1 /*
2 * This file is part of OpenTTD.
3 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
4 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6 */
7
8 /** @file core/address.cpp Implementation of the address. */
9
10 #include "../../stdafx.h"
11
12 #include "address.h"
13 #include "../network_internal.h"
14 #include "../../debug.h"
15
16 #include "../../safeguards.h"
17
18 /**
19 * Get the hostname; in case it wasn't given the
20 * IPv4 dotted representation is given.
21 * @return the hostname
22 */
GetHostname()23 const std::string &NetworkAddress::GetHostname()
24 {
25 if (this->hostname.empty() && this->address.ss_family != AF_UNSPEC) {
26 assert(this->address_length != 0);
27 char buffer[NETWORK_HOSTNAME_LENGTH];
28 getnameinfo((struct sockaddr *)&this->address, this->address_length, buffer, sizeof(buffer), nullptr, 0, NI_NUMERICHOST);
29 this->hostname = buffer;
30 }
31 return this->hostname;
32 }
33
34 /**
35 * Get the port.
36 * @return the port.
37 */
GetPort() const38 uint16 NetworkAddress::GetPort() const
39 {
40 switch (this->address.ss_family) {
41 case AF_UNSPEC:
42 case AF_INET:
43 return ntohs(((const struct sockaddr_in *)&this->address)->sin_port);
44
45 case AF_INET6:
46 return ntohs(((const struct sockaddr_in6 *)&this->address)->sin6_port);
47
48 default:
49 NOT_REACHED();
50 }
51 }
52
53 /**
54 * Set the port.
55 * @param port set the port number.
56 */
SetPort(uint16 port)57 void NetworkAddress::SetPort(uint16 port)
58 {
59 switch (this->address.ss_family) {
60 case AF_UNSPEC:
61 case AF_INET:
62 ((struct sockaddr_in*)&this->address)->sin_port = htons(port);
63 break;
64
65 case AF_INET6:
66 ((struct sockaddr_in6*)&this->address)->sin6_port = htons(port);
67 break;
68
69 default:
70 NOT_REACHED();
71 }
72 }
73
74 /**
75 * Helper to get the formatting string of an address for a given family.
76 * @param family The family to get the address format for.
77 * @param with_family Whether to add the familty to the address (e.g. IPv4).
78 * @return The format string for the address.
79 */
GetAddressFormatString(uint16 family,bool with_family)80 static const char *GetAddressFormatString(uint16 family, bool with_family)
81 {
82 switch (family) {
83 case AF_INET: return with_family ? "{}:{} (IPv4)" : "{}:{}";
84 case AF_INET6: return with_family ? "[{}]:{} (IPv6)" : "[{}]:{}";
85 default: return with_family ? "{}:{} (IPv?)" : "{}:{}";
86 }
87 }
88
89 /**
90 * Get the address as a string, e.g. 127.0.0.1:12345.
91 * @param with_family whether to add the family (e.g. IPvX).
92 * @return the address
93 */
GetAddressAsString(bool with_family)94 std::string NetworkAddress::GetAddressAsString(bool with_family)
95 {
96 return fmt::format(GetAddressFormatString(this->GetAddress()->ss_family, with_family), this->GetHostname(), this->GetPort());
97 }
98
99 /**
100 * Helper function to resolve without opening a socket.
101 * @param runp information about the socket to try not
102 * @return the opened socket or INVALID_SOCKET
103 */
ResolveLoopProc(addrinfo * runp)104 static SOCKET ResolveLoopProc(addrinfo *runp)
105 {
106 /* We just want the first 'entry', so return a valid socket. */
107 return !INVALID_SOCKET;
108 }
109
110 /**
111 * Get the address in its internal representation.
112 * @return the address
113 */
GetAddress()114 const sockaddr_storage *NetworkAddress::GetAddress()
115 {
116 if (!this->IsResolved()) {
117 /* Here we try to resolve a network address. We use SOCK_STREAM as
118 * socket type because some stupid OSes, like Solaris, cannot be
119 * bothered to implement the specifications and allow '0' as value
120 * that means "don't care whether it is SOCK_STREAM or SOCK_DGRAM".
