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

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2002 Guus Sliepen <guus@sliepen.warande.net>,
   4                   2000-2002 Ivo Timmermans <itimmermans@bigfoot.com>
   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 1.1.2.33 2002/03/12 14:20:44 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <stdio.h>
  26 #include <syslog.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <fcntl.h>
  30 #include <netdb.h>
  31 #include <netinet/in.h>
  32
  33 #include <utils.h>
  34 #include <xalloc.h>
  35 #include <avl_tree.h>
  36
  37 #include "conf.h"
  38 #include "net.h"
  39 #include "node.h"
  40 #include "subnet.h"
  41 #include "netutl.h"
  42
  43 #include "system.h"
  44
  45 /* lists type of subnet */
  46
  47 avl_tree_t *subnet_tree;
  48
  49 /* Subnet comparison */
  50
  51 int subnet_compare_mac(subnet_t *a, subnet_t *b)
  52 {
  53 cp
  54   return memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  55 }
  56
  57 int subnet_compare_ipv4(subnet_t *a, subnet_t *b)
  58 {
  59   int result;
  60 cp
  61   result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
  62
  63   if(result)
  64     return result;
  65
  66   return a->net.ipv4.masklength - b->net.ipv4.masklength;
  67 }
  68
  69 int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
  70 {
  71   int result;
  72 cp
  73   result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
  74
  75   if(result)
  76     return result;
  77
  78   return a->net.ipv6.masklength - b->net.ipv6.masklength;
  79 }
  80
  81 int subnet_compare(subnet_t *a, subnet_t *b)
  82 {
  83   int result;
  84 cp
  85   result = a->type - b->type;
  86
  87   if(result)
  88     return result;
  89
  90   switch(a->type)
  91     {
  92       case SUBNET_MAC:
  93         return subnet_compare_mac(a, b);
  94       case SUBNET_IPV4:
  95         return subnet_compare_ipv4(a, b);
  96       case SUBNET_IPV6:
  97         return subnet_compare_ipv6(a, b);
  98       default:
  99         syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, exitting!"), a->type);
 100         cp_trace();
 101         exit(0);
 102     }
 103
 104   return 0;
 105 }
 106
 107 /* Initialising trees */
 108
 109 void init_subnets(void)
 110 {
 111 cp
 112   subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
 113 cp
 114 }
 115
 116 void exit_subnets(void)
 117 {
 118 cp
 119   avl_delete_tree(subnet_tree);
 120 cp
 121 }
 122
 123 avl_tree_t *new_subnet_tree(void)
 124 {
 125 cp
 126   return avl_alloc_tree((avl_compare_t)subnet_compare, NULL);
 127 cp
 128 }
 129
 130 void free_subnet_tree(avl_tree_t *subnet_tree)
 131 {
 132 cp
 133   avl_delete_tree(subnet_tree);
 134 cp
 135 }
 136
 137 /* Allocating and freeing space for subnets */
 138
 139 subnet_t *new_subnet(void)
 140 {
 141 cp
 142   return (subnet_t *)xmalloc(sizeof(subnet_t));
 143 }
 144
 145 void free_subnet(subnet_t *subnet)
 146 {
 147 cp
 148   free(subnet);
 149 }
 150
 151 /* Adding and removing subnets */
 152
 153 void subnet_add(node_t *n, subnet_t *subnet)
 154 {
 155 cp
 156   subnet->owner = n;
 157
 158   avl_insert(subnet_tree, subnet);
 159 cp
 160   avl_insert(n->subnet_tree, subnet);
 161 cp
 162 }
 163
 164 void subnet_del(node_t *n, subnet_t *subnet)
 165 {
 166 cp
 167   avl_delete(n->subnet_tree, subnet);
 168 cp
 169   avl_delete(subnet_tree, subnet);
 170 cp
 171 }
 172
 173 /* Ascii representation of subnets */
 174
