
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+parcelable IpSecConfig;
diff --git a/framework-t/src/android/net/IpSecConfig.java b/framework-t/src/android/net/IpSecConfig.java
new file mode 100644
index 0000000..575c5ed
--- /dev/null
+++ b/framework-t/src/android/net/IpSecConfig.java
@@ -0,0 +1,358 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.annotation.Nullable;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+/**
+ * This class encapsulates all the configuration parameters needed to create IPsec transforms and
+ * policies.
+ *
+ * @hide
+ */
+public final class IpSecConfig implements Parcelable {
+    private static final String TAG = "IpSecConfig";
+
+    // MODE_TRANSPORT or MODE_TUNNEL
+    private int mMode = IpSecTransform.MODE_TRANSPORT;
+
+    // Preventing this from being null simplifies Java->Native binder
+    private String mSourceAddress = "";
+
+    // Preventing this from being null simplifies Java->Native binder
+    private String mDestinationAddress = "";
+
+    // The underlying Network that represents the "gateway" Network
+    // for outbound packets. It may also be used to select packets.
+    private Network mNetwork;
+
+    // Minimum requirements for identifying a transform
+    // SPI identifying the IPsec SA in packet processing
+    // and a destination IP address
+    private int mSpiResourceId = IpSecManager.INVALID_RESOURCE_ID;
+
+    // Encryption Algorithm
+    private IpSecAlgorithm mEncryption;
+
+    // Authentication Algorithm
+    private IpSecAlgorithm mAuthentication;
+
+    // Authenticated Encryption Algorithm
+    private IpSecAlgorithm mAuthenticatedEncryption;
+
+    // For tunnel mode IPv4 UDP Encapsulation
+    // IpSecTransform#ENCAP_ESP_*, such as ENCAP_ESP_OVER_UDP_IKE
+    private int mEncapType = IpSecTransform.ENCAP_NONE;
+    private int mEncapSocketResourceId = IpSecManager.INVALID_RESOURCE_ID;
+    private int mEncapRemotePort;
+
+    // An interval, in seconds between the NattKeepalive packets
+    private int mNattKeepaliveInterval;
+
+    // XFRM mark and mask; defaults to 0 (no mark/mask)
+    private int mMarkValue;
+    private int mMarkMask;
+
+    // XFRM interface id
+    private int mXfrmInterfaceId;
+
+    /** Set the mode for this IPsec transform */
+    public void setMode(int mode) {
+        mMode = mode;
+    }
+
+    /** Set the source IP addres for this IPsec transform */
+    public void setSourceAddress(String sourceAddress) {
+        mSourceAddress = sourceAddress;
+    }
+
+    /** Set the destination IP address for this IPsec transform */
+    public void setDestinationAddress(String destinationAddress) {
+        mDestinationAddress = destinationAddress;
+    }
+
+    /** Set the SPI by resource ID */
+    public void setSpiResourceId(int resourceId) {
+        mSpiResourceId = resourceId;
+    }
+
+    /** Set the encryption algorithm */
+    public void setEncryption(IpSecAlgorithm encryption) {
+        mEncryption = encryption;
+    }
+
+    /** Set the authentication algorithm */
+    public void setAuthentication(IpSecAlgorithm authentication) {
+        mAuthentication = authentication;
+    }
+
+    /** Set the authenticated encryption algorithm */
+    public void setAuthenticatedEncryption(IpSecAlgorithm authenticatedEncryption) {
+        mAuthenticatedEncryption = authenticatedEncryption;
+    }
+
+    /** Set the underlying network that will carry traffic for this transform */
+    public void setNetwork(Network network) {
+        mNetwork = network;
+    }
+
+    public void setEncapType(int encapType) {
+        mEncapType = encapType;
+    }
+
+    public void setEncapSocketResourceId(int resourceId) {
+        mEncapSocketResourceId = resourceId;
+    }
+
+    public void setEncapRemotePort(int port) {
+        mEncapRemotePort = port;
+    }
+
+    public void setNattKeepaliveInterval(int interval) {
+        mNattKeepaliveInterval = interval;
+    }
+
+    /**
+     * Sets the mark value
+     *
+     * <p>Internal (System server) use only. Marks passed in by users will be overwritten or
+     * ignored.
+     */
+    public void setMarkValue(int mark) {
+        mMarkValue = mark;
+    }
+
+    /**
+     * Sets the mark mask
+     *
+     * <p>Internal (System server) use only. Marks passed in by users will be overwritten or
+     * ignored.
+     */
+    public void setMarkMask(int mask) {
+        mMarkMask = mask;
+    }
+
+    public void setXfrmInterfaceId(int xfrmInterfaceId) {
+        mXfrmInterfaceId = xfrmInterfaceId;
+    }
+
+    // Transport or Tunnel
+    public int getMode() {
+        return mMode;
+    }
+
+    public String getSourceAddress() {
+        return mSourceAddress;
+    }
+
+    public int getSpiResourceId() {
+        return mSpiResourceId;
+    }
+
+    public String getDestinationAddress() {
+        return mDestinationAddress;
+    }
+
+    public IpSecAlgorithm getEncryption() {
+        return mEncryption;
+    }
+
+    public IpSecAlgorithm getAuthentication() {
+        return mAuthentication;
+    }
+
+    public IpSecAlgorithm getAuthenticatedEncryption() {
+        return mAuthenticatedEncryption;
+    }
+
+    public Network getNetwork() {
+        return mNetwork;
+    }
+
+    public int getEncapType() {
+        return mEncapType;
+    }
+
+    public int getEncapSocketResourceId() {
+        return mEncapSocketResourceId;
+    }
+
+    public int getEncapRemotePort() {
+        return mEncapRemotePort;
+    }
+
+    public int getNattKeepaliveInterval() {
+        return mNattKeepaliveInterval;
+    }
+
+    public int getMarkValue() {
+        return mMarkValue;
+    }
+
+    public int getMarkMask() {
+        return mMarkMask;
+    }
+
+    public int getXfrmInterfaceId() {
+        return mXfrmInterfaceId;
+    }
+
+    // Parcelable Methods
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(mMode);
+        out.writeString(mSourceAddress);
+        out.writeString(mDestinationAddress);
+        out.writeParcelable(mNetwork, flags);
+        out.writeInt(mSpiResourceId);
+        out.writeParcelable(mEncryption, flags);
+        out.writeParcelable(mAuthentication, flags);
+        out.writeParcelable(mAuthenticatedEncryption, flags);
+        out.writeInt(mEncapType);
+        out.writeInt(mEncapSocketResourceId);
+        out.writeInt(mEncapRemotePort);
+        out.writeInt(mNattKeepaliveInterval);
+        out.writeInt(mMarkValue);
+        out.writeInt(mMarkMask);
+        out.writeInt(mXfrmInterfaceId);
+    }
+
+    @VisibleForTesting
+    public IpSecConfig() {}
+
+    /** Copy constructor */
+    @VisibleForTesting
+    public IpSecConfig(IpSecConfig c) {
+        mMode = c.mMode;
+        mSourceAddress = c.mSourceAddress;
+        mDestinationAddress = c.mDestinationAddress;
+        mNetwork = c.mNetwork;
+        mSpiResourceId = c.mSpiResourceId;
+        mEncryption = c.mEncryption;
+        mAuthentication = c.mAuthentication;
+        mAuthenticatedEncryption = c.mAuthenticatedEncryption;
+        mEncapType = c.mEncapType;
+        mEncapSocketResourceId = c.mEncapSocketResourceId;
+        mEncapRemotePort = c.mEncapRemotePort;
+        mNattKeepaliveInterval = c.mNattKeepaliveInterval;
+        mMarkValue = c.mMarkValue;
+        mMarkMask = c.mMarkMask;
+        mXfrmInterfaceId = c.mXfrmInterfaceId;
+    }
+
+    private IpSecConfig(Parcel in) {
+        mMode = in.readInt();
+        mSourceAddress = in.readString();
+        mDestinationAddress = in.readString();
+        mNetwork = (Network) in.readParcelable(Network.class.getClassLoader());
+        mSpiResourceId = in.readInt();
+        mEncryption =
+                (IpSecAlgorithm) in.readParcelable(IpSecAlgorithm.class.getClassLoader());
+        mAuthentication =
+                (IpSecAlgorithm) in.readParcelable(IpSecAlgorithm.class.getClassLoader());
+        mAuthenticatedEncryption =
+                (IpSecAlgorithm) in.readParcelable(IpSecAlgorithm.class.getClassLoader());
+        mEncapType = in.readInt();
+        mEncapSocketResourceId = in.readInt();
+        mEncapRemotePort = in.readInt();
+        mNattKeepaliveInterval = in.readInt();
+        mMarkValue = in.readInt();
+        mMarkMask = in.readInt();
+        mXfrmInterfaceId = in.readInt();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder strBuilder = new StringBuilder();
+        strBuilder
+                .append("{mMode=")
+                .append(mMode == IpSecTransform.MODE_TUNNEL ? "TUNNEL" : "TRANSPORT")
+                .append(", mSourceAddress=")
+                .append(mSourceAddress)
+                .append(", mDestinationAddress=")
+                .append(mDestinationAddress)
+                .append(", mNetwork=")
+                .append(mNetwork)
+                .append(", mEncapType=")
+                .append(mEncapType)
+                .append(", mEncapSocketResourceId=")
+                .append(mEncapSocketResourceId)
+                .append(", mEncapRemotePort=")
+                .append(mEncapRemotePort)
+                .append(", mNattKeepaliveInterval=")
+                .append(mNattKeepaliveInterval)
+                .append("{mSpiResourceId=")
+                .append(mSpiResourceId)
+                .append(", mEncryption=")
+                .append(mEncryption)
+                .append(", mAuthentication=")
+                .append(mAuthentication)
+                .append(", mAuthenticatedEncryption=")
+                .append(mAuthenticatedEncryption)
+                .append(", mMarkValue=")
+                .append(mMarkValue)
+                .append(", mMarkMask=")
+                .append(mMarkMask)
+                .append(", mXfrmInterfaceId=")
+                .append(mXfrmInterfaceId)
+                .append("}");
+
+        return strBuilder.toString();
+    }
+
+    public static final @android.annotation.NonNull Parcelable.Creator<IpSecConfig> CREATOR =
+            new Parcelable.Creator<IpSecConfig>() {
+                public IpSecConfig createFromParcel(Parcel in) {
+                    return new IpSecConfig(in);
+                }
+
+                public IpSecConfig[] newArray(int size) {
+                    return new IpSecConfig[size];
+                }
+            };
+
+    @Override
+    public boolean equals(@Nullable Object other) {
+        if (!(other instanceof IpSecConfig)) return false;
+        final IpSecConfig rhs = (IpSecConfig) other;
+        return (mMode == rhs.mMode
+                && mSourceAddress.equals(rhs.mSourceAddress)
+                && mDestinationAddress.equals(rhs.mDestinationAddress)
+                && ((mNetwork != null && mNetwork.equals(rhs.mNetwork))
+                        || (mNetwork == rhs.mNetwork))
+                && mEncapType == rhs.mEncapType
+                && mEncapSocketResourceId == rhs.mEncapSocketResourceId
+                && mEncapRemotePort == rhs.mEncapRemotePort
+                && mNattKeepaliveInterval == rhs.mNattKeepaliveInterval
+                && mSpiResourceId == rhs.mSpiResourceId
+                && IpSecAlgorithm.equals(mEncryption, rhs.mEncryption)
+                && IpSecAlgorithm.equals(mAuthenticatedEncryption, rhs.mAuthenticatedEncryption)
+                && IpSecAlgorithm.equals(mAuthentication, rhs.mAuthentication)
+                && mMarkValue == rhs.mMarkValue
+                && mMarkMask == rhs.mMarkMask
+                && mXfrmInterfaceId == rhs.mXfrmInterfaceId);
+    }
+}
diff --git a/framework-t/src/android/net/IpSecManager.java b/framework-t/src/android/net/IpSecManager.java
new file mode 100644
index 0000000..9cb0947
--- /dev/null
+++ b/framework-t/src/android/net/IpSecManager.java
@@ -0,0 +1,1065 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.RequiresFeature;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
+import android.annotation.SystemService;
+import android.annotation.TestApi;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Binder;
+import android.os.IBinder;
+import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.system.ErrnoException;
+import android.system.OsConstants;
+import android.util.AndroidException;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import dalvik.system.CloseGuard;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.util.Objects;
+
+/**
+ * This class contains methods for managing IPsec sessions. Once configured, the kernel will apply
+ * confidentiality (encryption) and integrity (authentication) to IP traffic.
+ *
+ * <p>Note that not all aspects of IPsec are permitted by this API. Applications may create
+ * transport mode security associations and apply them to individual sockets. Applications looking
+ * to create an IPsec VPN should use {@link VpnManager} and {@link Ikev2VpnProfile}.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4301">RFC 4301, Security Architecture for the
+ *     Internet Protocol</a>
+ */
+@SystemService(Context.IPSEC_SERVICE)
+public class IpSecManager {
+    private static final String TAG = "IpSecManager";
+
+    /**
+     * Used when applying a transform to direct traffic through an {@link IpSecTransform}
+     * towards the host.
+     *
+     * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}.
+     */
+    public static final int DIRECTION_IN = 0;
+
+    /**
+     * Used when applying a transform to direct traffic through an {@link IpSecTransform}
+     * away from the host.
+     *
+     * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}.
+     */
+    public static final int DIRECTION_OUT = 1;
+
+    /**
+     * Used when applying a transform to direct traffic through an {@link IpSecTransform} for
+     * forwarding between interfaces.
+     *
+     * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static final int DIRECTION_FWD = 2;
+
+    /** @hide */
+    @IntDef(value = {DIRECTION_IN, DIRECTION_OUT})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface PolicyDirection {}
+
+    /**
+     * The Security Parameter Index (SPI) 0 indicates an unknown or invalid index.
+     *
+     * <p>No IPsec packet may contain an SPI of 0.
+     *
+     * @hide
+     */
+    @TestApi public static final int INVALID_SECURITY_PARAMETER_INDEX = 0;
+
+    /** @hide */
+    public interface Status {
+        int OK = 0;
+        int RESOURCE_UNAVAILABLE = 1;
+        int SPI_UNAVAILABLE = 2;
+    }
+
+    /** @hide */
+    public static final int INVALID_RESOURCE_ID = -1;
+
+    /**
+     * Thrown to indicate that a requested SPI is in use.
+     *
+     * <p>The combination of remote {@code InetAddress} and SPI must be unique across all apps on
+     * one device. If this error is encountered, a new SPI is required before a transform may be
+     * created. This error can be avoided by calling {@link
+     * IpSecManager#allocateSecurityParameterIndex}.
+     */
+    public static final class SpiUnavailableException extends AndroidException {
+        private final int mSpi;
+
+        /**
+         * Construct an exception indicating that a transform with the given SPI is already in use
+         * or otherwise unavailable.
+         *
+         * @param msg description indicating the colliding SPI
+         * @param spi the SPI that could not be used due to a collision
+         */
+        SpiUnavailableException(String msg, int spi) {
+            super(msg + " (spi: " + spi + ")");
+            mSpi = spi;
+        }
+
+        /** Get the SPI that caused a collision. */
+        public int getSpi() {
+            return mSpi;
+        }
+    }
+
+    /**
+     * Thrown to indicate that an IPsec resource is unavailable.
+     *
+     * <p>This could apply to resources such as sockets, {@link SecurityParameterIndex}, {@link
+     * IpSecTransform}, or other system resources. If this exception is thrown, users should release
+     * allocated objects of the type requested.
+     */
+    public static final class ResourceUnavailableException extends AndroidException {
+
+        ResourceUnavailableException(String msg) {
+            super(msg);
+        }
+    }
+
+    private final Context mContext;
+    private final IIpSecService mService;
+
+    /**
+     * This class represents a reserved SPI.
+     *
+     * <p>Objects of this type are used to track reserved security parameter indices. They can be
+     * obtained by calling {@link IpSecManager#allocateSecurityParameterIndex} and must be released
+     * by calling {@link #close()} when they are no longer needed.
+     */
+    public static final class SecurityParameterIndex implements AutoCloseable {
+        private final IIpSecService mService;
+        private final InetAddress mDestinationAddress;
+        private final CloseGuard mCloseGuard = CloseGuard.get();
+        private int mSpi = INVALID_SECURITY_PARAMETER_INDEX;
+        private int mResourceId = INVALID_RESOURCE_ID;
+
+        /** Get the underlying SPI held by this object. */
+        public int getSpi() {
+            return mSpi;
+        }
+
+        /**
+         * Release an SPI that was previously reserved.
+         *
+         * <p>Release an SPI for use by other users in the system. If a SecurityParameterIndex is
+         * applied to an IpSecTransform, it will become unusable for future transforms but should
+         * still be closed to ensure system resources are released.
+         */
+        @Override
+        public void close() {
+            try {
+                mService.releaseSecurityParameterIndex(mResourceId);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            } catch (Exception e) {
+                // On close we swallow all random exceptions since failure to close is not
+                // actionable by the user.
+                Log.e(TAG, "Failed to close " + this + ", Exception=" + e);
+            } finally {
+                mResourceId = INVALID_RESOURCE_ID;
+                mCloseGuard.close();
+            }
+        }
+
+        /** Check that the SPI was closed properly. */
+        @Override
+        protected void finalize() throws Throwable {
+            if (mCloseGuard != null) {
+                mCloseGuard.warnIfOpen();
+            }
+
+            close();
+        }
+
+        private SecurityParameterIndex(
+                @NonNull IIpSecService service, InetAddress destinationAddress, int spi)
+                throws ResourceUnavailableException, SpiUnavailableException {
+            mService = service;
+            mDestinationAddress = destinationAddress;
+            try {
+                IpSecSpiResponse result =
+                        mService.allocateSecurityParameterIndex(
+                                destinationAddress.getHostAddress(), spi, new Binder());
+
+                if (result == null) {
+                    throw new NullPointerException("Received null response from IpSecService");
+                }
+
+                int status = result.status;
+                switch (status) {
+                    case Status.OK:
+                        break;
+                    case Status.RESOURCE_UNAVAILABLE:
+                        throw new ResourceUnavailableException(
+                                "No more SPIs may be allocated by this requester.");
+                    case Status.SPI_UNAVAILABLE:
+                        throw new SpiUnavailableException("Requested SPI is unavailable", spi);
+                    default:
+                        throw new RuntimeException(
+                                "Unknown status returned by IpSecService: " + status);
+                }
+                mSpi = result.spi;
+                mResourceId = result.resourceId;
+
+                if (mSpi == INVALID_SECURITY_PARAMETER_INDEX) {
+                    throw new RuntimeException("Invalid SPI returned by IpSecService: " + status);
+                }
+
+                if (mResourceId == INVALID_RESOURCE_ID) {
+                    throw new RuntimeException(
+                            "Invalid Resource ID returned by IpSecService: " + status);
+                }
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            mCloseGuard.open("open");
+        }
+
+        /** @hide */
+        @VisibleForTesting
+        public int getResourceId() {
+            return mResourceId;
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                .append("SecurityParameterIndex{spi=")
+                .append(mSpi)
+                .append(",resourceId=")
+                .append(mResourceId)
+                .append("}")
+                .toString();
+        }
+    }
+
+    /**
+     * Reserve a random SPI for traffic bound to or from the specified destination address.
+     *
+     * <p>If successful, this SPI is guaranteed available until released by a call to {@link
+     * SecurityParameterIndex#close()}.
+     *
+     * @param destinationAddress the destination address for traffic bearing the requested SPI.
+     *     For inbound traffic, the destination should be an address currently assigned on-device.
+     * @return the reserved SecurityParameterIndex
+     * @throws ResourceUnavailableException indicating that too many SPIs are
+     *     currently allocated for this user
+     */
+    @NonNull
+    public SecurityParameterIndex allocateSecurityParameterIndex(
+                @NonNull InetAddress destinationAddress) throws ResourceUnavailableException {
+        try {
+            return new SecurityParameterIndex(
+                    mService,
+                    destinationAddress,
+                    IpSecManager.INVALID_SECURITY_PARAMETER_INDEX);
+        } catch (ServiceSpecificException e) {
+            throw rethrowUncheckedExceptionFromServiceSpecificException(e);
+        } catch (SpiUnavailableException unlikely) {
+            // Because this function allocates a totally random SPI, it really shouldn't ever
+            // fail to allocate an SPI; we simply need this because the exception is checked.
+            throw new ResourceUnavailableException("No SPIs available");
+        }
+    }
+
+    /**
+     * Reserve the requested SPI for traffic bound to or from the specified destination address.
+     *
+     * <p>If successful, this SPI is guaranteed available until released by a call to {@link
+     * SecurityParameterIndex#close()}.
+     *
+     * @param destinationAddress the destination address for traffic bearing the requested SPI.
+     *     For inbound traffic, the destination should be an address currently assigned on-device.
+     * @param requestedSpi the requested SPI. The range 1-255 is reserved and may not be used. See
+     *     RFC 4303 Section 2.1.
+     * @return the reserved SecurityParameterIndex
+     * @throws ResourceUnavailableException indicating that too many SPIs are
+     *     currently allocated for this user
+     * @throws SpiUnavailableException indicating that the requested SPI could not be
+     *     reserved
+     */
+    @NonNull
+    public SecurityParameterIndex allocateSecurityParameterIndex(
+            @NonNull InetAddress destinationAddress, int requestedSpi)
+            throws SpiUnavailableException, ResourceUnavailableException {
+        if (requestedSpi == IpSecManager.INVALID_SECURITY_PARAMETER_INDEX) {
+            throw new IllegalArgumentException("Requested SPI must be a valid (non-zero) SPI");
+        }
+        try {
+            return new SecurityParameterIndex(mService, destinationAddress, requestedSpi);
+        } catch (ServiceSpecificException e) {
+            throw rethrowUncheckedExceptionFromServiceSpecificException(e);
+        }
+    }
+
+    /**
+     * Apply an IPsec transform to a stream socket.
+     *
+     * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the
+     * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When
+     * the transform is removed from the socket by calling {@link #removeTransportModeTransforms},
+     * unprotected traffic can resume on that socket.
+     *
+     * <p>For security reasons, the destination address of any traffic on the socket must match the
+     * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any
+     * other IP address will result in an IOException. In addition, reads and writes on the socket
+     * will throw IOException if the user deactivates the transform (by calling {@link
+     * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}.
+     *
+     * <p>Note that when applied to TCP sockets, calling {@link IpSecTransform#close()} on an
+     * applied transform before completion of graceful shutdown may result in the shutdown sequence
+     * failing to complete. As such, applications requiring graceful shutdown MUST close the socket
+     * prior to deactivating the applied transform. Socket closure may be performed asynchronously
+     * (in batches), so the returning of a close function does not guarantee shutdown of a socket.
+     * Setting an SO_LINGER timeout results in socket closure being performed synchronously, and is
+     * sufficient to ensure shutdown.
+     *
+     * Specifically, if the transform is deactivated (by calling {@link IpSecTransform#close()}),
+     * prior to the socket being closed, the standard [FIN - FIN/ACK - ACK], or the reset [RST]
+     * packets are dropped due to the lack of a valid Transform. Similarly, if a socket without the
+     * SO_LINGER option set is closed, the delayed/batched FIN packets may be dropped.
+     *
+     * <h4>Rekey Procedure</h4>
+     *
+     * <p>When applying a new tranform to a socket in the outbound direction, the previous transform
+     * will be removed and the new transform will take effect immediately, sending all traffic on
+     * the new transform; however, when applying a transform in the inbound direction, traffic
+     * on the old transform will continue to be decrypted and delivered until that transform is
+     * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey
+     * procedures where both transforms are valid until both endpoints are using the new transform
+     * and all in-flight packets have been received.
+     *
+     * @param socket a stream socket
+     * @param direction the direction in which the transform should be applied
+     * @param transform a transport mode {@code IpSecTransform}
+     * @throws IOException indicating that the transform could not be applied
+     */
+    public void applyTransportModeTransform(@NonNull Socket socket,
+            @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException {
+        // Ensure creation of FD. See b/77548890 for more details.
+        socket.getSoLinger();
+
+        applyTransportModeTransform(socket.getFileDescriptor$(), direction, transform);
+    }
+
+    /**
+     * Apply an IPsec transform to a datagram socket.
+     *
+     * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the
+     * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When
+     * the transform is removed from the socket by calling {@link #removeTransportModeTransforms},
+     * unprotected traffic can resume on that socket.
+     *
+     * <p>For security reasons, the destination address of any traffic on the socket must match the
+     * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any
+     * other IP address will result in an IOException. In addition, reads and writes on the socket
+     * will throw IOException if the user deactivates the transform (by calling {@link
+     * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}.
+     *
+     * <h4>Rekey Procedure</h4>
+     *
+     * <p>When applying a new tranform to a socket in the outbound direction, the previous transform
+     * will be removed and the new transform will take effect immediately, sending all traffic on
+     * the new transform; however, when applying a transform in the inbound direction, traffic
+     * on the old transform will continue to be decrypted and delivered until that transform is
+     * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey
+     * procedures where both transforms are valid until both endpoints are using the new transform
+     * and all in-flight packets have been received.
+     *
+     * @param socket a datagram socket
+     * @param direction the direction in which the transform should be applied
+     * @param transform a transport mode {@code IpSecTransform}
+     * @throws IOException indicating that the transform could not be applied
+     */
+    public void applyTransportModeTransform(@NonNull DatagramSocket socket,
+            @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException {
+        applyTransportModeTransform(socket.getFileDescriptor$(), direction, transform);
+    }
+
+    /**
+     * Apply an IPsec transform to a socket.
+     *
+     * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the
+     * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When
+     * the transform is removed from the socket by calling {@link #removeTransportModeTransforms},
+     * unprotected traffic can resume on that socket.
+     *
+     * <p>For security reasons, the destination address of any traffic on the socket must match the
+     * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any
+     * other IP address will result in an IOException. In addition, reads and writes on the socket
+     * will throw IOException if the user deactivates the transform (by calling {@link
+     * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}.
+     *
+     * <p>Note that when applied to TCP sockets, calling {@link IpSecTransform#close()} on an
+     * applied transform before completion of graceful shutdown may result in the shutdown sequence
+     * failing to complete. As such, applications requiring graceful shutdown MUST close the socket
+     * prior to deactivating the applied transform. Socket closure may be performed asynchronously
+     * (in batches), so the returning of a close function does not guarantee shutdown of a socket.
+     * Setting an SO_LINGER timeout results in socket closure being performed synchronously, and is
+     * sufficient to ensure shutdown.
+     *
+     * Specifically, if the transform is deactivated (by calling {@link IpSecTransform#close()}),
+     * prior to the socket being closed, the standard [FIN - FIN/ACK - ACK], or the reset [RST]
+     * packets are dropped due to the lack of a valid Transform. Similarly, if a socket without the
+     * SO_LINGER option set is closed, the delayed/batched FIN packets may be dropped.
+     *
+     * <h4>Rekey Procedure</h4>
+     *
+     * <p>When applying a new tranform to a socket in the outbound direction, the previous transform
+     * will be removed and the new transform will take effect immediately, sending all traffic on
+     * the new transform; however, when applying a transform in the inbound direction, traffic
+     * on the old transform will continue to be decrypted and delivered until that transform is
+     * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey
+     * procedures where both transforms are valid until both endpoints are using the new transform
+     * and all in-flight packets have been received.
+     *
+     * @param socket a socket file descriptor
+     * @param direction the direction in which the transform should be applied
+     * @param transform a transport mode {@code IpSecTransform}
+     * @throws IOException indicating that the transform could not be applied
+     */
+    public void applyTransportModeTransform(@NonNull FileDescriptor socket,
+            @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException {
+        // We dup() the FileDescriptor here because if we don't, then the ParcelFileDescriptor()
+        // constructor takes control and closes the user's FD when we exit the method.
+        try (ParcelFileDescriptor pfd = ParcelFileDescriptor.dup(socket)) {
+            mService.applyTransportModeTransform(pfd, direction, transform.getResourceId());
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Remove an IPsec transform from a stream socket.
+     *
+     * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a
+     * socket allows the socket to be reused for communication in the clear.
+     *
+     * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling
+     * {@link IpSecTransform#close()}, then communication on the socket will fail until this method
+     * is called.
+     *
+     * @param socket a socket that previously had a transform applied to it
+     * @throws IOException indicating that the transform could not be removed from the socket
+     */
+    public void removeTransportModeTransforms(@NonNull Socket socket) throws IOException {
+        // Ensure creation of FD. See b/77548890 for more details.
+        socket.getSoLinger();
+
+        removeTransportModeTransforms(socket.getFileDescriptor$());
+    }
+
+    /**
+     * Remove an IPsec transform from a datagram socket.
+     *
+     * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a
+     * socket allows the socket to be reused for communication in the clear.
+     *
+     * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling
+     * {@link IpSecTransform#close()}, then communication on the socket will fail until this method
+     * is called.
+     *
+     * @param socket a socket that previously had a transform applied to it
+     * @throws IOException indicating that the transform could not be removed from the socket
+     */
+    public void removeTransportModeTransforms(@NonNull DatagramSocket socket) throws IOException {
+        removeTransportModeTransforms(socket.getFileDescriptor$());
+    }
+
+    /**
+     * Remove an IPsec transform from a socket.
+     *
+     * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a
+     * socket allows the socket to be reused for communication in the clear.
+     *
+     * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling
+     * {@link IpSecTransform#close()}, then communication on the socket will fail until this method
+     * is called.
+     *
+     * @param socket a socket that previously had a transform applied to it
+     * @throws IOException indicating that the transform could not be removed from the socket
+     */
+    public void removeTransportModeTransforms(@NonNull FileDescriptor socket) throws IOException {
+        try (ParcelFileDescriptor pfd = ParcelFileDescriptor.dup(socket)) {
+            mService.removeTransportModeTransforms(pfd);
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Remove a Tunnel Mode IPsec Transform from a {@link Network}. This must be used as part of
+     * cleanup if a tunneled Network experiences a change in default route. The Network will drop
+     * all traffic that cannot be routed to the Tunnel's outbound interface. If that interface is
+     * lost, all traffic will drop.
+     *
+     * <p>TODO: Update javadoc for tunnel mode APIs at the same time the APIs are re-worked.
+     *
+     * @param net a network that currently has transform applied to it.
+     * @param transform a Tunnel Mode IPsec Transform that has been previously applied to the given
+     *     network
+     * @hide
+     */
+    public void removeTunnelModeTransform(Network net, IpSecTransform transform) {}
+
+    /**
+     * This class provides access to a UDP encapsulation Socket.
+     *
+     * <p>{@code UdpEncapsulationSocket} wraps a system-provided datagram socket intended for IKEv2
+     * signalling and UDP encapsulated IPsec traffic. Instances can be obtained by calling {@link
+     * IpSecManager#openUdpEncapsulationSocket}. The provided socket cannot be re-bound by the
+     * caller. The caller should not close the {@code FileDescriptor} returned by {@link
+     * #getFileDescriptor}, but should use {@link #close} instead.
+     *
+     * <p>Allowing the user to close or unbind a UDP encapsulation socket could impact the traffic
+     * of the next user who binds to that port. To prevent this scenario, these sockets are held
+     * open by the system so that they may only be closed by calling {@link #close} or when the user
+     * process exits.
+     */
+    public static final class UdpEncapsulationSocket implements AutoCloseable {
+        private final ParcelFileDescriptor mPfd;
+        private final IIpSecService mService;
+        private int mResourceId = INVALID_RESOURCE_ID;
+        private final int mPort;
+        private final CloseGuard mCloseGuard = CloseGuard.get();
+
+        private UdpEncapsulationSocket(@NonNull IIpSecService service, int port)
+                throws ResourceUnavailableException, IOException {
+            mService = service;
+            try {
+                IpSecUdpEncapResponse result =
+                        mService.openUdpEncapsulationSocket(port, new Binder());
+                switch (result.status) {
+                    case Status.OK:
+                        break;
+                    case Status.RESOURCE_UNAVAILABLE:
+                        throw new ResourceUnavailableException(
+                                "No more Sockets may be allocated by this requester.");
+                    default:
+                        throw new RuntimeException(
+                                "Unknown status returned by IpSecService: " + result.status);
+                }
+                mResourceId = result.resourceId;
+                mPort = result.port;
+                mPfd = result.fileDescriptor;
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            mCloseGuard.open("constructor");
+        }
+
+        /** Get the encapsulation socket's file descriptor. */
+        public FileDescriptor getFileDescriptor() {
+            if (mPfd == null) {
+                return null;
+            }
+            return mPfd.getFileDescriptor();
+        }
+
+        /** Get the bound port of the wrapped socket. */
+        public int getPort() {
+            return mPort;
+        }
+
+        /**
+         * Close this socket.
+         *
+         * <p>This closes the wrapped socket. Open encapsulation sockets count against a user's
+         * resource limits, and forgetting to close them eventually will result in {@link
+         * ResourceUnavailableException} being thrown.
+         */
+        @Override
+        public void close() throws IOException {
+            try {
+                mService.closeUdpEncapsulationSocket(mResourceId);
+                mResourceId = INVALID_RESOURCE_ID;
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            } catch (Exception e) {
+                // On close we swallow all random exceptions since failure to close is not
+                // actionable by the user.
+                Log.e(TAG, "Failed to close " + this + ", Exception=" + e);
+            } finally {
+                mResourceId = INVALID_RESOURCE_ID;
+                mCloseGuard.close();
+            }
+
+            try {
+                mPfd.close();
+            } catch (IOException e) {
+                Log.e(TAG, "Failed to close UDP Encapsulation Socket with Port= " + mPort);
+                throw e;
+            }
+        }
+
+        /** Check that the socket was closed properly. */
+        @Override
+        protected void finalize() throws Throwable {
+            if (mCloseGuard != null) {
+                mCloseGuard.warnIfOpen();
+            }
+            close();
+        }
+
+        /** @hide */
+        @SystemApi(client = MODULE_LIBRARIES)
+        public int getResourceId() {
+            return mResourceId;
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                .append("UdpEncapsulationSocket{port=")
+                .append(mPort)
+                .append(",resourceId=")
+                .append(mResourceId)
+                .append("}")
+                .toString();
+        }
+    };
+
+    /**
+     * Open a socket for UDP encapsulation and bind to the given port.
+     *
+     * <p>See {@link UdpEncapsulationSocket} for the proper way to close the returned socket.
+     *
+     * @param port a local UDP port
+     * @return a socket that is bound to the given port
+     * @throws IOException indicating that the socket could not be opened or bound
+     * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open
+     */
+    // Returning a socket in this fashion that has been created and bound by the system
+    // is the only safe way to ensure that a socket is both accessible to the user and
+    // safely usable for Encapsulation without allowing a user to possibly unbind from/close
+    // the port, which could potentially impact the traffic of the next user who binds to that
+    // socket.
+    @NonNull
+    public UdpEncapsulationSocket openUdpEncapsulationSocket(int port)
+            throws IOException, ResourceUnavailableException {
+        /*
+         * Most range checking is done in the service, but this version of the constructor expects
+         * a valid port number, and zero cannot be checked after being passed to the service.
+         */
+        if (port == 0) {
+            throw new IllegalArgumentException("Specified port must be a valid port number!");
+        }
+        try {
+            return new UdpEncapsulationSocket(mService, port);
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        }
+    }
+
+    /**
+     * Open a socket for UDP encapsulation.
+     *
+     * <p>See {@link UdpEncapsulationSocket} for the proper way to close the returned socket.
+     *
+     * <p>The local port of the returned socket can be obtained by calling {@link
+     * UdpEncapsulationSocket#getPort()}.
+     *
+     * @return a socket that is bound to a local port
+     * @throws IOException indicating that the socket could not be opened or bound
+     * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open
+     */
+    // Returning a socket in this fashion that has been created and bound by the system
+    // is the only safe way to ensure that a socket is both accessible to the user and
+    // safely usable for Encapsulation without allowing a user to possibly unbind from/close
+    // the port, which could potentially impact the traffic of the next user who binds to that
+    // socket.
+    @NonNull
+    public UdpEncapsulationSocket openUdpEncapsulationSocket()
+            throws IOException, ResourceUnavailableException {
+        try {
+            return new UdpEncapsulationSocket(mService, 0);
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        }
+    }
+
+    /**
+     * This class represents an IpSecTunnelInterface
+     *
+     * <p>IpSecTunnelInterface objects track tunnel interfaces that serve as
+     * local endpoints for IPsec tunnels.
+     *
+     * <p>Creating an IpSecTunnelInterface creates a device to which IpSecTransforms may be
+     * applied to provide IPsec security to packets sent through the tunnel. While a tunnel
+     * cannot be used in standalone mode within Android, the higher layers may use the tunnel
+     * to create Network objects which are accessible to the Android system.
+     * @hide
+     */
+    @SystemApi
+    public static final class IpSecTunnelInterface implements AutoCloseable {
+        private final String mOpPackageName;
+        private final IIpSecService mService;
+        private final InetAddress mRemoteAddress;
+        private final InetAddress mLocalAddress;
+        private final Network mUnderlyingNetwork;
+        private final CloseGuard mCloseGuard = CloseGuard.get();
+        private String mInterfaceName;
+        private int mResourceId = INVALID_RESOURCE_ID;
+
+        /** Get the underlying SPI held by this object. */
+        @NonNull
+        public String getInterfaceName() {
+            return mInterfaceName;
+        }
+
+        /**
+         * Add an address to the IpSecTunnelInterface
+         *
+         * <p>Add an address which may be used as the local inner address for
+         * tunneled traffic.
+         *
+         * @param address the local address for traffic inside the tunnel
+         * @param prefixLen length of the InetAddress prefix
+         * @hide
+         */
+        @SystemApi
+        @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+        @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+        public void addAddress(@NonNull InetAddress address, int prefixLen) throws IOException {
+            try {
+                mService.addAddressToTunnelInterface(
+                        mResourceId, new LinkAddress(address, prefixLen), mOpPackageName);
+            } catch (ServiceSpecificException e) {
+                throw rethrowCheckedExceptionFromServiceSpecificException(e);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+        }
+
+        /**
+         * Remove an address from the IpSecTunnelInterface
+         *
+         * <p>Remove an address which was previously added to the IpSecTunnelInterface
+         *
+         * @param address to be removed
+         * @param prefixLen length of the InetAddress prefix
+         * @hide
+         */
+        @SystemApi
+        @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+        @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+        public void removeAddress(@NonNull InetAddress address, int prefixLen) throws IOException {
+            try {
+                mService.removeAddressFromTunnelInterface(
+                        mResourceId, new LinkAddress(address, prefixLen), mOpPackageName);
+            } catch (ServiceSpecificException e) {
+                throw rethrowCheckedExceptionFromServiceSpecificException(e);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+        }
+
+        /**
+         * Update the underlying network for this IpSecTunnelInterface.
+         *
+         * <p>This new underlying network will be used for all transforms applied AFTER this call is
+         * complete. Before new {@link IpSecTransform}(s) with matching addresses are applied to
+         * this tunnel interface, traffic will still use the old SA, and be routed on the old
+         * underlying network.
+         *
+         * <p>To migrate IPsec tunnel mode traffic, a caller should:
+         *
+         * <ol>
+         *   <li>Update the IpSecTunnelInterface’s underlying network.
+         *   <li>Apply {@link IpSecTransform}(s) with matching addresses to this
+         *       IpSecTunnelInterface.
+         * </ol>
+         *
+         * @param underlyingNetwork the new {@link Network} that will carry traffic for this tunnel.
+         *     This network MUST never be the network exposing this IpSecTunnelInterface, otherwise
+         *     this method will throw an {@link IllegalArgumentException}. If the
+         *     IpSecTunnelInterface is later added to this network, all outbound traffic will be
+         *     blackholed.
+         */
+        // TODO: b/169171001 Update the documentation when transform migration is supported.
+        // The purpose of making updating network and applying transforms separate is to leave open
+        // the possibility to support lossless migration procedures. To do that, Android platform
+        // will need to support multiple inbound tunnel mode transforms, just like it can support
+        // multiple transport mode transforms.
+        @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+        @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+        public void setUnderlyingNetwork(@NonNull Network underlyingNetwork) throws IOException {
+            try {
+                mService.setNetworkForTunnelInterface(
+                        mResourceId, underlyingNetwork, mOpPackageName);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+        }
+
+        private IpSecTunnelInterface(@NonNull Context ctx, @NonNull IIpSecService service,
+                @NonNull InetAddress localAddress, @NonNull InetAddress remoteAddress,
+                @NonNull Network underlyingNetwork)
+                throws ResourceUnavailableException, IOException {
+            mOpPackageName = ctx.getOpPackageName();
+            mService = service;
+            mLocalAddress = localAddress;
+            mRemoteAddress = remoteAddress;
+            mUnderlyingNetwork = underlyingNetwork;
+
+            try {
+                IpSecTunnelInterfaceResponse result =
+                        mService.createTunnelInterface(
+                                localAddress.getHostAddress(),
+                                remoteAddress.getHostAddress(),
+                                underlyingNetwork,
+                                new Binder(),
+                                mOpPackageName);
+                switch (result.status) {
+                    case Status.OK:
+                        break;
+                    case Status.RESOURCE_UNAVAILABLE:
+                        throw new ResourceUnavailableException(
+                                "No more tunnel interfaces may be allocated by this requester.");
+                    default:
+                        throw new RuntimeException(
+                                "Unknown status returned by IpSecService: " + result.status);
+                }
+                mResourceId = result.resourceId;
+                mInterfaceName = result.interfaceName;
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            mCloseGuard.open("constructor");
+        }
+
+        /**
+         * Delete an IpSecTunnelInterface
+         *
+         * <p>Calling close will deallocate the IpSecTunnelInterface and all of its system
+         * resources. Any packets bound for this interface either inbound or outbound will
+         * all be lost.
+         */
+        @Override
+        public void close() {
+            try {
+                mService.deleteTunnelInterface(mResourceId, mOpPackageName);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            } catch (Exception e) {
+                // On close we swallow all random exceptions since failure to close is not
+                // actionable by the user.
+                Log.e(TAG, "Failed to close " + this + ", Exception=" + e);
+            } finally {
+                mResourceId = INVALID_RESOURCE_ID;
+                mCloseGuard.close();
+            }
+        }
+
+        /** Check that the Interface was closed properly. */
+        @Override
+        protected void finalize() throws Throwable {
+            if (mCloseGuard != null) {
+                mCloseGuard.warnIfOpen();
+            }
+            close();
+        }
+
+        /** @hide */
+        @VisibleForTesting
+        public int getResourceId() {
+            return mResourceId;
+        }
+
+        @NonNull
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                .append("IpSecTunnelInterface{ifname=")
+                .append(mInterfaceName)
+                .append(",resourceId=")
+                .append(mResourceId)
+                .append("}")
+                .toString();
+        }
+    }
+
+    /**
+     * Create a new IpSecTunnelInterface as a local endpoint for tunneled IPsec traffic.
+     *
+     * <p>An application that creates tunnels is responsible for cleaning up the tunnel when the
+     * underlying network goes away, and the onLost() callback is received.
+     *
+     * @param localAddress The local addres of the tunnel
+     * @param remoteAddress The local addres of the tunnel
+     * @param underlyingNetwork the {@link Network} that will carry traffic for this tunnel.
+     *        This network should almost certainly be a network such as WiFi with an L2 address.
+     * @return a new {@link IpSecManager#IpSecTunnelInterface} with the specified properties
+     * @throws IOException indicating that the socket could not be opened or bound
+     * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open
+     * @hide
+     */
+    @SystemApi
+    @NonNull
+    @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+    @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+    public IpSecTunnelInterface createIpSecTunnelInterface(@NonNull InetAddress localAddress,
+            @NonNull InetAddress remoteAddress, @NonNull Network underlyingNetwork)
+            throws ResourceUnavailableException, IOException {
+        try {
+            return new IpSecTunnelInterface(
+                    mContext, mService, localAddress, remoteAddress, underlyingNetwork);
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        }
+    }
+
+    /**
+     * Apply an active Tunnel Mode IPsec Transform to a {@link IpSecTunnelInterface}, which will
+     * tunnel all traffic for the given direction through the underlying network's interface with
+     * IPsec (applies an outer IP header and IPsec Header to all traffic, and expects an additional
+     * IP header and IPsec Header on all inbound traffic).
+     * <p>Applications should probably not use this API directly.
+     *
+     *
+     * @param tunnel The {@link IpSecManager#IpSecTunnelInterface} that will use the supplied
+     *        transform.
+     * @param direction the direction, {@link DIRECTION_OUT} or {@link #DIRECTION_IN} in which
+     *        the transform will be used.
+     * @param transform an {@link IpSecTransform} created in tunnel mode
+     * @throws IOException indicating that the transform could not be applied due to a lower
+     *         layer failure.
+     * @hide
+     */
+    @SystemApi
+    @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+    @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+    public void applyTunnelModeTransform(@NonNull IpSecTunnelInterface tunnel,
+            @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException {
+        try {
+            mService.applyTunnelModeTransform(
+                    tunnel.getResourceId(), direction,
+                    transform.getResourceId(), mContext.getOpPackageName());
+        } catch (ServiceSpecificException e) {
+            throw rethrowCheckedExceptionFromServiceSpecificException(e);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * @hide
+     */
+    public IpSecTransformResponse createTransform(IpSecConfig config, IBinder binder,
+            String callingPackage) {
+        try {
+            return mService.createTransform(config, binder, callingPackage);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * @hide
+     */
+    public void deleteTransform(int resourceId) {
+        try {
+            mService.deleteTransform(resourceId);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Construct an instance of IpSecManager within an application context.
+     *
+     * @param context the application context for this manager
+     * @hide
+     */
+    public IpSecManager(Context ctx, IIpSecService service) {
+        mContext = ctx;
+        mService = Objects.requireNonNull(service, "missing service");
+    }
+
+    private static void maybeHandleServiceSpecificException(ServiceSpecificException sse) {
+        // OsConstants are late binding, so switch statements can't be used.
+        if (sse.errorCode == OsConstants.EINVAL) {
+            throw new IllegalArgumentException(sse);
+        } else if (sse.errorCode == OsConstants.EAGAIN) {
+            throw new IllegalStateException(sse);
+        } else if (sse.errorCode == OsConstants.EOPNOTSUPP
+                || sse.errorCode == OsConstants.EPROTONOSUPPORT) {
+            throw new UnsupportedOperationException(sse);
+        }
+    }
+
+    /**
+     * Convert an Errno SSE to the correct Unchecked exception type.
+     *
+     * This method never actually returns.
+     */
+    // package
+    static RuntimeException
+            rethrowUncheckedExceptionFromServiceSpecificException(ServiceSpecificException sse) {
+        maybeHandleServiceSpecificException(sse);
+        throw new RuntimeException(sse);
+    }
+
+    /**
+     * Convert an Errno SSE to the correct Checked or Unchecked exception type.
+     *
+     * This method may throw IOException, or it may throw an unchecked exception; it will never
+     * actually return.
+     */
+    // package
+    static IOException rethrowCheckedExceptionFromServiceSpecificException(
+            ServiceSpecificException sse) throws IOException {
+        // First see if this is an unchecked exception of a type we know.
+        // If so, then we prefer the unchecked (specific) type of exception.
+        maybeHandleServiceSpecificException(sse);
+        // If not, then all we can do is provide the SSE in the form of an IOException.
+        throw new ErrnoException(
+                "IpSec encountered errno=" + sse.errorCode, sse.errorCode).rethrowAsIOException();
+    }
+}
diff --git a/framework-t/src/android/net/IpSecSpiResponse.aidl b/framework-t/src/android/net/IpSecSpiResponse.aidl
new file mode 100644
index 0000000..6484a00
--- /dev/null
+++ b/framework-t/src/android/net/IpSecSpiResponse.aidl
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+parcelable IpSecSpiResponse;
diff --git a/framework-t/src/android/net/IpSecSpiResponse.java b/framework-t/src/android/net/IpSecSpiResponse.java
new file mode 100644
index 0000000..f99e570
--- /dev/null
+++ b/framework-t/src/android/net/IpSecSpiResponse.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * This class is used to return an SPI and corresponding status from the IpSecService to an
+ * IpSecManager.SecurityParameterIndex.
+ *
+ * @hide
+ */
+public final class IpSecSpiResponse implements Parcelable {
+    private static final String TAG = "IpSecSpiResponse";
+
+    public final int resourceId;
+    public final int status;
+    public final int spi;
+    // Parcelable Methods
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(status);
+        out.writeInt(resourceId);
+        out.writeInt(spi);
+    }
+
+    public IpSecSpiResponse(int inStatus, int inResourceId, int inSpi) {
+        status = inStatus;
+        resourceId = inResourceId;
+        spi = inSpi;
+    }
+
+    public IpSecSpiResponse(int inStatus) {
+        if (inStatus == IpSecManager.Status.OK) {
+            throw new IllegalArgumentException("Valid status implies other args must be provided");
+        }
+        status = inStatus;
+        resourceId = IpSecManager.INVALID_RESOURCE_ID;
+        spi = IpSecManager.INVALID_SECURITY_PARAMETER_INDEX;
+    }
+
+    private IpSecSpiResponse(Parcel in) {
+        status = in.readInt();
+        resourceId = in.readInt();
+        spi = in.readInt();
+    }
+
+    public static final @android.annotation.NonNull Parcelable.Creator<IpSecSpiResponse> CREATOR =
+            new Parcelable.Creator<IpSecSpiResponse>() {
+                public IpSecSpiResponse createFromParcel(Parcel in) {
+                    return new IpSecSpiResponse(in);
+                }
+
+                public IpSecSpiResponse[] newArray(int size) {
+                    return new IpSecSpiResponse[size];
+                }
+            };
+}
diff --git a/framework-t/src/android/net/IpSecTransform.java b/framework-t/src/android/net/IpSecTransform.java
new file mode 100644
index 0000000..68ae5de
--- /dev/null
+++ b/framework-t/src/android/net/IpSecTransform.java
@@ -0,0 +1,405 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import static android.net.IpSecManager.INVALID_RESOURCE_ID;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresFeature;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Binder;
+import android.os.ServiceSpecificException;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import dalvik.system.CloseGuard;
+
+import java.io.IOException;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.net.InetAddress;
+import java.util.Objects;
+
+/**
+ * This class represents a transform, which roughly corresponds to an IPsec Security Association.
+ *
+ * <p>Transforms are created using {@link IpSecTransform.Builder}. Each {@code IpSecTransform}
+ * object encapsulates the properties and state of an IPsec security association. That includes,
+ * but is not limited to, algorithm choice, key material, and allocated system resources.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4301">RFC 4301, Security Architecture for the
+ *     Internet Protocol</a>
+ */
+public final class IpSecTransform implements AutoCloseable {
+    private static final String TAG = "IpSecTransform";
+
+    /** @hide */
+    public static final int MODE_TRANSPORT = 0;
+
+    /** @hide */
+    public static final int MODE_TUNNEL = 1;
+
+    /** @hide */
+    public static final int ENCAP_NONE = 0;
+
+    /**
+     * IPsec traffic will be encapsulated within UDP, but with 8 zero-value bytes between the UDP
+     * header and payload. This prevents traffic from being interpreted as ESP or IKEv2.
+     *
+     * @hide
+     */
+    public static final int ENCAP_ESPINUDP_NON_IKE = 1;
+
+    /**
+     * IPsec traffic will be encapsulated within UDP as per
+     * <a href="https://tools.ietf.org/html/rfc3948">RFC 3498</a>.
+     *
+     * @hide
+     */
+    public static final int ENCAP_ESPINUDP = 2;
+
+    /** @hide */
+    @IntDef(value = {ENCAP_NONE, ENCAP_ESPINUDP, ENCAP_ESPINUDP_NON_IKE})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface EncapType {}
+
+    /** @hide */
+    @VisibleForTesting
+    public IpSecTransform(Context context, IpSecConfig config) {
+        mContext = context;
+        mConfig = new IpSecConfig(config);
+        mResourceId = INVALID_RESOURCE_ID;
+    }
+
+    private IpSecManager getIpSecManager(Context context) {
+        return context.getSystemService(IpSecManager.class);
+    }
+    /**
+     * Checks the result status and throws an appropriate exception if the status is not Status.OK.
+     */
+    private void checkResultStatus(int status)
+            throws IOException, IpSecManager.ResourceUnavailableException,
+                    IpSecManager.SpiUnavailableException {
+        switch (status) {
+            case IpSecManager.Status.OK:
+                return;
+                // TODO: Pass Error string back from bundle so that errors can be more specific
+            case IpSecManager.Status.RESOURCE_UNAVAILABLE:
+                throw new IpSecManager.ResourceUnavailableException(
+                        "Failed to allocate a new IpSecTransform");
+            case IpSecManager.Status.SPI_UNAVAILABLE:
+                Log.wtf(TAG, "Attempting to use an SPI that was somehow not reserved");
+                // Fall through
+            default:
+                throw new IllegalStateException(
+                        "Failed to Create a Transform with status code " + status);
+        }
+    }
+
+    private IpSecTransform activate()
+            throws IOException, IpSecManager.ResourceUnavailableException,
+                    IpSecManager.SpiUnavailableException {
+        synchronized (this) {
+            try {
+                IpSecTransformResponse result = getIpSecManager(mContext).createTransform(
+                        mConfig, new Binder(), mContext.getOpPackageName());
+                int status = result.status;
+                checkResultStatus(status);
+                mResourceId = result.resourceId;
+                Log.d(TAG, "Added Transform with Id " + mResourceId);
+                mCloseGuard.open("build");
+            } catch (ServiceSpecificException e) {
+                throw IpSecManager.rethrowUncheckedExceptionFromServiceSpecificException(e);
+            }
+        }
+
+        return this;
+    }
+
+    /**
+     * Standard equals.
+     */
+    public boolean equals(@Nullable Object other) {
+        if (this == other) return true;
+        if (!(other instanceof IpSecTransform)) return false;
+        final IpSecTransform rhs = (IpSecTransform) other;
+        return getConfig().equals(rhs.getConfig()) && mResourceId == rhs.mResourceId;
+    }
+
+    /**
+     * Deactivate this {@code IpSecTransform} and free allocated resources.
+     *
+     * <p>Deactivating a transform while it is still applied to a socket will result in errors on
+     * that socket. Make sure to remove transforms by calling {@link
+     * IpSecManager#removeTransportModeTransforms}. Note, removing an {@code IpSecTransform} from a
+     * socket will not deactivate it (because one transform may be applied to multiple sockets).
+     *
+     * <p>It is safe to call this method on a transform that has already been deactivated.
+     */
+    public void close() {
+        Log.d(TAG, "Removing Transform with Id " + mResourceId);
+
+        // Always safe to attempt cleanup
+        if (mResourceId == INVALID_RESOURCE_ID) {
+            mCloseGuard.close();
+            return;
+        }
+        try {
+            getIpSecManager(mContext).deleteTransform(mResourceId);
+        } catch (Exception e) {
+            // On close we swallow all random exceptions since failure to close is not
+            // actionable by the user.
+            Log.e(TAG, "Failed to close " + this + ", Exception=" + e);
+        } finally {
+            mResourceId = INVALID_RESOURCE_ID;
+            mCloseGuard.close();
+        }
+    }
+
+    /** Check that the transform was closed properly. */
+    @Override
+    protected void finalize() throws Throwable {
+        if (mCloseGuard != null) {
+            mCloseGuard.warnIfOpen();
+        }
+        close();
+    }
+
+    /* Package */
+    IpSecConfig getConfig() {
+        return mConfig;
+    }
+
+    private final IpSecConfig mConfig;
+    private int mResourceId;
+    private final Context mContext;
+    private final CloseGuard mCloseGuard = CloseGuard.get();
+
+    /** @hide */
+    @VisibleForTesting
+    public int getResourceId() {
+        return mResourceId;
+    }
+
+    /**
+     * A callback class to provide status information regarding a NAT-T keepalive session
+     *
+     * <p>Use this callback to receive status information regarding a NAT-T keepalive session
+     * by registering it when calling {@link #startNattKeepalive}.
+     *
+     * @hide
+     */
+    public static class NattKeepaliveCallback {
+        /** The specified {@code Network} is not connected. */
+        public static final int ERROR_INVALID_NETWORK = 1;
+        /** The hardware does not support this request. */
+        public static final int ERROR_HARDWARE_UNSUPPORTED = 2;
+        /** The hardware returned an error. */
+        public static final int ERROR_HARDWARE_ERROR = 3;
+
+        /** The requested keepalive was successfully started. */
+        public void onStarted() {}
+        /** The keepalive was successfully stopped. */
+        public void onStopped() {}
+        /** An error occurred. */
+        public void onError(int error) {}
+    }
+
+    /** This class is used to build {@link IpSecTransform} objects. */
+    public static class Builder {
+        private Context mContext;
+        private IpSecConfig mConfig;
+
+        /**
+         * Set the encryption algorithm.
+         *
+         * <p>Encryption is mutually exclusive with authenticated encryption.
+         *
+         * @param algo {@link IpSecAlgorithm} specifying the encryption to be applied.
+         */
+        @NonNull
+        public IpSecTransform.Builder setEncryption(@NonNull IpSecAlgorithm algo) {
+            // TODO: throw IllegalArgumentException if algo is not an encryption algorithm.
+            Objects.requireNonNull(algo);
+            mConfig.setEncryption(algo);
+            return this;
+        }
+
+        /**
+         * Set the authentication (integrity) algorithm.
+         *
+         * <p>Authentication is mutually exclusive with authenticated encryption.
+         *
+         * @param algo {@link IpSecAlgorithm} specifying the authentication to be applied.
+         */
+        @NonNull
+        public IpSecTransform.Builder setAuthentication(@NonNull IpSecAlgorithm algo) {
+            // TODO: throw IllegalArgumentException if algo is not an authentication algorithm.
+            Objects.requireNonNull(algo);
+            mConfig.setAuthentication(algo);
+            return this;
+        }
+
+        /**
+         * Set the authenticated encryption algorithm.
+         *
+         * <p>The Authenticated Encryption (AE) class of algorithms are also known as
+         * Authenticated Encryption with Associated Data (AEAD) algorithms, or Combined mode
+         * algorithms (as referred to in
+         * <a href="https://tools.ietf.org/html/rfc4301">RFC 4301</a>).
+         *
+         * <p>Authenticated encryption is mutually exclusive with encryption and authentication.
+         *
+         * @param algo {@link IpSecAlgorithm} specifying the authenticated encryption algorithm to
+         *     be applied.
+         */
+        @NonNull
+        public IpSecTransform.Builder setAuthenticatedEncryption(@NonNull IpSecAlgorithm algo) {
+            Objects.requireNonNull(algo);
+            mConfig.setAuthenticatedEncryption(algo);
+            return this;
+        }
+
+        /**
+         * Add UDP encapsulation to an IPv4 transform.
+         *
+         * <p>This allows IPsec traffic to pass through a NAT.
+         *
+         * @see <a href="https://tools.ietf.org/html/rfc3948">RFC 3948, UDP Encapsulation of IPsec
+         *     ESP Packets</a>
+         * @see <a href="https://tools.ietf.org/html/rfc7296#section-2.23">RFC 7296 section 2.23,
+         *     NAT Traversal of IKEv2</a>
+         * @param localSocket a socket for sending and receiving encapsulated traffic
+         * @param remotePort the UDP port number of the remote host that will send and receive
+         *     encapsulated traffic. In the case of IKEv2, this should be port 4500.
+         */
+        @NonNull
+        public IpSecTransform.Builder setIpv4Encapsulation(
+                @NonNull IpSecManager.UdpEncapsulationSocket localSocket, int remotePort) {
+            Objects.requireNonNull(localSocket);
+            mConfig.setEncapType(ENCAP_ESPINUDP);
+            if (localSocket.getResourceId() == INVALID_RESOURCE_ID) {
+                throw new IllegalArgumentException("Invalid UdpEncapsulationSocket");
+            }
+            mConfig.setEncapSocketResourceId(localSocket.getResourceId());
+            mConfig.setEncapRemotePort(remotePort);
+            return this;
+        }
+
+        /**
+         * Build a transport mode {@link IpSecTransform}.
+         *
+         * <p>This builds and activates a transport mode transform. Note that an active transform
+         * will not affect any network traffic until it has been applied to one or more sockets.
+         *
+         * @see IpSecManager#applyTransportModeTransform
+         * @param sourceAddress the source {@code InetAddress} of traffic on sockets that will use
+         *     this transform; this address must belong to the Network used by all sockets that
+         *     utilize this transform; if provided, then only traffic originating from the
+         *     specified source address will be processed.
+         * @param spi a unique {@link IpSecManager.SecurityParameterIndex} to identify transformed
+         *     traffic
+         * @throws IllegalArgumentException indicating that a particular combination of transform
+         *     properties is invalid
+         * @throws IpSecManager.ResourceUnavailableException indicating that too many transforms
+         *     are active
+         * @throws IpSecManager.SpiUnavailableException indicating the rare case where an SPI
+         *     collides with an existing transform
+         * @throws IOException indicating other errors
+         */
+        @NonNull
+        public IpSecTransform buildTransportModeTransform(
+                @NonNull InetAddress sourceAddress,
+                @NonNull IpSecManager.SecurityParameterIndex spi)
+                throws IpSecManager.ResourceUnavailableException,
+                        IpSecManager.SpiUnavailableException, IOException {
+            Objects.requireNonNull(sourceAddress);
+            Objects.requireNonNull(spi);
+            if (spi.getResourceId() == INVALID_RESOURCE_ID) {
+                throw new IllegalArgumentException("Invalid SecurityParameterIndex");
+            }
+            mConfig.setMode(MODE_TRANSPORT);
+            mConfig.setSourceAddress(sourceAddress.getHostAddress());
+            mConfig.setSpiResourceId(spi.getResourceId());
+            // FIXME: modifying a builder after calling build can change the built transform.
+            return new IpSecTransform(mContext, mConfig).activate();
+        }
+
+        /**
+         * Build and return an {@link IpSecTransform} object as a Tunnel Mode Transform. Some
+         * parameters have interdependencies that are checked at build time.
+         *
+         * @param sourceAddress the {@link InetAddress} that provides the source address for this
+         *     IPsec tunnel. This is almost certainly an address belonging to the {@link Network}
+         *     that will originate the traffic, which is set as the {@link #setUnderlyingNetwork}.
+         * @param spi a unique {@link IpSecManager.SecurityParameterIndex} to identify transformed
+         *     traffic
+         * @throws IllegalArgumentException indicating that a particular combination of transform
+         *     properties is invalid.
+         * @throws IpSecManager.ResourceUnavailableException indicating that too many transforms
+         *     are active
+         * @throws IpSecManager.SpiUnavailableException indicating the rare case where an SPI
+         *     collides with an existing transform
+         * @throws IOException indicating other errors
+         * @hide
+         */
+        @SystemApi
+        @NonNull
+        @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS)
+        @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS)
+        public IpSecTransform buildTunnelModeTransform(
+                @NonNull InetAddress sourceAddress,
+                @NonNull IpSecManager.SecurityParameterIndex spi)
+                throws IpSecManager.ResourceUnavailableException,
+                        IpSecManager.SpiUnavailableException, IOException {
+            Objects.requireNonNull(sourceAddress);
+            Objects.requireNonNull(spi);
+            if (spi.getResourceId() == INVALID_RESOURCE_ID) {
+                throw new IllegalArgumentException("Invalid SecurityParameterIndex");
+            }
+            mConfig.setMode(MODE_TUNNEL);
+            mConfig.setSourceAddress(sourceAddress.getHostAddress());
+            mConfig.setSpiResourceId(spi.getResourceId());
+            return new IpSecTransform(mContext, mConfig).activate();
+        }
+
+        /**
+         * Create a new IpSecTransform.Builder.
+         *
+         * @param context current context
+         */
+        public Builder(@NonNull Context context) {
+            Objects.requireNonNull(context);
+            mContext = context;
+            mConfig = new IpSecConfig();
+        }
+    }
+
+    @Override
+    public String toString() {
+        return new StringBuilder()
+            .append("IpSecTransform{resourceId=")
+            .append(mResourceId)
+            .append("}")
+            .toString();
+    }
+}
diff --git a/framework-t/src/android/net/IpSecTransformResponse.aidl b/framework-t/src/android/net/IpSecTransformResponse.aidl
new file mode 100644
index 0000000..546230d
--- /dev/null
+++ b/framework-t/src/android/net/IpSecTransformResponse.aidl
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+parcelable IpSecTransformResponse;
diff --git a/framework-t/src/android/net/IpSecTransformResponse.java b/framework-t/src/android/net/IpSecTransformResponse.java
new file mode 100644
index 0000000..363f316
--- /dev/null
+++ b/framework-t/src/android/net/IpSecTransformResponse.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * This class is used to return an IpSecTransform resource Id and and corresponding status from the
+ * IpSecService to an IpSecTransform object.
+ *
+ * @hide
+ */
+public final class IpSecTransformResponse implements Parcelable {
+    private static final String TAG = "IpSecTransformResponse";
+
+    public final int resourceId;
+    public final int status;
+    // Parcelable Methods
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(status);
+        out.writeInt(resourceId);
+    }
+
+    public IpSecTransformResponse(int inStatus) {
+        if (inStatus == IpSecManager.Status.OK) {
+            throw new IllegalArgumentException("Valid status implies other args must be provided");
+        }
+        status = inStatus;
+        resourceId = IpSecManager.INVALID_RESOURCE_ID;
+    }
+
+    public IpSecTransformResponse(int inStatus, int inResourceId) {
+        status = inStatus;
+        resourceId = inResourceId;
+    }
+
+    private IpSecTransformResponse(Parcel in) {
+        status = in.readInt();
+        resourceId = in.readInt();
+    }
+
+    @android.annotation.NonNull
+    public static final Parcelable.Creator<IpSecTransformResponse> CREATOR =
+            new Parcelable.Creator<IpSecTransformResponse>() {
+                public IpSecTransformResponse createFromParcel(Parcel in) {
+                    return new IpSecTransformResponse(in);
+                }
+
+                public IpSecTransformResponse[] newArray(int size) {
+                    return new IpSecTransformResponse[size];
+                }
+            };
+}
diff --git a/framework-t/src/android/net/IpSecTunnelInterfaceResponse.aidl b/framework-t/src/android/net/IpSecTunnelInterfaceResponse.aidl
new file mode 100644
index 0000000..7239221
--- /dev/null
+++ b/framework-t/src/android/net/IpSecTunnelInterfaceResponse.aidl
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+parcelable IpSecTunnelInterfaceResponse;
diff --git a/framework-t/src/android/net/IpSecTunnelInterfaceResponse.java b/framework-t/src/android/net/IpSecTunnelInterfaceResponse.java
new file mode 100644
index 0000000..127e30a
--- /dev/null
+++ b/framework-t/src/android/net/IpSecTunnelInterfaceResponse.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * This class is used to return an IpSecTunnelInterface resource Id and and corresponding status
+ * from the IpSecService to an IpSecTunnelInterface object.
+ *
+ * @hide
+ */
+public final class IpSecTunnelInterfaceResponse implements Parcelable {
+    private static final String TAG = "IpSecTunnelInterfaceResponse";
+
+    public final int resourceId;
+    public final String interfaceName;
+    public final int status;
+    // Parcelable Methods
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(status);
+        out.writeInt(resourceId);
+        out.writeString(interfaceName);
+    }
+
+    public IpSecTunnelInterfaceResponse(int inStatus) {
+        if (inStatus == IpSecManager.Status.OK) {
+            throw new IllegalArgumentException("Valid status implies other args must be provided");
+        }
+        status = inStatus;
+        resourceId = IpSecManager.INVALID_RESOURCE_ID;
+        interfaceName = "";
+    }
+
+    public IpSecTunnelInterfaceResponse(int inStatus, int inResourceId, String inInterfaceName) {
+        status = inStatus;
+        resourceId = inResourceId;
+        interfaceName = inInterfaceName;
+    }
+
+    private IpSecTunnelInterfaceResponse(Parcel in) {
+        status = in.readInt();
+        resourceId = in.readInt();
+        interfaceName = in.readString();
+    }
+
+    @android.annotation.NonNull
+    public static final Parcelable.Creator<IpSecTunnelInterfaceResponse> CREATOR =
+            new Parcelable.Creator<IpSecTunnelInterfaceResponse>() {
+                public IpSecTunnelInterfaceResponse createFromParcel(Parcel in) {
+                    return new IpSecTunnelInterfaceResponse(in);
+                }
+
+                public IpSecTunnelInterfaceResponse[] newArray(int size) {
+                    return new IpSecTunnelInterfaceResponse[size];
+                }
+            };
+}
diff --git a/framework-t/src/android/net/IpSecUdpEncapResponse.aidl b/framework-t/src/android/net/IpSecUdpEncapResponse.aidl
new file mode 100644
index 0000000..5e451f3
--- /dev/null
+++ b/framework-t/src/android/net/IpSecUdpEncapResponse.aidl
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+parcelable IpSecUdpEncapResponse;
diff --git a/framework-t/src/android/net/IpSecUdpEncapResponse.java b/framework-t/src/android/net/IpSecUdpEncapResponse.java
new file mode 100644
index 0000000..732cf19
--- /dev/null
+++ b/framework-t/src/android/net/IpSecUdpEncapResponse.java
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.net;
+
+import android.os.Parcel;
+import android.os.ParcelFileDescriptor;
+import android.os.Parcelable;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+
+/**
+ * This class is used to return a UDP Socket and corresponding status from the IpSecService to an
+ * IpSecManager.UdpEncapsulationSocket.
+ *
+ * @hide
+ */
+public final class IpSecUdpEncapResponse implements Parcelable {
+    private static final String TAG = "IpSecUdpEncapResponse";
+
+    public final int resourceId;
+    public final int port;
+    public final int status;
+    // There is a weird asymmetry with FileDescriptor: you can write a FileDescriptor
+    // but you read a ParcelFileDescriptor. To circumvent this, when we receive a FD
+    // from the user, we immediately create a ParcelFileDescriptor DUP, which we invalidate
+    // on writeParcel() by setting the flag to do close-on-write.
+    // TODO: tests to ensure this doesn't leak
+    public final ParcelFileDescriptor fileDescriptor;
+
+    // Parcelable Methods
+
+    @Override
+    public int describeContents() {
+        return (fileDescriptor != null) ? Parcelable.CONTENTS_FILE_DESCRIPTOR : 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(status);
+        out.writeInt(resourceId);
+        out.writeInt(port);
+        out.writeParcelable(fileDescriptor, Parcelable.PARCELABLE_WRITE_RETURN_VALUE);
+    }
+
+    public IpSecUdpEncapResponse(int inStatus) {
+        if (inStatus == IpSecManager.Status.OK) {
+            throw new IllegalArgumentException("Valid status implies other args must be provided");
+        }
+        status = inStatus;
+        resourceId = IpSecManager.INVALID_RESOURCE_ID;
+        port = -1;
+        fileDescriptor = null; // yes I know it's redundant, but readability
+    }
+
+    public IpSecUdpEncapResponse(int inStatus, int inResourceId, int inPort, FileDescriptor inFd)
+            throws IOException {
+        if (inStatus == IpSecManager.Status.OK && inFd == null) {
+            throw new IllegalArgumentException("Valid status implies FD must be non-null");
+        }
+        status = inStatus;
+        resourceId = inResourceId;
+        port = inPort;
+        fileDescriptor = (status == IpSecManager.Status.OK) ? ParcelFileDescriptor.dup(inFd) : null;
+    }
+
+    private IpSecUdpEncapResponse(Parcel in) {
+        status = in.readInt();
+        resourceId = in.readInt();
+        port = in.readInt();
+        fileDescriptor = in.readParcelable(ParcelFileDescriptor.class.getClassLoader());
+    }
+
+    @android.annotation.NonNull
+    public static final Parcelable.Creator<IpSecUdpEncapResponse> CREATOR =
+            new Parcelable.Creator<IpSecUdpEncapResponse>() {
+                public IpSecUdpEncapResponse createFromParcel(Parcel in) {
+                    return new IpSecUdpEncapResponse(in);
+                }
+
+                public IpSecUdpEncapResponse[] newArray(int size) {
+                    return new IpSecUdpEncapResponse[size];
+                }
+            };
+}
diff --git a/framework-t/src/android/net/NetworkIdentity.java b/framework-t/src/android/net/NetworkIdentity.java
new file mode 100644
index 0000000..da5f88d
--- /dev/null
+++ b/framework-t/src/android/net/NetworkIdentity.java
@@ -0,0 +1,594 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.ConnectivityManager.TYPE_MOBILE;
+import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.net.NetworkTemplate.NETWORK_TYPE_ALL;
+import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SuppressLint;
+import android.annotation.SystemApi;
+import android.app.usage.NetworkStatsManager;
+import android.content.Context;
+import android.net.wifi.WifiInfo;
+import android.service.NetworkIdentityProto;
+import android.telephony.TelephonyManager;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.net.module.util.CollectionUtils;
+import com.android.net.module.util.NetworkCapabilitiesUtils;
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayList;
+import java.util.Objects;
+
+/**
+ * Network definition that includes strong identity. Analogous to combining
+ * {@link NetworkCapabilities} and an IMSI.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public class NetworkIdentity {
+    private static final String TAG = "NetworkIdentity";
+
+    /** @hide */
+    // TODO: Remove this after migrating all callers to use
+    //  {@link NetworkTemplate#NETWORK_TYPE_ALL} instead.
+    public static final int SUBTYPE_COMBINED = -1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "OEM_MANAGED_" }, flag = true, value = {
+            NetworkTemplate.OEM_MANAGED_NO,
+            NetworkTemplate.OEM_MANAGED_PAID,
+            NetworkTemplate.OEM_MANAGED_PRIVATE
+    })
+    public @interface OemManaged{}
+
+    /**
+     * Network has no {@code NetworkCapabilities#NET_CAPABILITY_OEM_*}.
+     * @hide
+     */
+    public static final int OEM_NONE = 0x0;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PAID}.
+     * @hide
+     */
+    public static final int OEM_PAID = 1 << 0;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PRIVATE}.
+     * @hide
+     */
+    public static final int OEM_PRIVATE = 1 << 1;
+
+    private static final long SUPPORTED_OEM_MANAGED_TYPES = OEM_PAID | OEM_PRIVATE;
+
+    final int mType;
+    final int mRatType;
+    final int mSubId;
+    final String mSubscriberId;
+    final String mWifiNetworkKey;
+    final boolean mRoaming;
+    final boolean mMetered;
+    final boolean mDefaultNetwork;
+    final int mOemManaged;
+
+    /** @hide */
+    public NetworkIdentity(
+            int type, int ratType, @Nullable String subscriberId, @Nullable String wifiNetworkKey,
+            boolean roaming, boolean metered, boolean defaultNetwork, int oemManaged, int subId) {
+        mType = type;
+        mRatType = ratType;
+        mSubscriberId = subscriberId;
+        mWifiNetworkKey = wifiNetworkKey;
+        mRoaming = roaming;
+        mMetered = metered;
+        mDefaultNetwork = defaultNetwork;
+        mOemManaged = oemManaged;
+        mSubId = subId;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mType, mRatType, mSubscriberId, mWifiNetworkKey, mRoaming, mMetered,
+                mDefaultNetwork, mOemManaged, mSubId);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof NetworkIdentity) {
+            final NetworkIdentity ident = (NetworkIdentity) obj;
+            return mType == ident.mType && mRatType == ident.mRatType && mRoaming == ident.mRoaming
+                    && Objects.equals(mSubscriberId, ident.mSubscriberId)
+                    && Objects.equals(mWifiNetworkKey, ident.mWifiNetworkKey)
+                    && mMetered == ident.mMetered
+                    && mDefaultNetwork == ident.mDefaultNetwork
+                    && mOemManaged == ident.mOemManaged
+                    && mSubId == ident.mSubId;
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder("{");
+        builder.append("type=").append(mType);
+        builder.append(", ratType=");
+        if (mRatType == NETWORK_TYPE_ALL) {
+            builder.append("COMBINED");
+        } else {
+            builder.append(mRatType);
+        }
+        if (mSubscriberId != null) {
+            builder.append(", subscriberId=")
+                    .append(NetworkIdentityUtils.scrubSubscriberId(mSubscriberId));
+        }
+        if (mWifiNetworkKey != null) {
+            builder.append(", wifiNetworkKey=").append(mWifiNetworkKey);
+        }
+        if (mRoaming) {
+            builder.append(", ROAMING");
+        }
+        builder.append(", metered=").append(mMetered);
+        builder.append(", defaultNetwork=").append(mDefaultNetwork);
+        builder.append(", oemManaged=").append(getOemManagedNames(mOemManaged));
+        builder.append(", subId=").append(mSubId);
+        return builder.append("}").toString();
+    }
+
+    /**
+     * Get the human readable representation of a bitfield representing the OEM managed state of a
+     * network.
+     */
+    static String getOemManagedNames(int oemManaged) {
+        if (oemManaged == OEM_NONE) {
+            return "OEM_NONE";
+        }
+        final int[] bitPositions = NetworkCapabilitiesUtils.unpackBits(oemManaged);
+        final ArrayList<String> oemManagedNames = new ArrayList<String>();
+        for (int position : bitPositions) {
+            oemManagedNames.add(nameOfOemManaged(1 << position));
+        }
+        return String.join(",", oemManagedNames);
+    }
+
+    private static String nameOfOemManaged(int oemManagedBit) {
+        switch (oemManagedBit) {
+            case OEM_PAID:
+                return "OEM_PAID";
+            case OEM_PRIVATE:
+                return "OEM_PRIVATE";
+            default:
+                return "Invalid(" + oemManagedBit + ")";
+        }
+    }
+
+    /** @hide */
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        proto.write(NetworkIdentityProto.TYPE, mType);
+
+        // TODO: dump mRatType as well.
+
+        proto.write(NetworkIdentityProto.ROAMING, mRoaming);
+        proto.write(NetworkIdentityProto.METERED, mMetered);
+        proto.write(NetworkIdentityProto.DEFAULT_NETWORK, mDefaultNetwork);
+        proto.write(NetworkIdentityProto.OEM_MANAGED_NETWORK, mOemManaged);
+
+        proto.end(start);
+    }
+
+    /** Get the network type of this instance. */
+    public int getType() {
+        return mType;
+    }
+
+    /** Get the Radio Access Technology(RAT) type of this instance. */
+    public int getRatType() {
+        return mRatType;
+    }
+
+    /** Get the Subscriber Id of this instance. */
+    @Nullable
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    /** Get the Wifi Network Key of this instance. See {@link WifiInfo#getNetworkKey()}. */
+    @Nullable
+    public String getWifiNetworkKey() {
+        return mWifiNetworkKey;
+    }
+
+    /** @hide */
+    // TODO: Remove this function after all callers are removed.
+    public boolean getRoaming() {
+        return mRoaming;
+    }
+
+    /** Return whether this network is roaming. */
+    public boolean isRoaming() {
+        return mRoaming;
+    }
+
+    /** @hide */
+    // TODO: Remove this function after all callers are removed.
+    public boolean getMetered() {
+        return mMetered;
+    }
+
+    /** Return whether this network is metered. */
+    public boolean isMetered() {
+        return mMetered;
+    }
+
+    /** @hide */
+    // TODO: Remove this function after all callers are removed.
+    public boolean getDefaultNetwork() {
+        return mDefaultNetwork;
+    }
+
+    /** Return whether this network is the default network. */
+    public boolean isDefaultNetwork() {
+        return mDefaultNetwork;
+    }
+
+    /** Get the OEM managed type of this instance. */
+    public int getOemManaged() {
+        return mOemManaged;
+    }
+
+    /** Get the SubId of this instance. */
+    public int getSubId() {
+        return mSubId;
+    }
+
+    /**
+     * Assemble a {@link NetworkIdentity} from the passed arguments.
+     *
+     * This methods builds an identity based on the capabilities of the network in the
+     * snapshot and other passed arguments. The identity is used as a key to record data usage.
+     *
+     * @param snapshot the snapshot of network state. See {@link NetworkStateSnapshot}.
+     * @param defaultNetwork whether the network is a default network.
+     * @param ratType the Radio Access Technology(RAT) type of the network. Or
+     *                {@link TelephonyManager#NETWORK_TYPE_UNKNOWN} if not applicable.
+     *                See {@code TelephonyManager.NETWORK_TYPE_*}.
+     * @hide
+     * @deprecated See {@link NetworkIdentity.Builder}.
+     */
+    // TODO: Remove this after all callers are migrated to use new Api.
+    @Deprecated
+    @NonNull
+    public static NetworkIdentity buildNetworkIdentity(Context context,
+            @NonNull NetworkStateSnapshot snapshot, boolean defaultNetwork, int ratType) {
+        final NetworkIdentity.Builder builder = new NetworkIdentity.Builder()
+                .setNetworkStateSnapshot(snapshot).setDefaultNetwork(defaultNetwork)
+                .setSubId(snapshot.getSubId());
+        if (snapshot.getLegacyType() == TYPE_MOBILE && ratType != NETWORK_TYPE_ALL) {
+            builder.setRatType(ratType);
+        }
+        return builder.build();
+    }
+
+    /**
+     * Builds a bitfield of {@code NetworkIdentity.OEM_*} based on {@link NetworkCapabilities}.
+     * @hide
+     */
+    public static int getOemBitfield(@NonNull NetworkCapabilities nc) {
+        int oemManaged = OEM_NONE;
+
+        if (nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_OEM_PAID)) {
+            oemManaged |= OEM_PAID;
+        }
+        if (nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_OEM_PRIVATE)) {
+            oemManaged |= OEM_PRIVATE;
+        }
+
+        return oemManaged;
+    }
+
+    /** @hide */
+    public static int compare(@NonNull NetworkIdentity left, @NonNull NetworkIdentity right) {
+        Objects.requireNonNull(right);
+        int res = Integer.compare(left.mType, right.mType);
+        if (res == 0) {
+            res = Integer.compare(left.mRatType, right.mRatType);
+        }
+        if (res == 0 && left.mSubscriberId != null && right.mSubscriberId != null) {
+            res = left.mSubscriberId.compareTo(right.mSubscriberId);
+        }
+        if (res == 0 && left.mWifiNetworkKey != null && right.mWifiNetworkKey != null) {
+            res = left.mWifiNetworkKey.compareTo(right.mWifiNetworkKey);
+        }
+        if (res == 0) {
+            res = Boolean.compare(left.mRoaming, right.mRoaming);
+        }
+        if (res == 0) {
+            res = Boolean.compare(left.mMetered, right.mMetered);
+        }
+        if (res == 0) {
+            res = Boolean.compare(left.mDefaultNetwork, right.mDefaultNetwork);
+        }
+        if (res == 0) {
+            res = Integer.compare(left.mOemManaged, right.mOemManaged);
+        }
+        if (res == 0) {
+            res = Integer.compare(left.mSubId, right.mSubId);
+        }
+        return res;
+    }
+
+    /**
+     * Builder class for {@link NetworkIdentity}.
+     */
+    public static final class Builder {
+        // Need to be synchronized with ConnectivityManager.
+        // TODO: Use {@link ConnectivityManager#MAX_NETWORK_TYPE} when this file is in the module.
+        private static final int MAX_NETWORK_TYPE = 18; // TYPE_TEST
+        private static final int MIN_NETWORK_TYPE = TYPE_MOBILE;
+
+        private int mType;
+        private int mRatType;
+        private String mSubscriberId;
+        private String mWifiNetworkKey;
+        private boolean mRoaming;
+        private boolean mMetered;
+        private boolean mDefaultNetwork;
+        private int mOemManaged;
+        private int mSubId;
+
+        /**
+         * Creates a new Builder.
+         */
+        public Builder() {
+            // Initialize with default values. Will be overwritten by setters.
+            mType = ConnectivityManager.TYPE_NONE;
+            mRatType = NetworkTemplate.NETWORK_TYPE_ALL;
+            mSubscriberId = null;
+            mWifiNetworkKey = null;
+            mRoaming = false;
+            mMetered = false;
+            mDefaultNetwork = false;
+            mOemManaged = NetworkTemplate.OEM_MANAGED_NO;
+            mSubId = INVALID_SUBSCRIPTION_ID;
+        }
+
+        /**
+         * Add an {@link NetworkStateSnapshot} into the {@link NetworkIdentity} instance.
+         * This is a useful shorthand that will read from the snapshot and set the
+         * following fields, if they are set in the snapshot :
+         *  - type
+         *  - subscriberId
+         *  - roaming
+         *  - metered
+         *  - oemManaged
+         *  - wifiNetworkKey
+         *
+         * @param snapshot The target {@link NetworkStateSnapshot} object.
+         * @return The builder object.
+         */
+        @SuppressLint("MissingGetterMatchingBuilder")
+        @NonNull
+        public Builder setNetworkStateSnapshot(@NonNull NetworkStateSnapshot snapshot) {
+            setType(snapshot.getLegacyType());
+
+            setSubscriberId(snapshot.getSubscriberId());
+            setRoaming(!snapshot.getNetworkCapabilities().hasCapability(
+                    NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING));
+            setMetered(!(snapshot.getNetworkCapabilities().hasCapability(
+                    NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
+                    || snapshot.getNetworkCapabilities().hasCapability(
+                    NetworkCapabilities.NET_CAPABILITY_TEMPORARILY_NOT_METERED)));
+
+            setOemManaged(getOemBitfield(snapshot.getNetworkCapabilities()));
+
+            if (mType == TYPE_WIFI) {
+                final TransportInfo transportInfo = snapshot.getNetworkCapabilities()
+                        .getTransportInfo();
+                if (transportInfo instanceof WifiInfo) {
+                    final WifiInfo info = (WifiInfo) transportInfo;
+                    setWifiNetworkKey(info.getNetworkKey());
+                }
+            }
+            return this;
+        }
+
+        /**
+         * Set the network type of the network.
+         *
+         * @param type the network type. See {@link ConnectivityManager#TYPE_*}.
+         *
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setType(int type) {
+            // Include TYPE_NONE for compatibility, type field might not be filled by some
+            // networks such as test networks.
+            if ((type < MIN_NETWORK_TYPE || MAX_NETWORK_TYPE < type)
+                    && type != ConnectivityManager.TYPE_NONE) {
+                throw new IllegalArgumentException("Invalid network type: " + type);
+            }
+            mType = type;
+            return this;
+        }
+
+        /**
+         * Set the Radio Access Technology(RAT) type of the network.
+         *
+         * No RAT type is specified by default. Call clearRatType to reset.
+         *
+         * @param ratType the Radio Access Technology(RAT) type if applicable. See
+         *                {@code TelephonyManager.NETWORK_TYPE_*}.
+         *
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setRatType(int ratType) {
+            if (!CollectionUtils.contains(TelephonyManager.getAllNetworkTypes(), ratType)
+                    && ratType != TelephonyManager.NETWORK_TYPE_UNKNOWN
+                    && ratType != NetworkStatsManager.NETWORK_TYPE_5G_NSA) {
+                throw new IllegalArgumentException("Invalid ratType " + ratType);
+            }
+            mRatType = ratType;
+            return this;
+        }
+
+        /**
+         * Clear the Radio Access Technology(RAT) type of the network.
+         *
+         * @return this builder.
+         */
+        @NonNull
+        public Builder clearRatType() {
+            mRatType = NetworkTemplate.NETWORK_TYPE_ALL;
+            return this;
+        }
+
+        /**
+         * Set the Subscriber Id.
+         *
+         * @param subscriberId the Subscriber Id of the network. Or null if not applicable.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setSubscriberId(@Nullable String subscriberId) {
+            mSubscriberId = subscriberId;
+            return this;
+        }
+
+        /**
+         * Set the Wifi Network Key.
+         *
+         * @param wifiNetworkKey Wifi Network Key of the network,
+         *                        see {@link WifiInfo#getNetworkKey()}.
+         *                        Or null if not applicable.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setWifiNetworkKey(@Nullable String wifiNetworkKey) {
+            mWifiNetworkKey = wifiNetworkKey;
+            return this;
+        }
+
+        /**
+         * Set whether this network is roaming.
+         *
+         * This field is false by default. Call with false to reset.
+         *
+         * @param roaming the roaming status of the network.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setRoaming(boolean roaming) {
+            mRoaming = roaming;
+            return this;
+        }
+
+        /**
+         * Set whether this network is metered.
+         *
+         * This field is false by default. Call with false to reset.
+         *
+         * @param metered the meteredness of the network.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setMetered(boolean metered) {
+            mMetered = metered;
+            return this;
+        }
+
+        /**
+         * Set whether this network is the default network.
+         *
+         * This field is false by default. Call with false to reset.
+         *
+         * @param defaultNetwork the default network status of the network.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setDefaultNetwork(boolean defaultNetwork) {
+            mDefaultNetwork = defaultNetwork;
+            return this;
+        }
+
+        /**
+         * Set the OEM managed type.
+         *
+         * @param oemManaged Type of OEM managed network or unmanaged networks.
+         *                   See {@code NetworkTemplate#OEM_MANAGED_*}.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setOemManaged(@OemManaged int oemManaged) {
+            // Assert input does not contain illegal oemManage bits.
+            if ((~SUPPORTED_OEM_MANAGED_TYPES & oemManaged) != 0) {
+                throw new IllegalArgumentException("Invalid value for OemManaged : " + oemManaged);
+            }
+            mOemManaged = oemManaged;
+            return this;
+        }
+
+        /**
+         * Set the Subscription Id.
+         *
+         * @param subId the Subscription Id of the network. Or INVALID_SUBSCRIPTION_ID if not
+         *              applicable.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setSubId(int subId) {
+            mSubId = subId;
+            return this;
+        }
+
+        private void ensureValidParameters() {
+            // Assert non-mobile network cannot have a ratType.
+            if (mType != TYPE_MOBILE && mRatType != NetworkTemplate.NETWORK_TYPE_ALL) {
+                throw new IllegalArgumentException(
+                        "Invalid ratType " + mRatType + " for type " + mType);
+            }
+
+            // Assert non-wifi network cannot have a wifi network key.
+            if (mType != TYPE_WIFI && mWifiNetworkKey != null) {
+                throw new IllegalArgumentException("Invalid wifi network key for type " + mType);
+            }
+        }
+
+        /**
+         * Builds the instance of the {@link NetworkIdentity}.
+         *
+         * @return the built instance of {@link NetworkIdentity}.
+         */
+        @NonNull
+        public NetworkIdentity build() {
+            ensureValidParameters();
+            return new NetworkIdentity(mType, mRatType, mSubscriberId, mWifiNetworkKey,
+                    mRoaming, mMetered, mDefaultNetwork, mOemManaged, mSubId);
+        }
+    }
+}
diff --git a/framework-t/src/android/net/NetworkIdentitySet.java b/framework-t/src/android/net/NetworkIdentitySet.java
new file mode 100644
index 0000000..ad3a958
--- /dev/null
+++ b/framework-t/src/android/net/NetworkIdentitySet.java
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.net.ConnectivityManager.TYPE_MOBILE;
+import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
+
+import android.annotation.NonNull;
+import android.service.NetworkIdentitySetProto;
+import android.util.proto.ProtoOutputStream;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * Identity of a {@code iface}, defined by the set of {@link NetworkIdentity}
+ * active on that interface.
+ *
+ * @hide
+ */
+public class NetworkIdentitySet extends HashSet<NetworkIdentity> {
+    private static final int VERSION_INIT = 1;
+    private static final int VERSION_ADD_ROAMING = 2;
+    private static final int VERSION_ADD_NETWORK_ID = 3;
+    private static final int VERSION_ADD_METERED = 4;
+    private static final int VERSION_ADD_DEFAULT_NETWORK = 5;
+    private static final int VERSION_ADD_OEM_MANAGED_NETWORK = 6;
+    private static final int VERSION_ADD_SUB_ID = 7;
+
+    /**
+     * Construct a {@link NetworkIdentitySet} object.
+     */
+    public NetworkIdentitySet() {
+        super();
+    }
+
+    /** @hide */
+    public NetworkIdentitySet(@NonNull Set<NetworkIdentity> ident) {
+        super(ident);
+    }
+
+    /** @hide */
+    public NetworkIdentitySet(DataInput in) throws IOException {
+        final int version = in.readInt();
+        final int size = in.readInt();
+        for (int i = 0; i < size; i++) {
+            if (version <= VERSION_INIT) {
+                final int ignored = in.readInt();
+            }
+            final int type = in.readInt();
+            final int ratType = in.readInt();
+            final String subscriberId = readOptionalString(in);
+            final String networkId;
+            if (version >= VERSION_ADD_NETWORK_ID) {
+                networkId = readOptionalString(in);
+            } else {
+                networkId = null;
+            }
+            final boolean roaming;
+            if (version >= VERSION_ADD_ROAMING) {
+                roaming = in.readBoolean();
+            } else {
+                roaming = false;
+            }
+
+            final boolean metered;
+            if (version >= VERSION_ADD_METERED) {
+                metered = in.readBoolean();
+            } else {
+                // If this is the old data and the type is mobile, treat it as metered. (Note that
+                // if this is a mobile network, TYPE_MOBILE is the only possible type that could be
+                // used.)
+                metered = (type == TYPE_MOBILE);
+            }
+
+            final boolean defaultNetwork;
+            if (version >= VERSION_ADD_DEFAULT_NETWORK) {
+                defaultNetwork = in.readBoolean();
+            } else {
+                defaultNetwork = true;
+            }
+
+            final int oemNetCapabilities;
+            if (version >= VERSION_ADD_OEM_MANAGED_NETWORK) {
+                oemNetCapabilities = in.readInt();
+            } else {
+                oemNetCapabilities = NetworkIdentity.OEM_NONE;
+            }
+
+            final int subId;
+            if (version >= VERSION_ADD_SUB_ID) {
+                subId = in.readInt();
+            } else {
+                subId = INVALID_SUBSCRIPTION_ID;
+            }
+
+            add(new NetworkIdentity(type, ratType, subscriberId, networkId, roaming, metered,
+                    defaultNetwork, oemNetCapabilities, subId));
+        }
+    }
+
+    /**
+     * Method to serialize this object into a {@code DataOutput}.
+     * @hide
+     */
+    public void writeToStream(DataOutput out) throws IOException {
+        out.writeInt(VERSION_ADD_SUB_ID);
+        out.writeInt(size());
+        for (NetworkIdentity ident : this) {
+            out.writeInt(ident.getType());
+            out.writeInt(ident.getRatType());
+            writeOptionalString(out, ident.getSubscriberId());
+            writeOptionalString(out, ident.getWifiNetworkKey());
+            out.writeBoolean(ident.isRoaming());
+            out.writeBoolean(ident.isMetered());
+            out.writeBoolean(ident.isDefaultNetwork());
+            out.writeInt(ident.getOemManaged());
+            out.writeInt(ident.getSubId());
+        }
+    }
+
+    /**
+     * @return whether any {@link NetworkIdentity} in this set is considered metered.
+     * @hide
+     */
+    public boolean isAnyMemberMetered() {
+        if (isEmpty()) {
+            return false;
+        }
+        for (NetworkIdentity ident : this) {
+            if (ident.isMetered()) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * @return whether any {@link NetworkIdentity} in this set is considered roaming.
+     * @hide
+     */
+    public boolean isAnyMemberRoaming() {
+        if (isEmpty()) {
+            return false;
+        }
+        for (NetworkIdentity ident : this) {
+            if (ident.isRoaming()) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * @return whether any {@link NetworkIdentity} in this set is considered on the default
+     *         network.
+     * @hide
+     */
+    public boolean areAllMembersOnDefaultNetwork() {
+        if (isEmpty()) {
+            return true;
+        }
+        for (NetworkIdentity ident : this) {
+            if (!ident.isDefaultNetwork()) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static void writeOptionalString(DataOutput out, String value) throws IOException {
+        if (value != null) {
+            out.writeByte(1);
+            out.writeUTF(value);
+        } else {
+            out.writeByte(0);
+        }
+    }
+
+    private static String readOptionalString(DataInput in) throws IOException {
+        if (in.readByte() != 0) {
+            return in.readUTF();
+        } else {
+            return null;
+        }
+    }
+
+    public static int compare(@NonNull NetworkIdentitySet left, @NonNull NetworkIdentitySet right) {
+        Objects.requireNonNull(left);
+        Objects.requireNonNull(right);
+        if (left.isEmpty()) return -1;
+        if (right.isEmpty()) return 1;
+
+        final NetworkIdentity leftIdent = left.iterator().next();
+        final NetworkIdentity rightIdent = right.iterator().next();
+        return NetworkIdentity.compare(leftIdent, rightIdent);
+    }
+
+    /**
+     * Method to dump this object into proto debug file.
+     * @hide
+     */
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        for (NetworkIdentity ident : this) {
+            ident.dumpDebug(proto, NetworkIdentitySetProto.IDENTITIES);
+        }
+
+        proto.end(start);
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStateSnapshot.java b/framework-t/src/android/net/NetworkStateSnapshot.java
new file mode 100644
index 0000000..d3f785a
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStateSnapshot.java
@@ -0,0 +1,192 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
+import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.util.Objects;
+
+/**
+ * Snapshot of network state.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class NetworkStateSnapshot implements Parcelable {
+    /** The network associated with this snapshot. */
+    @NonNull
+    private final Network mNetwork;
+
+    /** The {@link NetworkCapabilities} of the network associated with this snapshot. */
+    @NonNull
+    private final NetworkCapabilities mNetworkCapabilities;
+
+    /** The {@link LinkProperties} of the network associated with this snapshot. */
+    @NonNull
+    private final LinkProperties mLinkProperties;
+
+    /**
+     * The Subscriber Id of the network associated with this snapshot. See
+     * {@link android.telephony.TelephonyManager#getSubscriberId()}.
+     */
+    @Nullable
+    private final String mSubscriberId;
+
+    /**
+     * The legacy type of the network associated with this snapshot. See
+     * {@code ConnectivityManager#TYPE_*}.
+     */
+    private final int mLegacyType;
+
+    public NetworkStateSnapshot(@NonNull Network network,
+            @NonNull NetworkCapabilities networkCapabilities,
+            @NonNull LinkProperties linkProperties,
+            @Nullable String subscriberId, int legacyType) {
+        mNetwork = Objects.requireNonNull(network);
+        mNetworkCapabilities = Objects.requireNonNull(networkCapabilities);
+        mLinkProperties = Objects.requireNonNull(linkProperties);
+        mSubscriberId = subscriberId;
+        mLegacyType = legacyType;
+    }
+
+    /** @hide */
+    public NetworkStateSnapshot(@NonNull Parcel in) {
+        mNetwork = in.readParcelable(null);
+        mNetworkCapabilities = in.readParcelable(null);
+        mLinkProperties = in.readParcelable(null);
+        mSubscriberId = in.readString();
+        mLegacyType = in.readInt();
+    }
+
+    /** Get the network associated with this snapshot */
+    @NonNull
+    public Network getNetwork() {
+        return mNetwork;
+    }
+
+    /** Get {@link NetworkCapabilities} of the network associated with this snapshot. */
+    @NonNull
+    public NetworkCapabilities getNetworkCapabilities() {
+        return mNetworkCapabilities;
+    }
+
+    /** Get the {@link LinkProperties} of the network associated with this snapshot. */
+    @NonNull
+    public LinkProperties getLinkProperties() {
+        return mLinkProperties;
+    }
+
+    /**
+     * Get the Subscriber Id of the network associated with this snapshot.
+     * @deprecated Please use #getSubId, which doesn't return personally identifiable
+     * information.
+     */
+    @Deprecated
+    @Nullable
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    /** Get the subId of the network associated with this snapshot. */
+    public int getSubId() {
+        if (mNetworkCapabilities.hasTransport(TRANSPORT_CELLULAR)) {
+            final NetworkSpecifier spec = mNetworkCapabilities.getNetworkSpecifier();
+            if (spec instanceof TelephonyNetworkSpecifier) {
+                return ((TelephonyNetworkSpecifier) spec).getSubscriptionId();
+            }
+        }
+        return INVALID_SUBSCRIPTION_ID;
+    }
+
+
+    /**
+     * Get the legacy type of the network associated with this snapshot.
+     * @return the legacy network type. See {@code ConnectivityManager#TYPE_*}.
+     */
+    public int getLegacyType() {
+        return mLegacyType;
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel out, int flags) {
+        out.writeParcelable(mNetwork, flags);
+        out.writeParcelable(mNetworkCapabilities, flags);
+        out.writeParcelable(mLinkProperties, flags);
+        out.writeString(mSubscriberId);
+        out.writeInt(mLegacyType);
+    }
+
+    @NonNull
+    public static final Creator<NetworkStateSnapshot> CREATOR =
+            new Creator<NetworkStateSnapshot>() {
+        @NonNull
+        @Override
+        public NetworkStateSnapshot createFromParcel(@NonNull Parcel in) {
+            return new NetworkStateSnapshot(in);
+        }
+
+        @NonNull
+        @Override
+        public NetworkStateSnapshot[] newArray(int size) {
+            return new NetworkStateSnapshot[size];
+        }
+    };
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof NetworkStateSnapshot)) return false;
+        NetworkStateSnapshot that = (NetworkStateSnapshot) o;
+        return mLegacyType == that.mLegacyType
+                && Objects.equals(mNetwork, that.mNetwork)
+                && Objects.equals(mNetworkCapabilities, that.mNetworkCapabilities)
+                && Objects.equals(mLinkProperties, that.mLinkProperties)
+                && Objects.equals(mSubscriberId, that.mSubscriberId);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mNetwork,
+                mNetworkCapabilities, mLinkProperties, mSubscriberId, mLegacyType);
+    }
+
+    @Override
+    public String toString() {
+        return "NetworkStateSnapshot{"
+                + "network=" + mNetwork
+                + ", networkCapabilities=" + mNetworkCapabilities
+                + ", linkProperties=" + mLinkProperties
+                + ", subscriberId='" + NetworkIdentityUtils.scrubSubscriberId(mSubscriberId) + '\''
+                + ", legacyType=" + mLegacyType
+                + '}';
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStats.java b/framework-t/src/android/net/NetworkStats.java
new file mode 100644
index 0000000..06f2a62
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStats.java
@@ -0,0 +1,1834 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static com.android.net.module.util.NetworkStatsUtils.multiplySafeByRational;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.os.Process;
+import android.os.SystemClock;
+import android.text.TextUtils;
+import android.util.SparseBooleanArray;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.CollectionUtils;
+
+import libcore.util.EmptyArray;
+
+import java.io.CharArrayWriter;
+import java.io.PrintWriter;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * Collection of active network statistics. Can contain summary details across
+ * all interfaces, or details with per-UID granularity. Internally stores data
+ * as a large table, closely matching {@code /proc/} data format. This structure
+ * optimizes for rapid in-memory comparison, but consider using
+ * {@link NetworkStatsHistory} when persisting.
+ *
+ * @hide
+ */
+// @NotThreadSafe
+@SystemApi
+public final class NetworkStats implements Parcelable, Iterable<NetworkStats.Entry> {
+    private static final String TAG = "NetworkStats";
+
+    /**
+     * {@link #iface} value when interface details unavailable.
+     * @hide
+     */
+    @Nullable public static final String IFACE_ALL = null;
+
+    /**
+     * Virtual network interface for video telephony. This is for VT data usage counting
+     * purpose.
+     */
+    public static final String IFACE_VT = "vt_data0";
+
+    /** {@link #uid} value when UID details unavailable. */
+    public static final int UID_ALL = -1;
+    /** Special UID value for data usage by tethering. */
+    public static final int UID_TETHERING = -5;
+
+    /**
+     * {@link #tag} value matching any tag.
+     * @hide
+     */
+    // TODO: Rename TAG_ALL to TAG_ANY.
+    public static final int TAG_ALL = -1;
+    /** {@link #set} value for all sets combined, not including debug sets. */
+    public static final int SET_ALL = -1;
+    /** {@link #set} value where background data is accounted. */
+    public static final int SET_DEFAULT = 0;
+    /** {@link #set} value where foreground data is accounted. */
+    public static final int SET_FOREGROUND = 1;
+    /**
+     * All {@link #set} value greater than SET_DEBUG_START are debug {@link #set} values.
+     * @hide
+     */
+    public static final int SET_DEBUG_START = 1000;
+    /**
+     * Debug {@link #set} value when the VPN stats are moved in.
+     * @hide
+     */
+    public static final int SET_DBG_VPN_IN = 1001;
+    /**
+     * Debug {@link #set} value when the VPN stats are moved out of a vpn UID.
+     * @hide
+     */
+    public static final int SET_DBG_VPN_OUT = 1002;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "SET_" }, value = {
+            SET_ALL,
+            SET_DEFAULT,
+            SET_FOREGROUND,
+    })
+    public @interface State {
+    }
+
+    /**
+     * Include all interfaces when filtering
+     * @hide
+     */
+    public @Nullable static final String[] INTERFACES_ALL = null;
+
+    /** {@link #tag} value for total data across all tags. */
+    // TODO: Rename TAG_NONE to TAG_ALL.
+    public static final int TAG_NONE = 0;
+
+    /** {@link #metered} value to account for all metered states. */
+    public static final int METERED_ALL = -1;
+    /** {@link #metered} value where native, unmetered data is accounted. */
+    public static final int METERED_NO = 0;
+    /** {@link #metered} value where metered data is accounted. */
+    public static final int METERED_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "METERED_" }, value = {
+            METERED_ALL,
+            METERED_NO,
+            METERED_YES
+    })
+    public @interface Meteredness {
+    }
+
+
+    /** {@link #roaming} value to account for all roaming states. */
+    public static final int ROAMING_ALL = -1;
+    /** {@link #roaming} value where native, non-roaming data is accounted. */
+    public static final int ROAMING_NO = 0;
+    /** {@link #roaming} value where roaming data is accounted. */
+    public static final int ROAMING_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "ROAMING_" }, value = {
+            ROAMING_ALL,
+            ROAMING_NO,
+            ROAMING_YES
+    })
+    public @interface Roaming {
+    }
+
+    /** {@link #onDefaultNetwork} value to account for all default network states. */
+    public static final int DEFAULT_NETWORK_ALL = -1;
+    /** {@link #onDefaultNetwork} value to account for usage while not the default network. */
+    public static final int DEFAULT_NETWORK_NO = 0;
+    /** {@link #onDefaultNetwork} value to account for usage while the default network. */
+    public static final int DEFAULT_NETWORK_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "DEFAULT_NETWORK_" }, value = {
+            DEFAULT_NETWORK_ALL,
+            DEFAULT_NETWORK_NO,
+            DEFAULT_NETWORK_YES
+    })
+    public @interface DefaultNetwork {
+    }
+
+    /**
+     * Denotes a request for stats at the interface level.
+     * @hide
+     */
+    public static final int STATS_PER_IFACE = 0;
+    /**
+     * Denotes a request for stats at the interface and UID level.
+     * @hide
+     */
+    public static final int STATS_PER_UID = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "STATS_PER_" }, value = {
+            STATS_PER_IFACE,
+            STATS_PER_UID
+    })
+    public @interface StatsType {
+    }
+
+    private static final String CLATD_INTERFACE_PREFIX = "v4-";
+    // Delta between IPv4 header (20b) and IPv6 header (40b).
+    // Used for correct stats accounting on clatd interfaces.
+    private static final int IPV4V6_HEADER_DELTA = 20;
+
+    // TODO: move fields to "mVariable" notation
+
+    /**
+     * {@link SystemClock#elapsedRealtime()} timestamp in milliseconds when this data was
+     * generated.
+     * It's a timestamps delta when {@link #subtract()},
+     * {@code INetworkStatsSession#getSummaryForAllUid()} methods are used.
