2 protocol.c -- handle the meta-protocol, basic functions
3 Copyright (C) 1999-2005 Ivo Timmermans,
4 2000-2009 Guus Sliepen <guus@tinc-vpn.org>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 #include "connection.h"
31 bool tunnelserver = false;
33 /* Jumptable for the request handlers */
35 static bool (*request_handlers[])(connection_t *) = {
36 id_h, metakey_h, challenge_h, chal_reply_h, ack_h,
37 status_h, error_h, termreq_h,
39 add_subnet_h, del_subnet_h,
40 add_edge_h, del_edge_h,
41 key_changed_h, req_key_h, ans_key_h, tcppacket_h,
46 static char (*request_name[]) = {
47 "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK",
48 "STATUS", "ERROR", "TERMREQ",
50 "ADD_SUBNET", "DEL_SUBNET",
51 "ADD_EDGE", "DEL_EDGE", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", "PACKET",
54 static avl_tree_t *past_request_tree;
56 bool check_id(const char *id) {
58 if(!isalnum(*id) && *id != '_')
64 /* Generic request routines - takes care of logging and error
67 bool send_request(connection_t *c, const char *format, ...) {
69 char buffer[MAXBUFSIZE];
74 /* Use vsnprintf instead of vxasprintf: faster, no memory
75 fragmentation, cleanup is automatic, and there is a limit on the
76 input buffer anyway */
78 va_start(args, format);
79 len = vsnprintf(buffer, MAXBUFSIZE, format, args);
82 if(len < 0 || len > MAXBUFSIZE - 1) {
83 logger(LOG_ERR, _("Output buffer overflow while sending request to %s (%s)"),
84 c->name, c->hostname);
89 sscanf(buffer, "%d", &request);
91 logger(LOG_DEBUG, _("Sending %s to %s (%s): %s"),
92 request_name[request], c->name, c->hostname, buffer);
94 logger(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request],
95 c->name, c->hostname);
101 broadcast_meta(NULL, buffer, len);
104 return send_meta(c, buffer, len);
107 void forward_request(connection_t *from) {
113 sscanf(from->buffer, "%d", &request);
115 logger(LOG_DEBUG, _("Forwarding %s from %s (%s): %s"),
116 request_name[request], from->name, from->hostname,
119 logger(LOG_DEBUG, _("Forwarding %s from %s (%s)"),
120 request_name[request], from->name, from->hostname);
123 from->buffer[from->reqlen - 1] = '\n';
125 broadcast_meta(from, from->buffer, from->reqlen);
128 bool receive_request(connection_t *c) {
133 if(sscanf(c->buffer, "%d", &request) == 1) {
134 if((request < 0) || (request >= LAST) || !request_handlers[request]) {
136 logger(LOG_DEBUG, _("Unknown request from %s (%s): %s"),
137 c->name, c->hostname, c->buffer);
139 logger(LOG_ERR, _("Unknown request from %s (%s)"),
140 c->name, c->hostname);
146 logger(LOG_DEBUG, _("Got %s from %s (%s): %s"),
147 request_name[request], c->name, c->hostname,
150 logger(LOG_DEBUG, _("Got %s from %s (%s)"),
151 request_name[request], c->name, c->hostname);
155 if((c->allow_request != ALL) && (c->allow_request != request)) {
156 logger(LOG_ERR, _("Unauthorized request from %s (%s)"), c->name,
161 if(!request_handlers[request](c)) {
162 /* Something went wrong. Probably scriptkiddies. Terminate. */
164 logger(LOG_ERR, _("Error while processing %s from %s (%s)"),
165 request_name[request], c->name, c->hostname);
169 logger(LOG_ERR, _("Bogus data received from %s (%s)"),
170 c->name, c->hostname);
177 static int past_request_compare(const past_request_t *a, const past_request_t *b) {
178 return strcmp(a->request, b->request);
181 static void free_past_request(past_request_t *r) {
190 void init_requests(void) {
193 past_request_tree = avl_alloc_tree((avl_compare_t) past_request_compare, (avl_action_t) free_past_request);
196 void exit_requests(void) {
199 avl_delete_tree(past_request_tree);
202 bool seen_request(char *request) {
203 past_request_t *new, p = {0};
209 if(avl_search(past_request_tree, &p)) {
210 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Already seen request"));
213 new = xmalloc(sizeof(*new));
214 new->request = xstrdup(request);
215 new->firstseen = now;
216 avl_insert(past_request_tree, new);
221 void age_past_requests(void) {
222 avl_node_t *node, *next;
224 int left = 0, deleted = 0;
228 for(node = past_request_tree->head; node; node = next) {
232 if(p->firstseen + pinginterval < now)
233 avl_delete_node(past_request_tree, node), deleted++;
239 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Aging past requests: deleted %d, left %d"),