X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=62dce9bd1c6f3359c0ef704707ec0f059e3e353d;hp=a5989c36d50eafb4b2cf8d59c3e460d8b11849a4;hb=9fa27097dd82e20299f5277ecb4efffb4a99669c;hpb=c04c84c98055c6b9e9e7890d3992648a3b715a1a diff --git a/src/net.c b/src/net.c index a5989c36..e2e2833c 100644 --- a/src/net.c +++ b/src/net.c @@ -1,7 +1,7 @@ /* net.c -- most of the network code - Copyright (C) 1998,1999,2000 Ivo Timmermans , - 2000 Guus Sliepen + Copyright (C) 1998-2005 Ivo Timmermans, + 2000-2006 Guus Sliepen 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 @@ -17,954 +17,206 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: net.c,v 1.35.4.28 2000/09/14 11:54:50 guus Exp $ + $Id$ */ -#include "config.h" - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include -#include +#include "system.h" + +#include +#include "utils.h" +#include "avl_tree.h" #include "conf.h" -#include "encr.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 "route.h" +#include "subnet.h" +#include "xalloc.h" -#include "system.h" - -int tap_fd = -1; +bool do_purge = false; +volatile bool running = false; -int total_tap_in = 0; -int total_tap_out = 0; -int total_socket_in = 0; -int total_socket_out = 0; +time_t now = 0; -int upstreamindex = 0; -static int seconds_till_retry; - -/* The global list of existing connections */ -conn_list_t *conn_list = NULL; -conn_list_t *myself = NULL; - -/* - strip off the MAC adresses of an ethernet frame -*/ -void strip_mac_addresses(vpn_packet_t *p) -{ - unsigned char tmp[MAXSIZE]; -cp - memcpy(tmp, p->data, p->len); - p->len -= 12; - memcpy(p->data, &tmp[12], p->len); -cp -} +/* Purge edges and subnets of unreachable nodes. Use carefully. */ -/* - reassemble MAC addresses -*/ -void add_mac_addresses(vpn_packet_t *p) +static void purge(void) { - unsigned char tmp[MAXSIZE]; -cp - memcpy(&tmp[12], p->data, p->len); - p->len += 12; - tmp[0] = tmp[6] = 0xfe; - tmp[1] = tmp[7] = 0xfd; - *((ip_t*)(&tmp[2])) = (ip_t)(htonl(myself->vpn_ip)); - *((ip_t*)(&tmp[8])) = *((ip_t*)(&tmp[26])); - memcpy(p->data, &tmp[0], p->len); -cp -} + 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")); + + /* 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; + if(!tunnelserver) + send_del_subnet(broadcast, s); + 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 xsend(conn_list_t *cl, void *packet) -{ - real_packet_t rp; -cp - do_encrypt((vpn_packet_t*)packet, &rp, cl->key); - rp.from = htonl(myself->vpn_ip); - rp.data.len = htons(rp.data.len); - rp.len = htons(rp.len); - - if(debug_lvl > 3) - syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), ntohs(rp.len), cl->id, cl->hostname); - - total_socket_out += ntohs(rp.len); - - cl->want_ping = 1; - - if((cl->flags | myself->flags) & TCPONLY) - return send_tcppacket(cl, (void*)&rp, ntohs(rp.len)); - - if((send(cl->socket, (char*)&rp, ntohs(rp.len), 0)) < 0) - { - syslog(LOG_ERR, _("Error sending packet to %s (%s): %m"), cl->id, cl->hostname); - return -1; - } -cp - return 0; -} + /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */ -int xrecv(conn_list_t *cl, void *packet) -{ - vpn_packet_t vp; - int lenin; -cp - do_decrypt((real_packet_t*)packet, &vp, cl->key); - add_mac_addresses(&vp); - - if(debug_lvl > 3) - syslog(LOG_ERR, _("Receiving packet of %d bytes from %s (%s)"), ((real_packet_t*)packet)->len, cl->id, cl->hostname); - - if((lenin = write(tap_fd, &vp, vp.len + sizeof(vp.len))) < 0) - syslog(LOG_ERR, _("Can't write to tap device: %m")); - else - total_tap_out += lenin; - - cl->want_ping = 0; - cl->last_ping_time = time(NULL); -cp - return 0; -} + for(nnode = node_tree->head; nnode; nnode = nnext) { + nnext = nnode->next; + n = nnode->data; -/* - 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(!n->status.reachable) { + for(enode = edge_weight_tree->head; enode; enode = enext) { + enext = enode->next; + e = enode->data; -/* 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(e->to == n) + break; + } -/* - 