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 #pragma once
18
19 #include <netdb.h>
20 #include <netinet/in.h>
21 #include <stdint.h>
22 #include <cstring>
23 #include <limits>
24 #include <string>
25
26 #include "netdutils/NetworkConstants.h"
27
28 namespace android {
29 namespace netdutils {
30
31 namespace internal_ {
32
33 // A structure to hold data for dealing with Internet addresses (IPAddress) and
34 // related types such as IPSockAddr and IPPrefix.
35 struct compact_ipdata {
36 uint8_t family{AF_UNSPEC};
37 uint8_t cidrlen{0U}; // written and read in host-byte order
38 in_port_t port{0U}; // written and read in host-byte order
39 uint32_t scope_id{0U};
40 union {
41 in_addr v4;
42 in6_addr v6;
43 } ip{.v6 = IN6ADDR_ANY_INIT}; // written and read in network-byte order
44
45 // Classes that use compact_ipdata and this method should be sure to clear
46 // (i.e. zero or make uniform) any fields not relevant to the class.
47 friend bool operator==(const compact_ipdata& a, const compact_ipdata& b) {
48 if ((a.family != b.family) || (a.cidrlen != b.cidrlen) || (a.port != b.port) ||
49 (a.scope_id != b.scope_id)) {
50 return false;
51 }
52 switch (a.family) {
53 case AF_UNSPEC:
54 // After the above checks, two AF_UNSPEC objects can be
55 // considered equal, for convenience.
56 return true;
57 case AF_INET: {
58 const in_addr v4a = a.ip.v4;
59 const in_addr v4b = b.ip.v4;
60 return (v4a.s_addr == v4b.s_addr);
61 }
62 case AF_INET6: {
63 const in6_addr v6a = a.ip.v6;
64 const in6_addr v6b = b.ip.v6;
65 return IN6_ARE_ADDR_EQUAL(&v6a, &v6b);
66 }
67 }
68 return false;
69 }
70
71 // Classes that use compact_ipdata and this method should be sure to clear
72 // (i.e. zero or make uniform) any fields not relevant to the class.
73 friend bool operator!=(const compact_ipdata& a, const compact_ipdata& b) { return !(a == b); }
74
75 // Classes that use compact_ipdata and this method should be sure to clear
76 // (i.e. zero or make uniform) any fields not relevant to the class.
77 friend bool operator<(const compact_ipdata& a, const compact_ipdata& b) {
78 if (a.family != b.family) return (a.family < b.family);
79 switch (a.family) {
80 case AF_INET: {
81 const in_addr v4a = a.ip.v4;
82 const in_addr v4b = b.ip.v4;
83 if (v4a.s_addr != v4b.s_addr) return (ntohl(v4a.s_addr) < ntohl(v4b.s_addr));
84 break;
85 }
86 case AF_INET6: {
87 const in6_addr v6a = a.ip.v6;
88 const in6_addr v6b = b.ip.v6;
89 const int cmp = std::memcmp(v6a.s6_addr, v6b.s6_addr, IPV6_ADDR_LEN);
90 if (cmp != 0) return cmp < 0;
91 break;
92 }
93 }
94 if (a.cidrlen != b.cidrlen) return (a.cidrlen < b.cidrlen);
95 if (a.port != b.port) return (a.port < b.port);
96 return (a.scope_id < b.scope_id);
97 }
98 };
99
100 static_assert(AF_UNSPEC <= std::numeric_limits<uint8_t>::max(), "AF_UNSPEC value too large");
101 static_assert(AF_INET <= std::numeric_limits<uint8_t>::max(), "AF_INET value too large");
102 static_assert(AF_INET6 <= std::numeric_limits<uint8_t>::max(), "AF_INET6 value too large");
103 static_assert(sizeof(compact_ipdata) == 24U, "compact_ipdata unexpectedly large");
104
105 } // namespace internal_
106
107 struct AddrinfoDeleter {
operatorAddrinfoDeleter108 void operator()(struct addrinfo* p) const {
109 if (p != nullptr) {
110 freeaddrinfo(p);
111 }
112 }
113 };
114
115 typedef std::unique_ptr<struct addrinfo, struct AddrinfoDeleter> ScopedAddrinfo;
116
usesScopedIds(const in6_addr & ipv6)117 inline bool usesScopedIds(const in6_addr& ipv6) {
118 return (IN6_IS_ADDR_LINKLOCAL(&ipv6) || IN6_IS_ADDR_MC_LINKLOCAL(&ipv6));
119 }
120
121 class IPPrefix;
122 class IPSockAddr;
123
124 class IPAddress {
125 public:
126 static bool forString(const std::string& repr, IPAddress* ip);
forString(const std::string & repr)127 static IPAddress forString(const std::string& repr) {
128 IPAddress ip;
129 if (!forString(repr, &ip)) return IPAddress();
130 return ip;
131 }
132
133 IPAddress() = default;
134 IPAddress(const IPAddress&) = default;
135 IPAddress(IPAddress&&) = default;
136
IPAddress(const in_addr & ipv4)137 explicit IPAddress(const in_addr& ipv4)
138 : mData({AF_INET, IPV4_ADDR_BITS, 0U, 0U, {.v4 = ipv4}}) {}
IPAddress(const in6_addr & ipv6)139 explicit IPAddress(const in6_addr& ipv6)
140 : mData({AF_INET6, IPV6_ADDR_BITS, 0U, 0U, {.v6 = ipv6}}) {}
IPAddress(const in6_addr & ipv6,uint32_t scope_id)141 IPAddress(const in6_addr& ipv6, uint32_t scope_id)
142 : mData({AF_INET6,
143 IPV6_ADDR_BITS,
144 0U,
145 // Sanity check: scoped_ids only for link-local addresses.
