2 net_socket.c -- Handle various kinds of sockets.
3 Copyright (C) 1998-2005 Ivo Timmermans,
4 2000-2012 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.
25 #include "splay_tree.h"
27 #include "connection.h"
36 /* Needed on Mac OS/X */
38 #define SOL_TCP IPPROTO_TCP
41 int addressfamily = AF_UNSPEC;
43 int seconds_till_retry = 5;
47 listen_socket_t listen_socket[MAXSOCKETS];
49 list_t *outgoing_list = NULL;
53 static void configure_tcp(connection_t *c) {
57 int flags = fcntl(c->socket, F_GETFL);
59 if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
60 logger(LOG_ERR, "fcntl for %s: %s", c->hostname, strerror(errno));
63 unsigned long arg = 1;
65 if(ioctlsocket(c->socket, FIONBIO, &arg) != 0) {
66 logger(LOG_ERR, "ioctlsocket for %s: %d", c->hostname, sockstrerror(sockerrno));
70 #if defined(SOL_TCP) && defined(TCP_NODELAY)
72 setsockopt(c->socket, SOL_TCP, TCP_NODELAY, (void *)&option, sizeof option);
75 #if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
76 option = IPTOS_LOWDELAY;
77 setsockopt(c->socket, SOL_IP, IP_TOS, (void *)&option, sizeof option);
81 static bool bind_to_interface(int sd) {
84 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
87 #endif /* defined(SOL_SOCKET) && defined(SO_BINDTODEVICE) */
89 if(!get_config_string (lookup_config (config_tree, "BindToInterface"), &iface))
92 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
93 memset(&ifr, 0, sizeof(ifr));
94 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
95 ifr.ifr_ifrn.ifrn_name[IFNAMSIZ - 1] = 0;
97 status = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof(ifr));
99 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
103 #else /* if !defined(SOL_SOCKET) || !defined(SO_BINDTODEVICE) */
104 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
110 int setup_listen_socket(const sockaddr_t *sa) {
116 nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
119 ifdebug(STATUS) logger(LOG_ERR, "Creating metasocket failed: %s", sockstrerror(sockerrno));
124 fcntl(nfd, F_SETFD, FD_CLOEXEC);
127 /* Optimize TCP settings */
130 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof option);
132 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
133 if(sa->sa.sa_family == AF_INET6)
134 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
138 (lookup_config(config_tree, "BindToInterface"), &iface)) {
139 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
142 memset(&ifr, 0, sizeof ifr);
143 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
145 if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof ifr)) {
147 logger(LOG_ERR, "Can't bind to interface %s: %s", iface,
148 strerror(sockerrno));
152 logger(LOG_WARNING, "%s not supported on this platform", "BindToInterface");
156 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
158 addrstr = sockaddr2hostname(sa);
159 logger(LOG_ERR, "Can't bind to %s/tcp: %s", addrstr, sockstrerror(sockerrno));
166 logger(LOG_ERR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno));
173 int setup_vpn_in_socket(const sockaddr_t *sa) {
178 nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
181 logger(LOG_ERR, "Creating UDP socket failed: %s", sockstrerror(sockerrno));
186 fcntl(nfd, F_SETFD, FD_CLOEXEC);
191 int flags = fcntl(nfd, F_GETFL);
193 if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
195 logger(LOG_ERR, "System call `%s' failed: %s", "fcntl",
202 unsigned long arg = 1;
203 if(ioctlsocket(nfd, FIONBIO, &arg) != 0) {
205 logger(LOG_ERR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno));
212 setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof option);
214 if(udp_rcvbuf && setsockopt(nfd, SOL_SOCKET, SO_RCVBUF, (void *)&udp_rcvbuf, sizeof(udp_rcvbuf)))
