diff --git a/framework/Android.bp b/framework/Android.bp
index c91017f..4fa9ccb 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -108,10 +108,8 @@
         "-Wthread-safety",
     ],
     shared_libs: [
-        "libbase",
         "liblog",
         "libnativehelper",
-        "libnetd_client",
     ],
     header_libs: [
         "dnsproxyd_protocol_headers",
@@ -124,6 +122,7 @@
     srcs: [
         "jni/android_net_NetworkUtils.cpp",
     ],
+    shared_libs: ["libandroid_net"],
     apex_available: [
         "//apex_available:platform",
         "com.android.tethering",
@@ -134,9 +133,11 @@
     name: "libframework-connectivity-jni",
     defaults: ["libframework-connectivity-defaults"],
     srcs: [
+        "jni/android_net_NetworkUtils.cpp",
         "jni/onload.cpp",
     ],
-    static_libs: ["libconnectivityframeworkutils"],
+    shared_libs: ["libandroid"],
+    stl: "libc++_static",
     apex_available: [
         "//apex_available:platform",
         "com.android.tethering",
diff --git a/framework/jni/android_net_NetworkUtils.cpp b/framework/jni/android_net_NetworkUtils.cpp
index f17baf9..26484fb 100644
--- a/framework/jni/android_net_NetworkUtils.cpp
+++ b/framework/jni/android_net_NetworkUtils.cpp
@@ -19,6 +19,7 @@
 #include <vector>
 
 #include <android/file_descriptor_jni.h>
+#include <android/multinetwork.h>
 #include <arpa/inet.h>
 #include <linux/filter.h>
 #include <linux/if_arp.h>
@@ -36,7 +37,6 @@
 #include <utils/Log.h>
 #include <utils/misc.h>
 
-#include "NetdClient.h"
 #include "jni.h"
 
 extern "C" {
@@ -94,25 +94,32 @@
     }
 }
 
-static jboolean android_net_utils_bindProcessToNetwork(JNIEnv *env, jobject thiz, jint netId)
+static jboolean android_net_utils_bindProcessToNetworkHandle(JNIEnv *env, jobject thiz,
+        jlong netHandle)
 {
-    return (jboolean) !setNetworkForProcess(netId);
+    return (jboolean) !android_setprocnetwork(netHandle);
 }
 
-static jint android_net_utils_getBoundNetworkForProcess(JNIEnv *env, jobject thiz)
+static jlong android_net_utils_getBoundNetworkHandleForProcess(JNIEnv *env, jobject thiz)
 {
-    return getNetworkForProcess();
+    net_handle_t network;
+    if (android_getprocnetwork(&network) != 0) {
+        jniThrowExceptionFmt(env, "java/lang/IllegalStateException",
+                "android_getprocnetwork(): %s", strerror(errno));
+        return NETWORK_UNSPECIFIED;
+    }
+    return (jlong) network;
 }
 
 static jboolean android_net_utils_bindProcessToNetworkForHostResolution(JNIEnv *env, jobject thiz,
-        jint netId)
+        jint netId, jlong netHandle)
 {
-    return (jboolean) !setNetworkForResolv(netId);
+    return (jboolean) !android_setprocdns(netHandle);
 }
 
-static jint android_net_utils_bindSocketToNetwork(JNIEnv *env, jobject thiz, jobject javaFd,
-                                                  jint netId) {
-    return setNetworkForSocket(netId, AFileDescriptor_getFd(env, javaFd));
+static jint android_net_utils_bindSocketToNetworkHandle(JNIEnv *env, jobject thiz, jobject javaFd,
+                                                  jlong netHandle) {
+    return android_setsocknetwork(netHandle, AFileDescriptor_getFd(env, javaFd));
 }
 
 static bool checkLenAndCopy(JNIEnv* env, const jbyteArray& addr, int len, void* dst)
@@ -124,7 +131,7 @@
     return true;
 }
 
