Listen for pref64 RA attributes in IpClientLinkObserver. am: 70d7ffa59f (6a4c7391) · Commits · e / os / android_packages_modules_NetworkStack

common/netlinkclient/src/android/net/netlink/NetlinkConstants.java

+4 −0

Original line number	Diff line number	Diff line
		@@ -106,6 +106,10 @@ public class NetlinkConstants {
		/* see <linux_src>/include/uapi/linux/sock_diag.h */
		public static final short SOCK_DIAG_BY_FAMILY = 20;

		// Netlink groups.
		public static final int RTNLGRP_ND_USEROPT = 20;
		public static final int RTMGRP_ND_USEROPT = 1 << (RTNLGRP_ND_USEROPT - 1);

		public static String stringForNlMsgType(short nlm_type) {
		switch (nlm_type) {
		case NLMSG_NOOP: return "NLMSG_NOOP";

src/android/net/ip/IpClient.java

+5 −1

Original line number	Diff line number	Diff line
		@@ -583,7 +583,8 @@ public class IpClient extends StateMachine {

		mLinkObserver = new IpClientLinkObserver(
		mInterfaceName,
		() -> sendMessage(EVENT_NETLINK_LINKPROPERTIES_CHANGED), config) {
		() -> sendMessage(EVENT_NETLINK_LINKPROPERTIES_CHANGED),
		config, getHandler(), mLog) {
		@Override
		public void onInterfaceAdded(String iface) {
		super.onInterfaceAdded(iface);
		@@ -1230,6 +1231,7 @@ public class IpClient extends StateMachine {
		newLp.addRoute(route);
		}
		addAllReachableDnsServers(newLp, netlinkLinkProperties.getDnsServers());
		newLp.setNat64Prefix(netlinkLinkProperties.getNat64Prefix());

		// [3] Add in data from DHCPv4, if available.
		//
		@@ -1568,6 +1570,7 @@ public class IpClient extends StateMachine {
		public void enter() {
		stopAllIP();

		mLinkObserver.clearInterfaceParams();
		resetLinkProperties();
		if (mStartTimeMillis > 0) {
		// Completed a life-cycle; send a final empty LinkProperties
		@@ -1713,6 +1716,7 @@ public class IpClient extends StateMachine {
		transitionTo(mStoppedState);
		return;
		}
		mLinkObserver.setInterfaceParams(mInterfaceParams);
		mCallback.setNeighborDiscoveryOffload(true);
		}

src/android/net/ip/IpClientLinkObserver.java

+127 −2

Original line number	Diff line number	Diff line
		@@ -16,12 +16,27 @@

		package android.net.ip;

		import static android.system.OsConstants.AF_INET6;

		import static com.android.server.util.NetworkStackConstants.ICMPV6_ROUTER_ADVERTISEMENT;

		import android.net.InetAddresses;
		import android.net.IpPrefix;
		import android.net.LinkAddress;
		import android.net.LinkProperties;
		import android.net.RouteInfo;
		import android.net.netlink.NduseroptMessage;
		import android.net.netlink.NetlinkConstants;
		import android.net.netlink.NetlinkMessage;
		import android.net.netlink.StructNdOptPref64;
		import android.net.util.InterfaceParams;
		import android.net.util.SharedLog;
		import android.os.Handler;
		import android.system.OsConstants;
		import android.util.Log;

		import com.android.networkstack.apishim.NetworkInformationShim;
		import com.android.networkstack.apishim.NetworkInformationShimImpl;
		import com.android.server.NetworkObserver;

		import java.net.InetAddress;
		@@ -31,6 +46,7 @@ import java.util.Collections;
		import java.util.HashMap;
		import java.util.HashSet;
		import java.util.Set;
		import java.util.concurrent.TimeUnit;

