Merge "only register jni for ClatCoordinator on T+"
diff --git a/bpf_progs/block.c b/bpf_progs/block.c
index f2a3e62..3797a38 100644
--- a/bpf_progs/block.c
+++ b/bpf_progs/block.c
@@ -19,8 +19,8 @@
 #include <netinet/in.h>
 #include <stdint.h>
 
-// The resulting .o needs to load on the Android T beta 3 bpfloader
-#define BPFLOADER_MIN_VER BPFLOADER_T_BETA3_VERSION
+// The resulting .o needs to load on the Android T bpfloader
+#define BPFLOADER_MIN_VER BPFLOADER_T_VERSION
 
 #include "bpf_helpers.h"
 
diff --git a/bpf_progs/clatd.c b/bpf_progs/clatd.c
index f05b93e..85ba58e 100644
--- a/bpf_progs/clatd.c
+++ b/bpf_progs/clatd.c
@@ -30,8 +30,8 @@
 #define __kernel_udphdr udphdr
 #include <linux/udp.h>
 
-// The resulting .o needs to load on the Android T beta 3 bpfloader
-#define BPFLOADER_MIN_VER BPFLOADER_T_BETA3_VERSION
+// The resulting .o needs to load on the Android T bpfloader
+#define BPFLOADER_MIN_VER BPFLOADER_T_VERSION
 
 #include "bpf_helpers.h"
 #include "bpf_net_helpers.h"
diff --git a/bpf_progs/dscpPolicy.c b/bpf_progs/dscpPolicy.c
index 72f63c6..262b65b 100644
--- a/bpf_progs/dscpPolicy.c
+++ b/bpf_progs/dscpPolicy.c
@@ -27,8 +27,8 @@
 #include <stdint.h>
 #include <string.h>
 
-// The resulting .o needs to load on the Android T beta 3 bpfloader
-#define BPFLOADER_MIN_VER BPFLOADER_T_BETA3_VERSION
+// The resulting .o needs to load on the Android T bpfloader
+#define BPFLOADER_MIN_VER BPFLOADER_T_VERSION
 
 #include "bpf_helpers.h"
 #include "dscpPolicy.h"
diff --git a/bpf_progs/netd.c b/bpf_progs/netd.c
index 39dff7f..839ca40 100644
--- a/bpf_progs/netd.c
+++ b/bpf_progs/netd.c
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-// The resulting .o needs to load on the Android T Beta 3 bpfloader
-#define BPFLOADER_MIN_VER BPFLOADER_T_BETA3_VERSION
+// The resulting .o needs to load on the Android T bpfloader
+#define BPFLOADER_MIN_VER BPFLOADER_T_VERSION
 
 #include <bpf_helpers.h>
 #include <linux/bpf.h>
diff --git a/nearby/tests/multidevices/README.md b/nearby/tests/multidevices/README.md
index b64667c..9d086de 100644
--- a/nearby/tests/multidevices/README.md
+++ b/nearby/tests/multidevices/README.md
@@ -43,14 +43,24 @@
 *   Adjust Bluetooth profile configurations. \
     The Fast Pair provider simulator is an opposite role to the seeker. It needs
     to enable/disable the following Bluetooth profile:
-    *   Disable A2DP (profile_supported_a2dp)
-    *   Disable the AVRCP controller (profile_supported_avrcp_controller)
-    *   Enable A2DP sink (profile_supported_a2dp_sink)
-    *   Enable the HFP client connection service (profile_supported_hfpclient,
-        hfp_client_connection_service_enabled)
-    *   Enable the AVRCP target (profile_supported_avrcp_target)
-    *   Enable the automatic audio focus request
-        (a2dp_sink_automatically_request_audio_focus)
+    *   Disable A2DP source (bluetooth.profile.a2dp.source.enabled)
+    *   Enable A2DP sink (bluetooth.profile.a2dp.sink.enabled)
+    *   Disable the AVRCP controller (bluetooth.profile.avrcp.controller.enabled)
+    *   Enable the AVRCP target (bluetooth.profile.avrcp.target.enabled)
+    *   Enable the HFP service (bluetooth.profile.hfp.ag.enabled, bluetooth.profile.hfp.hf.enabled)
+
+```makefile
+# The Bluetooth profiles that Fast Pair provider simulator expect to have enabled.
+PRODUCT_PRODUCT_PROPERTIES += \
+    bluetooth.device.default_name=FastPairProviderSimulator \
+    bluetooth.profile.a2dp.source.enabled=false \
+    bluetooth.profile.a2dp.sink.enabled=true \
+    bluetooth.profile.avrcp.controller.enabled=false \
+    bluetooth.profile.avrcp.target.enabled=true \
+    bluetooth.profile.hfp.ag.enabled=true \
+    bluetooth.profile.hfp.hf.enabled=true
+```
+
 *   Adjust Bluetooth TX power limitation in Bluetooth module and disable the
     Fast Pair in Google Play service (aka GMS)
 