+     */
+    private long elapsedRealtime;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int size;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int capacity;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private String[] iface;
+    @UnsupportedAppUsage
+    private int[] uid;
+    @UnsupportedAppUsage
+    private int[] set;
+    @UnsupportedAppUsage
+    private int[] tag;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] metered;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] roaming;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] defaultNetwork;
+    @UnsupportedAppUsage
+    private long[] rxBytes;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] rxPackets;
+    @UnsupportedAppUsage
+    private long[] txBytes;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] txPackets;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] operations;
+
+    /**
+     * Basic element of network statistics. Contains the number of packets and number of bytes
+     * transferred on both directions in a given set of conditions. See
+     * {@link Entry#Entry(String, int, int, int, int, int, int, long, long, long, long, long)}.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static class Entry {
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public String iface;
+        /** @hide */
+        @UnsupportedAppUsage
+        public int uid;
+        /** @hide */
+        @UnsupportedAppUsage
+        public int set;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public int tag;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int metered;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int roaming;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int defaultNetwork;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long rxBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long rxPackets;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long txBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long txPackets;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long operations;
+
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public Entry() {
+            this(IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        }
+
+        /** @hide */
+        public Entry(long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+            this(IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, rxPackets, txBytes, txPackets,
+                    operations);
+        }
+
+        /** @hide */
+        public Entry(String iface, int uid, int set, int tag, long rxBytes, long rxPackets,
+                long txBytes, long txPackets, long operations) {
+            this(iface, uid, set, tag, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO,
+                    rxBytes, rxPackets, txBytes, txPackets, operations);
+        }
+
+        /**
+         * Construct a {@link Entry} object by giving statistics of packet and byte transferred on
+         * both direction, and associated with a set of given conditions.
+         *
+         * @param iface interface name of this {@link Entry}. Or null if not specified.
+         * @param uid uid of this {@link Entry}. {@link #UID_TETHERING} if this {@link Entry} is
+         *            for tethering. Or {@link #UID_ALL} if this {@link NetworkStats} is only
+         *            counting iface stats.
+         * @param set usage state of this {@link Entry}.
+         * @param tag tag of this {@link Entry}.
+         * @param metered metered state of this {@link Entry}.
+         * @param roaming roaming state of this {@link Entry}.
+         * @param defaultNetwork default network status of this {@link Entry}.
+         * @param rxBytes Number of bytes received for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param rxPackets Number of packets received for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param txBytes Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param txPackets Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param operations count of network operations performed for this {@link Entry}. This can
+         *                   be used to derive bytes-per-operation.
+         */
+        public Entry(@Nullable String iface, int uid, @State int set, int tag,
+                @Meteredness int metered, @Roaming int roaming, @DefaultNetwork int defaultNetwork,
+                long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+            this.iface = iface;
+            this.uid = uid;
+            this.set = set;
+            this.tag = tag;
+            this.metered = metered;
+            this.roaming = roaming;
+            this.defaultNetwork = defaultNetwork;
+            this.rxBytes = rxBytes;
+            this.rxPackets = rxPackets;
+            this.txBytes = txBytes;
+            this.txPackets = txPackets;
+            this.operations = operations;
+        }
+
+        /** @hide */
+        public boolean isNegative() {
+            return rxBytes < 0 || rxPackets < 0 || txBytes < 0 || txPackets < 0 || operations < 0;
+        }
+
+        /** @hide */
+        public boolean isEmpty() {
+            return rxBytes == 0 && rxPackets == 0 && txBytes == 0 && txPackets == 0
+                    && operations == 0;
+        }
+
+        /** @hide */
+        public void add(Entry another) {
+            this.rxBytes += another.rxBytes;
+            this.rxPackets += another.rxPackets;
+            this.txBytes += another.txBytes;
+            this.txPackets += another.txPackets;
+            this.operations += another.operations;
+        }
+
+        /**
+         * @return interface name of this entry.
+         * @hide
+         */
+        @Nullable public String getIface() {
+            return iface;
+        }
+
+        /**
+         * @return the uid of this entry.
+         */
+        public int getUid() {
+            return uid;
+        }
+
+        /**
+         * @return the set state of this entry.
+         */
+        @State public int getSet() {
+            return set;
+        }
+
+        /**
+         * @return the tag value of this entry.
+         */
+        public int getTag() {
+            return tag;
+        }
+
+        /**
+         * @return the metered state.
+         */
+        @Meteredness public int getMetered() {
+            return metered;
+        }
+
+        /**
+         * @return the roaming state.
+         */
+        @Roaming public int getRoaming() {
+            return roaming;
+        }
+
+        /**
+         * @return the default network state.
+         */
+        @DefaultNetwork public int getDefaultNetwork() {
+            return defaultNetwork;
+        }
+
+        /**
+         * @return the number of received bytes.
+         */
+        public long getRxBytes() {
+            return rxBytes;
+        }
+
+        /**
+         * @return the number of received packets.
+         */
+        public long getRxPackets() {
+            return rxPackets;
+        }
+
+        /**
+         * @return the number of transmitted bytes.
+         */
+        public long getTxBytes() {
+            return txBytes;
+        }
+
+        /**
+         * @return the number of transmitted packets.
+         */
+        public long getTxPackets() {
+            return txPackets;
+        }
+
+        /**
+         * @return the count of network operations performed for this entry.
+         */
+        public long getOperations() {
+            return operations;
+        }
+
+        @Override
+        public String toString() {
+            final StringBuilder builder = new StringBuilder();
+            builder.append("iface=").append(iface);
+            builder.append(" uid=").append(uid);
+            builder.append(" set=").append(setToString(set));
+            builder.append(" tag=").append(tagToString(tag));
+            builder.append(" metered=").append(meteredToString(metered));
+            builder.append(" roaming=").append(roamingToString(roaming));
+            builder.append(" defaultNetwork=").append(defaultNetworkToString(defaultNetwork));
+            builder.append(" rxBytes=").append(rxBytes);
+            builder.append(" rxPackets=").append(rxPackets);
+            builder.append(" txBytes=").append(txBytes);
+            builder.append(" txPackets=").append(txPackets);
+            builder.append(" operations=").append(operations);
+            return builder.toString();
+        }
+
+        /** @hide */
+        @Override
+        public boolean equals(@Nullable Object o) {
+            if (o instanceof Entry) {
+                final Entry e = (Entry) o;
+                return uid == e.uid && set == e.set && tag == e.tag && metered == e.metered
+                        && roaming == e.roaming && defaultNetwork == e.defaultNetwork
+                        && rxBytes == e.rxBytes && rxPackets == e.rxPackets
+                        && txBytes == e.txBytes && txPackets == e.txPackets
+                        && operations == e.operations && TextUtils.equals(iface, e.iface);
+            }
+            return false;
+        }
+
+        /** @hide */
+        @Override
+        public int hashCode() {
+            return Objects.hash(uid, set, tag, metered, roaming, defaultNetwork, iface);
+        }
+    }
+
+    public NetworkStats(long elapsedRealtime, int initialSize) {
+        this.elapsedRealtime = elapsedRealtime;
+        this.size = 0;
+        if (initialSize > 0) {
+            this.capacity = initialSize;
+            this.iface = new String[initialSize];
+            this.uid = new int[initialSize];
+            this.set = new int[initialSize];
+            this.tag = new int[initialSize];
+            this.metered = new int[initialSize];
+            this.roaming = new int[initialSize];
+            this.defaultNetwork = new int[initialSize];
+            this.rxBytes = new long[initialSize];
+            this.rxPackets = new long[initialSize];
+            this.txBytes = new long[initialSize];
+            this.txPackets = new long[initialSize];
+            this.operations = new long[initialSize];
+        } else {
+            // Special case for use by NetworkStatsFactory to start out *really* empty.
+            clear();
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public NetworkStats(Parcel parcel) {
+        elapsedRealtime = parcel.readLong();
+        size = parcel.readInt();
+        capacity = parcel.readInt();
+        iface = parcel.createStringArray();
+        uid = parcel.createIntArray();
+        set = parcel.createIntArray();
+        tag = parcel.createIntArray();
+        metered = parcel.createIntArray();
+        roaming = parcel.createIntArray();
+        defaultNetwork = parcel.createIntArray();
+        rxBytes = parcel.createLongArray();
+        rxPackets = parcel.createLongArray();
+        txBytes = parcel.createLongArray();
+        txPackets = parcel.createLongArray();
+        operations = parcel.createLongArray();
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeLong(elapsedRealtime);
+        dest.writeInt(size);
+        dest.writeInt(capacity);
+        dest.writeStringArray(iface);
+        dest.writeIntArray(uid);
+        dest.writeIntArray(set);
+        dest.writeIntArray(tag);
+        dest.writeIntArray(metered);
+        dest.writeIntArray(roaming);
+        dest.writeIntArray(defaultNetwork);
+        dest.writeLongArray(rxBytes);
+        dest.writeLongArray(rxPackets);
+        dest.writeLongArray(txBytes);
+        dest.writeLongArray(txPackets);
+        dest.writeLongArray(operations);
+    }
+
+    /**
+     * @hide
+     */
+    @Override
+    public NetworkStats clone() {
+        final NetworkStats clone = new NetworkStats(elapsedRealtime, size);
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < size; i++) {
+            entry = getValues(i, entry);
+            clone.insertEntry(entry);
+        }
+        return clone;
+    }
+
+    /**
+     * Clear all data stored in this object.
+     * @hide
+     */
+    public void clear() {
+        this.capacity = 0;
+        this.iface = EmptyArray.STRING;
+        this.uid = EmptyArray.INT;
+        this.set = EmptyArray.INT;
+        this.tag = EmptyArray.INT;
+        this.metered = EmptyArray.INT;
+        this.roaming = EmptyArray.INT;
+        this.defaultNetwork = EmptyArray.INT;
+        this.rxBytes = EmptyArray.LONG;
+        this.rxPackets = EmptyArray.LONG;
+        this.txBytes = EmptyArray.LONG;
+        this.txPackets = EmptyArray.LONG;
+        this.operations = EmptyArray.LONG;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(
+            String iface, long rxBytes, long rxPackets, long txBytes, long txPackets) {
+        return insertEntry(
+                iface, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, rxPackets, txBytes, txPackets, 0L);
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(String iface, int uid, int set, int tag, long rxBytes,
+            long rxPackets, long txBytes, long txPackets, long operations) {
+        return insertEntry(new Entry(
+                iface, uid, set, tag, rxBytes, rxPackets, txBytes, txPackets, operations));
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(String iface, int uid, int set, int tag, int metered,
+            int roaming, int defaultNetwork, long rxBytes, long rxPackets, long txBytes,
+            long txPackets, long operations) {
+        return insertEntry(new Entry(
+                iface, uid, set, tag, metered, roaming, defaultNetwork, rxBytes, rxPackets,
+                txBytes, txPackets, operations));
+    }
+
+    /**
+     * Add new stats entry, copying from given {@link Entry}. The {@link Entry}
+     * object can be recycled across multiple calls.
+     * @hide
+     */
+    public NetworkStats insertEntry(Entry entry) {
+        if (size >= capacity) {
+            final int newLength = Math.max(size, 10) * 3 / 2;
+            iface = Arrays.copyOf(iface, newLength);
+            uid = Arrays.copyOf(uid, newLength);
+            set = Arrays.copyOf(set, newLength);
+            tag = Arrays.copyOf(tag, newLength);
+            metered = Arrays.copyOf(metered, newLength);
+            roaming = Arrays.copyOf(roaming, newLength);
+            defaultNetwork = Arrays.copyOf(defaultNetwork, newLength);
+            rxBytes = Arrays.copyOf(rxBytes, newLength);
+            rxPackets = Arrays.copyOf(rxPackets, newLength);
+            txBytes = Arrays.copyOf(txBytes, newLength);
+            txPackets = Arrays.copyOf(txPackets, newLength);
+            operations = Arrays.copyOf(operations, newLength);
+            capacity = newLength;
+        }
+
+        setValues(size, entry);
+        size++;
+
+        return this;
+    }
+
+    private void setValues(int i, Entry entry) {
+        iface[i] = entry.iface;
+        uid[i] = entry.uid;
+        set[i] = entry.set;
+        tag[i] = entry.tag;
+        metered[i] = entry.metered;
+        roaming[i] = entry.roaming;
+        defaultNetwork[i] = entry.defaultNetwork;
+        rxBytes[i] = entry.rxBytes;
+        rxPackets[i] = entry.rxPackets;
+        txBytes[i] = entry.txBytes;
+        txPackets[i] = entry.txPackets;
+        operations[i] = entry.operations;
+    }
+
+    /**
+     * Iterate over Entry objects.
+     *
+     * Return an iterator of this object that will iterate through all contained Entry objects.
+     *
+     * This iterator does not support concurrent modification and makes no guarantee of fail-fast
+     * behavior. If any method that can mutate the contents of this object is called while
+     * iteration is in progress, either inside the loop or in another thread, then behavior is
+     * undefined.
+     * The remove() method is not implemented and will throw UnsupportedOperationException.
+     * @hide
+     */
+    @SystemApi
+    @NonNull public Iterator<Entry> iterator() {
+        return new Iterator<Entry>() {
+            int mIndex = 0;
+
+            @Override
+            public boolean hasNext() {
+                return mIndex < size;
+            }
+
+            @Override
+            public Entry next() {
+                return getValues(mIndex++, null);
+            }
+        };
+    }
+
+    /**
+     * Return specific stats entry.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(int i, @Nullable Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.iface = iface[i];
+        entry.uid = uid[i];
+        entry.set = set[i];
+        entry.tag = tag[i];
+        entry.metered = metered[i];
+        entry.roaming = roaming[i];
+        entry.defaultNetwork = defaultNetwork[i];
+        entry.rxBytes = rxBytes[i];
+        entry.rxPackets = rxPackets[i];
+        entry.txBytes = txBytes[i];
+        entry.txPackets = txPackets[i];
+        entry.operations = operations[i];
+        return entry;
+    }
+
+    /**
+     * If @{code dest} is not equal to @{code src}, copy entry from index @{code src} to index
+     * @{code dest}.
+     */
+    private void maybeCopyEntry(int dest, int src) {
+        if (dest == src) return;
+        iface[dest] = iface[src];
+        uid[dest] = uid[src];
+        set[dest] = set[src];
+        tag[dest] = tag[src];
+        metered[dest] = metered[src];
+        roaming[dest] = roaming[src];
+        defaultNetwork[dest] = defaultNetwork[src];
+        rxBytes[dest] = rxBytes[src];
+        rxPackets[dest] = rxPackets[src];
+        txBytes[dest] = txBytes[src];
+        txPackets[dest] = txPackets[src];
+        operations[dest] = operations[src];
+    }
+
+    /** @hide */
+    public long getElapsedRealtime() {
+        return elapsedRealtime;
+    }
+
+    /** @hide */
+    public void setElapsedRealtime(long time) {
+        elapsedRealtime = time;
+    }
+
+    /**
+     * Return age of this {@link NetworkStats} object with respect to
+     * {@link SystemClock#elapsedRealtime()}.
+     * @hide
+     */
+    public long getElapsedRealtimeAge() {
+        return SystemClock.elapsedRealtime() - elapsedRealtime;
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public int size() {
+        return size;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public int internalSize() {
+        return capacity;
+    }
+
+    /** @hide */
+    @Deprecated
+    public NetworkStats combineValues(String iface, int uid, int tag, long rxBytes, long rxPackets,
+            long txBytes, long txPackets, long operations) {
+        return combineValues(
+                iface, uid, SET_DEFAULT, tag, rxBytes, rxPackets, txBytes,
+                txPackets, operations);
+    }
+
+    /** @hide */
+    public NetworkStats combineValues(String iface, int uid, int set, int tag,
+            long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+        return combineValues(new Entry(
+                iface, uid, set, tag, rxBytes, rxPackets, txBytes, txPackets, operations));
+    }
+
+    /**
+     * Combine given values with an existing row, or create a new row if
+     * {@link #findIndex(String, int, int, int, int, int, int)} is unable to find match. Can
+     * also be used to subtract values from existing rows. This method mutates the referencing
+     * {@link NetworkStats} object.
+     *
+     * @param entry the {@link Entry} to combine.
+     * @return a reference to this mutated {@link NetworkStats} object.
+     * @hide
+     */
+    public @NonNull NetworkStats combineValues(@NonNull Entry entry) {
+        final int i = findIndex(entry.iface, entry.uid, entry.set, entry.tag, entry.metered,
+                entry.roaming, entry.defaultNetwork);
+        if (i == -1) {
+            // only create new entry when positive contribution
+            insertEntry(entry);
+        } else {
+            rxBytes[i] += entry.rxBytes;
+            rxPackets[i] += entry.rxPackets;
+            txBytes[i] += entry.txBytes;
+            txPackets[i] += entry.txPackets;
+            operations[i] += entry.operations;
+        }
+        return this;
+    }
+
+    /**
+     * Add given values with an existing row, or create a new row if
+     * {@link #findIndex(String, int, int, int, int, int, int)} is unable to find match. Can
+     * also be used to subtract values from existing rows.
+     *
+     * @param entry the {@link Entry} to add.
+     * @return a new constructed {@link NetworkStats} object that contains the result.
+     */
+    public @NonNull NetworkStats addEntry(@NonNull Entry entry) {
+        return this.clone().combineValues(entry);
+    }
+
+    /**
+     * Add the given {@link NetworkStats} objects.
+     *
+     * @return the sum of two objects.
+     */
+    public @NonNull NetworkStats add(@NonNull NetworkStats another) {
+        final NetworkStats ret = this.clone();
+        ret.combineAllValues(another);
+        return ret;
+    }
+
+    /**
+     * Combine all values from another {@link NetworkStats} into this object.
+     * @hide
+     */
+    public void combineAllValues(@NonNull NetworkStats another) {
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < another.size; i++) {
+            entry = another.getValues(i, entry);
+            combineValues(entry);
+        }
+    }
+
+    /**
+     * Find first stats index that matches the requested parameters.
+     * @hide
+     */
+    public int findIndex(String iface, int uid, int set, int tag, int metered, int roaming,
+            int defaultNetwork) {
+        for (int i = 0; i < size; i++) {
+            if (uid == this.uid[i] && set == this.set[i] && tag == this.tag[i]
+                    && metered == this.metered[i] && roaming == this.roaming[i]
+                    && defaultNetwork == this.defaultNetwork[i]
+                    && Objects.equals(iface, this.iface[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    /**
+     * Find first stats index that matches the requested parameters, starting
+     * search around the hinted index as an optimization.
+     * @hide
+     */
+    @VisibleForTesting
+    public int findIndexHinted(String iface, int uid, int set, int tag, int metered, int roaming,
+            int defaultNetwork, int hintIndex) {
+        for (int offset = 0; offset < size; offset++) {
+            final int halfOffset = offset / 2;
+
+            // search outwards from hint index, alternating forward and backward
+            final int i;
+            if (offset % 2 == 0) {
+                i = (hintIndex + halfOffset) % size;
+            } else {
+                i = (size + hintIndex - halfOffset - 1) % size;
+            }
+
+            if (uid == this.uid[i] && set == this.set[i] && tag == this.tag[i]
+                    && metered == this.metered[i] && roaming == this.roaming[i]
+                    && defaultNetwork == this.defaultNetwork[i]
+                    && Objects.equals(iface, this.iface[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    /**
+     * Splice in {@link #operations} from the given {@link NetworkStats} based
+     * on matching {@link #uid} and {@link #tag} rows. Ignores {@link #iface},
+     * since operation counts are at data layer.
+     * @hide
+     */
+    public void spliceOperationsFrom(NetworkStats stats) {
+        for (int i = 0; i < size; i++) {
+            final int j = stats.findIndex(iface[i], uid[i], set[i], tag[i], metered[i], roaming[i],
+                    defaultNetwork[i]);
+            if (j == -1) {
+                operations[i] = 0;
+            } else {
+                operations[i] = stats.operations[j];
+            }
+        }
+    }
+
+    /**
+     * Return list of unique interfaces known by this data structure.
+     * @hide
+     */
+    public String[] getUniqueIfaces() {
+        final HashSet<String> ifaces = new HashSet<String>();
+        for (String iface : this.iface) {
+            if (iface != IFACE_ALL) {
+                ifaces.add(iface);
+            }
+        }
+        return ifaces.toArray(new String[ifaces.size()]);
+    }
+
+    /**
+     * Return list of unique UIDs known by this data structure.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public int[] getUniqueUids() {
+        final SparseBooleanArray uids = new SparseBooleanArray();
+        for (int uid : this.uid) {
+            uids.put(uid, true);
+        }
+
+        final int size = uids.size();
+        final int[] result = new int[size];
+        for (int i = 0; i < size; i++) {
+            result[i] = uids.keyAt(i);
+        }
+        return result;
+    }
+
+    /**
+     * Return total bytes represented by this snapshot object, usually used when
+     * checking if a {@link #subtract(NetworkStats)} delta passes a threshold.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public long getTotalBytes() {
+        final Entry entry = getTotal(null);
+        return entry.rxBytes + entry.txBytes;
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getTotal(Entry recycle) {
+        return getTotal(recycle, null, UID_ALL, false);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #uid}.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getTotal(Entry recycle, int limitUid) {
+        return getTotal(recycle, null, limitUid, false);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #iface}.
+     * @hide
+     */
+    public Entry getTotal(Entry recycle, HashSet<String> limitIface) {
+        return getTotal(recycle, limitIface, UID_ALL, false);
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public Entry getTotalIncludingTags(Entry recycle) {
+        return getTotal(recycle, null, UID_ALL, true);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #iface} and {@link #uid}.
+     *
+     * @param limitIface Set of {@link #iface} to include in total; or {@code
+     *            null} to include all ifaces.
+     */
+    private Entry getTotal(
+            Entry recycle, HashSet<String> limitIface, int limitUid, boolean includeTags) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+
+        entry.iface = IFACE_ALL;
+        entry.uid = limitUid;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+        entry.rxBytes = 0;
+        entry.rxPackets = 0;
+        entry.txBytes = 0;
+        entry.txPackets = 0;
+        entry.operations = 0;
+
+        for (int i = 0; i < size; i++) {
+            final boolean matchesUid = (limitUid == UID_ALL) || (limitUid == uid[i]);
+            final boolean matchesIface = (limitIface == null) || (limitIface.contains(iface[i]));
+
+            if (matchesUid && matchesIface) {
+                // skip specific tags, since already counted in TAG_NONE
+                if (tag[i] != TAG_NONE && !includeTags) continue;
+
+                entry.rxBytes += rxBytes[i];
+                entry.rxPackets += rxPackets[i];
+                entry.txBytes += txBytes[i];
+                entry.txPackets += txPackets[i];
+                entry.operations += operations[i];
+            }
+        }
+        return entry;
+    }
+
+    /**
+     * Fast path for battery stats.
+     * @hide
+     */
+    public long getTotalPackets() {
+        long total = 0;
+        for (int i = size-1; i >= 0; i--) {
+            total += rxPackets[i] + txPackets[i];
+        }
+        return total;
+    }
+
+    /**
+     * Subtract the given {@link NetworkStats}, effectively leaving the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared. This method does not mutate
+     * the referencing object.
+     *
+     * @return the delta between two objects.
+     */
+    public @NonNull NetworkStats subtract(@NonNull NetworkStats right) {
+        return subtract(this, right, null, null);
+    }
+
+    /**
+     * Subtract the two given {@link NetworkStats} objects, returning the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared.
+     * <p>
+     * If counters have rolled backwards, they are clamped to {@code 0} and
+     * reported to the given {@link NonMonotonicObserver}.
+     * @hide
+     */
+    public static <C> NetworkStats subtract(NetworkStats left, NetworkStats right,
+            NonMonotonicObserver<C> observer, C cookie) {
+        return subtract(left, right, observer, cookie, null);
+    }
+
+    /**
+     * Subtract the two given {@link NetworkStats} objects, returning the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared.
+     * <p>
+     * If counters have rolled backwards, they are clamped to {@code 0} and
+     * reported to the given {@link NonMonotonicObserver}.
+     * <p>
+     * If <var>recycle</var> is supplied, this NetworkStats object will be
+     * reused (and returned) as the result if it is large enough to contain
+     * the data.
+     * @hide
+     */
+    public static <C> NetworkStats subtract(NetworkStats left, NetworkStats right,
+            NonMonotonicObserver<C> observer, C cookie, NetworkStats recycle) {
+        long deltaRealtime = left.elapsedRealtime - right.elapsedRealtime;
+        if (deltaRealtime < 0) {
+            if (observer != null) {
+                observer.foundNonMonotonic(left, -1, right, -1, cookie);
+            }
+            deltaRealtime = 0;
+        }
+
+        // result will have our rows, and elapsed time between snapshots
+        final Entry entry = new Entry();
+        final NetworkStats result;
+        if (recycle != null && recycle.capacity >= left.size) {
+            result = recycle;
+            result.size = 0;
+            result.elapsedRealtime = deltaRealtime;
+        } else {
+            result = new NetworkStats(deltaRealtime, left.size);
+        }
+        for (int i = 0; i < left.size; i++) {
+            entry.iface = left.iface[i];
+            entry.uid = left.uid[i];
+            entry.set = left.set[i];
+            entry.tag = left.tag[i];
+            entry.metered = left.metered[i];
+            entry.roaming = left.roaming[i];
+            entry.defaultNetwork = left.defaultNetwork[i];
+            entry.rxBytes = left.rxBytes[i];
+            entry.rxPackets = left.rxPackets[i];
+            entry.txBytes = left.txBytes[i];
+            entry.txPackets = left.txPackets[i];
+            entry.operations = left.operations[i];
+
+            // find remote row that matches, and subtract
+            final int j = right.findIndexHinted(entry.iface, entry.uid, entry.set, entry.tag,
+                    entry.metered, entry.roaming, entry.defaultNetwork, i);
+            if (j != -1) {
+                // Found matching row, subtract remote value.
+                entry.rxBytes -= right.rxBytes[j];
+                entry.rxPackets -= right.rxPackets[j];
+                entry.txBytes -= right.txBytes[j];
+                entry.txPackets -= right.txPackets[j];
+                entry.operations -= right.operations[j];
+            }
+
+            if (entry.isNegative()) {
+                if (observer != null) {
+                    observer.foundNonMonotonic(left, i, right, j, cookie);
+                }
+                entry.rxBytes = Math.max(entry.rxBytes, 0);
+                entry.rxPackets = Math.max(entry.rxPackets, 0);
+                entry.txBytes = Math.max(entry.txBytes, 0);
+                entry.txPackets = Math.max(entry.txPackets, 0);
+                entry.operations = Math.max(entry.operations, 0);
+            }
+
+            result.insertEntry(entry);
+        }
+
+        return result;
+    }
+
+    /**
+     * Calculate and apply adjustments to captured statistics for 464xlat traffic.
+     *
+     * <p>This mutates stacked traffic stats, to account for IPv4/IPv6 header size difference.
+     *
+     * <p>UID stats, which are only accounted on the stacked interface, need to be increased
+     * by 20 bytes/packet to account for translation overhead.
+     *
+     * <p>The potential additional overhead of 8 bytes/packet for ip fragments is ignored.
+     *
+     * <p>Interface stats need to sum traffic on both stacked and base interface because:
+     *   - eBPF offloaded packets appear only on the stacked interface
+     *   - Non-offloaded ingress packets appear only on the stacked interface
+     *     (due to iptables raw PREROUTING drop rules)
+     *   - Non-offloaded egress packets appear only on the stacked interface
+     *     (due to ignoring traffic from clat daemon by uid match)
+     * (and of course the 20 bytes/packet overhead needs to be applied to stacked interface stats)
+     *
+     * <p>This method will behave fine if {@code stackedIfaces} is an non-synchronized but add-only
+     * {@code ConcurrentHashMap}
+     * @param baseTraffic Traffic on the base interfaces. Will be mutated.
+     * @param stackedTraffic Stats with traffic stacked on top of our ifaces. Will also be mutated.
+     * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both.
+     * @hide
+     */
+    public static void apply464xlatAdjustments(NetworkStats baseTraffic,
+            NetworkStats stackedTraffic, Map<String, String> stackedIfaces) {
+        // For recycling
+        Entry entry = null;
+        for (int i = 0; i < stackedTraffic.size; i++) {
+            entry = stackedTraffic.getValues(i, entry);
+            if (entry == null) continue;
+            if (entry.iface == null) continue;
+            if (!entry.iface.startsWith(CLATD_INTERFACE_PREFIX)) continue;
+
+            // For 464xlat traffic, per uid stats only counts the bytes of the native IPv4 packet
+            // sent on the stacked interface with prefix "v4-" and drops the IPv6 header size after
+            // unwrapping. To account correctly for on-the-wire traffic, add the 20 additional bytes
+            // difference for all packets (http://b/12249687, http:/b/33681750).
+            //
+            // Note: this doesn't account for LRO/GRO/GSO/TSO (ie. >mtu) traffic correctly, nor
+            // does it correctly account for the 8 extra bytes in the IPv6 fragmentation header.
+            //
+            // While the ebpf code path does try to simulate proper post segmentation packet
+            // counts, we have nothing of the sort of xt_qtaguid stats.
+            entry.rxBytes += entry.rxPackets * IPV4V6_HEADER_DELTA;
+            entry.txBytes += entry.txPackets * IPV4V6_HEADER_DELTA;
+            stackedTraffic.setValues(i, entry);
+        }
+    }
+
+    /**
+     * Calculate and apply adjustments to captured statistics for 464xlat traffic counted twice.
+     *
+     * <p>This mutates the object this method is called on. Equivalent to calling
+     * {@link #apply464xlatAdjustments(NetworkStats, NetworkStats, Map)} with {@code this} as
+     * base and stacked traffic.
+     * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both.
+     * @hide
+     */
+    public void apply464xlatAdjustments(Map<String, String> stackedIfaces) {
+        apply464xlatAdjustments(this, this, stackedIfaces);
+    }
+
+    /**
+     * Return total statistics grouped by {@link #iface}; doesn't mutate the
+     * original structure.
+     * @hide
+     */
+    public NetworkStats groupedByIface() {
+        final NetworkStats stats = new NetworkStats(elapsedRealtime, 10);
+
+        final Entry entry = new Entry();
+        entry.uid = UID_ALL;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+        entry.operations = 0L;
+
+        for (int i = 0; i < size; i++) {
+            // skip specific tags, since already counted in TAG_NONE
+            if (tag[i] != TAG_NONE) continue;
+
+            entry.iface = iface[i];
+            entry.rxBytes = rxBytes[i];
+            entry.rxPackets = rxPackets[i];
+            entry.txBytes = txBytes[i];
+            entry.txPackets = txPackets[i];
+            stats.combineValues(entry);
+        }
+
+        return stats;
+    }
+
+    /**
+     * Return total statistics grouped by {@link #uid}; doesn't mutate the
+     * original structure.
+     * @hide
+     */
+    public NetworkStats groupedByUid() {
+        final NetworkStats stats = new NetworkStats(elapsedRealtime, 10);
+
+        final Entry entry = new Entry();
+        entry.iface = IFACE_ALL;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+
+        for (int i = 0; i < size; i++) {
+            // skip specific tags, since already counted in TAG_NONE
+            if (tag[i] != TAG_NONE) continue;
+
+            entry.uid = uid[i];
+            entry.rxBytes = rxBytes[i];
+            entry.rxPackets = rxPackets[i];
+            entry.txBytes = txBytes[i];
+            entry.txPackets = txPackets[i];
+            entry.operations = operations[i];
+            stats.combineValues(entry);
+        }
+
+        return stats;
+    }
+
+    /**
+     * Remove all rows that match one of specified UIDs.
+     * This mutates the original structure in place.
+     * @hide
+     */
+    public void removeUids(int[] uids) {
+        filter(e -> !CollectionUtils.contains(uids, e.uid));
+    }
+
+    /**
+     * Remove all rows that match one of specified UIDs.
+     * @return the result object.
+     * @hide
+     */
+    @NonNull
+    public NetworkStats removeEmptyEntries() {
+        final NetworkStats ret = this.clone();
+        ret.filter(e -> e.rxBytes != 0 || e.rxPackets != 0 || e.txBytes != 0 || e.txPackets != 0
+                || e.operations != 0);
+        return ret;
+    }
+
+    /**
+     * Only keep entries that match all specified filters.
+     *
+     * <p>This mutates the original structure in place. After this method is called,
+     * size is the number of matching entries, and capacity is the previous capacity.
+     * @param limitUid UID to filter for, or {@link #UID_ALL}.
+     * @param limitIfaces Interfaces to filter for, or {@link #INTERFACES_ALL}.
+     * @param limitTag Tag to filter for, or {@link #TAG_ALL}.
+     * @hide
+     */
+    public void filter(int limitUid, String[] limitIfaces, int limitTag) {
+        if (limitUid == UID_ALL && limitTag == TAG_ALL && limitIfaces == INTERFACES_ALL) {
+            return;
+        }
+        filter(e -> (limitUid == UID_ALL || limitUid == e.uid)
+                && (limitTag == TAG_ALL || limitTag == e.tag)
+                && (limitIfaces == INTERFACES_ALL
+                    || CollectionUtils.contains(limitIfaces, e.iface)));
+    }
+
+    /**
+     * Only keep entries with {@link #set} value less than {@link #SET_DEBUG_START}.
+     *
+     * <p>This mutates the original structure in place.
+     * @hide
+     */
+    public void filterDebugEntries() {
+        filter(e -> e.set < SET_DEBUG_START);
+    }
+
+    private void filter(Predicate<Entry> predicate) {
+        Entry entry = new Entry();
+        int nextOutputEntry = 0;
+        for (int i = 0; i < size; i++) {
+            entry = getValues(i, entry);
+            if (predicate.test(entry)) {
+                if (nextOutputEntry != i) {
+                    setValues(nextOutputEntry, entry);
+                }
+                nextOutputEntry++;
+            }
+        }
+        size = nextOutputEntry;
+    }
+
+    /** @hide */
+    public void dump(String prefix, PrintWriter pw) {
+        pw.print(prefix);
+        pw.print("NetworkStats: elapsedRealtime="); pw.println(elapsedRealtime);
+        for (int i = 0; i < size; i++) {
+            pw.print(prefix);
+            pw.print("  ["); pw.print(i); pw.print("]");
+            pw.print(" iface="); pw.print(iface[i]);
+            pw.print(" uid="); pw.print(uid[i]);
+            pw.print(" set="); pw.print(setToString(set[i]));
+            pw.print(" tag="); pw.print(tagToString(tag[i]));
+            pw.print(" metered="); pw.print(meteredToString(metered[i]));
+            pw.print(" roaming="); pw.print(roamingToString(roaming[i]));
+            pw.print(" defaultNetwork="); pw.print(defaultNetworkToString(defaultNetwork[i]));
+            pw.print(" rxBytes="); pw.print(rxBytes[i]);
+            pw.print(" rxPackets="); pw.print(rxPackets[i]);
+            pw.print(" txBytes="); pw.print(txBytes[i]);
+            pw.print(" txPackets="); pw.print(txPackets[i]);
+            pw.print(" operations="); pw.println(operations[i]);
+        }
+    }
+
+    /**
+     * Return text description of {@link #set} value.
+     * @hide
+     */
+    public static String setToString(int set) {
+        switch (set) {
+            case SET_ALL:
+                return "ALL";
+            case SET_DEFAULT:
+                return "DEFAULT";
+            case SET_FOREGROUND:
+                return "FOREGROUND";
+            case SET_DBG_VPN_IN:
+                return "DBG_VPN_IN";
+            case SET_DBG_VPN_OUT:
+                return "DBG_VPN_OUT";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #set} value.
+     * @hide
+     */
+    public static String setToCheckinString(int set) {
+        switch (set) {
+            case SET_ALL:
+                return "all";
+            case SET_DEFAULT:
+                return "def";
+            case SET_FOREGROUND:
+                return "fg";
+            case SET_DBG_VPN_IN:
+                return "vpnin";
+            case SET_DBG_VPN_OUT:
+                return "vpnout";
+            default:
+                return "unk";
+        }
+    }
+
+    /**
+     * @return true if the querySet matches the dataSet.
+     * @hide
+     */
+    public static boolean setMatches(int querySet, int dataSet) {
+        if (querySet == dataSet) {
+            return true;
+        }
+        // SET_ALL matches all non-debugging sets.
+        return querySet == SET_ALL && dataSet < SET_DEBUG_START;
+    }
+
+    /**
+     * Return text description of {@link #tag} value.
+     * @hide
+     */
+    public static String tagToString(int tag) {
+        return "0x" + Integer.toHexString(tag);
+    }
+
+    /**
+     * Return text description of {@link #metered} value.
+     * @hide
+     */
+    public static String meteredToString(int metered) {
+        switch (metered) {
+            case METERED_ALL:
+                return "ALL";
+            case METERED_NO:
+                return "NO";
+            case METERED_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #roaming} value.
+     * @hide
+     */
+    public static String roamingToString(int roaming) {
+        switch (roaming) {
+            case ROAMING_ALL:
+                return "ALL";
+            case ROAMING_NO:
+                return "NO";
+            case ROAMING_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #defaultNetwork} value.
+     * @hide
+     */
+    public static String defaultNetworkToString(int defaultNetwork) {
+        switch (defaultNetwork) {
+            case DEFAULT_NETWORK_ALL:
+                return "ALL";
+            case DEFAULT_NETWORK_NO:
+                return "NO";
+            case DEFAULT_NETWORK_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /** @hide */
+    @Override
+    public String toString() {
+        final CharArrayWriter writer = new CharArrayWriter();
+        dump("", new PrintWriter(writer));
+        return writer.toString();
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    public static final @NonNull Creator<NetworkStats> CREATOR = new Creator<NetworkStats>() {
+        @Override
+        public NetworkStats createFromParcel(Parcel in) {
+            return new NetworkStats(in);
+        }
+
+        @Override
+        public NetworkStats[] newArray(int size) {
+            return new NetworkStats[size];
+        }
+    };
+
+    /** @hide */
+    public interface NonMonotonicObserver<C> {
+        public void foundNonMonotonic(
+                NetworkStats left, int leftIndex, NetworkStats right, int rightIndex, C cookie);
+        public void foundNonMonotonic(
+                NetworkStats stats, int statsIndex, C cookie);
+    }
+
+    /**
+     * VPN accounting. Move some VPN's underlying traffic to other UIDs that use tun0 iface.
+     *
+     * <p>This method should only be called on delta NetworkStats. Do not call this method on a
+     * snapshot {@link NetworkStats} object because the tunUid and/or the underlyingIface may change
+     * over time.
+     *
+     * <p>This method performs adjustments for one active VPN package and one VPN iface at a time.
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @hide
+     */
+    public void migrateTun(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces) {
+        // Combined usage by all apps using VPN.
+        final Entry tunIfaceTotal = new Entry();
+        // Usage by VPN, grouped by its {@code underlyingIfaces}.
+        final Entry[] perInterfaceTotal = new Entry[underlyingIfaces.size()];
+        // Usage by VPN, summed across all its {@code underlyingIfaces}.
+        final Entry underlyingIfacesTotal = new Entry();
+
+        for (int i = 0; i < perInterfaceTotal.length; i++) {
+            perInterfaceTotal[i] = new Entry();
+        }
+
+        tunAdjustmentInit(tunUid, tunIface, underlyingIfaces, tunIfaceTotal, perInterfaceTotal,
+                underlyingIfacesTotal);
+
+        // If tunIface < underlyingIfacesTotal, it leaves the overhead traffic in the VPN app.
+        // If tunIface > underlyingIfacesTotal, the VPN app doesn't get credit for data compression.
+        // Negative stats should be avoided.
+        final Entry[] moved =
+                addTrafficToApplications(tunUid, tunIface, underlyingIfaces, tunIfaceTotal,
+                        perInterfaceTotal, underlyingIfacesTotal);
+        deductTrafficFromVpnApp(tunUid, underlyingIfaces, moved);
+    }
+
+    /**
+     * Initializes the data used by the migrateTun() method.
+     *
+     * <p>This is the first pass iteration which does the following work:
+     *
+     * <ul>
+     *   <li>Adds up all the traffic through the tunUid's underlyingIfaces (both foreground and
+     *       background).
+     *   <li>Adds up all the traffic through tun0 excluding traffic from the vpn app itself.
+     * </ul>
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @param tunIfaceTotal output parameter; combined data usage by all apps using VPN
+     * @param perInterfaceTotal output parameter; data usage by VPN app, grouped by its {@code
+     *     underlyingIfaces}
+     * @param underlyingIfacesTotal output parameter; data usage by VPN, summed across all of its
+     *     {@code underlyingIfaces}
+     */
+    private void tunAdjustmentInit(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces, @NonNull Entry tunIfaceTotal,
+            @NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
+        final Entry recycle = new Entry();
+        for (int i = 0; i < size; i++) {
+            getValues(i, recycle);
+            if (recycle.uid == UID_ALL) {
+                throw new IllegalStateException(
+                        "Cannot adjust VPN accounting on an iface aggregated NetworkStats.");
+            }
+            if (recycle.set == SET_DBG_VPN_IN || recycle.set == SET_DBG_VPN_OUT) {
+                throw new IllegalStateException(
+                        "Cannot adjust VPN accounting on a NetworkStats containing SET_DBG_VPN_*");
+            }
+            if (recycle.tag != TAG_NONE) {
+                // TODO(b/123666283): Take all tags for tunUid into account.
+                continue;
+            }
+
+            if (tunUid == Process.SYSTEM_UID) {
+                // Kernel-based VPN or VCN, traffic sent by apps on the VPN/VCN network
+                //
+                // Since the data is not UID-accounted on underlying networks, just use VPN/VCN
+                // network usage as ground truth. Encrypted traffic on the underlying networks will
+                // never be processed here because encrypted traffic on the underlying interfaces
+                // is not present in UID stats, and this method is only called on UID stats.
+                if (tunIface.equals(recycle.iface)) {
+                    tunIfaceTotal.add(recycle);
+                    underlyingIfacesTotal.add(recycle);
+
+                    // In steady state, there should always be one network, but edge cases may
+                    // result in the network being null (network lost), and thus no underlying
+                    // ifaces is possible.
+                    if (perInterfaceTotal.length > 0) {
+                        // While platform VPNs and VCNs have exactly one underlying network, that
+                        // network may have multiple interfaces (eg for 464xlat). This layer does
+                        // not have the required information to identify which of the interfaces
+                        // were used. Select "any" of the interfaces. Since overhead is already
+                        // lost, this number is an approximation anyways.
+                        perInterfaceTotal[0].add(recycle);
+                    }
+                }
+            } else if (recycle.uid == tunUid) {
+                // VpnService VPN, traffic sent by the VPN app over underlying networks
+                for (int j = 0; j < underlyingIfaces.size(); j++) {
+                    if (Objects.equals(underlyingIfaces.get(j), recycle.iface)) {
+                        perInterfaceTotal[j].add(recycle);
+                        underlyingIfacesTotal.add(recycle);
+                        break;
+                    }
+                }
+            } else if (tunIface.equals(recycle.iface)) {
+                // VpnService VPN; traffic sent by apps on the VPN network
+                tunIfaceTotal.add(recycle);
+            }
+        }
+    }
+
+    /**
+     * Distributes traffic across apps that are using given {@code tunIface}, and returns the total
+     * traffic that should be moved off of {@code tunUid} grouped by {@code underlyingIfaces}.
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @param tunIfaceTotal combined data usage across all apps using {@code tunIface}
+     * @param perInterfaceTotal data usage by VPN app, grouped by its {@code underlyingIfaces}
+     * @param underlyingIfacesTotal data usage by VPN, summed across all of its {@code
+     *     underlyingIfaces}
+     */
+    private Entry[] addTrafficToApplications(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces, @NonNull Entry tunIfaceTotal,
+            @NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
+        // Traffic that should be moved off of each underlying interface for tunUid (see
+        // deductTrafficFromVpnApp below).
+        final Entry[] moved = new Entry[underlyingIfaces.size()];
+        for (int i = 0; i < underlyingIfaces.size(); i++) {
+            moved[i] = new Entry();
+        }
+
+        final Entry tmpEntry = new Entry();
+        final int origSize = size;
+        for (int i = 0; i < origSize; i++) {
+            if (!Objects.equals(iface[i], tunIface)) {
+                // Consider only entries that go onto the VPN interface.
+                continue;
+            }
+
+            if (uid[i] == tunUid && tunUid != Process.SYSTEM_UID) {
+                // Exclude VPN app from the redistribution, as it can choose to create packet
+                // streams by writing to itself.
+                //
+                // However, for platform VPNs, do not exclude the system's usage of the VPN network,
+                // since it is never local-only, and never double counted
+                continue;
+            }
+            tmpEntry.uid = uid[i];
+            tmpEntry.tag = tag[i];
+            tmpEntry.metered = metered[i];
+            tmpEntry.roaming = roaming[i];
+            tmpEntry.defaultNetwork = defaultNetwork[i];
+
+            // In a first pass, compute this entry's total share of data across all
+            // underlyingIfaces. This is computed on the basis of the share of this entry's usage
+            // over tunIface.
+            // TODO: Consider refactoring first pass into a separate helper method.
+            long totalRxBytes = 0;
+            if (tunIfaceTotal.rxBytes > 0) {
+                // Note - The multiplication below should not overflow since NetworkStatsService
+                // processes this every time device has transmitted/received amount equivalent to
+                // global threshold alert (~ 2MB) across all interfaces.
+                final long rxBytesAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.rxBytes,
+                                rxBytes[i], tunIfaceTotal.rxBytes);
+                // app must not be blamed for more than it consumed on tunIface
+                totalRxBytes = Math.min(rxBytes[i], rxBytesAcrossUnderlyingIfaces);
+            }
+            long totalRxPackets = 0;
+            if (tunIfaceTotal.rxPackets > 0) {
+                final long rxPacketsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.rxPackets,
+                                rxPackets[i], tunIfaceTotal.rxPackets);
+                totalRxPackets = Math.min(rxPackets[i], rxPacketsAcrossUnderlyingIfaces);
+            }
+            long totalTxBytes = 0;
+            if (tunIfaceTotal.txBytes > 0) {
+                final long txBytesAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.txBytes,
+                                txBytes[i], tunIfaceTotal.txBytes);
+                totalTxBytes = Math.min(txBytes[i], txBytesAcrossUnderlyingIfaces);
+            }
+            long totalTxPackets = 0;
+            if (tunIfaceTotal.txPackets > 0) {
+                final long txPacketsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.txPackets,
+                                txPackets[i], tunIfaceTotal.txPackets);
+                totalTxPackets = Math.min(txPackets[i], txPacketsAcrossUnderlyingIfaces);
+            }
+            long totalOperations = 0;
+            if (tunIfaceTotal.operations > 0) {
+                final long operationsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.operations,
+                                operations[i], tunIfaceTotal.operations);
+                totalOperations = Math.min(operations[i], operationsAcrossUnderlyingIfaces);
+            }
+            // In a second pass, distribute these values across interfaces in the proportion that
+            // each interface represents of the total traffic of the underlying interfaces.
+            for (int j = 0; j < underlyingIfaces.size(); j++) {
+                tmpEntry.iface = underlyingIfaces.get(j);
+                tmpEntry.rxBytes = 0;
+                // Reset 'set' to correct value since it gets updated when adding debug info below.
+                tmpEntry.set = set[i];
+                if (underlyingIfacesTotal.rxBytes > 0) {
+                    tmpEntry.rxBytes =
+                            multiplySafeByRational(totalRxBytes,
+                                    perInterfaceTotal[j].rxBytes,
+                                    underlyingIfacesTotal.rxBytes);
+                }
+                tmpEntry.rxPackets = 0;
+                if (underlyingIfacesTotal.rxPackets > 0) {
+                    tmpEntry.rxPackets =
+                            multiplySafeByRational(totalRxPackets,
+                                    perInterfaceTotal[j].rxPackets,
+                                    underlyingIfacesTotal.rxPackets);
+                }
+                tmpEntry.txBytes = 0;
+                if (underlyingIfacesTotal.txBytes > 0) {
+                    tmpEntry.txBytes =
+                            multiplySafeByRational(totalTxBytes,
+                                    perInterfaceTotal[j].txBytes,
+                                    underlyingIfacesTotal.txBytes);
+                }
+                tmpEntry.txPackets = 0;
+                if (underlyingIfacesTotal.txPackets > 0) {
+                    tmpEntry.txPackets =
+                            multiplySafeByRational(totalTxPackets,
+                                    perInterfaceTotal[j].txPackets,
+                                    underlyingIfacesTotal.txPackets);
+                }
+                tmpEntry.operations = 0;
+                if (underlyingIfacesTotal.operations > 0) {
+                    tmpEntry.operations =
+                            multiplySafeByRational(totalOperations,
+                                    perInterfaceTotal[j].operations,
+                                    underlyingIfacesTotal.operations);
+                }
+                // tmpEntry now contains the migrated data of the i-th entry for the j-th underlying
+                // interface. Add that data usage to this object.
+                combineValues(tmpEntry);
+                if (tag[i] == TAG_NONE) {
+                    // Add the migrated data to moved so it is deducted from the VPN app later.
+                    moved[j].add(tmpEntry);
+                    // Add debug info
+                    tmpEntry.set = SET_DBG_VPN_IN;
+                    combineValues(tmpEntry);
+                }
+            }
+        }
+        return moved;
+    }
+
+    private void deductTrafficFromVpnApp(
+            int tunUid,
+            @NonNull List<String> underlyingIfaces,
+            @NonNull Entry[] moved) {
+        if (tunUid == Process.SYSTEM_UID) {
+            // No traffic recorded on a per-UID basis for in-kernel VPN/VCNs over underlying
+            // networks; thus no traffic to deduct.
+            return;
+        }
+
+        for (int i = 0; i < underlyingIfaces.size(); i++) {
+            moved[i].uid = tunUid;
+            // Add debug info
+            moved[i].set = SET_DBG_VPN_OUT;
+            moved[i].tag = TAG_NONE;
+            moved[i].iface = underlyingIfaces.get(i);
+            moved[i].metered = METERED_ALL;
+            moved[i].roaming = ROAMING_ALL;
+            moved[i].defaultNetwork = DEFAULT_NETWORK_ALL;
+            combineValues(moved[i]);
+
+            // Caveat: if the vpn software uses tag, the total tagged traffic may be greater than
+            // the TAG_NONE traffic.
+            //
+            // Relies on the fact that the underlying traffic only has state ROAMING_NO and
+            // METERED_NO, which should be the case as it comes directly from the /proc file.
+            // We only blend in the roaming data after applying these adjustments, by checking the
+            // NetworkIdentity of the underlying iface.
+            final int idxVpnBackground = findIndex(underlyingIfaces.get(i), tunUid, SET_DEFAULT,
+                            TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
+            if (idxVpnBackground != -1) {
+                // Note - tunSubtract also updates moved[i]; whatever traffic that's left is removed
+                // from foreground usage.
+                tunSubtract(idxVpnBackground, this, moved[i]);
+            }
+
+            final int idxVpnForeground = findIndex(underlyingIfaces.get(i), tunUid, SET_FOREGROUND,
+                            TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
+            if (idxVpnForeground != -1) {
+                tunSubtract(idxVpnForeground, this, moved[i]);
+            }
+        }
+    }
+
+    private static void tunSubtract(int i, @NonNull NetworkStats left, @NonNull Entry right) {
+        long rxBytes = Math.min(left.rxBytes[i], right.rxBytes);
+        left.rxBytes[i] -= rxBytes;
+        right.rxBytes -= rxBytes;
+
+        long rxPackets = Math.min(left.rxPackets[i], right.rxPackets);
+        left.rxPackets[i] -= rxPackets;
+        right.rxPackets -= rxPackets;
+
+        long txBytes = Math.min(left.txBytes[i], right.txBytes);
+        left.txBytes[i] -= txBytes;
+        right.txBytes -= txBytes;
+
+        long txPackets = Math.min(left.txPackets[i], right.txPackets);
+        left.txPackets[i] -= txPackets;
+        right.txPackets -= txPackets;
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStatsAccess.java b/framework-t/src/android/net/NetworkStatsAccess.java
new file mode 100644
index 0000000..b64fbdb
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsAccess.java
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.Manifest.permission.READ_NETWORK_USAGE_HISTORY;
+import static android.content.pm.PackageManager.PERMISSION_GRANTED;
+import static android.net.NetworkStats.UID_ALL;
+import static android.net.TrafficStats.UID_REMOVED;
+import static android.net.TrafficStats.UID_TETHERING;
+
+import android.Manifest;
+import android.annotation.IntDef;
+import android.app.AppOpsManager;
+import android.app.admin.DevicePolicyManager;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Binder;
+import android.os.Process;
+import android.os.UserHandle;
+import android.telephony.TelephonyManager;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Utility methods for controlling access to network stats APIs.
+ *
+ * @hide
+ */
+public final class NetworkStatsAccess {
+    private NetworkStatsAccess() {}
+
+    /**
+     * Represents an access level for the network usage history and statistics APIs.
+     *
+     * <p>Access levels are in increasing order; that is, it is reasonable to check access by
+     * verifying that the caller's access level is at least the minimum required level.
+     */
+    @IntDef({
+            Level.DEFAULT,
+            Level.USER,
+            Level.DEVICESUMMARY,
+            Level.DEVICE,
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface Level {
+        /**
+         * Default, unprivileged access level.
+         *
+         * <p>Can only access usage for one's own UID.
+         *
+         * <p>Every app will have at least this access level.
+         */
+        int DEFAULT = 0;
+
+        /**
+         * Access level for apps which can access usage for any app running in the same user.
+         *
+         * <p>Granted to:
+         * <ul>
+         * <li>Profile owners.
+         * </ul>
+         */
+        int USER = 1;
+
+        /**
+         * Access level for apps which can access usage summary of device. Device summary includes
+         * usage by apps running in any profiles/users, however this access level does not
+         * allow querying usage of individual apps running in other profiles/users.
+         *
+         * <p>Granted to:
+         * <ul>
+         * <li>Apps with the PACKAGE_USAGE_STATS permission granted. Note that this is an AppOps bit
+         * so it is not necessarily sufficient to declare this in the manifest.
+         * <li>Apps with the (signature/privileged) READ_NETWORK_USAGE_HISTORY permission.
+         * </ul>
+         */
+        int DEVICESUMMARY = 2;
+
+        /**
+         * Access level for apps which can access usage for any app on the device, including apps
+         * running on other users/profiles.
+         *
+         * <p>Granted to:
+         * <ul>
+         * <li>Device owners.
+         * <li>Carrier-privileged applications.
+         * <li>The system UID.
+         * </ul>
+         */
+        int DEVICE = 3;
+    }
+
+    /** Returns the {@link NetworkStatsAccess.Level} for the given caller. */
+    public static @NetworkStatsAccess.Level int checkAccessLevel(
+            Context context, int callingPid, int callingUid, String callingPackage) {
+        final DevicePolicyManager mDpm = context.getSystemService(DevicePolicyManager.class);
+        final TelephonyManager tm = (TelephonyManager)
+                context.getSystemService(Context.TELEPHONY_SERVICE);
+        boolean hasCarrierPrivileges;
+        final long token = Binder.clearCallingIdentity();
+        try {
+            hasCarrierPrivileges = tm != null
+                    && tm.checkCarrierPrivilegesForPackageAnyPhone(callingPackage)
+                            == TelephonyManager.CARRIER_PRIVILEGE_STATUS_HAS_ACCESS;
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+
+        final boolean isDeviceOwner = mDpm != null && mDpm.isDeviceOwnerApp(callingPackage);
+        final int appId = UserHandle.getAppId(callingUid);
+
+        final boolean isNetworkStack = context.checkPermission(
+                android.Manifest.permission.NETWORK_STACK, callingPid, callingUid)
+                == PERMISSION_GRANTED;
+
+        if (hasCarrierPrivileges || isDeviceOwner
+                || appId == Process.SYSTEM_UID || isNetworkStack) {
+            // Carrier-privileged apps and device owners, and the system (including the
+            // network stack) can access data usage for all apps on the device.
+            return NetworkStatsAccess.Level.DEVICE;
+        }
+
+        boolean hasAppOpsPermission = hasAppOpsPermission(context, callingUid, callingPackage);
+        if (hasAppOpsPermission || context.checkCallingOrSelfPermission(
+                READ_NETWORK_USAGE_HISTORY) == PackageManager.PERMISSION_GRANTED) {
+            return NetworkStatsAccess.Level.DEVICESUMMARY;
+        }
+
+        //TODO(b/169395065) Figure out if this flow makes sense in Device Owner mode.
+        boolean isProfileOwner = mDpm != null && (mDpm.isProfileOwnerApp(callingPackage)
+                || mDpm.isDeviceOwnerApp(callingPackage));
+        if (isProfileOwner) {
+            // Apps with the AppOps permission, profile owners, and apps with the privileged
+            // permission can access data usage for all apps in this user/profile.
+            return NetworkStatsAccess.Level.USER;
+        }
+
+        // Everyone else gets default access (only to their own UID).
+        return NetworkStatsAccess.Level.DEFAULT;
+    }
+
+    /**
+     * Returns whether the given caller should be able to access the given UID when the caller has
+     * the given {@link NetworkStatsAccess.Level}.
+     */
+    public static boolean isAccessibleToUser(int uid, int callerUid,
+            @NetworkStatsAccess.Level int accessLevel) {
+        final int userId = UserHandle.getUserHandleForUid(uid).getIdentifier();
+        final int callerUserId = UserHandle.getUserHandleForUid(callerUid).getIdentifier();
+        switch (accessLevel) {
+            case NetworkStatsAccess.Level.DEVICE:
+                // Device-level access - can access usage for any uid.
+                return true;
+            case NetworkStatsAccess.Level.DEVICESUMMARY:
+                // Can access usage for any app running in the same user, along
+                // with some special uids (system, removed, or tethering) and
+                // anonymized uids
+                return uid == android.os.Process.SYSTEM_UID || uid == UID_REMOVED
+                        || uid == UID_TETHERING || uid == UID_ALL
+                        || userId == callerUserId;
+            case NetworkStatsAccess.Level.USER:
+                // User-level access - can access usage for any app running in the same user, along
+                // with some special uids (system, removed, or tethering).
+                return uid == android.os.Process.SYSTEM_UID || uid == UID_REMOVED
+                        || uid == UID_TETHERING
+                        || userId == callerUserId;
+            case NetworkStatsAccess.Level.DEFAULT:
+            default:
+                // Default access level - can only access one's own usage.
+                return uid == callerUid;
+        }
+    }
+
+    private static boolean hasAppOpsPermission(
+            Context context, int callingUid, String callingPackage) {
+        if (callingPackage != null) {
+            AppOpsManager appOps = (AppOpsManager) context.getSystemService(
+                    Context.APP_OPS_SERVICE);
+
+            final int mode = appOps.noteOp(AppOpsManager.OPSTR_GET_USAGE_STATS,
+                    callingUid, callingPackage, null /* attributionTag */, null /* message */);
+            if (mode == AppOpsManager.MODE_DEFAULT) {
+                // The default behavior here is to check if PackageManager has given the app
+                // permission.
+                final int permissionCheck = context.checkCallingPermission(
+                        Manifest.permission.PACKAGE_USAGE_STATS);
+                return permissionCheck == PackageManager.PERMISSION_GRANTED;
+            }
+            return (mode == AppOpsManager.MODE_ALLOWED);
+        }
+        return false;
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStatsCollection.java b/framework-t/src/android/net/NetworkStatsCollection.java
new file mode 100644
index 0000000..e385b33
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsCollection.java
@@ -0,0 +1,956 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.NetworkStats.DEFAULT_NETWORK_NO;
+import static android.net.NetworkStats.DEFAULT_NETWORK_YES;
+import static android.net.NetworkStats.IFACE_ALL;
+import static android.net.NetworkStats.METERED_NO;
+import static android.net.NetworkStats.METERED_YES;
+import static android.net.NetworkStats.ROAMING_NO;
+import static android.net.NetworkStats.ROAMING_YES;
+import static android.net.NetworkStats.SET_ALL;
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.NetworkStats.UID_ALL;
+import static android.net.TrafficStats.UID_REMOVED;
+import static android.text.format.DateUtils.WEEK_IN_MILLIS;
+
+import static com.android.net.module.util.NetworkStatsUtils.multiplySafeByRational;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.net.NetworkStats.State;
+import android.net.NetworkStatsHistory.Entry;
+import android.os.Binder;
+import android.service.NetworkStatsCollectionKeyProto;
+import android.service.NetworkStatsCollectionProto;
+import android.service.NetworkStatsCollectionStatsProto;
+import android.telephony.SubscriptionPlan;
+import android.text.format.DateUtils;
+import android.util.ArrayMap;
+import android.util.AtomicFile;
+import android.util.IndentingPrintWriter;
+import android.util.Log;
+import android.util.Range;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.FileRotator;
+import com.android.net.module.util.CollectionUtils;
+import com.android.net.module.util.NetworkStatsUtils;
+
+import libcore.io.IoUtils;
+
+import java.io.BufferedInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutput;
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+import java.net.ProtocolException;
+import java.time.ZonedDateTime;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * Collection of {@link NetworkStatsHistory}, stored based on combined key of
+ * {@link NetworkIdentitySet}, UID, set, and tag. Knows how to persist itself.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public class NetworkStatsCollection implements FileRotator.Reader, FileRotator.Writer {
+    private static final String TAG = NetworkStatsCollection.class.getSimpleName();
+    /** File header magic number: "ANET" */
+    private static final int FILE_MAGIC = 0x414E4554;
+
+    private static final int VERSION_NETWORK_INIT = 1;
+
+    private static final int VERSION_UID_INIT = 1;
+    private static final int VERSION_UID_WITH_IDENT = 2;
+    private static final int VERSION_UID_WITH_TAG = 3;
+    private static final int VERSION_UID_WITH_SET = 4;
+
+    private static final int VERSION_UNIFIED_INIT = 16;
+
+    private ArrayMap<Key, NetworkStatsHistory> mStats = new ArrayMap<>();
+
+    private final long mBucketDurationMillis;
+
+    private long mStartMillis;
+    private long mEndMillis;
+    private long mTotalBytes;
+    private boolean mDirty;
+
+    /**
+     * Construct a {@link NetworkStatsCollection} object.
+     *
+     * @param bucketDuration duration of the buckets in this object, in milliseconds.
+     * @hide
+     */
+    public NetworkStatsCollection(long bucketDurationMillis) {
+        mBucketDurationMillis = bucketDurationMillis;
+        reset();
+    }
+
+    /** @hide */
+    public void clear() {
+        reset();
+    }
+
+    /** @hide */
+    public void reset() {
+        mStats.clear();
+        mStartMillis = Long.MAX_VALUE;
+        mEndMillis = Long.MIN_VALUE;
+        mTotalBytes = 0;
+        mDirty = false;
+    }
+
+    /** @hide */
+    public long getStartMillis() {
+        return mStartMillis;
+    }
+
+    /**
+     * Return first atomic bucket in this collection, which is more conservative
+     * than {@link #mStartMillis}.
+     * @hide
+     */
+    public long getFirstAtomicBucketMillis() {
+        if (mStartMillis == Long.MAX_VALUE) {
+            return Long.MAX_VALUE;
+        } else {
+            return mStartMillis + mBucketDurationMillis;
+        }
+    }
+
+    /** @hide */
+    public long getEndMillis() {
+        return mEndMillis;
+    }
+
+    /** @hide */
+    public long getTotalBytes() {
+        return mTotalBytes;
+    }
+
+    /** @hide */
+    public boolean isDirty() {
+        return mDirty;
+    }
+
+    /** @hide */
+    public void clearDirty() {
+        mDirty = false;
+    }
+
+    /** @hide */
+    public boolean isEmpty() {
+        return mStartMillis == Long.MAX_VALUE && mEndMillis == Long.MIN_VALUE;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public long roundUp(long time) {
+        if (time == Long.MIN_VALUE || time == Long.MAX_VALUE
+                || time == SubscriptionPlan.TIME_UNKNOWN) {
+            return time;
+        } else {
+            final long mod = time % mBucketDurationMillis;
+            if (mod > 0) {
+                time -= mod;
+                time += mBucketDurationMillis;
+            }
+            return time;
+        }
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public long roundDown(long time) {
+        if (time == Long.MIN_VALUE || time == Long.MAX_VALUE
+                || time == SubscriptionPlan.TIME_UNKNOWN) {
+            return time;
+        } else {
+            final long mod = time % mBucketDurationMillis;
+            if (mod > 0) {
+                time -= mod;
+            }
+            return time;
+        }
+    }
+
+    /** @hide */
+    public int[] getRelevantUids(@NetworkStatsAccess.Level int accessLevel) {
+        return getRelevantUids(accessLevel, Binder.getCallingUid());
+    }
+
+    /** @hide */
+    public int[] getRelevantUids(@NetworkStatsAccess.Level int accessLevel,
+                final int callerUid) {
+        final ArrayList<Integer> uids = new ArrayList<>();
+        for (int i = 0; i < mStats.size(); i++) {
+            final Key key = mStats.keyAt(i);
+            if (NetworkStatsAccess.isAccessibleToUser(key.uid, callerUid, accessLevel)) {
+                int j = Collections.binarySearch(uids, new Integer(key.uid));
+
+                if (j < 0) {
+                    j = ~j;
+                    uids.add(j, key.uid);
+                }
+            }
+        }
+        return CollectionUtils.toIntArray(uids);
+    }
+
+    /**
+     * Combine all {@link NetworkStatsHistory} in this collection which match
+     * the requested parameters.
+     * @hide
+     */
+    public NetworkStatsHistory getHistory(NetworkTemplate template, SubscriptionPlan augmentPlan,
+            int uid, int set, int tag, int fields, long start, long end,
+            @NetworkStatsAccess.Level int accessLevel, int callerUid) {
+        if (!NetworkStatsAccess.isAccessibleToUser(uid, callerUid, accessLevel)) {
+            throw new SecurityException("Network stats history of uid " + uid
+                    + " is forbidden for caller " + callerUid);
+        }
+
+        // 180 days of history should be enough for anyone; if we end up needing
+        // more, we'll dynamically grow the history object.
+        final int bucketEstimate = (int) NetworkStatsUtils.constrain(
+                ((end - start) / mBucketDurationMillis), 0,
+                (180 * DateUtils.DAY_IN_MILLIS) / mBucketDurationMillis);
+        final NetworkStatsHistory combined = new NetworkStatsHistory(
+                mBucketDurationMillis, bucketEstimate, fields);
+
+        // shortcut when we know stats will be empty
+        if (start == end) return combined;
+
+        // Figure out the window of time that we should be augmenting (if any)
+        long augmentStart = SubscriptionPlan.TIME_UNKNOWN;
+        long augmentEnd = (augmentPlan != null) ? augmentPlan.getDataUsageTime()
+                : SubscriptionPlan.TIME_UNKNOWN;
+        // And if augmenting, we might need to collect more data to adjust with
+        long collectStart = start;
+        long collectEnd = end;
+
+        if (augmentEnd != SubscriptionPlan.TIME_UNKNOWN) {
+            final Iterator<Range<ZonedDateTime>> it = augmentPlan.cycleIterator();
+            while (it.hasNext()) {
+                final Range<ZonedDateTime> cycle = it.next();
+                final long cycleStart = cycle.getLower().toInstant().toEpochMilli();
+                final long cycleEnd = cycle.getUpper().toInstant().toEpochMilli();
+                if (cycleStart <= augmentEnd && augmentEnd < cycleEnd) {
+                    augmentStart = cycleStart;
+                    collectStart = Long.min(collectStart, augmentStart);
+                    collectEnd = Long.max(collectEnd, augmentEnd);
+                    break;
+                }
+            }
+        }
+
+        if (augmentStart != SubscriptionPlan.TIME_UNKNOWN) {
+            // Shrink augmentation window so we don't risk undercounting.
+            augmentStart = roundUp(augmentStart);
+            augmentEnd = roundDown(augmentEnd);
+            // Grow collection window so we get all the stats needed.
+            collectStart = roundDown(collectStart);
+            collectEnd = roundUp(collectEnd);
+        }
+
+        for (int i = 0; i < mStats.size(); i++) {
+            final Key key = mStats.keyAt(i);
+            if (key.uid == uid && NetworkStats.setMatches(set, key.set) && key.tag == tag
+                    && templateMatches(template, key.ident)) {
+                final NetworkStatsHistory value = mStats.valueAt(i);
+                combined.recordHistory(value, collectStart, collectEnd);
+            }
+        }
+
+        if (augmentStart != SubscriptionPlan.TIME_UNKNOWN) {
+            final NetworkStatsHistory.Entry entry = combined.getValues(
+                    augmentStart, augmentEnd, null);
+
+            // If we don't have any recorded data for this time period, give
+            // ourselves something to scale with.
+            if (entry.rxBytes == 0 || entry.txBytes == 0) {
+                combined.recordData(augmentStart, augmentEnd,
+                        new NetworkStats.Entry(1, 0, 1, 0, 0));
+                combined.getValues(augmentStart, augmentEnd, entry);
+            }
+
+            final long rawBytes = (entry.rxBytes + entry.txBytes) == 0 ? 1 :
+                    (entry.rxBytes + entry.txBytes);
+            final long rawRxBytes = entry.rxBytes == 0 ? 1 : entry.rxBytes;
+            final long rawTxBytes = entry.txBytes == 0 ? 1 : entry.txBytes;
+            final long targetBytes = augmentPlan.getDataUsageBytes();
+
+            final long targetRxBytes = multiplySafeByRational(targetBytes, rawRxBytes, rawBytes);
+            final long targetTxBytes = multiplySafeByRational(targetBytes, rawTxBytes, rawBytes);
+
+
+            // Scale all matching buckets to reach anchor target
+            final long beforeTotal = combined.getTotalBytes();
+            for (int i = 0; i < combined.size(); i++) {
+                combined.getValues(i, entry);
+                if (entry.bucketStart >= augmentStart
+                        && entry.bucketStart + entry.bucketDuration <= augmentEnd) {
+                    entry.rxBytes = multiplySafeByRational(
+                            targetRxBytes, entry.rxBytes, rawRxBytes);
+                    entry.txBytes = multiplySafeByRational(
+                            targetTxBytes, entry.txBytes, rawTxBytes);
+                    // We purposefully clear out packet counters to indicate
+                    // that this data has been augmented.
+                    entry.rxPackets = 0;
+                    entry.txPackets = 0;
+                    combined.setValues(i, entry);
+                }
+            }
+
+            final long deltaTotal = combined.getTotalBytes() - beforeTotal;
+            if (deltaTotal != 0) {
+                Log.d(TAG, "Augmented network usage by " + deltaTotal + " bytes");
+            }
+
+            // Finally we can slice data as originally requested
+            final NetworkStatsHistory sliced = new NetworkStatsHistory(
+                    mBucketDurationMillis, bucketEstimate, fields);
+            sliced.recordHistory(combined, start, end);
+            return sliced;
+        } else {
+            return combined;
+        }
+    }
+
+    /**
+     * Summarize all {@link NetworkStatsHistory} in this collection which match
+     * the requested parameters across the requested range.
+     *
+     * @param template - a predicate for filtering netstats.
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param accessLevel - caller access level.
+     * @param callerUid - caller UID.
+     * @hide
+     */
+    public NetworkStats getSummary(NetworkTemplate template, long start, long end,
+            @NetworkStatsAccess.Level int accessLevel, int callerUid) {
+        final long now = System.currentTimeMillis();
+
+        final NetworkStats stats = new NetworkStats(end - start, 24);
+
+        // shortcut when we know stats will be empty
+        if (start == end) return stats;
+
+        final NetworkStats.Entry entry = new NetworkStats.Entry();
+        NetworkStatsHistory.Entry historyEntry = null;
+
+        for (int i = 0; i < mStats.size(); i++) {
+            final Key key = mStats.keyAt(i);
+            if (templateMatches(template, key.ident)
+                    && NetworkStatsAccess.isAccessibleToUser(key.uid, callerUid, accessLevel)
+                    && key.set < NetworkStats.SET_DEBUG_START) {
+                final NetworkStatsHistory value = mStats.valueAt(i);
+                historyEntry = value.getValues(start, end, now, historyEntry);
+
+                entry.iface = IFACE_ALL;
+                entry.uid = key.uid;
+                entry.set = key.set;
+                entry.tag = key.tag;
+                entry.defaultNetwork = key.ident.areAllMembersOnDefaultNetwork()
+                        ? DEFAULT_NETWORK_YES : DEFAULT_NETWORK_NO;
+                entry.metered = key.ident.isAnyMemberMetered() ? METERED_YES : METERED_NO;
+                entry.roaming = key.ident.isAnyMemberRoaming() ? ROAMING_YES : ROAMING_NO;
+                entry.rxBytes = historyEntry.rxBytes;
+                entry.rxPackets = historyEntry.rxPackets;
+                entry.txBytes = historyEntry.txBytes;
+                entry.txPackets = historyEntry.txPackets;
+                entry.operations = historyEntry.operations;
+
+                if (!entry.isEmpty()) {
+                    stats.combineValues(entry);
+                }
+            }
+        }
+
+        return stats;
+    }
+
+    /**
+     * Record given {@link android.net.NetworkStats.Entry} into this collection.
+     * @hide
+     */
+    public void recordData(NetworkIdentitySet ident, int uid, int set, int tag, long start,
+            long end, NetworkStats.Entry entry) {
+        final NetworkStatsHistory history = findOrCreateHistory(ident, uid, set, tag);
+        history.recordData(start, end, entry);
+        noteRecordedHistory(history.getStart(), history.getEnd(), entry.rxBytes + entry.txBytes);
+    }
+
+    /**
+     * Record given {@link NetworkStatsHistory} into this collection.
+     *
+     * @hide
+     */
+    public void recordHistory(@NonNull Key key, @NonNull NetworkStatsHistory history) {
+        Objects.requireNonNull(key);
+        Objects.requireNonNull(history);
+        if (history.size() == 0) return;
+        noteRecordedHistory(history.getStart(), history.getEnd(), history.getTotalBytes());
+
+        NetworkStatsHistory target = mStats.get(key);
+        if (target == null) {
+            target = new NetworkStatsHistory(history.getBucketDuration());
+            mStats.put(key, target);
+        }
+        target.recordEntireHistory(history);
+    }
+
+    /**
+     * Record all {@link NetworkStatsHistory} contained in the given collection
+     * into this collection.
+     *
+     * @hide
+     */
+    public void recordCollection(@NonNull NetworkStatsCollection another) {
+        Objects.requireNonNull(another);
+        for (int i = 0; i < another.mStats.size(); i++) {
+            final Key key = another.mStats.keyAt(i);
+            final NetworkStatsHistory value = another.mStats.valueAt(i);
+            recordHistory(key, value);
+        }
+    }
+
+    private NetworkStatsHistory findOrCreateHistory(
+            NetworkIdentitySet ident, int uid, int set, int tag) {
+        final Key key = new Key(ident, uid, set, tag);
+        final NetworkStatsHistory existing = mStats.get(key);
+
+        // update when no existing, or when bucket duration changed
+        NetworkStatsHistory updated = null;
+        if (existing == null) {
+            updated = new NetworkStatsHistory(mBucketDurationMillis, 10);
+        } else if (existing.getBucketDuration() != mBucketDurationMillis) {
+            updated = new NetworkStatsHistory(existing, mBucketDurationMillis);
+        }
+
+        if (updated != null) {
+            mStats.put(key, updated);
+            return updated;
+        } else {
+            return existing;
+        }
+    }
+
+    /** @hide */
+    @Override
+    public void read(InputStream in) throws IOException {
+        read((DataInput) new DataInputStream(in));
+    }
+
+    private void read(DataInput in) throws IOException {
+        // verify file magic header intact
+        final int magic = in.readInt();
+        if (magic != FILE_MAGIC) {
+            throw new ProtocolException("unexpected magic: " + magic);
+        }
+
+        final int version = in.readInt();
+        switch (version) {
+            case VERSION_UNIFIED_INIT: {
+                // uid := size *(NetworkIdentitySet size *(uid set tag NetworkStatsHistory))
+                final int identSize = in.readInt();
+                for (int i = 0; i < identSize; i++) {
+                    final NetworkIdentitySet ident = new NetworkIdentitySet(in);
+
+                    final int size = in.readInt();
+                    for (int j = 0; j < size; j++) {
+                        final int uid = in.readInt();
+                        final int set = in.readInt();
+                        final int tag = in.readInt();
+
+                        final Key key = new Key(ident, uid, set, tag);
+                        final NetworkStatsHistory history = new NetworkStatsHistory(in);
+                        recordHistory(key, history);
+                    }
+                }
+                break;
+            }
+            default: {
+                throw new ProtocolException("unexpected version: " + version);
+            }
+        }
+    }
+
+    /** @hide */
+    @Override
+    public void write(OutputStream out) throws IOException {
+        write((DataOutput) new DataOutputStream(out));
+        out.flush();
+    }
+
+    private void write(DataOutput out) throws IOException {
+        // cluster key lists grouped by ident
+        final HashMap<NetworkIdentitySet, ArrayList<Key>> keysByIdent = new HashMap<>();
+        for (Key key : mStats.keySet()) {
+            ArrayList<Key> keys = keysByIdent.get(key.ident);
+            if (keys == null) {
+                keys = new ArrayList<>();
+                keysByIdent.put(key.ident, keys);
+            }
+            keys.add(key);
+        }
+
+        out.writeInt(FILE_MAGIC);
+        out.writeInt(VERSION_UNIFIED_INIT);
+
+        out.writeInt(keysByIdent.size());
+        for (NetworkIdentitySet ident : keysByIdent.keySet()) {
+            final ArrayList<Key> keys = keysByIdent.get(ident);
+            ident.writeToStream(out);
+
+            out.writeInt(keys.size());
+            for (Key key : keys) {
+                final NetworkStatsHistory history = mStats.get(key);
+                out.writeInt(key.uid);
+                out.writeInt(key.set);
+                out.writeInt(key.tag);
+                history.writeToStream(out);
+            }
+        }
+    }
+
+    /**
+     * Read legacy network summary statistics file format into the collection,
+     * See {@code NetworkStatsService#maybeUpgradeLegacyStatsLocked}.
+     *
+     * @deprecated
+     * @hide
+     */
+    @Deprecated
+    public void readLegacyNetwork(File file) throws IOException {
+        final AtomicFile inputFile = new AtomicFile(file);
+
+        DataInputStream in = null;
+        try {
+            in = new DataInputStream(new BufferedInputStream(inputFile.openRead()));
+
+            // verify file magic header intact
+            final int magic = in.readInt();
+            if (magic != FILE_MAGIC) {
+                throw new ProtocolException("unexpected magic: " + magic);
+            }
+
+            final int version = in.readInt();
+            switch (version) {
+                case VERSION_NETWORK_INIT: {
+                    // network := size *(NetworkIdentitySet NetworkStatsHistory)
+                    final int size = in.readInt();
+                    for (int i = 0; i < size; i++) {
+                        final NetworkIdentitySet ident = new NetworkIdentitySet(in);
+                        final NetworkStatsHistory history = new NetworkStatsHistory(in);
+
+                        final Key key = new Key(ident, UID_ALL, SET_ALL, TAG_NONE);
+                        recordHistory(key, history);
+                    }
+                    break;
+                }
+                default: {
+                    throw new ProtocolException("unexpected version: " + version);
+                }
+            }
+        } catch (FileNotFoundException e) {
+            // missing stats is okay, probably first boot
+        } finally {
+            IoUtils.closeQuietly(in);
+        }
+    }
+
+    /**
+     * Read legacy Uid statistics file format into the collection,
+     * See {@code NetworkStatsService#maybeUpgradeLegacyStatsLocked}.
+     *
+     * @deprecated
+     * @hide
+     */
+    @Deprecated
+    public void readLegacyUid(File file, boolean onlyTags) throws IOException {
+        final AtomicFile inputFile = new AtomicFile(file);
+
+        DataInputStream in = null;
+        try {
+            in = new DataInputStream(new BufferedInputStream(inputFile.openRead()));
+
+            // verify file magic header intact
+            final int magic = in.readInt();
+            if (magic != FILE_MAGIC) {
+                throw new ProtocolException("unexpected magic: " + magic);
+            }
+
+            final int version = in.readInt();
+            switch (version) {
+                case VERSION_UID_INIT: {
+                    // uid := size *(UID NetworkStatsHistory)
+
+                    // drop this data version, since we don't have a good
+                    // mapping into NetworkIdentitySet.
+                    break;
+                }
+                case VERSION_UID_WITH_IDENT: {
+                    // uid := size *(NetworkIdentitySet size *(UID NetworkStatsHistory))
+
+                    // drop this data version, since this version only existed
+                    // for a short time.
+                    break;
+                }
+                case VERSION_UID_WITH_TAG:
+                case VERSION_UID_WITH_SET: {
+                    // uid := size *(NetworkIdentitySet size *(uid set tag NetworkStatsHistory))
+                    final int identSize = in.readInt();
+                    for (int i = 0; i < identSize; i++) {
+                        final NetworkIdentitySet ident = new NetworkIdentitySet(in);
+
+                        final int size = in.readInt();
+                        for (int j = 0; j < size; j++) {
+                            final int uid = in.readInt();
+                            final int set = (version >= VERSION_UID_WITH_SET) ? in.readInt()
+                                    : SET_DEFAULT;
+                            final int tag = in.readInt();
+
+                            final Key key = new Key(ident, uid, set, tag);
+                            final NetworkStatsHistory history = new NetworkStatsHistory(in);
+
+                            if ((tag == TAG_NONE) != onlyTags) {
+                                recordHistory(key, history);
+                            }
+                        }
+                    }
+                    break;
+                }
+                default: {
+                    throw new ProtocolException("unexpected version: " + version);
+                }
+            }
+        } catch (FileNotFoundException e) {
+            // missing stats is okay, probably first boot
+        } finally {
+            IoUtils.closeQuietly(in);
+        }
+    }
+
+    /**
+     * Remove any {@link NetworkStatsHistory} attributed to the requested UID,
+     * moving any {@link NetworkStats#TAG_NONE} series to
+     * {@link TrafficStats#UID_REMOVED}.
+     * @hide
+     */
+    public void removeUids(int[] uids) {
+        final ArrayList<Key> knownKeys = new ArrayList<>();
+        knownKeys.addAll(mStats.keySet());
+
+        // migrate all UID stats into special "removed" bucket
+        for (Key key : knownKeys) {
+            if (CollectionUtils.contains(uids, key.uid)) {
+                // only migrate combined TAG_NONE history
+                if (key.tag == TAG_NONE) {
+                    final NetworkStatsHistory uidHistory = mStats.get(key);
+                    final NetworkStatsHistory removedHistory = findOrCreateHistory(
+                            key.ident, UID_REMOVED, SET_DEFAULT, TAG_NONE);
+                    removedHistory.recordEntireHistory(uidHistory);
+                }
+                mStats.remove(key);
+                mDirty = true;
+            }
+        }
+    }
+
+    private void noteRecordedHistory(long startMillis, long endMillis, long totalBytes) {
+        if (startMillis < mStartMillis) mStartMillis = startMillis;
+        if (endMillis > mEndMillis) mEndMillis = endMillis;
+        mTotalBytes += totalBytes;
+        mDirty = true;
+    }
+
+    private int estimateBuckets() {
+        return (int) (Math.min(mEndMillis - mStartMillis, WEEK_IN_MILLIS * 5)
+                / mBucketDurationMillis);
+    }
+
+    private ArrayList<Key> getSortedKeys() {
+        final ArrayList<Key> keys = new ArrayList<>();
+        keys.addAll(mStats.keySet());
+        Collections.sort(keys, (left, right) -> Key.compare(left, right));
+        return keys;
+    }
+
+    /** @hide */
+    public void dump(IndentingPrintWriter pw) {
+        for (Key key : getSortedKeys()) {
+            pw.print("ident="); pw.print(key.ident.toString());
+            pw.print(" uid="); pw.print(key.uid);
+            pw.print(" set="); pw.print(NetworkStats.setToString(key.set));
+            pw.print(" tag="); pw.println(NetworkStats.tagToString(key.tag));
+
+            final NetworkStatsHistory history = mStats.get(key);
+            pw.increaseIndent();
+            history.dump(pw, true);
+            pw.decreaseIndent();
+        }
+    }
+
+    /** @hide */
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        for (Key key : getSortedKeys()) {
+            final long startStats = proto.start(NetworkStatsCollectionProto.STATS);
+
+            // Key
+            final long startKey = proto.start(NetworkStatsCollectionStatsProto.KEY);
+            key.ident.dumpDebug(proto, NetworkStatsCollectionKeyProto.IDENTITY);
+            proto.write(NetworkStatsCollectionKeyProto.UID, key.uid);
+            proto.write(NetworkStatsCollectionKeyProto.SET, key.set);
+            proto.write(NetworkStatsCollectionKeyProto.TAG, key.tag);
+            proto.end(startKey);
+
+            // Value
+            final NetworkStatsHistory history = mStats.get(key);
+            history.dumpDebug(proto, NetworkStatsCollectionStatsProto.HISTORY);
+            proto.end(startStats);
+        }
+
+        proto.end(start);
+    }
+
+    /** @hide */
+    public void dumpCheckin(PrintWriter pw, long start, long end) {
+        dumpCheckin(pw, start, end, NetworkTemplate.buildTemplateMobileWildcard(), "cell");
+        dumpCheckin(pw, start, end, NetworkTemplate.buildTemplateWifiWildcard(), "wifi");
+        dumpCheckin(pw, start, end, NetworkTemplate.buildTemplateEthernet(), "eth");
+        dumpCheckin(pw, start, end, NetworkTemplate.buildTemplateBluetooth(), "bt");
+    }
+
+    /**
+     * Dump all contained stats that match requested parameters, but group
+     * together all matching {@link NetworkTemplate} under a single prefix.
+     */
+    private void dumpCheckin(PrintWriter pw, long start, long end, NetworkTemplate groupTemplate,
+            String groupPrefix) {
+        final ArrayMap<Key, NetworkStatsHistory> grouped = new ArrayMap<>();
+
+        // Walk through all history, grouping by matching network templates
+        for (int i = 0; i < mStats.size(); i++) {
+            final Key key = mStats.keyAt(i);
+            final NetworkStatsHistory value = mStats.valueAt(i);
+
+            if (!templateMatches(groupTemplate, key.ident)) continue;
+            if (key.set >= NetworkStats.SET_DEBUG_START) continue;
+
+            final Key groupKey = new Key(null, key.uid, key.set, key.tag);
+            NetworkStatsHistory groupHistory = grouped.get(groupKey);
+            if (groupHistory == null) {
+                groupHistory = new NetworkStatsHistory(value.getBucketDuration());
+                grouped.put(groupKey, groupHistory);
+            }
+            groupHistory.recordHistory(value, start, end);
+        }
+
+        for (int i = 0; i < grouped.size(); i++) {
+            final Key key = grouped.keyAt(i);
+            final NetworkStatsHistory value = grouped.valueAt(i);
+
+            if (value.size() == 0) continue;
+
+            pw.print("c,");
+            pw.print(groupPrefix); pw.print(',');
+            pw.print(key.uid); pw.print(',');
+            pw.print(NetworkStats.setToCheckinString(key.set)); pw.print(',');
+            pw.print(key.tag);
+            pw.println();
+
+            value.dumpCheckin(pw);
+        }
+    }
+
+    /**
+     * Test if given {@link NetworkTemplate} matches any {@link NetworkIdentity}
+     * in the given {@link NetworkIdentitySet}.
+     */
+    private static boolean templateMatches(NetworkTemplate template, NetworkIdentitySet identSet) {
+        for (NetworkIdentity ident : identSet) {
+            if (template.matches(ident)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Get the all historical stats of the collection {@link NetworkStatsCollection}.
+     *
+     * @return All {@link NetworkStatsHistory} in this collection.
+     */
+    @NonNull
+    public Map<Key, NetworkStatsHistory> getEntries() {
+        return new ArrayMap(mStats);
+    }
+
+    /**
+     * Builder class for {@link NetworkStatsCollection}.
+     */
+    public static final class Builder {
+        private final long mBucketDurationMillis;
+        private final ArrayMap<Key, NetworkStatsHistory> mEntries = new ArrayMap<>();
+
+        /**
+         * Creates a new Builder with given bucket duration.
+         *
+         * @param bucketDuration Duration of the buckets of the object, in milliseconds.
+         */
+        public Builder(long bucketDurationMillis) {
+            mBucketDurationMillis = bucketDurationMillis;
+        }
+
+        /**
+         * Add association of the history with the specified key in this map.
+         *
+         * @param key The object used to identify a network, see {@link Key}.
+         * @param history {@link NetworkStatsHistory} instance associated to the given {@link Key}.
+         * @return The builder object.
+         */
+        @NonNull
+        public NetworkStatsCollection.Builder addEntry(@NonNull Key key,
+                @NonNull NetworkStatsHistory history) {
+            Objects.requireNonNull(key);
+            Objects.requireNonNull(history);
+            final List<Entry> historyEntries = history.getEntries();
+
+            final NetworkStatsHistory.Builder historyBuilder =
+                    new NetworkStatsHistory.Builder(mBucketDurationMillis, historyEntries.size());
+            for (Entry entry : historyEntries) {
+                historyBuilder.addEntry(entry);
+            }
+
+            mEntries.put(key, historyBuilder.build());
+            return this;
+        }
+
+        /**
+         * Builds the instance of the {@link NetworkStatsCollection}.
+         *
+         * @return the built instance of {@link NetworkStatsCollection}.
+         */
+        @NonNull
+        public NetworkStatsCollection build() {
+            final NetworkStatsCollection collection =
+                    new NetworkStatsCollection(mBucketDurationMillis);
+            for (int i = 0; i < mEntries.size(); i++) {
+                collection.recordHistory(mEntries.keyAt(i), mEntries.valueAt(i));
+            }
+            return collection;
+        }
+    }
+
+    /**
+     * the identifier that associate with the {@link NetworkStatsHistory} object to identify
+     * a certain record in the {@link NetworkStatsCollection} object.
+     */
+    public static final class Key {
+        /** @hide */
+        public final NetworkIdentitySet ident;
+        /** @hide */
+        public final int uid;
+        /** @hide */
+        public final int set;
+        /** @hide */
+        public final int tag;
+
+        private final int mHashCode;
+
+        /**
+         * Construct a {@link Key} object.
+         *
+         * @param ident a Set of {@link NetworkIdentity} that associated with the record.
+         * @param uid Uid of the record.
+         * @param set Set of the record, see {@code NetworkStats#SET_*}.
+         * @param tag Tag of the record, see {@link TrafficStats#setThreadStatsTag(int)}.
+         */
+        public Key(@NonNull Set<NetworkIdentity> ident, int uid, @State int set, int tag) {
+            this(new NetworkIdentitySet(Objects.requireNonNull(ident)), uid, set, tag);
+        }
+
+        /** @hide */
+        public Key(@NonNull NetworkIdentitySet ident, int uid, int set, int tag) {
+            this.ident = Objects.requireNonNull(ident);
+            this.uid = uid;
+            this.set = set;
+            this.tag = tag;
+            mHashCode = Objects.hash(ident, uid, set, tag);
+        }
+
+        @Override
+        public int hashCode() {
+            return mHashCode;
+        }
+
+        @Override
+        public boolean equals(@Nullable Object obj) {
+            if (obj instanceof Key) {
+                final Key key = (Key) obj;
+                return uid == key.uid && set == key.set && tag == key.tag
+                        && Objects.equals(ident, key.ident);
+            }
+            return false;
+        }
+
+        /** @hide */
+        public static int compare(@NonNull Key left, @NonNull Key right) {
+            Objects.requireNonNull(left);
+            Objects.requireNonNull(right);
+            int res = 0;
+            if (left.ident != null && right.ident != null) {
+                res = NetworkIdentitySet.compare(left.ident, right.ident);
+            }
+            if (res == 0) {
+                res = Integer.compare(left.uid, right.uid);
+            }
+            if (res == 0) {
+                res = Integer.compare(left.set, right.set);
+            }
+            if (res == 0) {
+                res = Integer.compare(left.tag, right.tag);
+            }
+            return res;
+        }
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStatsHistory.aidl b/framework-t/src/android/net/NetworkStatsHistory.aidl
new file mode 100644
index 0000000..8b9069f
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsHistory.aidl
@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2011, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable NetworkStatsHistory;
diff --git a/framework-t/src/android/net/NetworkStatsHistory.java b/framework-t/src/android/net/NetworkStatsHistory.java
new file mode 100644
index 0000000..301fef9
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsHistory.java
@@ -0,0 +1,1162 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.NetworkStats.IFACE_ALL;
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.NetworkStats.UID_ALL;
+import static android.net.NetworkStatsHistory.DataStreamUtils.readFullLongArray;
+import static android.net.NetworkStatsHistory.DataStreamUtils.readVarLongArray;
+import static android.net.NetworkStatsHistory.DataStreamUtils.writeVarLongArray;
+import static android.net.NetworkStatsHistory.Entry.UNKNOWN;
+import static android.net.NetworkStatsHistory.ParcelUtils.readLongArray;
+import static android.net.NetworkStatsHistory.ParcelUtils.writeLongArray;
+import static android.text.format.DateUtils.SECOND_IN_MILLIS;
+
+import static com.android.net.module.util.NetworkStatsUtils.multiplySafeByRational;
+
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.service.NetworkStatsHistoryBucketProto;
+import android.service.NetworkStatsHistoryProto;
+import android.util.IndentingPrintWriter;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.net.module.util.CollectionUtils;
+import com.android.net.module.util.NetworkStatsUtils;
+
+import libcore.util.EmptyArray;
+
+import java.io.CharArrayWriter;
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.net.ProtocolException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Random;
+
+/**
+ * Collection of historical network statistics, recorded into equally-sized
+ * "buckets" in time. Internally it stores data in {@code long} series for more
+ * efficient persistence.
+ * <p>
+ * Each bucket is defined by a {@link #bucketStart} timestamp, and lasts for
+ * {@link #bucketDuration}. Internally assumes that {@link #bucketStart} is
+ * sorted at all times.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class NetworkStatsHistory implements Parcelable {
+    private static final int VERSION_INIT = 1;
+    private static final int VERSION_ADD_PACKETS = 2;
+    private static final int VERSION_ADD_ACTIVE = 3;
+
+    /** @hide */
+    public static final int FIELD_ACTIVE_TIME = 0x01;
+    /** @hide */
+    public static final int FIELD_RX_BYTES = 0x02;
+    /** @hide */
+    public static final int FIELD_RX_PACKETS = 0x04;
+    /** @hide */
+    public static final int FIELD_TX_BYTES = 0x08;
+    /** @hide */
+    public static final int FIELD_TX_PACKETS = 0x10;
+    /** @hide */
+    public static final int FIELD_OPERATIONS = 0x20;
+    /** @hide */
+    public static final int FIELD_ALL = 0xFFFFFFFF;
+
+    private long bucketDuration;
+    private int bucketCount;
+    private long[] bucketStart;
+    private long[] activeTime;
+    private long[] rxBytes;
+    private long[] rxPackets;
+    private long[] txBytes;
+    private long[] txPackets;
+    private long[] operations;
+    private long totalBytes;
+
+    /** @hide */
+    public NetworkStatsHistory(long bucketDuration, long[] bucketStart, long[] activeTime,
+            long[] rxBytes, long[] rxPackets, long[] txBytes, long[] txPackets,
+            long[] operations, int bucketCount, long totalBytes) {
+        this.bucketDuration = bucketDuration;
+        this.bucketStart = bucketStart;
+        this.activeTime = activeTime;
+        this.rxBytes = rxBytes;
+        this.rxPackets = rxPackets;
+        this.txBytes = txBytes;
+        this.txPackets = txPackets;
+        this.operations = operations;
+        this.bucketCount = bucketCount;
+        this.totalBytes = totalBytes;
+    }
+
+    /**
+     * An instance to represent a single record in a {@link NetworkStatsHistory} object.
+     */
+    public static final class Entry {
+        /** @hide */
+        public static final long UNKNOWN = -1;
+
+        /** @hide */
+        // TODO: Migrate all callers to get duration from the history object and remove this field.
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long bucketDuration;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long bucketStart;
+        /** @hide */
+        public long activeTime;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long rxBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long rxPackets;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long txBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long txPackets;
+        /** @hide */
+        public long operations;
+        /** @hide */
+        Entry() {}
+
+        /**
+         * Construct a {@link Entry} instance to represent a single record in a
+         * {@link NetworkStatsHistory} object.
+         *
+         * @param bucketStart Start of period for this {@link Entry}, in milliseconds since the
+         *                    Unix epoch, see {@link java.lang.System#currentTimeMillis}.
+         * @param activeTime Active time for this {@link Entry}, in milliseconds.
+         * @param rxBytes Number of bytes received for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param rxPackets Number of packets received for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param txBytes Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param txPackets Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param operations count of network operations performed for this {@link Entry}. This can
+         *                   be used to derive bytes-per-operation.
+         */
+        public Entry(long bucketStart, long activeTime, long rxBytes,
+                long rxPackets, long txBytes, long txPackets, long operations) {
+            this.bucketStart = bucketStart;
+            this.activeTime = activeTime;
+            this.rxBytes = rxBytes;
+            this.rxPackets = rxPackets;
+            this.txBytes = txBytes;
+            this.txPackets = txPackets;
+            this.operations = operations;
+        }
+
+        /**
+         * Get start timestamp of the bucket's time interval, in milliseconds since the Unix epoch.
+         */
+        public long getBucketStart() {
+            return bucketStart;
+        }
+
+        /**
+         * Get active time of the bucket's time interval, in milliseconds.
+         */
+        public long getActiveTime() {
+            return activeTime;
+        }
+
+        /** Get number of bytes received for this {@link Entry}. */
+        public long getRxBytes() {
+            return rxBytes;
+        }
+
+        /** Get number of packets received for this {@link Entry}. */
+        public long getRxPackets() {
+            return rxPackets;
+        }
+
+        /** Get number of bytes transmitted for this {@link Entry}. */
+        public long getTxBytes() {
+            return txBytes;
+        }
+
+        /** Get number of packets transmitted for this {@link Entry}. */
+        public long getTxPackets() {
+            return txPackets;
+        }
+
+        /** Get count of network operations performed for this {@link Entry}. */
+        public long getOperations() {
+            return operations;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o.getClass() != getClass()) return false;
+            Entry entry = (Entry) o;
+            return bucketStart == entry.bucketStart
+                    && activeTime == entry.activeTime && rxBytes == entry.rxBytes
+                    && rxPackets == entry.rxPackets && txBytes == entry.txBytes
+                    && txPackets == entry.txPackets && operations == entry.operations;
+        }
+
+        @Override
+        public int hashCode() {
+            return (int) (bucketStart * 2
+                    + activeTime * 3
+                    + rxBytes * 5
+                    + rxPackets * 7
+                    + txBytes * 11
+                    + txPackets * 13
+                    + operations * 17);
+        }
+
+        @Override
+        public String toString() {
+            return "Entry{"
+                    + "bucketStart=" + bucketStart
+                    + ", activeTime=" + activeTime
+                    + ", rxBytes=" + rxBytes
+                    + ", rxPackets=" + rxPackets
+                    + ", txBytes=" + txBytes
+                    + ", txPackets=" + txPackets
+                    + ", operations=" + operations
+                    + "}";
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public NetworkStatsHistory(long bucketDuration) {
+        this(bucketDuration, 10, FIELD_ALL);
+    }
+
+    /** @hide */
+    public NetworkStatsHistory(long bucketDuration, int initialSize) {
+        this(bucketDuration, initialSize, FIELD_ALL);
+    }
+
+    /** @hide */
+    public NetworkStatsHistory(long bucketDuration, int initialSize, int fields) {
+        this.bucketDuration = bucketDuration;
+        bucketStart = new long[initialSize];
+        if ((fields & FIELD_ACTIVE_TIME) != 0) activeTime = new long[initialSize];
+        if ((fields & FIELD_RX_BYTES) != 0) rxBytes = new long[initialSize];
+        if ((fields & FIELD_RX_PACKETS) != 0) rxPackets = new long[initialSize];
+        if ((fields & FIELD_TX_BYTES) != 0) txBytes = new long[initialSize];
+        if ((fields & FIELD_TX_PACKETS) != 0) txPackets = new long[initialSize];
+        if ((fields & FIELD_OPERATIONS) != 0) operations = new long[initialSize];
+        bucketCount = 0;
+        totalBytes = 0;
+    }
+
+    /** @hide */
+    public NetworkStatsHistory(NetworkStatsHistory existing, long bucketDuration) {
+        this(bucketDuration, existing.estimateResizeBuckets(bucketDuration));
+        recordEntireHistory(existing);
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public NetworkStatsHistory(Parcel in) {
+        bucketDuration = in.readLong();
+        bucketStart = readLongArray(in);
+        activeTime = readLongArray(in);
+        rxBytes = readLongArray(in);
+        rxPackets = readLongArray(in);
+        txBytes = readLongArray(in);
+        txPackets = readLongArray(in);
+        operations = readLongArray(in);
+        bucketCount = bucketStart.length;
+        totalBytes = in.readLong();
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel out, int flags) {
+        out.writeLong(bucketDuration);
+        writeLongArray(out, bucketStart, bucketCount);
+        writeLongArray(out, activeTime, bucketCount);
+        writeLongArray(out, rxBytes, bucketCount);
+        writeLongArray(out, rxPackets, bucketCount);
+        writeLongArray(out, txBytes, bucketCount);
+        writeLongArray(out, txPackets, bucketCount);
+        writeLongArray(out, operations, bucketCount);
+        out.writeLong(totalBytes);
+    }
+
+    /** @hide */
+    public NetworkStatsHistory(DataInput in) throws IOException {
+        final int version = in.readInt();
+        switch (version) {
+            case VERSION_INIT: {
+                bucketDuration = in.readLong();
+                bucketStart = readFullLongArray(in);
+                rxBytes = readFullLongArray(in);
+                rxPackets = new long[bucketStart.length];
+                txBytes = readFullLongArray(in);
+                txPackets = new long[bucketStart.length];
+                operations = new long[bucketStart.length];
+                bucketCount = bucketStart.length;
+                totalBytes = CollectionUtils.total(rxBytes) + CollectionUtils.total(txBytes);
+                break;
+            }
+            case VERSION_ADD_PACKETS:
+            case VERSION_ADD_ACTIVE: {
+                bucketDuration = in.readLong();
+                bucketStart = readVarLongArray(in);
+                activeTime = (version >= VERSION_ADD_ACTIVE) ? readVarLongArray(in)
+                        : new long[bucketStart.length];
+                rxBytes = readVarLongArray(in);
+                rxPackets = readVarLongArray(in);
+                txBytes = readVarLongArray(in);
+                txPackets = readVarLongArray(in);
+                operations = readVarLongArray(in);
+                bucketCount = bucketStart.length;
+                totalBytes = CollectionUtils.total(rxBytes) + CollectionUtils.total(txBytes);
+                break;
+            }
+            default: {
+                throw new ProtocolException("unexpected version: " + version);
+            }
+        }
+
+        if (bucketStart.length != bucketCount || rxBytes.length != bucketCount
+                || rxPackets.length != bucketCount || txBytes.length != bucketCount
+                || txPackets.length != bucketCount || operations.length != bucketCount) {
+            throw new ProtocolException("Mismatched history lengths");
+        }
+    }
+
+    /** @hide */
+    public void writeToStream(DataOutput out) throws IOException {
+        out.writeInt(VERSION_ADD_ACTIVE);
+        out.writeLong(bucketDuration);
+        writeVarLongArray(out, bucketStart, bucketCount);
+        writeVarLongArray(out, activeTime, bucketCount);
+        writeVarLongArray(out, rxBytes, bucketCount);
+        writeVarLongArray(out, rxPackets, bucketCount);
+        writeVarLongArray(out, txBytes, bucketCount);
+        writeVarLongArray(out, txPackets, bucketCount);
+        writeVarLongArray(out, operations, bucketCount);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public int size() {
+        return bucketCount;
+    }
+
+    /** @hide */
+    public long getBucketDuration() {
+        return bucketDuration;
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public long getStart() {
+        if (bucketCount > 0) {
+            return bucketStart[0];
+        } else {
+            return Long.MAX_VALUE;
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public long getEnd() {
+        if (bucketCount > 0) {
+            return bucketStart[bucketCount - 1] + bucketDuration;
+        } else {
+            return Long.MIN_VALUE;
+        }
+    }
+
+    /**
+     * Return total bytes represented by this history.
+     * @hide
+     */
+    public long getTotalBytes() {
+        return totalBytes;
+    }
+
+    /**
+     * Return index of bucket that contains or is immediately before the
+     * requested time.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public int getIndexBefore(long time) {
+        int index = Arrays.binarySearch(bucketStart, 0, bucketCount, time);
+        if (index < 0) {
+            index = (~index) - 1;
+        } else {
+            index -= 1;
+        }
+        return NetworkStatsUtils.constrain(index, 0, bucketCount - 1);
+    }
+
+    /**
+     * Return index of bucket that contains or is immediately after the
+     * requested time.
+     * @hide
+     */
+    public int getIndexAfter(long time) {
+        int index = Arrays.binarySearch(bucketStart, 0, bucketCount, time);
+        if (index < 0) {
+            index = ~index;
+        } else {
+            index += 1;
+        }
+        return NetworkStatsUtils.constrain(index, 0, bucketCount - 1);
+    }
+
+    /**
+     * Return specific stats entry.
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public Entry getValues(int i, Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.bucketStart = bucketStart[i];
+        entry.bucketDuration = bucketDuration;
+        entry.activeTime = getLong(activeTime, i, UNKNOWN);
+        entry.rxBytes = getLong(rxBytes, i, UNKNOWN);
+        entry.rxPackets = getLong(rxPackets, i, UNKNOWN);
+        entry.txBytes = getLong(txBytes, i, UNKNOWN);
+        entry.txPackets = getLong(txPackets, i, UNKNOWN);
+        entry.operations = getLong(operations, i, UNKNOWN);
+        return entry;
+    }
+
+    /**
+     * Get List of {@link Entry} of the {@link NetworkStatsHistory} instance.
+     *
+     * @return
+     */
+    @NonNull
+    public List<Entry> getEntries() {
+        // TODO: Return a wrapper that uses this list instead, to prevent the returned result
+        //  from being changed.
+        final ArrayList<Entry> ret = new ArrayList<>(size());
+        for (int i = 0; i < size(); i++) {
+            ret.add(getValues(i, null /* recycle */));
+        }
+        return ret;
+    }
+
+    /** @hide */
+    public void setValues(int i, Entry entry) {
+        // Unwind old values
+        if (rxBytes != null) totalBytes -= rxBytes[i];
+        if (txBytes != null) totalBytes -= txBytes[i];
+
+        bucketStart[i] = entry.bucketStart;
+        setLong(activeTime, i, entry.activeTime);
+        setLong(rxBytes, i, entry.rxBytes);
+        setLong(rxPackets, i, entry.rxPackets);
+        setLong(txBytes, i, entry.txBytes);
+        setLong(txPackets, i, entry.txPackets);
+        setLong(operations, i, entry.operations);
+
+        // Apply new values
+        if (rxBytes != null) totalBytes += rxBytes[i];
+        if (txBytes != null) totalBytes += txBytes[i];
+    }
+
+    /**
+     * Record that data traffic occurred in the given time range. Will
+     * distribute across internal buckets, creating new buckets as needed.
+     * @hide
+     */
+    @Deprecated
+    public void recordData(long start, long end, long rxBytes, long txBytes) {
+        recordData(start, end, new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, 0L, txBytes, 0L, 0L));
+    }
+
+    /**
+     * Record that data traffic occurred in the given time range. Will
+     * distribute across internal buckets, creating new buckets as needed.
+     * @hide
+     */
+    public void recordData(long start, long end, NetworkStats.Entry entry) {
+        long rxBytes = entry.rxBytes;
+        long rxPackets = entry.rxPackets;
+        long txBytes = entry.txBytes;
+        long txPackets = entry.txPackets;
+        long operations = entry.operations;
+
+        if (entry.isNegative()) {
+            throw new IllegalArgumentException("tried recording negative data");
+        }
+        if (entry.isEmpty()) {
+            return;
+        }
+
+        // create any buckets needed by this range
+        ensureBuckets(start, end);
+        // Return fast if there is still no entry. This would typically happen when the start,
+        // end or duration are not valid values, e.g. start > end, negative duration value, etc.
