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 1.1.2.28 2001/10/30 12:59:12 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 cp
  48   return memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
  49 }
  50
  51 int subnet_compare_ipv4(subnet_t *a, subnet_t *b)
  52 {
  53 cp
  54   /* We compare as if a subnet is a number that equals (address << 32 + netmask). */
  55
  56   if(a->net.ipv4.address < b->net.ipv4.address)
  57     return -1;
  58   else if(a->net.ipv4.address > b->net.ipv4.address)
  59     return 1;
  60
  61   if(a->net.ipv4.mask < b->net.ipv4.mask)
  62     return -1;
  63   else if(a->net.ipv4.mask > b->net.ipv4.mask)
  64     return 1;
  65
  66   return 0;
  67 }
  68
  69 int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
  70 {
  71   int result;
  72 cp
  73   /* Same as ipv4 case, but with nasty 128 bit addresses */
  74
  75   result = memcmp(a->net.ipv6.address.x, b->net.ipv6.address.x, sizeof(ipv6_t));
  76
  77   if(result)
  78     return result;
  79
  80   result = memcmp(a->net.ipv6.mask.x, b->net.ipv6.mask.x, sizeof(ipv6_t));
  81
  82   if(result)
  83     return result;
  84
  85   return 0;
  86 }
  87
  88 int subnet_compare(subnet_t *a, subnet_t *b)
  89 {
  90   int x;
  91 cp
  92   x = a->type - b->type;
  93   if(x)
  94     return x;
  95
  96   switch(a->type)
  97     {
  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         syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, restarting!"), a->type);
 106         sighup = 1;
 107         return 0;
 108     }
 109 }
 110
 111 /* Initialising trees */
 112
 113 void init_subnets(void)
 114 {
 115 cp
 116   subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
 117 cp
 118 }
 119
 120 void exit_subnets(void)
 121 {
 122 cp
 123   avl_delete_tree(subnet_tree);
 124 cp
 125 }
 126
 127 avl_tree_t *new_subnet_tree(void)
 128 {
 129 cp
 130   return avl_alloc_tree((avl_compare_t)subnet_compare, NULL);
 131 cp
 132 }
 133
 134 void free_subnet_tree(avl_tree_t *subnet_tree)
 135 {
 136 cp
 137   avl_delete_tree(subnet_tree);
 138 cp
 139 }
 140
 141 /* Allocating and freeing space for subnets */
 142
 143 subnet_t *new_subnet(void)
 144 {
 145 cp
 146   return (subnet_t *)xmalloc(sizeof(subnet_t));
 147 }
 148
 149 void free_subnet(subnet_t *subnet)
 150 {
 151 cp
 152   free(subnet);
 153 }
 154
 155 /* Adding and removing subnets */
 156
 157 void subnet_add(node_t *n, subnet_t *subnet)
 158 {
 159 cp
 160   subnet->owner = n;
 161
 162   avl_insert(subnet_tree, subnet);
 163 cp
 164   avl_insert(n->subnet_tree, subnet);
 165 cp
 166 }
 167
 168 void subnet_del(node_t *n, subnet_t *subnet)
 169 {
 170 cp
 171   avl_delete(n->subnet_tree, subnet);
 172 cp
 173   avl_delete(subnet_tree, subnet);
 174 cp
 175 }
 176
 177 /* Ascii representation of subnets */
 178
 179 subnet_t *str2net(char *subnetstr)
 180 {
 181   int type;
 182   subnet_t *subnet;
 183 cp
 184   if(sscanf(subnetstr, "%d,", &type) != 1)
 185     return NULL;
 186 cp
 187   subnet = new_subnet();
 188 cp
 189   switch(type)
 190     {
 191       case SUBNET_MAC:
 192         if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
 193                    &subnet->net.mac.address.x[0],
 194                    &subnet->net.mac.address.x[1],
 195                    &subnet->net.mac.address.x[2],
 196                    &subnet->net.mac.address.x[3],
 197                    &subnet->net.mac.address.x[4],
 198                    &subnet->net.mac.address.x[5]) != 7)
 199           {
 200             free_subnet(subnet);
 201             return NULL;
 202           }
 203         break;
 204       case SUBNET_IPV4:
 205         if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
 206           {
 207             free_subnet(subnet);
 208             return NULL;
 209           }
 210         break;
 211       case SUBNET_IPV6:
 212         if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
 213                    &subnet->net.ipv6.address.x[0],
 214                    &subnet->net.ipv6.address.x[1],
 215                    &subnet->net.ipv6.address.x[2],
 216                    &subnet->net.ipv6.address.x[3],
 217                    &subnet->net.ipv6.address.x[4],
 218                    &subnet->net.ipv6.address.x[5],
 219                    &subnet->net.ipv6.address.x[6],
 220                    &subnet->net.ipv6.address.x[7],
 221                    &subnet->net.ipv6.mask.x[0],
 222                    &subnet->net.ipv6.mask.x[1],
 223                    &subnet->net.ipv6.mask.x[2],
 224                    &subnet->net.ipv6.mask.x[3],
