Add an Ethernet tethering test.
This test uses EthernetManager's ability to use test network
interfaces to test tethering. This provides a fairly realistic
integration test for Tethering and its callbacks, IpServer and
DhcpServer, and so on.
It is in a new integration/ directory under Tethering because I
didn't really know where to put it. It's fast enough to run in
presubmit, but it didn't seem to be appropriate to call it a
unit test, and in the future we could also use this test to do
some limited testing of real Ethernet tethering as well.
Bug: 150644681
Test: atest TetheringIntegrationTests:EthernetTetheringTest --rerun-until-failure 100
Change-Id: Ifcda70b73848b1fd4c26b031e53f0a6500cc93d4
diff --git a/Tethering/tests/integration/Android.bp b/Tethering/tests/integration/Android.bp
new file mode 100644
index 0000000..1a1c30d
--- /dev/null
+++ b/Tethering/tests/integration/Android.bp
@@ -0,0 +1,42 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+android_test {
+ name: "TetheringIntegrationTests",
+ certificate: "platform",
+ platform_apis: true,
+ srcs: [
+ "src/**/*.java",
+ "src/**/*.kt",
+ ],
+ test_suites: [
+ "device-tests",
+ "mts",
+ ],
+ static_libs: [
+ "NetworkStackApiStableLib",
+ "androidx.test.rules",
+ "frameworks-base-testutils",
+ "mockito-target-extended-minus-junit4",
+ "net-tests-utils",
+ "testables",
+ ],
+ libs: [
+ "android.test.runner",
+ "android.test.base",
+ "android.test.mock",
+ ],
+}
diff --git a/Tethering/tests/integration/AndroidManifest.xml b/Tethering/tests/integration/AndroidManifest.xml
new file mode 100644
index 0000000..233ba40
--- /dev/null
+++ b/Tethering/tests/integration/AndroidManifest.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2020 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+ package="com.android.networkstack.tethering.tests.integration">
+
+ <uses-permission android:name="android.permission.INTERNET"/>
+ <uses-permission android:name="android.permission.TETHER_PRIVILEGED"/>
+
+ <application android:debuggable="true">
+ <uses-library android:name="android.test.runner" />
+ </application>
+ <instrumentation android:name="androidx.test.runner.AndroidJUnitRunner"
+ android:targetPackage="com.android.networkstack.tethering.tests.integration"
+ android:label="Tethering integration tests">
+ </instrumentation>
+</manifest>
diff --git a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
new file mode 100644
index 0000000..843a4f1
--- /dev/null
+++ b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
@@ -0,0 +1,460 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.Manifest.permission.MANAGE_TEST_NETWORKS;
+import static android.Manifest.permission.NETWORK_SETTINGS;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeFalse;
+import static org.junit.Assume.assumeTrue;
+
+import android.app.UiAutomation;
+import android.content.Context;
+import android.net.EthernetManager.TetheredInterfaceCallback;
+import android.net.EthernetManager.TetheredInterfaceRequest;
+import android.net.TetheringManager.StartTetheringCallback;
+import android.net.TetheringManager.TetheringEventCallback;
+import android.net.TetheringManager.TetheringRequest;
+import android.net.dhcp.DhcpAckPacket;
+import android.net.dhcp.DhcpOfferPacket;
+import android.net.dhcp.DhcpPacket;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.SystemClock;
+import android.system.Os;
+import android.util.Log;
+
+import androidx.test.InstrumentationRegistry;
+import androidx.test.filters.MediumTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.testutils.HandlerUtilsKt;
+import com.android.testutils.TapPacketReader;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.io.FileDescriptor;
+import java.net.Inet4Address;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.nio.ByteBuffer;
