tinc-vpn.org Git - tinc/blob - src/subnet.c

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2009 Guus Sliepen <guus@tinc-vpn.org>,
   4                   2000-2005 Ivo Timmermans
   5
   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.
  10
  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.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id$
  21 */
  22
  23 #include "system.h"
  24
  25 #include "avl_tree.h"
  26 #include "device.h"
  27 #include "logger.h"
  28 #include "net.h"
  29 #include "netutl.h"
  30 #include "node.h"
  31 #include "process.h"
  32 #include "subnet.h"
  33 #include "utils.h"
  34 #include "xalloc.h"
  35
  36 /* lists type of subnet */
  37
  38 avl_tree_t *subnet_tree;
  39
  40 /* Subnet lookup cache */
  41
  42 static ipv4_t cache_ipv4_address[2];
  43 static subnet_t *cache_ipv4_subnet[2];
  44 static bool cache_ipv4_valid[2];
  45 static int cache_ipv4_slot;
  46
  47 static ipv6_t cache_ipv6_address[2];
  48 static subnet_t *cache_ipv6_subnet[2];
  49 static bool cache_ipv6_valid[2];
  50 static int cache_ipv6_slot;
  51
  52 void subnet_cache_flush() {
  53         cache_ipv4_valid[0] = cache_ipv4_valid[1] = false;
  54         cache_ipv6_valid[0] = cache_ipv6_valid[1] = false;
  55 }
  56
  57 /* Subnet comparison */
  58
  59 static int subnet_compare_mac(const subnet_t *a, const subnet_t *b)
  60 {
  61         int result;
  62
  63         result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  64
  65         if(result)
  66                 return result;
  67
  68         result = a->weight - b->weight;
  69
  70         if(result || !a->owner || !b->owner)
  71                 return result;
  72
  73         return strcmp(a->owner->name, b->owner->name);
  74 }
  75
  76 static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b)
  77 {
  78         int result;
  79
  80         result = b->net.ipv4.prefixlength - a->net.ipv4.prefixlength;
  81
  82         if(result)
  83                 return result;
  84
  85         result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
  86
  87         if(result)
  88                 return result;
  89
  90         result = a->weight - b->weight;
  91
  92         if(result || !a->owner || !b->owner)
  93                 return result;
  94
  95         return strcmp(a->owner->name, b->owner->name);
  96 }
  97
  98 static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b)
  99 {
 100         int result;
 101
 102         result = b->net.ipv6.prefixlength - a->net.ipv6.prefixlength;
 103
 104         if(result)
 105                 return result;
 106
 107         result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
 108
 109         if(result)
 110                 return result;
 111
 112         result = a->weight - b->weight;
 113
 114         if(result || !a->owner || !b->owner)
 115                 return result;
 116
 117         return strcmp(a->owner->name, b->owner->name);
 118 }
 119
 120 int subnet_compare(const subnet_t *a, const subnet_t *b)
 121 {
 122         int result;
 123
 124         result = a->type - b->type;
 125
 126         if(result)
 127                 return result;
 128
 129         switch (a->type) {
 130         case SUBNET_MAC:
 131                 return subnet_compare_mac(a, b);
 132         case SUBNET_IPV4:
 133                 return subnet_compare_ipv4(a, b);
 134         case SUBNET_IPV6:
 135                 return subnet_compare_ipv6(a, b);
 136         default:
 137                 logger(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, exitting!"),
 138                            a->type);
 139                 cp_trace();
 140                 exit(0);
 141         }
 142
 143         return 0;
 144 }
 145
 146 /* Initialising trees */
 147
 148 void init_subnets(void)
 149 {
 150         cp();
 151
 152         subnet_tree = avl_alloc_tree((avl_compare_t) subnet_compare, (avl_action_t) free_subnet);
 153
 154         subnet_cache_flush();
 155 }
 156
 157 void exit_subnets(void)
 158 {
 159         cp();
 160
 161         avl_delete_tree(subnet_tree);
 162 }
 163
 164 avl_tree_t *new_subnet_tree(void)
 165 {
 166         cp();
 167
 168         return avl_alloc_tree((avl_compare_t) subnet_compare, NULL);
 169 }
 170
 171 void free_subnet_tree(avl_tree_t *subnet_tree)