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceCache.java b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceCache.java
new file mode 100644
index 0000000..bfda535
--- /dev/null
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceCache.java
@@ -0,0 +1,178 @@
+/*
+ * Copyright (C) 2023 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.connectivity.mdns;
+
+import static com.android.server.connectivity.mdns.MdnsSocketProvider.ensureRunningOnHandlerThread;
+import static com.android.server.connectivity.mdns.util.MdnsUtils.equalsIgnoreDnsCase;
+import static com.android.server.connectivity.mdns.util.MdnsUtils.toDnsLowerCase;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.net.Network;
+import android.os.Handler;
+import android.os.Looper;
+import android.util.ArrayMap;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * The {@link MdnsServiceCache} manages the service which discovers from each socket and cache these
+ * services to reduce duplicated queries.
+ *
+ * <p>This class is not thread safe, it is intended to be used only from the looper thread.
+ *  However, the constructor is an exception, as it is called on another thread;
+ *  therefore for thread safety all members of this class MUST either be final or initialized
+ *  to their default value (0, false or null).
+ */
+public class MdnsServiceCache {
+    private static class CacheKey {
+        @NonNull final String mLowercaseServiceType;
+        @Nullable final Network mNetwork;
+
+        CacheKey(@NonNull String serviceType, @Nullable Network network) {
+            mLowercaseServiceType = toDnsLowerCase(serviceType);
+            mNetwork = network;
+        }
+
+        @Override public int hashCode() {
+            return Objects.hash(mLowercaseServiceType, mNetwork);
+        }
+
+        @Override public boolean equals(Object other) {
+            if (this == other) {
+                return true;
+            }
+            if (!(other instanceof CacheKey)) {
+                return false;
+            }
+            return Objects.equals(mLowercaseServiceType, ((CacheKey) other).mLowercaseServiceType)
+                    && Objects.equals(mNetwork, ((CacheKey) other).mNetwork);
+        }
+    }
+    /**
+     * A map of cached services. Key is composed of service name, type and network. Value is the
+     * service which use the service type to discover from each socket.
+     */
+    @NonNull
+    private final ArrayMap<CacheKey, List<MdnsResponse>> mCachedServices = new ArrayMap<>();
+    @NonNull
+    private final Handler mHandler;
+
+    public MdnsServiceCache(@NonNull Looper looper) {
+        mHandler = new Handler(looper);
+    }
+
+    /**
+     * Get the cache services which are queried from given service type and network.
+     *
+     * @param serviceType the target service type.
+     * @param network the target network
+     * @return the set of services which matches the given service type.
+     */
+    @NonNull
+    public List<MdnsResponse> getCachedServices(@NonNull String serviceType,
+            @Nullable Network network) {
+        ensureRunningOnHandlerThread(mHandler);
+        final CacheKey key = new CacheKey(serviceType, network);
+        return mCachedServices.containsKey(key)
+                ? Collections.unmodifiableList(new ArrayList<>(mCachedServices.get(key)))
+                : Collections.emptyList();
+    }
+
+    private MdnsResponse findMatchedResponse(@NonNull List<MdnsResponse> responses,
+            @NonNull String serviceName) {
+        for (MdnsResponse response : responses) {
+            if (equalsIgnoreDnsCase(serviceName, response.getServiceInstanceName())) {
+                return response;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Get the cache service.
+     *
+     * @param serviceName the target service name.
+     * @param serviceType the target service type.
+     * @param network the target network
+     * @return the service which matches given conditions.
+     */
+    @Nullable
+    public MdnsResponse getCachedService(@NonNull String serviceName,
+            @NonNull String serviceType, @Nullable Network network) {
+        ensureRunningOnHandlerThread(mHandler);
+        final List<MdnsResponse> responses =
+                mCachedServices.get(new CacheKey(serviceType, network));
+        if (responses == null) {
+            return null;
+        }
+        final MdnsResponse response = findMatchedResponse(responses, serviceName);
+        return response != null ? new MdnsResponse(response) : null;
+    }
+
+    /**
+     * Add or update a service.
+     *
+     * @param serviceType the service type.
+     * @param network the target network
+     * @param response the response of the discovered service.
+     */
+    public void addOrUpdateService(@NonNull String serviceType, @Nullable Network network,
+            @NonNull MdnsResponse response) {
+        ensureRunningOnHandlerThread(mHandler);
+        final List<MdnsResponse> responses = mCachedServices.computeIfAbsent(
+                new CacheKey(serviceType, network), key -> new ArrayList<>());
+        // Remove existing service if present.
+        final MdnsResponse existing =
+                findMatchedResponse(responses, response.getServiceInstanceName());
+        responses.remove(existing);
+        responses.add(response);
+    }
+
+    /**
+     * Remove a service which matches the given service name, type and network.
+     *
+     * @param serviceName the target service name.
+     * @param serviceType the target service type.
+     * @param network the target network.
+     */
+    @Nullable
+    public MdnsResponse removeService(@NonNull String serviceName, @NonNull String serviceType,
+            @Nullable Network network) {
+        ensureRunningOnHandlerThread(mHandler);
+        final List<MdnsResponse> responses =
+                mCachedServices.get(new CacheKey(serviceType, network));
+        if (responses == null) {
+            return null;
+        }
+        final Iterator<MdnsResponse> iterator = responses.iterator();
+        while (iterator.hasNext()) {
+            final MdnsResponse response = iterator.next();
+            if (equalsIgnoreDnsCase(serviceName, response.getServiceInstanceName())) {
+                iterator.remove();
+                return response;
+            }
+        }
+        return null;
+    }
+
+    // TODO: check ttl expiration for each service and notify to the clients.
+}
diff --git a/service-t/src/com/android/server/connectivity/mdns/util/MdnsUtils.java b/service-t/src/com/android/server/connectivity/mdns/util/MdnsUtils.java
new file mode 100644
index 0000000..4b0f2a4
--- /dev/null
+++ b/service-t/src/com/android/server/connectivity/mdns/util/MdnsUtils.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2023 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.connectivity.mdns.util;
+
+import android.annotation.NonNull;
+
+/**
+ * Mdns utility functions.
+ */
+public class MdnsUtils {
+
+    private MdnsUtils() { }
+
+    /**
+     * Convert the string to DNS case-insensitive lowercase
+     *
+     * Per rfc6762#page-46, accented characters are not defined to be automatically equivalent to
+     * their unaccented counterparts. So the "DNS lowercase" should be if character is A-Z then they
+     * transform into a-z. Otherwise, they are kept as-is.
+     */
+    public static String toDnsLowerCase(@NonNull String string) {
+        final char[] outChars = new char[string.length()];
+        for (int i = 0; i < string.length(); i++) {
+            outChars[i] = toDnsLowerCase(string.charAt(i));
+        }
+        return new String(outChars);
+    }
+
+    /**
+     * Compare two strings by DNS case-insensitive lowercase.
+     */
+    public static boolean equalsIgnoreDnsCase(@NonNull String a, @NonNull String b) {
+        if (a.length() != b.length()) return false;
+        for (int i = 0; i < a.length(); i++) {
+            if (toDnsLowerCase(a.charAt(i)) != toDnsLowerCase(b.charAt(i))) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static char toDnsLowerCase(char a) {
+        return a >= 'A' && a <= 'Z' ? (char) (a + ('a' - 'A')) : a;
+    }
+}
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index 961337d..c660792 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -946,7 +946,11 @@
     @GuardedBy("mStatsLock")
     private void shutdownLocked() {
         final TetheringManager tetheringManager = mContext.getSystemService(TetheringManager.class);
-        tetheringManager.unregisterTetheringEventCallback(mTetherListener);
+        try {
+            tetheringManager.unregisterTetheringEventCallback(mTetherListener);
+        } catch (IllegalStateException e) {
+            Log.i(TAG, "shutdownLocked: error when unregister tethering, ignored. e=" + e);
+        }
         mContext.unregisterReceiver(mPollReceiver);
         mContext.unregisterReceiver(mRemovedReceiver);
         mContext.unregisterReceiver(mUserReceiver);
diff --git a/service/jni/com_android_server_connectivity_ClatCoordinator.cpp b/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
index 059b716..8d909ed 100644
--- a/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
+++ b/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
@@ -485,11 +485,15 @@
 static constexpr int WAITPID_ATTEMPTS = 50;
 static constexpr int WAITPID_RETRY_INTERVAL_US = 100000;
 
