c-ares/test/ares-test-mock-ai.cc

/* MIT License
 *
 * Copyright (c) The c-ares project and its contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * SPDX-License-Identifier: MIT
 */
#include "ares-test-ai.h"
#include "dns-proto.h"

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include <sstream>
#include <vector>

using testing::InvokeWithoutArgs;
using testing::DoAll;

namespace ares {
namespace test {

MATCHER_P(IncludesNumAddresses, n, "") {
  (void)result_listener;
  if(!arg)
    return false;
  int cnt = 0;
  for (const ares_addrinfo_node* ai = arg->nodes; ai != NULL; ai = ai->ai_next)
    cnt++;
  return n == cnt;
}

MATCHER_P(IncludesV4Address, address, "") {
  (void)result_listener;
  if(!arg)
    return false;
  in_addr addressnum = {};
  if (!ares_inet_pton(AF_INET, address, &addressnum))
    return false; // wrong number format?
  for (const ares_addrinfo_node* ai = arg->nodes; ai != NULL; ai = ai->ai_next) {
    if (ai->ai_family != AF_INET)
      continue;
    if (ai->ai_addrlen != sizeof(struct sockaddr_in))
      continue;
    if (reinterpret_cast<sockaddr_in*>(ai->ai_addr)->sin_addr.s_addr ==
        addressnum.s_addr)
      return true; // found
  }
  return false;
}

MATCHER_P(IncludesV6Address, address, "") {
  (void)result_listener;
  if(!arg)
    return false;
  in6_addr addressnum = {};
  if (!ares_inet_pton(AF_INET6, address, &addressnum)) {
    return false; // wrong number format?
  }
  for (const ares_addrinfo_node* ai = arg->nodes; ai != NULL; ai = ai->ai_next) {
    if (ai->ai_family != AF_INET6)
      continue;
    if (ai->ai_addrlen != sizeof(struct sockaddr_in6))
      continue;
    if (!memcmp(
        reinterpret_cast<sockaddr_in6*>(ai->ai_addr)->sin6_addr.s6_addr,
        addressnum.s6_addr, sizeof(addressnum.s6_addr)))
      return true; // found
  }
  return false;
}

// UDP only so mock server doesn't get confused by concatenated requests
TEST_P(MockUDPChannelTestAI, GetAddrInfoParallelLookups) {
  DNSPacket rsp1;
  rsp1.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A))
    .add_answer(new DNSARR("www.google.com", 100, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp1));
  DNSPacket rsp2;
  rsp2.set_response().set_aa()
    .add_question(new DNSQuestion("www.example.com", T_A))
    .add_answer(new DNSARR("www.example.com", 100, {1, 2, 3, 4}));
  ON_CALL(server_, OnRequest("www.example.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp2));

  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  AddrInfoResult result1;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result1);
  AddrInfoResult result2;
  ares_getaddrinfo(channel_, "www.example.com.", NULL, &hints, AddrInfoCallback, &result2);
  AddrInfoResult result3;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result3);
  Process();

  EXPECT_TRUE(result1.done_);
  EXPECT_EQ(result1.status_, ARES_SUCCESS);
  EXPECT_THAT(result1.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result1.ai_, IncludesV4Address("2.3.4.5"));

  EXPECT_TRUE(result2.done_);
  EXPECT_EQ(result2.status_, ARES_SUCCESS);
  EXPECT_THAT(result2.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result2.ai_, IncludesV4Address("1.2.3.4"));

  EXPECT_TRUE(result3.done_);
  EXPECT_EQ(result3.status_, ARES_SUCCESS);
  EXPECT_THAT(result3.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result3.ai_, IncludesV4Address("2.3.4.5"));
}