+        if (bucketCount == 0) return;
+
+        // distribute data usage into buckets
+        long duration = end - start;
+        final int startIndex = getIndexAfter(end);
+        for (int i = startIndex; i >= 0; i--) {
+            final long curStart = bucketStart[i];
+            final long curEnd = curStart + bucketDuration;
+
+            // bucket is older than record; we're finished
+            if (curEnd < start) break;
+            // bucket is newer than record; keep looking
+            if (curStart > end) continue;
+
+            final long overlap = Math.min(curEnd, end) - Math.max(curStart, start);
+            if (overlap <= 0) continue;
+
+            // integer math each time is faster than floating point
+            final long fracRxBytes = multiplySafeByRational(rxBytes, overlap, duration);
+            final long fracRxPackets = multiplySafeByRational(rxPackets, overlap, duration);
+            final long fracTxBytes = multiplySafeByRational(txBytes, overlap, duration);
+            final long fracTxPackets = multiplySafeByRational(txPackets, overlap, duration);
+            final long fracOperations = multiplySafeByRational(operations, overlap, duration);
+
+
+            addLong(activeTime, i, overlap);
+            addLong(this.rxBytes, i, fracRxBytes); rxBytes -= fracRxBytes;
+            addLong(this.rxPackets, i, fracRxPackets); rxPackets -= fracRxPackets;
+            addLong(this.txBytes, i, fracTxBytes); txBytes -= fracTxBytes;
+            addLong(this.txPackets, i, fracTxPackets); txPackets -= fracTxPackets;
+            addLong(this.operations, i, fracOperations); operations -= fracOperations;
+
+            duration -= overlap;
+        }
+
+        totalBytes += entry.rxBytes + entry.txBytes;
+    }
+
+    /**
+     * Record an entire {@link NetworkStatsHistory} into this history. Usually
+     * for combining together stats for external reporting.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public void recordEntireHistory(NetworkStatsHistory input) {
+        recordHistory(input, Long.MIN_VALUE, Long.MAX_VALUE);
+    }
+
+    /**
+     * Record given {@link NetworkStatsHistory} into this history, copying only
+     * buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets.
+     * @hide
+     */
+    public void recordHistory(NetworkStatsHistory input, long start, long end) {
+        final NetworkStats.Entry entry = new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        for (int i = 0; i < input.bucketCount; i++) {
+            final long bucketStart = input.bucketStart[i];
+            final long bucketEnd = bucketStart + input.bucketDuration;
+
+            // skip when bucket is outside requested range
+            if (bucketStart < start || bucketEnd > end) continue;
+
+            entry.rxBytes = getLong(input.rxBytes, i, 0L);
+            entry.rxPackets = getLong(input.rxPackets, i, 0L);
+            entry.txBytes = getLong(input.txBytes, i, 0L);
+            entry.txPackets = getLong(input.txPackets, i, 0L);
+            entry.operations = getLong(input.operations, i, 0L);
+
+            recordData(bucketStart, bucketEnd, entry);
+        }
+    }
+
+    /**
+     * Ensure that buckets exist for given time range, creating as needed.
+     */
+    private void ensureBuckets(long start, long end) {
+        // normalize incoming range to bucket boundaries
+        start -= start % bucketDuration;
+        end += (bucketDuration - (end % bucketDuration)) % bucketDuration;
+
+        for (long now = start; now < end; now += bucketDuration) {
+            // try finding existing bucket
+            final int index = Arrays.binarySearch(bucketStart, 0, bucketCount, now);
+            if (index < 0) {
+                // bucket missing, create and insert
+                insertBucket(~index, now);
+            }
+        }
+    }
+
+    /**
+     * Insert new bucket at requested index and starting time.
+     */
+    private void insertBucket(int index, long start) {
+        // create more buckets when needed
+        if (bucketCount >= bucketStart.length) {
+            final int newLength = Math.max(bucketStart.length, 10) * 3 / 2;
+            bucketStart = Arrays.copyOf(bucketStart, newLength);
+            if (activeTime != null) activeTime = Arrays.copyOf(activeTime, newLength);
+            if (rxBytes != null) rxBytes = Arrays.copyOf(rxBytes, newLength);
+            if (rxPackets != null) rxPackets = Arrays.copyOf(rxPackets, newLength);
+            if (txBytes != null) txBytes = Arrays.copyOf(txBytes, newLength);
+            if (txPackets != null) txPackets = Arrays.copyOf(txPackets, newLength);
+            if (operations != null) operations = Arrays.copyOf(operations, newLength);
+        }
+
+        // create gap when inserting bucket in middle
+        if (index < bucketCount) {
+            final int dstPos = index + 1;
+            final int length = bucketCount - index;
+
+            System.arraycopy(bucketStart, index, bucketStart, dstPos, length);
+            if (activeTime != null) System.arraycopy(activeTime, index, activeTime, dstPos, length);
+            if (rxBytes != null) System.arraycopy(rxBytes, index, rxBytes, dstPos, length);
+            if (rxPackets != null) System.arraycopy(rxPackets, index, rxPackets, dstPos, length);
+            if (txBytes != null) System.arraycopy(txBytes, index, txBytes, dstPos, length);
+            if (txPackets != null) System.arraycopy(txPackets, index, txPackets, dstPos, length);
+            if (operations != null) System.arraycopy(operations, index, operations, dstPos, length);
+        }
+
+        bucketStart[index] = start;
+        setLong(activeTime, index, 0L);
+        setLong(rxBytes, index, 0L);
+        setLong(rxPackets, index, 0L);
+        setLong(txBytes, index, 0L);
+        setLong(txPackets, index, 0L);
+        setLong(operations, index, 0L);
+        bucketCount++;
+    }
+
+    /**
+     * Clear all data stored in this object.
+     * @hide
+     */
+    public void clear() {
+        bucketStart = EmptyArray.LONG;
+        if (activeTime != null) activeTime = EmptyArray.LONG;
+        if (rxBytes != null) rxBytes = EmptyArray.LONG;
+        if (rxPackets != null) rxPackets = EmptyArray.LONG;
+        if (txBytes != null) txBytes = EmptyArray.LONG;
+        if (txPackets != null) txPackets = EmptyArray.LONG;
+        if (operations != null) operations = EmptyArray.LONG;
+        bucketCount = 0;
+        totalBytes = 0;
+    }
+
+    /**
+     * Remove buckets older than requested cutoff.
+     * @hide
+     */
+    public void removeBucketsBefore(long cutoff) {
+        // TODO: Consider use getIndexBefore.
+        int i;
+        for (i = 0; i < bucketCount; i++) {
+            final long curStart = bucketStart[i];
+            final long curEnd = curStart + bucketDuration;
+
+            // cutoff happens before or during this bucket; everything before
+            // this bucket should be removed.
+            if (curEnd > cutoff) break;
+        }
+
+        if (i > 0) {
+            final int length = bucketStart.length;
+            bucketStart = Arrays.copyOfRange(bucketStart, i, length);
+            if (activeTime != null) activeTime = Arrays.copyOfRange(activeTime, i, length);
+            if (rxBytes != null) rxBytes = Arrays.copyOfRange(rxBytes, i, length);
+            if (rxPackets != null) rxPackets = Arrays.copyOfRange(rxPackets, i, length);
+            if (txBytes != null) txBytes = Arrays.copyOfRange(txBytes, i, length);
+            if (txPackets != null) txPackets = Arrays.copyOfRange(txPackets, i, length);
+            if (operations != null) operations = Arrays.copyOfRange(operations, i, length);
+            bucketCount -= i;
+
+            totalBytes = 0;
+            if (rxBytes != null) totalBytes += CollectionUtils.total(rxBytes);
+            if (txBytes != null) totalBytes += CollectionUtils.total(txBytes);
+        }
+    }
+
+    /**
+     * Return interpolated data usage across the requested range. Interpolates
+     * across buckets, so values may be rounded slightly.
+     *
+     * <p>If the active bucket is not completed yet, it returns the proportional value of it
+     * based on its duration and the {@code end} param.
+     *
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param recycle - entry instance for performance, could be null.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(long start, long end, Entry recycle) {
+        return getValues(start, end, Long.MAX_VALUE, recycle);
+    }
+
+    /**
+     * Return interpolated data usage across the requested range. Interpolates
+     * across buckets, so values may be rounded slightly.
+     *
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param now - current timestamp in milliseconds since the epoch (wall clock).
+     * @param recycle - entry instance for performance, could be null.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(long start, long end, long now, Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.bucketDuration = end - start;
+        entry.bucketStart = start;
+        entry.activeTime = activeTime != null ? 0 : UNKNOWN;
+        entry.rxBytes = rxBytes != null ? 0 : UNKNOWN;
+        entry.rxPackets = rxPackets != null ? 0 : UNKNOWN;
+        entry.txBytes = txBytes != null ? 0 : UNKNOWN;
+        entry.txPackets = txPackets != null ? 0 : UNKNOWN;
+        entry.operations = operations != null ? 0 : UNKNOWN;
+
+        // Return fast if there is no entry.
+        if (bucketCount == 0) return entry;
+
+        final int startIndex = getIndexAfter(end);
+        for (int i = startIndex; i >= 0; i--) {
+            final long curStart = bucketStart[i];
+            long curEnd = curStart + bucketDuration;
+
+            // bucket is older than request; we're finished
+            if (curEnd <= start) break;
+            // bucket is newer than request; keep looking
+            if (curStart >= end) continue;
+
+            // the active bucket is shorter then a normal completed bucket
+            if (curEnd > now) curEnd = now;
+            // usually this is simply bucketDuration
+            final long bucketSpan = curEnd - curStart;
+            // prevent division by zero
+            if (bucketSpan <= 0) continue;
+
+            final long overlapEnd = curEnd < end ? curEnd : end;
+            final long overlapStart = curStart > start ? curStart : start;
+            final long overlap = overlapEnd - overlapStart;
+            if (overlap <= 0) continue;
+
+            // integer math each time is faster than floating point
+            if (activeTime != null) {
+                entry.activeTime += multiplySafeByRational(activeTime[i], overlap, bucketSpan);
+            }
+            if (rxBytes != null) {
+                entry.rxBytes += multiplySafeByRational(rxBytes[i], overlap, bucketSpan);
+            }
+            if (rxPackets != null) {
+                entry.rxPackets += multiplySafeByRational(rxPackets[i], overlap, bucketSpan);
+            }
+            if (txBytes != null) {
+                entry.txBytes += multiplySafeByRational(txBytes[i], overlap, bucketSpan);
+            }
+            if (txPackets != null) {
+                entry.txPackets += multiplySafeByRational(txPackets[i], overlap, bucketSpan);
+            }
+            if (operations != null) {
+                entry.operations += multiplySafeByRational(operations[i], overlap, bucketSpan);
+            }
+        }
+        return entry;
+    }
+
+    /**
+     * @deprecated only for temporary testing
+     * @hide
+     */
+    @Deprecated
+    public void generateRandom(long start, long end, long bytes) {
+        final Random r = new Random();
+
+        final float fractionRx = r.nextFloat();
+        final long rxBytes = (long) (bytes * fractionRx);
+        final long txBytes = (long) (bytes * (1 - fractionRx));
+
+        final long rxPackets = rxBytes / 1024;
+        final long txPackets = txBytes / 1024;
+        final long operations = rxBytes / 2048;
+
+        generateRandom(start, end, rxBytes, rxPackets, txBytes, txPackets, operations, r);
+    }
+
+    /**
+     * @deprecated only for temporary testing
+     * @hide
+     */
+    @Deprecated
+    public void generateRandom(long start, long end, long rxBytes, long rxPackets, long txBytes,
+            long txPackets, long operations, Random r) {
+        ensureBuckets(start, end);
+
+        final NetworkStats.Entry entry = new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        while (rxBytes > 1024 || rxPackets > 128 || txBytes > 1024 || txPackets > 128
+                || operations > 32) {
+            final long curStart = randomLong(r, start, end);
+            final long curEnd = curStart + randomLong(r, 0, (end - curStart) / 2);
+
+            entry.rxBytes = randomLong(r, 0, rxBytes);
+            entry.rxPackets = randomLong(r, 0, rxPackets);
+            entry.txBytes = randomLong(r, 0, txBytes);
+            entry.txPackets = randomLong(r, 0, txPackets);
+            entry.operations = randomLong(r, 0, operations);
+
+            rxBytes -= entry.rxBytes;
+            rxPackets -= entry.rxPackets;
+            txBytes -= entry.txBytes;
+            txPackets -= entry.txPackets;
+            operations -= entry.operations;
+
+            recordData(curStart, curEnd, entry);
+        }
+    }
+
+    /** @hide */
+    public static long randomLong(Random r, long start, long end) {
+        return (long) (start + (r.nextFloat() * (end - start)));
+    }
+
+    /**
+     * Quickly determine if this history intersects with given window.
+     * @hide
+     */
+    public boolean intersects(long start, long end) {
+        final long dataStart = getStart();
+        final long dataEnd = getEnd();
+        if (start >= dataStart && start <= dataEnd) return true;
+        if (end >= dataStart && end <= dataEnd) return true;
+        if (dataStart >= start && dataStart <= end) return true;
+        if (dataEnd >= start && dataEnd <= end) return true;
+        return false;
+    }
+
+    /** @hide */
+    public void dump(IndentingPrintWriter pw, boolean fullHistory) {
+        pw.print("NetworkStatsHistory: bucketDuration=");
+        pw.println(bucketDuration / SECOND_IN_MILLIS);
+        pw.increaseIndent();
+
+        final int start = fullHistory ? 0 : Math.max(0, bucketCount - 32);
+        if (start > 0) {
+            pw.print("(omitting "); pw.print(start); pw.println(" buckets)");
+        }
+
+        for (int i = start; i < bucketCount; i++) {
+            pw.print("st="); pw.print(bucketStart[i] / SECOND_IN_MILLIS);
+            if (rxBytes != null) { pw.print(" rb="); pw.print(rxBytes[i]); }
+            if (rxPackets != null) { pw.print(" rp="); pw.print(rxPackets[i]); }
+            if (txBytes != null) { pw.print(" tb="); pw.print(txBytes[i]); }
+            if (txPackets != null) { pw.print(" tp="); pw.print(txPackets[i]); }
+            if (operations != null) { pw.print(" op="); pw.print(operations[i]); }
+            pw.println();
+        }
+
+        pw.decreaseIndent();
+    }
+
+    /** @hide */
+    public void dumpCheckin(PrintWriter pw) {
+        pw.print("d,");
+        pw.print(bucketDuration / SECOND_IN_MILLIS);
+        pw.println();
+
+        for (int i = 0; i < bucketCount; i++) {
+            pw.print("b,");
+            pw.print(bucketStart[i] / SECOND_IN_MILLIS); pw.print(',');
+            if (rxBytes != null) { pw.print(rxBytes[i]); } else { pw.print("*"); } pw.print(',');
+            if (rxPackets != null) { pw.print(rxPackets[i]); } else { pw.print("*"); } pw.print(',');
+            if (txBytes != null) { pw.print(txBytes[i]); } else { pw.print("*"); } pw.print(',');
+            if (txPackets != null) { pw.print(txPackets[i]); } else { pw.print("*"); } pw.print(',');
+            if (operations != null) { pw.print(operations[i]); } else { pw.print("*"); }
+            pw.println();
+        }
+    }
+
+    /** @hide */
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        proto.write(NetworkStatsHistoryProto.BUCKET_DURATION_MS, bucketDuration);
+
+        for (int i = 0; i < bucketCount; i++) {
+            final long startBucket = proto.start(NetworkStatsHistoryProto.BUCKETS);
+
+            proto.write(NetworkStatsHistoryBucketProto.BUCKET_START_MS,
+                    bucketStart[i]);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.RX_BYTES, rxBytes, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.RX_PACKETS, rxPackets, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.TX_BYTES, txBytes, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.TX_PACKETS, txPackets, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.OPERATIONS, operations, i);
+
+            proto.end(startBucket);
+        }
+
+        proto.end(start);
+    }
+
+    private static void dumpDebug(ProtoOutputStream proto, long tag, long[] array, int index) {
+        if (array != null) {
+            proto.write(tag, array[index]);
+        }
+    }
+
+    @Override
+    public String toString() {
+        final CharArrayWriter writer = new CharArrayWriter();
+        dump(new IndentingPrintWriter(writer, "  "), false);
+        return writer.toString();
+    }
+
+    @UnsupportedAppUsage
+    public static final @android.annotation.NonNull Creator<NetworkStatsHistory> CREATOR = new Creator<NetworkStatsHistory>() {
+        @Override
+        public NetworkStatsHistory createFromParcel(Parcel in) {
+            return new NetworkStatsHistory(in);
+        }
+
+        @Override
+        public NetworkStatsHistory[] newArray(int size) {
+            return new NetworkStatsHistory[size];
+        }
+    };
+
+    private static long getLong(long[] array, int i, long value) {
+        return array != null ? array[i] : value;
+    }
+
+    private static void setLong(long[] array, int i, long value) {
+        if (array != null) array[i] = value;
+    }
+
+    private static void addLong(long[] array, int i, long value) {
+        if (array != null) array[i] += value;
+    }
+
+    /** @hide */
+    public int estimateResizeBuckets(long newBucketDuration) {
+        return (int) (size() * getBucketDuration() / newBucketDuration);
+    }
+
+    /**
+     * Utility methods for interacting with {@link DataInputStream} and
+     * {@link DataOutputStream}, mostly dealing with writing partial arrays.
+     * @hide
+     */
+    public static class DataStreamUtils {
+        @Deprecated
+        public static long[] readFullLongArray(DataInput in) throws IOException {
+            final int size = in.readInt();
+            if (size < 0) throw new ProtocolException("negative array size");
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = in.readLong();
+            }
+            return values;
+        }
+
+        /**
+         * Read variable-length {@link Long} using protobuf-style approach.
+         */
+        public static long readVarLong(DataInput in) throws IOException {
+            int shift = 0;
+            long result = 0;
+            while (shift < 64) {
+                byte b = in.readByte();
+                result |= (long) (b & 0x7F) << shift;
+                if ((b & 0x80) == 0)
+                    return result;
+                shift += 7;
+            }
+            throw new ProtocolException("malformed long");
+        }
+
+        /**
+         * Write variable-length {@link Long} using protobuf-style approach.
+         */
+        public static void writeVarLong(DataOutput out, long value) throws IOException {
+            while (true) {
+                if ((value & ~0x7FL) == 0) {
+                    out.writeByte((int) value);
+                    return;
+                } else {
+                    out.writeByte(((int) value & 0x7F) | 0x80);
+                    value >>>= 7;
+                }
+            }
+        }
+
+        public static long[] readVarLongArray(DataInput in) throws IOException {
+            final int size = in.readInt();
+            if (size == -1) return null;
+            if (size < 0) throw new ProtocolException("negative array size");
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = readVarLong(in);
+            }
+            return values;
+        }
+
+        public static void writeVarLongArray(DataOutput out, long[] values, int size)
+                throws IOException {
+            if (values == null) {
+                out.writeInt(-1);
+                return;
+            }
+            if (size > values.length) {
+                throw new IllegalArgumentException("size larger than length");
+            }
+            out.writeInt(size);
+            for (int i = 0; i < size; i++) {
+                writeVarLong(out, values[i]);
+            }
+        }
+    }
+
+    /**
+     * Utility methods for interacting with {@link Parcel} structures, mostly
+     * dealing with writing partial arrays.
+     * @hide
+     */
+    public static class ParcelUtils {
+        public static long[] readLongArray(Parcel in) {
+            final int size = in.readInt();
+            if (size == -1) return null;
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = in.readLong();
+            }
+            return values;
+        }
+
+        public static void writeLongArray(Parcel out, long[] values, int size) {
+            if (values == null) {
+                out.writeInt(-1);
+                return;
+            }
+            if (size > values.length) {
+                throw new IllegalArgumentException("size larger than length");
+            }
+            out.writeInt(size);
+            for (int i = 0; i < size; i++) {
+                out.writeLong(values[i]);
+            }
+        }
+    }
+
+    /**
+     * Builder class for {@link NetworkStatsHistory}.
+     */
+    public static final class Builder {
+        private final long mBucketDuration;
+        private final List<Long> mBucketStart;
+        private final List<Long> mActiveTime;
+        private final List<Long> mRxBytes;
+        private final List<Long> mRxPackets;
+        private final List<Long> mTxBytes;
+        private final List<Long> mTxPackets;
+        private final List<Long> mOperations;
+
+        /**
+         * Creates a new Builder with given bucket duration and initial capacity to construct
+         * {@link NetworkStatsHistory} objects.
+         *
+         * @param bucketDuration Duration of the buckets of the object, in milliseconds.
+         * @param initialCapacity Estimated number of records.
+         */
+        public Builder(long bucketDuration, int initialCapacity) {
+            mBucketDuration = bucketDuration;
+            mBucketStart = new ArrayList<>(initialCapacity);
+            mActiveTime = new ArrayList<>(initialCapacity);
+            mRxBytes = new ArrayList<>(initialCapacity);
+            mRxPackets = new ArrayList<>(initialCapacity);
+            mTxBytes = new ArrayList<>(initialCapacity);
+            mTxPackets = new ArrayList<>(initialCapacity);
+            mOperations = new ArrayList<>(initialCapacity);
+        }
+
+        /**
+         * Add an {@link Entry} into the {@link NetworkStatsHistory} instance.
+         *
+         * @param entry The target {@link Entry} object.
+         * @return The builder object.
+         */
+        @NonNull
+        public Builder addEntry(@NonNull Entry entry) {
+            mBucketStart.add(entry.bucketStart);
+            mActiveTime.add(entry.activeTime);
+            mRxBytes.add(entry.rxBytes);
+            mRxPackets.add(entry.rxPackets);
+            mTxBytes.add(entry.txBytes);
+            mTxPackets.add(entry.txPackets);
+            mOperations.add(entry.operations);
+            return this;
+        }
+
+        private static long sum(@NonNull List<Long> list) {
+            long sum = 0;
+            for (long entry : list) {
+                sum += entry;
+            }
+            return sum;
+        }
+
+        /**
+         * Builds the instance of the {@link NetworkStatsHistory}.
+         *
+         * @return the built instance of {@link NetworkStatsHistory}.
+         */
+        @NonNull
+        public NetworkStatsHistory build() {
+            return new NetworkStatsHistory(mBucketDuration,
+                    CollectionUtils.toLongArray(mBucketStart),
+                    CollectionUtils.toLongArray(mActiveTime),
+                    CollectionUtils.toLongArray(mRxBytes),
+                    CollectionUtils.toLongArray(mRxPackets),
+                    CollectionUtils.toLongArray(mTxBytes),
+                    CollectionUtils.toLongArray(mTxPackets),
+                    CollectionUtils.toLongArray(mOperations),
+                    mBucketStart.size(),
+                    sum(mRxBytes) + sum(mTxBytes));
+        }
+    }
+}
diff --git a/framework-t/src/android/net/NetworkTemplate.java b/framework-t/src/android/net/NetworkTemplate.java
new file mode 100644
index 0000000..7b5afd7
--- /dev/null
+++ b/framework-t/src/android/net/NetworkTemplate.java
@@ -0,0 +1,1119 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+import static android.net.ConnectivityManager.TYPE_BLUETOOTH;
+import static android.net.ConnectivityManager.TYPE_ETHERNET;
+import static android.net.ConnectivityManager.TYPE_MOBILE;
+import static android.net.ConnectivityManager.TYPE_PROXY;
+import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.net.ConnectivityManager.TYPE_WIFI_P2P;
+import static android.net.ConnectivityManager.TYPE_WIMAX;
+import static android.net.NetworkIdentity.OEM_NONE;
+import static android.net.NetworkIdentity.OEM_PAID;
+import static android.net.NetworkIdentity.OEM_PRIVATE;
+import static android.net.NetworkStats.DEFAULT_NETWORK_ALL;
+import static android.net.NetworkStats.DEFAULT_NETWORK_NO;
+import static android.net.NetworkStats.DEFAULT_NETWORK_YES;
+import static android.net.NetworkStats.METERED_ALL;
+import static android.net.NetworkStats.METERED_NO;
+import static android.net.NetworkStats.METERED_YES;
+import static android.net.NetworkStats.ROAMING_ALL;
+import static android.net.NetworkStats.ROAMING_NO;
+import static android.net.NetworkStats.ROAMING_YES;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.app.usage.NetworkStatsManager;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.net.wifi.WifiInfo;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.text.TextUtils;
+import android.util.ArraySet;
+
+import com.android.net.module.util.CollectionUtils;
+import com.android.net.module.util.NetworkIdentityUtils;
+import com.android.net.module.util.NetworkStatsUtils;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.SortedSet;
+import java.util.TreeSet;
+
+/**
+ * Predicate used to match {@link NetworkIdentity}, usually when collecting
+ * statistics. (It should probably have been named {@code NetworkPredicate}.)
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class NetworkTemplate implements Parcelable {
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "MATCH_" }, value = {
+            MATCH_MOBILE,
+            MATCH_WIFI,
+            MATCH_ETHERNET,
+            MATCH_BLUETOOTH,
+            MATCH_PROXY,
+            MATCH_CARRIER,
+    })
+    public @interface TemplateMatchRule{}
+
+    /** Match rule to match cellular networks with given Subscriber Ids. */
+    public static final int MATCH_MOBILE = 1;
+    /** Match rule to match wifi networks. */
+    public static final int MATCH_WIFI = 4;
+    /** Match rule to match ethernet networks. */
+    public static final int MATCH_ETHERNET = 5;
+    /**
+     * Match rule to match all cellular networks.
+     *
+     * @hide
+     */
+    public static final int MATCH_MOBILE_WILDCARD = 6;
+    /**
+     * Match rule to match all wifi networks.
+     *
+     * @hide
+     */
+    public static final int MATCH_WIFI_WILDCARD = 7;
+    /** Match rule to match bluetooth networks. */
+    public static final int MATCH_BLUETOOTH = 8;
+    /**
+     * Match rule to match networks with {@link ConnectivityManager#TYPE_PROXY} as the legacy
+     * network type.
+     */
+    public static final int MATCH_PROXY = 9;
+    /**
+     * Match rule to match all networks with subscriberId inside the template. Some carriers
+     * may offer non-cellular networks like WiFi, which will be matched by this rule.
+     */
+    public static final int MATCH_CARRIER = 10;
+
+    // TODO: Remove this and replace all callers with WIFI_NETWORK_KEY_ALL.
+    /** @hide */
+    public static final String WIFI_NETWORKID_ALL = null;
+
+    /**
+     * Wi-Fi Network Key is never supposed to be null (if it is, it is a bug that
+     * should be fixed), so it's not possible to want to match null vs
+     * non-null. Therefore it's fine to use null as a sentinel for Wifi Network Key.
+     *
+     * @hide
+     */
+    public static final String WIFI_NETWORK_KEY_ALL = WIFI_NETWORKID_ALL;
+
+    /**
+     * Include all network types when filtering. This is meant to merge in with the
+     * {@code TelephonyManager.NETWORK_TYPE_*} constants, and thus needs to stay in sync.
+     */
+    public static final int NETWORK_TYPE_ALL = -1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "OEM_MANAGED_" }, value = {
+            OEM_MANAGED_ALL,
+            OEM_MANAGED_NO,
+            OEM_MANAGED_YES,
+            OEM_MANAGED_PAID,
+            OEM_MANAGED_PRIVATE
+    })
+    public @interface OemManaged{}
+
+    /**
+     * Value to match both OEM managed and unmanaged networks (all networks).
+     */
+    public static final int OEM_MANAGED_ALL = -1;
+    /**
+     * Value to match networks which are not OEM managed.
+     */
+    public static final int OEM_MANAGED_NO = OEM_NONE;
+    /**
+     * Value to match any OEM managed network.
+     */
+    public static final int OEM_MANAGED_YES = -2;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PAID}.
+     */
+    public static final int OEM_MANAGED_PAID = OEM_PAID;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PRIVATE}.
+     */
+    public static final int OEM_MANAGED_PRIVATE = OEM_PRIVATE;
+
+    private static boolean isKnownMatchRule(final int rule) {
+        switch (rule) {
+            case MATCH_MOBILE:
+            case MATCH_WIFI:
+            case MATCH_ETHERNET:
+            case MATCH_MOBILE_WILDCARD:
+            case MATCH_WIFI_WILDCARD:
+            case MATCH_BLUETOOTH:
+            case MATCH_PROXY:
+            case MATCH_CARRIER:
+                return true;
+
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Template to match {@link ConnectivityManager#TYPE_MOBILE} networks with
+     * the given IMSI.
+     *
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateMobileAll(String subscriberId) {
+        return new NetworkTemplate(MATCH_MOBILE, subscriberId, null);
+    }
+
+    /**
+     * Template to match cellular networks with the given IMSI, {@code ratType} and
+     * {@code metered}. Use {@link #NETWORK_TYPE_ALL} to include all network types when
+     * filtering. See {@code TelephonyManager.NETWORK_TYPE_*}.
+     *
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateMobileWithRatType(@Nullable String subscriberId,
+            int ratType, int metered) {
+        if (TextUtils.isEmpty(subscriberId)) {
+            return new NetworkTemplate(MATCH_MOBILE_WILDCARD, null /* subscriberId */,
+                    null /* matchSubscriberIds */,
+                    new String[0] /* matchWifiNetworkKeys */, metered, ROAMING_ALL,
+                    DEFAULT_NETWORK_ALL, ratType, OEM_MANAGED_ALL,
+                    NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+        }
+        return new NetworkTemplate(MATCH_MOBILE, subscriberId, new String[] { subscriberId },
+                new String[0] /* matchWifiNetworkKeys */,
+                metered, ROAMING_ALL, DEFAULT_NETWORK_ALL, ratType, OEM_MANAGED_ALL,
+                NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /**
+     * Template to match metered {@link ConnectivityManager#TYPE_MOBILE} networks,
+     * regardless of IMSI.
+     *
+     * @hide
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static NetworkTemplate buildTemplateMobileWildcard() {
+        return new NetworkTemplate(MATCH_MOBILE_WILDCARD, null, null);
+    }
+
+    /**
+     * Template to match all metered {@link ConnectivityManager#TYPE_WIFI} networks,
+     * regardless of key of the wifi network.
+     *
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateWifiWildcard() {
+        // TODO: Consider replace this with MATCH_WIFI with NETWORK_ID_ALL
+        // and SUBSCRIBER_ID_MATCH_RULE_ALL.
+        return new NetworkTemplate(MATCH_WIFI_WILDCARD, null, null);
+    }
+
+    /** @hide */
+    @Deprecated
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateWifi() {
+        return buildTemplateWifiWildcard();
+    }
+
+    /**
+     * Template to match {@link ConnectivityManager#TYPE_WIFI} networks with the
+     * given key of the wifi network.
+     *
+     * @param wifiNetworkKey key of the wifi network. see {@link WifiInfo#getNetworkKey()}
+     *                  to know details about the key.
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateWifi(@NonNull String wifiNetworkKey) {
+        Objects.requireNonNull(wifiNetworkKey);
+        return new NetworkTemplate(MATCH_WIFI, null /* subscriberId */,
+                new String[] { null } /* matchSubscriberIds */,
+                new String[] { wifiNetworkKey }, METERED_ALL, ROAMING_ALL,
+                DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_ALL);
+    }
+
+    /**
+     * Template to match all {@link ConnectivityManager#TYPE_WIFI} networks with the given
+     * key of the wifi network and IMSI.
+     *
+     * Call with {@link #WIFI_NETWORK_KEY_ALL} for {@code wifiNetworkKey} to get result regardless
+     * of key of the wifi network.
+     *
+     * @param wifiNetworkKey key of the wifi network. see {@link WifiInfo#getNetworkKey()}
+     *                  to know details about the key.
+     * @param subscriberId the IMSI associated to this wifi network.
+     *
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateWifi(@Nullable String wifiNetworkKey,
+            @Nullable String subscriberId) {
+        return new NetworkTemplate(MATCH_WIFI, subscriberId, new String[] { subscriberId },
+                wifiNetworkKey != null
+                        ? new String[] { wifiNetworkKey } : new String[0],
+                METERED_ALL, ROAMING_ALL, DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_ETHERNET} style
+     * networks together.
+     *
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateEthernet() {
+        return new NetworkTemplate(MATCH_ETHERNET, null, null);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_BLUETOOTH} style
+     * networks together.
+     *
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateBluetooth() {
+        return new NetworkTemplate(MATCH_BLUETOOTH, null, null);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_PROXY} style
+     * networks together.
+     *
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateProxy() {
+        return new NetworkTemplate(MATCH_PROXY, null, null);
+    }
+
+    /**
+     * Template to match all metered carrier networks with the given IMSI.
+     *
+     * @hide
+     */
+    public static NetworkTemplate buildTemplateCarrierMetered(@NonNull String subscriberId) {
+        Objects.requireNonNull(subscriberId);
+        return new NetworkTemplate(MATCH_CARRIER, subscriberId,
+                new String[] { subscriberId },
+                new String[0] /* matchWifiNetworkKeys */,
+                METERED_YES, ROAMING_ALL,
+                DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    private final int mMatchRule;
+    private final String mSubscriberId;
+
+    /**
+     * Ugh, templates are designed to target a single subscriber, but we might
+     * need to match several "merged" subscribers. These are the subscribers
+     * that should be considered to match this template.
+     * <p>
+     * Since the merge set is dynamic, it should <em>not</em> be persisted or
+     * used for determining equality.
+     */
+    private final String[] mMatchSubscriberIds;
+
+    @NonNull
+    private final String[] mMatchWifiNetworkKeys;
+
+    // Matches for the NetworkStats constants METERED_*, ROAMING_* and DEFAULT_NETWORK_*.
+    private final int mMetered;
+    private final int mRoaming;
+    private final int mDefaultNetwork;
+    private final int mRatType;
+    /**
+     * The subscriber Id match rule defines how the template should match networks with
+     * specific subscriberId(s). See NetworkTemplate#SUBSCRIBER_ID_MATCH_RULE_* for more detail.
+     */
+    private final int mSubscriberIdMatchRule;
+
+    // Bitfield containing OEM network properties{@code NetworkIdentity#OEM_*}.
+    private final int mOemManaged;
+
+    private static void checkValidSubscriberIdMatchRule(int matchRule, int subscriberIdMatchRule) {
+        switch (matchRule) {
+            case MATCH_MOBILE:
+            case MATCH_CARRIER:
+                // MOBILE and CARRIER templates must always specify a subscriber ID.
+                if (subscriberIdMatchRule == NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_ALL) {
+                    throw new IllegalArgumentException("Invalid SubscriberIdMatchRule "
+                            + "on match rule: " + getMatchRuleName(matchRule));
+                }
+                return;
+            default:
+                return;
+        }
+    }
+
+    /** @hide */
+    // TODO: Deprecate this constructor, mark it @UnsupportedAppUsage(maxTargetSdk = S)
+    @UnsupportedAppUsage
+    public NetworkTemplate(int matchRule, String subscriberId, String wifiNetworkKey) {
+        this(matchRule, subscriberId, new String[] { subscriberId }, wifiNetworkKey);
+    }
+
+    /** @hide */
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String wifiNetworkKey) {
+        // Older versions used to only match MATCH_MOBILE and MATCH_MOBILE_WILDCARD templates
+        // to metered networks. It is now possible to match mobile with any meteredness, but
+        // in order to preserve backward compatibility of @UnsupportedAppUsage methods, this
+        //constructor passes METERED_YES for these types.
+        this(matchRule, subscriberId, matchSubscriberIds,
+                wifiNetworkKey != null ? new String[] { wifiNetworkKey } : new String[0],
+                (matchRule == MATCH_MOBILE || matchRule == MATCH_MOBILE_WILDCARD) ? METERED_YES
+                : METERED_ALL , ROAMING_ALL, DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL,
+                OEM_MANAGED_ALL, NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /** @hide */
+    // TODO: Remove it after updating all of the caller.
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String wifiNetworkKey, int metered, int roaming, int defaultNetwork, int ratType,
+            int oemManaged) {
+        this(matchRule, subscriberId, matchSubscriberIds,
+                wifiNetworkKey != null ? new String[] { wifiNetworkKey } : new String[0],
+                metered, roaming, defaultNetwork, ratType, oemManaged,
+                NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /** @hide */
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String[] matchWifiNetworkKeys, int metered, int roaming,
+            int defaultNetwork, int ratType, int oemManaged, int subscriberIdMatchRule) {
+        Objects.requireNonNull(matchWifiNetworkKeys);
+        mMatchRule = matchRule;
+        mSubscriberId = subscriberId;
+        // TODO: Check whether mMatchSubscriberIds = null or mMatchSubscriberIds = {null} when
+        // mSubscriberId is null
+        mMatchSubscriberIds = matchSubscriberIds;
+        mMatchWifiNetworkKeys = matchWifiNetworkKeys;
+        mMetered = metered;
+        mRoaming = roaming;
+        mDefaultNetwork = defaultNetwork;
+        mRatType = ratType;
+        mOemManaged = oemManaged;
+        mSubscriberIdMatchRule = subscriberIdMatchRule;
+        checkValidSubscriberIdMatchRule(matchRule, subscriberIdMatchRule);
+        if (!isKnownMatchRule(matchRule)) {
+            throw new IllegalArgumentException("Unknown network template rule " + matchRule
+                    + " will not match any identity.");
+        }
+    }
+
+    private NetworkTemplate(Parcel in) {
+        mMatchRule = in.readInt();
+        mSubscriberId = in.readString();
+        mMatchSubscriberIds = in.createStringArray();
+        mMatchWifiNetworkKeys = in.createStringArray();
+        mMetered = in.readInt();
+        mRoaming = in.readInt();
+        mDefaultNetwork = in.readInt();
+        mRatType = in.readInt();
+        mOemManaged = in.readInt();
+        mSubscriberIdMatchRule = in.readInt();
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mMatchRule);
+        dest.writeString(mSubscriberId);
+        dest.writeStringArray(mMatchSubscriberIds);
+        dest.writeStringArray(mMatchWifiNetworkKeys);
+        dest.writeInt(mMetered);
+        dest.writeInt(mRoaming);
+        dest.writeInt(mDefaultNetwork);
+        dest.writeInt(mRatType);
+        dest.writeInt(mOemManaged);
+        dest.writeInt(mSubscriberIdMatchRule);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder("NetworkTemplate: ");
+        builder.append("matchRule=").append(getMatchRuleName(mMatchRule));
+        if (mSubscriberId != null) {
+            builder.append(", subscriberId=").append(
+                    NetworkIdentityUtils.scrubSubscriberId(mSubscriberId));
+        }
+        if (mMatchSubscriberIds != null) {
+            builder.append(", matchSubscriberIds=").append(
+                    Arrays.toString(NetworkIdentityUtils.scrubSubscriberIds(mMatchSubscriberIds)));
+        }
+        builder.append(", matchWifiNetworkKeys=").append(Arrays.toString(mMatchWifiNetworkKeys));
+        if (mMetered != METERED_ALL) {
+            builder.append(", metered=").append(NetworkStats.meteredToString(mMetered));
+        }
+        if (mRoaming != ROAMING_ALL) {
+            builder.append(", roaming=").append(NetworkStats.roamingToString(mRoaming));
+        }
+        if (mDefaultNetwork != DEFAULT_NETWORK_ALL) {
+            builder.append(", defaultNetwork=").append(NetworkStats.defaultNetworkToString(
+                    mDefaultNetwork));
+        }
+        if (mRatType != NETWORK_TYPE_ALL) {
+            builder.append(", ratType=").append(mRatType);
+        }
+        if (mOemManaged != OEM_MANAGED_ALL) {
+            builder.append(", oemManaged=").append(getOemManagedNames(mOemManaged));
+        }
+        builder.append(", subscriberIdMatchRule=")
+                .append(subscriberIdMatchRuleToString(mSubscriberIdMatchRule));
+        return builder.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mMatchRule, mSubscriberId, Arrays.hashCode(mMatchWifiNetworkKeys),
+                mMetered, mRoaming, mDefaultNetwork, mRatType, mOemManaged, mSubscriberIdMatchRule);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof NetworkTemplate) {
+            final NetworkTemplate other = (NetworkTemplate) obj;
+            return mMatchRule == other.mMatchRule
+                    && Objects.equals(mSubscriberId, other.mSubscriberId)
+                    && mMetered == other.mMetered
+                    && mRoaming == other.mRoaming
+                    && mDefaultNetwork == other.mDefaultNetwork
+                    && mRatType == other.mRatType
+                    && mOemManaged == other.mOemManaged
+                    && mSubscriberIdMatchRule == other.mSubscriberIdMatchRule
+                    && Arrays.equals(mMatchWifiNetworkKeys, other.mMatchWifiNetworkKeys);
+        }
+        return false;
+    }
+
+    private static String subscriberIdMatchRuleToString(int rule) {
+        switch (rule) {
+            case NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT:
+                return "EXACT_MATCH";
+            case NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_ALL:
+                return "ALL";
+            default:
+                return "Unknown rule " + rule;
+        }
+    }
+
+    /** @hide */
+    public boolean isMatchRuleMobile() {
+        switch (mMatchRule) {
+            case MATCH_MOBILE:
+            case MATCH_MOBILE_WILDCARD:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Get match rule of the template. See {@code MATCH_*}.
+     */
+    @UnsupportedAppUsage
+    public int getMatchRule() {
+        // Wildcard rules are not exposed. For external callers, convert wildcard rules to
+        // exposed rules before returning.
+        switch (mMatchRule) {
+            case MATCH_MOBILE_WILDCARD:
+                return MATCH_MOBILE;
+            case MATCH_WIFI_WILDCARD:
+                return MATCH_WIFI;
+            default:
+                return mMatchRule;
+        }
+    }
+
+    /**
+     * Get subscriber Id of the template.
+     * @hide
+     */
+    @Nullable
+    @UnsupportedAppUsage
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    /**
+     * Get set of subscriber Ids of the template.
+     */
+    @NonNull
+    public Set<String> getSubscriberIds() {
+        return new ArraySet<>(Arrays.asList(mMatchSubscriberIds));
+    }
+
+    /**
+     * Get the set of Wifi Network Keys of the template.
+     * See {@link WifiInfo#getNetworkKey()}.
+     */
+    @NonNull
+    public Set<String> getWifiNetworkKeys() {
+        return new ArraySet<>(Arrays.asList(mMatchWifiNetworkKeys));
+    }
+
+    /** @hide */
+    // TODO: Remove this and replace all callers with {@link #getWifiNetworkKeys()}.
+    @Nullable
+    public String getNetworkId() {
+        return getWifiNetworkKeys().isEmpty() ? null : getWifiNetworkKeys().iterator().next();
+    }
+
+    /**
+     * Get meteredness filter of the template.
+     */
+    @NetworkStats.Meteredness
+    public int getMeteredness() {
+        return mMetered;
+    }
+
+    /**
+     * Get roaming filter of the template.
+     */
+    @NetworkStats.Roaming
+    public int getRoaming() {
+        return mRoaming;
+    }
+
+    /**
+     * Get the default network status filter of the template.
+     */
+    @NetworkStats.DefaultNetwork
+    public int getDefaultNetworkStatus() {
+        return mDefaultNetwork;
+    }
+
+    /**
+     * Get the Radio Access Technology(RAT) type filter of the template.
+     */
+    public int getRatType() {
+        return mRatType;
+    }
+
+    /**
+     * Get the OEM managed filter of the template. See {@code OEM_MANAGED_*} or
+     * {@code android.net.NetworkIdentity#OEM_*}.
+     */
+    @OemManaged
+    public int getOemManaged() {
+        return mOemManaged;
+    }
+
+    /**
+     * Test if given {@link NetworkIdentity} matches this template.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public boolean matches(@NonNull NetworkIdentity ident) {
+        Objects.requireNonNull(ident);
+        if (!matchesMetered(ident)) return false;
+        if (!matchesRoaming(ident)) return false;
+        if (!matchesDefaultNetwork(ident)) return false;
+        if (!matchesOemNetwork(ident)) return false;
+
+        switch (mMatchRule) {
+            case MATCH_MOBILE:
+                return matchesMobile(ident);
+            case MATCH_WIFI:
+                return matchesWifi(ident);
+            case MATCH_ETHERNET:
+                return matchesEthernet(ident);
+            case MATCH_MOBILE_WILDCARD:
+                return matchesMobileWildcard(ident);
+            case MATCH_WIFI_WILDCARD:
+                return matchesWifiWildcard(ident);
+            case MATCH_BLUETOOTH:
+                return matchesBluetooth(ident);
+            case MATCH_PROXY:
+                return matchesProxy(ident);
+            case MATCH_CARRIER:
+                return matchesCarrier(ident);
+            default:
+                // We have no idea what kind of network template we are, so we
+                // just claim not to match anything.
+                return false;
+        }
+    }
+
+    private boolean matchesMetered(NetworkIdentity ident) {
+        return (mMetered == METERED_ALL)
+            || (mMetered == METERED_YES && ident.mMetered)
+            || (mMetered == METERED_NO && !ident.mMetered);
+    }
+
+    private boolean matchesRoaming(NetworkIdentity ident) {
+        return (mRoaming == ROAMING_ALL)
+            || (mRoaming == ROAMING_YES && ident.mRoaming)
+            || (mRoaming == ROAMING_NO && !ident.mRoaming);
+    }
+
+    private boolean matchesDefaultNetwork(NetworkIdentity ident) {
+        return (mDefaultNetwork == DEFAULT_NETWORK_ALL)
+            || (mDefaultNetwork == DEFAULT_NETWORK_YES && ident.mDefaultNetwork)
+            || (mDefaultNetwork == DEFAULT_NETWORK_NO && !ident.mDefaultNetwork);
+    }
+
+    private boolean matchesOemNetwork(NetworkIdentity ident) {
+        return (mOemManaged == OEM_MANAGED_ALL)
+            || (mOemManaged == OEM_MANAGED_YES
+                    && ident.mOemManaged != OEM_NONE)
+            || (mOemManaged == ident.mOemManaged);
+    }
+
+    private boolean matchesCollapsedRatType(NetworkIdentity ident) {
+        return mRatType == NETWORK_TYPE_ALL
+                || NetworkStatsManager.getCollapsedRatType(mRatType)
+                == NetworkStatsManager.getCollapsedRatType(ident.mRatType);
+    }
+
+    /**
+     * Check if this template matches {@code subscriberId}. Returns true if this
+     * template was created with {@code SUBSCRIBER_ID_MATCH_RULE_ALL}, or with a
+     * {@code mMatchSubscriberIds} array that contains {@code subscriberId}.
+     *
+     * @hide
+     */
+    public boolean matchesSubscriberId(@Nullable String subscriberId) {
+        return mSubscriberIdMatchRule == NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_ALL
+                || CollectionUtils.contains(mMatchSubscriberIds, subscriberId);
+    }
+
+    /**
+     * Check if network matches key of the wifi network.
+     * Returns true when the key matches, or when {@code mMatchWifiNetworkKeys} is
+     * empty.
+     *
+     * @param wifiNetworkKey key of the wifi network. see {@link WifiInfo#getNetworkKey()}
+     *                  to know details about the key.
+     */
+    private boolean matchesWifiNetworkKey(@NonNull String wifiNetworkKey) {
+        Objects.requireNonNull(wifiNetworkKey);
+        return CollectionUtils.isEmpty(mMatchWifiNetworkKeys)
+                || CollectionUtils.contains(mMatchWifiNetworkKeys, wifiNetworkKey);
+    }
+
+    /**
+     * Check if mobile network matches IMSI.
+     */
+    private boolean matchesMobile(NetworkIdentity ident) {
+        if (ident.mType == TYPE_WIMAX) {
+            // TODO: consider matching against WiMAX subscriber identity
+            return true;
+        } else {
+            return ident.mType == TYPE_MOBILE && !CollectionUtils.isEmpty(mMatchSubscriberIds)
+                    && CollectionUtils.contains(mMatchSubscriberIds, ident.mSubscriberId)
+                    && matchesCollapsedRatType(ident);
+        }
+    }
+
+    /**
+     * Check if matches Wi-Fi network template.
+     */
+    private boolean matchesWifi(NetworkIdentity ident) {
+        switch (ident.mType) {
+            case TYPE_WIFI:
+                return matchesSubscriberId(ident.mSubscriberId)
+                        && matchesWifiNetworkKey(ident.mWifiNetworkKey);
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Check if matches Ethernet network template.
+     */
+    private boolean matchesEthernet(NetworkIdentity ident) {
+        if (ident.mType == TYPE_ETHERNET) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Check if matches carrier network. The carrier networks means it includes the subscriberId.
+     */
+    private boolean matchesCarrier(NetworkIdentity ident) {
+        return ident.mSubscriberId != null
+                && !CollectionUtils.isEmpty(mMatchSubscriberIds)
+                && CollectionUtils.contains(mMatchSubscriberIds, ident.mSubscriberId);
+    }
+
+    private boolean matchesMobileWildcard(NetworkIdentity ident) {
+        if (ident.mType == TYPE_WIMAX) {
+            return true;
+        } else {
+            return ident.mType == TYPE_MOBILE && matchesCollapsedRatType(ident);
+        }
+    }
+
+    private boolean matchesWifiWildcard(NetworkIdentity ident) {
+        switch (ident.mType) {
+            case TYPE_WIFI:
+            case TYPE_WIFI_P2P:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Check if matches Bluetooth network template.
+     */
+    private boolean matchesBluetooth(NetworkIdentity ident) {
+        if (ident.mType == TYPE_BLUETOOTH) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Check if matches Proxy network template.
+     */
+    private boolean matchesProxy(NetworkIdentity ident) {
+        return ident.mType == TYPE_PROXY;
+    }
+
+    private static String getMatchRuleName(int matchRule) {
+        switch (matchRule) {
+            case MATCH_MOBILE:
+                return "MOBILE";
+            case MATCH_WIFI:
+                return "WIFI";
+            case MATCH_ETHERNET:
+                return "ETHERNET";
+            case MATCH_MOBILE_WILDCARD:
+                return "MOBILE_WILDCARD";
+            case MATCH_WIFI_WILDCARD:
+                return "WIFI_WILDCARD";
+            case MATCH_BLUETOOTH:
+                return "BLUETOOTH";
+            case MATCH_PROXY:
+                return "PROXY";
+            case MATCH_CARRIER:
+                return "CARRIER";
+            default:
+                return "UNKNOWN(" + matchRule + ")";
+        }
+    }
+
+    private static String getOemManagedNames(int oemManaged) {
+        switch (oemManaged) {
+            case OEM_MANAGED_ALL:
+                return "OEM_MANAGED_ALL";
+            case OEM_MANAGED_NO:
+                return "OEM_MANAGED_NO";
+            case OEM_MANAGED_YES:
+                return "OEM_MANAGED_YES";
+            default:
+                return NetworkIdentity.getOemManagedNames(oemManaged);
+        }
+    }
+
+    /**
+     * Examine the given template and normalize it.
+     * We pick the "lowest" merged subscriber as the primary
+     * for key purposes, and expand the template to match all other merged
+     * subscribers.
+     * <p>
+     * For example, given an incoming template matching B, and the currently
+     * active merge set [A,B], we'd return a new template that primarily matches
+     * A, but also matches B.
+     * TODO: remove and use {@link #normalize(NetworkTemplate, List)}.
+     *
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate normalize(NetworkTemplate template, String[] merged) {
+        return normalize(template, Arrays.<String[]>asList(merged));
+    }
+
+    /**
+     * Examine the given template and normalize it.
+     * We pick the "lowest" merged subscriber as the primary
+     * for key purposes, and expand the template to match all other merged
+     * subscribers.
+     *
+     * There can be multiple merged subscriberIds for multi-SIM devices.
+     *
+     * <p>
+     * For example, given an incoming template matching B, and the currently
+     * active merge set [A,B], we'd return a new template that primarily matches
+     * A, but also matches B.
+     *
+     * @hide
+     */
+    // TODO: @SystemApi when ready.
+    public static NetworkTemplate normalize(NetworkTemplate template, List<String[]> mergedList) {
+        // Now there are several types of network which uses SubscriberId to store network
+        // information. For instances:
+        // The TYPE_WIFI with subscriberId means that it is a merged carrier wifi network.
+        // The TYPE_CARRIER means that the network associate to specific carrier network.
+
+        if (template.mSubscriberId == null) return template;
+
+        for (String[] merged : mergedList) {
+            if (CollectionUtils.contains(merged, template.mSubscriberId)) {
+                // Requested template subscriber is part of the merge group; return
+                // a template that matches all merged subscribers.
+                final String[] matchWifiNetworkKeys = template.mMatchWifiNetworkKeys;
+                return new NetworkTemplate(template.mMatchRule, merged[0], merged,
+                        CollectionUtils.isEmpty(matchWifiNetworkKeys)
+                                ? null : matchWifiNetworkKeys[0]);
+            }
+        }
+
+        return template;
+    }
+
+    @UnsupportedAppUsage
+    public static final @android.annotation.NonNull Creator<NetworkTemplate> CREATOR = new Creator<NetworkTemplate>() {
+        @Override
+        public NetworkTemplate createFromParcel(Parcel in) {
+            return new NetworkTemplate(in);
+        }
+
+        @Override
+        public NetworkTemplate[] newArray(int size) {
+            return new NetworkTemplate[size];
+        }
+    };
+
+    /**
+     * Builder class for NetworkTemplate.
+     */
+    public static final class Builder {
+        private final int mMatchRule;
+        // Use a SortedSet to provide a deterministic order when fetching the first one.
+        @NonNull
+        private final SortedSet<String> mMatchSubscriberIds =
+                new TreeSet<>(Comparator.nullsFirst(Comparator.naturalOrder()));
+        @NonNull
+        private final SortedSet<String> mMatchWifiNetworkKeys = new TreeSet<>();
+
+        // Matches for the NetworkStats constants METERED_*, ROAMING_* and DEFAULT_NETWORK_*.
+        private int mMetered;
+        private int mRoaming;
+        private int mDefaultNetwork;
+        private int mRatType;
+
+        // Bitfield containing OEM network properties {@code NetworkIdentity#OEM_*}.
+        private int mOemManaged;
+
+        /**
+         * Creates a new Builder with given match rule to construct NetworkTemplate objects.
+         *
+         * @param matchRule the match rule of the template, see {@code MATCH_*}.
+         */
+        public Builder(@TemplateMatchRule final int matchRule) {
+            assertRequestableMatchRule(matchRule);
+            // Initialize members with default values.
+            mMatchRule = matchRule;
+            mMetered = METERED_ALL;
+            mRoaming = ROAMING_ALL;
+            mDefaultNetwork = DEFAULT_NETWORK_ALL;
+            mRatType = NETWORK_TYPE_ALL;
+            mOemManaged = OEM_MANAGED_ALL;
+        }
+
+        /**
+         * Set the Subscriber Ids. Calling this function with an empty set represents
+         * the intention of matching any Subscriber Ids.
+         *
+         * @param subscriberIds the list of Subscriber Ids.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setSubscriberIds(@NonNull Set<String> subscriberIds) {
+            Objects.requireNonNull(subscriberIds);
+            mMatchSubscriberIds.clear();
+            mMatchSubscriberIds.addAll(subscriberIds);
+            return this;
+        }
+
+        /**
+         * Set the Wifi Network Keys. Calling this function with an empty set represents
+         * the intention of matching any Wifi Network Key.
+         *
+         * @param wifiNetworkKeys the list of Wifi Network Key,
+         *                        see {@link WifiInfo#getNetworkKey()}.
+         *                        Or an empty list to match all networks.
+         *                        Note that {@code getNetworkKey()} might get null key
+         *                        when wifi disconnects. However, the caller should never invoke
+         *                        this function with a null Wifi Network Key since such statistics
+         *                        never exists.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setWifiNetworkKeys(@NonNull Set<String> wifiNetworkKeys) {
+            Objects.requireNonNull(wifiNetworkKeys);
+            for (String key : wifiNetworkKeys) {
+                if (key == null) {
+                    throw new IllegalArgumentException("Null is not a valid key");
+                }
+            }
+            mMatchWifiNetworkKeys.clear();
+            mMatchWifiNetworkKeys.addAll(wifiNetworkKeys);
+            return this;
+        }
+
+        /**
+         * Set the meteredness filter.
+         *
+         * @param metered the meteredness filter.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setMeteredness(@NetworkStats.Meteredness int metered) {
+            mMetered = metered;
+            return this;
+        }
+
+        /**
+         * Set the roaming filter.
+         *
+         * @param roaming the roaming filter.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setRoaming(@NetworkStats.Roaming int roaming) {
+            mRoaming = roaming;
+            return this;
+        }
+
+        /**
+         * Set the default network status filter.
+         *
+         * @param defaultNetwork the default network status filter.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setDefaultNetworkStatus(@NetworkStats.DefaultNetwork int defaultNetwork) {
+            mDefaultNetwork = defaultNetwork;
+            return this;
+        }
+
+        /**
+         * Set the Radio Access Technology(RAT) type filter.
+         *
+         * @param ratType the Radio Access Technology(RAT) type filter. Use
+         *                {@link #NETWORK_TYPE_ALL} to include all network types when filtering.
+         *                See {@code TelephonyManager.NETWORK_TYPE_*}.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setRatType(int ratType) {
+            // Input will be validated with the match rule when building the template.
+            mRatType = ratType;
+            return this;
+        }
+
+        /**
+         * Set the OEM managed filter.
+         *
+         * @param oemManaged the match rule to match different type of OEM managed network or
+         *                   unmanaged networks. See {@code OEM_MANAGED_*}.
+         * @return this builder.
+         */
+        @NonNull
+        public Builder setOemManaged(@OemManaged int oemManaged) {
+            mOemManaged = oemManaged;
+            return this;
+        }
+
+        /**
+         * Check whether the match rule is requestable.
+         *
+         * @param matchRule the target match rule to be checked.
+         */
+        private static void assertRequestableMatchRule(final int matchRule) {
+            if (!isKnownMatchRule(matchRule)
+                    || matchRule == MATCH_PROXY
+                    || matchRule == MATCH_MOBILE_WILDCARD
+                    || matchRule == MATCH_WIFI_WILDCARD) {
+                throw new IllegalArgumentException("Invalid match rule: "
+                        + getMatchRuleName(matchRule));
+            }
+        }
+
+        private void assertRequestableParameters() {
+            validateWifiNetworkKeys();
+            // TODO: Check all the input are legitimate.
+        }
+
+        private void validateWifiNetworkKeys() {
+            if (mMatchRule != MATCH_WIFI && !mMatchWifiNetworkKeys.isEmpty()) {
+                throw new IllegalArgumentException("Trying to build non wifi match rule: "
+                        + mMatchRule + " with wifi network keys");
+            }
+        }
+
+        /**
+         * For backward compatibility, deduce match rule to a wildcard match rule
+         * if the Subscriber Ids are empty.
+         */
+        private int getWildcardDeducedMatchRule() {
+            if (mMatchRule == MATCH_MOBILE && mMatchSubscriberIds.isEmpty()) {
+                return MATCH_MOBILE_WILDCARD;
+            } else if (mMatchRule == MATCH_WIFI && mMatchSubscriberIds.isEmpty()
+                    && mMatchWifiNetworkKeys.isEmpty()) {
+                return MATCH_WIFI_WILDCARD;
+            }
+            return mMatchRule;
+        }
+
+        /**
+         * Builds the instance of the NetworkTemplate.
+         *
+         * @return the built instance of NetworkTemplate.
+         */
+        @NonNull
+        public NetworkTemplate build() {
+            assertRequestableParameters();
+            final int subscriberIdMatchRule = mMatchSubscriberIds.isEmpty()
+                    ? NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_ALL
+                    : NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT;
+            return new NetworkTemplate(getWildcardDeducedMatchRule(),
+                    mMatchSubscriberIds.isEmpty() ? null : mMatchSubscriberIds.iterator().next(),
+                    mMatchSubscriberIds.toArray(new String[0]),
+                    mMatchWifiNetworkKeys.toArray(new String[0]), mMetered, mRoaming,
+                    mDefaultNetwork, mRatType, mOemManaged, subscriberIdMatchRule);
+        }
+    }
+}
diff --git a/framework-t/src/android/net/TrafficStats.java b/framework-t/src/android/net/TrafficStats.java
new file mode 100644
index 0000000..bc836d8
--- /dev/null
+++ b/framework-t/src/android/net/TrafficStats.java
@@ -0,0 +1,1148 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.NonNull;
+import android.annotation.SuppressLint;
+import android.annotation.SystemApi;
+import android.annotation.TestApi;
+import android.app.DownloadManager;
+import android.app.backup.BackupManager;
+import android.app.usage.NetworkStatsManager;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.content.Context;
+import android.media.MediaPlayer;
+import android.os.Binder;
+import android.os.Build;
+import android.os.RemoteException;
+import android.os.StrictMode;
+import android.util.Log;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.net.DatagramSocket;
+import java.net.Socket;
+import java.net.SocketException;
+
+/**
+ * Class that provides network traffic statistics. These statistics include
+ * bytes transmitted and received and network packets transmitted and received,
+ * over all interfaces, over the mobile interface, and on a per-UID basis.
+ * <p>
+ * These statistics may not be available on all platforms. If the statistics are
+ * not supported by this device, {@link #UNSUPPORTED} will be returned.
+ * <p>
+ * Note that the statistics returned by this class reset and start from zero
+ * after every reboot. To access more robust historical network statistics data,
+ * use {@link NetworkStatsManager} instead.
+ */
+public class TrafficStats {
+    static {
+        System.loadLibrary("framework-connectivity-tiramisu-jni");
+    }
+
+    private static final String TAG = TrafficStats.class.getSimpleName();
+    /**
+     * The return value to indicate that the device does not support the statistic.
+     */
+    public final static int UNSUPPORTED = -1;
+
+    /** @hide @deprecated use {@code DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long KB_IN_BYTES = 1024;
+    /** @hide @deprecated use {@code DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long MB_IN_BYTES = KB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@code DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long GB_IN_BYTES = MB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@code DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long TB_IN_BYTES = GB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@code DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long PB_IN_BYTES = TB_IN_BYTES * 1024;
+
+    /**
+     * Special UID value used when collecting {@link NetworkStatsHistory} for
+     * removed applications.
+     *
+     * @hide
+     */
+    public static final int UID_REMOVED = -4;
+
+    /**
+     * Special UID value used when collecting {@link NetworkStatsHistory} for
+     * tethering traffic.
+     *
+     * @hide
+     */
+    public static final int UID_TETHERING = NetworkStats.UID_TETHERING;
+
+    /**
+     * Tag values in this range are reserved for the network stack. The network stack is
+     * running as UID {@link android.os.Process.NETWORK_STACK_UID} when in the mainline
+     * module separate process, and as the system UID otherwise.
+     */
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_RANGE_START = 0xFFFFFD00;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_RANGE_END = 0xFFFFFEFF;
+
+    /**
+     * Tags between 0xFFFFFF00 and 0xFFFFFFFF are reserved and used internally by system services
+     * like DownloadManager when performing traffic on behalf of an application.
+     */
+    // Please note there is no enforcement of these constants, so do not rely on them to
+    // determine that the caller is a system caller.
+    /** @hide */
+    @SystemApi
+    public static final int TAG_SYSTEM_IMPERSONATION_RANGE_START = 0xFFFFFF00;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_SYSTEM_IMPERSONATION_RANGE_END = 0xFFFFFF0F;
+
+    /**
+     * Tag values between these ranges are reserved for the network stack to do traffic
+     * on behalf of applications. It is a subrange of the range above.
+     */
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_IMPERSONATION_RANGE_START = 0xFFFFFF80;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_IMPERSONATION_RANGE_END = 0xFFFFFF8F;
+
+    /**
+     * Default tag value for {@link DownloadManager} traffic.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_DOWNLOAD = 0xFFFFFF01;
+
+    /**
+     * Default tag value for {@link MediaPlayer} traffic.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_MEDIA = 0xFFFFFF02;
+
+    /**
+     * Default tag value for {@link BackupManager} backup traffic; that is,
+     * traffic from the device to the storage backend.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_BACKUP = 0xFFFFFF03;
+
+    /**
+     * Default tag value for {@link BackupManager} restore traffic; that is,
+     * app data retrieved from the storage backend at install time.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_RESTORE = 0xFFFFFF04;
+
+    /**
+     * Default tag value for code (typically APKs) downloaded by an app store on
+     * behalf of the app, such as updates.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_APP = 0xFFFFFF05;
+
+    // TODO : remove this constant when Wifi code is updated
+    /** @hide */
+    public static final int TAG_SYSTEM_PROBE = 0xFFFFFF42;
+
+    private static INetworkStatsService sStatsService;
+
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 130143562)
+    private synchronized static INetworkStatsService getStatsService() {
+        if (sStatsService == null) {
+            throw new IllegalStateException("TrafficStats not initialized, uid="
+                    + Binder.getCallingUid());
+        }
+        return sStatsService;
+    }
+
+    /**
+     * Snapshot of {@link NetworkStats} when the currently active profiling
+     * session started, or {@code null} if no session active.
+     *
+     * @see #startDataProfiling(Context)
+     * @see #stopDataProfiling(Context)
+     */
+    private static NetworkStats sActiveProfilingStart;
+
+    private static Object sProfilingLock = new Object();
+
+    private static final String LOOPBACK_IFACE = "lo";
+
+    /**
+     * Initialization {@link TrafficStats} with the context, to
+     * allow {@link TrafficStats} to fetch the needed binder.
+     *
+     * @param context a long-lived context, such as the application context or system
+     *                server context.
+     * @hide
+     */
+    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    @SuppressLint("VisiblySynchronized")
+    public static synchronized void init(@NonNull final Context context) {
+        if (sStatsService != null) {
+            throw new IllegalStateException("TrafficStats is already initialized, uid="
+                    + Binder.getCallingUid());
+        }
+        final NetworkStatsManager statsManager =
+                context.getSystemService(NetworkStatsManager.class);
+        if (statsManager == null) {
+            // TODO: Currently Process.isSupplemental is not working yet, because it depends on
+            //  process to run in a certain UID range, which is not true for now. Change this
+            //  to Log.wtf once Process.isSupplemental is ready.
+            Log.e(TAG, "TrafficStats not initialized, uid=" + Binder.getCallingUid());
+            return;
+        }
+        sStatsService = statsManager.getBinder();
+    }
+
+    /**
+     * Attach the socket tagger implementation to the current process, to
+     * get notified when a socket's {@link FileDescriptor} is assigned to
+     * a thread. See {@link SocketTagger#set(SocketTagger)}.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    public static void attachSocketTagger() {
+        dalvik.system.SocketTagger.set(new SocketTagger());
+    }
+
+    private static class SocketTagger extends dalvik.system.SocketTagger {
+
+        // TODO: set to false
+        private static final boolean LOGD = true;
+
+        SocketTagger() {
+        }
+
+        @Override
+        public void tag(FileDescriptor fd) throws SocketException {
+            final UidTag tagInfo = sThreadUidTag.get();
+            if (LOGD) {
+                Log.d(TAG, "tagSocket(" + fd.getInt$() + ") with statsTag=0x"
+                        + Integer.toHexString(tagInfo.tag) + ", statsUid=" + tagInfo.uid);
+            }
+            if (tagInfo.tag == -1) {
+                StrictMode.noteUntaggedSocket();
+            }
+
+            if (tagInfo.tag == -1 && tagInfo.uid == -1) return;
+            final int errno = native_tagSocketFd(fd, tagInfo.tag, tagInfo.uid);
+            if (errno < 0) {
+                Log.i(TAG, "tagSocketFd(" + fd.getInt$() + ", "
+                        + tagInfo.tag + ", "
+                        + tagInfo.uid + ") failed with errno" + errno);
+            }
+        }
+
+        @Override
+        public void untag(FileDescriptor fd) throws SocketException {
+            if (LOGD) {
+                Log.i(TAG, "untagSocket(" + fd.getInt$() + ")");
+            }
+
+            final UidTag tagInfo = sThreadUidTag.get();
+            if (tagInfo.tag == -1 && tagInfo.uid == -1) return;
+
+            final int errno = native_untagSocketFd(fd);
+            if (errno < 0) {
+                Log.w(TAG, "untagSocket(" + fd.getInt$() + ") failed with errno " + errno);
+            }
+        }
+    }
+
+    private static native int native_tagSocketFd(FileDescriptor fd, int tag, int uid);
+    private static native int native_untagSocketFd(FileDescriptor fd);
+
+    private static class UidTag {
+        public int tag = -1;
+        public int uid = -1;
+    }
+
+    private static ThreadLocal<UidTag> sThreadUidTag = new ThreadLocal<UidTag>() {
+        @Override
+        protected UidTag initialValue() {
+            return new UidTag();
+        }
+    };
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     * <p>
+     * Tags between {@code 0xFFFFFF00} and {@code 0xFFFFFFFF} are reserved and
+     * used internally by system services like {@link DownloadManager} when
+     * performing traffic on behalf of an application.
+     *
+     * @see #clearThreadStatsTag()
+     */
+    public static void setThreadStatsTag(int tag) {
+        getAndSetThreadStatsTag(tag);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     * <p>
+     * Tags between {@code 0xFFFFFF00} and {@code 0xFFFFFFFF} are reserved and
+     * used internally by system services like {@link DownloadManager} when
+     * performing traffic on behalf of an application.
+     *
+     * @return the current tag for the calling thread, which can be used to
+     *         restore any existing values after a nested operation is finished
+     */
+    public static int getAndSetThreadStatsTag(int tag) {
+        final int old = sThreadUidTag.get().tag;
+        sThreadUidTag.get().tag = tag;
+        return old;
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all backup-related traffic.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagBackup() {
+        setThreadStatsTag(TAG_SYSTEM_BACKUP);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all restore-related traffic.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagRestore() {
+        setThreadStatsTag(TAG_SYSTEM_RESTORE);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all code (typically APKs) downloaded by an app store on
+     * behalf of the app, such as updates.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagApp() {
+        setThreadStatsTag(TAG_SYSTEM_APP);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all download provider traffic.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagDownload() {
+        setThreadStatsTag(TAG_SYSTEM_DOWNLOAD);
+    }
+
+    /**
+     * Get the active tag used when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * {@link #tagSocket(Socket)}.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static int getThreadStatsTag() {
+        return sThreadUidTag.get().tag;
+    }
+
+    /**
+     * Clear any active tag set to account {@link Socket} traffic originating
+     * from the current thread.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void clearThreadStatsTag() {
+        sThreadUidTag.get().tag = -1;
+    }
+
+    /**
+     * Set specific UID to use when accounting {@link Socket} traffic
+     * originating from the current thread. Designed for use when performing an
+     * operation on behalf of another application, or when another application
+     * is performing operations on your behalf.
+     * <p>
+     * Any app can <em>accept</em> blame for traffic performed on a socket
+     * originally created by another app by calling this method with the
+     * {@link android.system.Os#getuid()} value. However, only apps holding the
+     * {@code android.Manifest.permission#UPDATE_DEVICE_STATS} permission may
+     * <em>assign</em> blame to another UIDs.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     */
+    @SuppressLint("RequiresPermission")
+    public static void setThreadStatsUid(int uid) {
+        sThreadUidTag.get().uid = uid;
+    }
+
+    /**
+     * Get the active UID used when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * {@link #tagSocket(Socket)}.
+     *
+     * @see #setThreadStatsUid(int)
+     */
+    public static int getThreadStatsUid() {
+        return sThreadUidTag.get().uid;
+    }
+
+    /**
+     * Set specific UID to use when accounting {@link Socket} traffic
+     * originating from the current thread as the calling UID. Designed for use
+     * when another application is performing operations on your behalf.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     *
+     * @removed
+     * @deprecated use {@link #setThreadStatsUid(int)} instead.
+     */
+    @Deprecated
+    public static void setThreadStatsUidSelf() {
+        setThreadStatsUid(android.os.Process.myUid());
+    }
+
+    /**
+     * Clear any active UID set to account {@link Socket} traffic originating
+     * from the current thread.
+     *
+     * @see #setThreadStatsUid(int)
+     */
+    @SuppressLint("RequiresPermission")
+    public static void clearThreadStatsUid() {
+        setThreadStatsUid(-1);
+    }
+
+    /**
+     * Tag the given {@link Socket} with any statistics parameters active for
+     * the current thread. Subsequent calls always replace any existing
+     * parameters. When finished, call {@link #untagSocket(Socket)} to remove
+     * statistics parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagSocket(Socket socket) throws SocketException {
+        SocketTagger.get().tag(socket);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link Socket}.
+     * <p>
+     * In Android 8.1 (API level 27) and lower, a socket is automatically
+     * untagged when it's sent to another process using binder IPC with a
+     * {@code ParcelFileDescriptor} container. In Android 9.0 (API level 28)
+     * and higher, the socket tag is kept when the socket is sent to another
+     * process using binder IPC. You can mimic the previous behavior by
+     * calling {@code untagSocket()} before sending the socket to another
+     * process.
+     */
+    public static void untagSocket(Socket socket) throws SocketException {
+        SocketTagger.get().untag(socket);
+    }
+
+    /**
+     * Tag the given {@link DatagramSocket} with any statistics parameters
+     * active for the current thread. Subsequent calls always replace any
+     * existing parameters. When finished, call
+     * {@link #untagDatagramSocket(DatagramSocket)} to remove statistics
+     * parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagDatagramSocket(DatagramSocket socket) throws SocketException {
+        SocketTagger.get().tag(socket);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link DatagramSocket}.
+     */
+    public static void untagDatagramSocket(DatagramSocket socket) throws SocketException {
+        SocketTagger.get().untag(socket);
+    }
+
+    /**
+     * Tag the given {@link FileDescriptor} socket with any statistics
+     * parameters active for the current thread. Subsequent calls always replace
+     * any existing parameters. When finished, call
+     * {@link #untagFileDescriptor(FileDescriptor)} to remove statistics
+     * parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagFileDescriptor(FileDescriptor fd) throws IOException {
+        SocketTagger.get().tag(fd);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link FileDescriptor}
+     * socket.
+     */
+    public static void untagFileDescriptor(FileDescriptor fd) throws IOException {
+        SocketTagger.get().untag(fd);
+    }
+
+    /**
+     * Start profiling data usage for current UID. Only one profiling session
+     * can be active at a time.
+     *
+     * @hide
+     */
+    public static void startDataProfiling(Context context) {
+        synchronized (sProfilingLock) {
+            if (sActiveProfilingStart != null) {
+                throw new IllegalStateException("already profiling data");
+            }
+
+            // take snapshot in time; we calculate delta later
+            sActiveProfilingStart = getDataLayerSnapshotForUid(context);
+        }
+    }
+
+    /**
+     * Stop profiling data usage for current UID.
+     *
+     * @return Detailed {@link NetworkStats} of data that occurred since last
+     *         {@link #startDataProfiling(Context)} call.
+     * @hide
+     */
+    public static NetworkStats stopDataProfiling(Context context) {
+        synchronized (sProfilingLock) {
+            if (sActiveProfilingStart == null) {
+                throw new IllegalStateException("not profiling data");
+            }
+
+            // subtract starting values and return delta
+            final NetworkStats profilingStop = getDataLayerSnapshotForUid(context);
+            final NetworkStats profilingDelta = NetworkStats.subtract(
+                    profilingStop, sActiveProfilingStart, null, null);
+            sActiveProfilingStart = null;
+            return profilingDelta;
+        }
+    }
+
+    /**
+     * Increment count of network operations performed under the accounting tag
+     * currently active on the calling thread. This can be used to derive
+     * bytes-per-operation.
+     *
+     * @param operationCount Number of operations to increment count by.
+     */
+    public static void incrementOperationCount(int operationCount) {
+        final int tag = getThreadStatsTag();
+        incrementOperationCount(tag, operationCount);
+    }
+
+    /**
+     * Increment count of network operations performed under the given
+     * accounting tag. This can be used to derive bytes-per-operation.
+     *
+     * @param tag Accounting tag used in {@link #setThreadStatsTag(int)}.
+     * @param operationCount Number of operations to increment count by.
+     */
+    public static void incrementOperationCount(int tag, int operationCount) {
+        final int uid = android.os.Process.myUid();
+        try {
+            getStatsService().incrementOperationCount(uid, tag, operationCount);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    public static void closeQuietly(INetworkStatsSession session) {
+        // TODO: move to NetworkStatsService once it exists
+        if (session != null) {
+            try {
+                session.close();
+            } catch (RuntimeException rethrown) {
+                throw rethrown;
+            } catch (Exception ignored) {
+            }
+        }
+    }
+
+    private static long addIfSupported(long stat) {
+        return (stat == UNSUPPORTED) ? 0 : stat;
+    }
+
+    /**
+     * Return number of packets transmitted across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileTxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getTxPackets(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of packets received across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileRxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getRxPackets(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of bytes transmitted across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileTxBytes() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getTxBytes(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of bytes received across mobile networks since device boot.
+     * Counts packets across all mobile network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileRxBytes() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getRxBytes(iface));
+        }
+        return total;
+    }
+
+    /** {@hide} */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static long getMobileTcpRxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            long stat = UNSUPPORTED;
+            try {
+                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_RX_PACKETS);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            total += addIfSupported(stat);
+        }
+        return total;
+    }
+
+    /** {@hide} */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static long getMobileTcpTxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            long stat = UNSUPPORTED;
+            try {
+                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_TX_PACKETS);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            total += addIfSupported(stat);
+        }
+        return total;
+    }
+
+    /**
+     * Return the number of packets transmitted on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP and
+     * UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of transmitted packets.
+     */
+    public static long getTxPackets(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of packets received on the specified interface since the interface was
+     * created. Statistics are measured at the network layer, so both TCP
+     * and UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of received packets.
+     */
+    public static long getRxPackets(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of bytes transmitted on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP and
+     * UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of transmitted bytes.
+     */
+    public static long getTxBytes(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of bytes received on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP
+     * and UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of received bytes.
+     */
+    public static long getRxBytes(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackTxPackets() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackRxPackets() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackTxBytes() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackRxBytes() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets transmitted since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalTxPackets() {
+        try {
+            return getStatsService().getTotalStats(TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets received since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalRxPackets() {
+        try {
+            return getStatsService().getTotalStats(TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes transmitted since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalTxBytes() {
+        try {
+            return getStatsService().getTotalStats(TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes received since device boot. Counts packets across
+     * all network interfaces, and always increases monotonically since device
+     * boot. Statistics are measured at the network layer, so they include both
+     * TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalRxBytes() {
+        try {
+            return getStatsService().getTotalStats(TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes transmitted by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidTxBytes(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes received by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidRxBytes(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets transmitted by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidTxPackets(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets received by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidRxPackets(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxBytes(int)
+     */
+    @Deprecated
+    public static long getUidTcpTxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxBytes(int)
+     */
+    @Deprecated
+    public static long getUidTcpRxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxBytes(int)
+     */
+    @Deprecated
+    public static long getUidUdpTxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxBytes(int)
+     */
+    @Deprecated
+    public static long getUidUdpRxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxPackets(int)
+     */
+    @Deprecated
+    public static long getUidTcpTxSegments(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxPackets(int)
+     */
+    @Deprecated
+    public static long getUidTcpRxSegments(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxPackets(int)
+     */
+    @Deprecated
+    public static long getUidUdpTxPackets(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxPackets(int)
+     */
+    @Deprecated
+    public static long getUidUdpRxPackets(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * Return detailed {@link NetworkStats} for the current UID. Requires no
+     * special permission.
+     */
+    private static NetworkStats getDataLayerSnapshotForUid(Context context) {
+        // TODO: take snapshot locally, since proc file is now visible
+        final int uid = android.os.Process.myUid();
+        try {
+            return getStatsService().getDataLayerSnapshotForUid(uid);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return set of any ifaces associated with mobile networks since boot.
+     * Interfaces are never removed from this list, so counters should always be
+     * monotonic.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 130143562)
+    private static String[] getMobileIfaces() {
+        try {
+            return getStatsService().getMobileIfaces();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    // NOTE: keep these in sync with {@code com_android_server_net_NetworkStatsService.cpp}.
+    /** {@hide} */
+    public static final int TYPE_RX_BYTES = 0;
+    /** {@hide} */
+    public static final int TYPE_RX_PACKETS = 1;
+    /** {@hide} */
+    public static final int TYPE_TX_BYTES = 2;
+    /** {@hide} */
+    public static final int TYPE_TX_PACKETS = 3;
+    /** {@hide} */
+    public static final int TYPE_TCP_RX_PACKETS = 4;
+    /** {@hide} */
+    public static final int TYPE_TCP_TX_PACKETS = 5;
+}
diff --git a/framework-t/src/android/net/UnderlyingNetworkInfo.aidl b/framework-t/src/android/net/UnderlyingNetworkInfo.aidl
new file mode 100644
index 0000000..a56f2f4
--- /dev/null
+++ b/framework-t/src/android/net/UnderlyingNetworkInfo.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable UnderlyingNetworkInfo;
diff --git a/framework-t/src/android/net/UnderlyingNetworkInfo.java b/framework-t/src/android/net/UnderlyingNetworkInfo.java
new file mode 100644
index 0000000..33f9375
--- /dev/null
+++ b/framework-t/src/android/net/UnderlyingNetworkInfo.java
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A lightweight container used to carry information on the networks that underly a given
+ * virtual network.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class UnderlyingNetworkInfo implements Parcelable {
+    /** The owner of this network. */
+    private final int mOwnerUid;
+
+    /** The interface name of this network. */
+    @NonNull
+    private final String mIface;
+
+    /** The names of the interfaces underlying this network. */
+    @NonNull
+    private final List<String> mUnderlyingIfaces;
+
+    public UnderlyingNetworkInfo(int ownerUid, @NonNull String iface,
+            @NonNull List<String> underlyingIfaces) {
+        Objects.requireNonNull(iface);
+        Objects.requireNonNull(underlyingIfaces);
+        mOwnerUid = ownerUid;
+        mIface = iface;
+        mUnderlyingIfaces = Collections.unmodifiableList(new ArrayList<>(underlyingIfaces));
+    }
+
+    private UnderlyingNetworkInfo(@NonNull Parcel in) {
+        mOwnerUid = in.readInt();
+        mIface = in.readString();
+        List<String> underlyingIfaces = new ArrayList<>();
+        in.readList(underlyingIfaces, null /*classLoader*/);
+        mUnderlyingIfaces = Collections.unmodifiableList(underlyingIfaces);
+    }
+
+    /** Get the owner of this network. */
+    public int getOwnerUid() {
+        return mOwnerUid;
+    }
+
+    /** Get the interface name of this network. */
+    @NonNull
+    public String getInterface() {
+        return mIface;
+    }
+
+    /** Get the names of the interfaces underlying this network. */
+    @NonNull
+    public List<String> getUnderlyingInterfaces() {
+        return mUnderlyingIfaces;
+    }
+
+    @Override
+    public String toString() {
+        return "UnderlyingNetworkInfo{"
+                + "ownerUid=" + mOwnerUid
+                + ", iface='" + mIface + '\''
+                + ", underlyingIfaces='" + mUnderlyingIfaces.toString() + '\''
+                + '}';
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mOwnerUid);
+        dest.writeString(mIface);
+        dest.writeList(mUnderlyingIfaces);
+    }
+
+    @NonNull
+    public static final Parcelable.Creator<UnderlyingNetworkInfo> CREATOR =
+            new Parcelable.Creator<UnderlyingNetworkInfo>() {
+        @NonNull
+        @Override
+        public UnderlyingNetworkInfo createFromParcel(@NonNull Parcel in) {
+            return new UnderlyingNetworkInfo(in);
+        }
+
+        @NonNull
+        @Override
+        public UnderlyingNetworkInfo[] newArray(int size) {
+            return new UnderlyingNetworkInfo[size];
+        }
+    };
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof UnderlyingNetworkInfo)) return false;
+        final UnderlyingNetworkInfo that = (UnderlyingNetworkInfo) o;
+        return mOwnerUid == that.getOwnerUid()
+                && Objects.equals(mIface, that.getInterface())
+                && Objects.equals(mUnderlyingIfaces, that.getUnderlyingInterfaces());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mOwnerUid, mIface, mUnderlyingIfaces);
+    }
+}
diff --git a/framework-t/src/android/net/netstats/IUsageCallback.aidl b/framework-t/src/android/net/netstats/IUsageCallback.aidl
new file mode 100644
index 0000000..4e8a5b2
--- /dev/null
+++ b/framework-t/src/android/net/netstats/IUsageCallback.aidl
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats;
+
+import android.net.DataUsageRequest;
+
+/**
+ * Interface for NetworkStatsService to notify events to the callers of registerUsageCallback.
+ *
+ * @hide
+ */
+oneway interface IUsageCallback {
+    void onThresholdReached(in DataUsageRequest request);
+    void onCallbackReleased(in DataUsageRequest request);
+}
diff --git a/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl b/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl
new file mode 100644
index 0000000..74c3ba4
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+/**
+ * Interface for NetworkStatsService to query network statistics and set data limits.
+ *
+ * @hide
+ */
+oneway interface INetworkStatsProvider {
+    void onRequestStatsUpdate(int token);
+    void onSetAlert(long quotaBytes);
+    void onSetWarningAndLimit(String iface, long warningBytes, long limitBytes);
+}
diff --git a/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl b/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl
new file mode 100644
index 0000000..01ff02d
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+import android.net.NetworkStats;
+
+/**
+ * Interface for implementor of {@link INetworkStatsProviderCallback} to push events
+ * such as network statistics update or notify limit reached.
+ * @hide
+ */
+oneway interface INetworkStatsProviderCallback {
+    void notifyStatsUpdated(int token, in NetworkStats ifaceStats, in NetworkStats uidStats);
+    void notifyAlertReached();
+    void notifyWarningReached();
+    void notifyLimitReached();
+    void unregister();
+}
diff --git a/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java b/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java
new file mode 100644
index 0000000..d37a53d
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.net.NetworkStats;
+import android.os.RemoteException;
+
+/**
+ * A base class that allows external modules to implement a custom network statistics provider.
+ * @hide
+ */
+@SystemApi
+public abstract class NetworkStatsProvider {
+    /**
+     * A value used by {@link #onSetLimit}, {@link #onSetAlert} and {@link #onSetWarningAndLimit}
+     * indicates there is no limit.
+     */
+    public static final int QUOTA_UNLIMITED = -1;
+
+    @NonNull private final INetworkStatsProvider mProviderBinder =
+            new INetworkStatsProvider.Stub() {
+
+        @Override
+        public void onRequestStatsUpdate(int token) {
+            NetworkStatsProvider.this.onRequestStatsUpdate(token);
+        }
+
+        @Override
+        public void onSetAlert(long quotaBytes) {
+            NetworkStatsProvider.this.onSetAlert(quotaBytes);
+        }
+
+        @Override
+        public void onSetWarningAndLimit(String iface, long warningBytes, long limitBytes) {
+            NetworkStatsProvider.this.onSetWarningAndLimit(iface, warningBytes, limitBytes);
+        }
+    };
+
+    // The binder given by the service when successfully registering. Only null before registering,
+    // never null once non-null.
+    @Nullable
+    private INetworkStatsProviderCallback mProviderCbBinder;
+
+    /**
+     * Return the binder invoked by the service and redirect function calls to the overridden
+     * methods.
+     * @hide
+     */
+    @NonNull
+    public INetworkStatsProvider getProviderBinder() {
+        return mProviderBinder;
+    }
+
+    /**
+     * Store the binder that was returned by the service when successfully registering. Note that
+     * the provider cannot be re-registered. Hence this method can only be called once per provider.
+     *
+     * @hide
+     */
+    public void setProviderCallbackBinder(@NonNull INetworkStatsProviderCallback binder) {
+        if (mProviderCbBinder != null) {
+            throw new IllegalArgumentException("provider is already registered");
+        }
+        mProviderCbBinder = binder;
+    }
+
+    /**
+     * Get the binder that was returned by the service when successfully registering. Or null if the
+     * provider was never registered.
+     *
+     * @hide
+     */
+    @Nullable
+    public INetworkStatsProviderCallback getProviderCallbackBinder() {
+        return mProviderCbBinder;
+    }
+
+    /**
+     * Get the binder that was returned by the service when successfully registering. Throw an
+     * {@link IllegalStateException} if the provider is not registered.
+     *
+     * @hide
+     */
+    @NonNull
+    public INetworkStatsProviderCallback getProviderCallbackBinderOrThrow() {
+        if (mProviderCbBinder == null) {
+            throw new IllegalStateException("the provider is not registered");
+        }
+        return mProviderCbBinder;
+    }
+
+    /**
+     * Notify the system of new network statistics.
+     *
+     * Send the network statistics recorded since the last call to {@link #notifyStatsUpdated}. Must
+     * be called as soon as possible after {@link NetworkStatsProvider#onRequestStatsUpdate(int)}
+     * being called. Responding later increases the probability stats will be dropped. The
+     * provider can also call this whenever it wants to reports new stats for any reason.
+     * Note that the system will not necessarily immediately propagate the statistics to
+     * reflect the update.
+     *
+     * @param token the token under which these stats were gathered. Providers can call this method
+     *              with the current token as often as they want, until the token changes.
+     *              {@see NetworkStatsProvider#onRequestStatsUpdate()}
+     * @param ifaceStats the {@link NetworkStats} per interface to be reported.
+     *                   The provider should not include any traffic that is already counted by
+     *                   kernel interface counters.
+     * @param uidStats the same stats as above, but counts {@link NetworkStats}
+     *                 per uid.
+     */
+    public void notifyStatsUpdated(int token, @NonNull NetworkStats ifaceStats,
+            @NonNull NetworkStats uidStats) {
+        try {
+            getProviderCallbackBinderOrThrow().notifyStatsUpdated(token, ifaceStats, uidStats);
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the quota set by {@code onSetAlert} has been reached.
+     */
+    public void notifyAlertReached() {
+        try {
+            getProviderCallbackBinderOrThrow().notifyAlertReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the warning set by {@link #onSetWarningAndLimit} has been reached.
+     */
+    public void notifyWarningReached() {
+        try {
+            // Reuse the code path to notify warning reached with limit reached
+            // since framework handles them in the same way.
+            getProviderCallbackBinderOrThrow().notifyWarningReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the limit set by {@link #onSetLimit} or limit set by
+     * {@link #onSetWarningAndLimit} has been reached.
+     */
+    public void notifyLimitReached() {
+        try {
+            getProviderCallbackBinderOrThrow().notifyLimitReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Called by {@code NetworkStatsService} when it requires to know updated stats.
+     * The provider MUST respond by calling {@link #notifyStatsUpdated} as soon as possible.
+     * Responding later increases the probability stats will be dropped. Memory allowing, the
+     * system will try to take stats into account up to one minute after calling
+     * {@link #onRequestStatsUpdate}.
+     *
+     * @param token a positive number identifying the new state of the system under which
+     *              {@link NetworkStats} have to be gathered from now on. When this is called,
+     *              custom implementations of providers MUST tally and report the latest stats with
+     *              the previous token, under which stats were being gathered so far.
+     */
+    public abstract void onRequestStatsUpdate(int token);
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the interface quota for the specified
+     * upstream interface. When this is called, the custom implementation should block all egress
+     * packets on the {@code iface} associated with the provider when {@code quotaBytes} bytes have
+     * been reached, and MUST respond to it by calling
+     * {@link NetworkStatsProvider#notifyLimitReached()}.
+     *
+     * @param iface the interface requiring the operation.
+     * @param quotaBytes the quota defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no limit.
+     */
+    public abstract void onSetLimit(@NonNull String iface, long quotaBytes);
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the interface quotas for the specified
+     * upstream interface. If a provider implements {@link #onSetWarningAndLimit}, the system
+     * will not call {@link #onSetLimit}. When this method is called, the implementation
+     * should behave as follows:
+     *   1. If {@code warningBytes} is reached on {@code iface}, block all further traffic on
+     *      {@code iface} and call {@link NetworkStatsProvider@notifyWarningReached()}.
+     *   2. If {@code limitBytes} is reached on {@code iface}, block all further traffic on
+     *   {@code iface} and call {@link NetworkStatsProvider#notifyLimitReached()}.
+     *
+     * @param iface the interface requiring the operation.
+     * @param warningBytes the warning defined as the number of bytes, starting from zero and
+     *                     counting from now. A value of {@link #QUOTA_UNLIMITED} indicates
+     *                     there is no warning.
+     * @param limitBytes the limit defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no limit.
+     */
+    public void onSetWarningAndLimit(@NonNull String iface, long warningBytes, long limitBytes) {
+        // Backward compatibility for those who didn't override this function.
+        onSetLimit(iface, limitBytes);
+    }
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the alert bytes. Custom implementations
+     * MUST call {@link NetworkStatsProvider#notifyAlertReached()} when {@code quotaBytes} bytes
+     * have been reached. Unlike {@link #onSetLimit(String, long)}, the custom implementation should
+     * not block all egress packets.
+     *
+     * @param quotaBytes the quota defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no alert.
+     */
+    public abstract void onSetAlert(long quotaBytes);
+}
diff --git a/framework-t/src/android/net/nsd/INsdManager.aidl b/framework-t/src/android/net/nsd/INsdManager.aidl
new file mode 100644
index 0000000..89e9cdb
--- /dev/null
+++ b/framework-t/src/android/net/nsd/INsdManager.aidl
@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2021, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.nsd;
+
+import android.net.nsd.INsdManagerCallback;
+import android.net.nsd.INsdServiceConnector;
+import android.os.Messenger;
+
+/**
+ * Interface that NsdService implements to connect NsdManager clients.
+ *
+ * {@hide}
+ */
+interface INsdManager {
+    INsdServiceConnector connect(INsdManagerCallback cb);
+}
diff --git a/framework-t/src/android/net/nsd/INsdManagerCallback.aidl b/framework-t/src/android/net/nsd/INsdManagerCallback.aidl
new file mode 100644
index 0000000..1a262ec
--- /dev/null
+++ b/framework-t/src/android/net/nsd/INsdManagerCallback.aidl
@@ -0,0 +1,39 @@
+/**
+ * Copyright (c) 2021, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.nsd;
+
+import android.os.Messenger;
+import android.net.nsd.NsdServiceInfo;
+
+/**
+ * Callbacks from NsdService to NsdManager
+ * @hide
+ */
+oneway interface INsdManagerCallback {
+    void onDiscoverServicesStarted(int listenerKey, in NsdServiceInfo info);
+    void onDiscoverServicesFailed(int listenerKey, int error);
+    void onServiceFound(int listenerKey, in NsdServiceInfo info);
+    void onServiceLost(int listenerKey, in NsdServiceInfo info);
+    void onStopDiscoveryFailed(int listenerKey, int error);
+    void onStopDiscoverySucceeded(int listenerKey);
+    void onRegisterServiceFailed(int listenerKey, int error);
+    void onRegisterServiceSucceeded(int listenerKey, in NsdServiceInfo info);
+    void onUnregisterServiceFailed(int listenerKey, int error);
+    void onUnregisterServiceSucceeded(int listenerKey);
+    void onResolveServiceFailed(int listenerKey, int error);
+    void onResolveServiceSucceeded(int listenerKey, in NsdServiceInfo info);
+}
diff --git a/framework-t/src/android/net/nsd/INsdServiceConnector.aidl b/framework-t/src/android/net/nsd/INsdServiceConnector.aidl
new file mode 100644
index 0000000..b06ae55
--- /dev/null
+++ b/framework-t/src/android/net/nsd/INsdServiceConnector.aidl
@@ -0,0 +1,35 @@
+/**
+ * Copyright (c) 2021, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.nsd;
+
+import android.net.nsd.INsdManagerCallback;
+import android.net.nsd.NsdServiceInfo;
+import android.os.Messenger;
+
+/**
+ * Interface that NsdService implements for each NsdManager client.
+ *
+ * {@hide}
+ */
+interface INsdServiceConnector {
+    void registerService(int listenerKey, in NsdServiceInfo serviceInfo);
+    void unregisterService(int listenerKey);
+    void discoverServices(int listenerKey, in NsdServiceInfo serviceInfo);
+    void stopDiscovery(int listenerKey);
+    void resolveService(int listenerKey, in NsdServiceInfo serviceInfo);
+    void startDaemon();
+}
\ No newline at end of file
diff --git a/framework-t/src/android/net/nsd/NsdManager.java b/framework-t/src/android/net/nsd/NsdManager.java
new file mode 100644
index 0000000..209f372
--- /dev/null
+++ b/framework-t/src/android/net/nsd/NsdManager.java
@@ -0,0 +1,1083 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.nsd;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
+import android.annotation.SdkConstant;
+import android.annotation.SdkConstant.SdkConstantType;
+import android.annotation.SystemService;
+import android.app.compat.CompatChanges;
+import android.compat.annotation.ChangeId;
+import android.compat.annotation.EnabledSince;
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.ConnectivityManager.NetworkCallback;
+import android.net.Network;
+import android.net.NetworkRequest;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Looper;
+import android.os.Message;
+import android.os.RemoteException;
+import android.text.TextUtils;
+import android.util.ArrayMap;
+import android.util.ArraySet;
+import android.util.Log;
+import android.util.SparseArray;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.util.Objects;
+import java.util.concurrent.Executor;
+
+/**
+ * The Network Service Discovery Manager class provides the API to discover services
+ * on a network. As an example, if device A and device B are connected over a Wi-Fi
+ * network, a game registered on device A can be discovered by a game on device
+ * B. Another example use case is an application discovering printers on the network.
+ *
+ * <p> The API currently supports DNS based service discovery and discovery is currently
+ * limited to a local network over Multicast DNS. DNS service discovery is described at
+ * http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt
+ *
+ * <p> The API is asynchronous, and responses to requests from an application are on listener
+ * callbacks on a separate internal thread.
+ *
+ * <p> There are three main operations the API supports - registration, discovery and resolution.
+ * <pre>
+ *                          Application start
+ *                                 |
+ *                                 |
+ *                                 |                  onServiceRegistered()
+ *                     Register any local services  /
+ *                      to be advertised with       \
+ *                       registerService()            onRegistrationFailed()
+ *                                 |
+ *                                 |
+ *                          discoverServices()
+ *                                 |
+ *                      Maintain a list to track
+ *                        discovered services
+ *                                 |
+ *                                 |--------->
+ *                                 |          |
+ *                                 |      onServiceFound()
+ *                                 |          |
+ *                                 |     add service to list
+ *                                 |          |
+ *                                 |<----------
+ *                                 |
+ *                                 |--------->
+ *                                 |          |
+ *                                 |      onServiceLost()
+ *                                 |          |
+ *                                 |   remove service from list
+ *                                 |          |
+ *                                 |<----------
+ *                                 |
+ *                                 |
+ *                                 | Connect to a service
+ *                                 | from list ?
+ *                                 |
+ *                          resolveService()
+ *                                 |
+ *                         onServiceResolved()
+ *                                 |
+ *                     Establish connection to service
+ *                     with the host and port information
+ *
+ * </pre>
+ * An application that needs to advertise itself over a network for other applications to
+ * discover it can do so with a call to {@link #registerService}. If Example is a http based
+ * application that can provide HTML data to peer services, it can register a name "Example"
+ * with service type "_http._tcp". A successful registration is notified with a callback to
+ * {@link RegistrationListener#onServiceRegistered} and a failure to register is notified
+ * over {@link RegistrationListener#onRegistrationFailed}
+ *
+ * <p> A peer application looking for http services can initiate a discovery for "_http._tcp"
+ * with a call to {@link #discoverServices}. A service found is notified with a callback
+ * to {@link DiscoveryListener#onServiceFound} and a service lost is notified on
+ * {@link DiscoveryListener#onServiceLost}.
+ *
+ * <p> Once the peer application discovers the "Example" http service, and either needs to read the
+ * attributes of the service or wants to receive data from the "Example" application, it can
+ * initiate a resolve with {@link #resolveService} to resolve the attributes, host, and port
+ * details. A successful resolve is notified on {@link ResolveListener#onServiceResolved} and a
+ * failure is notified on {@link ResolveListener#onResolveFailed}.
+ *
+ * Applications can reserve for a service type at
+ * http://www.iana.org/form/ports-service. Existing services can be found at
+ * http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml
+ *
+ * {@see NsdServiceInfo}
+ */
+@SystemService(Context.NSD_SERVICE)
+public final class NsdManager {
+    private static final String TAG = NsdManager.class.getSimpleName();
+    private static final boolean DBG = false;
+
+    /**
+     * When enabled, apps targeting < Android 12 are considered legacy for
+     * the NSD native daemon.
+     * The platform will only keep the daemon running as long as there are
+     * any legacy apps connected.
+     *
+     * After Android 12, directly communicate with native daemon might not
+     * work since the native damon won't always stay alive.
+     * Use the NSD APIs from NsdManager as the replacement is recommended.
+     * An another alternative could be bundling your own mdns solutions instead of
+     * depending on the system mdns native daemon.
+     *
+     * @hide
+     */
+    @ChangeId
+    @EnabledSince(targetSdkVersion = android.os.Build.VERSION_CODES.S)
+    public static final long RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS = 191844585L;
+
+    /**
+     * Broadcast intent action to indicate whether network service discovery is
+     * enabled or disabled. An extra {@link #EXTRA_NSD_STATE} provides the state
+     * information as int.
+     *
+     * @see #EXTRA_NSD_STATE
+     */
+    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
+    public static final String ACTION_NSD_STATE_CHANGED = "android.net.nsd.STATE_CHANGED";
+
+    /**
+     * The lookup key for an int that indicates whether network service discovery is enabled
+     * or disabled. Retrieve it with {@link android.content.Intent#getIntExtra(String,int)}.
+     *
+     * @see #NSD_STATE_DISABLED
+     * @see #NSD_STATE_ENABLED
+     */
+    public static final String EXTRA_NSD_STATE = "nsd_state";
+
+    /**
+     * Network service discovery is disabled
+     *
+     * @see #ACTION_NSD_STATE_CHANGED
+     */
+    public static final int NSD_STATE_DISABLED = 1;
+
+    /**
+     * Network service discovery is enabled
+     *
+     * @see #ACTION_NSD_STATE_CHANGED
+     */
+    public static final int NSD_STATE_ENABLED = 2;
+
+    /** @hide */
+    public static final int DISCOVER_SERVICES                       = 1;
+    /** @hide */
+    public static final int DISCOVER_SERVICES_STARTED               = 2;
+    /** @hide */
+    public static final int DISCOVER_SERVICES_FAILED                = 3;
+    /** @hide */
+    public static final int SERVICE_FOUND                           = 4;
+    /** @hide */
+    public static final int SERVICE_LOST                            = 5;
+
+    /** @hide */
+    public static final int STOP_DISCOVERY                          = 6;
+    /** @hide */
+    public static final int STOP_DISCOVERY_FAILED                   = 7;
+    /** @hide */
+    public static final int STOP_DISCOVERY_SUCCEEDED                = 8;
+
+    /** @hide */
+    public static final int REGISTER_SERVICE                        = 9;
+    /** @hide */
+    public static final int REGISTER_SERVICE_FAILED                 = 10;
+    /** @hide */
+    public static final int REGISTER_SERVICE_SUCCEEDED              = 11;
+
+    /** @hide */
+    public static final int UNREGISTER_SERVICE                      = 12;
+    /** @hide */
+    public static final int UNREGISTER_SERVICE_FAILED               = 13;
+    /** @hide */
+    public static final int UNREGISTER_SERVICE_SUCCEEDED            = 14;
+
+    /** @hide */
+    public static final int RESOLVE_SERVICE                         = 15;
+    /** @hide */
+    public static final int RESOLVE_SERVICE_FAILED                  = 16;
+    /** @hide */
+    public static final int RESOLVE_SERVICE_SUCCEEDED               = 17;
+
+    /** @hide */
+    public static final int DAEMON_CLEANUP                          = 18;
+
+    /** @hide */
+    public static final int DAEMON_STARTUP                          = 19;
+
+    /** @hide */
+    public static final int ENABLE                                  = 20;
+    /** @hide */
+    public static final int DISABLE                                 = 21;
+
+    /** @hide */
+    public static final int NATIVE_DAEMON_EVENT                     = 22;
+
+    /** @hide */
+    public static final int REGISTER_CLIENT                         = 23;
+    /** @hide */
+    public static final int UNREGISTER_CLIENT                       = 24;
+
+    /** Dns based service discovery protocol */
+    public static final int PROTOCOL_DNS_SD = 0x0001;
+
+    private static final SparseArray<String> EVENT_NAMES = new SparseArray<>();
+    static {
+        EVENT_NAMES.put(DISCOVER_SERVICES, "DISCOVER_SERVICES");
+        EVENT_NAMES.put(DISCOVER_SERVICES_STARTED, "DISCOVER_SERVICES_STARTED");
+        EVENT_NAMES.put(DISCOVER_SERVICES_FAILED, "DISCOVER_SERVICES_FAILED");
+        EVENT_NAMES.put(SERVICE_FOUND, "SERVICE_FOUND");
+        EVENT_NAMES.put(SERVICE_LOST, "SERVICE_LOST");
+        EVENT_NAMES.put(STOP_DISCOVERY, "STOP_DISCOVERY");
+        EVENT_NAMES.put(STOP_DISCOVERY_FAILED, "STOP_DISCOVERY_FAILED");
+        EVENT_NAMES.put(STOP_DISCOVERY_SUCCEEDED, "STOP_DISCOVERY_SUCCEEDED");
+        EVENT_NAMES.put(REGISTER_SERVICE, "REGISTER_SERVICE");
+        EVENT_NAMES.put(REGISTER_SERVICE_FAILED, "REGISTER_SERVICE_FAILED");
+        EVENT_NAMES.put(REGISTER_SERVICE_SUCCEEDED, "REGISTER_SERVICE_SUCCEEDED");
+        EVENT_NAMES.put(UNREGISTER_SERVICE, "UNREGISTER_SERVICE");
+        EVENT_NAMES.put(UNREGISTER_SERVICE_FAILED, "UNREGISTER_SERVICE_FAILED");
+        EVENT_NAMES.put(UNREGISTER_SERVICE_SUCCEEDED, "UNREGISTER_SERVICE_SUCCEEDED");
+        EVENT_NAMES.put(RESOLVE_SERVICE, "RESOLVE_SERVICE");
+        EVENT_NAMES.put(RESOLVE_SERVICE_FAILED, "RESOLVE_SERVICE_FAILED");
+        EVENT_NAMES.put(RESOLVE_SERVICE_SUCCEEDED, "RESOLVE_SERVICE_SUCCEEDED");
+        EVENT_NAMES.put(DAEMON_CLEANUP, "DAEMON_CLEANUP");
+        EVENT_NAMES.put(DAEMON_STARTUP, "DAEMON_STARTUP");
+        EVENT_NAMES.put(ENABLE, "ENABLE");
+        EVENT_NAMES.put(DISABLE, "DISABLE");
+        EVENT_NAMES.put(NATIVE_DAEMON_EVENT, "NATIVE_DAEMON_EVENT");
+    }
+
+    /** @hide */
+    public static String nameOf(int event) {
+        String name = EVENT_NAMES.get(event);
+        if (name == null) {
+            return Integer.toString(event);
+        }
+        return name;
+    }
+
+    private static final int FIRST_LISTENER_KEY = 1;
+
+    private final INsdServiceConnector mService;
+    private final Context mContext;
+
+    private int mListenerKey = FIRST_LISTENER_KEY;
+    @GuardedBy("mMapLock")
+    private final SparseArray mListenerMap = new SparseArray();
+    @GuardedBy("mMapLock")
+    private final SparseArray<NsdServiceInfo> mServiceMap = new SparseArray<>();
+    @GuardedBy("mMapLock")
+    private final SparseArray<Executor> mExecutorMap = new SparseArray<>();
+    private final Object mMapLock = new Object();
+    // Map of listener key sent by client -> per-network discovery tracker
+    @GuardedBy("mPerNetworkDiscoveryMap")
+    private final ArrayMap<Integer, PerNetworkDiscoveryTracker>
+            mPerNetworkDiscoveryMap = new ArrayMap<>();
+
+    private final ServiceHandler mHandler;
+
+    private class PerNetworkDiscoveryTracker {
+        final String mServiceType;
+        final int mProtocolType;
+        final DiscoveryListener mBaseListener;
+        final Executor mBaseExecutor;
+        final ArrayMap<Network, DelegatingDiscoveryListener> mPerNetworkListeners =
+                new ArrayMap<>();
+
+        final NetworkCallback mNetworkCb = new NetworkCallback() {
+            @Override
+            public void onAvailable(@NonNull Network network) {
+                final DelegatingDiscoveryListener wrappedListener = new DelegatingDiscoveryListener(
+                        network, mBaseListener);
+                mPerNetworkListeners.put(network, wrappedListener);
+                discoverServices(mServiceType, mProtocolType, network, mBaseExecutor,
+                        wrappedListener);
+            }
+
+            @Override
+            public void onLost(@NonNull Network network) {
+                final DelegatingDiscoveryListener listener = mPerNetworkListeners.get(network);
+                if (listener == null) return;
+                listener.notifyAllServicesLost();
+                // Listener will be removed from map in discovery stopped callback
+                stopServiceDiscovery(listener);
+            }
+        };
+
+        // Accessed from mHandler
+        private boolean mStopRequested;
+
+        public void start(@NonNull NetworkRequest request) {
+            final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+            cm.registerNetworkCallback(request, mNetworkCb, mHandler);
+            mHandler.post(() -> mBaseListener.onDiscoveryStarted(mServiceType));
+        }
+
+        /**
+         * Stop discovery on all networks tracked by this class.