-static void stopClatdProcess(int pid) {
-    int err = kill(pid, SIGTERM);
-    if (err) {
-        err = errno;
+static void com_android_server_connectivity_ClatCoordinator_stopClatd(JNIEnv* env, jclass clazz,
+                                                                      jint pid) {
+    if (pid <= 0) {
+        jniThrowExceptionFmt(env, "java/io/IOException", "Invalid pid");
+        return;
     }
+
+    int err = kill(pid, SIGTERM);
+    if (err) err = errno;
     if (err == ESRCH) {
         ALOGE("clatd child process %d unexpectedly disappeared", pid);
         return;
@@ -518,23 +522,6 @@
     }
 }
 
-static void com_android_server_connectivity_ClatCoordinator_stopClatd(JNIEnv* env, jclass clazz,
-                                                                      jstring iface, jstring pfx96,
-                                                                      jstring v4, jstring v6,
-                                                                      jint pid) {
-    ScopedUtfChars ifaceStr(env, iface);
-    ScopedUtfChars pfx96Str(env, pfx96);
-    ScopedUtfChars v4Str(env, v4);
-    ScopedUtfChars v6Str(env, v6);
-
-    if (pid <= 0) {
-        jniThrowExceptionFmt(env, "java/io/IOException", "Invalid pid");
-        return;
-    }
-
-    stopClatdProcess(pid);
-}
-
 static jlong com_android_server_connectivity_ClatCoordinator_getSocketCookie(
         JNIEnv* env, jclass clazz, jobject sockJavaFd) {
     int sockFd = netjniutils::GetNativeFileDescriptor(env, sockJavaFd);
@@ -579,8 +566,7 @@
          "(Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;Ljava/lang/"
          "String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)I",
          (void*)com_android_server_connectivity_ClatCoordinator_startClatd},
-        {"native_stopClatd",
-         "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;I)V",
+        {"native_stopClatd", "(I)V",
          (void*)com_android_server_connectivity_ClatCoordinator_stopClatd},
         {"native_getSocketCookie", "(Ljava/io/FileDescriptor;)J",
          (void*)com_android_server_connectivity_ClatCoordinator_getSocketCookie},
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index ba503e0..b449e72 100755
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -244,6 +244,7 @@
 import android.util.LocalLog;
 import android.util.Log;
 import android.util.Pair;
+import android.util.Range;
 import android.util.SparseArray;
 import android.util.SparseIntArray;
 
@@ -310,11 +311,13 @@
 
 import java.io.FileDescriptor;
 import java.io.IOException;
+import java.io.InterruptedIOException;
 import java.io.PrintWriter;
 import java.io.Writer;
 import java.net.Inet4Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
+import java.net.SocketException;
 import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -1485,6 +1488,18 @@
                 @NonNull final UserHandle user) {
             return CompatChanges.isChangeEnabled(changeId, packageName, user);
         }
+
+        /**
+         * Call {@link InetDiagMessage#destroyLiveTcpSockets(Set, Set)}
+         *
+         * @param ranges target uid ranges
+         * @param exemptUids uids to skip close socket
+         */
+        public void destroyLiveTcpSockets(@NonNull final Set<Range<Integer>> ranges,
+                @NonNull final Set<Integer> exemptUids)
+                throws SocketException, InterruptedIOException, ErrnoException {
+            InetDiagMessage.destroyLiveTcpSockets(ranges, exemptUids);
+        }
     }
 
     public ConnectivityService(Context context) {
@@ -7910,10 +7925,20 @@
         return SdkLevel.isAtLeastU() ? (networkHandle + ":" + iface) : ("iface:" + iface);
     }
 
+    private static boolean isWakeupMarkingSupported(NetworkCapabilities capabilities) {
+        if (capabilities.hasTransport(TRANSPORT_WIFI)) {
+            return true;
+        }
+        if (SdkLevel.isAtLeastU() && capabilities.hasTransport(TRANSPORT_CELLULAR)) {
+            return true;
+        }
+        return false;
+    }
+
     private void wakeupModifyInterface(String iface, NetworkAgentInfo nai, boolean add) {
         // Marks are only available on WiFi interfaces. Checking for
         // marks on unsupported interfaces is harmless.
-        if (!nai.networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
+        if (!isWakeupMarkingSupported(nai.networkCapabilities)) {
             return;
         }
 
