Send GARP and unsolicited multicast NA after L2 roaming. (8a0b767a) · Commits · e / os / android_packages_modules_NetworkStack

src/android/net/ip/IpClient.java

+81 −25

Original line number	Diff line number	Diff line
		@@ -18,13 +18,18 @@ package android.net.ip;

		import static android.net.RouteInfo.RTN_UNICAST;
		import static android.net.dhcp.DhcpResultsParcelableUtil.toStableParcelable;
		import static android.net.util.NetworkStackUtils.IPCLIENT_GARP_NA_ROAMING_VERSION;
		import static android.net.util.NetworkStackUtils.IPCLIENT_GRATUITOUS_NA_VERSION;
		import static android.net.util.SocketUtils.makePacketSocketAddress;
		import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
		import static android.system.OsConstants.AF_PACKET;
		import static android.system.OsConstants.ETH_P_ARP;
		import static android.system.OsConstants.ETH_P_IPV6;
		import static android.system.OsConstants.SOCK_NONBLOCK;
		import static android.system.OsConstants.SOCK_RAW;

		import static com.android.net.module.util.NetworkStackConstants.ARP_REPLY;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_BROADCAST;
		import static com.android.net.module.util.NetworkStackConstants.IPV6_ADDR_ALL_ROUTERS_MULTICAST;
		import static com.android.net.module.util.NetworkStackConstants.VENDOR_SPECIFIC_IE_ID;
		import static com.android.server.util.PermissionUtil.enforceNetworkStackCallingPermission;
		@@ -91,6 +96,7 @@ import com.android.networkstack.apishim.NetworkInformationShimImpl;
		import com.android.networkstack.apishim.SocketUtilsShimImpl;
		import com.android.networkstack.apishim.common.NetworkInformationShim;
		import com.android.networkstack.apishim.common.ShimUtils;
		import com.android.networkstack.arp.ArpPacket;
		import com.android.networkstack.metrics.IpProvisioningMetrics;
		import com.android.networkstack.packets.NeighborAdvertisement;
		import com.android.server.NetworkObserverRegistry;
		@@ -98,6 +104,7 @@ import com.android.server.NetworkStackService.NetworkStackServiceManager;

		import java.io.FileDescriptor;
		import java.io.PrintWriter;
		import java.net.Inet4Address;
		import java.net.Inet6Address;
		import java.net.InetAddress;
		import java.net.MalformedURLException;
		@@ -839,6 +846,11 @@ public class IpClient extends StateMachine {
		false /* defaultEnabled */);
		}

		private boolean isGratuitousArpNaRoamingEnabled() {
		return mDependencies.isFeatureEnabled(mContext, IPCLIENT_GARP_NA_ROAMING_VERSION,
		false /* defaultEnabled */);
		}

		@Override
		protected void onQuitting() {
		mCallback.onQuit();
		@@ -1423,30 +1435,47 @@ public class IpClient extends StateMachine {
		}
		}

		private void sendGratuitousNA(final Inet6Address srcIp, final Inet6Address target) {
		final int flags = 0; // R=0, S=0, O=0
		final Inet6Address dstIp = IPV6_ADDR_ALL_ROUTERS_MULTICAST;
		// Ethernet multicast destination address: 33:33:00:00:00:02.
		final MacAddress dstMac = NetworkStackUtils.ipv6MulticastToEthernetMulticast(dstIp);
		final ByteBuffer packet = NeighborAdvertisement.build(mInterfaceParams.macAddr, dstMac,
		srcIp, dstIp, flags, target);
		private void transmitPacket(final ByteBuffer packet, final SocketAddress sockAddress,
		final String msg) {
		FileDescriptor sock = null;
		try {
		sock = Os.socket(AF_PACKET, SOCK_RAW \| SOCK_NONBLOCK, 0 /* protocol */);
		final SocketAddress sockAddress =
		SocketUtilsShimImpl.newInstance().makePacketSocketAddress(ETH_P_IPV6,
		mInterfaceParams.index, dstMac.toByteArray());
		Os.sendto(sock, packet.array(), 0 /* byteOffset /, packet.limit() / byteCount */,
		0 /* flags */, sockAddress);
		} catch (SocketException \| ErrnoException e) {
		logError("Fail to send Gratuitous Neighbor Advertisement", e);
		logError(msg, e);
		} finally {
		NetworkStackUtils.closeSocketQuietly(sock);
		}
		}

