Send one MTU probe at a time.
[tinc] / src / protocol_edge.c
1 /*
2     protocol_edge.c -- handle the meta-protocol, edges
3     Copyright (C) 1999-2005 Ivo Timmermans,
4                   2000-2012 Guus Sliepen <guus@tinc-vpn.org>
5                   2009      Michael Tokarev <mjt@corpit.ru>
6
7     This program is free software; you can redistribute it and/or modify
8     it under the terms of the GNU General Public License as published by
9     the Free Software Foundation; either version 2 of the License, or
10     (at your option) any later version.
11
12     This program is distributed in the hope that it will be useful,
13     but WITHOUT ANY WARRANTY; without even the implied warranty of
14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15     GNU General Public License for more details.
16
17     You should have received a copy of the GNU General Public License along
18     with this program; if not, write to the Free Software Foundation, Inc.,
19     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 */
21
22 #include "system.h"
23
24 #include "conf.h"
25 #include "connection.h"
26 #include "edge.h"
27 #include "graph.h"
28 #include "logger.h"
29 #include "meta.h"
30 #include "net.h"
31 #include "netutl.h"
32 #include "node.h"
33 #include "protocol.h"
34 #include "utils.h"
35 #include "xalloc.h"
36
37 bool send_add_edge(connection_t *c, const edge_t *e) {
38         bool x;
39         char *address, *port;
40         char *local_address, *local_port;
41
42         sockaddr2str(&e->address, &address, &port);
43         sockaddr2str(&e->local_address, &local_address, &local_port);
44
45         x = send_request(c, "%d %x %s %s %s %s %x %d %s %s", ADD_EDGE, rand(),
46                                          e->from->name, e->to->name, address, port,
47                                          e->options, e->weight, local_address, local_port);
48
49         free(address);
50         free(port);
51         free(local_address);
52         free(local_port);
53
54         return x;
55 }
56
57 bool add_edge_h(connection_t *c, const char *request) {
58         edge_t *e;
59         node_t *from, *to;
60         char from_name[MAX_STRING_SIZE];
61         char to_name[MAX_STRING_SIZE];
62         char to_address[MAX_STRING_SIZE];
63         char to_port[MAX_STRING_SIZE];
64         char address_local[MAX_STRING_SIZE] = "unknown";
65         char port_local[MAX_STRING_SIZE] = "unknown";
66         sockaddr_t address, local_address;
67         uint32_t options;
68         int weight;
69
70         int parameter_count = sscanf(request, "%*d %*x "MAX_STRING" "MAX_STRING" "MAX_STRING" "MAX_STRING" %x %d "MAX_STRING" "MAX_STRING,
71                                               from_name, to_name, to_address, to_port, &options, &weight, address_local, port_local);
72         if (parameter_count != 6 && parameter_count != 8) {
73                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ADD_EDGE", c->name,
74                            c->hostname);
75                 return false;
76         }
77
78         /* Check if names are valid */
79
80         if(!check_id(from_name) || !check_id(to_name)) {
81                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ADD_EDGE", c->name,
82                            c->hostname, "invalid name");
83                 return false;
84         }
85
86         if(seen_request(request))
87                 return true;
88
89         /* Lookup nodes */
90
91         from = lookup_node(from_name);
92         to = lookup_node(to_name);
93
94         if(tunnelserver &&
95            from != myself && from != c->node &&
96            to != myself && to != c->node) {
97                 /* ignore indirect edge registrations for tunnelserver */
98                 logger(DEBUG_PROTOCOL, LOG_WARNING,
99                    "Ignoring indirect %s from %s (%s)",
100                    "ADD_EDGE", c->name, c->hostname);
101                 return true;
102         }
103
104         if(!from) {
105                 from = new_node();
106                 from->name = xstrdup(from_name);
107                 node_add(from);
108         }
109
110         if(!to) {
111                 to = new_node();
112                 to->name = xstrdup(to_name);
113                 node_add(to);
114         }
115
116
117         /* Convert addresses */
118
119         address = str2sockaddr(to_address, to_port);
120         local_address = str2sockaddr(address_local, port_local);
121
122         /* Check if edge already exists */
123
124         e = lookup_edge(from, to);
125
126         if(e) {
127                 if(e->weight != weight || e->options != options || sockaddrcmp(&e->address, &address) || sockaddrcmp(&e->local_address, &local_address)) {
128                         if(from == myself) {
129                                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself which does not match existing entry",
130                                                    "ADD_EDGE", c->name, c->hostname);
131                                 send_add_edge(c, e);
