2 net.c -- most of the network code
3 Copyright (C) 1998-2005 Ivo Timmermans,
4 2000-2010 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) {
62 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) {
92 if(!enode && (!strictsubnets || !n->subnet_tree->head))
93 /* in strictsubnets mode do not delete nodes with subnets */
100 Terminate a connection:
102 - Remove associated edge and tell other connections about it if report = true
103 - Check if we need to retry making an outgoing connection
104 - Deactivate the host
106 void terminate_connection(connection_t *c, bool report) {
107 ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)",
108 c->name, c->hostname);
110 c->status.active = false;
113 c->node->connection = NULL;
116 closesocket(c->socket);
119 if(report && !tunnelserver)
120 send_del_edge(broadcast, c->edge);
124 /* Run MST and SSSP algorithms */
128 /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
130 if(report && !c->node->status.reachable) {
132 e = lookup_edge(c->node, myself);
135 send_del_edge(broadcast, e);
141 /* Check if this was our outgoing connection */
144 retry_outgoing(c->outgoing);
150 Check if the other end is active.
151 If we have sent packets, but didn't receive any,
152 then possibly the other end is dead. We send a
153 PING request over the meta connection. If the other
154 end does not reply in time, we consider them dead
155 and close the connection.
157 static void timeout_handler(int fd, short events, void *event) {
158 splay_node_t *node, *next;
160 time_t now = time(NULL);
162 for(node = connection_tree->head; node; node = next) {
166 if(c->last_ping_time + pingtimeout < now) {
167 if(c->status.active) {
168 if(c->status.pinged) {
169 ifdebug(CONNECTIONS) logger(LOG_INFO, "%s (%s) didn't respond to PING in %ld seconds",
170 c->name, c->hostname, now - c->last_ping_time);
171 terminate_connection(c, true);
173 } else if(c->last_ping_time + pinginterval < now) {
177 if(c->status.connecting) {
179 logger(LOG_WARNING, "Timeout while connecting to %s (%s)", c->name, c->hostname);
180 c->status.connecting = false;
181 closesocket(c->socket);
182 do_outgoing_connection(c);
184 ifdebug(CONNECTIONS) logger(LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname);
185 terminate_connection(c, false);
192 event_add(event, &(struct timeval){pingtimeout, 0});
195 void handle_meta_connection_data(int fd, short events, void *data) {
196 connection_t *c = data;
198 socklen_t len = sizeof result;
200 if(c->status.connecting) {
201 c->status.connecting = false;
203 getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
206 finish_connecting(c);
208 ifdebug(CONNECTIONS) logger(LOG_DEBUG,
209 "Error while connecting to %s (%s): %s",
210 c->name, c->hostname, sockstrerror(result));
211 closesocket(c->socket);
212 do_outgoing_connection(c);
217 if (!receive_meta(c)) {
218 terminate_connection(c, c->status.active);
223 static void sigterm_handler(int signal, short events, void *data) {
224 logger(LOG_NOTICE, "Got %s signal", strsignal(signal));
225 event_loopexit(NULL);
228 static void sighup_handler(int signal, short events, void *data) {
229 logger(LOG_NOTICE, "Got %s signal", strsignal(signal));
230 reload_configuration();
233 int reload_configuration(void) {
235 splay_node_t *node, *next;
238 static time_t last_config_check = 0;
240 /* Reread our own configuration file */
242 exit_configuration(&config_tree);
243 init_configuration(&config_tree);
245 if(!read_server_config()) {
246 logger(LOG_ERR, "Unable to reread configuration file, exitting.");
247 event_loopexit(NULL);
251 /* Close connections to hosts that have a changed or deleted host config file */
253 for(node = connection_tree->head; node; node = next) {
258 free(c->outgoing->name);
260 freeaddrinfo(c->outgoing->ai);
265 xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
266 if(stat(fname, &s) || s.st_mtime > last_config_check)
267 terminate_connection(c, c->status.active);
271 last_config_check = time(NULL);
273 /* Try to make outgoing connections */
275 try_outgoing_connections();
284 for(node = connection_tree->head; node; node = node->next) {
287 if(c->outgoing && !c->node) {
288 if(timeout_initialized(&c->outgoing->ev))
289 event_del(&c->outgoing->ev);
290 if(c->status.connecting)
292 c->outgoing->timeout = 0;
293 do_outgoing_connection(c);
299 this is where it all happens...
301 int main_loop(void) {
302 struct event timeout_event;
303 struct event sighup_event;
304 struct event sigterm_event;
305 struct event sigquit_event;
307 timeout_set(&timeout_event, timeout_handler, &timeout_event);
308 event_add(&timeout_event, &(struct timeval){pingtimeout, 0});
311 signal_set(&sighup_event, SIGHUP, sighup_handler, NULL);
312 signal_add(&sighup_event, NULL);
315 signal_set(&sigterm_event, SIGTERM, sigterm_handler, NULL);
316 signal_add(&sigterm_event, NULL);
319 signal_set(&sigquit_event, SIGQUIT, sigterm_handler, NULL);
320 signal_add(&sigquit_event, NULL);
323 if(event_loop(0) < 0) {
324 logger(LOG_ERR, "Error while waiting for input: %s", strerror(errno));
328 signal_del(&sighup_event);
329 signal_del(&sigterm_event);
330 signal_del(&sigquit_event);
331 event_del(&timeout_event);