		/**
		* Keeps track of link configuration received from Netd.
		@@ -56,6 +72,10 @@ import java.util.Set;
		* - All accesses to mLinkProperties must be synchronized(this). All the other
		* member variables are immutable once the object is constructed.
		*
		* TODO: Now that all the methods are called on the handler thread, remove synchronization and
		* pass the LinkProperties to the update() callback.
		* TODO: Stop extending NetworkObserver and get events from netlink directly.
		*
		* @hide
		*/
		public class IpClientLinkObserver implements NetworkObserver {
		@@ -86,16 +106,21 @@ public class IpClientLinkObserver implements NetworkObserver {
		private DnsServerRepository mDnsServerRepository;
		private final Configuration mConfig;

		private final MyNetlinkMonitor mNetlinkMonitor;

		private static final boolean DBG = false;

		public IpClientLinkObserver(String iface, Callback callback, Configuration config) {
		mTag = "NetlinkTracker/" + iface;
		public IpClientLinkObserver(String iface, Callback callback, Configuration config,
		Handler h, SharedLog log) {
		mInterfaceName = iface;
		mTag = "NetlinkTracker/" + mInterfaceName;
		mCallback = callback;
		mLinkProperties = new LinkProperties();
		mLinkProperties.setInterfaceName(mInterfaceName);
		mConfig = config;
		mDnsServerRepository = new DnsServerRepository(config.minRdnssLifetime);
		mNetlinkMonitor = new MyNetlinkMonitor(h, log, mTag);
		h.post(mNetlinkMonitor::start);
		}

		private void maybeLog(String operation, String iface, LinkAddress address) {
		@@ -213,6 +238,106 @@ public class IpClientLinkObserver implements NetworkObserver {
		mLinkProperties.setInterfaceName(mInterfaceName);
		}

		/** Notifies this object of new interface parameters. */
		public void setInterfaceParams(InterfaceParams params) {
		mNetlinkMonitor.setIfindex(params.index);
		}

		/** Notifies this object not to listen on any interface. */
		public void clearInterfaceParams() {
		mNetlinkMonitor.setIfindex(0); // 0 is never a valid ifindex.
		}

		/**
		* Simple NetlinkMonitor. Currently only listens for PREF64 events.
		* All methods except the constructor must be called on the handler thread.
		*/
		private class MyNetlinkMonitor extends NetlinkMonitor {
		MyNetlinkMonitor(Handler h, SharedLog log, String tag) {
		super(h, log, tag, OsConstants.NETLINK_ROUTE, NetlinkConstants.RTMGRP_ND_USEROPT);
		}

		private final NetworkInformationShim mShim = NetworkInformationShimImpl.newInstance();

		private long mNat64PrefixExpiry;

		/**
		* Current interface index. Most of this class (and of IpClient), only uses interface names,
		* not interface indices. This means that the interface index can in theory change, and that
		* it's not necessarily correct to get the interface name at object creation time (and in
		* fact, when the object is created, the interface might not even exist).
		* TODO: once all netlink events pass through this class, stop depending on interface names.
		*/
		private int mIfindex;

		void setIfindex(int ifindex) {
		mIfindex = ifindex;
		}

		/**
		* Processes a PREF64 ND option.
		*
		* @param prefix The NAT64 prefix.
		* @param now The time (as determined by SystemClock.elapsedRealtime) when the event
		* that triggered this method was received.
		* @param expiry The time (as determined by SystemClock.elapsedRealtime) when the option
		* expires.
		*/
		private synchronized void updatePref64(IpPrefix prefix, final long now,
		final long expiry) {
		final IpPrefix currentPrefix = mShim.getNat64Prefix(mLinkProperties);

		// If the prefix matches the current prefix, refresh its lifetime.
		if (prefix.equals(currentPrefix)) {
		mNat64PrefixExpiry = expiry;
		}

		// If we already have a prefix, continue using it and ignore the new one. Stopping and
		// restarting clatd is disruptive because it will break existing IPv4 connections.
		if (mNat64PrefixExpiry > now) return;