121 */
122 this->Resolve(this->address.ss_family, SOCK_STREAM, AI_ADDRCONFIG, nullptr, ResolveLoopProc);
123 this->resolved = true;
124 }
125 return &this->address;
126 }
127
128 /**
129 * Checks of this address is of the given family.
130 * @param family the family to check against
131 * @return true if it is of the given family
132 */
IsFamily(int family)133 bool NetworkAddress::IsFamily(int family)
134 {
135 if (!this->IsResolved()) {
136 this->Resolve(family, SOCK_STREAM, AI_ADDRCONFIG, nullptr, ResolveLoopProc);
137 }
138 return this->address.ss_family == family;
139 }
140
141 /**
142 * Checks whether this IP address is contained by the given netmask.
143 * @param netmask the netmask in CIDR notation to test against.
144 * @note netmask without /n assumes all bits need to match.
145 * @return true if this IP is within the netmask.
146 */
IsInNetmask(const std::string & netmask)147 bool NetworkAddress::IsInNetmask(const std::string &netmask)
148 {
149 /* Resolve it if we didn't do it already */
150 if (!this->IsResolved()) this->GetAddress();
151
152 int cidr = this->address.ss_family == AF_INET ? 32 : 128;
153
154 NetworkAddress mask_address;
155
156 /* Check for CIDR separator */
157 auto cidr_separator_location = netmask.find('/');
158 if (cidr_separator_location != std::string::npos) {
159 int tmp_cidr = atoi(netmask.substr(cidr_separator_location + 1).c_str());
160
161 /* Invalid CIDR, treat as single host */
162 if (tmp_cidr > 0 && tmp_cidr < cidr) cidr = tmp_cidr;
163
164 /* Remove the / so that NetworkAddress works on the IP portion */
165 mask_address = NetworkAddress(netmask.substr(0, cidr_separator_location), 0, this->address.ss_family);
166 } else {
167 mask_address = NetworkAddress(netmask, 0, this->address.ss_family);
168 }
169
170 if (mask_address.GetAddressLength() == 0) return false;
171
172 uint32 *ip;
173 uint32 *mask;
174 switch (this->address.ss_family) {
175 case AF_INET:
176 ip = (uint32*)&((struct sockaddr_in*)&this->address)->sin_addr.s_addr;
177 mask = (uint32*)&((struct sockaddr_in*)&mask_address.address)->sin_addr.s_addr;
178 break;
179
180 case AF_INET6:
181 ip = (uint32*)&((struct sockaddr_in6*)&this->address)->sin6_addr;
182 mask = (uint32*)&((struct sockaddr_in6*)&mask_address.address)->sin6_addr;
183 break;
184
185 default:
186 NOT_REACHED();
187 }
188
189 while (cidr > 0) {
190 uint32 msk = cidr >= 32 ? (uint32)-1 : htonl(-(1 << (32 - cidr)));
191 if ((*mask++ & msk) != (*ip++ & msk)) return false;
192
193 cidr -= 32;
194 }
195
196 return true;
197 }
198
199 /**
200 * Resolve this address into a socket
201 * @param family the type of 'protocol' (IPv4, IPv6)
202 * @param socktype the type of socket (TCP, UDP, etc)
203 * @param flags the flags to send to getaddrinfo
204 * @param sockets the list of sockets to add the sockets to
205 * @param func the inner working while looping over the address info
206 * @return the resolved socket or INVALID_SOCKET.
