/*
net.c -- most of the network code
Copyright (C) 1998-2005 Ivo Timmermans,
- 2000-2015 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2017 Guus Sliepen <guus@tinc-vpn.org>
2006 Scott Lamb <slamb@slamb.org>
2011 Loïc Grenié <loic.grenie@gmail.com>
#include "system.h"
-#include "utils.h"
+#include "autoconnect.h"
#include "conf.h"
#include "connection.h"
#include "device.h"
#include "netutl.h"
#include "protocol.h"
#include "subnet.h"
+#include "utils.h"
#include "xalloc.h"
int contradicting_add_edge = 0;
time_t last_config_check = 0;
static timeout_t pingtimer;
static timeout_t periodictimer;
+static struct timeval last_periodic_run_time;
/* Purge edges and subnets of unreachable nodes. Use carefully. */
void terminate_connection(connection_t *c, bool report) {
logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Closing connection with %s (%s)", c->name, c->hostname);
- if(c->node && c->node->connection == c)
- c->node->connection = NULL;
+ if(c->node) {
+ if(c->node->connection == c)
+ c->node->connection = NULL;
- if(c->edge) {
- if(report && !tunnelserver)
- send_del_edge(everyone, c->edge);
+ if(c->edge) {
+ if(report && !tunnelserver)
+ send_del_edge(everyone, c->edge);
- edge_del(c->edge);
- c->edge = NULL;
+ edge_del(c->edge);
+ c->edge = NULL;
- /* Run MST and SSSP algorithms */
+ /* Run MST and SSSP algorithms */
- graph();
+ graph();
- /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
+ /* 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);
+ 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);
+ }
}
}
}
and close the connection.
*/
static void timeout_handler(void *data) {
+
+ bool close_all_connections = false;
+
+ /*
+ timeout_handler will start after 30 seconds from start of tincd
+ hold information about the elapsed time since last time the handler
+ has been run
+ */
+ long sleep_time = now.tv_sec - last_periodic_run_time.tv_sec;
+ /*
+ It seems that finding sane default value is harder than expected
+ Since we send every second a UDP packet to make holepunching work
+ And default UDP state expire on firewalls is between 15-30 seconds
+ we drop all connections after 60 Seconds - UDPDiscoveryTimeout=30
+ by default
+ */
+ if (sleep_time > 2 * udp_discovery_timeout) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Awaking from dead after %ld seconds of sleep", sleep_time);
+ /*
+ Do not send any packets to tinc after we wake up.
+ The other node probably closed our connection but we still
+ are holding context information to them. This may happen on
+ laptops or any other hardware which can be suspended for some time.
+ Sending any data to node that wasn't expecting it will produce
+ annoying and misleading errors on the other side about failed signature
+ verification and or about missing sptps context
+ */
+ close_all_connections = true;
+ }
+ last_periodic_run_time = now;
+
for list_each(connection_t, c, connection_list) {
+ // control connections (eg. tinc ctl) do not have any timeout
if(c->status.control)
continue;
- if(c->last_ping_time + pingtimeout <= now.tv_sec) {
- if(c->edge) {
- try_tx(c->node, false);
- if(c->status.pinged) {
- 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);
- continue;
- } else {
- continue;
- }
- } 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);
- }
+ if(close_all_connections) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Forcing connection close after sleep time %s (%s)", c->name, c->hostname);
+ terminate_connection(c, c->edge);
+ continue;
+ }
+
+ // Bail out early if we haven't reached the ping timeout for this node yet
+ if(c->last_ping_time + pingtimeout > now.tv_sec)
+ continue;
+
+ // timeout during connection establishing
+ if(!c->edge) {
+ 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);
+ continue;
+ }
+
+ // helps in UDP holepunching
+ try_tx(c->node, false);
+
+ // timeout during ping
+ if(c->status.pinged) {
+ 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));
terminate_connection(c, c->edge);
+ continue;
}
+ // check whether we need to send a new ping
+ if(c->last_ping_time + pinginterval <= now.tv_sec)
+ send_ping(c);
}
timeout_set(data, &(struct timeval){1, rand() % 100000});
/* 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 count = 0;
- for splay_each(node_t, n, node_tree) {
- if(n == myself || n->connection || !(n->status.has_address || n->status.reachable))
- continue;
- count++;
- }
-
- if(!count)
- goto end;
-
- int r = rand() % count;
-
- for splay_each(node_t, n, node_tree) {
- if(n == myself || n->connection || !(n->status.has_address || n->status.reachable))
- continue;
-
- if(r--)
- continue;
-
- 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(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);
- }
- }
- }
- }
+ if(autoconnect && node_tree->count > 1)
+ do_autoconnect();
-end:
timeout_set(data, &(struct timeval){5, rand() % 100000});
}
this is where it all happens...
*/
int main_loop(void) {
+ last_periodic_run_time = now;
timeout_add(&pingtimer, timeout_handler, &pingtimer, &(struct timeval){pingtimeout, rand() % 100000});
timeout_add(&periodictimer, periodic_handler, &periodictimer, &(struct timeval){0, 0});