		private Inet6Address getIpv6LinkLocalAddress(final LinkProperties newLp) {
		Inet6Address src = null;
		private void sendGratuitousNA(final Inet6Address srcIp, final Inet6Address targetIp) {
		final int flags = 0; // R=0, S=0, O=0
		final Inet6Address dstIp = IPV6_ADDR_ALL_ROUTERS_MULTICAST;
		// Ethernet multicast destination address: 33:33:00:00:00:02.
		final MacAddress dstMac = NetworkStackUtils.ipv6MulticastToEthernetMulticast(dstIp);
		final ByteBuffer packet = NeighborAdvertisement.build(mInterfaceParams.macAddr, dstMac,
		srcIp, dstIp, flags, targetIp);
		final SocketAddress sockAddress =
		SocketUtilsShimImpl.newInstance().makePacketSocketAddress(ETH_P_IPV6,
		mInterfaceParams.index, dstMac.toByteArray());

		transmitPacket(packet, sockAddress, "Failed to send Gratuitous Neighbor Advertisement");
		}

		private void sendGratuitousARP(final Inet4Address srcIp) {
		final ByteBuffer packet = ArpPacket.buildArpPacket(ETHER_BROADCAST /* dstMac */,
		mInterfaceParams.macAddr.toByteArray() /* srcMac */,
		srcIp.getAddress() /* targetIp */,
		ETHER_BROADCAST /* targetHwAddress */,
		srcIp.getAddress() /* senderIp */, (short) ARP_REPLY);
		final SocketAddress sockAddress =
		makePacketSocketAddress(ETH_P_ARP, mInterfaceParams.index);

		transmitPacket(packet, sockAddress, "Failed to send GARP");
		}

		private static Inet6Address getIpv6LinkLocalAddress(final LinkProperties newLp) {
		for (LinkAddress la : newLp.getLinkAddresses()) {
		if (!la.isIpv6()) continue;
		final Inet6Address ip = (Inet6Address) la.getAddress();
		@@ -1455,22 +1484,40 @@ public class IpClient extends StateMachine {
		return null;
		}

		private void maybeSendGratuitousNAs(final LinkProperties newLp) {
		if (!newLp.hasGlobalIpv6Address() \|\| !isGratuitousNaEnabled()) return;
		private void maybeSendGratuitousNAs(final LinkProperties lp, boolean afterRoaming) {
		if (!lp.hasGlobalIpv6Address()) return;

		final Inet6Address src = getIpv6LinkLocalAddress(newLp);
		if (src == null) return;
		for (LinkAddress la : newLp.getLinkAddresses()) {
		final Inet6Address srcIp = getIpv6LinkLocalAddress(lp);
		if (srcIp == null) return;

		// TODO: add experiment with sending only one gratuitous NA packet instead of one
		// packet per address.
		for (LinkAddress la : lp.getLinkAddresses()) {
		if (!la.isIpv6() \|\| !la.isGlobalPreferred()) continue;
		final Inet6Address targetIp = (Inet6Address) la.getAddress();
		// Already sent gratuitous NA with this target global IPv6 address.
		if (mGratuitousNaTargetAddresses.contains(targetIp)) continue;
		// Already sent gratuitous NA with this target global IPv6 address. But for
		// the L2 roaming case, device should always (re)transmit Gratuitous NA for
		// each IPv6 global unicast address respectively after roaming.
		if (!afterRoaming && mGratuitousNaTargetAddresses.contains(targetIp)) continue;
		if (DBG) {
		Log.d(mTag, "send Gratuitous NA from " + src + ", target Address is "
		+ targetIp);
		mLog.log("send Gratuitous NA from " + srcIp.getHostAddress() + " for "
		+ targetIp.getHostAddress() + (afterRoaming ? " after roaming" : ""));
		}
		sendGratuitousNA(srcIp, targetIp);
		if (!afterRoaming) mGratuitousNaTargetAddresses.add(targetIp);
		}
		}