		// The current prefix has expired. Either replace it with the new one or delete it.
		if (expiry > now) {
		// If expiry > now, then prefix != currentPrefix (due to the return statement above)
		mShim.setNat64Prefix(mLinkProperties, prefix);
		mNat64PrefixExpiry = expiry;
		} else {
		mShim.setNat64Prefix(mLinkProperties, null);
		mNat64PrefixExpiry = 0;
		}

		mCallback.update();

		// TODO: send a delayed message to remove the prefix when it expires.
		}

		private void processPref64Option(StructNdOptPref64 opt, final long now) {
		final long expiry = now + TimeUnit.SECONDS.toMillis(opt.lifetime);
		updatePref64(opt.prefix, now, expiry);
		}

		private void processNduseroptMessage(NduseroptMessage msg, final long whenMs) {
		if (msg.family != AF_INET6 \|\| msg.option == null \|\| msg.ifindex != mIfindex) return;
		if (msg.icmp_type != (byte) ICMPV6_ROUTER_ADVERTISEMENT) return;

		switch (msg.option.type) {
		case StructNdOptPref64.TYPE:
		processPref64Option((StructNdOptPref64) msg.option, whenMs);
		break;

		default:
		// TODO: implement RDNSS and DNSSL.
		break;
		}
		}

		@Override
		protected void processNetlinkMessage(NetlinkMessage nlMsg, long whenMs) {
		if (!(nlMsg instanceof NduseroptMessage)) return;
		processNduseroptMessage((NduseroptMessage) nlMsg, whenMs);
		}
		}

		/**
		* Tracks DNS server updates received from Netlink.
		*

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

+86 −2

Original line number	Diff line number	Diff line
		@@ -65,6 +65,7 @@ import static org.mockito.Mockito.argThat;
		import static org.mockito.Mockito.doAnswer;
		import static org.mockito.Mockito.doThrow;
		import static org.mockito.Mockito.eq;
		import static org.mockito.Mockito.inOrder;
		import static org.mockito.Mockito.never;
		import static org.mockito.Mockito.reset;
		import static org.mockito.Mockito.spy;
		@@ -103,6 +104,7 @@ import android.net.dhcp.DhcpRequestPacket;
		import android.net.ipmemorystore.NetworkAttributes;
		import android.net.ipmemorystore.OnNetworkAttributesRetrievedListener;
		import android.net.ipmemorystore.Status;
		import android.net.netlink.StructNdOptPref64;
		import android.net.shared.Layer2Information;
		import android.net.shared.ProvisioningConfiguration;
		import android.net.shared.ProvisioningConfiguration.ScanResultInfo;
		@@ -141,6 +143,7 @@ import org.junit.Rule;
		import org.junit.Test;
		import org.junit.runner.RunWith;
		import org.mockito.ArgumentCaptor;
		import org.mockito.InOrder;
		import org.mockito.Mock;
		import org.mockito.MockitoAnnotations;
		import org.mockito.Spy;
		@@ -1278,12 +1281,16 @@ public class IpClientIntegrationTest {
		return packet;
		}

		@Test
		public void testRaRdnss() throws Exception {
		private void disableRouterSolicitationDelay() throws Exception {
		// Speed up the test by removing router_solicitation_delay.
		// We don't need to restore the default value because the interface is removed in tearDown.
		// TODO: speed up further by not waiting for RA but keying off first IPv6 packet.
		mNetd.setProcSysNet(INetd.IPV6, INetd.CONF, mIfaceName, "router_solicitation_delay", "0");
		}

		@Test
		public void testRaRdnss() throws Exception {
		disableRouterSolicitationDelay();

		ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		@@ -1337,6 +1344,83 @@ public class IpClientIntegrationTest {
		reset(mCb);
		}

		private void expectNat64PrefixUpdate(InOrder inOrder, IpPrefix expected) throws Exception {
		inOrder.verify(mCb, timeout(TEST_TIMEOUT_MS)).onLinkPropertiesChange(
		argThat(lp -> Objects.equals(expected, lp.getNat64Prefix())));