-static jobject android_net_utils_resNetworkQuery(JNIEnv *env, jobject thiz, jint netId,
+static jobject android_net_utils_resNetworkQuery(JNIEnv *env, jobject thiz, jlong netHandle,
         jstring dname, jint ns_class, jint ns_type, jint flags) {
     const jsize javaCharsCount = env->GetStringLength(dname);
     const jsize byteCountUTF8 = env->GetStringUTFLength(dname);
@@ -134,7 +141,8 @@
     std::vector<char> queryname(byteCountUTF8 + 1, 0);
 
     env->GetStringUTFRegion(dname, 0, javaCharsCount, queryname.data());
-    int fd = resNetworkQuery(netId, queryname.data(), ns_class, ns_type, flags);
+
+    int fd = android_res_nquery(netHandle, queryname.data(), ns_class, ns_type, flags);
 
     if (fd < 0) {
         jniThrowErrnoException(env, "resNetworkQuery", -fd);
@@ -144,12 +152,12 @@
     return jniCreateFileDescriptor(env, fd);
 }
 
-static jobject android_net_utils_resNetworkSend(JNIEnv *env, jobject thiz, jint netId,
+static jobject android_net_utils_resNetworkSend(JNIEnv *env, jobject thiz, jlong netHandle,
         jbyteArray msg, jint msgLen, jint flags) {
     uint8_t data[MAXCMDSIZE];
 
     checkLenAndCopy(env, msg, msgLen, data);
-    int fd = resNetworkSend(netId, data, msgLen, flags);
+    int fd = android_res_nsend(netHandle, data, msgLen, flags);
 
     if (fd < 0) {
         jniThrowErrnoException(env, "resNetworkSend", -fd);
@@ -164,7 +172,7 @@
     int rcode;
     std::vector<uint8_t> buf(MAXPACKETSIZE, 0);
 
-    int res = resNetworkResult(fd, &rcode, buf.data(), MAXPACKETSIZE);
+    int res = android_res_nresult(fd, &rcode, buf.data(), MAXPACKETSIZE);
     jniSetFileDescriptorOfFD(env, javaFd, -1);
     if (res < 0) {
         jniThrowErrnoException(env, "resNetworkResult", -res);
@@ -188,23 +196,22 @@
 
 static void android_net_utils_resNetworkCancel(JNIEnv *env, jobject thiz, jobject javaFd) {
     int fd = AFileDescriptor_getFd(env, javaFd);
-    resNetworkCancel(fd);
+    android_res_cancel(fd);
     jniSetFileDescriptorOfFD(env, javaFd, -1);
 }
 
 static jobject android_net_utils_getDnsNetwork(JNIEnv *env, jobject thiz) {
-    unsigned dnsNetId = 0;
-    if (int res = getNetworkForDns(&dnsNetId) < 0) {
-        jniThrowErrnoException(env, "getDnsNetId", -res);
+    net_handle_t dnsNetHandle = NETWORK_UNSPECIFIED;
+    if (int res = android_getprocdns(&dnsNetHandle) < 0) {
+        jniThrowErrnoException(env, "getDnsNetwork", -res);
         return nullptr;
     }
-    bool privateDnsBypass = dnsNetId & NETID_USE_LOCAL_NAMESERVERS;
 
     static jclass class_Network = MakeGlobalRefOrDie(
             env, FindClassOrDie(env, "android/net/Network"));
-    static jmethodID ctor = env->GetMethodID(class_Network, "<init>", "(IZ)V");
-    return env->NewObject(
-            class_Network, ctor, dnsNetId & ~NETID_USE_LOCAL_NAMESERVERS, privateDnsBypass);
+    static jmethodID method = env->GetStaticMethodID(class_Network, "fromNetworkHandle",
+            "(J)Landroid/net/Network;");
+    return env->CallStaticObjectMethod(class_Network, method, static_cast<jlong>(dnsNetHandle));
 }
 
