From 7c9b1c757a407760de93e442c71d5dd988a70a8c Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Sat, 26 Oct 2019 01:20:57 +0900 Subject: [PATCH 1/2] Add test coverage for strict mode private DNS. Support faking out the DNS lookups used by NetworkMonitor to resolve strict mode DNS, and add more test coverage. These tests were partly adapted from tests we have in Q but also contain new coverage. This is because in Q the interface between ConnectivityService and NetworkMonitor changed substantially, and it is impractical to backport NetworkMonitorTest. Bug: 122652057 Test: atest FrameworksNetTests Change-Id: I6497b7efa539267576d38d3036eef0af0df4e9cb Merged-In: Iaa78a7edcf23755c89d7b354edbc28d37d74d891 --- .../server/ConnectivityServiceTest.java | 117 +++++++++++++++++- 1 file changed, 111 insertions(+), 6 deletions(-) diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java index e6a889b1c2..d7a64dd38d 100644 --- a/tests/net/java/com/android/server/ConnectivityServiceTest.java +++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java @@ -165,6 +165,7 @@ import org.mockito.MockitoAnnotations; import org.mockito.Spy; import java.net.InetAddress; +import java.net.UnknownHostException; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; @@ -455,6 +456,10 @@ public class ConnectivityServiceTest { mNetworkAgent.sendNetworkScore(mScore); } + public int getScore() { + return mScore; + } + public void explicitlySelected(boolean acceptUnvalidated) { mNetworkAgent.explicitlySelected(acceptUnvalidated); } @@ -869,6 +874,7 @@ public class ConnectivityServiceTest { // HTTP response code fed back to NetworkMonitor for Internet connectivity probe. public int gen204ProbeResult = 500; public String gen204ProbeRedirectUrl = null; + public volatile InetAddress[] dnsLookupResults = null; public WrappedNetworkMonitor(Context context, Handler handler, NetworkAgentInfo networkAgentInfo, NetworkRequest defaultRequest, @@ -883,6 +889,25 @@ public class ConnectivityServiceTest { if (!mIsCaptivePortalCheckEnabled) { return new CaptivePortalProbeResult(204); } return new CaptivePortalProbeResult(gen204ProbeResult, gen204ProbeRedirectUrl, null); } + + private InetAddress[] fakeDnsLookup() throws UnknownHostException { + if (dnsLookupResults == null) { + throw new UnknownHostException(); + } + return dnsLookupResults; + } + + @Override + protected InetAddress[] getAllByName(Network network, String hostname) + throws UnknownHostException { + return fakeDnsLookup(); + } + + @Override + protected InetAddress[] resolveAllLocally(Network network, String hostname, int flags) + throws UnknownHostException { + return fakeDnsLookup(); + } } private class WrappedMultinetworkPolicyTracker extends MultinetworkPolicyTracker { @@ -4021,7 +4046,7 @@ public class ConnectivityServiceTest { cellLp.addDnsServer(InetAddress.getByName("192.0.2.1")); mCellNetworkAgent.sendLinkProperties(cellLp); - mCellNetworkAgent.connect(false); + mCellNetworkAgent.connect(true); waitForIdle(); verify(mNetworkManagementService, atLeastOnce()).setDnsConfigurationForNetwork( anyInt(), mStringArrayCaptor.capture(), any(), any(), @@ -4039,9 +4064,10 @@ public class ConnectivityServiceTest { mCellNetworkAgent); CallbackInfo cbi = cellNetworkCallback.expectCallback( CallbackState.LINK_PROPERTIES, mCellNetworkAgent); - cellNetworkCallback.assertNoCallback(); assertFalse(((LinkProperties)cbi.arg).isPrivateDnsActive()); assertNull(((LinkProperties)cbi.arg).getPrivateDnsServerName()); + cellNetworkCallback.expectCallback(CallbackState.NETWORK_CAPABILITIES, mCellNetworkAgent); + cellNetworkCallback.assertNoCallback(); setPrivateDnsSettings(PRIVATE_DNS_MODE_OFF, "ignored.example.com"); verify(mNetworkManagementService, times(1)).setDnsConfigurationForNetwork( @@ -4066,14 +4092,45 @@ public class ConnectivityServiceTest { reset(mNetworkManagementService); cellNetworkCallback.assertNoCallback(); + // Strict mode. + mCellNetworkAgent.getWrappedNetworkMonitor().dnsLookupResults = new InetAddress[] { + InetAddress.getByName("2001:db8::66"), + InetAddress.getByName("192.0.2.44") + }; setPrivateDnsSettings(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME, "strict.example.com"); - // Can't