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;
32 bool strictsubnets = false;
33 bool experimental = false;
35 /* Jumptable for the request handlers */
37 static bool (*request_handlers[])(connection_t *, char *) = {
38 id_h, metakey_h, challenge_h, chal_reply_h, ack_h,
39 status_h, error_h, termreq_h,
41 add_subnet_h, del_subnet_h,
42 add_edge_h, del_edge_h,
43 key_changed_h, req_key_h, ans_key_h, tcppacket_h, control_h,
48 static char (*request_name[]) = {
49 "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK",
50 "STATUS", "ERROR", "TERMREQ",
52 "ADD_SUBNET", "DEL_SUBNET",
53 "ADD_EDGE", "DEL_EDGE", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", "PACKET", "CONTROL",
56 static splay_tree_t *past_request_tree;
58 bool check_id(const char *id) {
60 if(!isalnum(*id) && *id != '_')
66 /* Generic request routines - takes care of logging and error
69 bool send_request(connection_t *c, const char *format, ...) {
71 char request[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(request, 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);
90 logger(LOG_DEBUG, "Sending %s to %s (%s): %s",
91 request_name[atoi(request)], c->name, c->hostname, request);
93 logger(LOG_DEBUG, "Sending %s to %s (%s)", request_name[atoi(request)],
94 c->name, c->hostname);
97 request[len++] = '\n';
100 broadcast_meta(NULL, request, len);
103 return send_meta(c, request, len);
106 void forward_request(connection_t *from, char *request) {
107 /* Note: request is not zero terminated anymore after a call to this function! */
110 logger(LOG_DEBUG, "Forwarding %s from %s (%s): %s",
111 request_name[atoi(request)], from->name, from->hostname, request);
113 logger(LOG_DEBUG, "Forwarding %s from %s (%s)",
114 request_name[atoi(request)], from->name, from->hostname);
117 int len = strlen(request);
118 request[len++] = '\n';
119 broadcast_meta(from, request, len);
122 bool receive_request(connection_t *c, char *request) {
123 int reqno = atoi(request);
125 if(reqno || *request == '0') {
126 if((reqno < 0) || (reqno >= LAST) || !request_handlers[reqno]) {
128 logger(LOG_DEBUG, "Unknown request from %s (%s): %s",
129 c->name, c->hostname, request);
131 logger(LOG_ERR, "Unknown request from %s (%s)",
132 c->name, c->hostname);
138 logger(LOG_DEBUG, "Got %s from %s (%s): %s",
139 request_name[reqno], c->name, c->hostname, request);
141 logger(LOG_DEBUG, "Got %s from %s (%s)",
142 request_name[reqno], c->name, c->hostname);
146 if((c->allow_request != ALL) && (c->allow_request != reqno)) {
147 logger(LOG_ERR, "Unauthorized request from %s (%s)", c->name,
152 if(!request_handlers[reqno](c, request)) {
153 /* Something went wrong. Probably scriptkiddies. Terminate. */
155 logger(LOG_ERR, "Error while processing %s from %s (%s)",
156 request_name[reqno], c->name, c->hostname);
160 logger(LOG_ERR, "Bogus data received from %s (%s)",
161 c->name, c->hostname);
168 static int past_request_compare(const past_request_t *a, const past_request_t *b) {
169 return strcmp(a->request, b->request);
172 static void free_past_request(past_request_t *r) {
179 static struct event past_request_event;
181 bool seen_request(char *request) {
182 past_request_t *new, p = {NULL};
186 if(splay_search(past_request_tree, &p)) {
187 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Already seen request");
190 new = xmalloc(sizeof *new);
191 new->request = xstrdup(request);
192 new->firstseen = time(NULL);
193 splay_insert(past_request_tree, new);
194 event_add(&past_request_event, &(struct timeval){10, 0});
199 static void age_past_requests(int fd, short events, void *data) {
200 splay_node_t *node, *next;
202 int left = 0, deleted = 0;
203 time_t now = time(NULL);
205 for(node = past_request_tree->head; node; node = next) {
209 if(p->firstseen + pinginterval <= now)
210 splay_delete_node(past_request_tree, node), deleted++;
216 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Aging past requests: deleted %d, left %d",
220 event_add(&past_request_event, &(struct timeval){10, 0});
223 void init_requests(void) {
224 past_request_tree = splay_alloc_tree((splay_compare_t) past_request_compare, (splay_action_t) free_past_request);
226 timeout_set(&past_request_event, age_past_requests, NULL);
229 void exit_requests(void) {
230 splay_delete_tree(past_request_tree);
232 if(timeout_initialized(&past_request_event))
233 event_del(&past_request_event);