1 // Copyright 2019 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/dns/public/resolv_reader.h"
6
7 #include <arpa/inet.h>
8 #include <resolv.h>
9
10 #include <memory>
11 #include <optional>
12 #include <utility>
13 #include <vector>
14
15 #include "base/cancelable_callback.h"
16 #include "base/check.h"
17 #include "base/functional/bind.h"
18 #include "base/run_loop.h"
19 #include "base/sys_byteorder.h"
20 #include "base/task/sequenced_task_runner.h"
21 #include "base/task/task_traits.h"
22 #include "base/task/thread_pool.h"
23 #include "build/build_config.h"
24 #include "net/base/ip_address.h"
25 #include "net/dns/public/dns_protocol.h"
26 #include "testing/gtest/include/gtest/gtest.h"
27
28 namespace net {
29
30 namespace {
31
32 // MAXNS is normally 3, but let's test 4 if possible.
33 const char* const kNameserversIPv4[] = {
34 "8.8.8.8",
35 "192.168.1.1",
36 "63.1.2.4",
37 "1.0.0.1",
38 };
39
40 #if BUILDFLAG(IS_LINUX)
41 const char* const kNameserversIPv6[] = {
42 nullptr,
43 "2001:db8::42",
44 nullptr,
45 "::FFFF:129.144.52.38",
46 };
47 #endif
48
49 // Fills in |res| with sane configuration.
InitializeResState(res_state res)50 void InitializeResState(res_state res) {
51 memset(res, 0, sizeof(*res));
52 res->options = RES_INIT;
53
54 for (unsigned i = 0; i < std::size(kNameserversIPv4) && i < MAXNS; ++i) {
55 struct sockaddr_in sa;
56 sa.sin_family = AF_INET;
57 sa.sin_port = base::HostToNet16(NS_DEFAULTPORT + i);
58 inet_pton(AF_INET, kNameserversIPv4[i], &sa.sin_addr);
59 res->nsaddr_list[i] = sa;
60 ++res->nscount;
61 }
62
63 #if BUILDFLAG(IS_LINUX)
64 // Install IPv6 addresses, replacing the corresponding IPv4 addresses.
65 unsigned nscount6 = 0;
66 for (unsigned i = 0; i < std::size(kNameserversIPv6) && i < MAXNS; ++i) {
67 if (!kNameserversIPv6[i])
68 continue;
69 // Must use malloc to mimic res_ninit. Expect to be freed in
70 // `TestResolvReader::CloseResState()`.
71 struct sockaddr_in6* sa6;
72 sa6 = static_cast<sockaddr_in6*>(malloc(sizeof(*sa6)));
73 sa6->sin6_family = AF_INET6;
74 sa6->sin6_port = base::HostToNet16(NS_DEFAULTPORT - i);
75 inet_pton(AF_INET6, kNameserversIPv6[i], &sa6->sin6_addr);
76 res->_u._ext.nsaddrs[i] = sa6;
77 memset(&res->nsaddr_list[i], 0, sizeof res->nsaddr_list[i]);
78 ++nscount6;
79 }
80 res->_u._ext.nscount6 = nscount6;
81 #endif
82 }
83
FreeResState(struct __res_state * res)84 void FreeResState(struct __res_state* res) {
85 #if BUILDFLAG(IS_LINUX)
86 for (int i = 0; i < res->nscount; ++i) {
87 if (res->_u._ext.nsaddrs[i] != nullptr)
88 free(res->_u._ext.nsaddrs[i]);
89 }
90 #endif
91 }
92
TEST(ResolvReaderTest,GetNameservers)93 TEST(ResolvReaderTest, GetNameservers) {
94 auto res = std::make_unique<struct __res_state>();
95 InitializeResState(res.get());
96
97 std::optional<std::vector<IPEndPoint>> nameservers =
98 GetNameservers(*res.get());
99 EXPECT_TRUE(nameservers.has_value());
100
101 #if BUILDFLAG(IS_LINUX)
102 EXPECT_EQ(kNameserversIPv4[0], nameservers->at(0).ToStringWithoutPort());
103 EXPECT_EQ(kNameserversIPv6[1], nameservers->at(1).ToStringWithoutPort());
104 EXPECT_EQ(kNameserversIPv4[2], nameservers->at(2).ToStringWithoutPort());
105 #else
106 EXPECT_EQ(kNameserversIPv4[0], nameservers->at(0).ToStringWithoutPort());
107 EXPECT_EQ(kNameserversIPv4[1], nameservers->at(1).ToStringWithoutPort());
108 EXPECT_EQ(kNameserversIPv4[2], nameservers->at(2).ToStringWithoutPort());
109 #endif
110
111 FreeResState(res.get());
112 }
113
114 } // namespace
115
116 } // namespace net
117