+         *
+         * This will request all underlying listeners to stop, and the last one to stop will call
+         * onDiscoveryStopped or onStopDiscoveryFailed.
+         *
+         * Must be called on the handler thread.
+         */
+        public void requestStop() {
+            mHandler.post(() -> {
+                mStopRequested = true;
+                final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+                cm.unregisterNetworkCallback(mNetworkCb);
+                if (mPerNetworkListeners.size() == 0) {
+                    mBaseListener.onDiscoveryStopped(mServiceType);
+                    return;
+                }
+                for (int i = 0; i < mPerNetworkListeners.size(); i++) {
+                    final DelegatingDiscoveryListener listener = mPerNetworkListeners.valueAt(i);
+                    stopServiceDiscovery(listener);
+                }
+            });
+        }
+
+        private PerNetworkDiscoveryTracker(String serviceType, int protocolType,
+                Executor baseExecutor, DiscoveryListener baseListener) {
+            mServiceType = serviceType;
+            mProtocolType = protocolType;
+            mBaseExecutor = baseExecutor;
+            mBaseListener = baseListener;
+        }
+
+        /**
+         * Subset of NsdServiceInfo that is tracked to generate service lost notifications when a
+         * network is lost.
+         *
+         * Service lost notifications only contain service name, type and network, so only track
+         * that information (Network is known from the listener). This also implements
+         * equals/hashCode for usage in maps.
+         */
+        private class TrackedNsdInfo {
+            private final String mServiceName;
+            private final String mServiceType;
+            TrackedNsdInfo(NsdServiceInfo info) {
+                mServiceName = info.getServiceName();
+                mServiceType = info.getServiceType();
+            }
+
+            @Override
+            public int hashCode() {
+                return Objects.hash(mServiceName, mServiceType);
+            }
+
+            @Override
+            public boolean equals(Object obj) {
+                if (!(obj instanceof TrackedNsdInfo)) return false;
+                final TrackedNsdInfo other = (TrackedNsdInfo) obj;
+                return Objects.equals(mServiceName, other.mServiceName)
+                        && Objects.equals(mServiceType, other.mServiceType);
+            }
+        }
+
+        private class DelegatingDiscoveryListener implements DiscoveryListener {
+            private final Network mNetwork;
+            private final DiscoveryListener mWrapped;
+            private final ArraySet<TrackedNsdInfo> mFoundInfo = new ArraySet<>();
+
+            private DelegatingDiscoveryListener(Network network, DiscoveryListener listener) {
+                mNetwork = network;
+                mWrapped = listener;
+            }
+
+            void notifyAllServicesLost() {
+                for (int i = 0; i < mFoundInfo.size(); i++) {
+                    final TrackedNsdInfo trackedInfo = mFoundInfo.valueAt(i);
+                    final NsdServiceInfo serviceInfo = new NsdServiceInfo(
+                            trackedInfo.mServiceName, trackedInfo.mServiceType);
+                    serviceInfo.setNetwork(mNetwork);
+                    mWrapped.onServiceLost(serviceInfo);
+                }
+            }
+
+            @Override
+            public void onStartDiscoveryFailed(String serviceType, int errorCode) {
+                // The delegated listener is used when NsdManager takes care of starting/stopping
+                // discovery on multiple networks. Failure to start on one network is not a global
+                // failure to be reported up, as other networks may succeed: just log.
+                Log.e(TAG, "Failed to start discovery for " + serviceType + " on " + mNetwork
+                        + " with code " + errorCode);
+                mPerNetworkListeners.remove(mNetwork);
+            }
+
+            @Override
+            public void onDiscoveryStarted(String serviceType) {
+                // Wrapped listener was called upon registration, it is not called for discovery
+                // on each network
+            }
+
+            @Override
+            public void onStopDiscoveryFailed(String serviceType, int errorCode) {
+                Log.e(TAG, "Failed to stop discovery for " + serviceType + " on " + mNetwork
+                        + " with code " + errorCode);
+                mPerNetworkListeners.remove(mNetwork);
+                if (mStopRequested && mPerNetworkListeners.size() == 0) {
+                    // Do not report onStopDiscoveryFailed when some underlying listeners failed:
+                    // this does not mean that all listeners did, and onStopDiscoveryFailed is not
+                    // actionable anyway. Just report that discovery stopped.
+                    mWrapped.onDiscoveryStopped(serviceType);
+                }
+            }
+
+            @Override
+            public void onDiscoveryStopped(String serviceType) {
+                mPerNetworkListeners.remove(mNetwork);
+                if (mStopRequested && mPerNetworkListeners.size() == 0) {
+                    mWrapped.onDiscoveryStopped(serviceType);
+                }
+            }
+
+            @Override
+            public void onServiceFound(NsdServiceInfo serviceInfo) {
+                mFoundInfo.add(new TrackedNsdInfo(serviceInfo));
+                mWrapped.onServiceFound(serviceInfo);
+            }
+
+            @Override
+            public void onServiceLost(NsdServiceInfo serviceInfo) {
+                mFoundInfo.remove(new TrackedNsdInfo(serviceInfo));
+                mWrapped.onServiceLost(serviceInfo);
+            }
+        }
+    }
+
+    /**
+     * Create a new Nsd instance. Applications use
+     * {@link android.content.Context#getSystemService Context.getSystemService()} to retrieve
+     * {@link android.content.Context#NSD_SERVICE Context.NSD_SERVICE}.
+     * @param service the Binder interface
+     * @hide - hide this because it takes in a parameter of type INsdManager, which
+     * is a system private class.
+     */
+    public NsdManager(Context context, INsdManager service) {
+        mContext = context;
+
+        HandlerThread t = new HandlerThread("NsdManager");
+        t.start();
+        mHandler = new ServiceHandler(t.getLooper());
+
+        try {
+            mService = service.connect(new NsdCallbackImpl(mHandler));
+        } catch (RemoteException e) {
+            throw new RuntimeException("Failed to connect to NsdService");
+        }
+
+        // Only proactively start the daemon if the target SDK < S, otherwise the internal service
+        // would automatically start/stop the native daemon as needed.
+        if (!CompatChanges.isChangeEnabled(RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)) {
+            try {
+                mService.startDaemon();
+            } catch (RemoteException e) {
+                Log.e(TAG, "Failed to proactively start daemon");
+                // Continue: the daemon can still be started on-demand later
+            }
+        }
+    }
+
+    private static class NsdCallbackImpl extends INsdManagerCallback.Stub {
+        private final Handler mServHandler;
+
+        NsdCallbackImpl(Handler serviceHandler) {
+            mServHandler = serviceHandler;
+        }
+
+        private void sendInfo(int message, int listenerKey, NsdServiceInfo info) {
+            mServHandler.sendMessage(mServHandler.obtainMessage(message, 0, listenerKey, info));
+        }
+
+        private void sendError(int message, int listenerKey, int error) {
+            mServHandler.sendMessage(mServHandler.obtainMessage(message, error, listenerKey));
+        }
+
+        private void sendNoArg(int message, int listenerKey) {
+            mServHandler.sendMessage(mServHandler.obtainMessage(message, 0, listenerKey));
+        }
+
+        @Override
+        public void onDiscoverServicesStarted(int listenerKey, NsdServiceInfo info) {
+            sendInfo(DISCOVER_SERVICES_STARTED, listenerKey, info);
+        }
+
+        @Override
+        public void onDiscoverServicesFailed(int listenerKey, int error) {
+            sendError(DISCOVER_SERVICES_FAILED, listenerKey, error);
+        }
+
+        @Override
+        public void onServiceFound(int listenerKey, NsdServiceInfo info) {
+            sendInfo(SERVICE_FOUND, listenerKey, info);
+        }
+
+        @Override
+        public void onServiceLost(int listenerKey, NsdServiceInfo info) {
+            sendInfo(SERVICE_LOST, listenerKey, info);
+        }
+
+        @Override
+        public void onStopDiscoveryFailed(int listenerKey, int error) {
+            sendError(STOP_DISCOVERY_FAILED, listenerKey, error);
+        }
+
+        @Override
+        public void onStopDiscoverySucceeded(int listenerKey) {
+            sendNoArg(STOP_DISCOVERY_SUCCEEDED, listenerKey);
+        }
+
+        @Override
+        public void onRegisterServiceFailed(int listenerKey, int error) {
+            sendError(REGISTER_SERVICE_FAILED, listenerKey, error);
+        }
+
+        @Override
+        public void onRegisterServiceSucceeded(int listenerKey, NsdServiceInfo info) {
+            sendInfo(REGISTER_SERVICE_SUCCEEDED, listenerKey, info);
+        }
+
+        @Override
+        public void onUnregisterServiceFailed(int listenerKey, int error) {
+            sendError(UNREGISTER_SERVICE_FAILED, listenerKey, error);
+        }
+
+        @Override
+        public void onUnregisterServiceSucceeded(int listenerKey) {
+            sendNoArg(UNREGISTER_SERVICE_SUCCEEDED, listenerKey);
+        }
+
+        @Override
+        public void onResolveServiceFailed(int listenerKey, int error) {
+            sendError(RESOLVE_SERVICE_FAILED, listenerKey, error);
+        }
+
+        @Override
+        public void onResolveServiceSucceeded(int listenerKey, NsdServiceInfo info) {
+            sendInfo(RESOLVE_SERVICE_SUCCEEDED, listenerKey, info);
+        }
+    }
+
+    /**
+     * Failures are passed with {@link RegistrationListener#onRegistrationFailed},
+     * {@link RegistrationListener#onUnregistrationFailed},
+     * {@link DiscoveryListener#onStartDiscoveryFailed},
+     * {@link DiscoveryListener#onStopDiscoveryFailed} or {@link ResolveListener#onResolveFailed}.
+     *
+     * Indicates that the operation failed due to an internal error.
+     */
+    public static final int FAILURE_INTERNAL_ERROR               = 0;
+
+    /**
+     * Indicates that the operation failed because it is already active.
+     */
+    public static final int FAILURE_ALREADY_ACTIVE              = 3;
+
+    /**
+     * Indicates that the operation failed because the maximum outstanding
+     * requests from the applications have reached.
+     */
+    public static final int FAILURE_MAX_LIMIT                   = 4;
+
+    /** Interface for callback invocation for service discovery */
+    public interface DiscoveryListener {
+
+        public void onStartDiscoveryFailed(String serviceType, int errorCode);
+
+        public void onStopDiscoveryFailed(String serviceType, int errorCode);
+
+        public void onDiscoveryStarted(String serviceType);
+
+        public void onDiscoveryStopped(String serviceType);
+
+        public void onServiceFound(NsdServiceInfo serviceInfo);
+
+        public void onServiceLost(NsdServiceInfo serviceInfo);
+    }
+
+    /** Interface for callback invocation for service registration */
+    public interface RegistrationListener {
+
+        public void onRegistrationFailed(NsdServiceInfo serviceInfo, int errorCode);
+
+        public void onUnregistrationFailed(NsdServiceInfo serviceInfo, int errorCode);
+
+        public void onServiceRegistered(NsdServiceInfo serviceInfo);
+
+        public void onServiceUnregistered(NsdServiceInfo serviceInfo);
+    }
+
+    /** Interface for callback invocation for service resolution */
+    public interface ResolveListener {
+
+        public void onResolveFailed(NsdServiceInfo serviceInfo, int errorCode);
+
+        public void onServiceResolved(NsdServiceInfo serviceInfo);
+    }
+
+    @VisibleForTesting
+    class ServiceHandler extends Handler {
+        ServiceHandler(Looper looper) {
+            super(looper);
+        }
+
+        @Override
+        public void handleMessage(Message message) {
+            final int what = message.what;
+            final int key = message.arg2;
+            final Object listener;
+            final NsdServiceInfo ns;
+            final Executor executor;
+            synchronized (mMapLock) {
+                listener = mListenerMap.get(key);
+                ns = mServiceMap.get(key);
+                executor = mExecutorMap.get(key);
+            }
+            if (listener == null) {
+                Log.d(TAG, "Stale key " + message.arg2);
+                return;
+            }
+            if (DBG) {
+                Log.d(TAG, "received " + nameOf(what) + " for key " + key + ", service " + ns);
+            }
+            switch (what) {
+                case DISCOVER_SERVICES_STARTED:
+                    final String s = getNsdServiceInfoType((NsdServiceInfo) message.obj);
+                    executor.execute(() -> ((DiscoveryListener) listener).onDiscoveryStarted(s));
+                    break;
+                case DISCOVER_SERVICES_FAILED:
+                    removeListener(key);
+                    executor.execute(() -> ((DiscoveryListener) listener).onStartDiscoveryFailed(
+                            getNsdServiceInfoType(ns), message.arg1));
+                    break;
+                case SERVICE_FOUND:
+                    executor.execute(() -> ((DiscoveryListener) listener).onServiceFound(
+                            (NsdServiceInfo) message.obj));
+                    break;
+                case SERVICE_LOST:
+                    executor.execute(() -> ((DiscoveryListener) listener).onServiceLost(
+                            (NsdServiceInfo) message.obj));
+                    break;
+                case STOP_DISCOVERY_FAILED:
+                    // TODO: failure to stop discovery should be internal and retried internally, as
+                    // the effect for the client is indistinguishable from STOP_DISCOVERY_SUCCEEDED
+                    removeListener(key);
+                    executor.execute(() -> ((DiscoveryListener) listener).onStopDiscoveryFailed(
+                            getNsdServiceInfoType(ns), message.arg1));
+                    break;
+                case STOP_DISCOVERY_SUCCEEDED:
+                    removeListener(key);
+                    executor.execute(() -> ((DiscoveryListener) listener).onDiscoveryStopped(
+                            getNsdServiceInfoType(ns)));
+                    break;
+                case REGISTER_SERVICE_FAILED:
+                    removeListener(key);
+                    executor.execute(() -> ((RegistrationListener) listener).onRegistrationFailed(
+                            ns, message.arg1));
+                    break;
+                case REGISTER_SERVICE_SUCCEEDED:
+                    executor.execute(() -> ((RegistrationListener) listener).onServiceRegistered(
+                            (NsdServiceInfo) message.obj));
+                    break;
+                case UNREGISTER_SERVICE_FAILED:
+                    removeListener(key);
+                    executor.execute(() -> ((RegistrationListener) listener).onUnregistrationFailed(
+                            ns, message.arg1));
+                    break;
+                case UNREGISTER_SERVICE_SUCCEEDED:
+                    // TODO: do not unregister listener until service is unregistered, or provide
+                    // alternative way for unregistering ?
+                    removeListener(message.arg2);
+                    executor.execute(() -> ((RegistrationListener) listener).onServiceUnregistered(
+                            ns));
+                    break;
+                case RESOLVE_SERVICE_FAILED:
+                    removeListener(key);
+                    executor.execute(() -> ((ResolveListener) listener).onResolveFailed(
+                            ns, message.arg1));
+                    break;
+                case RESOLVE_SERVICE_SUCCEEDED:
+                    removeListener(key);
+                    executor.execute(() -> ((ResolveListener) listener).onServiceResolved(
+                            (NsdServiceInfo) message.obj));
+                    break;
+                default:
+                    Log.d(TAG, "Ignored " + message);
+                    break;
+            }
+        }
+    }
+
+    private int nextListenerKey() {
+        // Ensure mListenerKey >= FIRST_LISTENER_KEY;
+        mListenerKey = Math.max(FIRST_LISTENER_KEY, mListenerKey + 1);
+        return mListenerKey;
+    }
+
+    // Assert that the listener is not in the map, then add it and returns its key
+    private int putListener(Object listener, Executor e, NsdServiceInfo s) {
+        checkListener(listener);
+        final int key;
+        synchronized (mMapLock) {
+            int valueIndex = mListenerMap.indexOfValue(listener);
+            if (valueIndex != -1) {
+                throw new IllegalArgumentException("listener already in use");
+            }
+            key = nextListenerKey();
+            mListenerMap.put(key, listener);
+            mServiceMap.put(key, s);
+            mExecutorMap.put(key, e);
+        }
+        return key;
+    }
+
+    private void removeListener(int key) {
+        synchronized (mMapLock) {
+            mListenerMap.remove(key);
+            mServiceMap.remove(key);
+            mExecutorMap.remove(key);
+        }
+    }
+
+    private int getListenerKey(Object listener) {
+        checkListener(listener);
+        synchronized (mMapLock) {
+            int valueIndex = mListenerMap.indexOfValue(listener);
+            if (valueIndex == -1) {
+                throw new IllegalArgumentException("listener not registered");
+            }
+            return mListenerMap.keyAt(valueIndex);
+        }
+    }
+
+    private static String getNsdServiceInfoType(NsdServiceInfo s) {
+        if (s == null) return "?";
+        return s.getServiceType();
+    }
+
+    /**
+     * Register a service to be discovered by other services.
+     *
+     * <p> The function call immediately returns after sending a request to register service
+     * to the framework. The application is notified of a successful registration
+     * through the callback {@link RegistrationListener#onServiceRegistered} or a failure
+     * through {@link RegistrationListener#onRegistrationFailed}.
+     *
+     * <p> The application should call {@link #unregisterService} when the service
+     * registration is no longer required, and/or whenever the application is stopped.
+     *
+     * @param serviceInfo The service being registered
+     * @param protocolType The service discovery protocol
+     * @param listener The listener notifies of a successful registration and is used to
+     * unregister this service through a call on {@link #unregisterService}. Cannot be null.
+     * Cannot be in use for an active service registration.
+     */
+    public void registerService(NsdServiceInfo serviceInfo, int protocolType,
+            RegistrationListener listener) {
+        registerService(serviceInfo, protocolType, Runnable::run, listener);
+    }
+
+    /**
+     * Register a service to be discovered by other services.
+     *
+     * <p> The function call immediately returns after sending a request to register service
+     * to the framework. The application is notified of a successful registration
+     * through the callback {@link RegistrationListener#onServiceRegistered} or a failure
+     * through {@link RegistrationListener#onRegistrationFailed}.
+     *
+     * <p> The application should call {@link #unregisterService} when the service
+     * registration is no longer required, and/or whenever the application is stopped.
+     * @param serviceInfo The service being registered
+     * @param protocolType The service discovery protocol
+     * @param executor Executor to run listener callbacks with
+     * @param listener The listener notifies of a successful registration and is used to
+     * unregister this service through a call on {@link #unregisterService}. Cannot be null.
+     */
+    public void registerService(@NonNull NsdServiceInfo serviceInfo, int protocolType,
+            @NonNull Executor executor, @NonNull RegistrationListener listener) {
+        if (serviceInfo.getPort() <= 0) {
+            throw new IllegalArgumentException("Invalid port number");
+        }
+        checkServiceInfo(serviceInfo);
+        checkProtocol(protocolType);
+        int key = putListener(listener, executor, serviceInfo);
+        try {
+            mService.registerService(key, serviceInfo);
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Unregister a service registered through {@link #registerService}. A successful
+     * unregister is notified to the application with a call to
+     * {@link RegistrationListener#onServiceUnregistered}.
+     *
+     * @param listener This should be the listener object that was passed to
+     * {@link #registerService}. It identifies the service that should be unregistered
+     * and notifies of a successful or unsuccessful unregistration via the listener
+     * callbacks.  In API versions 20 and above, the listener object may be used for
+     * another service registration once the callback has been called.  In API versions <= 19,
+     * there is no entirely reliable way to know when a listener may be re-used, and a new
+     * listener should be created for each service registration request.
+     */
+    public void unregisterService(RegistrationListener listener) {
+        int id = getListenerKey(listener);
+        try {
+            mService.unregisterService(id);
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Initiate service discovery to browse for instances of a service type. Service discovery
+     * consumes network bandwidth and will continue until the application calls
+     * {@link #stopServiceDiscovery}.
+     *
+     * <p> The function call immediately returns after sending a request to start service
+     * discovery to the framework. The application is notified of a success to initiate
+     * discovery through the callback {@link DiscoveryListener#onDiscoveryStarted} or a failure
+     * through {@link DiscoveryListener#onStartDiscoveryFailed}.
+     *
+     * <p> Upon successful start, application is notified when a service is found with
+     * {@link DiscoveryListener#onServiceFound} or when a service is lost with
+     * {@link DiscoveryListener#onServiceLost}.
+     *
+     * <p> Upon failure to start, service discovery is not active and application does
+     * not need to invoke {@link #stopServiceDiscovery}
+     *
+     * <p> The application should call {@link #stopServiceDiscovery} when discovery of this
+     * service type is no longer required, and/or whenever the application is paused or
+     * stopped.
+     *
+     * @param serviceType The service type being discovered. Examples include "_http._tcp" for
+     * http services or "_ipp._tcp" for printers
+     * @param protocolType The service discovery protocol
+     * @param listener  The listener notifies of a successful discovery and is used
+     * to stop discovery on this serviceType through a call on {@link #stopServiceDiscovery}.
+     * Cannot be null. Cannot be in use for an active service discovery.
+     */
+    public void discoverServices(String serviceType, int protocolType, DiscoveryListener listener) {
+        discoverServices(serviceType, protocolType, (Network) null, Runnable::run, listener);
+    }
+
+    /**
+     * Initiate service discovery to browse for instances of a service type. Service discovery
+     * consumes network bandwidth and will continue until the application calls
+     * {@link #stopServiceDiscovery}.
+     *
+     * <p> The function call immediately returns after sending a request to start service
+     * discovery to the framework. The application is notified of a success to initiate
+     * discovery through the callback {@link DiscoveryListener#onDiscoveryStarted} or a failure
+     * through {@link DiscoveryListener#onStartDiscoveryFailed}.
+     *
+     * <p> Upon successful start, application is notified when a service is found with
+     * {@link DiscoveryListener#onServiceFound} or when a service is lost with
+     * {@link DiscoveryListener#onServiceLost}.
+     *
+     * <p> Upon failure to start, service discovery is not active and application does
+     * not need to invoke {@link #stopServiceDiscovery}
+     *
+     * <p> The application should call {@link #stopServiceDiscovery} when discovery of this
+     * service type is no longer required, and/or whenever the application is paused or
+     * stopped.
+     * @param serviceType The service type being discovered. Examples include "_http._tcp" for
+     * http services or "_ipp._tcp" for printers
+     * @param protocolType The service discovery protocol
+     * @param network Network to discover services on, or null to discover on all available networks
+     * @param executor Executor to run listener callbacks with
+     * @param listener  The listener notifies of a successful discovery and is used
+     * to stop discovery on this serviceType through a call on {@link #stopServiceDiscovery}.
+     */
+    public void discoverServices(@NonNull String serviceType, int protocolType,
+            @Nullable Network network, @NonNull Executor executor,
+            @NonNull DiscoveryListener listener) {
+        if (TextUtils.isEmpty(serviceType)) {
+            throw new IllegalArgumentException("Service type cannot be empty");
+        }
+        checkProtocol(protocolType);
+
+        NsdServiceInfo s = new NsdServiceInfo();
+        s.setServiceType(serviceType);
+        s.setNetwork(network);
+
+        int key = putListener(listener, executor, s);
+        try {
+            mService.discoverServices(key, s);
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Initiate service discovery to browse for instances of a service type. Service discovery
+     * consumes network bandwidth and will continue until the application calls
+     * {@link #stopServiceDiscovery}.
+     *
+     * <p> The function call immediately returns after sending a request to start service
+     * discovery to the framework. The application is notified of a success to initiate
+     * discovery through the callback {@link DiscoveryListener#onDiscoveryStarted} or a failure
+     * through {@link DiscoveryListener#onStartDiscoveryFailed}.
+     *
+     * <p> Upon successful start, application is notified when a service is found with
+     * {@link DiscoveryListener#onServiceFound} or when a service is lost with
+     * {@link DiscoveryListener#onServiceLost}.
+     *
+     * <p> Upon failure to start, service discovery is not active and application does
+     * not need to invoke {@link #stopServiceDiscovery}
+     *
+     * <p> The application should call {@link #stopServiceDiscovery} when discovery of this
+     * service type is no longer required, and/or whenever the application is paused or
+     * stopped.
+     *
+     * <p> During discovery, new networks may connect or existing networks may disconnect - for
+     * example if wifi is reconnected. When a service was found on a network that disconnects,
+     * {@link DiscoveryListener#onServiceLost} will be called. If a new network connects that
+     * matches the {@link NetworkRequest}, {@link DiscoveryListener#onServiceFound} will be called
+     * for services found on that network. Applications that do not want to track networks
+     * themselves are encouraged to use this method instead of other overloads of
+     * {@code discoverServices}, as they will receive proper notifications when a service becomes
+     * available or unavailable due to network changes.
+     * @param serviceType The service type being discovered. Examples include "_http._tcp" for
+     * http services or "_ipp._tcp" for printers
+     * @param protocolType The service discovery protocol
+     * @param networkRequest Request specifying networks that should be considered when discovering
+     * @param executor Executor to run listener callbacks with
+     * @param listener  The listener notifies of a successful discovery and is used
+     * to stop discovery on this serviceType through a call on {@link #stopServiceDiscovery}.
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    public void discoverServices(@NonNull String serviceType, int protocolType,
+            @NonNull NetworkRequest networkRequest, @NonNull Executor executor,
+            @NonNull DiscoveryListener listener) {
+        if (TextUtils.isEmpty(serviceType)) {
+            throw new IllegalArgumentException("Service type cannot be empty");
+        }
+        Objects.requireNonNull(networkRequest, "NetworkRequest cannot be null");
+        checkProtocol(protocolType);
+
+        NsdServiceInfo s = new NsdServiceInfo();
+        s.setServiceType(serviceType);
+
+        final int baseListenerKey = putListener(listener, executor, s);
+
+        final PerNetworkDiscoveryTracker discoveryInfo = new PerNetworkDiscoveryTracker(
+                serviceType, protocolType, executor, listener);
+
+        synchronized (mPerNetworkDiscoveryMap) {
+            mPerNetworkDiscoveryMap.put(baseListenerKey, discoveryInfo);
+            discoveryInfo.start(networkRequest);
+        }
+    }
+
+    /**
+     * Stop service discovery initiated with {@link #discoverServices}.  An active service
+     * discovery is notified to the application with {@link DiscoveryListener#onDiscoveryStarted}
+     * and it stays active until the application invokes a stop service discovery. A successful
+     * stop is notified to with a call to {@link DiscoveryListener#onDiscoveryStopped}.
+     *
+     * <p> Upon failure to stop service discovery, application is notified through
+     * {@link DiscoveryListener#onStopDiscoveryFailed}.
+     *
+     * @param listener This should be the listener object that was passed to {@link #discoverServices}.
+     * It identifies the discovery that should be stopped and notifies of a successful or
+     * unsuccessful stop.  In API versions 20 and above, the listener object may be used for
+     * another service discovery once the callback has been called.  In API versions <= 19,
+     * there is no entirely reliable way to know when a listener may be re-used, and a new
+     * listener should be created for each service discovery request.
+     */
+    public void stopServiceDiscovery(DiscoveryListener listener) {
+        int id = getListenerKey(listener);
+        // If this is a PerNetworkDiscovery request, handle it as such
+        synchronized (mPerNetworkDiscoveryMap) {
+            final PerNetworkDiscoveryTracker info = mPerNetworkDiscoveryMap.get(id);
+            if (info != null) {
+                info.requestStop();
+                return;
+            }
+        }
+        try {
+            mService.stopDiscovery(id);
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Resolve a discovered service. An application can resolve a service right before
+     * establishing a connection to fetch the IP and port details on which to setup
+     * the connection.
+     *
+     * @param serviceInfo service to be resolved
+     * @param listener to receive callback upon success or failure. Cannot be null.
+     * Cannot be in use for an active service resolution.
+     */
+    public void resolveService(NsdServiceInfo serviceInfo, ResolveListener listener) {
+        resolveService(serviceInfo, Runnable::run, listener);
+    }
+
+    /**
+     * Resolve a discovered service. An application can resolve a service right before
+     * establishing a connection to fetch the IP and port details on which to setup
+     * the connection.
+     * @param serviceInfo service to be resolved
+     * @param executor Executor to run listener callbacks with
+     * @param listener to receive callback upon success or failure.
+     */
+    public void resolveService(@NonNull NsdServiceInfo serviceInfo,
+            @NonNull Executor executor, @NonNull ResolveListener listener) {
+        checkServiceInfo(serviceInfo);
+        int key = putListener(listener, executor, serviceInfo);
+        try {
+            mService.resolveService(key, serviceInfo);
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+    }
+
+    private static void checkListener(Object listener) {
+        Objects.requireNonNull(listener, "listener cannot be null");
+    }
+
+    private static void checkProtocol(int protocolType) {
+        if (protocolType != PROTOCOL_DNS_SD) {
+            throw new IllegalArgumentException("Unsupported protocol");
+        }
+    }
+
+    private static void checkServiceInfo(NsdServiceInfo serviceInfo) {
+        Objects.requireNonNull(serviceInfo, "NsdServiceInfo cannot be null");
+        if (TextUtils.isEmpty(serviceInfo.getServiceName())) {
+            throw new IllegalArgumentException("Service name cannot be empty");
+        }
+        if (TextUtils.isEmpty(serviceInfo.getServiceType())) {
+            throw new IllegalArgumentException("Service type cannot be empty");
+        }
+    }
+}
diff --git a/framework-t/src/android/net/nsd/NsdServiceInfo.java b/framework-t/src/android/net/nsd/NsdServiceInfo.java
new file mode 100644
index 0000000..8506db1
--- /dev/null
+++ b/framework-t/src/android/net/nsd/NsdServiceInfo.java
@@ -0,0 +1,418 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.nsd;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.net.Network;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.text.TextUtils;
+import android.util.ArrayMap;
+import android.util.Base64;
+import android.util.Log;
+
+import java.io.UnsupportedEncodingException;
+import java.net.InetAddress;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.Map;
+
+/**
+ * A class representing service information for network service discovery
+ * {@see NsdManager}
+ */
+public final class NsdServiceInfo implements Parcelable {
+
+    private static final String TAG = "NsdServiceInfo";
+
+    private String mServiceName;
+
+    private String mServiceType;
+
+    private final ArrayMap<String, byte[]> mTxtRecord = new ArrayMap<>();
+
+    private InetAddress mHost;
+
+    private int mPort;
+
+    @Nullable
+    private Network mNetwork;
+
+    public NsdServiceInfo() {
+    }
+
+    /** @hide */
+    public NsdServiceInfo(String sn, String rt) {
+        mServiceName = sn;
+        mServiceType = rt;
+    }
+
+    /** Get the service name */
+    public String getServiceName() {
+        return mServiceName;
+    }
+
+    /** Set the service name */
+    public void setServiceName(String s) {
+        mServiceName = s;
+    }
+
+    /** Get the service type */
+    public String getServiceType() {
+        return mServiceType;
+    }
+
+    /** Set the service type */
+    public void setServiceType(String s) {
+        mServiceType = s;
+    }
+
+    /** Get the host address. The host address is valid for a resolved service. */
+    public InetAddress getHost() {
+        return mHost;
+    }
+
+    /** Set the host address */
+    public void setHost(InetAddress s) {
+        mHost = s;
+    }
+
+    /** Get port number. The port number is valid for a resolved service. */
+    public int getPort() {
+        return mPort;
+    }
+
+    /** Set port number */
+    public void setPort(int p) {
+        mPort = p;
+    }
+
+    /**
+     * Unpack txt information from a base-64 encoded byte array.
+     *
+     * @param rawRecords The raw base64 encoded records string read from netd.
+     *
+     * @hide
+     */
+    public void setTxtRecords(@NonNull String rawRecords) {
+        byte[] txtRecordsRawBytes = Base64.decode(rawRecords, Base64.DEFAULT);
+
+        // There can be multiple TXT records after each other. Each record has to following format:
+        //
+        // byte                  type                  required   meaning
+        // -------------------   -------------------   --------   ----------------------------------
+        // 0                     unsigned 8 bit        yes        size of record excluding this byte
+        // 1 - n                 ASCII but not '='     yes        key
+        // n + 1                 '='                   optional   separator of key and value
+        // n + 2 - record size   uninterpreted bytes   optional   value
+        //
+        // Example legal records:
+        // [11, 'm', 'y', 'k', 'e', 'y', '=', 0x0, 0x4, 0x65, 0x7, 0xff]
+        // [17, 'm', 'y', 'K', 'e', 'y', 'W', 'i', 't', 'h', 'N', 'o', 'V', 'a', 'l', 'u', 'e', '=']
+        // [12, 'm', 'y', 'B', 'o', 'o', 'l', 'e', 'a', 'n', 'K', 'e', 'y']
+        //
+        // Example corrupted records
+        // [3, =, 1, 2]    <- key is empty
+        // [3, 0, =, 2]    <- key contains non-ASCII character. We handle this by replacing the
+        //                    invalid characters instead of skipping the record.
+        // [30, 'a', =, 2] <- length exceeds total left over bytes in the TXT records array, we
+        //                    handle this by reducing the length of the record as needed.
+        int pos = 0;
+        while (pos < txtRecordsRawBytes.length) {
+            // recordLen is an unsigned 8 bit value
+            int recordLen = txtRecordsRawBytes[pos] & 0xff;
+            pos += 1;
+
+            try {
+                if (recordLen == 0) {
+                    throw new IllegalArgumentException("Zero sized txt record");
+                } else if (pos + recordLen > txtRecordsRawBytes.length) {
+                    Log.w(TAG, "Corrupt record length (pos = " + pos + "): " + recordLen);
+                    recordLen = txtRecordsRawBytes.length - pos;
+                }
+
+                // Decode key-value records
+                String key = null;
+                byte[] value = null;
+                int valueLen = 0;
+                for (int i = pos; i < pos + recordLen; i++) {
+                    if (key == null) {
+                        if (txtRecordsRawBytes[i] == '=') {
+                            key = new String(txtRecordsRawBytes, pos, i - pos,
+                                    StandardCharsets.US_ASCII);
+                        }
+                    } else {
+                        if (value == null) {
+                            value = new byte[recordLen - key.length() - 1];
+                        }
+                        value[valueLen] = txtRecordsRawBytes[i];
+                        valueLen++;
+                    }
+                }
+
+                // If '=' was not found we have a boolean record
+                if (key == null) {
+                    key = new String(txtRecordsRawBytes, pos, recordLen, StandardCharsets.US_ASCII);
+                }
+
+                if (TextUtils.isEmpty(key)) {
+                    // Empty keys are not allowed (RFC6763 6.4)
+                    throw new IllegalArgumentException("Invalid txt record (key is empty)");
+                }
+
+                if (getAttributes().containsKey(key)) {
+                    // When we have a duplicate record, the later ones are ignored (RFC6763 6.4)
+                    throw new IllegalArgumentException("Invalid txt record (duplicate key \"" + key + "\")");
+                }
+
+                setAttribute(key, value);
+            } catch (IllegalArgumentException e) {
+                Log.e(TAG, "While parsing txt records (pos = " + pos + "): " + e.getMessage());
+            }
+
+            pos += recordLen;
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public void setAttribute(String key, byte[] value) {
+        if (TextUtils.isEmpty(key)) {
+            throw new IllegalArgumentException("Key cannot be empty");
+        }
+
+        // Key must be printable US-ASCII, excluding =.
+        for (int i = 0; i < key.length(); ++i) {
+            char character = key.charAt(i);
+            if (character < 0x20 || character > 0x7E) {
+                throw new IllegalArgumentException("Key strings must be printable US-ASCII");
+            } else if (character == 0x3D) {
+                throw new IllegalArgumentException("Key strings must not include '='");
+            }
+        }
+
+        // Key length + value length must be < 255.
+        if (key.length() + (value == null ? 0 : value.length) >= 255) {
+            throw new IllegalArgumentException("Key length + value length must be < 255 bytes");
+        }
+
+        // Warn if key is > 9 characters, as recommended by RFC 6763 section 6.4.
+        if (key.length() > 9) {
+            Log.w(TAG, "Key lengths > 9 are discouraged: " + key);
+        }
+
+        // Check against total TXT record size limits.
+        // Arbitrary 400 / 1300 byte limits taken from RFC 6763 section 6.2.
+        int txtRecordSize = getTxtRecordSize();
+        int futureSize = txtRecordSize + key.length() + (value == null ? 0 : value.length) + 2;
+        if (futureSize > 1300) {
+            throw new IllegalArgumentException("Total length of attributes must be < 1300 bytes");
+        } else if (futureSize > 400) {
+            Log.w(TAG, "Total length of all attributes exceeds 400 bytes; truncation may occur");
+        }
+
+        mTxtRecord.put(key, value);
+    }
+
+    /**
+     * Add a service attribute as a key/value pair.
+     *
+     * <p> Service attributes are included as DNS-SD TXT record pairs.
+     *
+     * <p> The key must be US-ASCII printable characters, excluding the '=' character.  Values may
+     * be UTF-8 strings or null.  The total length of key + value must be less than 255 bytes.
+     *
+     * <p> Keys should be short, ideally no more than 9 characters, and unique per instance of
+     * {@link NsdServiceInfo}.  Calling {@link #setAttribute} twice with the same key will overwrite
+     * first value.
+     */
+    public void setAttribute(String key, String value) {
+        try {
+            setAttribute(key, value == null ? (byte []) null : value.getBytes("UTF-8"));
+        } catch (UnsupportedEncodingException e) {
+            throw new IllegalArgumentException("Value must be UTF-8");
+        }
+    }
+
+    /** Remove an attribute by key */
+    public void removeAttribute(String key) {
+        mTxtRecord.remove(key);
+    }
+
+    /**
+     * Retrieve attributes as a map of String keys to byte[] values. The attributes map is only
+     * valid for a resolved service.
+     *
+     * <p> The returned map is unmodifiable; changes must be made through {@link #setAttribute} and
+     * {@link #removeAttribute}.
+     */
+    public Map<String, byte[]> getAttributes() {
+        return Collections.unmodifiableMap(mTxtRecord);
+    }
+
+    private int getTxtRecordSize() {
+        int txtRecordSize = 0;
+        for (Map.Entry<String, byte[]> entry : mTxtRecord.entrySet()) {
+            txtRecordSize += 2;  // One for the length byte, one for the = between key and value.
+            txtRecordSize += entry.getKey().length();
+            byte[] value = entry.getValue();
+            txtRecordSize += value == null ? 0 : value.length;
+        }
+        return txtRecordSize;
+    }
+
+    /** @hide */
+    public @NonNull byte[] getTxtRecord() {
+        int txtRecordSize = getTxtRecordSize();
+        if (txtRecordSize == 0) {
+            return new byte[]{};
+        }
+
+        byte[] txtRecord = new byte[txtRecordSize];
+        int ptr = 0;
+        for (Map.Entry<String, byte[]> entry : mTxtRecord.entrySet()) {
+            String key = entry.getKey();
+            byte[] value = entry.getValue();
+
+            // One byte to record the length of this key/value pair.
+            txtRecord[ptr++] = (byte) (key.length() + (value == null ? 0 : value.length) + 1);
+
+            // The key, in US-ASCII.
+            // Note: use the StandardCharsets const here because it doesn't raise exceptions and we
+            // already know the key is ASCII at this point.
+            System.arraycopy(key.getBytes(StandardCharsets.US_ASCII), 0, txtRecord, ptr,
+                    key.length());
+            ptr += key.length();
+
+            // US-ASCII '=' character.
+            txtRecord[ptr++] = (byte)'=';
+
+            // The value, as any raw bytes.
+            if (value != null) {
+                System.arraycopy(value, 0, txtRecord, ptr, value.length);
+                ptr += value.length;
+            }
+        }
+        return txtRecord;
+    }
+
+    /**
+     * Get the network where the service can be found.
+     *
+     * This is never null if this {@link NsdServiceInfo} was obtained from
+     * {@link NsdManager#discoverServices} or {@link NsdManager#resolveService}.
+     */
+    @Nullable
+    public Network getNetwork() {
+        return mNetwork;
+    }
+
+    /**
+     * Set the network where the service can be found.
+     * @param network The network, or null to search for, or to announce, the service on all
+     *                connected networks.
+     */
+    public void setNetwork(@Nullable Network network) {
+        mNetwork = network;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("name: ").append(mServiceName)
+                .append(", type: ").append(mServiceType)
+                .append(", host: ").append(mHost)
+                .append(", port: ").append(mPort)
+                .append(", network: ").append(mNetwork);
+
+        byte[] txtRecord = getTxtRecord();
+        sb.append(", txtRecord: ").append(new String(txtRecord, StandardCharsets.UTF_8));
+        return sb.toString();
+    }
+
+    /** Implement the Parcelable interface */
+    public int describeContents() {
+        return 0;
+    }
+
+    /** Implement the Parcelable interface */
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeString(mServiceName);
+        dest.writeString(mServiceType);
+        if (mHost != null) {
+            dest.writeInt(1);
+            dest.writeByteArray(mHost.getAddress());
+        } else {
+            dest.writeInt(0);
+        }
+        dest.writeInt(mPort);
+
+        // TXT record key/value pairs.
+        dest.writeInt(mTxtRecord.size());
+        for (String key : mTxtRecord.keySet()) {
+            byte[] value = mTxtRecord.get(key);
+            if (value != null) {
+                dest.writeInt(1);
+                dest.writeInt(value.length);
+                dest.writeByteArray(value);
+            } else {
+                dest.writeInt(0);
+            }
+            dest.writeString(key);
+        }
+
+        dest.writeParcelable(mNetwork, 0);
+    }
+
+    /** Implement the Parcelable interface */
+    public static final @android.annotation.NonNull Creator<NsdServiceInfo> CREATOR =
+        new Creator<NsdServiceInfo>() {
+            public NsdServiceInfo createFromParcel(Parcel in) {
+                NsdServiceInfo info = new NsdServiceInfo();
+                info.mServiceName = in.readString();
+                info.mServiceType = in.readString();
+
+                if (in.readInt() == 1) {
+                    try {
+                        info.mHost = InetAddress.getByAddress(in.createByteArray());
+                    } catch (java.net.UnknownHostException e) {}
+                }
+
+                info.mPort = in.readInt();
+
+                // TXT record key/value pairs.
+                int recordCount = in.readInt();
+                for (int i = 0; i < recordCount; ++i) {
+                    byte[] valueArray = null;
+                    if (in.readInt() == 1) {
+                        int valueLength = in.readInt();
+                        valueArray = new byte[valueLength];
+                        in.readByteArray(valueArray);
+                    }
+                    info.mTxtRecord.put(in.readString(), valueArray);
+                }
+                info.mNetwork = in.readParcelable(null, Network.class);
+                return info;
+            }
+
+            public NsdServiceInfo[] newArray(int size) {
+                return new NsdServiceInfo[size];
+            }
+        };
+}
diff --git a/service-t/Android.bp b/service-t/Android.bp
index 8851554..52bc2c0 100644
--- a/service-t/Android.bp
+++ b/service-t/Android.bp
@@ -19,6 +19,25 @@
     default_applicable_licenses: ["Android-Apache-2.0"],
 }
 
+// Include build rules from Sources.bp
+// sc-mainline-prod only: do not include Sources.bp
+// build = ["Sources.bp"]
+
+filegroup {
+    name: "service-connectivity-tiramisu-sources",
+    srcs: [
+        // sc-mainline-prod only: Building T sources is disabled on this branch.
+        // "src/**/*.java",
+        "src/com/android/server/ConnectivityServiceInitializer.java",
+        // filegroup contains empty stubs on sc-mainline-prod.
+        ":services.connectivity-tiramisu-updatable-sources",
+    ],
+    visibility: ["//visibility:private"],
+}
+// The above filegroup can be used to specify different sources depending
+// on the branch, while minimizing merge conflicts in the rest of the
+// build rules.
+
 // This builds T+ services depending on framework-connectivity-t
 // hidden symbols separately from the S+ services, to ensure that S+
 // services cannot accidentally depend on T+ hidden symbols from
@@ -29,9 +48,7 @@
     // TODO(b/210962470): Bump this to at least S, and then T.
     min_sdk_version: "30",
     srcs: [
-        "src/**/*.java",
-        ":ethernet-service-updatable-sources",
-        ":services.connectivity-tiramisu-updatable-sources",
+        ":service-connectivity-tiramisu-sources",
     ],
     libs: [
         "framework-annotations-lib",
diff --git a/service-t/Sources.bp b/service-t/Sources.bp
new file mode 100644
index 0000000..4e669b6
--- /dev/null
+++ b/service-t/Sources.bp
@@ -0,0 +1,95 @@
+//
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// NetworkStats related libraries.
+
+filegroup {
+    name: "services.connectivity-netstats-sources",
+    srcs: [
+        "src/com/android/server/net/NetworkIdentity*.java",
+        "src/com/android/server/net/NetworkStats*.java",
+        "src/com/android/server/net/BpfInterfaceMapUpdater.java",
+        "src/com/android/server/net/InterfaceMapValue.java",
+        "src/com/android/server/net/CookieTagMapKey.java",
+        "src/com/android/server/net/CookieTagMapValue.java",
+        "src/com/android/server/net/StatsMapKey.java",
+        "src/com/android/server/net/StatsMapValue.java",
+        "src/com/android/server/net/UidStatsMapKey.java",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// For test code only.
+filegroup {
+    name: "lib_networkStatsFactory_native",
+    srcs: [
+        "jni/com_android_server_net_NetworkStatsFactory.cpp",
+    ],
+    path: "jni",
+    visibility: [
+        "//packages/modules/Connectivity:__subpackages__",
+    ],
+}
+
+filegroup {
+    name: "services.connectivity-netstats-jni-sources",
+    srcs: [
+        "jni/com_android_server_net_NetworkStatsFactory.cpp",
+        "jni/com_android_server_net_NetworkStatsService.cpp",
+    ],
+    path: "jni",
+    visibility: [
+        "//packages/modules/Connectivity:__subpackages__",
+    ],
+}
+
+// Connectivity-T common libraries.
+
+// TODO: remove this empty filegroup.
+filegroup {
+    name: "services.connectivity-tiramisu-sources",
+    srcs: [],
+    path: "src",
+    visibility: ["//frameworks/base/services/core"],
+}
+
+cc_library_shared {
+    name: "libcom_android_net_module_util_jni",
+    min_sdk_version: "30",
+    cflags: [
+        "-Wall",
+        "-Werror",
+        "-Wno-unused-parameter",
+        "-Wthread-safety",
+    ],
+    srcs: [
+        "jni/onload.cpp",
+    ],
+    stl: "libc++_static",
+    static_libs: [
+        "libnet_utils_device_common_bpfjni",
+    ],
+    shared_libs: [
+        "liblog",
+        "libnativehelper",
+    ],
+    apex_available: [
+        "//apex_available:platform",
+    ],
+}
diff --git a/service-t/jni/com_android_server_net_NetworkStatsFactory.cpp b/service-t/jni/com_android_server_net_NetworkStatsFactory.cpp
new file mode 100644
index 0000000..8b6526f
--- /dev/null
+++ b/service-t/jni/com_android_server_net_NetworkStatsFactory.cpp
@@ -0,0 +1,362 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "NetworkStats"
+
+#include <errno.h>
+#include <inttypes.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <vector>
+
+#include <jni.h>
+
+#include <nativehelper/JNIHelp.h>
+#include <nativehelper/ScopedUtfChars.h>
+#include <nativehelper/ScopedLocalRef.h>
+#include <nativehelper/ScopedPrimitiveArray.h>
+
+#include <utils/Log.h>
+#include <utils/misc.h>
+
+#include "android-base/unique_fd.h"
+#include "bpf/BpfUtils.h"
+#include "netdbpf/BpfNetworkStats.h"
+
+using android::bpf::parseBpfNetworkStatsDetail;
+using android::bpf::stats_line;
+
+namespace android {
+
+static jclass gStringClass;
+
+static struct {
+    jfieldID size;
+    jfieldID capacity;
+    jfieldID iface;
+    jfieldID uid;
+    jfieldID set;
+    jfieldID tag;
+    jfieldID metered;
+    jfieldID roaming;
+    jfieldID defaultNetwork;
+    jfieldID rxBytes;
+    jfieldID rxPackets;
+    jfieldID txBytes;
+    jfieldID txPackets;
+    jfieldID operations;
+} gNetworkStatsClassInfo;
+
+static jobjectArray get_string_array(JNIEnv* env, jobject obj, jfieldID field, int size, bool grow)
+{
+    if (!grow) {
+        jobjectArray array = (jobjectArray)env->GetObjectField(obj, field);
+        if (array != NULL) {
+            return array;
+        }
+    }
+    return env->NewObjectArray(size, gStringClass, NULL);
+}
+
+static jintArray get_int_array(JNIEnv* env, jobject obj, jfieldID field, int size, bool grow)
+{
+    if (!grow) {
+        jintArray array = (jintArray)env->GetObjectField(obj, field);
+        if (array != NULL) {
+            return array;
+        }
+    }
+    return env->NewIntArray(size);
+}
+
+static jlongArray get_long_array(JNIEnv* env, jobject obj, jfieldID field, int size, bool grow)
+{
+    if (!grow) {
+        jlongArray array = (jlongArray)env->GetObjectField(obj, field);
+        if (array != NULL) {
+            return array;
+        }
+    }
+    return env->NewLongArray(size);
+}
+
+static int legacyReadNetworkStatsDetail(std::vector<stats_line>* lines,
+                                        const std::vector<std::string>& limitIfaces,
+                                        int limitTag, int limitUid, const char* path) {
+    FILE* fp = fopen(path, "re");
+    if (fp == NULL) {
+        return -1;
+    }
+
+    int lastIdx = 1;
+    int idx;
+    char buffer[384];
+    while (fgets(buffer, sizeof(buffer), fp) != NULL) {
+        stats_line s;
+        int64_t rawTag;
+        char* pos = buffer;
+        char* endPos;
+        // First field is the index.
+        idx = (int)strtol(pos, &endPos, 10);
+        //ALOGI("Index #%d: %s", idx, buffer);
+        if (pos == endPos) {
+            // Skip lines that don't start with in index.  In particular,
+            // this will skip the initial header line.
+            continue;
+        }
+        if (idx != lastIdx + 1) {
+            ALOGE("inconsistent idx=%d after lastIdx=%d: %s", idx, lastIdx, buffer);
+            fclose(fp);
+            return -1;
+        }
+        lastIdx = idx;
+        pos = endPos;
+        // Skip whitespace.
+        while (*pos == ' ') {
+            pos++;
+        }
+        // Next field is iface.
+        int ifaceIdx = 0;
+        while (*pos != ' ' && *pos != 0 && ifaceIdx < (int)(sizeof(s.iface)-1)) {
+            s.iface[ifaceIdx] = *pos;
+            ifaceIdx++;
+            pos++;
+        }
+        if (*pos != ' ') {
+            ALOGE("bad iface: %s", buffer);
+            fclose(fp);
+            return -1;
+        }
+        s.iface[ifaceIdx] = 0;
+        if (limitIfaces.size() > 0) {
+            // Is this an iface the caller is interested in?
+            int i = 0;
+            while (i < (int)limitIfaces.size()) {
+                if (limitIfaces[i] == s.iface) {
+                    break;
+                }
+                i++;
+            }
+            if (i >= (int)limitIfaces.size()) {
+                // Nothing matched; skip this line.
+                //ALOGI("skipping due to iface: %s", buffer);
+                continue;
+            }
+        }
+
+        // Ignore whitespace
+        while (*pos == ' ') pos++;
+
+        // Find end of tag field
+        endPos = pos;
+        while (*endPos != ' ') endPos++;
+
+        // Three digit field is always 0x0, otherwise parse
+        if (endPos - pos == 3) {
+            rawTag = 0;
+        } else {
+            if (sscanf(pos, "%" PRIx64, &rawTag) != 1) {
+                ALOGE("bad tag: %s", pos);
+                fclose(fp);
+                return -1;
+            }
+        }
+        s.tag = rawTag >> 32;
+        if (limitTag != -1 && s.tag != static_cast<uint32_t>(limitTag)) {
+            //ALOGI("skipping due to tag: %s", buffer);
+            continue;
+        }
+        pos = endPos;
+
+        // Ignore whitespace
+        while (*pos == ' ') pos++;
+
+        // Parse remaining fields.
+        if (sscanf(pos, "%u %u %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64,
+                &s.uid, &s.set, &s.rxBytes, &s.rxPackets,
+                &s.txBytes, &s.txPackets) == 6) {
+            if (limitUid != -1 && static_cast<uint32_t>(limitUid) != s.uid) {
+                //ALOGI("skipping due to uid: %s", buffer);
+                continue;
+            }
+            lines->push_back(s);
+        } else {
+            //ALOGI("skipping due to bad remaining fields: %s", pos);
+        }
+    }
+
+    if (fclose(fp) != 0) {
+        ALOGE("Failed to close netstats file");
+        return -1;
+    }
+    return 0;
+}
+
+static int statsLinesToNetworkStats(JNIEnv* env, jclass clazz, jobject stats,
+                            std::vector<stats_line>& lines) {
+    int size = lines.size();
+
+    bool grow = size > env->GetIntField(stats, gNetworkStatsClassInfo.capacity);
+
+    ScopedLocalRef<jobjectArray> iface(env, get_string_array(env, stats,
+            gNetworkStatsClassInfo.iface, size, grow));
+    if (iface.get() == NULL) return -1;
+    ScopedIntArrayRW uid(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.uid, size, grow));
+    if (uid.get() == NULL) return -1;
+    ScopedIntArrayRW set(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.set, size, grow));
+    if (set.get() == NULL) return -1;
+    ScopedIntArrayRW tag(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.tag, size, grow));
+    if (tag.get() == NULL) return -1;
+    ScopedIntArrayRW metered(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.metered, size, grow));
+    if (metered.get() == NULL) return -1;
+    ScopedIntArrayRW roaming(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.roaming, size, grow));
+    if (roaming.get() == NULL) return -1;
+    ScopedIntArrayRW defaultNetwork(env, get_int_array(env, stats,
+            gNetworkStatsClassInfo.defaultNetwork, size, grow));
+    if (defaultNetwork.get() == NULL) return -1;
+    ScopedLongArrayRW rxBytes(env, get_long_array(env, stats,
+            gNetworkStatsClassInfo.rxBytes, size, grow));
+    if (rxBytes.get() == NULL) return -1;
+    ScopedLongArrayRW rxPackets(env, get_long_array(env, stats,
+            gNetworkStatsClassInfo.rxPackets, size, grow));
+    if (rxPackets.get() == NULL) return -1;
+    ScopedLongArrayRW txBytes(env, get_long_array(env, stats,
+            gNetworkStatsClassInfo.txBytes, size, grow));
+    if (txBytes.get() == NULL) return -1;
+    ScopedLongArrayRW txPackets(env, get_long_array(env, stats,
+            gNetworkStatsClassInfo.txPackets, size, grow));
+    if (txPackets.get() == NULL) return -1;
+    ScopedLongArrayRW operations(env, get_long_array(env, stats,
+            gNetworkStatsClassInfo.operations, size, grow));
+    if (operations.get() == NULL) return -1;
+
+    for (int i = 0; i < size; i++) {
+        ScopedLocalRef<jstring> ifaceString(env, env->NewStringUTF(lines[i].iface));
+        env->SetObjectArrayElement(iface.get(), i, ifaceString.get());
+
+        uid[i] = lines[i].uid;
+        set[i] = lines[i].set;
+        tag[i] = lines[i].tag;
+        // Metered, roaming and defaultNetwork are populated in Java-land.
+        rxBytes[i] = lines[i].rxBytes;
+        rxPackets[i] = lines[i].rxPackets;
+        txBytes[i] = lines[i].txBytes;
+        txPackets[i] = lines[i].txPackets;
+    }
+
+    env->SetIntField(stats, gNetworkStatsClassInfo.size, size);
+    if (grow) {
+        env->SetIntField(stats, gNetworkStatsClassInfo.capacity, size);
+        env->SetObjectField(stats, gNetworkStatsClassInfo.iface, iface.get());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.uid, uid.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.set, set.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.tag, tag.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.metered, metered.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.roaming, roaming.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.defaultNetwork,
+                defaultNetwork.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.rxBytes, rxBytes.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.rxPackets, rxPackets.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.txBytes, txBytes.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.txPackets, txPackets.getJavaArray());
+        env->SetObjectField(stats, gNetworkStatsClassInfo.operations, operations.getJavaArray());
+    }
+    return 0;
+}
+
+static int readNetworkStatsDetail(JNIEnv* env, jclass clazz, jobject stats, jstring path,
+                                  jint limitUid, jobjectArray limitIfacesObj, jint limitTag,
+                                  jboolean useBpfStats) {
+
+    std::vector<std::string> limitIfaces;
+    if (limitIfacesObj != NULL && env->GetArrayLength(limitIfacesObj) > 0) {
+        int num = env->GetArrayLength(limitIfacesObj);
+        for (int i = 0; i < num; i++) {
+            jstring string = (jstring)env->GetObjectArrayElement(limitIfacesObj, i);
+            ScopedUtfChars string8(env, string);
+            if (string8.c_str() != NULL) {
+                limitIfaces.push_back(std::string(string8.c_str()));
+            }
+        }
+    }
+    std::vector<stats_line> lines;
+
+
+    if (useBpfStats) {
+        if (parseBpfNetworkStatsDetail(&lines, limitIfaces, limitTag, limitUid) < 0)
+            return -1;
+    } else {
+        ScopedUtfChars path8(env, path);
+        if (path8.c_str() == NULL) {
+            ALOGE("the qtaguid legacy path is invalid: %s", path8.c_str());
+            return -1;
+        }
+        if (legacyReadNetworkStatsDetail(&lines, limitIfaces, limitTag,
+                                         limitUid, path8.c_str()) < 0)
+            return -1;
+    }
+
+    return statsLinesToNetworkStats(env, clazz, stats, lines);
+}
+
+static int readNetworkStatsDev(JNIEnv* env, jclass clazz, jobject stats) {
+    std::vector<stats_line> lines;
+
+    if (parseBpfNetworkStatsDev(&lines) < 0)
+            return -1;
+
+    return statsLinesToNetworkStats(env, clazz, stats, lines);
+}
+
+static const JNINativeMethod gMethods[] = {
+        { "nativeReadNetworkStatsDetail",
+                "(Landroid/net/NetworkStats;Ljava/lang/String;I[Ljava/lang/String;IZ)I",
+                (void*) readNetworkStatsDetail },
+        { "nativeReadNetworkStatsDev", "(Landroid/net/NetworkStats;)I",
+                (void*) readNetworkStatsDev },
+};
+
+int register_android_server_net_NetworkStatsFactory(JNIEnv* env) {
+    int err = jniRegisterNativeMethods(env, "com/android/server/net/NetworkStatsFactory", gMethods,
+            NELEM(gMethods));
+    gStringClass = env->FindClass("java/lang/String");
+    gStringClass = static_cast<jclass>(env->NewGlobalRef(gStringClass));
+
+    jclass clazz = env->FindClass("android/net/NetworkStats");
+    gNetworkStatsClassInfo.size = env->GetFieldID(clazz, "size", "I");
+    gNetworkStatsClassInfo.capacity = env->GetFieldID(clazz, "capacity", "I");
+    gNetworkStatsClassInfo.iface = env->GetFieldID(clazz, "iface", "[Ljava/lang/String;");
+    gNetworkStatsClassInfo.uid = env->GetFieldID(clazz, "uid", "[I");
+    gNetworkStatsClassInfo.set = env->GetFieldID(clazz, "set", "[I");
+    gNetworkStatsClassInfo.tag = env->GetFieldID(clazz, "tag", "[I");
+    gNetworkStatsClassInfo.metered = env->GetFieldID(clazz, "metered", "[I");
+    gNetworkStatsClassInfo.roaming = env->GetFieldID(clazz, "roaming", "[I");
+    gNetworkStatsClassInfo.defaultNetwork = env->GetFieldID(clazz, "defaultNetwork", "[I");
+    gNetworkStatsClassInfo.rxBytes = env->GetFieldID(clazz, "rxBytes", "[J");
+    gNetworkStatsClassInfo.rxPackets = env->GetFieldID(clazz, "rxPackets", "[J");
+    gNetworkStatsClassInfo.txBytes = env->GetFieldID(clazz, "txBytes", "[J");
+    gNetworkStatsClassInfo.txPackets = env->GetFieldID(clazz, "txPackets", "[J");
+    gNetworkStatsClassInfo.operations = env->GetFieldID(clazz, "operations", "[J");
+
+    return err;
+}
+
+}
diff --git a/service-t/jni/com_android_server_net_NetworkStatsService.cpp b/service-t/jni/com_android_server_net_NetworkStatsService.cpp
new file mode 100644
index 0000000..39cbaf7
--- /dev/null
+++ b/service-t/jni/com_android_server_net_NetworkStatsService.cpp
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "NetworkStatsNative"
+
+#include <cutils/qtaguid.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <jni.h>
+#include <nativehelper/ScopedUtfChars.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <utils/Log.h>
+#include <utils/misc.h>
+
+#include "bpf/BpfUtils.h"
+#include "netdbpf/BpfNetworkStats.h"
+
+using android::bpf::bpfGetUidStats;
+using android::bpf::bpfGetIfaceStats;
+
+namespace android {
+
+// NOTE: keep these in sync with TrafficStats.java
+static const uint64_t UNKNOWN = -1;
+
+enum StatsType {
+    RX_BYTES = 0,
+    RX_PACKETS = 1,
+    TX_BYTES = 2,
+    TX_PACKETS = 3,
+    TCP_RX_PACKETS = 4,
+    TCP_TX_PACKETS = 5
+};
+
+static uint64_t getStatsType(Stats* stats, StatsType type) {
+    switch (type) {
+        case RX_BYTES:
+            return stats->rxBytes;
+        case RX_PACKETS:
+            return stats->rxPackets;
+        case TX_BYTES:
+            return stats->txBytes;
+        case TX_PACKETS:
+            return stats->txPackets;
+        case TCP_RX_PACKETS:
+            return stats->tcpRxPackets;
+        case TCP_TX_PACKETS:
+            return stats->tcpTxPackets;
+        default:
+            return UNKNOWN;
+    }
+}
+
+static jlong getTotalStat(JNIEnv* env, jclass clazz, jint type) {
+    Stats stats = {};
+
+    if (bpfGetIfaceStats(NULL, &stats) == 0) {
+        return getStatsType(&stats, (StatsType) type);
+    } else {
+        return UNKNOWN;
+    }
+}
+
+static jlong getIfaceStat(JNIEnv* env, jclass clazz, jstring iface, jint type) {
+    ScopedUtfChars iface8(env, iface);
+    if (iface8.c_str() == NULL) {
+        return UNKNOWN;
+    }
+
+    Stats stats = {};
+
+    if (bpfGetIfaceStats(iface8.c_str(), &stats) == 0) {
+        return getStatsType(&stats, (StatsType) type);
+    } else {
+        return UNKNOWN;
+    }
+}
+
+static jlong getUidStat(JNIEnv* env, jclass clazz, jint uid, jint type) {
+    Stats stats = {};
+
+    if (bpfGetUidStats(uid, &stats) == 0) {
+        return getStatsType(&stats, (StatsType) type);
+    } else {
+        return UNKNOWN;
+    }
+}
+
+static const JNINativeMethod gMethods[] = {
+        {"nativeGetTotalStat", "(I)J", (void*)getTotalStat},
+        {"nativeGetIfaceStat", "(Ljava/lang/String;I)J", (void*)getIfaceStat},
+        {"nativeGetUidStat", "(II)J", (void*)getUidStat},
+};
+
+int register_android_server_net_NetworkStatsService(JNIEnv* env) {
+    return jniRegisterNativeMethods(env, "com/android/server/net/NetworkStatsService", gMethods,
+                                    NELEM(gMethods));
+}
+
+}
diff --git a/service-t/jni/onload.cpp b/service-t/jni/onload.cpp
new file mode 100644
index 0000000..bca4697
--- /dev/null
+++ b/service-t/jni/onload.cpp
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <nativehelper/JNIHelp.h>
+#include <log/log.h>
+
+namespace android {
+
+int register_com_android_net_module_util_BpfMap(JNIEnv* env, char const* class_name);
+
+extern "C" jint JNI_OnLoad(JavaVM* vm, void*) {
+    JNIEnv *env;
+    if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
+        ALOGE("GetEnv failed");
+        return JNI_ERR;
+    }
+
+    if (register_com_android_net_module_util_BpfMap(env,
+            "com/android/net/module/util/BpfMap") < 0) return JNI_ERR;
+
+    return JNI_VERSION_1_6;
+}
+
+};
+
diff --git a/service-t/src/com/android/server/INativeDaemonConnectorCallbacks.java b/service-t/src/com/android/server/INativeDaemonConnectorCallbacks.java
new file mode 100644
index 0000000..0cf9dcd
--- /dev/null
+++ b/service-t/src/com/android/server/INativeDaemonConnectorCallbacks.java
@@ -0,0 +1,25 @@
+
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+interface INativeDaemonConnectorCallbacks {
+
+    void onDaemonConnected();
+    boolean onCheckHoldWakeLock(int code);
+    boolean onEvent(int code, String raw, String[] cooked);
+}
diff --git a/service-t/src/com/android/server/IpSecService.java b/service-t/src/com/android/server/IpSecService.java
new file mode 100644
index 0000000..4bc40ea
--- /dev/null
+++ b/service-t/src/com/android/server/IpSecService.java
@@ -0,0 +1,1878 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import static android.Manifest.permission.DUMP;
+import static android.net.IpSecManager.INVALID_RESOURCE_ID;
+import static android.system.OsConstants.AF_INET;
+import static android.system.OsConstants.AF_INET6;
+import static android.system.OsConstants.AF_UNSPEC;
+import static android.system.OsConstants.EINVAL;
+import static android.system.OsConstants.IPPROTO_UDP;
+import static android.system.OsConstants.SOCK_DGRAM;
+
+import android.annotation.NonNull;
+import android.app.AppOpsManager;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.net.ConnectivityManager;
+import android.net.IIpSecService;
+import android.net.INetd;
+import android.net.InetAddresses;
+import android.net.IpSecAlgorithm;
+import android.net.IpSecConfig;
+import android.net.IpSecManager;
+import android.net.IpSecSpiResponse;
+import android.net.IpSecTransform;
+import android.net.IpSecTransformResponse;
+import android.net.IpSecTunnelInterfaceResponse;
+import android.net.IpSecUdpEncapResponse;
+import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.TrafficStats;
+import android.os.Binder;
+import android.os.IBinder;
+import android.os.ParcelFileDescriptor;
+import android.os.Process;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.system.ErrnoException;
+import android.system.Os;
+import android.system.OsConstants;
+import android.text.TextUtils;
+import android.util.Log;
+import android.util.Range;
+import android.util.SparseArray;
+import android.util.SparseBooleanArray;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.Preconditions;
+import com.android.net.module.util.BinderUtils;
+import com.android.net.module.util.NetdUtils;
+import com.android.net.module.util.PermissionUtils;
+
+import libcore.io.IoUtils;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A service to manage multiple clients that want to access the IpSec API. The service is
+ * responsible for maintaining a list of clients and managing the resources (and related quotas)
+ * that each of them own.
+ *
+ * <p>Synchronization in IpSecService is done on all entrypoints due to potential race conditions at
+ * the kernel/xfrm level. Further, this allows the simplifying assumption to be made that only one
+ * thread is ever running at a time.
+ *
+ * @hide
+ */
+public class IpSecService extends IIpSecService.Stub {
+    private static final String TAG = "IpSecService";
+    private static final boolean DBG = Log.isLoggable(TAG, Log.DEBUG);
+    private static final int[] ADDRESS_FAMILIES =
+            new int[] {OsConstants.AF_INET, OsConstants.AF_INET6};
+
+    private static final int NETD_FETCH_TIMEOUT_MS = 5000; // ms
+    private static final InetAddress INADDR_ANY;
+
+    @VisibleForTesting static final int MAX_PORT_BIND_ATTEMPTS = 10;
+
+    private final INetd mNetd;
+
+    static {
+        try {
+            INADDR_ANY = InetAddress.getByAddress(new byte[] {0, 0, 0, 0});
+        } catch (UnknownHostException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    static final int FREE_PORT_MIN = 1024; // ports 1-1023 are reserved
+    static final int PORT_MAX = 0xFFFF; // ports are an unsigned 16-bit integer
+
+    /* Binder context for this service */
+    private final Context mContext;
+    private final Dependencies mDeps;
+
+    /**
+     * The next non-repeating global ID for tracking resources between users, this service, and
+     * kernel data structures. Accessing this variable is not thread safe, so it is only read or
+     * modified within blocks synchronized on IpSecService.this. We want to avoid -1
+     * (INVALID_RESOURCE_ID) and 0 (we probably forgot to initialize it).
+     */
+    @GuardedBy("IpSecService.this")
+    private int mNextResourceId = 1;
+
+    /**
+     * Dependencies of IpSecService, for injection in tests.
+     */
+    @VisibleForTesting
+    public static class Dependencies {
+        /**
+         * Get a reference to INetd.
+         */
+        public INetd getNetdInstance(Context context) throws RemoteException {
+            final INetd netd = INetd.Stub.asInterface((IBinder)
+                    context.getSystemService(Context.NETD_SERVICE));
+            if (netd == null) {
+                throw new RemoteException("Failed to Get Netd Instance");
+            }
+            return netd;
+        }
+    }
+
+    final UidFdTagger mUidFdTagger;
+
+    /**
+     * Interface for user-reference and kernel-resource cleanup.
+     *
+     * <p>This interface must be implemented for a resource to be reference counted.
+     */
+    @VisibleForTesting
+    public interface IResource {
+        /**
+         * Invalidates a IResource object, ensuring it is invalid for the purposes of allocating new
+         * objects dependent on it.
+         *
+         * <p>Implementations of this method are expected to remove references to the IResource
+         * object from the IpSecService's tracking arrays. The removal from the arrays ensures that
+         * the resource is considered invalid for user access or allocation or use in other
+         * resources.
+         *
+         * <p>References to the IResource object may be held by other RefcountedResource objects,
+         * and as such, the underlying resources and quota may not be cleaned up.
+         */
+        void invalidate() throws RemoteException;
+
+        /**
+         * Releases underlying resources and related quotas.
+         *
+         * <p>Implementations of this method are expected to remove all system resources that are
+         * tracked by the IResource object. Due to other RefcountedResource objects potentially
+         * having references to the IResource object, freeUnderlyingResources may not always be
+         * called from releaseIfUnreferencedRecursively().
+         */
+        void freeUnderlyingResources() throws RemoteException;
+    }
+
+    /**
+     * RefcountedResource manages references and dependencies in an exclusively acyclic graph.
+     *
+     * <p>RefcountedResource implements both explicit and implicit resource management. Creating a
+     * RefcountedResource object creates an explicit reference that must be freed by calling
+     * userRelease(). Additionally, adding this object as a child of another RefcountedResource
+     * object will add an implicit reference.
+     *
+     * <p>Resources are cleaned up when all references, both implicit and explicit, are released
+     * (ie, when userRelease() is called and when all parents have called releaseReference() on this
+     * object.)
+     */
+    @VisibleForTesting
+    public class RefcountedResource<T extends IResource> implements IBinder.DeathRecipient {
+        private final T mResource;
+        private final List<RefcountedResource> mChildren;
+        int mRefCount = 1; // starts at 1 for user's reference.
+        IBinder mBinder;
+
+        RefcountedResource(T resource, IBinder binder, RefcountedResource... children) {
+            synchronized (IpSecService.this) {
+                this.mResource = resource;
+                this.mChildren = new ArrayList<>(children.length);
+                this.mBinder = binder;
+
+                for (RefcountedResource child : children) {
+                    mChildren.add(child);
+                    child.mRefCount++;
+                }
+
+                try {
+                    mBinder.linkToDeath(this, 0);
+                } catch (RemoteException e) {
+                    binderDied();
+                    e.rethrowFromSystemServer();
+                }
+            }
+        }
+
+        /**
+         * If the Binder object dies, this function is called to free the system resources that are
+         * being tracked by this record and to subsequently release this record for garbage
+         * collection
+         */
+        @Override
+        public void binderDied() {
+            synchronized (IpSecService.this) {
+                try {
+                    userRelease();
+                } catch (Exception e) {
+                    Log.e(TAG, "Failed to release resource: " + e);
+                }
+            }
+        }
+
+        public T getResource() {
+            return mResource;
+        }
+
+        /**
+         * Unlinks from binder and performs IpSecService resource cleanup (removes from resource
+         * arrays)
+         *
+         * <p>If this method has been previously called, the RefcountedResource's binder field will
+         * be null, and the method will return without performing the cleanup a second time.
+         *
+         * <p>Note that calling this function does not imply that kernel resources will be freed at
+         * this time, or that the related quota will be returned. Such actions will only be
+         * performed upon the reference count reaching zero.
+         */
+        @GuardedBy("IpSecService.this")
+        public void userRelease() throws RemoteException {
+            // Prevent users from putting reference counts into a bad state by calling
+            // userRelease() multiple times.
+            if (mBinder == null) {
+                return;
+            }
+
+            mBinder.unlinkToDeath(this, 0);
+            mBinder = null;
+
+            mResource.invalidate();
+
+            releaseReference();
+        }
+
+        /**
+         * Removes a reference to this resource. If the resultant reference count is zero, the
+         * underlying resources are freed, and references to all child resources are also dropped
+         * recursively (resulting in them freeing their resources and children, etcetera)
+         *
+         * <p>This method also sets the reference count to an invalid value (-1) to signify that it
+         * has been fully released. Any subsequent calls to this method will result in an
+         * IllegalStateException being thrown due to resource already having been previously
+         * released
+         */
+        @VisibleForTesting
+        @GuardedBy("IpSecService.this")
+        public void releaseReference() throws RemoteException {
+            mRefCount--;
+
+            if (mRefCount > 0) {
+                return;
+            } else if (mRefCount < 0) {
+                throw new IllegalStateException(
+                        "Invalid operation - resource has already been released.");
+            }
+
+            // Cleanup own resources
+            mResource.freeUnderlyingResources();
+
+            // Cleanup child resources as needed
+            for (RefcountedResource<? extends IResource> child : mChildren) {
+                child.releaseReference();
+            }
+
+            // Enforce that resource cleanup can only be called once
+            // By decrementing the refcount (from 0 to -1), the next call will throw an
+            // IllegalStateException - it has already been released fully.
+            mRefCount--;
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{mResource=")
+                    .append(mResource)
+                    .append(", mRefCount=")
+                    .append(mRefCount)
+                    .append(", mChildren=")
+                    .append(mChildren)
+                    .append("}")
+                    .toString();
+        }
+    }
+
+    /**
+     * Very simple counting class that looks much like a counting semaphore
+     *
+     * <p>This class is not thread-safe, and expects that that users of this class will ensure
+     * synchronization and thread safety by holding the IpSecService.this instance lock.
+     */
+    @VisibleForTesting
+    static class ResourceTracker {
+        private final int mMax;
+        int mCurrent;
+
+        ResourceTracker(int max) {
+            mMax = max;
+            mCurrent = 0;
+        }
+
+        boolean isAvailable() {
+            return (mCurrent < mMax);
+        }
+
+        void take() {
+            if (!isAvailable()) {
+                Log.wtf(TAG, "Too many resources allocated!");
+            }
+            mCurrent++;
+        }
+
+        void give() {
+            if (mCurrent <= 0) {
+                Log.wtf(TAG, "We've released this resource too many times");
+            }
+            mCurrent--;
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{mCurrent=")
+                    .append(mCurrent)
+                    .append(", mMax=")
+                    .append(mMax)
+                    .append("}")
+                    .toString();
+        }
+    }
+
+    @VisibleForTesting
+    static final class UserRecord {
+        /* Maximum number of each type of resource that a single UID may possess */
+
+        // Up to 4 active VPNs/IWLAN with potential soft handover.
+        public static final int MAX_NUM_TUNNEL_INTERFACES = 8;
+        public static final int MAX_NUM_ENCAP_SOCKETS = 16;
+
+        // SPIs and Transforms are both cheap, and are 1:1 correlated.
+        public static final int MAX_NUM_TRANSFORMS = 64;
+        public static final int MAX_NUM_SPIS = 64;
+
+        /**
+         * Store each of the OwnedResource types in an (thinly wrapped) sparse array for indexing
+         * and explicit (user) reference management.
+         *
+         * <p>These are stored in separate arrays to improve debuggability and dump output clarity.
+         *
+         * <p>Resources are removed from this array when the user releases their explicit reference
+         * by calling one of the releaseResource() methods.
+         */
+        final RefcountedResourceArray<SpiRecord> mSpiRecords =
+                new RefcountedResourceArray<>(SpiRecord.class.getSimpleName());
+        final RefcountedResourceArray<TransformRecord> mTransformRecords =
+                new RefcountedResourceArray<>(TransformRecord.class.getSimpleName());
+        final RefcountedResourceArray<EncapSocketRecord> mEncapSocketRecords =
+                new RefcountedResourceArray<>(EncapSocketRecord.class.getSimpleName());
+        final RefcountedResourceArray<TunnelInterfaceRecord> mTunnelInterfaceRecords =
+                new RefcountedResourceArray<>(TunnelInterfaceRecord.class.getSimpleName());
+
+        /**
+         * Trackers for quotas for each of the OwnedResource types.
+         *
+         * <p>These trackers are separate from the resource arrays, since they are incremented and
+         * decremented at different points in time. Specifically, quota is only returned upon final
+         * resource deallocation (after all explicit and implicit references are released). Note
+         * that it is possible that calls to releaseResource() will not return the used quota if
+         * there are other resources that depend on (are parents of) the resource being released.
+         */
+        final ResourceTracker mSpiQuotaTracker = new ResourceTracker(MAX_NUM_SPIS);
+        final ResourceTracker mTransformQuotaTracker = new ResourceTracker(MAX_NUM_TRANSFORMS);
+        final ResourceTracker mSocketQuotaTracker = new ResourceTracker(MAX_NUM_ENCAP_SOCKETS);
+        final ResourceTracker mTunnelQuotaTracker = new ResourceTracker(MAX_NUM_TUNNEL_INTERFACES);
+
+        void removeSpiRecord(int resourceId) {
+            mSpiRecords.remove(resourceId);
+        }
+
+        void removeTransformRecord(int resourceId) {
+            mTransformRecords.remove(resourceId);
+        }
+
+        void removeTunnelInterfaceRecord(int resourceId) {
+            mTunnelInterfaceRecords.remove(resourceId);
+        }
+
+        void removeEncapSocketRecord(int resourceId) {
+            mEncapSocketRecords.remove(resourceId);
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{mSpiQuotaTracker=")
+                    .append(mSpiQuotaTracker)
+                    .append(", mTransformQuotaTracker=")
+                    .append(mTransformQuotaTracker)
+                    .append(", mSocketQuotaTracker=")
+                    .append(mSocketQuotaTracker)
+                    .append(", mTunnelQuotaTracker=")
+                    .append(mTunnelQuotaTracker)
+                    .append(", mSpiRecords=")
+                    .append(mSpiRecords)
+                    .append(", mTransformRecords=")
+                    .append(mTransformRecords)
+                    .append(", mEncapSocketRecords=")
+                    .append(mEncapSocketRecords)
+                    .append(", mTunnelInterfaceRecords=")
+                    .append(mTunnelInterfaceRecords)
+                    .append("}")
+                    .toString();
+        }
+    }
+
+    /**
+     * This class is not thread-safe, and expects that that users of this class will ensure
+     * synchronization and thread safety by holding the IpSecService.this instance lock.
+     */
+    @VisibleForTesting
+    static final class UserResourceTracker {
+        private final SparseArray<UserRecord> mUserRecords = new SparseArray<>();
+
+        /** Lazy-initialization/getter that populates or retrieves the UserRecord as needed */
+        public UserRecord getUserRecord(int uid) {
+            checkCallerUid(uid);
+
+            UserRecord r = mUserRecords.get(uid);
+            if (r == null) {
+                r = new UserRecord();
+                mUserRecords.put(uid, r);
+            }
+            return r;
+        }
+
+        /** Safety method; guards against access of other user's UserRecords */
+        private void checkCallerUid(int uid) {
+            if (uid != Binder.getCallingUid() && Process.SYSTEM_UID != Binder.getCallingUid()) {
+                throw new SecurityException("Attempted access of unowned resources");
+            }
+        }
+
+        @Override
+        public String toString() {
+            return mUserRecords.toString();
+        }
+    }
+
+    @VisibleForTesting final UserResourceTracker mUserResourceTracker = new UserResourceTracker();
+
+    /**
+     * The OwnedResourceRecord class provides a facility to cleanly and reliably track system
+     * resources. It relies on a provided resourceId that should uniquely identify the kernel
+     * resource. To use this class, the user should implement the invalidate() and
+     * freeUnderlyingResources() methods that are responsible for cleaning up IpSecService resource
+     * tracking arrays and kernel resources, respectively.
+     *
+     * <p>This class associates kernel resources with the UID that owns and controls them.
+     */
+    private abstract class OwnedResourceRecord implements IResource {
+        final int mPid;
+        final int mUid;
+        protected final int mResourceId;
+
+        OwnedResourceRecord(int resourceId) {
+            super();
+            if (resourceId == INVALID_RESOURCE_ID) {
+                throw new IllegalArgumentException("Resource ID must not be INVALID_RESOURCE_ID");
+            }
+            mResourceId = resourceId;
+            mPid = Binder.getCallingPid();
+            mUid = Binder.getCallingUid();
+
+            getResourceTracker().take();
+        }
+
+        @Override
+        public abstract void invalidate() throws RemoteException;
+
+        /** Convenience method; retrieves the user resource record for the stored UID. */
+        protected UserRecord getUserRecord() {
+            return mUserResourceTracker.getUserRecord(mUid);
+        }
+
+        @Override
+        public abstract void freeUnderlyingResources() throws RemoteException;
+
+        /** Get the resource tracker for this resource */
+        protected abstract ResourceTracker getResourceTracker();
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{mResourceId=")
+                    .append(mResourceId)
+                    .append(", pid=")
+                    .append(mPid)
+                    .append(", uid=")
+                    .append(mUid)
+                    .append("}")
+                    .toString();
+        }
+    };
+
+    /**
+     * Thin wrapper over SparseArray to ensure resources exist, and simplify generic typing.
+     *
+     * <p>RefcountedResourceArray prevents null insertions, and throws an IllegalArgumentException
+     * if a key is not found during a retrieval process.
+     */
+    static class RefcountedResourceArray<T extends IResource> {
+        SparseArray<RefcountedResource<T>> mArray = new SparseArray<>();
+        private final String mTypeName;
+
+        RefcountedResourceArray(String typeName) {
+            this.mTypeName = typeName;
+        }
+
+        /**
+         * Accessor method to get inner resource object.
+         *
+         * @throws IllegalArgumentException if no resource with provided key is found.
+         */
+        T getResourceOrThrow(int key) {
+            return getRefcountedResourceOrThrow(key).getResource();
+        }
+
+        /**
+         * Accessor method to get reference counting wrapper.
+         *
+         * @throws IllegalArgumentException if no resource with provided key is found.
+         */
+        RefcountedResource<T> getRefcountedResourceOrThrow(int key) {
+            RefcountedResource<T> resource = mArray.get(key);
+            if (resource == null) {
+                throw new IllegalArgumentException(
+                        String.format("No such %s found for given id: %d", mTypeName, key));
+            }
+
+            return resource;
+        }
+
+        void put(int key, RefcountedResource<T> obj) {
+            Objects.requireNonNull(obj, "Null resources cannot be added");
+            mArray.put(key, obj);
+        }
+
+        void remove(int key) {
+            mArray.remove(key);
+        }
+
+        @Override
+        public String toString() {
+            return mArray.toString();
+        }
+    }
+
+    /**
+     * Tracks an SA in the kernel, and manages cleanup paths. Once a TransformRecord is
+     * created, the SpiRecord that originally tracked the SAs will reliquish the
+     * responsibility of freeing the underlying SA to this class via the mOwnedByTransform flag.
+     */
+    private final class TransformRecord extends OwnedResourceRecord {
+        private final IpSecConfig mConfig;
+        private final SpiRecord mSpi;
+        private final EncapSocketRecord mSocket;
+
+        TransformRecord(
+                int resourceId, IpSecConfig config, SpiRecord spi, EncapSocketRecord socket) {
+            super(resourceId);
+            mConfig = config;
+            mSpi = spi;
+            mSocket = socket;
+
+            spi.setOwnedByTransform();
+        }
+
+        public IpSecConfig getConfig() {
+            return mConfig;
+        }
+
+        public SpiRecord getSpiRecord() {
+            return mSpi;
+        }
+
+        public EncapSocketRecord getSocketRecord() {
+            return mSocket;
+        }
+
+        /** always guarded by IpSecService#this */
+        @Override
+        public void freeUnderlyingResources() {
+            int spi = mSpi.getSpi();
+            try {
+                mNetd.ipSecDeleteSecurityAssociation(
+                        mUid,
+                        mConfig.getSourceAddress(),
+                        mConfig.getDestinationAddress(),
+                        spi,
+                        mConfig.getMarkValue(),
+                        mConfig.getMarkMask(),
+                        mConfig.getXfrmInterfaceId());
+            } catch (RemoteException | ServiceSpecificException e) {
+                Log.e(TAG, "Failed to delete SA with ID: " + mResourceId, e);
+            }
+
+            getResourceTracker().give();
+        }
+
+        @Override
+        public void invalidate() throws RemoteException {
+            getUserRecord().removeTransformRecord(mResourceId);
+        }
+
+        @Override
+        protected ResourceTracker getResourceTracker() {
+            return getUserRecord().mTransformQuotaTracker;
+        }
+
+        @Override
+        public String toString() {
+            StringBuilder strBuilder = new StringBuilder();
+            strBuilder
+                    .append("{super=")
+                    .append(super.toString())
+                    .append(", mSocket=")
+                    .append(mSocket)
+                    .append(", mSpi.mResourceId=")
+                    .append(mSpi.mResourceId)
+                    .append(", mConfig=")
+                    .append(mConfig)
+                    .append("}");
+            return strBuilder.toString();
+        }
+    }
+
+    /**
+     * Tracks a single SA in the kernel, and manages cleanup paths. Once used in a Transform, the
+     * responsibility for cleaning up underlying resources will be passed to the TransformRecord
+     * object
+     */
+    private final class SpiRecord extends OwnedResourceRecord {
+        private final String mSourceAddress;
+        private final String mDestinationAddress;
+        private int mSpi;
+
+        private boolean mOwnedByTransform = false;
+
+        SpiRecord(int resourceId, String sourceAddress,
+                String destinationAddress, int spi) {
+            super(resourceId);
+            mSourceAddress = sourceAddress;
+            mDestinationAddress = destinationAddress;
+            mSpi = spi;
+        }
+
+        /** always guarded by IpSecService#this */
+        @Override
+        public void freeUnderlyingResources() {
+            try {
+                if (!mOwnedByTransform) {
+                    mNetd.ipSecDeleteSecurityAssociation(
+                            mUid, mSourceAddress, mDestinationAddress, mSpi, 0 /* mark */,
+                            0 /* mask */, 0 /* if_id */);
+                }
+            } catch (ServiceSpecificException | RemoteException e) {
+                Log.e(TAG, "Failed to delete SPI reservation with ID: " + mResourceId, e);
+            }
+
+            mSpi = IpSecManager.INVALID_SECURITY_PARAMETER_INDEX;
+
+            getResourceTracker().give();
+        }
+
+        public int getSpi() {
+            return mSpi;
+        }
+
+        public String getDestinationAddress() {
+            return mDestinationAddress;
+        }
+
+        public void setOwnedByTransform() {
+            if (mOwnedByTransform) {
+                // Programming error
+                throw new IllegalStateException("Cannot own an SPI twice!");
+            }
+
+            mOwnedByTransform = true;
+        }
+
+        public boolean getOwnedByTransform() {
+            return mOwnedByTransform;
+        }
+
+        @Override
+        public void invalidate() throws RemoteException {
+            getUserRecord().removeSpiRecord(mResourceId);
+        }
+
+        @Override
+        protected ResourceTracker getResourceTracker() {
+            return getUserRecord().mSpiQuotaTracker;
+        }
+
+        @Override
+        public String toString() {
+            StringBuilder strBuilder = new StringBuilder();
+            strBuilder
+                    .append("{super=")
+                    .append(super.toString())
+                    .append(", mSpi=")
+                    .append(mSpi)
+                    .append(", mSourceAddress=")
+                    .append(mSourceAddress)
+                    .append(", mDestinationAddress=")
+                    .append(mDestinationAddress)
+                    .append(", mOwnedByTransform=")
+                    .append(mOwnedByTransform)
+                    .append("}");
+            return strBuilder.toString();
+        }
+    }
+
+    private final SparseBooleanArray mTunnelNetIds = new SparseBooleanArray();
+    final Range<Integer> mNetIdRange = ConnectivityManager.getIpSecNetIdRange();
+    private int mNextTunnelNetId = mNetIdRange.getLower();
+
+    /**
+     * Reserves a netId within the range of netIds allocated for IPsec tunnel interfaces
+     *
+     * <p>This method should only be called from Binder threads. Do not call this from within the
+     * system server as it will crash the system on failure.
+     *
+     * @return an integer key within the netId range, if successful
+     * @throws IllegalStateException if unsuccessful (all netId are currently reserved)
+     */
+    @VisibleForTesting
+    int reserveNetId() {
+        final int range = mNetIdRange.getUpper() - mNetIdRange.getLower() + 1;
+        synchronized (mTunnelNetIds) {
+            for (int i = 0; i < range; i++) {
+                final int netId = mNextTunnelNetId;
+                if (++mNextTunnelNetId > mNetIdRange.getUpper()) {
+                    mNextTunnelNetId = mNetIdRange.getLower();
+                }
+                if (!mTunnelNetIds.get(netId)) {
+                    mTunnelNetIds.put(netId, true);
+                    return netId;
+                }
+            }
+        }
+        throw new IllegalStateException("No free netIds to allocate");
+    }
+
+    @VisibleForTesting
+    void releaseNetId(int netId) {
+        synchronized (mTunnelNetIds) {
+            mTunnelNetIds.delete(netId);
+        }
+    }
+
+    /**
+     * Tracks an tunnel interface, and manages cleanup paths.
+     *
+     * <p>This class is not thread-safe, and expects that that users of this class will ensure
+     * synchronization and thread safety by holding the IpSecService.this instance lock
+     */
+    @VisibleForTesting
+    final class TunnelInterfaceRecord extends OwnedResourceRecord {
+        private final String mInterfaceName;
+
+        // outer addresses
+        private final String mLocalAddress;
+        private final String mRemoteAddress;
+
+        private final int mIkey;
+        private final int mOkey;
+
+        private final int mIfId;
+
+        private Network mUnderlyingNetwork;
+
+        TunnelInterfaceRecord(
+                int resourceId,
+                String interfaceName,
+                Network underlyingNetwork,
+                String localAddr,
+                String remoteAddr,
+                int ikey,
+                int okey,
+                int intfId) {
+            super(resourceId);
+
+            mInterfaceName = interfaceName;
+            mUnderlyingNetwork = underlyingNetwork;
+            mLocalAddress = localAddr;
+            mRemoteAddress = remoteAddr;
+            mIkey = ikey;
+            mOkey = okey;
+            mIfId = intfId;
+        }
+
+        /** always guarded by IpSecService#this */
+        @Override
+        public void freeUnderlyingResources() {
+            // Calls to netd
+            //       Teardown VTI
+            //       Delete global policies
+            try {
+                mNetd.ipSecRemoveTunnelInterface(mInterfaceName);
+
+                for (int selAddrFamily : ADDRESS_FAMILIES) {
+                    mNetd.ipSecDeleteSecurityPolicy(
+                            mUid,
+                            selAddrFamily,
+                            IpSecManager.DIRECTION_OUT,
+                            mOkey,
+                            0xffffffff,
+                            mIfId);
+                    mNetd.ipSecDeleteSecurityPolicy(
+                            mUid,
+                            selAddrFamily,
+                            IpSecManager.DIRECTION_IN,
+                            mIkey,
+                            0xffffffff,
+                            mIfId);
+                }
+            } catch (ServiceSpecificException | RemoteException e) {
+                Log.e(
+                        TAG,
+                        "Failed to delete VTI with interface name: "
+                                + mInterfaceName
+                                + " and id: "
+                                + mResourceId, e);
+            }
+
+            getResourceTracker().give();
+            releaseNetId(mIkey);
+            releaseNetId(mOkey);
+        }
+
+        @GuardedBy("IpSecService.this")
+        public void setUnderlyingNetwork(Network underlyingNetwork) {
+            // When #applyTunnelModeTransform is called, this new underlying network will be used to
+            // update the output mark of the input transform.
+            mUnderlyingNetwork = underlyingNetwork;
+        }
+
+        @GuardedBy("IpSecService.this")
+        public Network getUnderlyingNetwork() {
+            return mUnderlyingNetwork;
+        }
+
+        public String getInterfaceName() {
+            return mInterfaceName;
+        }
+
+        /** Returns the local, outer address for the tunnelInterface */
+        public String getLocalAddress() {
+            return mLocalAddress;
+        }
+
+        /** Returns the remote, outer address for the tunnelInterface */
+        public String getRemoteAddress() {
+            return mRemoteAddress;
+        }
+
+        public int getIkey() {
+            return mIkey;
+        }
+
+        public int getOkey() {
+            return mOkey;
+        }
+
+        public int getIfId() {
+            return mIfId;
+        }
+
+        @Override
+        protected ResourceTracker getResourceTracker() {
+            return getUserRecord().mTunnelQuotaTracker;
+        }
+
+        @Override
+        public void invalidate() {
+            getUserRecord().removeTunnelInterfaceRecord(mResourceId);
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{super=")
+                    .append(super.toString())
+                    .append(", mInterfaceName=")
+                    .append(mInterfaceName)
+                    .append(", mUnderlyingNetwork=")
+                    .append(mUnderlyingNetwork)
+                    .append(", mLocalAddress=")
+                    .append(mLocalAddress)
+                    .append(", mRemoteAddress=")
+                    .append(mRemoteAddress)
+                    .append(", mIkey=")
+                    .append(mIkey)
+                    .append(", mOkey=")
+                    .append(mOkey)
+                    .append("}")
+                    .toString();
+        }
+    }
+
+    /**
+     * Tracks a UDP encap socket, and manages cleanup paths
+     *
+     * <p>While this class does not manage non-kernel resources, race conditions around socket
+     * binding require that the service creates the encap socket, binds it and applies the socket
+     * policy before handing it to a user.
+     */
+    private final class EncapSocketRecord extends OwnedResourceRecord {
+        private FileDescriptor mSocket;
+        private final int mPort;
+
+        EncapSocketRecord(int resourceId, FileDescriptor socket, int port) {
+            super(resourceId);
+            mSocket = socket;
+            mPort = port;
+        }
+
+        /** always guarded by IpSecService#this */
+        @Override
+        public void freeUnderlyingResources() {
+            Log.d(TAG, "Closing port " + mPort);
+            IoUtils.closeQuietly(mSocket);
+            mSocket = null;
+
+            getResourceTracker().give();
+        }
+
+        public int getPort() {
+            return mPort;
+        }
+
+        public FileDescriptor getFileDescriptor() {
+            return mSocket;
+        }
+
+        @Override
+        protected ResourceTracker getResourceTracker() {
+            return getUserRecord().mSocketQuotaTracker;
+        }
+
+        @Override
+        public void invalidate() {
+            getUserRecord().removeEncapSocketRecord(mResourceId);
+        }
+
+        @Override
+        public String toString() {
+            return new StringBuilder()
+                    .append("{super=")
+                    .append(super.toString())
+                    .append(", mSocket=")
+                    .append(mSocket)
+                    .append(", mPort=")
+                    .append(mPort)
+                    .append("}")
+                    .toString();
+        }
+    }
+
+    /**
+     * Constructs a new IpSecService instance
+     *
+     * @param context Binder context for this service
+     */
+    public IpSecService(Context context) {
+        this(context, new Dependencies());
+    }
+
+    @NonNull
+    private AppOpsManager getAppOpsManager() {
+        AppOpsManager appOps = (AppOpsManager) mContext.getSystemService(Context.APP_OPS_SERVICE);
+        if (appOps == null) throw new RuntimeException("System Server couldn't get AppOps");
+        return appOps;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public IpSecService(Context context, Dependencies deps) {
+        this(
+                context,
+                deps,
+                (fd, uid) -> {
+                    try {
+                        TrafficStats.setThreadStatsUid(uid);
+                        TrafficStats.tagFileDescriptor(fd);
+                    } finally {
+                        TrafficStats.clearThreadStatsUid();
+                    }
+                });
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public IpSecService(Context context, Dependencies deps, UidFdTagger uidFdTagger) {
+        mContext = context;
+        mDeps = Objects.requireNonNull(deps, "Missing dependencies.");
+        mUidFdTagger = uidFdTagger;
+        try {
+            mNetd = mDeps.getNetdInstance(mContext);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Checks that the provided InetAddress is valid for use in an IPsec SA. The address must not be
+     * a wildcard address and must be in a numeric form such as 1.2.3.4 or 2001::1.
+     */
+    private static void checkInetAddress(String inetAddress) {
+        if (TextUtils.isEmpty(inetAddress)) {
+            throw new IllegalArgumentException("Unspecified address");
+        }
+
+        InetAddress checkAddr = InetAddresses.parseNumericAddress(inetAddress);
+
+        if (checkAddr.isAnyLocalAddress()) {
+            throw new IllegalArgumentException("Inappropriate wildcard address: " + inetAddress);
+        }
+    }
+
+    /**
+     * Checks the user-provided direction field and throws an IllegalArgumentException if it is not
+     * DIRECTION_IN or DIRECTION_OUT
+     */
+    private void checkDirection(int direction) {
+        switch (direction) {
+            case IpSecManager.DIRECTION_OUT:
+            case IpSecManager.DIRECTION_IN:
+                return;
+            case IpSecManager.DIRECTION_FWD:
+                // Only NETWORK_STACK or MAINLINE_NETWORK_STACK allowed to use forward policies
+                PermissionUtils.enforceNetworkStackPermission(mContext);
+                return;
+        }
+        throw new IllegalArgumentException("Invalid Direction: " + direction);
+    }
+
+    /** Get a new SPI and maintain the reservation in the system server */
+    @Override
+    public synchronized IpSecSpiResponse allocateSecurityParameterIndex(
+            String destinationAddress, int requestedSpi, IBinder binder) throws RemoteException {
+        checkInetAddress(destinationAddress);
+        // RFC 4303 Section 2.1 - 0=local, 1-255=reserved.
+        if (requestedSpi > 0 && requestedSpi < 256) {
+            throw new IllegalArgumentException("ESP SPI must not be in the range of 0-255.");
+        }
+        Objects.requireNonNull(binder, "Null Binder passed to allocateSecurityParameterIndex");
+
+        int callingUid = Binder.getCallingUid();
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(callingUid);
+        final int resourceId = mNextResourceId++;
+
+        int spi = IpSecManager.INVALID_SECURITY_PARAMETER_INDEX;
+        try {
+            if (!userRecord.mSpiQuotaTracker.isAvailable()) {
+                return new IpSecSpiResponse(
+                        IpSecManager.Status.RESOURCE_UNAVAILABLE, INVALID_RESOURCE_ID, spi);
+            }
+
+            spi = mNetd.ipSecAllocateSpi(callingUid, "", destinationAddress, requestedSpi);
+            Log.d(TAG, "Allocated SPI " + spi);
+            userRecord.mSpiRecords.put(
+                    resourceId,
+                    new RefcountedResource<SpiRecord>(
+                            new SpiRecord(resourceId, "",
+                            destinationAddress, spi), binder));
+        } catch (ServiceSpecificException e) {
+            if (e.errorCode == OsConstants.ENOENT) {
+                return new IpSecSpiResponse(
+                        IpSecManager.Status.SPI_UNAVAILABLE, INVALID_RESOURCE_ID, spi);
+            }
+            throw e;
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+        return new IpSecSpiResponse(IpSecManager.Status.OK, resourceId, spi);
+    }
+
+    /* This method should only be called from Binder threads. Do not call this from
+     * within the system server as it will crash the system on failure.
+     */
+    private void releaseResource(RefcountedResourceArray resArray, int resourceId)
+            throws RemoteException {
+        resArray.getRefcountedResourceOrThrow(resourceId).userRelease();
+    }
+
+    /** Release a previously allocated SPI that has been registered with the system server */
+    @Override
+    public synchronized void releaseSecurityParameterIndex(int resourceId) throws RemoteException {
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        releaseResource(userRecord.mSpiRecords, resourceId);
+    }
+
+    /**
+     * This function finds and forcibly binds to a random system port, ensuring that the port cannot
+     * be unbound.
+     *
+     * <p>A socket cannot be un-bound from a port if it was bound to that port by number. To select
+     * a random open port and then bind by number, this function creates a temp socket, binds to a
+     * random port (specifying 0), gets that port number, and then uses is to bind the user's UDP
+     * Encapsulation Socket forcibly, so that it cannot be un-bound by the user with the returned
+     * FileHandle.
+     *
+     * <p>The loop in this function handles the inherent race window between un-binding to a port
+     * and re-binding, during which the system could *technically* hand that port out to someone
+     * else.
+     */
+    private int bindToRandomPort(FileDescriptor sockFd) throws IOException {
+        for (int i = MAX_PORT_BIND_ATTEMPTS; i > 0; i--) {
+            try {
+                FileDescriptor probeSocket = Os.socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+                Os.bind(probeSocket, INADDR_ANY, 0);
+                int port = ((InetSocketAddress) Os.getsockname(probeSocket)).getPort();
+                Os.close(probeSocket);
+                Log.v(TAG, "Binding to port " + port);
+                Os.bind(sockFd, INADDR_ANY, port);
+                return port;
+            } catch (ErrnoException e) {
+                // Someone miraculously claimed the port just after we closed probeSocket.
+                if (e.errno == OsConstants.EADDRINUSE) {
+                    continue;
+                }
+                throw e.rethrowAsIOException();
+            }
+        }
+        throw new IOException("Failed " + MAX_PORT_BIND_ATTEMPTS + " attempts to bind to a port");
+    }
+
+    /**
+     * Functional interface to do traffic tagging of given sockets to UIDs.
+     *
+     * <p>Specifically used by openUdpEncapsulationSocket to ensure data usage on the UDP encap
+     * sockets are billed to the UID that the UDP encap socket was created on behalf of.
+     *
+     * <p>Separate class so that the socket tagging logic can be mocked; TrafficStats uses static
+     * methods that cannot be easily mocked/tested.
+     */
+    @VisibleForTesting
+    public interface UidFdTagger {
+        /**
+         * Sets socket tag to assign all traffic to the provided UID.
+         *
+         * <p>Since the socket is created on behalf of an unprivileged application, all traffic
+         * should be accounted to the UID of the unprivileged application.
+         */
+        void tag(FileDescriptor fd, int uid) throws IOException;
+    }
+
+    /**
+     * Open a socket via the system server and bind it to the specified port (random if port=0).
+     * This will return a PFD to the user that represent a bound UDP socket. The system server will
+     * cache the socket and a record of its owner so that it can and must be freed when no longer
+     * needed.
+     */
+    @Override
+    public synchronized IpSecUdpEncapResponse openUdpEncapsulationSocket(int port, IBinder binder)
+            throws RemoteException {
+        if (port != 0 && (port < FREE_PORT_MIN || port > PORT_MAX)) {
+            throw new IllegalArgumentException(
+                    "Specified port number must be a valid non-reserved UDP port");
+        }
+        Objects.requireNonNull(binder, "Null Binder passed to openUdpEncapsulationSocket");
+
+        int callingUid = Binder.getCallingUid();
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(callingUid);
+        final int resourceId = mNextResourceId++;
+
+        ParcelFileDescriptor pFd = null;
+        try {
+            if (!userRecord.mSocketQuotaTracker.isAvailable()) {
+                return new IpSecUdpEncapResponse(IpSecManager.Status.RESOURCE_UNAVAILABLE);
+            }
+
+            FileDescriptor sockFd = null;
+            try {
+                sockFd = Os.socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+                pFd = ParcelFileDescriptor.dup(sockFd);
+            } finally {
+                IoUtils.closeQuietly(sockFd);
+            }
+
+            mUidFdTagger.tag(pFd.getFileDescriptor(), callingUid);
+            // This code is common to both the unspecified and specified port cases
+            Os.setsockoptInt(
+                    pFd.getFileDescriptor(),
+                    OsConstants.IPPROTO_UDP,
+                    OsConstants.UDP_ENCAP,
+                    OsConstants.UDP_ENCAP_ESPINUDP);
+
+            mNetd.ipSecSetEncapSocketOwner(pFd, callingUid);
+            if (port != 0) {
+                Log.v(TAG, "Binding to port " + port);
+                Os.bind(pFd.getFileDescriptor(), INADDR_ANY, port);
+            } else {
+                port = bindToRandomPort(pFd.getFileDescriptor());
+            }
+
+            userRecord.mEncapSocketRecords.put(
+                    resourceId,
+                    new RefcountedResource<EncapSocketRecord>(
+                            new EncapSocketRecord(resourceId, pFd.getFileDescriptor(), port),
+                            binder));
+            return new IpSecUdpEncapResponse(IpSecManager.Status.OK, resourceId, port,
+                    pFd.getFileDescriptor());
+        } catch (IOException | ErrnoException e) {
+            try {
+                if (pFd != null) {
+                    pFd.close();
+                }
+            } catch (IOException ex) {
+                // Nothing can be done at this point
+                Log.e(TAG, "Failed to close pFd.");
+            }
+        }
+        // If we make it to here, then something has gone wrong and we couldn't open a socket.
+        // The only reasonable condition that would cause that is resource unavailable.
+        return new IpSecUdpEncapResponse(IpSecManager.Status.RESOURCE_UNAVAILABLE);
+    }
+
+    /** close a socket that has been been allocated by and registered with the system server */
+    @Override
+    public synchronized void closeUdpEncapsulationSocket(int resourceId) throws RemoteException {
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        releaseResource(userRecord.mEncapSocketRecords, resourceId);
+    }
+
+    /**
+     * Create a tunnel interface for use in IPSec tunnel mode. The system server will cache the
+     * tunnel interface and a record of its owner so that it can and must be freed when no longer
+     * needed.
+     */
+    @Override
+    public synchronized IpSecTunnelInterfaceResponse createTunnelInterface(
+            String localAddr, String remoteAddr, Network underlyingNetwork, IBinder binder,
+            String callingPackage) {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+        Objects.requireNonNull(binder, "Null Binder passed to createTunnelInterface");
+        Objects.requireNonNull(underlyingNetwork, "No underlying network was specified");
+        checkInetAddress(localAddr);
+        checkInetAddress(remoteAddr);
+
+        // TODO: Check that underlying network exists, and IP addresses not assigned to a different
+        //       network (b/72316676).
