Merge "Always give VPN the INTERNET capability." (6d5a4a3b) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/connectivity/Vpn.java

+9 −18

Original line number	Diff line number	Diff line
		@@ -953,30 +953,21 @@ public class Vpn {
		return false;
		}

		LinkProperties lp = makeLinkProperties();
		final boolean hadInternetCapability = mNetworkCapabilities.hasCapability(
		NetworkCapabilities.NET_CAPABILITY_INTERNET);
		final boolean willHaveInternetCapability = providesRoutesToMostDestinations(lp);
		if (hadInternetCapability != willHaveInternetCapability) {
		// A seamless handover would have led to a change to INTERNET capability, which
		// is supposed to be immutable for a given network. In this case bail out and do not
		// perform handover.
		Log.i(TAG, "Handover not possible due to changes to INTERNET capability");
		return false;
		}

		agent.sendLinkProperties(lp);
		agent.sendLinkProperties(makeLinkProperties());
		return true;
		}

		private void agentConnect() {
		LinkProperties lp = makeLinkProperties();

		if (providesRoutesToMostDestinations(lp)) {
		// VPN either provide a default route (IPv4 or IPv6 or both), or they are a split tunnel
		// that falls back to the default network, which by definition provides INTERNET (unless
		// there is no default network, in which case none of this matters in any sense).
		// Also, it guarantees that when a VPN applies to an app, the VPN will always be reported
		// as the network by getDefaultNetwork and registerDefaultNetworkCallback. This in turn
		// protects the invariant that apps calling CM#bindProcessToNetwork(getDefaultNetwork())
		// the same as if they use the default network.
		mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
		} else {
		mNetworkCapabilities.removeCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
		}

		mNetworkInfo.setDetailedState(DetailedState.CONNECTING, null, null);

tests/net/java/com/android/server/connectivity/VpnTest.java

+0 −90

Original line number	Diff line number	Diff line
		@@ -727,94 +727,4 @@ public class VpnTest {
		"::/1", "8000::/2", "c000::/3", "e000::/4", "f000::/5", "f800::/6",
		"fe00::/8", "2605:ef80:e:af1d::/64");
		}

		@Test
		public void testProvidesRoutesToMostDestinations() {
		final LinkProperties lp = new LinkProperties();

		// Default route provides routes to all IPv4 destinations.
		lp.addRoute(new RouteInfo(new IpPrefix("0.0.0.0/0")));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		// Empty LP provides routes to no destination
		lp.clear();
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));

		// All IPv4 routes except for local networks. This is the case most relevant
		// to this function. It provides routes to almost the entire space.
		// (clone the stream so that we can reuse it later)
		publicIpV4Routes().forEach(s -> lp.addRoute(new RouteInfo(new IpPrefix(s))));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		// Removing a 16-bit prefix, which is 65536 addresses. This is still enough to
		// provide routes to "most" destinations.
		lp.removeRoute(new RouteInfo(new IpPrefix("192.169.0.0/16")));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		// Remove the /2 route, which represent a quarter of the available routing space.
		// This LP does not provides routes to "most" destinations any more.
		lp.removeRoute(new RouteInfo(new IpPrefix("64.0.0.0/2")));
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));

		lp.clear();
		publicIpV6Routes().forEach(s -> lp.addRoute(new RouteInfo(new IpPrefix(s))));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		lp.removeRoute(new RouteInfo(new IpPrefix("::/1")));
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));

		// V6 does not provide sufficient coverage but v4 does
		publicIpV4Routes().forEach(s -> lp.addRoute(new RouteInfo(new IpPrefix(s))));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		// V4 still does
		lp.removeRoute(new RouteInfo(new IpPrefix("192.169.0.0/16")));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		// V4 does not any more
		lp.removeRoute(new RouteInfo(new IpPrefix("64.0.0.0/2")));
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));

		// V4 does not, but V6 has sufficient coverage again
		lp.addRoute(new RouteInfo(new IpPrefix("::/1")));
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));

		lp.clear();
		// V4-unreachable route should not be treated as sufficient coverage
		lp.addRoute(new RouteInfo(new IpPrefix(Inet4Address.ANY, 0), RTN_UNREACHABLE));
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));

		lp.clear();
		// V6-unreachable route should not be treated as sufficient coverage
		lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), RTN_UNREACHABLE));
		assertFalse(Vpn.providesRoutesToMostDestinations(lp));
		}

		@Test
		public void testDoesNotLockUpWithTooManyRoutes() {
		final LinkProperties lp = new LinkProperties();
		final byte[] ad = new byte[4];
		// Actually evaluating this many routes under 1500ms is impossible on
		// current hardware and for some time, as the algorithm is O(n²).
		// Make sure the system has a safeguard against this and does not
		// lock up.
		final int MAX_ROUTES = 4000;
		final long MAX_ALLOWED_TIME_MS = 1500;
		for (int i = 0; i < MAX_ROUTES; ++i) {
		ad[0] = (byte)((i >> 24) & 0xFF);
		ad[1] = (byte)((i >> 16) & 0xFF);
		ad[2] = (byte)((i >> 8) & 0xFF);
		ad[3] = (byte)(i & 0xFF);
		try {
		lp.addRoute(new RouteInfo(new IpPrefix(Inet4Address.getByAddress(ad), 32)));
		} catch (UnknownHostException e) {
		// UnknownHostException is only thrown for an address of illegal length,
		// which can't happen in the case above.
		}
		}
		final long start = SystemClock.currentThreadTimeMillis();
		assertTrue(Vpn.providesRoutesToMostDestinations(lp));
		final long end = SystemClock.currentThreadTimeMillis();
		assertTrue(end - start < MAX_ALLOWED_TIME_MS);
		}
		}