Merge "Add tests for IPv4-only private DNS servers" (387a51ee) · Commits · e / os / android_packages_modules_NetworkStack

src/com/android/networkstack/util/DnsUtils.java

+3 −0

Original line number	Diff line number	Diff line
		@@ -47,6 +47,9 @@ import java.util.concurrent.TimeoutException;
		public class DnsUtils {
		// Decide what queries to make depending on what IP addresses are on the system.
		public static final int TYPE_ADDRCONFIG = -1;
		// A one time host name suffix of private dns probe.
		// q.v. system/netd/server/dns/DnsTlsTransport.cpp
		public static final String PRIVATE_DNS_PROBE_HOST_SUFFIX = "-dnsotls-ds.metric.gstatic.com";
		private static final String TAG = DnsUtils.class.getSimpleName();
		private static final boolean DBG = Log.isLoggable(TAG, Log.DEBUG);

src/com/android/server/connectivity/NetworkMonitor.java

+2 −3

Original line number	Diff line number	Diff line
		@@ -65,6 +65,7 @@ import static android.net.util.NetworkStackUtils.CAPTIVE_PORTAL_USE_HTTPS;
		import static android.net.util.NetworkStackUtils.NAMESPACE_CONNECTIVITY;
		import static android.net.util.NetworkStackUtils.isEmpty;

		import static com.android.networkstack.util.DnsUtils.PRIVATE_DNS_PROBE_HOST_SUFFIX;
		import static com.android.networkstack.util.DnsUtils.TYPE_ADDRCONFIG;

		import android.annotation.NonNull;
		@@ -1083,10 +1084,8 @@ public class NetworkMonitor extends StateMachine {
		}

		private boolean sendPrivateDnsProbe() {
		// q.v. system/netd/server/dns/DnsTlsTransport.cpp
		final String oneTimeHostnameSuffix = "-dnsotls-ds.metric.gstatic.com";
		final String host = UUID.randomUUID().toString().substring(0, 8)
		+ oneTimeHostnameSuffix;
		+ PRIVATE_DNS_PROBE_HOST_SUFFIX;
		final Stopwatch watch = new Stopwatch().start();
		boolean success = false;
		long time;

tests/unit/src/com/android/server/connectivity/NetworkMonitorTest.java

+115 −44

Original line number	Diff line number	Diff line
		@@ -17,6 +17,8 @@
		package com.android.server.connectivity;

		import static android.net.CaptivePortal.APP_RETURN_DISMISSED;
		import static android.net.DnsResolver.TYPE_A;
		import static android.net.DnsResolver.TYPE_AAAA;
		import static android.net.INetworkMonitor.NETWORK_VALIDATION_PROBE_DNS;
		import static android.net.INetworkMonitor.NETWORK_VALIDATION_PROBE_FALLBACK;
		import static android.net.INetworkMonitor.NETWORK_VALIDATION_PROBE_HTTP;
		@@ -34,6 +36,8 @@ import static android.net.util.NetworkStackUtils.CAPTIVE_PORTAL_FALLBACK_PROBE_S
		import static android.net.util.NetworkStackUtils.CAPTIVE_PORTAL_OTHER_FALLBACK_URLS;
		import static android.net.util.NetworkStackUtils.CAPTIVE_PORTAL_USE_HTTPS;

		import static com.android.networkstack.util.DnsUtils.PRIVATE_DNS_PROBE_HOST_SUFFIX;

		import static junit.framework.Assert.assertEquals;
		import static junit.framework.Assert.assertFalse;

		@@ -63,7 +67,6 @@ import android.content.res.Resources;
		import android.net.ConnectivityManager;
		import android.net.DnsResolver;
		import android.net.INetworkMonitorCallbacks;
		import android.net.InetAddresses;
		import android.net.LinkProperties;
		import android.net.Network;
		import android.net.NetworkCapabilities;
		@@ -89,6 +92,7 @@ import android.util.ArrayMap;
		import androidx.test.filters.SmallTest;
		import androidx.test.runner.AndroidJUnit4;