+
+        int callerUid = Binder.getCallingUid();
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(callerUid);
+        if (!userRecord.mTunnelQuotaTracker.isAvailable()) {
+            return new IpSecTunnelInterfaceResponse(IpSecManager.Status.RESOURCE_UNAVAILABLE);
+        }
+
+        final int resourceId = mNextResourceId++;
+        final int ikey = reserveNetId();
+        final int okey = reserveNetId();
+        String intfName = String.format("%s%d", INetd.IPSEC_INTERFACE_PREFIX, resourceId);
+
+        try {
+            // Calls to netd:
+            //       Create VTI
+            //       Add inbound/outbound global policies
+            //              (use reqid = 0)
+            mNetd.ipSecAddTunnelInterface(intfName, localAddr, remoteAddr, ikey, okey, resourceId);
+
+            BinderUtils.withCleanCallingIdentity(() -> {
+                NetdUtils.setInterfaceUp(mNetd, intfName);
+            });
+
+            for (int selAddrFamily : ADDRESS_FAMILIES) {
+                // Always send down correct local/remote addresses for template.
+                mNetd.ipSecAddSecurityPolicy(
+                        callerUid,
+                        selAddrFamily,
+                        IpSecManager.DIRECTION_OUT,
+                        localAddr,
+                        remoteAddr,
+                        0,
+                        okey,
+                        0xffffffff,
+                        resourceId);
+                mNetd.ipSecAddSecurityPolicy(
+                        callerUid,
+                        selAddrFamily,
+                        IpSecManager.DIRECTION_IN,
+                        remoteAddr,
+                        localAddr,
+                        0,
+                        ikey,
+                        0xffffffff,
+                        resourceId);
+
+                // Add a forwarding policy on the tunnel interface. In order to support forwarding
+                // the IpSecTunnelInterface must have a forwarding policy matching the incoming SA.
+                //
+                // Unless a IpSecTransform is also applied against this interface in DIRECTION_FWD,
+                // forwarding will be blocked by default (as would be the case if this policy was
+                // absent).
+                //
+                // This is necessary only on the tunnel interface, and not any the interface to
+                // which traffic will be forwarded to.
+                mNetd.ipSecAddSecurityPolicy(
+                        callerUid,
+                        selAddrFamily,
+                        IpSecManager.DIRECTION_FWD,
+                        remoteAddr,
+                        localAddr,
+                        0,
+                        ikey,
+                        0xffffffff,
+                        resourceId);
+            }
+
+            userRecord.mTunnelInterfaceRecords.put(
+                    resourceId,
+                    new RefcountedResource<TunnelInterfaceRecord>(
+                            new TunnelInterfaceRecord(
+                                    resourceId,
+                                    intfName,
+                                    underlyingNetwork,
+                                    localAddr,
+                                    remoteAddr,
+                                    ikey,
+                                    okey,
+                                    resourceId),
+                            binder));
+            return new IpSecTunnelInterfaceResponse(IpSecManager.Status.OK, resourceId, intfName);
+        } catch (RemoteException e) {
+            // Release keys if we got an error.
+            releaseNetId(ikey);
+            releaseNetId(okey);
+            throw e.rethrowFromSystemServer();
+        } catch (Throwable t) {
+            // Release keys if we got an error.
+            releaseNetId(ikey);
+            releaseNetId(okey);
+            throw t;
+        }
+    }
+
+    /**
+     * Adds a new local address to the tunnel interface. This allows packets to be sent and received
+     * from multiple local IP addresses over the same tunnel.
+     */
+    @Override
+    public synchronized void addAddressToTunnelInterface(
+            int tunnelResourceId, LinkAddress localAddr, String callingPackage) {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+
+        // Get tunnelInterface record; if no such interface is found, will throw
+        // IllegalArgumentException
+        TunnelInterfaceRecord tunnelInterfaceInfo =
+                userRecord.mTunnelInterfaceRecords.getResourceOrThrow(tunnelResourceId);
+
+        try {
+            // We can assume general validity of the IP address, since we get them as a
+            // LinkAddress, which does some validation.
+            mNetd.interfaceAddAddress(
+                    tunnelInterfaceInfo.mInterfaceName,
+                    localAddr.getAddress().getHostAddress(),
+                    localAddr.getPrefixLength());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Remove a new local address from the tunnel interface. After removal, the address will no
+     * longer be available to send from, or receive on.
+     */
+    @Override
+    public synchronized void removeAddressFromTunnelInterface(
+            int tunnelResourceId, LinkAddress localAddr, String callingPackage) {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        // Get tunnelInterface record; if no such interface is found, will throw
+        // IllegalArgumentException
+        TunnelInterfaceRecord tunnelInterfaceInfo =
+                userRecord.mTunnelInterfaceRecords.getResourceOrThrow(tunnelResourceId);
+
+        try {
+            // We can assume general validity of the IP address, since we get them as a
+            // LinkAddress, which does some validation.
+            mNetd.interfaceDelAddress(
+                            tunnelInterfaceInfo.mInterfaceName,
+                            localAddr.getAddress().getHostAddress(),
+                            localAddr.getPrefixLength());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** Set TunnelInterface to use a specific underlying network. */
+    @Override
+    public synchronized void setNetworkForTunnelInterface(
+            int tunnelResourceId, Network underlyingNetwork, String callingPackage) {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+        Objects.requireNonNull(underlyingNetwork, "No underlying network was specified");
+
+        final UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+
+        // Get tunnelInterface record; if no such interface is found, will throw
+        // IllegalArgumentException. userRecord.mTunnelInterfaceRecords is never null
+        final TunnelInterfaceRecord tunnelInterfaceInfo =
+                userRecord.mTunnelInterfaceRecords.getResourceOrThrow(tunnelResourceId);
+
+        final ConnectivityManager connectivityManager =
+                mContext.getSystemService(ConnectivityManager.class);
+        final LinkProperties lp = connectivityManager.getLinkProperties(underlyingNetwork);
+        if (tunnelInterfaceInfo.getInterfaceName().equals(lp.getInterfaceName())) {
+            throw new IllegalArgumentException(
+                    "Underlying network cannot be the network being exposed by this tunnel");
+        }
+
+        // It is meaningless to check if the network exists or is valid because the network might
+        // disconnect at any time after it passes the check.
+
+        tunnelInterfaceInfo.setUnderlyingNetwork(underlyingNetwork);
+    }
+
+    /**
+     * Delete a TunnelInterface that has been been allocated by and registered with the system
+     * server
+     */
+    @Override
+    public synchronized void deleteTunnelInterface(
+            int resourceId, String callingPackage) throws RemoteException {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        releaseResource(userRecord.mTunnelInterfaceRecords, resourceId);
+    }
+
+    @VisibleForTesting
+    void validateAlgorithms(IpSecConfig config) throws IllegalArgumentException {
+        IpSecAlgorithm auth = config.getAuthentication();
+        IpSecAlgorithm crypt = config.getEncryption();
+        IpSecAlgorithm aead = config.getAuthenticatedEncryption();
+
+        // Validate the algorithm set
+        Preconditions.checkArgument(
+                aead != null || crypt != null || auth != null,
+                "No Encryption or Authentication algorithms specified");
+        Preconditions.checkArgument(
+                auth == null || auth.isAuthentication(),
+                "Unsupported algorithm for Authentication");
+        Preconditions.checkArgument(
+                crypt == null || crypt.isEncryption(), "Unsupported algorithm for Encryption");
+        Preconditions.checkArgument(
+                aead == null || aead.isAead(),
+                "Unsupported algorithm for Authenticated Encryption");
+        Preconditions.checkArgument(
+                aead == null || (auth == null && crypt == null),
+                "Authenticated Encryption is mutually exclusive with other Authentication "
+                        + "or Encryption algorithms");
+    }
+
+    private int getFamily(String inetAddress) {
+        int family = AF_UNSPEC;
+        InetAddress checkAddress = InetAddresses.parseNumericAddress(inetAddress);
+        if (checkAddress instanceof Inet4Address) {
+            family = AF_INET;
+        } else if (checkAddress instanceof Inet6Address) {
+            family = AF_INET6;
+        }
+        return family;
+    }
+
+    /**
+     * Checks an IpSecConfig parcel to ensure that the contents are valid and throws an
+     * IllegalArgumentException if they are not.
+     */
+    private void checkIpSecConfig(IpSecConfig config) {
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+
+        switch (config.getEncapType()) {
+            case IpSecTransform.ENCAP_NONE:
+                break;
+            case IpSecTransform.ENCAP_ESPINUDP:
+            case IpSecTransform.ENCAP_ESPINUDP_NON_IKE:
+                // Retrieve encap socket record; will throw IllegalArgumentException if not found
+                userRecord.mEncapSocketRecords.getResourceOrThrow(
+                        config.getEncapSocketResourceId());
+
+                int port = config.getEncapRemotePort();
+                if (port <= 0 || port > 0xFFFF) {
+                    throw new IllegalArgumentException("Invalid remote UDP port: " + port);
+                }
+                break;
+            default:
+                throw new IllegalArgumentException("Invalid Encap Type: " + config.getEncapType());
+        }
+
+        validateAlgorithms(config);
+
+        // Retrieve SPI record; will throw IllegalArgumentException if not found
+        SpiRecord s = userRecord.mSpiRecords.getResourceOrThrow(config.getSpiResourceId());
+
+        // Check to ensure that SPI has not already been used.
+        if (s.getOwnedByTransform()) {
+            throw new IllegalStateException("SPI already in use; cannot be used in new Transforms");
+        }
+
+        // If no remote address is supplied, then use one from the SPI.
+        if (TextUtils.isEmpty(config.getDestinationAddress())) {
+            config.setDestinationAddress(s.getDestinationAddress());
+        }
+
+        // All remote addresses must match
+        if (!config.getDestinationAddress().equals(s.getDestinationAddress())) {
+            throw new IllegalArgumentException("Mismatched remote addresseses.");
+        }
+
+        // This check is technically redundant due to the chain of custody between the SPI and
+        // the IpSecConfig, but in the future if the dest is allowed to be set explicitly in
+        // the transform, this will prevent us from messing up.
+        checkInetAddress(config.getDestinationAddress());
+
+        // Require a valid source address for all transforms.
+        checkInetAddress(config.getSourceAddress());
+
+        // Check to ensure source and destination have the same address family.
+        String sourceAddress = config.getSourceAddress();
+        String destinationAddress = config.getDestinationAddress();
+        int sourceFamily = getFamily(sourceAddress);
+        int destinationFamily = getFamily(destinationAddress);
+        if (sourceFamily != destinationFamily) {
+            throw new IllegalArgumentException(
+                    "Source address ("
+                            + sourceAddress
+                            + ") and destination address ("
+                            + destinationAddress
+                            + ") have different address families.");
+        }
+
+        // Throw an error if UDP Encapsulation is not used in IPv4.
+        if (config.getEncapType() != IpSecTransform.ENCAP_NONE && sourceFamily != AF_INET) {
+            throw new IllegalArgumentException(
+                    "UDP Encapsulation is not supported for this address family");
+        }
+
+        switch (config.getMode()) {
+            case IpSecTransform.MODE_TRANSPORT:
+                break;
+            case IpSecTransform.MODE_TUNNEL:
+                break;
+            default:
+                throw new IllegalArgumentException(
+                        "Invalid IpSecTransform.mode: " + config.getMode());
+        }
+
+        config.setMarkValue(0);
+        config.setMarkMask(0);
+    }
+
+    private static final String TUNNEL_OP = AppOpsManager.OPSTR_MANAGE_IPSEC_TUNNELS;
+
+    private void enforceTunnelFeatureAndPermissions(String callingPackage) {
+        if (!mContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_IPSEC_TUNNELS)) {
+            throw new UnsupportedOperationException(
+                    "IPsec Tunnel Mode requires PackageManager.FEATURE_IPSEC_TUNNELS");
+        }
+
+        Objects.requireNonNull(callingPackage, "Null calling package cannot create IpSec tunnels");
+
+        // OP_MANAGE_IPSEC_TUNNELS will return MODE_ERRORED by default, including for the system
+        // server. If the appop is not granted, require that the caller has the MANAGE_IPSEC_TUNNELS
+        // permission or is the System Server.
+        if (AppOpsManager.MODE_ALLOWED == getAppOpsManager().noteOpNoThrow(
+                TUNNEL_OP, Binder.getCallingUid(), callingPackage)) {
+            return;
+        }
+        mContext.enforceCallingOrSelfPermission(
+                android.Manifest.permission.MANAGE_IPSEC_TUNNELS, "IpSecService");
+    }
+
+    private void createOrUpdateTransform(
+            IpSecConfig c, int resourceId, SpiRecord spiRecord, EncapSocketRecord socketRecord)
+            throws RemoteException {
+
+        int encapType = c.getEncapType(), encapLocalPort = 0, encapRemotePort = 0;
+        if (encapType != IpSecTransform.ENCAP_NONE) {
+            encapLocalPort = socketRecord.getPort();
+            encapRemotePort = c.getEncapRemotePort();
+        }
+
+        IpSecAlgorithm auth = c.getAuthentication();
+        IpSecAlgorithm crypt = c.getEncryption();
+        IpSecAlgorithm authCrypt = c.getAuthenticatedEncryption();
+
+        String cryptName;
+        if (crypt == null) {
+            cryptName = (authCrypt == null) ? IpSecAlgorithm.CRYPT_NULL : "";
+        } else {
+            cryptName = crypt.getName();
+        }
+
+        mNetd.ipSecAddSecurityAssociation(
+                Binder.getCallingUid(),
+                c.getMode(),
+                c.getSourceAddress(),
+                c.getDestinationAddress(),
+                (c.getNetwork() != null) ? c.getNetwork().getNetId() : 0,
+                spiRecord.getSpi(),
+                c.getMarkValue(),
+                c.getMarkMask(),
+                (auth != null) ? auth.getName() : "",
+                (auth != null) ? auth.getKey() : new byte[] {},
+                (auth != null) ? auth.getTruncationLengthBits() : 0,
+                cryptName,
+                (crypt != null) ? crypt.getKey() : new byte[] {},
+                (crypt != null) ? crypt.getTruncationLengthBits() : 0,
+                (authCrypt != null) ? authCrypt.getName() : "",
+                (authCrypt != null) ? authCrypt.getKey() : new byte[] {},
+                (authCrypt != null) ? authCrypt.getTruncationLengthBits() : 0,
+                encapType,
+                encapLocalPort,
+                encapRemotePort,
+                c.getXfrmInterfaceId());
+    }
+
+    /**
+     * Create a IPsec transform, which represents a single security association in the kernel. The
+     * transform will be cached by the system server and must be freed when no longer needed. It is
+     * possible to free one, deleting the SA from underneath sockets that are using it, which will
+     * result in all of those sockets becoming unable to send or receive data.
+     */
+    @Override
+    public synchronized IpSecTransformResponse createTransform(
+            IpSecConfig c, IBinder binder, String callingPackage) throws RemoteException {
+        Objects.requireNonNull(c);
+        if (c.getMode() == IpSecTransform.MODE_TUNNEL) {
+            enforceTunnelFeatureAndPermissions(callingPackage);
+        }
+        checkIpSecConfig(c);
+        Objects.requireNonNull(binder, "Null Binder passed to createTransform");
+        final int resourceId = mNextResourceId++;
+
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        List<RefcountedResource> dependencies = new ArrayList<>();
+
+        if (!userRecord.mTransformQuotaTracker.isAvailable()) {
+            return new IpSecTransformResponse(IpSecManager.Status.RESOURCE_UNAVAILABLE);
+        }
+
+        EncapSocketRecord socketRecord = null;
+        if (c.getEncapType() != IpSecTransform.ENCAP_NONE) {
+            RefcountedResource<EncapSocketRecord> refcountedSocketRecord =
+                    userRecord.mEncapSocketRecords.getRefcountedResourceOrThrow(
+                            c.getEncapSocketResourceId());
+            dependencies.add(refcountedSocketRecord);
+            socketRecord = refcountedSocketRecord.getResource();
+        }
+
+        RefcountedResource<SpiRecord> refcountedSpiRecord =
+                userRecord.mSpiRecords.getRefcountedResourceOrThrow(c.getSpiResourceId());
+        dependencies.add(refcountedSpiRecord);
+        SpiRecord spiRecord = refcountedSpiRecord.getResource();
+
+        createOrUpdateTransform(c, resourceId, spiRecord, socketRecord);
+
+        // SA was created successfully, time to construct a record and lock it away
+        userRecord.mTransformRecords.put(
+                resourceId,
+                new RefcountedResource<TransformRecord>(
+                        new TransformRecord(resourceId, c, spiRecord, socketRecord),
+                        binder,
+                        dependencies.toArray(new RefcountedResource[dependencies.size()])));
+        return new IpSecTransformResponse(IpSecManager.Status.OK, resourceId);
+    }
+
+    /**
+     * Delete a transport mode transform that was previously allocated by + registered with the
+     * system server. If this is called on an inactive (or non-existent) transform, it will not
+     * return an error. It's safe to de-allocate transforms that may have already been deleted for
+     * other reasons.
+     */
+    @Override
+    public synchronized void deleteTransform(int resourceId) throws RemoteException {
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        releaseResource(userRecord.mTransformRecords, resourceId);
+    }
+
+    /**
+     * Apply an active transport mode transform to a socket, which will apply the IPsec security
+     * association as a correspondent policy to the provided socket
+     */
+    @Override
+    public synchronized void applyTransportModeTransform(
+            ParcelFileDescriptor socket, int direction, int resourceId) throws RemoteException {
+        int callingUid = Binder.getCallingUid();
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(callingUid);
+        checkDirection(direction);
+        // Get transform record; if no transform is found, will throw IllegalArgumentException
+        TransformRecord info = userRecord.mTransformRecords.getResourceOrThrow(resourceId);
+
+        // TODO: make this a function.
+        if (info.mPid != getCallingPid() || info.mUid != callingUid) {
+            throw new SecurityException("Only the owner of an IpSec Transform may apply it!");
+        }
+
+        // Get config and check that to-be-applied transform has the correct mode
+        IpSecConfig c = info.getConfig();
+        Preconditions.checkArgument(
+                c.getMode() == IpSecTransform.MODE_TRANSPORT,
+                "Transform mode was not Transport mode; cannot be applied to a socket");
+
+        mNetd.ipSecApplyTransportModeTransform(
+                socket,
+                callingUid,
+                direction,
+                c.getSourceAddress(),
+                c.getDestinationAddress(),
+                info.getSpiRecord().getSpi());
+    }
+
+    /**
+     * Remove transport mode transforms from a socket, applying the default (empty) policy. This
+     * ensures that NO IPsec policy is applied to the socket (would be the equivalent of applying a
+     * policy that performs no IPsec). Today the resourceId parameter is passed but not used:
+     * reserved for future improved input validation.
+     */
+    @Override
+    public synchronized void removeTransportModeTransforms(ParcelFileDescriptor socket)
+            throws RemoteException {
+        mNetd.ipSecRemoveTransportModeTransform(socket);
+    }
+
+    /**
+     * Apply an active tunnel mode transform to a TunnelInterface, which will apply the IPsec
+     * security association as a correspondent policy to the provided interface
+     */
+    @Override
+    public synchronized void applyTunnelModeTransform(
+            int tunnelResourceId, int direction,
+            int transformResourceId, String callingPackage) throws RemoteException {
+        enforceTunnelFeatureAndPermissions(callingPackage);
+        checkDirection(direction);
+
+        int callingUid = Binder.getCallingUid();
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(callingUid);
+
+        // Get transform record; if no transform is found, will throw IllegalArgumentException
+        TransformRecord transformInfo =
+                userRecord.mTransformRecords.getResourceOrThrow(transformResourceId);
+
+        // Get tunnelInterface record; if no such interface is found, will throw
+        // IllegalArgumentException
+        TunnelInterfaceRecord tunnelInterfaceInfo =
+                userRecord.mTunnelInterfaceRecords.getResourceOrThrow(tunnelResourceId);
+
+        // Get config and check that to-be-applied transform has the correct mode
+        IpSecConfig c = transformInfo.getConfig();
+        Preconditions.checkArgument(
+                c.getMode() == IpSecTransform.MODE_TUNNEL,
+                "Transform mode was not Tunnel mode; cannot be applied to a tunnel interface");
+
+        EncapSocketRecord socketRecord = null;
+        if (c.getEncapType() != IpSecTransform.ENCAP_NONE) {
+            socketRecord =
+                    userRecord.mEncapSocketRecords.getResourceOrThrow(c.getEncapSocketResourceId());
+        }
+        SpiRecord spiRecord = transformInfo.getSpiRecord();
+
+        int mark =
+                (direction == IpSecManager.DIRECTION_OUT)
+                        ? tunnelInterfaceInfo.getOkey()
+                        : tunnelInterfaceInfo.getIkey(); // Ikey also used for FWD policies
+
+        try {
+            // Default to using the invalid SPI of 0 for inbound SAs. This allows policies to skip
+            // SPI matching as part of the template resolution.
+            int spi = IpSecManager.INVALID_SECURITY_PARAMETER_INDEX;
+            c.setXfrmInterfaceId(tunnelInterfaceInfo.getIfId());
+
+            // TODO: enable this when UPDSA supports updating marks. Adding kernel support upstream
+            //     (and backporting) would allow us to narrow the mark space, and ensure that the SA
+            //     and SPs have matching marks (as VTI are meant to be built).
+            // Currently update does nothing with marks. Leave empty (defaulting to 0) to ensure the
+            //     config matches the actual allocated resources in the kernel.
+            // All SAs will have zero marks (from creation time), and any policy that matches the
+            //     same src/dst could match these SAs. Non-IpSecService governed processes that
+            //     establish floating policies with the same src/dst may result in undefined
+            //     behavior. This is generally limited to vendor code due to the permissions
+            //     (CAP_NET_ADMIN) required.
+            //
+            // c.setMarkValue(mark);
+            // c.setMarkMask(0xffffffff);
+
+            if (direction == IpSecManager.DIRECTION_OUT) {
+                // Set output mark via underlying network (output only)
+                c.setNetwork(tunnelInterfaceInfo.getUnderlyingNetwork());
+
+                // Set outbound SPI only. We want inbound to use any valid SA (old, new) on rekeys,
+                // but want to guarantee outbound packets are sent over the new SA.
+                spi = spiRecord.getSpi();
+            }
+
+            // Always update the policy with the relevant XFRM_IF_ID
+            for (int selAddrFamily : ADDRESS_FAMILIES) {
+                mNetd.ipSecUpdateSecurityPolicy(
+                        callingUid,
+                        selAddrFamily,
+                        direction,
+                        transformInfo.getConfig().getSourceAddress(),
+                        transformInfo.getConfig().getDestinationAddress(),
+                        spi, // If outbound, also add SPI to the policy.
+                        mark, // Must always set policy mark; ikey/okey for VTIs
+                        0xffffffff,
+                        c.getXfrmInterfaceId());
+            }
+
+            // Update SA with tunnel mark (ikey or okey based on direction)
+            createOrUpdateTransform(c, transformResourceId, spiRecord, socketRecord);
+        } catch (ServiceSpecificException e) {
+            if (e.errorCode == EINVAL) {
+                throw new IllegalArgumentException(e.toString());
+            } else {
+                throw e;
+            }
+        }
+    }
+
+    @Override
+    protected synchronized void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+        mContext.enforceCallingOrSelfPermission(DUMP, TAG);
+
+        pw.println("IpSecService dump:");
+        pw.println();
+
+        pw.println("mUserResourceTracker:");
+        pw.println(mUserResourceTracker);
+    }
+}
diff --git a/service-t/src/com/android/server/NativeDaemonConnector.java b/service-t/src/com/android/server/NativeDaemonConnector.java
new file mode 100644
index 0000000..ec8d779
--- /dev/null
+++ b/service-t/src/com/android/server/NativeDaemonConnector.java
@@ -0,0 +1,704 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import android.net.LocalSocket;
+import android.net.LocalSocketAddress;
+import android.os.Build;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Looper;
+import android.os.Message;
+import android.os.PowerManager;
+import android.os.SystemClock;
+import android.util.LocalLog;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.Objects;
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Generic connector class for interfacing with a native daemon which uses the
+ * {@code libsysutils} FrameworkListener protocol.
+ */
+final class NativeDaemonConnector implements Runnable, Handler.Callback {
+    private final static boolean VDBG = false;
+
+    private final String TAG;
+
+    private String mSocket;
+    private OutputStream mOutputStream;
+    private LocalLog mLocalLog;
+
+    private volatile boolean mDebug = false;
+    private volatile Object mWarnIfHeld;
+
+    private final ResponseQueue mResponseQueue;
+
+    private final PowerManager.WakeLock mWakeLock;
+
+    private final Looper mLooper;
+
+    private INativeDaemonConnectorCallbacks mCallbacks;
+    private Handler mCallbackHandler;
+
+    private AtomicInteger mSequenceNumber;
+
+    private static final long DEFAULT_TIMEOUT = 1 * 60 * 1000; /* 1 minute */
+    private static final long WARN_EXECUTE_DELAY_MS = 500; /* .5 sec */
+
+    /** Lock held whenever communicating with native daemon. */
+    private final Object mDaemonLock = new Object();
+
+    private final int BUFFER_SIZE = 4096;
+
+    NativeDaemonConnector(INativeDaemonConnectorCallbacks callbacks, String socket,
+            int responseQueueSize, String logTag, int maxLogSize, PowerManager.WakeLock wl) {
+        mCallbacks = callbacks;
+        mSocket = socket;
+        mResponseQueue = new ResponseQueue(responseQueueSize);
+        mWakeLock = wl;
+        if (mWakeLock != null) {
+            mWakeLock.setReferenceCounted(true);
+        }
+        mSequenceNumber = new AtomicInteger(0);
+        TAG = logTag != null ? logTag : "NativeDaemonConnector";
+        mLocalLog = new LocalLog(maxLogSize);
+        final HandlerThread thread = new HandlerThread(TAG);
+        thread.start();
+        mLooper = thread.getLooper();
+    }
+
+    /**
+     * Enable Set debugging mode, which causes messages to also be written to both
+     * {@link Log} in addition to internal log.
+     */
+    public void setDebug(boolean debug) {
+        mDebug = debug;
+    }
+
+    /**
+     * Like SystemClock.uptimeMillis, except truncated to an int so it will fit in a message arg.
+     * Inaccurate across 49.7 days of uptime, but only used for debugging.
+     */
+    private int uptimeMillisInt() {
+        return (int) SystemClock.uptimeMillis() & Integer.MAX_VALUE;
+    }
+
+    /**
+     * Yell loudly if someone tries making future {@link #execute(Command)}
+     * calls while holding a lock on the given object.
+     */
+    public void setWarnIfHeld(Object warnIfHeld) {
+        if (mWarnIfHeld != null) {
+            throw new IllegalStateException("warnIfHeld is already set.");
+        }
+        mWarnIfHeld = Objects.requireNonNull(warnIfHeld);
+    }
+
+    @Override
+    public void run() {
+        mCallbackHandler = new Handler(mLooper, this);
+
+        while (true) {
+            try {
+                listenToSocket();
+            } catch (Exception e) {
+                loge("Error in NativeDaemonConnector: " + e);
+                SystemClock.sleep(5000);
+            }
+        }
+    }
+
+    @Override
+    public boolean handleMessage(Message msg) {
+        final String event = (String) msg.obj;
+        final int start = uptimeMillisInt();
+        final int sent = msg.arg1;
+        try {
+            if (!mCallbacks.onEvent(msg.what, event, NativeDaemonEvent.unescapeArgs(event))) {
+                log(String.format("Unhandled event '%s'", event));
+            }
+        } catch (Exception e) {
+            loge("Error handling '" + event + "': " + e);
+        } finally {
+            if (mCallbacks.onCheckHoldWakeLock(msg.what) && mWakeLock != null) {
+                mWakeLock.release();
+            }
+            final int end = uptimeMillisInt();
+            if (start > sent && start - sent > WARN_EXECUTE_DELAY_MS) {
+                loge(String.format("NDC event {%s} processed too late: %dms", event, start - sent));
+            }
+            if (end > start && end - start > WARN_EXECUTE_DELAY_MS) {
+                loge(String.format("NDC event {%s} took too long: %dms", event, end - start));
+            }
+        }
+        return true;
+    }
+
+    private LocalSocketAddress determineSocketAddress() {
+        // If we're testing, set up a socket in a namespace that's accessible to test code.
+        // In order to ensure that unprivileged apps aren't able to impersonate native daemons on
+        // production devices, even if said native daemons ill-advisedly pick a socket name that
+        // starts with __test__, only allow this on debug builds.
+        if (mSocket.startsWith("__test__") && Build.isDebuggable()) {
+            return new LocalSocketAddress(mSocket);
+        } else {
+            return new LocalSocketAddress(mSocket, LocalSocketAddress.Namespace.RESERVED);
+        }
+    }
+
+    private void listenToSocket() throws IOException {
+        LocalSocket socket = null;
+
+        try {
+            socket = new LocalSocket();
+            LocalSocketAddress address = determineSocketAddress();
+
+            socket.connect(address);
+
+            InputStream inputStream = socket.getInputStream();
+            synchronized (mDaemonLock) {
+                mOutputStream = socket.getOutputStream();
+            }
+
+            mCallbacks.onDaemonConnected();
+
+            FileDescriptor[] fdList = null;
+            byte[] buffer = new byte[BUFFER_SIZE];
+            int start = 0;
+
+            while (true) {
+                int count = inputStream.read(buffer, start, BUFFER_SIZE - start);
+                if (count < 0) {
+                    loge("got " + count + " reading with start = " + start);
+                    break;
+                }
+                fdList = socket.getAncillaryFileDescriptors();
+
+                // Add our starting point to the count and reset the start.
+                count += start;
+                start = 0;
+
+                for (int i = 0; i < count; i++) {
+                    if (buffer[i] == 0) {
+                        // Note - do not log this raw message since it may contain
+                        // sensitive data
+                        final String rawEvent = new String(
+                                buffer, start, i - start, StandardCharsets.UTF_8);
+
+                        boolean releaseWl = false;
+                        try {
+                            final NativeDaemonEvent event =
+                                    NativeDaemonEvent.parseRawEvent(rawEvent, fdList);
+
+                            log("RCV <- {" + event + "}");
+
+                            if (event.isClassUnsolicited()) {
+                                // TODO: migrate to sending NativeDaemonEvent instances
+                                if (mCallbacks.onCheckHoldWakeLock(event.getCode())
+                                        && mWakeLock != null) {
+                                    mWakeLock.acquire();
+                                    releaseWl = true;
+                                }
+                                Message msg = mCallbackHandler.obtainMessage(
+                                        event.getCode(), uptimeMillisInt(), 0, event.getRawEvent());
+                                if (mCallbackHandler.sendMessage(msg)) {
+                                    releaseWl = false;
+                                }
+                            } else {
+                                mResponseQueue.add(event.getCmdNumber(), event);
+                            }
+                        } catch (IllegalArgumentException e) {
+                            log("Problem parsing message " + e);
+                        } finally {
+                            if (releaseWl) {
+                                mWakeLock.release();
+                            }
+                        }
+
+                        start = i + 1;
+                    }
+                }
+
+                if (start == 0) {
+                    log("RCV incomplete");
+                }
+
+                // We should end at the amount we read. If not, compact then
+                // buffer and read again.
+                if (start != count) {
+                    final int remaining = BUFFER_SIZE - start;
+                    System.arraycopy(buffer, start, buffer, 0, remaining);
+                    start = remaining;
+                } else {
+                    start = 0;
+                }
+            }
+        } catch (IOException ex) {
+            loge("Communications error: " + ex);
+            throw ex;
+        } finally {
+            synchronized (mDaemonLock) {
+                if (mOutputStream != null) {
+                    try {
+                        loge("closing stream for " + mSocket);
+                        mOutputStream.close();
+                    } catch (IOException e) {
+                        loge("Failed closing output stream: " + e);
+                    }
+                    mOutputStream = null;
+                }
+            }
+
+            try {
+                if (socket != null) {
+                    socket.close();
+                }
+            } catch (IOException ex) {
+                loge("Failed closing socket: " + ex);
+            }
+        }
+    }
+
+    /**
+     * Wrapper around argument that indicates it's sensitive and shouldn't be
+     * logged.
+     */
+    public static class SensitiveArg {
+        private final Object mArg;
+
+        public SensitiveArg(Object arg) {
+            mArg = arg;
+        }
+
+        @Override
+        public String toString() {
+            return String.valueOf(mArg);
+        }
+    }
+
+    /**
+     * Make command for daemon, escaping arguments as needed.
+     */
+    @VisibleForTesting
+    static void makeCommand(StringBuilder rawBuilder, StringBuilder logBuilder, int sequenceNumber,
+            String cmd, Object... args) {
+        if (cmd.indexOf('\0') >= 0) {
+            throw new IllegalArgumentException("Unexpected command: " + cmd);
+        }
+        if (cmd.indexOf(' ') >= 0) {
+            throw new IllegalArgumentException("Arguments must be separate from command");
+        }
+
+        rawBuilder.append(sequenceNumber).append(' ').append(cmd);
+        logBuilder.append(sequenceNumber).append(' ').append(cmd);
+        for (Object arg : args) {
+            final String argString = String.valueOf(arg);
+            if (argString.indexOf('\0') >= 0) {
+                throw new IllegalArgumentException("Unexpected argument: " + arg);
+            }
+
+            rawBuilder.append(' ');
+            logBuilder.append(' ');
+
+            appendEscaped(rawBuilder, argString);
+            if (arg instanceof SensitiveArg) {
+                logBuilder.append("[scrubbed]");
+            } else {
+                appendEscaped(logBuilder, argString);
+            }
+        }
+
+        rawBuilder.append('\0');
+    }
+
+    /**
+     * Method that waits until all asychronous notifications sent by the native daemon have
+     * been processed. This method must not be called on the notification thread or an
+     * exception will be thrown.
+     */
+    public void waitForCallbacks() {
+        if (Thread.currentThread() == mLooper.getThread()) {
+            throw new IllegalStateException("Must not call this method on callback thread");
+        }
+
+        final CountDownLatch latch = new CountDownLatch(1);
+        mCallbackHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                latch.countDown();
+            }
+        });
+        try {
+            latch.await();
+        } catch (InterruptedException e) {
+            Log.wtf(TAG, "Interrupted while waiting for unsolicited response handling", e);
+        }
+    }
+
+    /**
+     * Issue the given command to the native daemon and return a single expected
+     * response.
+     *
+     * @throws NativeDaemonConnectorException when problem communicating with
+     *             native daemon, or if the response matches
+     *             {@link NativeDaemonEvent#isClassClientError()} or
+     *             {@link NativeDaemonEvent#isClassServerError()}.
+     */
+    public NativeDaemonEvent execute(Command cmd) throws NativeDaemonConnectorException {
+        return execute(cmd.mCmd, cmd.mArguments.toArray());
+    }
+
+    /**
+     * Issue the given command to the native daemon and return a single expected
+     * response. Any arguments must be separated from base command so they can
+     * be properly escaped.
+     *
+     * @throws NativeDaemonConnectorException when problem communicating with
+     *             native daemon, or if the response matches
+     *             {@link NativeDaemonEvent#isClassClientError()} or
+     *             {@link NativeDaemonEvent#isClassServerError()}.
+     */
+    public NativeDaemonEvent execute(String cmd, Object... args)
+            throws NativeDaemonConnectorException {
+        return execute(DEFAULT_TIMEOUT, cmd, args);
+    }
+
+    public NativeDaemonEvent execute(long timeoutMs, String cmd, Object... args)
+            throws NativeDaemonConnectorException {
+        final NativeDaemonEvent[] events = executeForList(timeoutMs, cmd, args);
+        if (events.length != 1) {
+            throw new NativeDaemonConnectorException(
+                    "Expected exactly one response, but received " + events.length);
+        }
+        return events[0];
+    }
+
+    /**
+     * Issue the given command to the native daemon and return any
+     * {@link NativeDaemonEvent#isClassContinue()} responses, including the
+     * final terminal response.
+     *
+     * @throws NativeDaemonConnectorException when problem communicating with
+     *             native daemon, or if the response matches
+     *             {@link NativeDaemonEvent#isClassClientError()} or
+     *             {@link NativeDaemonEvent#isClassServerError()}.
+     */
+    public NativeDaemonEvent[] executeForList(Command cmd) throws NativeDaemonConnectorException {
+        return executeForList(cmd.mCmd, cmd.mArguments.toArray());
+    }
+
+    /**
+     * Issue the given command to the native daemon and return any
+     * {@link NativeDaemonEvent#isClassContinue()} responses, including the
+     * final terminal response. Any arguments must be separated from base
+     * command so they can be properly escaped.
+     *
+     * @throws NativeDaemonConnectorException when problem communicating with
+     *             native daemon, or if the response matches
+     *             {@link NativeDaemonEvent#isClassClientError()} or
+     *             {@link NativeDaemonEvent#isClassServerError()}.
+     */
+    public NativeDaemonEvent[] executeForList(String cmd, Object... args)
+            throws NativeDaemonConnectorException {
+        return executeForList(DEFAULT_TIMEOUT, cmd, args);
+    }
+
+    /**
+     * Issue the given command to the native daemon and return any {@linke
+     * NativeDaemonEvent@isClassContinue()} responses, including the final
+     * terminal response. Note that the timeout does not count time in deep
+     * sleep. Any arguments must be separated from base command so they can be
+     * properly escaped.
+     *
+     * @throws NativeDaemonConnectorException when problem communicating with
+     *             native daemon, or if the response matches
+     *             {@link NativeDaemonEvent#isClassClientError()} or
+     *             {@link NativeDaemonEvent#isClassServerError()}.
+     */
+    public NativeDaemonEvent[] executeForList(long timeoutMs, String cmd, Object... args)
+            throws NativeDaemonConnectorException {
+        if (mWarnIfHeld != null && Thread.holdsLock(mWarnIfHeld)) {
+            Log.wtf(TAG, "Calling thread " + Thread.currentThread().getName() + " is holding 0x"
+                    + Integer.toHexString(System.identityHashCode(mWarnIfHeld)), new Throwable());
+        }
+
+        final long startTime = SystemClock.elapsedRealtime();
+
+        final ArrayList<NativeDaemonEvent> events = new ArrayList<>();
+
+        final StringBuilder rawBuilder = new StringBuilder();
+        final StringBuilder logBuilder = new StringBuilder();
+        final int sequenceNumber = mSequenceNumber.incrementAndGet();
+
+        makeCommand(rawBuilder, logBuilder, sequenceNumber, cmd, args);
+
+        final String rawCmd = rawBuilder.toString();
+        final String logCmd = logBuilder.toString();
+
+        log("SND -> {" + logCmd + "}");
+
+        synchronized (mDaemonLock) {
+            if (mOutputStream == null) {
+                throw new NativeDaemonConnectorException("missing output stream");
+            } else {
+                try {
+                    mOutputStream.write(rawCmd.getBytes(StandardCharsets.UTF_8));
+                } catch (IOException e) {
+                    throw new NativeDaemonConnectorException("problem sending command", e);
+                }
+            }
+        }
+
+        NativeDaemonEvent event = null;
+        do {
+            event = mResponseQueue.remove(sequenceNumber, timeoutMs, logCmd);
+            if (event == null) {
+                loge("timed-out waiting for response to " + logCmd);
+                throw new NativeDaemonTimeoutException(logCmd, event);
+            }
+            if (VDBG) log("RMV <- {" + event + "}");
+            events.add(event);
+        } while (event.isClassContinue());
+
+        final long endTime = SystemClock.elapsedRealtime();
+        if (endTime - startTime > WARN_EXECUTE_DELAY_MS) {
+            loge("NDC Command {" + logCmd + "} took too long (" + (endTime - startTime) + "ms)");
+        }
+
+        if (event.isClassClientError()) {
+            throw new NativeDaemonArgumentException(logCmd, event);
+        }
+        if (event.isClassServerError()) {
+            throw new NativeDaemonFailureException(logCmd, event);
+        }
+
+        return events.toArray(new NativeDaemonEvent[events.size()]);
+    }
+
+    /**
+     * Append the given argument to {@link StringBuilder}, escaping as needed,
+     * and surrounding with quotes when it contains spaces.
+     */
+    @VisibleForTesting
+    static void appendEscaped(StringBuilder builder, String arg) {
+        final boolean hasSpaces = arg.indexOf(' ') >= 0;
+        if (hasSpaces) {
+            builder.append('"');
+        }
+
+        final int length = arg.length();
+        for (int i = 0; i < length; i++) {
+            final char c = arg.charAt(i);
+
+            if (c == '"') {
+                builder.append("\\\"");
+            } else if (c == '\\') {
+                builder.append("\\\\");
+            } else {
+                builder.append(c);
+            }
+        }
+
+        if (hasSpaces) {
+            builder.append('"');
+        }
+    }
+
+    private static class NativeDaemonArgumentException extends NativeDaemonConnectorException {
+        public NativeDaemonArgumentException(String command, NativeDaemonEvent event) {
+            super(command, event);
+        }
+
+        @Override
+        public IllegalArgumentException rethrowAsParcelableException() {
+            throw new IllegalArgumentException(getMessage(), this);
+        }
+    }
+
+    private static class NativeDaemonFailureException extends NativeDaemonConnectorException {
+        public NativeDaemonFailureException(String command, NativeDaemonEvent event) {
+            super(command, event);
+        }
+    }
+
+    /**
+     * Command builder that handles argument list building. Any arguments must
+     * be separated from base command so they can be properly escaped.
+     */
+    public static class Command {
+        private String mCmd;
+        private ArrayList<Object> mArguments = new ArrayList<>();
+
+        public Command(String cmd, Object... args) {
+            mCmd = cmd;
+            for (Object arg : args) {
+                appendArg(arg);
+            }
+        }
+
+        public Command appendArg(Object arg) {
+            mArguments.add(arg);
+            return this;
+        }
+    }
+
+    public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+        mLocalLog.dump(fd, pw, args);
+        pw.println();
+        mResponseQueue.dump(fd, pw, args);
+    }
+
+    private void log(String logstring) {
+        if (mDebug) Log.d(TAG, logstring);
+        mLocalLog.log(logstring);
+    }
+
+    private void loge(String logstring) {
+        Log.e(TAG, logstring);
+        mLocalLog.log(logstring);
+    }
+
+    private static class ResponseQueue {
+
+        private static class PendingCmd {
+            public final int cmdNum;
+            public final String logCmd;
+
+            public BlockingQueue<NativeDaemonEvent> responses =
+                    new ArrayBlockingQueue<NativeDaemonEvent>(10);
+
+            // The availableResponseCount member is used to track when we can remove this
+            // instance from the ResponseQueue.
+            // This is used under the protection of a sync of the mPendingCmds object.
+            // A positive value means we've had more writers retreive this object while
+            // a negative value means we've had more readers.  When we've had an equal number
+            // (it goes to zero) we can remove this object from the mPendingCmds list.
+            // Note that we may have more responses for this command (and more readers
+            // coming), but that would result in a new PendingCmd instance being created
+            // and added with the same cmdNum.
+            // Also note that when this goes to zero it just means a parity of readers and
+            // writers have retrieved this object - not that they are done using it.  The
+            // responses queue may well have more responses yet to be read or may get more
+            // responses added to it.  But all those readers/writers have retreived and
+            // hold references to this instance already so it can be removed from
+            // mPendingCmds queue.
+            public int availableResponseCount;
+
+            public PendingCmd(int cmdNum, String logCmd) {
+                this.cmdNum = cmdNum;
+                this.logCmd = logCmd;
+            }
+        }
+
+        private final LinkedList<PendingCmd> mPendingCmds;
+        private int mMaxCount;
+
+        ResponseQueue(int maxCount) {
+            mPendingCmds = new LinkedList<PendingCmd>();
+            mMaxCount = maxCount;
+        }
+
+        public void add(int cmdNum, NativeDaemonEvent response) {
+            PendingCmd found = null;
+            synchronized (mPendingCmds) {
+                for (PendingCmd pendingCmd : mPendingCmds) {
+                    if (pendingCmd.cmdNum == cmdNum) {
+                        found = pendingCmd;
+                        break;
+                    }
+                }
+                if (found == null) {
+                    // didn't find it - make sure our queue isn't too big before adding
+                    while (mPendingCmds.size() >= mMaxCount) {
+                        Log.e("NativeDaemonConnector.ResponseQueue",
+                                "more buffered than allowed: " + mPendingCmds.size() +
+                                " >= " + mMaxCount);
+                        // let any waiter timeout waiting for this
+                        PendingCmd pendingCmd = mPendingCmds.remove();
+                        Log.e("NativeDaemonConnector.ResponseQueue",
+                                "Removing request: " + pendingCmd.logCmd + " (" +
+                                pendingCmd.cmdNum + ")");
+                    }
+                    found = new PendingCmd(cmdNum, null);
+                    mPendingCmds.add(found);
+                }
+                found.availableResponseCount++;
+                // if a matching remove call has already retrieved this we can remove this
+                // instance from our list
+                if (found.availableResponseCount == 0) mPendingCmds.remove(found);
+            }
+            try {
+                found.responses.put(response);
+            } catch (InterruptedException e) { }
+        }
+
+        // note that the timeout does not count time in deep sleep.  If you don't want
+        // the device to sleep, hold a wakelock
+        public NativeDaemonEvent remove(int cmdNum, long timeoutMs, String logCmd) {
+            PendingCmd found = null;
+            synchronized (mPendingCmds) {
+                for (PendingCmd pendingCmd : mPendingCmds) {
+                    if (pendingCmd.cmdNum == cmdNum) {
+                        found = pendingCmd;
+                        break;
+                    }
+                }
+                if (found == null) {
+                    found = new PendingCmd(cmdNum, logCmd);
+                    mPendingCmds.add(found);
+                }
+                found.availableResponseCount--;
+                // if a matching add call has already retrieved this we can remove this
+                // instance from our list
+                if (found.availableResponseCount == 0) mPendingCmds.remove(found);
+            }
+            NativeDaemonEvent result = null;
+            try {
+                result = found.responses.poll(timeoutMs, TimeUnit.MILLISECONDS);
+            } catch (InterruptedException e) {}
+            if (result == null) {
+                Log.e("NativeDaemonConnector.ResponseQueue", "Timeout waiting for response");
+            }
+            return result;
+        }
+
+        public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+            pw.println("Pending requests:");
+            synchronized (mPendingCmds) {
+                for (PendingCmd pendingCmd : mPendingCmds) {
+                    pw.println("  Cmd " + pendingCmd.cmdNum + " - " + pendingCmd.logCmd);
+                }
+            }
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/NativeDaemonConnectorException.java b/service-t/src/com/android/server/NativeDaemonConnectorException.java
new file mode 100644
index 0000000..4d8881c
--- /dev/null
+++ b/service-t/src/com/android/server/NativeDaemonConnectorException.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import android.os.Parcel;
+
+/**
+ * An exception that indicates there was an error with a
+ * {@link NativeDaemonConnector} operation.
+ */
+public class NativeDaemonConnectorException extends Exception {
+    private String mCmd;
+    private NativeDaemonEvent mEvent;
+
+    public NativeDaemonConnectorException(String detailMessage) {
+        super(detailMessage);
+    }
+
+    public NativeDaemonConnectorException(String detailMessage, Throwable throwable) {
+        super(detailMessage, throwable);
+    }
+
+    public NativeDaemonConnectorException(String cmd, NativeDaemonEvent event) {
+        super("command '" + cmd + "' failed with '" + event + "'");
+        mCmd = cmd;
+        mEvent = event;
+    }
+
+    public int getCode() {
+        return mEvent != null ? mEvent.getCode() : -1;
+    }
+
+    public String getCmd() {
+        return mCmd;
+    }
+
+    /**
+     * Rethrow as a {@link RuntimeException} subclass that is handled by
+     * {@link Parcel#writeException(Exception)}.
+     */
+    public IllegalArgumentException rethrowAsParcelableException() {
+        throw new IllegalStateException(getMessage(), this);
+    }
+}
diff --git a/service-t/src/com/android/server/NativeDaemonEvent.java b/service-t/src/com/android/server/NativeDaemonEvent.java
new file mode 100644
index 0000000..5683694
--- /dev/null
+++ b/service-t/src/com/android/server/NativeDaemonEvent.java
@@ -0,0 +1,267 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import android.util.Log;
+
+import java.io.FileDescriptor;
+import java.util.ArrayList;
+
+/**
+ * Parsed event from native side of {@link NativeDaemonConnector}.
+ */
+public class NativeDaemonEvent {
+
+    // TODO: keep class ranges in sync with ResponseCode.h
+    // TODO: swap client and server error ranges to roughly mirror HTTP spec
+
+    private final int mCmdNumber;
+    private final int mCode;
+    private final String mMessage;
+    private final String mRawEvent;
+    private final String mLogMessage;
+    private String[] mParsed;
+    private FileDescriptor[] mFdList;
+
+    private NativeDaemonEvent(int cmdNumber, int code, String message,
+                              String rawEvent, String logMessage, FileDescriptor[] fdList) {
+        mCmdNumber = cmdNumber;
+        mCode = code;
+        mMessage = message;
+        mRawEvent = rawEvent;
+        mLogMessage = logMessage;
+        mParsed = null;
+        mFdList = fdList;
+    }
+
+    static public final String SENSITIVE_MARKER = "{{sensitive}}";
+
+    public int getCmdNumber() {
+        return mCmdNumber;
+    }
+
+    public int getCode() {
+        return mCode;
+    }
+
+    public String getMessage() {
+        return mMessage;
+    }
+
+    public FileDescriptor[] getFileDescriptors() {
+        return mFdList;
+    }
+
+    @Deprecated
+    public String getRawEvent() {
+        return mRawEvent;
+    }
+
+    @Override
+    public String toString() {
+        return mLogMessage;
+    }
+
+    /**
+     * Test if event represents a partial response which is continued in
+     * additional subsequent events.
+     */
+    public boolean isClassContinue() {
+        return mCode >= 100 && mCode < 200;
+    }
+
+    /**
+     * Test if event represents a command success.
+     */
+    public boolean isClassOk() {
+        return mCode >= 200 && mCode < 300;
+    }
+
+    /**
+     * Test if event represents a remote native daemon error.
+     */
+    public boolean isClassServerError() {
+        return mCode >= 400 && mCode < 500;
+    }
+
+    /**
+     * Test if event represents a command syntax or argument error.
+     */
+    public boolean isClassClientError() {
+        return mCode >= 500 && mCode < 600;
+    }
+
+    /**
+     * Test if event represents an unsolicited event from native daemon.
+     */
+    public boolean isClassUnsolicited() {
+        return isClassUnsolicited(mCode);
+    }
+
+    private static boolean isClassUnsolicited(int code) {
+        return code >= 600 && code < 700;
+    }
+
+    /**
+     * Verify this event matches the given code.
+     *
+     * @throws IllegalStateException if {@link #getCode()} doesn't match.
+     */
+    public void checkCode(int code) {
+        if (mCode != code) {
+            throw new IllegalStateException("Expected " + code + " but was: " + this);
+        }
+    }
+
+    /**
+     * Parse the given raw event into {@link NativeDaemonEvent} instance.
+     *
+     * @throws IllegalArgumentException when line doesn't match format expected
+     *             from native side.
+     */
+    public static NativeDaemonEvent parseRawEvent(String rawEvent, FileDescriptor[] fdList) {
+        final String[] parsed = rawEvent.split(" ");
+        if (parsed.length < 2) {
+            throw new IllegalArgumentException("Insufficient arguments");
+        }
+
+        int skiplength = 0;
+
+        final int code;
+        try {
+            code = Integer.parseInt(parsed[0]);
+            skiplength = parsed[0].length() + 1;
+        } catch (NumberFormatException e) {
+            throw new IllegalArgumentException("problem parsing code", e);
+        }
+
+        int cmdNumber = -1;
+        if (isClassUnsolicited(code) == false) {
+            if (parsed.length < 3) {
+                throw new IllegalArgumentException("Insufficient arguemnts");
+            }
+            try {
+                cmdNumber = Integer.parseInt(parsed[1]);
+                skiplength += parsed[1].length() + 1;
+            } catch (NumberFormatException e) {
+                throw new IllegalArgumentException("problem parsing cmdNumber", e);
+            }
+        }
+
+        String logMessage = rawEvent;
+        if (parsed.length > 2 && parsed[2].equals(SENSITIVE_MARKER)) {
+            skiplength += parsed[2].length() + 1;
+            logMessage = parsed[0] + " " + parsed[1] + " {}";
+        }
+
+        final String message = rawEvent.substring(skiplength);
+
+        return new NativeDaemonEvent(cmdNumber, code, message, rawEvent, logMessage, fdList);
+    }
+
+    /**
+     * Filter the given {@link NativeDaemonEvent} list, returning
+     * {@link #getMessage()} for any events matching the requested code.
+     */
+    public static String[] filterMessageList(NativeDaemonEvent[] events, int matchCode) {
+        final ArrayList<String> result = new ArrayList<>();
+        for (NativeDaemonEvent event : events) {
+            if (event.getCode() == matchCode) {
+                result.add(event.getMessage());
+            }
+        }
+        return result.toArray(new String[result.size()]);
+    }
+
+    /**
+     * Find the Nth field of the event.
+     *
+     * This ignores and code or cmdNum, the first return value is given for N=0.
+     * Also understands "\"quoted\" multiword responses" and tries them as a single field
+     */
+    public String getField(int n) {
+        if (mParsed == null) {
+            mParsed = unescapeArgs(mRawEvent);
+        }
+        n += 2; // skip code and command#
+        if (n > mParsed.length) return null;
+            return mParsed[n];
+        }
+
+    public static String[] unescapeArgs(String rawEvent) {
+        final boolean DEBUG_ROUTINE = false;
+        final String LOGTAG = "unescapeArgs";
+        final ArrayList<String> parsed = new ArrayList<String>();
+        final int length = rawEvent.length();
+        int current = 0;
+        int wordEnd = -1;
+        boolean quoted = false;
+
+        if (DEBUG_ROUTINE) Log.e(LOGTAG, "parsing '" + rawEvent + "'");
+        if (rawEvent.charAt(current) == '\"') {
+            quoted = true;
+            current++;
+        }
+        while (current < length) {
+            // find the end of the word
+            char terminator = quoted ? '\"' : ' ';
+            wordEnd = current;
+            while (wordEnd < length && rawEvent.charAt(wordEnd) != terminator) {
+                if (rawEvent.charAt(wordEnd) == '\\') {
+                    // skip the escaped char
+                    ++wordEnd;
+                }
+                ++wordEnd;
+            }
+            if (wordEnd > length) wordEnd = length;
+            String word = rawEvent.substring(current, wordEnd);
+            current += word.length();
+            if (!quoted) {
+                word = word.trim();
+            } else {
+                current++;  // skip the trailing quote
+            }
+            // unescape stuff within the word
+            word = word.replace("\\\\", "\\");
+            word = word.replace("\\\"", "\"");
+
+            if (DEBUG_ROUTINE) Log.e(LOGTAG, "found '" + word + "'");
+            parsed.add(word);
+
+            // find the beginning of the next word - either of these options
+            int nextSpace = rawEvent.indexOf(' ', current);
+            int nextQuote = rawEvent.indexOf(" \"", current);
+            if (DEBUG_ROUTINE) {
+                Log.e(LOGTAG, "nextSpace=" + nextSpace + ", nextQuote=" + nextQuote);
+            }
+            if (nextQuote > -1 && nextQuote <= nextSpace) {
+                quoted = true;
+                current = nextQuote + 2;
+            } else {
+                quoted = false;
+                if (nextSpace > -1) {
+                    current = nextSpace + 1;
+                }
+            } // else we just start the next word after the current and read til the end
+            if (DEBUG_ROUTINE) {
+                Log.e(LOGTAG, "next loop - current=" + current
+                        + ", length=" + length + ", quoted=" + quoted);
+            }
+        }
+        return parsed.toArray(new String[parsed.size()]);
+    }
+}
diff --git a/service-t/src/com/android/server/NativeDaemonTimeoutException.java b/service-t/src/com/android/server/NativeDaemonTimeoutException.java
new file mode 100644
index 0000000..658f7d6
--- /dev/null
+++ b/service-t/src/com/android/server/NativeDaemonTimeoutException.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+/**
+ * An exception that indicates there was a timeout with a
+ * {@link NativeDaemonConnector} operation.
+ */
+public class NativeDaemonTimeoutException extends NativeDaemonConnectorException {
+    public NativeDaemonTimeoutException(String command, NativeDaemonEvent event) {
+        super(command, event);
+    }
+}
+
diff --git a/service-t/src/com/android/server/NsdService.java b/service-t/src/com/android/server/NsdService.java
new file mode 100644
index 0000000..ddf6d2c
--- /dev/null
+++ b/service-t/src/com/android/server/NsdService.java
@@ -0,0 +1,1146 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.net.ConnectivityManager;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.nsd.INsdManager;
+import android.net.nsd.INsdManagerCallback;
+import android.net.nsd.INsdServiceConnector;
+import android.net.nsd.NsdManager;
+import android.net.nsd.NsdServiceInfo;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.IBinder;
+import android.os.Message;
+import android.os.RemoteException;
+import android.os.UserHandle;
+import android.util.Base64;
+import android.util.Log;
+import android.util.Pair;
+import android.util.SparseArray;
+import android.util.SparseIntArray;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.State;
+import com.android.internal.util.StateMachine;
+import com.android.net.module.util.DnsSdTxtRecord;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.concurrent.CountDownLatch;
+
+/**
+ * Network Service Discovery Service handles remote service discovery operation requests by
+ * implementing the INsdManager interface.
+ *
+ * @hide
+ */
+public class NsdService extends INsdManager.Stub {
+    private static final String TAG = "NsdService";
+    private static final String MDNS_TAG = "mDnsConnector";
+
+    private static final boolean DBG = true;
+    private static final long CLEANUP_DELAY_MS = 10000;
+    private static final int IFACE_IDX_ANY = 0;
+
+    private final Context mContext;
+    private final NsdStateMachine mNsdStateMachine;
+    private final DaemonConnection mDaemon;
+    private final NativeCallbackReceiver mDaemonCallback;
+
+    /**
+     * Clients receiving asynchronous messages
+     */
+    private final HashMap<NsdServiceConnector, ClientInfo> mClients = new HashMap<>();
+
+    /* A map from unique id to client info */
+    private final SparseArray<ClientInfo> mIdToClientInfoMap= new SparseArray<>();
+
+    private final long mCleanupDelayMs;
+
+    private static final int INVALID_ID = 0;
+    private int mUniqueId = 1;
+    // The count of the connected legacy clients.
+    private int mLegacyClientCount = 0;
+
+    private class NsdStateMachine extends StateMachine {
+
+        private final DefaultState mDefaultState = new DefaultState();
+        private final DisabledState mDisabledState = new DisabledState();
+        private final EnabledState mEnabledState = new EnabledState();
+
+        @Override
+        protected String getWhatToString(int what) {
+            return NsdManager.nameOf(what);
+        }
+
+        private void maybeStartDaemon() {
+            mDaemon.maybeStart();
+            maybeScheduleStop();
+        }
+
+        private boolean isAnyRequestActive() {
+            return mIdToClientInfoMap.size() != 0;
+        }
+
+        private void scheduleStop() {
+            sendMessageDelayed(NsdManager.DAEMON_CLEANUP, mCleanupDelayMs);
+        }
+        private void maybeScheduleStop() {
+            // The native daemon should stay alive and can't be cleanup
+            // if any legacy client connected.
+            if (!isAnyRequestActive() && mLegacyClientCount == 0) {
+                scheduleStop();
+            }
+        }
+
+        private void cancelStop() {
+            this.removeMessages(NsdManager.DAEMON_CLEANUP);
+        }
+
+        NsdStateMachine(String name, Handler handler) {
+            super(name, handler);
+            addState(mDefaultState);
+                addState(mDisabledState, mDefaultState);
+                addState(mEnabledState, mDefaultState);
+            State initialState = mEnabledState;
+            setInitialState(initialState);
+            setLogRecSize(25);
+        }
+
+        class DefaultState extends State {
+            @Override
+            public boolean processMessage(Message msg) {
+                final ClientInfo cInfo;
+                final int clientId = msg.arg2;
+                switch (msg.what) {
+                    case NsdManager.REGISTER_CLIENT:
+                        final Pair<NsdServiceConnector, INsdManagerCallback> arg =
+                                (Pair<NsdServiceConnector, INsdManagerCallback>) msg.obj;
+                        final INsdManagerCallback cb = arg.second;
+                        try {
+                            cb.asBinder().linkToDeath(arg.first, 0);
+                            cInfo = new ClientInfo(cb);
+                            mClients.put(arg.first, cInfo);
+                        } catch (RemoteException e) {
+                            Log.w(TAG, "Client " + clientId + " has already died");
+                        }
+                        break;
+                    case NsdManager.UNREGISTER_CLIENT:
+                        final NsdServiceConnector connector = (NsdServiceConnector) msg.obj;
+                        cInfo = mClients.remove(connector);
+                        if (cInfo != null) {
+                            cInfo.expungeAllRequests();
+                            if (cInfo.isLegacy()) {
+                                mLegacyClientCount -= 1;
+                            }
+                        }
+                        maybeScheduleStop();
+                        break;
+                    case NsdManager.DISCOVER_SERVICES:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cInfo.onDiscoverServicesFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                       break;
+                    case NsdManager.STOP_DISCOVERY:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cInfo.onStopDiscoveryFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.REGISTER_SERVICE:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cInfo.onRegisterServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.UNREGISTER_SERVICE:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cInfo.onUnregisterServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.RESOLVE_SERVICE:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cInfo.onResolveServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.DAEMON_CLEANUP:
+                        mDaemon.maybeStop();
+                        break;
+                    // This event should be only sent by the legacy (target SDK < S) clients.
+                    // Mark the sending client as legacy.
+                    case NsdManager.DAEMON_STARTUP:
+                        cInfo = getClientInfoForReply(msg);
+                        if (cInfo != null) {
+                            cancelStop();
+                            cInfo.setLegacy();
+                            mLegacyClientCount += 1;
+                            maybeStartDaemon();
+                        }
+                        break;
+                    case NsdManager.NATIVE_DAEMON_EVENT:
+                    default:
+                        Log.e(TAG, "Unhandled " + msg);
+                        return NOT_HANDLED;
+                }
+                return HANDLED;
+            }
+
+            private ClientInfo getClientInfoForReply(Message msg) {
+                final ListenerArgs args = (ListenerArgs) msg.obj;
+                return mClients.get(args.connector);
+            }
+        }
+
+        class DisabledState extends State {
+            @Override
+            public void enter() {
+                sendNsdStateChangeBroadcast(false);
+            }
+
+            @Override
+            public boolean processMessage(Message msg) {
+                switch (msg.what) {
+                    case NsdManager.ENABLE:
+                        transitionTo(mEnabledState);
+                        break;
+                    default:
+                        return NOT_HANDLED;
+                }
+                return HANDLED;
+            }
+        }
+
+        class EnabledState extends State {
+            @Override
+            public void enter() {
+                sendNsdStateChangeBroadcast(true);
+            }
+
+            @Override
+            public void exit() {
+                // TODO: it is incorrect to stop the daemon without expunging all requests
+                // and sending error callbacks to clients.
+                scheduleStop();
+            }
+
+            private boolean requestLimitReached(ClientInfo clientInfo) {
+                if (clientInfo.mClientIds.size() >= ClientInfo.MAX_LIMIT) {
+                    if (DBG) Log.d(TAG, "Exceeded max outstanding requests " + clientInfo);
+                    return true;
+                }
+                return false;
+            }
+
+            private void storeRequestMap(int clientId, int globalId, ClientInfo clientInfo, int what) {
+                clientInfo.mClientIds.put(clientId, globalId);
+                clientInfo.mClientRequests.put(clientId, what);
+                mIdToClientInfoMap.put(globalId, clientInfo);
+                // Remove the cleanup event because here comes a new request.
+                cancelStop();
+            }
+
+            private void removeRequestMap(int clientId, int globalId, ClientInfo clientInfo) {
+                clientInfo.mClientIds.delete(clientId);
+                clientInfo.mClientRequests.delete(clientId);
+                mIdToClientInfoMap.remove(globalId);
+                maybeScheduleStop();
+            }
+
+            @Override
+            public boolean processMessage(Message msg) {
+                final ClientInfo clientInfo;
+                final int id;
+                final int clientId = msg.arg2;
+                final ListenerArgs args;
+                switch (msg.what) {
+                    case NsdManager.DISABLE:
+                        //TODO: cleanup clients
+                        transitionTo(mDisabledState);
+                        break;
+                    case NsdManager.DISCOVER_SERVICES:
+                        if (DBG) Log.d(TAG, "Discover services");
+                        args = (ListenerArgs) msg.obj;
+                        clientInfo = mClients.get(args.connector);
+
+                        if (requestLimitReached(clientInfo)) {
+                            clientInfo.onDiscoverServicesFailed(
+                                    clientId, NsdManager.FAILURE_MAX_LIMIT);
+                            break;
+                        }
+
+                        maybeStartDaemon();
+                        id = getUniqueId();
+                        if (discoverServices(id, args.serviceInfo)) {
+                            if (DBG) {
+                                Log.d(TAG, "Discover " + msg.arg2 + " " + id
+                                        + args.serviceInfo.getServiceType());
+                            }
+                            storeRequestMap(clientId, id, clientInfo, msg.what);
+                            clientInfo.onDiscoverServicesStarted(clientId, args.serviceInfo);
+                        } else {
+                            stopServiceDiscovery(id);
+                            clientInfo.onDiscoverServicesFailed(clientId,
+                                    NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.STOP_DISCOVERY:
+                        if (DBG) Log.d(TAG, "Stop service discovery");
+                        args = (ListenerArgs) msg.obj;
+                        clientInfo = mClients.get(args.connector);
+
+                        try {
+                            id = clientInfo.mClientIds.get(clientId);
+                        } catch (NullPointerException e) {
+                            clientInfo.onStopDiscoveryFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                            break;
+                        }
+                        removeRequestMap(clientId, id, clientInfo);
+                        if (stopServiceDiscovery(id)) {
+                            clientInfo.onStopDiscoverySucceeded(clientId);
+                        } else {
+                            clientInfo.onStopDiscoveryFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.REGISTER_SERVICE:
+                        if (DBG) Log.d(TAG, "Register service");
+                        args = (ListenerArgs) msg.obj;
+                        clientInfo = mClients.get(args.connector);
+                        if (requestLimitReached(clientInfo)) {
+                            clientInfo.onRegisterServiceFailed(
+                                    clientId, NsdManager.FAILURE_MAX_LIMIT);
+                            break;
+                        }
+
+                        maybeStartDaemon();
+                        id = getUniqueId();
+                        if (registerService(id, args.serviceInfo)) {
+                            if (DBG) Log.d(TAG, "Register " + clientId + " " + id);
+                            storeRequestMap(clientId, id, clientInfo, msg.what);
+                            // Return success after mDns reports success
+                        } else {
+                            unregisterService(id);
+                            clientInfo.onRegisterServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.UNREGISTER_SERVICE:
+                        if (DBG) Log.d(TAG, "unregister service");
+                        args = (ListenerArgs) msg.obj;
+                        clientInfo = mClients.get(args.connector);
+                        if (clientInfo == null) {
+                            Log.e(TAG, "Unknown connector in unregistration");
+                            break;
+                        }
+                        id = clientInfo.mClientIds.get(clientId);
+                        removeRequestMap(clientId, id, clientInfo);
+                        if (unregisterService(id)) {
+                            clientInfo.onUnregisterServiceSucceeded(clientId);
+                        } else {
+                            clientInfo.onUnregisterServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.RESOLVE_SERVICE:
+                        if (DBG) Log.d(TAG, "Resolve service");
+                        args = (ListenerArgs) msg.obj;
+                        clientInfo = mClients.get(args.connector);
+
+                        if (clientInfo.mResolvedService != null) {
+                            clientInfo.onResolveServiceFailed(
+                                    clientId, NsdManager.FAILURE_ALREADY_ACTIVE);
+                            break;
+                        }
+
+                        maybeStartDaemon();
+                        id = getUniqueId();
+                        if (resolveService(id, args.serviceInfo)) {
+                            clientInfo.mResolvedService = new NsdServiceInfo();
+                            storeRequestMap(clientId, id, clientInfo, msg.what);
+                        } else {
+                            clientInfo.onResolveServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        break;
+                    case NsdManager.NATIVE_DAEMON_EVENT:
+                        NativeEvent event = (NativeEvent) msg.obj;
+                        if (!handleNativeEvent(event.code, event.raw, event.cooked)) {
+                            return NOT_HANDLED;
+                        }
+                        break;
+                    default:
+                        return NOT_HANDLED;
+                }
+                return HANDLED;
+            }
+
+            private boolean handleNativeEvent(int code, String raw, String[] cooked) {
+                NsdServiceInfo servInfo;
+                int id = Integer.parseInt(cooked[1]);
+                ClientInfo clientInfo = mIdToClientInfoMap.get(id);
+                if (clientInfo == null) {
+                    String name = NativeResponseCode.nameOf(code);
+                    Log.e(TAG, String.format("id %d for %s has no client mapping", id, name));
+                    return false;
+                }
+
+                /* This goes in response as msg.arg2 */
+                int clientId = clientInfo.getClientId(id);
+                if (clientId < 0) {
+                    // This can happen because of race conditions. For example,
+                    // SERVICE_FOUND may race with STOP_SERVICE_DISCOVERY,
+                    // and we may get in this situation.
+                    String name = NativeResponseCode.nameOf(code);
+                    Log.d(TAG, String.format(
+                            "Notification %s for listener id %d that is no longer active",
+                            name, id));
+                    return false;
+                }
+                if (DBG) {
+                    String name = NativeResponseCode.nameOf(code);
+                    Log.d(TAG, String.format("Native daemon message %s: %s", name, raw));
+                }
+                switch (code) {
+                    case NativeResponseCode.SERVICE_FOUND:
+                        /* NNN uniqueId serviceName regType domain interfaceIdx netId */
+                        servInfo = new NsdServiceInfo(cooked[2], cooked[3]);
+                        final int foundNetId;
+                        try {
+                            foundNetId = Integer.parseInt(cooked[6]);
+                        } catch (NumberFormatException e) {
+                            Log.wtf(TAG, "Invalid network received from mdnsd: " + cooked[6]);
+                            break;
+                        }
+                        if (foundNetId == 0L) {
+                            // Ignore services that do not have a Network: they are not usable
+                            // by apps, as they would need privileged permissions to use
+                            // interfaces that do not have an associated Network.
+                            break;
+                        }
+                        servInfo.setNetwork(new Network(foundNetId));
+                        clientInfo.onServiceFound(clientId, servInfo);
+                        break;
+                    case NativeResponseCode.SERVICE_LOST:
+                        /* NNN uniqueId serviceName regType domain interfaceIdx netId */
+                        final int lostNetId;
+                        try {
+                            lostNetId = Integer.parseInt(cooked[6]);
+                        } catch (NumberFormatException e) {
+                            Log.wtf(TAG, "Invalid network received from mdnsd: " + cooked[6]);
+                            break;
+                        }
+                        servInfo = new NsdServiceInfo(cooked[2], cooked[3]);
+                        // The network could be null if it was torn down when the service is lost
+                        // TODO: avoid returning null in that case, possibly by remembering found
+                        // services on the same interface index and their network at the time
+                        servInfo.setNetwork(lostNetId == 0 ? null : new Network(lostNetId));
+                        clientInfo.onServiceLost(clientId, servInfo);
+                        break;
+                    case NativeResponseCode.SERVICE_DISCOVERY_FAILED:
+                        /* NNN uniqueId errorCode */
+                        clientInfo.onDiscoverServicesFailed(
+                                clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        break;
+                    case NativeResponseCode.SERVICE_REGISTERED:
+                        /* NNN regId serviceName regType */
+                        servInfo = new NsdServiceInfo(cooked[2], null);
+                        clientInfo.onRegisterServiceSucceeded(clientId, servInfo);
+                        break;
+                    case NativeResponseCode.SERVICE_REGISTRATION_FAILED:
+                        /* NNN regId errorCode */
+                        clientInfo.onRegisterServiceFailed(
+                                clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        break;
+                    case NativeResponseCode.SERVICE_UPDATED:
+                        /* NNN regId */
+                        break;
+                    case NativeResponseCode.SERVICE_UPDATE_FAILED:
+                        /* NNN regId errorCode */
+                        break;
+                    case NativeResponseCode.SERVICE_RESOLVED:
+                        /* NNN resolveId fullName hostName port txtlen txtdata interfaceIdx */
+                        int index = 0;
+                        while (index < cooked[2].length() && cooked[2].charAt(index) != '.') {
+                            if (cooked[2].charAt(index) == '\\') {
+                                ++index;
+                            }
+                            ++index;
+                        }
+                        if (index >= cooked[2].length()) {
+                            Log.e(TAG, "Invalid service found " + raw);
+                            break;
+                        }
+
+                        String name = cooked[2].substring(0, index);
+                        String rest = cooked[2].substring(index);
+                        String type = rest.replace(".local.", "");
+
+                        name = unescape(name);
+
+                        clientInfo.mResolvedService.setServiceName(name);
+                        clientInfo.mResolvedService.setServiceType(type);
+                        clientInfo.mResolvedService.setPort(Integer.parseInt(cooked[4]));
+                        clientInfo.mResolvedService.setTxtRecords(cooked[6]);
+                        // Network will be added after SERVICE_GET_ADDR_SUCCESS
+
+                        stopResolveService(id);
+                        removeRequestMap(clientId, id, clientInfo);
+
+                        int id2 = getUniqueId();
+                        if (getAddrInfo(id2, cooked[3], cooked[7] /* interfaceIdx */)) {
+                            storeRequestMap(clientId, id2, clientInfo, NsdManager.RESOLVE_SERVICE);
+                        } else {
+                            clientInfo.onResolveServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                            clientInfo.mResolvedService = null;
+                        }
+                        break;
+                    case NativeResponseCode.SERVICE_RESOLUTION_FAILED:
+                        /* NNN resolveId errorCode */
+                        stopResolveService(id);
+                        removeRequestMap(clientId, id, clientInfo);
+                        clientInfo.mResolvedService = null;
+                        clientInfo.onResolveServiceFailed(
+                                clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        break;
+                    case NativeResponseCode.SERVICE_GET_ADDR_FAILED:
+                        /* NNN resolveId errorCode */
+                        stopGetAddrInfo(id);
+                        removeRequestMap(clientId, id, clientInfo);
+                        clientInfo.mResolvedService = null;
+                        clientInfo.onResolveServiceFailed(
+                                clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        break;
+                    case NativeResponseCode.SERVICE_GET_ADDR_SUCCESS:
+                        /* NNN resolveId hostname ttl addr interfaceIdx netId */
+                        Network network = null;
+                        try {
+                            final int netId = Integer.parseInt(cooked[6]);
+                            network = netId == 0L ? null : new Network(netId);
+                        } catch (NumberFormatException e) {
+                            Log.wtf(TAG, "Invalid network in GET_ADDR_SUCCESS: " + cooked[6], e);
+                        }
+
+                        InetAddress serviceHost = null;
+                        try {
+                            serviceHost = InetAddress.getByName(cooked[4]);
+                        } catch (UnknownHostException e) {
+                            Log.wtf(TAG, "Invalid host in GET_ADDR_SUCCESS", e);
+                        }
+
+                        // If the resolved service is on an interface without a network, consider it
+                        // as a failure: it would not be usable by apps as they would need
+                        // privileged permissions.
+                        if (network != null && serviceHost != null) {
+                            clientInfo.mResolvedService.setHost(serviceHost);
+                            clientInfo.mResolvedService.setNetwork(network);
+                            clientInfo.onResolveServiceSucceeded(
+                                    clientId, clientInfo.mResolvedService);
+                        } else {
+                            clientInfo.onResolveServiceFailed(
+                                    clientId, NsdManager.FAILURE_INTERNAL_ERROR);
+                        }
+                        stopGetAddrInfo(id);
+                        removeRequestMap(clientId, id, clientInfo);
+                        clientInfo.mResolvedService = null;
+                        break;
+                    default:
+                        return false;
+                }
+                return true;
+            }
+       }
+    }
+
+    private String unescape(String s) {
+        StringBuilder sb = new StringBuilder(s.length());
+        for (int i = 0; i < s.length(); ++i) {
+            char c = s.charAt(i);
+            if (c == '\\') {
+                if (++i >= s.length()) {
+                    Log.e(TAG, "Unexpected end of escape sequence in: " + s);
+                    break;
+                }
+                c = s.charAt(i);
+                if (c != '.' && c != '\\') {
+                    if (i + 2 >= s.length()) {
+                        Log.e(TAG, "Unexpected end of escape sequence in: " + s);
+                        break;
+                    }
+                    c = (char) ((c-'0') * 100 + (s.charAt(i+1)-'0') * 10 + (s.charAt(i+2)-'0'));
+                    i += 2;
+                }
+            }
+            sb.append(c);
+        }
+        return sb.toString();
+    }
+
+    @VisibleForTesting
+    NsdService(Context ctx, Handler handler, DaemonConnectionSupplier fn, long cleanupDelayMs) {
+        mCleanupDelayMs = cleanupDelayMs;
+        mContext = ctx;
+        mNsdStateMachine = new NsdStateMachine(TAG, handler);
+        mNsdStateMachine.start();
+        mDaemonCallback = new NativeCallbackReceiver();
+        mDaemon = fn.get(mDaemonCallback);
+    }
+
+    public static NsdService create(Context context) throws InterruptedException {
+        HandlerThread thread = new HandlerThread(TAG);
+        thread.start();
+        Handler handler = new Handler(thread.getLooper());
+        NsdService service =
+                new NsdService(context, handler, DaemonConnection::new, CLEANUP_DELAY_MS);
+        service.mDaemonCallback.awaitConnection();
+        return service;
+    }
+
+    @Override
+    public INsdServiceConnector connect(INsdManagerCallback cb) {
+        mContext.enforceCallingOrSelfPermission(android.Manifest.permission.INTERNET, "NsdService");
+        final INsdServiceConnector connector = new NsdServiceConnector();
+        mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                NsdManager.REGISTER_CLIENT, new Pair<>(connector, cb)));
+        return connector;
+    }
+
+    private static class ListenerArgs {
+        public final NsdServiceConnector connector;
+        public final NsdServiceInfo serviceInfo;
+        ListenerArgs(NsdServiceConnector connector, NsdServiceInfo serviceInfo) {
+            this.connector = connector;
+            this.serviceInfo = serviceInfo;
+        }
+    }
+
+    private class NsdServiceConnector extends INsdServiceConnector.Stub
+            implements IBinder.DeathRecipient  {
+        @Override
+        public void registerService(int listenerKey, NsdServiceInfo serviceInfo) {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.REGISTER_SERVICE, 0, listenerKey,
+                    new ListenerArgs(this, serviceInfo)));
+        }
+
+        @Override
+        public void unregisterService(int listenerKey) {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.UNREGISTER_SERVICE, 0, listenerKey,
+                    new ListenerArgs(this, null)));
+        }
+
+        @Override
+        public void discoverServices(int listenerKey, NsdServiceInfo serviceInfo) {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.DISCOVER_SERVICES, 0, listenerKey,
+                    new ListenerArgs(this, serviceInfo)));
+        }
+
+        @Override
+        public void stopDiscovery(int listenerKey) {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.STOP_DISCOVERY, 0, listenerKey, new ListenerArgs(this, null)));
+        }
+
+        @Override
+        public void resolveService(int listenerKey, NsdServiceInfo serviceInfo) {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.RESOLVE_SERVICE, 0, listenerKey,
+                    new ListenerArgs(this, serviceInfo)));
+        }
+
+        @Override
+        public void startDaemon() {
+            mNsdStateMachine.sendMessage(mNsdStateMachine.obtainMessage(
+                    NsdManager.DAEMON_STARTUP, new ListenerArgs(this, null)));
+        }
+
+        @Override
+        public void binderDied() {
+            mNsdStateMachine.sendMessage(
+                    mNsdStateMachine.obtainMessage(NsdManager.UNREGISTER_CLIENT, this));
+        }
+    }
+
+    private void sendNsdStateChangeBroadcast(boolean isEnabled) {
+        final Intent intent = new Intent(NsdManager.ACTION_NSD_STATE_CHANGED);
+        intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
+        int nsdState = isEnabled ? NsdManager.NSD_STATE_ENABLED : NsdManager.NSD_STATE_DISABLED;
+        intent.putExtra(NsdManager.EXTRA_NSD_STATE, nsdState);
+        mContext.sendStickyBroadcastAsUser(intent, UserHandle.ALL);
+    }
+
+    private int getUniqueId() {
+        if (++mUniqueId == INVALID_ID) return ++mUniqueId;
+        return mUniqueId;
+    }
+
+    /* These should be in sync with system/netd/server/ResponseCode.h */
+    static final class NativeResponseCode {
+        public static final int SERVICE_DISCOVERY_FAILED    =   602;
+        public static final int SERVICE_FOUND               =   603;
+        public static final int SERVICE_LOST                =   604;
+
+        public static final int SERVICE_REGISTRATION_FAILED =   605;
+        public static final int SERVICE_REGISTERED          =   606;
+
+        public static final int SERVICE_RESOLUTION_FAILED   =   607;
+        public static final int SERVICE_RESOLVED            =   608;
+
+        public static final int SERVICE_UPDATED             =   609;
+        public static final int SERVICE_UPDATE_FAILED       =   610;
+
+        public static final int SERVICE_GET_ADDR_FAILED     =   611;
+        public static final int SERVICE_GET_ADDR_SUCCESS    =   612;
+
+        private static final SparseArray<String> CODE_NAMES = new SparseArray<>();
+        static {
+            CODE_NAMES.put(SERVICE_DISCOVERY_FAILED, "SERVICE_DISCOVERY_FAILED");
+            CODE_NAMES.put(SERVICE_FOUND, "SERVICE_FOUND");
+            CODE_NAMES.put(SERVICE_LOST, "SERVICE_LOST");
+            CODE_NAMES.put(SERVICE_REGISTRATION_FAILED, "SERVICE_REGISTRATION_FAILED");
+            CODE_NAMES.put(SERVICE_REGISTERED, "SERVICE_REGISTERED");
+            CODE_NAMES.put(SERVICE_RESOLUTION_FAILED, "SERVICE_RESOLUTION_FAILED");
+            CODE_NAMES.put(SERVICE_RESOLVED, "SERVICE_RESOLVED");
+            CODE_NAMES.put(SERVICE_UPDATED, "SERVICE_UPDATED");
+            CODE_NAMES.put(SERVICE_UPDATE_FAILED, "SERVICE_UPDATE_FAILED");
+            CODE_NAMES.put(SERVICE_GET_ADDR_FAILED, "SERVICE_GET_ADDR_FAILED");
+            CODE_NAMES.put(SERVICE_GET_ADDR_SUCCESS, "SERVICE_GET_ADDR_SUCCESS");
+        }
+
+        static String nameOf(int code) {
+            String name = CODE_NAMES.get(code);
+            if (name == null) {
+                return Integer.toString(code);
+            }
+            return name;
+        }
+    }
+
+    private class NativeEvent {
+        final int code;
+        final String raw;
+        final String[] cooked;
+
+        NativeEvent(int code, String raw, String[] cooked) {
+            this.code = code;
+            this.raw = raw;
+            this.cooked = cooked;
+        }
+    }
+
+    class NativeCallbackReceiver implements INativeDaemonConnectorCallbacks {
+        private final CountDownLatch connected = new CountDownLatch(1);
+
+        public void awaitConnection() throws InterruptedException {
+            connected.await();
+        }
+
+        @Override
+        public void onDaemonConnected() {
+            connected.countDown();
+        }
+
+        @Override
+        public boolean onCheckHoldWakeLock(int code) {
+            return false;
+        }
+
+        @Override
+        public boolean onEvent(int code, String raw, String[] cooked) {
+            // TODO: NDC translates a message to a callback, we could enhance NDC to
+            // directly interact with a state machine through messages
+            NativeEvent event = new NativeEvent(code, raw, cooked);
+            mNsdStateMachine.sendMessage(NsdManager.NATIVE_DAEMON_EVENT, event);
+            return true;
+        }
+    }
+
+    interface DaemonConnectionSupplier {
+        DaemonConnection get(NativeCallbackReceiver callback);
+    }
+
+    @VisibleForTesting
+    public static class DaemonConnection {
+        final NativeDaemonConnector mNativeConnector;
+        boolean mIsStarted = false;
+
+        DaemonConnection(NativeCallbackReceiver callback) {
+            mNativeConnector = new NativeDaemonConnector(callback, "mdns", 10, MDNS_TAG, 25, null);
+            new Thread(mNativeConnector, MDNS_TAG).start();
+        }
+
+        /**
+         * Executes the specified cmd on the daemon.
+         */
+        public boolean execute(Object... args) {
+            if (DBG) {
+                Log.d(TAG, "mdnssd " + Arrays.toString(args));
+            }
+            try {
+                mNativeConnector.execute("mdnssd", args);
+            } catch (NativeDaemonConnectorException e) {
+                Log.e(TAG, "Failed to execute mdnssd " + Arrays.toString(args), e);
+                return false;
+            }
+            return true;
+        }
+
+        /**
+         * Starts the daemon if it is not already started.
+         */
+        public void maybeStart() {
+            if (mIsStarted) {
+                return;
+            }
+            execute("start-service");
+            mIsStarted = true;
+        }
+
+        /**
+         * Stops the daemon if it is started.
+         */
+        public void maybeStop() {
+            if (!mIsStarted) {
+                return;
+            }
+            execute("stop-service");
+            mIsStarted = false;
+        }
+    }
+
+    private boolean registerService(int regId, NsdServiceInfo service) {
+        if (DBG) {
+            Log.d(TAG, "registerService: " + regId + " " + service);
+        }
+        String name = service.getServiceName();
+        String type = service.getServiceType();
+        int port = service.getPort();
+        byte[] textRecord = service.getTxtRecord();
+        String record = Base64.encodeToString(textRecord, Base64.DEFAULT).replace("\n", "");
+        return mDaemon.execute("register", regId, name, type, port, record);
+    }
+
+    private boolean unregisterService(int regId) {
+        return mDaemon.execute("stop-register", regId);
+    }
+
+    private boolean updateService(int regId, DnsSdTxtRecord t) {
+        if (t == null) {
+            return false;
+        }
+        return mDaemon.execute("update", regId, t.size(), t.getRawData());
+    }
+
+    private boolean discoverServices(int discoveryId, NsdServiceInfo serviceInfo) {
+        final Network network = serviceInfo.getNetwork();
+        final int discoverInterface = getNetworkInterfaceIndex(network);
+        if (network != null && discoverInterface == IFACE_IDX_ANY) {
+            Log.e(TAG, "Interface to discover service on not found");
+            return false;
+        }
+        return mDaemon.execute("discover", discoveryId, serviceInfo.getServiceType(),
+                discoverInterface);
+    }
+
+    private boolean stopServiceDiscovery(int discoveryId) {
+        return mDaemon.execute("stop-discover", discoveryId);
+    }
+
+    private boolean resolveService(int resolveId, NsdServiceInfo service) {
+        final String name = service.getServiceName();
+        final String type = service.getServiceType();
+        final Network network = service.getNetwork();
+        final int resolveInterface = getNetworkInterfaceIndex(network);
+        if (network != null && resolveInterface == IFACE_IDX_ANY) {
+            Log.e(TAG, "Interface to resolve service on not found");
+            return false;
+        }
+        return mDaemon.execute("resolve", resolveId, name, type, "local.", resolveInterface);
+    }
+
+    /**
+     * Guess the interface to use to resolve or discover a service on a specific network.
+     *
+     * This is an imperfect guess, as for example the network may be gone or not yet fully
+     * registered. This is fine as failing is correct if the network is gone, and a client
+     * attempting to resolve/discover on a network not yet setup would have a bad time anyway; also
+     * this is to support the legacy mdnsresponder implementation, which historically resolved
+     * services on an unspecified network.
+     */
+    private int getNetworkInterfaceIndex(Network network) {
+        if (network == null) return IFACE_IDX_ANY;
+
+        final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+        if (cm == null) {
+            Log.wtf(TAG, "No ConnectivityManager for resolveService");
+            return IFACE_IDX_ANY;
+        }
+        final LinkProperties lp = cm.getLinkProperties(network);
+        if (lp == null) return IFACE_IDX_ANY;
+
+        // Only resolve on non-stacked interfaces
+        final NetworkInterface iface;
+        try {
+            iface = NetworkInterface.getByName(lp.getInterfaceName());
+        } catch (SocketException e) {
+            Log.e(TAG, "Error querying interface", e);
+            return IFACE_IDX_ANY;
+        }
+
+        if (iface == null) {
+            Log.e(TAG, "Interface not found: " + lp.getInterfaceName());
+            return IFACE_IDX_ANY;
+        }
+
+        return iface.getIndex();
+    }
+
+    private boolean stopResolveService(int resolveId) {
+        return mDaemon.execute("stop-resolve", resolveId);
+    }
+
+    private boolean getAddrInfo(int resolveId, String hostname, String interfaceIdx) {
+        // interfaceIdx is always obtained (as string) from the service resolved callback
+        return mDaemon.execute("getaddrinfo", resolveId, hostname, interfaceIdx);
+    }
+
+    private boolean stopGetAddrInfo(int resolveId) {
+        return mDaemon.execute("stop-getaddrinfo", resolveId);
+    }
+
+    @Override
+    public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+        if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.DUMP)
+                != PackageManager.PERMISSION_GRANTED) {
+            pw.println("Permission Denial: can't dump " + TAG
+                    + " due to missing android.permission.DUMP permission");
+            return;
+        }
+
+        for (ClientInfo client : mClients.values()) {
+            pw.println("Client Info");
+            pw.println(client);
+        }
+
+        mNsdStateMachine.dump(fd, pw, args);
+    }
+
+    /* Information tracked per client */
+    private class ClientInfo {
+
+        private static final int MAX_LIMIT = 10;
+        private final INsdManagerCallback mCb;
+        /* Remembers a resolved service until getaddrinfo completes */
+        private NsdServiceInfo mResolvedService;
+
+        /* A map from client id to unique id sent to mDns */
+        private final SparseIntArray mClientIds = new SparseIntArray();
+
+        /* A map from client id to the type of the request we had received */
+        private final SparseIntArray mClientRequests = new SparseIntArray();
+
+        // The target SDK of this client < Build.VERSION_CODES.S
+        private boolean mIsLegacy = false;
+
+        private ClientInfo(INsdManagerCallback cb) {
+            mCb = cb;
+            if (DBG) Log.d(TAG, "New client");
+        }
+
+        @Override
+        public String toString() {
+            StringBuilder sb = new StringBuilder();
+            sb.append("mResolvedService ").append(mResolvedService).append("\n");
+            sb.append("mIsLegacy ").append(mIsLegacy).append("\n");
+            for(int i = 0; i< mClientIds.size(); i++) {
+                int clientID = mClientIds.keyAt(i);
+                sb.append("clientId ").append(clientID).
+                    append(" mDnsId ").append(mClientIds.valueAt(i)).
+                    append(" type ").append(mClientRequests.get(clientID)).append("\n");
+            }
+            return sb.toString();
+        }
+
+        private boolean isLegacy() {
+            return mIsLegacy;
+        }
+
+        private void setLegacy() {
+            mIsLegacy = true;
+        }
+
+        // Remove any pending requests from the global map when we get rid of a client,
+        // and send cancellations to the daemon.
+        private void expungeAllRequests() {
+            int globalId, clientId, i;
+            // TODO: to keep handler responsive, do not clean all requests for that client at once.
+            for (i = 0; i < mClientIds.size(); i++) {
+                clientId = mClientIds.keyAt(i);
+                globalId = mClientIds.valueAt(i);
+                mIdToClientInfoMap.remove(globalId);
+                if (DBG) {
+                    Log.d(TAG, "Terminating client-ID " + clientId
+                            + " global-ID " + globalId + " type " + mClientRequests.get(clientId));
+                }
+                switch (mClientRequests.get(clientId)) {
+                    case NsdManager.DISCOVER_SERVICES:
+                        stopServiceDiscovery(globalId);
+                        break;
+                    case NsdManager.RESOLVE_SERVICE:
+                        stopResolveService(globalId);
+                        break;
+                    case NsdManager.REGISTER_SERVICE:
+                        unregisterService(globalId);
+                        break;
+                    default:
+                        break;
+                }
+            }
+            mClientIds.clear();
+            mClientRequests.clear();
+        }
+
+        // mClientIds is a sparse array of listener id -> mDnsClient id.  For a given mDnsClient id,
+        // return the corresponding listener id.  mDnsClient id is also called a global id.
+        private int getClientId(final int globalId) {
+            int idx = mClientIds.indexOfValue(globalId);
+            if (idx < 0) {
+                return idx;
+            }
+            return mClientIds.keyAt(idx);
+        }
+
+        void onDiscoverServicesStarted(int listenerKey, NsdServiceInfo info) {
+            try {
+                mCb.onDiscoverServicesStarted(listenerKey, info);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onDiscoverServicesStarted", e);
+            }
+        }
+
+        void onDiscoverServicesFailed(int listenerKey, int error) {
+            try {
+                mCb.onDiscoverServicesFailed(listenerKey, error);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onDiscoverServicesFailed", e);
+            }
+        }
+
+        void onServiceFound(int listenerKey, NsdServiceInfo info) {
+            try {
+                mCb.onServiceFound(listenerKey, info);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onServiceFound(", e);
+            }
+        }
+
+        void onServiceLost(int listenerKey, NsdServiceInfo info) {
+            try {
+                mCb.onServiceLost(listenerKey, info);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onServiceLost(", e);
+            }
+        }
+
+        void onStopDiscoveryFailed(int listenerKey, int error) {
+            try {
+                mCb.onStopDiscoveryFailed(listenerKey, error);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onStopDiscoveryFailed", e);
+            }
+        }
+
+        void onStopDiscoverySucceeded(int listenerKey) {
+            try {
+                mCb.onStopDiscoverySucceeded(listenerKey);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onStopDiscoverySucceeded", e);
+            }
+        }
+
+        void onRegisterServiceFailed(int listenerKey, int error) {
+            try {
+                mCb.onRegisterServiceFailed(listenerKey, error);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onRegisterServiceFailed", e);
+            }
+        }
+
+        void onRegisterServiceSucceeded(int listenerKey, NsdServiceInfo info) {
+            try {
+                mCb.onRegisterServiceSucceeded(listenerKey, info);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onRegisterServiceSucceeded", e);
+            }
+        }
+
+        void onUnregisterServiceFailed(int listenerKey, int error) {
+            try {
+                mCb.onUnregisterServiceFailed(listenerKey, error);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onUnregisterServiceFailed", e);
+            }
+        }
+
+        void onUnregisterServiceSucceeded(int listenerKey) {
+            try {
+                mCb.onUnregisterServiceSucceeded(listenerKey);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onUnregisterServiceSucceeded", e);
+            }
+        }
+
+        void onResolveServiceFailed(int listenerKey, int error) {
+            try {
+                mCb.onResolveServiceFailed(listenerKey, error);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onResolveServiceFailed", e);
+            }
+        }
+
+        void onResolveServiceSucceeded(int listenerKey, NsdServiceInfo info) {
+            try {
+                mCb.onResolveServiceSucceeded(listenerKey, info);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Error calling onResolveServiceSucceeded", e);
+            }
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetConfigStore.java b/service-t/src/com/android/server/ethernet/EthernetConfigStore.java
new file mode 100644
index 0000000..6b623f4
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetConfigStore.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import android.annotation.Nullable;
+import android.net.IpConfiguration;
+import android.os.Environment;
+import android.util.ArrayMap;
+
+import com.android.server.net.IpConfigStore;
+
+
+/**
+ * This class provides an API to store and manage Ethernet network configuration.
+ */
+public class EthernetConfigStore {
+    private static final String ipConfigFile = Environment.getDataDirectory() +
+            "/misc/ethernet/ipconfig.txt";
+
+    private IpConfigStore mStore = new IpConfigStore();
+    private ArrayMap<String, IpConfiguration> mIpConfigurations;
+    private IpConfiguration mIpConfigurationForDefaultInterface;
+    private final Object mSync = new Object();
+
+    public EthernetConfigStore() {
+        mIpConfigurations = new ArrayMap<>(0);
+    }
+
+    public void read() {
+        synchronized (mSync) {
+            ArrayMap<String, IpConfiguration> configs =
+                    IpConfigStore.readIpConfigurations(ipConfigFile);
+
+            // This configuration may exist in old file versions when there was only a single active
+            // Ethernet interface.
+            if (configs.containsKey("0")) {
+                mIpConfigurationForDefaultInterface = configs.remove("0");
+            }
+
+            mIpConfigurations = configs;
+        }
+    }
+
+    public void write(String iface, IpConfiguration config) {
+        boolean modified;
+
+        synchronized (mSync) {
+            if (config == null) {
+                modified = mIpConfigurations.remove(iface) != null;
+            } else {
+                IpConfiguration oldConfig = mIpConfigurations.put(iface, config);
+                modified = !config.equals(oldConfig);
+            }
+
+            if (modified) {
+                mStore.writeIpConfigurations(ipConfigFile, mIpConfigurations);
+            }
+        }
+    }
+
+    public ArrayMap<String, IpConfiguration> getIpConfigurations() {
+        synchronized (mSync) {
+            return new ArrayMap<>(mIpConfigurations);
+        }
+    }
+
+    @Nullable
+    public IpConfiguration getIpConfigurationForDefaultInterface() {
+        synchronized (mSync) {
+            return mIpConfigurationForDefaultInterface == null
+                    ? null : new IpConfiguration(mIpConfigurationForDefaultInterface);
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetNetworkAgent.java b/service-t/src/com/android/server/ethernet/EthernetNetworkAgent.java
new file mode 100644
index 0000000..57fbce7
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetNetworkAgent.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import android.content.Context;
+import android.net.LinkProperties;
+import android.net.NetworkAgent;
+import android.net.NetworkAgentConfig;
+import android.net.NetworkCapabilities;
+import android.net.NetworkProvider;
+import android.net.NetworkScore;
+import android.os.Looper;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+
+public class EthernetNetworkAgent extends NetworkAgent {
+
+    private static final String TAG = "EthernetNetworkAgent";
+
+    public interface Callbacks {
+        void onNetworkUnwanted();
+    }
+
+    private final Callbacks mCallbacks;
+
+    EthernetNetworkAgent(
+            @NonNull Context context,
+            @NonNull Looper looper,
+            @NonNull NetworkCapabilities nc,
+            @NonNull LinkProperties lp,
+            @NonNull NetworkAgentConfig config,
+            @Nullable NetworkProvider provider,
+            @NonNull Callbacks cb) {
+        super(context, looper, TAG, nc, lp, new NetworkScore.Builder().build(), config, provider);
+        mCallbacks = cb;
+    }
+
+    @Override
+    public void onNetworkUnwanted() {
+        mCallbacks.onNetworkUnwanted();
+    }
+
+    // sendLinkProperties is final in NetworkAgent, so it cannot be mocked.
+    public void sendLinkPropertiesImpl(LinkProperties lp) {
+        sendLinkProperties(lp);
+    }
+
+    public Callbacks getCallbacks() {
+        return mCallbacks;
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
new file mode 100644
index 0000000..d910629
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
@@ -0,0 +1,785 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.Context;
+import android.content.res.Resources;
+import android.net.ConnectivityManager;
+import android.net.ConnectivityResources;
+import android.net.EthernetManager;
+import android.net.EthernetNetworkSpecifier;
+import android.net.EthernetNetworkManagementException;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.IpConfiguration;
+import android.net.IpConfiguration.IpAssignment;
+import android.net.IpConfiguration.ProxySettings;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.NetworkAgentConfig;
+import android.net.NetworkCapabilities;
+import android.net.NetworkFactory;
+import android.net.NetworkProvider;
+import android.net.NetworkRequest;
+import android.net.NetworkSpecifier;
+import android.net.ip.IIpClient;
+import android.net.ip.IpClientCallbacks;
+import android.net.ip.IpClientManager;
+import android.net.ip.IpClientUtil;
+import android.net.shared.ProvisioningConfiguration;
+import android.os.ConditionVariable;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.RemoteException;
+import android.text.TextUtils;
+import android.util.AndroidRuntimeException;
+import android.util.Log;
+import android.util.SparseArray;
+
+import com.android.connectivity.resources.R;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.IndentingPrintWriter;
+import com.android.net.module.util.InterfaceParams;
+
+import java.io.FileDescriptor;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * {@link NetworkFactory} that represents Ethernet networks.
+ *
+ * This class reports a static network score of 70 when it is tracking an interface and that
+ * interface's link is up, and a score of 0 otherwise.
+ */
+public class EthernetNetworkFactory extends NetworkFactory {
+    private final static String TAG = EthernetNetworkFactory.class.getSimpleName();
+    final static boolean DBG = true;
+
+    private final static int NETWORK_SCORE = 70;
+    private static final String NETWORK_TYPE = "Ethernet";
+    private static final String LEGACY_TCP_BUFFER_SIZES =
+            "524288,1048576,3145728,524288,1048576,2097152";
+
+    private final ConcurrentHashMap<String, NetworkInterfaceState> mTrackingInterfaces =
+            new ConcurrentHashMap<>();
+    private final Handler mHandler;
+    private final Context mContext;
+    final Dependencies mDeps;
+
+    public static class Dependencies {
+        public void makeIpClient(Context context, String iface, IpClientCallbacks callbacks) {
+            IpClientUtil.makeIpClient(context, iface, callbacks);
+        }
+
+        public IpClientManager makeIpClientManager(@NonNull final IIpClient ipClient) {
+            return new IpClientManager(ipClient, TAG);
+        }
+
+        public EthernetNetworkAgent makeEthernetNetworkAgent(Context context, Looper looper,
+                NetworkCapabilities nc, LinkProperties lp, NetworkAgentConfig config,
+                NetworkProvider provider, EthernetNetworkAgent.Callbacks cb) {
+            return new EthernetNetworkAgent(context, looper, nc, lp, config, provider, cb);
+        }
+
+        public InterfaceParams getNetworkInterfaceByName(String name) {
+            return InterfaceParams.getByName(name);
+        }
+
+        // TODO: remove legacy resource fallback after migrating its overlays.
+        private String getPlatformTcpBufferSizes(Context context) {
+            final Resources r = context.getResources();
+            final int resId = r.getIdentifier("config_ethernet_tcp_buffers", "string",
+                    context.getPackageName());
+            return r.getString(resId);
+        }
+
+        public String getTcpBufferSizesFromResource(Context context) {
+            final String tcpBufferSizes;
+            final String platformTcpBufferSizes = getPlatformTcpBufferSizes(context);
+            if (!LEGACY_TCP_BUFFER_SIZES.equals(platformTcpBufferSizes)) {
+                // Platform resource is not the historical default: use the overlay.
+                tcpBufferSizes = platformTcpBufferSizes;
+            } else {
+                final ConnectivityResources resources = new ConnectivityResources(context);
+                tcpBufferSizes = resources.get().getString(R.string.config_ethernet_tcp_buffers);
+            }
+            return tcpBufferSizes;
+        }
+    }
+
+    public static class ConfigurationException extends AndroidRuntimeException {
+        public ConfigurationException(String msg) {
+            super(msg);
+        }
+    }
+
+    public EthernetNetworkFactory(Handler handler, Context context) {
+        this(handler, context, new Dependencies());
+    }
+
+    @VisibleForTesting
+    EthernetNetworkFactory(Handler handler, Context context, Dependencies deps) {
+        super(handler.getLooper(), context, NETWORK_TYPE, createDefaultNetworkCapabilities());
+
+        mHandler = handler;
+        mContext = context;
+        mDeps = deps;
+
+        setScoreFilter(NETWORK_SCORE);
+    }
+
+    @Override
+    public boolean acceptRequest(NetworkRequest request) {
+        if (DBG) {
+            Log.d(TAG, "acceptRequest, request: " + request);
+        }
+
+        return networkForRequest(request) != null;
+    }
+
+    @Override
+    protected void needNetworkFor(NetworkRequest networkRequest) {
+        NetworkInterfaceState network = networkForRequest(networkRequest);
+
+        if (network == null) {
+            Log.e(TAG, "needNetworkFor, failed to get a network for " + networkRequest);
+            return;
+        }
+
+        if (++network.refCount == 1) {
+            network.start();
+        }
+    }
+
+    @Override
+    protected void releaseNetworkFor(NetworkRequest networkRequest) {
+        NetworkInterfaceState network = networkForRequest(networkRequest);
+        if (network == null) {
+            Log.e(TAG, "releaseNetworkFor, failed to get a network for " + networkRequest);
+            return;
+        }
+
+        if (--network.refCount == 0) {
+            network.stop();
+        }
+    }
+
+    /**
+     * Returns an array of available interface names. The array is sorted: unrestricted interfaces
+     * goes first, then sorted by name.
+     */
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected String[] getAvailableInterfaces(boolean includeRestricted) {
+        return mTrackingInterfaces.values()
+                .stream()
+                .filter(iface -> !iface.isRestricted() || includeRestricted)
+                .sorted((iface1, iface2) -> {
+                    int r = Boolean.compare(iface1.isRestricted(), iface2.isRestricted());
+                    return r == 0 ? iface1.name.compareTo(iface2.name) : r;
+                })
+                .map(iface -> iface.name)
+                .toArray(String[]::new);
+    }
+
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected void addInterface(@NonNull final String ifaceName, @NonNull final String hwAddress,
+            @NonNull final IpConfiguration ipConfig,
+            @NonNull final NetworkCapabilities capabilities) {
+        if (mTrackingInterfaces.containsKey(ifaceName)) {
+            Log.e(TAG, "Interface with name " + ifaceName + " already exists.");
+            return;
+        }
+
+        final NetworkCapabilities nc = new NetworkCapabilities.Builder(capabilities)
+                .setNetworkSpecifier(new EthernetNetworkSpecifier(ifaceName))
+                .build();
+
+        if (DBG) {
+            Log.d(TAG, "addInterface, iface: " + ifaceName + ", capabilities: " + nc);
+        }
+
+        final NetworkInterfaceState iface = new NetworkInterfaceState(
+                ifaceName, hwAddress, mHandler, mContext, ipConfig, nc, this, mDeps);
+        mTrackingInterfaces.put(ifaceName, iface);
+        updateCapabilityFilter();
+    }
+
+    @VisibleForTesting
+    protected int getInterfaceState(@NonNull String iface) {
+        final NetworkInterfaceState interfaceState = mTrackingInterfaces.get(iface);
+        if (interfaceState == null) {
+            return EthernetManager.STATE_ABSENT;
+        } else if (!interfaceState.mLinkUp) {
+            return EthernetManager.STATE_LINK_DOWN;
+        } else {
+            return EthernetManager.STATE_LINK_UP;
+        }
+    }
+
+    /**
+     * Update a network's configuration and restart it if necessary.
+     *
+     * @param ifaceName the interface name of the network to be updated.
+     * @param ipConfig the desired {@link IpConfiguration} for the given network or null. If
+     *                 {@code null} is passed, the existing IpConfiguration is not updated.
+     * @param capabilities the desired {@link NetworkCapabilities} for the given network. If
+     *                     {@code null} is passed, then the network's current
+     *                     {@link NetworkCapabilities} will be used in support of existing APIs as
+     *                     the public API does not allow this.
+     * @param listener an optional {@link INetworkInterfaceOutcomeReceiver} to notify callers of
+     *                 completion.