 172 {
 173         cp();
 174
 175         avl_delete_tree(subnet_tree);
 176 }
 177
 178 /* Allocating and freeing space for subnets */
 179
 180 subnet_t *new_subnet(void)
 181 {
 182         cp();
 183
 184         return xmalloc_and_zero(sizeof(subnet_t));
 185 }
 186
 187 void free_subnet(subnet_t *subnet)
 188 {
 189         cp();
 190
 191         free(subnet);
 192 }
 193
 194 /* Adding and removing subnets */
 195
 196 void subnet_add(node_t *n, subnet_t *subnet)
 197 {
 198         cp();
 199
 200         subnet->owner = n;
 201
 202         avl_insert(subnet_tree, subnet);
 203         avl_insert(n->subnet_tree, subnet);
 204
 205         subnet_cache_flush();
 206 }
 207
 208 void subnet_del(node_t *n, subnet_t *subnet)
 209 {
 210         cp();
 211
 212         avl_delete(n->subnet_tree, subnet);
 213         avl_delete(subnet_tree, subnet);
 214
 215         subnet_cache_flush();
 216 }
 217
 218 /* Ascii representation of subnets */
 219
 220 bool str2net(subnet_t *subnet, const char *subnetstr)
 221 {
 222         int i, l;
 223         uint16_t x[8];
 224         int weight = 10;
 225
 226         cp();
 227
 228         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d#%d",
 229                           &x[0], &x[1], &x[2], &x[3], &l, &weight) >= 5) {
 230                 if(l < 0 || l > 32)
 231                         return false;
 232
 233                 subnet->type = SUBNET_IPV4;
 234                 subnet->net.ipv4.prefixlength = l;
 235                 subnet->weight = weight;
 236
 237                 for(i = 0; i < 4; i++) {
 238                         if(x[i] > 255)
 239                                 return false;
 240                         subnet->net.ipv4.address.x[i] = x[i];
 241                 }
 242
 243                 return true;
 244         }
 245
 246         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d",
 247                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
 248                           &l, &weight) >= 9) {
 249                 if(l < 0 || l > 128)
 250                         return false;
 251
 252                 subnet->type = SUBNET_IPV6;
 253                 subnet->net.ipv6.prefixlength = l;
 254                 subnet->weight = weight;
 255
 256                 for(i = 0; i < 8; i++)
 257                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 258
 259                 return true;
 260         }
 261
 262         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu#%d", &x[0], &x[1], &x[2], &x[3], &weight) >= 4) {
 263                 subnet->type = SUBNET_IPV4;
 264                 subnet->net.ipv4.prefixlength = 32;
 265                 subnet->weight = weight;
 266
 267                 for(i = 0; i < 4; i++) {
 268                         if(x[i] > 255)
 269                                 return false;
 270                         subnet->net.ipv4.address.x[i] = x[i];
 271                 }
 272
 273                 return true;
 274         }
 275
 276         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx#%d",
 277                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &weight) >= 8) {
 278                 subnet->type = SUBNET_IPV6;
 279                 subnet->net.ipv6.prefixlength = 128;
 280                 subnet->weight = weight;
 281
 282                 for(i = 0; i < 8; i++)
 283                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 284
 285                 return true;
 286         }
 287
 288         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx#%d",
 289                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &weight) >= 6) {
 290                 subnet->type = SUBNET_MAC;
 291                 subnet->weight = weight;
 292
 293                 for(i = 0; i < 6; i++)
 294                         subnet->net.mac.address.x[i] = x[i];
 295
 296                 return true;
 297         }
 298
 299         return false;
 300 }
 301
 302 bool net2str(char *netstr, int len, const subnet_t *subnet)
 303 {
 304         cp();
 305
 306         if(!netstr || !subnet) {
 307                 logger(LOG_ERR, _("net2str() was called with netstr=%p, subnet=%p!\n"), netstr, subnet);
 308                 return false;
 309         }
 310
 311         switch (subnet->type) {