		import com.android.internal.util.CollectionUtils;
		import com.android.networkstack.R;
		import com.android.networkstack.metrics.DataStallDetectionStats;
		import com.android.networkstack.metrics.DataStallStatsUtils;
		@@ -112,6 +116,7 @@ import java.net.InetAddress;
		import java.net.URL;
		import java.net.UnknownHostException;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.HashSet;
		import java.util.List;
		import java.util.Random;
		@@ -196,7 +201,23 @@ public class NetworkMonitorTest {
		* Network#getAllByName and by DnsResolver#query.
		*/
		class FakeDns {
		private final ArrayMap<String, List<InetAddress>> mAnswers = new ArrayMap<>();
		/** Data class to record the Dns entry. */
		class DnsEntry {
		final String mHostname;
		final int mType;
		final List<InetAddress> mAddresses;
		DnsEntry(String host, int type, List<InetAddress> addr) {
		mHostname = host;
		mType = type;
		mAddresses = addr;
		}
		// Full match or partial match that target host contains the entry hostname to support
		// random private dns probe hostname.
		private boolean matches(String hostname, int type) {
		return hostname.endsWith(mHostname) && type == mType;
		}
		}
		private final ArrayList<DnsEntry> mAnswers = new ArrayList<DnsEntry>();
		private boolean mNonBypassPrivateDnsWorking = true;

		/** Whether DNS queries on mNonBypassPrivateDnsWorking should succeed. */
		@@ -209,41 +230,57 @@ public class NetworkMonitorTest {
		mAnswers.clear();
		}

		/** Returns the answer for a given name on the given mock network. */
		private synchronized List<InetAddress> getAnswer(Object mock, String hostname) {
		/** Returns the answer for a given name and type on the given mock network. */
		private synchronized List<InetAddress> getAnswer(Object mock, String hostname, int type) {
		if (mock == mNetwork && !mNonBypassPrivateDnsWorking) {
		return null;
		}
		if (mAnswers.containsKey(hostname)) {
		return mAnswers.get(hostname);
		}
		return mAnswers.get("*");

		DnsEntry answer = CollectionUtils.find(mAnswers, e -> e.matches(hostname, type));
		if (answer != null) return answer.mAddresses;
		else return null;
		}

		/** Sets the answer for a given name. */
		private synchronized void setAnswer(String hostname, String[] answer)
		/** Sets the answer for a given name and type. */
		private synchronized void setAnswer(String hostname, String[] answer, int type)
		throws UnknownHostException {
		if (answer == null) {
		mAnswers.remove(hostname);
		} else {
		List<InetAddress> answerList = new ArrayList<>();
		for (String addr : answer) {
		answerList.add(InetAddresses.parseNumericAddress(addr));
		}
		mAnswers.put(hostname, answerList);
		DnsEntry record = new DnsEntry(hostname, type, generateAnswer(answer));
		// Remove the existing one.
		mAnswers.removeIf(entry -> entry.matches(hostname, type));
		// Add or replace a new record.
		mAnswers.add(record);
		}

		private List<InetAddress> generateAnswer(String[] answer) {
		if (answer == null) return new ArrayList<>();
		return CollectionUtils.map(Arrays.asList(answer),
		addr -> InetAddress.parseNumericAddress(addr));
		}

		/** Simulates a getAllByName call for the specified name on the specified mock network. */
		private InetAddress[] getAllByName(Object mock, String hostname)
		throws UnknownHostException {
		List<InetAddress> answer = getAnswer(mock, hostname);
		List<InetAddress> answer = queryAllTypes(mock, hostname);
		if (answer == null \|\| answer.size() == 0) {
		throw new UnknownHostException(hostname);
		}
		return answer.toArray(new InetAddress[0]);
		}

		// Regardless of the type, depends on what the responses contained in the network.
		private List<InetAddress> queryAllTypes(Object mock, String hostname) {
		List<InetAddress> answer = new ArrayList<>();
		addAllIfNotNull(answer, getAnswer(mock, hostname, TYPE_A));
		addAllIfNotNull(answer, getAnswer(mock, hostname, TYPE_AAAA));
		return answer;
		}

		private void addAllIfNotNull(List<InetAddress> list, List<InetAddress> c) {
		if (c != null) {
		list.addAll(c);
		}
		}

		/** Starts mocking DNS queries. */
		private void startMocking() throws UnknownHostException {
		// Queries on mNetwork using getAllByName.
		@@ -254,24 +291,28 @@ public class NetworkMonitorTest {
		// Queries on mCleartextDnsNetwork using DnsResolver#query.
		doAnswer(invocation -> {
		return mockQuery(invocation, 1 /* posHostname /, 3 / posExecutor */,
		5 /* posCallback */);
		5 /* posCallback /, -1 / posType */);
		}).when(mDnsResolver).query(any(), any(), anyInt(), any(), any(), any());