+import java.util.Collection;
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+@RunWith(AndroidJUnit4.class)
+@MediumTest
+public class EthernetTetheringTest {
+
+ private static final String TAG = EthernetTetheringTest.class.getSimpleName();
+ private static final int TIMEOUT_MS = 1000;
+ private static final int PACKET_READ_TIMEOUT_MS = 100;
+ private static final int DHCP_DISCOVER_ATTEMPTS = 10;
+ private static final byte[] DHCP_REQUESTED_PARAMS = new byte[] {
+ DhcpPacket.DHCP_SUBNET_MASK,
+ DhcpPacket.DHCP_ROUTER,
+ DhcpPacket.DHCP_DNS_SERVER,
+ DhcpPacket.DHCP_LEASE_TIME,
+ };
+ private static final String DHCP_HOSTNAME = "testhostname";
+
+ 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 HandlerThread mHandlerThread;
+ private Handler mHandler;
+ private TapPacketReader mTapPacketReader;
+
+ private TetheredInterfaceRequester mTetheredInterfaceRequester;
+ private MyTetheringEventCallback mTetheringEventCallback;
+
+ private UiAutomation mUiAutomation =
+ InstrumentationRegistry.getInstrumentation().getUiAutomation();
+
+ @Before
+ public void setUp() throws Exception {
+ mHandlerThread = new HandlerThread(getClass().getSimpleName());
+ mHandlerThread.start();
+ mHandler = new Handler(mHandlerThread.getLooper());
+ mTetheredInterfaceRequester = new TetheredInterfaceRequester(mHandler, mEm);
+ // Needed to create a TestNetworkInterface, to call requestTetheredInterface, and to receive
+ // tethered client callbacks.
+ mUiAutomation.adoptShellPermissionIdentity(MANAGE_TEST_NETWORKS, NETWORK_SETTINGS);
+ }
+
+ private void cleanUp() throws Exception {
+ mTm.stopTethering(TetheringManager.TETHERING_ETHERNET);
+ if (mTetheringEventCallback != null) {
+ mTetheringEventCallback.awaitInterfaceUntethered();
+ mTetheringEventCallback.unregister();
+ mTetheringEventCallback = null;
+ }
+ if (mTapPacketReader != null) {
+ TapPacketReader reader = mTapPacketReader;
+ mHandler.post(() -> reader.stop());
+ mTapPacketReader = null;
+ }
+ mHandlerThread.quitSafely();
+ mTetheredInterfaceRequester.release();
+ mEm.setIncludeTestInterfaces(false);
+ maybeDeleteTestInterface();
+ }
+
+ @After
+ public void tearDown() throws Exception {
+ try {
+ cleanUp();
+ } finally {
+ mUiAutomation.dropShellPermissionIdentity();
+ }
+ }
+
+ @Test
+ public void testVirtualEthernetAlreadyExists() throws Exception {
+ // This test requires manipulating packets. Skip if there is a physical Ethernet connected.
+ assumeFalse(mEm.isAvailable());
+
+ mTestIface = 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);
+
+ Log.d(TAG, "Including test interfaces");
+ mEm.setIncludeTestInterfaces(true);
+
+ Log.d(TAG, "Requesting tethered interface");
+ mTetheredInterfaceRequester.requestInterface();
+
+ final String iface = mTetheredInterfaceRequester.awaitRequestedInterface();
+ assertEquals("TetheredInterfaceCallback for unexpected interface",
+ mTestIface.getInterfaceName(), iface);
+
+ checkVirtualEthernet(mTestIface, mtu);
+ }
+
+ @Test
+ public void testVirtualEthernet() throws Exception {
+ // This test requires manipulating packets. Skip if there is a physical Ethernet connected.
+ assumeFalse(mEm.isAvailable());
+
+ Log.d(TAG, "Requesting tethered interface");
+ mTetheredInterfaceRequester.requestInterface();
+
+ mEm.setIncludeTestInterfaces(true);
+
+ mTestIface = createTestInterface();
+
+ final String iface = mTetheredInterfaceRequester.awaitRequestedInterface();
+ assertEquals("TetheredInterfaceCallback for unexpected interface",
+ mTestIface.getInterfaceName(), iface);
+
+ checkVirtualEthernet(mTestIface, getMTU(mTestIface));
+ }
+
+ @Test
+ public void testPhysicalEthernet() throws Exception {
+ assumeTrue(mEm.isAvailable());
+
+ // Get an interface to use.
