2 net_socket.c -- Handle various kinds of sockets.
3 Copyright (C) 1998-2005 Ivo Timmermans,
4 2000-2009 Guus Sliepen <guus@tinc-vpn.org>
5 2006 Scott Lamb <slamb@slamb.org>
6 2009 Florian Forster <octo@verplant.org>
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License along
19 with this program; if not, write to the Free Software Foundation, Inc.,
20 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include "connection.h"
39 /* Needed on Mac OS/X */
41 #define SOL_TCP IPPROTO_TCP
44 int addressfamily = AF_UNSPEC;
46 int seconds_till_retry = 5;
48 listen_socket_t listen_socket[MAXSOCKETS];
50 list_t *outgoing_list = NULL;
54 static void configure_tcp(connection_t *c) {
58 int flags = fcntl(c->socket, F_GETFL);
60 if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
61 logger(LOG_ERR, "fcntl for %s: %s", c->hostname, strerror(errno));
64 unsigned long arg = 1;
66 if(ioctlsocket(c->socket, FIONBIO, &arg) != 0) {
67 logger(LOG_ERR, "ioctlsocket for %s: %d", c->hostname, sockstrerror(sockerrno));
71 #if defined(SOL_TCP) && defined(TCP_NODELAY)
73 setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
76 #if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
77 option = IPTOS_LOWDELAY;
78 setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
82 static bool bind_to_interface(int sd) {
85 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
88 #endif /* defined(SOL_SOCKET) && defined(SO_BINDTODEVICE) */
90 if(!get_config_string (lookup_config (config_tree, "BindToInterface"), &iface))
93 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
94 memset(&ifr, 0, sizeof(ifr));
95 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
96 ifr.ifr_ifrn.ifrn_name[IFNAMSIZ - 1] = 0;
98 status = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));
100 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
104 #else /* if !defined(SOL_SOCKET) || !defined(SO_BINDTODEVICE) */
105 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
111 static bool bind_to_address(connection_t *c) {
113 struct addrinfo *ai_list;
114 struct addrinfo *ai_ptr;
115 struct addrinfo ai_hints;
119 assert(c->socket >= 0);
122 if(!get_config_string(lookup_config(config_tree, "BindToAddress"),
126 assert(node != NULL);
128 memset(&ai_hints, 0, sizeof(ai_hints));
129 ai_hints.ai_family = c->address.sa.sa_family;
130 /* We're called from `do_outgoing_connection' only. */
131 ai_hints.ai_socktype = SOCK_STREAM;
132 ai_hints.ai_protocol = IPPROTO_TCP;
136 status = getaddrinfo(node, /* service = */ NULL,
137 &ai_hints, &ai_list);
140 logger(LOG_WARNING, "Error looking up %s port %s: %s",
141 node, "any", gai_strerror(status));
144 assert(ai_list != NULL);
147 for(ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
148 status = bind(c->socket,
149 ai_list->ai_addr, ai_list->ai_addrlen);
156 logger(LOG_ERR, "Can't bind to %s/tcp: %s", node, sockstrerror(sockerrno));
157 } else ifdebug(CONNECTIONS) {
158 logger(LOG_DEBUG, "Successfully bound outgoing "
159 "TCP socket to %s", node);
163 freeaddrinfo(ai_list);
165 return status ? false : true;
168 int setup_listen_socket(const sockaddr_t *sa) {
174 nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
177 ifdebug(STATUS) logger(LOG_ERR, "Creating metasocket failed: %s", sockstrerror(sockerrno));
181 /* Optimize TCP settings */
184 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
186 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
187 if(sa->sa.sa_family == AF_INET6)
188 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
192 (lookup_config(config_tree, "BindToInterface"), &iface)) {
193 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
196 memset(&ifr, 0, sizeof(ifr));
197 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
199 if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
201 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
202 strerror(sockerrno));
206 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
210 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
212 addrstr = sockaddr2hostname(sa);
213 logger(LOG_ERR, "Can't bind to %s/tcp: %s", addrstr, sockstrerror(sockerrno));
220 logger(LOG_ERR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno));
227 int setup_vpn_in_socket(const sockaddr_t *sa) {
232 nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
235 logger(LOG_ERR, "Creating UDP socket failed: %s", sockstrerror(sockerrno));
241 int flags = fcntl(nfd, F_GETFL);
243 if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
245 logger(LOG_ERR, "System call `%s' failed: %s", "fcntl",
252 unsigned long arg = 1;
253 if(ioctlsocket(nfd, FIONBIO, &arg) != 0) {
255 logger(LOG_ERR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno));
262 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
264 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
265 if(sa->sa.sa_family == AF_INET6)
266 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
269 #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
270 if(myself->options & OPTION_PMTU_DISCOVERY) {
271 option = IP_PMTUDISC_DO;
272 setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, &option, sizeof(option));
274 #elif defined(IPPROTO_IP) && defined(IP_DONTFRAGMENT)
275 if(myself->options & OPTION_PMTU_DISCOVERY) {
