diff --git a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
index 4f15355..342d507 100644
--- a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
+++ b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
@@ -183,7 +183,8 @@
      * Returns an array of available interface names. The array is sorted: unrestricted interfaces
      * goes first, then sorted by name.
      */
-    String[] getAvailableInterfaces(boolean includeRestricted) {
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected String[] getAvailableInterfaces(boolean includeRestricted) {
         return mTrackingInterfaces.values()
                 .stream()
                 .filter(iface -> !iface.isRestricted() || includeRestricted)
@@ -195,7 +196,8 @@
                 .toArray(String[]::new);
     }
 
-    void addInterface(@NonNull final String ifaceName, @NonNull final String hwAddress,
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected void addInterface(@NonNull final String ifaceName, @NonNull final String hwAddress,
             @NonNull final IpConfiguration ipConfig,
             @NonNull final NetworkCapabilities capabilities) {
         if (mTrackingInterfaces.containsKey(ifaceName)) {
@@ -282,7 +284,8 @@
                 .addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET).build();
     }
 
-    void removeInterface(String interfaceName) {
+    @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
+    protected void removeInterface(String interfaceName) {
         NetworkInterfaceState iface = mTrackingInterfaces.remove(interfaceName);
         if (iface != null) {
             iface.maybeSendNetworkManagementCallbackForAbort();
diff --git a/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
index edda321..afed01a 100644
--- a/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
+++ b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
@@ -281,4 +281,12 @@
 
         mTracker.disconnectNetwork(iface, listener);
     }
+
+    @Override
+    public void setEthernetEnabled(boolean enabled) {
+        PermissionUtils.enforceNetworkStackPermissionOr(mContext,
+                android.Manifest.permission.NETWORK_SETTINGS);
+
+        mTracker.setEthernetEnabled(enabled);
+    }
 }
diff --git a/service-t/src/com/android/server/ethernet/EthernetTracker.java b/service-t/src/com/android/server/ethernet/EthernetTracker.java
index 0a0e327..c38c900 100644
--- a/service-t/src/com/android/server/ethernet/EthernetTracker.java
+++ b/service-t/src/com/android/server/ethernet/EthernetTracker.java
@@ -16,6 +16,8 @@
 
 package com.android.server.ethernet;
 
+import static android.net.EthernetManager.ETHERNET_STATE_DISABLED;
+import static android.net.EthernetManager.ETHERNET_STATE_ENABLED;
 import static android.net.TestNetworkManager.TEST_TAP_PREFIX;
 
 import static com.android.internal.annotations.VisibleForTesting.Visibility.PACKAGE;
@@ -119,6 +121,8 @@
     private boolean mTetheredInterfaceWasAvailable = false;
     private volatile IpConfiguration mIpConfigForDefaultInterface;
 
+    private int mEthernetState = ETHERNET_STATE_ENABLED;
+
     private class TetheredInterfaceRequestList extends
             RemoteCallbackList<ITetheredInterfaceCallback> {
         @Override
@@ -355,6 +359,8 @@
             for (String iface : getInterfaces(canUseRestrictedNetworks)) {
                 unicastInterfaceStateChange(listener, iface);
             }
+
+            unicastEthernetStateChange(listener, mEthernetState);
         });
     }
 
@@ -825,6 +831,53 @@
         }
     }
 
+    @VisibleForTesting(visibility = PACKAGE)
+    protected void setEthernetEnabled(boolean enabled) {
+        mHandler.post(() -> {
+            int newState = enabled ? ETHERNET_STATE_ENABLED : ETHERNET_STATE_DISABLED;
+            if (mEthernetState == newState) return;
+
+            mEthernetState = newState;
+
+            if (enabled) {
+                trackAvailableInterfaces();
+            } else {
+                // TODO: maybe also disable server mode interface as well.
+                untrackFactoryInterfaces();
+            }
+            broadcastEthernetStateChange(mEthernetState);
+        });
+    }
+
+    private void untrackFactoryInterfaces() {
+        for (String iface : mFactory.getAvailableInterfaces(true /* includeRestricted */)) {
+            stopTrackingInterface(iface);
+        }
+    }
+
+    private void unicastEthernetStateChange(@NonNull IEthernetServiceListener listener,
+            int state) {
+        ensureRunningOnEthernetServiceThread();
+        try {
+            listener.onEthernetStateChanged(state);
+        } catch (RemoteException e) {
+            // Do nothing here.
+        }
+    }
+
+    private void broadcastEthernetStateChange(int state) {
+        ensureRunningOnEthernetServiceThread();
+        final int n = mListeners.beginBroadcast();
+        for (int i = 0; i < n; i++) {
+            try {
+                mListeners.getBroadcastItem(i).onEthernetStateChanged(state);
+            } catch (RemoteException e) {
+                // Do nothing here.
+            }
+        }
+        mListeners.finishBroadcast();
+    }
+
     void dump(FileDescriptor fd, IndentingPrintWriter pw, String[] args) {
         postAndWaitForRunnable(() -> {
             pw.println(getClass().getSimpleName());
diff --git a/tests/ethernet/java/com/android/server/ethernet/EthernetServiceImplTest.java b/tests/ethernet/java/com/android/server/ethernet/EthernetServiceImplTest.java
index e67c4c8..dd1f1ed 100644
--- a/tests/ethernet/java/com/android/server/ethernet/EthernetServiceImplTest.java
+++ b/tests/ethernet/java/com/android/server/ethernet/EthernetServiceImplTest.java
@@ -19,12 +19,15 @@
 import static android.net.NetworkCapabilities.TRANSPORT_TEST;
 
 import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.fail;
 
