diff --git a/core/java/android/net/LinkProperties.java b/core/java/android/net/LinkProperties.java
index aa4b154..06046f7 100644
--- a/core/java/android/net/LinkProperties.java
+++ b/core/java/android/net/LinkProperties.java
@@ -80,8 +80,10 @@
     private final transient boolean mParcelSensitiveFields;
 
     private static final int MIN_MTU    = 68;
-    /* package-visibility - Used in other files (such as Ikev2VpnProfile) as minimum iface MTU. */
-    static final int MIN_MTU_V6 = 1280;
+
+    /** @hide */
+    public static final int MIN_MTU_V6 = 1280;
+
     private static final int MAX_MTU    = 10000;
 
     private static final int INET6_ADDR_LENGTH = 16;
diff --git a/core/java/android/net/NetworkCapabilities.java b/core/java/android/net/NetworkCapabilities.java
index f806b56..40bb8bf 100644
--- a/core/java/android/net/NetworkCapabilities.java
+++ b/core/java/android/net/NetworkCapabilities.java
@@ -339,10 +339,14 @@
     public static final int NET_CAPABILITY_PARTIAL_CONNECTIVITY = 24;
 
     /**
+     * Indicates that this network is temporarily unmetered.
+     * <p>
      * This capability will be set for networks that are generally metered, but are currently
      * unmetered, e.g., because the user is in a particular area. This capability can be changed at
      * any time. When it is removed, applications are responsible for stopping any data transfer
      * that should not occur on a metered network.
+     * Note that most apps should use {@link #NET_CAPABILITY_NOT_METERED} instead. For more
+     * information, see https://developer.android.com/about/versions/11/features/5g#meteredness.
      */
     public static final int NET_CAPABILITY_TEMPORARILY_NOT_METERED = 25;
 
@@ -370,8 +374,8 @@
             | (1 << NET_CAPABILITY_FOREGROUND)
             | (1 << NET_CAPABILITY_NOT_CONGESTED)
             | (1 << NET_CAPABILITY_NOT_SUSPENDED)
-            | (1 << NET_CAPABILITY_PARTIAL_CONNECTIVITY
-            | (1 << NET_CAPABILITY_TEMPORARILY_NOT_METERED));
+            | (1 << NET_CAPABILITY_PARTIAL_CONNECTIVITY)
+            | (1 << NET_CAPABILITY_TEMPORARILY_NOT_METERED);
 
     /**
      * Network capabilities that are not allowed in NetworkRequests. This exists because the
@@ -1802,20 +1806,26 @@
             sb.append(" OwnerUid: ").append(mOwnerUid);
         }
 
-        if (mAdministratorUids.length == 0) {
-            sb.append(" AdministratorUids: ").append(Arrays.toString(mAdministratorUids));
+        if (!ArrayUtils.isEmpty(mAdministratorUids)) {
+            sb.append(" AdminUids: ").append(Arrays.toString(mAdministratorUids));
+        }
+
+        if (mRequestorUid != Process.INVALID_UID) {
+            sb.append(" RequestorUid: ").append(mRequestorUid);
+        }
+
+        if (mRequestorPackageName != null) {
+            sb.append(" RequestorPkg: ").append(mRequestorPackageName);
         }
 
         if (null != mSSID) {
             sb.append(" SSID: ").append(mSSID);
         }
 
-        if (mPrivateDnsBroken) {
-            sb.append(" Private DNS is broken");
-        }
 
-        sb.append(" RequestorUid: ").append(mRequestorUid);
-        sb.append(" RequestorPackageName: ").append(mRequestorPackageName);
+        if (mPrivateDnsBroken) {
+            sb.append(" PrivateDnsBroken");
+        }
 
         sb.append("]");
         return sb.toString();
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index f323cae..655275e 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -5854,7 +5854,6 @@
     @GuardedBy("mBlockedAppUids")
     private final HashSet<Integer> mBlockedAppUids = new HashSet<>();
 
-    // Note: if mDefaultRequest is changed, NetworkMonitor needs to be updated.
     @NonNull
     private final NetworkRequest mDefaultRequest;
     // The NetworkAgentInfo currently satisfying the default request, if any.
diff --git a/services/core/java/com/android/server/connectivity/Nat464Xlat.java b/services/core/java/com/android/server/connectivity/Nat464Xlat.java
index 3091a71..163788f 100644
--- a/services/core/java/com/android/server/connectivity/Nat464Xlat.java
+++ b/services/core/java/com/android/server/connectivity/Nat464Xlat.java
@@ -21,7 +21,7 @@
 import android.net.IDnsResolver;
 import android.net.INetd;
 import android.net.InetAddresses;
-import android.net.InterfaceConfiguration;
+import android.net.InterfaceConfigurationParcel;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
@@ -447,9 +447,10 @@
 
     private LinkAddress getLinkAddress(String iface) {
         try {
-            InterfaceConfiguration config = mNMService.getInterfaceConfig(iface);
-            return config.getLinkAddress();
-        } catch (RemoteException | IllegalStateException e) {
+            final InterfaceConfigurationParcel config = mNetd.interfaceGetCfg(iface);
+            return new LinkAddress(
+                    InetAddresses.parseNumericAddress(config.ipv4Addr), config.prefixLength);
+        } catch (IllegalArgumentException | RemoteException | ServiceSpecificException e) {
             Slog.e(TAG, "Error getting link properties: " + e);
             return null;
         }
diff --git a/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java b/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
index 0563fcd..7f4fb40 100644
--- a/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
+++ b/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
@@ -75,10 +75,11 @@
     private static final boolean DBG = true;
 
     // Notification channels used by ConnectivityService mainline module, it should be aligned with
-    // SystemNotificationChannels.
-    public static final String NOTIFICATION_NETWORK_STATUS = "NETWORK_STATUS";
-    public static final String NOTIFICATION_NETWORK_ALERTS = "NETWORK_ALERTS";
-    public static final String NOTIFICATION_VPN = "VPN";
+    // SystemNotificationChannels so the channels are the same as the ones used as the system
+    // server.
+    public static final String NOTIFICATION_CHANNEL_NETWORK_STATUS = "NETWORK_STATUS";
+    public static final String NOTIFICATION_CHANNEL_NETWORK_ALERTS = "NETWORK_ALERTS";
+    public static final String NOTIFICATION_CHANNEL_VPN = "VPN";
 
     // The context is for the current user (system server)
     private final Context mContext;
@@ -263,7 +264,7 @@
         // the tag.
         final boolean hasPreviousNotification = previousNotifyType != null;
         final String channelId = (highPriority && !hasPreviousNotification)
-                ? NOTIFICATION_NETWORK_ALERTS : NOTIFICATION_NETWORK_STATUS;
+                ? NOTIFICATION_CHANNEL_NETWORK_ALERTS : NOTIFICATION_CHANNEL_NETWORK_STATUS;
         Notification.Builder builder = new Notification.Builder(mContext, channelId)
                 .setWhen(System.currentTimeMillis())
                 .setShowWhen(notifyType == NotificationType.NETWORK_SWITCH)
diff --git a/tests/net/common/java/android/net/MatchAllNetworkSpecifierTest.kt b/tests/net/common/java/android/net/MatchAllNetworkSpecifierTest.kt
index a50f046..a67156a 100644
--- a/tests/net/common/java/android/net/MatchAllNetworkSpecifierTest.kt
+++ b/tests/net/common/java/android/net/MatchAllNetworkSpecifierTest.kt
@@ -19,13 +19,19 @@
 import android.net.wifi.aware.DiscoverySession
 import android.net.wifi.aware.PeerHandle
 import android.net.wifi.aware.WifiAwareNetworkSpecifier
+import android.os.Build
 import androidx.test.filters.SmallTest
 import androidx.test.runner.AndroidJUnit4
 
 import com.android.testutils.assertParcelSane
+import com.android.testutils.DevSdkIgnoreRule
+import com.android.testutils.DevSdkIgnoreRule.IgnoreAfter
+import com.android.testutils.DevSdkIgnoreRule.IgnoreUpTo
 
 import java.lang.IllegalStateException
 
+import org.junit.Assert.assertFalse
+import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.mockito.Mockito
@@ -33,18 +39,32 @@
 @RunWith(AndroidJUnit4::class)
 @SmallTest
 class MatchAllNetworkSpecifierTest {
+    @Rule @JvmField
+    val ignoreRule: DevSdkIgnoreRule = DevSdkIgnoreRule()
+
+    private val specifier = MatchAllNetworkSpecifier()
+    private val discoverySession = Mockito.mock(DiscoverySession::class.java)
+    private val peerHandle = Mockito.mock(PeerHandle::class.java)
+    private val wifiAwareNetworkSpecifier = WifiAwareNetworkSpecifier.Builder(discoverySession,
+            peerHandle).build()
+
     @Test
     fun testParcel() {
         assertParcelSane(MatchAllNetworkSpecifier(), 0)
     }
 
+    @Test @IgnoreAfter(Build.VERSION_CODES.R)
+    fun testCanBeSatisfiedBy_BeforeS() {
+        // MatchAllNetworkSpecifier didn't follow its parent class to change the satisfiedBy() to
+        // canBeSatisfiedBy(), so if a caller calls MatchAllNetworkSpecifier#canBeSatisfiedBy(), the
+        // NetworkSpecifier#canBeSatisfiedBy() will be called actually, and false will be returned.
+        // Although it's not meeting the expectation, the behavior still needs to be verified.
+        assertFalse(specifier.canBeSatisfiedBy(wifiAwareNetworkSpecifier))
+    }
+
     @Test(expected = IllegalStateException::class)
+    @IgnoreUpTo(Build.VERSION_CODES.R)
     fun testCanBeSatisfiedBy() {
-        val specifier = MatchAllNetworkSpecifier()
-        val discoverySession = Mockito.mock(DiscoverySession::class.java)
-        val peerHandle = Mockito.mock(PeerHandle::class.java)
-        val wifiAwareNetworkSpecifier = WifiAwareNetworkSpecifier.Builder(discoverySession,
-                peerHandle).build()
         specifier.canBeSatisfiedBy(wifiAwareNetworkSpecifier)
     }
 }
diff --git a/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt b/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
index dba1856..70f6386 100644
--- a/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
+++ b/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
@@ -200,7 +200,8 @@
         nsInstrumentation.addHttpResponse(HttpResponse(httpProbeUrl, responseCode = 204))
         nsInstrumentation.addHttpResponse(HttpResponse(httpsProbeUrl, responseCode = 204))
 
