/*
net.c -- most of the network code
- Copyright (C) 1998-2002 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2002 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 1998-2005 Ivo Timmermans,
+ 2000-2015 Guus Sliepen <guus@tinc-vpn.org>
+ 2006 Scott Lamb <slamb@slamb.org>
+ 2011 Loïc Grenié <loic.grenie@gmail.com>
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
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 1.35.4.182 2002/09/15 14:55:53 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 <errno.h>
-#include <fcntl.h>
-#include <netdb.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <signal.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <syslog.h>
-#include <unistd.h>
-#include <sys/ioctl.h>
-/* SunOS really wants sys/socket.h BEFORE net/if.h,
- and FreeBSD wants these lines below the rest. */
-#include <arpa/inet.h>
-#include <sys/socket.h>
-#include <net/if.h>
-#ifdef HAVE_NETINET_IN_SYSTM_H
-#include <netinet/in_systm.h>
-#endif
-#include <netinet/in.h>
-#ifdef HAVE_NETINET_IP_H
-#include <netinet/ip.h>
-#endif
-#ifdef HAVE_NETINET_TCP_H
-#include <netinet/tcp.h>
-#endif
-
-#include <openssl/rand.h>
-
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
-#include <list.h>
+#include "system.h"
+#include "utils.h"
#include "conf.h"
#include "connection.h"
+#include "device.h"
+#include "graph.h"
+#include "logger.h"
#include "meta.h"
+#include "names.h"
#include "net.h"
#include "netutl.h"
-#include "process.h"
#include "protocol.h"
#include "subnet.h"
-#include "graph.h"
-#include "process.h"
-#include "route.h"
-#include "device.h"
-#include "event.h"
-
-#include "system.h"
-
-#ifndef HAVE_RAND_PSEUDO_BYTES
-#define RAND_pseudo_bytes RAND_bytes
-#endif
-
-int do_purge = 0;
-int sighup = 0;
-int sigalrm = 0;
+#include "xalloc.h"
-time_t now = 0;
+int contradicting_add_edge = 0;
+int contradicting_del_edge = 0;
+static int sleeptime = 10;
+time_t last_config_check = 0;
+static timeout_t pingtimer;
+static timeout_t periodictimer;
/* Purge edges and subnets of unreachable nodes. Use carefully. */
-void purge(void)
-{
- avl_node_t *nnode, *nnext, *enode, *enext, *snode, *snext;
- node_t *n;
- edge_t *e;
- subnet_t *s;
+void purge(void) {
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "Purging unreachable nodes");
- cp();
-
- if(debug_lvl >= DEBUG_PROTOCOL)
- syslog(LOG_DEBUG, _("Purging unreachable nodes"));
-
- for(nnode = node_tree->head; nnode; nnode = nnext) {
- nnext = nnode->next;
- n = (node_t *) nnode->data;
+ /* Remove all edges and subnets owned by unreachable nodes. */
+ for splay_each(node_t, n, node_tree) {
if(!n->status.reachable) {
- if(debug_lvl >= DEBUG_SCARY_THINGS)
- syslog(LOG_DEBUG, _("Purging node %s (%s)"), n->name,
- n->hostname);
-
- for(snode = n->subnet_tree->head; snode; snode = snext) {
- snext = snode->next;
- s = (subnet_t *) snode->data;
- send_del_subnet(broadcast, s);
- subnet_del(n, s);
+ logger(DEBUG_SCARY_THINGS, LOG_DEBUG, "Purging node %s (%s)", n->name, n->hostname);
+
+ for splay_each(subnet_t, s, n->subnet_tree) {
+ send_del_subnet(everyone, s);
+ if(!strictsubnets)
+ subnet_del(n, s);
}
- for(enode = n->edge_tree->head; enode; enode = enext) {
- enext = enode->next;
- e = (edge_t *) enode->data;
- send_del_edge(broadcast, e);
+ for splay_each(edge_t, e, n->edge_tree) {
+ if(!tunnelserver)
+ send_del_edge(everyone, e);
edge_del(e);
}
-
- node_del(n);
}
}
-}
-/*
- put all file descriptors in an fd_set array
- While we're at it, purge stuff that needs to be removed.