		}

		private void expectNoNat64PrefixUpdate(InOrder inOrder, IpPrefix unchanged) throws Exception {
		HandlerUtilsKt.waitForIdle(mIpc.getHandler(), TEST_TIMEOUT_MS);
		inOrder.verify(mCb, never()).onLinkPropertiesChange(argThat(
		lp -> !Objects.equals(unchanged, lp.getNat64Prefix())));

		}

		@Test @IgnoreUpTo(Build.VERSION_CODES.Q)
		public void testPref64Option() throws Exception {
		disableRouterSolicitationDelay();

		ProvisioningConfiguration config = new ProvisioningConfiguration.Builder()
		.withoutIpReachabilityMonitor()
		.withoutIPv4()
		.build();
		mIpc.startProvisioning(config);

		final String dnsServer = "2001:4860:4860::64";
		final IpPrefix prefix = new IpPrefix("64:ff9b::/96");
		final IpPrefix otherPrefix = new IpPrefix("2001:db8:64::/96");

		final ByteBuffer pio = buildPioOption(600, 300, "2001:db8:1::/64");
		ByteBuffer rdnss = buildRdnssOption(600, dnsServer);
		ByteBuffer pref64 = new StructNdOptPref64(prefix, 600).toByteBuffer();
		ByteBuffer ra = buildRaPacket(pio, rdnss, pref64);

		waitForRouterSolicitation();
		mPacketReader.sendResponse(ra);

		InOrder inOrder = inOrder(mCb);
		ArgumentCaptor<LinkProperties> captor = ArgumentCaptor.forClass(LinkProperties.class);
		inOrder.verify(mCb, timeout(TEST_TIMEOUT_MS)).onProvisioningSuccess(captor.capture());

		// The NAT64 prefix might have been detected before or after provisioning success.
		LinkProperties lp = captor.getValue();
		if (lp.getNat64Prefix() != null) {
		assertEquals(prefix, lp.getNat64Prefix());
		} else {
		expectNat64PrefixUpdate(inOrder, prefix);
		}

		// Increase the lifetime and expect the prefix not to change.
		pref64 = new StructNdOptPref64(prefix, 1800).toByteBuffer();
		ra = buildRaPacket(pio, rdnss, pref64);
		mPacketReader.sendResponse(ra);
		expectNoNat64PrefixUpdate(inOrder, prefix);

		// Withdraw the prefix and expect it to be set to null.
		pref64 = new StructNdOptPref64(prefix, 0).toByteBuffer();
		ra = buildRaPacket(pio, rdnss, pref64);
		mPacketReader.sendResponse(ra);
		expectNat64PrefixUpdate(inOrder, null);

		// Re-announce the prefix.
		pref64 = new StructNdOptPref64(prefix, 600).toByteBuffer();
		ra = buildRaPacket(pio, rdnss, pref64);
		mPacketReader.sendResponse(ra);
		expectNat64PrefixUpdate(inOrder, prefix);

		// Announce two prefixes. Don't expect any update because if there is already a NAT64
		// prefix, any new prefix is ignored.
		ByteBuffer otherPref64 = new StructNdOptPref64(otherPrefix, 600).toByteBuffer();
		ra = buildRaPacket(pio, rdnss, pref64, otherPref64);
		mPacketReader.sendResponse(ra);

		pref64 = new StructNdOptPref64(prefix, 0).toByteBuffer();
		ra = buildRaPacket(pio, rdnss, pref64, otherPref64);
		mPacketReader.sendResponse(ra);
		expectNat64PrefixUpdate(inOrder, otherPrefix);
		}

		@Test
		public void testIpClientClearingIpAddressState() throws Exception {
		final long currentTime = System.currentTimeMillis();