-        val na = NetworkAgentWrapper(TRANSPORT_CELLULAR, LinkProperties(), context)
+        val na = NetworkAgentWrapper(TRANSPORT_CELLULAR, LinkProperties(), null /* ncTemplate */,
+                context)
         networkStackClient.verifyNetworkMonitorCreated(na.network, TEST_TIMEOUT_MS)
 
         na.addCapability(NET_CAPABILITY_INTERNET)
@@ -238,7 +239,7 @@
 
         val lp = LinkProperties()
         lp.captivePortalApiUrl = Uri.parse(apiUrl)
-        val na = NetworkAgentWrapper(TRANSPORT_CELLULAR, lp, context)
+        val na = NetworkAgentWrapper(TRANSPORT_CELLULAR, lp, null /* ncTemplate */, context)
         networkStackClient.verifyNetworkMonitorCreated(na.network, TEST_TIMEOUT_MS)
 
         na.addCapability(NET_CAPABILITY_INTERNET)
diff --git a/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java b/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
index 85704d0..2a24d1a 100644
--- a/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
+++ b/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
@@ -72,12 +72,12 @@
     private long mKeepaliveResponseDelay = 0L;
     private Integer mExpectedKeepaliveSlot = null;
 
-    public NetworkAgentWrapper(int transport, LinkProperties linkProperties, Context context)
-            throws Exception {
+    public NetworkAgentWrapper(int transport, LinkProperties linkProperties,
+            NetworkCapabilities ncTemplate, Context context) throws Exception {
         final int type = transportToLegacyType(transport);
         final String typeName = ConnectivityManager.getNetworkTypeName(type);
         mNetworkInfo = new NetworkInfo(type, 0, typeName, "Mock");
-        mNetworkCapabilities = new NetworkCapabilities();
+        mNetworkCapabilities = (ncTemplate != null) ? ncTemplate : new NetworkCapabilities();
         mNetworkCapabilities.addCapability(NET_CAPABILITY_NOT_SUSPENDED);
         mNetworkCapabilities.addTransportType(transport);
         switch (transport) {
diff --git a/tests/net/integration/util/com/android/server/TestNetIdManager.kt b/tests/net/integration/util/com/android/server/TestNetIdManager.kt
index eb290dc..938a694 100644
--- a/tests/net/integration/util/com/android/server/TestNetIdManager.kt
+++ b/tests/net/integration/util/com/android/server/TestNetIdManager.kt
@@ -35,4 +35,5 @@
     private val nextId = AtomicInteger(MAX_NET_ID)
     override fun reserveNetId() = nextId.decrementAndGet()
     override fun releaseNetId(id: Int) = Unit
+    fun peekNextNetId() = nextId.get() - 1
 }
diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index 3a46291..6293bef 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -158,7 +158,7 @@
 import android.net.INetworkPolicyManager;
 import android.net.INetworkStatsService;
 import android.net.InetAddresses;
-import android.net.InterfaceConfiguration;
+import android.net.InterfaceConfigurationParcel;
 import android.net.IpPrefix;
 import android.net.IpSecManager;
 import android.net.IpSecManager.UdpEncapsulationSocket;
@@ -322,6 +322,7 @@
     private static final String MOBILE_IFNAME = "test_rmnet_data0";
     private static final String WIFI_IFNAME = "test_wlan0";
     private static final String WIFI_WOL_IFNAME = "test_wlan_wol";
+    private static final String VPN_IFNAME = "tun10042";
     private static final String TEST_PACKAGE_NAME = "com.android.test.package";
     private static final String[] EMPTY_STRING_ARRAY = new String[0];
 
@@ -339,6 +340,7 @@
     private INetworkPolicyListener mPolicyListener;
     private WrappedMultinetworkPolicyTracker mPolicyTracker;
     private HandlerThread mAlarmManagerThread;
+    private TestNetIdManager mNetIdManager;
 
     @Mock IIpConnectivityMetrics mIpConnectivityMetrics;
     @Mock IpConnectivityMetrics.Logger mMetricsService;
@@ -617,12 +619,17 @@
         private String mRedirectUrl;
 
         TestNetworkAgentWrapper(int transport) throws Exception {
-            this(transport, new LinkProperties());
+            this(transport, new LinkProperties(), null);
         }
 
         TestNetworkAgentWrapper(int transport, LinkProperties linkProperties)
                 throws Exception {
-            super(transport, linkProperties, mServiceContext);
+            this(transport, linkProperties, null);
+        }
+
+        private TestNetworkAgentWrapper(int transport, LinkProperties linkProperties,
+                NetworkCapabilities ncTemplate) throws Exception {
+            super(transport, linkProperties, ncTemplate, mServiceContext);
 
             // Waits for the NetworkAgent to be registered, which includes the creation of the
             // NetworkMonitor.
@@ -1017,46 +1024,36 @@
         }
     }
 
+    private Set<UidRange> uidRangesForUid(int uid) {
+        final ArraySet<UidRange> ranges = new ArraySet<>();
+        ranges.add(new UidRange(uid, uid));
+        return ranges;
+    }
+
     private static Looper startHandlerThreadAndReturnLooper() {
         final HandlerThread handlerThread = new HandlerThread("MockVpnThread");
         handlerThread.start();
         return handlerThread.getLooper();
     }
 
-    private class MockVpn extends Vpn {
-        // TODO : the interactions between this mock and the mock network agent are too
-        // hard to get right at this moment, because it's unclear in which case which
-        // target needs to get a method call or both, and in what order. It's because
-        // MockNetworkAgent wants to manage its own NetworkCapabilities, but the Vpn
-        // parent class of MockVpn agent wants that responsibility.
-        // That being said inside the test it should be possible to make the interactions
-        // harder to get wrong with precise speccing, judicious comments, helper methods
-        // and a few sprinkled assertions.
-
-        private boolean mConnected = false;
+    private class MockVpn extends Vpn implements TestableNetworkCallback.HasNetwork {
         // Careful ! This is different from mNetworkAgent, because MockNetworkAgent does
         // not inherit from NetworkAgent.
         private TestNetworkAgentWrapper mMockNetworkAgent;
-        private int mVpnType = VpnManager.TYPE_VPN_SERVICE;
+        private boolean mAgentRegistered = false;
 
+        private int mVpnType = VpnManager.TYPE_VPN_SERVICE;
         private VpnInfo mVpnInfo;
-        private Network[] mUnderlyingNetworks;
 
         public MockVpn(int userId) {
             super(startHandlerThreadAndReturnLooper(), mServiceContext, mNetworkManagementService,
                     userId, mock(KeyStore.class));
-        }
-
-        public void setNetworkAgent(TestNetworkAgentWrapper agent) {
-            agent.waitForIdle(TIMEOUT_MS);
-            mMockNetworkAgent = agent;
-            mNetworkAgent = agent.getNetworkAgent();
-            mNetworkCapabilities.set(agent.getNetworkCapabilities());
+            mConfig = new VpnConfig();
         }
 
         public void setUids(Set<UidRange> uids) {
             mNetworkCapabilities.setUids(uids);
-            updateCapabilities(null /* defaultNetwork */);
+            updateCapabilitiesInternal(null /* defaultNetwork */, true);
         }
 
         public void setVpnType(int vpnType) {
@@ -1064,21 +1061,13 @@
         }
 
         @Override
+        public Network getNetwork() {
+            return (mMockNetworkAgent == null) ? null : mMockNetworkAgent.getNetwork();
+        }
+
+        @Override
         public int getNetId() {
-            if (mMockNetworkAgent == null) {
-                return NETID_UNSET;
-            }
-            return mMockNetworkAgent.getNetwork().netId;
-        }
-
-        @Override
-        public boolean appliesToUid(int uid) {
-            return mConnected;  // Trickery to simplify testing.
-        }
-
-        @Override
-        protected boolean isCallerEstablishedOwnerLocked() {
-            return mConnected;  // Similar trickery
+            return (mMockNetworkAgent == null) ? NETID_UNSET : mMockNetworkAgent.getNetwork().netId;
         }
 
         @Override
@@ -1086,41 +1075,94 @@
             return mVpnType;
         }
 
-        private void connect(boolean isAlwaysMetered) {
-            mNetworkCapabilities.set(mMockNetworkAgent.getNetworkCapabilities());
-            mConnected = true;
-            mConfig = new VpnConfig();
+        private void registerAgent(boolean isAlwaysMetered, Set<UidRange> uids, LinkProperties lp)
+                throws Exception {
+            if (mAgentRegistered) throw new IllegalStateException("already registered");
+            setUids(uids);
             mConfig.isMetered = isAlwaysMetered;
+            mInterface = VPN_IFNAME;
+            mMockNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN, lp,
+                    mNetworkCapabilities);
+            mMockNetworkAgent.waitForIdle(TIMEOUT_MS);
+            mAgentRegistered = true;
+            mNetworkCapabilities.set(mMockNetworkAgent.getNetworkCapabilities());
+            mNetworkAgent = mMockNetworkAgent.getNetworkAgent();
         }
 
-        public void connectAsAlwaysMetered() {
-            connect(true /* isAlwaysMetered */);
+        private void registerAgent(Set<UidRange> uids) throws Exception {
+            registerAgent(false /* isAlwaysMetered */, uids, new LinkProperties());
         }
 