 312                 case SUBNET_MAC:
 313                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx#%d",
 314                                          subnet->net.mac.address.x[0],
 315                                          subnet->net.mac.address.x[1],
 316                                          subnet->net.mac.address.x[2],
 317                                          subnet->net.mac.address.x[3],
 318                                          subnet->net.mac.address.x[4],
 319                                          subnet->net.mac.address.x[5],
 320                                          subnet->weight);
 321                         break;
 322
 323                 case SUBNET_IPV4:
 324                         snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d#%d",
 325                                          subnet->net.ipv4.address.x[0],
 326                                          subnet->net.ipv4.address.x[1],
 327                                          subnet->net.ipv4.address.x[2],
 328                                          subnet->net.ipv4.address.x[3],
 329                                          subnet->net.ipv4.prefixlength,
 330                                          subnet->weight);
 331                         break;
 332
 333                 case SUBNET_IPV6:
 334                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d",
 335                                          ntohs(subnet->net.ipv6.address.x[0]),
 336                                          ntohs(subnet->net.ipv6.address.x[1]),
 337                                          ntohs(subnet->net.ipv6.address.x[2]),
 338                                          ntohs(subnet->net.ipv6.address.x[3]),
 339                                          ntohs(subnet->net.ipv6.address.x[4]),
 340                                          ntohs(subnet->net.ipv6.address.x[5]),
 341                                          ntohs(subnet->net.ipv6.address.x[6]),
 342                                          ntohs(subnet->net.ipv6.address.x[7]),
 343                                          subnet->net.ipv6.prefixlength,
 344                                          subnet->weight);
 345                         break;
 346
 347                 default:
 348                         logger(LOG_ERR,
 349                                    _("net2str() was called with unknown subnet type %d, exiting!"),
 350                                    subnet->type);
 351                         cp_trace();
 352                         exit(0);
 353         }
 354
 355         return true;
 356 }
 357
 358 /* Subnet lookup routines */
 359
 360 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet)
 361 {
 362         cp();
 363
 364         return avl_search(owner->subnet_tree, subnet);
 365 }
 366
 367 subnet_t *lookup_subnet_mac(const mac_t *address)
 368 {
 369         subnet_t *p, subnet = {0};
 370
 371         cp();
 372
 373         subnet.type = SUBNET_MAC;
 374         subnet.net.mac.address = *address;
 375         subnet.owner = NULL;
 376
 377         p = avl_search(subnet_tree, &subnet);
 378
 379         return p;
 380 }
 381
 382 subnet_t *lookup_subnet_ipv4(const ipv4_t *address)
 383 {
 384         subnet_t *p, *r = NULL, subnet = {0};
 385         avl_node_t *n;
 386         int i;
 387
 388         cp();
 389
 390         // Check if this address is cached
 391
 392         for(i = 0; i < 2; i++) {
 393                 if(!cache_ipv4_valid[i])
 394                         continue;
 395                 if(!memcmp(address, &cache_ipv4_address[i], sizeof *address))
 396                         return cache_ipv4_subnet[i];
 397         }
 398
 399         // Search all subnets for a matching one
 400
 401         subnet.type = SUBNET_IPV4;
 402         subnet.net.ipv4.address = *address;
 403         subnet.net.ipv4.prefixlength = 32;
 404         subnet.owner = NULL;
 405
 406         for(n = subnet_tree->head; n; n = n->next) {
 407                 p = n->data;
 408
 409                 if(!p || p->type != subnet.type)
 410                         continue;
 411
 412                 if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength)) {
 413                         r = p;
 414                         if(p->owner->status.reachable)