		private void maybeSendGratuitousARP(final LinkProperties lp) {
		for (LinkAddress address : lp.getLinkAddresses()) {
		if (address.getAddress() instanceof Inet4Address) {
		final Inet4Address srcIp = (Inet4Address) address.getAddress();
		if (DBG) {
		mLog.log("send GARP for " + srcIp.getHostAddress() + " HW address: "
		+ mInterfaceParams.macAddr);
		}
		sendGratuitousARP(srcIp);
		}
		sendGratuitousNA(src, targetIp);
		mGratuitousNaTargetAddresses.add(targetIp);
		}
		}

		@@ -1484,7 +1531,9 @@ public class IpClient extends StateMachine {
		// Check if new assigned IPv6 GUA is available in the LinkProperties now. If so, initiate
		// gratuitous multicast unsolicited Neighbor Advertisements as soon as possible to inform
		// first-hop routers that the new GUA host is goning to use.
		maybeSendGratuitousNAs(newLp);
		if (isGratuitousNaEnabled()) {
		maybeSendGratuitousNAs(newLp, false /* isGratuitousNaAfterRoaming */);
		}

		// Either success IPv4 or IPv6 provisioning triggers new LinkProperties update,
		// wait for the provisioning completion and record the latency.
		@@ -1741,6 +1790,13 @@ public class IpClient extends StateMachine {
		// If the BSSID has not changed, there is nothing to do.
		if (info.bssid.equals(mCurrentBssid)) return;

		// Before trigger probing to the interesting neighbors, send Gratuitous ARP
		// and Neighbor Advertisment in advance to propgate host's IPv4/v6 addresses.
		if (isGratuitousArpNaRoamingEnabled()) {
		maybeSendGratuitousARP(mLinkProperties);
		maybeSendGratuitousNAs(mLinkProperties, true /* isGratuitousNaAfterRoaming */);
		}

		if (mIpReachabilityMonitor != null) {
		mIpReachabilityMonitor.probeAll();
		}

src/android/net/util/NetworkStackUtils.java

+7 −0

Original line number	Diff line number	Diff line
		@@ -242,6 +242,13 @@ public class NetworkStackUtils {
		*/
		public static final String IPCLIENT_GRATUITOUS_NA_VERSION = "ipclient_gratuitous_na_version";

		/**
		* Experiment flag to enable sending Gratuitous APR and Gratuitous Neighbor Advertisement for
		* all assigned IPv4 and IPv6 GUAs after completing L2 roaming.
		*/
		public static final String IPCLIENT_GARP_NA_ROAMING_VERSION =
		"ipclient_garp_na_roaming_version";

		static {
		System.loadLibrary("networkstackutilsjni");
		}

tests/integration/src/android/net/ip/IpClientIntegrationTestCommon.java

+146 −25

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@ import static com.android.net.module.util.Inet4AddressUtils.getPrefixMaskAsInet4
		import static com.android.net.module.util.NetworkStackConstants.ARP_REPLY;
		import static com.android.net.module.util.NetworkStackConstants.ARP_REQUEST;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_ADDR_LEN;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_BROADCAST;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_HEADER_LEN;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_OFFSET;
		import static com.android.net.module.util.NetworkStackConstants.ICMPV6_NEIGHBOR_ADVERTISEMENT;
		@@ -1121,6 +1122,14 @@ public abstract class IpClientIntegrationTestCommon {
		assertEquals(packet.senderIp, CLIENT_ADDR);
		}

