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

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000,2001 Guus Sliepen <guus@sliepen.warande.net>,
   4                   2000,2001 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 1.1.2.26 2001/10/27 13:13:35 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <stdio.h>
  26 #include <syslog.h>
  27 #include <string.h>
  28
  29 #include "conf.h"
  30 #include "net.h"
  31 #include "node.h"
  32 #include "subnet.h"
  33 #include "system.h"
  34
  35 #include <utils.h>
  36 #include <xalloc.h>
  37 #include <avl_tree.h>
  38
  39 /* lists type of subnet */
  40
  41 avl_tree_t *subnet_tree;
  42
  43 void init_subnets(void)
  44 {
  45 cp
  46   subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
  47 cp
  48 }
  49
  50 /* Subnet comparison */
  51
  52 int subnet_compare_mac(subnet_t *a, subnet_t *b)
  53 {
  54   int result;
  55 cp
  56   result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  57
  58   if(result)
  59     return result;
  60
  61   return strcmp(a->owner->name, b->owner->name);
  62 }
  63
  64 int subnet_compare_ipv4(subnet_t *a, subnet_t *b)
  65 {
  66 cp
  67   /* We compare as if a subnet is a number that equals (address << 32 + netmask). */
  68
  69   if(a->net.ipv4.address < b->net.ipv4.address)
  70     return -1;
  71   else if(a->net.ipv4.address > b->net.ipv4.address)
  72     return 1;
  73
  74   if(a->net.ipv4.mask < b->net.ipv4.mask)
  75     return -1;
  76   else if(a->net.ipv4.mask > b->net.ipv4.mask)
  77     return 1;
  78
  79   return strcmp(a->owner->name, b->owner->name);
  80 }
  81
  82 int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
  83 {
  84   int result;
  85 cp
  86   /* Same as ipv4 case, but with nasty 128 bit addresses */
  87
  88   result = memcmp(a->net.ipv6.address.x, b->net.ipv6.address.x, sizeof(ipv6_t));
  89
  90   if(result)
  91     return result;
  92
  93   result = memcmp(a->net.ipv6.mask.x, b->net.ipv6.mask.x, sizeof(ipv6_t));
  94
  95   if(result)
  96     return result;
  97
  98   return strcmp(a->owner->name, b->owner->name);
  99 }
 100
 101 int subnet_compare(subnet_t *a, subnet_t *b)
 102 {
 103   int x;
 104 cp
 105   x = a->type - b->type;
 106   if(x)
 107     return x;
 108
 109   switch(a->type)
 110     {
 111       case SUBNET_MAC:
 112         return subnet_compare_mac(a, b);
 113       case SUBNET_IPV4:
 114         return subnet_compare_ipv4(a, b);
 115       case SUBNET_IPV6:
 116         return subnet_compare_ipv6(a, b);
 117       default:
 118         syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, restarting!"), a->type);
 119         sighup = 1;
 120         return 0;
 121     }
 122 }
 123
 124 /* Allocating and freeing space for subnets */
 125
 126 subnet_t *new_subnet(void)
 127 {
 128 cp
 129   return (subnet_t *)xmalloc(sizeof(subnet_t));
 130 }
 131
 132 void free_subnet(subnet_t *subnet)
 133 {
 134 cp
 135   free(subnet);
 136 }
 137
 138 /* Linked list management */
 139
 140 void subnet_add(node_t *n, subnet_t *subnet)
 141 {
 142 cp
 143   subnet->owner = n;
 144
 145   avl_insert(subnet_tree, subnet);
 146 cp
 147   avl_insert(n->subnet_tree, subnet);
 148 cp
 149 }
 150
 151 void subnet_del(node_t *n, subnet_t *subnet)
 152 {
 153 cp
 154   avl_delete(n->subnet_tree, subnet);
 155 cp
 156   avl_delete(subnet_tree, subnet);
 157 cp
 158 }
 159
 160 /* Ascii representation of subnets */
 161
 162 subnet_t *str2net(char *subnetstr)
 163 {
 164   int type;
 165   subnet_t *subnet;
 166 cp
 167   if(sscanf(subnetstr, "%d,", &type) != 1)
 168     return NULL;
 169 cp
 170   subnet = new_subnet();
 171 cp
 172   switch(type)
 173     {
 174       case SUBNET_MAC:
 175         if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
 176                    &subnet->net.mac.address.x[0],
 177                    &subnet->net.mac.address.x[1],
 178                    &subnet->net.mac.address.x[2],
 179                    &subnet->net.mac.address.x[3],
 180                    &subnet->net.mac.address.x[4],
 181                    &subnet->net.mac.address.x[5]) != 7)
 182           {
 183             free_subnet(subnet);
 184             return NULL;
 185           }
 186         break;
 187       case SUBNET_IPV4:
 188         if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
 189           {
 190             free_subnet(subnet);
 191             return NULL;
 192           }
 193         break;
 194       case SUBNET_IPV6:
 195         if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
 196                    &subnet->net.ipv6.address.x[0],
 197                    &subnet->net.ipv6.address.x[1],
 198                    &subnet->net.ipv6.address.x[2],
 199                    &subnet->net.ipv6.address.x[3],
 200                    &subnet->net.ipv6.address.x[4],
 201                    &subnet->net.ipv6.address.x[5],