 175 subnet_t *str2net(char *subnetstr)
 176 {
 177   int i, l;
 178   subnet_t *subnet;
 179   unsigned short int x[8];
 180 cp
 181   subnet = new_subnet();
 182 cp
 183   if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d",
 184               &x[0], &x[1], &x[2], &x[3],
 185               &l) == 5)
 186     {
 187       subnet->type = SUBNET_IPV4;
 188       subnet->net.ipv4.masklength = l;
 189       for(i = 0; i < 4; i++)
 190         subnet->net.ipv4.address.x[i] = x[i];
 191       return subnet;
 192     }
 193
 194   if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 195              &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
 196              &l) == 9)
 197     {
 198       subnet->type = SUBNET_IPV6;
 199       subnet->net.ipv6.masklength = l;
 200       for(i = 0; i < 8; i++)
 201         subnet->net.ipv6.address.x[i] = htons(x[i]);
 202       return subnet;
 203     }
 204
 205   if(sscanf(subnetstr, "%hu.%hu.%hu.%hu",
 206               &x[0], &x[1], &x[2], &x[3]) == 4)
 207     {
 208       subnet->type = SUBNET_IPV4;
 209       subnet->net.ipv4.masklength = 32;
 210       for(i = 0; i < 4; i++)
 211         subnet->net.ipv4.address.x[i] = x[i];
 212       return subnet;
 213     }
 214
 215   if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
 216              &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7]) == 8)
 217     {
 218       subnet->type = SUBNET_IPV6;
 219       subnet->net.ipv6.masklength = 128;
 220       for(i = 0; i < 8; i++)
 221         subnet->net.ipv6.address.x[i] = htons(x[i]);
 222       return subnet;
 223     }
 224
 225   if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 226               &x[0], &x[1], &x[2], &x[3], &x[4], &x[5]) == 6)
 227     {
 228       subnet->type = SUBNET_MAC;
 229       for(i = 0; i < 6; i++)
 230         subnet->net.mac.address.x[i] = x[i];
 231       return subnet;
 232     }
 233
 234   free(subnet);
 235   return NULL;
 236 }
 237
 238 char *net2str(subnet_t *subnet)
 239 {
 240   char *netstr;
 241 cp
 242   switch(subnet->type)
 243     {
 244       case SUBNET_MAC:
 245         asprintf(&netstr, "%hx:%hx:%hx:%hx:%hx:%hx",
 246                    subnet->net.mac.address.x[0],
 247                    subnet->net.mac.address.x[1],
 248                    subnet->net.mac.address.x[2],
 249                    subnet->net.mac.address.x[3],
 250                    subnet->net.mac.address.x[4],
 251                    subnet->net.mac.address.x[5]);
 252         break;
 253       case SUBNET_IPV4:
 254         asprintf(&netstr, "%hu.%hu.%hu.%hu/%d",
 255                    subnet->net.ipv4.address.x[0],
 256                    subnet->net.ipv4.address.x[1],
 257                    subnet->net.ipv4.address.x[2],
 258                    subnet->net.ipv4.address.x[3],
 259                    subnet->net.ipv4.masklength);
 260         break;
 261       case SUBNET_IPV6:
 262         asprintf(&netstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d",
 263                    ntohs(subnet->net.ipv6.address.x[0]),
 264                    ntohs(subnet->net.ipv6.address.x[1]),
 265                    ntohs(subnet->net.ipv6.address.x[2]),
 266                    ntohs(subnet->net.ipv6.address.x[3]),
 267                    ntohs(subnet->net.ipv6.address.x[4]),
 268                    ntohs(subnet->net.ipv6.address.x[5]),
 269                    ntohs(subnet->net.ipv6.address.x[6]),
 270                    ntohs(subnet->net.ipv6.address.x[7]),
