X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=37ae11667aff71b4db4cad058fbeb02a2de6b84e;hp=0f354cd73b9b453a96331e0fc09c0e165bb1ba85;hb=99763e34d52fcfe76b0bb9c7f3a17ace51cfdbfc;hpb=0b9175e998c2180e5d73ef3d644a49d620c68cad diff --git a/src/net.c b/src/net.c index 0f354cd7..37ae1166 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, + 2000-2015 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 @@ -13,109 +15,107 @@ 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 1.35.4.188 2003/07/06 22:11:32 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 -#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 -#ifdef HAVE_NETINET_IN_SYSTM_H -#include -#endif -#include -#ifdef HAVE_NETINET_IP_H -#include -#endif -#ifdef HAVE_NETINET_TCP_H -#include -#endif +#include "system.h" #include -#include -#include -#include -#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 "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 "logger.h" - -#include "system.h" +#include "subnet.h" +#include "xalloc.h" -int do_purge = 0; -int sighup = 0; -int sigalrm = 0; +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. */ -void purge(void) -{ +static void purge(void) { avl_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"); - 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 = (node_t *) nnode->data; + n = nnode->data; if(!n->status.reachable) { - logger(DEBUG_SCARY_THINGS, LOG_DEBUG, _("Purging node %s (%s)"), n->name, - n->hostname); + 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 = (subnet_t *) snode->data; - send_del_subnet(broadcast, s); - subnet_del(n, s); + s = snode->data; + 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); + e = enode->data; + + if(!tunnelserver) { + send_del_edge(everyone, e); + } + edge_del(e); } + } + } + + /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */ - node_del(n); + 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 && (!strictsubnets || !n->subnet_tree->head)) + /* in strictsubnets mode do not delete nodes with subnets */ + { + node_del(n); + } } } } @@ -124,90 +124,157 @@ void purge(void) put all file descriptors in an fd_set array While we're at it, purge stuff that needs to be removed. */ -int build_fdset(fd_set * fs) -{ +static int build_fdset(fd_set *readset, fd_set *writeset) { avl_node_t *node, *next; connection_t *c; int i, max = 0; - cp(); - - FD_ZERO(fs); + FD_ZERO(readset); + FD_ZERO(writeset); for(node = connection_tree->head; node; node = next) { next = node->next; - c = (connection_t *) node->data; + c = node->data; if(c->status.remove) { connection_del(c); - if(!connection_tree->head) + + if(!connection_tree->head) { purge(); + } } else { - FD_SET(c->socket, fs); - if(c->socket > max) + FD_SET(c->socket, readset); + + if(c->outbuflen > 0 || c->status.connecting) { + 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, fs); - if(listen_socket[i].tcp > max) + FD_SET(listen_socket[i].tcp, readset); + + if(listen_socket[i].tcp > max) { max = listen_socket[i].tcp; - FD_SET(listen_socket[i].udp, fs); - if(listen_socket[i].udp > max) + } + + FD_SET(listen_socket[i].udp, readset); + + if(listen_socket[i].udp > max) { max = listen_socket[i].udp; + } } - FD_SET(device_fd, fs); - if(device_fd > max) + if(device_fd >= 0) { + FD_SET(device_fd, readset); + } + + 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 - - Remove associated edge and tell other connections about it if report = 1 + - 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, int report) -{ - cp(); - - if(c->status.remove) +void terminate_connection(connection_t *c, bool report) { + if(c->status.remove) { return; + } - logger(DEBUG_CONNECTIONS, LOG_NOTICE, _("Closing connection with %s (%s)"), - c->name, c->hostname); + ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)", + c->name, c->hostname); - c->status.remove = 1; - c->status.active = 0; + c->status.remove = true; + c->status.active = false; - if(c->node) + if(c->node) { c->node->connection = NULL; + } - if(c->socket) - close(c->socket); + if(c->socket) { + if(c->status.tarpit) { + tarpit(c->socket); + } else { + closesocket(c->socket); + } + } if(c->edge) { - if(report) - 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 */ 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); + } + } } + 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); } + +#ifndef HAVE_MINGW + /* Clean up dead proxy processes */ + + while(waitpid(-1, NULL, WNOHANG) > 0); + +#endif } /* @@ -218,37 +285,53 @@ 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) -{ +static 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; + 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) { - logger(DEBUG_CONNECTIONS, LOG_INFO, _("%s (%s) didn't respond to PING"), - c->name, c->hostname); - c->status.timeout = 1; - terminate_connection(c, 1); - } else { + ifdebug(CONNECTIONS) logger(LOG_INFO, "%s (%s) didn't respond to PING in %ld seconds", + 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) { send_ping(c); } } else { if(c->status.remove) { - logger(DEBUG_ALWAYS, LOG_WARNING, _("Old connection_t for %s (%s) status %04x still lingering, deleting..."), - c->name, c->hostname, c->status); + 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; } - logger(DEBUG_CONNECTIONS, LOG_WARNING, _("Timeout from %s (%s) during authentication"), - c->name, c->hostname); - terminate_connection(c, 0); + + 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 { + c->status.tarpit = true; + terminate_connection(c, false); + } + } + } + + 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, (long)(now - c->last_flushed_time), c->outbuflen); + c->status.timeout = true; + terminate_connection(c, true); } } } @@ -258,45 +341,67 @@ void check_dead_connections(void) check all connections to see if anything happened on their sockets */ -void check_network_activity(fd_set * f) -{ +static void check_network_activity(fd_set *readset, fd_set *writeset) { connection_t *c; avl_node_t *node; int result, i; - int len = sizeof(result); + 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(devops.read(&packet)) { + if(packet.len) { + errors = 0; + packet.priority = 0; + route(myself, &packet); + } + } else { + usleep(errors * 50000); + errors++; - cp(); - - if(FD_ISSET(device_fd, f)) { - if(!read_packet(&packet)) - route_outgoing(&packet); + if(errors > 10) { + logger(LOG_ERR, "Too many errors from %s, exiting!", device); + running = false; + } + } } + /* check meta connections */ for(node = connection_tree->head; node; node = node->next) { - c = (connection_t *) node->data; + c = node->data; - if(c->status.remove) + if(c->status.remove) { continue; + } - if(FD_ISSET(c->socket, f)) { + if(FD_ISSET(c->socket, writeset)) { if(c->status.connecting) { - c->status.connecting = 0; - getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len); + c->status.connecting = false; + getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len); - if(!result) + if(!result) { finish_connecting(c); - else { - logger(DEBUG_CONNECTIONS, LOG_DEBUG, - _("Error while connecting to %s (%s): %s"), - c->name, c->hostname, strerror(result)); - close(c->socket); + } 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); continue; } } - if(receive_meta(c) < 0) { + if(!flush_meta(c)) { + terminate_connection(c, c->status.active); + continue; + } + } + + if(FD_ISSET(c->socket, readset)) { + if(!receive_meta(c)) { + c->status.tarpit = true; terminate_connection(c, c->status.active); continue; } @@ -304,143 +409,303 @@ void check_network_activity(fd_set * f) } for(i = 0; i < listen_sockets; i++) { - if(FD_ISSET(listen_socket[i].udp, f)) - 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, f)) + if(FD_ISSET(listen_socket[i].tcp, readset)) { handle_new_meta_connection(listen_socket[i].tcp); + } } } /* this is where it all happens... */ -void main_loop(void) -{ - fd_set fset; +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; + time_t last_ping_check, last_config_check, last_graph_dump; event_t *event; - cp(); - last_ping_check = now; last_config_check = now; + last_graph_dump = now; + srand(now); - for(;;) { - now = time(NULL); +#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) { +#ifdef HAVE_PSELECT + next_event = last_ping_check + pingtimeout; + + if(graph_dump && next_event > last_graph_dump + 60) { + next_event = last_graph_dump + 60; + } - tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ + 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_nsec = 0; +#else + tv.tv_sec = 1; tv.tv_usec = 0; +#endif - maxfd = build_fdset(&fset); + maxfd = build_fdset(&readset, &writeset); - r = select(maxfd + 1, &fset, NULL, NULL, &tv); +#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(DEBUG_ALWAYS, LOG_ERR, _("Error while waiting for input: %s"), - strerror(errno)); - cp_trace(); + if(!sockwouldblock(sockerrno)) { + logger(LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno)); dump_connections(); - return; + return 1; } - - continue; } - check_network_activity(&fset); + if(r > 0) { + check_network_activity(&readset, &writeset); + } if(do_purge) { purge(); - do_purge = 0; + do_purge = false; } /* 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) - age_mac(); + if(routing_mode == RMODE_SWITCH) { + age_subnets(); + } age_past_requests(); /* Should we regenerate our key? */ - if(keyexpires < now) { - logger(DEBUG_STATUS, LOG_INFO, _("Regenerating symmetric key")); + if(keyexpires <= now) { + avl_node_t *node; + node_t *n; + + ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys"); + + for(node = node_tree->head; node; node = node->next) { + n = node->data; - RAND_pseudo_bytes(myself->key, myself->keylength); - EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, myself->key, myself->key + myself->cipher->key_len); - send_key_changed(broadcast, myself); + if(n->inkey) { + free(n->inkey); + n->inkey = NULL; + } + } + + 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. */ - while((event = get_expired_event())) { - event->handler(event->data); - free(event); + 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) { - logger(DEBUG_ALWAYS, LOG_INFO, _("Flushing event queue")); + 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; - while(event_tree->head) { - event = (event_t *) event_tree->head->data; - event->handler(event->data); - event_del(event); + if(c->status.active) { + send_ping(c); + } } - sigalrm = 0; + + sigalrm = false; + } + + while((event = get_expired_event())) { + event->handler(event->data); + free_event(event); } if(sighup) { connection_t *c; - avl_node_t *node; + avl_node_t *node, *next; char *fname; struct stat s; - - sighup = 0; - + + sighup = false; + + reopenlogger(); + /* Reread our own configuration file */ exit_configuration(&config_tree); init_configuration(&config_tree); - if(read_server_config()) { - logger(DEBUG_ALWAYS, LOG_ERR, _("Unable to reread configuration file, exitting.")); - exit(1); + if(!read_server_config()) { + logger(LOG_ERR, "Unable to reread configuration file, exitting."); + return 1; } + /* Cancel non-active outgoing connections */ + + for(node = connection_tree->head; node; node = next) { + next = node->next; + c = node->data; + + c->outgoing = NULL; + + if(c->status.connecting) { + terminate_connection(c, false); + connection_del(c); + } + } + + /* Wipe list of outgoing connections */ + + for(list_node_t *node = outgoing_list->head; node; node = node->next) { + outgoing_t *outgoing = node->data; + + 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 = (connection_t *) node->data; - - if(c->outgoing) { - free(c->outgoing->name); - 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) + 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); } 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(); - - continue; + } + + /* Dump graph if wanted every 60 seconds*/ + + 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; }