 202                    &subnet->net.ipv6.address.x[6],
 203                    &subnet->net.ipv6.address.x[7],
 204                    &subnet->net.ipv6.mask.x[0],
 205                    &subnet->net.ipv6.mask.x[1],
 206                    &subnet->net.ipv6.mask.x[2],
 207                    &subnet->net.ipv6.mask.x[3],
 208                    &subnet->net.ipv6.mask.x[4],
 209                    &subnet->net.ipv6.mask.x[5],
 210                    &subnet->net.ipv6.mask.x[6],
 211                    &subnet->net.ipv6.mask.x[7]) != 17)
 212           {
 213             free_subnet(subnet);
 214             return NULL;
 215           }
 216         break;
 217       default:
 218         free_subnet(subnet);
 219         return NULL;
 220     }
 221 cp
 222   return subnet;
 223 }
 224
 225 char *net2str(subnet_t *subnet)
 226 {
 227   char *netstr;
 228 cp
 229   switch(subnet->type)
 230     {
 231       case SUBNET_MAC:
 232         asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
 233                    subnet->net.mac.address.x[0],
 234                    subnet->net.mac.address.x[1],
 235                    subnet->net.mac.address.x[2],
 236                    subnet->net.mac.address.x[3],
 237                    subnet->net.mac.address.x[4],
 238                    subnet->net.mac.address.x[5]);
 239         break;
 240       case SUBNET_IPV4:
 241         asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
 242         break;
 243       case SUBNET_IPV6:
 244         asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", subnet->type,
 245                    subnet->net.ipv6.address.x[0],
 246                    subnet->net.ipv6.address.x[1],
 247                    subnet->net.ipv6.address.x[2],
 248                    subnet->net.ipv6.address.x[3],
 249                    subnet->net.ipv6.address.x[4],
 250                    subnet->net.ipv6.address.x[5],
 251                    subnet->net.ipv6.address.x[6],
 252                    subnet->net.ipv6.address.x[7],
 253                    subnet->net.ipv6.mask.x[0],
 254                    subnet->net.ipv6.mask.x[1],
 255                    subnet->net.ipv6.mask.x[2],
 256                    subnet->net.ipv6.mask.x[3],
 257                    subnet->net.ipv6.mask.x[4],
 258                    subnet->net.ipv6.mask.x[5],
 259                    subnet->net.ipv6.mask.x[6],
 260                    subnet->net.ipv6.mask.x[7]);
 261         break;
 262       default:
 263         asprintf(&netstr, _("unknown subnet type"));
 264     }
 265 cp
 266   return netstr;
 267 }
 268
 269 /* Subnet lookup routines */
 270
 271 subnet_t *lookup_subnet(node_t *owner, subnet_t *subnet)
 272 {
 273 cp
 274   return avl_search(owner->subnet_tree, subnet);
 275 }
 276
 277 subnet_t *lookup_subnet_mac(mac_t *address)
 278 {
 279   subnet_t subnet, *p;
 280 cp
 281   subnet.type = SUBNET_MAC;
 282   memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
 283
 284   p = (subnet_t *)avl_search(subnet_tree, &subnet);
 285 cp
 286   return p;
 287 }
 288
 289 subnet_t *lookup_subnet_ipv4(ipv4_t *address)
 290 {
 291   subnet_t subnet, *p;
 292 cp
 293   subnet.type = SUBNET_IPV4;
 294   subnet.net.ipv4.address = *address;
 295   subnet.net.ipv4.mask = 0xFFFFFFFF;
 296
 297   do
 298   {
 299     /* Go find subnet */
 300
 301     p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
 302
 303   /* Check if the found subnet REALLY matches */
 304 cp
 305     if(p)
 306       {
 307         if ((*address & p->net.ipv4.mask) == p->net.ipv4.address)
 308           break;
 309         else
 310           {
 311             /* Otherwise, see if there is a bigger enclosing subnet */
 312
 313             subnet.net.ipv4.mask = p->net.ipv4.mask << 1;
 314             subnet.net.ipv4.address = p->net.ipv4.address & subnet.net.ipv4.mask;
 315           }
 316       }
 317    } while (p);
 318
 319    return p;
 320 }
 321
 322 subnet_t *lookup_subnet_ipv6(ipv6_t *address)
 323 {
 324   subnet_t subnet, *p;
 325   int i;
 326 cp
 327   subnet.type = SUBNET_IPV6;
 328   memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
 329   memset(&subnet.net.ipv6.mask, 0xFF, 16);
 330
 331   p = (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
 332
 333   if(p)
 334     for(i=0; i<8; i++)
 335       if((address->x[i] & p->net.ipv6.address.x[i]) != p->net.ipv6.address.x[i])
 336         return NULL;
 337
 338   return p;
 339 }
 340
 341 void dump_subnets(void)
 342 {
 343   char *netstr;
 344   subnet_t *subnet;
 345   avl_node_t *node;
 346 cp
 347   syslog(LOG_DEBUG, _("Subnet list:"));
 348   for(node = subnet_tree->head; node; node = node->next)
 349     {
 350       subnet = (subnet_t *)node->data;
 351       netstr = net2str(subnet);
 352       syslog(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
 353       free(netstr);
 354     }
 355   syslog(LOG_DEBUG, _("End of subnet list."));
 356 cp
 357 }