-        public void connect() {
-            connect(false /* isAlwaysMetered */);
+        private void connect(boolean validated, boolean hasInternet, boolean isStrictMode) {
+            mMockNetworkAgent.connect(validated, hasInternet, isStrictMode);
+        }
+
+        private void connect(boolean validated) {
+            mMockNetworkAgent.connect(validated);
+        }
+
+        private TestNetworkAgentWrapper getAgent() {
+            return mMockNetworkAgent;
+        }
+
+        public void establish(LinkProperties lp, int uid, Set<UidRange> ranges, boolean validated,
+                boolean hasInternet, boolean isStrictMode) throws Exception {
+            mNetworkCapabilities.setOwnerUid(uid);
+            mNetworkCapabilities.setAdministratorUids(new int[]{uid});
+            registerAgent(false, ranges, lp);
+            connect(validated, hasInternet, isStrictMode);
+            waitForIdle();
+        }
+
+        public void establish(LinkProperties lp, int uid, Set<UidRange> ranges) throws Exception {
+            establish(lp, uid, ranges, true, true, false);
+        }
+
+        public void establishForMyUid(LinkProperties lp) throws Exception {
+            final int uid = Process.myUid();
+            establish(lp, uid, uidRangesForUid(uid), true, true, false);
+        }
+
+        public void establishForMyUid(boolean validated, boolean hasInternet, boolean isStrictMode)
+                throws Exception {
+            final int uid = Process.myUid();
+            establish(new LinkProperties(), uid, uidRangesForUid(uid), validated, hasInternet,
+                    isStrictMode);
+        }
+
+        public void establishForMyUid() throws Exception {
+            establishForMyUid(new LinkProperties());
+        }
+
+        public void sendLinkProperties(LinkProperties lp) {
+            mMockNetworkAgent.sendLinkProperties(lp);
+        }
+
+        private NetworkCapabilities updateCapabilitiesInternal(Network defaultNetwork,
+                boolean sendToConnectivityService) {
+            if (!mAgentRegistered) return null;
+            super.updateCapabilities(defaultNetwork);
+            // Because super.updateCapabilities will update the capabilities of the agent but
+            // not the mock agent, the mock agent needs to know about them.
+            copyCapabilitiesToNetworkAgent(sendToConnectivityService);
+            return new NetworkCapabilities(mNetworkCapabilities);
+        }
+
+        private void copyCapabilitiesToNetworkAgent(boolean sendToConnectivityService) {
+            if (null != mMockNetworkAgent) {
+                mMockNetworkAgent.setNetworkCapabilities(mNetworkCapabilities,
+                        sendToConnectivityService);
+            }
         }
 
         @Override
         public NetworkCapabilities updateCapabilities(Network defaultNetwork) {
-            if (!mConnected) return null;
-            super.updateCapabilities(defaultNetwork);
-            // Because super.updateCapabilities will update the capabilities of the agent but
-            // not the mock agent, the mock agent needs to know about them.
-            copyCapabilitiesToNetworkAgent();
-            return new NetworkCapabilities(mNetworkCapabilities);
-        }
-
-        private void copyCapabilitiesToNetworkAgent() {
-            if (null != mMockNetworkAgent) {
-                mMockNetworkAgent.setNetworkCapabilities(mNetworkCapabilities,
-                        false /* sendToConnectivityService */);
-            }
+            return updateCapabilitiesInternal(defaultNetwork, false);
         }
 
         public void disconnect() {
-            mConnected = false;
-            mConfig = null;
+            if (mMockNetworkAgent != null) mMockNetworkAgent.disconnect();
+            mAgentRegistered = false;
         }
 
         @Override
@@ -1133,18 +1175,6 @@
         private synchronized void setVpnInfo(VpnInfo vpnInfo) {
             mVpnInfo = vpnInfo;
         }
-
-        @Override
-        public synchronized Network[] getUnderlyingNetworks() {
-            if (mUnderlyingNetworks != null) return mUnderlyingNetworks;
-
-            return super.getUnderlyingNetworks();
-        }
-
-        /** Don't override behavior for {@link Vpn#setUnderlyingNetworks}. */
-        private synchronized void overrideUnderlyingNetworks(Network[] underlyingNetworks) {
-            mUnderlyingNetworks = underlyingNetworks;
-        }
     }
 
     private void mockVpn(int uid) {
@@ -1207,6 +1237,8 @@
 
     @Before
     public void setUp() throws Exception {
+        mNetIdManager = new TestNetIdManager();
+
         mContext = InstrumentationRegistry.getContext();
 
         MockitoAnnotations.initMocks(this);
@@ -1277,7 +1309,7 @@
         doNothing().when(mSystemProperties).setTcpInitRwnd(anyInt());
         final ConnectivityService.Dependencies deps = mock(ConnectivityService.Dependencies.class);
         doReturn(mCsHandlerThread).when(deps).makeHandlerThread();
-        doReturn(new TestNetIdManager()).when(deps).makeNetIdManager();
+        doReturn(mNetIdManager).when(deps).makeNetIdManager();
         doReturn(mNetworkStack).when(deps).getNetworkStack();
         doReturn(mSystemProperties).when(deps).getSystemProperties();
         doReturn(mock(ProxyTracker.class)).when(deps).makeProxyTracker(any(), any());
@@ -1335,6 +1367,9 @@
             mEthernetNetworkAgent.disconnect();
             mEthernetNetworkAgent = null;
         }
+        mMockVpn.disconnect();
+        waitForIdle();
+
         FakeSettingsProvider.clearSettingsProvider();
 
         mCsHandlerThread.quitSafely();
@@ -3218,20 +3253,12 @@
         waitForIdle();
         assertEquals(null, mCm.getActiveNetwork());
 
-        final int uid = Process.myUid();
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true);
-        mMockVpn.connect();
-        defaultNetworkCallback.expectAvailableThenValidatedCallbacks(vpnNetworkAgent);
+        mMockVpn.establishForMyUid();
+        defaultNetworkCallback.expectAvailableThenValidatedCallbacks(mMockVpn);
         assertEquals(defaultNetworkCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        vpnNetworkAgent.disconnect();
-        defaultNetworkCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        mMockVpn.disconnect();
+        defaultNetworkCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
         waitForIdle();
         assertEquals(null, mCm.getActiveNetwork());
     }
@@ -4808,13 +4835,52 @@
         mCm.unregisterNetworkCallback(networkCallback);
     }
 
+    private <T> void assertSameElementsNoDuplicates(T[] expected, T[] actual) {
+        // Easier to implement than a proper "assertSameElements" method that also correctly deals
+        // with duplicates.
+        final String msg = Arrays.toString(expected) + " != " + Arrays.toString(actual);
+        assertEquals(msg, expected.length, actual.length);
+        Set expectedSet = new ArraySet<>(Arrays.asList(expected));
+        assertEquals("expected contains duplicates", expectedSet.size(), expected.length);
+        // actual cannot have duplicates because it's the same length and has the same elements.
+        Set actualSet = new ArraySet<>(Arrays.asList(actual));
+        assertEquals(expectedSet, actualSet);
+    }
+
+    private void expectForceUpdateIfaces(Network[] networks, String defaultIface,
+            Integer vpnUid, String vpnIfname, String[] underlyingIfaces) throws Exception {
+        ArgumentCaptor<Network[]> networksCaptor = ArgumentCaptor.forClass(Network[].class);
+        ArgumentCaptor<VpnInfo[]> vpnInfosCaptor = ArgumentCaptor.forClass(VpnInfo[].class);
+
+        verify(mStatsService, atLeastOnce()).forceUpdateIfaces(networksCaptor.capture(),
+                any(NetworkState[].class), eq(defaultIface), vpnInfosCaptor.capture());
+
+        assertSameElementsNoDuplicates(networksCaptor.getValue(), networks);
+
+        VpnInfo[] infos = vpnInfosCaptor.getValue();
+        if (vpnUid != null) {
+            assertEquals("Should have exactly one VPN:", 1, infos.length);
+            VpnInfo info = infos[0];
+            assertEquals("Unexpected VPN owner:", (int) vpnUid, info.ownerUid);
+            assertEquals("Unexpected VPN interface:", vpnIfname, info.vpnIface);
+            assertSameElementsNoDuplicates(underlyingIfaces, info.underlyingIfaces);
+        } else {
+            assertEquals(0, infos.length);
+            return;
+        }
+    }
+
+    private void expectForceUpdateIfaces(Network[] networks, String defaultIface) throws Exception {
+        expectForceUpdateIfaces(networks, defaultIface, null, null, new String[0]);
+    }
+
     @Test
     public void testStatsIfacesChanged() throws Exception {
         mCellNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_CELLULAR);
         mWiFiNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_WIFI);
 
-        Network[] onlyCell = new Network[] {mCellNetworkAgent.getNetwork()};
-        Network[] onlyWifi = new Network[] {mWiFiNetworkAgent.getNetwork()};
+        final Network[] onlyCell = new Network[] {mCellNetworkAgent.getNetwork()};
+        final Network[] onlyWifi = new Network[] {mWiFiNetworkAgent.getNetwork()};
 
         LinkProperties cellLp = new LinkProperties();
         cellLp.setInterfaceName(MOBILE_IFNAME);
@@ -4825,9 +4891,7 @@
         mCellNetworkAgent.connect(false);
         mCellNetworkAgent.sendLinkProperties(cellLp);
         waitForIdle();
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyCell), any(NetworkState[].class), eq(MOBILE_IFNAME),
-                        eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyCell, MOBILE_IFNAME);
         reset(mStatsService);
 
         // Default network switch should update ifaces.
@@ -4835,32 +4899,24 @@
         mWiFiNetworkAgent.sendLinkProperties(wifiLp);
         waitForIdle();
         assertEquals(wifiLp, mService.getActiveLinkProperties());
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyWifi), any(NetworkState[].class), eq(WIFI_IFNAME),
-                        eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyWifi, WIFI_IFNAME);
         reset(mStatsService);
 
         // Disconnect should update ifaces.
         mWiFiNetworkAgent.disconnect();
         waitForIdle();
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyCell), any(NetworkState[].class),
-                        eq(MOBILE_IFNAME), eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyCell, MOBILE_IFNAME);
         reset(mStatsService);
 
         // Metered change should update ifaces
         mCellNetworkAgent.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED);
         waitForIdle();
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyCell), any(NetworkState[].class), eq(MOBILE_IFNAME),
-                        eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyCell, MOBILE_IFNAME);
         reset(mStatsService);
 
         mCellNetworkAgent.removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED);
         waitForIdle();
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyCell), any(NetworkState[].class), eq(MOBILE_IFNAME),
-                        eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyCell, MOBILE_IFNAME);
         reset(mStatsService);
 