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 + if(!enode) + node_del(n); + } + } } /* - flush the send&recv queues - void because nothing goes wrong here, packets - remain in the queue if something goes wrong + put all file descriptors in an fd_set array + While we're at it, purge stuff that needs to be removed. */ -void flush_queues(conn_list_t *cl) +static int build_fdset(fd_set *readset, fd_set *writeset) { -cp - if(cl->sq) - { - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Flushing send queue for %s (%s)"), cl->id, 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->id, cl->hostname); - flush_queue(cl, &(cl->rq), xrecv); - } -cp -} + avl_node_t *node, *next; + connection_t *c; + int i, max = 0; + + cp(); + + 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; + } + } -/* - 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->id, 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->id, cl->hostname); - return -1; - } - - if(!cl->status.validkey) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("%s (%s) has no valid key, queueing packet"), cl->id, cl->hostname); - add_queue(&(cl->sq), packet, packet->len + 2); - if(!cl->status.waitingforkey) - send_key_request(cl->vpn_ip); /* 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->id, 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); -} + 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; + } -/* - 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; + FD_SET(device_fd, readset); + if(device_fd > max) + max = device_fd; + + return max; } /* - set up the socket that we listen on for incoming - (tcp) connections + 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 */ -int setup_listen_meta_socket(int port) +void terminate_connection(connection_t *c, bool report) { - 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; -} + cp(); -/* - 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; -} + if(c->status.remove) + return; -/* - 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; -} + ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Closing connection with %s (%s)"), + c->name, c->hostname); -/* - 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; -} + c->status.remove = true; + c->status.active = false; -/* - set up the local sockets (listen only) -*/ -int setup_myself(void) -{ - config_t const *cfg; -cp - myself = new_conn_list(); - - if(!(cfg = get_config_val(myvpnip))) - { - syslog(LOG_ERR, _("No value for my VPN IP given")); - return -1; - } - - myself->vpn_ip = cfg->data.ip->ip; - myself->vpn_hostname = hostlookup(htonl(myself->vpn_ip)); - myself->hostname = hostlookup(htonl(myself->vpn_ip)); - myself->vpn_mask = cfg->data.ip->mask; - myself->flags = 0; - - 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; -} + if(c->node) + c->node->connection = NULL; -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(c->socket) + closesocket(c->socket); -/* - 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(c->edge) { + if(report && !tunnelserver) + send_del_edge(broadcast, c->edge); -/* - 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); - } - 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; -} + edge_del(c->edge); -/* - 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->id, cl->hostname); - return -1; - } - - cl->socket = nfd; - cl->status.dataopen = 1; -cp - return 0; -} + /* Run MST and SSSP algorithms */ -/* - 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; -} + graph(); -/* - 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 the node is not reachable anymore but we remember it had an edge to us, clean it up */ -/* - receive incoming data from the listening - udp socket and write it to the ethertap - device after being decrypted -*/ -int handle_incoming_vpn_data(conn_list_t *cl) -{ - real_packet_t rp; - int lenin; - int x, l = sizeof(x); - conn_list_t *f; -cp - if(getsockopt(cl->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m %s (%s)"), __FILE__, __LINE__, cl->socket, cl->id, cl->hostname); - return -1; - } - if(x) - { - syslog(LOG_ERR, _("Incoming data socket error for %s (%s): %s"), cl->id, cl->hostname, strerror(x)); - return -1; - } - - rp.len = -1; - lenin = recvfrom(cl->socket, &rp, MTU, 0, NULL, NULL); - if(lenin <= 0) - { - syslog(LOG_ERR, _("Receiving packet from %s (%s) failed: %m"), cl->id, cl->hostname); - return -1; - } - total_socket_in += lenin; - - rp.data.len = ntohs(rp.data.len); - rp.len = ntohs(rp.len); - rp.from = ntohl(rp.from); - - if(rp.len >= 0) - { - f = lookup_conn(rp.from); - if(!f) - { - syslog(LOG_ERR, _("Got packet from %s (%s) with unknown origin %d.%d.%d.%d?"), cl->id, cl->hostname, IP_ADDR_V(rp.from)); - return -1; + 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); + } + } } - if(f->status.validkey) - xrecv(f, &rp); - else - { - add_queue(&(f->rq), &rp, rp.len); - if(!cl->status.waitingforkey) - send_key_request(rp.from); + /* Check if this was our outgoing connection */ + + if(c->outgoing) { + retry_outgoing(c->outgoing); + c->outgoing = NULL; } - if(my_key_expiry <= time(NULL)) - regenerate_keys(); - } -cp - return 0; -} - -/* - 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->id, 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 + free(c->outbuf); + c->outbuf = NULL; + c->outbuflen = 0; + c->outbufsize = 0; + c->outbufstart = 0; } /* @@ -975,330 +227,258 @@ cp end does not reply in time, we consider them dead and close the connection. */ -int check_dead_connections(void) +static void 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"), cl->id, cl->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; - } - } + avl_node_t *node, *next; + connection_t *c; + + cp(); + + 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, c->status.value); + 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); + } + } } - } -cp - return 0; -} - -/* - accept a new tcp connect and create a - new connection -*/ -int handle_new_meta_connection(conn_list_t *cl) -{ - conn_list_t *ncn; - struct sockaddr client; - int nfd, len = sizeof(client); -cp - if((nfd = accept(cl->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; -} - -/* - dispatch any incoming meta requests -*/ -int handle_incoming_meta_data(conn_list_t *cl) -{ - int x, l = sizeof(x); - int request, oldlen, i; - int lenin = 0; -cp - if(getsockopt(cl->meta_socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m %s (%s)"), __FILE__, __LINE__, cl->meta_socket, cl->id, cl->hostname); - return -1; - } - if(x) - { - syslog(LOG_ERR, _("Metadata socket error for %s (%s): %s"), cl->id, cl->hostname, strerror(x)); - return -1; - } - - lenin = read(cl->meta_socket, cl->buffer+cl->buflen, MAXBUFSIZE - cl->buflen); - - if(lenin<=0) - { - if(errno==EINTR) - return 0; - if(errno==0) - { - if(debug_lvl>DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Connection closed by %s (%s)"), cl->id, cl->hostname); - } - else - syslog(LOG_ERR, _("Metadata socket read error for %s (%s): %m"), cl->id, cl->hostname); - return -1; - } - - if(cl->status.encrypted) - { - /* FIXME: do decryption. */ - } - - oldlen = cl->buflen; - cl->buflen += lenin; - - for(;;) - { - cl->reqlen = 0; - - for(i = oldlen; i < cl->buflen; i++) - { - if(cl->buffer[i] == '\n') - { - cl->buffer[i] = 0; /* replace end-of-line by end-of-string so we can use sscanf */ - cl->reqlen = i + 1; - break; - } - } - - if(cl->reqlen) - { - if(debug_lvl > DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Got request from %s (%s): %s"), cl->id, cl->hostname, cl->buffer); - if(sscanf(cl->buffer, "%d", &request) == 1) - { - if((request < 0) || (request > 255) || (request_handlers[request] == NULL)) - { - syslog(LOG_ERR, _("Unknown request from %s (%s)"), cl->id, cl->hostname); - return -1; - } - else - { - if(debug_lvl > DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Got %s from %s (%s)"), request_name[request], cl->id, cl->hostname); - - if(request_handlers[request](cl)) /* Something