X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=e9aed34c48ba74b72fd08f765427c628430bceb8;hp=b333c5b7b05777595ede76205b18921953a7f70e;hb=46f3eba7755089ff68fdc137b0754cae2fa523eb;hpb=717ea66d7ba0c23f27d86b3d5c6992b751135455

diff --git a/src/net.c b/src/net.c
index b333c5b7..e9aed34c 100644
--- a/src/net.c
+++ b/src/net.c
@@ -1,7 +1,7 @@
 /*
     net.c -- most of the network code
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2012 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>
 
@@ -22,24 +22,28 @@
 
 #include "system.h"
 
-#include "utils.h"
+#include "autoconnect.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 "utils.h"
 #include "xalloc.h"
 
 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;
+static struct timeval last_periodic_run_time;
 
 /* Purge edges and subnets of unreachable nodes. Use carefully. */
 
@@ -54,13 +58,17 @@ void purge(void) {
 
 			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);
 			}
 		}
@@ -71,16 +79,35 @@ void purge(void) {
 	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 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
@@ -91,31 +118,36 @@ void purge(void) {
 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);
+				}
 			}
 		}
 	}
@@ -125,8 +157,16 @@ void terminate_connection(connection_t *c, bool report) {
 
 	/* 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
 }
 
 /*
@@ -137,37 +177,92 @@ void terminate_connection(connection_t *c, bool report) {
   end does not reply in time, we consider them dead
   and close the connection.
 */
-static void timeout_handler(int fd, short events, void *event) {
-	time_t now = time(NULL);
+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) {
-			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 - c->last_ping_time);
-				} else if(c->last_ping_time + pinginterval <= now) {
-					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);
 		}
 	}
 
-	event_add(event, &(struct timeval){pingtimeout, 0});
+	timeout_set(data, &(struct timeval) {
+		1, rand() % 100000
+	});
 }
 
-static void periodic_handler(int fd, short events, void *event) {
+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.
@@ -175,14 +270,20 @@ static void periodic_handler(int fd, short events, void *event) {
 
 	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;
@@ -191,139 +292,48 @@ static void periodic_handler(int fd, short events, void *event) {
 	/* 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 = xmalloc_and_zero(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();
 	}
 
-	event_add(event, &(struct timeval){5, 0});
+	timeout_set(data, &(struct timeval) {
+		5, rand() % 100000
+	});
 }
 
-void handle_meta_connection_data(int fd, short events, void *data) {
-	connection_t *c = data;
-	int result;
-	socklen_t len = sizeof result;
-
-	if(c->status.connecting) {
-		c->status.connecting = false;
-
-		getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
-
-		if(!result)
-			finish_connecting(c);
-		else {
-			logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Error while connecting to %s (%s): %s", c->name, c->hostname, sockstrerror(result));
-			terminate_connection(c, false);
-			return;
+void handle_meta_connection_data(connection_t *c) {
+	if(!receive_meta(c)) {
+		if(!c->status.control) {
+			c->status.tarpit = true;
 		}
-	}
 
-	if (!receive_meta(c)) {
-		terminate_connection(c, c->status.active);
+		terminate_connection(c, c->edge);
 		return;
 	}
 }
 
-static void sigterm_handler(int signal, short events, void *data) {
-	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(signal));
-	event_loopexit(NULL);
+#ifndef HAVE_MINGW
+static void sigterm_handler(void *data) {
+	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
+	event_exit();
 }
 
-static void sighup_handler(int signal, short events, void *data) {
-	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(signal));
+static void sighup_handler(void *data) {
+	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
 	reopenlogger();
-	reload_configuration();
+
+	if(reload_configuration()) {
+		exit(1);
+	}
 }
 
-static void sigalrm_handler(int signal, short events, void *data) {
-	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(signal));
+static void sigalrm_handler(void *data) {
+	logger(DEBUG_ALWAYS, LOG_NOTICE, "Got %s signal", strsignal(((signal_t *)data)->signum));
 	retry();
 }
+#endif
 
 int reload_configuration(void) {
-	char *fname;
+	char fname[PATH_MAX];
 
 	/* Reread our own configuration file */
 
@@ -331,16 +341,14 @@ int reload_configuration(void) {
 	init_configuration(&config_tree);
 
 	if(!read_server_config()) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Unable to reread configuration file, exitting.");
-		event_loopexit(NULL);
+		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 */
 
@@ -350,40 +358,60 @@ int reload_configuration(void) {
 
 	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))
+			if(!get_config_subnet(cfg, &subnet)) {
 				continue;
+			}
 
 			if((s2 = lookup_subnet(myself, subnet))) {
-				if(s2->expires == 1)
+				if(s2->expires == 1) {
 					s2->expires = 0;
+				}
 
 				free_subnet(subnet);
 			} else {
@@ -411,78 +439,89 @@ int reload_configuration(void) {
 	/* 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 = time(NULL);
+	last_config_check = now.tv_sec;
 
 	return 0;
 }
 
 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
+		});
+	}
+
+	/* 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(timeout_initialized(&c->outgoing->ev))
-				event_del(&c->outgoing->ev);
-			if(c->status.connecting)
-				close(c->socket);
-			c->outgoing->timeout = 0;
-			terminate_connection(c, c->status.active);
+			c->last_ping_time = 0;
 		}
 	}
+
+	/* Kick the ping timeout handler */
+	timeout_set(&pingtimer, &(struct timeval) {
+		0, 0
+	});
 }
 
 /*
   this is where it all happens...
 */
 int main_loop(void) {
-	struct event timeout_event;
-	struct event periodic_event;
-
-	timeout_set(&timeout_event, timeout_handler, &timeout_event);
-	event_add(&timeout_event, &(struct timeval){pingtimeout, 0});
-
-	timeout_set(&periodic_event, periodic_handler, &periodic_event);
-	event_add(&periodic_event, &(struct timeval){5, 0});
+	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
-	struct event sighup_event;
-	struct event sigterm_event;
-	struct event sigquit_event;
-	struct event sigalrm_event;
-
-	signal_set(&sighup_event, SIGHUP, sighup_handler, NULL);
-	signal_add(&sighup_event, NULL);
-	signal_set(&sigterm_event, SIGTERM, sigterm_handler, NULL);
-	signal_add(&sigterm_event, NULL);
-	signal_set(&sigquit_event, SIGQUIT, sigterm_handler, NULL);
-	signal_add(&sigquit_event, NULL);
-	signal_set(&sigalrm_event, SIGALRM, sigalrm_handler, NULL);
-	signal_add(&sigalrm_event, NULL);
+	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
 
-	if(event_loop(0) < 0) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", strerror(errno));
+	if(!event_loop()) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno));
 		return 1;
 	}
 
 #ifndef HAVE_MINGW
-	signal_del(&sighup_event);
-	signal_del(&sigterm_event);
-	signal_del(&sigquit_event);
-	signal_del(&sigalrm_event);
+	signal_del(&sighup);
+	signal_del(&sigterm);
+	signal_del(&sigquit);
+	signal_del(&sigint);
+	signal_del(&sigalrm);
 #endif
 
-	event_del(&timeout_event);
+	timeout_del(&periodictimer);
+	timeout_del(&pingtimer);
 
 	return 0;
 }