1 /*
2 * Copyright (C) 2018 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 "netdutils/InternetAddresses.h"
18
19 #include <string>
20
21 #include <android-base/stringprintf.h>
22 #include <arpa/inet.h>
23 #include <netdb.h>
24 #include <sys/socket.h>
25 #include <sys/types.h>
26
27 namespace android {
28
29 using base::StringPrintf;
30
31 namespace netdutils {
32
toString() const33 std::string IPAddress::toString() const noexcept {
34 char repr[INET6_ADDRSTRLEN] = "\0";
35
36 switch (mData.family) {
37 case AF_UNSPEC:
38 return "<unspecified>";
39 case AF_INET: {
40 const in_addr v4 = mData.ip.v4;
41 inet_ntop(AF_INET, &v4, repr, sizeof(repr));
42 break;
43 }
44 case AF_INET6: {
45 const in6_addr v6 = mData.ip.v6;
46 inet_ntop(AF_INET6, &v6, repr, sizeof(repr));
47 break;
48 }
49 default:
50 return "<unknown_family>";
51 }
52
53 if (mData.family == AF_INET6 && mData.scope_id > 0) {
54 return StringPrintf("%s%%%u", repr, mData.scope_id);
55 }
56
57 return repr;
58 }
59
forString(const std::string & repr,IPAddress * ip)60 bool IPAddress::forString(const std::string& repr, IPAddress* ip) {
61 const addrinfo hints = {
62 .ai_flags = AI_NUMERICHOST | AI_NUMERICSERV,
63 };
64 addrinfo* res;
65 const int ret = getaddrinfo(repr.c_str(), nullptr, &hints, &res);
66 ScopedAddrinfo res_cleanup(res);
67 if (ret != 0) {
68 return false;
69 }
70
71 bool rval = true;
72 switch (res[0].ai_family) {
73 case AF_INET: {
74 sockaddr_in* sin = (sockaddr_in*) res[0].ai_addr;
75 if (ip) *ip = IPAddress(sin->sin_addr);
76 break;
77 }
78 case AF_INET6: {
79 sockaddr_in6* sin6 = (sockaddr_in6*) res[0].ai_addr;
80 if (ip) *ip = IPAddress(sin6->sin6_addr, sin6->sin6_scope_id);
81 break;
82 }
83 default:
84 rval = false;
85 break;
86 }
87
88 return rval;
89 }
90
IPPrefix(const IPAddress & ip,int length)91 IPPrefix::IPPrefix(const IPAddress& ip, int length) : IPPrefix(ip) {
92 // Silently treat CIDR lengths like "-1" as meaning the full bit length
93 // appropriate to the address family.
94 if (length < 0) return;
95 if (length >= mData.cidrlen) return;
96
97 switch (mData.family) {
98 case AF_UNSPEC:
99 break;
100 case AF_INET: {
101 const in_addr_t mask = (length > 0) ? (~0U) << (IPV4_ADDR_BITS - length) : 0U;
102 mData.ip.v4.s_addr &= htonl(mask);
103 mData.cidrlen = static_cast<uint8_t>(length);
104 break;
105 }
106 case AF_INET6: {
107 // The byte in which this CIDR length falls.
108 const int which = length / 8;
109 const int mask = (length % 8 == 0) ? 0 : 0xff << (8 - length % 8);
110 mData.ip.v6.s6_addr[which] &= mask;
111 for (int i = which + 1; i < IPV6_ADDR_LEN; i++) {
112 mData.ip.v6.s6_addr[i] = 0U;
113 }
114 mData.cidrlen = static_cast<uint8_t>(length);
115 break;
116 }
117 default:
118 // TODO: Complain bitterly about possible data corruption?
119 return;
120 }
121 }
122
isUninitialized() const123 bool IPPrefix::isUninitialized() const noexcept {
124 static const internal_::compact_ipdata empty{};
125 return mData == empty;
126 }
127
forString(const std::string & repr,IPPrefix * prefix)128 bool IPPrefix::forString(const std::string& repr, IPPrefix* prefix) {
129 size_t index = repr.find('/');
130 if (index == std::string::npos) return false;
131
132 // Parse the IP address.
133 IPAddress ip;
134 if (!IPAddress::forString(repr.substr(0, index), &ip)) return false;
135
136 // Parse the prefix length. Can't use base::ParseUint because it accepts non-base 10 input.
137 const char* prefixString = repr.c_str() + index + 1;
138 if (!isdigit(*prefixString)) return false;
139 char* endptr;
140 unsigned long prefixlen = strtoul(prefixString, &endptr, 10);
141 if (*endptr != '\0') return false;
142
143 uint8_t maxlen = (ip.family() == AF_INET) ? 32 : 128;
144 if (prefixlen > maxlen) return false;
145
146 *prefix = IPPrefix(ip, prefixlen);
147 return true;
148 }
149
toString() const150 std::string IPPrefix::toString() const noexcept {
151 return StringPrintf("%s/%d", ip().toString().c_str(), mData.cidrlen);
152 }
153
toString() const154 std::string IPSockAddr::toString() const noexcept {
155 switch (mData.family) {
156 case AF_INET6:
157 return StringPrintf("[%s]:%u", ip().toString().c_str(), mData.port);
158 default:
159 return StringPrintf("%s:%u", ip().toString().c_str(), mData.port);
160 }
161 }
162
163 } // namespace netdutils
164 } // namespace android
165