 static jobject android_net_utils_getTcpRepairWindow(JNIEnv *env, jobject thiz, jobject javaFd) {
@@ -250,15 +257,15 @@
 // clang-format off
 static const JNINativeMethod gNetworkUtilMethods[] = {
     /* name, signature, funcPtr */
-    { "bindProcessToNetwork", "(I)Z", (void*) android_net_utils_bindProcessToNetwork },
-    { "getBoundNetworkForProcess", "()I", (void*) android_net_utils_getBoundNetworkForProcess },
+    { "bindProcessToNetworkHandle", "(J)Z", (void*) android_net_utils_bindProcessToNetworkHandle },
+    { "getBoundNetworkHandleForProcess", "()J", (void*) android_net_utils_getBoundNetworkHandleForProcess },
     { "bindProcessToNetworkForHostResolution", "(I)Z", (void*) android_net_utils_bindProcessToNetworkForHostResolution },
-    { "bindSocketToNetwork", "(Ljava/io/FileDescriptor;I)I", (void*) android_net_utils_bindSocketToNetwork },
+    { "bindSocketToNetworkHandle", "(Ljava/io/FileDescriptor;J)I", (void*) android_net_utils_bindSocketToNetworkHandle },
     { "attachDropAllBPFFilter", "(Ljava/io/FileDescriptor;)V", (void*) android_net_utils_attachDropAllBPFFilter },
     { "detachBPFFilter", "(Ljava/io/FileDescriptor;)V", (void*) android_net_utils_detachBPFFilter },
     { "getTcpRepairWindow", "(Ljava/io/FileDescriptor;)Landroid/net/TcpRepairWindow;", (void*) android_net_utils_getTcpRepairWindow },
-    { "resNetworkSend", "(I[BII)Ljava/io/FileDescriptor;", (void*) android_net_utils_resNetworkSend },
-    { "resNetworkQuery", "(ILjava/lang/String;III)Ljava/io/FileDescriptor;", (void*) android_net_utils_resNetworkQuery },
+    { "resNetworkSend", "(J[BII)Ljava/io/FileDescriptor;", (void*) android_net_utils_resNetworkSend },
+    { "resNetworkQuery", "(JLjava/lang/String;III)Ljava/io/FileDescriptor;", (void*) android_net_utils_resNetworkQuery },
     { "resNetworkResult", "(Ljava/io/FileDescriptor;)Landroid/net/DnsResolver$DnsResponse;", (void*) android_net_utils_resNetworkResult },
     { "resNetworkCancel", "(Ljava/io/FileDescriptor;)V", (void*) android_net_utils_resNetworkCancel },
     { "getDnsNetwork", "()Landroid/net/Network;", (void*) android_net_utils_getDnsNetwork },
diff --git a/framework/src/android/net/Network.java b/framework/src/android/net/Network.java
index 41fad63..1f49033 100644
--- a/framework/src/android/net/Network.java
+++ b/framework/src/android/net/Network.java
@@ -92,6 +92,7 @@
     // value in the native/android/net.c NDK implementation.
     private static final long HANDLE_MAGIC = 0xcafed00dL;
     private static final int HANDLE_MAGIC_SIZE = 32;
+    private static final int USE_LOCAL_NAMESERVERS_FLAG = 0x80000000;
 
     // A boolean to control how getAllByName()/getByName() behaves in the face
     // of Private DNS.
@@ -189,7 +190,7 @@
      */
     public int getNetIdForResolv() {
         return mPrivateDnsBypass
-                ? (int) (0x80000000L | (long) netId)  // Non-portable DNS resolution flag.
+                ? (USE_LOCAL_NAMESERVERS_FLAG | netId)  // Non-portable DNS resolution flag.
                 : netId;
     }
 
@@ -452,12 +453,13 @@
             throw new IllegalArgumentException(
                     "Network.fromNetworkHandle refusing to instantiate NETID_UNSET Network.");
         }
-        if ((networkHandle & ((1L << HANDLE_MAGIC_SIZE) - 1)) != HANDLE_MAGIC
-                || networkHandle < 0) {
+        if ((networkHandle & ((1L << HANDLE_MAGIC_SIZE) - 1)) != HANDLE_MAGIC) {
             throw new IllegalArgumentException(
                     "Value passed to fromNetworkHandle() is not a network handle.");
         }
-        return new Network((int) (networkHandle >> HANDLE_MAGIC_SIZE));
+        final int netIdForResolv = (int) (networkHandle >>> HANDLE_MAGIC_SIZE);
+        return new Network((netIdForResolv & ~USE_LOCAL_NAMESERVERS_FLAG),
+                ((netIdForResolv & USE_LOCAL_NAMESERVERS_FLAG) != 0) /* privateDnsBypass */);
     }
 
     /**
@@ -485,7 +487,7 @@
         if (netId == 0) {
             return 0L;  // make this zero condition obvious for debugging
         }
-        return (((long) netId) << HANDLE_MAGIC_SIZE) | HANDLE_MAGIC;
+        return (((long) getNetIdForResolv()) << HANDLE_MAGIC_SIZE) | HANDLE_MAGIC;
     }
 
     // implement the Parcelable interface
diff --git a/framework/src/android/net/NetworkUtils.java b/framework/src/android/net/NetworkUtils.java
index a92fda1..16a49bc 100644
--- a/framework/src/android/net/NetworkUtils.java
+++ b/framework/src/android/net/NetworkUtils.java
@@ -16,6 +16,8 @@
 
 package android.net;
 
