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

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2004 Guus Sliepen <guus@tinc-vpn.org>,
   4                   2000-2004 Ivo Timmermans <ivo@tinc-vpn.org>
   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                 subnet->type = SUBNET_IPV4;
 192                 subnet->net.ipv4.prefixlength = l;
 193
 194                 for(i = 0; i < 4; i++)
 195                         subnet->net.ipv4.address.x[i] = x[i];
 196
 197                 return true;
 198         }
 199
 200         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 201                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
 202                           &l) == 9) {
 203                 subnet->type = SUBNET_IPV6;
 204                 subnet->net.ipv6.prefixlength = l;
 205
 206                 for(i = 0; i < 8; i++)
 207                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 208
 209                 return true;
 210         }
 211
 212         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu", &x[0], &x[1], &x[2], &x[3]) == 4) {
 213                 subnet->type = SUBNET_IPV4;
 214                 subnet->net.ipv4.prefixlength = 32;
 215
 216                 for(i = 0; i < 4; i++)
 217                         subnet->net.ipv4.address.x[i] = x[i];
 218
 219                 return true;
 220         }
 221
 222         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
 223                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7]) == 8) {
 224                 subnet->type = SUBNET_IPV6;
 225                 subnet->net.ipv6.prefixlength = 128;
 226
 227                 for(i = 0; i < 8; i++)
 228                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 229
 230                 return true;
 231         }
 232
 233         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 234                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5]) == 6) {
 235                 subnet->type = SUBNET_MAC;
 236
 237                 for(i = 0; i < 6; i++)
 238                         subnet->net.mac.address.x[i] = x[i];
 239
 240                 return true;
 241         }
 242
 243         return false;
 244 }
 245
 246 bool net2str(char *netstr, int len, const subnet_t *subnet)
 247 {
 248         cp();
 249
 250         switch (subnet->type) {
 251                 case SUBNET_MAC:
 252                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx",
 253                                          subnet->net.mac.address.x[0],
 254                                          subnet->net.mac.address.x[1],
 255                                          subnet->net.mac.address.x[2],
 256                                          subnet->net.mac.address.x[3],
 257                                          subnet->net.mac.address.x[4], subnet->net.mac.address.x[5]);
 258                         break;
 259
 260                 case SUBNET_IPV4:
 261                         snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d",
 262                                          subnet->net.ipv4.address.x[0],
 263                                          subnet->net.ipv4.address.x[1],
 264                                          subnet->net.ipv4.address.x[2],
 265                                          subnet->net.ipv4.address.x[3], subnet->net.ipv4.prefixlength);
 266                         break;
 267
 268                 case SUBNET_IPV6:
 269                         snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 270                                          ntohs(subnet->net.ipv6.address.x[0]),
 271                                          ntohs(subnet->net.ipv6.address.x[1]),
 272                                          ntohs(subnet->net.ipv6.address.x[2]),
 273                                          ntohs(subnet->net.ipv6.address.x[3]),
 274                                          ntohs(subnet->net.ipv6.address.x[4]),
 275                                          ntohs(subnet->net.ipv6.address.x[5]),
 276                                          ntohs(subnet->net.ipv6.address.x[6]),
 277                                          ntohs(subnet->net.ipv6.address.x[7]),
 278                                          subnet->net.ipv6.prefixlength);
 279                         break;
 280
 281                 default:
 282                         logger(LOG_ERR,
 283                                    _("net2str() was called with unknown subnet type %d, exiting!"),
 284                                    subnet->type);
 285                         cp_trace();
 286                         exit(0);
 287         }
 288
 289         return true;
 290 }
 291
 292 /* Subnet lookup routines */
 293
 294 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet)
 295 {
 296         cp();
 297
 298         return avl_search(owner->subnet_tree, subnet);
 299 }
 300
 301 subnet_t *lookup_subnet_mac(const mac_t *address)
 302 {
 303         subnet_t *p, subnet = {0};
 304
 305         cp();
 306
 307         subnet.type = SUBNET_MAC;
 308         subnet.net.mac.address = *address;
 309         subnet.owner = NULL;
