2 net.c -- most of the network code
3 Copyright (C) 1998-2005 Ivo Timmermans,
4 2000-2009 Guus Sliepen <guus@tinc-vpn.org>
5 2006 Scott Lamb <slamb@slamb.org>
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License along
18 with this program; if not, write to the Free Software Foundation, Inc.,
19 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 #include "splay_tree.h"
27 #include "connection.h"
39 /* Purge edges and subnets of unreachable nodes. Use carefully. */
42 splay_node_t *nnode, *nnext, *enode, *enext, *snode, *snext;
47 ifdebug(PROTOCOL) logger(LOG_DEBUG, "Purging unreachable nodes");
49 /* Remove all edges and subnets owned by unreachable nodes. */
51 for(nnode = node_tree->head; nnode; nnode = nnext) {
55 if(!n->status.reachable) {
56 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Purging node %s (%s)", n->name,
59 for(snode = n->subnet_tree->head; snode; snode = snext) {
63 send_del_subnet(broadcast, s);
67 for(enode = n->edge_tree->head; enode; enode = enext) {
71 send_del_edge(broadcast, e);
77 /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */
79 for(nnode = node_tree->head; nnode; nnode = nnext) {
83 if(!n->status.reachable) {
84 for(enode = edge_weight_tree->head; enode; enode = enext) {
99 Terminate a connection:
101 - Remove associated edge and tell other connections about it if report = true
102 - Check if we need to retry making an outgoing connection
103 - Deactivate the host
105 void terminate_connection(connection_t *c, bool report) {
106 ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)",
107 c->name, c->hostname);
109 c->status.active = false;
112 c->node->connection = NULL;
115 closesocket(c->socket);
118 if(report && !tunnelserver)
119 send_del_edge(broadcast, c->edge);
123 /* Run MST and SSSP algorithms */
127 /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
129 if(report && !c->node->status.reachable) {
131 e = lookup_edge(c->node, myself);
134 send_del_edge(broadcast, e);
140 /* Check if this was our outgoing connection */
143 retry_outgoing(c->outgoing);
149 Check if the other end is active.
150 If we have sent packets, but didn't receive any,
151 then possibly the other end is dead. We send a
152 PING request over the meta connection. If the other
153 end does not reply in time, we consider them dead
154 and close the connection.
156 static void timeout_handler(int fd, short events, void *event) {
157 splay_node_t *node, *next;
159 time_t now = time(NULL);
161 for(node = connection_tree->head; node; node = next) {
165 if(c->last_ping_time + pingtimeout < now) {
166 if(c->status.active) {
167 if(c->status.pinged) {
168 ifdebug(CONNECTIONS) logger(LOG_INFO, "%s (%s) didn't respond to PING in %ld seconds",
169 c->name, c->hostname, now - c->last_ping_time);
170 terminate_connection(c, true);
172 } else if(c->last_ping_time + pinginterval < now) {
176 if(c->status.connecting) {
178 logger(LOG_WARNING, "Timeout while connecting to %s (%s)", c->name, c->hostname);
179 c->status.connecting = false;
180 closesocket(c->socket);
181 do_outgoing_connection(c);
183 ifdebug(CONNECTIONS) logger(LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname);
184 terminate_connection(c, false);
191 event_add(event, &(struct timeval){pingtimeout, 0});
194 void handle_meta_connection_data(int fd, short events, void *data) {
195 connection_t *c = data;
197 socklen_t len = sizeof result;
199 if(c->status.connecting) {
200 c->status.connecting = false;
202 getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
205 finish_connecting(c);
207 ifdebug(CONNECTIONS) logger(LOG_DEBUG,
208 "Error while connecting to %s (%s): %s",
209 c->name, c->hostname, sockstrerror(result));
210 closesocket(c->socket);
211 do_outgoing_connection(c);
216 if (!receive_meta(c)) {
217 terminate_connection(c, c->status.active);
222 static void sigterm_handler(int signal, short events, void *data) {
223 logger(LOG_NOTICE, "Got %s signal", strsignal(signal));
224 event_loopexit(NULL);
227 static void sighup_handler(int signal, short events, void *data) {
228 logger(LOG_NOTICE, "Got %s signal", strsignal(signal));
229 reload_configuration();
232 int reload_configuration(void) {
234 splay_node_t *node, *next;
237 static time_t last_config_check = 0;
239 /* Reread our own configuration file */
241 exit_configuration(&config_tree);
242 init_configuration(&config_tree);
244 if(!read_server_config()) {
245 logger(LOG_ERR, "Unable to reread configuration file, exitting.");
246 event_loopexit(NULL);
250 /* Close connections to hosts that have a changed or deleted host config file */
252 for(node = connection_tree->head; node; node = next) {
257 free(c->outgoing->name);
259 freeaddrinfo(c->outgoing->ai);
264 xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
265 if(stat(fname, &s) || s.st_mtime > last_config_check)
266 terminate_connection(c, c->status.active);
270 last_config_check = time(NULL);
272 /* Try to make outgoing connections */
274 try_outgoing_connections();
283 for(node = connection_tree->head; node; node = node->next) {
286 if(c->outgoing && !c->node) {
287 if(timeout_initialized(&c->outgoing->ev))
288 event_del(&c->outgoing->ev);
289 if(c->status.connecting)
291 c->outgoing->timeout = 0;
292 do_outgoing_connection(c);
298 this is where it all happens...
300 int main_loop(void) {
301 struct event timeout_event;
302 struct event sighup_event;
303 struct event sigterm_event;
304 struct event sigquit_event;
306 timeout_set(&timeout_event, timeout_handler, &timeout_event);
307 event_add(&timeout_event, &(struct timeval){pingtimeout, 0});
310 signal_set(&sighup_event, SIGHUP, sighup_handler, NULL);
311 signal_add(&sighup_event, NULL);
314 signal_set(&sigterm_event, SIGTERM, sigterm_handler, NULL);
315 signal_add(&sigterm_event, NULL);
318 signal_set(&sigquit_event, SIGQUIT, sigterm_handler, NULL);
319 signal_add(&sigquit_event, NULL);
322 if(event_loop(0) < 0) {
323 logger(LOG_ERR, "Error while waiting for input: %s", strerror(errno));
327 signal_del(&sighup_event);
328 signal_del(&sigterm_event);
329 signal_del(&sigquit_event);
330 event_del(&timeout_event);