X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=0496a864e4dd4c028a07ab7bf4f52c353471c02e;hp=69a0133e652bcd399a63bf3d8e594d417559772e;hb=80e15d8b96e5313b33c91003b1f75d7f6db9924e;hpb=5638b9830f9cfe43f545c37cfd7ccf1d4b4bfcc6 diff --git a/src/net.c b/src/net.c index 69a0133e..0496a864 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, + 2000-2012 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 @@ -13,203 +15,203 @@ 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 1.35.4.178 2002/09/06 21:22:35 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 "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 "system.h" +#include "subnet.h" +#include "xalloc.h" -#ifndef HAVE_RAND_PSEUDO_BYTES -#define RAND_pseudo_bytes RAND_bytes +bool do_purge = false; +volatile bool running = false; +#ifdef HAVE_PSELECT +bool graph_dump = false; #endif -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; /* 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 - 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; - - 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); - } - - for(enode = n->edge_tree->head; enode; enode = enext) - { - enext = enode->next; - e = (edge_t *)enode->data; - send_del_edge(broadcast, e); - edge_del(e); - } - - node_del(n); - } - } -cp +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"); + + /* 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; + 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(everyone, 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 && (!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. */ -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); - } - - for(i = 0; i < listen_sockets; i++) - { - FD_SET(listen_socket[i].tcp, fs); - FD_SET(listen_socket[i].udp, fs); - } - - FD_SET(device_fd, fs); -cp +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 = 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) - return; +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); + + c->status.remove = true; + c->status.active = false; + + if(c->node) + c->node->connection = NULL; - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Closing connection with %s (%s)"), - c->name, c->hostname); + if(c->socket) + closesocket(c->socket); - c->status.remove = 1; - c->status.active = 0; + if(c->edge) { + if(report && !tunnelserver) + send_del_edge(everyone, c->edge); - if(c->node) - c->node->connection = NULL; + edge_del(c->edge); - if(c->socket) - close(c->socket); + /* Run MST and SSSP algorithms */ - if(c->edge) - { - if(report) - send_del_edge(broadcast, c->edge); + graph(); - edge_del(c->edge); + /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */ - /* Run MST and SSSP algorithms */ + 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); + } + } + } - graph(); - } + free_connection_partially(c); - /* Check if this was our outgoing connection */ + /* Check if this was our outgoing connection */ - if(c->outgoing) - { - retry_outgoing(c->outgoing); - c->outgoing = NULL; - } -cp + if(c->outgoing) { + c->status.remove = false; + do_outgoing_connection(c); + } } /* @@ -220,222 +222,387 @@ cp 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; - if(c->last_ping_time + pingtimeout < now) - { - 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 - { - 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; - } - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_WARNING, _("Timeout from %s (%s) during authentication"), - c->name, c->hostname); - terminate_connection(c, 0); - } - } - } -cp +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; + + 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->status.timeout = true; + terminate_connection(c, true); + } 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)); + 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); + } + } + } + + 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); + } + } + } } /* 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); - } - - for(node = connection_tree->head; node; node = node->next) - { - c = (connection_t *)node->data; - - if(c->status.remove) - continue; - - 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); - continue; - } - } - if(receive_meta(c) < 0) - { - terminate_connection(c, c->status.active); - continue; - } - } - } - - 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].tcp, f)) - handle_new_meta_connection(listen_socket[i].tcp); - } -cp +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(devops.read(&packet)) { + 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; + } + } + } + + /* check meta connections */ + for(node = connection_tree->head; node; node = node->next) { + c = node->data; + + if(c->status.remove) + continue; + + if(FD_ISSET(c->socket, readset)) { + if(c->status.connecting) { + c->status.connecting = false; + getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&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); + continue; + } + } + + if(!receive_meta(c)) { + terminate_connection(c, c->status.active); + continue; + } + } + + if(FD_ISSET(c->socket, writeset)) { + if(!flush_meta(c)) { + terminate_connection(c, c->status.active); + continue; + } + } + } + + for(i = 0; i < listen_sockets; i++) { + if(FD_ISSET(listen_socket[i].udp, readset)) + handle_incoming_vpn_data(i); + + 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; - struct timeval tv; - int r; - time_t last_ping_check; - event_t *event; -cp - last_ping_check = now; - - srand(now); - - for(;;) - { - now = time(NULL); - - tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ - tv.tv_usec = 0; - - build_fdset(&fset); - - if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0) - { - if(errno != EINTR && errno != EAGAIN) - { - syslog(LOG_ERR, _("Error while waiting for input: %s"), strerror(errno)); - cp_trace(); - dump_connections(); - return; - } - - continue; - } - - check_network_activity(&fset); - - if(do_purge) - { - purge(); - do_purge = 0; - } - - /* Let's check if everybody is still alive */ - - if(last_ping_check + pingtimeout < now) - { - check_dead_connections(); - last_ping_check = now; - - if(routing_mode== RMODE_SWITCH) - age_mac(); - - age_past_requests(); - - /* Should we regenerate our key? */ - - if(keyexpires < now) - { - if(debug_lvl >= DEBUG_STATUS) - syslog(LOG_INFO, _("Regenerating symmetric key")); - - RAND_pseudo_bytes(myself->key, myself->keylength); - send_key_changed(broadcast, myself); - keyexpires = now + keylifetime; - } - } - - - while((event = get_expired_event())) - { - event->handler(event->data); - free(event); - } - - if(sigalrm) - { - syslog(LOG_INFO, _("Flushing event queue")); - - while(event_tree->head) - { - event = (event_t *)event_tree->head->data; - event->handler(event->data); - event_del(event); - } - sigalrm = 0; - } - - if(sighup) - { - sighup = 0; - close_network_connections(); - exit_configuration(&config_tree); - - syslog(LOG_INFO, _("Rereading configuration file and restarting in 5 seconds...")); - sleep(5); - - init_configuration(&config_tree); - - if(read_server_config()) - { - syslog(LOG_ERR, _("Unable to reread configuration file, exitting.")); - exit(1); - } - - if(setup_network_connections()) - return; - - continue; - } - } -cp +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; + + 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) { +#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_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(!sockwouldblock(sockerrno)) { + logger(LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno)); + dump_connections(); + return 1; + } + } + + if(r > 0) + check_network_activity(&readset, &writeset); + + if(do_purge) { + purge(); + do_purge = false; + } + + /* Let's check if everybody is still alive */ + + if(last_ping_check + pingtimeout <= now) { + check_dead_connections(); + last_ping_check = now; + + if(routing_mode == RMODE_SWITCH) + age_subnets(); + + age_past_requests(); + + /* Should we regenerate our 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; + 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. */ + + 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; + send_ping(c); + } + sigalrm = false; + } + + while((event = get_expired_event())) { + event->handler(event->data); + free_event(event); + } + + if(sighup) { + connection_t *c; + avl_node_t *node, *next; + char *fname; + struct stat s; + + sighup = false; + + reopenlogger(); + + /* 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; + } + + /* 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 = 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(); + } + + /* 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; }