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.isNull;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -339,4 +342,31 @@
         mEthernetServiceImpl.disconnectNetwork(TEST_IFACE, NULL_LISTENER);
         verify(mEthernetTracker).disconnectNetwork(eq(TEST_IFACE), eq(NULL_LISTENER));
     }
+
+    private void denyPermissions(String... permissions) {
+        for (String permission: permissions) {
+            doReturn(PackageManager.PERMISSION_DENIED).when(mContext)
+                    .checkCallingOrSelfPermission(eq(permission));
+        }
+    }
+
+    @Test
+    public void testSetEthernetEnabled() {
+        denyPermissions(android.net.NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK);
+        mEthernetServiceImpl.setEthernetEnabled(true);
+        verify(mEthernetTracker).setEthernetEnabled(true);
+        reset(mEthernetTracker);
+
+        denyPermissions(Manifest.permission.NETWORK_STACK);
+        mEthernetServiceImpl.setEthernetEnabled(false);
+        verify(mEthernetTracker).setEthernetEnabled(false);
+        reset(mEthernetTracker);
+
+        denyPermissions(Manifest.permission.NETWORK_SETTINGS);
+        try {
+            mEthernetServiceImpl.setEthernetEnabled(true);
+            fail("Should get SecurityException");
+        } catch (SecurityException e) { }
+        verify(mEthernetTracker, never()).setEthernetEnabled(false);
+    }
 }
diff --git a/tests/ethernet/java/com/android/server/ethernet/EthernetTrackerTest.java b/tests/ethernet/java/com/android/server/ethernet/EthernetTrackerTest.java
index bab9643..b1831c4 100644
--- a/tests/ethernet/java/com/android/server/ethernet/EthernetTrackerTest.java
+++ b/tests/ethernet/java/com/android/server/ethernet/EthernetTrackerTest.java
@@ -25,19 +25,26 @@
 import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.reset;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
 import android.content.res.Resources;
+import android.net.EthernetManager;
 import android.net.InetAddresses;
 import android.net.INetworkInterfaceOutcomeReceiver;
+import android.net.IEthernetServiceListener;
 import android.net.INetd;
 import android.net.IpConfiguration;
 import android.net.IpConfiguration.IpAssignment;
 import android.net.IpConfiguration.ProxySettings;
+import android.net.InterfaceConfigurationParcel;
 import android.net.LinkAddress;
 import android.net.NetworkCapabilities;
 import android.net.StaticIpConfiguration;
@@ -393,4 +400,57 @@
 
         assertTrue(isValidTestInterface);
     }
+
+    public static class EthernetStateListener extends IEthernetServiceListener.Stub {
+        @Override
+        public void onEthernetStateChanged(int state) { }
+
+        @Override
+        public void onInterfaceStateChanged(String iface, int state, int role,
+                IpConfiguration configuration) { }
+    }
+
+    @Test
+    public void testListenEthernetStateChange() throws Exception {
+        final String testIface = "testtap123";
+        final String testHwAddr = "11:22:33:44:55:66";
+        final InterfaceConfigurationParcel ifaceParcel = new InterfaceConfigurationParcel();
+        ifaceParcel.ifName = testIface;
+        ifaceParcel.hwAddr = testHwAddr;
+        ifaceParcel.flags = new String[] {INetd.IF_STATE_UP};
+
+        tracker.setIncludeTestInterfaces(true);
+        waitForIdle();
+
+        when(mNetd.interfaceGetList()).thenReturn(new String[] {testIface});
+        when(mNetd.interfaceGetCfg(eq(testIface))).thenReturn(ifaceParcel);
+        doReturn(new String[] {testIface}).when(mFactory).getAvailableInterfaces(anyBoolean());
+        doReturn(EthernetManager.STATE_LINK_UP).when(mFactory).getInterfaceState(eq(testIface));
+
+        final EthernetStateListener listener = spy(new EthernetStateListener());
+        tracker.addListener(listener, true /* canUseRestrictedNetworks */);
+        // Check default state.
+        waitForIdle();
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_LINK_UP),
+                anyInt(), any());
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_ENABLED));
+        reset(listener);
+
+        doReturn(EthernetManager.STATE_ABSENT).when(mFactory).getInterfaceState(eq(testIface));
+        tracker.setEthernetEnabled(false);
+        waitForIdle();
+        verify(mFactory).removeInterface(eq(testIface));
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_DISABLED));
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_ABSENT),
+                anyInt(), any());
+        reset(listener);
+
+        doReturn(EthernetManager.STATE_LINK_UP).when(mFactory).getInterfaceState(eq(testIface));
+        tracker.setEthernetEnabled(true);
+        waitForIdle();
+        verify(mFactory).addInterface(eq(testIface), eq(testHwAddr), any(), any());
+        verify(listener).onEthernetStateChanged(eq(EthernetManager.ETHERNET_STATE_ENABLED));
+        verify(listener).onInterfaceStateChanged(eq(testIface), eq(EthernetManager.STATE_LINK_UP),
+                anyInt(), any());
+    }
 }