-*/
-void build_fdset(fd_set * fs)
-{
- avl_node_t *node, *next;
- connection_t *c;
- int i;
-
- cp();
-
- FD_ZERO(fs);
-
- for(node = connection_tree->head; node; node = next) {
- next = node->next;
- c = (connection_t *) node->data;
-
- if(c->status.remove) {
- connection_del(c);
- if(!connection_tree->head)
- purge();
- } else
- FD_SET(c->socket, fs);
- }
+ /* Check if anyone else claims to have an edge to an unreachable node. If not, delete node. */
- for(i = 0; i < listen_sockets; i++) {
- FD_SET(listen_socket[i].tcp, fs);
- FD_SET(listen_socket[i].udp, fs);
- }
+ for splay_each(node_t, n, node_tree) {
+ if(!n->status.reachable) {
+ for splay_each(edge_t, e, edge_weight_tree)
+ if(e->to == n)
+ return;
- FD_SET(device_fd, fs);
+ if(!autoconnect && (!strictsubnets || !n->subnet_tree->head))
+ /* in strictsubnets mode do not delete nodes with subnets */
+ node_del(n);
+ }
+ }
}
/*
Terminate a connection:
- - Close the socket
- - Remove associated edge and tell other connections about it if report = 1
+ - Mark it as inactive
+ - Remove the edge representing this connection
+ - Kill it with fire
- Check if we need to retry making an outgoing connection
- - Deactivate the host
*/
-void terminate_connection(connection_t *c, int report)
-{
- cp();
-
- if(c->status.remove)
- return;
-
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Closing connection with %s (%s)"),
- c->name, c->hostname);
+void terminate_connection(connection_t *c, bool report) {
+ logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Closing connection with %s (%s)", c->name, c->hostname);
- c->status.remove = 1;
- c->status.active = 0;
-
- if(c->node)
+ if(c->node && c->node->connection == c)
c->node->connection = NULL;
- if(c->socket)
- close(c->socket);
-
if(c->edge) {
- if(report)
- send_del_edge(broadcast, c->edge);
+ if(report && !tunnelserver)
+ send_del_edge(everyone, c->edge);
edge_del(c->edge);
+ c->edge = NULL;
/* Run MST and SSSP algorithms */
graph();
+
+ /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
+
+ if(report && !c->node->status.reachable) {
+ edge_t *e;
+ e = lookup_edge(c->node, myself);
+ if(e) {
+ if(!tunnelserver)
+ send_del_edge(everyone, e);
+ edge_del(e);
+ }
+ }
}
+ outgoing_t *outgoing = c->outgoing;
+ connection_del(c);
+
/* Check if this was our outgoing connection */
- if(c->outgoing) {
- retry_outgoing(c->outgoing);
- c->outgoing = NULL;
- }
+ if(outgoing)
+ do_outgoing_connection(outgoing);
+
+#ifndef HAVE_MINGW
+ /* Clean up dead proxy processes */
+
+ while(waitpid(-1, NULL, WNOHANG) > 0);
+#endif
}
/*
end does not reply in time, we consider them dead
and close the connection.
*/
-void check_dead_connections(void)
-{
- avl_node_t *node, *next;
- connection_t *c;
-
- cp();
-
- for(node = connection_tree->head; node; node = next) {
- next = node->next;
- c = (connection_t *) node->data;
+static void timeout_handler(void *data) {
+ for list_each(connection_t, c, connection_list) {
+ if(c->status.control)
+ continue;
- if(c->last_ping_time + pingtimeout < now) {
- if(c->status.active) {
+ if(c->last_ping_time + pingtimeout <= now.tv_sec) {
+ if(c->edge) {
+ try_tx(c->node, false);
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 {
+ logger(DEBUG_CONNECTIONS, LOG_INFO, "%s (%s) didn't respond to PING in %ld seconds", c->name, c->hostname, (long)(now.tv_sec - c->last_ping_time));
+ } else if(c->last_ping_time + pinginterval <= now.tv_sec) {
send_ping(c);
- }
- } else {
- if(c->status.remove) {
- syslog(LOG_WARNING, _("Old connection_t for %s (%s) status %04x still lingering, deleting..."),
- c->name, c->hostname, c->status);
- connection_del(c);
+ continue;
+ } else {
continue;
}
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_WARNING, _("Timeout from %s (%s) during authentication"),
- c->name, c->hostname);
- terminate_connection(c, 0);
+ } else {
+ if(c->status.connecting)
+ logger(DEBUG_CONNECTIONS, LOG_WARNING, "Timeout while connecting to %s (%s)", c->name, c->hostname);
+ else
+ logger(DEBUG_CONNECTIONS, LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname);
}
+ terminate_connection(c, c->edge);
}
+
}
+
+ timeout_set(data, &(struct timeval){1, rand() % 100000});
}
-/*
- check all connections to see if anything
- happened on their sockets
-*/
-void check_network_activity(fd_set * f)
-{
- connection_t *c;
- avl_node_t *node;
- int result, i;
- int len = sizeof(result);
- vpn_packet_t packet;
-
- cp();
-
- if(FD_ISSET(device_fd, f)) {
- if(!read_packet(&packet))
- route_outgoing(&packet);
+static void periodic_handler(void *data) {
+ /* Check if there are too many contradicting ADD_EDGE and DEL_EDGE messages.