@@ -8448,11 +8473,11 @@
         return stableRanges;
     }
 
-    private void maybeCloseSockets(NetworkAgentInfo nai, UidRangeParcel[] ranges,
-            int[] exemptUids) {
+    private void maybeCloseSockets(NetworkAgentInfo nai, Set<UidRange> ranges,
+            Set<Integer> exemptUids) {
         if (nai.isVPN() && !nai.networkAgentConfig.allowBypass) {
             try {
-                mNetd.socketDestroy(ranges, exemptUids);
+                mDeps.destroyLiveTcpSockets(UidRange.toIntRanges(ranges), exemptUids);
             } catch (Exception e) {
                 loge("Exception in socket destroy: ", e);
             }
@@ -8460,16 +8485,16 @@
     }
 
     private void updateVpnUidRanges(boolean add, NetworkAgentInfo nai, Set<UidRange> uidRanges) {
-        int[] exemptUids = new int[2];
+        final Set<Integer> exemptUids = new ArraySet<>();
         // TODO: Excluding VPN_UID is necessary in order to not to kill the TCP connection used
         // by PPTP. Fix this by making Vpn set the owner UID to VPN_UID instead of system when
         // starting a legacy VPN, and remove VPN_UID here. (b/176542831)
-        exemptUids[0] = VPN_UID;
-        exemptUids[1] = nai.networkCapabilities.getOwnerUid();
+        exemptUids.add(VPN_UID);
+        exemptUids.add(nai.networkCapabilities.getOwnerUid());
         UidRangeParcel[] ranges = toUidRangeStableParcels(uidRanges);
 
         // Close sockets before modifying uid ranges so that RST packets can reach to the server.
-        maybeCloseSockets(nai, ranges, exemptUids);
+        maybeCloseSockets(nai, uidRanges, exemptUids);
         try {
             if (add) {
                 mNetd.networkAddUidRangesParcel(new NativeUidRangeConfig(
@@ -8483,7 +8508,7 @@
                     " on netId " + nai.network.netId + ". " + e);
         }
         // Close sockets that established connection while requesting netd.
-        maybeCloseSockets(nai, ranges, exemptUids);
+        maybeCloseSockets(nai, uidRanges, exemptUids);
     }
 
     private boolean isProxySetOnAnyDefaultNetwork() {
diff --git a/service/src/com/android/server/connectivity/ClatCoordinator.java b/service/src/com/android/server/connectivity/ClatCoordinator.java
index 5d04632..fbe706c 100644
--- a/service/src/com/android/server/connectivity/ClatCoordinator.java
+++ b/service/src/com/android/server/connectivity/ClatCoordinator.java
@@ -237,9 +237,8 @@
         /**
          * Stop clatd.
          */
-        public void stopClatd(String iface, String pfx96, String v4, String v6, int pid)
-                throws IOException {
-            native_stopClatd(iface, pfx96, v4, v6, pid);
+        public void stopClatd(int pid) throws IOException {
+            native_stopClatd(pid);
         }
 
         /**
@@ -843,9 +842,7 @@
         Log.i(TAG, "Stopping clatd pid=" + mClatdTracker.pid + " on " + mClatdTracker.iface);
 
         maybeStopBpf(mClatdTracker);
-        mDeps.stopClatd(mClatdTracker.iface, mClatdTracker.pfx96.getHostAddress(),
-                mClatdTracker.v4.getHostAddress(), mClatdTracker.v6.getHostAddress(),
-                mClatdTracker.pid);
+        mDeps.stopClatd(mClatdTracker.pid);
         untagSocket(mClatdTracker.cookie);
 
         Log.i(TAG, "clatd on " + mClatdTracker.iface + " stopped");
@@ -944,7 +941,6 @@
     private static native int native_startClatd(FileDescriptor tunfd, FileDescriptor readsock6,
             FileDescriptor writesock6, String iface, String pfx96, String v4, String v6)
             throws IOException;
-    private static native void native_stopClatd(String iface, String pfx96, String v4, String v6,
-            int pid) throws IOException;
+    private static native void native_stopClatd(int pid) throws IOException;
     private static native long native_getSocketCookie(FileDescriptor sock) throws IOException;
 }
diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
index c28ee64..624acd3 100755
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
@@ -154,7 +154,6 @@
 import java.util.Random;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
 
@@ -809,26 +808,12 @@
                 mOldPrivateDnsSpecifier);
     }
 
-    // TODO: replace with CtsNetUtils.awaitPrivateDnsSetting in Q or above.
     private void expectPrivateDnsHostname(final String hostname) throws Exception {
-        final NetworkRequest request = new NetworkRequest.Builder()
-                .removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VPN)
-                .build();
-        final CountDownLatch latch = new CountDownLatch(1);
-        final NetworkCallback callback = new NetworkCallback() {
-            @Override
-            public void onLinkPropertiesChanged(Network network, LinkProperties lp) {
-                if (network.equals(mNetwork) &&
-                        Objects.equals(lp.getPrivateDnsServerName(), hostname)) {
-                    latch.countDown();
-                }
-            }
-        };
-
-        registerNetworkCallback(request, callback);
-
-        assertTrue("Private DNS hostname was not " + hostname + " after " + TIMEOUT_MS + "ms",
-                latch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
+            // Wait for private DNS setting to propagate.
+            mCtsNetUtils.awaitPrivateDnsSetting("Test wait private DNS setting timeout",
+                    network, hostname, false);
+        }
     }
 
