git.meshlink.io Git - meshlink/blob - src/subnet.c

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2007 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 comparison */
  41
  42 static int subnet_compare_mac(const subnet_t *a, const subnet_t *b)
  43 {
  44         int result;
  45
  46         result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  47
  48         if(result || !a->owner || !b->owner)
  49                 return result;
  50
  51         return strcmp(a->owner->name, b->owner->name);
  52 }
  53
  54 static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b)
  55 {
  56         int result;
  57
  58         result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
  59
  60         if(result)
  61                 return result;
  62
  63         result = a->net.ipv4.prefixlength - b->net.ipv4.prefixlength;
  64
  65         if(result || !a->owner || !b->owner)
  66                 return result;
  67
  68         return strcmp(a->owner->name, b->owner->name);
  69 }
  70
  71 static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b)
  72 {
  73         int result;
  74
  75         result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
  76
  77         if(result)
  78                 return result;
  79
  80         result = a->net.ipv6.prefixlength - b->net.ipv6.prefixlength;
  81
  82         if(result || !a->owner || !b->owner)
  83                 return result;
  84
  85         return strcmp(a->owner->name, b->owner->name);
  86 }
  87
  88 int subnet_compare(const subnet_t *a, const subnet_t *b)
  89 {
  90         int result;
  91
  92         result = a->type - b->type;
  93
  94         if(result)
  95                 return result;
  96
  97         switch (a->type) {
  98         case SUBNET_MAC:
  99                 return subnet_compare_mac(a, b);
 100         case SUBNET_IPV4:
 101                 return subnet_compare_ipv4(a, b);
 102         case SUBNET_IPV6:
 103                 return subnet_compare_ipv6(a, b);
 104         default:
 105                 logger(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, exitting!"),
 106                            a->type);
 107                 cp_trace();
 108                 exit(0);
 109         }
 110
 111         return 0;
 112 }
 113
 114 /* Initialising trees */
 115
 116 void init_subnets(void)
 117 {
 118         cp();
 119
 120         subnet_tree = avl_alloc_tree((avl_compare_t) subnet_compare, (avl_action_t) free_subnet);
 121 }
 122
 123 void exit_subnets(void)
 124 {
 125         cp();
 126
 127         avl_delete_tree(subnet_tree);
 128 }
 129
 130 avl_tree_t *new_subnet_tree(void)
 131 {
 132         cp();
 133
 134         return avl_alloc_tree((avl_compare_t) subnet_compare, NULL);
 135 }
 136
 137 void free_subnet_tree(avl_tree_t *subnet_tree)
 138 {
 139         cp();
 140
 141         avl_delete_tree(subnet_tree);
 142 }
 143
 144 /* Allocating and freeing space for subnets */
 145
 146 subnet_t *new_subnet(void)
 147 {
 148         cp();
 149
 150         return xmalloc_and_zero(sizeof(subnet_t));
 151 }
 152
 153 void free_subnet(subnet_t *subnet)
 154 {
 155         cp();
 156
 157         free(subnet);
 158 }
 159
 160 /* Adding and removing subnets */
 161
 162 void subnet_add(node_t *n, subnet_t *subnet)
 163 {
 164         cp();
 165
 166         subnet->owner = n;
 167
 168         avl_insert(subnet_tree, subnet);
 169         avl_insert(n->subnet_tree, subnet);
 170 }
 171
 172 void subnet_del(node_t *n, subnet_t *subnet)
 173 {
 174         cp();
 175
 176         avl_delete(n->subnet_tree, subnet);
 177         avl_delete(subnet_tree, subnet);
 178 }
 179
 180 /* Ascii representation of subnets */
 181
 182 bool str2net(subnet_t *subnet, const char *subnetstr)
 183 {
 184         int i, l;
 185         uint16_t x[8];
 186
 187         cp();
 188
 189         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d",
 190                           &x[0], &x[1], &x[2], &x[3], &l) == 5) {
 191                 if(l < 0 || l > 32)
 192                         return false;
 193
 194                 subnet->type = SUBNET_IPV4;
 195                 subnet->net.ipv4.prefixlength = l;
 196
 197                 for(i = 0; i < 4; i++) {
 198                         if(x[i] > 255)
 199                                 return false;
 200                         subnet->net.ipv4.address.x[i] = x[i];
 201                 }
 202
 203                 return true;
 204         }
 205
 206         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 207                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
 208                           &l) == 9) {
 209                 if(l < 0 || l > 128)
 210                         return false;
 211
 212                 subnet->type = SUBNET_IPV6;
 213                 subnet->net.ipv6.prefixlength = l;
 214
 215                 for(i = 0; i < 8; i++)
 216                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 217
 218                 return true;