 225                    &subnet->net.ipv6.mask.x[4],
 226                    &subnet->net.ipv6.mask.x[5],
 227                    &subnet->net.ipv6.mask.x[6],
 228                    &subnet->net.ipv6.mask.x[7]) != 17)
 229           {
 230             free_subnet(subnet);
 231             return NULL;
 232           }
 233         break;
 234       default:
 235         free_subnet(subnet);
 236         return NULL;
 237     }
 238 cp
 239   return subnet;
 240 }
 241
 242 char *net2str(subnet_t *subnet)
 243 {
 244   char *netstr;
 245 cp
 246   switch(subnet->type)
 247     {
 248       case SUBNET_MAC:
 249         asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
 250                    subnet->net.mac.address.x[0],
 251                    subnet->net.mac.address.x[1],
 252                    subnet->net.mac.address.x[2],
 253                    subnet->net.mac.address.x[3],
 254                    subnet->net.mac.address.x[4],
 255                    subnet->net.mac.address.x[5]);
 256         break;
 257       case SUBNET_IPV4:
 258         asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
 259         break;
 260       case SUBNET_IPV6:
 261         asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", subnet->type,
 262                    subnet->net.ipv6.address.x[0],
 263                    subnet->net.ipv6.address.x[1],
 264                    subnet->net.ipv6.address.x[2],
 265                    subnet->net.ipv6.address.x[3],
 266                    subnet->net.ipv6.address.x[4],
 267                    subnet->net.ipv6.address.x[5],
 268                    subnet->net.ipv6.address.x[6],
 269                    subnet->net.ipv6.address.x[7],
 270                    subnet->net.ipv6.mask.x[0],
 271                    subnet->net.ipv6.mask.x[1],
 272                    subnet->net.ipv6.mask.x[2],
 273                    subnet->net.ipv6.mask.x[3],
 274                    subnet->net.ipv6.mask.x[4],
 275                    subnet->net.ipv6.mask.x[5],
 276                    subnet->net.ipv6.mask.x[6],
 277                    subnet->net.ipv6.mask.x[7]);
 278         break;
 279       default:
 280         asprintf(&netstr, _("unknown subnet type"));
 281     }
 282 cp
 283   return netstr;
 284 }
 285
 286 /* Subnet lookup routines */
 287
 288 subnet_t *lookup_subnet(node_t *owner, subnet_t *subnet)
 289 {
 290 cp
 291   return avl_search(owner->subnet_tree, subnet);
 292 }
 293
 294 subnet_t *lookup_subnet_mac(mac_t *address)
 295 {
 296   subnet_t subnet, *p;
 297 cp
 298   subnet.type = SUBNET_MAC;
 299   memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
 300
 301   p = (subnet_t *)avl_search(subnet_tree, &subnet);
 302 cp
 303   return p;
 304 }
 305
 306 subnet_t *lookup_subnet_ipv4(ipv4_t *address)
 307 {
 308   subnet_t subnet, *p;
 309 cp
 310   subnet.type = SUBNET_IPV4;
 311   subnet.net.ipv4.address = *address;
 312   subnet.net.ipv4.mask = 0xFFFFFFFF;
 313
 314   do
 315   {
 316     /* Go find subnet */
 317
 318     p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
 319
 320   /* Check if the found subnet REALLY matches */
 321 cp
 322     if(p)
 323       {
 324         if ((*address & p->net.ipv4.mask) == p->net.ipv4.address)
 325           break;
 326         else
 327           {
 328             /* Otherwise, see if there is a bigger enclosing subnet */
 329
 330             subnet.net.ipv4.mask = p->net.ipv4.mask << 1;
 331             subnet.net.ipv4.address = p->net.ipv4.address & subnet.net.ipv4.mask;
 332           }
 333       }
 334    } while (p);
 335
 336    return p;
 337 }
 338
 339 subnet_t *lookup_subnet_ipv6(ipv6_t *address)
 340 {
 341   subnet_t subnet, *p;
 342   int i;
 343 cp
 344   subnet.type = SUBNET_IPV6;
 345   memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
 346   memset(&subnet.net.ipv6.mask, 0xFF, 16);
 347
 348   p = (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
 349
 350   if(p)
 351     for(i=0; i<8; i++)
 352       if((address->x[i] & p->net.ipv6.address.x[i]) != p->net.ipv6.address.x[i])
 353         return NULL;
 354
 355   return p;
 356 }
 357
 358 void dump_subnets(void)
 359 {
 360   char *netstr;
 361   subnet_t *subnet;
 362   avl_node_t *node;
 363 cp
 364   syslog(LOG_DEBUG, _("Subnet list:"));
 365   for(node = subnet_tree->head; node; node = node->next)
 366     {
 367       subnet = (subnet_t *)node->data;
 368       netstr = net2str(subnet);
 369       syslog(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
 370       free(netstr);
 371     }
 372   syslog(LOG_DEBUG, _("End of subnet list."));
 373 cp
 374 }