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

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2003 Guus Sliepen <guus@sliepen.eu.org>,
   4                   2000-2003 Ivo Timmermans <ivo@o2w.nl>
   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: subnet.c,v 1.1.2.48 2003/07/24 12:08:16 guus Exp $
  21 */
  22
  23 #include "system.h"
  24
  25 #include "avl_tree.h"
  26 #include "logger.h"
  27 #include "net.h"
  28 #include "netutl.h"
  29 #include "node.h"
  30 #include "subnet.h"
  31 #include "utils.h"
  32 #include "xalloc.h"
  33
  34 /* lists type of subnet */
  35
  36 avl_tree_t *subnet_tree;
  37
  38 /* Subnet comparison */
  39
  40 static int subnet_compare_mac(const subnet_t *a, const subnet_t *b)
  41 {
  42         int result;
  43
  44         result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  45
  46         if(result || !a->owner || !b->owner)
  47                 return result;
  48
  49         return strcmp(a->owner->name, b->owner->name);
  50 }
  51
  52 static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b)
  53 {
  54         int result;
  55
  56         result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
  57
  58         if(result)
  59                 return result;
  60
  61         result = a->net.ipv4.prefixlength - b->net.ipv4.prefixlength;
  62
  63         if(result || !a->owner || !b->owner)
  64                 return result;
  65
  66         return strcmp(a->owner->name, b->owner->name);
  67 }
  68
  69 static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b)
  70 {
  71         int result;
  72
  73         result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
  74
  75         if(result)
  76                 return result;
  77
  78         result = a->net.ipv6.prefixlength - b->net.ipv6.prefixlength;
  79
  80         if(result || !a->owner || !b->owner)
  81                 return result;
  82
  83         return strcmp(a->owner->name, b->owner->name);
  84 }
  85
  86 static int subnet_compare(const subnet_t *a, const subnet_t *b)
  87 {
  88         int result;
  89
  90         result = a->type - b->type;
  91
  92         if(result)
  93                 return result;
  94
  95         switch (a->type) {
  96         case SUBNET_MAC:
  97                 return subnet_compare_mac(a, b);
  98         case SUBNET_IPV4:
  99                 return subnet_compare_ipv4(a, b);
 100         case SUBNET_IPV6:
 101                 return subnet_compare_ipv6(a, b);
 102         default:
 103                 logger(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, exitting!"),
 104                            a->type);
 105                 cp_trace();
 106                 exit(0);
 107         }
 108
 109         return 0;
 110 }
 111
 112 /* Initialising trees */
 113
 114 void init_subnets(void)
 115 {
 116         cp();
 117
 118         subnet_tree = avl_alloc_tree((avl_compare_t) subnet_compare, (avl_action_t) free_subnet);
 119 }
 120
 121 void exit_subnets(void)
 122 {
 123         cp();
 124
 125         avl_delete_tree(subnet_tree);
 126 }
 127
 128 avl_tree_t *new_subnet_tree(void)
 129 {
 130         cp();
 131
 132         return avl_alloc_tree((avl_compare_t) subnet_compare, NULL);
 133 }
 134
 135 void free_subnet_tree(avl_tree_t *subnet_tree)
 136 {
 137         cp();
 138
 139         avl_delete_tree(subnet_tree);
 140 }
 141
 142 /* Allocating and freeing space for subnets */
 143
 144 subnet_t *new_subnet(void)
 145 {
 146         cp();
 147
 148         return (subnet_t *) xmalloc_and_zero(sizeof(subnet_t));
 149 }
 150
 151 void free_subnet(subnet_t *subnet)
 152 {
 153         cp();
 154
 155         free(subnet);
 156 }
 157
 158 /* Adding and removing subnets */
 159
 160 void subnet_add(node_t *n, subnet_t *subnet)
 161 {
 162         cp();
 163
 164         subnet->owner = n;
 165
 166         avl_insert(subnet_tree, subnet);
 167         avl_insert(n->subnet_tree, subnet);
 168 }
 169
 170 void subnet_del(node_t *n, subnet_t *subnet)
 171 {
 172         cp();
 173
 174         avl_delete(n->subnet_tree, subnet);
 175         avl_delete(subnet_tree, subnet);
 176 }
 177
 178 /* Ascii representation of subnets */
 179
 180 subnet_t *str2net(const char *subnetstr)
 181 {
 182         int i, l;
 183         subnet_t *subnet;
 184         uint16_t x[8];
 185