+import static android.net.ConnectivityManager.NETID_UNSET;
+
 import android.compat.annotation.UnsupportedAppUsage;
 import android.os.Build;
 import android.system.ErrnoException;
@@ -55,6 +57,8 @@
      */
     public static native void detachBPFFilter(FileDescriptor fd) throws SocketException;
 
+    private static native boolean bindProcessToNetworkHandle(long netHandle);
+
     /**
      * Binds the current process to the network designated by {@code netId}.  All sockets created
      * in the future (and not explicitly bound via a bound {@link SocketFactory} (see
@@ -63,13 +67,20 @@
      * is by design so an application doesn't accidentally use sockets it thinks are still bound to
      * a particular {@code Network}.  Passing NETID_UNSET clears the binding.
      */
-    public native static boolean bindProcessToNetwork(int netId);
+    public static boolean bindProcessToNetwork(int netId) {
+        return bindProcessToNetworkHandle(new Network(netId).getNetworkHandle());
+    }
+
+    private static native long getBoundNetworkHandleForProcess();
 
     /**
      * Return the netId last passed to {@link #bindProcessToNetwork}, or NETID_UNSET if
      * {@link #unbindProcessToNetwork} has been called since {@link #bindProcessToNetwork}.
      */
-    public native static int getBoundNetworkForProcess();
+    public static int getBoundNetworkForProcess() {
+        final long netHandle = getBoundNetworkHandleForProcess();
+        return netHandle == 0L ? NETID_UNSET : Network.fromNetworkHandle(netHandle).getNetId();
+    }
 
     /**
      * Binds host resolutions performed by this process to the network designated by {@code netId}.
@@ -81,12 +92,16 @@
     @Deprecated
     public native static boolean bindProcessToNetworkForHostResolution(int netId);
 
+    private static native int bindSocketToNetworkHandle(FileDescriptor fd, long netHandle);
+
     /**
      * Explicitly binds {@code fd} to the network designated by {@code netId}.  This
      * overrides any binding via {@link #bindProcessToNetwork}.
      * @return 0 on success or negative errno on failure.
      */
-    public static native int bindSocketToNetwork(FileDescriptor fd, int netId);
+    public static int bindSocketToNetwork(FileDescriptor fd, int netId) {
+        return bindSocketToNetworkHandle(fd, new Network(netId).getNetworkHandle());
+    }
 
     /**
      * Determine if {@code uid} can access network designated by {@code netId}.
@@ -97,14 +112,22 @@
         return false;
     }
 
+    private static native FileDescriptor resNetworkSend(
+            long netHandle, byte[] msg, int msglen, int flags) throws ErrnoException;
+
     /**
      * DNS resolver series jni method.
      * Issue the query {@code msg} on the network designated by {@code netId}.
      * {@code flags} is an additional config to control actual querying behavior.
      * @return a file descriptor to watch for read events
      */
-    public static native FileDescriptor resNetworkSend(
-            int netId, byte[] msg, int msglen, int flags) throws ErrnoException;
+    public static FileDescriptor resNetworkSend(
+            int netId, byte[] msg, int msglen, int flags) throws ErrnoException {
+        return resNetworkSend(new Network(netId).getNetworkHandle(), msg, msglen, flags);
+    }
+
+    private static native FileDescriptor resNetworkQuery(
+            long netHandle, String dname, int nsClass, int nsType, int flags) throws ErrnoException;
 
     /**
      * DNS resolver series jni method.
@@ -113,8 +136,11 @@
      * {@code flags} is an additional config to control actual querying behavior.
      * @return a file descriptor to watch for read events
      */
-    public static native FileDescriptor resNetworkQuery(
-            int netId, String dname, int nsClass, int nsType, int flags) throws ErrnoException;
+    public static FileDescriptor resNetworkQuery(
+            int netId, String dname, int nsClass, int nsType, int flags) throws ErrnoException {
+        return resNetworkQuery(new Network(netId).getNetworkHandle(), dname, nsClass, nsType,
+                flags);
+    }
 
