X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet.c;h=8ee782145cbd9b28a5d12734b50022db2dffd7ce;hb=fc119fb0096a9221f2cff279b07c886bcd794d28;hp=c56fe98d670d552b2aa33a08c954b3cea5385587;hpb=6f9f6779e6bd1dd7bb795b42dad550863a386ca8;p=tinc diff --git a/src/net.c b/src/net.c index c56fe98d..8a63615d 100644 --- a/src/net.c +++ b/src/net.c @@ -1,7 +1,9 @@ /* net.c -- most of the network code - Copyright (C) 1998-2002 Ivo Timmermans , - 2000-2002 Guus Sliepen + Copyright (C) 1998-2005 Ivo Timmermans, + 2000-2013 Guus Sliepen + 2006 Scott Lamb + 2011 Loïc Grenié 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 @@ -13,196 +15,119 @@ 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: net.c,v 1.35.4.181 2002/09/09 22:32:39 guus Exp $ + 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., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#include "config.h" - -#include -#include -#include -#include -#ifdef HAVE_NETINET_IN_SYSTM_H -#include -#endif -#ifdef HAVE_NETINET_IP_H -#include -#endif -#ifdef HAVE_NETINET_TCP_H -#include -#endif -#include -#include -#include -#include -#include -#include -#include -#include -#include -/* SunOS really wants sys/socket.h BEFORE net/if.h, - and FreeBSD wants these lines below the rest. */ -#include -#include -#include - -#include - -#include -#include -#include -#include +#include "system.h" +#include "utils.h" #include "conf.h" #include "connection.h" +#include "device.h" +#include "graph.h" +#include "logger.h" #include "meta.h" +#include "names.h" #include "net.h" #include "netutl.h" #include "process.h" #include "protocol.h" #include "subnet.h" -#include "graph.h" -#include "process.h" -#include "route.h" -#include "device.h" -#include "event.h" - -#include "system.h" - -#ifndef HAVE_RAND_PSEUDO_BYTES -#define RAND_pseudo_bytes RAND_bytes -#endif +#include "xalloc.h" -int do_purge = 0; -int sighup = 0; -int sigalrm = 0; - -time_t now = 0; +int contradicting_add_edge = 0; +int contradicting_del_edge = 0; +static int sleeptime = 10; +time_t last_config_check = 0; /* Purge edges and subnets of unreachable nodes. Use carefully. */ -void purge(void) -{ - avl_node_t *nnode, *nnext, *enode, *enext, *snode, *snext; - node_t *n; - edge_t *e; - subnet_t *s; - - cp(); +void purge(void) { + logger(DEBUG_PROTOCOL, LOG_DEBUG, "Purging unreachable nodes"); - if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Purging unreachable nodes")); - - for(nnode = node_tree->head; nnode; nnode = nnext) { - nnext = nnode->next; - n = (node_t *) nnode->data; + /* Remove all edges and subnets owned by unreachable nodes. */ + for splay_each(node_t, n, node_tree) { if(!n->status.reachable) { - if(debug_lvl >= DEBUG_SCARY_THINGS) - syslog(LOG_DEBUG, _("Purging node %s (%s)"), n->name, - n->hostname); - - for(snode = n->subnet_tree->head; snode; snode = snext) { - snext = snode->next; - s = (subnet_t *) snode->data; - send_del_subnet(broadcast, s); - subnet_del(n, s); + logger(DEBUG_SCARY_THINGS, LOG_DEBUG, "Purging node %s (%s)", n->name, n->hostname); + + for splay_each(subnet_t, s, n->subnet_tree) { + send_del_subnet(everyone, s); + if(!strictsubnets) + subnet_del(n, s); } - for(enode = n->edge_tree->head; enode; enode = enext) { - enext = enode->next; - e = (edge_t *) enode->data; - send_del_edge(broadcast, e); + for splay_each(edge_t, e, n->edge_tree) { + if(!tunnelserver) + send_del_edge(everyone, e); edge_del(e); } - - node_del(n); } } -} -/* - put all file descriptors in an fd_set array - While we're at it, purge stuff that needs to be removed. -*/ -void build_fdset(fd_set * fs) -{ - avl_node_t *node, *next; - connection_t *c; - int i; - - cp(); - - FD_ZERO(fs); - - for(node = connection_tree->head; node; node = next) { - next = node->next; - c = (connection_t *) node->data; - - if(c->status.remove) { - connection_del(c); - if(!connection_tree->head) - purge(); - } else - FD_SET(c->socket, fs); - } + /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */ - for(i = 0; i < listen_sockets; i++) { - FD_SET(listen_socket[i].tcp, fs); - FD_SET(listen_socket[i].udp, fs); - } + for splay_each(node_t, n, node_tree) { + if(!n->status.reachable) { + for splay_each(edge_t, e, edge_weight_tree) + if(e->to == n) + return; - FD_SET(device_fd, fs); + if(!autoconnect && (!strictsubnets || !n->subnet_tree->head)) + /* in strictsubnets mode do not delete nodes with subnets */ + node_del(n); + } + } } /* Terminate a connection: - - Close the socket - - Remove associated edge and tell other connections about it if report = 1 + - Mark it as inactive + - Remove the edge representing this connection + - Kill it with fire - Check if we need to retry making an outgoing connection - - Deactivate the host */ -void terminate_connection(connection_t *c, int report) -{ - cp(); +void terminate_connection(connection_t *c, bool report) { + logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Closing connection with %s (%s)", c->name, c->hostname); - if(c->status.remove) - return; + c->status.active = false; - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Closing connection with %s (%s)"), - c->name, c->hostname); - - c->status.remove = 1; - c->status.active = 0; - - if(c->node) + if(c->node && c->node->connection == c) c->node->connection = NULL; - if(c->socket) - close(c->socket); - if(c->edge) { - if(report) - send_del_edge(broadcast, c->edge); + if(report && !tunnelserver) + send_del_edge(everyone, c->edge); edge_del(c->edge); + c->edge = NULL; /* 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(everyone, e); + edge_del(e); + } + } } + outgoing_t *outgoing = c->outgoing; + connection_del(c); + /* Check if this was our outgoing connection */ - if(c->outgoing) { - retry_outgoing(c->outgoing); - c->outgoing = NULL; - } + if(outgoing) + do_outgoing_connection(outgoing); } /* @@ -213,208 +138,329 @@ void terminate_connection(connection_t *c, int report) end does not reply in time, we consider them dead and close the connection. */ -void check_dead_connections(void) -{ - avl_node_t *node, *next; - connection_t *c; - - cp(); - - for(node = connection_tree->head; node; node = next) { - next = node->next; - c = (connection_t *) node->data; +static void timeout_handler(void *data) { + for list_each(connection_t, c, connection_list) { + if(c->status.control) + continue; - if(c->last_ping_time + pingtimeout < now) { + if(c->last_ping_time + pingtimeout <= now.tv_sec) { if(c->status.active) { if(c->status.pinged) { - if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_INFO, _("%s (%s) didn't respond to PING"), - c->name, c->hostname); - c->status.timeout = 1; - terminate_connection(c, 1); - } else { + logger(DEBUG_CONNECTIONS, LOG_INFO, "%s (%s) didn't respond to PING in %ld seconds", c->name, c->hostname, (long)now.tv_sec - c->last_ping_time); + } else if(c->last_ping_time + pinginterval <= now.tv_sec) { send_ping(c); - } - } else { - if(c->status.remove) { - syslog(LOG_WARNING, _("Old connection_t for %s (%s) status %04x still lingering, deleting..."), - c->name, c->hostname, c->status); - connection_del(c); + continue; + } else { continue; } - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_WARNING, _("Timeout from %s (%s) during authentication"), - c->name, c->hostname); - terminate_connection(c, 