X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=8328db914d824e316de5c708a27baf30f4b10bb8;hp=6ffd9989d5d4356e6e83c1e3cc08edfa20e16b08;hb=b6b302cee9de92d157f73d7739cc259d269c0ca0;hpb=292354912f346fe467f557f0dc026b519997289c diff --git a/src/net.c b/src/net.c index 6ffd9989..8328db91 100644 --- a/src/net.c +++ b/src/net.c @@ -1,8 +1,9 @@ /* net.c -- most of the network code Copyright (C) 1998-2005 Ivo Timmermans, - 2000-2010 Guus Sliepen + 2000-2015 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 @@ -21,63 +22,47 @@ #include "system.h" -#include - #include "utils.h" -#include "avl_tree.h" #include "conf.h" #include "connection.h" #include "device.h" -#include "event.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 "route.h" #include "subnet.h" #include "xalloc.h" -bool do_purge = false; -volatile bool running = false; - -time_t now = 0; +int contradicting_add_edge = 0; +int contradicting_del_edge = 0; +static int sleeptime = 10; +time_t last_config_check = 0; +static timeout_t pingtimer; +static timeout_t periodictimer; /* Purge edges and subnets of unreachable nodes. Use carefully. */ -static void purge(void) { - avl_node_t *nnode, *nnext, *enode, *enext, *snode, *snext; - node_t *n; - edge_t *e; - subnet_t *s; - - ifdebug(PROTOCOL) logger(LOG_DEBUG, "Purging unreachable nodes"); +void purge(void) { + logger(DEBUG_PROTOCOL, 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; - + for splay_each(node_t, n, node_tree) { if(!n->status.reachable) { - ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Purging node %s (%s)", n->name, - n->hostname); + logger(DEBUG_SCARY_THINGS, 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; - send_del_subnet(broadcast, s); + 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 = enode->data; + for splay_each(edge_t, e, n->edge_tree) { if(!tunnelserver) - send_del_edge(broadcast, e); + send_del_edge(everyone, e); edge_del(e); } } @@ -85,100 +70,38 @@ static void purge(void) { /* 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; - + for splay_each(node_t, n, node_tree) { if(!n->status.reachable) { - for(enode = edge_weight_tree->head; enode; enode = enext) { - enext = enode->next; - e = enode->data; - + for splay_each(edge_t, e, edge_weight_tree) if(e->to == n) - break; - } + return; - if(!enode && (!strictsubnets || !n->subnet_tree->head)) + if(!autoconnect && (!strictsubnets || !n->subnet_tree->head)) /* in strictsubnets mode do not delete nodes with subnets */ node_del(n); } } } -/* - put all file descriptors in an fd_set array - While we're at it, purge stuff that needs to be removed. -*/ -static int build_fdset(fd_set *readset, fd_set *writeset) { - avl_node_t *node, *next; - connection_t *c; - int i, max = 0; - - FD_ZERO(readset); - FD_ZERO(writeset); - - for(node = connection_tree->head; node; node = next) { - next = node->next; - c = node->data; - - if(c->status.remove) { - connection_del(c); - if(!connection_tree->head) - purge(); - } else { - FD_SET(c->socket, readset); - if(c->outbuflen > 0) - FD_SET(c->socket, writeset); - if(c->socket > max) - max = c->socket; - } - } - - for(i = 0; i < listen_sockets; i++) { - FD_SET(listen_socket[i].tcp, readset); - if(listen_socket[i].tcp > max) - max = listen_socket[i].tcp; - FD_SET(listen_socket[i].udp, readset); - if(listen_socket[i].udp > max) - max = listen_socket[i].udp; - } - - if(device_fd >= 0) - FD_SET(device_fd, readset); - if(device_fd > max) - max = device_fd; - - return max; -} - /* Terminate a connection: - - Close the socket - - Remove associated edge and tell other connections about it if report = true + - 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, bool report) { - if(c->status.remove) - return; - - ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)", - c->name, c->hostname); + logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Closing connection with %s (%s)", c->name, c->hostname); - c->status.remove = true; - c->status.active = false; - - if(c->node) + if(c->node && c->node->connection == c) c->node->connection = NULL; - if(c->socket) - closesocket(c->socket); - if(c->edge) { if(report && !tunnelserver) - send_del_edge(broadcast, c->edge); + send_del_edge(everyone, c->edge); edge_del(c->edge); + c->edge = NULL; /* Run MST and SSSP algorithms */ @@ -191,24 +114,25 @@ void terminate_connection(connection_t *c, bool report) { e = lookup_edge(c->node, myself); if(e) { if(!tunnelserver) - send_del_edge(broadcast, e); + 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); + +#ifndef HAVE_MINGW + /* Clean up dead proxy processes */ - free(c->outbuf); - c->outbuf = NULL; - c->outbuflen = 0; - c->outbufsize = 0; - c->outbufstart = 0; + while(waitpid(-1, NULL, WNOHANG) > 0); +#endif } /* @@ -219,288 +143,339 @@ void terminate_connection(connection_t *c, bool report) { end does not reply in time, we consider them dead and close the connection. */ -static void check_dead_connections(void) { - avl_node_t *node, *next; - connection_t *c; - - for(node = connection_tree->head; node; node = next) { - next = node->next; - c = 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->status.active) { + if(c->last_ping_time + pingtimeout <= now.tv_sec) { + if(c->edge) { + try_tx(c->node, false); 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); - c->status.timeout = true; - terminate_connection(c, true); - } else if(c->last_ping_time + pinginterval < now) { + 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) { - logger(LOG_WARNING, "Old connection_t for %s (%s) status %04x still lingering, deleting...", - c->name, c->hostname, bitfield_to_int(&c->status, sizeof c->status)); - connection_del(c); continue; - } - ifdebug(CONNECTIONS) logger(LOG_WARNING, "Timeout from %s (%s) during authentication", - c->name, c->hostname); - if(c->status.connecting) { - c->status.connecting = false; - closesocket(c->socket); - do_outgoing_connection(c); } else { - terminate_connection(c, false); + continue; } + } 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->edge); } - if(c->outbuflen > 0 && c->last_flushed_time + pingtimeout < now) { - if(c->status.active) { - ifdebug(CONNECTIONS) logger(LOG_INFO, - "%s (%s) could not flush for %ld seconds (%d bytes remaining)", - c->name, c->hostname, now - c->last_flushed_time, c->outbuflen); - c->status.timeout = true; - terminate_connection(c, true); - } - } } + + timeout_set(data, &(struct timeval){1, rand() % 100000}); } -/* - check all connections to see if anything - happened on their sockets -*/ -static void check_network_activity(fd_set * readset, fd_set * writeset) { - connection_t *c; - avl_node_t *node; - int result, i; - socklen_t len = sizeof(result); - vpn_packet_t packet; - - /* check input from kernel */ - if(device_fd >= 0 && FD_ISSET(device_fd, readset)) { - if(read_packet(&packet)) { - packet.priority = 0; - route(myself, &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); + nanosleep(&(struct timespec){sleeptime, 0}, NULL); + sleeptime *= 2; + if(sleeptime < 0) + sleeptime = 3600; + } else { + sleeptime /= 2; + if(sleeptime < 10) + sleeptime = 10; } - /* check meta connections */ - for(node = connection_tree->head; node; node = node->next) { - c = 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->edge) + nc++; + } + + if(nc < 3) { + /* 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 - 1); + int i = 0; + + for splay_each(node_t, n, node_tree) { + if(n == myself) + continue; - if(FD_ISSET(c->socket, readset)) { - 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, sockstrerror(result)); - closesocket(c->socket); - do_outgoing_connection(c); + 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 > 3) { + /* 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->edge) + continue; - if(!receive_meta(c)) { - terminate_connection(c, c->status.active); - continue; + if(i++ != r) + continue; + + if(!c->outgoing || !c->node || c->node->edge_tree->count < 2) + break; + + logger(DEBUG_CONNECTIONS, LOG_INFO, "Autodisconnecting from %s", c->name); + list_delete(outgoing_list, c->outgoing); + c->outgoing = NULL; + terminate_connection(c, c->edge); + break; } } - if(FD_ISSET(c->socket, writeset)) { - if(!flush_meta(c)) { - terminate_connection(c, c->status.active); - continue; + if(nc >= 3) { + /* 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, readset)) - handle_incoming_vpn_data(listen_socket[i].udp); + timeout_set(data, &(struct timeval){5, rand() % 100000}); +} - if(FD_ISSET(listen_socket[i].tcp, readset)) - handle_new_meta_connection(listen_socket[i].tcp); +void handle_meta_connection_data(connection_t *c) { + if (!receive_meta(c)) { + terminate_connection(c, c->edge); + return; } } -/* - this is where it all happens... -*/ -int main_loop(void) { - fd_set readset, writeset; - struct timeval tv; - int r, maxfd; - time_t last_ping_check, last_config_check, last_graph_dump; - 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(); +} - last_ping_check = now; - last_config_check = now; - last_graph_dump = now; - - srand(now); +static void sighup_handler(void *data) { + logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum)); + reopenlogger(); + if(reload_configuration()) + exit(1); +} - running = true; +static void sigalrm_handler(void *data) { + logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum)); + retry(); +} +#endif - while(running) { - now = time(NULL); +int reload_configuration(void) { + char fname[PATH_MAX]; - // tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ - tv.tv_sec = 1; - tv.tv_usec = 0; + /* Reread our own configuration file */ - maxfd = build_fdset(&readset, &writeset); + exit_configuration(&config_tree); + init_configuration(&config_tree); -#ifdef HAVE_MINGW - LeaveCriticalSection(&mutex); -#endif - r = select(maxfd + 1, &readset, &writeset, NULL, &tv); -#ifdef HAVE_MINGW - EnterCriticalSection(&mutex); -#endif + if(!read_server_config()) { + logger(DEBUG_ALWAYS, LOG_ERR, "Unable to reread configuration file."); + return EINVAL; + } - if(r < 0) { - if(!sockwouldblock(sockerrno)) { - logger(LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno)); - dump_connections(); - return 1; - } - } + read_config_options(config_tree, NULL); - if(r > 0) - check_network_activity(&readset, &writeset); + snprintf(fname, sizeof fname, "%s" SLASH "hosts" SLASH "%s", confbase, myself->name); + read_config_file(config_tree, fname); - if(do_purge) { - purge(); - do_purge = false; - } + /* Parse some options that are allowed to be changed while tinc is running */ - /* Let's check if everybody is still alive */ + setup_myself_reloadable(); - if(last_ping_check + pingtimeout < now) { - check_dead_connections(); - last_ping_check = now; + /* If StrictSubnet is set, expire deleted Subnets and read new ones in */ - if(routing_mode == RMODE_SWITCH) - age_subnets(); + if(strictsubnets) { + for splay_each(subnet_t, subnet, subnet_tree) + if (subnet->owner) + subnet->expires = 1; - age_past_requests(); + load_all_subnets(); - /* Should we regenerate our key? */ + for splay_each(subnet_t, subnet, subnet_tree) { + if (!subnet->owner) + continue; + 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; - if(keyexpires < now) { - avl_node_t *node; - node_t *n; + config_t *cfg = lookup_config(config_tree, "Subnet"); - ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys"); + while(cfg) { + subnet_t *subnet, *s2; - for(node = node_tree->head; node; node = node->next) { - n = node->data; - if(n->inkey) { - free(n->inkey); - n->inkey = NULL; - } - } + if(!get_config_subnet(cfg, &subnet)) + continue; - send_key_changed(broadcast, myself); - keyexpires = now + keylifetime; - } - } + if((s2 = lookup_subnet(myself, subnet))) { + if(s2->expires == 1) + s2->expires = 0; - if(sigalrm) { - avl_node_t *node; - logger(LOG_INFO, "Flushing event queue"); - expire_events(); - for(node = connection_tree->head; node; node = node->next) { - connection_t *c = node->data; - send_ping(c); + free_subnet(subnet); + } else { + subnet_add(myself, subnet); + send_add_subnet(everyone, subnet); + subnet_update(myself, subnet, true); } - sigalrm = false; - } - while((event = get_expired_event())) { - event->handler(event->data); - free_event(event); + cfg = lookup_config_next(config_tree, cfg); } - if(sighup) { - connection_t *c; - avl_node_t *node, *next; - char *fname; - struct stat s; - - sighup = false; - - /* 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."); - return 1; + 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); } + } + } - /* Cancel non-active outgoing connections */ + /* Try to make outgoing connections */ - for(node = connection_tree->head; node; node = next) { - next = node->next; - c = node->data; + try_outgoing_connections(); - c->outgoing = NULL; + /* Close connections to hosts that have a changed or deleted host config file */ - if(c->status.connecting) { - terminate_connection(c, false); - connection_del(c); - } - } + for list_each(connection_t, c, connection_list) { + if(c->status.control) + continue; - /* Wipe list of outgoing connections */ + snprintf(fname, sizeof 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->edge); + } + } - for(list_node_t *node = outgoing_list->head; node; node = node->next) { - outgoing_t *outgoing = node->data; + last_config_check = now.tv_sec; - if(outgoing->event) - event_del(outgoing->event); - } + return 0; +} - list_delete_list(outgoing_list); - - /* Close connections to hosts that have a changed or deleted host config file */ - - for(node = connection_tree->head; node; node = node->next) { - c = node->data; - - xasprintf(&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); - } +void retry(void) { + /* Reset the reconnection timers for all outgoing connections */ + for list_each(outgoing_t, outgoing, outgoing_list) { + outgoing->timeout = 0; + if(outgoing->ev.cb) + timeout_set(&outgoing->ev, &(struct timeval){0, 0}); + } - last_config_check = now; + /* Check for outgoing connections that are in progress, and reset their ping timers */ + for list_each(connection_t, c, connection_list) { + if(c->outgoing && !c->node) + c->last_ping_time = 0; + } - /* Try to make outgoing connections */ - - try_outgoing_connections(); - } - - /* Dump graph if wanted every 60 seconds*/ + /* Kick the ping timeout handler */ + timeout_set(&pingtimer, &(struct timeval){0, 0}); +} - if(last_graph_dump + 60 < now) { - dump_graph(); - last_graph_dump = now; - } +/* + this is where it all happens... +*/ +int main_loop(void) { + timeout_add(&pingtimer, timeout_handler, &pingtimer, &(struct timeval){pingtimeout, rand() % 100000}); + timeout_add(&periodictimer, periodic_handler, &periodictimer, &(struct timeval){0, 0}); + +#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", sockstrerror(sockerrno)); + return 1; } +#ifndef HAVE_MINGW + signal_del(&sighup); + signal_del(&sigterm); + signal_del(&sigquit); + signal_del(&sigint); + signal_del(&sigalrm); +#endif + + timeout_del(&periodictimer); + timeout_del(&pingtimer); + return 0; }