     /**
      * DNS resolver series jni method.
diff --git a/service/Android.bp b/service/Android.bp
index b6adf79..8c46dea 100644
--- a/service/Android.bp
+++ b/service/Android.bp
@@ -32,6 +32,7 @@
         "jni/com_android_server_TestNetworkService.cpp",
         "jni/onload.cpp",
     ],
+    stl: "libc++_static",
     shared_libs: [
         "libbase",
         "liblog",
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index 842ad62..adfcace 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -87,7 +87,6 @@
 import static java.util.Map.Entry;
 
 import android.Manifest;
-import android.annotation.BoolRes;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.AppOpsManager;
@@ -150,7 +149,6 @@
 import android.net.NetworkScore;
 import android.net.NetworkSpecifier;
 import android.net.NetworkStack;
-import android.net.NetworkStackClient;
 import android.net.NetworkState;
 import android.net.NetworkStateSnapshot;
 import android.net.NetworkTestResultParcelable;
@@ -177,13 +175,14 @@
 import android.net.metrics.IpConnectivityLog;
 import android.net.metrics.NetworkEvent;
 import android.net.netlink.InetDiagMessage;
+import android.net.networkstack.ModuleNetworkStackClient;
+import android.net.networkstack.NetworkStackClientBase;
 import android.net.resolv.aidl.DnsHealthEventParcel;
 import android.net.resolv.aidl.IDnsResolverUnsolicitedEventListener;
 import android.net.resolv.aidl.Nat64PrefixEventParcel;
 import android.net.resolv.aidl.PrivateDnsValidationEventParcel;
 import android.net.shared.PrivateDnsConfig;
 import android.net.util.MultinetworkPolicyTracker;
-import android.net.util.NetdService;
 import android.os.BatteryStatsManager;
 import android.os.Binder;
 import android.os.Build;
@@ -1184,10 +1183,10 @@
         }
 
         /**
-         * Get a reference to the NetworkStackClient.
+         * Get a reference to the ModuleNetworkStackClient.
          */
-        public NetworkStackClient getNetworkStack() {
-            return NetworkStackClient.getInstance();
+        public NetworkStackClientBase getNetworkStack() {
+            return ModuleNetworkStackClient.getInstance(null);
         }
 
         /**
@@ -1246,7 +1245,8 @@
 
     public ConnectivityService(Context context) {
         this(context, getDnsResolver(context), new IpConnectivityLog(),
-                NetdService.getInstance(), new Dependencies());
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
+                new Dependencies());
     }
 
     @VisibleForTesting
@@ -1460,7 +1460,7 @@
         mHandler.sendEmptyMessage(EVENT_PRIVATE_DNS_SETTINGS_CHANGED);
     }
 
-    private void handleAlwaysOnNetworkRequest(NetworkRequest networkRequest, @BoolRes int id) {
+    private void handleAlwaysOnNetworkRequest(NetworkRequest networkRequest, int id) {
         final boolean enable = mContext.getResources().getBoolean(id);
         handleAlwaysOnNetworkRequest(networkRequest, enable);
     }
@@ -2989,10 +2989,6 @@
         }
 
         pw.println();
-        pw.println("NetworkStackClient logs:");
-        pw.increaseIndent();
-        NetworkStackClient.getInstance().dump(pw);
-        pw.decreaseIndent();
 
         pw.println();
         pw.println("Permission Monitor:");
@@ -8777,7 +8773,7 @@
         }
     }
 
-    private @VpnManager.VpnType int getVpnType(@Nullable NetworkAgentInfo vpn) {
+    private int getVpnType(@Nullable NetworkAgentInfo vpn) {
         if (vpn == null) return VpnManager.TYPE_VPN_NONE;
         final TransportInfo ti = vpn.networkCapabilities.getTransportInfo();
         if (!(ti instanceof VpnTransportInfo)) return VpnManager.TYPE_VPN_NONE;
diff --git a/service/src/com/android/server/TestNetworkService.java b/service/src/com/android/server/TestNetworkService.java
index f566277..09873f4 100644
--- a/service/src/com/android/server/TestNetworkService.java
+++ b/service/src/com/android/server/TestNetworkService.java
@@ -35,7 +35,6 @@
 import android.net.RouteInfo;
 import android.net.TestNetworkInterface;
 import android.net.TestNetworkSpecifier;
-import android.net.util.NetdService;
 import android.os.Binder;
 import android.os.Handler;
 import android.os.HandlerThread;
@@ -86,7 +85,9 @@
         mHandler = new Handler(mHandlerThread.getLooper());
 