// UDP to TCP specific test
TEST_P(MockUDPChannelTestAI, TruncationRetry) {
  DNSPacket rsptruncated;
  rsptruncated.set_response().set_aa().set_tc()
    .add_question(new DNSQuestion("www.google.com", T_A));
  DNSPacket rspok;
  rspok.set_response()
    .add_question(new DNSQuestion("www.google.com", T_A))
    .add_answer(new DNSARR("www.google.com", 100, {1, 2, 3, 4}));
  EXPECT_CALL(server_, OnRequest("www.google.com", T_A))
    .WillOnce(SetReply(&server_, &rsptruncated))
    .WillOnce(SetReply(&server_, &rspok));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(result.status_, ARES_SUCCESS);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("1.2.3.4"));
}

TEST_P(MockTCPChannelTestAI, MalformedResponse) {
  std::vector<byte> one = {0x01};
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReplyData(&server_, one));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ETIMEOUT, result.status_);
}

TEST_P(MockTCPChannelTestAI, FormErrResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(FORMERR);
  EXPECT_CALL(server_, OnRequest("www.google.com", T_A))
    .WillOnce(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_EFORMERR, result.status_);
}

TEST_P(MockTCPChannelTestAI, ServFailResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(SERVFAIL);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ESERVFAIL, result.status_);
}

TEST_P(MockTCPChannelTestAI, NotImplResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(NOTIMP);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ENOTIMP, result.status_);
}

TEST_P(MockTCPChannelTestAI, RefusedResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(REFUSED);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_EREFUSED, result.status_);
}

TEST_P(MockTCPChannelTestAI, YXDomainResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(YXDOMAIN);
  EXPECT_CALL(server_, OnRequest("www.google.com", T_A))
    .WillOnce(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ENODATA, result.status_);
}

class MockExtraOptsTestAI
    : public MockChannelOptsTest,
      public ::testing::WithParamInterface< std::pair<int, bool> > {
 public:
  MockExtraOptsTestAI()
    : MockChannelOptsTest(1, GetParam().first, GetParam().second,
                          FillOptions(&opts_),
                          ARES_OPT_SOCK_SNDBUF|ARES_OPT_SOCK_RCVBUF) {}
  static struct ares_options* FillOptions(struct ares_options * opts) {
    memset(opts, 0, sizeof(struct ares_options));
    // Set a few options that affect socket communications
    opts->socket_send_buffer_size = 514;
    opts->socket_receive_buffer_size = 514;
    return opts;
  }
 private:
  struct ares_options opts_;
};

TEST_P(MockExtraOptsTestAI, SimpleQuery) {
  ares_set_local_ip4(channel_, 0x7F000001);
  byte addr6[16] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
  ares_set_local_ip6(channel_, addr6);
  ares_set_local_dev(channel_, "dummy");

  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A))
    .add_answer(new DNSARR("www.google.com", 100, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_SUCCESS, result.status_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
}

class MockExtraOptsNDotsTestAI
    : public MockChannelOptsTest,
      public ::testing::WithParamInterface< std::pair<int, bool> > {
 public:
  MockExtraOptsNDotsTestAI(int ndots)
    : MockChannelOptsTest(1, GetParam().first, GetParam().second,
                          FillOptions(&opts_, ndots),
                          ARES_OPT_SOCK_SNDBUF|ARES_OPT_SOCK_RCVBUF|ARES_OPT_NDOTS) {}
  static struct ares_options* FillOptions(struct ares_options * opts, int ndots) {
    memset(opts, 0, sizeof(struct ares_options));
    // Set a few options that affect socket communications
    opts->socket_send_buffer_size = 514;
    opts->socket_receive_buffer_size = 514;
    opts->ndots = ndots;
    return opts;
  }
 private:
  struct ares_options opts_;
};

class MockExtraOptsNDots5TestAI : public MockExtraOptsNDotsTestAI {
 public:
  MockExtraOptsNDots5TestAI() : MockExtraOptsNDotsTestAI(5) {}
};

TEST_P(MockExtraOptsNDots5TestAI, SimpleQuery) {
  ares_set_local_ip4(channel_, 0x7F000001);
  byte addr6[16] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
  ares_set_local_ip6(channel_, addr6);
  ares_set_local_dev(channel_, "dummy");

