1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "dns/DnsTlsServer.h"
18
19 #include <algorithm>
20
21 namespace {
22
23 // Returns a tuple of references to the elements of a.
make_tie(const sockaddr_in & a)24 auto make_tie(const sockaddr_in& a) {
25 return std::tie(a.sin_port, a.sin_addr.s_addr);
26 }
27
28 // Returns a tuple of references to the elements of a.
make_tie(const sockaddr_in6 & a)29 auto make_tie(const sockaddr_in6& a) {
30 // Skip flowinfo, which is not relevant.
31 return std::tie(
32 a.sin6_port,
33 a.sin6_addr,
34 a.sin6_scope_id
35 );
36 }
37
38 } // namespace
39
40 // These binary operators make sockaddr_storage comparable. They need to be
41 // in the global namespace so that the std::tuple < and == operators can see them.
operator <(const in6_addr & x,const in6_addr & y)42 static bool operator <(const in6_addr& x, const in6_addr& y) {
43 return std::lexicographical_compare(
44 std::begin(x.s6_addr), std::end(x.s6_addr),
45 std::begin(y.s6_addr), std::end(y.s6_addr));
46 }
47
operator ==(const in6_addr & x,const in6_addr & y)48 static bool operator ==(const in6_addr& x, const in6_addr& y) {
49 return std::equal(
50 std::begin(x.s6_addr), std::end(x.s6_addr),
51 std::begin(y.s6_addr), std::end(y.s6_addr));
52 }
53
operator <(const sockaddr_storage & x,const sockaddr_storage & y)54 static bool operator <(const sockaddr_storage& x, const sockaddr_storage& y) {
55 if (x.ss_family != y.ss_family) {
56 return x.ss_family < y.ss_family;
57 }
58 // Same address family.
59 if (x.ss_family == AF_INET) {
60 const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x);
61 const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y);
62 return make_tie(x_sin) < make_tie(y_sin);
63 } else if (x.ss_family == AF_INET6) {
64 const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x);
65 const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y);
66 return make_tie(x_sin6) < make_tie(y_sin6);
67 }
68 return false; // Unknown address type. This is an error.
69 }
70
operator ==(const sockaddr_storage & x,const sockaddr_storage & y)71 static bool operator ==(const sockaddr_storage& x, const sockaddr_storage& y) {
72 if (x.ss_family != y.ss_family) {
73 return false;
74 }
75 // Same address family.
76 if (x.ss_family == AF_INET) {
77 const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x);
78 const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y);
79 return make_tie(x_sin) == make_tie(y_sin);
80 } else if (x.ss_family == AF_INET6) {
81 const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x);
82 const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y);
83 return make_tie(x_sin6) == make_tie(y_sin6);
84 }
85 return false; // Unknown address type. This is an error.
86 }
87
88 namespace android {
89 namespace net {
90
91 // This comparison ignores ports and fingerprints.
operator ()(const DnsTlsServer & x,const DnsTlsServer & y) const92 bool AddressComparator::operator() (const DnsTlsServer& x, const DnsTlsServer& y) const {
93 if (x.ss.ss_family != y.ss.ss_family) {
94 return x.ss.ss_family < y.ss.ss_family;
95 }
96 // Same address family.
97 if (x.ss.ss_family == AF_INET) {
98 const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x.ss);
99 const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y.ss);
100 return x_sin.sin_addr.s_addr < y_sin.sin_addr.s_addr;
101 } else if (x.ss.ss_family == AF_INET6) {
102 const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x.ss);
103 const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y.ss);
104 return std::tie(x_sin6.sin6_addr, x_sin6.sin6_scope_id) <
105 std::tie(y_sin6.sin6_addr, y_sin6.sin6_scope_id);
106 }
107 return false; // Unknown address type. This is an error.
108 }
109
110 // Returns a tuple of references to the elements of s.
make_tie(const DnsTlsServer & s)111 auto make_tie(const DnsTlsServer& s) {
112 return std::tie(
113 s.ss,
114 s.name,
115 s.fingerprints,
116 s.protocol
117 );
118 }
119
operator <(const DnsTlsServer & other) const120 bool DnsTlsServer::operator <(const DnsTlsServer& other) const {
121 return make_tie(*this) < make_tie(other);
122 }
123
operator ==(const DnsTlsServer & other) const124 bool DnsTlsServer::operator ==(const DnsTlsServer& other) const {
125 return make_tie(*this) == make_tie(other);
126 }
127
wasExplicitlyConfigured() const128 bool DnsTlsServer::wasExplicitlyConfigured() const {
129 return !name.empty() || !fingerprints.empty();
130 }
131
132 } // namespace net
133 } // namespace android
134