         mContext = Objects.requireNonNull(context, "missing Context");
-        mNetd = Objects.requireNonNull(NetdService.getInstance(), "could not get netd instance");
+        mNetd = Objects.requireNonNull(
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
+                "could not get netd instance");
         mCm = mContext.getSystemService(ConnectivityManager.class);
         mNetworkProvider = new NetworkProvider(mContext, mHandler.getLooper(),
                 TEST_NETWORK_PROVIDER_NAME);
diff --git a/service/src/com/android/server/connectivity/NetworkNotificationManager.java b/service/src/com/android/server/connectivity/NetworkNotificationManager.java
index 0c0d459..b57ad5d 100644
--- a/service/src/com/android/server/connectivity/NetworkNotificationManager.java
+++ b/service/src/com/android/server/connectivity/NetworkNotificationManager.java
@@ -84,7 +84,7 @@
 
     // The context is for the current user (system server)
     private final Context mContext;
-    private final Resources mResources;
+    private final ConnectivityResources mResources;
     private final TelephonyManager mTelephonyManager;
     // The notification manager is created from a context for User.ALL, so notifications
     // will be sent to all users.
@@ -99,7 +99,7 @@
                 (NotificationManager) c.createContextAsUser(UserHandle.ALL, 0 /* flags */)
                         .getSystemService(Context.NOTIFICATION_SERVICE);
         mNotificationTypeMap = new SparseIntArray();
-        mResources = new ConnectivityResources(mContext).get();
+        mResources = new ConnectivityResources(mContext);
     }
 
     @VisibleForTesting
@@ -118,11 +118,11 @@
     }
 
     private String getTransportName(final int transportType) {
-        String[] networkTypes = mResources.getStringArray(R.array.network_switch_type_name);
+        String[] networkTypes = mResources.get().getStringArray(R.array.network_switch_type_name);
         try {
             return networkTypes[transportType];
         } catch (IndexOutOfBoundsException e) {
-            return mResources.getString(R.string.network_switch_type_name_unknown);
+            return mResources.get().getString(R.string.network_switch_type_name_unknown);
         }
     }
 
@@ -197,10 +197,11 @@
                     tag, nameOf(eventId), getTransportName(transportType), name, highPriority));
         }
 
-        final Resources r = mResources;
+        final Resources r = mResources.get();
         final CharSequence title;
         final CharSequence details;
-        Icon icon = Icon.createWithResource(r, getIcon(transportType));
+        Icon icon = Icon.createWithResource(
+                mResources.getResourcesContext(), getIcon(transportType));
         if (notifyType == NotificationType.NO_INTERNET && transportType == TRANSPORT_WIFI) {
             title = r.getString(R.string.wifi_no_internet, name);
             details = r.getString(R.string.wifi_no_internet_detailed);
@@ -355,7 +356,7 @@
     public void showToast(NetworkAgentInfo fromNai, NetworkAgentInfo toNai) {
         String fromTransport = getTransportName(approximateTransportType(fromNai));
         String toTransport = getTransportName(approximateTransportType(toNai));
-        String text = mResources.getString(
+        String text = mResources.get().getString(
                 R.string.network_switch_metered_toast, fromTransport, toTransport);
         Toast.makeText(mContext, text, Toast.LENGTH_LONG).show();
     }
diff --git a/service/src/com/android/server/connectivity/OsCompat.java b/service/src/com/android/server/connectivity/OsCompat.java
new file mode 100644
index 0000000..57e3dcd
--- /dev/null
+++ b/service/src/com/android/server/connectivity/OsCompat.java
@@ -0,0 +1,75 @@
+/*
+ * 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.connectivity;
+
+import android.system.ErrnoException;
+import android.system.Os;
+
+import java.io.FileDescriptor;
+
+/**
+ * Compatibility utility for android.system.Os core platform APIs.
+ *
+ * Connectivity has access to such APIs, but they are not part of the module_current stubs yet
+ * (only core_current). Most stable core platform APIs are included manually in the connectivity
+ * build rules, but because Os is also part of the base java SDK that is earlier on the
+ * classpath, the extra core platform APIs are not seen.
+ *
+ * TODO (b/157639992, b/183097033): remove as soon as core_current is part of system_server_current
+ * @hide
+ */
+public class OsCompat {
+    // This value should be correct on all architectures supported by Android, but hardcoding ioctl
+    // numbers should be avoided.
+    /**
+     * @see android.system.OsConstants#TIOCOUTQ
+     */
+    public static final int TIOCOUTQ = 0x5411;
+
+    /**
+     * @see android.system.Os#getsockoptInt(FileDescriptor, int, int)
+     */
+    public static int getsockoptInt(FileDescriptor fd, int level, int option) throws
+            ErrnoException {
+        try {
+            return (int) Os.class.getMethod(
+                    "getsockoptInt", FileDescriptor.class, int.class, int.class)
+                    .invoke(null, fd, level, option);
+        } catch (ReflectiveOperationException e) {
+            if (e.getCause() instanceof ErrnoException) {
+                throw (ErrnoException) e.getCause();
+            }
+            throw new IllegalStateException("Error calling getsockoptInt", e);
+        }
+    }
+
+    /**
+     * @see android.system.Os#ioctlInt(FileDescriptor, int)
+     */
+    public static int ioctlInt(FileDescriptor fd, int cmd) throws
+            ErrnoException {
+        try {
+            return (int) Os.class.getMethod(
+                    "ioctlInt", FileDescriptor.class, int.class).invoke(null, fd, cmd);
+        } catch (ReflectiveOperationException e) {
+            if (e.getCause() instanceof ErrnoException) {
+                throw (ErrnoException) e.getCause();
+            }
+            throw new IllegalStateException("Error calling ioctlInt", e);
+        }
+    }
+}
diff --git a/service/src/com/android/server/connectivity/TcpKeepaliveController.java b/service/src/com/android/server/connectivity/TcpKeepaliveController.java
index c480594..73f3475 100644
--- a/service/src/com/android/server/connectivity/TcpKeepaliveController.java
+++ b/service/src/com/android/server/connectivity/TcpKeepaliveController.java
@@ -27,7 +27,8 @@
 import static android.system.OsConstants.IPPROTO_TCP;
 import static android.system.OsConstants.IP_TOS;
 import static android.system.OsConstants.IP_TTL;
-import static android.system.OsConstants.TIOCOUTQ;
+
+import static com.android.server.connectivity.OsCompat.TIOCOUTQ;
 