  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("dynamodb.us-east-1.amazonaws.com", T_A))
    .add_answer(new DNSARR("dynamodb.us-east-1.amazonaws.com", 100, {123, 45, 67, 8}));
  ON_CALL(server_, OnRequest("dynamodb.us-east-1.amazonaws.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "dynamodb.us-east-1.amazonaws.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_SUCCESS, result.status_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("123.45.67.8"));
}

class MockExtraOptsNDots0TestAI : public MockExtraOptsNDotsTestAI {
 public:
  MockExtraOptsNDots0TestAI() : MockExtraOptsNDotsTestAI(0) {}
};

TEST_P(MockExtraOptsNDots0TestAI, SimpleQuery) {
  DNSPacket rsp_ndots0;
  rsp_ndots0.set_response().set_aa()
    .add_question(new DNSQuestion("ndots0", T_A))
    .add_answer(new DNSARR("ndots0", 100, {1, 2, 3, 4}));
  ON_CALL(server_, OnRequest("ndots0", T_A))
    .WillByDefault(SetReply(&server_, &rsp_ndots0));

  DNSPacket rsp_ndots0_first;
  rsp_ndots0_first.set_response().set_aa()
    .add_question(new DNSQuestion("ndots0.first.com", T_A))
    .add_answer(new DNSARR("ndots0.first.com", 100, {99, 99, 99, 99}));
  ON_CALL(server_, OnRequest("ndots0.first.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp_ndots0_first));

  DNSPacket rsp_ndots0_second;
  rsp_ndots0_second.set_response().set_aa()
    .add_question(new DNSQuestion("ndots0.second.org", T_A))
    .add_answer(new DNSARR("ndots0.second.org", 100, {98, 98, 98, 98}));
  ON_CALL(server_, OnRequest("ndots0.second.org", T_A))
    .WillByDefault(SetReply(&server_, &rsp_ndots0_second));

  DNSPacket rsp_ndots0_third;
  rsp_ndots0_third.set_response().set_aa()
    .add_question(new DNSQuestion("ndots0.third.gov", T_A))
    .add_answer(new DNSARR("ndots0.third.gov", 100, {97, 97, 97, 97}));
  ON_CALL(server_, OnRequest("ndots0.third.gov", T_A))
    .WillByDefault(SetReply(&server_, &rsp_ndots0_third));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "ndots0", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_SUCCESS, result.status_);
  std::stringstream ss;
  ss << result.ai_;
  EXPECT_EQ("{addr=[1.2.3.4]}", ss.str());
}

class MockFlagsChannelOptsTestAI
    : public MockChannelOptsTest,
      public ::testing::WithParamInterface< std::pair<int, bool> > {
 public:
  MockFlagsChannelOptsTestAI(int flags)
    : MockChannelOptsTest(1, GetParam().first, GetParam().second,
                          FillOptions(&opts_, flags), ARES_OPT_FLAGS) {}
  static struct ares_options* FillOptions(struct ares_options * opts, int flags) {
    memset(opts, 0, sizeof(struct ares_options));
    opts->flags = flags;
    return opts;
  }
 private:
  struct ares_options opts_;
};

class MockNoCheckRespChannelTestAI : public MockFlagsChannelOptsTestAI {
 public:
  MockNoCheckRespChannelTestAI() : MockFlagsChannelOptsTestAI(ARES_FLAG_NOCHECKRESP) {}
};

TEST_P(MockNoCheckRespChannelTestAI, ServFailResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(SERVFAIL);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ESERVFAIL, result.status_);
}

TEST_P(MockNoCheckRespChannelTestAI, NotImplResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(NOTIMP);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ENOTIMP, result.status_);
}

TEST_P(MockNoCheckRespChannelTestAI, RefusedResponse) {
  DNSPacket rsp;
  rsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.google.com", T_A));
  rsp.set_rcode(REFUSED);
  ON_CALL(server_, OnRequest("www.google.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_EREFUSED, result.status_);
}