 186         cp();
 187
 188         subnet = new_subnet();
 189
 190         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d",
 191                           &x[0], &x[1], &x[2], &x[3], &l) == 5) {
 192                 subnet->type = SUBNET_IPV4;
 193                 subnet->net.ipv4.prefixlength = l;
 194
 195                 for(i = 0; i < 4; i++)
 196                         subnet->net.ipv4.address.x[i] = x[i];
 197
 198                 return subnet;
 199         }
 200
 201         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 202                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
 203                           &l) == 9) {
 204                 subnet->type = SUBNET_IPV6;
 205                 subnet->net.ipv6.prefixlength = l;
 206
 207                 for(i = 0; i < 8; i++)
 208                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 209
 210                 return subnet;
 211         }
 212
 213         if(sscanf(subnetstr, "%hu.%hu.%hu.%hu", &x[0], &x[1], &x[2], &x[3]) == 4) {
 214                 subnet->type = SUBNET_IPV4;
 215                 subnet->net.ipv4.prefixlength = 32;
 216
 217                 for(i = 0; i < 4; i++)
 218                         subnet->net.ipv4.address.x[i] = x[i];
 219
 220                 return subnet;
 221         }
 222
 223         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
 224                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7]) == 8) {
 225                 subnet->type = SUBNET_IPV6;
 226                 subnet->net.ipv6.prefixlength = 128;
 227
 228                 for(i = 0; i < 8; i++)
 229                         subnet->net.ipv6.address.x[i] = htons(x[i]);
 230
 231                 return subnet;
 232         }
 233
 234         if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 235                           &x[0], &x[1], &x[2], &x[3], &x[4], &x[5]) == 6) {
 236                 subnet->type = SUBNET_MAC;
 237
 238                 for(i = 0; i < 6; i++)
 239                         subnet->net.mac.address.x[i] = x[i];
 240
 241                 return subnet;
 242         }
 243
 244         free(subnet);
 245
 246         return NULL;
 247 }
 248
 249 char *net2str(const subnet_t *subnet)
 250 {
 251         char *netstr;
 252
 253         cp();
 254
 255         switch (subnet->type) {
 256                 case SUBNET_MAC:
 257                         asprintf(&netstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 258                                          subnet->net.mac.address.x[0],
 259                                          subnet->net.mac.address.x[1],
 260                                          subnet->net.mac.address.x[2],
 261                                          subnet->net.mac.address.x[3],
 262                                          subnet->net.mac.address.x[4], subnet->net.mac.address.x[5]);
 263                         break;
 264
 265                 case SUBNET_IPV4:
 266                         asprintf(&netstr, "%hu.%hu.%hu.%hu/%d",
 267                                          subnet->net.ipv4.address.x[0],
 268                                          subnet->net.ipv4.address.x[1],
 269                                          subnet->net.ipv4.address.x[2],
 270                                          subnet->net.ipv4.address.x[3], subnet->net.ipv4.prefixlength);
 271                         break;
 272
 273                 case SUBNET_IPV6:
 274                         asprintf(&netstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 275                                          ntohs(subnet->net.ipv6.address.x[0]),
 276                                          ntohs(subnet->net.ipv6.address.x[1]),
 277                                          ntohs(subnet->net.ipv6.address.x[2]),
 278                                          ntohs(subnet->net.ipv6.address.x[3]),
 279                                          ntohs(subnet->net.ipv6.address.x[4]),
 280                                          ntohs(subnet->net.ipv6.address.x[5]),
 281                                          ntohs(subnet->net.ipv6.address.x[6]),
 282                                          ntohs(subnet->net.ipv6.address.x[7]),
 283                                          subnet->net.ipv6.prefixlength);
 284                         break;
 285