		// Queries on mCleartextDnsNetwork using DnsResolver#query with QueryType.
		doAnswer(invocation -> {
		return mockQuery(invocation, 1 /* posHostname /, 4 / posExecutor */,
		6 /* posCallback */);
		6 /* posCallback /, 2 / posType */);
		}).when(mDnsResolver).query(any(), any(), anyInt(), anyInt(), any(), any(), any());
		}

		// Mocking queries on DnsResolver#query.
		private Answer mockQuery(InvocationOnMock invocation, int posHostname, int posExecutor,
		int posCallback) {
		int posCallback, int posType) {
		String hostname = (String) invocation.getArgument(posHostname);
		Executor executor = (Executor) invocation.getArgument(posExecutor);
		DnsResolver.Callback<List<InetAddress>> callback = invocation.getArgument(posCallback);
		List<InetAddress> answer;

		answer = posType != -1
		? getAnswer(invocation.getMock(), hostname, invocation.getArgument(posType)) :
		queryAllTypes(invocation.getMock(), hostname);

		List<InetAddress> answer = getAnswer(invocation.getMock(), hostname);
		if (answer != null && answer.size() > 0) {
		new Handler(Looper.getMainLooper()).post(() -> {
		executor.execute(() -> callback.onAnswer(answer, 0));
		@@ -341,7 +382,13 @@ public class NetworkMonitorTest {

		mFakeDns = new FakeDns();
		mFakeDns.startMocking();
		mFakeDns.setAnswer("*", new String[]{"2001:db8::1", "192.0.2.2"});
		// Set private dns suffix answer. sendPrivateDnsProbe() in NetworkMonitor send probe with
		// one time hostname. The hostname will be [random generated UUID] + HOST_SUFFIX differently
		// each time. That means the host answer cannot be pre-set into the answer list. Thus, set
		// the host suffix and use partial match in FakeDns to match the target host and reply the
		// intended answer.
		mFakeDns.setAnswer(PRIVATE_DNS_PROBE_HOST_SUFFIX, new String[]{"192.0.2.2"}, TYPE_A);
		mFakeDns.setAnswer(PRIVATE_DNS_PROBE_HOST_SUFFIX, new String[]{"2001:db8::1"}, TYPE_AAAA);

		when(mContext.registerReceiver(any(BroadcastReceiver.class), any())).then((invocation) -> {
		mRegisteredReceivers.add(invocation.getArgument(0));
		@@ -743,20 +790,39 @@ public class NetworkMonitorTest {
		public void testPrivateDnsSuccess() throws Exception {
		setStatus(mHttpsConnection, 204);
		setStatus(mHttpConnection, 204);
		mFakeDns.setAnswer("dns.google", new String[]{"2001:db8::53"});

		// Verify dns query only get v6 address.
		mFakeDns.setAnswer("dns6.google", new String[]{"2001:db8::53"}, TYPE_AAAA);
		WrappedNetworkMonitor wnm = makeNotMeteredNetworkMonitor();
		wnm.notifyPrivateDnsSettingsChanged(new PrivateDnsConfig("dns.google", new InetAddress[0]));
		wnm.notifyPrivateDnsSettingsChanged(new PrivateDnsConfig("dns6.google",
		new InetAddress[0]));
		wnm.notifyNetworkConnected(TEST_LINK_PROPERTIES, NOT_METERED_CAPABILITIES);
		verify(mCallbacks, timeout(HANDLER_TIMEOUT_MS).times(1))
		.notifyNetworkTested(eq(VALIDATION_RESULT_VALID \| NETWORK_VALIDATION_PROBE_PRIVDNS),
		eq(null));

		// Verify dns query only get v4 address.
		resetCallbacks();
		mFakeDns.setAnswer("dns4.google", new String[]{"192.0.2.1"}, TYPE_A);
		wnm.notifyPrivateDnsSettingsChanged(new PrivateDnsConfig("dns4.google",
		new InetAddress[0]));
		verify(mCallbacks, timeout(HANDLER_TIMEOUT_MS).times(1))
		.notifyNetworkTested(eq(VALIDATION_RESULT_VALID \| NETWORK_VALIDATION_PROBE_PRIVDNS),
		eq(null));

		// Verify dns query get both v4 and v6 address.
		resetCallbacks();
		mFakeDns.setAnswer("dns.google", new String[]{"2001:db8::54"}, TYPE_AAAA);
		mFakeDns.setAnswer("dns.google", new String[]{"192.0.2.3"}, TYPE_A);
		wnm.notifyPrivateDnsSettingsChanged(new PrivateDnsConfig("dns.google", new InetAddress[0]));
		verify(mCallbacks, timeout(HANDLER_TIMEOUT_MS).times(1))
		.notifyNetworkTested(eq(VALIDATION_RESULT_VALID \| NETWORK_VALIDATION_PROBE_PRIVDNS),
		eq(null));
		}