     private void setAndVerifyPrivateDns(boolean strictMode) throws Exception {
diff --git a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
index 9d234d3..b380d02 100644
--- a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
+++ b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
@@ -2112,7 +2112,12 @@
     @AppModeFull(reason = "NETWORK_AIRPLANE_MODE permission can't be granted to instant apps")
     @Test
     public void testSetAirplaneMode() throws Exception{
-        final boolean supportWifi = mPackageManager.hasSystemFeature(FEATURE_WIFI);
+        // Starting from T, wifi supports airplane mode enhancement which may not disconnect wifi
+        // when airplane mode is on. The actual behavior that the device will have could only be
+        // checked with hidden wifi APIs(see Settings.Secure.WIFI_APM_STATE). Thus, stop verifying
+        // wifi on T+ device.
+        final boolean verifyWifi = mPackageManager.hasSystemFeature(FEATURE_WIFI)
+                && !SdkLevel.isAtLeastT();
         final boolean supportTelephony = mPackageManager.hasSystemFeature(FEATURE_TELEPHONY);
         // store the current state of airplane mode
         final boolean isAirplaneModeEnabled = isAirplaneModeEnabled();
@@ -2123,7 +2128,7 @@
         // Verify that networks are available as expected if wifi or cell is supported. Continue the
         // test if none of them are supported since test should still able to verify the permission
         // mechanism.
-        if (supportWifi) {
+        if (verifyWifi) {
             mCtsNetUtils.ensureWifiConnected();
             registerCallbackAndWaitForAvailable(makeWifiNetworkRequest(), wifiCb);
         }
@@ -2147,7 +2152,7 @@
             // Verify that the enabling airplane mode takes effect as expected to prevent flakiness
             // caused by fast airplane mode switches. Ensure network lost before turning off
             // airplane mode.
-            if (supportWifi) waitForLost(wifiCb);
+            if (verifyWifi) waitForLost(wifiCb);
             if (supportTelephony) waitForLost(telephonyCb);
 
             // Verify we can disable Airplane Mode with correct permission:
@@ -2156,7 +2161,7 @@
             // Verify that turning airplane mode off takes effect as expected.
             // connectToCell only registers a request, it cannot / does not need to be called twice
             mCtsNetUtils.ensureWifiConnected();
-            if (supportWifi) waitForAvailable(wifiCb);
+            if (verifyWifi) waitForAvailable(wifiCb);
             if (supportTelephony) waitForAvailable(telephonyCb);
         } finally {
             // Restore the previous state of airplane mode and permissions:
diff --git a/tests/cts/net/src/android/net/cts/MultinetworkApiTest.java b/tests/cts/net/src/android/net/cts/MultinetworkApiTest.java
index 691ab99..17a9ca2 100644
--- a/tests/cts/net/src/android/net/cts/MultinetworkApiTest.java
+++ b/tests/cts/net/src/android/net/cts/MultinetworkApiTest.java
@@ -18,21 +18,18 @@
 
 import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
 
-import android.content.Context;
 import android.content.ContentResolver;
+import android.content.Context;
 import android.net.ConnectivityManager;
 import android.net.Network;
 import android.net.NetworkCapabilities;
 import android.net.NetworkUtils;
 import android.net.cts.util.CtsNetUtils;
 import android.platform.test.annotations.AppModeFull;
-import android.provider.Settings;
 import android.system.ErrnoException;
 import android.system.OsConstants;
 import android.test.AndroidTestCase;
 
-import java.util.ArrayList;
-
 public class MultinetworkApiTest extends AndroidTestCase {
 
     static {
@@ -75,26 +72,8 @@
         super.tearDown();
     }
 
-    private Network[] getTestableNetworks() {
-        final ArrayList<Network> testableNetworks = new ArrayList<Network>();
-        for (Network network : mCM.getAllNetworks()) {
-            final NetworkCapabilities nc = mCM.getNetworkCapabilities(network);
-            if (nc != null
-                    && nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED)
-                    && nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)) {
-                testableNetworks.add(network);
-            }
-        }
-
-        assertTrue(
-                "This test requires that at least one network be connected. " +
-                "Please ensure that the device is connected to a network.",
-                testableNetworks.size() >= 1);
-        return testableNetworks.toArray(new Network[0]);
-    }
-
     public void testGetaddrinfo() throws ErrnoException {
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             int errno = runGetaddrinfoCheck(network.getNetworkHandle());
             if (errno != 0) {
                 throw new ErrnoException(
@@ -109,7 +88,7 @@
         assertNull(mCM.getProcessDefaultNetwork());
         assertEquals(0, NetworkUtils.getBoundNetworkForProcess());
 
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             mCM.setProcessDefaultNetwork(null);
             assertNull(mCM.getProcessDefaultNetwork());
 
@@ -128,7 +107,7 @@
             mCM.setProcessDefaultNetwork(null);
         }
 
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             NetworkUtils.bindProcessToNetwork(0);
             assertNull(mCM.getBoundNetworkForProcess());
 
@@ -148,7 +127,7 @@
 
     @AppModeFull(reason = "CHANGE_NETWORK_STATE permission can't be granted to instant apps")
     public void testSetsocknetwork() throws ErrnoException {
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             int errno = runSetsocknetwork(network.getNetworkHandle());
             if (errno != 0) {
                 throw new ErrnoException(
@@ -158,7 +137,7 @@
     }
 
     public void testNativeDatagramTransmission() throws ErrnoException {
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             int errno = runDatagramCheck(network.getNetworkHandle());
             if (errno != 0) {
                 throw new ErrnoException(
@@ -181,7 +160,7 @@
 
     public void testNetworkHandle() {
         // Test Network -> NetworkHandle -> Network results in the same Network.
-        for (Network network : getTestableNetworks()) {
+        for (Network network : mCtsNetUtils.getTestableNetworks()) {
             long networkHandle = network.getNetworkHandle();
             Network newNetwork = Network.fromNetworkHandle(networkHandle);
             assertEquals(newNetwork, network);
@@ -203,7 +182,7 @@
     }
 