         // Captive portal change shouldn't update ifaces
@@ -4874,9 +4930,102 @@
         // Roaming change should update ifaces
         mCellNetworkAgent.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING);
         waitForIdle();
-        verify(mStatsService, atLeastOnce())
-                .forceUpdateIfaces(eq(onlyCell), any(NetworkState[].class), eq(MOBILE_IFNAME),
-                        eq(new VpnInfo[0]));
+        expectForceUpdateIfaces(onlyCell, MOBILE_IFNAME);
+        reset(mStatsService);
+
+        // Test VPNs.
+        final LinkProperties lp = new LinkProperties();
+        lp.setInterfaceName(VPN_IFNAME);
+
+        mMockVpn.establishForMyUid(lp);
+
+        final Network[] cellAndVpn = new Network[] {
+                mCellNetworkAgent.getNetwork(), mMockVpn.getNetwork()};
+        Network[] cellAndWifi = new Network[] {
+                mCellNetworkAgent.getNetwork(), mWiFiNetworkAgent.getNetwork()};
+
+        // A VPN with default (null) underlying networks sets the underlying network's interfaces...
+        expectForceUpdateIfaces(cellAndVpn, MOBILE_IFNAME, Process.myUid(), VPN_IFNAME,
+                new String[]{MOBILE_IFNAME});
+
+        // ...and updates them as the default network switches.
+        mWiFiNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_WIFI);
+        mWiFiNetworkAgent.connect(false);
+        mWiFiNetworkAgent.sendLinkProperties(wifiLp);
+        final Network[] wifiAndVpn = new Network[] {
+                mWiFiNetworkAgent.getNetwork(), mMockVpn.getNetwork()};
+        cellAndWifi = new Network[] {
+                mCellNetworkAgent.getNetwork(), mWiFiNetworkAgent.getNetwork()};
+
+        waitForIdle();
+        assertEquals(wifiLp, mService.getActiveLinkProperties());
+        expectForceUpdateIfaces(wifiAndVpn, WIFI_IFNAME, Process.myUid(), VPN_IFNAME,
+                new String[]{WIFI_IFNAME});
+        reset(mStatsService);
+
+        // A VPN that sets its underlying networks passes the underlying interfaces, and influences
+        // the default interface sent to NetworkStatsService by virtue of applying to the system
+        // server UID (or, in this test, to the test's UID). This is the reason for sending
+        // MOBILE_IFNAME even though the default network is wifi.
+        // TODO: fix this to pass in the actual default network interface. Whether or not the VPN
+        // applies to the system server UID should not have any bearing on network stats.
+        mService.setUnderlyingNetworksForVpn(onlyCell);
+        waitForIdle();
+        expectForceUpdateIfaces(wifiAndVpn, MOBILE_IFNAME, Process.myUid(), VPN_IFNAME,
+                new String[]{MOBILE_IFNAME});
+        reset(mStatsService);
+
+        mService.setUnderlyingNetworksForVpn(cellAndWifi);
+        waitForIdle();
+        expectForceUpdateIfaces(wifiAndVpn, MOBILE_IFNAME, Process.myUid(), VPN_IFNAME,
+                new String[]{MOBILE_IFNAME, WIFI_IFNAME});
+        reset(mStatsService);
+
+        // If an underlying network disconnects, that interface should no longer be underlying.
+        // This doesn't actually work because disconnectAndDestroyNetwork only notifies
+        // NetworkStatsService before the underlying network is actually removed. So the underlying
+        // network will only be removed if notifyIfacesChangedForNetworkStats is called again. This
+        // could result in incorrect data usage measurements if the interface used by the
+        // disconnected network is reused by a system component that does not register an agent for
+        // it (e.g., tethering).
+        mCellNetworkAgent.disconnect();
+        waitForIdle();
+        assertNull(mService.getLinkProperties(mCellNetworkAgent.getNetwork()));
+        expectForceUpdateIfaces(wifiAndVpn, MOBILE_IFNAME, Process.myUid(), VPN_IFNAME,
+                new String[]{MOBILE_IFNAME, WIFI_IFNAME});
+
+        // Confirm that we never tell NetworkStatsService that cell is no longer the underlying
+        // network for the VPN...
+        verify(mStatsService, never()).forceUpdateIfaces(any(Network[].class),
+                any(NetworkState[].class), any() /* anyString() doesn't match null */,
+                argThat(infos -> infos[0].underlyingIfaces.length == 1
+                        && WIFI_IFNAME.equals(infos[0].underlyingIfaces[0])));
+        verifyNoMoreInteractions(mStatsService);
+        reset(mStatsService);
+
+        // ... but if something else happens that causes notifyIfacesChangedForNetworkStats to be
+        // called again, it does. For example, connect Ethernet, but with a low score, such that it
+        // does not become the default network.
+        mEthernetNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_ETHERNET);
+        mEthernetNetworkAgent.adjustScore(-40);
+        mEthernetNetworkAgent.connect(false);
+        waitForIdle();
+        verify(mStatsService).forceUpdateIfaces(any(Network[].class),
+                any(NetworkState[].class), any() /* anyString() doesn't match null */,
+                argThat(vpnInfos -> vpnInfos[0].underlyingIfaces.length == 1
+                        && WIFI_IFNAME.equals(vpnInfos[0].underlyingIfaces[0])));
+        mEthernetNetworkAgent.disconnect();
+        reset(mStatsService);
+
+        // When a VPN declares no underlying networks (i.e., no connectivity), getAllVpnInfo
+        // does not return the VPN, so CS does not pass it to NetworkStatsService. This causes
+        // NetworkStatsFactory#adjustForTunAnd464Xlat not to attempt any VPN data migration, which
+        // is probably a performance improvement (though it's very unlikely that a VPN would declare
+        // no underlying networks).
+        // Also, for the same reason as above, the active interface passed in is null.
+        mService.setUnderlyingNetworksForVpn(new Network[0]);
+        waitForIdle();
+        expectForceUpdateIfaces(wifiAndVpn, null);
         reset(mStatsService);
     }
 
@@ -5232,6 +5381,58 @@
     }
 
     @Test
+    public void testVpnConnectDisconnectUnderlyingNetwork() throws Exception {
+        final TestNetworkCallback callback = new TestNetworkCallback();
+        final NetworkRequest request = new NetworkRequest.Builder()
+                .removeCapability(NET_CAPABILITY_NOT_VPN).build();
+
+        mCm.registerNetworkCallback(request, callback);
+
+        // Bring up a VPN that specifies an underlying network that does not exist yet.
+        // Note: it's sort of meaningless for a VPN app to declare a network that doesn't exist yet,
+        // (and doing so is difficult without using reflection) but it's good to test that the code
+        // behaves approximately correctly.
+        mMockVpn.establishForMyUid(false, true, false);
+        final Network wifiNetwork = new Network(mNetIdManager.peekNextNetId());
+        mService.setUnderlyingNetworksForVpn(new Network[]{wifiNetwork});
+        callback.expectAvailableCallbacksUnvalidated(mMockVpn);
+        assertTrue(mCm.getNetworkCapabilities(mMockVpn.getNetwork())
+                .hasTransport(TRANSPORT_VPN));
+        assertFalse(mCm.getNetworkCapabilities(mMockVpn.getNetwork())
+                .hasTransport(TRANSPORT_WIFI));
+
+        // Make that underlying network connect, and expect to see its capabilities immediately
+        // reflected in the VPN's capabilities.
+        mWiFiNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_WIFI);
+        assertEquals(wifiNetwork, mWiFiNetworkAgent.getNetwork());
+        mWiFiNetworkAgent.connect(false);
+        // TODO: the callback for the VPN happens before any callbacks are called for the wifi
+        // network that has just connected. There appear to be two issues here:
+        // 1. The VPN code will accept an underlying network as soon as getNetworkCapabilities() for
+        //    it returns non-null (which happens very early, during handleRegisterNetworkAgent).
+        //    This is not correct because that that point the network is not connected and cannot
+        //    pass any traffic.
+        // 2. When a network connects, updateNetworkInfo propagates underlying network capabilities
+        //    before rematching networks.
+        // Given that this scenario can't really happen, this is probably fine for now.
+        callback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, mMockVpn);
+        callback.expectAvailableCallbacksUnvalidated(mWiFiNetworkAgent);
+        assertTrue(mCm.getNetworkCapabilities(mMockVpn.getNetwork())
+                .hasTransport(TRANSPORT_VPN));
+        assertTrue(mCm.getNetworkCapabilities(mMockVpn.getNetwork())
+                .hasTransport(TRANSPORT_WIFI));
+
+        // Disconnect the network, and expect to see the VPN capabilities change accordingly.
+        mWiFiNetworkAgent.disconnect();
+        callback.expectCallback(CallbackEntry.LOST, mWiFiNetworkAgent);
+        callback.expectCapabilitiesThat(mMockVpn, (nc) ->
+                nc.getTransportTypes().length == 1 && nc.hasTransport(TRANSPORT_VPN));
+
+        mMockVpn.disconnect();
+        mCm.unregisterNetworkCallback(callback);
+    }
+
+    @Test
     public void testVpnNetworkActive() throws Exception {
         final int uid = Process.myUid();
 
@@ -5265,42 +5466,38 @@
         vpnNetworkCallback.assertNoCallback();
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
+        final Set<UidRange> ranges = uidRangesForUid(uid);
+        mMockVpn.registerAgent(ranges);
+
         // VPN networks do not satisfy the default request and are automatically validated
         // by NetworkMonitor
         assertFalse(NetworkMonitorUtils.isValidationRequired(
-                vpnNetworkAgent.getNetworkCapabilities()));
-        vpnNetworkAgent.setNetworkValid(false /* isStrictMode */);
+                mMockVpn.getAgent().getNetworkCapabilities()));
+        mMockVpn.getAgent().setNetworkValid(false /* isStrictMode */);
 