		@Test
		public void testPrivateDnsResolutionRetryUpdate() throws Exception {
		// Set a private DNS hostname that doesn't resolve and expect validation to fail.
		mFakeDns.setAnswer("dns.google", new String[0]);
		// Set no record in FakeDns and expect validation to fail.
		setStatus(mHttpsConnection, 204);
		setStatus(mHttpConnection, 204);

		@@ -770,7 +836,7 @@ public class NetworkMonitorTest {

		// Fix DNS and retry, expect validation to succeed.
		resetCallbacks();
		mFakeDns.setAnswer("dns.google", new String[]{"2001:db8::1"});
		mFakeDns.setAnswer("dns.google", new String[]{"2001:db8::1"}, TYPE_AAAA);

		wnm.forceReevaluation(Process.myUid());
		verify(mCallbacks, timeout(HANDLER_TIMEOUT_MS).atLeastOnce())
		@@ -779,7 +845,8 @@ public class NetworkMonitorTest {

		// Change configuration to an invalid DNS name, expect validation to fail.
		resetCallbacks();
		mFakeDns.setAnswer("dns.bad", new String[0]);
		mFakeDns.setAnswer("dns.bad", new String[0], TYPE_A);
		mFakeDns.setAnswer("dns.bad", new String[0], TYPE_AAAA);
		wnm.notifyPrivateDnsSettingsChanged(new PrivateDnsConfig("dns.bad", new InetAddress[0]));
		// Strict mode hostname resolve fail. Expect only notification for evaluation fail. No probe
		// notification.
		@@ -900,30 +967,34 @@ public class NetworkMonitorTest {
		public void testSendDnsProbeWithTimeout() throws Exception {
		WrappedNetworkMonitor wnm = makeNotMeteredNetworkMonitor();
		final int shortTimeoutMs = 200;

		// Clear the wildcard DNS response created in setUp.
		mFakeDns.setAnswer("*", null);

		// v6 only.
		String[] expected = new String[]{"2001:db8::"};
		mFakeDns.setAnswer("www.google.com", expected);
		mFakeDns.setAnswer("www.google.com", expected, TYPE_AAAA);
		InetAddress[] actual = wnm.sendDnsProbeWithTimeout("www.google.com", shortTimeoutMs);
		assertIpAddressArrayEquals(expected, actual);

		expected = new String[]{"2001:db8::", "192.0.2.1"};
		mFakeDns.setAnswer("www.googleapis.com", expected);
		// v4 only.
		expected = new String[]{"192.0.2.1"};
		mFakeDns.setAnswer("www.android.com", expected, TYPE_A);
		actual = wnm.sendDnsProbeWithTimeout("www.android.com", shortTimeoutMs);
		assertIpAddressArrayEquals(expected, actual);
		// Both v4 & v6.
		expected = new String[]{"192.0.2.1", "2001:db8::"};
		mFakeDns.setAnswer("www.googleapis.com", new String[]{"192.0.2.1"}, TYPE_A);
		mFakeDns.setAnswer("www.googleapis.com", new String[]{"2001:db8::"}, TYPE_AAAA);
		actual = wnm.sendDnsProbeWithTimeout("www.googleapis.com", shortTimeoutMs);
		assertIpAddressArrayEquals(expected, actual);

		mFakeDns.setAnswer("www.google.com", new String[0]);
		// Clear DNS response.
		mFakeDns.setAnswer("www.android.com", new String[0], TYPE_A);
		try {
		wnm.sendDnsProbeWithTimeout("www.google.com", shortTimeoutMs);
		actual = wnm.sendDnsProbeWithTimeout("www.android.com", shortTimeoutMs);
		fail("No DNS results, expected UnknownHostException");
		} catch (UnknownHostException e) {
		}

		mFakeDns.setAnswer("www.google.com", null);
		mFakeDns.setAnswer("www.android.com", null, TYPE_A);
		mFakeDns.setAnswer("www.android.com", null, TYPE_AAAA);
		try {
		wnm.sendDnsProbeWithTimeout("www.google.com", shortTimeoutMs);
		wnm.sendDnsProbeWithTimeout("www.android.com", shortTimeoutMs);
		fail("DNS query timed out, expected UnknownHostException");
		} catch (UnknownHostException e) {
		}