X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=67a949096f37a6ff8ea2b25ef3d55c26dfc91d4b;hp=246d62ca44ce31e30a5d417c20f0c7bd27649583;hb=04d33be4bd102de67bb6dba5c449e12fea0db4d2;hpb=ca73b722cbad5a08ec9bb5026ed5129da9a24bd8 diff --git a/src/net.c b/src/net.c index 246d62ca..67a94909 100644 --- a/src/net.c +++ b/src/net.c @@ -1,6 +1,7 @@ /* net.c -- most of the network code - Copyright (C) 1998,99 Ivo Timmermans + Copyright (C) 1998-2002 Ivo Timmermans , + 2000-2002 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 @@ -15,1087 +16,436 @@ 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 1.39 2002/04/28 12:46:26 zarq Exp $ */ #include "config.h" -#include #include #include #include #include +#ifdef HAVE_LINUX + #include + #include +#endif #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 + +#include -#include #include #include +#include +#include #include "conf.h" -#include "encr.h" +#include "connection.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 "logging.h" -int tap_fd = -1; - -int total_tap_in = 0; -int total_tap_out = 0; -int total_socket_in = 0; -int total_socket_out = 0; - -time_t last_ping_time = 0; - -/* 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 -} - -/* - reassemble MAC addresses -*/ -void add_mac_addresses(vpn_packet_t *p) -{ - 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 -} - -int xsend(conn_list_t *cl, void *packet) -{ - int r; - real_packet_t rp; -cp - do_encrypt((vpn_packet_t*)packet, &rp, cl->key); - rp.from = myself->vpn_ip; +#include "system.h" - if(debug_lvl > 3) - syslog(LOG_ERR, "Sent %d bytes to %lx", rp.len, cl->vpn_ip); +int do_purge = 0; +int sighup = 0; +int sigalrm = 0; - if((r = send(cl->socket, (char*)&rp, rp.len, 0)) < 0) - { - syslog(LOG_ERR, "Error sending data: %m"); - return -1; - } +time_t now = 0; - total_socket_out += r; -cp - return 0; -} +/* Purge edges and subnets of unreachable nodes. Use carefully. */ -int xrecv(conn_list_t *cl, void *packet) +void purge(void) { - vpn_packet_t vp; - int lenin; + avl_node_t *nnode, *nnext, *enode, *enext, *snode, *snext, *cnode; + node_t *n; + edge_t *e; + subnet_t *s; + connection_t *c; cp - do_decrypt((real_packet_t*)packet, &vp, cl->key); - add_mac_addresses(&vp); + if(debug_lvl >= DEBUG_PROTOCOL) + syslog(LOG_DEBUG, _("Purging unreachable nodes")); - 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; -cp - return 0; -} + for(nnode = node_tree->head; nnode; nnode = nnext) + { + nnext = nnode->next; + n = (node_t *)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 - if(debug_lvl > 3) - syslog(LOG_DEBUG, "packet to queue: %d", s); - - e = xmalloc(sizeof(*e)); - e->packet = xmalloc(s); - memcpy(e->packet, packet, s); - - if(!*q) + if(!n->status.reachable) { - *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; - } + if(debug_lvl >= DEBUG_SCARY_THINGS) + syslog(LOG_DEBUG, _("Purging node %s (%s)"), n->name, n->hostname); - (*q)->tail = e; -cp -} - -/* Remove a queue element */ -void del_queue(packet_queue_t **q, queue_element_t *e) -{ -cp - free(e->packet); + for(snode = n->subnet_tree->head; snode; snode = snext) + { + snext = snode->next; + s = (subnet_t *)snode->data; - 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 :) */ + for(cnode = connection_tree->head; cnode; cnode = cnode->next) { - e->prev->next = NULL; - (*q)->tail = e->prev; + c = (connection_t *)cnode->data; + if(c->status.active) + send_del_subnet(c, s); } - else /* Adieu */ - { - free(*q); - *q = NULL; - } - } - - free(e); -cp -} - -/* - 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 -} - -/* - 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 > 1) - syslog(LOG_DEBUG, "Flushing send queue for " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); - flush_queue(cl, &(cl->sq), xsend); - } + subnet_del(n, s); + } - if(cl->rq) - { - if(debug_lvl > 1) - syslog(LOG_DEBUG, "Flushing receive queue for " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); - flush_queue(cl, &(cl->rq), xrecv); - } -cp -} + for(enode = n->edge_tree->head; enode; enode = enext) + { + enext = enode->next; + e = (edge_t *)enode->data; -/* - 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 > 2) + for(cnode = connection_tree->head; cnode; cnode = cnode->next) { - syslog(LOG_NOTICE, "trying to look up " IP_ADDR_S " in connection list failed.", - IP_ADDR_V(to)); + c = (connection_t *)cnode->data; + if(c->status.active) + send_del_edge(c, e); } - for(cl = conn_list; cl != NULL && !cl->status.outgoing; cl = cl->next); - if(!cl) - { /* No open outgoing connection has been found. */ - if(debug_lvl > 2) - syslog(LOG_NOTICE, "There is no remote host I can send this packet to."); - return -1; - } - } - - if(my_key_expiry <= time(NULL)) - regenerate_keys(); - - if(!cl->status.dataopen) - if(setup_vpn_connection(cl) < 0) - return -1; - - if(!cl->status.validkey) - { - 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) - { - add_queue(&(cl->sq), packet, packet->len + 2); - if(debug_lvl > 1) - syslog(LOG_INFO, IP_ADDR_S " is not ready, queueing packet.", IP_ADDR_V(cl->vpn_ip)); - 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); -} - -int send_broadcast(conn_list_t *cl, vpn_packet_t *packet) -{ - conn_list_t *p; -cp - for(p = cl; p != NULL; p = p->next) - if(send_packet(p->real_ip, packet) < 0) - { - syslog(LOG_ERR, "Could not send a broadcast packet to %08lx (%08lx): %m", - p->vpn_ip, p->real_ip); - break; /* FIXME: should retry later, and send a ping over the metaconnection. */ + edge_del(e); } -cp - return 0; -} -/* - 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; + node_del(n); } - - tap_fd = nfd; + } cp - return 0; } /* - set up the socket that we listen on for incoming - (tcp) connections + put all file descriptors in an fd_set array + While we're at it, purge stuff that needs to be removed. */ -int setup_listen_meta_socket(int port) +void build_fdset(fd_set *fs) { - int nfd, flags; - struct sockaddr_in a; - const int one = 1; + avl_node_t *node, *next; + connection_t *c; + int i; cp - if((nfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) - { - syslog(LOG_ERR, "Creating metasocket failed: %m"); - return -1; - } + FD_ZERO(fs); - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) + for(node = connection_tree->head; node; node = next) { - syslog(LOG_ERR, "setsockopt: %m"); - return -1; - } + next = node->next; + c = (connection_t *)node->data; - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, "fcntl: %m"); - return -1; + if(c->status.remove) + connection_del(c); + else + FD_SET(c->socket, fs); } - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - a.sin_addr.s_addr = htonl(INADDR_ANY); + if(!connection_tree->head) + purge(); - if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr))) + for(i = 0; i < listen_sockets; i++) { - syslog(LOG_ERR, "Can't bind to port %hd/tcp: %m", port); - return -1; + FD_SET(listen_socket[i].tcp, fs); + FD_SET(listen_socket[i].udp, fs); } - if(listen(nfd, 3)) - { - syslog(LOG_ERR, "listen: %m"); - return -1; - } + FD_SET(device_fd, fs); cp - return nfd; } /* - setup the socket for incoming encrypted - data (the udp part) + Terminate a connection: + - Close the socket + - Remove associated edge and tell other connections about it if report = 1 + - Check if we need to retry making an outgoing connection + - Deactivate the host */ -int setup_vpn_in_socket(int port) +void terminate_connection(connection_t *c, int report) { - int nfd, flags; - struct sockaddr_in a; - const int one = 1; + avl_node_t *node; + connection_t *other; cp - if((nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) - { - syslog(LOG_ERR, "Creating socket failed: %m"); - return -1; - } + if(c->status.remove) + return; - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) - { - syslog(LOG_ERR, "setsockopt: %m"); - return -1; - } + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Closing connection with %s (%s)"), + c->name, c->hostname); - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, "fcntl: %m"); - return -1; - } + c->status.remove = 1; + c->status.active = 0; - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - a.sin_addr.s_addr = htonl(INADDR_ANY); + if(c->node) + c->node->connection = NULL; - 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->socket) + close(c->socket); -/* - 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((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) + if(c->edge) { - syslog(LOG_ERR, "Creating socket failed: %m"); - return -1; - } + if(report) + { + for(node = connection_tree->head; node; node = node->next) + { + other = (connection_t *)node->data; + if(other->status.active && other != c) + send_del_edge(other, c->edge); + } + } - a.sin_family = AF_INET; - a.sin_port = htons(cl->port); - a.sin_addr.s_addr = htonl(cl->real_ip); + edge_del(c->edge); - if(connect(cl->meta_socket, (struct sockaddr *)&a, sizeof(a)) == -1) - { - syslog(LOG_ERR, IP_ADDR_S ":%d: %m", IP_ADDR_V(cl->real_ip), cl->port); - return -1; - } + /* Run MST and SSSP algorithms */ - flags = fcntl(cl->meta_socket, F_GETFL); - if(fcntl(cl->meta_socket, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, "fcntl: %m"); - return -1; + graph(); } - cl->hostname = hostlookup(htonl(cl->real_ip)); - - syslog(LOG_INFO, "Connected to %s:%hd" , cl->hostname, cl->port); -cp - return 0; -} + /* Check if this was our outgoing connection */ -/* - 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(ip_t ip) -{ - conn_list_t *ncn; -cp - ncn = new_conn_list(); - ncn->real_ip = ip; - - if(setup_outgoing_meta_socket(ncn) < 0) + if(c->outgoing) { - syslog(LOG_ERR, "Could not set up a meta connection."); - free_conn_element(ncn); - return -1; + retry_outgoing(c->outgoing); + c->outgoing = NULL; } - - ncn->status.meta = 1; - ncn->status.outgoing = 1; - ncn->next = conn_list; - conn_list = ncn; cp - return 0; } /* - 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) +void check_dead_connections(void) { - config_t const *cfg; + avl_node_t *node, *next; + connection_t *c; cp - myself = new_conn_list(); - - if(!(cfg = get_config_val(myvpnip))) + for(node = connection_tree->head; node; node = next) { - syslog(LOG_ERR, "No value for my VPN IP given"); - return -1; - } - - myself->vpn_ip = cfg->data.ip->ip; - myself->vpn_mask = cfg->data.ip->mask; - - if(!(cfg = get_config_val(listenport))) - myself->port = 655; - else - myself->port = cfg->data.val; - - 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 %d.", myself->port); -cp - return 0; -} - -/* - setup all initial network connections -*/ -int setup_network_connections(void) -{ - config_t const *cfg; -cp - if((cfg = get_config_val(pingtimeout)) == NULL) - timeout = 10; - else - timeout = cfg->data.val; - - if(setup_tap_fd() < 0) - return -1; - - if(setup_myself() < 0) - return -1; - - if((cfg = get_config_val(upstreamip)) == NULL) - /* No upstream IP given, we're listen only. */ - return 0; - - if(setup_outgoing_connection(cfg->data.ip->ip)) - return -1; -cp - return 0; -} - -RETSIGTYPE -sigalrm_handler(int a) -{ - config_t const *cfg; - static int seconds_till_retry; -cp - cfg = get_config_val(upstreamip); - - if(!setup_outgoing_connection(cfg->data.ip->ip)) - { - signal(SIGALRM, SIG_IGN); - seconds_till_retry = 5; - } - else - { - signal(SIGALRM, sigalrm_handler); - seconds_till_retry += 5; - alarm(seconds_till_retry); - syslog(LOG_ERR, "Still failed to connect to other. Will retry in %d seconds.", - seconds_till_retry); - } -cp -} - -/* - 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); + 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(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_WARNING, _("Timeout from %s (%s) during authentication"), + c->name, c->hostname); + terminate_connection(c, 0); + } } } - - 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 + check all connections to see if anything + happened on their sockets */ -int setup_vpn_connection(conn_list_t *cl) +void check_network_activity(fd_set *f) { - int nfd, flags; - struct sockaddr_in a; + connection_t *c; + avl_node_t *node; + int result, i; + int len = sizeof(result); + vpn_packet_t packet; cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, "Opening UDP