www.tinc-vpn.org Git - tinc/blob - 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
  41         sockaddr2str(&e->address, &address, &port);
  42
  43         if(e->local_address.sa.sa_family) {
  44                 char *local_address, *local_port;
  45                 sockaddr2str(&e->local_address, &local_address, &local_port);
  46
  47                 x = send_request(c, "%d %x %s %s %s %s %x %d %s %s", ADD_EDGE, rand(),
  48                                                  e->from->name, e->to->name, address, port,
  49                                                  e->options, e->weight, local_address, local_port);
  50                 free(local_address);
  51                 free(local_port);
  52         } else {
  53                 x = send_request(c, "%d %x %s %s %s %s %x %d", ADD_EDGE, rand(),
  54                                                  e->from->name, e->to->name, address, port,
  55                                                  e->options, e->weight);
  56         }
  57
  58         free(address);
  59         free(port);
  60
  61         return x;
  62 }
  63
  64 bool add_edge_h(connection_t *c, const char *request) {
  65         edge_t *e;
  66         node_t *from, *to;
  67         char from_name[MAX_STRING_SIZE];
  68         char to_name[MAX_STRING_SIZE];
  69         char to_address[MAX_STRING_SIZE];
  70         char to_port[MAX_STRING_SIZE];
  71         char address_local[MAX_STRING_SIZE];
  72         char port_local[MAX_STRING_SIZE];
  73         sockaddr_t address, local_address = {{0}};
  74         uint32_t options;
  75         int weight;
  76
  77         int parameter_count = sscanf(request, "%*d %*x "MAX_STRING" "MAX_STRING" "MAX_STRING" "MAX_STRING" %x %d "MAX_STRING" "MAX_STRING,
  78                                               from_name, to_name, to_address, to_port, &options, &weight, address_local, port_local);
  79         if (parameter_count != 6 && parameter_count != 8) {
  80                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ADD_EDGE", c->name,
  81                            c->hostname);
  82                 return false;
  83         }
  84
  85         /* Check if names are valid */
  86
  87         if(!check_id(from_name) || !check_id(to_name)) {
  88                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ADD_EDGE", c->name,
  89                            c->hostname, "invalid name");
  90                 return false;
  91         }
  92
  93         if(seen_request(request))
  94                 return true;
  95
  96         /* Lookup nodes */
  97
  98         from = lookup_node(from_name);
  99         to = lookup_node(to_name);
 100
 101         if(tunnelserver &&
 102            from != myself && from != c->node &&
 103            to != myself && to != c->node) {
 104                 /* ignore indirect edge registrations for tunnelserver */
 105                 logger(DEBUG_PROTOCOL, LOG_WARNING,
 106                    "Ignoring indirect %s from %s (%s)",
 107                    "ADD_EDGE", c->name, c->hostname);
 108                 return true;
 109         }
 110
 111         if(!from) {
 112                 from = new_node();
 113                 from->name = xstrdup(from_name);
 114                 node_add(from);
 115         }
 116
 117         if(!to) {
 118                 to = new_node();
 119                 to->name = xstrdup(to_name);
 120                 node_add(to);
 121         }
 122
 123
 124         /* Convert addresses */
 125
 126         address = str2sockaddr(to_address, to_port);
 127         if(parameter_count >= 8)
 128                 local_address = str2sockaddr(address_local, port_local);
 129
 130         /* Check if edge already exists */
 131
 132         e = lookup_edge(from, to);
 133
 134         if(e) {
 135                 // local_address.sa.sa_family will be 0 if we got it from older tinc versions
 136                 // local_address.sa.sa_family will be 255 (AF_UNKNOWN) if we got it from newer versions
 137                 // but for edge which does not have local_address
 138                 bool new_local_address = local_address.sa.sa_family && local_address.sa.sa_family != AF_UNKNOWN &&
 139                         sockaddrcmp(&e->local_address, &local_address);
 140
 141                 if(e->weight != weight || e->options != options || sockaddrcmp(&e->address, &address) || new_local_address) {
 142                         if(from == myself) {
 143                                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself which does not match existing entry",
 144                                                    "ADD_EDGE", c->name, c->hostname);
 145                                 send_add_edge(c, e);
 146                                 sockaddrfree(&local_address);
 147                                 return true;
 148                         } else {
 149                                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) which does not match existing entry",
 150                                                    "ADD_EDGE", c->name, c->hostname);
 151                                 e->options = options;
 152                                 if(sockaddrcmp(&e->address, &address)) {
 153                                         sockaddrfree(&e->address);
 154                                         e->address = address;
 155                                 }
 156                                 if(new_local_address) {