-        vpnNetworkAgent.connect(false);
-        mMockVpn.connect();
-        mMockVpn.setUnderlyingNetworks(new Network[0]);
+        mMockVpn.connect(false);
+        mService.setUnderlyingNetworksForVpn(new Network[0]);
 
-        genericNetworkCallback.expectAvailableCallbacksUnvalidated(vpnNetworkAgent);
+        genericNetworkCallback.expectAvailableCallbacksUnvalidated(mMockVpn);
         genericNotVpnNetworkCallback.assertNoCallback();
         wifiNetworkCallback.assertNoCallback();
-        vpnNetworkCallback.expectAvailableCallbacksUnvalidated(vpnNetworkAgent);
-        defaultCallback.expectAvailableCallbacksUnvalidated(vpnNetworkAgent);
+        vpnNetworkCallback.expectAvailableCallbacksUnvalidated(mMockVpn);
+        defaultCallback.expectAvailableCallbacksUnvalidated(mMockVpn);
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        genericNetworkCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, vpnNetworkAgent);
+        genericNetworkCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, mMockVpn);
         genericNotVpnNetworkCallback.assertNoCallback();
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent, nc -> null == nc.getUids());
-        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, vpnNetworkAgent);
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn, nc -> null == nc.getUids());
+        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, mMockVpn);
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
         ranges.clear();
-        vpnNetworkAgent.setUids(ranges);
+        mMockVpn.setUids(ranges);
 
-        genericNetworkCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        genericNetworkCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
         genericNotVpnNetworkCallback.assertNoCallback();
         wifiNetworkCallback.assertNoCallback();
-        vpnNetworkCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        vpnNetworkCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
 
         // TODO : The default network callback should actually get a LOST call here (also see the
         // comment below for AVAILABLE). This is because ConnectivityService does not look at UID
@@ -5308,19 +5505,18 @@
         // can't currently update their UIDs without disconnecting, so this does not matter too
         // much, but that is the reason the test here has to check for an update to the
         // capabilities instead of the expected LOST then AVAILABLE.
-        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, vpnNetworkAgent);
+        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, mMockVpn);
 
         ranges.add(new UidRange(uid, uid));
         mMockVpn.setUids(ranges);
-        vpnNetworkAgent.setUids(ranges);
 
-        genericNetworkCallback.expectAvailableCallbacksValidated(vpnNetworkAgent);
+        genericNetworkCallback.expectAvailableCallbacksValidated(mMockVpn);
         genericNotVpnNetworkCallback.assertNoCallback();
         wifiNetworkCallback.assertNoCallback();
-        vpnNetworkCallback.expectAvailableCallbacksValidated(vpnNetworkAgent);
+        vpnNetworkCallback.expectAvailableCallbacksValidated(mMockVpn);
         // TODO : Here like above, AVAILABLE would be correct, but because this can't actually
         // happen outside of the test, ConnectivityService does not rematch callbacks.
-        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, vpnNetworkAgent);
+        defaultCallback.expectCallback(CallbackEntry.NETWORK_CAPS_UPDATED, mMockVpn);
 
         mWiFiNetworkAgent.disconnect();
 
@@ -5330,13 +5526,13 @@
         vpnNetworkCallback.assertNoCallback();
         defaultCallback.assertNoCallback();
 
-        vpnNetworkAgent.disconnect();
+        mMockVpn.disconnect();
 
-        genericNetworkCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        genericNetworkCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
         genericNotVpnNetworkCallback.assertNoCallback();
         wifiNetworkCallback.assertNoCallback();
-        vpnNetworkCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
-        defaultCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        vpnNetworkCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
+        defaultCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
         assertEquals(null, mCm.getActiveNetwork());
 
         mCm.unregisterNetworkCallback(genericNetworkCallback);
@@ -5358,20 +5554,13 @@
         defaultCallback.expectAvailableThenValidatedCallbacks(mWiFiNetworkAgent);
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true /* validated */, false /* hasInternet */,
+        mMockVpn.establishForMyUid(true /* validated */, false /* hasInternet */,
                 false /* isStrictMode */);
-        mMockVpn.connect();
 
         defaultCallback.assertNoCallback();
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        vpnNetworkAgent.disconnect();
+        mMockVpn.disconnect();
         defaultCallback.assertNoCallback();
 
         mCm.unregisterNetworkCallback(defaultCallback);
@@ -5390,21 +5579,14 @@
         defaultCallback.expectAvailableThenValidatedCallbacks(mWiFiNetworkAgent);
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true /* validated */, true /* hasInternet */,
+        mMockVpn.establishForMyUid(true /* validated */, true /* hasInternet */,
                 false /* isStrictMode */);
-        mMockVpn.connect();
 
-        defaultCallback.expectAvailableThenValidatedCallbacks(vpnNetworkAgent);
+        defaultCallback.expectAvailableThenValidatedCallbacks(mMockVpn);
         assertEquals(defaultCallback.getLastAvailableNetwork(), mCm.getActiveNetwork());
 
-        vpnNetworkAgent.disconnect();
-        defaultCallback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        mMockVpn.disconnect();
+        defaultCallback.expectCallback(CallbackEntry.LOST, mMockVpn);
         defaultCallback.expectAvailableCallbacksValidated(mWiFiNetworkAgent);
 
         mCm.unregisterNetworkCallback(defaultCallback);
@@ -5422,44 +5604,36 @@
         callback.assertNoCallback();
 
         // Bring up a VPN that has the INTERNET capability, initially unvalidated.
-        final int uid = Process.myUid();
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(false /* validated */, true /* hasInternet */,
+        mMockVpn.establishForMyUid(false /* validated */, true /* hasInternet */,
                 false /* isStrictMode */);
-        mMockVpn.connect();
 
         // Even though the VPN is unvalidated, it becomes the default network for our app.
-        callback.expectAvailableCallbacksUnvalidated(vpnNetworkAgent);
+        callback.expectAvailableCallbacksUnvalidated(mMockVpn);
         callback.assertNoCallback();
 
-        assertTrue(vpnNetworkAgent.getScore() > mEthernetNetworkAgent.getScore());
-        assertEquals(ConnectivityConstants.VPN_DEFAULT_SCORE, vpnNetworkAgent.getScore());
-        assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork());
+        assertTrue(mMockVpn.getAgent().getScore() > mEthernetNetworkAgent.getScore());
+        assertEquals(ConnectivityConstants.VPN_DEFAULT_SCORE, mMockVpn.getAgent().getScore());
+        assertEquals(mMockVpn.getNetwork(), mCm.getActiveNetwork());
 
-        NetworkCapabilities nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork());
+        NetworkCapabilities nc = mCm.getNetworkCapabilities(mMockVpn.getNetwork());
         assertFalse(nc.hasCapability(NET_CAPABILITY_VALIDATED));
         assertTrue(nc.hasCapability(NET_CAPABILITY_INTERNET));
 
         assertFalse(NetworkMonitorUtils.isValidationRequired(
-                vpnNetworkAgent.getNetworkCapabilities()));
+                mMockVpn.getAgent().getNetworkCapabilities()));
         assertTrue(NetworkMonitorUtils.isPrivateDnsValidationRequired(
-                vpnNetworkAgent.getNetworkCapabilities()));
+                mMockVpn.getAgent().getNetworkCapabilities()));
 
         // Pretend that the VPN network validates.
-        vpnNetworkAgent.setNetworkValid(false /* isStrictMode */);
-        vpnNetworkAgent.mNetworkMonitor.forceReevaluation(Process.myUid());
+        mMockVpn.getAgent().setNetworkValid(false /* isStrictMode */);
+        mMockVpn.getAgent().mNetworkMonitor.forceReevaluation(Process.myUid());
         // Expect to see the validated capability, but no other changes, because the VPN is already
         // the default network for the app.
-        callback.expectCapabilitiesWith(NET_CAPABILITY_VALIDATED, vpnNetworkAgent);
+        callback.expectCapabilitiesWith(NET_CAPABILITY_VALIDATED, mMockVpn);
         callback.assertNoCallback();
 
-        vpnNetworkAgent.disconnect();
-        callback.expectCallback(CallbackEntry.LOST, vpnNetworkAgent);
+        mMockVpn.disconnect();
+        callback.expectCallback(CallbackEntry.LOST, mMockVpn);
         callback.expectAvailableCallbacksValidated(mEthernetNetworkAgent);
     }
 
@@ -5481,21 +5655,15 @@
         mCellNetworkAgent.addCapability(NET_CAPABILITY_NOT_SUSPENDED);
         mCellNetworkAgent.connect(true);
 
-        final TestNetworkAgentWrapper vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.connect();
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true /* validated */, false /* hasInternet */,
+        mMockVpn.establishForMyUid(true /* validated */, false /* hasInternet */,
                 false /* isStrictMode */);
 
-        vpnNetworkCallback.expectAvailableCallbacks(vpnNetworkAgent.getNetwork(),
+        vpnNetworkCallback.expectAvailableCallbacks(mMockVpn.getNetwork(),
                 false /* suspended */, false /* validated */, false /* blocked */, TIMEOUT_MS);
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent.getNetwork(), TIMEOUT_MS,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn.getNetwork(), TIMEOUT_MS,
                 nc -> nc.hasCapability(NET_CAPABILITY_VALIDATED));
 
-        final NetworkCapabilities nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork());
+        final NetworkCapabilities nc = mCm.getNetworkCapabilities(mMockVpn.getNetwork());
         assertTrue(nc.hasTransport(TRANSPORT_VPN));
         assertTrue(nc.hasTransport(TRANSPORT_CELLULAR));
         assertFalse(nc.hasTransport(TRANSPORT_WIFI));
@@ -5517,18 +5685,11 @@
         mCm.registerNetworkCallback(vpnNetworkRequest, vpnNetworkCallback);
         vpnNetworkCallback.assertNoCallback();
 
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.connect();
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true /* validated */, false /* hasInternet */,
+        mMockVpn.establishForMyUid(true /* validated */, false /* hasInternet */,
                 false /* isStrictMode */);
 