socket to " IP_ADDR_S, IP_ADDR_V(cl->real_ip)); - - nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); - if(nfd == -1) - { - syslog(LOG_ERR, "Creating data 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) + if(FD_ISSET(device_fd, f)) { - syslog(LOG_ERR, "Create connection to %08lx:%d failed: %m", ntohs(cl->real_ip), - cl->port); - return -1; + if(!read_packet(&packet)) + route_outgoing(&packet); } - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) + for(node = connection_tree->head; node; node = node->next) { - syslog(LOG_ERR, "This is a bug: %s:%d: %d:%m", __FILE__, __LINE__, nfd); - return -1; - } + c = (connection_t *)node->data; - cl->socket = nfd; - cl->status.dataopen = 1; -cp - return 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->hostname = hostlookup(ci.sin_addr.s_addr); - p->real_ip = ntohl(ci.sin_addr.s_addr); - p->meta_socket = sfd; - p->status.meta = 1; - - syslog(LOG_NOTICE, "Connection from %s:%d", p->hostname, htons(ci.sin_port)); - - if(send_basic_info(p) < 0) - { - free(p); - return NULL; - } -cp - return p; -} + if(c->status.remove) + continue; -/* - 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 -} - -/* - 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", __FILE__, __LINE__, cl->socket); - return -1; - } - if(x) - { - syslog(LOG_ERR, "Incoming data socket error: %s", sys_errlist[x]); - return -1; + 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; + } + } } - rp.len = -1; - lenin = recvfrom(cl->socket, &rp, MTU, 0, NULL, NULL); - if(lenin <= 0) + for(i = 0; i < listen_sockets; i++) { - syslog(LOG_ERR, "Receiving data failed: %m"); - return -1; - } - total_socket_in += lenin; - if(rp.len >= 0) - { - f = lookup_conn(rp.from); - if(debug_lvl > 3) - syslog(LOG_DEBUG, "packet from " IP_ADDR_S " (len %d)", - IP_ADDR_V(rp.from), rp.len); - if(!f) - { - syslog(LOG_ERR, "Got packet from unknown source " IP_ADDR_S, - IP_ADDR_V(rp.from)); - return -1; - } - - if(f->status.validkey) - xrecv(f, &rp); - else - { - add_queue(&(f->rq), &rp, rp.len); - if(!cl->status.waitingforkey) - send_key_request(rp.from); - } - - if(my_key_expiry <= time(NULL)) - regenerate_keys(); + 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 - return 0; } /* - terminate a connection and notify the other - end before closing the sockets + this is where it all happens... */ -void terminate_connection(conn_list_t *cl) +void main_loop(void) { + fd_set fset; + struct timeval tv; + int r; + time_t last_ping_check; + event_t *event; cp - if(cl->status.remove) - return; - - if(debug_lvl > 0) - syslog(LOG_NOTICE, "Closing connection with %s.", cl->hostname); - - if(cl->status.timeout) - send_timeout(cl); - else if(!cl->status.termreq) - send_termreq(cl); + last_ping_check = now; - close(cl->socket); - if(cl->status.meta) - close(cl->meta_socket); + srand(now); - if(cl->status.outgoing) - { - alarm(5); - signal(SIGALRM, sigalrm_handler); - syslog(LOG_NOTICE, "Try to re-establish outgoing connection in 5 seconds."); - } - - cl->status.remove = 1; -cp -} - -/* - send out a ping request to all active - connections -*/ -int send_broadcast_ping(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) + for(;;) { - if(p->status.remove) - continue; - if(p->status.active && p->status.meta) - { - if(send_ping(p)) - terminate_connection(p); - else - { - p->status.pinged = 1; - p->status.got_pong = 0; - } - } - } + now = time(NULL); - last_ping_time = time(NULL); -cp - return 0; -} - -/* - end all connections that did not respond - to the ping probe in time -*/ -int check_dead_connections(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - if(p->status.active && p->status.meta && p->status.pinged && !p->status.got_pong) - { - syslog(LOG_INFO, "%s (" IP_ADDR_S ") didn't respond to ping", - p->hostname, IP_ADDR_V(p->vpn_ip)); - p->status.timeout = 1; - terminate_connection(p); - } - } -cp - return 0; -} + tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */ + tv.tv_usec = 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; - } + build_fdset(&fset); - if((ncn = create_new_connection(nfd)) == NULL) - { - shutdown(nfd, 2); - close(nfd); - syslog(LOG_NOTICE, "Closed attempted connection."); - return 0; - } + 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; + } - ncn->status.meta = 1; - ncn->next = conn_list; - conn_list = ncn; -cp - return 0; -} + continue; + } -/* - dispatch any incoming meta requests -*/ -int handle_incoming_meta_data(conn_list_t *cl) -{ - int x, l = sizeof(x); - unsigned char tmp[1600]; - int request; - 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", __FILE__, __LINE__, cl->meta_socket); - return -1; - } - if(x) - { - syslog(LOG_ERR, "Metadata socket error: %s", sys_errlist[x]); - return -1; - } + check_network_activity(&fset); - if(read(cl->meta_socket, &tmp, 1) <= 0) - { - syslog(LOG_ERR, "Receive failed: %m"); - return -1; - } + if(do_purge) + { + purge(); + do_purge = 0; + } - request = (int)(tmp[0]); + /* Let's check if everybody is still alive */ - if(debug_lvl > 3) - syslog(LOG_DEBUG, "got request %d", request); + if(last_ping_check + pingtimeout < now) + { + check_dead_connections(); + last_ping_check = now; - if(request_handlers[request] == NULL) - syslog(LOG_ERR, "Unknown request %d.", request); - else - if(request_handlers[request](cl) < 0) - return -1; -cp - return 0; -} + if(routing_mode== RMODE_SWITCH) + age_mac(); -/* - 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: %s", sys_errlist[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); + age_past_requests(); - if(FD_ISSET(myself->meta_socket, f)) - handle_new_meta_connection(myself); -cp -} + /* Should we regenerate our key? */ -/* - 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; - } + if(keyexpires < now) + { + if(debug_lvl >= DEBUG_STATUS) + syslog(LOG_INFO, _("Regenerating symmetric key")); - total_tap_in += lenin; +#ifdef USE_OPENSSL + RAND_pseudo_bytes(myself->key, myself->keylength); +#endif + send_key_changed(myself->connection, myself); + keyexpires = now + keylifetime; + } + } - ether_type = ntohs(*((unsigned short*)(&vp.data[12]))); - if(ether_type != 0x0800) - { - if(debug_lvl > 0) - syslog(LOG_INFO, "Non-IP ethernet frame %04x from " MAC_ADDR_S, - ether_type, MAC_ADDR_V(vp.data[6])); - return; - } - - if(lenin < 32) - { - if(debug_lvl > 0) - syslog(LOG_INFO, "Dropping short packet"); - return; - } - from = ntohl(*((unsigned long*)(&vp.data[26]))); - to = ntohl(*((unsigned long*)(&vp.data[30]))); + while((event = get_expired_event())) + { + event->handler(event->data); + free(event); + } - if(debug_lvl > 3) - syslog(LOG_DEBUG, "An IP packet (%04x) for " IP_ADDR_S " from " IP_ADDR_S, - ether_type, IP_ADDR_V(to), IP_ADDR_V(from)); - if(debug_lvl > 4) - syslog(LOG_DEBUG, MAC_ADDR_S " to " MAC_ADDR_S, - MAC_ADDR_V(vp.data[0]), MAC_ADDR_V(vp.data[6])); - - vp.len = (length_t)lenin - 2; + 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; + } - strip_mac_addresses(&vp); + if(sighup) + { + sighup = 0; + close_network_connections(); + exit_configuration(&config_tree); - send_packet(to, &vp); -cp -} + syslog(LOG_INFO, _("Rereading configuration file and restarting in 5 seconds...")); + sleep(5); -/* - this is where it all happens... -*/ -void main_loop(void) -{ - fd_set fset; - struct timeval tv; - int r; -cp - last_ping_time = time(NULL); + init_configuration(&config_tree); - for(;;) - { - tv.tv_sec = timeout; - tv.tv_usec = 0; + if(read_server_config()) + { + syslog(LOG_ERR, _("Unable to reread configuration file, exitting.")); + exit(1); + } - prune_conn_list(); - build_fdset(&fset); + if(setup_network_connections()) + return; - if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0) - { - if(errno == EINTR) /* because of alarm */ - continue; - syslog(LOG_ERR, "Error while waiting for input: %m"); - return; + continue; } - - if(r == 0 || last_ping_time + timeout < time(NULL)) - /* Timeout... hm... something might be wrong. */ - { - check_dead_connections(); - send_broadcast_ping(); - continue; - } - - check_network_activity(&fset); - - /* local tap data */ - if(FD_ISSET(tap_fd, &fset)) - handle_tap_input(); } cp }