+ mTetheredInterfaceRequester.requestInterface();
+ String iface = mTetheredInterfaceRequester.awaitRequestedInterface();
+
+ // Enable Ethernet tethering and check that it starts.
+ mTetheringEventCallback = enableEthernetTethering(iface);
+
+ // There is nothing more we can do on a physical interface without connecting an actual
+ // client, which is not possible in this test.
+ }
+
+ private static final class MyTetheringEventCallback implements TetheringEventCallback {
+ private final TetheringManager mTm;
+ private final CountDownLatch mTetheringStartedLatch = new CountDownLatch(1);
+ private final CountDownLatch mTetheringStoppedLatch = new CountDownLatch(1);
+ private final CountDownLatch mClientConnectedLatch = new CountDownLatch(1);
+ private final String mIface;
+
+ private volatile boolean mInterfaceWasTethered = false;
+ private volatile boolean mUnregistered = false;
+ private volatile Collection<TetheredClient> mClients = null;
+
+ MyTetheringEventCallback(TetheringManager tm, String iface) {
+ mTm = tm;
+ mIface = iface;
+ }
+
+ public void unregister() {
+ mTm.unregisterTetheringEventCallback(this);
+ mUnregistered = true;
+ }
+
+ @Override
+ public void onTetheredInterfacesChanged(List<String> interfaces) {
+ // Ignore stale callbacks registered by previous test cases.
+ if (mUnregistered) return;
+
+ final boolean wasTethered = mTetheringStartedLatch.getCount() == 0;
+ if (!mInterfaceWasTethered && (mIface == null || interfaces.contains(mIface))) {
+ // This interface is being tethered for the first time.
+ Log.d(TAG, "Tethering started: " + interfaces);
+ mInterfaceWasTethered = true;
+ mTetheringStartedLatch.countDown();
+ } else if (mInterfaceWasTethered && !interfaces.contains(mIface)) {
+ Log.d(TAG, "Tethering stopped: " + interfaces);
+ mTetheringStoppedLatch.countDown();
+ }
+ }
+
+ public void awaitInterfaceTethered() throws Exception {
+ assertTrue("Ethernet not tethered after " + TIMEOUT_MS + "ms",
+ mTetheringStartedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+ }
+
+ public void awaitInterfaceUntethered() throws Exception {
+ // Don't block teardown if the interface was never tethered.
+ // This is racy because the interface might become tethered right after this check, but
+ // that can only happen in tearDown if startTethering timed out, which likely means
+ // the test has already failed.
+ if (!mInterfaceWasTethered) return;
+
+ assertTrue(mIface + " not untethered after " + TIMEOUT_MS + "ms",
+ mTetheringStoppedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+ }
+
+ @Override
+ public void onError(String ifName, int error) {
+ // Ignore stale callbacks registered by previous test cases.
+ if (mUnregistered) return;
+
+ fail("TetheringEventCallback got error:" + error + " on iface " + ifName);
+ }
+
+ @Override
+ public void onClientsChanged(Collection<TetheredClient> clients) {
+ // Ignore stale callbacks registered by previous test cases.