132                                 return true;
133                         } else {
134                                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) which does not match existing entry",
135                                                    "ADD_EDGE", c->name, c->hostname);
136                                 edge_del(e);
137                                 graph();
138                         }
139                 } else
140                         return true;
141         } else if(from == myself) {
142                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself which does not exist",
143                                    "ADD_EDGE", c->name, c->hostname);
144                 contradicting_add_edge++;
145                 e = new_edge();
146                 e->from = from;
147                 e->to = to;
148                 send_del_edge(c, e);
149                 free_edge(e);
150                 return true;
151         }
152
153         e = new_edge();
154         e->from = from;
155         e->to = to;
156         e->address = address;
157         e->local_address = local_address;
158         e->options = options;
159         e->weight = weight;
160         edge_add(e);
161
162         /* Tell the rest about the new edge */
163
164         if(!tunnelserver)
165                 forward_request(c, request);
166
167         /* Run MST before or after we tell the rest? */
168
169         graph();
170
171         return true;
172 }
173
174 bool send_del_edge(connection_t *c, const edge_t *e) {
175         return send_request(c, "%d %x %s %s", DEL_EDGE, rand(),
176                                                 e->from->name, e->to->name);
177 }
178
179 bool del_edge_h(connection_t *c, const char *request) {
180         edge_t *e;
181         char from_name[MAX_STRING_SIZE];
182         char to_name[MAX_STRING_SIZE];
183         node_t *from, *to;
184
185         if(sscanf(request, "%*d %*x "MAX_STRING" "MAX_STRING, from_name, to_name) != 2) {
186                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "DEL_EDGE", c->name,
187                            c->hostname);
188                 return false;
189         }
190
191         /* Check if names are valid */
192
193         if(!check_id(from_name) || !check_id(to_name)) {
194                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "DEL_EDGE", c->name,
195                            c->hostname, "invalid name");
196                 return false;
197         }
198
199         if(seen_request(request))
200                 return true;
201
202         /* Lookup nodes */
203
204         from = lookup_node(from_name);
205         to = lookup_node(to_name);
206
207         if(tunnelserver &&
208            from != myself && from != c->node &&
209            to != myself && to != c->node) {
210                 /* ignore indirect edge registrations for tunnelserver */
211                 logger(DEBUG_PROTOCOL, LOG_WARNING,
212                    "Ignoring indirect %s from %s (%s)",
213                    "DEL_EDGE", c->name, c->hostname);
214                 return true;
215         }
216
217         if(!from) {
218                 logger(DEBUG_PROTOCOL, LOG_ERR, "Got %s from %s (%s) which does not appear in the edge tree",
219                                    "DEL_EDGE", c->name, c->hostname);
220                 return true;
221         }
222
223         if(!to) {
224                 logger(DEBUG_PROTOCOL, LOG_ERR, "Got %s from %s (%s) which does not appear in the edge tree",
225                                    "DEL_EDGE", c->name, c->hostname);
226                 return true;
227         }
228
229         /* Check if edge exists */
230
231         e = lookup_edge(from, to);
232
233         if(!e) {
234                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) which does not appear in the edge tree",
235                                    "DEL_EDGE", c->name, c->hostname);
236                 return true;
237         }
238
239         if(e->from == myself) {
240                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself",
241                                    "DEL_EDGE", c->name, c->hostname);
242                 contradicting_del_edge++;
243                 send_add_edge(c, e);    /* Send back a correction */
244                 return true;
245         }
246
247         /* Tell the rest about the deleted edge */
248
249         if(!tunnelserver)
250                 forward_request(c, request);
251
252         /* Delete the edge */
253
254         edge_del(e);
255
256         /* Run MST before or after we tell the rest? */
257
258         graph();
259
260         /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
261
262         if(!to->status.reachable) {
263                 e = lookup_edge(to, myself);
264                 if(e) {
265                         if(!tunnelserver)
266                                 send_del_edge(everyone, e);
267                         edge_del(e);
268                 }
269         }
270
271         return true;
272 }