+ This usually only happens when another node has the same Name as this node.
+ If so, sleep for a short while to prevent a storm of contradicting messages.
+ */
+
+ if(contradicting_del_edge > 100 && contradicting_add_edge > 100) {
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Possible node with same Name as us! Sleeping %d seconds.", sleeptime);
+ nanosleep(&(struct timespec){sleeptime, 0}, NULL);
+ sleeptime *= 2;
+ if(sleeptime < 0)
+ sleeptime = 3600;
+ } else {
+ sleeptime /= 2;
+ if(sleeptime < 10)
+ sleeptime = 10;
}
- for(node = connection_tree->head; node; node = node->next) {
- c = (connection_t *) node->data;
+ contradicting_add_edge = 0;
+ contradicting_del_edge = 0;
- if(c->status.remove)
- continue;
+ /* If AutoConnect is set, check if we need to make or break connections. */
+
+ if(autoconnect && node_tree->count > 1) {
+ /* Count number of active connections */
+ int nc = 0;
+ for list_each(connection_t, c, connection_list) {
+ if(c->edge)
+ nc++;
+ }
+
+ if(nc < 3) {
+ /* Not enough active connections, try to add one.
+ Choose a random node, if we don't have a connection to it,
+ and we are not already trying to make one, create an
+ outgoing connection to this node.
+ */
+ int r = rand() % (node_tree->count - 1);
+ int i = 0;
+
+ for splay_each(node_t, n, node_tree) {
+ if(n == myself)
+ continue;
- if(FD_ISSET(c->socket, f)) {
- if(c->status.connecting) {
- c->status.connecting = 0;
- getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
-
- if(!result)
- finish_connecting(c);
- else {
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_DEBUG,
- _("Error while connecting to %s (%s): %s"),
- c->name, c->hostname, strerror(result));
- close(c->socket);
- do_outgoing_connection(c);
+ if(i++ != r)
continue;
+
+ if(n->connection)
+ break;
+
+ bool found = false;
+
+ for list_each(outgoing_t, outgoing, outgoing_list) {
+ if(!strcmp(outgoing->name, n->name)) {
+ found = true;
+ break;
+ }
+ }
+
+ if(!found) {
+ logger(DEBUG_CONNECTIONS, LOG_INFO, "Autoconnecting to %s", n->name);
+ outgoing_t *outgoing = xzalloc(sizeof *outgoing);
+ outgoing->name = xstrdup(n->name);
+ list_insert_tail(outgoing_list, outgoing);
+ setup_outgoing_connection(outgoing);
}
+ break;
}
+ } else if(nc > 3) {
+ /* Too many active connections, try to remove one.
+ Choose a random outgoing connection to a node
+ that has at least one other connection.
+ */
+ int r = rand() % nc;
+ int i = 0;
+
+ for list_each(connection_t, c, connection_list) {
+ if(!c->edge)
+ continue;
- if(receive_meta(c) < 0) {
- terminate_connection(c, c->status.active);
- continue;
+ if(i++ != r)
+ continue;
+
+ if(!c->outgoing || !c->node || c->node->edge_tree->count < 2)
+ break;
+
+ logger(DEBUG_CONNECTIONS, LOG_INFO, "Autodisconnecting from %s", c->name);
+ list_delete(outgoing_list, c->outgoing);
+ c->outgoing = NULL;
+ terminate_connection(c, c->edge);
+ break;
+ }
+ }
+
+ if(nc >= 3) {
+ /* If we have enough active connections,
+ remove any pending outgoing connections.
