Merge "Add skip_4a_query_on_v6_linklocal_addr flag" (2f40edc2) · Commits · e / os / android_packages_modules_DnsResolver

Experiments.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,7 @@ class Experiments {
		"parallel_lookup_sleep_time",
		"retransmission_time_interval",
		"retry_count",
		"skip_4a_query_on_v6_linklocal_addr",
		"sort_nameservers",
		};
		// This value is used in updateInternal as the default value if any flags can't be found.

getaddrinfo.cpp

+3 −1

Original line number	Diff line number	Diff line
		@@ -67,6 +67,7 @@

		#define ANY 0

		using android::net::Experiments;
		using android::net::NetworkDnsEventReported;

		const char in_addrany[] = {0, 0, 0, 0};
		@@ -1312,7 +1313,8 @@ static int _find_src_addr(const struct sockaddr* addr, struct sockaddr* src_addr
		return -1;
		}

		if (src_addr->sa_family == AF_INET6) {
		if (Experiments::getInstance()->getFlag("skip_4a_query_on_v6_linklocal_addr", 1) &&
		src_addr->sa_family == AF_INET6) {
		sockaddr_in6* sin6 = reinterpret_cast<sockaddr_in6*>(src_addr);
		if (!allow_v6_linklocal && IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
		return 0;

tests/resolv_integration_test.cpp

+42 −0

Original line number	Diff line number	Diff line
		@@ -7666,6 +7666,48 @@ TEST_F(ResolverMultinetworkTest, IPv6LinkLocalWithDefaultRoute) {
		EXPECT_EQ(GetNumQueriesForType(*dnsPair->dnsServer, ns_type::ns_t_aaaa, host_name), 1U);
		}

		// Test if the "do not send AAAA query when IPv6 address is link-local with a default route" feature
		// can be toggled by flag.
		TEST_F(ResolverMultinetworkTest, IPv6LinkLocalWithDefaultRouteFlag) {
		constexpr char host_name[] = "ohayou.example.com.";
		const struct TestConfig {
		std::string flagValue;
		std::vector<std::string> ips;
		unsigned numOfQuadAQuery;
		} TestConfigs[]{{"0", {"192.0.2.0", "2001:db8:cafe:d00d::31"}, 1U}, {"1", {"192.0.2.0"}, 0U}};

		for (const auto& config : TestConfigs) {
		SCOPED_TRACE(fmt::format("flagValue = {}, numOfQuadAQuery = {}", config.flagValue,
		config.numOfQuadAQuery));

		ScopedSystemProperties sp1(kSkip4aQueryOnV6LinklocalAddrFlag, config.flagValue);
		ScopedPhysicalNetwork network = CreateScopedPhysicalNetwork(ConnectivityType::V4);
		ASSERT_RESULT_OK(network.init());

		// Add IPv6 default route
		ASSERT_TRUE(mDnsClient.netdService()
		->networkAddRoute(network.netId(), network.ifname(), "::/0", "")
		.isOk());

		const Result<DnsServerPair> dnsPair = network.addIpv4Dns();
		ASSERT_RESULT_OK(dnsPair);
		StartDns(*dnsPair->dnsServer, {{host_name, ns_type::ns_t_a, "192.0.2.0"},
		{host_name, ns_type::ns_t_aaaa, "2001:db8:cafe:d00d::31"}});

		ASSERT_TRUE(network.setDnsConfiguration());
		ASSERT_TRUE(network.startTunForwarder());

		auto result = android_getaddrinfofornet_wrapper(host_name, network.netId());
		ASSERT_RESULT_OK(result);
		ScopedAddrinfo ai_results(std::move(result.value()));
		std::vector<std::string> result_strs = ToStrings(ai_results);
		EXPECT_THAT(result_strs, testing::UnorderedElementsAreArray(config.ips));
		EXPECT_EQ(GetNumQueriesForType(*dnsPair->dnsServer, ns_type::ns_t_a, host_name), 1U);
		EXPECT_EQ(GetNumQueriesForType(*dnsPair->dnsServer, ns_type::ns_t_aaaa, host_name),
		config.numOfQuadAQuery);
		}
		}

		// v6 mdns is expected to be sent when the IPv6 address is a link-local with a default route.
		TEST_F(ResolverMultinetworkTest, MdnsIPv6LinkLocalWithDefaultRoute) {
		// Kernel 4.4 does not provide an IPv6 link-local address when an interface is added to a

tests/resolv_test_utils.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -140,6 +140,8 @@ const std::string kDotValidationLatencyOffsetMsFlag(kFlagPrefix +
		"dot_validation_latency_offset_ms");
		const std::string kRetransIntervalFlag(kFlagPrefix + "retransmission_time_interval");
		const std::string kRetryCountFlag(kFlagPrefix + "retry_count");
		const std::string kSkip4aQueryOnV6LinklocalAddrFlag(kFlagPrefix +
		"skip_4a_query_on_v6_linklocal_addr");
		const std::string kSortNameserversFlag(kFlagPrefix + "sort_nameservers");

		static constexpr char kLocalHost[] = "localhost";