+     */
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected void updateInterface(@NonNull final String ifaceName,
+            @Nullable final IpConfiguration ipConfig,
+            @Nullable final NetworkCapabilities capabilities,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        if (!hasInterface(ifaceName)) {
+            maybeSendNetworkManagementCallbackForUntracked(ifaceName, listener);
+            return;
+        }
+
+        final NetworkInterfaceState iface = mTrackingInterfaces.get(ifaceName);
+        iface.updateInterface(ipConfig, capabilities, listener);
+        mTrackingInterfaces.put(ifaceName, iface);
+        updateCapabilityFilter();
+    }
+
+    private static NetworkCapabilities mixInCapabilities(NetworkCapabilities nc,
+            NetworkCapabilities addedNc) {
+       final NetworkCapabilities.Builder builder = new NetworkCapabilities.Builder(nc);
+       for (int transport : addedNc.getTransportTypes()) builder.addTransportType(transport);
+       for (int capability : addedNc.getCapabilities()) builder.addCapability(capability);
+       return builder.build();
+    }
+
+    private void updateCapabilityFilter() {
+        NetworkCapabilities capabilitiesFilter = createDefaultNetworkCapabilities();
+        for (NetworkInterfaceState iface:  mTrackingInterfaces.values()) {
+            capabilitiesFilter = mixInCapabilities(capabilitiesFilter, iface.mCapabilities);
+        }
+
+        if (DBG) Log.d(TAG, "updateCapabilityFilter: " + capabilitiesFilter);
+        setCapabilityFilter(capabilitiesFilter);
+    }
+
+    private static NetworkCapabilities createDefaultNetworkCapabilities() {
+        return NetworkCapabilities.Builder
+                .withoutDefaultCapabilities()
+                .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET).build();
+    }
+
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected void removeInterface(String interfaceName) {
+        NetworkInterfaceState iface = mTrackingInterfaces.remove(interfaceName);
+        if (iface != null) {
+            iface.maybeSendNetworkManagementCallbackForAbort();
+            iface.stop();
+        }
+
+        updateCapabilityFilter();
+    }
+
+    /** Returns true if state has been modified */
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected boolean updateInterfaceLinkState(@NonNull final String ifaceName, final boolean up,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        if (!hasInterface(ifaceName)) {
+            maybeSendNetworkManagementCallbackForUntracked(ifaceName, listener);
+            return false;
+        }
+
+        if (DBG) {
+            Log.d(TAG, "updateInterfaceLinkState, iface: " + ifaceName + ", up: " + up);
+        }
+
+        NetworkInterfaceState iface = mTrackingInterfaces.get(ifaceName);
+        return iface.updateLinkState(up, listener);
+    }
+
+    private void maybeSendNetworkManagementCallbackForUntracked(
+            String ifaceName, INetworkInterfaceOutcomeReceiver listener) {
+        maybeSendNetworkManagementCallback(listener, null,
+                new EthernetNetworkManagementException(
+                        ifaceName + " can't be updated as it is not available."));
+    }
+
+    @VisibleForTesting
+    protected boolean hasInterface(String ifaceName) {
+        return mTrackingInterfaces.containsKey(ifaceName);
+    }
+
+    private NetworkInterfaceState networkForRequest(NetworkRequest request) {
+        String requestedIface = null;
+
+        NetworkSpecifier specifier = request.getNetworkSpecifier();
+        if (specifier instanceof EthernetNetworkSpecifier) {
+            requestedIface = ((EthernetNetworkSpecifier) specifier)
+                .getInterfaceName();
+        }
+
+        NetworkInterfaceState network = null;
+        if (!TextUtils.isEmpty(requestedIface)) {
+            NetworkInterfaceState n = mTrackingInterfaces.get(requestedIface);
+            if (n != null && request.canBeSatisfiedBy(n.mCapabilities)) {
+                network = n;
+            }
+        } else {
+            for (NetworkInterfaceState n : mTrackingInterfaces.values()) {
+                if (request.canBeSatisfiedBy(n.mCapabilities) && n.mLinkUp) {
+                    network = n;
+                    break;
+                }
+            }
+        }
+
+        if (DBG) {
+            Log.i(TAG, "networkForRequest, request: " + request + ", network: " + network);
+        }
+
+        return network;
+    }
+
+    private static void maybeSendNetworkManagementCallback(
+            @Nullable final INetworkInterfaceOutcomeReceiver listener,
+            @Nullable final String iface,
+            @Nullable final EthernetNetworkManagementException e) {
+        if (null == listener) {
+            return;
+        }
+
+        try {
+            if (iface != null) {
+                listener.onResult(iface);
+            } else {
+                listener.onError(e);
+            }
+        } catch (RemoteException re) {
+            Log.e(TAG, "Can't send onComplete for network management callback", re);
+        }
+    }
+
+    @VisibleForTesting
+    static class NetworkInterfaceState {
+        final String name;
+
+        private final String mHwAddress;
+        private final Handler mHandler;
+        private final Context mContext;
+        private final NetworkFactory mNetworkFactory;
+        private final Dependencies mDeps;
+
+        private static String sTcpBufferSizes = null;  // Lazy initialized.
+
+        private boolean mLinkUp;
+        private int mLegacyType;
+        private LinkProperties mLinkProperties = new LinkProperties();
+
+        private volatile @Nullable IpClientManager mIpClient;
+        private @NonNull NetworkCapabilities mCapabilities;
+        private @Nullable EthernetIpClientCallback mIpClientCallback;
+        private @Nullable EthernetNetworkAgent mNetworkAgent;
+        private @Nullable IpConfiguration mIpConfig;
+
+        /**
+         * A map of TRANSPORT_* types to legacy transport types available for each type an ethernet
+         * interface could propagate.
+         *
+         * There are no legacy type equivalents to LOWPAN or WIFI_AWARE. These types are set to
+         * TYPE_NONE to match the behavior of their own network factories.
+         */
+        private static final SparseArray<Integer> sTransports = new SparseArray();
+        static {
+            sTransports.put(NetworkCapabilities.TRANSPORT_ETHERNET,
+                    ConnectivityManager.TYPE_ETHERNET);
+            sTransports.put(NetworkCapabilities.TRANSPORT_BLUETOOTH,
+                    ConnectivityManager.TYPE_BLUETOOTH);
+            sTransports.put(NetworkCapabilities.TRANSPORT_WIFI, ConnectivityManager.TYPE_WIFI);
+            sTransports.put(NetworkCapabilities.TRANSPORT_CELLULAR,
+                    ConnectivityManager.TYPE_MOBILE);
+            sTransports.put(NetworkCapabilities.TRANSPORT_LOWPAN, ConnectivityManager.TYPE_NONE);
+            sTransports.put(NetworkCapabilities.TRANSPORT_WIFI_AWARE,
+                    ConnectivityManager.TYPE_NONE);
+        }
+
+        long refCount = 0;
+
+        private class EthernetIpClientCallback extends IpClientCallbacks {
+            private final ConditionVariable mIpClientStartCv = new ConditionVariable(false);
+            private final ConditionVariable mIpClientShutdownCv = new ConditionVariable(false);
+            @Nullable INetworkInterfaceOutcomeReceiver mNetworkManagementListener;
+
+            EthernetIpClientCallback(@Nullable final INetworkInterfaceOutcomeReceiver listener) {
+                mNetworkManagementListener = listener;
+            }
+
+            @Override
+            public void onIpClientCreated(IIpClient ipClient) {
+                mIpClient = mDeps.makeIpClientManager(ipClient);
+                mIpClientStartCv.open();
+            }
+
+            private void awaitIpClientStart() {
+                mIpClientStartCv.block();
+            }
+
+            private void awaitIpClientShutdown() {
+                mIpClientShutdownCv.block();
+            }
+
+            // At the time IpClient is stopped, an IpClient event may have already been posted on
+            // the back of the handler and is awaiting execution. Once that event is executed, the
+            // associated callback object may not be valid anymore
+            // (NetworkInterfaceState#mIpClientCallback points to a different object / null).
+            private boolean isCurrentCallback() {
+                return this == mIpClientCallback;
+            }
+
+            private void handleIpEvent(final @NonNull Runnable r) {
+                mHandler.post(() -> {
+                    if (!isCurrentCallback()) {
+                        Log.i(TAG, "Ignoring stale IpClientCallbacks " + this);
+                        return;
+                    }
+                    r.run();
+                });
+            }
+
+            @Override
+            public void onProvisioningSuccess(LinkProperties newLp) {
+                handleIpEvent(() -> onIpLayerStarted(newLp, mNetworkManagementListener));
+            }
+
+            @Override
+            public void onProvisioningFailure(LinkProperties newLp) {
+                // This cannot happen due to provisioning timeout, because our timeout is 0. It can
+                // happen due to errors while provisioning or on provisioning loss.
+                handleIpEvent(() -> onIpLayerStopped(mNetworkManagementListener));
+            }
+
+            @Override
+            public void onLinkPropertiesChange(LinkProperties newLp) {
+                handleIpEvent(() -> updateLinkProperties(newLp));
+            }
+
+            @Override
+            public void onReachabilityLost(String logMsg) {
+                handleIpEvent(() -> updateNeighborLostEvent(logMsg));
+            }
+
+            @Override
+            public void onQuit() {
+                mIpClient = null;
+                mIpClientShutdownCv.open();
+            }
+        }
+
+        NetworkInterfaceState(String ifaceName, String hwAddress, Handler handler, Context context,
+                @NonNull IpConfiguration ipConfig, @NonNull NetworkCapabilities capabilities,
+                NetworkFactory networkFactory, Dependencies deps) {
+            name = ifaceName;
+            mIpConfig = Objects.requireNonNull(ipConfig);
+            mCapabilities = Objects.requireNonNull(capabilities);
+            mLegacyType = getLegacyType(mCapabilities);
+            mHandler = handler;
+            mContext = context;
+            mNetworkFactory = networkFactory;
+            mDeps = deps;
+            mHwAddress = hwAddress;
+        }
+
+        /**
+         * Determines the legacy transport type from a NetworkCapabilities transport type. Defaults
+         * to legacy TYPE_NONE if there is no known conversion
+         */
+        private static int getLegacyType(int transport) {
+            return sTransports.get(transport, ConnectivityManager.TYPE_NONE);
+        }
+
+        private static int getLegacyType(@NonNull final NetworkCapabilities capabilities) {
+            final int[] transportTypes = capabilities.getTransportTypes();
+            if (transportTypes.length > 0) {
+                return getLegacyType(transportTypes[0]);
+            }
+
+            // Should never happen as transport is always one of ETHERNET or a valid override
+            throw new ConfigurationException("Network Capabilities do not have an associated "
+                    + "transport type.");
+        }
+
+        private void setCapabilities(@NonNull final NetworkCapabilities capabilities) {
+            mCapabilities = new NetworkCapabilities(capabilities);
+            mLegacyType = getLegacyType(mCapabilities);
+        }
+
+        void updateInterface(@Nullable final IpConfiguration ipConfig,
+                @Nullable final NetworkCapabilities capabilities,
+                @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            if (DBG) {
+                Log.d(TAG, "updateInterface, iface: " + name
+                        + ", ipConfig: " + ipConfig + ", old ipConfig: " + mIpConfig
+                        + ", capabilities: " + capabilities + ", old capabilities: " + mCapabilities
+                        + ", listener: " + listener
+                );
+            }
+
+            if (null != ipConfig){
+                mIpConfig = ipConfig;
+            }
+            if (null != capabilities) {
+                setCapabilities(capabilities);
+            }
+            // Send an abort callback if a request is filed before the previous one has completed.
+            maybeSendNetworkManagementCallbackForAbort();
+            // TODO: Update this logic to only do a restart if required. Although a restart may
+            //  be required due to the capabilities or ipConfiguration values, not all
+            //  capabilities changes require a restart.
+            restart(listener);
+        }
+
+        boolean isRestricted() {
+            return !mCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
+        }
+
+        private void start() {
+            start(null);
+        }
+
+        private void start(@Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            if (mIpClient != null) {
+                if (DBG) Log.d(TAG, "IpClient already started");
+                return;
+            }
+            if (DBG) {
+                Log.d(TAG, String.format("Starting Ethernet IpClient(%s)", name));
+            }
+
+            mIpClientCallback = new EthernetIpClientCallback(listener);
+            mDeps.makeIpClient(mContext, name, mIpClientCallback);
+            mIpClientCallback.awaitIpClientStart();
+
+            if (sTcpBufferSizes == null) {
+                sTcpBufferSizes = mDeps.getTcpBufferSizesFromResource(mContext);
+            }
+            provisionIpClient(mIpClient, mIpConfig, sTcpBufferSizes);
+        }
+
+        void onIpLayerStarted(@NonNull final LinkProperties linkProperties,
+                @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            if (mNetworkAgent != null) {
+                Log.e(TAG, "Already have a NetworkAgent - aborting new request");
+                stop();
+                return;
+            }
+            mLinkProperties = linkProperties;
+
+            // Create our NetworkAgent.
+            final NetworkAgentConfig config = new NetworkAgentConfig.Builder()
+                    .setLegacyType(mLegacyType)
+                    .setLegacyTypeName(NETWORK_TYPE)
+                    .setLegacyExtraInfo(mHwAddress)
+                    .build();
+            mNetworkAgent = mDeps.makeEthernetNetworkAgent(mContext, mHandler.getLooper(),
+                    mCapabilities, mLinkProperties, config, mNetworkFactory.getProvider(),
+                    new EthernetNetworkAgent.Callbacks() {
+                        @Override
+                        public void onNetworkUnwanted() {
+                            // if mNetworkAgent is null, we have already called stop.
+                            if (mNetworkAgent == null) return;
+
+                            if (this == mNetworkAgent.getCallbacks()) {
+                                stop();
+                            } else {
+                                Log.d(TAG, "Ignoring unwanted as we have a more modern " +
+                                        "instance");
+                            }
+                        }
+                    });
+            mNetworkAgent.register();
+            mNetworkAgent.markConnected();
+            realizeNetworkManagementCallback(name, null);
+        }
+
+        void onIpLayerStopped(@Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            // There is no point in continuing if the interface is gone as stop() will be triggered
+            // by removeInterface() when processed on the handler thread and start() won't
+            // work for a non-existent interface.
+            if (null == mDeps.getNetworkInterfaceByName(name)) {
+                if (DBG) Log.d(TAG, name + " is no longer available.");
+                // Send a callback in case a provisioning request was in progress.
+                maybeSendNetworkManagementCallbackForAbort();
+                return;
+            }
+            restart(listener);
+        }
+
+        private void maybeSendNetworkManagementCallbackForAbort() {
+            realizeNetworkManagementCallback(null,
+                    new EthernetNetworkManagementException(
+                            "The IP provisioning request has been aborted."));
+        }
+
+        // Must be called on the handler thread
+        private void realizeNetworkManagementCallback(@Nullable final String iface,
+                @Nullable final EthernetNetworkManagementException e) {
+            ensureRunningOnEthernetHandlerThread();
+            if (null == mIpClientCallback) {
+                return;
+            }
+
+            EthernetNetworkFactory.maybeSendNetworkManagementCallback(
+                    mIpClientCallback.mNetworkManagementListener, iface, e);
+            // Only send a single callback per listener.
+            mIpClientCallback.mNetworkManagementListener = null;
+        }
+
+        private void ensureRunningOnEthernetHandlerThread() {
+            if (mHandler.getLooper().getThread() != Thread.currentThread()) {
+                throw new IllegalStateException(
+                        "Not running on the Ethernet thread: "
+                                + Thread.currentThread().getName());
+            }
+        }
+
+        void updateLinkProperties(LinkProperties linkProperties) {
+            mLinkProperties = linkProperties;
+            if (mNetworkAgent != null) {
+                mNetworkAgent.sendLinkPropertiesImpl(linkProperties);
+            }
+        }
+
+        void updateNeighborLostEvent(String logMsg) {
+            Log.i(TAG, "updateNeighborLostEvent " + logMsg);
+            // Reachability lost will be seen only if the gateway is not reachable.
+            // Since ethernet FW doesn't have the mechanism to scan for new networks
+            // like WiFi, simply restart.
+            // If there is a better network, that will become default and apps
+            // will be able to use internet. If ethernet gets connected again,
+            // and has backhaul connectivity, it will become default.
+            restart();
+        }
+
+        /** Returns true if state has been modified */
+        boolean updateLinkState(final boolean up,
+                @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            if (mLinkUp == up)  {
+                EthernetNetworkFactory.maybeSendNetworkManagementCallback(listener, null,
+                        new EthernetNetworkManagementException(
+                                "No changes with requested link state " + up + " for " + name));
+                return false;
+            }
+            mLinkUp = up;
+
+            if (!up) { // was up, goes down
+                // Send an abort on a provisioning request callback if necessary before stopping.
+                maybeSendNetworkManagementCallbackForAbort();
+                stop();
+                // If only setting the interface down, send a callback to signal completion.
+                EthernetNetworkFactory.maybeSendNetworkManagementCallback(listener, name, null);
+            } else { // was down, goes up
+                stop();
+                start(listener);
+            }
+
+            return true;
+        }
+
+        void stop() {
+            // Invalidate all previous start requests
+            if (mIpClient != null) {
+                mIpClient.shutdown();
+                mIpClientCallback.awaitIpClientShutdown();
+                mIpClient = null;
+            }
+            mIpClientCallback = null;
+
+            if (mNetworkAgent != null) {
+                mNetworkAgent.unregister();
+                mNetworkAgent = null;
+            }
+            mLinkProperties.clear();
+        }
+
+        private static void provisionIpClient(@NonNull final IpClientManager ipClient,
+                @NonNull final IpConfiguration config, @NonNull final String tcpBufferSizes) {
+            if (config.getProxySettings() == ProxySettings.STATIC ||
+                    config.getProxySettings() == ProxySettings.PAC) {
+                ipClient.setHttpProxy(config.getHttpProxy());
+            }
+
+            if (!TextUtils.isEmpty(tcpBufferSizes)) {
+                ipClient.setTcpBufferSizes(tcpBufferSizes);
+            }
+
+            ipClient.startProvisioning(createProvisioningConfiguration(config));
+        }
+
+        private static ProvisioningConfiguration createProvisioningConfiguration(
+                @NonNull final IpConfiguration config) {
+            if (config.getIpAssignment() == IpAssignment.STATIC) {
+                return new ProvisioningConfiguration.Builder()
+                        .withStaticConfiguration(config.getStaticIpConfiguration())
+                        .build();
+            }
+            return new ProvisioningConfiguration.Builder()
+                        .withProvisioningTimeoutMs(0)
+                        .build();
+        }
+
+        void restart() {
+            restart(null);
+        }
+
+        void restart(@Nullable final INetworkInterfaceOutcomeReceiver listener) {
+            if (DBG) Log.d(TAG, "reconnecting Ethernet");
+            stop();
+            start(listener);
+        }
+
+        @Override
+        public String toString() {
+            return getClass().getSimpleName() + "{ "
+                    + "refCount: " + refCount + ", "
+                    + "iface: " + name + ", "
+                    + "up: " + mLinkUp + ", "
+                    + "hwAddress: " + mHwAddress + ", "
+                    + "networkCapabilities: " + mCapabilities + ", "
+                    + "networkAgent: " + mNetworkAgent + ", "
+                    + "ipClient: " + mIpClient + ","
+                    + "linkProperties: " + mLinkProperties
+                    + "}";
+        }
+    }
+
+    void dump(FileDescriptor fd, IndentingPrintWriter pw, String[] args) {
+        super.dump(fd, pw, args);
+        pw.println(getClass().getSimpleName());
+        pw.println("Tracking interfaces:");
+        pw.increaseIndent();
+        for (String iface: mTrackingInterfaces.keySet()) {
+            NetworkInterfaceState ifaceState = mTrackingInterfaces.get(iface);
+            pw.println(iface + ":" + ifaceState);
+            pw.increaseIndent();
+            if (null == ifaceState.mIpClient) {
+                pw.println("IpClient is null");
+            }
+            pw.decreaseIndent();
+        }
+        pw.decreaseIndent();
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetService.java b/service-t/src/com/android/server/ethernet/EthernetService.java
new file mode 100644
index 0000000..d405fd5
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetService.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import android.content.Context;
+import android.net.INetd;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.IBinder;
+
+import java.util.Objects;
+
+// TODO: consider renaming EthernetServiceImpl to EthernetService and deleting this file.
+public final class EthernetService {
+    private static final String TAG = "EthernetService";
+    private static final String THREAD_NAME = "EthernetServiceThread";
+
+    private static INetd getNetd(Context context) {
+        final INetd netd =
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE));
+        Objects.requireNonNull(netd, "could not get netd instance");
+        return netd;
+    }
+
+    public static EthernetServiceImpl create(Context context) {
+        final HandlerThread handlerThread = new HandlerThread(THREAD_NAME);
+        handlerThread.start();
+        final Handler handler = new Handler(handlerThread.getLooper());
+        final EthernetNetworkFactory factory = new EthernetNetworkFactory(handler, context);
+        return new EthernetServiceImpl(context, handler,
+                new EthernetTracker(context, handler, factory, getNetd(context)));
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
new file mode 100644
index 0000000..5e830ad
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import static android.net.NetworkCapabilities.TRANSPORT_TEST;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.net.IEthernetManager;
+import android.net.IEthernetServiceListener;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.ITetheredInterfaceCallback;
+import android.net.EthernetNetworkUpdateRequest;
+import android.net.IpConfiguration;
+import android.net.NetworkCapabilities;
+import android.os.Binder;
+import android.os.Handler;
+import android.os.RemoteException;
+import android.util.Log;
+import android.util.PrintWriterPrinter;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.IndentingPrintWriter;
+import com.android.net.module.util.PermissionUtils;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * EthernetServiceImpl handles remote Ethernet operation requests by implementing
+ * the IEthernetManager interface.
+ */
+public class EthernetServiceImpl extends IEthernetManager.Stub {
+    private static final String TAG = "EthernetServiceImpl";
+
+    @VisibleForTesting
+    final AtomicBoolean mStarted = new AtomicBoolean(false);
+    private final Context mContext;
+    private final Handler mHandler;
+    private final EthernetTracker mTracker;
+
+    EthernetServiceImpl(@NonNull final Context context, @NonNull final Handler handler,
+            @NonNull final EthernetTracker tracker) {
+        mContext = context;
+        mHandler = handler;
+        mTracker = tracker;
+    }
+
+    private void enforceAutomotiveDevice(final @NonNull String methodName) {
+        PermissionUtils.enforceSystemFeature(mContext, PackageManager.FEATURE_AUTOMOTIVE,
+                methodName + " is only available on automotive devices.");
+    }
+
+    private boolean checkUseRestrictedNetworksPermission() {
+        return PermissionUtils.checkAnyPermissionOf(mContext,
+                android.Manifest.permission.CONNECTIVITY_USE_RESTRICTED_NETWORKS);
+    }
+
+    public void start() {
+        Log.i(TAG, "Starting Ethernet service");
+        mTracker.start();
+        mStarted.set(true);
+    }
+
+    private void throwIfEthernetNotStarted() {
+        if (!mStarted.get()) {
+            throw new IllegalStateException("System isn't ready to change ethernet configurations");
+        }
+    }
+
+    @Override
+    public String[] getAvailableInterfaces() throws RemoteException {
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        return mTracker.getInterfaces(checkUseRestrictedNetworksPermission());
+    }
+
+    /**
+     * Get Ethernet configuration
+     * @return the Ethernet Configuration, contained in {@link IpConfiguration}.
+     */
+    @Override
+    public IpConfiguration getConfiguration(String iface) {
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        if (mTracker.isRestrictedInterface(iface)) {
+            PermissionUtils.enforceRestrictedNetworkPermission(mContext, TAG);
+        }
+
+        return new IpConfiguration(mTracker.getIpConfiguration(iface));
+    }
+
+    /**
+     * Set Ethernet configuration
+     */
+    @Override
+    public void setConfiguration(String iface, IpConfiguration config) {
+        throwIfEthernetNotStarted();
+
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+        if (mTracker.isRestrictedInterface(iface)) {
+            PermissionUtils.enforceRestrictedNetworkPermission(mContext, TAG);
+        }
+
+        // TODO: this does not check proxy settings, gateways, etc.
+        // Fix this by making IpConfiguration a complete representation of static configuration.
+        mTracker.updateIpConfiguration(iface, new IpConfiguration(config));
+    }
+
+    /**
+     * Indicates whether given interface is available.
+     */
+    @Override
+    public boolean isAvailable(String iface) {
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        if (mTracker.isRestrictedInterface(iface)) {
+            PermissionUtils.enforceRestrictedNetworkPermission(mContext, TAG);
+        }
+
+        return mTracker.isTrackingInterface(iface);
+    }
+
+    /**
+     * Adds a listener.
+     * @param listener A {@link IEthernetServiceListener} to add.
+     */
+    public void addListener(IEthernetServiceListener listener) throws RemoteException {
+        Objects.requireNonNull(listener, "listener must not be null");
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        mTracker.addListener(listener, checkUseRestrictedNetworksPermission());
+    }
+
+    /**
+     * Removes a listener.
+     * @param listener A {@link IEthernetServiceListener} to remove.
+     */
+    public void removeListener(IEthernetServiceListener listener) {
+        if (listener == null) {
+            throw new IllegalArgumentException("listener must not be null");
+        }
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        mTracker.removeListener(listener);
+    }
+
+    @Override
+    public void setIncludeTestInterfaces(boolean include) {
+        PermissionUtils.enforceNetworkStackPermissionOr(mContext,
+                android.Manifest.permission.NETWORK_SETTINGS);
+        mTracker.setIncludeTestInterfaces(include);
+    }
+
+    @Override
+    public void requestTetheredInterface(ITetheredInterfaceCallback callback) {
+        Objects.requireNonNull(callback, "callback must not be null");
+        PermissionUtils.enforceNetworkStackPermissionOr(mContext,
+                android.Manifest.permission.NETWORK_SETTINGS);
+        mTracker.requestTetheredInterface(callback);
+    }
+
+    @Override
+    public void releaseTetheredInterface(ITetheredInterfaceCallback callback) {
+        Objects.requireNonNull(callback, "callback must not be null");
+        PermissionUtils.enforceNetworkStackPermissionOr(mContext,
+                android.Manifest.permission.NETWORK_SETTINGS);
+        mTracker.releaseTetheredInterface(callback);
+    }
+
+    @Override
+    protected void dump(FileDescriptor fd, PrintWriter writer, String[] args) {
+        final IndentingPrintWriter pw = new IndentingPrintWriter(writer, "  ");
+        if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.DUMP)
+                != PackageManager.PERMISSION_GRANTED) {
+            pw.println("Permission Denial: can't dump EthernetService from pid="
+                    + Binder.getCallingPid()
+                    + ", uid=" + Binder.getCallingUid());
+            return;
+        }
+
+        pw.println("Current Ethernet state: ");
+        pw.increaseIndent();
+        mTracker.dump(fd, pw, args);
+        pw.decreaseIndent();
+
+        pw.println("Handler:");
+        pw.increaseIndent();
+        mHandler.dump(new PrintWriterPrinter(pw), "EthernetServiceImpl");
+        pw.decreaseIndent();
+    }
+
+    private void enforceNetworkManagementPermission() {
+        mContext.enforceCallingOrSelfPermission(
+                android.Manifest.permission.MANAGE_ETHERNET_NETWORKS,
+                "EthernetServiceImpl");
+    }
+
+    private void enforceManageTestNetworksPermission() {
+        mContext.enforceCallingOrSelfPermission(
+                android.Manifest.permission.MANAGE_TEST_NETWORKS,
+                "EthernetServiceImpl");
+    }
+
+    private void maybeValidateTestCapabilities(final String iface,
+            @Nullable final NetworkCapabilities nc) {
+        if (!mTracker.isValidTestInterface(iface)) {
+            return;
+        }
+        // For test interfaces, only null or capabilities that include TRANSPORT_TEST are
+        // allowed.
+        if (nc != null && !nc.hasTransport(TRANSPORT_TEST)) {
+            throw new IllegalArgumentException(
+                    "Updates to test interfaces must have NetworkCapabilities.TRANSPORT_TEST.");
+        }
+    }
+
+    private void enforceAdminPermission(final String iface, boolean enforceAutomotive,
+            final String logMessage) {
+        if (mTracker.isValidTestInterface(iface)) {
+            enforceManageTestNetworksPermission();
+        } else {
+            enforceNetworkManagementPermission();
+            if (enforceAutomotive) {
+                enforceAutomotiveDevice(logMessage);
+            }
+        }
+    }
+
+    @Override
+    public void updateConfiguration(@NonNull final String iface,
+            @NonNull final EthernetNetworkUpdateRequest request,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        Objects.requireNonNull(iface);
+        Objects.requireNonNull(request);
+        throwIfEthernetNotStarted();
+
+        // TODO: validate that iface is listed in overlay config_ethernet_interfaces
+        // only automotive devices are allowed to set the NetworkCapabilities using this API
+        enforceAdminPermission(iface, request.getNetworkCapabilities() != null,
+                "updateConfiguration() with non-null capabilities");
+        maybeValidateTestCapabilities(iface, request.getNetworkCapabilities());
+
+        mTracker.updateConfiguration(
+                iface, request.getIpConfiguration(), request.getNetworkCapabilities(), listener);
+    }
+
+    @Override
+    public void connectNetwork(@NonNull final String iface,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        Log.i(TAG, "connectNetwork called with: iface=" + iface + ", listener=" + listener);
+        Objects.requireNonNull(iface);
+        throwIfEthernetNotStarted();
+
+        enforceAdminPermission(iface, true, "connectNetwork()");
+
+        mTracker.connectNetwork(iface, listener);
+    }
+
+    @Override
+    public void disconnectNetwork(@NonNull final String iface,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        Log.i(TAG, "disconnectNetwork called with: iface=" + iface + ", listener=" + listener);
+        Objects.requireNonNull(iface);
+        throwIfEthernetNotStarted();
+
+        enforceAdminPermission(iface, true, "connectNetwork()");
+
+        mTracker.disconnectNetwork(iface, listener);
+    }
+
+    @Override
+    public void setEthernetEnabled(boolean enabled) {
+        PermissionUtils.enforceNetworkStackPermissionOr(mContext,
+                android.Manifest.permission.NETWORK_SETTINGS);
+
+        mTracker.setEthernetEnabled(enabled);
+    }
+
+    @Override
+    public List<String> getInterfaceList() {
+        PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
+        return mTracker.getInterfaceList();
+    }
+}
diff --git a/service-t/src/com/android/server/ethernet/EthernetTracker.java b/service-t/src/com/android/server/ethernet/EthernetTracker.java
new file mode 100644
index 0000000..c291b3f
--- /dev/null
+++ b/service-t/src/com/android/server/ethernet/EthernetTracker.java
@@ -0,0 +1,942 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import static android.net.EthernetManager.ETHERNET_STATE_DISABLED;
+import static android.net.EthernetManager.ETHERNET_STATE_ENABLED;
+import static android.net.TestNetworkManager.TEST_TAP_PREFIX;
+
+import static com.android.internal.annotations.VisibleForTesting.Visibility.PACKAGE;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.Context;
+import android.content.res.Resources;
+import android.net.ConnectivityResources;
+import android.net.EthernetManager;
+import android.net.IEthernetServiceListener;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.INetd;
+import android.net.ITetheredInterfaceCallback;
+import android.net.InterfaceConfigurationParcel;
+import android.net.IpConfiguration;
+import android.net.IpConfiguration.IpAssignment;
+import android.net.IpConfiguration.ProxySettings;
+import android.net.LinkAddress;
+import android.net.NetworkCapabilities;
+import android.net.StaticIpConfiguration;
+import android.os.ConditionVariable;
+import android.os.Handler;
+import android.os.RemoteCallbackList;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.text.TextUtils;
+import android.util.ArrayMap;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.IndentingPrintWriter;
+import com.android.net.module.util.BaseNetdUnsolicitedEventListener;
+import com.android.net.module.util.NetdUtils;
+import com.android.net.module.util.PermissionUtils;
+
+import java.io.FileDescriptor;
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Tracks Ethernet interfaces and manages interface configurations.
+ *
+ * <p>Interfaces may have different {@link android.net.NetworkCapabilities}. This mapping is defined
+ * in {@code config_ethernet_interfaces}. Notably, some interfaces could be marked as restricted by
+ * not specifying {@link android.net.NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED} flag.
+ * Interfaces could have associated {@link android.net.IpConfiguration}.
+ * Ethernet Interfaces may be present at boot time or appear after boot (e.g., for Ethernet adapters
+ * connected over USB). This class supports multiple interfaces. When an interface appears on the
+ * system (or is present at boot time) this class will start tracking it and bring it up. Only
+ * interfaces whose names match the {@code config_ethernet_iface_regex} regular expression are
+ * tracked.
+ *
+ * <p>All public or package private methods must be thread-safe unless stated otherwise.
+ */
+@VisibleForTesting(visibility = PACKAGE)
+public class EthernetTracker {
+    private static final int INTERFACE_MODE_CLIENT = 1;
+    private static final int INTERFACE_MODE_SERVER = 2;
+
+    private static final String TAG = EthernetTracker.class.getSimpleName();
+    private static final boolean DBG = EthernetNetworkFactory.DBG;
+
+    private static final String TEST_IFACE_REGEXP = TEST_TAP_PREFIX + "\\d+";
+    private static final String LEGACY_IFACE_REGEXP = "eth\\d";
+
+    /**
+     * Interface names we track. This is a product-dependent regular expression, plus,
+     * if setIncludeTestInterfaces is true, any test interfaces.
+     */
+    private volatile String mIfaceMatch;
+    /**
+     * Track test interfaces if true, don't track otherwise.
+     */
+    private boolean mIncludeTestInterfaces = false;
+
+    /** Mapping between {iface name | mac address} -> {NetworkCapabilities} */
+    private final ConcurrentHashMap<String, NetworkCapabilities> mNetworkCapabilities =
+            new ConcurrentHashMap<>();
+    private final ConcurrentHashMap<String, IpConfiguration> mIpConfigurations =
+            new ConcurrentHashMap<>();
+
+    private final Context mContext;
+    private final INetd mNetd;
+    private final Handler mHandler;
+    private final EthernetNetworkFactory mFactory;
+    private final EthernetConfigStore mConfigStore;
+    private final Dependencies mDeps;
+
+    private final RemoteCallbackList<IEthernetServiceListener> mListeners =
+            new RemoteCallbackList<>();
+    private final TetheredInterfaceRequestList mTetheredInterfaceRequests =
+            new TetheredInterfaceRequestList();
+
+    // Used only on the handler thread
+    private String mDefaultInterface;
+    private int mDefaultInterfaceMode = INTERFACE_MODE_CLIENT;
+    // Tracks whether clients were notified that the tethered interface is available
+    private boolean mTetheredInterfaceWasAvailable = false;
+    private volatile IpConfiguration mIpConfigForDefaultInterface;
+
+    private int mEthernetState = ETHERNET_STATE_ENABLED;
+
+    private class TetheredInterfaceRequestList extends
+            RemoteCallbackList<ITetheredInterfaceCallback> {
+        @Override
+        public void onCallbackDied(ITetheredInterfaceCallback cb, Object cookie) {
+            mHandler.post(EthernetTracker.this::maybeUntetherDefaultInterface);
+        }
+    }
+
+    public static class Dependencies {
+        // TODO: remove legacy resource fallback after migrating its overlays.
+        private String getPlatformRegexResource(Context context) {
+            final Resources r = context.getResources();
+            final int resId =
+                r.getIdentifier("config_ethernet_iface_regex", "string", context.getPackageName());
+            return r.getString(resId);
+        }
+
+        // TODO: remove legacy resource fallback after migrating its overlays.
+        private String[] getPlatformInterfaceConfigs(Context context) {
+            final Resources r = context.getResources();
+            final int resId = r.getIdentifier("config_ethernet_interfaces", "array",
+                    context.getPackageName());
+            return r.getStringArray(resId);
+        }
+
+        public String getInterfaceRegexFromResource(Context context) {
+            final String platformRegex = getPlatformRegexResource(context);
+            final String match;
+            if (!LEGACY_IFACE_REGEXP.equals(platformRegex)) {
+                // Platform resource is not the historical default: use the overlay
+                match = platformRegex;
+            } else {
+                final ConnectivityResources resources = new ConnectivityResources(context);
+                match = resources.get().getString(
+                        com.android.connectivity.resources.R.string.config_ethernet_iface_regex);
+            }
+            return match;
+        }
+
+        public String[] getInterfaceConfigFromResource(Context context) {
+            final String[] platformInterfaceConfigs = getPlatformInterfaceConfigs(context);
+            final String[] interfaceConfigs;
+            if (platformInterfaceConfigs.length != 0) {
+                // Platform resource is not the historical default: use the overlay
+                interfaceConfigs = platformInterfaceConfigs;
+            } else {
+                final ConnectivityResources resources = new ConnectivityResources(context);
+                interfaceConfigs = resources.get().getStringArray(
+                        com.android.connectivity.resources.R.array.config_ethernet_interfaces);
+            }
+            return interfaceConfigs;
+        }
+    }
+
+    EthernetTracker(@NonNull final Context context, @NonNull final Handler handler,
+            @NonNull final EthernetNetworkFactory factory, @NonNull final INetd netd) {
+        this(context, handler, factory, netd, new Dependencies());
+    }
+
+    @VisibleForTesting
+    EthernetTracker(@NonNull final Context context, @NonNull final Handler handler,
+            @NonNull final EthernetNetworkFactory factory, @NonNull final INetd netd,
+            @NonNull final Dependencies deps) {
+        mContext = context;
+        mHandler = handler;
+        mFactory = factory;
+        mNetd = netd;
+        mDeps = deps;
+
+        // Interface match regex.
+        updateIfaceMatchRegexp();
+
+        // Read default Ethernet interface configuration from resources
+        final String[] interfaceConfigs = mDeps.getInterfaceConfigFromResource(context);
+        for (String strConfig : interfaceConfigs) {
+            parseEthernetConfig(strConfig);
+        }
+
+        mConfigStore = new EthernetConfigStore();
+    }
+
+    void start() {
+        mFactory.register();
+        mConfigStore.read();
+
+        // Default interface is just the first one we want to track.
+        mIpConfigForDefaultInterface = mConfigStore.getIpConfigurationForDefaultInterface();
+        final ArrayMap<String, IpConfiguration> configs = mConfigStore.getIpConfigurations();
+        for (int i = 0; i < configs.size(); i++) {
+            mIpConfigurations.put(configs.keyAt(i), configs.valueAt(i));
+        }
+
+        try {
+            PermissionUtils.enforceNetworkStackPermission(mContext);
+            mNetd.registerUnsolicitedEventListener(new InterfaceObserver());
+        } catch (RemoteException | ServiceSpecificException e) {
+            Log.e(TAG, "Could not register InterfaceObserver " + e);
+        }
+
+        mHandler.post(this::trackAvailableInterfaces);
+    }
+
+    void updateIpConfiguration(String iface, IpConfiguration ipConfiguration) {
+        if (DBG) {
+            Log.i(TAG, "updateIpConfiguration, iface: " + iface + ", cfg: " + ipConfiguration);
+        }
+        writeIpConfiguration(iface, ipConfiguration);
+        mHandler.post(() -> {
+            mFactory.updateInterface(iface, ipConfiguration, null, null);
+            broadcastInterfaceStateChange(iface);
+        });
+    }
+
+    private void writeIpConfiguration(@NonNull final String iface,
+            @NonNull final IpConfiguration ipConfig) {
+        mConfigStore.write(iface, ipConfig);
+        mIpConfigurations.put(iface, ipConfig);
+    }
+
+    private IpConfiguration getIpConfigurationForCallback(String iface, int state) {
+        return (state == EthernetManager.STATE_ABSENT) ? null : getOrCreateIpConfiguration(iface);
+    }
+
+    private void ensureRunningOnEthernetServiceThread() {
+        if (mHandler.getLooper().getThread() != Thread.currentThread()) {
+            throw new IllegalStateException(
+                    "Not running on EthernetService thread: "
+                            + Thread.currentThread().getName());
+        }
+    }
+
+    /**
+     * Broadcast the link state or IpConfiguration change of existing Ethernet interfaces to all
+     * listeners.
+     */
+    protected void broadcastInterfaceStateChange(@NonNull String iface) {
+        ensureRunningOnEthernetServiceThread();
+        final int state = mFactory.getInterfaceState(iface);
+        final int role = getInterfaceRole(iface);
+        final IpConfiguration config = getIpConfigurationForCallback(iface, state);
+        final int n = mListeners.beginBroadcast();
+        for (int i = 0; i < n; i++) {
+            try {
+                mListeners.getBroadcastItem(i).onInterfaceStateChanged(iface, state, role, config);
+            } catch (RemoteException e) {
+                // Do nothing here.
+            }
+        }
+        mListeners.finishBroadcast();
+    }
+
+    /**
+     * Unicast the interface state or IpConfiguration change of existing Ethernet interfaces to a
+     * specific listener.
+     */
+    protected void unicastInterfaceStateChange(@NonNull IEthernetServiceListener listener,
+            @NonNull String iface) {
+        ensureRunningOnEthernetServiceThread();
+        final int state = mFactory.getInterfaceState(iface);
+        final int role = getInterfaceRole(iface);
+        final IpConfiguration config = getIpConfigurationForCallback(iface, state);
+        try {
+            listener.onInterfaceStateChanged(iface, state, role, config);
+        } catch (RemoteException e) {
+            // Do nothing here.
+        }
+    }
+
+    @VisibleForTesting(visibility = PACKAGE)
+    protected void updateConfiguration(@NonNull final String iface,
+            @Nullable final IpConfiguration ipConfig,
+            @Nullable final NetworkCapabilities capabilities,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        if (DBG) {
+            Log.i(TAG, "updateConfiguration, iface: " + iface + ", capabilities: " + capabilities
+                    + ", ipConfig: " + ipConfig);
+        }
+
+        final IpConfiguration localIpConfig = ipConfig == null
+                ? null : new IpConfiguration(ipConfig);
+        if (ipConfig != null) {
+            writeIpConfiguration(iface, localIpConfig);
+        }
+
+        if (null != capabilities) {
+            mNetworkCapabilities.put(iface, capabilities);
+        }
+        mHandler.post(() -> {
+            mFactory.updateInterface(iface, localIpConfig, capabilities, listener);
+            broadcastInterfaceStateChange(iface);
+        });
+    }
+
+    @VisibleForTesting(visibility = PACKAGE)
+    protected void connectNetwork(@NonNull final String iface,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        mHandler.post(() -> updateInterfaceState(iface, true, listener));
+    }
+
+    @VisibleForTesting(visibility = PACKAGE)
+    protected void disconnectNetwork(@NonNull final String iface,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        mHandler.post(() -> updateInterfaceState(iface, false, listener));
+    }
+
+    IpConfiguration getIpConfiguration(String iface) {
+        return mIpConfigurations.get(iface);
+    }
+
+    @VisibleForTesting(visibility = PACKAGE)
+    protected boolean isTrackingInterface(String iface) {
+        return mFactory.hasInterface(iface);
+    }
+
+    String[] getInterfaces(boolean includeRestricted) {
+        return mFactory.getAvailableInterfaces(includeRestricted);
+    }
+
+    List<String> getInterfaceList() {
+        final List<String> interfaceList = new ArrayList<String>();
+        final String[] ifaces;
+        try {
+            ifaces = mNetd.interfaceGetList();
+        } catch (RemoteException e) {
+            Log.e(TAG, "Could not get list of interfaces " + e);
+            return interfaceList;
+        }
+        final String ifaceMatch = mIfaceMatch;
+        for (String iface : ifaces) {
+            if (iface.matches(ifaceMatch)) interfaceList.add(iface);
+        }
+        return interfaceList;
+    }
+
+    /**
+     * Returns true if given interface was configured as restricted (doesn't have
+     * NET_CAPABILITY_NOT_RESTRICTED) capability. Otherwise, returns false.
+     */
+    boolean isRestrictedInterface(String iface) {
+        final NetworkCapabilities nc = mNetworkCapabilities.get(iface);
+        return nc != null && !nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
+    }
+
+    void addListener(IEthernetServiceListener listener, boolean canUseRestrictedNetworks) {
+        mHandler.post(() -> {
+            if (!mListeners.register(listener, new ListenerInfo(canUseRestrictedNetworks))) {
+                // Remote process has already died
+                return;
+            }
+            for (String iface : getInterfaces(canUseRestrictedNetworks)) {
+                unicastInterfaceStateChange(listener, iface);
+            }
+
+            unicastEthernetStateChange(listener, mEthernetState);
+        });
+    }
+
+    void removeListener(IEthernetServiceListener listener) {
+        mHandler.post(() -> mListeners.unregister(listener));
+    }
+
+    public void setIncludeTestInterfaces(boolean include) {
+        mHandler.post(() -> {
+            mIncludeTestInterfaces = include;
+            updateIfaceMatchRegexp();
+            mHandler.post(() -> trackAvailableInterfaces());
+        });
+    }
+
+    public void requestTetheredInterface(ITetheredInterfaceCallback callback) {
+        mHandler.post(() -> {
+            if (!mTetheredInterfaceRequests.register(callback)) {
+                // Remote process has already died
+                return;
+            }
+            if (mDefaultInterfaceMode == INTERFACE_MODE_SERVER) {
+                if (mTetheredInterfaceWasAvailable) {
+                    notifyTetheredInterfaceAvailable(callback, mDefaultInterface);
+                }
+                return;
+            }
+
+            setDefaultInterfaceMode(INTERFACE_MODE_SERVER);
+        });
+    }
+
+    public void releaseTetheredInterface(ITetheredInterfaceCallback callback) {
+        mHandler.post(() -> {
+            mTetheredInterfaceRequests.unregister(callback);
+            maybeUntetherDefaultInterface();
+        });
+    }
+
+    private void notifyTetheredInterfaceAvailable(ITetheredInterfaceCallback cb, String iface) {
+        try {
+            cb.onAvailable(iface);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error sending tethered interface available callback", e);
+        }
+    }
+
+    private void notifyTetheredInterfaceUnavailable(ITetheredInterfaceCallback cb) {
+        try {
+            cb.onUnavailable();
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error sending tethered interface available callback", e);
+        }
+    }
+
+    private void maybeUntetherDefaultInterface() {
+        if (mTetheredInterfaceRequests.getRegisteredCallbackCount() > 0) return;
+        if (mDefaultInterfaceMode == INTERFACE_MODE_CLIENT) return;
+        setDefaultInterfaceMode(INTERFACE_MODE_CLIENT);
+    }
+
+    private void setDefaultInterfaceMode(int mode) {
+        Log.d(TAG, "Setting default interface mode to " + mode);
+        mDefaultInterfaceMode = mode;
+        if (mDefaultInterface != null) {
+            removeInterface(mDefaultInterface);
+            addInterface(mDefaultInterface);
+        }
+    }
+
+    private int getInterfaceRole(final String iface) {
+        if (!mFactory.hasInterface(iface)) return EthernetManager.ROLE_NONE;
+        final int mode = getInterfaceMode(iface);
+        return (mode == INTERFACE_MODE_CLIENT)
+                ? EthernetManager.ROLE_CLIENT
+                : EthernetManager.ROLE_SERVER;
+    }
+
+    private int getInterfaceMode(final String iface) {
+        if (iface.equals(mDefaultInterface)) {
+            return mDefaultInterfaceMode;
+        }
+        return INTERFACE_MODE_CLIENT;
+    }
+
+    private void removeInterface(String iface) {
+        mFactory.removeInterface(iface);
+        maybeUpdateServerModeInterfaceState(iface, false);
+    }
+
+    private void stopTrackingInterface(String iface) {
+        removeInterface(iface);
+        if (iface.equals(mDefaultInterface)) {
+            mDefaultInterface = null;
+        }
+        broadcastInterfaceStateChange(iface);
+    }
+
+    private void addInterface(String iface) {
+        InterfaceConfigurationParcel config = null;
+        // Bring up the interface so we get link status indications.
+        try {
+            PermissionUtils.enforceNetworkStackPermission(mContext);
+            NetdUtils.setInterfaceUp(mNetd, iface);
+            config = NetdUtils.getInterfaceConfigParcel(mNetd, iface);
+        } catch (IllegalStateException e) {
+            // Either the system is crashing or the interface has disappeared. Just ignore the
+            // error; we haven't modified any state because we only do that if our calls succeed.
+            Log.e(TAG, "Error upping interface " + iface, e);
+        }
+
+        if (config == null) {
+            Log.e(TAG, "Null interface config parcelable for " + iface + ". Bailing out.");
+            return;
+        }
+
+        final String hwAddress = config.hwAddr;
+
+        NetworkCapabilities nc = mNetworkCapabilities.get(iface);
+        if (nc == null) {
+            // Try to resolve using mac address
+            nc = mNetworkCapabilities.get(hwAddress);
+            if (nc == null) {
+                final boolean isTestIface = iface.matches(TEST_IFACE_REGEXP);
+                nc = createDefaultNetworkCapabilities(isTestIface);
+            }
+        }
+
+        final int mode = getInterfaceMode(iface);
+        if (mode == INTERFACE_MODE_CLIENT) {
+            IpConfiguration ipConfiguration = getOrCreateIpConfiguration(iface);
+            Log.d(TAG, "Tracking interface in client mode: " + iface);
+            mFactory.addInterface(iface, hwAddress, ipConfiguration, nc);
+        } else {
+            maybeUpdateServerModeInterfaceState(iface, true);
+        }
+
+        // Note: if the interface already has link (e.g., if we crashed and got
+        // restarted while it was running), we need to fake a link up notification so we
+        // start configuring it.
+        if (NetdUtils.hasFlag(config, "running")) {
+            updateInterfaceState(iface, true);
+        }
+    }
+
+    private void updateInterfaceState(String iface, boolean up) {
+        updateInterfaceState(iface, up, null /* listener */);
+    }
+
+    private void updateInterfaceState(@NonNull final String iface, final boolean up,
+            @Nullable final INetworkInterfaceOutcomeReceiver listener) {
+        final int mode = getInterfaceMode(iface);
+        final boolean factoryLinkStateUpdated = (mode == INTERFACE_MODE_CLIENT)
+                && mFactory.updateInterfaceLinkState(iface, up, listener);
+
+        if (factoryLinkStateUpdated) {
+            broadcastInterfaceStateChange(iface);
+        }
+    }
+
+    private void maybeUpdateServerModeInterfaceState(String iface, boolean available) {
+        if (available == mTetheredInterfaceWasAvailable || !iface.equals(mDefaultInterface)) return;
+
+        Log.d(TAG, (available ? "Tracking" : "No longer tracking")
+                + " interface in server mode: " + iface);
+
+        final int pendingCbs = mTetheredInterfaceRequests.beginBroadcast();
+        for (int i = 0; i < pendingCbs; i++) {
+            ITetheredInterfaceCallback item = mTetheredInterfaceRequests.getBroadcastItem(i);
+            if (available) {
+                notifyTetheredInterfaceAvailable(item, iface);
+            } else {
+                notifyTetheredInterfaceUnavailable(item);
+            }
+        }
+        mTetheredInterfaceRequests.finishBroadcast();
+        mTetheredInterfaceWasAvailable = available;
+    }
+
+    private void maybeTrackInterface(String iface) {
+        if (!iface.matches(mIfaceMatch)) {
+            return;
+        }
+
+        // If we don't already track this interface, and if this interface matches
+        // our regex, start tracking it.
+        if (mFactory.hasInterface(iface) || iface.equals(mDefaultInterface)) {
+            if (DBG) Log.w(TAG, "Ignoring already-tracked interface " + iface);
+            return;
+        }
+        if (DBG) Log.i(TAG, "maybeTrackInterface: " + iface);
+
+        // TODO: avoid making an interface default if it has configured NetworkCapabilities.
+        if (mDefaultInterface == null) {
+            mDefaultInterface = iface;
+        }
+
+        if (mIpConfigForDefaultInterface != null) {
+            updateIpConfiguration(iface, mIpConfigForDefaultInterface);
+            mIpConfigForDefaultInterface = null;
+        }
+
+        addInterface(iface);
+
+        broadcastInterfaceStateChange(iface);
+    }
+
+    private void trackAvailableInterfaces() {
+        try {
+            final String[] ifaces = mNetd.interfaceGetList();
+            for (String iface : ifaces) {
+                maybeTrackInterface(iface);
+            }
+        } catch (RemoteException | ServiceSpecificException e) {
+            Log.e(TAG, "Could not get list of interfaces " + e);
+        }
+    }
+
+    private class InterfaceObserver extends BaseNetdUnsolicitedEventListener {
+
+        @Override
+        public void onInterfaceLinkStateChanged(String iface, boolean up) {
+            if (DBG) {
+                Log.i(TAG, "interfaceLinkStateChanged, iface: " + iface + ", up: " + up);
+            }
+            mHandler.post(() -> updateInterfaceState(iface, up));
+        }
+
+        @Override
+        public void onInterfaceAdded(String iface) {
+            if (DBG) {
+                Log.i(TAG, "onInterfaceAdded, iface: " + iface);
+            }
+            mHandler.post(() -> maybeTrackInterface(iface));
+        }
+
+        @Override
+        public void onInterfaceRemoved(String iface) {
+            if (DBG) {
+                Log.i(TAG, "onInterfaceRemoved, iface: " + iface);
+            }
+            mHandler.post(() -> stopTrackingInterface(iface));
+        }
+    }
+
+    private static class ListenerInfo {
+
+        boolean canUseRestrictedNetworks = false;
+
+        ListenerInfo(boolean canUseRestrictedNetworks) {
+            this.canUseRestrictedNetworks = canUseRestrictedNetworks;
+        }
+    }
+
+    /**
+     * Parses an Ethernet interface configuration
+     *
+     * @param configString represents an Ethernet configuration in the following format: {@code
+     * <interface name|mac address>;[Network Capabilities];[IP config];[Override Transport]}
+     */
+    private void parseEthernetConfig(String configString) {
+        final EthernetTrackerConfig config = createEthernetTrackerConfig(configString);
+        NetworkCapabilities nc = createNetworkCapabilities(
+                !TextUtils.isEmpty(config.mCapabilities)  /* clear default capabilities */,
+                config.mCapabilities, config.mTransport).build();
+        mNetworkCapabilities.put(config.mIface, nc);
+
+        if (null != config.mIpConfig) {
+            IpConfiguration ipConfig = parseStaticIpConfiguration(config.mIpConfig);
+            mIpConfigurations.put(config.mIface, ipConfig);
+        }
+    }
+
+    @VisibleForTesting
+    static EthernetTrackerConfig createEthernetTrackerConfig(@NonNull final String configString) {
+        Objects.requireNonNull(configString, "EthernetTrackerConfig requires non-null config");
+        return new EthernetTrackerConfig(configString.split(";", /* limit of tokens */ 4));
+    }
+
+    private static NetworkCapabilities createDefaultNetworkCapabilities(boolean isTestIface) {
+        NetworkCapabilities.Builder builder = createNetworkCapabilities(
+                false /* clear default capabilities */, null, null)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_SUSPENDED)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VCN_MANAGED);
+
+        if (isTestIface) {
+            builder.addTransportType(NetworkCapabilities.TRANSPORT_TEST);
+        } else {
+            builder.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+        }
+
+        return builder.build();
+    }
+
+    /**
+     * Parses a static list of network capabilities
+     *
+     * @param clearDefaultCapabilities Indicates whether or not to clear any default capabilities
+     * @param commaSeparatedCapabilities A comma separated string list of integer encoded
+     *                                   NetworkCapability.NET_CAPABILITY_* values
+     * @param overrideTransport A string representing a single integer encoded override transport
+     *                          type. Must be one of the NetworkCapability.TRANSPORT_*
+     *                          values. TRANSPORT_VPN is not supported. Errors with input
+     *                          will cause the override to be ignored.
+     */
+    @VisibleForTesting
+    static NetworkCapabilities.Builder createNetworkCapabilities(
+            boolean clearDefaultCapabilities, @Nullable String commaSeparatedCapabilities,
+            @Nullable String overrideTransport) {
+
+        final NetworkCapabilities.Builder builder = clearDefaultCapabilities
+                ? NetworkCapabilities.Builder.withoutDefaultCapabilities()
+                : new NetworkCapabilities.Builder();
+
+        // Determine the transport type. If someone has tried to define an override transport then
+        // attempt to add it. Since we can only have one override, all errors with it will
+        // gracefully default back to TRANSPORT_ETHERNET and warn the user. VPN is not allowed as an
+        // override type. Wifi Aware and LoWPAN are currently unsupported as well.
+        int transport = NetworkCapabilities.TRANSPORT_ETHERNET;
+        if (!TextUtils.isEmpty(overrideTransport)) {
+            try {
+                int parsedTransport = Integer.valueOf(overrideTransport);
+                if (parsedTransport == NetworkCapabilities.TRANSPORT_VPN
+                        || parsedTransport == NetworkCapabilities.TRANSPORT_WIFI_AWARE
+                        || parsedTransport == NetworkCapabilities.TRANSPORT_LOWPAN) {
+                    Log.e(TAG, "Override transport '" + parsedTransport + "' is not supported. "
+                            + "Defaulting to TRANSPORT_ETHERNET");
+                } else {
+                    transport = parsedTransport;
+                }
+            } catch (NumberFormatException nfe) {
+                Log.e(TAG, "Override transport type '" + overrideTransport + "' "
+                        + "could not be parsed. Defaulting to TRANSPORT_ETHERNET");
+            }
+        }
+
+        // Apply the transport. If the user supplied a valid number that is not a valid transport
+        // then adding will throw an exception. Default back to TRANSPORT_ETHERNET if that happens
+        try {
+            builder.addTransportType(transport);
+        } catch (IllegalArgumentException iae) {
+            Log.e(TAG, transport + " is not a valid NetworkCapability.TRANSPORT_* value. "
+                    + "Defaulting to TRANSPORT_ETHERNET");
+            builder.addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET);
+        }
+
+        builder.setLinkUpstreamBandwidthKbps(100 * 1000);
+        builder.setLinkDownstreamBandwidthKbps(100 * 1000);
+
+        if (!TextUtils.isEmpty(commaSeparatedCapabilities)) {
+            for (String strNetworkCapability : commaSeparatedCapabilities.split(",")) {
+                if (!TextUtils.isEmpty(strNetworkCapability)) {
+                    try {
+                        builder.addCapability(Integer.valueOf(strNetworkCapability));
+                    } catch (NumberFormatException nfe) {
+                        Log.e(TAG, "Capability '" + strNetworkCapability + "' could not be parsed");
+                    } catch (IllegalArgumentException iae) {
+                        Log.e(TAG, strNetworkCapability + " is not a valid "
+                                + "NetworkCapability.NET_CAPABILITY_* value");
+                    }
+                }
+            }
+        }
+        // Ethernet networks have no way to update the following capabilities, so they always
+        // have them.
+        builder.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING);
+        builder.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED);
+        builder.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_SUSPENDED);
+
+        return builder;
+    }
+
+    /**
+     * Parses static IP configuration.
+     *
+     * @param staticIpConfig represents static IP configuration in the following format: {@code
+     * ip=<ip-address/mask> gateway=<ip-address> dns=<comma-sep-ip-addresses>
+     *     domains=<comma-sep-domains>}
+     */
+    @VisibleForTesting
+    static IpConfiguration parseStaticIpConfiguration(String staticIpConfig) {
+        final StaticIpConfiguration.Builder staticIpConfigBuilder =
+                new StaticIpConfiguration.Builder();
+
+        for (String keyValueAsString : staticIpConfig.trim().split(" ")) {
+            if (TextUtils.isEmpty(keyValueAsString)) continue;
+
+            String[] pair = keyValueAsString.split("=");
+            if (pair.length != 2) {
+                throw new IllegalArgumentException("Unexpected token: " + keyValueAsString
+                        + " in " + staticIpConfig);
+            }
+
+            String key = pair[0];
+            String value = pair[1];
+
+            switch (key) {
+                case "ip":
+                    staticIpConfigBuilder.setIpAddress(new LinkAddress(value));
+                    break;
+                case "domains":
+                    staticIpConfigBuilder.setDomains(value);
+                    break;
+                case "gateway":
+                    staticIpConfigBuilder.setGateway(InetAddress.parseNumericAddress(value));
+                    break;
+                case "dns": {
+                    ArrayList<InetAddress> dnsAddresses = new ArrayList<>();
+                    for (String address: value.split(",")) {
+                        dnsAddresses.add(InetAddress.parseNumericAddress(address));
+                    }
+                    staticIpConfigBuilder.setDnsServers(dnsAddresses);
+                    break;
+                }
+                default : {
+                    throw new IllegalArgumentException("Unexpected key: " + key
+                            + " in " + staticIpConfig);
+                }
+            }
+        }
+        return createIpConfiguration(staticIpConfigBuilder.build());
+    }
+
+    private static IpConfiguration createIpConfiguration(
+            @NonNull final StaticIpConfiguration staticIpConfig) {
+        return new IpConfiguration.Builder().setStaticIpConfiguration(staticIpConfig).build();
+    }
+
+    private IpConfiguration getOrCreateIpConfiguration(String iface) {
+        IpConfiguration ret = mIpConfigurations.get(iface);
+        if (ret != null) return ret;
+        ret = new IpConfiguration();
+        ret.setIpAssignment(IpAssignment.DHCP);
+        ret.setProxySettings(ProxySettings.NONE);
+        return ret;
+    }
+
+    private void updateIfaceMatchRegexp() {
+        final String match = mDeps.getInterfaceRegexFromResource(mContext);
+        mIfaceMatch = mIncludeTestInterfaces
+                ? "(" + match + "|" + TEST_IFACE_REGEXP + ")"
+                : match;
+        Log.d(TAG, "Interface match regexp set to '" + mIfaceMatch + "'");
+    }
+
+    /**
+     * Validate if a given interface is valid for testing.
+     *
+     * @param iface the name of the interface to validate.
+     * @return {@code true} if test interfaces are enabled and the given {@code iface} has a test
+     * interface prefix, {@code false} otherwise.
+     */
+    public boolean isValidTestInterface(@NonNull final String iface) {
+        return mIncludeTestInterfaces && iface.matches(TEST_IFACE_REGEXP);
+    }
+
+    private void postAndWaitForRunnable(Runnable r) {
+        final ConditionVariable cv = new ConditionVariable();
+        if (mHandler.post(() -> {
+            r.run();
+            cv.open();
+        })) {
+            cv.block(2000L);
+        }
+    }
+
+    @VisibleForTesting(visibility = PACKAGE)
+    protected void setEthernetEnabled(boolean enabled) {
+        mHandler.post(() -> {
+            int newState = enabled ? ETHERNET_STATE_ENABLED : ETHERNET_STATE_DISABLED;
+            if (mEthernetState == newState) return;
+
+            mEthernetState = newState;
+
+            if (enabled) {
+                trackAvailableInterfaces();
+            } else {
+                // TODO: maybe also disable server mode interface as well.
+                untrackFactoryInterfaces();
+            }
+            broadcastEthernetStateChange(mEthernetState);
+        });
+    }
+
+    private void untrackFactoryInterfaces() {
+        for (String iface : mFactory.getAvailableInterfaces(true /* includeRestricted */)) {
+            stopTrackingInterface(iface);
+        }
+    }
+
+    private void unicastEthernetStateChange(@NonNull IEthernetServiceListener listener,
+            int state) {
+        ensureRunningOnEthernetServiceThread();
+        try {
+            listener.onEthernetStateChanged(state);
+        } catch (RemoteException e) {
+            // Do nothing here.
+        }
+    }
+
+    private void broadcastEthernetStateChange(int state) {
+        ensureRunningOnEthernetServiceThread();
+        final int n = mListeners.beginBroadcast();
+        for (int i = 0; i < n; i++) {
+            try {
+                mListeners.getBroadcastItem(i).onEthernetStateChanged(state);
+            } catch (RemoteException e) {
+                // Do nothing here.
+            }
+        }
+        mListeners.finishBroadcast();
+    }
+
+    void dump(FileDescriptor fd, IndentingPrintWriter pw, String[] args) {
+        postAndWaitForRunnable(() -> {
+            pw.println(getClass().getSimpleName());
+            pw.println("Ethernet interface name filter: " + mIfaceMatch);
+            pw.println("Default interface: " + mDefaultInterface);
+            pw.println("Default interface mode: " + mDefaultInterfaceMode);
+            pw.println("Tethered interface requests: "
+                    + mTetheredInterfaceRequests.getRegisteredCallbackCount());
+            pw.println("Listeners: " + mListeners.getRegisteredCallbackCount());
+            pw.println("IP Configurations:");
+            pw.increaseIndent();
+            for (String iface : mIpConfigurations.keySet()) {
+                pw.println(iface + ": " + mIpConfigurations.get(iface));
+            }
+            pw.decreaseIndent();
+            pw.println();
+
+            pw.println("Network Capabilities:");
+            pw.increaseIndent();
+            for (String iface : mNetworkCapabilities.keySet()) {
+                pw.println(iface + ": " + mNetworkCapabilities.get(iface));
+            }
+            pw.decreaseIndent();
+            pw.println();
+
+            mFactory.dump(fd, pw, args);
+        });
+    }
+
+    @VisibleForTesting
+    static class EthernetTrackerConfig {
+        final String mIface;
+        final String mCapabilities;
+        final String mIpConfig;
+        final String mTransport;
+
+        EthernetTrackerConfig(@NonNull final String[] tokens) {
+            Objects.requireNonNull(tokens, "EthernetTrackerConfig requires non-null tokens");
+            mIface = tokens[0];
+            mCapabilities = tokens.length > 1 ? tokens[1] : null;
+            mIpConfig = tokens.length > 2 && !TextUtils.isEmpty(tokens[2]) ? tokens[2] : null;
+            mTransport = tokens.length > 3 ? tokens[3] : null;
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/net/BpfInterfaceMapUpdater.java b/service-t/src/com/android/server/net/BpfInterfaceMapUpdater.java
new file mode 100644
index 0000000..25c88eb
--- /dev/null
+++ b/service-t/src/com/android/server/net/BpfInterfaceMapUpdater.java
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.server.net;
+
+import android.content.Context;
+import android.net.INetd;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.system.ErrnoException;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.BaseNetdUnsolicitedEventListener;
+import com.android.net.module.util.BpfMap;
+import com.android.net.module.util.IBpfMap;
+import com.android.net.module.util.InterfaceParams;
+import com.android.net.module.util.Struct.U32;
+
+/**
+ * Monitor interface added (without removed) and right interface name and its index to bpf map.
+ */
+public class BpfInterfaceMapUpdater {
+    private static final String TAG = BpfInterfaceMapUpdater.class.getSimpleName();
+    // This is current path but may be changed soon.
+    private static final String IFACE_INDEX_NAME_MAP_PATH =
+            "/sys/fs/bpf/map_netd_iface_index_name_map";
+    private final IBpfMap<U32, InterfaceMapValue> mBpfMap;
+    private final INetd mNetd;
+    private final Handler mHandler;
+    private final Dependencies mDeps;
+
+    public BpfInterfaceMapUpdater(Context ctx, Handler handler) {
+        this(ctx, handler, new Dependencies());
+    }
+
+    @VisibleForTesting
+    public BpfInterfaceMapUpdater(Context ctx, Handler handler, Dependencies deps) {
+        mDeps = deps;
+        mBpfMap = deps.getInterfaceMap();
+        mNetd = deps.getINetd(ctx);
+        mHandler = handler;
+    }
+
+    /**
+     * Dependencies of BpfInerfaceMapUpdater, for injection in tests.
+     */
+    @VisibleForTesting
+    public static class Dependencies {
+        /** Create BpfMap for updating interface and index mapping. */
+        public IBpfMap<U32, InterfaceMapValue> getInterfaceMap() {
+            try {
+                return new BpfMap<>(IFACE_INDEX_NAME_MAP_PATH, BpfMap.BPF_F_RDWR,
+                    U32.class, InterfaceMapValue.class);
+            } catch (ErrnoException e) {
+                Log.e(TAG, "Cannot create interface map: " + e);
+                return null;
+            }
+        }
+
+        /** Get InterfaceParams for giving interface name. */
+        public InterfaceParams getInterfaceParams(String ifaceName) {
+            return InterfaceParams.getByName(ifaceName);
+        }
+
+        /** Get INetd binder object. */
+        public INetd getINetd(Context ctx) {
+            return INetd.Stub.asInterface((IBinder) ctx.getSystemService(Context.NETD_SERVICE));
+        }
+    }
+
+    /**
+     * Start listening interface update event.
+     * Query current interface names before listening.
+     */
+    public void start() {
+        mHandler.post(() -> {
+            if (mBpfMap == null) {
+                Log.wtf(TAG, "Fail to start: Null bpf map");
+                return;
+            }
+
+            try {
+                // TODO: use a NetlinkMonitor and listen for RTM_NEWLINK messages instead.
+                mNetd.registerUnsolicitedEventListener(new InterfaceChangeObserver());
+            } catch (RemoteException e) {
+                Log.wtf(TAG, "Unable to register netd UnsolicitedEventListener, " + e);
+            }
+
+            final String[] ifaces;
+            try {
+                // TODO: use a netlink dump to get the current interface list.
+                ifaces = mNetd.interfaceGetList();
+            } catch (RemoteException | ServiceSpecificException e) {
+                Log.wtf(TAG, "Unable to query interface names by netd, " + e);
+                return;
+            }
+
+            for (String ifaceName : ifaces) {
+                addInterface(ifaceName);
+            }
+        });
+    }
+
+    private void addInterface(String ifaceName) {
+        final InterfaceParams iface = mDeps.getInterfaceParams(ifaceName);
+        if (iface == null) {
+            Log.e(TAG, "Unable to get InterfaceParams for " + ifaceName);
+            return;
+        }
+
+        try {
+            mBpfMap.updateEntry(new U32(iface.index), new InterfaceMapValue(ifaceName));
+        } catch (ErrnoException e) {
+            Log.e(TAG, "Unable to update entry for " + ifaceName + ", " + e);
+        }
+    }
+
+    private class InterfaceChangeObserver extends BaseNetdUnsolicitedEventListener {
+        @Override
+        public void onInterfaceAdded(String ifName) {
+            mHandler.post(() -> addInterface(ifName));
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/net/CookieTagMapKey.java b/service-t/src/com/android/server/net/CookieTagMapKey.java
new file mode 100644
index 0000000..443e5b3
--- /dev/null
+++ b/service-t/src/com/android/server/net/CookieTagMapKey.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * Key for cookie tag map.
+ */
+public class CookieTagMapKey extends Struct {
+    @Field(order = 0, type = Type.S64)
+    public final long socketCookie;
+
+    public CookieTagMapKey(final long socketCookie) {
+        this.socketCookie = socketCookie;
+    }
+}
diff --git a/service-t/src/com/android/server/net/CookieTagMapValue.java b/service-t/src/com/android/server/net/CookieTagMapValue.java
new file mode 100644
index 0000000..93b9195
--- /dev/null
+++ b/service-t/src/com/android/server/net/CookieTagMapValue.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * Value for cookie tag map.
+ */
+public class CookieTagMapValue extends Struct {
+    @Field(order = 0, type = Type.U32)
+    public final long uid;
+
+    @Field(order = 1, type = Type.U32)
+    public final long tag;
+
+    public CookieTagMapValue(final long uid, final long tag) {
+        this.uid = uid;
+        this.tag = tag;
+    }
+}
diff --git a/service-t/src/com/android/server/net/InterfaceMapValue.java b/service-t/src/com/android/server/net/InterfaceMapValue.java
new file mode 100644
index 0000000..42c0044
--- /dev/null
+++ b/service-t/src/com/android/server/net/InterfaceMapValue.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * The value of bpf interface index map which is used for NetworkStatsService.
+ */
+public class InterfaceMapValue extends Struct {
+    @Field(order = 0, type = Type.ByteArray, arraysize = 16)
+    public final byte[] interfaceName;
+
+    public InterfaceMapValue(String iface) {
+        final byte[] ifaceArray = iface.getBytes();
+        interfaceName = new byte[16];
+        // All array bytes after the interface name, if any, must be 0.
+        System.arraycopy(ifaceArray, 0, interfaceName, 0, ifaceArray.length);
+    }
+}
diff --git a/service-t/src/com/android/server/net/IpConfigStore.java b/service-t/src/com/android/server/net/IpConfigStore.java
new file mode 100644
index 0000000..3a9a544
--- /dev/null
+++ b/service-t/src/com/android/server/net/IpConfigStore.java
@@ -0,0 +1,449 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import android.net.InetAddresses;
+import android.net.IpConfiguration;
+import android.net.IpConfiguration.IpAssignment;
+import android.net.IpConfiguration.ProxySettings;
+import android.net.LinkAddress;
+import android.net.ProxyInfo;
+import android.net.StaticIpConfiguration;
+import android.net.Uri;
+import android.util.ArrayMap;
+import android.util.Log;
+import android.util.SparseArray;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.ProxyUtils;
+
+import java.io.BufferedInputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.EOFException;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * This class provides an API to store and manage L3 network IP configuration.
+ */
+public class IpConfigStore {
+    private static final String TAG = "IpConfigStore";
+    private static final boolean DBG = false;
+
+    protected final DelayedDiskWrite mWriter;
+
+    /* IP and proxy configuration keys */
+    protected static final String ID_KEY = "id";
+    protected static final String IP_ASSIGNMENT_KEY = "ipAssignment";
+    protected static final String LINK_ADDRESS_KEY = "linkAddress";
+    protected static final String GATEWAY_KEY = "gateway";
+    protected static final String DNS_KEY = "dns";
+    protected static final String PROXY_SETTINGS_KEY = "proxySettings";
+    protected static final String PROXY_HOST_KEY = "proxyHost";
+    protected static final String PROXY_PORT_KEY = "proxyPort";
+    protected static final String PROXY_PAC_FILE = "proxyPac";
+    protected static final String EXCLUSION_LIST_KEY = "exclusionList";
+    protected static final String EOS = "eos";
+
+    protected static final int IPCONFIG_FILE_VERSION = 3;
+
+    public IpConfigStore(DelayedDiskWrite writer) {
+        mWriter = writer;
+    }
+
+    public IpConfigStore() {
+        this(new DelayedDiskWrite());
+    }
+
+    private static boolean writeConfig(DataOutputStream out, String configKey,
+            IpConfiguration config) throws IOException {
+        return writeConfig(out, configKey, config, IPCONFIG_FILE_VERSION);
+    }
+
+    /**
+     *  Write the IP configuration with the given parameters to {@link DataOutputStream}.
+     */
+    @VisibleForTesting
+    public static boolean writeConfig(DataOutputStream out, String configKey,
+                                IpConfiguration config, int version) throws IOException {
+        boolean written = false;
+
+        try {
+            switch (config.getIpAssignment()) {
+                case STATIC:
+                    out.writeUTF(IP_ASSIGNMENT_KEY);
+                    out.writeUTF(config.getIpAssignment().toString());
+                    StaticIpConfiguration staticIpConfiguration = config.getStaticIpConfiguration();
+                    if (staticIpConfiguration != null) {
+                        if (staticIpConfiguration.getIpAddress() != null) {
+                            LinkAddress ipAddress = staticIpConfiguration.getIpAddress();
+                            out.writeUTF(LINK_ADDRESS_KEY);
+                            out.writeUTF(ipAddress.getAddress().getHostAddress());
+                            out.writeInt(ipAddress.getPrefixLength());
+                        }
+                        if (staticIpConfiguration.getGateway() != null) {
+                            out.writeUTF(GATEWAY_KEY);
+                            out.writeInt(0);  // Default route.
+                            out.writeInt(1);  // Have a gateway.
+                            out.writeUTF(staticIpConfiguration.getGateway().getHostAddress());
+                        }
+                        for (InetAddress inetAddr : staticIpConfiguration.getDnsServers()) {
+                            out.writeUTF(DNS_KEY);
+                            out.writeUTF(inetAddr.getHostAddress());
+                        }
+                    }
+                    written = true;
+                    break;
+                case DHCP:
+                    out.writeUTF(IP_ASSIGNMENT_KEY);
+                    out.writeUTF(config.getIpAssignment().toString());
+                    written = true;
+                    break;
+                case UNASSIGNED:
+                /* Ignore */
+                    break;
+                default:
+                    loge("Ignore invalid ip assignment while writing");
+                    break;
+            }
+
+            switch (config.getProxySettings()) {
+                case STATIC:
+                    ProxyInfo proxyProperties = config.getHttpProxy();
+                    String exclusionList = ProxyUtils.exclusionListAsString(
+                            proxyProperties.getExclusionList());
+                    out.writeUTF(PROXY_SETTINGS_KEY);
+                    out.writeUTF(config.getProxySettings().toString());
+                    out.writeUTF(PROXY_HOST_KEY);
+                    out.writeUTF(proxyProperties.getHost());
+                    out.writeUTF(PROXY_PORT_KEY);
+                    out.writeInt(proxyProperties.getPort());
+                    if (exclusionList != null) {
+                        out.writeUTF(EXCLUSION_LIST_KEY);
+                        out.writeUTF(exclusionList);
+                    }
+                    written = true;
+                    break;
+                case PAC:
+                    ProxyInfo proxyPacProperties = config.getHttpProxy();
+                    out.writeUTF(PROXY_SETTINGS_KEY);
+                    out.writeUTF(config.getProxySettings().toString());
+                    out.writeUTF(PROXY_PAC_FILE);
+                    out.writeUTF(proxyPacProperties.getPacFileUrl().toString());
+                    written = true;
+                    break;
+                case NONE:
+                    out.writeUTF(PROXY_SETTINGS_KEY);
+                    out.writeUTF(config.getProxySettings().toString());
+                    written = true;
+                    break;
+                case UNASSIGNED:
+                    /* Ignore */
+                    break;
+                default:
+                    loge("Ignore invalid proxy settings while writing");
+                    break;
+            }
+
+            if (written) {
+                out.writeUTF(ID_KEY);
+                if (version < 3) {
+                    out.writeInt(Integer.valueOf(configKey));
+                } else {
+                    out.writeUTF(configKey);
+                }
+            }
+        } catch (NullPointerException e) {
+            loge("Failure in writing " + config + e);
+        }
+        out.writeUTF(EOS);
+
+        return written;
+    }
+
+    /**
+     * @deprecated use {@link #writeIpConfigurations(String, ArrayMap)} instead.
+     * New method uses string as network identifier which could be interface name or MAC address or
+     * other token.
+     */
+    @Deprecated
+    public void writeIpAndProxyConfigurationsToFile(String filePath,
+                                              final SparseArray<IpConfiguration> networks) {
+        mWriter.write(filePath, out -> {
+            out.writeInt(IPCONFIG_FILE_VERSION);
+            for (int i = 0; i < networks.size(); i++) {
+                writeConfig(out, String.valueOf(networks.keyAt(i)), networks.valueAt(i));
+            }
+        });
+    }
+
+    /**
+     *  Write the IP configuration associated to the target networks to the destination path.
+     */
+    public void writeIpConfigurations(String filePath,
+                                      ArrayMap<String, IpConfiguration> networks) {
+        mWriter.write(filePath, out -> {
+            out.writeInt(IPCONFIG_FILE_VERSION);
+            for (int i = 0; i < networks.size(); i++) {
+                writeConfig(out, networks.keyAt(i), networks.valueAt(i));
+            }
+        });
+    }
+
+    /**
+     * Read the IP configuration from the destination path to {@link BufferedInputStream}.
+     */
+    public static ArrayMap<String, IpConfiguration> readIpConfigurations(String filePath) {
+        BufferedInputStream bufferedInputStream;
+        try {
+            bufferedInputStream = new BufferedInputStream(new FileInputStream(filePath));
+        } catch (FileNotFoundException e) {
+            // Return an empty array here because callers expect an empty array when the file is
+            // not present.
+            loge("Error opening configuration file: " + e);
+            return new ArrayMap<>(0);
+        }
+        return readIpConfigurations(bufferedInputStream);
+    }
+
+    /** @deprecated use {@link #readIpConfigurations(String)} */
+    @Deprecated
+    public static SparseArray<IpConfiguration> readIpAndProxyConfigurations(String filePath) {
+        BufferedInputStream bufferedInputStream;
+        try {
+            bufferedInputStream = new BufferedInputStream(new FileInputStream(filePath));
+        } catch (FileNotFoundException e) {
+            // Return an empty array here because callers expect an empty array when the file is
+            // not present.
+            loge("Error opening configuration file: " + e);
+            return new SparseArray<>();
+        }
+        return readIpAndProxyConfigurations(bufferedInputStream);
+    }
+
+    /** @deprecated use {@link #readIpConfigurations(InputStream)} */
+    @Deprecated
+    public static SparseArray<IpConfiguration> readIpAndProxyConfigurations(
+            InputStream inputStream) {
+        ArrayMap<String, IpConfiguration> networks = readIpConfigurations(inputStream);
+        if (networks == null) {
+            return null;
+        }
+
+        SparseArray<IpConfiguration> networksById = new SparseArray<>();
+        for (int i = 0; i < networks.size(); i++) {
+            int id = Integer.valueOf(networks.keyAt(i));
+            networksById.put(id, networks.valueAt(i));
+        }
+
+        return networksById;
+    }
+
+    /** Returns a map of network identity token and {@link IpConfiguration}. */
+    public static ArrayMap<String, IpConfiguration> readIpConfigurations(
+            InputStream inputStream) {
+        ArrayMap<String, IpConfiguration> networks = new ArrayMap<>();
+        DataInputStream in = null;
+        try {
+            in = new DataInputStream(inputStream);
+
+            int version = in.readInt();
+            if (version != 3 && version != 2 && version != 1) {
+                loge("Bad version on IP configuration file, ignore read");
+                return null;
+            }
+
+            while (true) {
+                String uniqueToken = null;
+                // Default is DHCP with no proxy
+                IpAssignment ipAssignment = IpAssignment.DHCP;
+                ProxySettings proxySettings = ProxySettings.NONE;
+                StaticIpConfiguration staticIpConfiguration = new StaticIpConfiguration();
+                LinkAddress linkAddress = null;
+                InetAddress gatewayAddress = null;
+                String proxyHost = null;
+                String pacFileUrl = null;
+                int proxyPort = -1;
+                String exclusionList = null;
+                String key;
+                final List<InetAddress> dnsServers = new ArrayList<>();
+
+                do {
+                    key = in.readUTF();
+                    try {
+                        if (key.equals(ID_KEY)) {
+                            if (version < 3) {
+                                int id = in.readInt();
+                                uniqueToken = String.valueOf(id);
+                            } else {
+                                uniqueToken = in.readUTF();
+                            }
+                        } else if (key.equals(IP_ASSIGNMENT_KEY)) {
+                            ipAssignment = IpAssignment.valueOf(in.readUTF());
+                        } else if (key.equals(LINK_ADDRESS_KEY)) {
+                            LinkAddress parsedLinkAddress =
+                                    new LinkAddress(
+                                            InetAddresses.parseNumericAddress(in.readUTF()),
+                                            in.readInt());
+                            if (parsedLinkAddress.getAddress() instanceof Inet4Address
+                                    && linkAddress == null) {
+                                linkAddress = parsedLinkAddress;
+                            } else {
+                                loge("Non-IPv4 or duplicate address: " + parsedLinkAddress);
+                            }
+                        } else if (key.equals(GATEWAY_KEY)) {
+                            LinkAddress dest = null;
+                            InetAddress gateway = null;
+                            if (version == 1) {
+                                // only supported default gateways - leave the dest/prefix empty
+                                gateway = InetAddresses.parseNumericAddress(in.readUTF());
+                                if (gatewayAddress == null) {
+                                    gatewayAddress = gateway;
+                                } else {
+                                    loge("Duplicate gateway: " + gateway.getHostAddress());
+                                }
+                            } else {
+                                if (in.readInt() == 1) {
+                                    dest =
+                                            new LinkAddress(
+                                                    InetAddresses.parseNumericAddress(in.readUTF()),
+                                                    in.readInt());
+                                }
+                                if (in.readInt() == 1) {
+                                    gateway = InetAddresses.parseNumericAddress(in.readUTF());
+                                }
+                                // If the destination is a default IPv4 route, use the gateway
+                                // address unless already set. If there is no destination, assume
+                                // it is default route and use the gateway address in all cases.
+                                if (dest == null) {
+                                    gatewayAddress = gateway;
+                                } else if (dest.getAddress() instanceof Inet4Address
+                                        && dest.getPrefixLength() == 0 && gatewayAddress == null) {
+                                    gatewayAddress = gateway;
+                                } else {
+                                    loge("Non-IPv4 default or duplicate route: "
+                                            + dest.getAddress());
+                                }
+                            }
+                        } else if (key.equals(DNS_KEY)) {
+                            dnsServers.add(InetAddresses.parseNumericAddress(in.readUTF()));
+                        } else if (key.equals(PROXY_SETTINGS_KEY)) {
+                            proxySettings = ProxySettings.valueOf(in.readUTF());
+                        } else if (key.equals(PROXY_HOST_KEY)) {
+                            proxyHost = in.readUTF();
+                        } else if (key.equals(PROXY_PORT_KEY)) {
+                            proxyPort = in.readInt();
+                        } else if (key.equals(PROXY_PAC_FILE)) {
+                            pacFileUrl = in.readUTF();
+                        } else if (key.equals(EXCLUSION_LIST_KEY)) {
+                            exclusionList = in.readUTF();
+                        } else if (key.equals(EOS)) {
+                            break;
+                        } else {
+                            loge("Ignore unknown key " + key + "while reading");
+                        }
+                    } catch (IllegalArgumentException e) {
+                        loge("Ignore invalid address while reading" + e);
+                    }
+                } while (true);
+
+                staticIpConfiguration = new StaticIpConfiguration.Builder()
+                    .setIpAddress(linkAddress)
+                    .setGateway(gatewayAddress)
+                    .setDnsServers(dnsServers)
+                    .build();
+
+                if (uniqueToken != null) {
+                    IpConfiguration config = new IpConfiguration();
+                    networks.put(uniqueToken, config);
+
+                    switch (ipAssignment) {
+                        case STATIC:
+                            config.setStaticIpConfiguration(staticIpConfiguration);
+                            config.setIpAssignment(ipAssignment);
+                            break;
+                        case DHCP:
+                            config.setIpAssignment(ipAssignment);
+                            break;
+                        case UNASSIGNED:
+                            loge("BUG: Found UNASSIGNED IP on file, use DHCP");
+                            config.setIpAssignment(IpAssignment.DHCP);
+                            break;
+                        default:
+                            loge("Ignore invalid ip assignment while reading.");
+                            config.setIpAssignment(IpAssignment.UNASSIGNED);
+                            break;
+                    }
+
+                    switch (proxySettings) {
+                        case STATIC:
+                            ProxyInfo proxyInfo = ProxyInfo.buildDirectProxy(proxyHost, proxyPort,
+                                    ProxyUtils.exclusionStringAsList(exclusionList));
+                            config.setProxySettings(proxySettings);
+                            config.setHttpProxy(proxyInfo);
+                            break;
+                        case PAC:
+                            ProxyInfo proxyPacProperties =
+                                    ProxyInfo.buildPacProxy(Uri.parse(pacFileUrl));
+                            config.setProxySettings(proxySettings);
+                            config.setHttpProxy(proxyPacProperties);
+                            break;
+                        case NONE:
+                            config.setProxySettings(proxySettings);
+                            break;
+                        case UNASSIGNED:
+                            loge("BUG: Found UNASSIGNED proxy on file, use NONE");
+                            config.setProxySettings(ProxySettings.NONE);
+                            break;
+                        default:
+                            loge("Ignore invalid proxy settings while reading");
+                            config.setProxySettings(ProxySettings.UNASSIGNED);
+                            break;
+                    }
+                } else {
+                    if (DBG) log("Missing id while parsing configuration");
+                }
+            }
+        } catch (EOFException ignore) {
+        } catch (IOException e) {
+            loge("Error parsing configuration: " + e);
+        } finally {
+            if (in != null) {
+                try {
+                    in.close();
+                } catch (Exception e) { }
+            }
+        }
+
+        return networks;
+    }
+
+    protected static void loge(String s) {
+        Log.e(TAG, s);
+    }
+
+    protected static void log(String s) {
+        Log.d(TAG, s);
+    }
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsFactory.java b/service-t/src/com/android/server/net/NetworkStatsFactory.java
new file mode 100644
index 0000000..3b93f1a
--- /dev/null
+++ b/service-t/src/com/android/server/net/NetworkStatsFactory.java
@@ -0,0 +1,505 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static android.net.NetworkStats.INTERFACES_ALL;
+import static android.net.NetworkStats.SET_ALL;
+import static android.net.NetworkStats.TAG_ALL;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.NetworkStats.UID_ALL;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.Context;
+import android.net.NetworkStats;
+import android.net.UnderlyingNetworkInfo;
+import android.os.ServiceSpecificException;
+import android.os.StrictMode;
+import android.os.SystemClock;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.ProcFileReader;
+import com.android.net.module.util.CollectionUtils;
+import com.android.server.BpfNetMaps;
+
+import libcore.io.IoUtils;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.net.ProtocolException;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Creates {@link NetworkStats} instances by parsing various {@code /proc/}
+ * files as needed.
+ *
+ * @hide
+ */
+public class NetworkStatsFactory {
+    static {
+        System.loadLibrary("service-connectivity");
+    }
+
+    private static final String TAG = "NetworkStatsFactory";
+
+    private static final boolean USE_NATIVE_PARSING = true;
+    private static final boolean VALIDATE_NATIVE_STATS = false;
+
+    /** Path to {@code /proc/net/xt_qtaguid/iface_stat_all}. */
+    private final File mStatsXtIfaceAll;
+    /** Path to {@code /proc/net/xt_qtaguid/iface_stat_fmt}. */
+    private final File mStatsXtIfaceFmt;
+    /** Path to {@code /proc/net/xt_qtaguid/stats}. */
+    private final File mStatsXtUid;
+
+    private final boolean mUseBpfStats;
+
+    private final Context mContext;
+
+    private final BpfNetMaps mBpfNetMaps;
+
+    /**
+     * Guards persistent data access in this class
+     *
+     * <p>In order to prevent deadlocks, critical sections protected by this lock SHALL NOT call out
+     * to other code that will acquire other locks within the system server. See b/134244752.
+     */
+    private final Object mPersistentDataLock = new Object();
+
+    /** Set containing info about active VPNs and their underlying networks. */
+    private volatile UnderlyingNetworkInfo[] mUnderlyingNetworkInfos = new UnderlyingNetworkInfo[0];
+
+    // A persistent snapshot of cumulative stats since device start
+    @GuardedBy("mPersistentDataLock")
+    private NetworkStats mPersistSnapshot;
+
+    // The persistent snapshot of tun and 464xlat adjusted stats since device start
+    @GuardedBy("mPersistentDataLock")
+    private NetworkStats mTunAnd464xlatAdjustedStats;
+
+    /**
+     * (Stacked interface) -> (base interface) association for all connected ifaces since boot.
+     *
+     * Because counters must never roll backwards, once a given interface is stacked on top of an
+     * underlying interface, the stacked interface can never be stacked on top of
+     * another interface. */
+    private final ConcurrentHashMap<String, String> mStackedIfaces
+            = new ConcurrentHashMap<>();
+
+    /** Informs the factory of a new stacked interface. */
+    public void noteStackedIface(String stackedIface, String baseIface) {
+        if (stackedIface != null && baseIface != null) {
+            mStackedIfaces.put(stackedIface, baseIface);
+        }
+    }
+
+    /**
+     * Set active VPN information for data usage migration purposes
+     *
+     * <p>Traffic on TUN-based VPNs inherently all appear to be originated from the VPN providing
+     * app's UID. This method is used to support migration of VPN data usage, ensuring data is
+     * accurately billed to the real owner of the traffic.
+     *
+     * @param vpnArray The snapshot of the currently-running VPNs.
+     */
+    public void updateUnderlyingNetworkInfos(UnderlyingNetworkInfo[] vpnArray) {
+        mUnderlyingNetworkInfos = vpnArray.clone();
+    }
+
+    /**
+     * Get a set of interfaces containing specified ifaces and stacked interfaces.
+     *
+     * <p>The added stacked interfaces are ifaces stacked on top of the specified ones, or ifaces
+     * on which the specified ones are stacked. Stacked interfaces are those noted with
+     * {@link #noteStackedIface(String, String)}, but only interfaces noted before this method
+     * is called are guaranteed to be included.
+     */
+    public String[] augmentWithStackedInterfaces(@Nullable String[] requiredIfaces) {
+        if (requiredIfaces == NetworkStats.INTERFACES_ALL) {
+            return null;
+        }
+
+        HashSet<String> relatedIfaces = new HashSet<>(Arrays.asList(requiredIfaces));
+        // ConcurrentHashMap's EntrySet iterators are "guaranteed to traverse
+        // elements as they existed upon construction exactly once, and may
+        // (but are not guaranteed to) reflect any modifications subsequent to construction".
+        // This is enough here.
+        for (Map.Entry<String, String> entry : mStackedIfaces.entrySet()) {
+            if (relatedIfaces.contains(entry.getKey())) {
+                relatedIfaces.add(entry.getValue());
+            } else if (relatedIfaces.contains(entry.getValue())) {
+                relatedIfaces.add(entry.getKey());
+            }
+        }
+
+        String[] outArray = new String[relatedIfaces.size()];
+        return relatedIfaces.toArray(outArray);
+    }
+
+    /**
+     * Applies 464xlat adjustments with ifaces noted with {@link #noteStackedIface(String, String)}.
+     * @see NetworkStats#apply464xlatAdjustments(NetworkStats, NetworkStats, Map)
+     */
+    public void apply464xlatAdjustments(NetworkStats baseTraffic, NetworkStats stackedTraffic) {
+        NetworkStats.apply464xlatAdjustments(baseTraffic, stackedTraffic, mStackedIfaces);
+    }
+
+    public NetworkStatsFactory(@NonNull Context ctx) {
+        this(ctx, new File("/proc/"), true);
+    }
+
+    @VisibleForTesting
+    public NetworkStatsFactory(@NonNull Context ctx, File procRoot, boolean useBpfStats) {
+        mStatsXtIfaceAll = new File(procRoot, "net/xt_qtaguid/iface_stat_all");
+        mStatsXtIfaceFmt = new File(procRoot, "net/xt_qtaguid/iface_stat_fmt");
+        mStatsXtUid = new File(procRoot, "net/xt_qtaguid/stats");
+        mUseBpfStats = useBpfStats;
+        mBpfNetMaps = new BpfNetMaps();
+        synchronized (mPersistentDataLock) {
+            mPersistSnapshot = new NetworkStats(SystemClock.elapsedRealtime(), -1);
+            mTunAnd464xlatAdjustedStats = new NetworkStats(SystemClock.elapsedRealtime(), -1);
+        }
+        mContext = ctx;
+    }
+
+    public NetworkStats readBpfNetworkStatsDev() throws IOException {
+        final NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 6);
+        if (nativeReadNetworkStatsDev(stats) != 0) {
+            throw new IOException("Failed to parse bpf iface stats");
+        }
+        return stats;
+    }
+
+    /**
+     * Parse and return interface-level summary {@link NetworkStats} measured
+     * using {@code /proc/net/dev} style hooks, which may include non IP layer
+     * traffic. Values monotonically increase since device boot, and may include
+     * details about inactive interfaces.
+     *
+     * @throws IllegalStateException when problem parsing stats.
+     */
+    public NetworkStats readNetworkStatsSummaryDev() throws IOException {
+
+        // Return xt_bpf stats if switched to bpf module.
+        if (mUseBpfStats)
+            return readBpfNetworkStatsDev();
+
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+
+        final NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 6);
+        final NetworkStats.Entry entry = new NetworkStats.Entry();
+
+        ProcFileReader reader = null;
+        try {
+            reader = new ProcFileReader(new FileInputStream(mStatsXtIfaceAll));
+
+            while (reader.hasMoreData()) {
+                entry.iface = reader.nextString();
+                entry.uid = UID_ALL;
+                entry.set = SET_ALL;
+                entry.tag = TAG_NONE;
+
+                final boolean active = reader.nextInt() != 0;
+
+                // always include snapshot values
+                entry.rxBytes = reader.nextLong();
+                entry.rxPackets = reader.nextLong();
+                entry.txBytes = reader.nextLong();
+                entry.txPackets = reader.nextLong();
+
+                // fold in active numbers, but only when active
+                if (active) {
+                    entry.rxBytes += reader.nextLong();
+                    entry.rxPackets += reader.nextLong();
+                    entry.txBytes += reader.nextLong();
+                    entry.txPackets += reader.nextLong();
+                }
+
+                stats.insertEntry(entry);
+                reader.finishLine();
+            }
+        } catch (NullPointerException|NumberFormatException e) {
+            throw protocolExceptionWithCause("problem parsing stats", e);
+        } finally {
+            IoUtils.closeQuietly(reader);
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+        return stats;
+    }
+
+    /**
+     * Parse and return interface-level summary {@link NetworkStats}. Designed
+     * to return only IP layer traffic. Values monotonically increase since
+     * device boot, and may include details about inactive interfaces.
+     *
+     * @throws IllegalStateException when problem parsing stats.
+     */
+    public NetworkStats readNetworkStatsSummaryXt() throws IOException {
+
+        // Return xt_bpf stats if qtaguid  module is replaced.
+        if (mUseBpfStats)
+            return readBpfNetworkStatsDev();
+
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+
+        // return null when kernel doesn't support
+        if (!mStatsXtIfaceFmt.exists()) return null;
+
+        final NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 6);
+        final NetworkStats.Entry entry = new NetworkStats.Entry();
+
+        ProcFileReader reader = null;
+        try {
+            // open and consume header line
+            reader = new ProcFileReader(new FileInputStream(mStatsXtIfaceFmt));
+            reader.finishLine();
+
+            while (reader.hasMoreData()) {
+                entry.iface = reader.nextString();
+                entry.uid = UID_ALL;
+                entry.set = SET_ALL;
+                entry.tag = TAG_NONE;
+
+                entry.rxBytes = reader.nextLong();
+                entry.rxPackets = reader.nextLong();
+                entry.txBytes = reader.nextLong();
+                entry.txPackets = reader.nextLong();
+
+                stats.insertEntry(entry);
+                reader.finishLine();
+            }
+        } catch (NullPointerException|NumberFormatException e) {
+            throw protocolExceptionWithCause("problem parsing stats", e);
+        } finally {
+            IoUtils.closeQuietly(reader);
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+        return stats;
+    }
+
+    public NetworkStats readNetworkStatsDetail() throws IOException {
+        return readNetworkStatsDetail(UID_ALL, INTERFACES_ALL, TAG_ALL);
+    }
+
+    @GuardedBy("mPersistentDataLock")
+    private void requestSwapActiveStatsMapLocked() throws IOException {
+        try {
+            // Do a active map stats swap. Once the swap completes, this code
+            // can read and clean the inactive map without races.
+            mBpfNetMaps.swapActiveStatsMap();
+        } catch (ServiceSpecificException e) {
+            throw new IOException(e);
+        }
+    }
+
+    /**
+     * Reads the detailed UID stats based on the provided parameters
+     *
+     * @param limitUid the UID to limit this query to
+     * @param limitIfaces the interfaces to limit this query to. Use {@link
+     *     NetworkStats.INTERFACES_ALL} to select all interfaces
+     * @param limitTag the tags to limit this query to
+     * @return the NetworkStats instance containing network statistics at the present time.
+     */
+    public NetworkStats readNetworkStatsDetail(
+            int limitUid, String[] limitIfaces, int limitTag) throws IOException {
+        // In order to prevent deadlocks, anything protected by this lock MUST NOT call out to other
+        // code that will acquire other locks within the system server. See b/134244752.
+        synchronized (mPersistentDataLock) {
+            // Take a reference. If this gets swapped out, we still have the old reference.
+            final UnderlyingNetworkInfo[] vpnArray = mUnderlyingNetworkInfos;
+            // Take a defensive copy. mPersistSnapshot is mutated in some cases below
+            final NetworkStats prev = mPersistSnapshot.clone();
+
+            if (USE_NATIVE_PARSING) {
+                final NetworkStats stats =
+                        new NetworkStats(SystemClock.elapsedRealtime(), 0 /* initialSize */);
+                if (mUseBpfStats) {
+                    requestSwapActiveStatsMapLocked();
+                    // Stats are always read from the inactive map, so they must be read after the
+                    // swap
+                    if (nativeReadNetworkStatsDetail(stats, mStatsXtUid.getAbsolutePath(), UID_ALL,
+                            INTERFACES_ALL, TAG_ALL, mUseBpfStats) != 0) {
+                        throw new IOException("Failed to parse network stats");
+                    }
+
+                    // BPF stats are incremental; fold into mPersistSnapshot.
+                    mPersistSnapshot.setElapsedRealtime(stats.getElapsedRealtime());
+                    mPersistSnapshot.combineAllValues(stats);
+                } else {
+                    if (nativeReadNetworkStatsDetail(stats, mStatsXtUid.getAbsolutePath(), UID_ALL,
+                            INTERFACES_ALL, TAG_ALL, mUseBpfStats) != 0) {
+                        throw new IOException("Failed to parse network stats");
+                    }
+                    if (VALIDATE_NATIVE_STATS) {
+                        final NetworkStats javaStats = javaReadNetworkStatsDetail(mStatsXtUid,
+                                UID_ALL, INTERFACES_ALL, TAG_ALL);
+                        assertEquals(javaStats, stats);
+                    }
+
+                    mPersistSnapshot = stats;
+                }
+            } else {
+                mPersistSnapshot = javaReadNetworkStatsDetail(mStatsXtUid, UID_ALL, INTERFACES_ALL,
+                        TAG_ALL);
+            }
+
+            NetworkStats adjustedStats = adjustForTunAnd464Xlat(mPersistSnapshot, prev, vpnArray);
+
+            // Filter return values
+            adjustedStats.filter(limitUid, limitIfaces, limitTag);
+            return adjustedStats;
+        }
+    }
+
+    @GuardedBy("mPersistentDataLock")
+    private NetworkStats adjustForTunAnd464Xlat(NetworkStats uidDetailStats,
+            NetworkStats previousStats, UnderlyingNetworkInfo[] vpnArray) {
+        // Calculate delta from last snapshot
+        final NetworkStats delta = uidDetailStats.subtract(previousStats);
+
+        // Apply 464xlat adjustments before VPN adjustments. If VPNs are using v4 on a v6 only
+        // network, the overhead is their fault.
+        // No locking here: apply464xlatAdjustments behaves fine with an add-only
+        // ConcurrentHashMap.
+        delta.apply464xlatAdjustments(mStackedIfaces);
+
+        // Migrate data usage over a VPN to the TUN network.
+        for (UnderlyingNetworkInfo info : vpnArray) {
+            delta.migrateTun(info.getOwnerUid(), info.getInterface(),
+                    info.getUnderlyingInterfaces());
+            // Filter out debug entries as that may lead to over counting.
+            delta.filterDebugEntries();
+        }
+
+        // Update mTunAnd464xlatAdjustedStats with migrated delta.
+        mTunAnd464xlatAdjustedStats.combineAllValues(delta);
+        mTunAnd464xlatAdjustedStats.setElapsedRealtime(uidDetailStats.getElapsedRealtime());
+
+        return mTunAnd464xlatAdjustedStats.clone();
+    }
+
+    /**
+     * Parse and return {@link NetworkStats} with UID-level details. Values are
+     * expected to monotonically increase since device boot.
+     */
+    @VisibleForTesting
+    public static NetworkStats javaReadNetworkStatsDetail(File detailPath, int limitUid,
+            String[] limitIfaces, int limitTag)
+            throws IOException {
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+
+        final NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 24);
+        final NetworkStats.Entry entry = new NetworkStats.Entry();
+
+        int idx = 1;
+        int lastIdx = 1;
+
+        ProcFileReader reader = null;
+        try {
+            // open and consume header line
+            reader = new ProcFileReader(new FileInputStream(detailPath));
+            reader.finishLine();
+
+            while (reader.hasMoreData()) {
+                idx = reader.nextInt();
+                if (idx != lastIdx + 1) {
+                    throw new ProtocolException(
+                            "inconsistent idx=" + idx + " after lastIdx=" + lastIdx);
+                }
+                lastIdx = idx;
+
+                entry.iface = reader.nextString();
+                entry.tag = kernelToTag(reader.nextString());
+                entry.uid = reader.nextInt();
+                entry.set = reader.nextInt();
+                entry.rxBytes = reader.nextLong();
+                entry.rxPackets = reader.nextLong();
+                entry.txBytes = reader.nextLong();
+                entry.txPackets = reader.nextLong();
+
+                if ((limitIfaces == null || CollectionUtils.contains(limitIfaces, entry.iface))
+                        && (limitUid == UID_ALL || limitUid == entry.uid)
+                        && (limitTag == TAG_ALL || limitTag == entry.tag)) {
+                    stats.insertEntry(entry);
+                }
+
+                reader.finishLine();
+            }
+        } catch (NullPointerException|NumberFormatException e) {
+            throw protocolExceptionWithCause("problem parsing idx " + idx, e);
+        } finally {
+            IoUtils.closeQuietly(reader);
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+
+        return stats;
+    }
+
+    public void assertEquals(NetworkStats expected, NetworkStats actual) {
+        if (expected.size() != actual.size()) {
+            throw new AssertionError(
+                    "Expected size " + expected.size() + ", actual size " + actual.size());
+        }
+
+        NetworkStats.Entry expectedRow = null;
+        NetworkStats.Entry actualRow = null;
+        for (int i = 0; i < expected.size(); i++) {
+            expectedRow = expected.getValues(i, expectedRow);
+            actualRow = actual.getValues(i, actualRow);
+            if (!expectedRow.equals(actualRow)) {
+                throw new AssertionError(
+                        "Expected row " + i + ": " + expectedRow + ", actual row " + actualRow);
+            }
+        }
+    }
+
+    /**
+     * Convert {@code /proc/} tag format to {@link Integer}. Assumes incoming
+     * format like {@code 0x7fffffff00000000}.
+     */
+    public static int kernelToTag(String string) {
+        int length = string.length();
+        if (length > 10) {
+            return Long.decode(string.substring(0, length - 8)).intValue();
+        } else {
+            return 0;
+        }
+    }
+
+    /**
+     * Parse statistics from file into given {@link NetworkStats} object. Values
+     * are expected to monotonically increase since device boot.
+     */
+    @VisibleForTesting
+    public static native int nativeReadNetworkStatsDetail(NetworkStats stats, String path,
+        int limitUid, String[] limitIfaces, int limitTag, boolean useBpfStats);
+
+    @VisibleForTesting
+    public static native int nativeReadNetworkStatsDev(NetworkStats stats);
+
+    private static ProtocolException protocolExceptionWithCause(String message, Throwable cause) {
+        ProtocolException pe = new ProtocolException(message);
+        pe.initCause(cause);
+        return pe;
+    }
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsObservers.java b/service-t/src/com/android/server/net/NetworkStatsObservers.java
new file mode 100644
index 0000000..fdfc893
--- /dev/null
+++ b/service-t/src/com/android/server/net/NetworkStatsObservers.java
@@ -0,0 +1,451 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static android.app.usage.NetworkStatsManager.MIN_THRESHOLD_BYTES;
+
+import android.app.usage.NetworkStatsManager;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.net.DataUsageRequest;
+import android.net.NetworkIdentitySet;
+import android.net.NetworkStack;
+import android.net.NetworkStats;
+import android.net.NetworkStatsAccess;
+import android.net.NetworkStatsCollection;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.netstats.IUsageCallback;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.IBinder;
+import android.os.Looper;
+import android.os.Message;
+import android.os.Process;
+import android.os.RemoteException;
+import android.util.ArrayMap;
+import android.util.Log;
+import android.util.SparseArray;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Manages observers of {@link NetworkStats}. Allows observers to be notified when
+ * data usage has been reported in {@link NetworkStatsService}. An observer can set
+ * a threshold of how much data it cares about to be notified.
+ */
+class NetworkStatsObservers {
+    private static final String TAG = "NetworkStatsObservers";
+    private static final boolean LOGV = false;
+
+    private static final int MSG_REGISTER = 1;
+    private static final int MSG_UNREGISTER = 2;
+    private static final int MSG_UPDATE_STATS = 3;
+
+    // All access to this map must be done from the handler thread.
+    // indexed by DataUsageRequest#requestId
+    private final SparseArray<RequestInfo> mDataUsageRequests = new SparseArray<>();
+
+    // Sequence number of DataUsageRequests
+    private final AtomicInteger mNextDataUsageRequestId = new AtomicInteger();
+
+    // Lazily instantiated when an observer is registered.