146 usesScopedIds(ipv6) ? scope_id : 0U,
147 {.v6 = ipv6}}) {}
IPAddress(const IPAddress & ip,uint32_t scope_id)148 IPAddress(const IPAddress& ip, uint32_t scope_id) : IPAddress(ip) {
149 mData.scope_id = (family() == AF_INET6 && usesScopedIds(mData.ip.v6)) ? scope_id : 0U;
150 }
151
152 IPAddress& operator=(const IPAddress&) = default;
153 IPAddress& operator=(IPAddress&&) = default;
154
family()155 constexpr sa_family_t family() const noexcept { return mData.family; }
scope_id()156 constexpr uint32_t scope_id() const noexcept { return mData.scope_id; }
157
158 std::string toString() const noexcept;
159
160 friend std::ostream& operator<<(std::ostream& os, const IPAddress& ip) {
161 os << ip.toString();
162 return os;
163 }
164 friend bool operator==(const IPAddress& a, const IPAddress& b) { return (a.mData == b.mData); }
165 friend bool operator!=(const IPAddress& a, const IPAddress& b) { return (a.mData != b.mData); }
166 friend bool operator<(const IPAddress& a, const IPAddress& b) { return (a.mData < b.mData); }
167 friend bool operator>(const IPAddress& a, const IPAddress& b) { return (b.mData < a.mData); }
168 friend bool operator<=(const IPAddress& a, const IPAddress& b) { return (a < b) || (a == b); }
169 friend bool operator>=(const IPAddress& a, const IPAddress& b) { return (b < a) || (a == b); }
170
171 private:
172 friend class IPPrefix;
173 friend class IPSockAddr;
174
IPAddress(const internal_::compact_ipdata & ipdata)175 explicit IPAddress(const internal_::compact_ipdata& ipdata) : mData(ipdata) {
176 mData.port = 0U;
177 switch (mData.family) {
178 case AF_INET:
179 mData.cidrlen = IPV4_ADDR_BITS;
180 mData.scope_id = 0U;
181 break;
182 case AF_INET6:
183 mData.cidrlen = IPV6_ADDR_BITS;
184 if (usesScopedIds(ipdata.ip.v6)) mData.scope_id = ipdata.scope_id;
185 break;
186 default:
187 mData.cidrlen = 0U;
188 mData.scope_id = 0U;
189 break;
190 }
191 }
192
193 internal_::compact_ipdata mData{};
194 };
195
196 class IPPrefix {
197 public:
198 static bool forString(const std::string& repr, IPPrefix* prefix);
forString(const std::string & repr)199 static IPPrefix forString(const std::string& repr) {
200 IPPrefix prefix;
201 if (!forString(repr, &prefix)) return IPPrefix();
202 return prefix;
203 }
204
205 IPPrefix() = default;
206 IPPrefix(const IPPrefix&) = default;
207 IPPrefix(IPPrefix&&) = default;
208
IPPrefix(const IPAddress & ip)209 explicit IPPrefix(const IPAddress& ip) : mData(ip.mData) {}
210
211 // Truncate the IP address |ip| at length |length|. Lengths greater than
212 // the address-family-relevant maximum, along with negative values, are
213 // interpreted as if the address-family-relevant maximum had been given.
214 IPPrefix(const IPAddress& ip, int length);
215
216 IPPrefix& operator=(const IPPrefix&) = default;
217 IPPrefix& operator=(IPPrefix&&) = default;
218
family()219 constexpr sa_family_t family() const noexcept { return mData.family; }
ip()220 IPAddress ip() const noexcept { return IPAddress(mData); }
addr4()221 in_addr addr4() const noexcept { return mData.ip.v4; }
addr6()222 in6_addr addr6() const noexcept { return mData.ip.v6; }
length()223 constexpr int length() const noexcept { return mData.cidrlen; }
224
225 bool isUninitialized() const noexcept;
226 std::string toString() const noexcept;
227
228 friend std::ostream& operator<<(std::ostream& os, const IPPrefix& prefix) {
229 os << prefix.toString();
230 return os;
231 }
232 friend bool operator==(const IPPrefix& a, const IPPrefix& b) { return (a.mData == b.mData); }
233 friend bool operator!=(const IPPrefix& a, const IPPrefix& b) { return (a.mData != b.mData); }
234 friend bool operator<(const IPPrefix& a, const IPPrefix& b) { return (a.mData < b.mData); }
235 friend bool operator>(const IPPrefix& a, const IPPrefix& b) { return (b.mData < a.mData); }
236 friend bool operator<=(const IPPrefix& a, const IPPrefix& b) { return (a < b) || (a == b); }
237 friend bool operator>=(const IPPrefix& a, const IPPrefix& b) { return (b < a) || (a == b); }
238
239 private:
240 internal_::compact_ipdata mData{};
241 };
242
243 // An Internet socket address.