+ if (mUnregistered) return;
+
+ Log.d(TAG, "Got clients changed: " + clients);
+ mClients = clients;
+ if (clients.size() > 0) {
+ mClientConnectedLatch.countDown();
+ }
+ }
+
+ public Collection<TetheredClient> awaitClientConnected() throws Exception {
+ assertTrue("Did not receive client connected callback after " + TIMEOUT_MS + "ms",
+ mClientConnectedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+ return mClients;
+ }
+ }
+
+ private MyTetheringEventCallback enableEthernetTethering(String iface) throws Exception {
+ MyTetheringEventCallback callback = new MyTetheringEventCallback(mTm, iface);
+ mTm.registerTetheringEventCallback(mHandler::post, callback);
+
+ StartTetheringCallback startTetheringCallback = new StartTetheringCallback() {
+ @Override
+ public void onTetheringFailed(int resultCode) {
+ fail("Unexpectedly got onTetheringFailed");
+ }
+ };
+ Log.d(TAG, "Starting Ethernet tethering");
+ mTm.startTethering(
+ new TetheringRequest.Builder(TetheringManager.TETHERING_ETHERNET).build(),
+ mHandler::post /* executor */, startTetheringCallback);
+ callback.awaitInterfaceTethered();
+ return callback;
+ }
+
+ private int getMTU(TestNetworkInterface iface) throws SocketException {
+ NetworkInterface nif = NetworkInterface.getByName(iface.getInterfaceName());
+ assertNotNull("Can't get NetworkInterface object for " + iface.getInterfaceName(), nif);
+ return nif.getMTU();
+ }
+
+ private void checkVirtualEthernet(TestNetworkInterface iface, int mtu) throws Exception {
+ FileDescriptor fd = iface.getFileDescriptor().getFileDescriptor();
+ mTapPacketReader = new TapPacketReader(mHandler, fd, mtu);
+ mHandler.post(() -> mTapPacketReader.start());
+ HandlerUtilsKt.waitForIdle(mHandler, TIMEOUT_MS);
+
+ mTetheringEventCallback = enableEthernetTethering(iface.getInterfaceName());
+ checkTetheredClientCallbacks(fd);
+ }
+
+ private void checkTetheredClientCallbacks(FileDescriptor fd) throws Exception {
+ // Create a fake client.
+ byte[] clientMacAddr = new byte[6];
+ new Random().nextBytes(clientMacAddr);
+
+ // We have to retransmit DHCP requests because IpServer declares itself to be ready before
+ // its DhcpServer is actually started. TODO: fix this race and remove this loop.
+ DhcpPacket offerPacket = null;
+ for (int i = 0; i < DHCP_DISCOVER_ATTEMPTS; i++) {
+ Log.d(TAG, "Sending DHCP discover");
+ sendDhcpDiscover(fd, clientMacAddr);
+ offerPacket = getNextDhcpPacket();
+ if (offerPacket instanceof DhcpOfferPacket) break;
+ }
+ assertTrue("No DHCPOFFER received on interface within timeout",
+ offerPacket instanceof DhcpOfferPacket);
+
+ sendDhcpRequest(fd, offerPacket, clientMacAddr);
+ DhcpPacket ackPacket = getNextDhcpPacket();
+ assertTrue("No DHCPACK received on interface within timeout",
+ ackPacket instanceof DhcpAckPacket);
+
+ final Collection<TetheredClient> clients = mTetheringEventCallback.awaitClientConnected();
+ assertEquals(1, clients.size());
+ final TetheredClient client = clients.iterator().next();
+
+ // Check the MAC address.
+ assertEquals(MacAddress.fromBytes(clientMacAddr), client.getMacAddress());
+ assertEquals(TetheringManager.TETHERING_ETHERNET, client.getTetheringType());
+
+ // Check the hostname.
+ assertEquals(1, client.getAddresses().size());
+ TetheredClient.AddressInfo info = client.getAddresses().get(0);
+ assertEquals(DHCP_HOSTNAME, info.getHostname());
+
+ // Check the address is the one that was handed out in the DHCP ACK.
+ DhcpResults dhcpResults = offerPacket.toDhcpResults();
+ assertLinkAddressMatches(dhcpResults.ipAddress, info.getAddress());
+
+ // Check that the lifetime is correct +/- 10s.
+ final long now = SystemClock.elapsedRealtime();
+ final long actualLeaseDuration = (info.getAddress().getExpirationTime() - now) / 1000;
+ final String msg = String.format("IP address should have lifetime of %d, got %d",
+ dhcpResults.leaseDuration, actualLeaseDuration);
+ assertTrue(msg, Math.abs(dhcpResults.leaseDuration - actualLeaseDuration) < 10);
+ }
+
+ private DhcpPacket getNextDhcpPacket() throws ParseException {
+ byte[] packet;
+ while ((packet = mTapPacketReader.popPacket(PACKET_READ_TIMEOUT_MS)) != null) {
+ try {
+ return DhcpPacket.decodeFullPacket(packet, packet.length, DhcpPacket.ENCAP_L2);
+ } catch (DhcpPacket.ParseException e) {
+ // Not a DHCP packet. Continue.