		private void assertGratuitousARP(final ArpPacket packet) {
		assertEquals(packet.opCode, ARP_REPLY);
		assertEquals(packet.senderIp, CLIENT_ADDR);
		assertEquals(packet.targetIp, CLIENT_ADDR);
		assertTrue(Arrays.equals(packet.senderHwAddress.toByteArray(), mClientMac));
		assertTrue(Arrays.equals(packet.targetHwAddress.toByteArray(), ETHER_BROADCAST));
		}

		private void doIpAddressConflictDetectionTest(final boolean causeIpAddressConflict,
		final boolean shouldReplyRapidCommitAck, final boolean isDhcpIpConflictDetectEnabled,
		final boolean shouldResponseArpReply) throws Exception {
		@@ -1537,6 +1546,16 @@ public abstract class IpClientIntegrationTestCommon {
		return addr.isGlobalPreferred() && hasFlag(addr, flag);
		}

		private LinkProperties doIpv6OnlyProvisioning() throws Exception {
		final InOrder inOrder = inOrder(mCb);
		final String dnsServer = "2001:4860:4860::64";
		final ByteBuffer pio = buildPioOption(3600, 1800, "2001:db8:1::/64");
		final ByteBuffer rdnss = buildRdnssOption(3600, dnsServer);
		final ByteBuffer ra = buildRaPacket(pio, rdnss);

		return doIpv6OnlyProvisioning(inOrder, ra);
		}

		private LinkProperties doIpv6OnlyProvisioning(InOrder inOrder, ByteBuffer ra) throws Exception {
		waitForRouterSolicitation();
		mPacketReader.sendResponse(ra);
		@@ -2234,6 +2253,14 @@ public abstract class IpClientIntegrationTestCommon {
		true /* expectMetered */);
		}

		private void forceLayer2Roaming() throws Exception {
		final Layer2InformationParcelable roamingInfo = new Layer2InformationParcelable();
		roamingInfo.bssid = MacAddress.fromString(TEST_DHCP_ROAM_BSSID);
		roamingInfo.l2Key = TEST_DHCP_ROAM_L2KEY;
		roamingInfo.cluster = TEST_DHCP_ROAM_CLUSTER;
		mIIpClient.updateLayer2Information(roamingInfo);
		}

		private void doDhcpRoamingTest(final boolean hasMismatchedIpAddress, final String displayName,
		final String ssid, final String bssid, final boolean expectRoaming) throws Exception {
		long currentTime = System.currentTimeMillis();
		@@ -2260,11 +2287,7 @@ public abstract class IpClientIntegrationTestCommon {
		assertIpMemoryStoreNetworkAttributes(TEST_LEASE_DURATION_S, currentTime, TEST_DEFAULT_MTU);

		// simulate the roaming by updating bssid.
		final Layer2InformationParcelable roamingInfo = new Layer2InformationParcelable();
		roamingInfo.bssid = MacAddress.fromString(TEST_DHCP_ROAM_BSSID);
		roamingInfo.l2Key = TEST_DHCP_ROAM_L2KEY;
		roamingInfo.cluster = TEST_DHCP_ROAM_CLUSTER;
		mIpc.updateLayer2Information(roamingInfo);
		forceLayer2Roaming();

		currentTime = System.currentTimeMillis();
		reset(mIpMemoryStore);
		@@ -2338,18 +2361,7 @@ public abstract class IpClientIntegrationTestCommon {
		TEST_DHCP_ROAM_SSID, TEST_DEFAULT_BSSID, true /* expectRoaming */);
		}

		private void doDualStackProvisioning() throws Exception {
		when(mCm.shouldAvoidBadWifi()).thenReturn(true);