 415                                 break;
 416                 }
 417         }
 418
 419         // Cache the result
 420
 421         cache_ipv4_slot = !cache_ipv4_slot;
 422         memcpy(&cache_ipv4_address[cache_ipv4_slot], address, sizeof *address);
 423         cache_ipv4_subnet[cache_ipv4_slot] = r;
 424         cache_ipv4_valid[cache_ipv4_slot] = true;
 425
 426         return r;
 427 }
 428
 429 subnet_t *lookup_subnet_ipv6(const ipv6_t *address)
 430 {
 431         subnet_t *p, *r = NULL, subnet = {0};
 432         avl_node_t *n;
 433         int i;
 434
 435         cp();
 436
 437         // Check if this address is cached
 438
 439         for(i = 0; i < 2; i++) {
 440                 if(!cache_ipv6_valid[i])
 441                         continue;
 442                 if(!memcmp(address, &cache_ipv6_address[i], sizeof *address))
 443                         return cache_ipv6_subnet[i];
 444         }
 445
 446         // Search all subnets for a matching one
 447
 448         subnet.type = SUBNET_IPV6;
 449         subnet.net.ipv6.address = *address;
 450         subnet.net.ipv6.prefixlength = 128;
 451         subnet.owner = NULL;
 452
 453         for(n = subnet_tree->head; n; n = n->next) {
 454                 p = n->data;
 455
 456                 if(!p || p->type != subnet.type)
 457                         continue;
 458
 459                 if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength)) {
 460                         r = p;
 461                         if(p->owner->status.reachable)
 462                                 break;
 463                 }
 464         }
 465
 466         // Cache the result
 467
 468         cache_ipv6_slot = !cache_ipv6_slot;
 469         memcpy(&cache_ipv6_address[cache_ipv6_slot], address, sizeof *address);
 470         cache_ipv6_subnet[cache_ipv6_slot] = r;
 471         cache_ipv6_valid[cache_ipv6_slot] = true;
 472
 473         return r;
 474 }
 475
 476 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 477         avl_node_t *node;
 478         int i;
 479         char *envp[8];
 480         char netstr[MAXNETSTR + 7] = "SUBNET=";
 481         char *name, *address, *port;
 482
 483         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 484         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 485         asprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 486         asprintf(&envp[3], "NODE=%s", owner->name);
 487
 488         if(owner != myself) {
 489                 sockaddr2str(&owner->address, &address, &port);
 490                 asprintf(&envp[4], "REMOTEADDRESS=%s", address);
 491                 asprintf(&envp[5], "REMOTEPORT=%s", port);
 492                 envp[6] = netstr;
 493                 envp[7] = NULL;
 494         } else {
 495                 envp[4] = netstr;
 496                 envp[5] = NULL;
 497         }
 498
 499         name = up ? "subnet-up" : "subnet-down";
 500
 501         if(!subnet) {
 502                 for(node = owner->subnet_tree->head; node; node = node->next) {
 503                         subnet = node->data;
 504                         if(!net2str(netstr + 7, sizeof netstr - 7, subnet))
 505                                 continue;
 506                         execute_script(name, envp);
 507                 }
 508         } else {
 509                 if(net2str(netstr + 7, sizeof netstr - 7, subnet))
 510                         execute_script(name, envp);
 511         }
 512
 513         for(i = 0; i < (owner != myself ? 6 : 4); i++)
 514                 free(envp[i]);
 515
 516         if(owner != myself) {
 517                 free(address);
 518                 free(port);
 519         }
 520 }
 521
 522 void dump_subnets(void)
 523 {
 524         char netstr[MAXNETSTR];
 525         subnet_t *subnet;
 526         avl_node_t *node;
 527
 528         cp();
 529
 530         logger(LOG_DEBUG, _("Subnet list:"));
 531
 532         for(node = subnet_tree->head; node; node = node->next) {
 533                 subnet = node->data;
 534                 if(!net2str(netstr, sizeof netstr, subnet))
 535                         continue;
 536                 logger(LOG_DEBUG, _(" %s owner %s"), netstr, subnet->owner->name);
 537         }
 538
 539         logger(LOG_DEBUG, _("End of subnet list."));
 540 }