X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=37ae11667aff71b4db4cad058fbeb02a2de6b84e;hp=59dd39b30c327b8f15f5deb6360148a043deb466;hb=99763e34d52fcfe76b0bb9c7f3a17ace51cfdbfc;hpb=35af4051c3749cd2c2137a7eb57171a1fbb12af7 diff --git a/src/net.c b/src/net.c index 59dd39b3..37ae1166 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, - 2000-2009 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 @@ -42,8 +43,14 @@ bool do_purge = false; volatile bool running = false; +#ifdef HAVE_PSELECT +bool graph_dump = false; +#endif time_t now = 0; +int contradicting_add_edge = 0; +int contradicting_del_edge = 0; +static int sleeptime = 10; /* Purge edges and subnets of unreachable nodes. Use carefully. */ @@ -63,21 +70,26 @@ static void purge(void) { if(!n->status.reachable) { ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Purging node %s (%s)", n->name, - n->hostname); + 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); + 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; - if(!tunnelserver) - send_del_edge(broadcast, e); + + if(!tunnelserver) { + send_del_edge(everyone, e); + } + edge_del(e); } } @@ -94,12 +106,16 @@ static void purge(void) { enext = enode->next; e = enode->data; - if(e->to == n) + if(e->to == n) { break; + } } - if(!enode) + if(!enode && (!strictsubnets || !n->subnet_tree->head)) + /* in strictsubnets mode do not delete nodes with subnets */ + { node_del(n); + } } } } @@ -122,34 +138,64 @@ static int build_fdset(fd_set *readset, fd_set *writeset) { if(c->status.remove) { connection_del(c); - if(!connection_tree->head) + + if(!connection_tree->head) { purge(); + } } else { FD_SET(c->socket, readset); - if(c->outbuflen > 0) + + if(c->outbuflen > 0 || c->status.connecting) { FD_SET(c->socket, writeset); - if(c->socket > max) + } + + 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) + + if(listen_socket[i].tcp > max) { max = listen_socket[i].tcp; + } + FD_SET(listen_socket[i].udp, readset); - if(listen_socket[i].udp > max) + + if(listen_socket[i].udp > max) { max = listen_socket[i].udp; + } } - if(device_fd >= 0) + if(device_fd >= 0) { FD_SET(device_fd, readset); - if(device_fd > max) + } + + if(device_fd > max) { max = device_fd; - + } + return max; } +/* Put a misbehaving connection in the tarpit */ +void tarpit(int fd) { + static int pits[10] = {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1}; + static int next_pit = 0; + + if(pits[next_pit] != -1) { + closesocket(pits[next_pit]); + } + + pits[next_pit++] = fd; + + if(next_pit >= (int)(sizeof pits / sizeof pits[0])) { + next_pit = 0; + } +} + /* Terminate a connection: - Close the socket @@ -158,26 +204,41 @@ static int build_fdset(fd_set *readset, fd_set *writeset) { - Deactivate the host */ void terminate_connection(connection_t *c, bool report) { - if(c->status.remove) + if(c->status.remove) { return; + } ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)", - c->name, c->hostname); + c->name, c->hostname); c->status.remove = true; c->status.active = false; - if(c->node) + if(c->node) { c->node->connection = NULL; + } - if(c->socket) - closesocket(c->socket); + if(c->socket) { + if(c->status.tarpit) { + tarpit(c->socket); + } else { + closesocket(c->socket); + } + } if(c->edge) { - if(report && !tunnelserver) - send_del_edge(broadcast, c->edge); + if(!c->node) { + logger(LOG_ERR, "Connection to %s (%s) has an edge but node is NULL!", c->name, c->hostname); + // And that should never happen. + abort(); + } + + if(report && !tunnelserver) { + send_del_edge(everyone, c->edge); + } edge_del(c->edge); + c->edge = NULL; /* Run MST and SSSP algorithms */ @@ -188,26 +249,32 @@ void terminate_connection(connection_t *c, bool report) { if(report && !c->node->status.reachable) { edge_t *e; e = lookup_edge(c->node, myself); + if(e) { - if(!tunnelserver) - send_del_edge(broadcast, e); + if(!tunnelserver) { + send_del_edge(everyone, e); + } + edge_del(e); } } } + free_connection_partially(c); + /* Check if this was our outgoing connection */ if(c->outgoing) { - retry_outgoing(c->outgoing); - c->outgoing = NULL; + c->status.remove = false; + do_outgoing_connection(c); } - free(c->outbuf); - c->outbuf = NULL; - c->outbuflen = 0; - c->outbufsize = 0; - c->outbufstart = 0; +#ifndef HAVE_MINGW + /* Clean up dead proxy processes */ + + while(waitpid(-1, NULL, WNOHANG) > 0); + +#endif } /* @@ -226,40 +293,43 @@ static void check_dead_connections(void) { next = node->next; c = node->data; - if(c->last_ping_time + pingtimeout < now) { + 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); + c->name, c->hostname, (long)(now - c->last_ping_time)); c->status.timeout = true; terminate_connection(c, true); - } else if(c->last_ping_time + pinginterval < now) { + } else if(c->last_ping_time + pinginterval <= now) { 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)); + 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); + c->name, c->hostname); + if(c->status.connecting) { c->status.connecting = false; closesocket(c->socket); do_outgoing_connection(c); } else { + c->status.tarpit = true; terminate_connection(c, false); } } } - if(c->outbuflen > 0 && c->last_flushed_time + pingtimeout < now) { + 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); + "%s (%s) could not flush for %ld seconds (%d bytes remaining)", + c->name, c->hostname, (long)(now - c->last_flushed_time), c->outbuflen); c->status.timeout = true; terminate_connection(c, true); } @@ -271,18 +341,30 @@ static void check_dead_connections(void) { check all connections to see if anything happened on their sockets */ -static void check_network_activity(fd_set * readset, fd_set * writeset) { +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; + static int errors = 0; /* check input from kernel */ if(device_fd >= 0 && FD_ISSET(device_fd, readset)) { - if(read_packet(&packet)) { - packet.priority = 0; - route(myself, &packet); + if(devops.read(&packet)) { + if(packet.len) { + errors = 0; + packet.priority = 0; + route(myself, &packet); + } + } else { + usleep(errors * 50000); + errors++; + + if(errors > 10) { + logger(LOG_ERR, "Too many errors from %s, exiting!", device); + running = false; + } } } @@ -290,34 +372,36 @@ static void check_network_activity(fd_set * readset, fd_set * writeset) { for(node = connection_tree->head; node; node = node->next) { c = node->data; - if(c->status.remove) + if(c->status.remove) { continue; + } - if(FD_ISSET(c->socket, readset)) { + if(FD_ISSET(c->socket, writeset)) { if(c->status.connecting) { c->status.connecting = false; - getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len); + getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len); - if(!result) + if(!result) { finish_connecting(c); - else { + } else { ifdebug(CONNECTIONS) logger(LOG_DEBUG, - "Error while connecting to %s (%s): %s", - c->name, c->hostname, strerror(result)); + "Error while connecting to %s (%s): %s", + c->name, c->hostname, sockstrerror(result)); closesocket(c->socket); do_outgoing_connection(c); continue; } } - if(!receive_meta(c)) { + if(!flush_meta(c)) { terminate_connection(c, c->status.active); continue; } } - if(FD_ISSET(c->socket, writeset)) { - if(!flush_meta(c)) { + if(FD_ISSET(c->socket, readset)) { + if(!receive_meta(c)) { + c->status.tarpit = true; terminate_connection(c, c->status.active); continue; } @@ -325,11 +409,13 @@ static void check_network_activity(fd_set * readset, fd_set * writeset) { } for(i = 0; i < listen_sockets; i++) { - if(FD_ISSET(listen_socket[i].udp, readset)) - handle_incoming_vpn_data(listen_socket[i].udp); + if(FD_ISSET(listen_socket[i].udp, readset)) { + handle_incoming_vpn_data(i); + } - if(FD_ISSET(listen_socket[i].tcp, readset)) + if(FD_ISSET(listen_socket[i].tcp, readset)) { handle_new_meta_connection(listen_socket[i].tcp); + } } } @@ -338,7 +424,13 @@ static void check_network_activity(fd_set * readset, fd_set * writeset) { */ int main_loop(void) { fd_set readset, writeset; +#ifdef HAVE_PSELECT + struct timespec tv; + sigset_t omask, block_mask; + time_t next_event; +#else struct timeval tv; +#endif int r, maxfd; time_t last_ping_check, last_config_check, last_graph_dump; event_t *event; @@ -346,40 +438,74 @@ int main_loop(void) { last_ping_check = now; last_config_check = now; last_graph_dump = now; - + srand(now); +#ifdef HAVE_PSELECT + + if(lookup_config(config_tree, "GraphDumpFile")) { + graph_dump = true; + } + + /* Block SIGHUP & SIGALRM */ + sigemptyset(&block_mask); + sigaddset(&block_mask, SIGHUP); + sigaddset(&block_mask, SIGALRM); + sigprocmask(SIG_BLOCK, &block_mask, &omask); +#endif + running = true; while(running) { - now = time(NULL); +#ifdef HAVE_PSELECT + next_event = last_ping_check + pingtimeout; + + if(graph_dump && next_event > last_graph_dump + 60) { + next_event = last_graph_dump + 60; + } + + if((event = peek_next_event()) && next_event > event->time) { + next_event = event->time; + } + + if(next_event <= now) { + tv.tv_sec = 0; + } else { + tv.tv_sec = next_event - now; + } - // tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ + tv.tv_nsec = 0; +#else tv.tv_sec = 1; tv.tv_usec = 0; +#endif maxfd = build_fdset(&readset, &writeset); #ifdef HAVE_MINGW LeaveCriticalSection(&mutex); #endif +#ifdef HAVE_PSELECT + r = pselect(maxfd + 1, &readset, &writeset, NULL, &tv, &omask); +#else r = select(maxfd + 1, &readset, &writeset, NULL, &tv); +#endif + now = time(NULL); #ifdef HAVE_MINGW EnterCriticalSection(&mutex); #endif if(r < 0) { - if(errno != EINTR && errno != EAGAIN) { - logger(LOG_ERR, "Error while waiting for input: %s", - strerror(errno)); + if(!sockwouldblock(sockerrno)) { + logger(LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno)); dump_connections(); return 1; } - - continue; } - check_network_activity(&readset, &writeset); + if(r > 0) { + check_network_activity(&readset, &writeset); + } if(do_purge) { purge(); @@ -388,18 +514,19 @@ int main_loop(void) { /* Let's check if everybody is still alive */ - if(last_ping_check + pingtimeout < now) { + if(last_ping_check + pingtimeout <= now) { check_dead_connections(); last_ping_check = now; - if(routing_mode == RMODE_SWITCH) + if(routing_mode == RMODE_SWITCH) { age_subnets(); + } age_past_requests(); /* Should we regenerate our key? */ - if(keyexpires < now) { + if(keyexpires <= now) { avl_node_t *node; node_t *n; @@ -407,20 +534,55 @@ int main_loop(void) { for(node = node_tree->head; node; node = node->next) { n = node->data; + if(n->inkey) { free(n->inkey); n->inkey = NULL; } } - send_key_changed(broadcast, myself); + send_key_changed(); keyexpires = now + keylifetime; } + + /* Detect ADD_EDGE/DEL_EDGE storms that are caused when + * two tinc daemons with the same name are on the VPN. + * If so, sleep a while. If this happens multiple times + * in a row, sleep longer. */ + + if(contradicting_del_edge > 100 && contradicting_add_edge > 100) { + logger(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; + } + } + + contradicting_add_edge = 0; + contradicting_del_edge = 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; + + if(c->status.active) { + send_ping(c); + } + } + sigalrm = false; } @@ -434,9 +596,11 @@ int main_loop(void) { avl_node_t *node, *next; char *fname; struct stat s; - + sighup = false; - + + reopenlogger(); + /* Reread our own configuration file */ exit_configuration(&config_tree); @@ -466,37 +630,82 @@ int main_loop(void) { for(list_node_t *node = outgoing_list->head; node; node = node->next) { outgoing_t *outgoing = node->data; - if(outgoing->event) + if(outgoing->event) { event_del(outgoing->event); + } } 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) + + if(stat(fname, &s) || s.st_mtime > last_config_check) { terminate_connection(c, c->status.active); + } + free(fname); } last_config_check = now; + /* If StrictSubnet is set, expire deleted Subnets and read new ones in */ + + if(strictsubnets) { + subnet_t *subnet; + + for(node = subnet_tree->head; node; node = node->next) { + subnet = node->data; + subnet->expires = 1; + } + + load_all_subnets(); + + for(node = subnet_tree->head; node; node = next) { + next = node->next; + subnet = node->data; + + 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); + } + } + } + } + /* Try to make outgoing connections */ - + try_outgoing_connections(); } - + /* Dump graph if wanted every 60 seconds*/ - if(last_graph_dump + 60 < now) { + if(last_graph_dump + 60 <= now) { dump_graph(); last_graph_dump = now; } } +#ifdef HAVE_PSELECT + /* Restore SIGHUP & SIGALARM mask */ + sigprocmask(SIG_SETMASK, &omask, NULL); +#endif + return 0; }