Merge "Carefully select which DNS servers to send to netd" into mnc-dev (3d54e672) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/ConnectivityService.java

+45 −1

Original line number	Diff line number	Diff line
		@@ -136,11 +136,13 @@ import java.io.FileReader;
		import java.io.IOException;
		import java.io.PrintWriter;
		import java.net.Inet4Address;
		import java.net.Inet6Address;
		import java.net.InetAddress;
		import java.net.UnknownHostException;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.Collection;
		import java.util.Collections;
		import java.util.HashMap;
		import java.util.HashSet;
		import java.util.Iterator;
		@@ -3920,10 +3922,52 @@ public class ConnectivityService extends IConnectivityManager.Stub
		}
		return !routeDiff.added.isEmpty() \|\| !routeDiff.removed.isEmpty();
		}

		// TODO: investigate moving this into LinkProperties, if only to make more accurate
		// the isProvisioned() checks.
		private static Collection<InetAddress> getLikelyReachableDnsServers(LinkProperties lp) {
		final ArrayList<InetAddress> dnsServers = new ArrayList<InetAddress>();
		final List<RouteInfo> allRoutes = lp.getAllRoutes();
		for (InetAddress nameserver : lp.getDnsServers()) {
		// If the LinkProperties doesn't include a route to the nameserver, ignore it.
		final RouteInfo bestRoute = RouteInfo.selectBestRoute(allRoutes, nameserver);
		if (bestRoute == null) {
		continue;
		}

		// TODO: better source address evaluation for destination addresses.
		if (nameserver instanceof Inet4Address) {
		if (!lp.hasIPv4Address()) {
		continue;
		}
		} else if (nameserver instanceof Inet6Address) {
		if (nameserver.isLinkLocalAddress()) {
		if (((Inet6Address)nameserver).getScopeId() == 0) {
		// For now, just make sure link-local DNS servers have
		// scopedIds set, since DNS lookups will fail otherwise.
		// TODO: verify the scopeId matches that of lp's interface.
		continue;
		}
		} else {
		if (bestRoute.isIPv6Default() && !lp.hasGlobalIPv6Address()) {
		// TODO: reconsider all corner cases (disconnected ULA networks, ...).
		continue;
		}
		}
		}

		dnsServers.add(nameserver);
		}
		return Collections.unmodifiableList(dnsServers);
		}

		private void updateDnses(LinkProperties newLp, LinkProperties oldLp, int netId,
		boolean flush, boolean useDefaultDns) {
		// TODO: consider comparing the getLikelyReachableDnsServers() lists, in case the
		// route to a DNS server has been removed (only really applicable in special cases
		// where there is no default route).
		if (oldLp == null \|\| (newLp.isIdenticalDnses(oldLp) == false)) {
		Collection<InetAddress> dnses = newLp.getDnsServers();
		Collection<InetAddress> dnses = getLikelyReachableDnsServers(newLp);
		if (dnses.size() == 0 && mDefaultDns != null && useDefaultDns) {
		dnses = new ArrayList();
		dnses.add(mDefaultDns);