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 "DnsTlsServer.h"
18 
19 #include <algorithm>
20 
21 #include <netdutils/InternetAddresses.h>
22 
23 namespace {
24 
25 // Returns a tuple of references to the elements of a.
26 auto make_tie(const sockaddr_in& a) {
27     return std::tie(a.sin_port, a.sin_addr.s_addr);
28 }
29 
30 // Returns a tuple of references to the elements of a.
31 auto make_tie(const sockaddr_in6& a) {
32     // Skip flowinfo, which is not relevant.
33     return std::tie(
34         a.sin6_port,
35         a.sin6_addr,
36         a.sin6_scope_id
37     );
38 }
39 
40 } // namespace
41 
42 // These binary operators make sockaddr_storage comparable.  They need to be
43 // in the global namespace so that the std::tuple < and == operators can see them.
44 static bool operator <(const in6_addr& x, const in6_addr& y) {
45     return std::lexicographical_compare(
46             std::begin(x.s6_addr), std::end(x.s6_addr),
47             std::begin(y.s6_addr), std::end(y.s6_addr));
48 }
49 
50 static bool operator ==(const in6_addr& x, const in6_addr& y) {
51     return std::equal(
52             std::begin(x.s6_addr), std::end(x.s6_addr),
53             std::begin(y.s6_addr), std::end(y.s6_addr));
54 }
55 
56 static bool operator <(const sockaddr_storage& x, const sockaddr_storage& y) {
57     if (x.ss_family != y.ss_family) {
58         return x.ss_family < y.ss_family;
59     }
60     // Same address family.
61     if (x.ss_family == AF_INET) {
62         const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x);
63         const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y);
64         return make_tie(x_sin) < make_tie(y_sin);
65     } else if (x.ss_family == AF_INET6) {
66         const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x);
67         const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y);
68         return make_tie(x_sin6) < make_tie(y_sin6);
69     }
70     return false;  // Unknown address type.  This is an error.
71 }
72 
73 static bool operator ==(const sockaddr_storage& x, const sockaddr_storage& y) {
74     if (x.ss_family != y.ss_family) {
75         return false;
76     }
77     // Same address family.
78     if (x.ss_family == AF_INET) {
79         const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x);
80         const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y);
81         return make_tie(x_sin) == make_tie(y_sin);
82     } else if (x.ss_family == AF_INET6) {
83         const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x);
84         const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y);
85         return make_tie(x_sin6) == make_tie(y_sin6);
86     }
87     return false;  // Unknown address type.  This is an error.
88 }
89 
90 namespace android {
91 namespace net {
92 
93 // This comparison ignores ports and certificates.
94 bool AddressComparator::operator() (const DnsTlsServer& x, const DnsTlsServer& y) const {
95     if (x.ss.ss_family != y.ss.ss_family) {
96         return x.ss.ss_family < y.ss.ss_family;
97     }
98     // Same address family.
99     if (x.ss.ss_family == AF_INET) {
100         const sockaddr_in& x_sin = reinterpret_cast<const sockaddr_in&>(x.ss);
101         const sockaddr_in& y_sin = reinterpret_cast<const sockaddr_in&>(y.ss);
102         return x_sin.sin_addr.s_addr < y_sin.sin_addr.s_addr;
103     } else if (x.ss.ss_family == AF_INET6) {
104         const sockaddr_in6& x_sin6 = reinterpret_cast<const sockaddr_in6&>(x.ss);
105         const sockaddr_in6& y_sin6 = reinterpret_cast<const sockaddr_in6&>(y.ss);
106         return std::tie(x_sin6.sin6_addr, x_sin6.sin6_scope_id) <
107                 std::tie(y_sin6.sin6_addr, y_sin6.sin6_scope_id);
108     }
109     return false;  // Unknown address type.  This is an error.
110 }
111 
112 // Returns a tuple of references to the elements of s.
113 auto make_tie(const DnsTlsServer& s) {
114     return std::tie(s.ss, s.name, s.protocol);
115 }
116 
117 bool DnsTlsServer::operator <(const DnsTlsServer& other) const {
118     return make_tie(*this) < make_tie(other);
119 }
120 
121 bool DnsTlsServer::operator ==(const DnsTlsServer& other) const {
122     return make_tie(*this) == make_tie(other);
123 }
124 
125 bool DnsTlsServer::wasExplicitlyConfigured() const {
126     return !name.empty();
127 }
128 
129 std::string DnsTlsServer::toIpString() const {
130     return netdutils::IPSockAddr::toIPSockAddr(ss).ip().toString();
131 }
132 
133 }  // namespace net
134 }  // namespace android
135