		final ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.build();
		// Enable rapid commit to accelerate DHCP handshake to shorten test duration,
		// not strictly necessary.
		setDhcpFeatures(false /* isDhcpLeaseCacheEnabled /, true / isRapidCommitEnabled */,
		false /* isDhcpIpConflictDetectEnabled /, false / isIPv6OnlyPreferredEnabled */);
		mIpc.startProvisioning(config);

		private void performDualStackProvisioning() throws Exception {
		final InOrder inOrder = inOrder(mCb);
		final CompletableFuture<LinkProperties> lpFuture = new CompletableFuture<>();
		final String dnsServer = "2001:4860:4860::64";
		@@ -2376,6 +2388,21 @@ public abstract class IpClientIntegrationTestCommon {
		reset(mCb);
		}

		private void doDualStackProvisioning() throws Exception {
		when(mCm.shouldAvoidBadWifi()).thenReturn(true);

		final ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.build();
		// Enable rapid commit to accelerate DHCP handshake to shorten test duration,
		// not strictly necessary.
		setDhcpFeatures(false /* isDhcpLeaseCacheEnabled /, true / isRapidCommitEnabled */,
		false /* isDhcpIpConflictDetectEnabled /, false / isIPv6OnlyPreferredEnabled */);
		mIpc.startProvisioning(config);

		performDualStackProvisioning();
		}

		@Test @SignatureRequiredTest(reason = "TODO: evaluate whether signature perms are required")
		public void testIgnoreIpv6ProvisioningLoss() throws Exception {
		doDualStackProvisioning();
		@@ -2796,7 +2823,7 @@ public abstract class IpClientIntegrationTestCommon {
		}

		@Test
		public void testGratuitousNa() throws Exception {
		public void testGratuitousNaForNewGlobalUnicastAddresses() throws Exception {
		final ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.withoutIPv4()
		@@ -2807,13 +2834,7 @@ public abstract class IpClientIntegrationTestCommon {
		assertTrue(isFeatureEnabled(NetworkStackUtils.IPCLIENT_GRATUITOUS_NA_VERSION, false));
		startIpClientProvisioning(config);

		final InOrder inOrder = inOrder(mCb);
		final String dnsServer = "2001:4860:4860::64";
		final ByteBuffer pio = buildPioOption(3600, 1800, "2001:db8:1::/64");
		final ByteBuffer rdnss = buildRdnssOption(3600, dnsServer);
		final ByteBuffer ra = buildRaPacket(pio, rdnss);

		doIpv6OnlyProvisioning(inOrder, ra);
		doIpv6OnlyProvisioning();

		final List<NeighborAdvertisement> naList = new ArrayList<>();
		NeighborAdvertisement packet;
		@@ -2823,4 +2844,104 @@ public abstract class IpClientIntegrationTestCommon {
		}
		assertEquals(2, naList.size()); // privacy address and stable privacy address
		}

		private void startGratuitousArpAndNaAfterRoamingTest(boolean isGratuitousArpNaRoamingEnabled,
		boolean hasIpv4, boolean hasIpv6) throws Exception {
		final ScanResultInfo scanResultInfo =
		makeScanResultInfo(TEST_DEFAULT_SSID, TEST_DEFAULT_BSSID);
		final ProvisioningConfiguration.Builder prov = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.withScanResultInfo(scanResultInfo)
		.withDisplayName("ssid");
		if (!hasIpv4) prov.withoutIPv4();
		if (!hasIpv6) prov.withoutIPv6();

