X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet.c;h=7ebe37bf78792b6751727df4c70094553a36edff;hb=ce8775000ab38229a78ecf3dc26bab008ca0f332;hp=2efd34087c8883de855092be982b9d0dcda74d8a;hpb=950fb8e916b0e248dcaa72c96859acd6046683aa;p=tinc diff --git a/src/net.c b/src/net.c index 2efd3408..0fcc6fae 100644 --- a/src/net.c +++ b/src/net.c @@ -1,7 +1,8 @@ /* net.c -- most of the network code - Copyright (C) 1998,1999,2000 Ivo Timmermans , - 2000 Guus Sliepen + Copyright (C) 1998-2005 Ivo Timmermans, + 2000-2011 Guus Sliepen + 2006 Scott Lamb 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 @@ -13,1168 +14,368 @@ 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 1.35.4.33 2000/10/11 10:35:16 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 -#include -#include - -#include -#include +#include "system.h" +#include "utils.h" +#include "splay_tree.h" #include "conf.h" -#include "encr.h" +#include "connection.h" +#include "device.h" +#include "graph.h" +#include "logger.h" +#include "meta.h" #include "net.h" #include "netutl.h" +#include "process.h" #include "protocol.h" -#include "meta.h" - -#include "system.h" +#include "subnet.h" +#include "xalloc.h" + +int contradicting_add_edge = 0; +int contradicting_del_edge = 0; + +/* Purge edges and subnets of unreachable nodes. Use carefully. */ + +void purge(void) { + splay_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(broadcast, 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); + edge_del(e); + } + } + } -int tap_fd = -1; + /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */ -int total_tap_in = 0; -int total_tap_out = 0; -int total_socket_in = 0; -int total_socket_out = 0; + for(nnode = node_tree->head; nnode; nnode = nnext) { + nnext = nnode->next; + n = nnode->data; -int upstreamindex = 0; -static int seconds_till_retry; + if(!n->status.reachable) { + for(enode = edge_weight_tree->head; enode; enode = enext) { + enext = enode->next; + e = enode->data; -/* The global list of existing connections */ -conn_list_t *conn_list = NULL; -conn_list_t *myself = NULL; + if(e->to == n) + break; + } -/* - strip off the MAC adresses of an ethernet frame -*/ -void strip_mac_addresses(vpn_packet_t *p) -{ -cp - memmove(p->data, p->data + 12, p->len -= 12); -cp + if(!enode && (!strictsubnets || !n->subnet_tree->head)) + /* in strictsubnets mode do not delete nodes with subnets */ + node_del(n); + } + } } /* - reassemble MAC addresses + Terminate a connection: + - Close the socket + - 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 add_mac_addresses(vpn_packet_t *p) -{ -cp - memcpy(p->data + 12, p->data, p->len); - p->len += 12; - p->data[0] = p->data[6] = 0xfe; - p->data[1] = p->data[7] = 0xfd; - /* Really evil pointer stuff just below! */ - *((ip_t*)(&p->data[2])) = (ip_t)(htonl(myself->real_ip)); - *((ip_t*)(&p->data[8])) = *((ip_t*)(&p->data[26])); -cp -} +void terminate_connection(connection_t *c, bool report) { + ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Closing connection with %s (%s)", + c->name, c->hostname); -int xsend(conn_list_t *cl, vpn_packet_t *inpkt) -{ - vpn_packet_t outpkt; - int outlen, outpad; -cp - outpkt.len = inpkt->len; - EVP_EncryptInit(cl->cipher_pktctx, cl->cipher_pkttype, cl->cipher_pktkey, cl->cipher_pktiv); - EVP_EncryptUpdate(cl->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); - EVP_EncryptFinal(cl->cipher_pktctx, outpkt.data + outlen, &outpad); - outlen += outpad; - - if(debug_lvl > 3) - syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), - outlen, cl->name, cl->hostname); - - total_socket_out += outlen; - - cl->want_ping = 1; - - if((send(cl->socket, (char *) &(outpkt.len), outlen + 2, 0)) < 0) - { - syslog(LOG_ERR, _("Error sending packet to %s (%s): %m"), - cl->name, cl->hostname); - return -1; - } -cp - return 0; -} + c->status.active = false; -int xrecv(vpn_packet_t *inpkt) -{ - vpn_packet_t outpkt; - int outlen, outpad; -cp - if(debug_lvl > 3) - syslog(LOG_ERR, _("Receiving packet of %d bytes"), - inpkt->len); - - outpkt.len = inpkt->len; - EVP_DecryptInit(myself->cipher_pktctx, myself->cipher_pkttype, myself->cipher_pktkey, myself->cipher_pktiv); - EVP_DecryptUpdate(myself->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); - /* FIXME: grok DecryptFinal - EVP_DecryptFinal(myself->cipher_pktctx, outpkt.data + outlen, &outpad); - */ - - add_mac_addresses(&outpkt); - - if(write(tap_fd, outpkt.data, outpkt.len) < 0) - syslog(LOG_ERR, _("Can't write to tap device: %m")); - else - total_tap_out += outpkt.len; -cp - return 0; -} + if(c->node) + c->node->connection = NULL; -/* - add the given packet of size s to the - queue q, be it the send or receive queue -*/ -void add_queue(packet_queue_t **q, void *packet, size_t s) -{ - queue_element_t *e; -cp - e = xmalloc(sizeof(*e)); - e->packet = xmalloc(s); - memcpy(e->packet, packet, s); - - if(!*q) - { - *q = xmalloc(sizeof(**q)); - (*q)->head = (*q)->tail = NULL; - } - - e->next = NULL; /* We insert at the tail */ - - if((*q)->tail) /* Do we have a tail? */ - { - (*q)->tail->next = e; - e->prev = (*q)->tail; - } - else /* No tail -> no head too */ - { - (*q)->head = e; - e->prev = NULL; - } - - (*q)->tail = e; -cp -} + if(c->socket) + closesocket(c->socket); -/* Remove a queue element */ -void del_queue(packet_queue_t **q, queue_element_t *e) -{ -cp - free(e->packet); - - if(e->next) /* There is a successor, so we are not tail */ - { - if(e->prev) /* There is a predecessor, so we are not head */ - { - e->next->prev = e->prev; - e->prev->next = e->next; - } - else /* We are head */ - { - e->next->prev = NULL; - (*q)->head = e->next; - } - } - else /* We are tail (or all alone!) */ - { - if(e->prev) /* We are not alone :) */ - { - e->prev->next = NULL; - (*q)->tail = e->prev; - } - else /* Adieu */ - { - free(*q); - *q = NULL; - } - } - - free(e); -cp -} + if(c->edge) { + if(report && !tunnelserver) + send_del_edge(broadcast, c->edge); -/* - flush a queue by calling function for - each packet, and removing it when that - returned a zero exit code -*/ -void flush_queue(conn_list_t *cl, packet_queue_t **pq, - int (*function)(conn_list_t*,void*)) -{ - queue_element_t *p, *next = NULL; -cp - for(p = (*pq)->head; p != NULL; ) - { - next = p->next; - - if(!function(cl, p->packet)) - del_queue(pq, p); - - p = next; - } - - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Queue flushed")); -cp -} + edge_del(c->edge); -/* - flush the send&recv queues - void because nothing goes wrong here, packets - remain in the queue if something goes wrong -*/ -void flush_queues(conn_list_t *cl) -{ -cp - if(cl->sq) - { - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Flushing send queue for %s (%s)"), - cl->name, cl->hostname); - flush_queue(cl, &(cl->sq), xsend); - } - - if(cl->rq) - { - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Flushing receive queue for %s (%s)"), - cl->name, cl->hostname); - flush_queue(cl, &(cl->rq), xrecv); - } -cp -} + /* Run MST and SSSP algorithms */ -/* - send a packet to the given vpn ip. -*/ -int send_packet(ip_t to, vpn_packet_t *packet) -{ - conn_list_t *cl; -cp - if((cl = lookup_conn(to)) == NULL) - { - if(debug_lvl > 3) - { - syslog(LOG_NOTICE, _("Trying to look up %d.%d.%d.