 import android.annotation.NonNull;
 import android.net.InvalidPacketException;
@@ -175,10 +176,10 @@
             }
             // Query write sequence number from SEND_QUEUE.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_SEND_QUEUE);
-            tcpDetails.seq = Os.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
+            tcpDetails.seq = OsCompat.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
             // Query read sequence number from RECV_QUEUE.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_RECV_QUEUE);
-            tcpDetails.ack = Os.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
+            tcpDetails.ack = OsCompat.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
             // Switch to NO_QUEUE to prevent illegal socket read/write in repair mode.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_NO_QUEUE);
             // Finally, check if socket is still idle. TODO : this check needs to move to
@@ -198,9 +199,9 @@
             tcpDetails.rcvWndScale = trw.rcvWndScale;
             if (tcpDetails.srcAddress.length == 4 /* V4 address length */) {
                 // Query TOS.
-                tcpDetails.tos = Os.getsockoptInt(fd, IPPROTO_IP, IP_TOS);
+                tcpDetails.tos = OsCompat.getsockoptInt(fd, IPPROTO_IP, IP_TOS);
                 // Query TTL.
-                tcpDetails.ttl = Os.getsockoptInt(fd, IPPROTO_IP, IP_TTL);
+                tcpDetails.ttl = OsCompat.getsockoptInt(fd, IPPROTO_IP, IP_TTL);
             }
         } catch (ErrnoException e) {
             Log.e(TAG, "Exception reading TCP state from socket", e);
@@ -305,7 +306,7 @@
 
     private static boolean isReceiveQueueEmpty(FileDescriptor fd)
             throws ErrnoException {
-        final int result = Os.ioctlInt(fd, SIOCINQ);
+        final int result = OsCompat.ioctlInt(fd, SIOCINQ);
         if (result != 0) {
             Log.e(TAG, "Read queue has data");
             return false;
@@ -315,7 +316,7 @@
 
     private static boolean isSendQueueEmpty(FileDescriptor fd)
             throws ErrnoException {
-        final int result = Os.ioctlInt(fd, SIOCOUTQ);
+        final int result = OsCompat.ioctlInt(fd, SIOCOUTQ);
         if (result != 0) {
             Log.e(TAG, "Write queue has data");
             return false;
diff --git a/tests/integration/src/android/net/TestNetworkStackClient.kt b/tests/integration/src/android/net/TestNetworkStackClient.kt
index 01eb514..61ef5bd 100644
--- a/tests/integration/src/android/net/TestNetworkStackClient.kt
+++ b/tests/integration/src/android/net/TestNetworkStackClient.kt
@@ -19,6 +19,7 @@
 import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
+import android.net.networkstack.NetworkStackClientBase
 import android.os.IBinder
 import com.android.server.net.integrationtests.TestNetworkStackService
 import org.mockito.Mockito.any
@@ -29,28 +30,22 @@
 
 const val TEST_ACTION_SUFFIX = ".Test"
 
