Merge "Support gratuitous unsolicited Neighbor Advertisement." (00197139) · Commits · e / os / android_packages_modules_NetworkStack

src/android/net/ip/IpClient.java

+103 −0

Original line number	Diff line number	Diff line
		@@ -18,8 +18,14 @@ 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_GRATUITOUS_NA_VERSION;
		import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
		import static android.system.OsConstants.AF_PACKET;
		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.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;

		@@ -52,6 +58,7 @@ import android.net.shared.ProvisioningConfiguration;
		import android.net.shared.ProvisioningConfiguration.ScanResultInfo;
		import android.net.shared.ProvisioningConfiguration.ScanResultInfo.InformationElement;
		import android.net.util.InterfaceParams;
		import android.net.util.NetworkStackUtils;
		import android.net.util.SharedLog;
		import android.os.Build;
		import android.os.ConditionVariable;
		@@ -61,6 +68,8 @@ import android.os.RemoteException;
		import android.os.ServiceSpecificException;
		import android.os.SystemClock;
		import android.stats.connectivity.DisconnectCode;
		import android.system.ErrnoException;
		import android.system.Os;
		import android.text.TextUtils;
		import android.util.LocalLog;
		import android.util.Log;
		@@ -79,16 +88,21 @@ import com.android.internal.util.StateMachine;
		import com.android.internal.util.WakeupMessage;
		import com.android.net.module.util.DeviceConfigUtils;
		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.metrics.IpProvisioningMetrics;
		import com.android.networkstack.packets.NeighborAdvertisement;
		import com.android.server.NetworkObserverRegistry;
		import com.android.server.NetworkStackService.NetworkStackServiceManager;

		import java.io.FileDescriptor;
		import java.io.PrintWriter;
		import java.net.Inet6Address;
		import java.net.InetAddress;
		import java.net.MalformedURLException;
		import java.net.SocketAddress;
		import java.net.SocketException;
		import java.net.URL;
		import java.nio.BufferUnderflowException;
		import java.nio.ByteBuffer;
		@@ -479,6 +493,8 @@ public class IpClient extends StateMachine {
		private final MessageHandlingLogger mMsgStateLogger;
		private final IpConnectivityLog mMetricsLog;
		private final InterfaceController mInterfaceCtrl;
		// Set of IPv6 addresses for which unsolicited gratuitous NA packets have been sent.
		private final Set<Inet6Address> mGratuitousNaTargetAddresses = new HashSet<>();

		// Ignore nonzero RDNSS option lifetimes below this value. 0 = disabled.
		private final int mMinRdnssLifetimeSec;
		@@ -564,6 +580,16 @@ public class IpClient extends StateMachine {
		public IpConnectivityLog getIpConnectivityLog() {
		return new IpConnectivityLog();
		}

		/**
		* Return whether a feature guarded by a feature flag is enabled.
		* @see NetworkStackUtils#isFeatureEnabled(Context, String, String)
		*/
		public boolean isFeatureEnabled(final Context context, final String name,
		boolean defaultEnabled) {
		return DeviceConfigUtils.isFeatureEnabled(context, NAMESPACE_CONNECTIVITY, name,
		defaultEnabled);
		}
		}

		public IpClient(Context context, String ifName, IIpClientCallbacks callback,
		@@ -647,6 +673,21 @@ public class IpClient extends StateMachine {
		logMsg(msg);
		}

		@Override
		public void onInterfaceAddressRemoved(LinkAddress address, String iface) {
		super.onInterfaceAddressRemoved(address, iface);
		if (!mInterfaceName.equals(iface)) return;
		if (!address.isIpv6()) return;
		final Inet6Address targetIp = (Inet6Address) address.getAddress();
		if (mGratuitousNaTargetAddresses.contains(targetIp)) {
		mGratuitousNaTargetAddresses.remove(targetIp);

		final String msg = "Global IPv6 address: " + targetIp
		+ " has removed from the set of gratuitous NA target address.";
		logMsg(msg);
		}
		}

		private void logMsg(String msg) {
		Log.d(mTag, msg);
		getHandler().post(() -> mLog.log("OBSERVED " + msg));
		@@ -793,6 +834,11 @@ public class IpClient extends StateMachine {
		mLinkObserver.shutdown();
		}

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

		@Override
		protected void onQuitting() {
		mCallback.onQuit();
		@@ -1377,6 +1423,57 @@ 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);
		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);
		} finally {
		NetworkStackUtils.closeSocketQuietly(sock);
		}
		}

		private Inet6Address getIpv6LinkLocalAddress(final LinkProperties newLp) {
		Inet6Address src = null;
		for (LinkAddress la : newLp.getLinkAddresses()) {
		if (!la.isIpv6()) continue;
		final Inet6Address ip = (Inet6Address) la.getAddress();
		if (ip.isLinkLocalAddress()) return ip;
		}
		return null;
		}