 271                    subnet->net.ipv6.masklength);
 272         break;
 273       default:
 274         syslog(LOG_ERR, _("net2str() was called with unknown subnet type %d, exitting!"), subnet->type);
 275         cp_trace();
 276         exit(0);
 277     }
 278 cp
 279   return netstr;
 280 }
 281
 282 /* Subnet lookup routines */
 283
 284 subnet_t *lookup_subnet(node_t *owner, subnet_t *subnet)
 285 {
 286 cp
 287   return avl_search(owner->subnet_tree, subnet);
 288 }
 289
 290 subnet_t *lookup_subnet_mac(mac_t *address)
 291 {
 292   subnet_t subnet, *p;
 293 cp
 294   subnet.type = SUBNET_MAC;
 295   memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
 296
 297   p = (subnet_t *)avl_search(subnet_tree, &subnet);
 298 cp
 299   return p;
 300 }
 301
 302 subnet_t *lookup_subnet_ipv4(ipv4_t *address)
 303 {
 304   subnet_t subnet, *p;
 305 cp
 306   subnet.type = SUBNET_IPV4;
 307   memcpy(&subnet.net.ipv4.address, address, sizeof(ipv4_t));
 308   subnet.net.ipv4.masklength = 32;
 309
 310   do
 311   {
 312     /* Go find subnet */
 313
 314     p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
 315
 316   /* Check if the found subnet REALLY matches */
 317 cp
 318     if(p)
 319       {
 320         if(p->type != SUBNET_IPV4)
 321           {
 322             p = NULL;
 323             break;
 324           }
 325
 326         if (!maskcmp((char *)address, (char *)&p->net.ipv4.address, p->net.ipv4.masklength, sizeof(ipv4_t)))
 327           break;
 328         else
 329           {
 330             /* Otherwise, see if there is a bigger enclosing subnet */
 331
 332             subnet.net.ipv4.masklength = p->net.ipv4.masklength - 1;
 333             maskcpy((char *)&subnet.net.ipv4.address, (char *)&p->net.ipv4.address, subnet.net.ipv4.masklength, sizeof(ipv4_t));
 334           }
 335       }
 336   } while (p);
 337 cp
 338   return p;
 339 }
 340
 341 subnet_t *lookup_subnet_ipv6(ipv6_t *address)
 342 {
 343   subnet_t subnet, *p;
 344 cp
 345   subnet.type = SUBNET_IPV6;
 346   memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
 347   subnet.net.ipv6.masklength = 128;
 348
 349   do
 350   {
 351     /* Go find subnet */
 352
 353     p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
 354
 355     /* Check if the found subnet REALLY matches */
 356
 357 cp
 358     if(p)
 359       {
 360         if(p->type != SUBNET_IPV6)
 361           return NULL;
 362
 363         if (!maskcmp((char *)address, (char *)&p->net.ipv6.address, p->net.ipv6.masklength, sizeof(ipv6_t)))
 364           break;
 365         else
 366           {
 367             /* Otherwise, see if there is a bigger enclosing subnet */
 368
 369             subnet.net.ipv6.masklength = p->net.ipv6.masklength - 1;
 370             maskcpy((char *)&subnet.net.ipv6.address, (char *)&p->net.ipv6.address, subnet.net.ipv6.masklength, sizeof(ipv6_t));
 371           }
 372       }
 373    } while (p);
 374 cp
 375   return p;
 376 }
 377
 378 void dump_subnets(void)
 379 {
 380   char *netstr;
 381   subnet_t *subnet;
 382   avl_node_t *node;
 383 cp
 384   syslog(LOG_DEBUG, _("Subnet list:"));
 385   for(node = subnet_tree->head; node; node = node->next)
 386     {
 387       subnet = (subnet_t *)node->data;
 388       netstr = net2str(subnet);
 389       syslog(LOG_DEBUG, _(" %s owner %s"), netstr, subnet->owner->name);
 390       free(netstr);
 391     }
 392   syslog(LOG_DEBUG, _("End of subnet list."));
 393 cp
 394 }