Make Ethernet interfaces more testable.

This CL adds a setIncludeTestInterfaces method to EthernetManager
that, when called, causes the Ethernet service to recognize and
manage test interfaces created by TestNetworkManager.

Bug: 150644681
Test: Tested by EthernetTetheringTest in same topic
Change-Id: I86eef7a93267f800dbfc8eafd307effa76a344ca

api/test-current.txt

@@ -1442,6 +1442,7 @@ package android.net {
 
   public class EthernetManager {
     method @NonNull @RequiresPermission(anyOf={android.Manifest.permission.NETWORK_STACK, android.net.NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK}) public android.net.EthernetManager.TetheredInterfaceRequest requestTetheredInterface(@NonNull java.util.concurrent.Executor, @NonNull android.net.EthernetManager.TetheredInterfaceCallback);
+    method public void setIncludeTestInterfaces(boolean);
   }
 
   public static interface EthernetManager.TetheredInterfaceCallback {

core/java/android/net/EthernetManager.java

@@ -199,6 +199,21 @@ public class EthernetManager {
         }
     }
 
+    /**
+     * Whether to treat interfaces created by {@link TestNetworkManager#createTapInterface}
+     * as Ethernet interfaces. The effects of this method apply to any test interfaces that are
+     * already present on the system.
+     * @hide
+     */
+    @TestApi
+    public void setIncludeTestInterfaces(boolean include) {
+        try {
+            mService.setIncludeTestInterfaces(include);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     /**
      * A request for a tethered interface.
      */

core/java/android/net/IEthernetManager.aidl

@@ -33,6 +33,7 @@ interface IEthernetManager
     boolean isAvailable(String iface);
     void addListener(in IEthernetServiceListener listener);
     void removeListener(in IEthernetServiceListener listener);
+    void setIncludeTestInterfaces(boolean include);
     void requestTetheredInterface(in ITetheredInterfaceCallback callback);
     void releaseTetheredInterface(in ITetheredInterfaceCallback callback);
 }

core/java/android/net/TestNetworkManager.java

@@ -30,6 +30,18 @@ import com.android.internal.util.Preconditions;
  */
 @TestApi
 public class TestNetworkManager {
+    /**
+     * Prefix for tun interfaces created by this class.
+     * @hide
+     */
+    public static final String TEST_TUN_PREFIX = "testtun";
+
+    /**
+     * Prefix for tap interfaces created by this class.
+     * @hide
+     */
+    public static final String TEST_TAP_PREFIX = "testtap";
+
     @NonNull private static final String TAG = TestNetworkManager.class.getSimpleName();
 
     @NonNull private final ITestNetworkManager mService;

services/core/java/com/android/server/TestNetworkService.java

@@ -16,6 +16,9 @@
 
 package com.android.server;
 
+import static android.net.TestNetworkManager.TEST_TAP_PREFIX;
+import static android.net.TestNetworkManager.TEST_TUN_PREFIX;
+
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.Context;
@@ -61,8 +64,6 @@ import java.util.concurrent.atomic.AtomicInteger;
 class TestNetworkService extends ITestNetworkManager.Stub {
     @NonNull private static final String TAG = TestNetworkService.class.getSimpleName();
     @NonNull private static final String TEST_NETWORK_TYPE = "TEST_NETWORK";
-    @NonNull private static final String TEST_TUN_PREFIX = "testtun";
-    @NonNull private static final String TEST_TAP_PREFIX = "testtap";
     @NonNull private static final AtomicInteger sTestTunIndex = new AtomicInteger();
 
     @NonNull private final Context mContext;