%d in connection list failed!"), - IP_ADDR_V(to)); - } - - return -1; - } - - /* If we ourselves have indirectdata flag set, we should send only to our uplink! */ - - /* The next few lines will be obsoleted, if we are going indirect, matching subnet_t - should point to only our uplink as the recepient - */ - - if(myself->flags & EXPORTINDIRECTDATA) - { - for(cl = conn_list; cl != NULL && !cl->status.outgoing; cl = cl->next); - if(!cl) - { /* No open outgoing connection has been found. */ - if(debug_lvl > 3) - syslog(LOG_NOTICE, _("There is no remote host I can send this packet to!")); - return -1; - } - } - else - - /* If indirectdata flag is set for the destination we just looked up, - * then real_ip is actually the vpn_ip of the gateway tincd - * it is behind. - */ - - if(cl->flags & INDIRECTDATA) - { - if(debug_lvl > 3) - syslog(LOG_NOTICE, _("Indirect packet to %s via %s"), - cl->name, cl->hostname); - if((cl = lookup_conn(cl->real_ip)) == NULL) - { - if(debug_lvl > 3) - syslog(LOG_NOTICE, _("Indirect look up %d.%d.%d.%d in connection list failed!"), IP_ADDR_V(to)); - - /* Gateway tincd dead? Should we kill it? (GS) */ - - return -1; - } - if(cl->flags & INDIRECTDATA) /* This should not happen */ - { - if(debug_lvl > 3) - syslog(LOG_NOTICE, _("Double indirection for %d.%d.%d.%d"), IP_ADDR_V(to)); - return -1; - } - } - - if(my_key_expiry <= time(NULL)) - regenerate_keys(); - - if(!cl->status.dataopen) - if(setup_vpn_connection(cl) < 0) - { - syslog(LOG_ERR, _("Could not open UDP connection to %s (%s)"), - cl->name, cl->hostname); - return -1; - } - - if(!cl->status.validkey) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"), - cl->name, cl->hostname); - add_queue(&(cl->sq), packet, packet->len + 2); - if(!cl->status.waitingforkey) - send_req_key(myself, cl); /* Keys should be sent to the host running the tincd */ - return 0; - } - - if(!cl->status.active) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("%s (%s) is not ready, queueing packet"), - cl->name, cl->hostname); - add_queue(&(cl->sq), packet, packet->len + 2); - return 0; /* We don't want to mess up, do we? */ - } - - /* can we send it? can we? can we? huh? */ -cp - return xsend(cl, packet); -} + graph(); -/* - open the local ethertap device -*/ -int setup_tap_fd(void) -{ - int nfd; - const char *tapfname; - config_t const *cfg; -cp - if((cfg = get_config_val(tapdevice)) == NULL) - tapfname = "/dev/tap0"; - else - tapfname = cfg->data.ptr; - - if((nfd = open(tapfname, O_RDWR | O_NONBLOCK)) < 0) - { - syslog(LOG_ERR, _("Could not open %s: %m"), tapfname); - return -1; - } - - tap_fd = nfd; -cp - return 0; -} + /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */ -/* - set up the socket that we listen on for incoming - (tcp) connections -*/ -int setup_listen_meta_socket(int port) -{ - int nfd, flags; - struct sockaddr_in a; - const int one = 1; - config_t const *cfg; -cp - if((nfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) - { - syslog(LOG_ERR, _("Creating metasocket failed: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl: %m")); - return -1; - } - - if((cfg = get_config_val(interface))) - { - if(setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, cfg->data.ptr, strlen(cfg->data.ptr))) - { - syslog(LOG_ERR, _("Unable to bind listen socket to interface %s: %m"), cfg->data.ptr); - return -1; - } - } - - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - - if((cfg = get_config_val(interfaceip))) - a.sin_addr.s_addr = htonl(cfg->data.ip->ip); - else - a.sin_addr.s_addr = htonl(INADDR_ANY); - - if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr))) - { - syslog(LOG_ERR, _("Can't bind to port %hd/tcp: %m"), port); - return -1; - } - - if(listen(nfd, 3)) - { - syslog(LOG_ERR, _("listen: %m")); - return -1; - } -cp - return nfd; -} + if(report && !c->node->status.reachable) { + edge_t *e; + e = lookup_edge(c->node, myself); + if(e) { + if(!tunnelserver) + send_del_edge(broadcast, e); + edge_del(e); + } + } + } -/* - setup the socket for incoming encrypted - data (the udp part) -*/ -int setup_vpn_in_socket(int port) -{ - int nfd, flags; - struct sockaddr_in a; - const int one = 1; -cp - if((nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) - { - syslog(LOG_ERR, _("Creating socket failed: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl: %m")); - return -1; - } - - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - a.sin_addr.s_addr = htonl(INADDR_ANY); - - if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr))) - { - syslog(LOG_ERR, _("Can't bind to port %hd/udp: %m"), port); - return -1; - } -cp - return nfd; -} + /* Check if this was our outgoing connection */ -/* - setup an outgoing meta (tcp) socket -*/ -int setup_outgoing_meta_socket(conn_list_t *cl) -{ - int flags; - struct sockaddr_in a; - config_t const *cfg; -cp - if(debug_lvl > 0) - syslog(LOG_INFO, _("Trying to connect to %s"), cl->hostname); - - if((cfg = get_config_val(upstreamport)) == NULL) - cl->port = 655; - else - cl->port = cfg->data.val; - - cl->meta_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); - if(cl->meta_socket == -1) - { - syslog(LOG_ERR, _("Creating socket for %s port %d failed: %m"), - cl->hostname, cl->port); - return -1; - } - - a.sin_family = AF_INET; - a.sin_port = htons(cl->port); - a.sin_addr.s_addr = htonl(cl->real_ip); - - if(connect(cl->meta_socket, (struct sockaddr *)&a, sizeof(a)) == -1) - { - syslog(LOG_ERR, _("%s port %hd: %m"), cl->hostname, cl->port); - return -1; - } - - flags = fcntl(cl->meta_socket, F_GETFL); - if(fcntl(cl->meta_socket, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl for %s port %d: %m"), - cl->hostname, cl->port); - return -1; - } - - if(debug_lvl > 0) - syslog(LOG_INFO, _("Connected to %s port %hd"), - cl->hostname, cl->port); -cp - return 0; -} + if(c->outgoing) + retry_outgoing(c->outgoing); -/* - setup an outgoing connection. It's not - necessary to also open an udp socket as - well, because the other host will initiate - an authentication sequence during which - we will do just that. -*/ -int setup_outgoing_connection(char *hostname) -{ - conn_list_t *ncn; - struct hostent *h; -cp - if(!(h = gethostbyname(hostname))) - { - syslog(LOG_ERR, _("Error looking up `%s': %m"), hostname); - return -1; - } - - ncn = new_conn_list(); - ncn->real_ip = ntohl(*((ip_t*)(h->h_addr_list[0]))); - ncn->hostname = hostlookup(htonl(ncn->real_ip)); - - if(setup_outgoing_meta_socket(ncn) < 0) - { - syslog(LOG_ERR, _("Could not set up a meta connection to %s"), - ncn->hostname); - free_conn_element(ncn); - return -1; - } - - ncn->status.meta = 1; - ncn->status.outgoing = 1; - ncn->next = conn_list; - conn_list = ncn; -cp - return 0; + connection_del(c); } /* - set up the local sockets (listen only) + Check if the other end is active. + If we have sent packets, but didn't receive any, + then possibly the other end is dead. We send a + PING request over the meta connection. If the other + end does not reply in time, we consider them dead + and close the connection. */ -int setup_myself(void) -{ - config_t const *cfg; -cp - myself = new_conn_list(); - - myself->hostname = "MYSELF"; /* FIXME? */ - myself->flags = 0; - - if(!(cfg = get_config_val(tincname))) /* Not acceptable */ - { - syslog(LOG_ERR, _("Name for tinc daemon required!")); - return -1; - } - else - myself->name = (char*)cfg->data.val; - - if(!