Support set test network to tethering upstream

Test: atest EthernetTetheringTest

Change-Id: Ief2a92bc6c573a6bb75c72b7a0630e5c0accfa73
diff --git a/Tethering/tests/integration/Android.bp b/Tethering/tests/integration/Android.bp
index 2593b1b..c7f5527 100644
--- a/Tethering/tests/integration/Android.bp
+++ b/Tethering/tests/integration/Android.bp
@@ -19,6 +19,7 @@
 
 java_defaults {
     name: "TetheringIntegrationTestsDefaults",
+    defaults: ["framework-connectivity-test-defaults"],
     srcs: [
         "src/**/*.java",
         "src/**/*.kt",
diff --git a/Tethering/tests/integration/AndroidManifest.xml b/Tethering/tests/integration/AndroidManifest.xml
index fddfaad..c89c556 100644
--- a/Tethering/tests/integration/AndroidManifest.xml
+++ b/Tethering/tests/integration/AndroidManifest.xml
@@ -17,6 +17,11 @@
           package="com.android.networkstack.tethering.tests.integration">
 
     <uses-permission android:name="android.permission.INTERNET"/>
+    <!-- The test need CHANGE_NETWORK_STATE permission to use requestNetwork API to setup test
+         network. Since R shell application don't have such permission, grant permission to the test
+         here. TODO: Remove CHANGE_NETWORK_STATE permission here and use adopt shell perssion to
+         obtain CHANGE_NETWORK_STATE for testing once R device is no longer supported. -->
+    <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"/>
 
     <application android:debuggable="true">
         <uses-library android:name="android.test.runner" />
diff --git a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
index 26297a2..3d52d45 100644
--- a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
+++ b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
@@ -21,6 +21,7 @@
 import static android.Manifest.permission.MANAGE_TEST_NETWORKS;
 import static android.Manifest.permission.NETWORK_SETTINGS;
 import static android.Manifest.permission.TETHER_PRIVILEGED;
+import static android.net.InetAddresses.parseNumericAddress;
 import static android.net.TetheringManager.CONNECTIVITY_SCOPE_GLOBAL;
 import static android.net.TetheringManager.CONNECTIVITY_SCOPE_LOCAL;
 import static android.net.TetheringManager.TETHERING_ETHERNET;
@@ -29,6 +30,7 @@
 import static com.android.net.module.util.ConnectivityUtils.isIPv6ULA;
 import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_IPV6;
 import static com.android.net.module.util.NetworkStackConstants.ICMPV6_ROUTER_ADVERTISEMENT;
+import static com.android.testutils.TestNetworkTrackerKt.initTestNetwork;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
@@ -65,6 +67,7 @@
 import com.android.net.module.util.structs.Ipv6Header;
 import com.android.testutils.HandlerUtils;
 import com.android.testutils.TapPacketReader;
+import com.android.testutils.TestNetworkTracker;
 
 import org.junit.After;
 import org.junit.Before;
@@ -78,6 +81,7 @@
 import java.net.NetworkInterface;
 import java.net.SocketException;
 import java.nio.ByteBuffer;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.Random;
@@ -102,12 +106,16 @@
             DhcpPacket.DHCP_LEASE_TIME,
     };
     private static final String DHCP_HOSTNAME = "testhostname";
+    private static final LinkAddress TEST_IP4_ADDR = new LinkAddress("10.0.0.1/8");
+    private static final LinkAddress TEST_IP6_ADDR = new LinkAddress("2001:db8:1::101/64");
+    private static final InetAddress TEST_IP4_DNS = parseNumericAddress("8.8.8.8");
+    private static final InetAddress TEST_IP6_DNS = parseNumericAddress("2001:db8:1::888");
 
     private final Context mContext = InstrumentationRegistry.getContext();
     private final EthernetManager mEm = mContext.getSystemService(EthernetManager.class);
     private final TetheringManager mTm = mContext.getSystemService(TetheringManager.class);
 
-    private TestNetworkInterface mTestIface;
+    private TestNetworkInterface mDownstreamIface;
     private HandlerThread mHandlerThread;
     private Handler mHandler;
     private TapPacketReader mTapPacketReader;
@@ -119,6 +127,8 @@
             InstrumentationRegistry.getInstrumentation().getUiAutomation();
     private boolean mRunTests;
 
