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
21namespace {
22
23// Returns a tuple of references to the elements of a.
24auto 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.
29auto 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.
42static 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
48static 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
54static 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
71static 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
88namespace android {
89namespace net {
90
91// This comparison ignores ports and fingerprints.
92bool 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.
111auto make_tie(const DnsTlsServer& s) {
112    return std::tie(
113        s.ss,
114        s.name,
115        s.fingerprints,
116        s.protocol
117    );
118}
119
120bool DnsTlsServer::operator <(const DnsTlsServer& other) const {
121    return make_tie(*this) < make_tie(other);
122}
123
124bool DnsTlsServer::operator ==(const DnsTlsServer& other) const {
125    return make_tie(*this) == make_tie(other);
126}
127
128bool DnsTlsServer::wasExplicitlyConfigured() const {
129    return !name.empty() || !fingerprints.empty();
130}
131
132}  // namespace net
133}  // namespace android
134