diff --git a/framework-t/src/android/net/EthernetManager.java b/framework-t/src/android/net/EthernetManager.java
index 719f60d9cb..2f0612bd1b 100644
--- a/framework-t/src/android/net/EthernetManager.java
+++ b/framework-t/src/android/net/EthernetManager.java
@@ -281,6 +281,36 @@ public class EthernetManager {
     @SystemApi(client = MODULE_LIBRARIES)
     public void addInterfaceStateListener(@NonNull Executor executor,
             @NonNull InterfaceStateListener listener) {
+        addInterfaceStateListener(executor, listener, LISTENER_FLAG_DEFAULT);
+    }
+
+
+    /** @hide */
+    public static final int LISTENER_FLAG_DEFAULT = 0;
+
+    /**
+     * Include callbacks for NCM interfaces which are not tracked by the regex.
+     * @hide
+     */
+    public static final int LISTENER_FLAG_INCLUDE_NCM = 1 << 0;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "LISTENER_FLAG_" }, value = {
+        LISTENER_FLAG_DEFAULT,
+        LISTENER_FLAG_INCLUDE_NCM
+    })
+    public @interface ListenerFlag {}
+
+    /**
+     * Listen to ethernet interface state changes
+     *
+     * Version of {@link #addInterfaceStateListener} that accepts flags for testing.
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+    public void addInterfaceStateListener(@NonNull Executor executor,
+            @NonNull InterfaceStateListener listener, @ListenerFlag int flags) {
         if (listener == null || executor == null) {
             throw new NullPointerException("listener and executor must not be null");
         }
@@ -297,15 +327,16 @@ public class EthernetManager {
             }
         };
         synchronized (mListenerLock) {
-            addServiceListener(serviceListener);
+            addServiceListener(serviceListener, flags);
             mIfaceServiceListeners.put(listener, serviceListener);
         }
     }
 
     @GuardedBy("mListenerLock")
-    private void addServiceListener(@NonNull final IEthernetServiceListener listener) {
+    private void addServiceListener(@NonNull final IEthernetServiceListener listener,
+            @ListenerFlag int flags) {
         try {
-            mService.addListener(listener);
+            mService.addListener(listener, flags);
         } catch (RemoteException e) {
             throw e.rethrowFromSystemServer();
         }
@@ -673,7 +704,7 @@ public class EthernetManager {
                     IpConfiguration configuration) {}
         };
         synchronized (mListenerLock) {
-            addServiceListener(serviceListener);
+            addServiceListener(serviceListener, LISTENER_FLAG_DEFAULT);
             mStateServiceListeners.put(listener, serviceListener);
         }
     }
diff --git a/framework-t/src/android/net/IEthernetManager.aidl b/framework-t/src/android/net/IEthernetManager.aidl
index c1efc29d25..ea45a9de7c 100644
--- a/framework-t/src/android/net/IEthernetManager.aidl
+++ b/framework-t/src/android/net/IEthernetManager.aidl
@@ -36,7 +36,7 @@ interface IEthernetManager
     IpConfiguration getConfiguration(String iface);
     void setConfiguration(String iface, in IpConfiguration config);
     boolean isAvailable(String iface);
-    void addListener(in IEthernetServiceListener listener);
+    void addListener(in IEthernetServiceListener listener, int flags);
     void removeListener(in IEthernetServiceListener listener);
     void setIncludeTestInterfaces(boolean include);
     void requestTetheredInterface(in ITetheredInterfaceCallback callback);
diff --git a/service-t/src/com/android/server/ethernet/EthernetListener.java b/service-t/src/com/android/server/ethernet/EthernetListener.java
index b9704492fd..79b8122d9f 100644
--- a/service-t/src/com/android/server/ethernet/EthernetListener.java
+++ b/service-t/src/com/android/server/ethernet/EthernetListener.java
@@ -26,10 +26,13 @@ import android.os.RemoteException;
 public class EthernetListener implements IInterface {
     private final IEthernetServiceListener mListener;
     private final boolean mHasUseRestrictedNetworksPermission;
+    private final int mFlags;
 
-    public EthernetListener(IEthernetServiceListener listener, boolean canUseRestrictedNetworks) {
+    public EthernetListener(IEthernetServiceListener listener, boolean canUseRestrictedNetworks,
+            int flags) {
         mListener = listener;
         mHasUseRestrictedNetworksPermission = canUseRestrictedNetworks;
+        mFlags = flags;
     }
 
     /** Indicates whether the remote uid has USE_RESTRICTED_NETWORKS permission */
diff --git a/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
index 30b644876f..c1b808190a 100644
--- a/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
+++ b/service-t/src/com/android/server/ethernet/EthernetServiceImpl.java
@@ -24,6 +24,7 @@ import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.Context;
 import android.content.pm.PackageManager;
+import android.net.EthernetManager;
 import android.net.EthernetNetworkSpecifier;
 import android.net.EthernetNetworkUpdateRequest;
 import android.net.IEthernetManager;
@@ -166,7 +167,7 @@ public class EthernetServiceImpl extends IEthernetManager.Stub {
      * @param listener A {@link IEthernetServiceListener} to add.
      */
     @Override
-    public void addListener(IEthernetServiceListener listener) throws RemoteException {
+    public void addListener(IEthernetServiceListener listener, int flags) throws RemoteException {
         Objects.requireNonNull(listener, "listener must not be null");
         PermissionUtils.enforceAccessNetworkStatePermission(mContext, TAG);
         final boolean hasUseRestrictedNetworksPermission = hasUseRestrictedNetworksPermission();
@@ -174,7 +175,7 @@ public class EthernetServiceImpl extends IEthernetManager.Stub {
         final long ident = Binder.clearCallingIdentity();
         try {
             final EthernetListener wrappedListener =
-                    new EthernetListener(listener, hasUseRestrictedNetworksPermission);
+                    new EthernetListener(listener, hasUseRestrictedNetworksPermission, flags);
             mTracker.addListener(wrappedListener);
         } finally {
             Binder.restoreCallingIdentity(ident);
@@ -198,8 +199,8 @@ public class EthernetServiceImpl extends IEthernetManager.Stub {
             // extends IInterface> instead of just IInterface.
             // Note that hasUseRestrictedNetworksPermission is irrelevant in
             // this context and is only populated for the sake of completeness.
-            final EthernetListener wrappedListener =
-                    new EthernetListener(listener, hasUseRestrictedNetworksPermission);
+            final EthernetListener wrappedListener = new EthernetListener(listener,
+                    hasUseRestrictedNetworksPermission, EthernetManager.LISTENER_FLAG_DEFAULT);
             mTracker.removeListener(wrappedListener);
         } finally {
             Binder.restoreCallingIdentity(ident);