 219         }
 220
 221         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu", &x[0], &x[1], &x[2], &x[3]) == 4) {
 222                 subnet->type = SUBNET_IPV4;
 223                 subnet->net.ipv4.prefixlength = 32;
 224
 225                 for(i = 0; i < 4; i++) {
 226                         if(x[i] > 255)
 227                                 return false;
 228                         subnet->net.ipv4.address.x[i] = x[i];
 229                 }
 230
 231                 return true;
 232         }
 233
 234         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
 235                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7]) == 8) {
 236                 subnet->type = SUBNET_IPV6;
 237                 subnet->net.ipv6.prefixlength = 128;
 238
 239                 for(i = 0; i < 8; i++)
 240                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 241
 242                 return true;
 243         }
 244
 245         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 246                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5]) == 6) {
 247                 subnet->type = SUBNET_MAC;
 248
 249                 for(i = 0; i < 6; i++)
 250                         subnet->net.mac.address.x[i] = x[i];
 251
 252                 return true;
 253         }
 254
 255         return false;
 256 }
 257
 258 bool net2str(char *netstr, int len, const subnet_t *subnet)
 259 {
 260         cp();
 261
 262         if(!netstr || !subnet) {
 263                 logger(LOG_ERR, _("net2str() was called with netstr=%p, subnet=%p!\n"), netstr, subnet);
 264                 return false;
 265         }
 266
 267         switch (subnet->type) {
 268                 case SUBNET_MAC:
 269                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx",
 270                                          subnet->net.mac.address.x[0],
 271                                          subnet->net.mac.address.x[1],
 272                                          subnet->net.mac.address.x[2],
 273                                          subnet->net.mac.address.x[3],
 274                                          subnet->net.mac.address.x[4], subnet->net.mac.address.x[5]);
 275                         break;
 276
 277                 case SUBNET_IPV4:
 278                         snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d",
 279                                          subnet->net.ipv4.address.x[0],
 280                                          subnet->net.ipv4.address.x[1],
 281                                          subnet->net.ipv4.address.x[2],
 282                                          subnet->net.ipv4.address.x[3], subnet->net.ipv4.prefixlength);
 283                         break;
 284
 285                 case SUBNET_IPV6:
 286                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 287                                          ntohs(subnet->net.ipv6.address.x[0]),
 288                                          ntohs(subnet->net.ipv6.address.x[1]),
 289                                          ntohs(subnet->net.ipv6.address.x[2]),
 290                                          ntohs(subnet->net.ipv6.address.x[3]),
 291                                          ntohs(subnet->net.ipv6.address.x[4]),
 292                                          ntohs(subnet->net.ipv6.address.x[5]),
 293                                          ntohs(subnet->net.ipv6.address.x[6]),
 294                                          ntohs(subnet->net.ipv6.address.x[7]),
 295                                          subnet->net.ipv6.prefixlength);
 296                         break;
 297
 298                 default:
 299                         logger(LOG_ERR,
 300                                    _("net2str() was called with unknown subnet type %d, exiting!"),
 301                                    subnet->type);
 302                         cp_trace();
 303                         exit(0);
 304         }
 305
 306         return true;
 307 }
 308
 309 /* Subnet lookup routines */
 310
 311 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet)
 312 {
 313         cp();
 314
 315         return avl_search(owner->subnet_tree, subnet);
 316 }
 317
 318 subnet_t *lookup_subnet_mac(const mac_t *address)
 319 {
 320         subnet_t *p, subnet = {0};
 321
 322         cp();
 323
 324         subnet.type = SUBNET_MAC;
 325         subnet.net.mac.address = *address;
 326         subnet.owner = NULL;
 327
 328         p = avl_search(subnet_tree, &subnet);
 329
 330         return p;
 331 }
 332
 333 subnet_t *lookup_subnet_ipv4(const ipv4_t *address)
 334 {
 335         subnet_t *p, subnet = {0};
 336
 337         cp();
 338
 339         subnet.type = SUBNET_IPV4;
 340         subnet.net.ipv4.address = *address;
 341         subnet.net.ipv4.prefixlength = 32;
 342         subnet.owner = NULL;
 343
 344         do {
 345                 /* Go find subnet */
 346