207 */
Resolve(int family,int socktype,int flags,SocketList * sockets,LoopProc func)208 SOCKET NetworkAddress::Resolve(int family, int socktype, int flags, SocketList *sockets, LoopProc func)
209 {
210 struct addrinfo *ai;
211 struct addrinfo hints;
212 memset(&hints, 0, sizeof (hints));
213 hints.ai_family = family;
214 hints.ai_flags = flags;
215 hints.ai_socktype = socktype;
216
217 /* The port needs to be a string. Six is enough to contain all characters + '\0'. */
218 char port_name[6];
219 seprintf(port_name, lastof(port_name), "%u", this->GetPort());
220
221 bool reset_hostname = false;
222 /* Setting both hostname to nullptr and port to 0 is not allowed.
223 * As port 0 means bind to any port, the other must mean that
224 * we want to bind to 'all' IPs. */
225 if (this->hostname.empty() && this->address_length == 0 && this->GetPort() == 0) {
226 reset_hostname = true;
227 int fam = this->address.ss_family;
228 if (fam == AF_UNSPEC) fam = family;
229 this->hostname = fam == AF_INET ? "0.0.0.0" : "::";
230 }
231
232 static bool _resolve_timeout_error_message_shown = false;
233 auto start = std::chrono::steady_clock::now();
234 int e = getaddrinfo(this->hostname.empty() ? nullptr : this->hostname.c_str(), port_name, &hints, &ai);
235 auto end = std::chrono::steady_clock::now();
236 std::chrono::seconds duration = std::chrono::duration_cast<std::chrono::seconds>(end - start);
237 if (!_resolve_timeout_error_message_shown && duration >= std::chrono::seconds(5)) {
238 Debug(net, 0, "getaddrinfo for hostname \"{}\", port {}, address family {} and socket type {} took {} seconds",
239 this->hostname, port_name, AddressFamilyAsString(family), SocketTypeAsString(socktype), duration.count());
240 Debug(net, 0, " this is likely an issue in the DNS name resolver's configuration causing it to time out");
241 _resolve_timeout_error_message_shown = true;
242 }
243
244
245 if (reset_hostname) this->hostname.clear();
246
247 if (e != 0) {
248 if (func != ResolveLoopProc) {
249 Debug(net, 0, "getaddrinfo for hostname \"{}\", port {}, address family {} and socket type {} failed: {}",
250 this->hostname, port_name, AddressFamilyAsString(family), SocketTypeAsString(socktype), FS2OTTD(gai_strerror(e)));
251 }
252 return INVALID_SOCKET;
253 }
254
255 SOCKET sock = INVALID_SOCKET;
256 for (struct addrinfo *runp = ai; runp != nullptr; runp = runp->ai_next) {
257 /* When we are binding to multiple sockets, make sure we do not
258 * connect to one with exactly the same address twice. That's
259 * of course totally unneeded ;) */
260 if (sockets != nullptr) {
261 NetworkAddress address(runp->ai_addr, (int)runp->ai_addrlen);
262 if (sockets->Contains(address)) continue;
263 }
264 sock = func(runp);
265 if (sock == INVALID_SOCKET) continue;
266
267 if (sockets == nullptr) {
268 this->address_length = (int)runp->ai_addrlen;
269 assert(sizeof(this->address) >= runp->ai_addrlen);
270 memcpy(&this->address, runp->ai_addr, runp->ai_addrlen);
271 #ifdef __EMSCRIPTEN__
272 /* Emscripten doesn't zero sin_zero, but as we compare addresses
273 * to see if they are the same address, we need them to be zero'd.
274 * Emscripten is, as far as we know, the only OS not doing this.
275 *
276 * https://github.com/emscripten-core/emscripten/issues/12998
277 */
278 if (this->address.ss_family == AF_INET) {
279 sockaddr_in *address_ipv4 = (sockaddr_in *)&this->address;
280 memset(address_ipv4->sin_zero, 0, sizeof(address_ipv4->sin_zero));
281 }
282 #endif
283 break;
284 }
285
286 NetworkAddress addr(runp->ai_addr, (int)runp->ai_addrlen);
287 (*sockets)[addr] = sock;
288 sock = INVALID_SOCKET;
289 }
290 freeaddrinfo (ai);
291
292 return sock;
293 }
294
295 /**
296 * Helper function to resolve a listening.