-        vpnNetworkCallback.expectAvailableThenValidatedCallbacks(vpnNetworkAgent);
-        nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork());
+        vpnNetworkCallback.expectAvailableThenValidatedCallbacks(mMockVpn);
+        nc = mCm.getNetworkCapabilities(mMockVpn.getNetwork());
         assertTrue(nc.hasTransport(TRANSPORT_VPN));
         assertFalse(nc.hasTransport(TRANSPORT_CELLULAR));
         assertFalse(nc.hasTransport(TRANSPORT_WIFI));
@@ -5545,7 +5706,7 @@
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5559,7 +5720,7 @@
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork(), mWiFiNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5569,7 +5730,7 @@
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5577,27 +5738,27 @@
 
         // Remove NOT_SUSPENDED from the only network and observe VPN is now suspended.
         mCellNetworkAgent.removeCapability(NET_CAPABILITY_NOT_SUSPENDED);
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_SUSPENDED));
-        vpnNetworkCallback.expectCallback(CallbackEntry.SUSPENDED, vpnNetworkAgent);
+        vpnNetworkCallback.expectCallback(CallbackEntry.SUSPENDED, mMockVpn);
 
         // Add NOT_SUSPENDED again and observe VPN is no longer suspended.
         mCellNetworkAgent.addCapability(NET_CAPABILITY_NOT_SUSPENDED);
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
                 && caps.hasCapability(NET_CAPABILITY_NOT_SUSPENDED));
-        vpnNetworkCallback.expectCallback(CallbackEntry.RESUMED, vpnNetworkAgent);
+        vpnNetworkCallback.expectCallback(CallbackEntry.RESUMED, mMockVpn);
 
         // Use Wifi but not cell. Note the VPN is now unmetered and not suspended.
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mWiFiNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5607,7 +5768,7 @@
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork(), mWiFiNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5620,7 +5781,7 @@
         // Stop using WiFi. The VPN is suspended again.
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork() });
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5634,7 +5795,7 @@
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork(), mWiFiNetworkAgent.getNetwork() });
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED)
@@ -5645,14 +5806,14 @@
         // Disconnect cell. Receive update without even removing the dead network from the
         // underlying networks – it's dead anyway. Not metered any more.
         mCellNetworkAgent.disconnect();
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && caps.hasCapability(NET_CAPABILITY_NOT_METERED));
 
         // Disconnect wifi too. No underlying networks means this is now metered.
         mWiFiNetworkAgent.disconnect();
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED));
@@ -5673,18 +5834,11 @@
         mCm.registerNetworkCallback(vpnNetworkRequest, vpnNetworkCallback);
         vpnNetworkCallback.assertNoCallback();
 
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.connect();
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true /* validated */, false /* hasInternet */,
+        mMockVpn.establishForMyUid(true /* validated */, false /* hasInternet */,
                 false /* isStrictMode */);
 
-        vpnNetworkCallback.expectAvailableThenValidatedCallbacks(vpnNetworkAgent);
-        nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork());
+        vpnNetworkCallback.expectAvailableThenValidatedCallbacks(mMockVpn);
+        nc = mCm.getNetworkCapabilities(mMockVpn.getNetwork());
         assertTrue(nc.hasTransport(TRANSPORT_VPN));
         assertFalse(nc.hasTransport(TRANSPORT_CELLULAR));
         assertFalse(nc.hasTransport(TRANSPORT_WIFI));
@@ -5696,7 +5850,7 @@
         mCellNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_CELLULAR);
         mCellNetworkAgent.connect(true);
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED));
@@ -5706,7 +5860,7 @@
         mWiFiNetworkAgent.addCapability(NET_CAPABILITY_NOT_METERED);
         mWiFiNetworkAgent.connect(true);
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && caps.hasTransport(TRANSPORT_WIFI)
                 && caps.hasCapability(NET_CAPABILITY_NOT_METERED));
@@ -5718,7 +5872,7 @@
         // Disconnect wifi too. Now we have no default network.
         mWiFiNetworkAgent.disconnect();
 
-        vpnNetworkCallback.expectCapabilitiesThat(vpnNetworkAgent,
+        vpnNetworkCallback.expectCapabilitiesThat(mMockVpn,
                 (caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
                 && !caps.hasCapability(NET_CAPABILITY_NOT_METERED));
@@ -5761,18 +5915,10 @@
         assertTrue(mCm.isActiveNetworkMetered());
 
         // Connect VPN network. By default it is using current default network (Cell).
-        TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        final int uid = Process.myUid();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true);
-        mMockVpn.connect();
-        waitForIdle();
+        mMockVpn.establishForMyUid();
+
         // Ensure VPN is now the active network.
-        assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork());
+        assertEquals(mMockVpn.getNetwork(), mCm.getActiveNetwork());
 
         // Expect VPN to be metered.
         assertTrue(mCm.isActiveNetworkMetered());
@@ -5783,7 +5929,7 @@
         mWiFiNetworkAgent.connect(true);
         waitForIdle();
         // VPN should still be the active network.
-        assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork());
+        assertEquals(mMockVpn.getNetwork(), mCm.getActiveNetwork());
 
         // Expect VPN to be unmetered as it should now be using WiFi (new default).
         assertFalse(mCm.isActiveNetworkMetered());
@@ -5801,7 +5947,6 @@
         // VPN without any underlying networks is treated as metered.
         assertTrue(mCm.isActiveNetworkMetered());
 
-        vpnNetworkAgent.disconnect();
         mMockVpn.disconnect();
     }
 
@@ -5822,18 +5967,10 @@
         assertFalse(mCm.isActiveNetworkMetered());
 
         // Connect VPN network.
-        TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        final int uid = Process.myUid();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true);
-        mMockVpn.connect();
-        waitForIdle();
+        mMockVpn.establishForMyUid();
+
         // Ensure VPN is now the active network.
-        assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork());
+        assertEquals(mMockVpn.getNetwork(), mCm.getActiveNetwork());
         // VPN is using Cell
         mService.setUnderlyingNetworksForVpn(
                 new Network[] { mCellNetworkAgent.getNetwork() });
@@ -5873,7 +6010,6 @@
         // VPN without underlying networks is treated as metered.
         assertTrue(mCm.isActiveNetworkMetered());
 
-        vpnNetworkAgent.disconnect();
         mMockVpn.disconnect();
     }
 
@@ -5888,17 +6024,11 @@
         assertFalse(mCm.isActiveNetworkMetered());
 
         // Connect VPN network.
-        TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        final int uid = Process.myUid();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.setUids(ranges);
-        vpnNetworkAgent.connect(true);
-        mMockVpn.connectAsAlwaysMetered();
+        mMockVpn.registerAgent(true /* isAlwaysMetered */, uidRangesForUid(Process.myUid()),
+                new LinkProperties());
+        mMockVpn.connect(true);
         waitForIdle();
-        assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork());
+        assertEquals(mMockVpn.getNetwork(), mCm.getActiveNetwork());
 
         // VPN is tracking current platform default (WiFi).
         mService.setUnderlyingNetworksForVpn(null);
@@ -5922,7 +6052,7 @@
 
         assertTrue(mCm.isActiveNetworkMetered());
 
-        vpnNetworkAgent.disconnect();
+        mMockVpn.disconnect();
     }
 
     @Test
@@ -6084,12 +6214,13 @@
     }
 
     /**
-     * Make simulated InterfaceConfig for Nat464Xlat to query clat lower layer info.
+     * Make simulated InterfaceConfigParcel for Nat464Xlat to query clat lower layer info.
      */
-    private InterfaceConfiguration getClatInterfaceConfig(LinkAddress la) {
-        InterfaceConfiguration cfg = new InterfaceConfiguration();
-        cfg.setHardwareAddress("11:22:33:44:55:66");
-        cfg.setLinkAddress(la);
+    private InterfaceConfigurationParcel getClatInterfaceConfigParcel(LinkAddress la) {
+        final InterfaceConfigurationParcel cfg = new InterfaceConfigurationParcel();
+        cfg.hwAddr = "11:22:33:44:55:66";
+        cfg.ipv4Addr = la.getAddress().getHostAddress();
+        cfg.prefixLength = la.getPrefixLength();
         return cfg;
     }
 
@@ -6180,8 +6311,8 @@
         reset(mNetworkManagementService);
         reset(mMockNetd);
         reset(mMockDnsResolver);
-        when(mNetworkManagementService.getInterfaceConfig(CLAT_PREFIX + MOBILE_IFNAME))
-                .thenReturn(getClatInterfaceConfig(myIpv4));
+        when(mMockNetd.interfaceGetCfg(CLAT_PREFIX + MOBILE_IFNAME))
+                .thenReturn(getClatInterfaceConfigParcel(myIpv4));
 
         // Remove IPv4 address. Expect prefix discovery to be started again.
         cellLp.removeLinkAddress(myIpv4);
@@ -6230,7 +6361,8 @@
                     TYPE_MOBILE);
         }
         reset(mMockNetd);
-
+        when(mMockNetd.interfaceGetCfg(CLAT_PREFIX + MOBILE_IFNAME))
+                .thenReturn(getClatInterfaceConfigParcel(myIpv4));
         // Change the NAT64 prefix without first removing it.
         // Expect clatd to be stopped and started with the new prefix.
         mService.mNetdEventCallback.onNat64PrefixEvent(cellNetId, true /* added */,
@@ -6279,8 +6411,8 @@
         reset(mNetworkManagementService);
         reset(mMockNetd);
         reset(mMockDnsResolver);
-        when(mNetworkManagementService.getInterfaceConfig(CLAT_PREFIX + MOBILE_IFNAME))
-                .thenReturn(getClatInterfaceConfig(myIpv4));
+        when(mMockNetd.interfaceGetCfg(CLAT_PREFIX + MOBILE_IFNAME))
+                .thenReturn(getClatInterfaceConfigParcel(myIpv4));
 