TEST_P(MockChannelTestAI, FamilyV6) {
  DNSPacket rsp6;
  rsp6.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_AAAA))
    .add_answer(new DNSAaaaRR("example.com", 100,
                              {0x21, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                               0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x03}));
  ON_CALL(server_, OnRequest("example.com", T_AAAA))
    .WillByDefault(SetReply(&server_, &rsp6));
  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET6;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "example.com.", NULL, &hints,
                   AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV6Address("2121:0000:0000:0000:0000:0000:0000:0303"));
}

// Test case for Issue #662
TEST_P(MockChannelTestAI, PartialQueryCancel) {
  std::vector<byte> nothing;
  DNSPacket reply;
  reply.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_A))
    .add_answer(new DNSARR("example.com", 0x0100, {0x01, 0x02, 0x03, 0x04}));

  ON_CALL(server_, OnRequest("example.com", T_A))
    .WillByDefault(SetReply(&server_, &reply));

  ON_CALL(server_, OnRequest("example.com", T_AAAA))
    .WillByDefault(SetReplyData(&server_, nothing));


  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_UNSPEC;
  ares_getaddrinfo(channel_, "example.com.", NULL, &hints,
                   AddrInfoCallback, &result);

  // After 100ms, issues ares_cancel(), this should be enough time for the A
  // record reply, but before the timeout on the AAAA record.
  Process(100);
  EXPECT_TRUE(result.done_);
  EXPECT_EQ(ARES_ECANCELLED, result.status_);
}

TEST_P(MockChannelTestAI, FamilyV4) {
  DNSPacket rsp4;
  rsp4.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_A))
    .add_answer(new DNSARR("example.com", 100, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("example.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp4));
  AddrInfoResult result = {};
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "example.com.", NULL, &hints,
                   AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
}

TEST_P(MockChannelTestAI, FamilyV4_MultipleAddresses) {
  DNSPacket rsp4;
  rsp4.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_A))
    .add_answer(new DNSARR("example.com", 100, {2, 3, 4, 5}))
    .add_answer(new DNSARR("example.com", 100, {7, 8, 9, 0}));
  ON_CALL(server_, OnRequest("example.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp4));
  AddrInfoResult result = {};
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "example.com.", NULL, &hints,
                   AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  std::stringstream ss;
  ss << result.ai_;
  EXPECT_EQ("{addr=[2.3.4.5], addr=[7.8.9.0]}", ss.str());
}

TEST_P(MockChannelTestAI, FamilyUnspecified) {
  DNSPacket rsp6;
  rsp6.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_AAAA))
    .add_answer(new DNSAaaaRR("example.com", 100,
                              {0x21, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                               0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x03}));
  ON_CALL(server_, OnRequest("example.com", T_AAAA))
    .WillByDefault(SetReply(&server_, &rsp6));
  DNSPacket rsp4;
  rsp4.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_A))
    .add_answer(new DNSARR("example.com", 100, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("example.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp4));
  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_UNSPEC;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "example.com.", NULL, &hints,
                   AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(2));
  EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
  EXPECT_THAT(result.ai_, IncludesV6Address("2121:0000:0000:0000:0000:0000:0000:0303"));
}

class MockEDNSChannelTestAI : public MockFlagsChannelOptsTestAI {
 public:
  MockEDNSChannelTestAI() : MockFlagsChannelOptsTestAI(ARES_FLAG_EDNS) {}
};

TEST_P(MockEDNSChannelTestAI, RetryWithoutEDNS) {
  DNSPacket rspfail;
  rspfail.set_response().set_aa().set_rcode(FORMERR)
    .add_question(new DNSQuestion("www.google.com", T_A));
  DNSPacket rspok;
  rspok.set_response()
    .add_question(new DNSQuestion("www.google.com", T_A))
    .add_answer(new DNSARR("www.google.com", 100, {1, 2, 3, 4}));
  EXPECT_CALL(server_, OnRequest("www.google.com", T_A))
    .WillOnce(SetReply(&server_, &rspfail))
    .WillOnce(SetReply(&server_, &rspok));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www.google.com.", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("1.2.3.4"));
}