+    private TestNetworkTracker mUpstreamTracker;
+
     @Before
     public void setUp() throws Exception {
         // Needed to create a TestNetworkInterface, to call requestTetheredInterface, and to receive
@@ -138,6 +148,13 @@
     }
 
     private void cleanUp() throws Exception {
+        mTm.setPreferTestNetworks(false);
+
+        if (mUpstreamTracker != null) {
+            mUpstreamTracker.teardown();
+            mUpstreamTracker = null;
+        }
+
         mTm.stopTethering(TETHERING_ETHERNET);
         if (mTetheringEventCallback != null) {
             mTetheringEventCallback.awaitInterfaceUntethered();
@@ -169,21 +186,21 @@
         // This test requires manipulating packets. Skip if there is a physical Ethernet connected.
         assumeFalse(mEm.isAvailable());
 
-        mTestIface = createTestInterface();
+        mDownstreamIface = createTestInterface();
         // This must be done now because as soon as setIncludeTestInterfaces(true) is called, the
         // interface will be placed in client mode, which will delete the link-local address.
         // At that point NetworkInterface.getByName() will cease to work on the interface, because
         // starting in R NetworkInterface can no longer see interfaces without IP addresses.
-        int mtu = getMTU(mTestIface);
+        int mtu = getMTU(mDownstreamIface);
 
         Log.d(TAG, "Including test interfaces");
         mEm.setIncludeTestInterfaces(true);
 
         final String iface = mTetheredInterfaceRequester.getInterface();
         assertEquals("TetheredInterfaceCallback for unexpected interface",
-                mTestIface.getInterfaceName(), iface);
+                mDownstreamIface.getInterfaceName(), iface);
 
-        checkVirtualEthernet(mTestIface, mtu);
+        checkVirtualEthernet(mDownstreamIface, mtu);
     }
 
     @Test
@@ -195,13 +212,13 @@
 
         mEm.setIncludeTestInterfaces(true);
 
-        mTestIface = createTestInterface();
+        mDownstreamIface = createTestInterface();
 
         final String iface = futureIface.get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
         assertEquals("TetheredInterfaceCallback for unexpected interface",
-                mTestIface.getInterfaceName(), iface);
+                mDownstreamIface.getInterfaceName(), iface);
 
-        checkVirtualEthernet(mTestIface, getMTU(mTestIface));
+        checkVirtualEthernet(mDownstreamIface, getMTU(mDownstreamIface));
     }
 
     @Test
@@ -210,11 +227,11 @@
 
         mEm.setIncludeTestInterfaces(true);
 
-        mTestIface = createTestInterface();
+        mDownstreamIface = createTestInterface();
 
         final String iface = mTetheredInterfaceRequester.getInterface();
         assertEquals("TetheredInterfaceCallback for unexpected interface",
-                mTestIface.getInterfaceName(), iface);
+                mDownstreamIface.getInterfaceName(), iface);
 
         assertInvalidStaticIpv4Request(iface, null, null);
         assertInvalidStaticIpv4Request(iface, "2001:db8::1/64", "2001:db8:2::/64");
@@ -235,8 +252,8 @@
         byte[] client1 = MacAddress.fromString("1:2:3:4:5:6").toByteArray();
         byte[] client2 = MacAddress.fromString("a:b:c:d:e:f").toByteArray();
 
-        FileDescriptor fd = mTestIface.getFileDescriptor().getFileDescriptor();
-        mTapPacketReader = makePacketReader(fd, getMTU(mTestIface));
+        FileDescriptor fd = mDownstreamIface.getFileDescriptor().getFileDescriptor();
+        mTapPacketReader = makePacketReader(fd, getMTU(mDownstreamIface));
         DhcpResults dhcpResults = runDhcp(fd, client1);
         assertEquals(new LinkAddress(clientAddr), dhcpResults.ipAddress);
 
@@ -301,11 +318,11 @@
 
         mEm.setIncludeTestInterfaces(true);
 
-        mTestIface = createTestInterface();
+        mDownstreamIface = createTestInterface();
 
         final String iface = mTetheredInterfaceRequester.getInterface();
         assertEquals("TetheredInterfaceCallback for unexpected interface",
-                mTestIface.getInterfaceName(), iface);
+                mDownstreamIface.getInterfaceName(), iface);
 
         final TetheringRequest request = new TetheringRequest.Builder(TETHERING_ETHERNET)
                 .setConnectivityScope(CONNECTIVITY_SCOPE_LOCAL).build();
@@ -316,8 +333,7 @@
         // does not have an IP address, and unprivileged apps cannot see interfaces without IP
         // addresses. This shouldn't be flaky because the TAP interface will buffer all packets even
         // before the reader is started.
-        FileDescriptor fd = mTestIface.getFileDescriptor().getFileDescriptor();
-        mTapPacketReader = makePacketReader(fd, getMTU(mTestIface));
+        mTapPacketReader = makePacketReader(mDownstreamIface);
 
