Add the AutoConnect option.

When set to a non-zero value, tinc will try to maintain exactly that number of
meta connections to other nodes.  If there are not enough connections, it will
periodically try to set up an outgoing connection to a random node.  If there
are too many connections, it will periodically try to remove an outgoing
connection.

src/net_setup.c

@@ -50,6 +50,7 @@ char *proxyport;
 char *proxyuser;
 char *proxypass;
 proxytype_t proxytype;
+int autoconnect;
 
 char *scriptinterpreter;
 char *scriptextension;
@@ -347,6 +348,36 @@ void load_all_subnets(void) {
 	closedir(dir);
 }
 
+void load_all_nodes(void) {
+	DIR *dir;
+	struct dirent *ent;
+	char *dname;
+
+	xasprintf(&dname, "%s" SLASH "hosts", confbase);
+	dir = opendir(dname);
+	if(!dir) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
+		free(dname);
+		return;
+	}
+
+	while((ent = readdir(dir))) {
+		if(!check_id(ent->d_name))
+			continue;
+
+		node_t *n = lookup_node(ent->d_name);
+		if(n)
+			continue;
+
+		n = new_node();
+		n->name = xstrdup(ent->d_name);
+		node_add(n);
+	}
+
+	closedir(dir);
+}
+
+
 char *get_name(void) {
 	char *name = NULL;
 
@@ -570,6 +601,8 @@ bool setup_myself_reloadable(void) {
 	if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 		keylifetime = 3600;
 
+	get_config_int(lookup_config(config_tree, "AutoConnect"), &autoconnect);
+
 	return true;
 }
 
@@ -730,6 +763,8 @@ static bool setup_myself(void) {
 
 	if(strictsubnets)
 		load_all_subnets();
+	else if(autoconnect)
+		load_all_nodes();
 
 	/* Open device */