TEST_P(MockChannelTestAI, SearchDomains) {
  DNSPacket nofirst;
  nofirst.set_response().set_aa().set_rcode(NXDOMAIN)
    .add_question(new DNSQuestion("www.first.com", T_A));
  ON_CALL(server_, OnRequest("www.first.com", T_A))
    .WillByDefault(SetReply(&server_, &nofirst));
  DNSPacket nosecond;
  nosecond.set_response().set_aa().set_rcode(NXDOMAIN)
    .add_question(new DNSQuestion("www.second.org", T_A));
  ON_CALL(server_, OnRequest("www.second.org", T_A))
    .WillByDefault(SetReply(&server_, &nosecond));
  DNSPacket yesthird;
  yesthird.set_response().set_aa()
    .add_question(new DNSQuestion("www.third.gov", T_A))
    .add_answer(new DNSARR("www.third.gov", 0x0200, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("www.third.gov", T_A))
    .WillByDefault(SetReply(&server_, &yesthird));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
}

TEST_P(MockChannelTestAI, SearchDomainsServFailOnAAAA) {
  DNSPacket nofirst;
  nofirst.set_response().set_aa().set_rcode(NXDOMAIN)
    .add_question(new DNSQuestion("www.first.com", T_AAAA));
  ON_CALL(server_, OnRequest("www.first.com", T_AAAA))
    .WillByDefault(SetReply(&server_, &nofirst));
  DNSPacket nofirst4;
  nofirst4.set_response().set_aa().set_rcode(NXDOMAIN)
    .add_question(new DNSQuestion("www.first.com", T_A));
  ON_CALL(server_, OnRequest("www.first.com", T_A))
    .WillByDefault(SetReply(&server_, &nofirst4));

  DNSPacket nosecond;
  nosecond.set_response().set_aa().set_rcode(NXDOMAIN)
    .add_question(new DNSQuestion("www.second.org", T_AAAA));
  ON_CALL(server_, OnRequest("www.second.org", T_AAAA))
    .WillByDefault(SetReply(&server_, &nosecond));
  DNSPacket yessecond4;
  yessecond4.set_response().set_aa()
    .add_question(new DNSQuestion("www.second.org", T_A))
    .add_answer(new DNSARR("www.second.org", 0x0200, {2, 3, 4, 5}));
  ON_CALL(server_, OnRequest("www.second.org", T_A))
    .WillByDefault(SetReply(&server_, &yessecond4));

  DNSPacket failthird;
  failthird.set_response().set_aa().set_rcode(SERVFAIL)
    .add_question(new DNSQuestion("www.third.gov", T_AAAA));
  ON_CALL(server_, OnRequest("www.third.gov", T_AAAA))
    .WillByDefault(SetReply(&server_, &failthird));
  DNSPacket failthird4;
  failthird4.set_response().set_aa().set_rcode(SERVFAIL)
    .add_question(new DNSQuestion("www.third.gov", T_A));
  ON_CALL(server_, OnRequest("www.third.gov", T_A))
    .WillByDefault(SetReply(&server_, &failthird4));