     public void testResNApi() throws Exception {
-        final Network[] testNetworks = getTestableNetworks();
+        final Network[] testNetworks = mCtsNetUtils.getTestableNetworks();
 
         for (Network network : testNetworks) {
             // Throws AssertionError directly in jni function if test fail.
@@ -229,7 +208,7 @@
         // b/144521720
         try {
             mCtsNetUtils.setPrivateDnsStrictMode(GOOGLE_PRIVATE_DNS_SERVER);
-            for (Network network : getTestableNetworks()) {
+            for (Network network : mCtsNetUtils.getTestableNetworks()) {
               // Wait for private DNS setting to propagate.
               mCtsNetUtils.awaitPrivateDnsSetting("NxDomain test wait private DNS setting timeout",
                         network, GOOGLE_PRIVATE_DNS_SERVER, true);
diff --git a/tests/cts/net/util/java/android/net/cts/util/CtsNetUtils.java b/tests/cts/net/util/java/android/net/cts/util/CtsNetUtils.java
index d817630..0c4f794 100644
--- a/tests/cts/net/util/java/android/net/cts/util/CtsNetUtils.java
+++ b/tests/cts/net/util/java/android/net/cts/util/CtsNetUtils.java
@@ -57,6 +57,8 @@
 import android.text.TextUtils;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
+
 import com.android.compatibility.common.util.PollingCheck;
 import com.android.compatibility.common.util.ShellIdentityUtils;
 import com.android.compatibility.common.util.SystemUtil;
@@ -68,6 +70,8 @@
 import java.io.OutputStream;
 import java.net.InetSocketAddress;
 import java.net.Socket;
+import java.util.ArrayList;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
@@ -506,17 +510,18 @@
      * @throws InterruptedException If the thread is interrupted.
      */
     public void awaitPrivateDnsSetting(@NonNull String msg, @NonNull Network network,
-            @NonNull String server, boolean requiresValidatedServer) throws InterruptedException {
+            @Nullable String server, boolean requiresValidatedServer) throws InterruptedException {
         final CountDownLatch latch = new CountDownLatch(1);
         final NetworkRequest request = new NetworkRequest.Builder().clearCapabilities().build();
-        NetworkCallback callback = new NetworkCallback() {
+        final NetworkCallback callback = new NetworkCallback() {
             @Override
             public void onLinkPropertiesChanged(Network n, LinkProperties lp) {
                 Log.i(TAG, "Link properties of network " + n + " changed to " + lp);
                 if (requiresValidatedServer && lp.getValidatedPrivateDnsServers().isEmpty()) {
                     return;
                 }
-                if (network.equals(n) && server.equals(lp.getPrivateDnsServerName())) {
+                Log.i(TAG, "Set private DNS server to " + server);
+                if (network.equals(n) && Objects.equals(server, lp.getPrivateDnsServerName())) {
                     latch.countDown();
                 }
             }
@@ -539,6 +544,27 @@
     }
 
     /**
+     * Get all testable Networks with internet capability.
+     */
+    public Network[] getTestableNetworks() {
+        final ArrayList<Network> testableNetworks = new ArrayList<Network>();
+        for (Network network : mCm.getAllNetworks()) {
+            final NetworkCapabilities nc = mCm.getNetworkCapabilities(network);
+            if (nc != null
+                    && nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED)
+                    && nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)) {
+                testableNetworks.add(network);
+            }
+        }
+
+        assertTrue("This test requires that at least one public Internet-providing"
+                        + " network be connected. Please ensure that the device is connected to"
+                        + " a network.",
+                testableNetworks.size() >= 1);
+        return testableNetworks.toArray(new Network[0]);
+    }
+
+    /**
      * Receiver that captures the last connectivity change's network type and state. Recognizes
      * both {@code CONNECTIVITY_ACTION} and {@code NETWORK_CALLBACK_ACTION} intents.
      */
diff --git a/tests/unit/java/com/android/server/ConnectivityServiceTest.java b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
index 1cc0c89..bd8ac06 100755
--- a/tests/unit/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
@@ -502,7 +502,7 @@
     // complete before callbacks are verified.
     private static final int TEST_REQUEST_TIMEOUT_MS = 150;
 
-    private static final int UNREASONABLY_LONG_ALARM_WAIT_MS = 1000;
+    private static final int UNREASONABLY_LONG_ALARM_WAIT_MS = 2_000;
 
     private static final long TIMESTAMP = 1234L;
 
@@ -1853,7 +1853,7 @@
         final Context mockResContext = mock(Context.class);
         doReturn(mResources).when(mockResContext).getResources();
         ConnectivityResources.setResourcesContextForTest(mockResContext);
-        mDeps = new ConnectivityServiceDependencies(mockResContext);
+        mDeps = spy(new ConnectivityServiceDependencies(mockResContext));
         mAutoOnOffKeepaliveDependencies =
                 new AutomaticOnOffKeepaliveTrackerDependencies(mServiceContext);
         mService = new ConnectivityService(mServiceContext,
@@ -1912,7 +1912,8 @@
                 .getBoolean(R.bool.config_cellular_radio_timesharing_capable);
     }
 
-    class ConnectivityServiceDependencies extends ConnectivityService.Dependencies {
+    // ConnectivityServiceDependencies is public to use Mockito.spy
+    public class ConnectivityServiceDependencies extends ConnectivityService.Dependencies {
         final ConnectivityResources mConnRes;
 