went wrong. Probably scriptkiddies. Terminate. */ - { - syslog(LOG_ERR, _("Error while processing %s from %s (%s)"), request_name[request], cl->id, cl->hostname); - return -1; - } - } - else - { - syslog(LOG_ERR, _("Bogus data received from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - cl->buflen -= cl->reqlen; - memmove(cl->buffer, cl->buffer + cl->reqlen, cl->buflen); - oldlen = 0; - } - else - { - break; - } - } - - if(cl->buflen >= MAXBUFSIZE) - { - syslog(LOG_ERR, _("Metadata read buffer overflow for %s (%s)"), cl->id, cl->hostname); - return -1; - } - - cl->last_ping_time = time(NULL); - cl->want_ping = 0; -cp - return 0; } /* 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) { - 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"), cl->id, cl->hostname, strerror(x)); - terminate_connection(p); - return; - } - - if(p->status.meta) - if(FD_ISSET(p->meta_socket, f)) - if(handle_incoming_meta_data(p) < 0) - { - terminate_connection(p); - return; - } - } - - if(FD_ISSET(myself->socket, f)) - handle_incoming_vpn_data(myself); - - if(FD_ISSET(myself->meta_socket, f)) - handle_new_meta_connection(myself); -cp -} + connection_t *c; + avl_node_t *node; + int result, i; + socklen_t len = sizeof(result); + vpn_packet_t packet; + + cp(); + + /* check input from kernel */ + if(FD_ISSET(device_fd, readset)) { + if(read_packet(&packet)) + route(myself, &packet); + } -/* - 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 + /* 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, &result, &len); + + if(!result) + finish_connecting(c); + else { + ifdebug(CONNECTIONS) logger(LOG_DEBUG, + _("Error while connecting to %s (%s): %s"), + c->name, c->hostname, strerror(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(listen_socket[i].udp); + + 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) +int 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; - 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); - } + fd_set readset, writeset; + struct timeval tv; + int r, maxfd; + time_t last_ping_check, last_config_check; + event_t *event; - if(r > 0) - { - check_network_activity(&fset); + cp(); + + last_ping_check = now; + last_config_check = now; + srand(now); + + running = true; + + while(running) { + now = time(NULL); + + // tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ + tv.tv_sec = 1; + tv.tv_usec = 0; + + maxfd = build_fdset(&readset, &writeset); + + r = select(maxfd + 1, &readset, &writeset, NULL, &tv); + + if(r < 0) { + if(errno != EINTR && errno != EAGAIN) { + logger(LOG_ERR, _("Error while waiting for input: %s"), + strerror(errno)); + cp_trace(); + dump_connections(); + return 1; + } + + continue; + } + + 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) { + ifdebug(STATUS) logger(LOG_INFO, _("Regenerating symmetric key")); + + RAND_pseudo_bytes((unsigned char *)myself->key, myself->keylength); + if(myself->cipher) + EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, (unsigned char *)myself->key, (unsigned char *)myself->key + myself->cipher->key_len); + send_key_changed(broadcast, myself); + keyexpires = now + keylifetime; + } + } + + + while((event = get_expired_event())) { + event->handler(event->data); + free(event); + } + + if(sigalrm) { + logger(LOG_INFO, _("Flushing event queue")); + + while(event_tree->head) { + event = event_tree->head->data; + event->handler(event->data); + event_del(event); + } + sigalrm = false; + } + + if(sighup) { + connection_t *c; + avl_node_t *node; + 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; + } + + /* 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; + + 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) + terminate_connection(c, c->status.active); + free(fname); + } + + last_config_check = now; + + /* Try to make outgoing connections */ + + try_outgoing_connections(); + } + } - /* local tap data */ - if(FD_ISSET(tap_fd, &fset)) - handle_tap_input(); - } - } -cp + return 0; }