 286                 default:
 287                         logger(LOG_ERR,
 288                                    _("net2str() was called with unknown subnet type %d, exiting!"),
 289                                    subnet->type);
 290                         cp_trace();
 291                         exit(0);
 292         }
 293
 294         return netstr;
 295 }
 296
 297 /* Subnet lookup routines */
 298
 299 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet)
 300 {
 301         cp();
 302
 303         return avl_search(owner->subnet_tree, subnet);
 304 }
 305
 306 subnet_t *lookup_subnet_mac(const mac_t *address)
 307 {
 308         subnet_t subnet = {
 309                 .type = SUBNET_MAC,
 310                 .net.mac.address = *address,
 311                 .owner = NULL
 312         };
 313         subnet_t *p;
 314
 315         cp();
 316
 317         p = (subnet_t *) avl_search(subnet_tree, &subnet);
 318
 319         return p;
 320 }
 321
 322 subnet_t *lookup_subnet_ipv4(const ipv4_t *address)
 323 {
 324         subnet_t subnet = {
 325                 .type = SUBNET_IPV4,
 326                 .net.ipv4.address = *address,
 327                 .net.ipv4.prefixlength = 32,
 328                 .owner = NULL
 329         };
 330         subnet_t *p;
 331
 332         cp();
 333
 334         do {
 335                 /* Go find subnet */
 336
 337                 p = (subnet_t *) avl_search_closest_smaller(subnet_tree, &subnet);
 338
 339                 /* Check if the found subnet REALLY matches */
 340
 341                 if(p) {
 342                         if(p->type != SUBNET_IPV4) {
 343                                 p = NULL;
 344                                 break;
 345                         }
 346
 347                         if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength, sizeof(ipv4_t)))
 348                                 break;
 349                         else {
 350                                 /* Otherwise, see if there is a bigger enclosing subnet */
 351
 352                                 subnet.net.ipv4.prefixlength = p->net.ipv4.prefixlength - 1;
 353                                 maskcpy(&subnet.net.ipv4.address, &p->net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof(ipv4_t));
 354                         }
 355                 }
 356         } while(p);
 357
 358         return p;
 359 }
 360
 361 subnet_t *lookup_subnet_ipv6(const ipv6_t *address)
 362 {
 363         subnet_t subnet = {
 364                 .type = SUBNET_IPV6,
 365                 .net.ipv6.address = *address,
 366                 .net.ipv6.prefixlength = 128,
 367                 .owner = NULL
 368         };
 369         subnet_t *p;
 370
 371         cp();
 372
 373         do {
 374                 /* Go find subnet */
 375
 376                 p = (subnet_t *) avl_search_closest_smaller(subnet_tree, &subnet);
 377
 378                 /* Check if the found subnet REALLY matches */
 379
 380                 if(p) {
 381                         if(p->type != SUBNET_IPV6)
 382                                 return NULL;
 383
 384                         if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength, sizeof(ipv6_t)))
 385                                 break;
 386                         else {
 387                                 /* Otherwise, see if there is a bigger enclosing subnet */
 388
 389                                 subnet.net.ipv6.prefixlength = p->net.ipv6.prefixlength - 1;
 390                                 maskcpy(&subnet.net.ipv6.address, &p->net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof(ipv6_t));
 391                         }
 392                 }
 393         } while(p);
 394
 395         return p;
 396 }
 397
 398 void dump_subnets(void)
 399 {
 400         char *netstr;
 401         subnet_t *subnet;
 402         avl_node_t *node;
 403
 404         cp();
 405
 406         logger(LOG_DEBUG, _("Subnet list:"));
 407
 408         for(node = subnet_tree->head; node; node = node->next) {
 409                 subnet = (subnet_t *) node->data;
 410                 netstr = net2str(subnet);
 411                 logger(LOG_DEBUG, _(" %s owner %s"), netstr, subnet->owner->name);
 412                 free(netstr);
 413         }
 414
 415         logger(LOG_DEBUG, _("End of subnet list."));
 416 }