 310
 311         p = avl_search(subnet_tree, &subnet);
 312
 313         return p;
 314 }
 315
 316 subnet_t *lookup_subnet_ipv4(const ipv4_t *address)
 317 {
 318         subnet_t *p, subnet = {0};
 319
 320         cp();
 321
 322         subnet.type = SUBNET_IPV4;
 323         subnet.net.ipv4.address = *address;
 324         subnet.net.ipv4.prefixlength = 32;
 325         subnet.owner = NULL;
 326
 327         do {
 328                 /* Go find subnet */
 329
 330                 p = avl_search_closest_smaller(subnet_tree, &subnet);
 331
 332                 /* Check if the found subnet REALLY matches */
 333
 334                 if(p) {
 335                         if(p->type != SUBNET_IPV4) {
 336                                 p = NULL;
 337                                 break;
 338                         }
 339
 340                         if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength, sizeof(ipv4_t)))
 341                                 break;
 342                         else {
 343                                 /* Otherwise, see if there is a bigger enclosing subnet */
 344
 345                                 subnet.net.ipv4.prefixlength = p->net.ipv4.prefixlength - 1;
 346                                 maskcpy(&subnet.net.ipv4.address, &p->net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof(ipv4_t));
 347                         }
 348                 }
 349         } while(p);
 350
 351         return p;
 352 }
 353
 354 subnet_t *lookup_subnet_ipv6(const ipv6_t *address)
 355 {
 356         subnet_t *p, subnet = {0};
 357
 358         cp();
 359
 360         subnet.type = SUBNET_IPV6;
 361         subnet.net.ipv6.address = *address;
 362         subnet.net.ipv6.prefixlength = 128;
 363         subnet.owner = NULL;
 364
 365         do {
 366                 /* Go find subnet */
 367
 368                 p = avl_search_closest_smaller(subnet_tree, &subnet);
 369
 370                 /* Check if the found subnet REALLY matches */
 371
 372                 if(p) {
 373                         if(p->type != SUBNET_IPV6)
 374                                 return NULL;
 375
 376                         if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength, sizeof(ipv6_t)))
 377                                 break;
 378                         else {
 379                                 /* Otherwise, see if there is a bigger enclosing subnet */
 380
 381                                 subnet.net.ipv6.prefixlength = p->net.ipv6.prefixlength - 1;
 382                                 maskcpy(&subnet.net.ipv6.address, &p->net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof(ipv6_t));
 383                         }
 384                 }
 385         } while(p);
 386
 387         return p;
 388 }
 389
 390 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 391         avl_node_t *node;
 392         int i;
 393         char *envp[8];
 394         char netstr[MAXNETSTR + 7] = "SUBNET=";
 395         char *name, *address, *port;
 396
 397         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 398         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 399         asprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 400         asprintf(&envp[3], "NODE=%s", owner->name);
 401         if(owner != myself) {
 402                 sockaddr2str(&owner->address, &address, &port);
 403                 asprintf(&envp[4], "REMOTEADDRESS=%s", address);
 404                 asprintf(&envp[5], "REMOTEPORT=%s", port);
 405                 envp[6] = netstr;
 406                 envp[7] = NULL;
 407         } else {
 408                 envp[4] = netstr;
 409                 envp[5] = NULL;
 410         }
 411
 412         name = up ? "subnet-up" : "subnet-down";
 413
 414         if(!subnet) {
 415                 for(node = owner->subnet_tree->head; node; node = node->next) {
 416                         subnet = node->data;
 417                         if(!net2str(netstr + 7, sizeof netstr - 7, subnet))
 418                                 continue;
 419                         execute_script(name, envp);
 420                 }
 421         } else {
 422                 if(net2str(netstr + 7, sizeof netstr - 7, subnet))
 423                         execute_script(name, envp);
 424         }
 425
 426         net2str(netstr, sizeof netstr, subnet);
 427         envp[6] = envp[7] = NULL;
 428
 429         for(i = 0; i < (owner != myself ? 6 : 4); i++)
 430                 free(envp[i]);
 431
 432         free(address);
 433         free(port);
 434 }
 435
 436 void dump_subnets(void)
 437 {
 438         char netstr[MAXNETSTR];
 439         subnet_t *subnet;
 440         avl_node_t *node;
 441
 442         cp();
 443
 444         logger(LOG_DEBUG, _("Subnet list:"));
 445
 446         for(node = subnet_tree->head; node; node = node->next) {
 447                 subnet = node->data;
 448                 if(!net2str(netstr, sizeof netstr, subnet))
 449                         continue;
 450                 logger(LOG_DEBUG, _(" %s owner %s"), netstr, subnet->owner->name);
 451         }
 452
 453         logger(LOG_DEBUG, _("End of subnet list."));
 454 }