/*
net.c -- most of the network code
Copyright (C) 1998-2005 Ivo Timmermans,
- 2000-2013 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2021 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_net.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 "protocol.h"
#include "subnet.h"
-#include "xalloc.h"
+#include "utils.h"
int contradicting_add_edge = 0;
int contradicting_del_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. */
for splay_each(subnet_t, s, n->subnet_tree) {
send_del_subnet(everyone, s);
- if(!strictsubnets)
+
+ if(!strictsubnets) {
subnet_del(n, s);
+ }
}
for splay_each(edge_t, e, n->edge_tree) {
- if(!tunnelserver)
+ if(!tunnelserver) {
send_del_edge(everyone, e);
+ }
+
edge_del(e);
}
}
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)
+ if(e->to == n) {
return;
+ }
if(!autoconnect && (!strictsubnets || !n->subnet_tree->head))
/* in strictsubnets mode do not delete nodes with subnets */
+ {
node_del(n);
+ }
}
}
}
+/* Put a misbehaving connection in the tarpit */
+void tarpit(int fd) {
+ static int pits[10] = {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1};
+ static unsigned int next_pit = 0;
+
+ if(pits[next_pit] != -1) {
+ closesocket(pits[next_pit]);
+ }
+
+ pits[next_pit++] = fd;
+
+ if(next_pit >= sizeof pits / sizeof pits[0]) {
+ next_pit = 0;
+ }
+}
+
/*
Terminate a connection:
- Mark it as inactive
void terminate_connection(connection_t *c, bool report) {
logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Closing connection with %s (%s)", c->name, c->hostname);
- c->status.active = false;
+ if(c->node) {
+ if(c->node->connection == c) {
+ c->node->connection = NULL;
+ }
- if(c->node && 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(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(e) {
+ if(!tunnelserver) {
+ send_del_edge(everyone, e);
+ }
+
+ edge_del(e);
+ }
}
}
}
/* Check if this was our outgoing connection */
- if(outgoing)
+ if(outgoing) {
do_outgoing_connection(outgoing);
+ }
#ifndef HAVE_MINGW
/* Clean up dead proxy processes */
while(waitpid(-1, NULL, WNOHANG) > 0);
+
#endif
}
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) {
- if(c->status.control)
+ // 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->status.active) {
- 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;
- }
+ 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 {
- 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);
+ logger(DEBUG_CONNECTIONS, LOG_WARNING, "Timeout from %s (%s) during authentication", c->name, c->hostname);
+ c->status.tarpit = true;
}
- terminate_connection(c, c->status.active);
+
+ 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){pingtimeout, rand() % 100000});
+ timeout_set(data, &(struct timeval) {
+ 1, rand() % 100000
+ });
}
static void periodic_handler(void *data) {
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);
- usleep(sleeptime * 1000000LL);
+ nanosleep(&(struct timespec) {
+ sleeptime, 0
+ }, NULL);
sleeptime *= 2;
- if(sleeptime < 0)
+
+ if(sleeptime < 0) {
sleeptime = 3600;
+ }
} else {
sleeptime /= 2;
- if(sleeptime < 10)
+
+ if(sleeptime < 10) {
sleeptime = 10;
+ }
}
contradicting_add_edge = 0;
/* 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->status.active && !c->status.control)
- nc++;
- }
-
- if(nc < autoconnect) {
- /* 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;
- int i = 0;
-
- for splay_each(node_t, n, node_tree) {
- 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 > autoconnect) {
- /* 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->status.active || c->status.control)
- 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->status.active);
- break;
- }
- }
-
- if(nc >= autoconnect) {
- /* 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);
- }
- }
- }
+ do_autoconnect();
}
- timeout_set(data, &(struct timeval){5, rand() % 100000});
+ timeout_set(data, &(struct timeval) {
+ 5, rand() % 100000
+ });
}
void handle_meta_connection_data(connection_t *c) {
- if (!receive_meta(c)) {
- terminate_connection(c, c->status.active);
+ if(!receive_meta(c)) {
+ if(!c->status.control) {
+ c->status.tarpit = true;
+ }
+
+ terminate_connection(c, c->edge);
return;
}
}
static void sighup_handler(void *data) {
logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
reopenlogger();
- if(reload_configuration())
+
+ if(reload_configuration()) {
exit(1);
+ }
}
static void sigalrm_handler(void *data) {
#endif
int reload_configuration(void) {
- char *fname = NULL;
+ char fname[PATH_MAX];
/* Reread our own configuration file */
exit_configuration(&config_tree);
init_configuration(&config_tree);
- if(!read_server_config()) {
+ if(!read_server_config(config_tree)) {
logger(DEBUG_ALWAYS, LOG_ERR, "Unable to reread configuration file.");
return EINVAL;
}
read_config_options(config_tree, NULL);
- xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, myself->name);
- read_config_file(config_tree, fname);
- free(fname);
+ snprintf(fname, sizeof(fname), "%s" SLASH "hosts" SLASH "%s", confbase, myself->name);
+ read_config_file(config_tree, fname, true);
/* Parse some options that are allowed to be changed while tinc is running */
if(strictsubnets) {
for splay_each(subnet_t, subnet, subnet_tree)
- subnet->expires = 1;
+ if(subnet->owner) {
+ subnet->expires = 1;
+ }
+ }
+
+ for splay_each(node_t, n, node_tree) {
+ n->status.has_address = false;
+ }
- load_all_subnets();
+ load_all_nodes();
+ if(strictsubnets) {
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)
+
+ 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)
+
+ 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)
+ if(!subnet->expires) {
subnet->expires = 1;
+ }
config_t *cfg = lookup_config(config_tree, "Subnet");
while(cfg) {
subnet_t *subnet, *s2;
- if(!get_config_subnet(cfg, &subnet))
- continue;
-
- if((s2 = lookup_subnet(myself, subnet))) {
- if(s2->expires == 1)
- s2->expires = 0;
+ if(get_config_subnet(cfg, &subnet)) {
+ if((s2 = lookup_subnet(myself, subnet))) {
+ if(s2->expires == 1) {
+ s2->expires = 0;
+ }
- free_subnet(subnet);
- } else {
- subnet_add(myself, subnet);
- send_add_subnet(everyone, subnet);
- subnet_update(myself, subnet, true);
+ free_subnet(subnet);
+ } else {
+ subnet_add(myself, subnet);
+ send_add_subnet(everyone, subnet);
+ subnet_update(myself, subnet, true);
+ }
}
cfg = lookup_config_next(config_tree, cfg);
/* Close connections to hosts that have a changed or deleted host config file */
for list_each(connection_t, c, connection_list) {
- if(c->status.control)
+ if(c->status.control) {
continue;
+ }
- xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, c->name);
+ 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->status.active);
+ terminate_connection(c, c->edge);
}
- free(fname);
}
last_config_check = now.tv_sec;
/* 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});
+ timeout_set(&outgoing->ev, &(struct timeval) {
+ 0, 0
+ });
}
/* 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)
+ if(c->outgoing && !c->node) {
c->last_ping_time = 0;
+ }
}
/* Kick the ping timeout handler */
- timeout_set(&pingtimer, &(struct timeval){0, 0});
+ timeout_set(&pingtimer, &(struct timeval) {
+ 0, 0
+ });
}
/*
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){pingtimeout, rand() % 100000});
+ 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
+ });
#ifndef HAVE_MINGW
signal_t sighup = {0};
#endif
if(!event_loop()) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", strerror(errno));
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno));
return 1;
}