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

		final Inet6Address src = getIpv6LinkLocalAddress(newLp);
		if (src == null) return;
		for (LinkAddress la : newLp.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;
		if (DBG) {
		Log.d(mTag, "send Gratuitous NA from " + src + ", target Address is "
		+ targetIp);
		}
		sendGratuitousNA(src, targetIp);
		mGratuitousNaTargetAddresses.add(targetIp);
		}
		}

		// Returns false if we have lost provisioning, true otherwise.
		private boolean handleLinkPropertiesUpdate(boolean sendCallbacks) {
		final LinkProperties newLp = assembleLinkProperties();
		@@ -1384,6 +1481,11 @@ public class IpClient extends StateMachine {
		return true;
		}

		// 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);

		// Either success IPv4 or IPv6 provisioning triggers new LinkProperties update,
		// wait for the provisioning completion and record the latency.
		mIpProvisioningMetrics.setIPv4ProvisionedLatencyOnFirstTime(newLp.isIpv4Provisioned());
		@@ -1662,6 +1764,7 @@ public class IpClient extends StateMachine {
		public void enter() {
		stopAllIP();
		mHasDisabledIPv6OnProvLoss = false;
		mGratuitousNaTargetAddresses.clear();

		mLinkObserver.clearInterfaceParams();
		resetLinkProperties();

src/android/net/util/NetworkStackUtils.java

+25 −0

Original line number	Diff line number	Diff line
		@@ -17,12 +17,16 @@
		package android.net.util;

		import android.content.Context;
		import android.net.MacAddress;

		import androidx.annotation.NonNull;

		import com.android.net.module.util.DeviceConfigUtils;

		import java.io.FileDescriptor;
		import java.io.IOException;
		import java.net.Inet4Address;
		import java.net.Inet6Address;
		import java.net.SocketException;

		/**
		@@ -232,6 +236,12 @@ public class NetworkStackUtils {
		*/
		public static final String VALIDATION_METRICS_VERSION = "validation_metrics_version";

		/**
		* Experiment flag to enable sending gratuitous multicast unsolicited Neighbor Advertisements
		* to propagate new assigned IPv6 GUA as quickly as possible.
		*/
		public static final String IPCLIENT_GRATUITOUS_NA_VERSION = "ipclient_gratuitous_na_version";

		static {
		System.loadLibrary("networkstackutilsjni");
		}
		@@ -246,6 +256,21 @@ public class NetworkStackUtils {
		}
		}

		/**
		* Convert IPv6 multicast address to ethernet multicast address in network order.
		*/
		public static MacAddress ipv6MulticastToEthernetMulticast(@NonNull final Inet6Address addr) {
		final byte[] etherMulticast = new byte[6];
		final byte[] ipv6Multicast = addr.getAddress();
		etherMulticast[0] = (byte) 0x33;
		etherMulticast[1] = (byte) 0x33;
		etherMulticast[2] = ipv6Multicast[12];
		etherMulticast[3] = ipv6Multicast[13];
		etherMulticast[4] = ipv6Multicast[14];
		etherMulticast[5] = ipv6Multicast[15];
		return MacAddress.fromBytes(etherMulticast);
		}

		/**
		* Attaches a socket filter that accepts DHCP packets to the given socket.
		*/

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

+79 −1

Original line number	Diff line number	Diff line
		@@ -39,11 +39,15 @@ 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_HEADER_LEN;
		import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_OFFSET;
		import static com.android.net.module.util.NetworkStackConstants.ICMPV6_NEIGHBOR_ADVERTISEMENT;
		import static com.android.net.module.util.NetworkStackConstants.ICMPV6_ROUTER_SOLICITATION;
		import static com.android.net.module.util.NetworkStackConstants.IPV4_ADDR_ANY;
		import static com.android.net.module.util.NetworkStackConstants.IPV6_ADDR_ALL_NODES_MULTICAST;
		import static com.android.net.module.util.NetworkStackConstants.IPV6_ADDR_ALL_ROUTERS_MULTICAST;
		import static com.android.net.module.util.NetworkStackConstants.IPV6_HEADER_LEN;
		import static com.android.net.module.util.NetworkStackConstants.IPV6_PROTOCOL_OFFSET;
		import static com.android.net.module.util.NetworkStackConstants.PIO_FLAG_AUTONOMOUS;
		import static com.android.net.module.util.NetworkStackConstants.PIO_FLAG_ON_LINK;

		import static junit.framework.Assert.fail;

		@@ -141,6 +145,7 @@ import com.android.networkstack.apishim.ConstantsShim;
		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.NetworkObserver;
		import com.android.server.NetworkObserverRegistry;
		import com.android.server.NetworkStackService.NetworkStackServiceManager;
		@@ -390,6 +395,7 @@ public abstract class IpClientIntegrationTestCommon {
		return mDhcpClient;
		}

