Merge "ResolverTest: add GetAddrInfoV4V6_MultiAnswers"

                                 kHelloExampleComAddrV6_TEREDO, kHelloExampleComAddrV6_IPV4COMPAT));

}

TEST_F(ResolverTest, GetAddrInfoV4V6_MultiAnswers) {

    test::DNSResponder dns(test::DNSResponder::MappingType::BINARY_PACKET);

    // Use one IPv4 address only because we can't control IPv4 address ordering in this test

    // which uses a fake network.

    dns.addMappingBinaryPacket(kHelloExampleComQueryV4, kHelloExampleComResponseV4);

    dns.addMappingBinaryPacket(kHelloExampleComQueryV6, kHelloExampleComResponsesV6);

    StartDns(dns, {});

    ASSERT_TRUE(mDnsClient.SetResolversForNetwork());

    addrinfo hints = {.ai_family = AF_UNSPEC, .ai_socktype = SOCK_DGRAM};

    ScopedAddrinfo result = safe_getaddrinfo(kHelloExampleCom, nullptr, &hints);

    ASSERT_FALSE(result == nullptr);

    // Expect the DNS result order is ipv6 global unicast address, IPv4 address, IPv6 teredo

    // tunneling address and IPv4-compatible IPv6 address because of the precedence comparison

    // of RFC 6724.

    //

    // The reason is here for the sorting result from _rfc6724_compare.

    // For rule 1: avoid unusable destinations, all addresses are unusable on a fake test network.

    // For rule 2: prefer matching scope, all addresses don't match because of no source address.

    //             See rule#1 as well.

    // (rule 3 is not implemented)

    // (rule 4 is not implemented)

    // For rule 5: prefer matching label, the source address is not valid and can't match the dns

    //             reply addresses. See rule#1 as well.

    // For rule 6: prefer higher precedence, sorted by the order: gua(40), ipv4(35), teredo(5) and

    //             ipv4-compatible(1).

    // Ignore from rule 7 to rule 10 because the results has been sorted by rule 6.

    //

    // See _get_precedence, _rfc6724_compare in packages/modules/DnsResolver/getaddrinfo.cpp

    EXPECT_THAT(

            ToStrings(result),

            testing::ElementsAre(kHelloExampleComAddrV6_GUA, kHelloExampleComAddrV4,

                                 kHelloExampleComAddrV6_TEREDO, kHelloExampleComAddrV6_IPV4COMPAT));

    hints = {.ai_family = AF_UNSPEC};

    result = safe_getaddrinfo(kHelloExampleCom, nullptr, &hints);

    ASSERT_FALSE(result == nullptr);

    // The results are sorted in every querying by explore_options and then concatenates all sorted

    // results. resolv_getaddrinfo() calls explore_fqdn() many times by the different

    // explore_options. It means that resolv_rfc6724_sort() only sorts the ordering in the results

    // of each explore_options and concatenates all sorted results into one link list. The address

    // order of the output addrinfo is:

    //   2404:6800::5175:15ca (socktype=2, protocol=17) ->

    //   1.2.3.4 (socktype=2, protocol=17) ->

    //   2001::47c1 (socktype=2, protocol=17) ->

    //   ::1.2.3.4 (socktype=2, protocol=17) ->

    //   2404:6800::5175:15ca (socktype=1, protocol=6) ->

    //   1.2.3.4 (socktype=1, protocol=6) ->

    //   2001::47c1 (socktype=1, protocol=6) ->

    //   ::1.2.3.4 (socktype=1, protocol=6)

    //

    // See resolv_getaddrinfo, explore_fqdn and dns_getaddrinfo.

    EXPECT_THAT(

            ToStrings(result),

            testing::ElementsAre(kHelloExampleComAddrV6_GUA, kHelloExampleComAddrV4,

                                 kHelloExampleComAddrV6_TEREDO, kHelloExampleComAddrV6_IPV4COMPAT,

                                 kHelloExampleComAddrV6_GUA, kHelloExampleComAddrV4,

                                 kHelloExampleComAddrV6_TEREDO, kHelloExampleComAddrV6_IPV4COMPAT));

}

TEST_F(ResolverTest, GetAddrInfo_cnames) {

    constexpr char host_name[] = "host.example.com.";

    test::DNSResponder dns;