(cfg = get_config_val(listenport))) - myself->port = 655; - else - myself->port = cfg->data.val; - - if((cfg = get_config_val(indirectdata))) - if(cfg->data.val == stupid_true) - myself->flags |= EXPORTINDIRECTDATA; - - if((cfg = get_config_val(tcponly))) - if(cfg->data.val == stupid_true) - myself->flags |= TCPONLY; - - if((myself->meta_socket = setup_listen_meta_socket(myself->port)) < 0) - { - syslog(LOG_ERR, _("Unable to set up a listening socket")); - return -1; - } - - if((myself->socket = setup_vpn_in_socket(myself->port)) < 0) - { - syslog(LOG_ERR, _("Unable to set up an incoming vpn data socket")); - close(myself->meta_socket); - return -1; - } - - myself->status.active = 1; - - syslog(LOG_NOTICE, _("Ready: listening on port %hd"), myself->port); -cp - return 0; -} +static void timeout_handler(int fd, short events, void *event) { + splay_node_t *node, *next; + connection_t *c; + time_t now = time(NULL); + + 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); + terminate_connection(c, true); + continue; + } else if(c->last_ping_time + pinginterval < now) { + send_ping(c); + } + } else { + if(c->status.connecting) { + ifdebug(CONNECTIONS) + logger(LOG_WARNING, "Timeout while connecting to %s (%s)", c->name, c->hostname); + c->status.connecting = false; + closesocket(c->socket); + do_outgoing_connection(c); + } else { + ifdebug(CONNECTIONS) logger(LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname); + terminate_connection(c, false); + continue; + } + } + } + } -RETSIGTYPE -sigalrm_handler(int a) -{ - config_t const *cfg; -cp - cfg = get_next_config_val(upstreamip, upstreamindex++); - - while(cfg) - { - if(!setup_outgoing_connection(cfg->data.ptr)) /* function returns 0 when there are no problems */ - { - signal(SIGALRM, SIG_IGN); - return; - } - cfg = get_next_config_val(upstreamip, upstreamindex++); /* Or else we try the next ConnectTo line */ - } - - signal(SIGALRM, sigalrm_handler); - upstreamindex = 0; - seconds_till_retry += 5; - if(seconds_till_retry > MAXTIMEOUT) /* Don't wait more than MAXTIMEOUT seconds. */ - seconds_till_retry = MAXTIMEOUT; - syslog(LOG_ERR, _("Still failed to connect to other, will retry in %d seconds"), - seconds_till_retry); - alarm(seconds_till_retry); -cp -} + if(contradicting_del_edge && contradicting_add_edge) { + logger(LOG_WARNING, "Possible node with same Name as us!"); -/* - setup all initial network connections -*/ -int setup_network_connections(void) -{ - config_t const *cfg; -cp - if((cfg = get_config_val(pingtimeout)) == NULL) - timeout = 5; - else - timeout = cfg->data.val; - - if(setup_tap_fd() < 0) - return -1; - - if(setup_myself() < 0) - return -1; - - if((cfg = get_next_config_val(upstreamip, upstreamindex++)) == NULL) - /* No upstream IP given, we're listen only. */ - return 0; - - while(cfg) - { - if(!setup_outgoing_connection(cfg->data.ptr)) /* function returns 0 when there are no problems */ - return 0; - cfg = get_next_config_val(upstreamip, upstreamindex++); /* Or else we try the next ConnectTo line */ - } - - signal(SIGALRM, sigalrm_handler); - upstreamindex = 0; - seconds_till_retry = MAXTIMEOUT; - syslog(LOG_NOTICE, _("Trying to re-establish outgoing connection in %d seconds"), seconds_till_retry); - alarm(seconds_till_retry); -cp - return 0; -} + if(rand() % 3 == 0) { + logger(LOG_ERR, "Shutting down, check configuration of all nodes for duplicate Names!"); + event_loopexit(NULL); + return; + } -/* - close all open network connections -*/ -void close_network_connections(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.dataopen) - { - shutdown(p->socket, 0); /* No more receptions */ - close(p->socket); + contradicting_add_edge = 0; + contradicting_del_edge = 0; } - if(p->status.meta) - { - send_termreq(p); - shutdown(p->meta_socket, 0); /* No more receptions */ - close(p->meta_socket); - } - } - - if(myself) - if(myself->status.active) - { - close(myself->meta_socket); - close(myself->socket); - } - - close(tap_fd); - destroy_conn_list(); - - syslog(LOG_NOTICE, _("Terminating")); -cp - return; -} -/* - create a data (udp) socket -*/ -int setup_vpn_connection(conn_list_t *cl) -{ - int nfd, flags; - struct sockaddr_in a; -cp - if(debug_lvl > 0) - syslog(LOG_DEBUG, _("Opening UDP socket to %s"), cl->hostname); - - nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); - if(nfd == -1) - { - syslog(LOG_ERR, _("Creating UDP socket failed: %m")); - return -1; - } - - a.sin_family = AF_INET; - a.sin_port = htons(cl->port); - a.sin_addr.s_addr = htonl(cl->real_ip); - - if(connect(nfd, (struct sockaddr *)&a, sizeof(a)) == -1) - { - syslog(LOG_ERR, _("Connecting to %s port %d failed: %m"), - cl->hostname, cl->port); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m %s (%s)"), __FILE__, __LINE__, nfd, - cl->name, cl->hostname); - return -1; - } - - cl->socket = nfd; - cl->status.dataopen = 1; -cp - return 0; + event_add(event, &(struct timeval){pingtimeout, 0}); } -/* - handle an incoming tcp connect call and open - a connection to it. -*/ -conn_list_t *create_new_connection(int sfd) -{ - conn_list_t *p; - struct sockaddr_in ci; - int len = sizeof(ci); -cp - p = new_conn_list(); - - if(getpeername(sfd, &ci, &len) < 0) - { - syslog(LOG_ERR, _("Error: getpeername: %m")); - return NULL; - } - - p->real_ip = ntohl(ci.sin_addr.s_addr); - p->hostname = hostlookup(ci.sin_addr.s_addr); - p->meta_socket = sfd; - p->status.meta = 1; - p->buflen = 0; - p->last_ping_time = time(NULL); - p->want_ping = 0; - - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Connection from %s port %d"), - p->hostname, htons(ci.sin_port)); - - if(send_basic_info(p) < 0) - { - free_conn_element(p); - return NULL; - } -cp - return p; -} +void handle_meta_connection_data(int fd, short events, void *data) { + connection_t *c = data; + int result; + socklen_t len = sizeof result; + + 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); + return; + } + } -/* - put all file descriptors in an fd_set array -*/ -void build_fdset(fd_set *fs) -{ - conn_list_t *p; -cp - FD_ZERO(fs); - - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.meta) - FD_SET(p->meta_socket, fs); - if(p->status.dataopen) - FD_SET(p->socket, fs); - } - - FD_SET(myself->meta_socket, fs); - FD_SET(myself->socket, fs); - FD_SET(tap_fd, fs); -cp + if (!receive_meta(c)) { + terminate_connection(c, c->status.active); + return; + } } -/* - receive incoming data from the listening - udp socket and write it to the ethertap - device after being decrypted -*/ -int handle_incoming_vpn_data() -{ - vpn_packet_t pkt; - int lenin; - int x, l = sizeof(x); -cp - if(getsockopt(myself->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m"), - __FILE__, __LINE__, myself->socket); - return -1; - } - if(x) - { - syslog(LOG_ERR, _("Incoming data socket error: %s"), strerror(x)); - return -1; - } - - if(recvfrom(myself->socket, (char *) &(pkt.len), MTU, 0, NULL, NULL) <= 0) - { - syslog(LOG_ERR, _("Receiving packet failed: %m")); - return -1; - } - -cp - return xrecv(&pkt); +static void sigterm_handler(int signal, short events, void *data) { + logger(LOG_NOTICE, "Got %s signal", strsignal(signal)); + event_loopexit(NULL); } -/* - terminate a connection and notify the other - end before closing the sockets -*/ -void terminate_connection(conn_list_t *cl) -{ - conn_list_t *p; - -cp - if(cl->status.remove) - return; - - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Closing connection with %s (%s)"), - cl->name, cl->hostname); - - if(cl->status.timeout) - send_timeout(cl); -/* else if(!cl->status.termreq) - send_termreq(cl); - */ - - if(cl->socket) - close(cl->socket); - if(cl->status.meta) - close(cl->meta_socket); - - cl->status.remove = 1; - - /* If this cl isn't active, don't send any DEL_HOSTs. */ - if(cl->status.active) - notify_others(cl,NULL,send_del_host); - -cp - /* Find all connections that were lost because they were behind cl - (the connection that was dropped). */ - if(cl->status.meta) - for(p = conn_list; p != NULL; p = p->next) - { - if((p->nexthop == cl) && (p != cl)) - { - if(cl->status.active && p->status.active) - notify_others(p,cl,send_del_host); - if(cl->socket) - close(cl->socket); - p->status.active = 0; - p->status.remove = 1; - } - } - - cl->status.active = 0; - - if(cl->status.outgoing) - { - signal(SIGALRM, sigalrm_handler); - seconds_till_retry = 5; - alarm(seconds_till_retry); - syslog(LOG_NOTICE, _("Trying to re-establish outgoing connection in 5 seconds")); - } -cp +static void sighup_handler(int signal, short events, void *data) { + logger(LOG_NOTICE, "Got %s signal", strsignal(signal)); + reload_configuration(); } -/* - Check if the other end is active. - If we have sent packets, but didn't receive any, - then possibly the other end is dead. We send a - PING request over the meta connection. If the other - end does not reply in time, we consider them dead - and close the connection. -*/ -int check_dead_connections(void) -{ - conn_list_t *p; - time_t now; -cp - now = time(NULL); - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - if(p->status.active && p->status.meta) - { - if(p->last_ping_time + timeout < now) - { - if(p->status.pinged && !p->status.got_pong) - { - if(debug_lvl > 1) - syslog(LOG_INFO, _("%s (%s) didn't respond to PING"), - p->name, p->hostname); - p->status.timeout = 1; - terminate_connection(p); - } - else if(p->want_ping) - { - send_ping(p); - p->last_ping_time = now; - p->status.pinged = 1; - p->status.got_pong = 0; - } - } +int reload_configuration(void) { + connection_t *c; + splay_node_t *node, *next; + char *fname; + struct stat s; + static time_t last_config_check = 0; + + /* 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."); + event_loopexit(NULL); + return EINVAL; } - } -cp - return 0; -} -/* - accept a new tcp connect and create a - new connection -*/ -int handle_new_meta_connection() -{ - conn_list_t *ncn; - struct sockaddr client; - int nfd, len = sizeof(client); -cp - if((nfd = accept(myself->meta_socket, &client, &len)) < 0) - { - syslog(LOG_ERR, _("Accepting a new connection failed: %m")); - return -1; - } - - if(!(ncn = create_new_connection(nfd))) - { - shutdown(nfd, 2); - close(nfd); - syslog(LOG_NOTICE, _("Closed attempted connection")); - return 0; - } - - ncn->status.meta = 1; - ncn->next = conn_list; - conn_list = ncn; -cp - return 0; -} + /* Close connections to hosts that have a changed or deleted host config file */ + + for(node = connection_tree->head; node; node = next) { + c = node->data; + next = node->next; + + if(c->outgoing) { + free(c->outgoing->name); + if(c->outgoing->ai) + freeaddrinfo(c->outgoing->ai); + free(c->outgoing); + c->outgoing = NULL; + } + + 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); + } -/* - check all connections to see if anything - happened on their sockets -*/ -void check_network_activity(fd_set *f) -{ - conn_list_t *p; - int x, l = sizeof(x); -cp - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - - if(p->status.dataopen) - if(FD_ISSET(p->socket, f)) - { - /* - The only thing that can happen to get us here is apparently an - error on this outgoing(!) UDP socket that isn't immediate (i.e. - something that will not trigger an error directly on send()). - I've once got here when it said `No route to host'. - */ - getsockopt(p->socket, SOL_SOCKET, SO_ERROR, &x, &l); - syslog(LOG_ERR, _("Outgoing data socket error for %s (%s): %s"), - p->name, p->hostname, strerror(x)); - terminate_connection(p); - return; - } - - if(p->status.meta) - if(FD_ISSET(p->meta_socket, f)) - if(receive_meta(p) < 0) - { - terminate_connection(p); - return; - } - } - - if(FD_ISSET(myself->socket, f)) - handle_incoming_vpn_data(); - - if(FD_ISSET(myself->meta_socket, f)) - handle_new_meta_connection(); -cp + last_config_check = time(NULL); + + /* 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(broadcast, 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(broadcast, subnet); + if(subnet->owner->status.reachable) + subnet_update(subnet->owner, subnet, true); + } + } + } + + /* Try to make outgoing connections */ + + try_outgoing_connections(); + + return 0; } -/* - read, encrypt and send data that is - available through the ethertap device -*/ -void handle_tap_input(void) -{ - vpn_packet_t vp; - ip_t from, to; - int ether_type, lenin; -cp - memset(&vp, 0, sizeof(vp)); - if((lenin = read(tap_fd, &vp, MTU)) <= 0) - { - syslog(LOG_ERR, _("Error while reading from tapdevice: %m")); - return; - } - - total_tap_in += lenin; - - ether_type = ntohs(*((unsigned short*)(&vp.data[12]))); - if(ether_type != 0x0800) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("Non-IP ethernet frame %04x from %02x:%02x:%02x:%02x:%02x:%02x"), ether_type, MAC_ADDR_V(vp.data[6])); - return; - } - - if(lenin < 32) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("Dropping short packet from %02x:%02x:%02x:%02x:%02x:%02x"), MAC_ADDR_V(vp.data[6])); - return; - } - - from = ntohl(*((unsigned long*)(&vp.data[26]))); - to = ntohl(*((unsigned long*)(&vp.data[30]))); - - vp.len = (length_t)lenin - 2; - - strip_mac_addresses(&vp); - - send_packet(to, &vp); -cp +void retry(void) { + connection_t *c; + splay_node_t *node; + + for(node = connection_tree->head; node; node = node->next) { + c = node->data; + + if(c->outgoing && !c->node) { + if(timeout_initialized(&c->outgoing->ev)) + event_del(&c->outgoing->ev); + if(c->status.connecting) + close(c->socket); + c->outgoing->timeout = 0; + do_outgoing_connection(c); + } + } } /* this is where it all happens... */ -void main_loop(void) -{ - fd_set fset; - struct timeval tv; - int r; - time_t last_ping_check; -cp - last_ping_check = time(NULL); - - for(;;) - { - tv.tv_sec = timeout; - tv.tv_usec = 0; - - prune_conn_list(); - build_fdset(&fset); - - if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0) - { - if(errno != EINTR) /* because of alarm */ - { - syslog(LOG_ERR, _("Error while waiting for input: %m")); - return; - } - } - - if(sighup) - { - sighup = 0; - if(debug_lvl > 1) - syslog(LOG_INFO, _("Rereading configuration file")); - close_network_connections(); - clear_config(); - if(read_config_file(configfilename)) - { - syslog(LOG_ERR, _("Unable to reread configuration file, exiting")); - exit(0); - } - sleep(5); - setup_network_connections(); - continue; - } - - if(last_ping_check + timeout < time(NULL)) - /* Let's check if everybody is still alive */ - { - check_dead_connections(); - last_ping_check = time(NULL); +int main_loop(void) { + struct event timeout_event; + struct event sighup_event; + struct event sigterm_event; + struct event sigquit_event; + + timeout_set(&timeout_event, timeout_handler, &timeout_event); + event_add(&timeout_event, &(struct timeval){pingtimeout, 0}); + +#ifdef SIGHUP + signal_set(&sighup_event, SIGHUP, sighup_handler, NULL); + signal_add(&sighup_event, NULL); +#endif +#ifdef SIGTERM + signal_set(&sigterm_event, SIGTERM, sigterm_handler, NULL); + signal_add(&sigterm_event, NULL); +#endif +#ifdef SIGQUIT + signal_set(&sigquit_event, SIGQUIT, sigterm_handler, NULL); + signal_add(&sigquit_event, NULL); +#endif + + if(event_loop(0) < 0) { + logger(LOG_ERR, "Error while waiting for input: %s", strerror(errno)); + return 1; } - if(r > 0) - { - check_network_activity(&fset); + signal_del(&sighup_event); + signal_del(&sigterm_event); + signal_del(&sigquit_event); + event_del(&timeout_event); - /* local tap data */ - if(FD_ISSET(tap_fd, &fset)) - handle_tap_input(); - } - } -cp + return 0; }