		// Enable rapid commit to accelerate DHCP handshake to shorten test duration,
		// not strictly necessary.
		setDhcpFeatures(false /* isDhcpLeaseCacheEnabled /, true / isRapidCommitEnabled */,
		false /* isDhcpIpConflictDetectEnabled /, false / isIPv6OnlyPreferredEnabled */);
		if (isGratuitousArpNaRoamingEnabled) {
		setFeatureEnabled(NetworkStackUtils.IPCLIENT_GARP_NA_ROAMING_VERSION, true);
		assertTrue(isFeatureEnabled(NetworkStackUtils.IPCLIENT_GARP_NA_ROAMING_VERSION, false));
		}
		startIpClientProvisioning(prov.build());
		}

		private void waitForGratuitousArpAndNaPacket(final List<ArpPacket> arpList,
		final List<NeighborAdvertisement> naList) throws Exception {
		NeighborAdvertisement na;
		ArpPacket garp;
		do {
		na = getNextNeighborAdvertisement();
		if (na != null) {
		assertGratuitousNa(na);
		naList.add(na);
		}
		garp = getNextArpPacket(TEST_TIMEOUT_MS);
		if (garp != null) {
		assertGratuitousARP(garp);
		arpList.add(garp);
		}
		} while (na != null \|\| garp != null);
		}

		@Test
		public void testGratuitousArpAndNaAfterRoaming() throws Exception {
		startGratuitousArpAndNaAfterRoamingTest(true /* isGratuitousArpNaRoamingEnabled */,
		true /* hasIpv4 /, true / hasIpv6 */);
		performDualStackProvisioning();
		forceLayer2Roaming();

		final List<ArpPacket> arpList = new ArrayList<>();
		final List<NeighborAdvertisement> naList = new ArrayList<>();
		waitForGratuitousArpAndNaPacket(arpList, naList);
		assertEquals(2, naList.size()); // privacy address and stable privacy address
		assertEquals(1, arpList.size()); // IPv4 address
		}

		@Test
		public void testGratuitousArpAndNaAfterRoaming_disableExpFlag() throws Exception {
		startGratuitousArpAndNaAfterRoamingTest(false /* isGratuitousArpNaRoamingEnabled */,
		true /* hasIpv6 /, true / hasIpv6 */);
		performDualStackProvisioning();
		forceLayer2Roaming();

		final List<ArpPacket> arpList = new ArrayList<>();
		final List<NeighborAdvertisement> naList = new ArrayList<>();
		waitForGratuitousArpAndNaPacket(arpList, naList);
		assertEquals(0, naList.size());
		assertEquals(0, arpList.size());
		}

		@Test
		public void testGratuitousArpAndNaAfterRoaming_IPv6OnlyNetwork() throws Exception {
		startGratuitousArpAndNaAfterRoamingTest(true /* isGratuitousArpNaRoamingEnabled */,
		false /* hasIpv4 /, true / hasIpv6 */);
		doIpv6OnlyProvisioning();
		forceLayer2Roaming();

		final List<ArpPacket> arpList = new ArrayList<>();
		final List<NeighborAdvertisement> naList = new ArrayList<>();
		waitForGratuitousArpAndNaPacket(arpList, naList);
		assertEquals(2, naList.size());
		assertEquals(0, arpList.size());
		}

		@Test
		public void testGratuitousArpAndNaAfterRoaming_IPv4OnlyNetwork() throws Exception {
		startGratuitousArpAndNaAfterRoamingTest(true /* isGratuitousArpNaRoamingEnabled */,
		true /* hasIpv4 /, false / hasIpv6 */);

		// Start IPv4 provisioning and wait until entire provisioning completes.
		handleDhcpPackets(true /* isSuccessLease */, TEST_LEASE_DURATION_S,
		true /* shouldReplyRapidCommitAck /, TEST_DEFAULT_MTU, null / serverSentUrl */);
		verifyIPv4OnlyProvisioningSuccess(Collections.singletonList(CLIENT_ADDR));
		forceLayer2Roaming();

		final List<ArpPacket> arpList = new ArrayList<>();
		final List<NeighborAdvertisement> naList = new ArrayList<>();
		waitForGratuitousArpAndNaPacket(arpList, naList);
		assertEquals(0, naList.size());
		assertEquals(1, arpList.size());
		}
		}