Skip res_doh_send() if there is no validated DoH servers am: 9b748ee32c (8570d545) · Commits · e / os / android_packages_modules_DnsResolver

PrivateDnsConfiguration.cpp

+13 −3

Original line number	Diff line number	Diff line
		@@ -109,7 +109,11 @@ int PrivateDnsConfiguration::set(int32_t netId, uint32_t mark,
		}

		PrivateDnsStatus PrivateDnsConfiguration::getStatus(unsigned netId) const {
		PrivateDnsStatus status{PrivateDnsMode::OFF, {}};
		PrivateDnsStatus status{
		.mode = PrivateDnsMode::OFF,
		.dotServersMap = {},
		.dohServersMap = {},
		};
		std::lock_guard guard(mPrivateDnsLock);

		const auto mode = mPrivateDnsModes.find(netId);
		@@ -121,10 +125,16 @@ PrivateDnsStatus PrivateDnsConfiguration::getStatus(unsigned netId) const {
		for (const auto& [_, server] : netPair->second) {
		if (server->isDot() && server->active()) {
		DnsTlsServer& dotServer = static_cast<DnsTlsServer>(server.get());
		status.serversMap.emplace(dotServer, server->validationState());
		status.dotServersMap.emplace(dotServer, server->validationState());
		}
		}
		// TODO: also add DoH server to the map.
		}

		auto it = mDohTracker.find(netId);
		if (it != mDohTracker.end()) {
		status.dohServersMap.emplace(
		netdutils::IPSockAddr::toIPSockAddr(it->second.ipAddr, kDohPort),
		it->second.status);
		}

		return status;

PrivateDnsConfiguration.h

+13 −2

Original line number	Diff line number	Diff line
		@@ -44,18 +44,29 @@ struct PrivateDnsStatus {
		PrivateDnsMode mode;

		// TODO: change the type to std::vector<DnsTlsServer>.
		std::map<DnsTlsServer, Validation, AddressComparator> serversMap;
		std::map<DnsTlsServer, Validation, AddressComparator> dotServersMap;

		std::map<netdutils::IPSockAddr, Validation> dohServersMap;

		std::list<DnsTlsServer> validatedServers() const {
		std::list<DnsTlsServer> servers;

		for (const auto& pair : serversMap) {
		for (const auto& pair : dotServersMap) {
		if (pair.second == Validation::success) {
		servers.push_back(pair.first);
		}
		}
		return servers;
		}

		bool hasValidatedDohServers() const {
		for (const auto& [_, status] : dohServersMap) {
		if (status == Validation::success) {
		return true;
		}
		}
		return false;
		}
		};

		class PrivateDnsConfiguration {

PrivateDnsConfigurationTest.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -110,7 +110,7 @@ class PrivateDnsConfigurationTest : public ::testing::Test {
		if (status.mode != mode) return false;

		std::map<std::string, Validation> serverStateMap;
		for (const auto& [server, validation] : status.serversMap) {
		for (const auto& [server, validation] : status.dotServersMap) {
		serverStateMap[ToString(&server.ss)] = validation;
		}
		return (serverStateMap == mObserver.getServerStateMap());
		@@ -275,7 +275,7 @@ TEST_F(PrivateDnsConfigurationTest, NoValidation) {
		const auto expectStatus = [&]() {
		const PrivateDnsStatus status = mPdc.getStatus(kNetId);
		EXPECT_EQ(status.mode, PrivateDnsMode::OFF);
		EXPECT_THAT(status.serversMap, testing::IsEmpty());
		EXPECT_THAT(status.dotServersMap, testing::IsEmpty());
		};

		EXPECT_EQ(mPdc.set(kNetId, kMark, {"invalid_addr"}, {}, {}), -EINVAL);

ResolverController.cpp

+4 −4

Original line number	Diff line number	Diff line
		@@ -268,7 +268,7 @@ int ResolverController::getResolverInfo(int32_t netId, std::vector<std::string>*
		ResolverStats::encodeAll(res_stats, stats);

		const auto privateDnsStatus = PrivateDnsConfiguration::getInstance().getStatus(netId);
		for (const auto& [server, _] : privateDnsStatus.serversMap) {
		for (const auto& [server, _] : privateDnsStatus.dotServersMap) {
		tlsServers->push_back(server.toIpString());
		}

		@@ -362,13 +362,13 @@ void ResolverController::dump(DumpWriter& dw, unsigned netId) {
		mDns64Configuration.dump(dw, netId);
		const auto privateDnsStatus = PrivateDnsConfiguration::getInstance().getStatus(netId);
		dw.println("Private DNS mode: %s", getPrivateDnsModeString(privateDnsStatus.mode));
		if (privateDnsStatus.serversMap.size() == 0) {
		if (privateDnsStatus.dotServersMap.size() == 0) {
		dw.println("No Private DNS servers configured");
		} else {
		dw.println("Private DNS configuration (%u entries)",
		static_cast<uint32_t>(privateDnsStatus.serversMap.size()));
		static_cast<uint32_t>(privateDnsStatus.dotServersMap.size()));
		dw.incIndent();
		for (const auto& [server, validation] : privateDnsStatus.serversMap) {
		for (const auto& [server, validation] : privateDnsStatus.dotServersMap) {
		dw.println("%s name{%s} status{%s}", server.toIpString().c_str(),
		server.name.c_str(), validationStatusToString(validation));
		}

res_send.cpp

+12 −8

Original line number	Diff line number	Diff line
		@@ -1337,7 +1337,7 @@ static int res_private_dns_send(ResState* statp, const Slice query, const Slice
		}
		case PrivateDnsMode::OPPORTUNISTIC: {
		*fallback = true;
		if (enableDoH) {
		if (enableDoH && privateDnsStatus.hasValidatedDohServers()) {
		result = res_doh_send(statp, query, answer, rcode);
		if (result != DOH_RESULT_CAN_NOT_SEND) return result;
		}
		@@ -1346,7 +1346,7 @@ static int res_private_dns_send(ResState* statp, const Slice query, const Slice
		}
		case PrivateDnsMode::STRICT: {
		*fallback = false;
		if (enableDoH) {
		if (enableDoH && privateDnsStatus.hasValidatedDohServers()) {
		result = res_doh_send(statp, query, answer, rcode);
		if (result != DOH_RESULT_CAN_NOT_SEND) return result;
		}
		@@ -1366,15 +1366,19 @@ static int res_private_dns_send(ResState* statp, const Slice query, const Slice
		// default network change.
		for (int i = 0; i < 42; i++) {
		std::this_thread::sleep_for(std::chrono::milliseconds(100));
		if (enableDoH) {
		result = res_doh_send(statp, query, answer, rcode);
		if (result != DOH_RESULT_CAN_NOT_SEND) return result;
		}

		// Calling getStatus() to merely check if there's any validated server seems
		// wasteful. Consider adding a new method in PrivateDnsConfiguration for speed
		// ups.
		if (!privateDnsConfiguration.getStatus(netId).validatedServers().empty()) {
		privateDnsStatus = privateDnsConfiguration.getStatus(netId);

		if (enableDoH && privateDnsStatus.hasValidatedDohServers()) {
		result = res_doh_send(statp, query, answer, rcode);
		if (result != DOH_RESULT_CAN_NOT_SEND) return result;
		}

		// Switch to use the DoT servers if they are validated.
		if (!privateDnsStatus.validatedServers().empty()) {
		break;
		}
		}