Merge "Support strict mode private DNS on VPNs that provide Internet." (a56eab41) · Commits · e / os / android_frameworks_base

packages/NetworkStack/src/com/android/server/connectivity/NetworkMonitor.java

+17 −3

Original line number	Diff line number	Diff line
		@@ -520,6 +520,9 @@ public class NetworkMonitor extends StateMachine {
		return NetworkMonitorUtils.isValidationRequired(mNetworkCapabilities);
		}

		private boolean isPrivateDnsValidationRequired() {
		return NetworkMonitorUtils.isPrivateDnsValidationRequired(mNetworkCapabilities);
		}

		private void notifyNetworkTested(int result, @Nullable String redirectUrl) {
		try {
		@@ -607,7 +610,7 @@ public class NetworkMonitor extends StateMachine {
		return HANDLED;
		case CMD_PRIVATE_DNS_SETTINGS_CHANGED: {
		final PrivateDnsConfig cfg = (PrivateDnsConfig) message.obj;
		if (!isValidationRequired() \|\| cfg == null \|\| !cfg.inStrictMode()) {
		if (!isPrivateDnsValidationRequired() \|\| cfg == null \|\| !cfg.inStrictMode()) {
		// No DNS resolution required.
		//
		// We don't force any validation in opportunistic mode
		@@ -843,9 +846,20 @@ public class NetworkMonitor extends StateMachine {
		// the network so don't bother validating here. Furthermore sending HTTP
		// packets over the network may be undesirable, for example an extremely
		// expensive metered network, or unwanted leaking of the User Agent string.
		//
		// On networks that need to support private DNS in strict mode (e.g., VPNs, but
		// not networks that don't provide Internet access), we still need to perform
		// private DNS server resolution.
		if (!isValidationRequired()) {
		validationLog("Network would not satisfy default request, not validating");
		if (isPrivateDnsValidationRequired()) {
		validationLog("Network would not satisfy default request, "
		+ "resolving private DNS");
		transitionTo(mEvaluatingPrivateDnsState);
		} else {
		validationLog("Network would not satisfy default request, "
		+ "not validating");
		transitionTo(mValidatedState);
		}
		return HANDLED;
		}
		mEvaluateAttempts++;

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

+5 −5

Original line number	Diff line number	Diff line
		@@ -40,7 +40,7 @@ import static android.net.NetworkCapabilities.NET_CAPABILITY_VALIDATED;
		import static android.net.NetworkCapabilities.TRANSPORT_VPN;
		import static android.net.NetworkPolicyManager.RULE_NONE;
		import static android.net.NetworkPolicyManager.uidRulesToString;
		import static android.net.shared.NetworkMonitorUtils.isValidationRequired;
		import static android.net.shared.NetworkMonitorUtils.isPrivateDnsValidationRequired;
		import static android.os.Process.INVALID_UID;
		import static android.system.OsConstants.IPPROTO_TCP;
		import static android.system.OsConstants.IPPROTO_UDP;
		@@ -2824,8 +2824,8 @@ public class ConnectivityService extends IConnectivityManager.Stub
		}
		}

		private boolean networkRequiresValidation(NetworkAgentInfo nai) {
		return isValidationRequired(nai.networkCapabilities);
		private boolean networkRequiresPrivateDnsValidation(NetworkAgentInfo nai) {
		return isPrivateDnsValidationRequired(nai.networkCapabilities);
		}

		private void handleFreshlyValidatedNetwork(NetworkAgentInfo nai) {
		@@ -2843,7 +2843,7 @@ 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));
		}
		}
		@@ -2852,7 +2852,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
		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 NetworkAgentInfo/NetworkMonitor in case NetworkMonitor needs to cancel or
		// schedule DNS resolutions. If a DNS resolution is required the

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

+1 −1

Original line number	Diff line number	Diff line
		@@ -29,7 +29,7 @@ public class ConnectivityConstants {
		//
		// This ensures that a) the explicitly selected network is never trumped by anything else, and
		// b) the explicitly selected network is never torn down.
		public static final int MAXIMUM_NETWORK_SCORE = 100;
		public static final int EXPLICITLY_SELECTED_NETWORK_SCORE = 100;
		// VPNs typically have priority over other networks. Give them a score that will
		// let them win every single time.
		public static final int VPN_DEFAULT_SCORE = 101;

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

+2 −2

Original line number	Diff line number	Diff line
		@@ -483,11 +483,11 @@ public class NetworkAgentInfo implements Comparable<NetworkAgentInfo> {
		// 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;

services/net/java/android/net/shared/NetworkMonitorUtils.java

+12 −5

Original line number	Diff line number	Diff line
		@@ -43,16 +43,23 @@ public class NetworkMonitorUtils {
		"android.permission.ACCESS_NETWORK_CONDITIONS";

		/**
		* Return whether validation is required for a network.
		* @param dfltNetCap Default requested network capabilities.
		* Return whether validation is required for private DNS in strict mode.
		* @param nc Network capabilities of the network to test.
		*/
		public static boolean isValidationRequired(NetworkCapabilities nc) {
		public static boolean isPrivateDnsValidationRequired(NetworkCapabilities nc) {
		// TODO: Consider requiring validation for DUN networks.
		return nc != null
		&& nc.hasCapability(NET_CAPABILITY_INTERNET)
		&& nc.hasCapability(NET_CAPABILITY_NOT_RESTRICTED)
		&& nc.hasCapability(NET_CAPABILITY_TRUSTED)
		&& nc.hasCapability(NET_CAPABILITY_NOT_VPN);
		&& nc.hasCapability(NET_CAPABILITY_TRUSTED);
		}

		/**
		* Return whether validation is required for a network.
		* @param nc Network capabilities of the network to test.
		*/
		public static boolean isValidationRequired(NetworkCapabilities nc) {
		// TODO: Consider requiring validation for DUN networks.
		return isPrivateDnsValidationRequired(nc) && nc.hasCapability(NET_CAPABILITY_NOT_VPN);
		}
		}