244 //
245 // Cannot represent other types of socket addresses (e.g. UNIX socket address, et cetera).
246 class IPSockAddr {
247 public:
248 // TODO: static forString
249
toIPSockAddr(const std::string & repr,in_port_t port)250 static IPSockAddr toIPSockAddr(const std::string& repr, in_port_t port) {
251 return IPSockAddr(IPAddress::forString(repr), port);
252 }
toIPSockAddr(const sockaddr & sa)253 static IPSockAddr toIPSockAddr(const sockaddr& sa) {
254 switch (sa.sa_family) {
255 case AF_INET:
256 return IPSockAddr(*reinterpret_cast<const sockaddr_in*>(&sa));
257 case AF_INET6:
258 return IPSockAddr(*reinterpret_cast<const sockaddr_in6*>(&sa));
259 default:
260 return IPSockAddr();
261 }
262 }
toIPSockAddr(const sockaddr_storage & ss)263 static IPSockAddr toIPSockAddr(const sockaddr_storage& ss) {
264 return toIPSockAddr(*reinterpret_cast<const sockaddr*>(&ss));
265 }
266
267 IPSockAddr() = default;
268 IPSockAddr(const IPSockAddr&) = default;
269 IPSockAddr(IPSockAddr&&) = default;
270
IPSockAddr(const IPAddress & ip)271 explicit IPSockAddr(const IPAddress& ip) : mData(ip.mData) {}
IPSockAddr(const IPAddress & ip,in_port_t port)272 IPSockAddr(const IPAddress& ip, in_port_t port) : mData(ip.mData) { mData.port = port; }
IPSockAddr(const sockaddr_in & ipv4sa)273 explicit IPSockAddr(const sockaddr_in& ipv4sa)
274 : IPSockAddr(IPAddress(ipv4sa.sin_addr), ntohs(ipv4sa.sin_port)) {}
IPSockAddr(const sockaddr_in6 & ipv6sa)275 explicit IPSockAddr(const sockaddr_in6& ipv6sa)
276 : IPSockAddr(IPAddress(ipv6sa.sin6_addr, ipv6sa.sin6_scope_id), ntohs(ipv6sa.sin6_port)) {}
277
278 IPSockAddr& operator=(const IPSockAddr&) = default;
279 IPSockAddr& operator=(IPSockAddr&&) = default;
280
family()281 constexpr sa_family_t family() const noexcept { return mData.family; }
ip()282 IPAddress ip() const noexcept { return IPAddress(mData); }
port()283 constexpr in_port_t port() const noexcept { return mData.port; }
284
285 // Implicit conversion to sockaddr_storage.
sockaddr_storage()286 operator sockaddr_storage() const noexcept {
287 sockaddr_storage ss;
288 ss.ss_family = mData.family;
289 switch (mData.family) {
290 case AF_INET:
291 reinterpret_cast<sockaddr_in*>(&ss)->sin_addr = mData.ip.v4;
292 reinterpret_cast<sockaddr_in*>(&ss)->sin_port = htons(mData.port);
293 break;
294 case AF_INET6:
295 reinterpret_cast<sockaddr_in6*>(&ss)->sin6_addr = mData.ip.v6;
296 reinterpret_cast<sockaddr_in6*>(&ss)->sin6_port = htons(mData.port);
297 reinterpret_cast<sockaddr_in6*>(&ss)->sin6_scope_id = mData.scope_id;
298 break;
299 }
300 return ss;
301 }
302
303 std::string toString() const noexcept;
304
305 friend std::ostream& operator<<(std::ostream& os, const IPSockAddr& prefix) {
306 os << prefix.toString();
307 return os;
308 }
309 friend bool operator==(const IPSockAddr& a, const IPSockAddr& b) {
310 return (a.mData == b.mData);
311 }
312 friend bool operator!=(const IPSockAddr& a, const IPSockAddr& b) {
313 return (a.mData != b.mData);
314 }
315 friend bool operator<(const IPSockAddr& a, const IPSockAddr& b) { return (a.mData < b.mData); }
316 friend bool operator>(const IPSockAddr& a, const IPSockAddr& b) { return (b.mData < a.mData); }
317 friend bool operator<=(const IPSockAddr& a, const IPSockAddr& b) { return (a < b) || (a == b); }
318 friend bool operator>=(const IPSockAddr& a, const IPSockAddr& b) { return (b < a) || (a == b); }
319
320 private:
321 internal_::compact_ipdata mData{};
322 };
323
324 } // namespace netdutils
325 } // namespace android
326