+ }
+ }
+ return null;
+ }
+
+ private static final class TetheredInterfaceRequester implements TetheredInterfaceCallback {
+ private final CountDownLatch mInterfaceAvailableLatch = new CountDownLatch(1);
+ private final Handler mHandler;
+ private final EthernetManager mEm;
+
+ private volatile TetheredInterfaceRequest mRequest;
+ private volatile String mIface;
+
+ TetheredInterfaceRequester(Handler handler, EthernetManager em) {
+ mHandler = handler;
+ mEm = em;
+ }
+
+ @Override
+ public void onAvailable(String iface) {
+ Log.d(TAG, "Ethernet interface available: " + iface);
+ mIface = iface;
+ mInterfaceAvailableLatch.countDown();
+ }
+ @Override
+ public void onUnavailable() {}
+
+ public void requestInterface() {
+ assertNull("BUG: more than one tethered interface request", mRequest);
+ mRequest = mEm.requestTetheredInterface(mHandler::post, this);
+ }
+
+ public String awaitRequestedInterface() throws InterruptedException {
+ assertTrue("No tethered interface available after " + TIMEOUT_MS + "ms",
+ mInterfaceAvailableLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+ return mIface;
+ }
+
+ public void release() {
+ if (mRequest != null) {
+ mRequest.release();
+ mRequest = null;
+ }
+ }
+ }
+
+ private void sendDhcpDiscover(FileDescriptor fd, byte[] macAddress) throws Exception {
+ ByteBuffer packet = DhcpPacket.buildDiscoverPacket(DhcpPacket.ENCAP_L2,
+ new Random().nextInt() /* transactionId */, (short) 0 /* secs */,
+ macAddress, false /* unicast */, DHCP_REQUESTED_PARAMS,
+ false /* rapid commit */, DHCP_HOSTNAME);
+ sendPacket(fd, packet);
+ }
+
+ private void sendDhcpRequest(FileDescriptor fd, DhcpPacket offerPacket, byte[] macAddress)
+ throws Exception {
+ DhcpResults results = offerPacket.toDhcpResults();
+ Inet4Address clientIp = (Inet4Address) results.ipAddress.getAddress();
+ Inet4Address serverIdentifier = results.serverAddress;
+ ByteBuffer packet = DhcpPacket.buildRequestPacket(DhcpPacket.ENCAP_L2,
+ 0 /* transactionId */, (short) 0 /* secs */, DhcpPacket.INADDR_ANY /* clientIp */,
+ false /* broadcast */, macAddress, clientIp /* requestedIpAddress */,
+ serverIdentifier, DHCP_REQUESTED_PARAMS, DHCP_HOSTNAME);
+ sendPacket(fd, packet);
+ }
+
+ private void sendPacket(FileDescriptor fd, ByteBuffer packet) throws Exception {
+ assertNotNull("Only tests on virtual interfaces can send packets", fd);
+ Os.write(fd, packet);
+ }
+
+ public void assertLinkAddressMatches(LinkAddress l1, LinkAddress l2) {
+ // Check all fields except the deprecation and expiry times.
+ String msg = String.format("LinkAddresses do not match. expected: %s actual: %s", l1, l2);
+ assertTrue(msg, l1.isSameAddressAs(l2));
+ assertEquals("LinkAddress flags do not match", l1.getFlags(), l2.getFlags());
+ assertEquals("LinkAddress scope does not match", l1.getScope(), l2.getScope());
+ }
+
+ private TestNetworkInterface createTestInterface() throws Exception {
+ TestNetworkManager tnm = mContext.getSystemService(TestNetworkManager.class);
+ TestNetworkInterface iface = tnm.createTapInterface();
+ Log.d(TAG, "Created test interface " + iface.getInterfaceName());
+ assertNotNull(NetworkInterface.getByName(iface.getInterfaceName()));
+ return iface;
+ }
+
+ private void maybeDeleteTestInterface() throws Exception {
+ if (mTestIface != null) {
+ mTestIface.getFileDescriptor().close();
+ Log.d(TAG, "Deleted test interface " + mTestIface.getInterfaceName());
+ mTestIface = null;
+ }
+ }
+}