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"
40 #define EINPROGRESS WSAEINPROGRESS
43 /* Needed on Mac OS/X */
45 #define SOL_TCP IPPROTO_TCP
48 int addressfamily = AF_UNSPEC;
50 int seconds_till_retry = 5;
52 listen_socket_t listen_socket[MAXSOCKETS];
54 list_t *outgoing_list = NULL;
58 static void configure_tcp(connection_t *c) {
62 int flags = fcntl(c->socket, F_GETFL);
64 if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
65 logger(LOG_ERR, "fcntl for %s: %s", c->hostname, strerror(errno));
68 unsigned long arg = 1;
70 if(ioctlsocket(c->socket, FIONBIO, &arg) != 0) {
71 logger(LOG_ERR, "ioctlsocket for %s: WSA error %d", c->hostname, WSAGetLastError());
75 #if defined(SOL_TCP) && defined(TCP_NODELAY)
77 setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
80 #if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
81 option = IPTOS_LOWDELAY;
82 setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
86 static bool bind_to_interface(int sd) {
89 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
92 #endif /* defined(SOL_SOCKET) && defined(SO_BINDTODEVICE) */
94 if(!get_config_string (lookup_config (config_tree, "BindToInterface"), &iface))
97 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
98 memset(&ifr, 0, sizeof(ifr));
99 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
100 ifr.ifr_ifrn.ifrn_name[IFNAMSIZ - 1] = 0;
102 status = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));
104 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
108 #else /* if !defined(SOL_SOCKET) || !defined(SO_BINDTODEVICE) */
109 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
115 static bool bind_to_address(connection_t *c) {
117 struct addrinfo *ai_list;
118 struct addrinfo *ai_ptr;
119 struct addrinfo ai_hints;
123 assert(c->socket >= 0);
126 if(!get_config_string(lookup_config(config_tree, "BindToAddress"),
130 assert(node != NULL);
132 memset(&ai_hints, 0, sizeof(ai_hints));
133 ai_hints.ai_family = c->address.sa.sa_family;
134 /* We're called from `do_outgoing_connection' only. */
135 ai_hints.ai_socktype = SOCK_STREAM;
136 ai_hints.ai_protocol = IPPROTO_TCP;
140 status = getaddrinfo(node, /* service = */ NULL,
141 &ai_hints, &ai_list);
144 logger(LOG_WARNING, "Error looking up %s port %s: %s",
145 node, "any", gai_strerror(status));
148 assert(ai_list != NULL);
151 for(ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
152 status = bind(c->socket,
153 ai_list->ai_addr, ai_list->ai_addrlen);
160 logger(LOG_ERR, "Can't bind to %s/tcp: %s", node,
162 } else ifdebug(CONNECTIONS) {
163 logger(LOG_DEBUG, "Successfully bound outgoing "
164 "TCP socket to %s", node);
168 freeaddrinfo(ai_list);
170 return status ? false : true;
173 int setup_listen_socket(const sockaddr_t *sa) {
179 nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
182 ifdebug(STATUS) logger(LOG_ERR, "Creating metasocket failed: %s", strerror(errno));
186 /* Optimize TCP settings */
189 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
191 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
192 if(sa->sa.sa_family == AF_INET6)
193 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
197 (lookup_config(config_tree, "BindToInterface"), &iface)) {
198 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
201 memset(&ifr, 0, sizeof(ifr));
202 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
204 if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
206 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
211 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
215 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
217 addrstr = sockaddr2hostname(sa);
218 logger(LOG_ERR, "Can't bind to %s/tcp: %s", addrstr,
226 logger(LOG_ERR, "System call `%s' failed: %s", "listen",
234 int setup_vpn_in_socket(const sockaddr_t *sa) {
239 nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
242 logger(LOG_ERR, "Creating UDP socket failed: %s", strerror(errno));
248 int flags = fcntl(nfd, F_GETFL);
250 if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
252 logger(LOG_ERR, "System call `%s' failed: %s", "fcntl",
259 unsigned long arg = 1;
260 if(ioctlsocket(nfd, FIONBIO, &arg) != 0) {
262 logger(LOG_ERR, "Call to `%s' failed: WSA error %d", "ioctlsocket",
270 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
272 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
273 if(sa->sa.sa_family == AF_INET6)
274 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
277 #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
278 if(myself->options & OPTION_PMTU_DISCOVERY) {
279 option = IP_PMTUDISC_DO;
280 setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, &option, sizeof(option));
284 #if defined(SOL_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
285 if(myself->options & OPTION_PMTU_DISCOVERY) {
286 option = IPV6_PMTUDISC_DO;