         // Stopping prefix discovery causes netd to tell us that the NAT64 prefix is gone.
         mService.mNetdEventCallback.onNat64PrefixEvent(cellNetId, false /* added */,
@@ -6320,6 +6452,7 @@
         networkCallback.expectLinkPropertiesThat(mCellNetworkAgent,
                 (lp) -> lp.getStackedLinks().size() == 0);
         verify(mMockNetd, times(1)).networkRemoveInterface(cellNetId, CLAT_PREFIX + MOBILE_IFNAME);
+        verify(mMockNetd, times(1)).interfaceGetCfg(CLAT_PREFIX + MOBILE_IFNAME);
         verifyNoMoreInteractions(mMockNetd);
         // Clean up.
         mCellNetworkAgent.disconnect();
@@ -6651,34 +6784,21 @@
         waitForIdle();
         assertNull(mService.getProxyForNetwork(null));
 
-        // Set up a VPN network with a proxy
-        final int uid = Process.myUid();
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN);
-        final ArraySet<UidRange> ranges = new ArraySet<>();
-        ranges.add(new UidRange(uid, uid));
-        mMockVpn.setUids(ranges);
+        // Connect a VPN network with a proxy.
         LinkProperties testLinkProperties = new LinkProperties();
         testLinkProperties.setHttpProxy(testProxyInfo);
-        vpnNetworkAgent.sendLinkProperties(testLinkProperties);
-        waitForIdle();
-
-        // Connect to VPN with proxy
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        vpnNetworkAgent.connect(true);
-        mMockVpn.connect();
-        waitForIdle();
+        mMockVpn.establishForMyUid(testLinkProperties);
 
         // Test that the VPN network returns a proxy, and the WiFi does not.
-        assertEquals(testProxyInfo, mService.getProxyForNetwork(vpnNetworkAgent.getNetwork()));
+        assertEquals(testProxyInfo, mService.getProxyForNetwork(mMockVpn.getNetwork()));
         assertEquals(testProxyInfo, mService.getProxyForNetwork(null));
         assertNull(mService.getProxyForNetwork(mWiFiNetworkAgent.getNetwork()));
 
         // Test that the VPN network returns no proxy when it is set to null.
         testLinkProperties.setHttpProxy(null);
-        vpnNetworkAgent.sendLinkProperties(testLinkProperties);
+        mMockVpn.sendLinkProperties(testLinkProperties);
         waitForIdle();
-        assertNull(mService.getProxyForNetwork(vpnNetworkAgent.getNetwork()));
+        assertNull(mService.getProxyForNetwork(mMockVpn.getNetwork()));
         assertNull(mService.getProxyForNetwork(null));
 
         // Set WiFi proxy and check that the vpn proxy is still null.
@@ -6689,7 +6809,7 @@
 
         // Disconnect from VPN and check that the active network, which is now the WiFi, has the
         // correct proxy setting.
-        vpnNetworkAgent.disconnect();
+        mMockVpn.disconnect();
         waitForIdle();
         assertEquals(mWiFiNetworkAgent.getNetwork(), mCm.getActiveNetwork());
         assertEquals(testProxyInfo, mService.getProxyForNetwork(mWiFiNetworkAgent.getNetwork()));
@@ -6704,7 +6824,7 @@
         lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), RTN_UNREACHABLE));
         // The uid range needs to cover the test app so the network is visible to it.
         final Set<UidRange> vpnRange = Collections.singleton(UidRange.createForUser(VPN_USER));
-        final TestNetworkAgentWrapper vpnNetworkAgent = establishVpn(lp, VPN_UID, vpnRange);
+        mMockVpn.establish(lp, VPN_UID, vpnRange);
 
         // Connected VPN should have interface rules set up. There are two expected invocations,
         // one during VPN uid update, one during VPN LinkProperties update
@@ -6714,7 +6834,7 @@
         assertContainsExactly(uidCaptor.getAllValues().get(1), APP1_UID, APP2_UID);
         assertTrue(mService.mPermissionMonitor.getVpnUidRanges("tun0").equals(vpnRange));
 
-        vpnNetworkAgent.disconnect();
+        mMockVpn.disconnect();
         waitForIdle();
 
         // Disconnected VPN should have interface rules removed
@@ -6731,8 +6851,7 @@
         lp.addRoute(new RouteInfo(new IpPrefix(Inet4Address.ANY, 0), null));
         // The uid range needs to cover the test app so the network is visible to it.
         final Set<UidRange> vpnRange = Collections.singleton(UidRange.createForUser(VPN_USER));
-        final TestNetworkAgentWrapper vpnNetworkAgent = establishVpn(
-                lp, Process.SYSTEM_UID, vpnRange);
+        mMockVpn.establish(lp, Process.SYSTEM_UID, vpnRange);
 
         // Legacy VPN should not have interface rules set up
         verify(mMockNetd, never()).firewallAddUidInterfaceRules(any(), any());
@@ -6747,8 +6866,7 @@
         lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), RTN_UNREACHABLE));
         // The uid range needs to cover the test app so the network is visible to it.
         final Set<UidRange> vpnRange = Collections.singleton(UidRange.createForUser(VPN_USER));
-        final TestNetworkAgentWrapper vpnNetworkAgent = establishVpn(
-                lp, Process.SYSTEM_UID, vpnRange);
+        mMockVpn.establish(lp, Process.SYSTEM_UID, vpnRange);
 
         // IPv6 unreachable route should not be misinterpreted as a default route
         verify(mMockNetd, never()).firewallAddUidInterfaceRules(any(), any());
@@ -6762,7 +6880,7 @@
         lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), null));
         // The uid range needs to cover the test app so the network is visible to it.
         final Set<UidRange> vpnRange = Collections.singleton(UidRange.createForUser(VPN_USER));
-        final TestNetworkAgentWrapper vpnNetworkAgent = establishVpn(lp, VPN_UID, vpnRange);
+        mMockVpn.establish(lp, VPN_UID, vpnRange);
 
         // Connected VPN should have interface rules set up. There are two expected invocations,
         // one during VPN uid update, one during VPN LinkProperties update
@@ -6774,7 +6892,7 @@
         reset(mMockNetd);
         InOrder inOrder = inOrder(mMockNetd);
         lp.setInterfaceName("tun1");
-        vpnNetworkAgent.sendLinkProperties(lp);
+        mMockVpn.sendLinkProperties(lp);
         waitForIdle();
         // VPN handover (switch to a new interface) should result in rules being updated (old rules
         // removed first, then new rules added)
@@ -6787,7 +6905,7 @@
         lp = new LinkProperties();
         lp.setInterfaceName("tun1");
         lp.addRoute(new RouteInfo(new IpPrefix("192.0.2.0/24"), null, "tun1"));
-        vpnNetworkAgent.sendLinkProperties(lp);
+        mMockVpn.sendLinkProperties(lp);
         waitForIdle();
         // VPN not routing everything should no longer have interface filtering rules
         verify(mMockNetd).firewallRemoveUidInterfaceRules(uidCaptor.capture());
@@ -6798,7 +6916,7 @@
         lp.setInterfaceName("tun1");
         lp.addRoute(new RouteInfo(new IpPrefix(Inet4Address.ANY, 0), RTN_UNREACHABLE));
         lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), null));
-        vpnNetworkAgent.sendLinkProperties(lp);
+        mMockVpn.sendLinkProperties(lp);
         waitForIdle();
         // Back to routing all IPv6 traffic should have filtering rules
         verify(mMockNetd).firewallAddUidInterfaceRules(eq("tun1"), uidCaptor.capture());
@@ -6813,8 +6931,7 @@
         lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), null));
         // The uid range needs to cover the test app so the network is visible to it.
         final UidRange vpnRange = UidRange.createForUser(VPN_USER);
-        final TestNetworkAgentWrapper vpnNetworkAgent = establishVpn(lp, VPN_UID,
-                Collections.singleton(vpnRange));
+        mMockVpn.establish(lp, VPN_UID, Collections.singleton(vpnRange));
 
         reset(mMockNetd);
         InOrder inOrder = inOrder(mMockNetd);
@@ -6823,7 +6940,7 @@
         final Set<UidRange> newRanges = new HashSet<>(Arrays.asList(
                 new UidRange(vpnRange.start, APP1_UID - 1),
                 new UidRange(APP1_UID + 1, vpnRange.stop)));
-        vpnNetworkAgent.setUids(newRanges);
+        mMockVpn.setUids(newRanges);
         waitForIdle();
 
         ArgumentCaptor<int[]> uidCaptor = ArgumentCaptor.forClass(int[].class);
@@ -6964,7 +7081,7 @@
     private void setupConnectionOwnerUid(int vpnOwnerUid, @VpnManager.VpnType int vpnType)
             throws Exception {
         final Set<UidRange> vpnRange = Collections.singleton(UidRange.createForUser(VPN_USER));
-        establishVpn(new LinkProperties(), vpnOwnerUid, vpnRange);
+        mMockVpn.establish(new LinkProperties(), vpnOwnerUid, vpnRange);
         mMockVpn.setVpnType(vpnType);
 
         final VpnInfo vpnInfo = new VpnInfo();
@@ -7045,19 +7162,6 @@
         mService.getConnectionOwnerUid(getTestConnectionInfo());
     }
 
-    private TestNetworkAgentWrapper establishVpn(
-            LinkProperties lp, int ownerUid, Set<UidRange> vpnRange) throws Exception {
-        final TestNetworkAgentWrapper
-                vpnNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_VPN, lp);
-        vpnNetworkAgent.getNetworkCapabilities().setOwnerUid(ownerUid);
-        mMockVpn.setNetworkAgent(vpnNetworkAgent);
-        mMockVpn.connect();
-        mMockVpn.setUids(vpnRange);
-        vpnNetworkAgent.connect(true);
-        waitForIdle();
-        return vpnNetworkAgent;
-    }
-
     private static PackageInfo buildPackageInfo(boolean hasSystemPermission, int uid) {
         final PackageInfo packageInfo = new PackageInfo();
         if (hasSystemPermission) {
@@ -7237,22 +7341,28 @@
 
         setupLocationPermissions(Build.VERSION_CODES.Q, true, AppOpsManager.OPSTR_FINE_LOCATION,
                 Manifest.permission.ACCESS_FINE_LOCATION);
-        mServiceContext.setPermission(android.Manifest.permission.NETWORK_STACK, PERMISSION_DENIED);
 