 347                 p = avl_search_closest_smaller(subnet_tree, &subnet);
 348
 349                 /* Check if the found subnet REALLY matches */
 350
 351                 if(p) {
 352                         if(p->type != SUBNET_IPV4) {
 353                                 p = NULL;
 354                                 break;
 355                         }
 356
 357                         if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength))
 358                                 break;
 359                         else {
 360                                 /* Otherwise, see if there is a bigger enclosing subnet */
 361
 362                                 subnet.net.ipv4.prefixlength = p->net.ipv4.prefixlength - 1;
 363                                 if(subnet.net.ipv4.prefixlength < 0 || subnet.net.ipv4.prefixlength > 32)
 364                                         return NULL;
 365                                 maskcpy(&subnet.net.ipv4.address, &p->net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof(ipv4_t));
 366                         }
 367                 }
 368         } while(p);
 369
 370         return p;
 371 }
 372
 373 subnet_t *lookup_subnet_ipv6(const ipv6_t *address)
 374 {
 375         subnet_t *p, subnet = {0};
 376
 377         cp();
 378
 379         subnet.type = SUBNET_IPV6;
 380         subnet.net.ipv6.address = *address;
 381         subnet.net.ipv6.prefixlength = 128;
 382         subnet.owner = NULL;
 383
 384         do {
 385                 /* Go find subnet */
 386
 387                 p = avl_search_closest_smaller(subnet_tree, &subnet);
 388
 389                 /* Check if the found subnet REALLY matches */
 390
 391                 if(p) {
 392                         if(p->type != SUBNET_IPV6)
 393                                 return NULL;
 394
 395                         if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength))
 396                                 break;
 397                         else {
 398                                 /* Otherwise, see if there is a bigger enclosing subnet */
 399
 400                                 subnet.net.ipv6.prefixlength = p->net.ipv6.prefixlength - 1;
 401                                 if(subnet.net.ipv6.prefixlength < 0 || subnet.net.ipv6.prefixlength > 128)
 402                                         return NULL;
 403                                 maskcpy(&subnet.net.ipv6.address, &p->net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof(ipv6_t));
 404                         }
 405                 }
 406         } while(p);
 407
 408         return p;
 409 }
 410
 411 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 412         avl_node_t *node;
 413         int i;
 414         char *envp[8];
 415         char netstr[MAXNETSTR + 7] = "SUBNET=";
 416         char *name, *address, *port;
 417
 418         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 419         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 420         asprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 421         asprintf(&envp[3], "NODE=%s", owner->name);
 422
 423         if(owner != myself) {
 424                 sockaddr2str(&owner->address, &address, &port);
 425                 asprintf(&envp[4], "REMOTEADDRESS=%s", address);
 426                 asprintf(&envp[5], "REMOTEPORT=%s", port);
 427                 envp[6] = netstr;
 428                 envp[7] = NULL;
 429         } else {
 430                 envp[4] = netstr;
 431                 envp[5] = NULL;
 432         }
 433
 434         name = up ? "subnet-up" : "subnet-down";
 435
 436         if(!subnet) {
 437                 for(node = owner->subnet_tree->head; node; node = node->next) {
 438                         subnet = node->data;
 439                         if(!net2str(netstr + 7, sizeof netstr - 7, subnet))
 440                                 continue;
 441                         execute_script(name, envp);
 442                 }
 443         } else {
 444                 if(net2str(netstr + 7, sizeof netstr - 7, subnet))
 445                         execute_script(name, envp);
 446         }
 447
 448         for(i = 0; i < (owner != myself ? 6 : 4); i++)
 449                 free(envp[i]);
 450
 451         if(owner != myself) {
 452                 free(address);
 453                 free(port);
 454         }
 455 }
 456
 457 void dump_subnets(void)
 458 {
 459         char netstr[MAXNETSTR];
 460         subnet_t *subnet;
 461         avl_node_t *node;
 462
 463         cp();
 464
 465         logger(LOG_DEBUG, _("Subnet list:"));
 466
 467         for(node = subnet_tree->head; node; node = node->next) {
 468                 subnet = node->data;
 469                 if(!net2str(netstr, sizeof netstr, subnet))
 470                         continue;
 471                 logger(LOG_DEBUG, _(" %s owner %s"), netstr, subnet->owner->name);
 472         }
 473
 474         logger(LOG_DEBUG, _("End of subnet list."));
 475 }