215 logger(LOG_WARNING, "Can't set UDP SO_RCVBUF to %i: %s", udp_rcvbuf, strerror(errno));
217 if(udp_sndbuf && setsockopt(nfd, SOL_SOCKET, SO_SNDBUF, (void *)&udp_sndbuf, sizeof(udp_sndbuf)))
218 logger(LOG_WARNING, "Can't set UDP SO_SNDBUF to %i: %s", udp_sndbuf, strerror(errno));
220 #if defined(IPPROTO_IPV6) && defined(IPV6_V6ONLY)
221 if(sa->sa.sa_family == AF_INET6)
222 setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
225 #if defined(IP_DONTFRAG) && !defined(IP_DONTFRAGMENT)
226 #define IP_DONTFRAGMENT IP_DONTFRAG
229 #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
230 if(myself->options & OPTION_PMTU_DISCOVERY) {
231 option = IP_PMTUDISC_DO;
232 setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option));
234 #elif defined(IPPROTO_IP) && defined(IP_DONTFRAGMENT)
235 if(myself->options & OPTION_PMTU_DISCOVERY) {
237 setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option));
240 #warning No way to disable IPv4 fragmentation
243 #if defined(SOL_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
244 if(myself->options & OPTION_PMTU_DISCOVERY) {
245 option = IPV6_PMTUDISC_DO;
246 setsockopt(nfd, SOL_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option));
248 #elif defined(IPPROTO_IPV6) && defined(IPV6_DONTFRAG)
249 if(myself->options & OPTION_PMTU_DISCOVERY) {
251 setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option));
254 #warning No way to disable IPv6 fragmentation
257 if (!bind_to_interface(nfd)) {
262 if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
264 addrstr = sockaddr2hostname(sa);
265 logger(LOG_ERR, "Can't bind to %s/udp: %s", addrstr, sockstrerror(sockerrno));
271 } /* int setup_vpn_in_socket */
273 static void retry_outgoing_handler(int fd, short events, void *data) {
274 setup_outgoing_connection(data);
277 void retry_outgoing(outgoing_t *outgoing) {
278 outgoing->timeout += 5;
280 if(outgoing->timeout > maxtimeout)
281 outgoing->timeout = maxtimeout;
283 timeout_set(&outgoing->ev, retry_outgoing_handler, outgoing);
284 event_add(&outgoing->ev, &(struct timeval){outgoing->timeout, 0});
286 ifdebug(CONNECTIONS) logger(LOG_NOTICE,
287 "Trying to re-establish outgoing connection in %d seconds",
291 void finish_connecting(connection_t *c) {
292 ifdebug(CONNECTIONS) logger(LOG_INFO, "Connected to %s (%s)", c->name, c->hostname);
296 c->last_ping_time = time(NULL);
297 c->status.connecting = false;
302 bool do_outgoing_connection(connection_t *c) {
303 char *address, *port, *space;
307 logger(LOG_ERR, "do_outgoing_connection() for %s called without c->outgoing", c->name);
312 if(!c->outgoing->ai) {
313 if(!c->outgoing->cfg) {
314 ifdebug(CONNECTIONS) logger(LOG_ERR, "Could not set up a meta connection to %s",
316 retry_outgoing(c->outgoing);
322 get_config_string(c->outgoing->cfg, &address);
324 space = strchr(address, ' ');
326 port = xstrdup(space + 1);
329 if(!get_config_string(lookup_config(c->config_tree, "Port"), &port))
330 port = xstrdup("655");
333 c->outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
337 c->outgoing->aip = c->outgoing->ai;
338 c->outgoing->cfg = lookup_config_next(c->config_tree, c->outgoing->cfg);
341 if(!c->outgoing->aip) {
343 freeaddrinfo(c->outgoing->ai);
344 c->outgoing->ai = NULL;
348 memcpy(&c->address, c->outgoing->aip->ai_addr, c->outgoing->aip->ai_addrlen);
349 c->outgoing->aip = c->outgoing->aip->ai_next;
354 c->hostname = sockaddr2hostname(&c->address);
356 ifdebug(CONNECTIONS) logger(LOG_INFO, "Trying to connect to %s (%s)", c->name,
359 c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
362 fcntl(c->socket, F_SETFD, FD_CLOEXEC);
365 if(c->socket == -1) {
366 ifdebug(CONNECTIONS) logger(LOG_ERR, "Creating socket for %s failed: %s", c->hostname, sockstrerror(sockerrno));