+ */
+ for list_each(outgoing_t, o, outgoing_list) {
+ bool found = false;
+ for list_each(connection_t, c, connection_list) {
+ if(c->outgoing == o) {
+ found = true;
+ break;
+ }
+ }
+ if(!found) {
+ logger(DEBUG_CONNECTIONS, LOG_INFO, "Cancelled outgoing connection to %s", o->name);
+ list_delete_node(outgoing_list, node);
+ }
}
}
}
- for(i = 0; i < listen_sockets; i++) {
- if(FD_ISSET(listen_socket[i].udp, f))
- handle_incoming_vpn_data(listen_socket[i].udp);
+ timeout_set(data, &(struct timeval){5, rand() % 100000});
+}
- if(FD_ISSET(listen_socket[i].tcp, f))
- handle_new_meta_connection(listen_socket[i].tcp);
+void handle_meta_connection_data(connection_t *c) {
+ if (!receive_meta(c)) {
+ terminate_connection(c, c->edge);
+ return;
}
}
-/*
- this is where it all happens...
-*/
-void main_loop(void)
-{
- fd_set fset;
- struct timeval tv;
- int r;
- time_t last_ping_check;
- event_t *event;
+#ifndef HAVE_MINGW
+static void sigterm_handler(void *data) {
+ logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
+ event_exit();
+}
- cp();
+static void sighup_handler(void *data) {
+ logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
+ reopenlogger();
+ if(reload_configuration())
+ exit(1);
+}
- last_ping_check = now;
- srand(now);
+static void sigalrm_handler(void *data) {
+ logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
+ retry();
+}
+#endif
- for(;;) {
- now = time(NULL);
+int reload_configuration(void) {
+ char fname[PATH_MAX];
- tv.tv_sec = 1 + (rand() & 7); /* Approx. 5 seconds, randomized to prevent global synchronisation effects */
- tv.tv_usec = 0;
+ /* Reread our own configuration file */
- build_fdset(&fset);
+ exit_configuration(&config_tree);
+ init_configuration(&config_tree);
- r = select(FD_SETSIZE, &fset, NULL, NULL, &tv);
+ if(!read_server_config()) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Unable to reread configuration file.");
+ return EINVAL;
+ }
- if(r < 0) {
- if(errno != EINTR && errno != EAGAIN) {
- syslog(LOG_ERR, _("Error while waiting for input: %s"),
- strerror(errno));
- cp_trace();
- dump_connections();
- return;
- }
+ read_config_options(config_tree, NULL);
- continue;
- }
+ snprintf(fname, sizeof fname, "%s" SLASH "hosts" SLASH "%s", confbase, myself->name);
+ read_config_file(config_tree, fname);
+
+ /* Parse some options that are allowed to be changed while tinc is running */
+
+ setup_myself_reloadable();
+
+ /* If StrictSubnet is set, expire deleted Subnets and read new ones in */
- check_network_activity(&fset);
+ if(strictsubnets) {
+ for splay_each(subnet_t, subnet, subnet_tree)
+ if (subnet->owner)
+ subnet->expires = 1;
- if(do_purge) {
- purge();
- do_purge = 0;
+ load_all_subnets();
+
+ for splay_each(subnet_t, subnet, subnet_tree) {
+ if (!subnet->owner)
+ continue;
+ if(subnet->expires == 1) {
+ send_del_subnet(everyone, subnet);
+ if(subnet->owner->status.reachable)
+ subnet_update(subnet->owner, subnet, false);
+ subnet_del(subnet->owner, subnet);
+ } else if(subnet->expires == -1) {
+ subnet->expires = 0;
+ } else {
+ send_add_subnet(everyone, subnet);
+ if(subnet->owner->status.reachable)
+ subnet_update(subnet->owner, subnet, true);
+ }
}
+ } else { /* Only read our own subnets back in */
+ for splay_each(subnet_t, subnet, myself->subnet_tree)
+ if(!subnet->expires)
+ subnet->expires = 1;
- /* Let's check if everybody is still alive */
+ config_t *cfg = lookup_config(config_tree, "Subnet");
- if(last_ping_check + pingtimeout < now) {
- check_dead_connections();
- last_ping_check = now;
+ while(cfg) {
+ subnet_t *subnet, *s2;
- if(routing_mode == RMODE_SWITCH)
- age_mac();
+ if(!get_config_subnet(cfg, &subnet))
+ continue;