277 setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, &option, sizeof(option));
281 #if defined(SOL_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
282 if(myself->options & OPTION_PMTU_DISCOVERY) {
283 option = IPV6_PMTUDISC_DO;
284 setsockopt(nfd, SOL_IPV6, IPV6_MTU_DISCOVER, &option, sizeof(option));
288 if (!bind_to_interface(nfd)) {
293 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
295 addrstr = sockaddr2hostname(sa);
296 logger(LOG_ERR, "Can't bind to %s/udp: %s", addrstr, sockstrerror(sockerrno));
302 } /* int setup_vpn_in_socket */
304 void retry_outgoing(outgoing_t *outgoing) {
305 outgoing->timeout += 5;
307 if(outgoing->timeout > maxtimeout)
308 outgoing->timeout = maxtimeout;
311 event_del(outgoing->event);
312 outgoing->event = new_event();
313 outgoing->event->handler = (event_handler_t) setup_outgoing_connection;
314 outgoing->event->time = now + outgoing->timeout;
315 outgoing->event->data = outgoing;
316 event_add(outgoing->event);
318 ifdebug(CONNECTIONS) logger(LOG_NOTICE,
319 "Trying to re-establish outgoing connection in %d seconds",
323 void finish_connecting(connection_t *c) {
324 ifdebug(CONNECTIONS) logger(LOG_INFO, "Connected to %s (%s)", c->name, c->hostname);
328 c->last_ping_time = now;
333 void do_outgoing_connection(connection_t *c) {
334 char *address, *port, *space;
338 logger(LOG_ERR, "do_outgoing_connection() for %s called without c->outgoing", c->name);
343 if(!c->outgoing->ai) {
344 if(!c->outgoing->cfg) {
345 ifdebug(CONNECTIONS) logger(LOG_ERR, "Could not set up a meta connection to %s",
347 c->status.remove = true;
348 retry_outgoing(c->outgoing);
353 get_config_string(c->outgoing->cfg, &address);
355 space = strchr(address, ' ');
357 port = xstrdup(space + 1);
360 if(!get_config_string(lookup_config(c->config_tree, "Port"), &port))
361 port = xstrdup("655");
364 c->outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
368 c->outgoing->aip = c->outgoing->ai;
369 c->outgoing->cfg = lookup_config_next(c->config_tree, c->outgoing->cfg);
372 if(!c->outgoing->aip) {
374 freeaddrinfo(c->outgoing->ai);
375 c->outgoing->ai = NULL;
379 memcpy(&c->address, c->outgoing->aip->ai_addr, c->outgoing->aip->ai_addrlen);
380 c->outgoing->aip = c->outgoing->aip->ai_next;
385 c->hostname = sockaddr2hostname(&c->address);
387 ifdebug(CONNECTIONS) logger(LOG_INFO, "Trying to connect to %s (%s)", c->name,
390 c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
392 if(c->socket == -1) {
393 ifdebug(CONNECTIONS) logger(LOG_ERR, "Creating socket for %s failed: %s", c->hostname, sockstrerror(sockerrno));
397 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
399 if(c->address.sa.sa_family == AF_INET6)
400 setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
403 bind_to_interface(c->socket);
406 /* Optimize TCP settings */
412 result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
415 if(sockinprogress(sockerrno)) {
416 c->status.connecting = true;
420 closesocket(c->socket);
422 ifdebug(CONNECTIONS) logger(LOG_ERR, "%s: %s", c->hostname, sockstrerror(sockerrno));
427 finish_connecting(c);
432 void setup_outgoing_connection(outgoing_t *outgoing) {
436 outgoing->event = NULL;
438 n = lookup_node(outgoing->name);
442 ifdebug(CONNECTIONS) logger(LOG_INFO, "Already connected to %s", outgoing->name);
444 n->connection->outgoing = outgoing;
448 c = new_connection();
449 c->name = xstrdup(outgoing->name);
450 c->outcipher = myself->connection->outcipher;
451 c->outdigest = myself->connection->outdigest;
452 c->outmaclength = myself->connection->outmaclength;
453 c->outcompression = myself->connection->outcompression;
455 init_configuration(&c->config_tree);
456 read_connection_config(c);
458 outgoing->cfg = lookup_config(c->config_tree, "Address");
461 logger(LOG_ERR, "No address specified for %s", c->name);
466 c->outgoing = outgoing;
467 c->last_ping_time = now;
471 do_outgoing_connection(c);
475 accept a new tcp connect and create a
478 bool handle_new_meta_connection(int sock) {
482 socklen_t len = sizeof(sa);
484 fd = accept(sock, &sa.sa, &len);
487 logger(LOG_ERR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
493 c = new_connection();
494 c->name = xstrdup("<unknown>");
495 c->outcipher = myself->connection->outcipher;
496 c->outdigest = myself->connection->outdigest;
497 c->outmaclength = myself->connection->outmaclength;
498 c->outcompression = myself->connection->outcompression;
501 c->hostname = sockaddr2hostname(&sa);
503 c->last_ping_time = now;
505 ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection from %s", c->hostname);
511 c->allow_request = ID;
517 void free_outgoing(outgoing_t *outgoing) {
519 freeaddrinfo(outgoing->ai);
522 free(outgoing->name);
527 void try_outgoing_connections(void) {
528 static config_t *cfg = NULL;
530 outgoing_t *outgoing;
532 outgoing_list = list_alloc((list_action_t)free_outgoing);
534 for(cfg = lookup_config(config_tree, "ConnectTo"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
535 get_config_string(cfg, &name);
537 if(!check_id(name)) {
539 "Invalid name for outgoing connection in %s line %d",
540 cfg->file, cfg->line);
545 outgoing = xmalloc_and_zero(sizeof(*outgoing));
546 outgoing->name = name;
547 list_insert_tail(outgoing_list, outgoing);
548 setup_outgoing_connection(outgoing);