370 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
372 if(c->address.sa.sa_family == AF_INET6)
373 setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
376 bind_to_interface(c->socket);
378 /* Optimize TCP settings */
384 result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
387 if(sockinprogress(sockerrno)) {
388 c->status.connecting = true;
392 closesocket(c->socket);
394 ifdebug(CONNECTIONS) logger(LOG_ERR, "%s: %s", c->hostname, sockstrerror(sockerrno));
399 finish_connecting(c);
404 static void handle_meta_write(int sock, short events, void *data) {
405 ifdebug(META) logger(LOG_DEBUG, "handle_meta_write() called");
407 connection_t *c = data;
409 ssize_t outlen = send(c->socket, c->outbuf.data + c->outbuf.offset, c->outbuf.len - c->outbuf.offset, 0);
411 logger(LOG_ERR, "Onoes, outlen = %d (%s)", (int)outlen, strerror(errno));
412 terminate_connection(c, c->status.active);
416 buffer_read(&c->outbuf, outlen);
417 if(!c->outbuf.len && event_initialized(&c->outevent))
418 event_del(&c->outevent);
421 void setup_outgoing_connection(outgoing_t *outgoing) {
425 if(event_initialized(&outgoing->ev))
426 event_del(&outgoing->ev);
428 n = lookup_node(outgoing->name);
432 ifdebug(CONNECTIONS) logger(LOG_INFO, "Already connected to %s", outgoing->name);
434 n->connection->outgoing = outgoing;
438 c = new_connection();
439 c->name = xstrdup(outgoing->name);
440 c->outcipher = myself->connection->outcipher;
441 c->outdigest = myself->connection->outdigest;
442 c->outmaclength = myself->connection->outmaclength;
443 c->outcompression = myself->connection->outcompression;
445 init_configuration(&c->config_tree);
446 read_connection_config(c);
448 outgoing->cfg = lookup_config(c->config_tree, "Address");
451 logger(LOG_ERR, "No address specified for %s", c->name);
456 c->outgoing = outgoing;
457 c->last_ping_time = time(NULL);
461 if (do_outgoing_connection(c)) {
462 event_set(&c->inevent, c->socket, EV_READ | EV_PERSIST, handle_meta_connection_data, c);
463 event_set(&c->outevent, c->socket, EV_WRITE | EV_PERSIST, handle_meta_write, c);
464 event_add(&c->inevent, NULL);
469 accept a new tcp connect and create a
472 void handle_new_meta_connection(int sock, short events, void *data) {
476 socklen_t len = sizeof sa;
478 fd = accept(sock, &sa.sa, &len);
481 logger(LOG_ERR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
487 c = new_connection();
488 c->name = xstrdup("<unknown>");
489 c->outcipher = myself->connection->outcipher;
490 c->outdigest = myself->connection->outdigest;
491 c->outmaclength = myself->connection->outmaclength;
492 c->outcompression = myself->connection->outcompression;
495 c->hostname = sockaddr2hostname(&sa);
497 c->last_ping_time = time(NULL);
499 ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection from %s", c->hostname);
501 event_set(&c->inevent, c->socket, EV_READ | EV_PERSIST, handle_meta_connection_data, c);
502 event_set(&c->outevent, c->socket, EV_WRITE | EV_PERSIST, handle_meta_write, c);
503 event_add(&c->inevent, NULL);
509 c->allow_request = ID;
513 static void free_outgoing(outgoing_t *outgoing) {
515 freeaddrinfo(outgoing->ai);
518 free(outgoing->name);
523 void try_outgoing_connections(void) {
524 static config_t *cfg = NULL;
526 outgoing_t *outgoing;
528 outgoing_list = list_alloc((list_action_t)free_outgoing);
530 for(cfg = lookup_config(config_tree, "ConnectTo"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
531 get_config_string(cfg, &name);
533 if(!check_id(name)) {
535 "Invalid name for outgoing connection in %s line %d",
536 cfg->file, cfg->line);
541 outgoing = xmalloc_and_zero(sizeof *outgoing);
542 outgoing->name = name;
543 list_insert_tail(outgoing_list, outgoing);
544 setup_outgoing_connection(outgoing);