297 * @param runp information about the socket to try not
298 * @return the opened socket or INVALID_SOCKET
299 */
ListenLoopProc(addrinfo * runp)300 static SOCKET ListenLoopProc(addrinfo *runp)
301 {
302 std::string address = NetworkAddress(runp->ai_addr, (int)runp->ai_addrlen).GetAddressAsString();
303
304 SOCKET sock = socket(runp->ai_family, runp->ai_socktype, runp->ai_protocol);
305 if (sock == INVALID_SOCKET) {
306 const char *type = NetworkAddress::SocketTypeAsString(runp->ai_socktype);
307 const char *family = NetworkAddress::AddressFamilyAsString(runp->ai_family);
308 Debug(net, 0, "Could not create {} {} socket: {}", type, family, NetworkError::GetLast().AsString());
309 return INVALID_SOCKET;
310 }
311
312 if (runp->ai_socktype == SOCK_STREAM && !SetNoDelay(sock)) {
313 Debug(net, 1, "Setting no-delay mode failed: {}", NetworkError::GetLast().AsString());
314 }
315
316 if (!SetReusePort(sock)) {
317 Debug(net, 0, "Setting reuse-address mode failed: {}", NetworkError::GetLast().AsString());
318 }
319
320 #ifndef __OS2__
321 int on = 1;
322 if (runp->ai_family == AF_INET6 &&
323 setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, (const char*)&on, sizeof(on)) == -1) {
324 Debug(net, 3, "Could not disable IPv4 over IPv6: {}", NetworkError::GetLast().AsString());
325 }
326 #endif
327
328 if (bind(sock, runp->ai_addr, (int)runp->ai_addrlen) != 0) {
329 Debug(net, 0, "Could not bind socket on {}: {}", address, NetworkError::GetLast().AsString());
330 closesocket(sock);
331 return INVALID_SOCKET;
332 }
333
334 if (runp->ai_socktype != SOCK_DGRAM && listen(sock, 1) != 0) {
335 Debug(net, 0, "Could not listen on socket: {}", NetworkError::GetLast().AsString());
336 closesocket(sock);
337 return INVALID_SOCKET;
338 }
339
340 /* Connection succeeded */
341
342 if (!SetNonBlocking(sock)) {
343 Debug(net, 0, "Setting non-blocking mode failed: {}", NetworkError::GetLast().AsString());
344 }
345
346 Debug(net, 3, "Listening on {}", address);
347 return sock;
348 }
349
350 /**
351 * Make the given socket listen.
352 * @param socktype the type of socket (TCP, UDP, etc)
353 * @param sockets the list of sockets to add the sockets to
354 */
Listen(int socktype,SocketList * sockets)355 void NetworkAddress::Listen(int socktype, SocketList *sockets)
356 {
357 assert(sockets != nullptr);
358
359 /* Setting both hostname to "" and port to 0 is not allowed.