		@Override
		public boolean isFeatureEnabled(final Context context, final String name,
		final boolean defaultEnabled) {
		return IpClientIntegrationTestCommon.this.isFeatureEnabled(name, defaultEnabled);
		@@ -688,6 +694,14 @@ public abstract class IpClientIntegrationTestCommon {
		}
		}

		private NeighborAdvertisement parseNeighborAdvertisementOrNull(final byte[] packet) {
		try {
		return NeighborAdvertisement.parse(packet, packet.length);
		} catch (NeighborAdvertisement.ParseException e) {
		return null;
		}
		}

		private static ByteBuffer buildDhcpOfferPacket(final DhcpPacket packet,
		final Inet4Address clientAddress, final Integer leaseTimeSec, final short mtu,
		final String captivePortalUrl, final Integer ipv6OnlyWaitTime) {
		@@ -1418,6 +1432,24 @@ public abstract class IpClientIntegrationTestCommon {
		== (byte) ICMPV6_ROUTER_SOLICITATION;
		}

		private boolean isNeighborAdvertisement(final byte[] packetBytes) {
		ByteBuffer packet = ByteBuffer.wrap(packetBytes);
		return packet.getShort(ETHER_TYPE_OFFSET) == (short) ETH_P_IPV6
		&& packet.get(ETHER_HEADER_LEN + IPV6_PROTOCOL_OFFSET) == (byte) IPPROTO_ICMPV6
		&& packet.get(ETHER_HEADER_LEN + IPV6_HEADER_LEN)
		== (byte) ICMPV6_NEIGHBOR_ADVERTISEMENT;
		}

		private NeighborAdvertisement getNextNeighborAdvertisement() throws ParseException {
		final byte[] packet = mPacketReader.popPacket(PACKET_TIMEOUT_MS,
		this::isNeighborAdvertisement);
		if (packet == null) return null;

		final NeighborAdvertisement na = parseNeighborAdvertisementOrNull(packet);
		assertNotNull("Invalid neighbour advertisement received", na);
		return na;
		}

		private void waitForRouterSolicitation() throws ParseException {
		assertNotNull("No router solicitation received on interface within timeout",
		mPacketReader.popPacket(PACKET_TIMEOUT_MS, this::isRouterSolicitation));
		@@ -1448,7 +1480,7 @@ public abstract class IpClientIntegrationTestCommon {
		private static ByteBuffer buildPioOption(int valid, int preferred, String prefixString)
		throws Exception {
		return PrefixInformationOption.build(new IpPrefix(prefixString),
		(byte) 0b11000000 /* L = 1, A = 1 */, valid, preferred);
		(byte) (PIO_FLAG_ON_LINK \| PIO_FLAG_AUTONOMOUS), valid, preferred);
		}

		private static ByteBuffer buildRdnssOption(int lifetime, String... servers) throws Exception {
		@@ -2744,4 +2776,50 @@ public abstract class IpClientIntegrationTestCommon {
		assertArrayEquals(packet.mUserClass, TEST_OEM_USER_CLASS_INFO);
		assertFalse(packet.hasRequestedParam((byte) 42 /* NTP_SERVER */));
		}

		private void assertGratuitousNa(final NeighborAdvertisement na) throws Exception {
		final MacAddress etherMulticast =
		NetworkStackUtils.ipv6MulticastToEthernetMulticast(IPV6_ADDR_ALL_ROUTERS_MULTICAST);
		final LinkAddress target = new LinkAddress(na.naHdr.target, 64);

		assertEquals(etherMulticast, na.ethHdr.dstMac);
		assertEquals(ETH_P_IPV6, na.ethHdr.etherType);
		assertEquals(IPPROTO_ICMPV6, na.ipv6Hdr.nextHeader);
		assertEquals(0xff, na.ipv6Hdr.hopLimit);
		assertTrue(na.ipv6Hdr.srcIp.isLinkLocalAddress());
		assertEquals(IPV6_ADDR_ALL_ROUTERS_MULTICAST, na.ipv6Hdr.dstIp);
		assertEquals(ICMPV6_NEIGHBOR_ADVERTISEMENT, na.icmpv6Hdr.type);
		assertEquals(0, na.icmpv6Hdr.code);
		assertEquals(0, na.naHdr.flags);
		assertTrue(target.isGlobalPreferred());
		}

		@Test
		public void testGratuitousNa() throws Exception {
		final ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.withoutIPv4()
		.build();

		setFeatureEnabled(NetworkStackUtils.IPCLIENT_GRATUITOUS_NA_VERSION,
		true /* isGratuitousNaEnabled */);
		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);

		final List<NeighborAdvertisement> naList = new ArrayList<>();
		NeighborAdvertisement packet;
		while ((packet = getNextNeighborAdvertisement()) != null) {
		assertGratuitousNa(packet);
		naList.add(packet);
		}
		assertEquals(2, naList.size()); // privacy address and stable privacy address
		}
		}