         ConnectivityServiceDependencies(final Context mockResContext) {
@@ -2148,6 +2149,12 @@
                 }
             }
         }
+
+        @Override
+        public void destroyLiveTcpSockets(final Set<Range<Integer>> ranges,
+                final Set<Integer> exemptUids) {
+            // This function is empty since the invocation of this method is verified by mocks
+        }
     }
 
     private class AutomaticOnOffKeepaliveTrackerDependencies
@@ -3369,8 +3376,10 @@
         // This test would be flaky with the default 120ms timer: that is short enough that
         // lingered networks are torn down before assertions can be run. We don't want to mock the
         // lingering timer to keep the WakeupMessage logic realistic: this has already proven useful
-        // in detecting races.
-        mService.mLingerDelayMs = 300;
+        // in detecting races. Furthermore, sometimes the test is running while Phenotype is running
+        // so hot that the test doesn't get the CPU for multiple hundreds of milliseconds, so this
+        // needs to be suitably long.
+        mService.mLingerDelayMs = 2_000;
 
         NetworkRequest request = new NetworkRequest.Builder()
                 .clearCapabilities().addCapability(NET_CAPABILITY_NOT_METERED)
@@ -12469,12 +12478,11 @@
 
     private void assertVpnUidRangesUpdated(boolean add, Set<UidRange> vpnRanges, int exemptUid)
             throws Exception {
-        InOrder inOrder = inOrder(mMockNetd);
-        ArgumentCaptor<int[]> exemptUidCaptor = ArgumentCaptor.forClass(int[].class);
+        InOrder inOrder = inOrder(mMockNetd, mDeps);
+        final Set<Integer> exemptUidSet = new ArraySet<>(List.of(exemptUid, Process.VPN_UID));
 
-        inOrder.verify(mMockNetd, times(1)).socketDestroy(eq(toUidRangeStableParcels(vpnRanges)),
-                exemptUidCaptor.capture());
-        assertContainsExactly(exemptUidCaptor.getValue(), Process.VPN_UID, exemptUid);
+        inOrder.verify(mDeps).destroyLiveTcpSockets(UidRange.toIntRanges(vpnRanges),
+                exemptUidSet);
 
         if (add) {
             inOrder.verify(mMockNetd, times(1)).networkAddUidRangesParcel(
@@ -12486,9 +12494,8 @@
                             toUidRangeStableParcels(vpnRanges), PREFERENCE_ORDER_VPN));
         }
 
-        inOrder.verify(mMockNetd, times(1)).socketDestroy(eq(toUidRangeStableParcels(vpnRanges)),
-                exemptUidCaptor.capture());
-        assertContainsExactly(exemptUidCaptor.getValue(), Process.VPN_UID, exemptUid);
+        inOrder.verify(mDeps).destroyLiveTcpSockets(UidRange.toIntRanges(vpnRanges),
+                exemptUidSet);
     }
 
