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 1.1.2.27 2001/10/28 22:42:49 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 /* Subnet comparison */
  44
  45 int subnet_compare_mac(subnet_t *a, subnet_t *b)
  46 {
  47   int result;
  48 cp
  49   result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  50
  51   if(result)
  52     return result;
  53
  54   return strcmp(a->owner->name, b->owner->name);
  55 }
  56
  57 int subnet_compare_ipv4(subnet_t *a, subnet_t *b)
  58 {
  59 cp
  60   /* We compare as if a subnet is a number that equals (address << 32 + netmask). */
  61
  62   if(a->net.ipv4.address < b->net.ipv4.address)
  63     return -1;
  64   else if(a->net.ipv4.address > b->net.ipv4.address)
  65     return 1;
  66
  67   if(a->net.ipv4.mask < b->net.ipv4.mask)
  68     return -1;
  69   else if(a->net.ipv4.mask > b->net.ipv4.mask)
  70     return 1;
  71
  72   return strcmp(a->owner->name, b->owner->name);
  73 }
  74
  75 int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
  76 {
  77   int result;
  78 cp
  79   /* Same as ipv4 case, but with nasty 128 bit addresses */
  80
  81   result = memcmp(a->net.ipv6.address.x, b->net.ipv6.address.x, sizeof(ipv6_t));
  82
  83   if(result)
  84     return result;
  85
  86   result = memcmp(a->net.ipv6.mask.x, b->net.ipv6.mask.x, sizeof(ipv6_t));
  87
  88   if(result)
  89     return result;
  90
  91   return strcmp(a->owner->name, b->owner->name);
  92 }
  93
  94 int subnet_compare(subnet_t *a, subnet_t *b)
  95 {
  96   int x;
  97 cp
  98   x = a->type - b->type;
  99   if(x)
 100     return x;
 101
 102   switch(a->type)
 103     {
 104       case SUBNET_MAC:
 105         return subnet_compare_mac(a, b);
 106       case SUBNET_IPV4:
 107         return subnet_compare_ipv4(a, b);
 108       case SUBNET_IPV6:
 109         return subnet_compare_ipv6(a, b);
 110       default:
 111         syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, restarting!"), a->type);
 112         sighup = 1;
 113         return 0;
 114     }
 115 }
 116
 117 /* Initialising trees */
 118
 119 void init_subnets(void)
 120 {
 121 cp
 122   subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
 123 cp
 124 }
 125
 126 void exit_subnets(void)
 127 {
 128 cp
 129   avl_delete_tree(subnet_tree);
 130 cp
 131 }
 132
 133 avl_tree_t *new_subnet_tree(void)
 134 {
 135 cp
 136   return avl_alloc_tree((avl_compare_t)subnet_compare, NULL);
 137 cp
 138 }
 139
 140 void free_subnet_tree(avl_tree_t *subnet_tree)
 141 {
 142 cp
 143   avl_delete_tree(subnet_tree);
 144 cp
 145 }
 146
 147 /* Allocating and freeing space for subnets */
 148
 149 subnet_t *new_subnet(void)
 150 {
 151 cp
 152   return (subnet_t *)xmalloc(sizeof(subnet_t));
 153 }
 154
 155 void free_subnet(subnet_t *subnet)
 156 {
 157 cp
 158   free(subnet);
 159 }
 160
 161 /* Linked list management */
 162
 163 void subnet_add(node_t *n, subnet_t *subnet)
 164 {
 165 cp
 166   subnet->owner = n;
 167
 168   avl_insert(subnet_tree, subnet);
 169 cp
 170   avl_insert(n->subnet_tree, subnet);
 171 cp
 172 }
 173
 174 void subnet_del(node_t *n, subnet_t *subnet)
 175 {
 176 cp
 177   avl_delete(n->subnet_tree, subnet);
 178 cp
 179   avl_delete(subnet_tree, subnet);
 180 cp
 181 }
 182
 183 /* Ascii representation of subnets */
 184
 185 subnet_t *str2net(char *subnetstr)
 186 {
 187   int type;
 188   subnet_t *subnet;
 189 cp
 190   if(sscanf(subnetstr, "%d,", &type) != 1)
 191     return NULL;
 192 cp
 193   subnet = new_subnet();
 194 cp
 195   switch(type)
 196     {
 197       case SUBNET_MAC:
 198         if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
 199                    &subnet->net.mac.address.x[0],
 200                    &subnet->net.mac.address.x[1],
 201                    &subnet->net.mac.address.x[2],
 202                    &subnet->net.mac.address.x[3],
 203                    &subnet->net.mac.address.x[4],
 204                    &subnet->net.mac.address.x[5]) != 7)
 205           {
 206             free_subnet(subnet);
 207             return NULL;
 208           }
 209         break;
 210       case SUBNET_IPV4:
 211         if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
 212           {
 213             free_subnet(subnet);
 214             return NULL;
 215           }
 216         break;
 217       case SUBNET_IPV6:
 218         if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
 219                    &subnet->net.ipv6.address.x[0],
 220                    &subnet->net.ipv6.address.x[1],
 221                    &subnet->net.ipv6.address.x[2],
 222                    &subnet->net.ipv6.address.x[3],
 223                    &subnet->net.ipv6.address.x[4],
 224                    &subnet->net.ipv6.address.x[5],
 225                    &subnet->net.ipv6.address.x[6],
 226                    &subnet->net.ipv6.address.x[7],