+    private volatile Handler mHandler;
+
+    /**
+     * Creates a wrapper that contains the caller context and a normalized request.
+     * The request should be returned to the caller app, and the wrapper should be sent to this
+     * object through #addObserver by the service handler.
+     *
+     * <p>It will register the observer asynchronously, so it is safe to call from any thread.
+     *
+     * @return the normalized request wrapped within {@link RequestInfo}.
+     */
+    public DataUsageRequest register(Context context, DataUsageRequest inputRequest,
+            IUsageCallback callback, int callingUid, @NetworkStatsAccess.Level int accessLevel) {
+        DataUsageRequest request = buildRequest(context, inputRequest, callingUid);
+        RequestInfo requestInfo = buildRequestInfo(request, callback, callingUid,
+                accessLevel);
+
+        if (LOGV) Log.v(TAG, "Registering observer for " + request);
+        getHandler().sendMessage(mHandler.obtainMessage(MSG_REGISTER, requestInfo));
+        return request;
+    }
+
+    /**
+     * Unregister a data usage observer.
+     *
+     * <p>It will unregister the observer asynchronously, so it is safe to call from any thread.
+     */
+    public void unregister(DataUsageRequest request, int callingUid) {
+        getHandler().sendMessage(mHandler.obtainMessage(MSG_UNREGISTER, callingUid, 0 /* ignore */,
+                request));
+    }
+
+    /**
+     * Updates data usage statistics of registered observers and notifies if limits are reached.
+     *
+     * <p>It will update stats asynchronously, so it is safe to call from any thread.
+     */
+    public void updateStats(NetworkStats xtSnapshot, NetworkStats uidSnapshot,
+                ArrayMap<String, NetworkIdentitySet> activeIfaces,
+                ArrayMap<String, NetworkIdentitySet> activeUidIfaces,
+                long currentTime) {
+        StatsContext statsContext = new StatsContext(xtSnapshot, uidSnapshot, activeIfaces,
+                activeUidIfaces, currentTime);
+        getHandler().sendMessage(mHandler.obtainMessage(MSG_UPDATE_STATS, statsContext));
+    }
+
+    private Handler getHandler() {
+        if (mHandler == null) {
+            synchronized (this) {
+                if (mHandler == null) {
+                    if (LOGV) Log.v(TAG, "Creating handler");
+                    mHandler = new Handler(getHandlerLooperLocked(), mHandlerCallback);
+                }
+            }
+        }
+        return mHandler;
+    }
+
+    @VisibleForTesting
+    protected Looper getHandlerLooperLocked() {
+        HandlerThread handlerThread = new HandlerThread(TAG);
+        handlerThread.start();
+        return handlerThread.getLooper();
+    }
+
+    private Handler.Callback mHandlerCallback = new Handler.Callback() {
+        @Override
+        public boolean handleMessage(Message msg) {
+            switch (msg.what) {
+                case MSG_REGISTER: {
+                    handleRegister((RequestInfo) msg.obj);
+                    return true;
+                }
+                case MSG_UNREGISTER: {
+                    handleUnregister((DataUsageRequest) msg.obj, msg.arg1 /* callingUid */);
+                    return true;
+                }
+                case MSG_UPDATE_STATS: {
+                    handleUpdateStats((StatsContext) msg.obj);
+                    return true;
+                }
+                default: {
+                    return false;
+                }
+            }
+        }
+    };
+
+    /**
+     * Adds a {@link RequestInfo} as an observer.
+     * Should only be called from the handler thread otherwise there will be a race condition
+     * on mDataUsageRequests.
+     */
+    private void handleRegister(RequestInfo requestInfo) {
+        mDataUsageRequests.put(requestInfo.mRequest.requestId, requestInfo);
+    }
+
+    /**
+     * Removes a {@link DataUsageRequest} if the calling uid is authorized.
+     * Should only be called from the handler thread otherwise there will be a race condition
+     * on mDataUsageRequests.
+     */
+    private void handleUnregister(DataUsageRequest request, int callingUid) {
+        RequestInfo requestInfo;
+        requestInfo = mDataUsageRequests.get(request.requestId);
+        if (requestInfo == null) {
+            if (LOGV) Log.v(TAG, "Trying to unregister unknown request " + request);
+            return;
+        }
+        if (Process.SYSTEM_UID != callingUid && requestInfo.mCallingUid != callingUid) {
+            Log.w(TAG, "Caller uid " + callingUid + " is not owner of " + request);
+            return;
+        }
+
+        if (LOGV) Log.v(TAG, "Unregistering " + request);
+        mDataUsageRequests.remove(request.requestId);
+        requestInfo.unlinkDeathRecipient();
+        requestInfo.callCallback(NetworkStatsManager.CALLBACK_RELEASED);
+    }
+
+    private void handleUpdateStats(StatsContext statsContext) {
+        if (mDataUsageRequests.size() == 0) {
+            return;
+        }
+
+        for (int i = 0; i < mDataUsageRequests.size(); i++) {
+            RequestInfo requestInfo = mDataUsageRequests.valueAt(i);
+            requestInfo.updateStats(statsContext);
+        }
+    }
+
+    private DataUsageRequest buildRequest(Context context, DataUsageRequest request,
+                int callingUid) {
+        // For non-NETWORK_STACK permission uid, cap the minimum threshold to a safe default to
+        // avoid too many callbacks.
+        final long thresholdInBytes = (context.checkPermission(
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK, Process.myPid(), callingUid)
+                == PackageManager.PERMISSION_GRANTED ? request.thresholdInBytes
+                : Math.max(MIN_THRESHOLD_BYTES, request.thresholdInBytes));
+        if (thresholdInBytes > request.thresholdInBytes) {
+            Log.w(TAG, "Threshold was too low for " + request
+                    + ". Overriding to a safer default of " + thresholdInBytes + " bytes");
+        }
+        return new DataUsageRequest(mNextDataUsageRequestId.incrementAndGet(),
+                request.template, thresholdInBytes);
+    }
+
+    private RequestInfo buildRequestInfo(DataUsageRequest request, IUsageCallback callback,
+            int callingUid, @NetworkStatsAccess.Level int accessLevel) {
+        if (accessLevel <= NetworkStatsAccess.Level.USER) {
+            return new UserUsageRequestInfo(this, request, callback, callingUid,
+                    accessLevel);
+        } else {
+            // Safety check in case a new access level is added and we forgot to update this
+            if (accessLevel < NetworkStatsAccess.Level.DEVICESUMMARY) {
+                throw new IllegalArgumentException(
+                        "accessLevel " + accessLevel + " is less than DEVICESUMMARY.");
+            }
+            return new NetworkUsageRequestInfo(this, request, callback, callingUid,
+                    accessLevel);
+        }
+    }
+
+    /**
+     * Tracks information relevant to a data usage observer.
+     * It will notice when the calling process dies so we can self-expire.
+     */
+    private abstract static class RequestInfo implements IBinder.DeathRecipient {
+        private final NetworkStatsObservers mStatsObserver;
+        protected final DataUsageRequest mRequest;
+        private final IUsageCallback mCallback;
+        protected final int mCallingUid;
+        protected final @NetworkStatsAccess.Level int mAccessLevel;
+        protected NetworkStatsRecorder mRecorder;
+        protected NetworkStatsCollection mCollection;
+
+        RequestInfo(NetworkStatsObservers statsObserver, DataUsageRequest request,
+                IUsageCallback callback, int callingUid,
+                    @NetworkStatsAccess.Level int accessLevel) {
+            mStatsObserver = statsObserver;
+            mRequest = request;
+            mCallback = callback;
+            mCallingUid = callingUid;
+            mAccessLevel = accessLevel;
+
+            try {
+                mCallback.asBinder().linkToDeath(this, 0);
+            } catch (RemoteException e) {
+                binderDied();
+            }
+        }
+
+        @Override
+        public void binderDied() {
+            if (LOGV) {
+                Log.v(TAG, "RequestInfo binderDied(" + mRequest + ", " + mCallback + ")");
+            }
+            mStatsObserver.unregister(mRequest, Process.SYSTEM_UID);
+            callCallback(NetworkStatsManager.CALLBACK_RELEASED);
+        }
+
+        @Override
+        public String toString() {
+            return "RequestInfo from uid:" + mCallingUid
+                    + " for " + mRequest + " accessLevel:" + mAccessLevel;
+        }
+
+        private void unlinkDeathRecipient() {
+            mCallback.asBinder().unlinkToDeath(this, 0);
+        }
+
+        /**
+         * Update stats given the samples and interface to identity mappings.
+         */
+        private void updateStats(StatsContext statsContext) {
+            if (mRecorder == null) {
+                // First run; establish baseline stats
+                resetRecorder();
+                recordSample(statsContext);
+                return;
+            }
+            recordSample(statsContext);
+
+            if (checkStats()) {
+                resetRecorder();
+                callCallback(NetworkStatsManager.CALLBACK_LIMIT_REACHED);
+            }
+        }
+
+        private void callCallback(int callbackType) {
+            try {
+                if (LOGV) {
+                    Log.v(TAG, "sending notification " + callbackTypeToName(callbackType)
+                            + " for " + mRequest);
+                }
+                switch (callbackType) {
+                    case NetworkStatsManager.CALLBACK_LIMIT_REACHED:
+                        mCallback.onThresholdReached(mRequest);
+                        break;
+                    case NetworkStatsManager.CALLBACK_RELEASED:
+                        mCallback.onCallbackReleased(mRequest);
+                        break;
+                }
+            } catch (RemoteException e) {
+                // May occur naturally in the race of binder death.
+                Log.w(TAG, "RemoteException caught trying to send a callback msg for " + mRequest);
+            }
+        }
+
+        private void resetRecorder() {
+            mRecorder = new NetworkStatsRecorder();
+            mCollection = mRecorder.getSinceBoot();
+        }
+
+        protected abstract boolean checkStats();
+
+        protected abstract void recordSample(StatsContext statsContext);
+
+        private String callbackTypeToName(int callbackType) {
+            switch (callbackType) {
+                case NetworkStatsManager.CALLBACK_LIMIT_REACHED:
+                    return "LIMIT_REACHED";
+                case NetworkStatsManager.CALLBACK_RELEASED:
+                    return "RELEASED";
+                default:
+                    return "UNKNOWN";
+            }
+        }
+    }
+
+    private static class NetworkUsageRequestInfo extends RequestInfo {
+        NetworkUsageRequestInfo(NetworkStatsObservers statsObserver, DataUsageRequest request,
+                IUsageCallback callback, int callingUid,
+                    @NetworkStatsAccess.Level int accessLevel) {
+            super(statsObserver, request, callback, callingUid, accessLevel);
+        }
+
+        @Override
+        protected boolean checkStats() {
+            long bytesSoFar = getTotalBytesForNetwork(mRequest.template);
+            if (LOGV) {
+                Log.v(TAG, bytesSoFar + " bytes so far since notification for "
+                        + mRequest.template);
+            }
+            if (bytesSoFar > mRequest.thresholdInBytes) {
+                return true;
+            }
+            return false;
+        }
+
+        @Override
+        protected void recordSample(StatsContext statsContext) {
+            // Recorder does not need to be locked in this context since only the handler
+            // thread will update it. We pass a null VPN array because usage is aggregated by uid
+            // for this snapshot, so VPN traffic can't be reattributed to responsible apps.
+            mRecorder.recordSnapshotLocked(statsContext.mXtSnapshot, statsContext.mActiveIfaces,
+                    statsContext.mCurrentTime);
+        }
+
+        /**
+         * Reads stats matching the given template. {@link NetworkStatsCollection} will aggregate
+         * over all buckets, which in this case should be only one since we built it big enough
+         * that it will outlive the caller. If it doesn't, then there will be multiple buckets.
+         */
+        private long getTotalBytesForNetwork(NetworkTemplate template) {
+            NetworkStats stats = mCollection.getSummary(template,
+                    Long.MIN_VALUE /* start */, Long.MAX_VALUE /* end */,
+                    mAccessLevel, mCallingUid);
+            return stats.getTotalBytes();
+        }
+    }
+
+    private static class UserUsageRequestInfo extends RequestInfo {
+        UserUsageRequestInfo(NetworkStatsObservers statsObserver, DataUsageRequest request,
+                    IUsageCallback callback, int callingUid,
+                    @NetworkStatsAccess.Level int accessLevel) {
+            super(statsObserver, request, callback, callingUid, accessLevel);
+        }
+
+        @Override
+        protected boolean checkStats() {
+            int[] uidsToMonitor = mCollection.getRelevantUids(mAccessLevel, mCallingUid);
+
+            for (int i = 0; i < uidsToMonitor.length; i++) {
+                long bytesSoFar = getTotalBytesForNetworkUid(mRequest.template, uidsToMonitor[i]);
+                if (bytesSoFar > mRequest.thresholdInBytes) {
+                    return true;
+                }
+            }
+            return false;
+        }
+
+        @Override
+        protected void recordSample(StatsContext statsContext) {
+            // Recorder does not need to be locked in this context since only the handler
+            // thread will update it. We pass the VPN info so VPN traffic is reattributed to
+            // responsible apps.
+            mRecorder.recordSnapshotLocked(statsContext.mUidSnapshot, statsContext.mActiveUidIfaces,
+                    statsContext.mCurrentTime);
+        }
+
+        /**
+         * Reads all stats matching the given template and uid. Ther history will likely only
+         * contain one bucket per ident since we build it big enough that it will outlive the
+         * caller lifetime.
+         */
+        private long getTotalBytesForNetworkUid(NetworkTemplate template, int uid) {
+            try {
+                NetworkStatsHistory history = mCollection.getHistory(template, null, uid,
+                        NetworkStats.SET_ALL, NetworkStats.TAG_NONE,
+                        NetworkStatsHistory.FIELD_ALL,
+                        Long.MIN_VALUE /* start */, Long.MAX_VALUE /* end */,
+                        mAccessLevel, mCallingUid);
+                return history.getTotalBytes();
+            } catch (SecurityException e) {
+                if (LOGV) {
+                    Log.w(TAG, "CallerUid " + mCallingUid + " may have lost access to uid "
+                            + uid);
+                }
+                return 0;
+            }
+        }
+    }
+
+    private static class StatsContext {
+        NetworkStats mXtSnapshot;
+        NetworkStats mUidSnapshot;
+        ArrayMap<String, NetworkIdentitySet> mActiveIfaces;
+        ArrayMap<String, NetworkIdentitySet> mActiveUidIfaces;
+        long mCurrentTime;
+
+        StatsContext(NetworkStats xtSnapshot, NetworkStats uidSnapshot,
+                ArrayMap<String, NetworkIdentitySet> activeIfaces,
+                ArrayMap<String, NetworkIdentitySet> activeUidIfaces,
+                long currentTime) {
+            mXtSnapshot = xtSnapshot;
+            mUidSnapshot = uidSnapshot;
+            mActiveIfaces = activeIfaces;
+            mActiveUidIfaces = activeUidIfaces;
+            mCurrentTime = currentTime;
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsRecorder.java b/service-t/src/com/android/server/net/NetworkStatsRecorder.java
new file mode 100644
index 0000000..f62765d
--- /dev/null
+++ b/service-t/src/com/android/server/net/NetworkStatsRecorder.java
@@ -0,0 +1,507 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.TrafficStats.KB_IN_BYTES;
+import static android.net.TrafficStats.MB_IN_BYTES;
+import static android.text.format.DateUtils.YEAR_IN_MILLIS;
+
+import android.net.NetworkIdentitySet;
+import android.net.NetworkStats;
+import android.net.NetworkStats.NonMonotonicObserver;
+import android.net.NetworkStatsAccess;
+import android.net.NetworkStatsCollection;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.TrafficStats;
+import android.os.Binder;
+import android.os.DropBoxManager;
+import android.service.NetworkStatsRecorderProto;
+import android.util.IndentingPrintWriter;
+import android.util.Log;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.internal.util.FileRotator;
+import com.android.net.module.util.NetworkStatsUtils;
+
+import libcore.io.IoUtils;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+import java.lang.ref.WeakReference;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Objects;
+
+/**
+ * Logic to record deltas between periodic {@link NetworkStats} snapshots into
+ * {@link NetworkStatsHistory} that belong to {@link NetworkStatsCollection}.
+ * Keeps pending changes in memory until they pass a specific threshold, in
+ * bytes. Uses {@link FileRotator} for persistence logic if present.
+ * <p>
+ * Not inherently thread safe.
+ */
+public class NetworkStatsRecorder {
+    private static final String TAG = "NetworkStatsRecorder";
+    private static final boolean LOGD = false;
+    private static final boolean LOGV = false;
+
+    private static final String TAG_NETSTATS_DUMP = "netstats_dump";
+
+    /** Dump before deleting in {@link #recoverFromWtf()}. */
+    private static final boolean DUMP_BEFORE_DELETE = true;
+
+    private final FileRotator mRotator;
+    private final NonMonotonicObserver<String> mObserver;
+    private final DropBoxManager mDropBox;
+    private final String mCookie;
+
+    private final long mBucketDuration;
+    private final boolean mOnlyTags;
+
+    private long mPersistThresholdBytes = 2 * MB_IN_BYTES;
+    private NetworkStats mLastSnapshot;
+
+    private final NetworkStatsCollection mPending;
+    private final NetworkStatsCollection mSinceBoot;
+
+    private final CombiningRewriter mPendingRewriter;
+
+    private WeakReference<NetworkStatsCollection> mComplete;
+
+    /**
+     * Non-persisted recorder, with only one bucket. Used by {@link NetworkStatsObservers}.
+     */
+    public NetworkStatsRecorder() {
+        mRotator = null;
+        mObserver = null;
+        mDropBox = null;
+        mCookie = null;
+
+        // set the bucket big enough to have all data in one bucket, but allow some
+        // slack to avoid overflow
+        mBucketDuration = YEAR_IN_MILLIS;
+        mOnlyTags = false;
+
+        mPending = null;
+        mSinceBoot = new NetworkStatsCollection(mBucketDuration);
+
+        mPendingRewriter = null;
+    }
+
+    /**
+     * Persisted recorder.
+     */
+    public NetworkStatsRecorder(FileRotator rotator, NonMonotonicObserver<String> observer,
+            DropBoxManager dropBox, String cookie, long bucketDuration, boolean onlyTags) {
+        mRotator = Objects.requireNonNull(rotator, "missing FileRotator");
+        mObserver = Objects.requireNonNull(observer, "missing NonMonotonicObserver");
+        mDropBox = Objects.requireNonNull(dropBox, "missing DropBoxManager");
+        mCookie = cookie;
+
+        mBucketDuration = bucketDuration;
+        mOnlyTags = onlyTags;
+
+        mPending = new NetworkStatsCollection(bucketDuration);
+        mSinceBoot = new NetworkStatsCollection(bucketDuration);
+
+        mPendingRewriter = new CombiningRewriter(mPending);
+    }
+
+    public void setPersistThreshold(long thresholdBytes) {
+        if (LOGV) Log.v(TAG, "setPersistThreshold() with " + thresholdBytes);
+        mPersistThresholdBytes = NetworkStatsUtils.constrain(
+                thresholdBytes, 1 * KB_IN_BYTES, 100 * MB_IN_BYTES);
+    }
+
+    public void resetLocked() {
+        mLastSnapshot = null;
+        if (mPending != null) {
+            mPending.reset();
+        }
+        if (mSinceBoot != null) {
+            mSinceBoot.reset();
+        }
+        if (mComplete != null) {
+            mComplete.clear();
+        }
+    }
+
+    public NetworkStats.Entry getTotalSinceBootLocked(NetworkTemplate template) {
+        return mSinceBoot.getSummary(template, Long.MIN_VALUE, Long.MAX_VALUE,
+                NetworkStatsAccess.Level.DEVICE, Binder.getCallingUid()).getTotal(null);
+    }
+
+    public NetworkStatsCollection getSinceBoot() {
+        return mSinceBoot;
+    }
+
+    /**
+     * Load complete history represented by {@link FileRotator}. Caches
+     * internally as a {@link WeakReference}, and updated with future
+     * {@link #recordSnapshotLocked(NetworkStats, Map, long)} snapshots as long
+     * as reference is valid.
+     */
+    public NetworkStatsCollection getOrLoadCompleteLocked() {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+        NetworkStatsCollection res = mComplete != null ? mComplete.get() : null;
+        if (res == null) {
+            res = loadLocked(Long.MIN_VALUE, Long.MAX_VALUE);
+            mComplete = new WeakReference<NetworkStatsCollection>(res);
+        }
+        return res;
+    }
+
+    public NetworkStatsCollection getOrLoadPartialLocked(long start, long end) {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+        NetworkStatsCollection res = mComplete != null ? mComplete.get() : null;
+        if (res == null) {
+            res = loadLocked(start, end);
+        }
+        return res;
+    }
+
+    private NetworkStatsCollection loadLocked(long start, long end) {
+        if (LOGD) Log.d(TAG, "loadLocked() reading from disk for " + mCookie);
+        final NetworkStatsCollection res = new NetworkStatsCollection(mBucketDuration);
+        try {
+            mRotator.readMatching(res, start, end);
+            res.recordCollection(mPending);
+        } catch (IOException e) {
+            Log.wtf(TAG, "problem completely reading network stats", e);
+            recoverFromWtf();
+        } catch (OutOfMemoryError e) {
+            Log.wtf(TAG, "problem completely reading network stats", e);
+            recoverFromWtf();
+        }
+        return res;
+    }
+
+    /**
+     * Record any delta that occurred since last {@link NetworkStats} snapshot, using the given
+     * {@link Map} to identify network interfaces. First snapshot is considered bootstrap, and is
+     * not counted as delta.
+     */
+    public void recordSnapshotLocked(NetworkStats snapshot,
+            Map<String, NetworkIdentitySet> ifaceIdent, long currentTimeMillis) {
+        final HashSet<String> unknownIfaces = new HashSet<>();
+
+        // skip recording when snapshot missing
+        if (snapshot == null) return;
+
+        // assume first snapshot is bootstrap and don't record
+        if (mLastSnapshot == null) {
+            mLastSnapshot = snapshot;
+            return;
+        }
+
+        final NetworkStatsCollection complete = mComplete != null ? mComplete.get() : null;
+
+        final NetworkStats delta = NetworkStats.subtract(
+                snapshot, mLastSnapshot, mObserver, mCookie);
+        final long end = currentTimeMillis;
+        final long start = end - delta.getElapsedRealtime();
+
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < delta.size(); i++) {
+            entry = delta.getValues(i, entry);
+
+            // As a last-ditch check, report any negative values and
+            // clamp them so recording below doesn't croak.
+            if (entry.isNegative()) {
+                if (mObserver != null) {
+                    mObserver.foundNonMonotonic(delta, i, mCookie);
+                }
+                entry.rxBytes = Math.max(entry.rxBytes, 0);
+                entry.rxPackets = Math.max(entry.rxPackets, 0);
+                entry.txBytes = Math.max(entry.txBytes, 0);
+                entry.txPackets = Math.max(entry.txPackets, 0);
+                entry.operations = Math.max(entry.operations, 0);
+            }
+
+            final NetworkIdentitySet ident = ifaceIdent.get(entry.iface);
+            if (ident == null) {
+                unknownIfaces.add(entry.iface);
+                continue;
+            }
+
+            // skip when no delta occurred
+            if (entry.isEmpty()) continue;
+
+            // only record tag data when requested
+            if ((entry.tag == TAG_NONE) != mOnlyTags) {
+                if (mPending != null) {
+                    mPending.recordData(ident, entry.uid, entry.set, entry.tag, start, end, entry);
+                }
+
+                // also record against boot stats when present
+                if (mSinceBoot != null) {
+                    mSinceBoot.recordData(ident, entry.uid, entry.set, entry.tag, start, end, entry);
+                }
+
+                // also record against complete dataset when present
+                if (complete != null) {
+                    complete.recordData(ident, entry.uid, entry.set, entry.tag, start, end, entry);
+                }
+            }
+        }
+
+        mLastSnapshot = snapshot;
+
+        if (LOGV && unknownIfaces.size() > 0) {
+            Log.w(TAG, "unknown interfaces " + unknownIfaces + ", ignoring those stats");
+        }
+    }
+
+    /**
+     * Consider persisting any pending deltas, if they are beyond
+     * {@link #mPersistThresholdBytes}.
+     */
+    public void maybePersistLocked(long currentTimeMillis) {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+        final long pendingBytes = mPending.getTotalBytes();
+        if (pendingBytes >= mPersistThresholdBytes) {
+            forcePersistLocked(currentTimeMillis);
+        } else {
+            mRotator.maybeRotate(currentTimeMillis);
+        }
+    }
+
+    /**
+     * Force persisting any pending deltas.
+     */
+    public void forcePersistLocked(long currentTimeMillis) {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+        if (mPending.isDirty()) {
+            if (LOGD) Log.d(TAG, "forcePersistLocked() writing for " + mCookie);
+            try {
+                mRotator.rewriteActive(mPendingRewriter, currentTimeMillis);
+                mRotator.maybeRotate(currentTimeMillis);
+                mPending.reset();
+            } catch (IOException e) {
+                Log.wtf(TAG, "problem persisting pending stats", e);
+                recoverFromWtf();
+            } catch (OutOfMemoryError e) {
+                Log.wtf(TAG, "problem persisting pending stats", e);
+                recoverFromWtf();
+            }
+        }
+    }
+
+    /**
+     * Remove the given UID from all {@link FileRotator} history, migrating it
+     * to {@link TrafficStats#UID_REMOVED}.
+     */
+    public void removeUidsLocked(int[] uids) {
+        if (mRotator != null) {
+            try {
+                // Rewrite all persisted data to migrate UID stats
+                mRotator.rewriteAll(new RemoveUidRewriter(mBucketDuration, uids));
+            } catch (IOException e) {
+                Log.wtf(TAG, "problem removing UIDs " + Arrays.toString(uids), e);
+                recoverFromWtf();
+            } catch (OutOfMemoryError e) {
+                Log.wtf(TAG, "problem removing UIDs " + Arrays.toString(uids), e);
+                recoverFromWtf();
+            }
+        }
+
+        // Remove any pending stats
+        if (mPending != null) {
+            mPending.removeUids(uids);
+        }
+        if (mSinceBoot != null) {
+            mSinceBoot.removeUids(uids);
+        }
+
+        // Clear UID from current stats snapshot
+        if (mLastSnapshot != null) {
+            mLastSnapshot.removeUids(uids);
+        }
+
+        final NetworkStatsCollection complete = mComplete != null ? mComplete.get() : null;
+        if (complete != null) {
+            complete.removeUids(uids);
+        }
+    }
+
+    /**
+     * Rewriter that will combine current {@link NetworkStatsCollection} values
+     * with anything read from disk, and write combined set to disk. Clears the
+     * original {@link NetworkStatsCollection} when finished writing.
+     */
+    private static class CombiningRewriter implements FileRotator.Rewriter {
+        private final NetworkStatsCollection mCollection;
+
+        public CombiningRewriter(NetworkStatsCollection collection) {
+            mCollection = Objects.requireNonNull(collection, "missing NetworkStatsCollection");
+        }
+
+        @Override
+        public void reset() {
+            // ignored
+        }
+
+        @Override
+        public void read(InputStream in) throws IOException {
+            mCollection.read(in);
+        }
+
+        @Override
+        public boolean shouldWrite() {
+            return true;
+        }
+
+        @Override
+        public void write(OutputStream out) throws IOException {
+            mCollection.write(out);
+            mCollection.reset();
+        }
+    }
+
+    /**
+     * Rewriter that will remove any {@link NetworkStatsHistory} attributed to
+     * the requested UID, only writing data back when modified.
+     */
+    public static class RemoveUidRewriter implements FileRotator.Rewriter {
+        private final NetworkStatsCollection mTemp;
+        private final int[] mUids;
+
+        public RemoveUidRewriter(long bucketDuration, int[] uids) {
+            mTemp = new NetworkStatsCollection(bucketDuration);
+            mUids = uids;
+        }
+
+        @Override
+        public void reset() {
+            mTemp.reset();
+        }
+
+        @Override
+        public void read(InputStream in) throws IOException {
+            mTemp.read(in);
+            mTemp.clearDirty();
+            mTemp.removeUids(mUids);
+        }
+
+        @Override
+        public boolean shouldWrite() {
+            return mTemp.isDirty();
+        }
+
+        @Override
+        public void write(OutputStream out) throws IOException {
+            mTemp.write(out);
+        }
+    }
+
+    public void importLegacyNetworkLocked(File file) throws IOException {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+
+        // legacy file still exists; start empty to avoid double importing
+        mRotator.deleteAll();
+
+        final NetworkStatsCollection collection = new NetworkStatsCollection(mBucketDuration);
+        collection.readLegacyNetwork(file);
+
+        final long startMillis = collection.getStartMillis();
+        final long endMillis = collection.getEndMillis();
+
+        if (!collection.isEmpty()) {
+            // process legacy data, creating active file at starting time, then
+            // using end time to possibly trigger rotation.
+            mRotator.rewriteActive(new CombiningRewriter(collection), startMillis);
+            mRotator.maybeRotate(endMillis);
+        }
+    }
+
+    public void importLegacyUidLocked(File file) throws IOException {
+        Objects.requireNonNull(mRotator, "missing FileRotator");
+
+        // legacy file still exists; start empty to avoid double importing
+        mRotator.deleteAll();
+
+        final NetworkStatsCollection collection = new NetworkStatsCollection(mBucketDuration);
+        collection.readLegacyUid(file, mOnlyTags);
+
+        final long startMillis = collection.getStartMillis();
+        final long endMillis = collection.getEndMillis();
+
+        if (!collection.isEmpty()) {
+            // process legacy data, creating active file at starting time, then
+            // using end time to possibly trigger rotation.
+            mRotator.rewriteActive(new CombiningRewriter(collection), startMillis);
+            mRotator.maybeRotate(endMillis);
+        }
+    }
+
+    public void dumpLocked(IndentingPrintWriter pw, boolean fullHistory) {
+        if (mPending != null) {
+            pw.print("Pending bytes: "); pw.println(mPending.getTotalBytes());
+        }
+        if (fullHistory) {
+            pw.println("Complete history:");
+            getOrLoadCompleteLocked().dump(pw);
+        } else {
+            pw.println("History since boot:");
+            mSinceBoot.dump(pw);
+        }
+    }
+
+    public void dumpDebugLocked(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+        if (mPending != null) {
+            proto.write(NetworkStatsRecorderProto.PENDING_TOTAL_BYTES,
+                    mPending.getTotalBytes());
+        }
+        getOrLoadCompleteLocked().dumpDebug(proto,
+                NetworkStatsRecorderProto.COMPLETE_HISTORY);
+        proto.end(start);
+    }
+
+    public void dumpCheckin(PrintWriter pw, long start, long end) {
+        // Only load and dump stats from the requested window
+        getOrLoadPartialLocked(start, end).dumpCheckin(pw, start, end);
+    }
+
+    /**
+     * Recover from {@link FileRotator} failure by dumping state to
+     * {@link DropBoxManager} and deleting contents.
+     */
+    private void recoverFromWtf() {
+        if (DUMP_BEFORE_DELETE) {
+            final ByteArrayOutputStream os = new ByteArrayOutputStream();
+            try {
+                mRotator.dumpAll(os);
+            } catch (IOException e) {
+                // ignore partial contents
+                os.reset();
+            } finally {
+                IoUtils.closeQuietly(os);
+            }
+            mDropBox.addData(TAG_NETSTATS_DUMP, os.toByteArray(), 0);
+        }
+
+        mRotator.deleteAll();
+    }
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
new file mode 100644
index 0000000..e3794e4
--- /dev/null
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -0,0 +1,2528 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static android.Manifest.permission.NETWORK_STATS_PROVIDER;
+import static android.Manifest.permission.READ_NETWORK_USAGE_HISTORY;
+import static android.Manifest.permission.UPDATE_DEVICE_STATS;
+import static android.app.usage.NetworkStatsManager.PREFIX_DEV;
+import static android.content.Intent.ACTION_SHUTDOWN;
+import static android.content.Intent.ACTION_UID_REMOVED;
+import static android.content.Intent.ACTION_USER_REMOVED;
+import static android.content.Intent.EXTRA_UID;
+import static android.content.pm.PackageManager.PERMISSION_GRANTED;
+import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
+import static android.net.NetworkStats.DEFAULT_NETWORK_ALL;
+import static android.net.NetworkStats.IFACE_ALL;
+import static android.net.NetworkStats.IFACE_VT;
+import static android.net.NetworkStats.INTERFACES_ALL;
+import static android.net.NetworkStats.METERED_ALL;
+import static android.net.NetworkStats.ROAMING_ALL;
+import static android.net.NetworkStats.SET_ALL;
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.SET_FOREGROUND;
+import static android.net.NetworkStats.STATS_PER_IFACE;
+import static android.net.NetworkStats.STATS_PER_UID;
+import static android.net.NetworkStats.TAG_ALL;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.NetworkStats.UID_ALL;
+import static android.net.NetworkStatsHistory.FIELD_ALL;
+import static android.net.NetworkTemplate.buildTemplateMobileWildcard;
+import static android.net.NetworkTemplate.buildTemplateWifiWildcard;
+import static android.net.TrafficStats.KB_IN_BYTES;
+import static android.net.TrafficStats.MB_IN_BYTES;
+import static android.net.TrafficStats.UID_TETHERING;
+import static android.net.TrafficStats.UNSUPPORTED;
+import static android.net.netstats.NetworkStatsDataMigrationUtils.PREFIX_UID;
+import static android.net.netstats.NetworkStatsDataMigrationUtils.PREFIX_UID_TAG;
+import static android.net.netstats.NetworkStatsDataMigrationUtils.PREFIX_XT;
+import static android.os.Trace.TRACE_TAG_NETWORK;
+import static android.system.OsConstants.ENOENT;
+import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
+import static android.text.format.DateUtils.DAY_IN_MILLIS;
+import static android.text.format.DateUtils.HOUR_IN_MILLIS;
+import static android.text.format.DateUtils.MINUTE_IN_MILLIS;
+import static android.text.format.DateUtils.SECOND_IN_MILLIS;
+
+import static com.android.net.module.util.NetworkCapabilitiesUtils.getDisplayTransport;
+import static com.android.net.module.util.NetworkStatsUtils.LIMIT_GLOBAL_ALERT;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.TargetApi;
+import android.app.AlarmManager;
+import android.app.PendingIntent;
+import android.app.usage.NetworkStatsManager;
+import android.content.BroadcastReceiver;
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.database.ContentObserver;
+import android.net.DataUsageRequest;
+import android.net.INetd;
+import android.net.INetworkStatsService;
+import android.net.INetworkStatsSession;
+import android.net.Network;
+import android.net.NetworkCapabilities;
+import android.net.NetworkIdentity;
+import android.net.NetworkIdentitySet;
+import android.net.NetworkPolicyManager;
+import android.net.NetworkSpecifier;
+import android.net.NetworkStack;
+import android.net.NetworkStateSnapshot;
+import android.net.NetworkStats;
+import android.net.NetworkStats.NonMonotonicObserver;
+import android.net.NetworkStatsAccess;
+import android.net.NetworkStatsCollection;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.TelephonyNetworkSpecifier;
+import android.net.TetherStatsParcel;
+import android.net.TetheringManager;
+import android.net.TrafficStats;
+import android.net.UnderlyingNetworkInfo;
+import android.net.Uri;
+import android.net.netstats.IUsageCallback;
+import android.net.netstats.provider.INetworkStatsProvider;
+import android.net.netstats.provider.INetworkStatsProviderCallback;
+import android.net.netstats.provider.NetworkStatsProvider;
+import android.os.Binder;
+import android.os.Build;
+import android.os.DropBoxManager;
+import android.os.Environment;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.IBinder;
+import android.os.Looper;
+import android.os.Message;
+import android.os.PowerManager;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.os.SystemClock;
+import android.os.Trace;
+import android.os.UserHandle;
+import android.provider.Settings;
+import android.provider.Settings.Global;
+import android.service.NetworkInterfaceProto;
+import android.service.NetworkStatsServiceDumpProto;
+import android.system.ErrnoException;
+import android.telephony.PhoneStateListener;
+import android.telephony.SubscriptionPlan;
+import android.text.TextUtils;
+import android.text.format.DateUtils;
+import android.util.ArrayMap;
+import android.util.ArraySet;
+import android.util.EventLog;
+import android.util.IndentingPrintWriter;
+import android.util.Log;
+import android.util.SparseIntArray;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.FileRotator;
+import com.android.net.module.util.BaseNetdUnsolicitedEventListener;
+import com.android.net.module.util.BestClock;
+import com.android.net.module.util.BinderUtils;
+import com.android.net.module.util.BpfMap;
+import com.android.net.module.util.CollectionUtils;
+import com.android.net.module.util.IBpfMap;
+import com.android.net.module.util.LocationPermissionChecker;
+import com.android.net.module.util.NetworkStatsUtils;
+import com.android.net.module.util.PermissionUtils;
+import com.android.net.module.util.Struct.U32;
+import com.android.net.module.util.Struct.U8;
+
+import java.io.File;
+import java.io.FileDescriptor;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.time.Clock;
+import java.time.ZoneOffset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Semaphore;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Collect and persist detailed network statistics, and provide this data to
+ * other system services.
+ */
+@TargetApi(Build.VERSION_CODES.TIRAMISU)
+public class NetworkStatsService extends INetworkStatsService.Stub {
+    static {
+        System.loadLibrary("service-connectivity");
+    }
+
+    static final String TAG = "NetworkStats";
+    static final boolean LOGD = Log.isLoggable(TAG, Log.DEBUG);
+    static final boolean LOGV = Log.isLoggable(TAG, Log.VERBOSE);
+
+    // Perform polling and persist all (FLAG_PERSIST_ALL).
+    private static final int MSG_PERFORM_POLL = 1;
+    // Perform polling, persist network, and register the global alert again.
+    private static final int MSG_PERFORM_POLL_REGISTER_ALERT = 2;
+    private static final int MSG_NOTIFY_NETWORK_STATUS = 3;
+    // A message for broadcasting ACTION_NETWORK_STATS_UPDATED in handler thread to prevent
+    // deadlock.
+    private static final int MSG_BROADCAST_NETWORK_STATS_UPDATED = 4;
+
+    /** Flags to control detail level of poll event. */
+    private static final int FLAG_PERSIST_NETWORK = 0x1;
+    private static final int FLAG_PERSIST_UID = 0x2;
+    private static final int FLAG_PERSIST_ALL = FLAG_PERSIST_NETWORK | FLAG_PERSIST_UID;
+    private static final int FLAG_PERSIST_FORCE = 0x100;
+
+    /**
+     * When global alert quota is high, wait for this delay before processing each polling,
+     * and do not schedule further polls once there is already one queued.
+     * This avoids firing the global alert too often on devices with high transfer speeds and
+     * high quota.
+     */
+    private static final int DEFAULT_PERFORM_POLL_DELAY_MS = 1000;
+
+    private static final String TAG_NETSTATS_ERROR = "netstats_error";
+
+    /**
+     * EventLog tags used when logging into the event log. Note the values must be sync with
+     * frameworks/base/services/core/java/com/android/server/EventLogTags.logtags to get correct
+     * name translation.
+      */
+    private static final int LOG_TAG_NETSTATS_MOBILE_SAMPLE = 51100;
+    private static final int LOG_TAG_NETSTATS_WIFI_SAMPLE = 51101;
+
+    // TODO: Replace the hardcoded string and move it into ConnectivitySettingsManager.
+    private static final String NETSTATS_COMBINE_SUBTYPE_ENABLED =
+            "netstats_combine_subtype_enabled";
+
+    // This is current path but may be changed soon.
+    private static final String UID_COUNTERSET_MAP_PATH =
+            "/sys/fs/bpf/map_netd_uid_counterset_map";
+    private static final String COOKIE_TAG_MAP_PATH =
+            "/sys/fs/bpf/map_netd_cookie_tag_map";
+    private static final String APP_UID_STATS_MAP_PATH =
+            "/sys/fs/bpf/map_netd_app_uid_stats_map";
+    private static final String STATS_MAP_A_PATH =
+            "/sys/fs/bpf/map_netd_stats_map_A";
+    private static final String STATS_MAP_B_PATH =
+            "/sys/fs/bpf/map_netd_stats_map_B";
+
+    private final Context mContext;
+    private final NetworkStatsFactory mStatsFactory;
+    private final AlarmManager mAlarmManager;
+    private final Clock mClock;
+    private final NetworkStatsSettings mSettings;
+    private final NetworkStatsObservers mStatsObservers;
+
+    private final File mSystemDir;
+    private final File mBaseDir;
+
+    private final PowerManager.WakeLock mWakeLock;
+
+    private final ContentObserver mContentObserver;
+    private final ContentResolver mContentResolver;
+
+    protected INetd mNetd;
+    private final AlertObserver mAlertObserver = new AlertObserver();
+
+    @VisibleForTesting
+    public static final String ACTION_NETWORK_STATS_POLL =
+            "com.android.server.action.NETWORK_STATS_POLL";
+    public static final String ACTION_NETWORK_STATS_UPDATED =
+            "com.android.server.action.NETWORK_STATS_UPDATED";
+
+    private PendingIntent mPollIntent;
+
+    /**
+     * Settings that can be changed externally.
+     */
+    public interface NetworkStatsSettings {
+        long getPollInterval();
+        long getPollDelay();
+        boolean getSampleEnabled();
+        boolean getAugmentEnabled();
+        /**
+         * When enabled, all mobile data is reported under {@link NetworkTemplate#NETWORK_TYPE_ALL}.
+         * When disabled, mobile data is broken down by a granular ratType representative of the
+         * actual ratType. {@see android.app.usage.NetworkStatsManager#getCollapsedRatType}.
+         * Enabling this decreases the level of detail but saves performance, disk space and
+         * amount of data logged.
+         */
+        boolean getCombineSubtypeEnabled();
+
+        class Config {
+            public final long bucketDuration;
+            public final long rotateAgeMillis;
+            public final long deleteAgeMillis;
+
+            public Config(long bucketDuration, long rotateAgeMillis, long deleteAgeMillis) {
+                this.bucketDuration = bucketDuration;
+                this.rotateAgeMillis = rotateAgeMillis;
+                this.deleteAgeMillis = deleteAgeMillis;
+            }
+        }
+
+        Config getDevConfig();
+        Config getXtConfig();
+        Config getUidConfig();
+        Config getUidTagConfig();
+
+        long getGlobalAlertBytes(long def);
+        long getDevPersistBytes(long def);
+        long getXtPersistBytes(long def);
+        long getUidPersistBytes(long def);
+        long getUidTagPersistBytes(long def);
+    }
+
+    private final Object mStatsLock = new Object();
+
+    /** Set of currently active ifaces. */
+    @GuardedBy("mStatsLock")
+    private final ArrayMap<String, NetworkIdentitySet> mActiveIfaces = new ArrayMap<>();
+
+    /** Set of currently active ifaces for UID stats. */
+    @GuardedBy("mStatsLock")
+    private final ArrayMap<String, NetworkIdentitySet> mActiveUidIfaces = new ArrayMap<>();
+
+    /** Current default active iface. */
+    @GuardedBy("mStatsLock")
+    private String mActiveIface;
+
+    /** Set of any ifaces associated with mobile networks since boot. */
+    private volatile String[] mMobileIfaces = new String[0];
+
+    /** Set of any ifaces associated with wifi networks since boot. */
+    private volatile String[] mWifiIfaces = new String[0];
+
+    /** Set of all ifaces currently used by traffic that does not explicitly specify a Network. */
+    @GuardedBy("mStatsLock")
+    private Network[] mDefaultNetworks = new Network[0];
+
+    /** Last states of all networks sent from ConnectivityService. */
+    @GuardedBy("mStatsLock")
+    @Nullable
+    private NetworkStateSnapshot[] mLastNetworkStateSnapshots = null;
+
+    private final DropBoxNonMonotonicObserver mNonMonotonicObserver =
+            new DropBoxNonMonotonicObserver();
+
+    private static final int MAX_STATS_PROVIDER_POLL_WAIT_TIME_MS = 100;
+    private final CopyOnWriteArrayList<NetworkStatsProviderCallbackImpl> mStatsProviderCbList =
+            new CopyOnWriteArrayList<>();
+    /** Semaphore used to wait for stats provider to respond to request stats update. */
+    private final Semaphore mStatsProviderSem = new Semaphore(0, true);
+
+    @GuardedBy("mStatsLock")
+    private NetworkStatsRecorder mDevRecorder;
+    @GuardedBy("mStatsLock")
+    private NetworkStatsRecorder mXtRecorder;
+    @GuardedBy("mStatsLock")
+    private NetworkStatsRecorder mUidRecorder;
+    @GuardedBy("mStatsLock")
+    private NetworkStatsRecorder mUidTagRecorder;
+
+    /** Cached {@link #mXtRecorder} stats. */
+    @GuardedBy("mStatsLock")
+    private NetworkStatsCollection mXtStatsCached;
+
+    /**
+     * Current counter sets for each UID.
+     * TODO: maybe remove mActiveUidCounterSet and read UidCouneterSet value from mUidCounterSetMap
+     * directly ? But if mActiveUidCounterSet would be accessed very frequently, maybe keep
+     * mActiveUidCounterSet to avoid accessing kernel too frequently.
+     */
+    private SparseIntArray mActiveUidCounterSet = new SparseIntArray();
+    private final IBpfMap<U32, U8> mUidCounterSetMap;
+    private final IBpfMap<CookieTagMapKey, CookieTagMapValue> mCookieTagMap;
+    private final IBpfMap<StatsMapKey, StatsMapValue> mStatsMapA;
+    private final IBpfMap<StatsMapKey, StatsMapValue> mStatsMapB;
+    private final IBpfMap<UidStatsMapKey, StatsMapValue> mAppUidStatsMap;
+
+    /** Data layer operation counters for splicing into other structures. */
+    private NetworkStats mUidOperations = new NetworkStats(0L, 10);
+
+    @NonNull
+    private final Handler mHandler;
+
+    private volatile boolean mSystemReady;
+    private long mPersistThreshold = 2 * MB_IN_BYTES;
+    private long mGlobalAlertBytes;
+
+    private static final long POLL_RATE_LIMIT_MS = 15_000;
+
+    private long mLastStatsSessionPoll;
+
+    /** Map from UID to number of opened sessions */
+    @GuardedBy("mOpenSessionCallsPerUid")
+    private final SparseIntArray mOpenSessionCallsPerUid = new SparseIntArray();
+
+    private final static int DUMP_STATS_SESSION_COUNT = 20;
+
+    @NonNull
+    private final Dependencies mDeps;
+
+    @NonNull
+    private final NetworkStatsSubscriptionsMonitor mNetworkStatsSubscriptionsMonitor;
+
+    @NonNull
+    private final LocationPermissionChecker mLocationPermissionChecker;
+
+    @NonNull
+    private final BpfInterfaceMapUpdater mInterfaceMapUpdater;
+
+    private static @NonNull File getDefaultSystemDir() {
+        return new File(Environment.getDataDirectory(), "system");
+    }
+
+    private static @NonNull File getDefaultBaseDir() {
+        File baseDir = new File(getDefaultSystemDir(), "netstats");
+        baseDir.mkdirs();
+        return baseDir;
+    }
+
+    private static @NonNull Clock getDefaultClock() {
+        return new BestClock(ZoneOffset.UTC, SystemClock.currentNetworkTimeClock(),
+                Clock.systemUTC());
+    }
+
+    private final class NetworkStatsHandler extends Handler {
+        NetworkStatsHandler(@NonNull Looper looper) {
+            super(looper);
+        }
+
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+                case MSG_PERFORM_POLL: {
+                    performPoll(FLAG_PERSIST_ALL);
+                    break;
+                }
+                case MSG_NOTIFY_NETWORK_STATUS: {
+                    // If no cached states, ignore.
+                    if (mLastNetworkStateSnapshots == null) break;
+                    // TODO (b/181642673): Protect mDefaultNetworks from concurrent accessing.
+                    handleNotifyNetworkStatus(
+                            mDefaultNetworks, mLastNetworkStateSnapshots, mActiveIface);
+                    break;
+                }
+                case MSG_PERFORM_POLL_REGISTER_ALERT: {
+                    performPoll(FLAG_PERSIST_NETWORK);
+                    registerGlobalAlert();
+                    break;
+                }
+                case MSG_BROADCAST_NETWORK_STATS_UPDATED: {
+                    final Intent updatedIntent = new Intent(ACTION_NETWORK_STATS_UPDATED);
+                    updatedIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
+                    mContext.sendBroadcastAsUser(updatedIntent, UserHandle.ALL,
+                            READ_NETWORK_USAGE_HISTORY);
+                    break;
+                }
+            }
+        }
+    }
+
+    /** Creates a new NetworkStatsService */
+    public static NetworkStatsService create(Context context) {
+        AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
+        PowerManager powerManager = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
+        PowerManager.WakeLock wakeLock =
+                powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
+        final INetd netd = INetd.Stub.asInterface(
+                (IBinder) context.getSystemService(Context.NETD_SERVICE));
+        final NetworkStatsService service = new NetworkStatsService(context,
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
+                alarmManager, wakeLock, getDefaultClock(),
+                new DefaultNetworkStatsSettings(), new NetworkStatsFactory(context),
+                new NetworkStatsObservers(), getDefaultSystemDir(), getDefaultBaseDir(),
+                new Dependencies());
+
+        return service;
+    }
+
+    // This must not be called outside of tests, even within the same package, as this constructor
+    // does not register the local service. Use the create() helper above.
+    @VisibleForTesting
+    NetworkStatsService(Context context, INetd netd, AlarmManager alarmManager,
+            PowerManager.WakeLock wakeLock, Clock clock, NetworkStatsSettings settings,
+            NetworkStatsFactory factory, NetworkStatsObservers statsObservers, File systemDir,
+            File baseDir, @NonNull Dependencies deps) {
+        mContext = Objects.requireNonNull(context, "missing Context");
+        mNetd = Objects.requireNonNull(netd, "missing Netd");
+        mAlarmManager = Objects.requireNonNull(alarmManager, "missing AlarmManager");
+        mClock = Objects.requireNonNull(clock, "missing Clock");
+        mSettings = Objects.requireNonNull(settings, "missing NetworkStatsSettings");
+        mWakeLock = Objects.requireNonNull(wakeLock, "missing WakeLock");
+        mStatsFactory = Objects.requireNonNull(factory, "missing factory");
+        mStatsObservers = Objects.requireNonNull(statsObservers, "missing NetworkStatsObservers");
+        mSystemDir = Objects.requireNonNull(systemDir, "missing systemDir");
+        mBaseDir = Objects.requireNonNull(baseDir, "missing baseDir");
+        mDeps = Objects.requireNonNull(deps, "missing Dependencies");
+
+        final HandlerThread handlerThread = mDeps.makeHandlerThread();
+        handlerThread.start();
+        mHandler = new NetworkStatsHandler(handlerThread.getLooper());
+        mNetworkStatsSubscriptionsMonitor = deps.makeSubscriptionsMonitor(mContext,
+                (command) -> mHandler.post(command) , this);
+        mContentResolver = mContext.getContentResolver();
+        mContentObserver = mDeps.makeContentObserver(mHandler, mSettings,
+                mNetworkStatsSubscriptionsMonitor);
+        mLocationPermissionChecker = mDeps.makeLocationPermissionChecker(mContext);
+        mInterfaceMapUpdater = mDeps.makeBpfInterfaceMapUpdater(mContext, mHandler);
+        mInterfaceMapUpdater.start();
+        mUidCounterSetMap = mDeps.getUidCounterSetMap();
+        mCookieTagMap = mDeps.getCookieTagMap();
+        mStatsMapA = mDeps.getStatsMapA();
+        mStatsMapB = mDeps.getStatsMapB();
+        mAppUidStatsMap = mDeps.getAppUidStatsMap();
+    }
+
+    /**
+     * Dependencies of NetworkStatsService, for injection in tests.
+     */
+    // TODO: Move more stuff into dependencies object.
+    @VisibleForTesting
+    public static class Dependencies {
+        /**
+         * Create a HandlerThread to use in NetworkStatsService.
+         */
+        @NonNull
+        public HandlerThread makeHandlerThread() {
+            return new HandlerThread(TAG);
+        }
+
+        /**
+         * Create a {@link NetworkStatsSubscriptionsMonitor}, can be used to monitor RAT change
+         * event in NetworkStatsService.
+         */
+        @NonNull
+        public NetworkStatsSubscriptionsMonitor makeSubscriptionsMonitor(@NonNull Context context,
+                @NonNull Executor executor, @NonNull NetworkStatsService service) {
+            // TODO: Update RatType passively in NSS, instead of querying into the monitor
+            //  when notifyNetworkStatus.
+            return new NetworkStatsSubscriptionsMonitor(context, executor,
+                    (subscriberId, type) -> service.handleOnCollapsedRatTypeChanged());
+        }
+
+        /**
+         * Create a ContentObserver instance which is used to observe settings changes,
+         * and dispatch onChange events on handler thread.
+         */
+        public @NonNull ContentObserver makeContentObserver(@NonNull Handler handler,
+                @NonNull NetworkStatsSettings settings,
+                @NonNull NetworkStatsSubscriptionsMonitor monitor) {
+            return new ContentObserver(handler) {
+                @Override
+                public void onChange(boolean selfChange, @NonNull Uri uri) {
+                    if (!settings.getCombineSubtypeEnabled()) {
+                        monitor.start();
+                    } else {
+                        monitor.stop();
+                    }
+                }
+            };
+        }
+
+        /**
+         * @see LocationPermissionChecker
+         */
+        public LocationPermissionChecker makeLocationPermissionChecker(final Context context) {
+            return new LocationPermissionChecker(context);
+        }
+
+        /** Create BpfInterfaceMapUpdater to update bpf interface map. */
+        @NonNull
+        public BpfInterfaceMapUpdater makeBpfInterfaceMapUpdater(
+                @NonNull Context ctx, @NonNull Handler handler) {
+            return new BpfInterfaceMapUpdater(ctx, handler);
+        }
+
+        /** Get counter sets map for each UID. */
+        public IBpfMap<U32, U8> getUidCounterSetMap() {
+            try {
+                return new BpfMap<U32, U8>(UID_COUNTERSET_MAP_PATH, BpfMap.BPF_F_RDWR,
+                        U32.class, U8.class);
+            } catch (ErrnoException e) {
+                Log.wtf(TAG, "Cannot open uid counter set map: " + e);
+                return null;
+            }
+        }
+
+        /** Gets the cookie tag map */
+        public IBpfMap<CookieTagMapKey, CookieTagMapValue> getCookieTagMap() {
+            try {
+                return new BpfMap<CookieTagMapKey, CookieTagMapValue>(COOKIE_TAG_MAP_PATH,
+                        BpfMap.BPF_F_RDWR, CookieTagMapKey.class, CookieTagMapValue.class);
+            } catch (ErrnoException e) {
+                Log.wtf(TAG, "Cannot open cookie tag map: " + e);
+                return null;
+            }
+        }
+
+        /** Gets stats map A */
+        public IBpfMap<StatsMapKey, StatsMapValue> getStatsMapA() {
+            try {
+                return new BpfMap<StatsMapKey, StatsMapValue>(STATS_MAP_A_PATH,
+                        BpfMap.BPF_F_RDWR, StatsMapKey.class, StatsMapValue.class);
+            } catch (ErrnoException e) {
+                Log.wtf(TAG, "Cannot open stats map A: " + e);
+                return null;
+            }
+        }
+
+        /** Gets stats map B */
+        public IBpfMap<StatsMapKey, StatsMapValue> getStatsMapB() {
+            try {
+                return new BpfMap<StatsMapKey, StatsMapValue>(STATS_MAP_B_PATH,
+                        BpfMap.BPF_F_RDWR, StatsMapKey.class, StatsMapValue.class);
+            } catch (ErrnoException e) {
+                Log.wtf(TAG, "Cannot open stats map B: " + e);
+                return null;
+            }
+        }
+
+        /** Gets the uid stats map */
+        public IBpfMap<UidStatsMapKey, StatsMapValue> getAppUidStatsMap() {
+            try {
+                return new BpfMap<UidStatsMapKey, StatsMapValue>(APP_UID_STATS_MAP_PATH,
+                        BpfMap.BPF_F_RDWR, UidStatsMapKey.class, StatsMapValue.class);
+            } catch (ErrnoException e) {
+                Log.wtf(TAG, "Cannot open app uid stats map: " + e);
+                return null;
+            }
+        }
+    }
+
+    /**
+     * Observer that watches for {@link INetdUnsolicitedEventListener} alerts.
+     */
+    @VisibleForTesting
+    public class AlertObserver extends BaseNetdUnsolicitedEventListener {
+        @Override
+        public void onQuotaLimitReached(@NonNull String alertName, @NonNull String ifName) {
+            PermissionUtils.enforceNetworkStackPermission(mContext);
+
+            if (LIMIT_GLOBAL_ALERT.equals(alertName)) {
+                // kick off background poll to collect network stats unless there is already
+                // such a call pending; UID stats are handled during normal polling interval.
+                if (!mHandler.hasMessages(MSG_PERFORM_POLL_REGISTER_ALERT)) {
+                    mHandler.sendEmptyMessageDelayed(MSG_PERFORM_POLL_REGISTER_ALERT,
+                            mSettings.getPollDelay());
+                }
+            }
+        }
+    }
+
+    public void systemReady() {
+        synchronized (mStatsLock) {
+            mSystemReady = true;
+
+            // create data recorders along with historical rotators
+            mDevRecorder = buildRecorder(PREFIX_DEV, mSettings.getDevConfig(), false);
+            mXtRecorder = buildRecorder(PREFIX_XT, mSettings.getXtConfig(), false);
+            mUidRecorder = buildRecorder(PREFIX_UID, mSettings.getUidConfig(), false);
+            mUidTagRecorder = buildRecorder(PREFIX_UID_TAG, mSettings.getUidTagConfig(), true);
+
+            updatePersistThresholdsLocked();
+
+            // upgrade any legacy stats, migrating them to rotated files
+            maybeUpgradeLegacyStatsLocked();
+
+            // read historical network stats from disk, since policy service
+            // might need them right away.
+            mXtStatsCached = mXtRecorder.getOrLoadCompleteLocked();
+
+            // bootstrap initial stats to prevent double-counting later
+            bootstrapStatsLocked();
+        }
+
+        // watch for tethering changes
+        final TetheringManager tetheringManager = mContext.getSystemService(TetheringManager.class);
+        tetheringManager.registerTetheringEventCallback(
+                (command) -> mHandler.post(command), mTetherListener);
+
+        // listen for periodic polling events
+        final IntentFilter pollFilter = new IntentFilter(ACTION_NETWORK_STATS_POLL);
+        mContext.registerReceiver(mPollReceiver, pollFilter, READ_NETWORK_USAGE_HISTORY, mHandler);
+
+        // listen for uid removal to clean stats
+        final IntentFilter removedFilter = new IntentFilter(ACTION_UID_REMOVED);
+        mContext.registerReceiver(mRemovedReceiver, removedFilter, null, mHandler);
+
+        // listen for user changes to clean stats
+        final IntentFilter userFilter = new IntentFilter(ACTION_USER_REMOVED);
+        mContext.registerReceiver(mUserReceiver, userFilter, null, mHandler);
+
+        // persist stats during clean shutdown
+        final IntentFilter shutdownFilter = new IntentFilter(ACTION_SHUTDOWN);
+        mContext.registerReceiver(mShutdownReceiver, shutdownFilter);
+
+        try {
+            mNetd.registerUnsolicitedEventListener(mAlertObserver);
+        } catch (RemoteException | ServiceSpecificException e) {
+            Log.wtf(TAG, "Error registering event listener :", e);
+        }
+
+        //  schedule periodic pall alarm based on {@link NetworkStatsSettings#getPollInterval()}.
+        final PendingIntent pollIntent =
+                PendingIntent.getBroadcast(mContext, 0, new Intent(ACTION_NETWORK_STATS_POLL),
+                        PendingIntent.FLAG_IMMUTABLE);
+
+        final long currentRealtime = SystemClock.elapsedRealtime();
+        mAlarmManager.setInexactRepeating(AlarmManager.ELAPSED_REALTIME, currentRealtime,
+                mSettings.getPollInterval(), pollIntent);
+
+        mContentResolver.registerContentObserver(Settings.Global
+                .getUriFor(NETSTATS_COMBINE_SUBTYPE_ENABLED),
+                        false /* notifyForDescendants */, mContentObserver);
+
+        // Post a runnable on handler thread to call onChange(). It's for getting current value of
+        // NETSTATS_COMBINE_SUBTYPE_ENABLED to decide start or stop monitoring RAT type changes.
+        mHandler.post(() -> mContentObserver.onChange(false, Settings.Global
+                .getUriFor(NETSTATS_COMBINE_SUBTYPE_ENABLED)));
+
+        registerGlobalAlert();
+    }
+
+    private NetworkStatsRecorder buildRecorder(
+            String prefix, NetworkStatsSettings.Config config, boolean includeTags) {
+        final DropBoxManager dropBox = (DropBoxManager) mContext.getSystemService(
+                Context.DROPBOX_SERVICE);
+        return new NetworkStatsRecorder(new FileRotator(
+                mBaseDir, prefix, config.rotateAgeMillis, config.deleteAgeMillis),
+                mNonMonotonicObserver, dropBox, prefix, config.bucketDuration, includeTags);
+    }
+
+    @GuardedBy("mStatsLock")
+    private void shutdownLocked() {
+        final TetheringManager tetheringManager = mContext.getSystemService(TetheringManager.class);
+        tetheringManager.unregisterTetheringEventCallback(mTetherListener);
+        mContext.unregisterReceiver(mPollReceiver);
+        mContext.unregisterReceiver(mRemovedReceiver);
+        mContext.unregisterReceiver(mUserReceiver);
+        mContext.unregisterReceiver(mShutdownReceiver);
+
+        if (!mSettings.getCombineSubtypeEnabled()) {
+            mNetworkStatsSubscriptionsMonitor.stop();
+        }
+
+        mContentResolver.unregisterContentObserver(mContentObserver);
+
+        final long currentTime = mClock.millis();
+
+        // persist any pending stats
+        mDevRecorder.forcePersistLocked(currentTime);
+        mXtRecorder.forcePersistLocked(currentTime);
+        mUidRecorder.forcePersistLocked(currentTime);
+        mUidTagRecorder.forcePersistLocked(currentTime);
+
+        mSystemReady = false;
+    }
+
+    @GuardedBy("mStatsLock")
+    private void maybeUpgradeLegacyStatsLocked() {
+        File file;
+        try {
+            file = new File(mSystemDir, "netstats.bin");
+            if (file.exists()) {
+                mDevRecorder.importLegacyNetworkLocked(file);
+                file.delete();
+            }
+
+            file = new File(mSystemDir, "netstats_xt.bin");
+            if (file.exists()) {
+                file.delete();
+            }
+
+            file = new File(mSystemDir, "netstats_uid.bin");
+            if (file.exists()) {
+                mUidRecorder.importLegacyUidLocked(file);
+                mUidTagRecorder.importLegacyUidLocked(file);
+                file.delete();
+            }
+        } catch (IOException e) {
+            Log.wtf(TAG, "problem during legacy upgrade", e);
+        } catch (OutOfMemoryError e) {
+            Log.wtf(TAG, "problem during legacy upgrade", e);
+        }
+    }
+
+    /**
+     * Register for a global alert that is delivered through {@link AlertObserver}
+     * or {@link NetworkStatsProviderCallback#onAlertReached()} once a threshold amount of data has
+     * been transferred.
+     */
+    private void registerGlobalAlert() {
+        try {
+            mNetd.bandwidthSetGlobalAlert(mGlobalAlertBytes);
+        } catch (IllegalStateException e) {
+            Log.w(TAG, "problem registering for global alert: " + e);
+        } catch (RemoteException e) {
+            // ignored; service lives in system_server
+        }
+        invokeForAllStatsProviderCallbacks((cb) -> cb.mProvider.onSetAlert(mGlobalAlertBytes));
+    }
+
+    @Override
+    public INetworkStatsSession openSession() {
+        return openSessionInternal(NetworkStatsManager.FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN, null);
+    }
+
+    @Override
+    public INetworkStatsSession openSessionForUsageStats(int flags, String callingPackage) {
+        return openSessionInternal(flags, callingPackage);
+    }
+
+    private boolean isRateLimitedForPoll(int callingUid) {
+        if (callingUid == android.os.Process.SYSTEM_UID) {
+            return false;
+        }
+
+        final long lastCallTime;
+        final long now = SystemClock.elapsedRealtime();
+        synchronized (mOpenSessionCallsPerUid) {
+            int calls = mOpenSessionCallsPerUid.get(callingUid, 0);
+            mOpenSessionCallsPerUid.put(callingUid, calls + 1);
+            lastCallTime = mLastStatsSessionPoll;
+            mLastStatsSessionPoll = now;
+        }
+
+        return now - lastCallTime < POLL_RATE_LIMIT_MS;
+    }
+
+    private int restrictFlagsForCaller(int flags) {
+        // All non-privileged callers are not allowed to turn off POLL_ON_OPEN.
+        final boolean isPrivileged = PermissionUtils.checkAnyPermissionOf(mContext,
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+                android.Manifest.permission.NETWORK_STACK);
+        if (!isPrivileged) {
+            flags |= NetworkStatsManager.FLAG_POLL_ON_OPEN;
+        }
+        // Non-system uids are rate limited for POLL_ON_OPEN.
+        final int callingUid = Binder.getCallingUid();
+        flags = isRateLimitedForPoll(callingUid)
+                ? flags & (~NetworkStatsManager.FLAG_POLL_ON_OPEN)
+                : flags;
+        return flags;
+    }
+
+    private INetworkStatsSession openSessionInternal(final int flags, final String callingPackage) {
+        final int restrictedFlags = restrictFlagsForCaller(flags);
+        if ((restrictedFlags & (NetworkStatsManager.FLAG_POLL_ON_OPEN
+                | NetworkStatsManager.FLAG_POLL_FORCE)) != 0) {
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                performPoll(FLAG_PERSIST_ALL);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        // return an IBinder which holds strong references to any loaded stats
+        // for its lifetime; when caller closes only weak references remain.
+
+        return new INetworkStatsSession.Stub() {
+            private final int mCallingUid = Binder.getCallingUid();
+            private final String mCallingPackage = callingPackage;
+            private final @NetworkStatsAccess.Level int mAccessLevel = checkAccessLevel(
+                    callingPackage);
+
+            private NetworkStatsCollection mUidComplete;
+            private NetworkStatsCollection mUidTagComplete;
+
+            private NetworkStatsCollection getUidComplete() {
+                synchronized (mStatsLock) {
+                    if (mUidComplete == null) {
+                        mUidComplete = mUidRecorder.getOrLoadCompleteLocked();
+                    }
+                    return mUidComplete;
+                }
+            }
+
+            private NetworkStatsCollection getUidTagComplete() {
+                synchronized (mStatsLock) {
+                    if (mUidTagComplete == null) {
+                        mUidTagComplete = mUidTagRecorder.getOrLoadCompleteLocked();
+                    }
+                    return mUidTagComplete;
+                }
+            }
+
+            @Override
+            public int[] getRelevantUids() {
+                return getUidComplete().getRelevantUids(mAccessLevel);
+            }
+
+            @Override
+            public NetworkStats getDeviceSummaryForNetwork(
+                    NetworkTemplate template, long start, long end) {
+                enforceTemplatePermissions(template, callingPackage);
+                return internalGetSummaryForNetwork(template, restrictedFlags, start, end,
+                        mAccessLevel, mCallingUid);
+            }
+
+            @Override
+            public NetworkStats getSummaryForNetwork(
+                    NetworkTemplate template, long start, long end) {
+                enforceTemplatePermissions(template, callingPackage);
+                return internalGetSummaryForNetwork(template, restrictedFlags, start, end,
+                        mAccessLevel, mCallingUid);
+            }
+
+            // TODO: Remove this after all callers are removed.
+            @Override
+            public NetworkStatsHistory getHistoryForNetwork(NetworkTemplate template, int fields) {
+                enforceTemplatePermissions(template, callingPackage);
+                return internalGetHistoryForNetwork(template, restrictedFlags, fields,
+                        mAccessLevel, mCallingUid, Long.MIN_VALUE, Long.MAX_VALUE);
+            }
+
+            @Override
+            public NetworkStatsHistory getHistoryIntervalForNetwork(NetworkTemplate template,
+                    int fields, long start, long end) {
+                enforceTemplatePermissions(template, callingPackage);
+                // TODO(b/200768422): Redact returned history if the template is location
+                //  sensitive but the caller is not privileged.
+                return internalGetHistoryForNetwork(template, restrictedFlags, fields,
+                        mAccessLevel, mCallingUid, start, end);
+            }
+
+            @Override
+            public NetworkStats getSummaryForAllUid(
+                    NetworkTemplate template, long start, long end, boolean includeTags) {
+                enforceTemplatePermissions(template, callingPackage);
+                try {
+                    final NetworkStats stats = getUidComplete()
+                            .getSummary(template, start, end, mAccessLevel, mCallingUid);
+                    if (includeTags) {
+                        final NetworkStats tagStats = getUidTagComplete()
+                                .getSummary(template, start, end, mAccessLevel, mCallingUid);
+                        stats.combineAllValues(tagStats);
+                    }
+                    return stats;
+                } catch (NullPointerException e) {
+                    throw e;
+                }
+            }
+
+            @Override
+            public NetworkStats getTaggedSummaryForAllUid(
+                    NetworkTemplate template, long start, long end) {
+                enforceTemplatePermissions(template, callingPackage);
+                try {
+                    final NetworkStats tagStats = getUidTagComplete()
+                            .getSummary(template, start, end, mAccessLevel, mCallingUid);
+                    return tagStats;
+                } catch (NullPointerException e) {
+                    throw e;
+                }
+            }
+
+            @Override
+            public NetworkStatsHistory getHistoryForUid(
+                    NetworkTemplate template, int uid, int set, int tag, int fields) {
+                enforceTemplatePermissions(template, callingPackage);
+                // NOTE: We don't augment UID-level statistics
+                if (tag == TAG_NONE) {
+                    return getUidComplete().getHistory(template, null, uid, set, tag, fields,
+                            Long.MIN_VALUE, Long.MAX_VALUE, mAccessLevel, mCallingUid);
+                } else {
+                    return getUidTagComplete().getHistory(template, null, uid, set, tag, fields,
+                            Long.MIN_VALUE, Long.MAX_VALUE, mAccessLevel, mCallingUid);
+                }
+            }
+
+            @Override
+            public NetworkStatsHistory getHistoryIntervalForUid(
+                    NetworkTemplate template, int uid, int set, int tag, int fields,
+                    long start, long end) {
+                enforceTemplatePermissions(template, callingPackage);
+                // TODO(b/200768422): Redact returned history if the template is location
+                //  sensitive but the caller is not privileged.
+                // NOTE: We don't augment UID-level statistics
+                if (tag == TAG_NONE) {
+                    return getUidComplete().getHistory(template, null, uid, set, tag, fields,
+                            start, end, mAccessLevel, mCallingUid);
+                } else if (uid == Binder.getCallingUid()) {
+                    return getUidTagComplete().getHistory(template, null, uid, set, tag, fields,
+                            start, end, mAccessLevel, mCallingUid);
+                } else {
+                    throw new SecurityException("Calling package " + mCallingPackage
+                            + " cannot access tag information from a different uid");
+                }
+            }
+
+            @Override
+            public void close() {
+                mUidComplete = null;
+                mUidTagComplete = null;
+            }
+        };
+    }
+
+    private void enforceTemplatePermissions(@NonNull NetworkTemplate template,
+            @NonNull String callingPackage) {
+        // For a template with wifi network keys, it is possible for a malicious
+        // client to track the user locations via querying data usage. Thus, enforce
+        // fine location permission check.
+        if (!template.getWifiNetworkKeys().isEmpty()) {
+            final boolean canAccessFineLocation = mLocationPermissionChecker
+                    .checkCallersLocationPermission(callingPackage,
+                    null /* featureId */,
+                            Binder.getCallingUid(),
+                            false /* coarseForTargetSdkLessThanQ */,
+                            null /* message */);
+            if (!canAccessFineLocation) {
+                throw new SecurityException("Access fine location is required when querying"
+                        + " with wifi network keys, make sure the app has the necessary"
+                        + "permissions and the location toggle is on.");
+            }
+        }
+    }
+
+    private @NetworkStatsAccess.Level int checkAccessLevel(String callingPackage) {
+        return NetworkStatsAccess.checkAccessLevel(
+                mContext, Binder.getCallingPid(), Binder.getCallingUid(), callingPackage);
+    }
+
+    /**
+     * Find the most relevant {@link SubscriptionPlan} for the given
+     * {@link NetworkTemplate} and flags. This is typically used to augment
+     * local measurement results to match a known anchor from the carrier.
+     */
+    private SubscriptionPlan resolveSubscriptionPlan(NetworkTemplate template, int flags) {
+        SubscriptionPlan plan = null;
+        if ((flags & NetworkStatsManager.FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN) != 0
+                && mSettings.getAugmentEnabled()) {
+            if (LOGD) Log.d(TAG, "Resolving plan for " + template);
+            final long token = Binder.clearCallingIdentity();
+            try {
+                plan = mContext.getSystemService(NetworkPolicyManager.class)
+                        .getSubscriptionPlan(template);
+            } finally {
+                Binder.restoreCallingIdentity(token);
+            }
+            if (LOGD) Log.d(TAG, "Resolved to plan " + plan);
+        }
+        return plan;
+    }
+
+    /**
+     * Return network summary, splicing between DEV and XT stats when
+     * appropriate.
+     */
+    private NetworkStats internalGetSummaryForNetwork(NetworkTemplate template, int flags,
+            long start, long end, @NetworkStatsAccess.Level int accessLevel, int callingUid) {
+        // We've been using pure XT stats long enough that we no longer need to
+        // splice DEV and XT together.
+        final NetworkStatsHistory history = internalGetHistoryForNetwork(template, flags, FIELD_ALL,
+                accessLevel, callingUid, start, end);
+
+        final long now = System.currentTimeMillis();
+        final NetworkStatsHistory.Entry entry = history.getValues(start, end, now, null);
+
+        final NetworkStats stats = new NetworkStats(end - start, 1);
+        stats.insertEntry(new NetworkStats.Entry(IFACE_ALL, UID_ALL, SET_ALL, TAG_NONE,
+                METERED_ALL, ROAMING_ALL, DEFAULT_NETWORK_ALL, entry.rxBytes, entry.rxPackets,
+                entry.txBytes, entry.txPackets, entry.operations));
+        return stats;
+    }
+
+    /**
+     * Return network history, splicing between DEV and XT stats when
+     * appropriate.
+     */
+    private NetworkStatsHistory internalGetHistoryForNetwork(NetworkTemplate template,
+            int flags, int fields, @NetworkStatsAccess.Level int accessLevel, int callingUid,
+            long start, long end) {
+        // We've been using pure XT stats long enough that we no longer need to
+        // splice DEV and XT together.
+        final SubscriptionPlan augmentPlan = resolveSubscriptionPlan(template, flags);
+        synchronized (mStatsLock) {
+            return mXtStatsCached.getHistory(template, augmentPlan,
+                    UID_ALL, SET_ALL, TAG_NONE, fields, start, end, accessLevel, callingUid);
+        }
+    }
+
+    private long getNetworkTotalBytes(NetworkTemplate template, long start, long end) {
+        assertSystemReady();
+
+        return internalGetSummaryForNetwork(template,
+                NetworkStatsManager.FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN, start, end,
+                NetworkStatsAccess.Level.DEVICE, Binder.getCallingUid()).getTotalBytes();
+    }
+
+    private NetworkStats getNetworkUidBytes(NetworkTemplate template, long start, long end) {
+        assertSystemReady();
+
+        final NetworkStatsCollection uidComplete;
+        synchronized (mStatsLock) {
+            uidComplete = mUidRecorder.getOrLoadCompleteLocked();
+        }
+        return uidComplete.getSummary(template, start, end, NetworkStatsAccess.Level.DEVICE,
+                android.os.Process.SYSTEM_UID);
+    }
+
+    @Override
+    public NetworkStats getDataLayerSnapshotForUid(int uid) throws RemoteException {
+        if (Binder.getCallingUid() != uid) {
+            Log.w(TAG, "Snapshots only available for calling UID");
+            return new NetworkStats(SystemClock.elapsedRealtime(), 0);
+        }
+
+        // TODO: switch to data layer stats once kernel exports
+        // for now, read network layer stats and flatten across all ifaces.
+        // This function is used to query NeworkStats for calle's uid. The only caller method
+        // TrafficStats#getDataLayerSnapshotForUid alrady claim no special permission to query
+        // its own NetworkStats.
+        final long ident = Binder.clearCallingIdentity();
+        final NetworkStats networkLayer;
+        try {
+            networkLayer = readNetworkStatsUidDetail(uid, INTERFACES_ALL, TAG_ALL);
+        } finally {
+            Binder.restoreCallingIdentity(ident);
+        }
+
+        // splice in operation counts
+        networkLayer.spliceOperationsFrom(mUidOperations);
+
+        final NetworkStats dataLayer = new NetworkStats(
+                networkLayer.getElapsedRealtime(), networkLayer.size());
+
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < networkLayer.size(); i++) {
+            entry = networkLayer.getValues(i, entry);
+            entry.iface = IFACE_ALL;
+            dataLayer.combineValues(entry);
+        }
+
+        return dataLayer;
+    }
+
+    @Override
+    public NetworkStats getUidStatsForTransport(int transport) {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+        try {
+            final String[] relevantIfaces =
+                    transport == TRANSPORT_WIFI ? mWifiIfaces : mMobileIfaces;
+            // TODO(b/215633405) : mMobileIfaces and mWifiIfaces already contain the stacked
+            // interfaces, so this is not useful, remove it.
+            final String[] ifacesToQuery =
+                    mStatsFactory.augmentWithStackedInterfaces(relevantIfaces);
+            return getNetworkStatsUidDetail(ifacesToQuery);
+        } catch (RemoteException e) {
+            Log.wtf(TAG, "Error compiling UID stats", e);
+            return new NetworkStats(0L, 0);
+        }
+    }
+
+    @Override
+    public String[] getMobileIfaces() {
+        // TODO (b/192758557): Remove debug log.
+        if (CollectionUtils.contains(mMobileIfaces, null)) {
+            throw new NullPointerException(
+                    "null element in mMobileIfaces: " + Arrays.toString(mMobileIfaces));
+        }
+        return mMobileIfaces.clone();
+    }
+
+    @Override
+    public void incrementOperationCount(int uid, int tag, int operationCount) {
+        if (Binder.getCallingUid() != uid) {
+            mContext.enforceCallingOrSelfPermission(UPDATE_DEVICE_STATS, TAG);
+        }
+
+        if (operationCount < 0) {
+            throw new IllegalArgumentException("operation count can only be incremented");
+        }
+        if (tag == TAG_NONE) {
+            throw new IllegalArgumentException("operation count must have specific tag");
+        }
+
+        synchronized (mStatsLock) {
+            final int set = mActiveUidCounterSet.get(uid, SET_DEFAULT);
+            mUidOperations.combineValues(
+                    mActiveIface, uid, set, tag, 0L, 0L, 0L, 0L, operationCount);
+            mUidOperations.combineValues(
+                    mActiveIface, uid, set, TAG_NONE, 0L, 0L, 0L, 0L, operationCount);
+        }
+    }
+
+    private void setKernelCounterSet(int uid, int set) {
+        if (mUidCounterSetMap == null) {
+            Log.wtf(TAG, "Fail to set UidCounterSet: Null bpf map");
+            return;
+        }
+
+        if (set == SET_DEFAULT) {
+            try {
+                mUidCounterSetMap.deleteEntry(new U32(uid));
+            } catch (ErrnoException e) {
+                Log.w(TAG, "UidCounterSetMap.deleteEntry(" + uid + ") failed with errno: " + e);
+            }
+            return;
+        }
+
+        try {
+            mUidCounterSetMap.updateEntry(new U32(uid), new U8((short) set));
+        } catch (ErrnoException e) {
+            Log.w(TAG, "UidCounterSetMap.updateEntry(" + uid + ", " + set
+                    + ") failed with errno: " + e);
+        }
+    }
+
+    @VisibleForTesting
+    public void noteUidForeground(int uid, boolean uidForeground) {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+        synchronized (mStatsLock) {
+            final int set = uidForeground ? SET_FOREGROUND : SET_DEFAULT;
+            final int oldSet = mActiveUidCounterSet.get(uid, SET_DEFAULT);
+            if (oldSet != set) {
+                mActiveUidCounterSet.put(uid, set);
+                setKernelCounterSet(uid, set);
+            }
+        }
+    }
+
+    /**
+     * Notify {@code NetworkStatsService} about network status changed.
+     */
+    public void notifyNetworkStatus(
+            @NonNull Network[] defaultNetworks,
+            @NonNull NetworkStateSnapshot[] networkStates,
+            @Nullable String activeIface,
+            @NonNull UnderlyingNetworkInfo[] underlyingNetworkInfos) {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+
+        final long token = Binder.clearCallingIdentity();
+        try {
+            handleNotifyNetworkStatus(defaultNetworks, networkStates, activeIface);
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+
+        // Update the VPN underlying interfaces only after the poll is made and tun data has been
+        // migrated. Otherwise the migration would use the new interfaces instead of the ones that
+        // were current when the polled data was transferred.
+        mStatsFactory.updateUnderlyingNetworkInfos(underlyingNetworkInfos);
+    }
+
+    @Override
+    public void forceUpdate() {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+
+        final long token = Binder.clearCallingIdentity();
+        try {
+            performPoll(FLAG_PERSIST_ALL);
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+    }
+
+    /** Advise persistence threshold; may be overridden internally. */
+    public void advisePersistThreshold(long thresholdBytes) {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+        // clamp threshold into safe range
+        mPersistThreshold = NetworkStatsUtils.constrain(thresholdBytes,
+                128 * KB_IN_BYTES, 2 * MB_IN_BYTES);
+        if (LOGV) {
+            Log.v(TAG, "advisePersistThreshold() given " + thresholdBytes + ", clamped to "
+                    + mPersistThreshold);
+        }
+
+        final long oldGlobalAlertBytes = mGlobalAlertBytes;
+
+        // update and persist if beyond new thresholds
+        final long currentTime = mClock.millis();
+        synchronized (mStatsLock) {
+            if (!mSystemReady) return;
+
+            updatePersistThresholdsLocked();
+
+            mDevRecorder.maybePersistLocked(currentTime);
+            mXtRecorder.maybePersistLocked(currentTime);
+            mUidRecorder.maybePersistLocked(currentTime);
+            mUidTagRecorder.maybePersistLocked(currentTime);
+        }
+
+        if (oldGlobalAlertBytes != mGlobalAlertBytes) {
+            registerGlobalAlert();
+        }
+    }
+
+    @Override
+    public DataUsageRequest registerUsageCallback(@NonNull String callingPackage,
+                @NonNull DataUsageRequest request, @NonNull IUsageCallback callback) {
+        Objects.requireNonNull(callingPackage, "calling package is null");
+        Objects.requireNonNull(request, "DataUsageRequest is null");
+        Objects.requireNonNull(request.template, "NetworkTemplate is null");
+        Objects.requireNonNull(callback, "callback is null");
+
+        int callingUid = Binder.getCallingUid();
+        @NetworkStatsAccess.Level int accessLevel = checkAccessLevel(callingPackage);
+        DataUsageRequest normalizedRequest;
+        final long token = Binder.clearCallingIdentity();
+        try {
+            normalizedRequest = mStatsObservers.register(mContext,
+                    request, callback, callingUid, accessLevel);
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+
+        // Create baseline stats
+        mHandler.sendMessage(mHandler.obtainMessage(MSG_PERFORM_POLL));
+
+        return normalizedRequest;
+   }
+
+    @Override
+    public void unregisterUsageRequest(DataUsageRequest request) {
+        Objects.requireNonNull(request, "DataUsageRequest is null");
+
+        int callingUid = Binder.getCallingUid();
+        final long token = Binder.clearCallingIdentity();
+        try {
+            mStatsObservers.unregister(request, callingUid);
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+    }
+
+    @Override
+    public long getUidStats(int uid, int type) {
+        final int callingUid = Binder.getCallingUid();
+        if (callingUid != android.os.Process.SYSTEM_UID && callingUid != uid) {
+            return UNSUPPORTED;
+        }
+        return nativeGetUidStat(uid, type);
+    }
+
+    @Override
+    public long getIfaceStats(@NonNull String iface, int type) {
+        Objects.requireNonNull(iface);
+        long nativeIfaceStats = nativeGetIfaceStat(iface, type);
+        if (nativeIfaceStats == -1) {
+            return nativeIfaceStats;
+        } else {
+            // When tethering offload is in use, nativeIfaceStats does not contain usage from
+            // offload, add it back here. Note that the included statistics might be stale
+            // since polling newest stats from hardware might impact system health and not
+            // suitable for TrafficStats API use cases.
+            return nativeIfaceStats + getProviderIfaceStats(iface, type);
+        }
+    }
+
+    @Override
+    public long getTotalStats(int type) {
+        long nativeTotalStats = nativeGetTotalStat(type);
+        if (nativeTotalStats == -1) {
+            return nativeTotalStats;
+        } else {
+            // Refer to comment in getIfaceStats
+            return nativeTotalStats + getProviderIfaceStats(IFACE_ALL, type);
+        }
+    }
+
+    private long getProviderIfaceStats(@Nullable String iface, int type) {
+        final NetworkStats providerSnapshot = getNetworkStatsFromProviders(STATS_PER_IFACE);
+        final HashSet<String> limitIfaces;
+        if (iface == IFACE_ALL) {
+            limitIfaces = null;
+        } else {
+            limitIfaces = new HashSet<>();
+            limitIfaces.add(iface);
+        }
+        final NetworkStats.Entry entry = providerSnapshot.getTotal(null, limitIfaces);
+        switch (type) {
+            case TrafficStats.TYPE_RX_BYTES:
+                return entry.rxBytes;
+            case TrafficStats.TYPE_RX_PACKETS:
+                return entry.rxPackets;
+            case TrafficStats.TYPE_TX_BYTES:
+                return entry.txBytes;
+            case TrafficStats.TYPE_TX_PACKETS:
+                return entry.txPackets;
+            default:
+                return 0;
+        }
+    }
+
+    /**
+     * Update {@link NetworkStatsRecorder} and {@link #mGlobalAlertBytes} to
+     * reflect current {@link #mPersistThreshold} value. Always defers to
+     * {@link Global} values when defined.
+     */
+    @GuardedBy("mStatsLock")
+    private void updatePersistThresholdsLocked() {
+        mDevRecorder.setPersistThreshold(mSettings.getDevPersistBytes(mPersistThreshold));
+        mXtRecorder.setPersistThreshold(mSettings.getXtPersistBytes(mPersistThreshold));
+        mUidRecorder.setPersistThreshold(mSettings.getUidPersistBytes(mPersistThreshold));
+        mUidTagRecorder.setPersistThreshold(mSettings.getUidTagPersistBytes(mPersistThreshold));
+        mGlobalAlertBytes = mSettings.getGlobalAlertBytes(mPersistThreshold);
+    }
+
+    /**
+     * Listener that watches for {@link TetheringManager} to claim interface pairs.
+     */
+    private final TetheringManager.TetheringEventCallback mTetherListener =
+            new TetheringManager.TetheringEventCallback() {
+                @Override
+                public void onUpstreamChanged(@Nullable Network network) {
+                    performPoll(FLAG_PERSIST_NETWORK);
+                }
+            };
+
+    private BroadcastReceiver mPollReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            // on background handler thread, and verified UPDATE_DEVICE_STATS
+            // permission above.
+            performPoll(FLAG_PERSIST_ALL);
+
+            // verify that we're watching global alert
+            registerGlobalAlert();
+        }
+    };
+
+    private BroadcastReceiver mRemovedReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            // on background handler thread, and UID_REMOVED is protected
+            // broadcast.
+
+            final int uid = intent.getIntExtra(EXTRA_UID, -1);
+            if (uid == -1) return;
+
+            synchronized (mStatsLock) {
+                mWakeLock.acquire();
+                try {
+                    removeUidsLocked(uid);
+                } finally {
+                    mWakeLock.release();
+                }
+            }
+        }
+    };
+
+    private BroadcastReceiver mUserReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            // On background handler thread, and USER_REMOVED is protected
+            // broadcast.
+
+            final UserHandle userHandle = intent.getParcelableExtra(Intent.EXTRA_USER);
+            if (userHandle == null) return;
+
+            synchronized (mStatsLock) {
+                mWakeLock.acquire();
+                try {
+                    removeUserLocked(userHandle);
+                } finally {
+                    mWakeLock.release();
+                }
+            }
+        }
+    };
+
+    private BroadcastReceiver mShutdownReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            // SHUTDOWN is protected broadcast.
+            synchronized (mStatsLock) {
+                shutdownLocked();
+            }
+        }
+    };
+
+    /**
+     * Handle collapsed RAT type changed event.
+     */
+    @VisibleForTesting
+    public void handleOnCollapsedRatTypeChanged() {
+        // Protect service from frequently updating. Remove pending messages if any.
+        mHandler.removeMessages(MSG_NOTIFY_NETWORK_STATUS);
+        mHandler.sendMessageDelayed(
+                mHandler.obtainMessage(MSG_NOTIFY_NETWORK_STATUS), mSettings.getPollDelay());
+    }
+
+    private void handleNotifyNetworkStatus(
+            Network[] defaultNetworks,
+            NetworkStateSnapshot[] snapshots,
+            String activeIface) {
+        synchronized (mStatsLock) {
+            mWakeLock.acquire();
+            try {
+                mActiveIface = activeIface;
+                handleNotifyNetworkStatusLocked(defaultNetworks, snapshots);
+            } finally {
+                mWakeLock.release();
+            }
+        }
+    }
+
+    /**
+     * Inspect all current {@link NetworkStateSnapshot}s to derive mapping from {@code iface} to
+     * {@link NetworkStatsHistory}. When multiple networks are active on a single {@code iface},
+     * they are combined under a single {@link NetworkIdentitySet}.
+     */
+    @GuardedBy("mStatsLock")
+    private void handleNotifyNetworkStatusLocked(@NonNull Network[] defaultNetworks,
+            @NonNull NetworkStateSnapshot[] snapshots) {
+        if (!mSystemReady) return;
+        if (LOGV) Log.v(TAG, "handleNotifyNetworkStatusLocked()");
+
+        // take one last stats snapshot before updating iface mapping. this
+        // isn't perfect, since the kernel may already be counting traffic from
+        // the updated network.
+
+        // poll, but only persist network stats to keep codepath fast. UID stats
+        // will be persisted during next alarm poll event.
+        performPollLocked(FLAG_PERSIST_NETWORK);
+
+        // Rebuild active interfaces based on connected networks
+        mActiveIfaces.clear();
+        mActiveUidIfaces.clear();
+        // Update the list of default networks.
+        mDefaultNetworks = defaultNetworks;
+
+        mLastNetworkStateSnapshots = snapshots;
+
+        final boolean combineSubtypeEnabled = mSettings.getCombineSubtypeEnabled();
+        final ArraySet<String> mobileIfaces = new ArraySet<>();
+        final ArraySet<String> wifiIfaces = new ArraySet<>();
+        for (NetworkStateSnapshot snapshot : snapshots) {
+            final int displayTransport =
+                    getDisplayTransport(snapshot.getNetworkCapabilities().getTransportTypes());
+            final boolean isMobile = (NetworkCapabilities.TRANSPORT_CELLULAR == displayTransport);
+            final boolean isWifi = (NetworkCapabilities.TRANSPORT_WIFI == displayTransport);
+            final boolean isDefault = CollectionUtils.contains(
+                    mDefaultNetworks, snapshot.getNetwork());
+            final int ratType = combineSubtypeEnabled ? NetworkTemplate.NETWORK_TYPE_ALL
+                    : getRatTypeForStateSnapshot(snapshot);
+            final NetworkIdentity ident = NetworkIdentity.buildNetworkIdentity(mContext, snapshot,
+                    isDefault, ratType);
+
+            // Traffic occurring on the base interface is always counted for
+            // both total usage and UID details.
+            final String baseIface = snapshot.getLinkProperties().getInterfaceName();
+            if (baseIface != null) {
+                findOrCreateNetworkIdentitySet(mActiveIfaces, baseIface).add(ident);
+                findOrCreateNetworkIdentitySet(mActiveUidIfaces, baseIface).add(ident);
+
+                // Build a separate virtual interface for VT (Video Telephony) data usage.
+                // Only do this when IMS is not metered, but VT is metered.
+                // If IMS is metered, then the IMS network usage has already included VT usage.
+                // VT is considered always metered in framework's layer. If VT is not metered
+                // per carrier's policy, modem will report 0 usage for VT calls.
+                if (snapshot.getNetworkCapabilities().hasCapability(
+                        NetworkCapabilities.NET_CAPABILITY_IMS) && !ident.isMetered()) {
+
+                    // Copy the identify from IMS one but mark it as metered.
+                    NetworkIdentity vtIdent = new NetworkIdentity.Builder()
+                            .setType(ident.getType())
+                            .setRatType(ident.getRatType())
+                            .setSubscriberId(ident.getSubscriberId())
+                            .setWifiNetworkKey(ident.getWifiNetworkKey())
+                            .setRoaming(ident.isRoaming()).setMetered(true)
+                            .setDefaultNetwork(true)
+                            .setOemManaged(ident.getOemManaged())
+                            .setSubId(ident.getSubId()).build();
+                    final String ifaceVt = IFACE_VT + getSubIdForMobile(snapshot);
+                    findOrCreateNetworkIdentitySet(mActiveIfaces, ifaceVt).add(vtIdent);
+                    findOrCreateNetworkIdentitySet(mActiveUidIfaces, ifaceVt).add(vtIdent);
+                }
+
+                if (isMobile) {
+                    mobileIfaces.add(baseIface);
+                }
+                if (isWifi) {
+                    wifiIfaces.add(baseIface);
+                }
+            }
+
+            // Traffic occurring on stacked interfaces is usually clatd.
+            //
+            // UID stats are always counted on the stacked interface and never on the base
+            // interface, because the packets on the base interface do not actually match
+            // application sockets (they're not IPv4) and thus the app uid is not known.
+            // For receive this is obvious: packets must be translated from IPv6 to IPv4
+            // before the application socket can be found.
+            // For transmit: either they go through the clat daemon which by virtue of going
+            // through userspace strips the original socket association during the IPv4 to
+            // IPv6 translation process, or they are offloaded by eBPF, which doesn't:
+            // However, on an ebpf device the accounting is done in cgroup ebpf hooks,
+            // which don't trigger again post ebpf translation.
+            // (as such stats accounted to the clat uid are ignored)
+            //
+            // Interface stats are more complicated.
+            //
+            // eBPF offloaded 464xlat'ed packets never hit base interface ip6tables, and thus
+            // *all* statistics are collected by iptables on the stacked v4-* interface.
+            //
+            // Additionally for ingress all packets bound for the clat IPv6 address are dropped
+            // in ip6tables raw prerouting and thus even non-offloaded packets are only
+            // accounted for on the stacked interface.
+            //
+            // For egress, packets subject to eBPF offload never appear on the base interface
+            // and only appear on the stacked interface. Thus to ensure packets increment
+            // interface stats, we must collate data from stacked interfaces. For xt_qtaguid
+            // (or non eBPF offloaded) TX they would appear on both, however egress interface
+            // accounting is explicitly bypassed for traffic from the clat uid.
+            //
+            // TODO: This code might be combined to above code.
+            for (String iface : snapshot.getLinkProperties().getAllInterfaceNames()) {
+                // baseIface has been handled, so ignore it.
+                if (TextUtils.equals(baseIface, iface)) continue;
+                if (iface != null) {
+                    findOrCreateNetworkIdentitySet(mActiveIfaces, iface).add(ident);
+                    findOrCreateNetworkIdentitySet(mActiveUidIfaces, iface).add(ident);
+                    if (isMobile) {
+                        mobileIfaces.add(iface);
+                    }
+                    if (isWifi) {
+                        wifiIfaces.add(iface);
+                    }
+
+                    mStatsFactory.noteStackedIface(iface, baseIface);
+                }
+            }
+        }
+
+        mMobileIfaces = mobileIfaces.toArray(new String[0]);
+        mWifiIfaces = wifiIfaces.toArray(new String[0]);
+        // TODO (b/192758557): Remove debug log.
+        if (CollectionUtils.contains(mMobileIfaces, null)) {
+            throw new NullPointerException(
+                    "null element in mMobileIfaces: " + Arrays.toString(mMobileIfaces));
+        }
+        if (CollectionUtils.contains(mWifiIfaces, null)) {
+            throw new NullPointerException(
+                    "null element in mWifiIfaces: " + Arrays.toString(mWifiIfaces));
+        }
+    }
+
+    private static int getSubIdForMobile(@NonNull NetworkStateSnapshot state) {
+        if (!state.getNetworkCapabilities().hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
+            throw new IllegalArgumentException("Mobile state need capability TRANSPORT_CELLULAR");
+        }
+
+        final NetworkSpecifier spec = state.getNetworkCapabilities().getNetworkSpecifier();
+        if (spec instanceof TelephonyNetworkSpecifier) {
+             return ((TelephonyNetworkSpecifier) spec).getSubscriptionId();
+        } else {
+            Log.wtf(TAG, "getSubIdForState invalid NetworkSpecifier");
+            return INVALID_SUBSCRIPTION_ID;
+        }
+    }
+
+    /**
+     * For networks with {@code TRANSPORT_CELLULAR}, get ratType that was obtained through
+     * {@link PhoneStateListener}. Otherwise, return 0 given that other networks with different
+     * transport types do not actually fill this value.
+     */
+    private int getRatTypeForStateSnapshot(@NonNull NetworkStateSnapshot state) {
+        if (!state.getNetworkCapabilities().hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
+            return 0;
+        }
+
+        return mNetworkStatsSubscriptionsMonitor.getRatTypeForSubscriberId(state.getSubscriberId());
+    }
+
+    private static <K> NetworkIdentitySet findOrCreateNetworkIdentitySet(
+            ArrayMap<K, NetworkIdentitySet> map, K key) {
+        NetworkIdentitySet ident = map.get(key);
+        if (ident == null) {
+            ident = new NetworkIdentitySet();
+            map.put(key, ident);
+        }
+        return ident;
+    }
+
+    @GuardedBy("mStatsLock")
+    private void recordSnapshotLocked(long currentTime) throws RemoteException {
+        // snapshot and record current counters; read UID stats first to
+        // avoid over counting dev stats.
+        Trace.traceBegin(TRACE_TAG_NETWORK, "snapshotUid");
+        final NetworkStats uidSnapshot = getNetworkStatsUidDetail(INTERFACES_ALL);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+        Trace.traceBegin(TRACE_TAG_NETWORK, "snapshotXt");
+        final NetworkStats xtSnapshot = readNetworkStatsSummaryXt();
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+        Trace.traceBegin(TRACE_TAG_NETWORK, "snapshotDev");
+        final NetworkStats devSnapshot = readNetworkStatsSummaryDev();
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+
+        // Snapshot for dev/xt stats from all custom stats providers. Counts per-interface data
+        // from stats providers that isn't already counted by dev and XT stats.
+        Trace.traceBegin(TRACE_TAG_NETWORK, "snapshotStatsProvider");
+        final NetworkStats providersnapshot = getNetworkStatsFromProviders(STATS_PER_IFACE);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+        xtSnapshot.combineAllValues(providersnapshot);
+        devSnapshot.combineAllValues(providersnapshot);
+
+        // For xt/dev, we pass a null VPN array because usage is aggregated by UID, so VPN traffic
+        // can't be reattributed to responsible apps.
+        Trace.traceBegin(TRACE_TAG_NETWORK, "recordDev");
+        mDevRecorder.recordSnapshotLocked(devSnapshot, mActiveIfaces, currentTime);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+        Trace.traceBegin(TRACE_TAG_NETWORK, "recordXt");
+        mXtRecorder.recordSnapshotLocked(xtSnapshot, mActiveIfaces, currentTime);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+
+        // For per-UID stats, pass the VPN info so VPN traffic is reattributed to responsible apps.
+        Trace.traceBegin(TRACE_TAG_NETWORK, "recordUid");
+        mUidRecorder.recordSnapshotLocked(uidSnapshot, mActiveUidIfaces, currentTime);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+        Trace.traceBegin(TRACE_TAG_NETWORK, "recordUidTag");
+        mUidTagRecorder.recordSnapshotLocked(uidSnapshot, mActiveUidIfaces, currentTime);
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+
+        // We need to make copies of member fields that are sent to the observer to avoid
+        // a race condition between the service handler thread and the observer's
+        mStatsObservers.updateStats(xtSnapshot, uidSnapshot, new ArrayMap<>(mActiveIfaces),
+                new ArrayMap<>(mActiveUidIfaces), currentTime);
+    }
+
+    /**
+     * Bootstrap initial stats snapshot, usually during {@link #systemReady()}
+     * so we have baseline values without double-counting.
+     */
+    @GuardedBy("mStatsLock")
+    private void bootstrapStatsLocked() {
+        final long currentTime = mClock.millis();
+
+        try {
+            recordSnapshotLocked(currentTime);
+        } catch (IllegalStateException e) {
+            Log.w(TAG, "problem reading network stats: " + e);
+        } catch (RemoteException e) {
+            // ignored; service lives in system_server
+        }
+    }
+
+    private void performPoll(int flags) {
+        synchronized (mStatsLock) {
+            mWakeLock.acquire();
+
+            try {
+                performPollLocked(flags);
+            } finally {
+                mWakeLock.release();
+            }
+        }
+    }
+
+    /**
+     * Periodic poll operation, reading current statistics and recording into
+     * {@link NetworkStatsHistory}.
+     */
+    @GuardedBy("mStatsLock")
+    private void performPollLocked(int flags) {
+        if (!mSystemReady) return;
+        if (LOGV) Log.v(TAG, "performPollLocked(flags=0x" + Integer.toHexString(flags) + ")");
+        Trace.traceBegin(TRACE_TAG_NETWORK, "performPollLocked");
+
+        final boolean persistNetwork = (flags & FLAG_PERSIST_NETWORK) != 0;
+        final boolean persistUid = (flags & FLAG_PERSIST_UID) != 0;
+        final boolean persistForce = (flags & FLAG_PERSIST_FORCE) != 0;
+
+        performPollFromProvidersLocked();
+
+        // TODO: consider marking "untrusted" times in historical stats
+        final long currentTime = mClock.millis();
+
+        try {
+            recordSnapshotLocked(currentTime);
+        } catch (IllegalStateException e) {
+            Log.wtf(TAG, "problem reading network stats", e);
+            return;
+        } catch (RemoteException e) {
+            // ignored; service lives in system_server
+            return;
+        }
+
+        // persist any pending data depending on requested flags
+        Trace.traceBegin(TRACE_TAG_NETWORK, "[persisting]");
+        if (persistForce) {
+            mDevRecorder.forcePersistLocked(currentTime);
+            mXtRecorder.forcePersistLocked(currentTime);
+            mUidRecorder.forcePersistLocked(currentTime);
+            mUidTagRecorder.forcePersistLocked(currentTime);
+        } else {
+            if (persistNetwork) {
+                mDevRecorder.maybePersistLocked(currentTime);
+                mXtRecorder.maybePersistLocked(currentTime);
+            }
+            if (persistUid) {
+                mUidRecorder.maybePersistLocked(currentTime);
+                mUidTagRecorder.maybePersistLocked(currentTime);
+            }
+        }
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+
+        if (mSettings.getSampleEnabled()) {
+            // sample stats after each full poll
+            performSampleLocked();
+        }
+
+        // finally, dispatch updated event to any listeners
+        mHandler.sendMessage(mHandler.obtainMessage(MSG_BROADCAST_NETWORK_STATS_UPDATED));
+
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+    }
+
+    @GuardedBy("mStatsLock")
+    private void performPollFromProvidersLocked() {
+        // Request asynchronous stats update from all providers for next poll. And wait a bit of
+        // time to allow providers report-in given that normally binder call should be fast. Note
+        // that size of list might be changed because addition/removing at the same time. For
+        // addition, the stats of the missed provider can only be collected in next poll;
+        // for removal, wait might take up to MAX_STATS_PROVIDER_POLL_WAIT_TIME_MS
+        // once that happened.
+        // TODO: request with a valid token.
+        Trace.traceBegin(TRACE_TAG_NETWORK, "provider.requestStatsUpdate");
+        final int registeredCallbackCount = mStatsProviderCbList.size();
+        mStatsProviderSem.drainPermits();
+        invokeForAllStatsProviderCallbacks(
+                (cb) -> cb.mProvider.onRequestStatsUpdate(0 /* unused */));
+        try {
+            mStatsProviderSem.tryAcquire(registeredCallbackCount,
+                    MAX_STATS_PROVIDER_POLL_WAIT_TIME_MS, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException e) {
+            // Strictly speaking it's possible a provider happened to deliver between the timeout
+            // and the log, and that doesn't matter too much as this is just a debug log.
+            Log.d(TAG, "requestStatsUpdate - providers responded "
+                    + mStatsProviderSem.availablePermits()
+                    + "/" + registeredCallbackCount + " : " + e);
+        }
+        Trace.traceEnd(TRACE_TAG_NETWORK);
+    }
+
+    /**
+     * Sample recent statistics summary into {@link EventLog}.
+     */
+    @GuardedBy("mStatsLock")
+    private void performSampleLocked() {
+        // TODO: migrate trustedtime fixes to separate binary log events
+        final long currentTime = mClock.millis();
+
+        NetworkTemplate template;
+        NetworkStats.Entry devTotal;
+        NetworkStats.Entry xtTotal;
+        NetworkStats.Entry uidTotal;
+
+        // collect mobile sample
+        template = buildTemplateMobileWildcard();
+        devTotal = mDevRecorder.getTotalSinceBootLocked(template);
+        xtTotal = mXtRecorder.getTotalSinceBootLocked(template);
+        uidTotal = mUidRecorder.getTotalSinceBootLocked(template);
+
+        EventLog.writeEvent(LOG_TAG_NETSTATS_MOBILE_SAMPLE,
+                devTotal.rxBytes, devTotal.rxPackets, devTotal.txBytes, devTotal.txPackets,
+                xtTotal.rxBytes, xtTotal.rxPackets, xtTotal.txBytes, xtTotal.txPackets,
+                uidTotal.rxBytes, uidTotal.rxPackets, uidTotal.txBytes, uidTotal.txPackets,
+                currentTime);
+
+        // collect wifi sample
+        template = buildTemplateWifiWildcard();
+        devTotal = mDevRecorder.getTotalSinceBootLocked(template);
+        xtTotal = mXtRecorder.getTotalSinceBootLocked(template);
+        uidTotal = mUidRecorder.getTotalSinceBootLocked(template);
+
+        EventLog.writeEvent(LOG_TAG_NETSTATS_WIFI_SAMPLE,
+                devTotal.rxBytes, devTotal.rxPackets, devTotal.txBytes, devTotal.txPackets,
+                xtTotal.rxBytes, xtTotal.rxPackets, xtTotal.txBytes, xtTotal.txPackets,
+                uidTotal.rxBytes, uidTotal.rxPackets, uidTotal.txBytes, uidTotal.txPackets,
+                currentTime);
+    }
+
+    // deleteKernelTagData can ignore ENOENT; otherwise we should log an error
+    private void logErrorIfNotErrNoent(final ErrnoException e, final String msg) {
+        if (e.errno != ENOENT) Log.e(TAG, msg, e);
+    }
+
+    private <K extends StatsMapKey, V extends StatsMapValue> void deleteStatsMapTagData(
+            IBpfMap<K, V> statsMap, int uid) {
+        try {
+            statsMap.forEach((key, value) -> {
+                if (key.uid == uid) {
+                    try {
+                        statsMap.deleteEntry(key);
+                    } catch (ErrnoException e) {
+                        logErrorIfNotErrNoent(e, "Failed to delete data(uid = " + key.uid + ")");
+                    }
+                }
+            });
+        } catch (ErrnoException e) {
+            Log.e(TAG, "FAILED to delete tag data from stats map", e);
+        }
+    }
+
+    /**
+     * Deletes uid tag data from CookieTagMap, StatsMapA, StatsMapB, and UidStatsMap
+     * @param uid
+     */
+    private void deleteKernelTagData(int uid) {
+        try {
+            mCookieTagMap.forEach((key, value) -> {
+                // If SkDestroyListener deletes the socket tag while this code is running,
+                // forEach will either restart iteration from the beginning or return null,
+                // depending on when the deletion happens.