test dns configuration for strict mode without properly mocking - // out the DNS lookups, but can test that LinkProperties is updated. + + // Expect a callback saying that private DNS is now in strict mode. cbi = cellNetworkCallback.expectCallback(CallbackState.LINK_PROPERTIES, mCellNetworkAgent); + LinkProperties lp = (LinkProperties) cbi.arg; + assertTrue(lp.isPrivateDnsActive()); + assertEquals("strict.example.com", lp.getPrivateDnsServerName()); cellNetworkCallback.assertNoCallback(); - assertTrue(((LinkProperties)cbi.arg).isPrivateDnsActive()); - assertEquals("strict.example.com", ((LinkProperties)cbi.arg).getPrivateDnsServerName()); + + // When the validation callback arrives, LinkProperties are updated. + // We need to wait for this callback because the test thread races with the NetworkMonitor + // thread, and if the test thread wins the race, then the times(2) verify call below will + // fail. + mService.mNetdEventCallback.onPrivateDnsValidationEvent( + mCellNetworkAgent.getNetwork().netId, "2001:db8::66", "strict.example.com", true); + cbi = cellNetworkCallback.expectCallback(CallbackState.LINK_PROPERTIES, + mCellNetworkAgent); + lp = (LinkProperties) cbi.arg; + assertTrue(lp.isPrivateDnsActive()); + assertEquals(1, lp.getValidatedPrivateDnsServers().size()); + + // setDnsConfigurationForNetwork is called twice: once when private DNS is set to strict + // mode and once when the hostname resolves. + verify(mNetworkManagementService, times(2)).setDnsConfigurationForNetwork( + anyInt(), mStringArrayCaptor.capture(), any(), any(), + eq("strict.example.com"), tlsServers.capture()); + assertEquals(2, mStringArrayCaptor.getValue().length); + assertTrue(ArrayUtils.containsAll(mStringArrayCaptor.getValue(), + new String[]{"2001:db8::1", "192.0.2.1"})); + assertEquals(2, tlsServers.getValue().length); + assertTrue(ArrayUtils.containsAll(tlsServers.getValue(), + new String[]{"2001:db8::66", "192.0.2.44"})); + reset(mNetworkManagementService); // Send the same LinkProperties and expect getting the same result including private dns. // b/118518971 @@ -4395,6 +4452,54 @@ public class ConnectivityServiceTest { mCm.unregisterNetworkCallback(defaultCallback); } + @Test + public void testVpnUnvalidated() throws Exception { + final TestNetworkCallback callback = new TestNetworkCallback(); + mCm.registerDefaultNetworkCallback(callback); + + // Enable private DNS. + setPrivateDnsSettings(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME, "strict.example.com"); + + // Bring up Ethernet. + mEthernetNetworkAgent = new MockNetworkAgent(TRANSPORT_ETHERNET); + mEthernetNetworkAgent.getWrappedNetworkMonitor().dnsLookupResults = + new InetAddress[]{ InetAddress.getByName("2001:db8::1") }; + mEthernetNetworkAgent.connect(true); + callback.expectAvailableThenValidatedCallbacks(mEthernetNetworkAgent); + callback.assertNoCallback(); + + // Bring up a VPN that has the INTERNET capability but does not provide Internet access. + final int uid = Process.myUid(); + final MockNetworkAgent vpnNetworkAgent = new MockNetworkAgent(TRANSPORT_VPN); + vpnNetworkAgent.getWrappedNetworkMonitor().gen204ProbeResult = 500; + vpnNetworkAgent.getWrappedNetworkMonitor().dnsLookupResults = null; + + final ArraySet ranges = new ArraySet<>(); + ranges.add(new UidRange(uid, uid)); + mMockVpn.setNetworkAgent(vpnNetworkAgent); + mMockVpn.setUids(ranges); + vpnNetworkAgent.connect(false /* validated */, true /* hasInternet */); + mMockVpn.connect(); + + // The VPN validates and becomes the default network for our app. + callback.expectAvailableCallbacksValidated(vpnNetworkAgent); + // TODO: this looks like a spurious callback. + callback.expectCallback(CallbackState.NETWORK_CAPABILITIES, vpnNetworkAgent); + callback.assertNoCallback(); + + assertTrue(vpnNetworkAgent.getScore() > mEthernetNetworkAgent.getScore()); + assertEquals(ConnectivityConstants.VPN_DEFAULT_SCORE, vpnNetworkAgent.getScore()); + assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork()); + + NetworkCapabilities nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork()); + assertTrue(nc.hasCapability(NET_CAPABILITY_VALIDATED)); + assertTrue(nc.hasCapability(NET_CAPABILITY_INTERNET)); + + vpnNetworkAgent.disconnect(); + callback.expectCallback(CallbackState.LOST, vpnNetworkAgent); + callback.expectAvailableCallbacksValidated(mEthernetNetworkAgent); + } + @Test public void testVpnSetUnderlyingNetworks() { final int uid = Process.myUid(); From b316f633e5c6c76e794eb71e381321dd449bde86 Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Fri, 10 May 2019 04:33:43 -0700 Subject: [PATCH 2/2] Support strict mode private DNS on VPNs that provide Internet. Currently, strict mode private DNS does not work on VPNs because NetworkMonitor does not validate VPNs. When a VPN connects, it immediately transitions to ValidatedState, skipping private DNS hostname resolution. This change makes NetworkMonitor perform private DNS hostname resolution and evaluation even on VPNs. In order to ensure that the system always immediately switches to the VPN as soon as it connects, remove the unvalidated penalty for VPN networks. This ensures that the VPN score is always 101 and the VPN always outscores other networks as soon as it connects. Previously, it would only outscore other networks when no-op validation completed. Backport of c4558228465af69d11a88eeda10d43ba48916572. Bug: 122652057 Test: atest FrameworksNetTests Test: manually ran a VPN with private DNS in strict mode Test: atest android.net.cts.ConnectivityManagerTest com.android.cts.net.HostsideVpnTests Change-Id: Iaa78a7edcf23755c89d7b354edbc28d37d74d891 Merged-In: Iaa78a7edcf23755c89d7b354edbc28d37d74d891 --- .../android/server/ConnectivityService.java | 11 +++----- .../server/connectivity/NetworkAgentInfo.java | 4 +-- .../server/ConnectivityServiceTest.java | 28 +++++++++++++++---- 3 files changed, 29 insertions(+), 14 deletions(-) diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java index 17cece1a22..b71fabae7f 100644 --- a/services/core/java/com/android/server/ConnectivityService.java +++ b/services/core/java/com/android/server/ConnectivityService.java @@ -2349,9 +2349,8 @@ public class ConnectivityService extends IConnectivityManager.Stub } } - private boolean networkRequiresValidation(NetworkAgentInfo nai) { - return NetworkMonitor.isValidationRequired( - mDefaultRequest.networkCapabilities, nai.networkCapabilities); + private boolean networkRequiresPrivateDnsValidation(NetworkAgentInfo nai) { + return nai.networkMonitor.isPrivateDnsValidationRequired(); } private void handleFreshlyValidatedNetwork(NetworkAgentInfo nai) { @@ -2369,16 +2368,14 @@ public class ConnectivityService extends IConnectivityManager.Stub for (NetworkAgentInfo nai : mNetworkAgentInfos.values()) { handlePerNetworkPrivateDnsConfig(nai, cfg); - if (networkRequiresValidation(nai)) { + if (networkRequiresPrivateDnsValidation(nai)) { handleUpdateLinkProperties(nai, new LinkProperties(nai.linkProperties)); } } } private void handlePerNetworkPrivateDnsConfig(NetworkAgentInfo nai, PrivateDnsConfig cfg) { - // Private DNS only ever applies to networks that might provide - // Internet access and therefore also require validation. - if (!networkRequiresValidation(nai)) return; + if (!networkRequiresPrivateDnsValidation(nai)) return; // Notify the NetworkMonitor thread in case it needs to cancel or // schedule DNS resolutions. If a DNS resolution is required the diff --git a/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java b/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java index 505480ea53..5ee572ecb7 100644 --- a/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java +++ b/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java @@ -432,11 +432,11 @@ public class NetworkAgentInfo implements Comparable { // down an explicitly selected network before the user gets a chance to prefer it when // a higher-scoring network (e.g., Ethernet) is available. if (networkMisc.explicitlySelected && (networkMisc.acceptUnvalidated || pretendValidated)) { - return ConnectivityConstants.MAXIMUM_NETWORK_SCORE; + return ConnectivityConstants.EXPLICITLY_SELECTED_NETWORK_SCORE; } int score = currentScore; - if (!lastValidated && !pretendValidated && !ignoreWifiUnvalidationPenalty()) { + if (!lastValidated && !pretendValidated && !ignoreWifiUnvalidationPenalty() && !isVPN()) { score -= ConnectivityConstants.UNVALIDATED_SCORE_PENALTY; } if (score < 0) score = 0; diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java index d7a64dd38d..6ceed53f4e 100644 --- a/tests/net/java/com/android/server/ConnectivityServiceTest.java +++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java @@ -26,6 +26,7 @@ import static android.net.ConnectivityManager.TYPE_MOBILE; import static android.net.ConnectivityManager.TYPE_MOBILE_FOTA; import static android.net.ConnectivityManager.TYPE_MOBILE_MMS; import static android.net.ConnectivityManager.TYPE_NONE; +import static android.net.ConnectivityManager.TYPE_VPN; import static android.net.ConnectivityManager.TYPE_WIFI; import static android.net.NetworkCapabilities.NET_CAPABILITY_CAPTIVE_PORTAL; import static android.net.NetworkCapabilities.NET_CAPABILITY_CBS; @@ -388,7 +389,7 @@ public class ConnectivityServiceTest { MockNetworkAgent(int transport, LinkProperties linkProperties) { final int type = transportToLegacyType(transport); - final String typeName = ConnectivityManager.getNetworkTypeName(transport); + final String typeName = ConnectivityManager.getNetworkTypeName(type); mNetworkInfo = new NetworkInfo(type, 0, typeName, "Mock"); mNetworkCapabilities = new NetworkCapabilities(); mNetworkCapabilities.addTransportType(transport); @@ -1111,6 +1112,8 @@ public class ConnectivityServiceTest { return TYPE_WIFI; case TRANSPORT_CELLULAR: return TYPE_MOBILE; + case TRANSPORT_VPN: + return TYPE_VPN; default: return TYPE_NONE; } @@ -4468,7 +4471,7 @@ public class ConnectivityServiceTest { callback.expectAvailableThenValidatedCallbacks(mEthernetNetworkAgent); callback.assertNoCallback(); - // Bring up a VPN that has the INTERNET capability but does not provide Internet access. + // Bring up a VPN that has the INTERNET capability but does not validate. final int uid = Process.myUid(); final MockNetworkAgent vpnNetworkAgent = new MockNetworkAgent(TRANSPORT_VPN); vpnNetworkAgent.getWrappedNetworkMonitor().gen204ProbeResult = 500; @@ -4481,8 +4484,8 @@ public class ConnectivityServiceTest { vpnNetworkAgent.connect(false /* validated */, true /* hasInternet */); mMockVpn.connect(); - // The VPN validates and becomes the default network for our app. - callback.expectAvailableCallbacksValidated(vpnNetworkAgent); + // Even though the VPN is unvalidated, it becomes the default network for our app. + callback.expectAvailableCallbacksUnvalidated(vpnNetworkAgent); // TODO: this looks like a spurious callback. callback.expectCallback(CallbackState.NETWORK_CAPABILITIES, vpnNetworkAgent); callback.assertNoCallback(); @@ -4492,9 +4495,24 @@ public class ConnectivityServiceTest { assertEquals(vpnNetworkAgent.getNetwork(), mCm.getActiveNetwork()); NetworkCapabilities nc = mCm.getNetworkCapabilities(vpnNetworkAgent.getNetwork()); - assertTrue(nc.hasCapability(NET_CAPABILITY_VALIDATED)); + assertFalse(nc.hasCapability(NET_CAPABILITY_VALIDATED)); assertTrue(nc.hasCapability(NET_CAPABILITY_INTERNET)); + assertFalse(vpnNetworkAgent.getWrappedNetworkMonitor().isValidationRequired()); + assertTrue(vpnNetworkAgent.getWrappedNetworkMonitor().isPrivateDnsValidationRequired()); + + // Pretend that the strict mode private DNS hostname now resolves. Even though the + // connectivity probe still returns 500, the network validates because the connectivity + // probe is not used on VPNs. + vpnNetworkAgent.getWrappedNetworkMonitor().dnsLookupResults = + new InetAddress[]{ InetAddress.getByName("2001:db8::1") }; + mCm.reportNetworkConnectivity(vpnNetworkAgent.getNetwork(), true); + + // Expect to see the validated capability, but no other changes, because the VPN is already + // the default network for the app. + callback.expectCapabilitiesWith(NET_CAPABILITY_VALIDATED, vpnNetworkAgent); + callback.assertNoCallback(); + vpnNetworkAgent.disconnect(); callback.expectCallback(CallbackState.LOST, vpnNetworkAgent); callback.expectAvailableCallbacksValidated(mEthernetNetworkAgent);