  AddrInfoResult result;
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_UNSPEC;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "www", NULL, &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
  EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
}

class MockMultiServerChannelTestAI
  : public MockChannelOptsTest,
    public ::testing::WithParamInterface< std::pair<int, bool> > {
 public:
  MockMultiServerChannelTestAI(ares_options *opts, int optmask)
    : MockChannelOptsTest(3, GetParam().first, GetParam().second, opts, optmask) {}
  void CheckExample() {
    AddrInfoResult result;
    struct ares_addrinfo_hints hints = {};
    hints.ai_family = AF_INET;
    hints.ai_flags = ARES_AI_NOSORT;
    ares_getaddrinfo(channel_, "www.example.com.", NULL, &hints, AddrInfoCallback, &result);
    Process();
    EXPECT_TRUE(result.done_);
    EXPECT_EQ(result.status_, ARES_SUCCESS);
    EXPECT_THAT(result.ai_, IncludesNumAddresses(1));
    EXPECT_THAT(result.ai_, IncludesV4Address("2.3.4.5"));
  }
};

class NoRotateMultiMockTestAI : public MockMultiServerChannelTestAI {
 public:
  NoRotateMultiMockTestAI() : MockMultiServerChannelTestAI(nullptr, ARES_OPT_NOROTATE) {}
};

class ServerFailoverOptsMockTestAI : public MockMultiServerChannelTestAI {
 public:
  ServerFailoverOptsMockTestAI()
    : MockMultiServerChannelTestAI(FillOptions(&opts_),
                                   ARES_OPT_SERVER_FAILOVER | ARES_OPT_NOROTATE) {}
  static struct ares_options* FillOptions(struct ares_options *opts) {
    memset(opts, 0, sizeof(struct ares_options));
    opts->server_failover_opts.retry_chance = 1;
    opts->server_failover_opts.retry_delay = 250;
    return opts;
  }
 private:
  struct ares_options opts_;
};

TEST_P(NoRotateMultiMockTestAI, ThirdServer) {
  struct ares_options opts;
  int optmask = 0;
  memset(&opts, 0, sizeof(opts));
  EXPECT_EQ(ARES_SUCCESS, ares_save_options(channel_, &opts, &optmask));
  EXPECT_EQ(ARES_OPT_NOROTATE, (optmask & ARES_OPT_NOROTATE));
  ares_destroy_options(&opts);

  DNSPacket servfailrsp;
  servfailrsp.set_response().set_aa().set_rcode(SERVFAIL)
    .add_question(new DNSQuestion("www.example.com", T_A));
  DNSPacket notimplrsp;
  notimplrsp.set_response().set_aa().set_rcode(NOTIMP)
    .add_question(new DNSQuestion("www.example.com", T_A));
  DNSPacket okrsp;
  okrsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.example.com", T_A))
    .add_answer(new DNSARR("www.example.com", 100, {2,3,4,5}));

   EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &servfailrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &notimplrsp));
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &okrsp));
  CheckExample();

  // Second time around, still starts from server [2], as [0] and [1] both
  // recorded failures
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &servfailrsp));
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &notimplrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &okrsp));
  CheckExample();

  // Third time around, server order is [1] (f0), [2] (f1), [0] (f2), which
  // means [1] will get called twice in a row as after the first call
  // order will be  [1] (f1), [2] (f1), [0] (f2) since sort order is
  // (failure count, index)
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &servfailrsp))
    .WillOnce(SetReply(servers_[1].get(), &notimplrsp));
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &notimplrsp));
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &okrsp));
  CheckExample();
}

// Test case to trigger server failover behavior. We use a retry chance of
// 100% and a retry delay of 250ms so that we can test behavior reliably.
TEST_P(ServerFailoverOptsMockTestAI, ServerFailoverOpts) {
  DNSPacket servfailrsp;
  servfailrsp.set_response().set_aa().set_rcode(SERVFAIL)
    .add_question(new DNSQuestion("www.example.com", T_A));
  DNSPacket okrsp;
  okrsp.set_response().set_aa()
    .add_question(new DNSQuestion("www.example.com", T_A))
    .add_answer(new DNSARR("www.example.com", 100, {2,3,4,5}));

  // 1. If all servers are healthy, then the first server should be selected.
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &okrsp));
  CheckExample();

  // 2. Failed servers should be retried after the retry delay.
  //
  // Fail server #0 but leave server #1 as healthy.
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &servfailrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &okrsp));
  CheckExample();

