/* net.c -- most of the network code Copyright (C) 1998-2005 Ivo Timmermans, 2000-2006 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. $Id$ */ #include "system.h" #include #include "utils.h" #include "splay_tree.h" #include "conf.h" #include "connection.h" #include "device.h" #include "graph.h" #include "logger.h" #include "meta.h" #include "net.h" #include "netutl.h" #include "process.h" #include "protocol.h" #include "subnet.h" #include "xalloc.h" /* Purge edges and subnets of unreachable nodes. Use carefully. */ void purge(void) { splay_node_t *nnode, *nnext, *enode, *enext, *snode, *snext; node_t *n; edge_t *e; subnet_t *s; cp(); ifdebug(PROTOCOL) logger(LOG_DEBUG, _("Purging unreachable nodes")); /* Remove all edges and subnets owned by unreachable nodes. */ for(nnode = node_tree->head; nnode; nnode = nnext) { nnext = nnode->next; n = nnode->data; if(!n->status.reachable) { ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Purging node %s (%s)"), n->name, n->hostname); for(snode = n->subnet_tree->head; snode; snode = snext) { snext = snode->next; s = snode->data; if(!tunnelserver) send_del_subnet(broadcast, s); subnet_del(n, s); } for(enode = n->edge_tree->head; enode; enode = enext) { enext = enode->next; e = enode->data; if(!tunnelserver) send_del_edge(broadcast, e); edge_del(e); } } } /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */ for(nnode = node_tree->head; nnode; nnode = nnext) { nnext = nnode->next; n = nnode->data; if(!n->status.reachable) { for(enode = edge_weight_tree->head; enode; enode = enext) { enext = enode->next; e = enode->data; if(e->to == n) break; } if(!enode) node_del(n); } } } /* Terminate a connection: - Close the socket - Remove associated edge and tell other connections about it if report = true - Check if we need to retry making an outgoing connection - Deactivate the host */ void terminate_connection(connection_t *c, bool report) { cp(); ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Closing connection with %s (%s)"), c->name, c->hostname); c->status.active = false; if(c->node) c->node->connection = NULL; if(c->socket) closesocket(c->socket); if(c->edge) { if(report && !tunnelserver) send_del_edge(broadcast, c->edge); edge_del(c->edge); /* Run MST and SSSP algorithms */ graph(); /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */ if(report && !c->node->status.reachable) { edge_t *e; e = lookup_edge(c->node, myself); if(e) { if(!tunnelserver) send_del_edge(broadcast, e); edge_del(e); } } } /* Check if this was our outgoing connection */ if(c->outgoing) retry_outgoing(c->outgoing); connection_del(c); } /* Check if the other end is active. If we have sent packets, but didn't receive any, then possibly the other end is dead. We send a PING request over the meta connection. If the other end does not reply in time, we consider them dead and close the connection. */ static void timeout_handler(int fd, short events, void *event) { splay_node_t *node, *next; connection_t *c; time_t now = time(NULL); cp(); for(node = connection_tree->head; node; node = next) { next = node->next; c = node->data; if(c->last_ping_time + pingtimeout < now) { if(c->status.active) { if(c->status.pinged) { ifdebug(CONNECTIONS) logger(LOG_INFO, _("%s (%s) didn't respond to PING in %ld seconds"), c->name, c->hostname, now - c->last_ping_time); terminate_connection(c, true); continue; } else if(c->last_ping_time + pinginterval < now) { send_ping(c); } } else { if(c->status.connecting) { ifdebug(CONNECTIONS) logger(LOG_WARNING, _("Timeout while connecting to %s (%s)"), c->name, c->hostname); c->status.connecting = false; closesocket(c->socket); do_outgoing_connection(c); } else { ifdebug(CONNECTIONS) logger(LOG_WARNING, _("Timeout from %s (%s) during authentication"), c->name, c->hostname); terminate_connection(c, false); continue; } } } } event_add(event, &(struct timeval){pingtimeout, 0}); } void handle_meta_connection_data(int fd, short events, void *data) { connection_t *c = data; int result; socklen_t len = sizeof(result); if(c->status.connecting) { c->status.connecting = false; getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len); if(!result) finish_connecting(c); else { ifdebug(CONNECTIONS) logger(LOG_DEBUG, _("Error while connecting to %s (%s): %s"), c->name, c->hostname, strerror(result)); closesocket(c->socket); do_outgoing_connection(c); return; } } if (!receive_meta(c)) { terminate_connection(c, c->status.active); return; } } static void sigterm_handler(int signal, short events, void *data) { logger(LOG_NOTICE, _("Got %s signal"), strsignal(signal)); event_loopexit(NULL); } static void sighup_handler(int signal, short events, void *data) { connection_t *c; splay_node_t *node, *next; char *fname; struct stat s; static time_t last_config_check = 0; logger(LOG_NOTICE, _("Got %s signal"), strsignal(signal)); /* Reread our own configuration file */ exit_configuration(&config_tree); init_configuration(&config_tree); if(!read_server_config()) { logger(LOG_ERR, _("Unable to reread configuration file, exitting.")); event_loopexit(NULL); return; } /* Close connections to hosts that have a changed or deleted host config file */ for(node = connection_tree->head; node; node = next) { c = node->data; next = node->next; if(c->outgoing) { free(c->outgoing->name); if(c->outgoing->ai) freeaddrinfo(c->outgoing->ai); free(c->outgoing); c->outgoing = NULL; } asprintf(&fname, "%s/hosts/%s", confbase, c->name); if(stat(fname, &s) || s.st_mtime > last_config_check) terminate_connection(c, c->status.active); free(fname); } last_config_check = time(NULL); /* Try to make outgoing connections */ try_outgoing_connections(); } static void sigalrm_handler(int signal, short events, void *data) { logger(LOG_NOTICE, _("Got %s signal"), strsignal(signal)); connection_t *c; splay_node_t *node; for(node = connection_tree->head; node; node = node->next) { c = node->data; if(c->outgoing && !c->node) { if(timeout_initialized(&c->outgoing->ev)) event_del(&c->outgoing->ev); if(c->status.connecting) close(c->socket); c->outgoing->timeout = 0; do_outgoing_connection(c); } } } /* this is where it all happens... */ int main_loop(void) { struct event timeout_event; struct event sighup_event; struct event sigterm_event; struct event sigquit_event; struct event sigalrm_event; cp(); timeout_set(&timeout_event, timeout_handler, &timeout_event); event_add(&timeout_event, &(struct timeval){pingtimeout, 0}); signal_set(&sighup_event, SIGHUP, sighup_handler, NULL); signal_add(&sighup_event, NULL); signal_set(&sigterm_event, SIGTERM, sigterm_handler, NULL); signal_add(&sigterm_event, NULL); signal_set(&sigquit_event, SIGQUIT, sigterm_handler, NULL); signal_add(&sigquit_event, NULL); signal_set(&sigalrm_event, SIGALRM, sigalrm_handler, NULL); signal_add(&sigalrm_event, NULL); if(event_loop(0) < 0) { logger(LOG_ERR, _("Error while waiting for input: %s"), strerror(errno)); return 1; } signal_del(&sighup_event); signal_del(&sigterm_event); signal_del(&sigquit_event); signal_del(&sigalrm_event); event_del(&timeout_event); return 0; }