     @Test
diff --git a/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java b/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
index b651c33..4158663 100644
--- a/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
+++ b/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
@@ -313,8 +313,7 @@
          * Stop clatd.
          */
         @Override
-        public void stopClatd(@NonNull String iface, @NonNull String pfx96, @NonNull String v4,
-                @NonNull String v6, int pid) throws IOException {
+        public void stopClatd(int pid) throws IOException {
             if (pid == -1) {
                 fail("unsupported arg: " + pid);
             }
@@ -479,8 +478,7 @@
                 eq((short) PRIO_CLAT), eq((short) ETH_P_IP));
         inOrder.verify(mEgressMap).deleteEntry(eq(EGRESS_KEY));
         inOrder.verify(mIngressMap).deleteEntry(eq(INGRESS_KEY));
-        inOrder.verify(mDeps).stopClatd(eq(BASE_IFACE), eq(NAT64_PREFIX_STRING),
-                eq(XLAT_LOCAL_IPV4ADDR_STRING), eq(XLAT_LOCAL_IPV6ADDR_STRING), eq(CLATD_PID));
+        inOrder.verify(mDeps).stopClatd(eq(CLATD_PID));
         inOrder.verify(mCookieTagMap).deleteEntry(eq(COOKIE_TAG_KEY));
         assertNull(coordinator.getClatdTrackerForTesting());
         inOrder.verifyNoMoreInteractions();
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceCacheTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceCacheTest.kt
new file mode 100644
index 0000000..f091eea
--- /dev/null
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceCacheTest.kt
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2023 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.connectivity.mdns
+
+import android.net.Network
+import android.os.Build
+import android.os.Handler
+import android.os.HandlerThread
+import com.android.testutils.DevSdkIgnoreRule
+import com.android.testutils.DevSdkIgnoreRunner
+import java.util.concurrent.CompletableFuture
+import java.util.concurrent.TimeUnit
+import kotlin.test.assertNotNull
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mockito.mock
+
+private const val SERVICE_NAME_1 = "service-instance-1"
+private const val SERVICE_NAME_2 = "service-instance-2"
+private const val SERVICE_TYPE_1 = "_test1._tcp.local"
+private const val SERVICE_TYPE_2 = "_test2._tcp.local"
+private const val INTERFACE_INDEX = 999
+private const val DEFAULT_TIMEOUT_MS = 2000L
+
+@RunWith(DevSdkIgnoreRunner::class)
+@DevSdkIgnoreRule.IgnoreUpTo(Build.VERSION_CODES.S_V2)
+class MdnsServiceCacheTest {
+    private val network = mock(Network::class.java)
+    private val thread = HandlerThread(MdnsServiceCacheTest::class.simpleName)
+    private val handler by lazy {
+        Handler(thread.looper)
+    }
+    private val serviceCache by lazy {
+        MdnsServiceCache(thread.looper)
+    }
+
+    @Before
+    fun setUp() {
+        thread.start()
+    }
+
+    @After
+    fun tearDown() {
+        thread.quitSafely()
+    }
+
+    private fun <T> runningOnHandlerAndReturn(functor: (() -> T)): T {
+        val future = CompletableFuture<T>()
+        handler.post {
+            future.complete(functor())
+        }
+        return future.get(DEFAULT_TIMEOUT_MS, TimeUnit.MILLISECONDS)
+    }
+
+    private fun addOrUpdateService(serviceType: String, network: Network, service: MdnsResponse):
+            Unit = runningOnHandlerAndReturn {
+        serviceCache.addOrUpdateService(serviceType, network, service) }
+
+    private fun removeService(serviceName: String, serviceType: String, network: Network):
+            Unit = runningOnHandlerAndReturn {
+        serviceCache.removeService(serviceName, serviceType, network) }
+
+    private fun getService(serviceName: String, serviceType: String, network: Network):
+            MdnsResponse? = runningOnHandlerAndReturn {
+        serviceCache.getCachedService(serviceName, serviceType, network) }
+
+    private fun getServices(serviceType: String, network: Network): List<MdnsResponse> =
+        runningOnHandlerAndReturn { serviceCache.getCachedServices(serviceType, network) }
+
+    @Test
+    fun testAddAndRemoveService() {
+        addOrUpdateService(SERVICE_TYPE_1, network, createResponse(SERVICE_NAME_1, SERVICE_TYPE_1))
+        var response = getService(SERVICE_NAME_1, SERVICE_TYPE_1, network)
+        assertNotNull(response)
+        assertEquals(SERVICE_NAME_1, response.serviceInstanceName)
+        removeService(SERVICE_NAME_1, SERVICE_TYPE_1, network)
+        response = getService(SERVICE_NAME_1, SERVICE_TYPE_1, network)
+        assertNull(response)
+    }
+
+    @Test
+    fun testGetCachedServices_multipleServiceTypes() {
+        addOrUpdateService(SERVICE_TYPE_1, network, createResponse(SERVICE_NAME_1, SERVICE_TYPE_1))
+        addOrUpdateService(SERVICE_TYPE_1, network, createResponse(SERVICE_NAME_2, SERVICE_TYPE_1))
+        addOrUpdateService(SERVICE_TYPE_2, network, createResponse(SERVICE_NAME_2, SERVICE_TYPE_2))
+
+        val responses1 = getServices(SERVICE_TYPE_1, network)
+        assertEquals(2, responses1.size)
+        assertTrue(responses1.stream().anyMatch { response ->
+            response.serviceInstanceName == SERVICE_NAME_1
+        })
+        assertTrue(responses1.any { response ->
+            response.serviceInstanceName == SERVICE_NAME_2
+        })
+        val responses2 = getServices(SERVICE_TYPE_2, network)
+        assertEquals(1, responses2.size)
+        assertTrue(responses2.any { response ->
+            response.serviceInstanceName == SERVICE_NAME_2
+        })
+
+        removeService(SERVICE_NAME_2, SERVICE_TYPE_1, network)
+        val responses3 = getServices(SERVICE_TYPE_1, network)
+        assertEquals(1, responses3.size)
+        assertTrue(responses3.any { response ->
+            response.serviceInstanceName == SERVICE_NAME_1
+        })
+        val responses4 = getServices(SERVICE_TYPE_2, network)
+        assertEquals(1, responses4.size)
+        assertTrue(responses4.any { response ->
+            response.serviceInstanceName == SERVICE_NAME_2
+        })
+    }
+
+    private fun createResponse(serviceInstanceName: String, serviceType: String) = MdnsResponse(
+        0 /* now */, "$serviceInstanceName.$serviceType".split(".").toTypedArray(),
+            INTERFACE_INDEX, network)
+}
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/util/MdnsUtilsTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/util/MdnsUtilsTest.kt
new file mode 100644
index 0000000..f584ed5
--- /dev/null
+++ b/tests/unit/java/com/android/server/connectivity/mdns/util/MdnsUtilsTest.kt
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2023 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.connectivity.mdns.util
+
+import android.os.Build
+import com.android.server.connectivity.mdns.util.MdnsUtils.equalsIgnoreDnsCase
+import com.android.server.connectivity.mdns.util.MdnsUtils.toDnsLowerCase
+import com.android.testutils.DevSdkIgnoreRule
+import com.android.testutils.DevSdkIgnoreRunner
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(DevSdkIgnoreRunner::class)
+@DevSdkIgnoreRule.IgnoreUpTo(Build.VERSION_CODES.S_V2)
+class MdnsUtilsTest {
+    @Test
+    fun testToDnsLowerCase() {
+        assertEquals("test", toDnsLowerCase("TEST"))
+        assertEquals("test", toDnsLowerCase("TeSt"))
+        assertEquals("test", toDnsLowerCase("test"))
+        assertEquals("tÉst", toDnsLowerCase("TÉST"))
+        assertEquals("ţést", toDnsLowerCase("ţést"))
+        // Unicode characters 0x10000 (𐀀), 0x10001 (𐀁), 0x10041 (𐁁)
+        // Note the last 2 bytes of 0x10041 are identical to 'A', but it should remain unchanged.
+        assertEquals("test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- ",
+                toDnsLowerCase("Test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- "))
+        // Also test some characters where the first surrogate is not \ud800
+        assertEquals("test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
+                "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<",
+                toDnsLowerCase("Test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
+                        "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<"))
+    }
+
+    @Test
+    fun testEqualsIgnoreDnsCase() {
+        assertTrue(equalsIgnoreDnsCase("TEST", "Test"))
+        assertTrue(equalsIgnoreDnsCase("TEST", "test"))
+        assertTrue(equalsIgnoreDnsCase("test", "TeSt"))
+        assertTrue(equalsIgnoreDnsCase("Tést", "tést"))
+        assertFalse(equalsIgnoreDnsCase("ŢÉST", "ţést"))
+        // Unicode characters 0x10000 (𐀀), 0x10001 (𐀁), 0x10041 (𐁁)
+        // Note the last 2 bytes of 0x10041 are identical to 'A', but it should remain unchanged.
+        assertTrue(equalsIgnoreDnsCase("test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- ",
+                "Test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- "))
+        // Also test some characters where the first surrogate is not \ud800
+        assertTrue(equalsIgnoreDnsCase("test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
+                "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<",
+                "Test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
+                        "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<"))
+    }
+}