- age_past_requests();
+ if((s2 = lookup_subnet(myself, subnet))) {
+ if(s2->expires == 1)
+ s2->expires = 0;
- /* Should we regenerate our key? */
+ free_subnet(subnet);
+ } else {
+ subnet_add(myself, subnet);
+ send_add_subnet(everyone, subnet);
+ subnet_update(myself, subnet, true);
+ }
- if(keyexpires < now) {
- if(debug_lvl >= DEBUG_STATUS)
- syslog(LOG_INFO, _("Regenerating symmetric key"));
+ cfg = lookup_config_next(config_tree, cfg);
+ }
- RAND_pseudo_bytes(myself->key, myself->keylength);
- send_key_changed(broadcast, myself);
- keyexpires = now + keylifetime;
+ for splay_each(subnet_t, subnet, myself->subnet_tree) {
+ if(subnet->expires == 1) {
+ send_del_subnet(everyone, subnet);
+ subnet_update(myself, subnet, false);
+ subnet_del(myself, subnet);
}
}
+ }
+ /* Try to make outgoing connections */
- while((event = get_expired_event())) {
- event->handler(event->data);
- free(event);
- }
+ try_outgoing_connections();
- if(sigalrm) {
- syslog(LOG_INFO, _("Flushing event queue"));
+ /* Close connections to hosts that have a changed or deleted host config file */
- while(event_tree->head) {
- event = (event_t *) event_tree->head->data;
- event->handler(event->data);
- event_del(event);
- }
- sigalrm = 0;
+ for list_each(connection_t, c, connection_list) {
+ if(c->status.control)
+ continue;
+
+ snprintf(fname, sizeof fname, "%s" SLASH "hosts" SLASH "%s", confbase, c->name);
+ struct stat s;
+ if(stat(fname, &s) || s.st_mtime > last_config_check) {
+ logger(DEBUG_CONNECTIONS, LOG_INFO, "Host config file of %s has been changed", c->name);
+ terminate_connection(c, c->edge);
}
+ }
+
+ last_config_check = now.tv_sec;
- if(sighup) {
- sighup = 0;
- close_network_connections();
- exit_configuration(&config_tree);
+ return 0;
+}
- syslog(LOG_INFO, _("Rereading configuration file and restarting in 5 seconds..."));
- sleep(5);
+void retry(void) {
+ /* Reset the reconnection timers for all outgoing connections */
+ for list_each(outgoing_t, outgoing, outgoing_list) {
+ outgoing->timeout = 0;
+ if(outgoing->ev.cb)
+ timeout_set(&outgoing->ev, &(struct timeval){0, 0});
+ }
- init_configuration(&config_tree);
+ /* Check for outgoing connections that are in progress, and reset their ping timers */
+ for list_each(connection_t, c, connection_list) {
+ if(c->outgoing && !c->node)
+ c->last_ping_time = 0;
+ }
- if(read_server_config()) {
- syslog(LOG_ERR,
- _("Unable to reread configuration file, exitting."));
- exit(1);
- }
+ /* Kick the ping timeout handler */
+ timeout_set(&pingtimer, &(struct timeval){0, 0});
+}
- if(setup_network_connections())
- return;
+/*
+ this is where it all happens...
+*/
+int main_loop(void) {
+ timeout_add(&pingtimer, timeout_handler, &pingtimer, &(struct timeval){pingtimeout, rand() % 100000});
+ timeout_add(&periodictimer, periodic_handler, &periodictimer, &(struct timeval){0, 0});
+
+#ifndef HAVE_MINGW
+ signal_t sighup = {0};
+ signal_t sigterm = {0};
+ signal_t sigquit = {0};
+ signal_t sigint = {0};
+ signal_t sigalrm = {0};
+
+ signal_add(&sighup, sighup_handler, &sighup, SIGHUP);
+ signal_add(&sigterm, sigterm_handler, &sigterm, SIGTERM);
+ signal_add(&sigquit, sigterm_handler, &sigquit, SIGQUIT);
+ signal_add(&sigint, sigterm_handler, &sigint, SIGINT);
+ signal_add(&sigalrm, sigalrm_handler, &sigalrm, SIGALRM);
+#endif
- continue;
- }
+ if(!event_loop()) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno));
+ return 1;
}
+
+#ifndef HAVE_MINGW
+ signal_del(&sighup);
+ signal_del(&sigterm);
+ signal_del(&sigquit);
+ signal_del(&sigint);
+ signal_del(&sigalrm);
+#endif
+
+ timeout_del(&periodictimer);
+ timeout_del(&pingtimer);
+
+ return 0;
}
projects / tinc / blobdiff