         expectRouterAdvertisement(mTapPacketReader, iface, 2000 /* timeoutMs */);
         expectLocalOnlyAddresses(iface);
@@ -354,12 +370,14 @@
         private final CountDownLatch mLocalOnlyStartedLatch = new CountDownLatch(1);
         private final CountDownLatch mLocalOnlyStoppedLatch = new CountDownLatch(1);
         private final CountDownLatch mClientConnectedLatch = new CountDownLatch(1);
+        private final CountDownLatch mUpstreamConnectedLatch = new CountDownLatch(1);
         private final TetheringInterface mIface;
 
         private volatile boolean mInterfaceWasTethered = false;
         private volatile boolean mInterfaceWasLocalOnly = false;
         private volatile boolean mUnregistered = false;
         private volatile Collection<TetheredClient> mClients = null;
+        private volatile Network mUpstream = null;
 
         MyTetheringEventCallback(TetheringManager tm, String iface) {
             mTm = tm;
@@ -465,6 +483,22 @@
                     mClientConnectedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
             return mClients;
         }
+
+        @Override
+        public void onUpstreamChanged(Network network) {
+            // Ignore stale callbacks registered by previous test cases.
+            if (mUnregistered) return;
+
+            Log.d(TAG, "Got upstream changed: " + network);
+            mUpstream = network;
+            if (mUpstream != null) mUpstreamConnectedLatch.countDown();
+        }
+
+        public Network awaitFirstUpstreamConnected() throws Exception {
+            assertTrue("Did not receive upstream connected callback after " + TIMEOUT_MS + "ms",
+                    mUpstreamConnectedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+            return mUpstream;
+        }
     }
 
     private MyTetheringEventCallback enableEthernetTethering(String iface,
@@ -508,6 +542,11 @@
         return nif.getMTU();
     }
 
+    private TapPacketReader makePacketReader(final TestNetworkInterface iface) throws Exception {
+        FileDescriptor fd = iface.getFileDescriptor().getFileDescriptor();
+        return makePacketReader(fd, getMTU(iface));
+    }
+
     private TapPacketReader makePacketReader(FileDescriptor fd, int mtu) {
         final TapPacketReader reader = new TapPacketReader(mHandler, fd, mtu);
         mHandler.post(() -> reader.start());
@@ -701,10 +740,45 @@
     }
 
     private void maybeDeleteTestInterface() throws Exception {
-        if (mTestIface != null) {
-            mTestIface.getFileDescriptor().close();
-            Log.d(TAG, "Deleted test interface " + mTestIface.getInterfaceName());
-            mTestIface = null;
+        if (mDownstreamIface != null) {
+            mDownstreamIface.getFileDescriptor().close();
+            Log.d(TAG, "Deleted test interface " + mDownstreamIface.getInterfaceName());
+            mDownstreamIface = null;
         }
     }
+
+    private TestNetworkTracker createTestUpstream(final List<LinkAddress> addresses)
+            throws Exception {
+        mTm.setPreferTestNetworks(true);
+
+        return initTestNetwork(mContext, addresses, TIMEOUT_MS);
+    }
+
+    @Test
+    public void testTestNetworkUpstream() throws Exception {
+        assumeFalse(mEm.isAvailable());
+
+        // MyTetheringEventCallback currently only support await first available upstream. Tethering
+        // may select internet network as upstream if test network is not available and not be
+        // preferred yet. Create test upstream network before enable tethering.
+        mUpstreamTracker = createTestUpstream(toList(TEST_IP4_ADDR, TEST_IP6_ADDR));
+
+        mDownstreamIface = createTestInterface();
+        mEm.setIncludeTestInterfaces(true);
+
+        final String iface = mTetheredInterfaceRequester.getInterface();
+        assertEquals("TetheredInterfaceCallback for unexpected interface",
+                mDownstreamIface.getInterfaceName(), iface);
+
+        mTetheringEventCallback = enableEthernetTethering(mDownstreamIface.getInterfaceName());
+        assertEquals("onUpstreamChanged for unexpected network", mUpstreamTracker.getNetwork(),
+                mTetheringEventCallback.awaitFirstUpstreamConnected());
+
+        mTapPacketReader = makePacketReader(mDownstreamIface);
+        // TODO: do basic forwarding test here.
+    }
+
+    private <T> List<T> toList(T... array) {
+        return Arrays.asList(array);
+    }
 }