+                // If it returns null, continue iteration to delete the data and in fact it would
+                // just iterate from first key because BpfMap#getNextKey would return first key
+                // if the current key is not exist.
+                if (value != null && value.uid == uid) {
+                    try {
+                        mCookieTagMap.deleteEntry(key);
+                    } catch (ErrnoException e) {
+                        logErrorIfNotErrNoent(e, "Failed to delete data(cookie = " + key + ")");
+                    }
+                }
+            });
+        } catch (ErrnoException e) {
+            Log.e(TAG, "Failed to delete tag data from cookie tag map", e);
+        }
+
+        deleteStatsMapTagData(mStatsMapA, uid);
+        deleteStatsMapTagData(mStatsMapB, uid);
+
+        try {
+            mUidCounterSetMap.deleteEntry(new U32(uid));
+        } catch (ErrnoException e) {
+            logErrorIfNotErrNoent(e, "Failed to delete tag data from uid counter set map");
+        }
+
+        try {
+            mAppUidStatsMap.deleteEntry(new UidStatsMapKey(uid));
+        } catch (ErrnoException e) {
+            logErrorIfNotErrNoent(e, "Failed to delete tag data from app uid stats map");
+        }
+    }
+
+    /**
+     * Clean up {@link #mUidRecorder} after UID is removed.
+     */
+    @GuardedBy("mStatsLock")
+    private void removeUidsLocked(int... uids) {
+        if (LOGV) Log.v(TAG, "removeUidsLocked() for UIDs " + Arrays.toString(uids));
+
+        // Perform one last poll before removing
+        performPollLocked(FLAG_PERSIST_ALL);
+
+        mUidRecorder.removeUidsLocked(uids);
+        mUidTagRecorder.removeUidsLocked(uids);
+
+        // Clear kernel stats associated with UID
+        for (int uid : uids) {
+            deleteKernelTagData(uid);
+        }
+    }
+
+    /**
+     * Clean up {@link #mUidRecorder} after user is removed.
+     */
+    @GuardedBy("mStatsLock")
+    private void removeUserLocked(@NonNull UserHandle userHandle) {
+        if (LOGV) Log.v(TAG, "removeUserLocked() for UserHandle=" + userHandle);
+
+        // Build list of UIDs that we should clean up
+        final ArrayList<Integer> uids = new ArrayList<>();
+        final List<ApplicationInfo> apps = mContext.getPackageManager().getInstalledApplications(
+                PackageManager.MATCH_ANY_USER
+                | PackageManager.MATCH_DISABLED_COMPONENTS);
+        for (ApplicationInfo app : apps) {
+            final int uid = userHandle.getUid(app.uid);
+            uids.add(uid);
+        }
+
+        removeUidsLocked(CollectionUtils.toIntArray(uids));
+    }
+
+    /**
+     * Set the warning and limit to all registered custom network stats providers.
+     * Note that invocation of any interface will be sent to all providers.
+     */
+    public void setStatsProviderWarningAndLimitAsync(
+            @NonNull String iface, long warning, long limit) {
+        PermissionUtils.enforceNetworkStackPermission(mContext);
+        if (LOGV) {
+            Log.v(TAG, "setStatsProviderWarningAndLimitAsync("
+                    + iface + "," + warning + "," + limit + ")");
+        }
+        invokeForAllStatsProviderCallbacks((cb) -> cb.mProvider.onSetWarningAndLimit(iface,
+                warning, limit));
+    }
+
+    @Override
+    protected void dump(FileDescriptor fd, PrintWriter rawWriter, String[] args) {
+        if (!PermissionUtils.checkDumpPermission(mContext, TAG, rawWriter)) return;
+
+        long duration = DateUtils.DAY_IN_MILLIS;
+        final HashSet<String> argSet = new HashSet<String>();
+        for (String arg : args) {
+            argSet.add(arg);
+
+            if (arg.startsWith("--duration=")) {
+                try {
+                    duration = Long.parseLong(arg.substring(11));
+                } catch (NumberFormatException ignored) {
+                }
+            }
+        }
+
+        // usage: dumpsys netstats --full --uid --tag --poll --checkin
+        final boolean poll = argSet.contains("--poll") || argSet.contains("poll");
+        final boolean checkin = argSet.contains("--checkin");
+        final boolean fullHistory = argSet.contains("--full") || argSet.contains("full");
+        final boolean includeUid = argSet.contains("--uid") || argSet.contains("detail");
+        final boolean includeTag = argSet.contains("--tag") || argSet.contains("detail");
+
+        final IndentingPrintWriter pw = new IndentingPrintWriter(rawWriter, "  ");
+
+        synchronized (mStatsLock) {
+            if (args.length > 0 && "--proto".equals(args[0])) {
+                // In this case ignore all other arguments.
+                dumpProtoLocked(fd);
+                return;
+            }
+
+            if (poll) {
+                performPollLocked(FLAG_PERSIST_ALL | FLAG_PERSIST_FORCE);
+                pw.println("Forced poll");
+                return;
+            }
+
+            if (checkin) {
+                final long end = System.currentTimeMillis();
+                final long start = end - duration;
+
+                pw.print("v1,");
+                pw.print(start / SECOND_IN_MILLIS); pw.print(',');
+                pw.print(end / SECOND_IN_MILLIS); pw.println();
+
+                pw.println("xt");
+                mXtRecorder.dumpCheckin(rawWriter, start, end);
+
+                if (includeUid) {
+                    pw.println("uid");
+                    mUidRecorder.dumpCheckin(rawWriter, start, end);
+                }
+                if (includeTag) {
+                    pw.println("tag");
+                    mUidTagRecorder.dumpCheckin(rawWriter, start, end);
+                }
+                return;
+            }
+
+            pw.println("Configs:");
+            pw.increaseIndent();
+            pw.print(NETSTATS_COMBINE_SUBTYPE_ENABLED, mSettings.getCombineSubtypeEnabled());
+            pw.println();
+            pw.decreaseIndent();
+
+            pw.println("Active interfaces:");
+            pw.increaseIndent();
+            for (int i = 0; i < mActiveIfaces.size(); i++) {
+                pw.print("iface", mActiveIfaces.keyAt(i));
+                pw.print("ident", mActiveIfaces.valueAt(i));
+                pw.println();
+            }
+            pw.decreaseIndent();
+
+            pw.println("Active UID interfaces:");
+            pw.increaseIndent();
+            for (int i = 0; i < mActiveUidIfaces.size(); i++) {
+                pw.print("iface", mActiveUidIfaces.keyAt(i));
+                pw.print("ident", mActiveUidIfaces.valueAt(i));
+                pw.println();
+            }
+            pw.decreaseIndent();
+
+            // Get the top openSession callers
+            final SparseIntArray calls;
+            synchronized (mOpenSessionCallsPerUid) {
+                calls = mOpenSessionCallsPerUid.clone();
+            }
+
+            final int N = calls.size();
+            final long[] values = new long[N];
+            for (int j = 0; j < N; j++) {
+                values[j] = ((long) calls.valueAt(j) << 32) | calls.keyAt(j);
+            }
+            Arrays.sort(values);
+
+            pw.println("Top openSession callers (uid=count):");
+            pw.increaseIndent();
+            final int end = Math.max(0, N - DUMP_STATS_SESSION_COUNT);
+            for (int j = N - 1; j >= end; j--) {
+                final int uid = (int) (values[j] & 0xffffffff);
+                final int count = (int) (values[j] >> 32);
+                pw.print(uid); pw.print("="); pw.println(count);
+            }
+            pw.decreaseIndent();
+            pw.println();
+
+            pw.println("Stats Providers:");
+            pw.increaseIndent();
+            invokeForAllStatsProviderCallbacks((cb) -> {
+                pw.println(cb.mTag + " Xt:");
+                pw.increaseIndent();
+                pw.print(cb.getCachedStats(STATS_PER_IFACE).toString());
+                pw.decreaseIndent();
+                if (includeUid) {
+                    pw.println(cb.mTag + " Uid:");
+                    pw.increaseIndent();
+                    pw.print(cb.getCachedStats(STATS_PER_UID).toString());
+                    pw.decreaseIndent();
+                }
+            });
+            pw.decreaseIndent();
+
+            pw.println("Dev stats:");
+            pw.increaseIndent();
+            mDevRecorder.dumpLocked(pw, fullHistory);
+            pw.decreaseIndent();
+
+            pw.println("Xt stats:");
+            pw.increaseIndent();
+            mXtRecorder.dumpLocked(pw, fullHistory);
+            pw.decreaseIndent();
+
+            if (includeUid) {
+                pw.println("UID stats:");
+                pw.increaseIndent();
+                mUidRecorder.dumpLocked(pw, fullHistory);
+                pw.decreaseIndent();
+            }
+
+            if (includeTag) {
+                pw.println("UID tag stats:");
+                pw.increaseIndent();
+                mUidTagRecorder.dumpLocked(pw, fullHistory);
+                pw.decreaseIndent();
+            }
+        }
+    }
+
+    @GuardedBy("mStatsLock")
+    private void dumpProtoLocked(FileDescriptor fd) {
+        final ProtoOutputStream proto = new ProtoOutputStream(new FileOutputStream(fd));
+
+        // TODO Right now it writes all history.  Should it limit to the "since-boot" log?
+
+        dumpInterfaces(proto, NetworkStatsServiceDumpProto.ACTIVE_INTERFACES,
+                mActiveIfaces);
+        dumpInterfaces(proto, NetworkStatsServiceDumpProto.ACTIVE_UID_INTERFACES,
+                mActiveUidIfaces);
+        mDevRecorder.dumpDebugLocked(proto, NetworkStatsServiceDumpProto.DEV_STATS);
+        mXtRecorder.dumpDebugLocked(proto, NetworkStatsServiceDumpProto.XT_STATS);
+        mUidRecorder.dumpDebugLocked(proto, NetworkStatsServiceDumpProto.UID_STATS);
+        mUidTagRecorder.dumpDebugLocked(proto,
+                NetworkStatsServiceDumpProto.UID_TAG_STATS);
+
+        proto.flush();
+    }
+
+    private static void dumpInterfaces(ProtoOutputStream proto, long tag,
+            ArrayMap<String, NetworkIdentitySet> ifaces) {
+        for (int i = 0; i < ifaces.size(); i++) {
+            final long start = proto.start(tag);
+
+            proto.write(NetworkInterfaceProto.INTERFACE, ifaces.keyAt(i));
+            ifaces.valueAt(i).dumpDebug(proto, NetworkInterfaceProto.IDENTITIES);
+
+            proto.end(start);
+        }
+    }
+
+    private NetworkStats readNetworkStatsSummaryDev() {
+        try {
+            return mStatsFactory.readNetworkStatsSummaryDev();
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+
+    private NetworkStats readNetworkStatsSummaryXt() {
+        try {
+            return mStatsFactory.readNetworkStatsSummaryXt();
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+
+    private NetworkStats readNetworkStatsUidDetail(int uid, String[] ifaces, int tag) {
+        try {
+            return mStatsFactory.readNetworkStatsDetail(uid, ifaces, tag);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+
+    /**
+     * Return snapshot of current UID statistics, including any
+     * {@link TrafficStats#UID_TETHERING}, video calling data usage, and {@link #mUidOperations}
+     * values.
+     *
+     * @param ifaces A list of interfaces the stats should be restricted to, or
+     *               {@link NetworkStats#INTERFACES_ALL}.
+     */
+    private NetworkStats getNetworkStatsUidDetail(String[] ifaces)
+            throws RemoteException {
+        final NetworkStats uidSnapshot = readNetworkStatsUidDetail(UID_ALL,  ifaces, TAG_ALL);
+
+        // fold tethering stats and operations into uid snapshot
+        final NetworkStats tetherSnapshot = getNetworkStatsTethering(STATS_PER_UID);
+        tetherSnapshot.filter(UID_ALL, ifaces, TAG_ALL);
+        mStatsFactory.apply464xlatAdjustments(uidSnapshot, tetherSnapshot);
+        uidSnapshot.combineAllValues(tetherSnapshot);
+
+        // get a stale copy of uid stats snapshot provided by providers.
+        final NetworkStats providerStats = getNetworkStatsFromProviders(STATS_PER_UID);
+        providerStats.filter(UID_ALL, ifaces, TAG_ALL);
+        mStatsFactory.apply464xlatAdjustments(uidSnapshot, providerStats);
+        uidSnapshot.combineAllValues(providerStats);
+
+        uidSnapshot.combineAllValues(mUidOperations);
+
+        return uidSnapshot;
+    }
+
+    /**
+     * Return snapshot of current non-offloaded tethering statistics. Will return empty
+     * {@link NetworkStats} if any problems are encountered, or queried by {@code STATS_PER_IFACE}
+     * since it is already included by {@link #nativeGetIfaceStat}.
+     * See {@code OffloadTetheringStatsProvider} for offloaded tethering stats.
+     */
+    // TODO: Remove this by implementing {@link NetworkStatsProvider} for non-offloaded
+    //  tethering stats.
+    private @NonNull NetworkStats getNetworkStatsTethering(int how) throws RemoteException {
+         // We only need to return per-UID stats. Per-device stats are already counted by
+        // interface counters.
+        if (how != STATS_PER_UID) {
+            return new NetworkStats(SystemClock.elapsedRealtime(), 0);
+        }
+
+        final NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 1);
+        try {
+            final TetherStatsParcel[] tetherStatsParcels = mNetd.tetherGetStats();
+            for (TetherStatsParcel tetherStats : tetherStatsParcels) {
+                try {
+                    stats.combineValues(new NetworkStats.Entry(tetherStats.iface, UID_TETHERING,
+                            SET_DEFAULT, TAG_NONE, tetherStats.rxBytes, tetherStats.rxPackets,
+                            tetherStats.txBytes, tetherStats.txPackets, 0L));
+                } catch (ArrayIndexOutOfBoundsException e) {
+                    throw new IllegalStateException("invalid tethering stats " + e);
+                }
+            }
+        } catch (IllegalStateException e) {
+            Log.wtf(TAG, "problem reading network stats", e);
+        }
+        return stats;
+    }
+
+    // TODO: It is copied from ConnectivityService, consider refactor these check permission
+    //  functions to a proper util.
+    private boolean checkAnyPermissionOf(String... permissions) {
+        for (String permission : permissions) {
+            if (mContext.checkCallingOrSelfPermission(permission) == PERMISSION_GRANTED) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private void enforceAnyPermissionOf(String... permissions) {
+        if (!checkAnyPermissionOf(permissions)) {
+            throw new SecurityException("Requires one of the following permissions: "
+                    + String.join(", ", permissions) + ".");
+        }
+    }
+
+    /**
+     * Registers a custom provider of {@link android.net.NetworkStats} to combine the network
+     * statistics that cannot be seen by the kernel to system. To unregister, invoke the
+     * {@code unregister()} of the returned callback.
+     *
+     * @param tag a human readable identifier of the custom network stats provider.
+     * @param provider the {@link INetworkStatsProvider} binder corresponding to the
+     *                 {@link NetworkStatsProvider} to be registered.
+     *
+     * @return a {@link INetworkStatsProviderCallback} binder
+     *         interface, which can be used to report events to the system.
+     */
+    public @NonNull INetworkStatsProviderCallback registerNetworkStatsProvider(
+            @NonNull String tag, @NonNull INetworkStatsProvider provider) {
+        enforceAnyPermissionOf(NETWORK_STATS_PROVIDER,
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK);
+        Objects.requireNonNull(provider, "provider is null");
+        Objects.requireNonNull(tag, "tag is null");
+        final NetworkPolicyManager netPolicyManager = mContext
+                .getSystemService(NetworkPolicyManager.class);
+        try {
+            NetworkStatsProviderCallbackImpl callback = new NetworkStatsProviderCallbackImpl(
+                    tag, provider, mStatsProviderSem, mAlertObserver,
+                    mStatsProviderCbList, netPolicyManager);
+            mStatsProviderCbList.add(callback);
+            Log.d(TAG, "registerNetworkStatsProvider from " + callback.mTag + " uid/pid="
+                    + getCallingUid() + "/" + getCallingPid());
+            return callback;
+        } catch (RemoteException e) {
+            Log.e(TAG, "registerNetworkStatsProvider failed", e);
+        }
+        return null;
+    }
+
+    // Collect stats from local cache of providers.
+    private @NonNull NetworkStats getNetworkStatsFromProviders(int how) {
+        final NetworkStats ret = new NetworkStats(0L, 0);
+        invokeForAllStatsProviderCallbacks((cb) -> ret.combineAllValues(cb.getCachedStats(how)));
+        return ret;
+    }
+
+    @FunctionalInterface
+    private interface ThrowingConsumer<S, T extends Throwable> {
+        void accept(S s) throws T;
+    }
+
+    private void invokeForAllStatsProviderCallbacks(
+            @NonNull ThrowingConsumer<NetworkStatsProviderCallbackImpl, RemoteException> task) {
+        for (final NetworkStatsProviderCallbackImpl cb : mStatsProviderCbList) {
+            try {
+                task.accept(cb);
+            } catch (RemoteException e) {
+                Log.e(TAG, "Fail to broadcast to provider: " + cb.mTag, e);
+            }
+        }
+    }
+
+    private static class NetworkStatsProviderCallbackImpl extends INetworkStatsProviderCallback.Stub
+            implements IBinder.DeathRecipient {
+        @NonNull final String mTag;
+
+        @NonNull final INetworkStatsProvider mProvider;
+        @NonNull private final Semaphore mSemaphore;
+        @NonNull final AlertObserver mAlertObserver;
+        @NonNull final CopyOnWriteArrayList<NetworkStatsProviderCallbackImpl> mStatsProviderCbList;
+        @NonNull final NetworkPolicyManager mNetworkPolicyManager;
+
+        @NonNull private final Object mProviderStatsLock = new Object();
+
+        @GuardedBy("mProviderStatsLock")
+        // Track STATS_PER_IFACE and STATS_PER_UID separately.
+        private final NetworkStats mIfaceStats = new NetworkStats(0L, 0);
+        @GuardedBy("mProviderStatsLock")
+        private final NetworkStats mUidStats = new NetworkStats(0L, 0);
+
+        NetworkStatsProviderCallbackImpl(
+                @NonNull String tag, @NonNull INetworkStatsProvider provider,
+                @NonNull Semaphore semaphore,
+                @NonNull AlertObserver alertObserver,
+                @NonNull CopyOnWriteArrayList<NetworkStatsProviderCallbackImpl> cbList,
+                @NonNull NetworkPolicyManager networkPolicyManager)
+                throws RemoteException {
+            mTag = tag;
+            mProvider = provider;
+            mProvider.asBinder().linkToDeath(this, 0);
+            mSemaphore = semaphore;
+            mAlertObserver = alertObserver;
+            mStatsProviderCbList = cbList;
+            mNetworkPolicyManager = networkPolicyManager;
+        }
+
+        @NonNull
+        public NetworkStats getCachedStats(int how) {
+            synchronized (mProviderStatsLock) {
+                NetworkStats stats;
+                switch (how) {
+                    case STATS_PER_IFACE:
+                        stats = mIfaceStats;
+                        break;
+                    case STATS_PER_UID:
+                        stats = mUidStats;
+                        break;
+                    default:
+                        throw new IllegalArgumentException("Invalid type: " + how);
+                }
+                // Callers might be able to mutate the returned object. Return a defensive copy
+                // instead of local reference.
+                return stats.clone();
+            }
+        }
+
+        @Override
+        public void notifyStatsUpdated(int token, @Nullable NetworkStats ifaceStats,
+                @Nullable NetworkStats uidStats) {
+            // TODO: 1. Use token to map ifaces to correct NetworkIdentity.
+            //       2. Store the difference and store it directly to the recorder.
+            synchronized (mProviderStatsLock) {
+                if (ifaceStats != null) mIfaceStats.combineAllValues(ifaceStats);
+                if (uidStats != null) mUidStats.combineAllValues(uidStats);
+            }
+            mSemaphore.release();
+        }
+
+        @Override
+        public void notifyAlertReached() throws RemoteException {
+            // This binder object can only have been obtained by a process that holds
+            // NETWORK_STATS_PROVIDER. Thus, no additional permission check is required.
+            BinderUtils.withCleanCallingIdentity(() ->
+                    mAlertObserver.onQuotaLimitReached(LIMIT_GLOBAL_ALERT, null /* unused */));
+        }
+
+        @Override
+        public void notifyWarningReached() {
+            Log.d(TAG, mTag + ": notifyWarningReached");
+            BinderUtils.withCleanCallingIdentity(() ->
+                    mNetworkPolicyManager.notifyStatsProviderWarningReached());
+        }
+
+        @Override
+        public void notifyLimitReached() {
+            Log.d(TAG, mTag + ": notifyLimitReached");
+            BinderUtils.withCleanCallingIdentity(() ->
+                    mNetworkPolicyManager.notifyStatsProviderLimitReached());
+        }
+
+        @Override
+        public void binderDied() {
+            Log.d(TAG, mTag + ": binderDied");
+            mStatsProviderCbList.remove(this);
+        }
+
+        @Override
+        public void unregister() {
+            Log.d(TAG, mTag + ": unregister");
+            mStatsProviderCbList.remove(this);
+        }
+
+    }
+
+    private void assertSystemReady() {
+        if (!mSystemReady) {
+            throw new IllegalStateException("System not ready");
+        }
+    }
+
+    private class DropBoxNonMonotonicObserver implements NonMonotonicObserver<String> {
+        @Override
+        public void foundNonMonotonic(NetworkStats left, int leftIndex, NetworkStats right,
+                int rightIndex, String cookie) {
+            Log.w(TAG, "Found non-monotonic values; saving to dropbox");
+
+            // record error for debugging
+            final StringBuilder builder = new StringBuilder();
+            builder.append("found non-monotonic " + cookie + " values at left[" + leftIndex
+                    + "] - right[" + rightIndex + "]\n");
+            builder.append("left=").append(left).append('\n');
+            builder.append("right=").append(right).append('\n');
+
+            mContext.getSystemService(DropBoxManager.class).addText(TAG_NETSTATS_ERROR,
+                    builder.toString());
+        }
+
+        @Override
+        public void foundNonMonotonic(
+                NetworkStats stats, int statsIndex, String cookie) {
+            Log.w(TAG, "Found non-monotonic values; saving to dropbox");
+
+            final StringBuilder builder = new StringBuilder();
+            builder.append("Found non-monotonic " + cookie + " values at [" + statsIndex + "]\n");
+            builder.append("stats=").append(stats).append('\n');
+
+            mContext.getSystemService(DropBoxManager.class).addText(TAG_NETSTATS_ERROR,
+                    builder.toString());
+        }
+    }
+
+    /**
+     * Default external settings that read from
+     * {@link android.provider.Settings.Global}.
+     */
+    private static class DefaultNetworkStatsSettings implements NetworkStatsSettings {
+        DefaultNetworkStatsSettings() {}
+
+        @Override
+        public long getPollInterval() {
+            return 30 * MINUTE_IN_MILLIS;
+        }
+        @Override
+        public long getPollDelay() {
+            return DEFAULT_PERFORM_POLL_DELAY_MS;
+        }
+        @Override
+        public long getGlobalAlertBytes(long def) {
+            return def;
+        }
+        @Override
+        public boolean getSampleEnabled() {
+            return true;
+        }
+        @Override
+        public boolean getAugmentEnabled() {
+            return true;
+        }
+        @Override
+        public boolean getCombineSubtypeEnabled() {
+            return false;
+        }
+        @Override
+        public Config getDevConfig() {
+            return new Config(HOUR_IN_MILLIS, 15 * DAY_IN_MILLIS, 90 * DAY_IN_MILLIS);
+        }
+        @Override
+        public Config getXtConfig() {
+            return getDevConfig();
+        }
+        @Override
+        public Config getUidConfig() {
+            return new Config(2 * HOUR_IN_MILLIS, 15 * DAY_IN_MILLIS, 90 * DAY_IN_MILLIS);
+        }
+        @Override
+        public Config getUidTagConfig() {
+            return new Config(2 * HOUR_IN_MILLIS, 5 * DAY_IN_MILLIS, 15 * DAY_IN_MILLIS);
+        }
+        @Override
+        public long getDevPersistBytes(long def) {
+            return def;
+        }
+        @Override
+        public long getXtPersistBytes(long def) {
+            return def;
+        }
+        @Override
+        public long getUidPersistBytes(long def) {
+            return def;
+        }
+        @Override
+        public long getUidTagPersistBytes(long def) {
+            return def;
+        }
+    }
+
+    private static native long nativeGetTotalStat(int type);
+    private static native long nativeGetIfaceStat(String iface, int type);
+    private static native long nativeGetUidStat(int uid, int type);
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsSubscriptionsMonitor.java b/service-t/src/com/android/server/net/NetworkStatsSubscriptionsMonitor.java
new file mode 100644
index 0000000..65ccd20
--- /dev/null
+++ b/service-t/src/com/android/server/net/NetworkStatsSubscriptionsMonitor.java
@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static android.app.usage.NetworkStatsManager.NETWORK_TYPE_5G_NSA;
+import static android.app.usage.NetworkStatsManager.getCollapsedRatType;
+import static android.telephony.TelephonyDisplayInfo.OVERRIDE_NETWORK_TYPE_NR_ADVANCED;
+import static android.telephony.TelephonyDisplayInfo.OVERRIDE_NETWORK_TYPE_NR_NSA;
+import static android.telephony.TelephonyManager.NETWORK_TYPE_LTE;
+
+import android.annotation.NonNull;
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.os.Build;
+import android.telephony.SubscriptionManager;
+import android.telephony.TelephonyCallback;
+import android.telephony.TelephonyDisplayInfo;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.Log;
+import android.util.Pair;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.CollectionUtils;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executor;
+
+/**
+ * Helper class that watches for events that are triggered per subscription.
+ */
+@TargetApi(Build.VERSION_CODES.TIRAMISU)
+public class NetworkStatsSubscriptionsMonitor extends
+        SubscriptionManager.OnSubscriptionsChangedListener {
+
+    /**
+     * Interface that this monitor uses to delegate event handling to NetworkStatsService.
+     */
+    public interface Delegate {
+        /**
+         * Notify that the collapsed RAT type has been changed for any subscription. The method
+         * will also be triggered for any existing sub when start and stop monitoring.
+         *
+         * @param subscriberId IMSI of the subscription.
+         * @param collapsedRatType collapsed RAT type.
+         *                     @see android.app.usage.NetworkStatsManager#getCollapsedRatType(int).
+         */
+        void onCollapsedRatTypeChanged(@NonNull String subscriberId, int collapsedRatType);
+    }
+    private final Delegate mDelegate;
+
+    /**
+     * Receivers that watches for {@link TelephonyDisplayInfo} changes for each subscription, to
+     * monitor the transitioning between Radio Access Technology(RAT) types for each sub.
+     */
+    @NonNull
+    private final CopyOnWriteArrayList<RatTypeListener> mRatListeners =
+            new CopyOnWriteArrayList<>();
+
+    @NonNull
+    private final SubscriptionManager mSubscriptionManager;
+    @NonNull
+    private final TelephonyManager mTeleManager;
+
+    @NonNull
+    private final Executor mExecutor;
+
+    NetworkStatsSubscriptionsMonitor(@NonNull Context context,
+            @NonNull Executor executor, @NonNull Delegate delegate) {
+        super();
+        mSubscriptionManager = (SubscriptionManager) context.getSystemService(
+                Context.TELEPHONY_SUBSCRIPTION_SERVICE);
+        mTeleManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
+        mExecutor = executor;
+        mDelegate = delegate;
+    }
+
+    @Override
+    public void onSubscriptionsChanged() {
+        // Collect active subId list, hidden subId such as opportunistic subscriptions are
+        // also needed to track CBRS.
+        final List<Integer> newSubs = getActiveSubIdList(mSubscriptionManager);
+
+        // IMSI is needed for every newly added sub. Listener stores subscriberId into it to
+        // prevent binder call to telephony when querying RAT. Keep listener registration with empty
+        // IMSI is meaningless since the RAT type changed is ambiguous for multi-SIM if reported
+        // with empty IMSI. So filter the subs w/o a valid IMSI to prevent such registration.
+        final List<Pair<Integer, String>> filteredNewSubs = new ArrayList<>();
+        for (final int subId : newSubs) {
+            final String subscriberId =
+                    mTeleManager.createForSubscriptionId(subId).getSubscriberId();
+            if (!TextUtils.isEmpty(subscriberId)) {
+                filteredNewSubs.add(new Pair(subId, subscriberId));
+            }
+        }
+
+        for (final Pair<Integer, String> sub : filteredNewSubs) {
+            // Fully match listener with subId and IMSI, since in some rare cases, IMSI might be
+            // suddenly change regardless of subId, such as switch IMSI feature in modem side.
+            // If that happens, register new listener with new IMSI and remove old one later.
+            if (CollectionUtils.any(mRatListeners, it -> it.equalsKey(sub.first, sub.second))) {
+                continue;
+            }
+
+            final RatTypeListener listener = new RatTypeListener(this, sub.first, sub.second);
+            mRatListeners.add(listener);
+
+            // Register listener to the telephony manager that associated with specific sub.
+            mTeleManager.createForSubscriptionId(sub.first)
+                    .registerTelephonyCallback(mExecutor, listener);
+            Log.d(NetworkStatsService.TAG, "RAT type listener registered for sub " + sub.first);
+        }
+
+        for (final RatTypeListener listener : new ArrayList<>(mRatListeners)) {
+            // If there is no subId and IMSI matched the listener, removes it.
+            if (!CollectionUtils.any(filteredNewSubs,
+                    it -> listener.equalsKey(it.first, it.second))) {
+                handleRemoveRatTypeListener(listener);
+            }
+        }
+    }
+
+    @NonNull
+    private List<Integer> getActiveSubIdList(@NonNull SubscriptionManager subscriptionManager) {
+        final ArrayList<Integer> ret = new ArrayList<>();
+        final int[] ids = subscriptionManager.getCompleteActiveSubscriptionIdList();
+        for (int id : ids) ret.add(id);
+        return ret;
+    }
+
+    /**
+     * Get a collapsed RatType for the given subscriberId.
+     *
+     * @param subscriberId the target subscriberId
+     * @return collapsed RatType for the given subscriberId
+     */
+    public int getRatTypeForSubscriberId(@NonNull String subscriberId) {
+        final int index = CollectionUtils.indexOf(mRatListeners,
+                it -> TextUtils.equals(subscriberId, it.mSubscriberId));
+        return index != -1 ? mRatListeners.get(index).mLastCollapsedRatType
+                : TelephonyManager.NETWORK_TYPE_UNKNOWN;
+    }
+
+    /**
+     * Start monitoring events that triggered per subscription.
+     */
+    public void start() {
+        mSubscriptionManager.addOnSubscriptionsChangedListener(mExecutor, this);
+    }
+
+    /**
+     * Unregister subscription changes and all listeners for each subscription.
+     */
+    public void stop() {
+        mSubscriptionManager.removeOnSubscriptionsChangedListener(this);
+
+        for (final RatTypeListener listener : new ArrayList<>(mRatListeners)) {
+            handleRemoveRatTypeListener(listener);
+        }
+    }
+
+    private void handleRemoveRatTypeListener(@NonNull RatTypeListener listener) {
+        mTeleManager.createForSubscriptionId(listener.mSubId)
+                .unregisterTelephonyCallback(listener);
+        Log.d(NetworkStatsService.TAG, "RAT type listener unregistered for sub " + listener.mSubId);
+        mRatListeners.remove(listener);
+
+        // Removal of subscriptions doesn't generate RAT changed event, fire it for every
+        // RatTypeListener.
+        mDelegate.onCollapsedRatTypeChanged(
+                listener.mSubscriberId, TelephonyManager.NETWORK_TYPE_UNKNOWN);
+    }
+
+    static class RatTypeListener extends TelephonyCallback
+            implements TelephonyCallback.DisplayInfoListener {
+        // Unique id for the subscription. See {@link SubscriptionInfo#getSubscriptionId}.
+        @NonNull
+        private final int mSubId;
+
+        // IMSI to identifying the corresponding network from {@link NetworkState}.
+        // See {@link TelephonyManager#getSubscriberId}.
+        @NonNull
+        private final String mSubscriberId;
+
+        private volatile int mLastCollapsedRatType = TelephonyManager.NETWORK_TYPE_UNKNOWN;
+        @NonNull
+        private final NetworkStatsSubscriptionsMonitor mMonitor;
+
+        RatTypeListener(@NonNull NetworkStatsSubscriptionsMonitor monitor, int subId,
+                @NonNull String subscriberId) {
+            mSubId = subId;
+            mSubscriberId = subscriberId;
+            mMonitor = monitor;
+        }
+
+        @Override
+        public void onDisplayInfoChanged(TelephonyDisplayInfo displayInfo) {
+            // In 5G SA (Stand Alone) mode, the primary cell itself will be 5G hence telephony
+            // would report RAT = 5G_NR.
+            // However, in 5G NSA (Non Stand Alone) mode, the primary cell is still LTE and
+            // network allocates a secondary 5G cell so telephony reports RAT = LTE along with
+            // NR state as connected. In such case, attributes the data usage to NR.
+            // See b/160727498.
+            final boolean is5GNsa = displayInfo.getNetworkType() == NETWORK_TYPE_LTE
+                    && (displayInfo.getOverrideNetworkType() == OVERRIDE_NETWORK_TYPE_NR_NSA
+                    || displayInfo.getOverrideNetworkType() == OVERRIDE_NETWORK_TYPE_NR_ADVANCED);
+
+            final int networkType =
+                    (is5GNsa ? NETWORK_TYPE_5G_NSA : displayInfo.getNetworkType());
+            final int collapsedRatType = getCollapsedRatType(networkType);
+            if (collapsedRatType == mLastCollapsedRatType) return;
+
+            if (NetworkStatsService.LOGD) {
+                Log.d(NetworkStatsService.TAG, "subtype changed for sub(" + mSubId + "): "
+                        + mLastCollapsedRatType + " -> " + collapsedRatType);
+            }
+            mLastCollapsedRatType = collapsedRatType;
+            mMonitor.mDelegate.onCollapsedRatTypeChanged(mSubscriberId, mLastCollapsedRatType);
+        }
+
+        @VisibleForTesting
+        public int getSubId() {
+            return mSubId;
+        }
+
+        boolean equalsKey(int subId, @NonNull String subscriberId) {
+            return mSubId == subId && TextUtils.equals(mSubscriberId, subscriberId);
+        }
+    }
+}
diff --git a/service-t/src/com/android/server/net/StatsMapKey.java b/service-t/src/com/android/server/net/StatsMapKey.java
new file mode 100644
index 0000000..ea8d836
--- /dev/null
+++ b/service-t/src/com/android/server/net/StatsMapKey.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * Key for both stats maps.
+ */
+public class StatsMapKey extends Struct {
+    @Field(order = 0, type = Type.U32)
+    public final long uid;
+
+    @Field(order = 1, type = Type.U32)
+    public final long tag;
+
+    @Field(order = 2, type = Type.U32)
+    public final long counterSet;
+
+    @Field(order = 3, type = Type.U32)
+    public final long ifaceIndex;
+
+    public StatsMapKey(final long uid, final long tag, final long counterSet,
+            final long ifaceIndex) {
+        this.uid = uid;
+        this.tag = tag;
+        this.counterSet = counterSet;
+        this.ifaceIndex = ifaceIndex;
+    }
+}
diff --git a/service-t/src/com/android/server/net/StatsMapValue.java b/service-t/src/com/android/server/net/StatsMapValue.java
new file mode 100644
index 0000000..48f26ce
--- /dev/null
+++ b/service-t/src/com/android/server/net/StatsMapValue.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * Value used for both stats maps and uid stats map.
+ */
+public class StatsMapValue extends Struct {
+    @Field(order = 0, type = Type.U63)
+    public final long rxPackets;
+
+    @Field(order = 1, type = Type.U63)
+    public final long rxBytes;
+
+    @Field(order = 2, type = Type.U63)
+    public final long txPackets;
+
+    @Field(order = 3, type = Type.U63)
+    public final long txBytes;
+
+    public StatsMapValue(final long rxPackets, final long rxBytes, final long txPackets,
+            final long txBytes) {
+        this.rxPackets = rxPackets;
+        this.rxBytes = rxBytes;
+        this.txPackets = txPackets;
+        this.txBytes = txBytes;
+    }
+}
diff --git a/service-t/src/com/android/server/net/UidStatsMapKey.java b/service-t/src/com/android/server/net/UidStatsMapKey.java
new file mode 100644
index 0000000..2849f94
--- /dev/null
+++ b/service-t/src/com/android/server/net/UidStatsMapKey.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import com.android.net.module.util.Struct;
+import com.android.net.module.util.Struct.Field;
+import com.android.net.module.util.Struct.Type;
+
+/**
+ * Key for uid stats map.
+ */
+public class UidStatsMapKey extends Struct {
+    @Field(order = 0, type = Type.U32)
+    public final long uid;
+
+    public UidStatsMapKey(final long uid) {
+        this.uid = uid;
+    }
+}
diff --git a/service/src/com/android/server/net/DelayedDiskWrite.java b/service/src/com/android/server/net/DelayedDiskWrite.java
new file mode 100644
index 0000000..35dc455
--- /dev/null
+++ b/service/src/com/android/server/net/DelayedDiskWrite.java
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.text.TextUtils;
+import android.util.Log;
+
+import java.io.BufferedOutputStream;
+import java.io.DataOutputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+/**
+ * This class provides APIs to do a delayed data write to a given {@link OutputStream}.
+ */
+public class DelayedDiskWrite {
+    private static final String TAG = "DelayedDiskWrite";
+
+    private HandlerThread mDiskWriteHandlerThread;
+    private Handler mDiskWriteHandler;
+    /* Tracks multiple writes on the same thread */
+    private int mWriteSequence = 0;
+
+    /**
+     * Used to do a delayed data write to a given {@link OutputStream}.
+     */
+    public interface Writer {
+        /**
+         * write data to a given {@link OutputStream}.
+         */
+        void onWriteCalled(DataOutputStream out) throws IOException;
+    }
+
+    /**
+     * Do a delayed data write to a given output stream opened from filePath.
+     */
+    public void write(final String filePath, final Writer w) {
+        write(filePath, w, true);
+    }
+
+    /**
+     * Do a delayed data write to a given output stream opened from filePath.
+     */
+    public void write(final String filePath, final Writer w, final boolean open) {
+        if (TextUtils.isEmpty(filePath)) {
+            throw new IllegalArgumentException("empty file path");
+        }
+
+        /* Do a delayed write to disk on a separate handler thread */
+        synchronized (this) {
+            if (++mWriteSequence == 1) {
+                mDiskWriteHandlerThread = new HandlerThread("DelayedDiskWriteThread");
+                mDiskWriteHandlerThread.start();
+                mDiskWriteHandler = new Handler(mDiskWriteHandlerThread.getLooper());
+            }
+        }
+
+        mDiskWriteHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                doWrite(filePath, w, open);
+            }
+        });
+    }
+
+    private void doWrite(String filePath, Writer w, boolean open) {
+        DataOutputStream out = null;
+        try {
+            if (open) {
+                out = new DataOutputStream(new BufferedOutputStream(
+                        new FileOutputStream(filePath)));
+            }
+            w.onWriteCalled(out);
+        } catch (IOException e) {
+            loge("Error writing data file " + filePath);
+        } finally {
+            if (out != null) {
+                try {
+                    out.close();
+                } catch (Exception e) { }
+            }
+
+            // Quit if no more writes sent
+            synchronized (this) {
+                if (--mWriteSequence == 0) {
+                    mDiskWriteHandler.getLooper().quit();
+                    mDiskWriteHandler = null;
+                    mDiskWriteHandlerThread = null;
+                }
+            }
+        }
+    }
+
+    private void loge(String s) {
+        Log.e(TAG, s);
+    }
+}
+
diff --git a/tests/unit/Android.bp b/tests/unit/Android.bp
index 901251c..0e5fa54 100644
--- a/tests/unit/Android.bp
+++ b/tests/unit/Android.bp
@@ -76,6 +76,7 @@
         "java/com/android/server/IpSecServiceParameterizedTest.java",
         "java/com/android/server/IpSecServiceRefcountedResourceTest.java",
         "java/com/android/server/IpSecServiceTest.java",
+        "java/com/android/server/NativeDaemonConnectorTest.java",
         "java/com/android/server/NetworkManagementServiceTest.java",
         "java/com/android/server/NsdServiceTest.java",
         "java/com/android/server/connectivity/IpConnectivityEventBuilderTest.java",
@@ -83,8 +84,10 @@
         "java/com/android/server/connectivity/MultipathPolicyTrackerTest.java",
         "java/com/android/server/connectivity/NetdEventListenerServiceTest.java",
         "java/com/android/server/connectivity/VpnTest.java",
+        "java/com/android/server/ethernet/*.java",
         "java/com/android/server/net/ipmemorystore/*.java",
         "java/com/android/server/net/BpfInterfaceMapUpdaterTest.java",
+        "java/com/android/server/net/IpConfigStoreTest.java",
         "java/com/android/server/net/NetworkStats*.java",
         "java/com/android/server/net/TestableUsageCallback.kt",
     ]
diff --git a/tests/unit/java/com/android/server/NativeDaemonConnectorTest.java b/tests/unit/java/com/android/server/NativeDaemonConnectorTest.java
new file mode 100644
index 0000000..e2253a2
--- /dev/null
+++ b/tests/unit/java/com/android/server/NativeDaemonConnectorTest.java
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server;
+
+import static com.android.server.NativeDaemonConnector.appendEscaped;
+import static com.android.server.NativeDaemonConnector.makeCommand;
+
+import android.test.AndroidTestCase;
+import android.test.suitebuilder.annotation.MediumTest;
+
+import com.android.server.NativeDaemonConnector.SensitiveArg;
+
+/**
+ * Tests for {@link NativeDaemonConnector}.
+ */
+@MediumTest
+public class NativeDaemonConnectorTest extends AndroidTestCase {
+    private static final String TAG = "NativeDaemonConnectorTest";
+
+    public void testArgumentNormal() throws Exception {
+        final StringBuilder builder = new StringBuilder();
+
+        builder.setLength(0);
+        appendEscaped(builder, "");
+        assertEquals("", builder.toString());
+
+        builder.setLength(0);
+        appendEscaped(builder, "foo");
+        assertEquals("foo", builder.toString());
+
+        builder.setLength(0);
+        appendEscaped(builder, "foo\"bar");
+        assertEquals("foo\\\"bar", builder.toString());
+
+        builder.setLength(0);
+        appendEscaped(builder, "foo\\bar\\\"baz");
+        assertEquals("foo\\\\bar\\\\\\\"baz", builder.toString());
+    }
+
+    public void testArgumentWithSpaces() throws Exception {
+        final StringBuilder builder = new StringBuilder();
+
+        builder.setLength(0);
+        appendEscaped(builder, "foo bar");
+        assertEquals("\"foo bar\"", builder.toString());
+
+        builder.setLength(0);
+        appendEscaped(builder, "foo\"bar\\baz foo");
+        assertEquals("\"foo\\\"bar\\\\baz foo\"", builder.toString());
+    }
+
+    public void testArgumentWithUtf() throws Exception {
+        final StringBuilder builder = new StringBuilder();
+
+        builder.setLength(0);
+        appendEscaped(builder, "caf\u00E9 c\u00F6ffee");
+        assertEquals("\"caf\u00E9 c\u00F6ffee\"", builder.toString());
+    }
+
+    public void testSensitiveArgs() throws Exception {
+        final StringBuilder rawBuilder = new StringBuilder();
+        final StringBuilder logBuilder = new StringBuilder();
+
+        rawBuilder.setLength(0);
+        logBuilder.setLength(0);
+        makeCommand(rawBuilder, logBuilder, 1, "foo", "bar", "baz");
+        assertEquals("1 foo bar baz\0", rawBuilder.toString());
+        assertEquals("1 foo bar baz", logBuilder.toString());
+
+        rawBuilder.setLength(0);
+        logBuilder.setLength(0);
+        makeCommand(rawBuilder, logBuilder, 1, "foo", new SensitiveArg("bar"), "baz");
+        assertEquals("1 foo bar baz\0", rawBuilder.toString());
+        assertEquals("1 foo [scrubbed] baz", logBuilder.toString());
+
+        rawBuilder.setLength(0);
+        logBuilder.setLength(0);
+        makeCommand(rawBuilder, logBuilder, 1, "foo", new SensitiveArg("foo bar"), "baz baz",
+                new SensitiveArg("wat"));
+        assertEquals("1 foo \"foo bar\" \"baz baz\" wat\0", rawBuilder.toString());
+        assertEquals("1 foo [scrubbed] \"baz baz\" [scrubbed]", logBuilder.toString());
+    }
+}
diff --git a/tests/unit/java/com/android/server/ethernet/EthernetNetworkFactoryTest.java b/tests/unit/java/com/android/server/ethernet/EthernetNetworkFactoryTest.java
new file mode 100644
index 0000000..4d3e4d3
--- /dev/null
+++ b/tests/unit/java/com/android/server/ethernet/EthernetNetworkFactoryTest.java
@@ -0,0 +1,783 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import static com.android.testutils.DevSdkIgnoreRuleKt.SC_V2;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.argThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.same;
+import static org.mockito.Mockito.clearInvocations;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.annotation.NonNull;
+import android.app.test.MockAnswerUtil.AnswerWithArguments;
+import android.content.Context;
+import android.content.res.Resources;
+import android.net.ConnectivityManager;
+import android.net.EthernetNetworkSpecifier;
+import android.net.EthernetNetworkManagementException;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.IpConfiguration;
+import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.Network;
+import android.net.NetworkAgentConfig;
+import android.net.NetworkCapabilities;
+import android.net.NetworkProvider;
+import android.net.NetworkRequest;
+import android.net.StaticIpConfiguration;
+import android.net.ip.IpClientCallbacks;
+import android.net.ip.IpClientManager;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Looper;
+import android.os.test.TestLooper;
+import android.util.Pair;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.connectivity.resources.R;
+import com.android.net.module.util.InterfaceParams;
+
+import com.android.testutils.DevSdkIgnoreRule;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+import java.util.Objects;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
+
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class EthernetNetworkFactoryTest {
+    private static final int TIMEOUT_MS = 2_000;
+    private static final String TEST_IFACE = "test123";
+    private static final INetworkInterfaceOutcomeReceiver NULL_LISTENER = null;
+    private static final String IP_ADDR = "192.0.2.2/25";
+    private static final LinkAddress LINK_ADDR = new LinkAddress(IP_ADDR);
+    private static final String HW_ADDR = "01:02:03:04:05:06";
+    private TestLooper mLooper;
+    private Handler mHandler;
+    private EthernetNetworkFactory mNetFactory = null;
+    private IpClientCallbacks mIpClientCallbacks;
+    @Mock private Context mContext;
+    @Mock private Resources mResources;
+    @Mock private EthernetNetworkFactory.Dependencies mDeps;
+    @Mock private IpClientManager mIpClient;
+    @Mock private EthernetNetworkAgent mNetworkAgent;
+    @Mock private InterfaceParams mInterfaceParams;
+    @Mock private Network mMockNetwork;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        setupNetworkAgentMock();
+        setupIpClientMock();
+        setupContext();
+    }
+
+    //TODO: Move away from usage of TestLooper in order to move this logic back into @Before.
+    private void initEthernetNetworkFactory() {
+        mLooper = new TestLooper();
+        mHandler = new Handler(mLooper.getLooper());
+        mNetFactory = new EthernetNetworkFactory(mHandler, mContext, mDeps);
+    }
+
+    private void setupNetworkAgentMock() {
+        when(mDeps.makeEthernetNetworkAgent(any(), any(), any(), any(), any(), any(), any()))
+                .thenAnswer(new AnswerWithArguments() {
+                                       public EthernetNetworkAgent answer(
+                                               Context context,
+                                               Looper looper,
+                                               NetworkCapabilities nc,
+                                               LinkProperties lp,
+                                               NetworkAgentConfig config,
+                                               NetworkProvider provider,
+                                               EthernetNetworkAgent.Callbacks cb) {
+                                           when(mNetworkAgent.getCallbacks()).thenReturn(cb);
+                                           when(mNetworkAgent.getNetwork())
+                                                   .thenReturn(mMockNetwork);
+                                           return mNetworkAgent;
+                                       }
+                                   }
+        );
+    }
+
+    private void setupIpClientMock() throws Exception {
+        doAnswer(inv -> {
+            // these tests only support one concurrent IpClient, so make sure we do not accidentally
+            // create a mess.
+            assertNull("An IpClient has already been created.", mIpClientCallbacks);
+
+            mIpClientCallbacks = inv.getArgument(2);
+            mIpClientCallbacks.onIpClientCreated(null);
+            mLooper.dispatchAll();
+            return null;
+        }).when(mDeps).makeIpClient(any(Context.class), anyString(), any());
+
+        doAnswer(inv -> {
+            mIpClientCallbacks.onQuit();
+            mLooper.dispatchAll();
+            mIpClientCallbacks = null;
+            return null;
+        }).when(mIpClient).shutdown();
+
+        when(mDeps.makeIpClientManager(any())).thenReturn(mIpClient);
+    }
+
+    private void triggerOnProvisioningSuccess() {
+        mIpClientCallbacks.onProvisioningSuccess(new LinkProperties());
+        mLooper.dispatchAll();
+    }
+
+    private void triggerOnProvisioningFailure() {
+        mIpClientCallbacks.onProvisioningFailure(new LinkProperties());
+        mLooper.dispatchAll();
+    }
+
+    private void triggerOnReachabilityLost() {
+        mIpClientCallbacks.onReachabilityLost("ReachabilityLost");
+        mLooper.dispatchAll();
+    }
+
+    private void setupContext() {
+        when(mDeps.getTcpBufferSizesFromResource(eq(mContext))).thenReturn("");
+    }
+
+    @After
+    public void tearDown() {
+        // looper is shared with the network agents, so there may still be messages to dispatch on
+        // tear down.
+        mLooper.dispatchAll();
+    }
+
+    private NetworkCapabilities createDefaultFilterCaps() {
+        return NetworkCapabilities.Builder.withoutDefaultCapabilities()
+                .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                .build();
+    }
+
+    private NetworkCapabilities.Builder createInterfaceCapsBuilder(final int transportType) {
+        return new NetworkCapabilities.Builder()
+                .addTransportType(transportType)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VCN_MANAGED);
+    }
+
+    private NetworkRequest.Builder createDefaultRequestBuilder() {
+        return new NetworkRequest.Builder()
+                .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+    }
+
+    private NetworkRequest createDefaultRequest() {
+        return createDefaultRequestBuilder().build();
+    }
+
+    private IpConfiguration createDefaultIpConfig() {
+        IpConfiguration ipConfig = new IpConfiguration();
+        ipConfig.setIpAssignment(IpConfiguration.IpAssignment.DHCP);
+        ipConfig.setProxySettings(IpConfiguration.ProxySettings.NONE);
+        return ipConfig;
+    }
+
+    /**
+     * Create an {@link IpConfiguration} with an associated {@link StaticIpConfiguration}.
+     *
+     * @return {@link IpConfiguration} with its {@link StaticIpConfiguration} set.
+     */
+    private IpConfiguration createStaticIpConfig() {
+        final IpConfiguration ipConfig = new IpConfiguration();
+        ipConfig.setIpAssignment(IpConfiguration.IpAssignment.STATIC);
+        ipConfig.setStaticIpConfiguration(
+                new StaticIpConfiguration.Builder().setIpAddress(LINK_ADDR).build());
+        return ipConfig;
+    }
+
+    // creates an interface with provisioning in progress (since updating the interface link state
+    // automatically starts the provisioning process)
+    private void createInterfaceUndergoingProvisioning(String iface) {
+        // Default to the ethernet transport type.
+        createInterfaceUndergoingProvisioning(iface, NetworkCapabilities.TRANSPORT_ETHERNET);
+    }
+
+    private void createInterfaceUndergoingProvisioning(
+            @NonNull final String iface, final int transportType) {
+        final IpConfiguration ipConfig = createDefaultIpConfig();
+        mNetFactory.addInterface(iface, HW_ADDR, ipConfig,
+                createInterfaceCapsBuilder(transportType).build());
+        assertTrue(mNetFactory.updateInterfaceLinkState(iface, true, NULL_LISTENER));
+        verifyStart(ipConfig);
+        clearInvocations(mDeps);
+        clearInvocations(mIpClient);
+    }
+
+    // creates a provisioned interface
+    private void createAndVerifyProvisionedInterface(String iface) throws Exception {
+        // Default to the ethernet transport type.
+        createAndVerifyProvisionedInterface(iface, NetworkCapabilities.TRANSPORT_ETHERNET,
+                ConnectivityManager.TYPE_ETHERNET);
+    }
+
+    private void createVerifyAndRemoveProvisionedInterface(final int transportType,
+            final int expectedLegacyType) throws Exception {
+        createAndVerifyProvisionedInterface(TEST_IFACE, transportType,
+                expectedLegacyType);
+        mNetFactory.removeInterface(TEST_IFACE);
+    }
+
+    private void createAndVerifyProvisionedInterface(
+            @NonNull final String iface, final int transportType, final int expectedLegacyType)
+            throws Exception {
+        createInterfaceUndergoingProvisioning(iface, transportType);
+        triggerOnProvisioningSuccess();
+        // provisioning succeeded, verify that the network agent is created, registered, marked
+        // as connected and legacy type are correctly set.
+        final ArgumentCaptor<NetworkCapabilities> ncCaptor = ArgumentCaptor.forClass(
+                NetworkCapabilities.class);
+        verify(mDeps).makeEthernetNetworkAgent(any(), any(), ncCaptor.capture(), any(),
+                argThat(x -> x.getLegacyType() == expectedLegacyType), any(), any());
+        assertEquals(
+                new EthernetNetworkSpecifier(iface), ncCaptor.getValue().getNetworkSpecifier());
+        verifyNetworkAgentRegistersAndConnects();
+        clearInvocations(mDeps);
+        clearInvocations(mNetworkAgent);
+    }
+
+    // creates an unprovisioned interface
+    private void createUnprovisionedInterface(String iface) throws Exception {
+        // To create an unprovisioned interface, provision and then "stop" it, i.e. stop its
+        // NetworkAgent and IpClient. One way this can be done is by provisioning an interface and
+        // then calling onNetworkUnwanted.
+        createAndVerifyProvisionedInterface(iface);
+
+        mNetworkAgent.getCallbacks().onNetworkUnwanted();
+        mLooper.dispatchAll();
+        verifyStop();
+
+        clearInvocations(mIpClient);
+        clearInvocations(mNetworkAgent);
+    }
+
+    @Test
+    public void testAcceptRequest() throws Exception {
+        initEthernetNetworkFactory();
+        createInterfaceUndergoingProvisioning(TEST_IFACE);
+        assertTrue(mNetFactory.acceptRequest(createDefaultRequest()));
+
+        NetworkRequest wifiRequest = createDefaultRequestBuilder()
+                .removeTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                .addTransportType(NetworkCapabilities.TRANSPORT_WIFI).build();
+        assertFalse(mNetFactory.acceptRequest(wifiRequest));
+    }
+
+    @Test
+    public void testUpdateInterfaceLinkStateForActiveProvisioningInterface() throws Exception {
+        initEthernetNetworkFactory();
+        createInterfaceUndergoingProvisioning(TEST_IFACE);
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        // verify that the IpClient gets shut down when interface state changes to down.
+        final boolean ret =
+                mNetFactory.updateInterfaceLinkState(TEST_IFACE, false /* up */, listener);
+
+        assertTrue(ret);
+        verify(mIpClient).shutdown();
+        assertEquals(listener.expectOnResult(), TEST_IFACE);
+    }
+
+    @Test
+    public void testUpdateInterfaceLinkStateForProvisionedInterface() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        final boolean ret =
+                mNetFactory.updateInterfaceLinkState(TEST_IFACE, false /* up */, listener);
+
+        assertTrue(ret);
+        verifyStop();
+        assertEquals(listener.expectOnResult(), TEST_IFACE);
+    }
+
+    @Test
+    public void testUpdateInterfaceLinkStateForUnprovisionedInterface() throws Exception {
+        initEthernetNetworkFactory();
+        createUnprovisionedInterface(TEST_IFACE);
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        final boolean ret =
+                mNetFactory.updateInterfaceLinkState(TEST_IFACE, false /* up */, listener);
+
+        assertTrue(ret);
+        // There should not be an active IPClient or NetworkAgent.
+        verify(mDeps, never()).makeIpClient(any(), any(), any());
+        verify(mDeps, never())
+                .makeEthernetNetworkAgent(any(), any(), any(), any(), any(), any(), any());
+        assertEquals(listener.expectOnResult(), TEST_IFACE);
+    }
+
+    @Test
+    public void testUpdateInterfaceLinkStateForNonExistingInterface() throws Exception {
+        initEthernetNetworkFactory();
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        // if interface was never added, link state cannot be updated.
+        final boolean ret =
+                mNetFactory.updateInterfaceLinkState(TEST_IFACE, true /* up */, listener);
+
+        assertFalse(ret);
+        verifyNoStopOrStart();
+        listener.expectOnErrorWithMessage("can't be updated as it is not available");
+    }
+
+    @Test
+    public void testUpdateInterfaceLinkStateWithNoChanges() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        final boolean ret =
+                mNetFactory.updateInterfaceLinkState(TEST_IFACE, true /* up */, listener);
+
+        assertFalse(ret);
+        verifyNoStopOrStart();
+        listener.expectOnErrorWithMessage("No changes");
+    }
+
+    @Test
+    public void testNeedNetworkForOnProvisionedInterface() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        mNetFactory.needNetworkFor(createDefaultRequest());
+        verify(mIpClient, never()).startProvisioning(any());
+    }
+
+    @Test
+    public void testNeedNetworkForOnUnprovisionedInterface() throws Exception {
+        initEthernetNetworkFactory();
+        createUnprovisionedInterface(TEST_IFACE);
+        mNetFactory.needNetworkFor(createDefaultRequest());
+        verify(mIpClient).startProvisioning(any());
+
+        triggerOnProvisioningSuccess();
+        verifyNetworkAgentRegistersAndConnects();
+    }
+
+    @Test
+    public void testNeedNetworkForOnInterfaceUndergoingProvisioning() throws Exception {
+        initEthernetNetworkFactory();
+        createInterfaceUndergoingProvisioning(TEST_IFACE);
+        mNetFactory.needNetworkFor(createDefaultRequest());
+        verify(mIpClient, never()).startProvisioning(any());
+
+        triggerOnProvisioningSuccess();
+        verifyNetworkAgentRegistersAndConnects();
+    }
+
+    @Test
+    public void testProvisioningLoss() throws Exception {
+        initEthernetNetworkFactory();
+        when(mDeps.getNetworkInterfaceByName(TEST_IFACE)).thenReturn(mInterfaceParams);
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        triggerOnProvisioningFailure();
+        verifyStop();
+        // provisioning loss should trigger a retry, since the interface is still there
+        verify(mIpClient).startProvisioning(any());
+    }
+
+    @Test
+    public void testProvisioningLossForDisappearedInterface() throws Exception {
+        initEthernetNetworkFactory();
+        // mocked method returns null by default, but just to be explicit in the test:
+        when(mDeps.getNetworkInterfaceByName(eq(TEST_IFACE))).thenReturn(null);
+
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        triggerOnProvisioningFailure();
+
+        // the interface disappeared and getNetworkInterfaceByName returns null, we should not retry
+        verify(mIpClient, never()).startProvisioning(any());
+        verifyNoStopOrStart();
+    }
+
+    private void verifyNoStopOrStart() {
+        verify(mNetworkAgent, never()).register();
+        verify(mIpClient, never()).shutdown();
+        verify(mNetworkAgent, never()).unregister();
+        verify(mIpClient, never()).startProvisioning(any());
+    }
+
+    @Test
+    public void testIpClientIsNotStartedWhenLinkIsDown() throws Exception {
+        initEthernetNetworkFactory();
+        createUnprovisionedInterface(TEST_IFACE);
+        mNetFactory.updateInterfaceLinkState(TEST_IFACE, false, NULL_LISTENER);
+
+        mNetFactory.needNetworkFor(createDefaultRequest());
+
+        verify(mDeps, never()).makeIpClient(any(), any(), any());
+
+        // BUG(b/191854824): requesting a network with a specifier (Android Auto use case) should
+        // not start an IpClient when the link is down, but fixing this may make matters worse by
+        // tiggering b/197548738.
+        NetworkRequest specificNetRequest = new NetworkRequest.Builder()
+                .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                .setNetworkSpecifier(new EthernetNetworkSpecifier(TEST_IFACE))
+                .build();
+        mNetFactory.needNetworkFor(specificNetRequest);
+        mNetFactory.releaseNetworkFor(specificNetRequest);
+
+        mNetFactory.updateInterfaceLinkState(TEST_IFACE, true, NULL_LISTENER);
+        // TODO: change to once when b/191854824 is fixed.
+        verify(mDeps, times(2)).makeIpClient(any(), eq(TEST_IFACE), any());
+    }
+
+    @Test
+    public void testLinkPropertiesChanged() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        LinkProperties lp = new LinkProperties();
+        mIpClientCallbacks.onLinkPropertiesChange(lp);
+        mLooper.dispatchAll();
+        verify(mNetworkAgent).sendLinkPropertiesImpl(same(lp));
+    }
+
+    @Test
+    public void testNetworkUnwanted() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        mNetworkAgent.getCallbacks().onNetworkUnwanted();
+        mLooper.dispatchAll();
+        verifyStop();
+    }
+
+    @Test
+    public void testNetworkUnwantedWithStaleNetworkAgent() throws Exception {
+        initEthernetNetworkFactory();
+        // ensures provisioning is restarted after provisioning loss
+        when(mDeps.getNetworkInterfaceByName(TEST_IFACE)).thenReturn(mInterfaceParams);
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        EthernetNetworkAgent.Callbacks oldCbs = mNetworkAgent.getCallbacks();
+        // replace network agent in EthernetNetworkFactory
+        // Loss of provisioning will restart the ip client and network agent.
+        triggerOnProvisioningFailure();
+        verify(mDeps).makeIpClient(any(), any(), any());
+
+        triggerOnProvisioningSuccess();
+        verify(mDeps).makeEthernetNetworkAgent(any(), any(), any(), any(), any(), any(), any());
+
+        // verify that unwanted is ignored
+        clearInvocations(mIpClient);
+        clearInvocations(mNetworkAgent);
+        oldCbs.onNetworkUnwanted();
+        verify(mIpClient, never()).shutdown();
+        verify(mNetworkAgent, never()).unregister();
+    }
+
+    @Test
+    public void testTransportOverrideIsCorrectlySet() throws Exception {
+        initEthernetNetworkFactory();
+        // createProvisionedInterface() has verifications in place for transport override
+        // functionality which for EthernetNetworkFactory is network score and legacy type mappings.
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_ETHERNET,
+                ConnectivityManager.TYPE_ETHERNET);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_BLUETOOTH,
+                ConnectivityManager.TYPE_BLUETOOTH);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_WIFI,
+                ConnectivityManager.TYPE_WIFI);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_CELLULAR,
+                ConnectivityManager.TYPE_MOBILE);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_LOWPAN,
+                ConnectivityManager.TYPE_NONE);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_WIFI_AWARE,
+                ConnectivityManager.TYPE_NONE);
+        createVerifyAndRemoveProvisionedInterface(NetworkCapabilities.TRANSPORT_TEST,
+                ConnectivityManager.TYPE_NONE);
+    }
+
+    @Test
+    public void testReachabilityLoss() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        triggerOnReachabilityLost();
+
+        // Reachability loss should trigger a stop and start, since the interface is still there
+        verifyRestart(createDefaultIpConfig());
+    }
+
+    private IpClientCallbacks getStaleIpClientCallbacks() throws Exception {
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        final IpClientCallbacks staleIpClientCallbacks = mIpClientCallbacks;
+        mNetFactory.removeInterface(TEST_IFACE);
+        verifyStop();
+        assertNotSame(mIpClientCallbacks, staleIpClientCallbacks);
+        return staleIpClientCallbacks;
+    }
+
+    @Test
+    public void testIgnoreOnIpLayerStartedCallbackForStaleCallback() throws Exception {
+        initEthernetNetworkFactory();
+        final IpClientCallbacks staleIpClientCallbacks = getStaleIpClientCallbacks();
+
+        staleIpClientCallbacks.onProvisioningSuccess(new LinkProperties());
+        mLooper.dispatchAll();
+
+        verify(mIpClient, never()).startProvisioning(any());
+        verify(mNetworkAgent, never()).register();
+    }
+
+    @Test
+    public void testIgnoreOnIpLayerStoppedCallbackForStaleCallback() throws Exception {
+        initEthernetNetworkFactory();
+        when(mDeps.getNetworkInterfaceByName(TEST_IFACE)).thenReturn(mInterfaceParams);
+        final IpClientCallbacks staleIpClientCallbacks = getStaleIpClientCallbacks();
+
+        staleIpClientCallbacks.onProvisioningFailure(new LinkProperties());
+        mLooper.dispatchAll();
+
+        verify(mIpClient, never()).startProvisioning(any());
+    }
+
+    @Test
+    public void testIgnoreLinkPropertiesCallbackForStaleCallback() throws Exception {
+        initEthernetNetworkFactory();
+        final IpClientCallbacks staleIpClientCallbacks = getStaleIpClientCallbacks();
+        final LinkProperties lp = new LinkProperties();
+
+        staleIpClientCallbacks.onLinkPropertiesChange(lp);
+        mLooper.dispatchAll();
+
+        verify(mNetworkAgent, never()).sendLinkPropertiesImpl(eq(lp));
+    }
+
+    @Test
+    public void testIgnoreNeighborLossCallbackForStaleCallback() throws Exception {
+        initEthernetNetworkFactory();
+        final IpClientCallbacks staleIpClientCallbacks = getStaleIpClientCallbacks();
+
+        staleIpClientCallbacks.onReachabilityLost("Neighbor Lost");
+        mLooper.dispatchAll();
+
+        verify(mIpClient, never()).startProvisioning(any());
+        verify(mNetworkAgent, never()).register();
+    }
+
+    private void verifyRestart(@NonNull final IpConfiguration ipConfig) {
+        verifyStop();
+        verifyStart(ipConfig);
+    }
+
+    private void verifyStart(@NonNull final IpConfiguration ipConfig) {
+        verify(mDeps).makeIpClient(any(Context.class), anyString(), any());
+        verify(mIpClient).startProvisioning(
+                argThat(x -> Objects.equals(x.mStaticIpConfig, ipConfig.getStaticIpConfiguration()))
+        );
+    }
+
+    private void verifyStop() {
+        verify(mIpClient).shutdown();
+        verify(mNetworkAgent).unregister();
+    }
+
+    private void verifyNetworkAgentRegistersAndConnects() {
+        verify(mNetworkAgent).register();
+        verify(mNetworkAgent).markConnected();
+    }
+
+    private static final class TestNetworkManagementListener
+            implements INetworkInterfaceOutcomeReceiver {
+        private final CompletableFuture<String> mResult = new CompletableFuture<>();
+        private final CompletableFuture<EthernetNetworkManagementException> mError =
+                new CompletableFuture<>();
+
+        @Override
+        public void onResult(@NonNull String iface) {
+            mResult.complete(iface);
+        }
+
+        @Override
+        public void onError(@NonNull EthernetNetworkManagementException exception) {
+            mError.complete(exception);
+        }
+
+        String expectOnResult() throws Exception {
+            return mResult.get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        }
+
+        EthernetNetworkManagementException expectOnError() throws Exception {
+            return mError.get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        }
+
+        void expectOnErrorWithMessage(String msg) throws Exception {
+            assertTrue(expectOnError().getMessage().contains(msg));
+        }
+
+        @Override
+        public IBinder asBinder() {
+            return null;
+        }
+    }
+
+    @Test
+    public void testUpdateInterfaceCallsListenerCorrectlyOnSuccess() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        final NetworkCapabilities capabilities = createDefaultFilterCaps();
+        final IpConfiguration ipConfiguration = createStaticIpConfig();
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        mNetFactory.updateInterface(TEST_IFACE, ipConfiguration, capabilities, listener);
+        triggerOnProvisioningSuccess();
+
+        assertEquals(listener.expectOnResult(), TEST_IFACE);
+    }
+
+    @DevSdkIgnoreRule.IgnoreUpTo(SC_V2) // TODO: Use to Build.VERSION_CODES.SC_V2 when available
+    @Test
+    public void testUpdateInterfaceAbortsOnConcurrentRemoveInterface() throws Exception {
+        initEthernetNetworkFactory();
+        verifyNetworkManagementCallIsAbortedWhenInterrupted(
+                TEST_IFACE,
+                () -> mNetFactory.removeInterface(TEST_IFACE));
+    }
+
+    @DevSdkIgnoreRule.IgnoreUpTo(SC_V2) // TODO: Use to Build.VERSION_CODES.SC_V2 when available
+    @Test
+    public void testUpdateInterfaceAbortsOnConcurrentUpdateInterfaceLinkState() throws Exception {
+        initEthernetNetworkFactory();
+        verifyNetworkManagementCallIsAbortedWhenInterrupted(
+                TEST_IFACE,
+                () -> mNetFactory.updateInterfaceLinkState(TEST_IFACE, false, NULL_LISTENER));
+    }
+
+    @DevSdkIgnoreRule.IgnoreUpTo(SC_V2) // TODO: Use to Build.VERSION_CODES.SC_V2 when available
+    @Test
+    public void testUpdateInterfaceCallsListenerCorrectlyOnConcurrentRequests() throws Exception {
+        initEthernetNetworkFactory();
+        final NetworkCapabilities capabilities = createDefaultFilterCaps();
+        final IpConfiguration ipConfiguration = createStaticIpConfig();
+        final TestNetworkManagementListener successfulListener =
+                new TestNetworkManagementListener();
+
+        // If two calls come in before the first one completes, the first listener will be aborted
+        // and the second one will be successful.
+        verifyNetworkManagementCallIsAbortedWhenInterrupted(
+                TEST_IFACE,
+                () -> {
+                    mNetFactory.updateInterface(
+                            TEST_IFACE, ipConfiguration, capabilities, successfulListener);
+                    triggerOnProvisioningSuccess();
+                });
+
+        assertEquals(successfulListener.expectOnResult(), TEST_IFACE);
+    }
+
+    private void verifyNetworkManagementCallIsAbortedWhenInterrupted(
+            @NonNull final String iface,
+            @NonNull final Runnable interruptingRunnable) throws Exception {
+        createAndVerifyProvisionedInterface(iface);
+        final NetworkCapabilities capabilities = createDefaultFilterCaps();
+        final IpConfiguration ipConfiguration = createStaticIpConfig();
+        final TestNetworkManagementListener failedListener = new TestNetworkManagementListener();
+
+        // An active update request will be aborted on interrupt prior to provisioning completion.
+        mNetFactory.updateInterface(iface, ipConfiguration, capabilities, failedListener);
+        interruptingRunnable.run();
+
+        failedListener.expectOnErrorWithMessage("aborted");
+    }
+
+    @Test
+    public void testUpdateInterfaceRestartsAgentCorrectly() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+        final NetworkCapabilities capabilities = createDefaultFilterCaps();
+        final IpConfiguration ipConfiguration = createStaticIpConfig();
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        mNetFactory.updateInterface(TEST_IFACE, ipConfiguration, capabilities, listener);
+        triggerOnProvisioningSuccess();
+
+        assertEquals(listener.expectOnResult(), TEST_IFACE);
+        verify(mDeps).makeEthernetNetworkAgent(any(), any(),
+                eq(capabilities), any(), any(), any(), any());
+        verifyRestart(ipConfiguration);
+    }
+
+    @Test
+    public void testUpdateInterfaceForNonExistingInterface() throws Exception {
+        initEthernetNetworkFactory();
+        // No interface exists due to not calling createAndVerifyProvisionedInterface(...).
+        final NetworkCapabilities capabilities = createDefaultFilterCaps();
+        final IpConfiguration ipConfiguration = createStaticIpConfig();
+        final TestNetworkManagementListener listener = new TestNetworkManagementListener();
+
+        mNetFactory.updateInterface(TEST_IFACE, ipConfiguration, capabilities, listener);
+
+        verifyNoStopOrStart();
+        listener.expectOnErrorWithMessage("can't be updated as it is not available");
+    }
+
+    @Test
+    public void testUpdateInterfaceWithNullIpConfiguration() throws Exception {
+        initEthernetNetworkFactory();
+        createAndVerifyProvisionedInterface(TEST_IFACE);
+
+        final IpConfiguration initialIpConfig = createStaticIpConfig();
+        mNetFactory.updateInterface(TEST_IFACE, initialIpConfig, null /*capabilities*/,
+                null /*listener*/);
+        triggerOnProvisioningSuccess();
+        verifyRestart(initialIpConfig);
+
+        // TODO: have verifyXyz functions clear invocations.
+        clearInvocations(mDeps);
+        clearInvocations(mIpClient);
+        clearInvocations(mNetworkAgent);
+
+
+        // verify that sending a null ipConfig does not update the current ipConfig.
+        mNetFactory.updateInterface(TEST_IFACE, null /*ipConfig*/, null /*capabilities*/,
+                null /*listener*/);
+        triggerOnProvisioningSuccess();
+        verifyRestart(initialIpConfig);
+    }
+}
diff --git a/tests/unit/java/com/android/server/ethernet/EthernetServiceImplTest.java b/tests/unit/java/com/android/server/ethernet/EthernetServiceImplTest.java
new file mode 100644
index 0000000..dd1f1ed
--- /dev/null
+++ b/tests/unit/java/com/android/server/ethernet/EthernetServiceImplTest.java
@@ -0,0 +1,372 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import static android.net.NetworkCapabilities.TRANSPORT_TEST;
+
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.fail;
+
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.isNull;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.Manifest;
+import android.annotation.NonNull;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.EthernetNetworkUpdateRequest;
+import android.net.IpConfiguration;
+import android.net.NetworkCapabilities;
+import android.os.Handler;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class EthernetServiceImplTest {
+    private static final String TEST_IFACE = "test123";
+    private static final EthernetNetworkUpdateRequest UPDATE_REQUEST =
+            new EthernetNetworkUpdateRequest.Builder()
+                    .setIpConfiguration(new IpConfiguration())
+                    .setNetworkCapabilities(new NetworkCapabilities.Builder().build())
+                    .build();
+    private static final EthernetNetworkUpdateRequest UPDATE_REQUEST_WITHOUT_CAPABILITIES =
+            new EthernetNetworkUpdateRequest.Builder()
+                    .setIpConfiguration(new IpConfiguration())
+                    .build();
+    private static final EthernetNetworkUpdateRequest UPDATE_REQUEST_WITHOUT_IP_CONFIG =
+            new EthernetNetworkUpdateRequest.Builder()
+                    .setNetworkCapabilities(new NetworkCapabilities.Builder().build())
+                    .build();
+    private static final INetworkInterfaceOutcomeReceiver NULL_LISTENER = null;
+    private EthernetServiceImpl mEthernetServiceImpl;
+    @Mock private Context mContext;
+    @Mock private Handler mHandler;
+    @Mock private EthernetTracker mEthernetTracker;
+    @Mock private PackageManager mPackageManager;
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+        doReturn(mPackageManager).when(mContext).getPackageManager();
+        mEthernetServiceImpl = new EthernetServiceImpl(mContext, mHandler, mEthernetTracker);
+        mEthernetServiceImpl.mStarted.set(true);
+        toggleAutomotiveFeature(true);
+        shouldTrackIface(TEST_IFACE, true);
+    }
+
+    private void toggleAutomotiveFeature(final boolean isEnabled) {
+        doReturn(isEnabled)
+                .when(mPackageManager).hasSystemFeature(PackageManager.FEATURE_AUTOMOTIVE);
+    }
+
+    private void shouldTrackIface(@NonNull final String iface, final boolean shouldTrack) {
+        doReturn(shouldTrack).when(mEthernetTracker).isTrackingInterface(iface);
+    }
+
+    @Test
+    public void testSetConfigurationRejectsWhenEthNotStarted() {
+        mEthernetServiceImpl.mStarted.set(false);
+        assertThrows(IllegalStateException.class, () -> {
+            mEthernetServiceImpl.setConfiguration("" /* iface */, new IpConfiguration());
+        });
+    }
+
+    @Test
+    public void testUpdateConfigurationRejectsWhenEthNotStarted() {
+        mEthernetServiceImpl.mStarted.set(false);
+        assertThrows(IllegalStateException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(
+                    "" /* iface */, UPDATE_REQUEST, null /* listener */);
+        });
+    }
+
+    @Test
+    public void testConnectNetworkRejectsWhenEthNotStarted() {
+        mEthernetServiceImpl.mStarted.set(false);
+        assertThrows(IllegalStateException.class, () -> {
+            mEthernetServiceImpl.connectNetwork("" /* iface */, null /* listener */);
+        });
+    }
+
+    @Test
+    public void testDisconnectNetworkRejectsWhenEthNotStarted() {
+        mEthernetServiceImpl.mStarted.set(false);
+        assertThrows(IllegalStateException.class, () -> {
+            mEthernetServiceImpl.disconnectNetwork("" /* iface */, null /* listener */);
+        });
+    }
+
+    @Test
+    public void testUpdateConfigurationRejectsNullIface() {
+        assertThrows(NullPointerException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(null, UPDATE_REQUEST, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testConnectNetworkRejectsNullIface() {
+        assertThrows(NullPointerException.class, () -> {
+            mEthernetServiceImpl.connectNetwork(null /* iface */, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testDisconnectNetworkRejectsNullIface() {
+        assertThrows(NullPointerException.class, () -> {
+            mEthernetServiceImpl.disconnectNetwork(null /* iface */, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testUpdateConfigurationWithCapabilitiesRejectsWithoutAutomotiveFeature() {
+        toggleAutomotiveFeature(false);
+        assertThrows(UnsupportedOperationException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testUpdateConfigurationWithCapabilitiesWithAutomotiveFeature() {
+        toggleAutomotiveFeature(false);
+        mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST_WITHOUT_CAPABILITIES,
+                NULL_LISTENER);
+        verify(mEthernetTracker).updateConfiguration(eq(TEST_IFACE),
+                eq(UPDATE_REQUEST_WITHOUT_CAPABILITIES.getIpConfiguration()),
+                eq(UPDATE_REQUEST_WITHOUT_CAPABILITIES.getNetworkCapabilities()), isNull());
+    }
+
+    @Test
+    public void testConnectNetworkRejectsWithoutAutomotiveFeature() {
+        toggleAutomotiveFeature(false);
+        assertThrows(UnsupportedOperationException.class, () -> {
+            mEthernetServiceImpl.connectNetwork("" /* iface */, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testDisconnectNetworkRejectsWithoutAutomotiveFeature() {
+        toggleAutomotiveFeature(false);
+        assertThrows(UnsupportedOperationException.class, () -> {
+            mEthernetServiceImpl.disconnectNetwork("" /* iface */, NULL_LISTENER);
+        });
+    }
+
+    private void denyManageEthPermission() {
+        doThrow(new SecurityException("")).when(mContext)
+                .enforceCallingOrSelfPermission(
+                        eq(Manifest.permission.MANAGE_ETHERNET_NETWORKS), anyString());
+    }
+
+    private void denyManageTestNetworksPermission() {
+        doThrow(new SecurityException("")).when(mContext)
+                .enforceCallingOrSelfPermission(
+                        eq(Manifest.permission.MANAGE_TEST_NETWORKS), anyString());
+    }
+
+    @Test
+    public void testUpdateConfigurationRejectsWithoutManageEthPermission() {
+        denyManageEthPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testConnectNetworkRejectsWithoutManageEthPermission() {
+        denyManageEthPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.connectNetwork(TEST_IFACE, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testDisconnectNetworkRejectsWithoutManageEthPermission() {
+        denyManageEthPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
+        });
+    }
+
+    private void enableTestInterface() {
+        when(mEthernetTracker.isValidTestInterface(eq(TEST_IFACE))).thenReturn(true);
+    }
+
+    @Test
+    public void testUpdateConfigurationRejectsTestRequestWithoutTestPermission() {
+        enableTestInterface();
+        denyManageTestNetworksPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testConnectNetworkRejectsTestRequestWithoutTestPermission() {
+        enableTestInterface();
+        denyManageTestNetworksPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.connectNetwork(TEST_IFACE, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testDisconnectNetworkRejectsTestRequestWithoutTestPermission() {
+        enableTestInterface();
+        denyManageTestNetworksPermission();
+        assertThrows(SecurityException.class, () -> {
+            mEthernetServiceImpl.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
+        });
+    }
+
+    @Test
+    public void testUpdateConfiguration() {
+        mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST, NULL_LISTENER);
+        verify(mEthernetTracker).updateConfiguration(
+                eq(TEST_IFACE),
+                eq(UPDATE_REQUEST.getIpConfiguration()),
+                eq(UPDATE_REQUEST.getNetworkCapabilities()), eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testConnectNetwork() {
+        mEthernetServiceImpl.connectNetwork(TEST_IFACE, NULL_LISTENER);
+        verify(mEthernetTracker).connectNetwork(eq(TEST_IFACE), eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testDisconnectNetwork() {
+        mEthernetServiceImpl.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
+        verify(mEthernetTracker).disconnectNetwork(eq(TEST_IFACE), eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testUpdateConfigurationAcceptsTestRequestWithNullCapabilities() {
+        enableTestInterface();
+        final EthernetNetworkUpdateRequest request =
+                new EthernetNetworkUpdateRequest
+                        .Builder()
+                        .setIpConfiguration(new IpConfiguration()).build();
+        mEthernetServiceImpl.updateConfiguration(TEST_IFACE, request, NULL_LISTENER);
+        verify(mEthernetTracker).updateConfiguration(eq(TEST_IFACE),
+                eq(request.getIpConfiguration()),
+                eq(request.getNetworkCapabilities()), isNull());
+    }
+
+    @Test
+    public void testUpdateConfigurationAcceptsRequestWithNullIpConfiguration() {
+        mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST_WITHOUT_IP_CONFIG,
+                NULL_LISTENER);
+        verify(mEthernetTracker).updateConfiguration(eq(TEST_IFACE),
+                eq(UPDATE_REQUEST_WITHOUT_IP_CONFIG.getIpConfiguration()),
+                eq(UPDATE_REQUEST_WITHOUT_IP_CONFIG.getNetworkCapabilities()), isNull());
+    }
+
+    @Test
+    public void testUpdateConfigurationRejectsInvalidTestRequest() {
+        enableTestInterface();
+        assertThrows(IllegalArgumentException.class, () -> {
+            mEthernetServiceImpl.updateConfiguration(TEST_IFACE, UPDATE_REQUEST, NULL_LISTENER);
+        });
+    }
+
+    private EthernetNetworkUpdateRequest createTestNetworkUpdateRequest() {
+        final NetworkCapabilities nc =  new NetworkCapabilities
+                .Builder(UPDATE_REQUEST.getNetworkCapabilities())
+                .addTransportType(TRANSPORT_TEST).build();
+
+        return new EthernetNetworkUpdateRequest
+                .Builder(UPDATE_REQUEST)
+                .setNetworkCapabilities(nc).build();
+    }
+
+    @Test
+    public void testUpdateConfigurationForTestRequestDoesNotRequireAutoOrEthernetPermission() {
+        enableTestInterface();
+        toggleAutomotiveFeature(false);
+        denyManageEthPermission();
+        final EthernetNetworkUpdateRequest request = createTestNetworkUpdateRequest();
+
+        mEthernetServiceImpl.updateConfiguration(TEST_IFACE, request, NULL_LISTENER);
+        verify(mEthernetTracker).updateConfiguration(
+                eq(TEST_IFACE),
+                eq(request.getIpConfiguration()),
+                eq(request.getNetworkCapabilities()), eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testConnectNetworkForTestRequestDoesNotRequireAutoOrNetPermission() {
+        enableTestInterface();
+        toggleAutomotiveFeature(false);
+        denyManageEthPermission();
+
+        mEthernetServiceImpl.connectNetwork(TEST_IFACE, NULL_LISTENER);
+        verify(mEthernetTracker).connectNetwork(eq(TEST_IFACE), eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testDisconnectNetworkForTestRequestDoesNotRequireAutoOrNetPermission() {
+        enableTestInterface();
+        toggleAutomotiveFeature(false);
+        denyManageEthPermission();
+
+        mEthernetServiceImpl.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
+        verify(mEthernetTracker).disconnectNetwork(eq(TEST_IFACE), eq(NULL_LISTENER));
+    }
+
+    private void denyPermissions(String... permissions) {
+        for (String permission: permissions) {
+            doReturn(PackageManager.PERMISSION_DENIED).when(mContext)
+                    .checkCallingOrSelfPermission(eq(permission));
+        }
+    }
+
+    @Test
+    public void testSetEthernetEnabled() {
+        denyPermissions(android.net.NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK);
+        mEthernetServiceImpl.setEthernetEnabled(true);
+        verify(mEthernetTracker).setEthernetEnabled(true);
+        reset(mEthernetTracker);
+
+        denyPermissions(Manifest.permission.NETWORK_STACK);
+        mEthernetServiceImpl.setEthernetEnabled(false);
+        verify(mEthernetTracker).setEthernetEnabled(false);
+        reset(mEthernetTracker);
+
+        denyPermissions(Manifest.permission.NETWORK_SETTINGS);
+        try {
+            mEthernetServiceImpl.setEthernetEnabled(true);
+            fail("Should get SecurityException");
+        } catch (SecurityException e) { }
+        verify(mEthernetTracker, never()).setEthernetEnabled(false);
+    }
+}
diff --git a/tests/unit/java/com/android/server/ethernet/EthernetTrackerTest.java b/tests/unit/java/com/android/server/ethernet/EthernetTrackerTest.java
new file mode 100644
index 0000000..b1831c4
--- /dev/null
+++ b/tests/unit/java/com/android/server/ethernet/EthernetTrackerTest.java
@@ -0,0 +1,456 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.ethernet;
+
+import static android.net.TestNetworkManager.TEST_TAP_PREFIX;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.reset;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.net.EthernetManager;
+import android.net.InetAddresses;
+import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.IEthernetServiceListener;
+import android.net.INetd;
+import android.net.IpConfiguration;
+import android.net.IpConfiguration.IpAssignment;
+import android.net.IpConfiguration.ProxySettings;
+import android.net.InterfaceConfigurationParcel;
+import android.net.LinkAddress;
+import android.net.NetworkCapabilities;
+import android.net.StaticIpConfiguration;
+import android.os.HandlerThread;
+import android.os.RemoteException;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.connectivity.resources.R;
+import com.android.testutils.HandlerUtils;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+import java.net.InetAddress;
+import java.util.ArrayList;
+
+@SmallTest
+@RunWith(AndroidJUnit4.class)
+public class EthernetTrackerTest {
+    private static final String TEST_IFACE = "test123";
+    private static final int TIMEOUT_MS = 1_000;
+    private static final String THREAD_NAME = "EthernetServiceThread";
+    private static final INetworkInterfaceOutcomeReceiver NULL_LISTENER = null;
+    private EthernetTracker tracker;
+    private HandlerThread mHandlerThread;
+    @Mock private Context mContext;
+    @Mock private EthernetNetworkFactory mFactory;
+    @Mock private INetd mNetd;
+    @Mock private EthernetTracker.Dependencies mDeps;
+
+    @Before
+    public void setUp() throws RemoteException {
+        MockitoAnnotations.initMocks(this);
+        initMockResources();
+        when(mFactory.updateInterfaceLinkState(anyString(), anyBoolean(), any())).thenReturn(false);
+        when(mNetd.interfaceGetList()).thenReturn(new String[0]);
+        mHandlerThread = new HandlerThread(THREAD_NAME);
+        mHandlerThread.start();
+        tracker = new EthernetTracker(mContext, mHandlerThread.getThreadHandler(), mFactory, mNetd,
+                mDeps);
+    }
+
+    @After
+    public void cleanUp() {
+        mHandlerThread.quitSafely();
+    }
+
+    private void initMockResources() {
+        when(mDeps.getInterfaceRegexFromResource(eq(mContext))).thenReturn("");
+        when(mDeps.getInterfaceConfigFromResource(eq(mContext))).thenReturn(new String[0]);
+    }
+
+    private void waitForIdle() {
+        HandlerUtils.waitForIdle(mHandlerThread, TIMEOUT_MS);
+    }
+
+    /**
+     * Test: Creation of various valid static IP configurations
+     */
+    @Test
+    public void createStaticIpConfiguration() {
+        // Empty gives default StaticIPConfiguration object
+        assertStaticConfiguration(new StaticIpConfiguration(), "");
+
+        // Setting only the IP address properly cascades and assumes defaults
+        assertStaticConfiguration(new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress("192.0.2.10/24")).build(), "ip=192.0.2.10/24");
+
+        final ArrayList<InetAddress> dnsAddresses = new ArrayList<>();
+        dnsAddresses.add(InetAddresses.parseNumericAddress("4.4.4.4"));
+        dnsAddresses.add(InetAddresses.parseNumericAddress("8.8.8.8"));
+        // Setting other fields properly cascades them
+        assertStaticConfiguration(new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress("192.0.2.10/24"))
+                .setDnsServers(dnsAddresses)
+                .setGateway(InetAddresses.parseNumericAddress("192.0.2.1"))
+                .setDomains("android").build(),
+                "ip=192.0.2.10/24 dns=4.4.4.4,8.8.8.8 gateway=192.0.2.1 domains=android");
+
+        // Verify order doesn't matter
+        assertStaticConfiguration(new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress("192.0.2.10/24"))
+                .setDnsServers(dnsAddresses)
+                .setGateway(InetAddresses.parseNumericAddress("192.0.2.1"))
+                .setDomains("android").build(),
+                "domains=android ip=192.0.2.10/24 gateway=192.0.2.1 dns=4.4.4.4,8.8.8.8 ");
+    }
+
+    /**
+     * Test: Attempt creation of various bad static IP configurations
+     */
+    @Test
+    public void createStaticIpConfiguration_Bad() {
+        assertStaticConfigurationFails("ip=192.0.2.1/24 gateway= blah=20.20.20.20");  // Unknown key
+        assertStaticConfigurationFails("ip=192.0.2.1");  // mask is missing
+        assertStaticConfigurationFails("ip=a.b.c");  // not a valid ip address
+        assertStaticConfigurationFails("dns=4.4.4.4,1.2.3.A");  // not valid ip address in dns
+        assertStaticConfigurationFails("=");  // Key and value is empty
+        assertStaticConfigurationFails("ip=");  // Value is empty
+        assertStaticConfigurationFails("ip=192.0.2.1/24 gateway=");  // Gateway is empty
+    }
+
+    private void assertStaticConfigurationFails(String config) {
+        try {
+            EthernetTracker.parseStaticIpConfiguration(config);
+            fail("Expected to fail: " + config);
+        } catch (IllegalArgumentException e) {
+            // expected
+        }
+    }
+
+    private void assertStaticConfiguration(StaticIpConfiguration expectedStaticIpConfig,
+                String configAsString) {
+        final IpConfiguration expectedIpConfiguration = new IpConfiguration();
+        expectedIpConfiguration.setIpAssignment(IpAssignment.STATIC);
+        expectedIpConfiguration.setProxySettings(ProxySettings.NONE);
+        expectedIpConfiguration.setStaticIpConfiguration(expectedStaticIpConfig);
+
+        assertEquals(expectedIpConfiguration,
+                EthernetTracker.parseStaticIpConfiguration(configAsString));
+    }
+
+    private NetworkCapabilities.Builder makeEthernetCapabilitiesBuilder(boolean clearAll) {
+        final NetworkCapabilities.Builder builder =
+                clearAll ? NetworkCapabilities.Builder.withoutDefaultCapabilities()
+                        : new NetworkCapabilities.Builder();
+        return builder.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED)
+                .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_SUSPENDED);
+    }
+
+    /**
+     * Test: Attempt to create a capabilties with various valid sets of capabilities/transports
+     */
+    @Test
+    public void createNetworkCapabilities() {
+
+        // Particularly common expected results
+        NetworkCapabilities defaultEthernetCleared =
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                        .build();
+
+        NetworkCapabilities ethernetClearedWithCommonCaps =
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                        .addCapability(12)
+                        .addCapability(13)
+                        .addCapability(14)
+                        .addCapability(15)
+                        .build();
+
+        // Empty capabilities and transports lists with a "please clear defaults" should
+        // yield an empty capabilities set with TRANPORT_ETHERNET
+        assertParsedNetworkCapabilities(defaultEthernetCleared, true, "", "");
+
+        // Empty capabilities and transports without the clear defaults flag should return the
+        // default capabilities set with TRANSPORT_ETHERNET
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(false /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                        .build(),
+                false, "", "");
+
+        // A list of capabilities without the clear defaults flag should return the default
+        // capabilities, mixed with the desired capabilities, and TRANSPORT_ETHERNET
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(false /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET)
+                        .addCapability(11)
+                        .addCapability(12)
+                        .build(),
+                false, "11,12", "");
+
+        // Adding a list of capabilities with a clear defaults will leave exactly those capabilities
+        // with a default TRANSPORT_ETHERNET since no overrides are specified
+        assertParsedNetworkCapabilities(ethernetClearedWithCommonCaps, true, "12,13,14,15", "");
+
+        // Adding any invalid capabilities to the list will cause them to be ignored
+        assertParsedNetworkCapabilities(ethernetClearedWithCommonCaps, true, "12,13,14,15,65,73", "");
+        assertParsedNetworkCapabilities(ethernetClearedWithCommonCaps, true, "12,13,14,15,abcdefg", "");
+
+        // Adding a valid override transport will remove the default TRANSPORT_ETHERNET transport
+        // and apply only the override to the capabiltities object
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(0)
+                        .build(),
+                true, "", "0");
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(1)
+                        .build(),
+                true, "", "1");
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(2)
+                        .build(),
+                true, "", "2");
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addTransportType(3)
+                        .build(),
+                true, "", "3");
+
+        // "4" is TRANSPORT_VPN, which is unsupported. Should default back to TRANPORT_ETHERNET
+        assertParsedNetworkCapabilities(defaultEthernetCleared, true, "", "4");
+
+        // "5" is TRANSPORT_WIFI_AWARE, which is currently supported due to no legacy TYPE_NONE
+        // conversion. When that becomes available, this test must be updated
+        assertParsedNetworkCapabilities(defaultEthernetCleared, true, "", "5");
+
+        // "6" is TRANSPORT_LOWPAN, which is currently supported due to no legacy TYPE_NONE
+        // conversion. When that becomes available, this test must be updated
+        assertParsedNetworkCapabilities(defaultEthernetCleared, true, "", "6");
+
+        // Adding an invalid override transport will leave the transport as TRANSPORT_ETHERNET
+        assertParsedNetworkCapabilities(defaultEthernetCleared,true, "", "100");
+        assertParsedNetworkCapabilities(defaultEthernetCleared, true, "", "abcdefg");
+
+        // Ensure the adding of both capabilities and transports work
+        assertParsedNetworkCapabilities(
+                makeEthernetCapabilitiesBuilder(true /* clearAll */)
+                        .setLinkUpstreamBandwidthKbps(100000)
+                        .setLinkDownstreamBandwidthKbps(100000)
+                        .addCapability(12)
+                        .addCapability(13)
+                        .addCapability(14)
+                        .addCapability(15)
+                        .addTransportType(3)
+                        .build(),
+                true, "12,13,14,15", "3");
+
+        // Ensure order does not matter for capability list
+        assertParsedNetworkCapabilities(ethernetClearedWithCommonCaps, true, "13,12,15,14", "");
+    }
+
+    private void assertParsedNetworkCapabilities(NetworkCapabilities expectedNetworkCapabilities,
+            boolean clearCapabilties, String configCapabiltiies,String configTransports) {
+        assertEquals(expectedNetworkCapabilities,
+                EthernetTracker.createNetworkCapabilities(clearCapabilties, configCapabiltiies,
+                        configTransports).build());
+    }
+
+    @Test
+    public void testCreateEthernetTrackerConfigReturnsCorrectValue() {
+        final String capabilities = "2";
+        final String ipConfig = "3";
+        final String transport = "4";
+        final String configString = String.join(";", TEST_IFACE, capabilities, ipConfig, transport);
+
+        final EthernetTracker.EthernetTrackerConfig config =
+                EthernetTracker.createEthernetTrackerConfig(configString);
+
+        assertEquals(TEST_IFACE, config.mIface);
+        assertEquals(capabilities, config.mCapabilities);
+        assertEquals(ipConfig, config.mIpConfig);
+        assertEquals(transport, config.mTransport);
+    }
+
+    @Test
+    public void testCreateEthernetTrackerConfigThrowsNpeWithNullInput() {
+        assertThrows(NullPointerException.class,
+                () -> EthernetTracker.createEthernetTrackerConfig(null));
+    }
+
+    @Test
+    public void testUpdateConfiguration() {
+        final NetworkCapabilities capabilities = new NetworkCapabilities.Builder().build();
+        final LinkAddress linkAddr = new LinkAddress("192.0.2.2/25");
+        final StaticIpConfiguration staticIpConfig =
+                new StaticIpConfiguration.Builder().setIpAddress(linkAddr).build();
+        final IpConfiguration ipConfig =
+                new IpConfiguration.Builder().setStaticIpConfiguration(staticIpConfig).build();
+        final INetworkInterfaceOutcomeReceiver listener = null;
+
+        tracker.updateConfiguration(TEST_IFACE, ipConfig, capabilities, listener);
+        waitForIdle();
+
+        verify(mFactory).updateInterface(
+                eq(TEST_IFACE), eq(ipConfig), eq(capabilities), eq(listener));
+    }
+
+    @Test
+    public void testConnectNetworkCorrectlyCallsFactory() {
+        tracker.connectNetwork(TEST_IFACE, NULL_LISTENER);
+        waitForIdle();
+
+        verify(mFactory).updateInterfaceLinkState(eq(TEST_IFACE), eq(true /* up */),
+                eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testDisconnectNetworkCorrectlyCallsFactory() {
+        tracker.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
+        waitForIdle();
+
+        verify(mFactory).updateInterfaceLinkState(eq(TEST_IFACE), eq(false /* up */),
+                eq(NULL_LISTENER));
+    }
+
+    @Test
+    public void testIsValidTestInterfaceIsFalseWhenTestInterfacesAreNotIncluded() {
+        final String validIfaceName = TEST_TAP_PREFIX + "123";
+        tracker.setIncludeTestInterfaces(false);
+        waitForIdle();
+
+        final boolean isValidTestInterface = tracker.isValidTestInterface(validIfaceName);
+
+        assertFalse(isValidTestInterface);
+    }
+
+    @Test
+    public void testIsValidTestInterfaceIsFalseWhenTestInterfaceNameIsInvalid() {
+        final String invalidIfaceName = "123" + TEST_TAP_PREFIX;
+        tracker.setIncludeTestInterfaces(true);
+        waitForIdle();
+
+        final boolean isValidTestInterface = tracker.isValidTestInterface(invalidIfaceName);
+
+        assertFalse(isValidTestInterface);
+    }
+
+    @Test
+    public void testIsValidTestInterfaceIsTrueWhenTestInterfacesIncludedAndValidName() {
+        final String validIfaceName = TEST_TAP_PREFIX + "123";
+        tracker.setIncludeTestInterfaces(true);
+        waitForIdle();
+
+        final boolean isValidTestInterface = tracker.isValidTestInterface(validIfaceName);
+
+        assertTrue(isValidTestInterface);
+    }
+
+    public static class EthernetStateListener extends IEthernetServiceListener.Stub {
+        @Override
+        public void onEthernetStateChanged(int state) { }
+
+        @Override
+        public void onInterfaceStateChanged(String iface, int state, int role,
+                IpConfiguration configuration) { }
+    }
+
+    @Test
+    public void testListenEthernetStateChange() throws Exception {
+        final String testIface = "testtap123";
+        final String testHwAddr = "11:22:33:44:55:66";
+        final InterfaceConfigurationParcel ifaceParcel = new InterfaceConfigurationParcel();
+        ifaceParcel.ifName = testIface;
+        ifaceParcel.hwAddr = testHwAddr;
+        ifaceParcel.flags = new String[] {INetd.IF_STATE_UP};
+
+        tracker.setIncludeTestInterfaces(true);
+        waitForIdle();
+
+        when(mNetd.interfaceGetList()).thenReturn(new String[] {testIface});
+        when(mNetd.interfaceGetCfg(eq(testIface))).thenReturn(ifaceParcel);
+        doReturn(new String[] {testIface}).when(mFactory).getAvailableInterfaces(anyBoolean());
+        doReturn(EthernetManager.STATE_LINK_UP).when(mFactory).getInterfaceState(eq(testIface));
+
+        final EthernetStateListener listener = spy(new EthernetStateListener());
+        tracker.addListener(listener, true /* canUseRestrictedNetworks */);
+        // Check default state.
+        waitForIdle();
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_LINK_UP),
+                anyInt(), any());
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_ENABLED));
+        reset(listener);
+
+        doReturn(EthernetManager.STATE_ABSENT).when(mFactory).getInterfaceState(eq(testIface));
+        tracker.setEthernetEnabled(false);
+        waitForIdle();
+        verify(mFactory).removeInterface(eq(testIface));
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_DISABLED));
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_ABSENT),
+                anyInt(), any());
+        reset(listener);
+
+        doReturn(EthernetManager.STATE_LINK_UP).when(mFactory).getInterfaceState(eq(testIface));
+        tracker.setEthernetEnabled(true);
+        waitForIdle();
+        verify(mFactory).addInterface(eq(testIface), eq(testHwAddr), any(), any());
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_ENABLED));
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_LINK_UP),
+                anyInt(), any());
+    }
+}
diff --git a/tests/unit/java/com/android/server/net/IpConfigStoreTest.java b/tests/unit/java/com/android/server/net/IpConfigStoreTest.java
new file mode 100644
index 0000000..e9a5309
--- /dev/null
+++ b/tests/unit/java/com/android/server/net/IpConfigStoreTest.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.net;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.fail;
+
+import android.net.InetAddresses;
+import android.net.IpConfiguration;
+import android.net.IpConfiguration.IpAssignment;
+import android.net.IpConfiguration.ProxySettings;
+import android.net.LinkAddress;
+import android.net.ProxyInfo;
+import android.net.StaticIpConfiguration;
+import android.util.ArrayMap;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.Arrays;
+
+/**
+ * Unit tests for {@link IpConfigStore}
+ */
+@RunWith(AndroidJUnit4.class)
+public class IpConfigStoreTest {
+    private static final int KEY_CONFIG = 17;
+    private static final String IFACE_1 = "eth0";
+    private static final String IFACE_2 = "eth1";
+    private static final String IP_ADDR_1 = "192.168.1.10/24";
+    private static final String IP_ADDR_2 = "192.168.1.20/24";
+    private static final String DNS_IP_ADDR_1 = "1.2.3.4";
+    private static final String DNS_IP_ADDR_2 = "5.6.7.8";
+
+    @Test
+    public void backwardCompatibility2to3() throws IOException {
+        ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
+        DataOutputStream outputStream = new DataOutputStream(byteStream);
+
+        final IpConfiguration expectedConfig =
+                newIpConfiguration(IpAssignment.DHCP, ProxySettings.NONE, null, null);
+
+        // Emulate writing to old format.
+        writeDhcpConfigV2(outputStream, KEY_CONFIG, expectedConfig);
+
+        InputStream in = new ByteArrayInputStream(byteStream.toByteArray());
+        ArrayMap<String, IpConfiguration> configurations = IpConfigStore.readIpConfigurations(in);
+
+        assertNotNull(configurations);
+        assertEquals(1, configurations.size());
+        IpConfiguration actualConfig = configurations.get(String.valueOf(KEY_CONFIG));
+        assertNotNull(actualConfig);
+        assertEquals(expectedConfig, actualConfig);
+    }
+
+    @Test
+    public void staticIpMultiNetworks() throws Exception {
+        final ArrayList<InetAddress> dnsServers = new ArrayList<>();
+        dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_1));
+        dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_2));
+        final StaticIpConfiguration staticIpConfiguration1 = new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress(IP_ADDR_1))
+                .setDnsServers(dnsServers).build();
+        final StaticIpConfiguration staticIpConfiguration2 = new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress(IP_ADDR_2))
+                .setDnsServers(dnsServers).build();
+
+        ProxyInfo proxyInfo =
+                ProxyInfo.buildDirectProxy("10.10.10.10", 88, Arrays.asList("host1", "host2"));
+
+        IpConfiguration expectedConfig1 = newIpConfiguration(IpAssignment.STATIC,
+                ProxySettings.STATIC, staticIpConfiguration1, proxyInfo);
+        IpConfiguration expectedConfig2 = newIpConfiguration(IpAssignment.STATIC,
+                ProxySettings.STATIC, staticIpConfiguration2, proxyInfo);
+
+        ArrayMap<String, IpConfiguration> expectedNetworks = new ArrayMap<>();
+        expectedNetworks.put(IFACE_1, expectedConfig1);
+        expectedNetworks.put(IFACE_2, expectedConfig2);
+
+        MockedDelayedDiskWrite writer = new MockedDelayedDiskWrite();
+        IpConfigStore store = new IpConfigStore(writer);
+        store.writeIpConfigurations("file/path/not/used/", expectedNetworks);
+
+        InputStream in = new ByteArrayInputStream(writer.mByteStream.toByteArray());
+        ArrayMap<String, IpConfiguration> actualNetworks = IpConfigStore.readIpConfigurations(in);
+        assertNotNull(actualNetworks);
+        assertEquals(2, actualNetworks.size());
+        assertEquals(expectedNetworks.get(IFACE_1), actualNetworks.get(IFACE_1));
+        assertEquals(expectedNetworks.get(IFACE_2), actualNetworks.get(IFACE_2));
+    }
+
+    private IpConfiguration newIpConfiguration(IpAssignment ipAssignment,
+            ProxySettings proxySettings, StaticIpConfiguration staticIpConfig, ProxyInfo info) {
+        final IpConfiguration config = new IpConfiguration();
+        config.setIpAssignment(ipAssignment);
+        config.setProxySettings(proxySettings);
+        config.setStaticIpConfiguration(staticIpConfig);
+        config.setHttpProxy(info);
+        return config;
+    }
+
+    // This is simplified snapshot of code that was used to store values in V2 format (key as int).
+    private static void writeDhcpConfigV2(DataOutputStream out, int configKey,
+            IpConfiguration config) throws IOException {
+        out.writeInt(2);  // VERSION 2
+        switch (config.getIpAssignment()) {
+            case DHCP:
+                out.writeUTF("ipAssignment");
+                out.writeUTF(config.getIpAssignment().toString());
+                break;
+            default:
+                fail("Not supported in test environment");
+        }
+
+        out.writeUTF("id");
+        out.writeInt(configKey);
+        out.writeUTF("eos");
+    }
+
+    /** Synchronously writes into given byte steam */
+    private static class MockedDelayedDiskWrite extends DelayedDiskWrite {
+        final ByteArrayOutputStream mByteStream = new ByteArrayOutputStream();
+
+        @Override
+        public void write(String filePath, Writer w) {
+            DataOutputStream outputStream = new DataOutputStream(mByteStream);
+
+            try {
+                w.onWriteCalled(outputStream);
+            } catch (IOException e) {
+                fail();
+            }
+        }
+    }
+}