287 setsockopt(nfd, SOL_IPV6, IPV6_MTU_DISCOVER, &option, sizeof(option));
291 if (!bind_to_interface(nfd)) {
296 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
298 addrstr = sockaddr2hostname(sa);
299 logger(LOG_ERR, "Can't bind to %s/udp: %s", addrstr,
306 } /* int setup_vpn_in_socket */
308 void retry_outgoing(outgoing_t *outgoing) {
311 outgoing->timeout += 5;
313 if(outgoing->timeout > maxtimeout)
314 outgoing->timeout = maxtimeout;
317 event->handler = (event_handler_t) setup_outgoing_connection;
318 event->time = now + outgoing->timeout;
319 event->data = outgoing;
322 ifdebug(CONNECTIONS) logger(LOG_NOTICE,
323 "Trying to re-establish outgoing connection in %d seconds",
327 void finish_connecting(connection_t *c) {
328 ifdebug(CONNECTIONS) logger(LOG_INFO, "Connected to %s (%s)", c->name, c->hostname);
332 c->last_ping_time = now;
337 void do_outgoing_connection(connection_t *c) {
338 char *address, *port;
342 if(!c->outgoing->ai) {
343 if(!c->outgoing->cfg) {
344 ifdebug(CONNECTIONS) logger(LOG_ERR, "Could not set up a meta connection to %s",
346 c->status.remove = true;
347 retry_outgoing(c->outgoing);
351 get_config_string(c->outgoing->cfg, &address);
353 if(!get_config_string(lookup_config(c->config_tree, "Port"), &port))
354 xasprintf(&port, "655");
356 c->outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
360 c->outgoing->aip = c->outgoing->ai;
361 c->outgoing->cfg = lookup_config_next(c->config_tree, c->outgoing->cfg);
364 if(!c->outgoing->aip) {
366 freeaddrinfo(c->outgoing->ai);
367 c->outgoing->ai = NULL;
371 memcpy(&c->address, c->outgoing->aip->ai_addr, c->outgoing->aip->ai_addrlen);
372 c->outgoing->aip = c->outgoing->aip->ai_next;
377 c->hostname = sockaddr2hostname(&c->address);
379 ifdebug(CONNECTIONS) logger(LOG_INFO, "Trying to connect to %s (%s)", c->name,
382 c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
384 if(c->socket == -1) {
385 ifdebug(CONNECTIONS) logger(LOG_ERR, "Creating socket for %s failed: %s", c->hostname,
391 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
393 if(c->address.sa.sa_family == AF_INET6)
394 setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
397 bind_to_interface(c->socket);
400 /* Optimize TCP settings */
406 result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
409 if(errno == EINPROGRESS
410 #if defined(WIN32) && !defined(O_NONBLOCK)
411 || WSAGetLastError() == WSAEWOULDBLOCK
414 c->status.connecting = true;
418 closesocket(c->socket);
420 ifdebug(CONNECTIONS) logger(LOG_ERR, "%s: %s", c->hostname, strerror(errno));
425 finish_connecting(c);
430 void setup_outgoing_connection(outgoing_t *outgoing) {
434 n = lookup_node(outgoing->name);
438 ifdebug(CONNECTIONS) logger(LOG_INFO, "Already connected to %s", outgoing->name);
440 n->connection->outgoing = outgoing;
444 c = new_connection();
445 c->name = xstrdup(outgoing->name);
446 c->outcipher = myself->connection->outcipher;
447 c->outdigest = myself->connection->outdigest;
448 c->outmaclength = myself->connection->outmaclength;
449 c->outcompression = myself->connection->outcompression;
451 init_configuration(&c->config_tree);
452 read_connection_config(c);
454 outgoing->cfg = lookup_config(c->config_tree, "Address");
457 logger(LOG_ERR, "No address specified for %s", c->name);
462 c->outgoing = outgoing;
463 c->last_ping_time = now;
467 do_outgoing_connection(c);
471 accept a new tcp connect and create a
474 bool handle_new_meta_connection(int sock) {
478 socklen_t len = sizeof(sa);
480 fd = accept(sock, &sa.sa, &len);
483 logger(LOG_ERR, "Accepting a new connection failed: %s",
490 c = new_connection();
491 c->name = xstrdup("<unknown>");
492 c->outcipher = myself->connection->outcipher;
493 c->outdigest = myself->connection->outdigest;
494 c->outmaclength = myself->connection->outmaclength;
495 c->outcompression = myself->connection->outcompression;
498 c->hostname = sockaddr2hostname(&sa);
500 c->last_ping_time = now;
502 ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection from %s", c->hostname);
508 c->allow_request = ID;
514 void free_outgoing(outgoing_t *outgoing) {
516 freeaddrinfo(outgoing->ai);
519 free(outgoing->name);
524 void try_outgoing_connections(void) {
525 static config_t *cfg = NULL;
527 outgoing_t *outgoing;
532 for(node = connection_tree->head; node; node = node->next) {
537 list_delete_list(outgoing_list);
540 outgoing_list = list_alloc((list_action_t)free_outgoing);
542 for(cfg = lookup_config(config_tree, "ConnectTo"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
543 get_config_string(cfg, &name);
545 if(!check_id(name)) {
547 "Invalid name for outgoing connection in %s line %d",
548 cfg->file, cfg->line);
553 outgoing = xmalloc_and_zero(sizeof(*outgoing));
554 outgoing->name = name;
555 list_insert_tail(outgoing_list, outgoing);
556 setup_outgoing_connection(outgoing);