 157                                         sockaddrfree(&e->local_address);
 158                                         e->local_address = local_address;
 159                                 }
 160                                 if(e->weight != weight) {
 161                                         splay_node_t *node = splay_unlink(edge_weight_tree, e);
 162                                         e->weight = weight;
 163                                         splay_insert_node(edge_weight_tree, node);
 164                                 }
 165
 166                                 goto done;
 167                         }
 168                 } else {
 169                         sockaddrfree(&local_address);
 170                         return true;
 171                 }
 172         } else if(from == myself) {
 173                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself which does not exist",
 174                                    "ADD_EDGE", c->name, c->hostname);
 175                 contradicting_add_edge++;
 176                 e = new_edge();
 177                 e->from = from;
 178                 e->to = to;
 179                 send_del_edge(c, e);
 180                 free_edge(e);
 181                 sockaddrfree(&local_address);
 182                 return true;
 183         }
 184
 185         e = new_edge();
 186         e->from = from;
 187         e->to = to;
 188         e->address = address;
 189         e->local_address = local_address;
 190         e->options = options;
 191         e->weight = weight;
 192         edge_add(e);
 193
 194 done:
 195         /* Tell the rest about the new edge */
 196
 197         if(!tunnelserver)
 198                 forward_request(c, request);
 199
 200         /* Run MST before or after we tell the rest? */
 201
 202         graph();
 203
 204         return true;
 205 }
 206
 207 bool send_del_edge(connection_t *c, const edge_t *e) {
 208         return send_request(c, "%d %x %s %s", DEL_EDGE, rand(),
 209                                                 e->from->name, e->to->name);
 210 }
 211
 212 bool del_edge_h(connection_t *c, const char *request) {
 213         edge_t *e;
 214         char from_name[MAX_STRING_SIZE];
 215         char to_name[MAX_STRING_SIZE];
 216         node_t *from, *to;
 217
 218         if(sscanf(request, "%*d %*x "MAX_STRING" "MAX_STRING, from_name, to_name) != 2) {
 219                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "DEL_EDGE", c->name,
 220                            c->hostname);
 221                 return false;
 222         }
 223
 224         /* Check if names are valid */
 225
 226         if(!check_id(from_name) || !check_id(to_name)) {
 227                 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "DEL_EDGE", c->name,
 228                            c->hostname, "invalid name");
 229                 return false;
 230         }
 231
 232         if(seen_request(request))
 233                 return true;
 234
 235         /* Lookup nodes */
 236
 237         from = lookup_node(from_name);
 238         to = lookup_node(to_name);
 239
 240         if(tunnelserver &&
 241            from != myself && from != c->node &&
 242            to != myself && to != c->node) {
 243                 /* ignore indirect edge registrations for tunnelserver */
 244                 logger(DEBUG_PROTOCOL, LOG_WARNING,
 245                    "Ignoring indirect %s from %s (%s)",
 246                    "DEL_EDGE", c->name, c->hostname);
 247                 return true;
 248         }
 249
 250         if(!from) {
 251                 logger(DEBUG_PROTOCOL, LOG_ERR, "Got %s from %s (%s) which does not appear in the edge tree",
 252                                    "DEL_EDGE", c->name, c->hostname);
 253                 return true;
 254         }
 255
 256         if(!to) {
 257                 logger(DEBUG_PROTOCOL, LOG_ERR, "Got %s from %s (%s) which does not appear in the edge tree",
 258                                    "DEL_EDGE", c->name, c->hostname);
 259                 return true;
 260         }
 261
 262         /* Check if edge exists */
 263
 264         e = lookup_edge(from, to);
 265
 266         if(!e) {
 267                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) which does not appear in the edge tree",
 268                                    "DEL_EDGE", c->name, c->hostname);
 269                 return true;
 270         }
 271
 272         if(e->from == myself) {
 273                 logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) for ourself",
 274                                    "DEL_EDGE", c->name, c->hostname);
 275                 contradicting_del_edge++;
 276                 send_add_edge(c, e);    /* Send back a correction */
 277                 return true;
 278         }
 279
 280         /* Tell the rest about the deleted edge */
 281
 282         if(!tunnelserver)
 283                 forward_request(c, request);
 284
 285         /* Delete the edge */
 286
 287         edge_del(e);
 288
 289         /* Run MST before or after we tell the rest? */
 290
 291         graph();
 292
 293         /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
 294
 295         if(!to->status.reachable) {
 296                 e = lookup_edge(to, myself);
 297                 if(e) {
 298                         if(!tunnelserver)
 299                                 send_del_edge(everyone, e);
 300                         edge_del(e);
 301                 }
 302         }
 303
 304         return true;
 305 }