  // Sleep for the retry delay (actually a little more than 250ms to account
  // for unreliable timing, e.g. NTP slew) and send in another query. Server #0
  // should be retried.
  std::this_thread::sleep_for(std::chrono::milliseconds(260));
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &okrsp));
  CheckExample();

  // 3. If there are multiple failed servers, then the servers should be
  //    retried in sorted order.
  //
  // Fail all servers for the first round of tries. On the second round server
  // #1 responds successfully.
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &servfailrsp))
    .WillOnce(SetReply(servers_[0].get(), &servfailrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &servfailrsp))
    .WillOnce(SetReply(servers_[1].get(), &okrsp));
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &servfailrsp));
  CheckExample();

  // At this point the sorted servers look like [1] (f0) [2] (f1) [0] (f2).
  // Sleep for the retry delay and send in another query. Server #2 should be
  // retried first, and then server #0.
  std::this_thread::sleep_for(std::chrono::milliseconds(260));
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &servfailrsp));
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &okrsp));
  CheckExample();

  // 4. If there are multiple failed servers, then servers which have not yet
  //    met the retry delay should be skipped.
  //
  // The sorted servers currently look like [0] (f0) [1] (f0) [2] (f2) and
  // server #2 has just been retried.
  // Sleep for half the retry delay and trigger a failure on server #0.
  std::this_thread::sleep_for(std::chrono::milliseconds(130));
  EXPECT_CALL(*servers_[0], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[0].get(), &servfailrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &okrsp));
  CheckExample();

  // The sorted servers now look like [1] (f0) [0] (f1) [2] (f2). Server #0
  // has just failed whilst server #2 is halfway through the retry delay.
  // Sleep for another half the retry delay and check that server #2 is retried
  // whilst server #0 is not.
  std::this_thread::sleep_for(std::chrono::milliseconds(130));
  EXPECT_CALL(*servers_[2], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[2].get(), &servfailrsp));
  EXPECT_CALL(*servers_[1], OnRequest("www.example.com", T_A))
    .WillOnce(SetReply(servers_[1].get(), &okrsp));
  CheckExample();
}

TEST_P(MockChannelTestAI, FamilyV4ServiceName) {
  DNSPacket rsp4;
  rsp4.set_response().set_aa()
    .add_question(new DNSQuestion("example.com", T_A))
    .add_answer(new DNSARR("example.com", 100, {1, 1, 1, 1}))
    .add_answer(new DNSARR("example.com", 100, {2, 2, 2, 2}));
  ON_CALL(server_, OnRequest("example.com", T_A))
    .WillByDefault(SetReply(&server_, &rsp4));
  AddrInfoResult result = {};
  struct ares_addrinfo_hints hints = {};
  hints.ai_family = AF_INET;
  hints.ai_flags = ARES_AI_NOSORT;
  ares_getaddrinfo(channel_, "example.com", "http", &hints, AddrInfoCallback, &result);
  Process();
  EXPECT_TRUE(result.done_);
  std::stringstream ss;
  ss << result.ai_;
  EXPECT_EQ("{addr=[1.1.1.1:80], addr=[2.2.2.2:80]}", ss.str());
}

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockChannelTestAI,
                       ::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockUDPChannelTestAI,
                        ::testing::ValuesIn(ares::test::families), PrintFamily);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockTCPChannelTestAI,
                        ::testing::ValuesIn(ares::test::families), PrintFamily);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockExtraOptsTestAI,
			::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockExtraOptsNDots5TestAI,
      ::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockExtraOptsNDots0TestAI,
      ::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockNoCheckRespChannelTestAI,
			::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(AddressFamiliesAI, MockEDNSChannelTestAI,
			::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(TransportModesAI, NoRotateMultiMockTestAI,
			::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

INSTANTIATE_TEST_SUITE_P(TransportModesAI, ServerFailoverOptsMockTestAI,
			::testing::ValuesIn(ares::test::families_modes), PrintFamilyMode);

}  // namespace test
}  // namespace ares