-class TestNetworkStackClient(context: Context) : NetworkStackClient(TestDependencies(context)) {
+class TestNetworkStackClient(private val context: Context) : NetworkStackClientBase() {
     // TODO: consider switching to TrackRecord for more expressive checks
     private val lastCallbacks = HashMap<Network, INetworkMonitorCallbacks>()
+    private val moduleConnector = ConnectivityModuleConnector { _, action, _, _ ->
+        val intent = Intent(action)
+        val serviceName = TestNetworkStackService::class.qualifiedName
+                ?: fail("TestNetworkStackService name not found")
+        intent.component = ComponentName(context.packageName, serviceName)
+        return@ConnectivityModuleConnector intent
+    }.also { it.init(context) }
 
-    private class TestDependencies(private val context: Context) : Dependencies {
-        override fun addToServiceManager(service: IBinder) = Unit
-        override fun checkCallerUid() = Unit
-
-        override fun getConnectivityModuleConnector(): ConnectivityModuleConnector {
-            return ConnectivityModuleConnector { _, _, _, inSystemProcess ->
-                getNetworkStackIntent(inSystemProcess)
-            }.also { it.init(context) }
-        }
-
-        private fun getNetworkStackIntent(inSystemProcess: Boolean): Intent? {
-            // Simulate out-of-system-process config: in-process service not found (null intent)
-            if (inSystemProcess) return null
-            val intent = Intent(INetworkStackConnector::class.qualifiedName + TEST_ACTION_SUFFIX)
-            val serviceName = TestNetworkStackService::class.qualifiedName
-                    ?: fail("TestNetworkStackService name not found")
-            intent.component = ComponentName(context.packageName, serviceName)
-            return intent
+    fun start() {
+        moduleConnector.startModuleService(
+                INetworkStackConnector::class.qualifiedName + TEST_ACTION_SUFFIX,
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK) { connector ->
+            onNetworkStackConnected(INetworkStackConnector.Stub.asInterface(connector))
         }
     }
 
diff --git a/tests/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt b/tests/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
index b6e4274..e039ef0 100644
--- a/tests/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
+++ b/tests/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
@@ -157,7 +157,6 @@
         doReturn(IntArray(0)).`when`(systemConfigManager).getSystemPermissionUids(anyString())
 
         networkStackClient = TestNetworkStackClient(realContext)
-        networkStackClient.init()
         networkStackClient.start()
 
         service = TestConnectivityService(makeDependencies())
diff --git a/tests/unit/java/com/android/server/ConnectivityServiceTest.java b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
index 1b4f836..04e63fc 100644
--- a/tests/unit/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
@@ -228,7 +228,6 @@
 import android.net.NetworkScore;
 import android.net.NetworkSpecifier;
 import android.net.NetworkStack;
-import android.net.NetworkStackClient;
 import android.net.NetworkStateSnapshot;
 import android.net.NetworkTestResultParcelable;
 import android.net.OemNetworkPreferences;
@@ -248,6 +247,7 @@
 import android.net.VpnManager;
 import android.net.VpnTransportInfo;
 import android.net.metrics.IpConnectivityLog;
+import android.net.networkstack.NetworkStackClientBase;
 import android.net.resolv.aidl.Nat64PrefixEventParcel;
 import android.net.resolv.aidl.PrivateDnsValidationEventParcel;
 import android.net.shared.NetworkMonitorUtils;
@@ -461,7 +461,7 @@
     @Mock NetworkStatsManager mStatsManager;
     @Mock IDnsResolver mMockDnsResolver;
     @Mock INetd mMockNetd;
-    @Mock NetworkStackClient mNetworkStack;
+    @Mock NetworkStackClientBase mNetworkStack;
     @Mock PackageManager mPackageManager;
     @Mock UserManager mUserManager;
     @Mock NotificationManager mNotificationManager;