360 * As port 0 means bind to any port, the other must mean that
361 * we want to bind to 'all' IPs. */
362 if (this->address_length == 0 && this->address.ss_family == AF_UNSPEC &&
363 this->hostname.empty() && this->GetPort() == 0) {
364 this->Resolve(AF_INET, socktype, AI_ADDRCONFIG | AI_PASSIVE, sockets, ListenLoopProc);
365 this->Resolve(AF_INET6, socktype, AI_ADDRCONFIG | AI_PASSIVE, sockets, ListenLoopProc);
366 } else {
367 this->Resolve(AF_UNSPEC, socktype, AI_ADDRCONFIG | AI_PASSIVE, sockets, ListenLoopProc);
368 }
369 }
370
371 /**
372 * Convert the socket type into a string
373 * @param socktype the socket type to convert
374 * @return the string representation
375 * @note only works for SOCK_STREAM and SOCK_DGRAM
376 */
SocketTypeAsString(int socktype)377 /* static */ const char *NetworkAddress::SocketTypeAsString(int socktype)
378 {
379 switch (socktype) {
380 case SOCK_STREAM: return "tcp";
381 case SOCK_DGRAM: return "udp";
382 default: return "unsupported";
383 }
384 }
385
386 /**
387 * Convert the address family into a string
388 * @param family the family to convert
389 * @return the string representation
390 * @note only works for AF_INET, AF_INET6 and AF_UNSPEC
391 */
AddressFamilyAsString(int family)392 /* static */ const char *NetworkAddress::AddressFamilyAsString(int family)
393 {
394 switch (family) {
395 case AF_UNSPEC: return "either IPv4 or IPv6";
396 case AF_INET: return "IPv4";
397 case AF_INET6: return "IPv6";
398 default: return "unsupported";
399 }
400 }
401
402 /**
403 * Get the peer address of a socket as NetworkAddress.
404 * @param sock The socket to get the peer address of.
405 * @return The NetworkAddress of the peer address.
406 */
GetPeerAddress(SOCKET sock)407 /* static */ NetworkAddress NetworkAddress::GetPeerAddress(SOCKET sock)
408 {
409 sockaddr_storage addr = {};
410 socklen_t addr_len = sizeof(addr);
411 if (getpeername(sock, (sockaddr *)&addr, &addr_len) != 0) {
412 Debug(net, 0, "Failed to get address of the peer: {}", NetworkError::GetLast().AsString());
413 return NetworkAddress();
414 }
415 return NetworkAddress(addr, addr_len);
416 }
417
418 /**
419 * Get the local address of a socket as NetworkAddress.
420 * @param sock The socket to get the local address of.
421 * @return The NetworkAddress of the local address.
422 */
GetSockAddress(SOCKET sock)423 /* static */ NetworkAddress NetworkAddress::GetSockAddress(SOCKET sock)
424 {
425 sockaddr_storage addr = {};
426 socklen_t addr_len = sizeof(addr);
427 if (getsockname(sock, (sockaddr *)&addr, &addr_len) != 0) {
428 Debug(net, 0, "Failed to get address of the socket: {}", NetworkError::GetLast().AsString());
429 return NetworkAddress();
430 }
431 return NetworkAddress(addr, addr_len);
432 }
433
434 /**
435 * Get the peer name of a socket in string format.
436 * @param sock The socket to get the peer name of.
437 * @return The string representation of the peer name.
438 */
GetPeerName(SOCKET sock)439 /* static */ const std::string NetworkAddress::GetPeerName(SOCKET sock)
440 {
441 return NetworkAddress::GetPeerAddress(sock).GetAddressAsString();
442 }
443
444 /**
445 * Convert a string containing either "hostname", "hostname:port" or invite code
446 * to a ServerAddress, where the string can be postfixed with "#company" to
447 * indicate the requested company.
448 *
449 * @param connection_string The string to parse.
450 * @param default_port The default port to set port to if not in connection_string.
451 * @param company Pointer to the company variable to set iff indicated.
452 * @return A valid ServerAddress of the parsed information.
453 */
Parse(const std::string & connection_string,uint16 default_port,CompanyID * company_id)454 /* static */ ServerAddress ServerAddress::Parse(const std::string &connection_string, uint16 default_port, CompanyID *company_id)
455 {
456 if (StrStartsWith(connection_string, "+")) {
457 std::string_view invite_code = ParseCompanyFromConnectionString(connection_string, company_id);
458 return ServerAddress(SERVER_ADDRESS_INVITE_CODE, std::string(invite_code));
459 }
460
461 uint16 port = default_port;
462 std::string_view ip = ParseFullConnectionString(connection_string, port, company_id);
463 return ServerAddress(SERVER_ADDRESS_DIRECT, std::string(ip) + ":" + std::to_string(port));
464 }
465