0); + } else { + if(c->status.connecting) + logger(DEBUG_CONNECTIONS, LOG_WARNING, "Timeout while connecting to %s (%s)", c->name, c->hostname); + else + logger(DEBUG_CONNECTIONS, LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname); } + terminate_connection(c, c->status.active); } } + + timeout_set(data, &(struct timeval){pingtimeout, rand() % 100000}); } -/* - check all connections to see if anything - happened on their sockets -*/ -void check_network_activity(fd_set * f) -{ - connection_t *c; - avl_node_t *node; - int result, i; - int len = sizeof(result); - vpn_packet_t packet; - - cp(); - - if(FD_ISSET(device_fd, f)) { - if(!read_packet(&packet)) - route_outgoing(&packet); +static void periodic_handler(void *data) { + /* Check if there are too many contradicting ADD_EDGE and DEL_EDGE messages. + This usually only happens when another node has the same Name as this node. + If so, sleep for a short while to prevent a storm of contradicting messages. + */ + + if(contradicting_del_edge > 100 && contradicting_add_edge > 100) { + logger(DEBUG_ALWAYS, LOG_WARNING, "Possible node with same Name as us! Sleeping %d seconds.", sleeptime); + usleep(sleeptime * 1000000LL); + sleeptime *= 2; + if(sleeptime < 0) + sleeptime = 3600; + } else { + sleeptime /= 2; + if(sleeptime < 10) + sleeptime = 10; } - for(node = connection_tree->head; node; node = node->next) { - c = (connection_t *) node->data; + contradicting_add_edge = 0; + contradicting_del_edge = 0; - if(c->status.remove) - continue; + /* If AutoConnect is set, check if we need to make or break connections. */ + + if(autoconnect && node_tree->count > 1) { + /* Count number of active connections */ + int nc = 0; + for list_each(connection_t, c, connection_list) { + if(c->status.active && !c->status.control) + nc++; + } - if(FD_ISSET(c->socket, f)) { - if(c->status.connecting) { - c->status.connecting = 0; - getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len); - - if(!result) - finish_connecting(c); - else { - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_DEBUG, - _("Error while connecting to %s (%s): %s"), - c->name, c->hostname, strerror(result)); - close(c->socket); - do_outgoing_connection(c); + if(nc < autoconnect) { + /* Not enough active connections, try to add one. + Choose a random node, if we don't have a connection to it, + and we are not already trying to make one, create an + outgoing connection to this node. + */ + int r = rand() % node_tree->count; + int i = 0; + + for splay_each(node_t, n, node_tree) { + if(i++ != r) continue; + + if(n->connection) + break; + + bool found = false; + + for list_each(outgoing_t, outgoing, outgoing_list) { + if(!strcmp(outgoing->name, n->name)) { + found = true; + break; + } } + + if(!found) { + logger(DEBUG_CONNECTIONS, LOG_INFO, "Autoconnecting to %s", n->name); + outgoing_t *outgoing = xzalloc(sizeof *outgoing); + outgoing->name = xstrdup(n->name); + list_insert_tail(outgoing_list, outgoing); + setup_outgoing_connection(outgoing); + } + break; } + } else if(nc > autoconnect) { + /* Too many active connections, try to remove one. + Choose a random outgoing connection to a node + that has at least one other connection. + */ + int r = rand() % nc; + int i = 0; + + for list_each(connection_t, c, connection_list) { + if(!c->status.active || c->status.control) + continue; + + if(i++ != r) + continue; + + if(!c->outgoing || !c->node || c->node->edge_tree->count < 2) + break; - if(receive_meta(c) < 0) { + logger(DEBUG_CONNECTIONS, LOG_INFO, "Autodisconnecting from %s", c->name); + list_delete(outgoing_list, c->outgoing); + c->outgoing = NULL; terminate_connection(c, c->status.active); - continue; + break; + } + } + + if(nc >= autoconnect) { + /* If we have enough active connections, + remove any pending outgoing connections. + */ + for list_each(outgoing_t, o, outgoing_list) { + bool found = false; + for list_each(connection_t, c, connection_list) { + if(c->outgoing == o) { + found = true; + break; + } + } + if(!found) { + logger(DEBUG_CONNECTIONS, LOG_INFO, "Cancelled outgoing connection to %s", o->name); + list_delete_node(outgoing_list, node); + } } } } - for(i = 0; i < listen_sockets; i++) { - if(FD_ISSET(listen_socket[i].udp, f)) - handle_incoming_vpn_data(listen_socket[i].udp); + timeout_set(data, &(struct timeval){5, rand() % 100000}); +} - if(FD_ISSET(listen_socket[i].tcp, f)) - handle_new_meta_connection(listen_socket[i].tcp); +void handle_meta_connection_data(connection_t *c) { + if (!receive_meta(c)) { + terminate_connection(c, c->status.active); + return; } } -/* - this is where it all happens... -*/ -void main_loop(void) -{ - fd_set fset; - struct timeval tv; - int r; - time_t last_ping_check; - event_t *event; +#ifndef HAVE_MINGW +static void sigterm_handler(void *data) { + logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum)); + event_exit(); +} - cp(); +static void sighup_handler(void *data) { + logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum)); + reopenlogger(); + reload_configuration(); +} - last_ping_check = now; - srand(now); +static void sigalrm_handler(void *data) { + logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum)); + retry(); +} +#endif - for(;;) { - now = time(NULL); +int reload_configuration(void) { + char *fname = NULL; - tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ - tv.tv_usec = 0; + /* Reread our own configuration file */ - build_fdset(&fset); + exit_configuration(&config_tree); + init_configuration(&config_tree); - r = select(FD_SETSIZE, &fset, NULL, NULL, &tv); + if(!read_server_config()) { + logger(DEBUG_ALWAYS, LOG_ERR, "Unable to reread configuration file, exitting."); + event_exit(); + return EINVAL; + } - if(r < 0) { - if(errno != EINTR && errno != EAGAIN) { - syslog(LOG_ERR, _("Error while waiting for input: %s"), - strerror(errno)); - cp_trace(); - dump_connections(); - return; - } + read_config_options(config_tree, NULL); - continue; - } + xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, myself->name); + read_config_file(config_tree, fname); + free(fname); - check_network_activity(&fset); + /* Parse some options that are allowed to be changed while tinc is running */ - if(do_purge) { - purge(); - do_purge = 0; - } + setup_myself_reloadable(); - /* Let's check if everybody is still alive */ + /* If StrictSubnet is set, expire deleted Subnets and read new ones in */ - if(last_ping_check + pingtimeout < now) { - check_dead_connections(); - last_ping_check = now; + if(strictsubnets) { + for splay_each(subnet_t, subnet, subnet_tree) + subnet->expires = 1; - if(routing_mode == RMODE_SWITCH) - age_mac(); + load_all_subnets(); - age_past_requests(); + for splay_each(subnet_t, subnet, subnet_tree) { + if(subnet->expires == 1) { + send_del_subnet(everyone, subnet); + if(subnet->owner->status.reachable) + subnet_update(subnet->owner, subnet, false); + subnet_del(subnet->owner, subnet); + } else if(subnet->expires == -1) { + subnet->expires = 0; + } else { + send_add_subnet(everyone, subnet); + if(subnet->owner->status.reachable) + subnet_update(subnet->owner, subnet, true); + } + } + } else { /* Only read our own subnets back in */ + for splay_each(subnet_t, subnet, myself->subnet_tree) + if(!subnet->expires) + subnet->expires = 1; - /* Should we regenerate our key? */ + config_t *cfg = lookup_config(config_tree, "Subnet"); - if(keyexpires < now) { - if(debug_lvl >= DEBUG_STATUS) - syslog(LOG_INFO, _("Regenerating symmetric key")); + while(cfg) { + subnet_t *subnet, *s2; - RAND_pseudo_bytes(myself->key, myself->keylength); - send_key_changed(broadcast, myself); - keyexpires = now + keylifetime; - } - } + if(!get_config_subnet(cfg, &subnet)) + continue; + if((s2 = lookup_subnet(myself, subnet))) { + if(s2->expires == 1) + s2->expires = 0; - while((event = get_expired_event())) { - event->handler(event->data); - free(event); - } + free_subnet(subnet); + } else { + subnet_add(myself, subnet); + send_add_subnet(everyone, subnet); + subnet_update(myself, subnet, true); + } - if(sigalrm) { - syslog(LOG_INFO, _("Flushing event queue")); + cfg = lookup_config_next(config_tree, cfg); + } - while(event_tree->head) { - event = (event_t *) event_tree->head->data; - event->handler(event->data); - event_del(event); + for splay_each(subnet_t, subnet, myself->subnet_tree) { + if(subnet->expires == 1) { + send_del_subnet(everyone, subnet); + subnet_update(myself, subnet, false); + subnet_del(myself, subnet); } - sigalrm = 0; } + } - if(sighup) { - sighup = 0; - close_network_connections(); - exit_configuration(&config_tree); + /* Try to make outgoing connections */ - syslog(LOG_INFO, _("Rereading configuration file and restarting in 5 seconds...")); - sleep(5); + try_outgoing_connections(); - init_configuration(&config_tree); + /* Close connections to hosts that have a changed or deleted host config file */ - if(read_server_config()) { - syslog(LOG_ERR, - _("Unable to reread configuration file, exitting.")); - exit(1); - } + for list_each(connection_t, c, connection_list) { + if(c->status.control) + continue; - if(setup_network_connections()) - return; + xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, c->name); + struct stat s; + if(stat(fname, &s) || s.st_mtime > last_config_check) { + logger(DEBUG_CONNECTIONS, LOG_INFO, "Host config file of %s has been changed", c->name); + terminate_connection(c, c->status.active); + } + free(fname); + } - continue; + last_config_check = now.tv_sec; + + return 0; +} + +void retry(void) { + for list_each(connection_t, c, connection_list) { + if(c->outgoing && !c->node) { + timeout_del(&c->outgoing->ev); + if(c->status.connecting) + close(c->socket); + c->outgoing->timeout = 0; + terminate_connection(c, c->status.active); } } } + +/* + this is where it all happens... +*/ +int main_loop(void) { + timeout_t pingtimer = {{0}}; + timeout_t periodictimer = {{0}}; + + timeout_add(&pingtimer, timeout_handler, &pingtimer, &(struct timeval){pingtimeout, rand() % 100000}); + timeout_add(&periodictimer, periodic_handler, &periodictimer, &(struct timeval){pingtimeout, rand() % 100000}); + +#ifndef HAVE_MINGW + signal_t sighup = {0}; + signal_t sigterm = {0}; + signal_t sigquit = {0}; + signal_t sigint = {0}; + signal_t sigalrm = {0}; + + signal_add(&sighup, sighup_handler, &sighup, SIGHUP); + signal_add(&sigterm, sigterm_handler, &sigterm, SIGTERM); + signal_add(&sigquit, sigterm_handler, &sigquit, SIGQUIT); + signal_add(&sigint, sigterm_handler, &sigint, SIGINT); + signal_add(&sigalrm, sigalrm_handler, &sigalrm, SIGALRM); +#endif + + if(!event_loop()) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", strerror(errno)); + return 1; + } + +#ifndef HAVE_MINGW + signal_del(&sighup); + signal_del(&sigalrm); + signal_del(&sigquit); + signal_del(&sigterm); +#endif + + timeout_del(&periodictimer); + timeout_del(&pingtimer); + + return 0; +}