 227                    &subnet->net.ipv6.mask.x[0],
 228                    &subnet->net.ipv6.mask.x[1],
 229                    &subnet->net.ipv6.mask.x[2],
 230                    &subnet->net.ipv6.mask.x[3],
 231                    &subnet->net.ipv6.mask.x[4],
 232                    &subnet->net.ipv6.mask.x[5],
 233                    &subnet->net.ipv6.mask.x[6],
 234                    &subnet->net.ipv6.mask.x[7]) != 17)
 235           {
 236             free_subnet(subnet);
 237             return NULL;
 238           }
 239         break;
 240       default:
 241         free_subnet(subnet);
 242         return NULL;
 243     }
 244 cp
 245   return subnet;
 246 }
 247
 248 char *net2str(subnet_t *subnet)
 249 {
 250   char *netstr;
 251 cp
 252   switch(subnet->type)
 253     {
 254       case SUBNET_MAC:
 255         asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
 256                    subnet->net.mac.address.x[0],
 257                    subnet->net.mac.address.x[1],
 258                    subnet->net.mac.address.x[2],
 259                    subnet->net.mac.address.x[3],
 260                    subnet->net.mac.address.x[4],
 261                    subnet->net.mac.address.x[5]);
 262         break;
 263       case SUBNET_IPV4:
 264         asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
 265         break;
 266       case SUBNET_IPV6:
 267         asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", subnet->type,
 268                    subnet->net.ipv6.address.x[0],
 269                    subnet->net.ipv6.address.x[1],
 270                    subnet->net.ipv6.address.x[2],
 271                    subnet->net.ipv6.address.x[3],
 272                    subnet->net.ipv6.address.x[4],
 273                    subnet->net.ipv6.address.x[5],
 274                    subnet->net.ipv6.address.x[6],
 275                    subnet->net.ipv6.address.x[7],
 276                    subnet->net.ipv6.mask.x[0],
 277                    subnet->net.ipv6.mask.x[1],
 278                    subnet->net.ipv6.mask.x[2],
 279                    subnet->net.ipv6.mask.x[3],
 280                    subnet->net.ipv6.mask.x[4],
 281                    subnet->net.ipv6.mask.x[5],
 282                    subnet->net.ipv6.mask.x[6],
 283                    subnet->net.ipv6.mask.x[7]);
 284         break;
 285       default:
 286         asprintf(&netstr, _("unknown subnet type"));
 287     }
 288 cp
 289   return netstr;
 290 }
 291
 292 /* Subnet lookup routines */
 293
 294 subnet_t *lookup_subnet(node_t *owner, subnet_t *subnet)
 295 {
 296 cp
 297   return avl_search(owner->subnet_tree, subnet);
 298 }
 299
 300 subnet_t *lookup_subnet_mac(mac_t *address)
 301 {
 302   subnet_t subnet, *p;
 303 cp
 304   subnet.type = SUBNET_MAC;
 305   memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
 306
 307   p = (subnet_t *)avl_search(subnet_tree, &subnet);
 308 cp
 309   return p;
 310 }
 311
 312 subnet_t *lookup_subnet_ipv4(ipv4_t *address)
 313 {
 314   subnet_t subnet, *p;
 315 cp
 316   subnet.type = SUBNET_IPV4;
 317   subnet.net.ipv4.address = *address;
 318   subnet.net.ipv4.mask = 0xFFFFFFFF;
 319
 320   do
 321   {
 322     /* Go find subnet */
 323
 324     p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
 325
 326   /* Check if the found subnet REALLY matches */
 327 cp
 328     if(p)
 329       {
 330         if ((*address & p->net.ipv4.mask) == p->net.ipv4.address)
 331           break;
 332         else
 333           {
 334             /* Otherwise, see if there is a bigger enclosing subnet */
 335
 336             subnet.net.ipv4.mask = p->net.ipv4.mask << 1;
 337             subnet.net.ipv4.address = p->net.ipv4.address & subnet.net.ipv4.mask;
 338           }
 339       }
 340    } while (p);
 341
 342    return p;
 343 }
 344
 345 subnet_t *lookup_subnet_ipv6(ipv6_t *address)
 346 {
 347   subnet_t subnet, *p;
 348   int i;
 349 cp
 350   subnet.type = SUBNET_IPV6;
 351   memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
 352   memset(&subnet.net.ipv6.mask, 0xFF, 16);
 353
 354   p = (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
 355
 356   if(p)
 357     for(i=0; i<8; i++)
 358       if((address->x[i] & p->net.ipv6.address.x[i]) != p->net.ipv6.address.x[i])
 359         return NULL;
 360
 361   return p;
 362 }
 363
 364 void dump_subnets(void)
 365 {
 366   char *netstr;
 367   subnet_t *subnet;
 368   avl_node_t *node;
 369 cp
 370   syslog(LOG_DEBUG, _("Subnet list:"));
 371   for(node = subnet_tree->head; node; node = node->next)
 372     {
 373       subnet = (subnet_t *)node->data;
 374       netstr = net2str(subnet);
 375       syslog(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
 376       free(netstr);
 377     }
 378   syslog(LOG_DEBUG, _("End of subnet list."));
 379 cp
 380 }