         // setUp() calls mockVpn() which adds a VPN with the Test Runner's uid. Configure it to be
         // active
         final VpnInfo info = new VpnInfo();
         info.ownerUid = Process.myUid();
-        info.vpnIface = "interface";
+        info.vpnIface = VPN_IFNAME;
         mMockVpn.setVpnInfo(info);
-        mMockVpn.overrideUnderlyingNetworks(new Network[] {network});
+
+        mMockVpn.establishForMyUid();
+        waitForIdle();
+
+        mServiceContext.setPermission(android.Manifest.permission.NETWORK_STACK, PERMISSION_DENIED);
+
+
+        assertTrue(mService.setUnderlyingNetworksForVpn(new Network[] {network}));
         assertTrue(
                 "Active VPN permission not applied",
                 mService.checkConnectivityDiagnosticsPermissions(
                         Process.myPid(), Process.myUid(), naiWithoutUid,
                         mContext.getOpPackageName()));
 
-        mMockVpn.overrideUnderlyingNetworks(null);
+        assertTrue(mService.setUnderlyingNetworksForVpn(null));
         assertFalse(
                 "VPN shouldn't receive callback on non-underlying network",
                 mService.checkConnectivityDiagnosticsPermissions(
@@ -7273,8 +7383,6 @@
                 Manifest.permission.ACCESS_FINE_LOCATION);
         mServiceContext.setPermission(android.Manifest.permission.NETWORK_STACK, PERMISSION_DENIED);
 
-        // Disconnect mock vpn so the uid check on NetworkAgentInfo is tested
-        mMockVpn.disconnect();
         assertTrue(
                 "NetworkCapabilities administrator uid permission not applied",
                 mService.checkConnectivityDiagnosticsPermissions(
diff --git a/tests/net/java/com/android/server/connectivity/Nat464XlatTest.java b/tests/net/java/com/android/server/connectivity/Nat464XlatTest.java
index 5046b65..4f65b67 100644
--- a/tests/net/java/com/android/server/connectivity/Nat464XlatTest.java
+++ b/tests/net/java/com/android/server/connectivity/Nat464XlatTest.java
@@ -29,7 +29,7 @@
 import android.net.ConnectivityManager;
 import android.net.IDnsResolver;
 import android.net.INetd;
-import android.net.InterfaceConfiguration;
+import android.net.InterfaceConfigurationParcel;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
@@ -68,7 +68,6 @@
     @Mock IDnsResolver mDnsResolver;
     @Mock INetd mNetd;
     @Mock INetworkManagementService mNms;
-    @Mock InterfaceConfiguration mConfig;
     @Mock NetworkAgentInfo mNai;
 
     TestLooper mLooper;
@@ -106,9 +105,10 @@
         when(mNai.connService()).thenReturn(mConnectivity);
         when(mNai.netAgentConfig()).thenReturn(mAgentConfig);
         when(mNai.handler()).thenReturn(mHandler);
-
-        when(mNms.getInterfaceConfig(eq(STACKED_IFACE))).thenReturn(mConfig);
-        when(mConfig.getLinkAddress()).thenReturn(ADDR);
+        final InterfaceConfigurationParcel mConfig = new InterfaceConfigurationParcel();
+        when(mNetd.interfaceGetCfg(eq(STACKED_IFACE))).thenReturn(mConfig);
+        mConfig.ipv4Addr = ADDR.getAddress().getHostAddress();
+        mConfig.prefixLength =  ADDR.getPrefixLength();
     }
 
     private void assertRequiresClat(boolean expected, NetworkAgentInfo nai) {
@@ -213,7 +213,7 @@
         nat.interfaceLinkStateChanged(STACKED_IFACE, true);
         mLooper.dispatchNext();
 
-        verify(mNms).getInterfaceConfig(eq(STACKED_IFACE));
+        verify(mNetd).interfaceGetCfg(eq(STACKED_IFACE));
         verify(mConnectivity).handleUpdateLinkProperties(eq(mNai), c.capture());
         assertFalse(c.getValue().getStackedLinks().isEmpty());
         assertTrue(c.getValue().getAllInterfaceNames().contains(STACKED_IFACE));
@@ -353,7 +353,7 @@
         nat.interfaceLinkStateChanged(STACKED_IFACE, true);
         mLooper.dispatchNext();
 
-        verify(mNms).getInterfaceConfig(eq(STACKED_IFACE));
+        verify(mNetd).interfaceGetCfg(eq(STACKED_IFACE));
         verify(mConnectivity, times(1)).handleUpdateLinkProperties(eq(mNai), c.capture());
         assertFalse(c.getValue().getStackedLinks().isEmpty());
         assertTrue(c.getValue().getAllInterfaceNames().contains(STACKED_IFACE));
diff --git a/tests/net/java/com/android/server/net/NetworkStatsServiceTest.java b/tests/net/java/com/android/server/net/NetworkStatsServiceTest.java
index 7abe189..cd9406c 100644
--- a/tests/net/java/com/android/server/net/NetworkStatsServiceTest.java
+++ b/tests/net/java/com/android/server/net/NetworkStatsServiceTest.java
@@ -35,7 +35,6 @@
 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;
@@ -994,7 +993,7 @@
     public void testTethering() throws Exception {
         // pretend first mobile network comes online
         expectDefaultSettings();
-        NetworkState[] states = new NetworkState[] {buildMobile3gState(IMSI_1)};
+        final NetworkState[] states = new NetworkState[]{buildMobile3gState(IMSI_1)};
         expectNetworkStatsSummary(buildEmptyStats());
         expectNetworkStatsUidDetail(buildEmptyStats());
 
@@ -1004,23 +1003,39 @@
         incrementCurrentTime(HOUR_IN_MILLIS);
         expectDefaultSettings();
 
+        // Register custom provider and retrieve callback.
+        final TestableNetworkStatsProviderBinder provider =
+                new TestableNetworkStatsProviderBinder();
+        final INetworkStatsProviderCallback cb =
+                mService.registerNetworkStatsProvider("TEST-TETHERING-OFFLOAD", provider);
+        assertNotNull(cb);
+        final long now = getElapsedRealtime();
+
         // Traffic seen by kernel counters (includes software tethering).
-        final NetworkStats ifaceStats = new NetworkStats(getElapsedRealtime(), 1)
+        final NetworkStats swIfaceStats = new NetworkStats(now, 1)
                 .insertEntry(TEST_IFACE, 1536L, 12L, 384L, 3L);
         // Hardware tethering traffic, not seen by kernel counters.
-        final NetworkStats tetherStatsHardware = new NetworkStats(getElapsedRealtime(), 1)
-                .insertEntry(TEST_IFACE, 512L, 4L, 128L, 1L);
+        final NetworkStats tetherHwIfaceStats = new NetworkStats(now, 1)
+                .insertEntry(new NetworkStats.Entry(TEST_IFACE, UID_ALL, SET_DEFAULT,
+                        TAG_NONE, METERED_YES, ROAMING_NO, DEFAULT_NETWORK_YES,
+                        512L, 4L, 128L, 1L, 0L));
+        final NetworkStats tetherHwUidStats = new NetworkStats(now, 1)
+                .insertEntry(new NetworkStats.Entry(TEST_IFACE, UID_TETHERING, SET_DEFAULT,
+                        TAG_NONE, METERED_YES, ROAMING_NO, DEFAULT_NETWORK_YES,
+                        512L, 4L, 128L, 1L, 0L));
+        cb.notifyStatsUpdated(0 /* unused */, tetherHwIfaceStats, tetherHwUidStats);
 
-        // Traffic for UID_RED.
-        final NetworkStats uidStats = new NetworkStats(getElapsedRealtime(), 1)
+        // Fake some traffic done by apps on the device (as opposed to tethering), and record it
+        // into UID stats (as opposed to iface stats).
+        final NetworkStats localUidStats = new NetworkStats(now, 1)
                 .insertEntry(TEST_IFACE, UID_RED, SET_DEFAULT, TAG_NONE, 128L, 2L, 128L, 2L, 0L);
-        // All tethering traffic, both hardware and software.
-        final NetworkStats tetherStats = new NetworkStats(getElapsedRealtime(), 1)
-                .insertEntry(TEST_IFACE, UID_TETHERING, SET_DEFAULT, TAG_NONE, 1920L, 14L, 384L, 2L,
+        // Software per-uid tethering traffic.
+        final NetworkStats tetherSwUidStats = new NetworkStats(now, 1)
+                .insertEntry(TEST_IFACE, UID_TETHERING, SET_DEFAULT, TAG_NONE, 1408L, 10L, 256L, 1L,
                         0L);
 
-        expectNetworkStatsSummary(ifaceStats, tetherStatsHardware);
-        expectNetworkStatsUidDetail(uidStats, tetherStats);
+        expectNetworkStatsSummary(swIfaceStats);
+        expectNetworkStatsUidDetail(localUidStats, tetherSwUidStats);
         forcePollAndWaitForIdle();
 
         // verify service recorded history
@@ -1362,12 +1377,6 @@
     }
 
     private void expectNetworkStatsSummary(NetworkStats summary) throws Exception {
-        expectNetworkStatsSummary(summary, new NetworkStats(0L, 0));
-    }
-
-    private void expectNetworkStatsSummary(NetworkStats summary, NetworkStats tetherStats)
-            throws Exception {
-        expectNetworkStatsTethering(STATS_PER_IFACE, tetherStats);
         expectNetworkStatsSummaryDev(summary.clone());
         expectNetworkStatsSummaryXt(summary.clone());
     }
@@ -1380,11 +1389,6 @@
         when(mStatsFactory.readNetworkStatsSummaryXt()).thenReturn(summary);
     }
 
-    private void expectNetworkStatsTethering(int how, NetworkStats stats)
-            throws Exception {
-        when(mNetManager.getNetworkStatsTethering(how)).thenReturn(stats);
-    }
-
     private void expectNetworkStatsUidDetail(NetworkStats detail) throws Exception {
         expectNetworkStatsUidDetail(detail, new NetworkStats(0L, 0));
     }