src/subnet.c

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000 Guus Sliepen <guus@sliepen.warande.net>,
   4                   2000 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 1.1.2.16 2001/01/05 23:53:53 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <stdio.h>
  26 #include <syslog.h>
  27
  28 #include "conf.h"
  29 #include "net.h"
  30 #include "connection.h"
  31 #include "subnet.h"
  32 #include "system.h"
  33
  34 #include <utils.h>
  35 #include <xalloc.h>
  36 #include <avl_tree.h>
  37
  38 /* lists type of subnet */
  39
  40 avl_tree_t *subnet_tree;
  41
  42 void init_subnets(void)
  43 {
  44 cp
  45   subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
  46 cp
  47 }
  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 cp
  60   /* If the subnet of a falls within the range of subnet b,
  61      then we consider a smaller then b.
  62      Otherwise, the addresses alone (and not the subnet masks) will be compared.
  63    */
  64
  65   if(a->net.ipv4.mask > b->net.ipv4.mask)
  66     if((a->net.ipv4.address & b->net.ipv4.mask) == b->net.ipv4.address)
  67       return -1;
  68
  69   return a->net.ipv4.address - b->net.ipv4.address;
  70 }
  71
  72 int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
  73 {
  74 cp
  75   /* Same as ipv4 case, but with nasty 128 bit addresses */
  76
  77   if(memcmp(&a->net.ipv6.mask, &b->net.ipv6.mask, sizeof(ipv6_t)) > 0)
  78     if((a->net.ipv6.address.x[0] & b->net.ipv6.mask.x[0]) == b->net.ipv6.address.x[0] &&
  79        (a->net.ipv6.address.x[1] & b->net.ipv6.mask.x[1]) == b->net.ipv6.address.x[1] &&
  80        (a->net.ipv6.address.x[2] & b->net.ipv6.mask.x[2]) == b->net.ipv6.address.x[2] &&
  81        (a->net.ipv6.address.x[3] & b->net.ipv6.mask.x[3]) == b->net.ipv6.address.x[3] &&
  82        (a->net.ipv6.address.x[4] & b->net.ipv6.mask.x[4]) == b->net.ipv6.address.x[4] &&
  83        (a->net.ipv6.address.x[5] & b->net.ipv6.mask.x[5]) == b->net.ipv6.address.x[5] &&
  84        (a->net.ipv6.address.x[6] & b->net.ipv6.mask.x[6]) == b->net.ipv6.address.x[6] &&
  85        (a->net.ipv6.address.x[7] & b->net.ipv6.mask.x[7]) == b->net.ipv6.address.x[7])
  86       return -1;
  87
  88   return memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
  89 }
  90
  91 int subnet_compare(subnet_t *a, subnet_t *b)
  92 {
  93   int x;
  94 cp
  95   x = a->type - b->type;
  96   if(x)
  97     return x;
  98
  99   switch(a->type)
 100     {
 101       case SUBNET_MAC:
 102         return subnet_compare_mac(a, b);
 103       case SUBNET_IPV4:
 104         return subnet_compare_ipv4(a, b);
 105       case SUBNET_IPV6:
 106         return subnet_compare_ipv6(a, b);
 107       default:
 108         syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, restarting!"), a->type);
 109         sighup = 1;
 110         return 0;
 111     }
 112 }
 113
 114 /* Allocating and freeing space for subnets */
 115
 116 subnet_t *new_subnet(void)
 117 {
 118 cp
 119   return (subnet_t *)xmalloc(sizeof(subnet_t));
 120 }
 121
 122 void free_subnet(subnet_t *subnet)
 123 {
 124 cp
 125   free(subnet);
 126 }
 127
 128 /* Linked list management */
 129
 130 void subnet_add(connection_t *cl, subnet_t *subnet)
 131 {
 132 cp
 133   subnet->owner = cl;
 134   avl_insert(subnet_tree, subnet);
 135   avl_insert(cl->subnet_tree, subnet);
 136 cp
 137 }
 138
 139 void subnet_del(subnet_t *subnet)
 140 {
 141 cp
 142   avl_delete(subnet->owner->subnet_tree, subnet);
 143 cp
 144   avl_delete(subnet_tree, subnet);
 145 cp
 146 }
 147
 148 /* Ascii representation of subnets */
 149
 150 subnet_t *str2net(char *subnetstr)
 151 {
 152   int type;
 153   subnet_t *subnet;
 154 cp
 155   if(sscanf(subnetstr, "%d,", &type) != 1)
 156     return NULL;
 157 cp
 158   subnet = new_subnet();
 159 cp
 160   switch(type)
 161     {
 162       case SUBNET_MAC:
 163         if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
 164                    &subnet->net.mac.address.x[0],
 165                    &subnet->net.mac.address.x[1],
 166                    &subnet->net.mac.address.x[2],
 167                    &subnet->net.mac.address.x[3],
 168                    &subnet->net.mac.address.x[4],
 169                    &subnet->net.mac.address.x[5]) != 7)
 170           {
 171             free_subnet(subnet);
 172             return NULL;
 173           }
 174         break;
 175       case SUBNET_IPV4:
 176         if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
 177           {
 178             free_subnet(subnet);
 179             return NULL;
 180           }
 181         break;
 182       case SUBNET_IPV6:
 183         if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
 184                    &subnet->net.ipv6.address.x[0],
 185                    &subnet->net.ipv6.address.x[1],
 186                    &subnet->net.ipv6.address.x[2],
 187                    &subnet->net.ipv6.address.x[3],
 188                    &subnet->net.ipv6.address.x[4],
 189                    &subnet->net.ipv6.address.x[5],
 190                    &subnet->net.ipv6.address.x[6],
 191                    &subnet->net.ipv6.address.x[7],
 192                    &subnet->net.ipv6.mask.x[0],
 193                    &subnet->net.ipv6.mask.x[1],
 194                    &subnet->net.ipv6.mask.x[2],
 195                    &subnet->net.ipv6.mask.x[3],
 196                    &subnet->net.ipv6.mask.x[4],
 197                    &subnet->net.ipv6.mask.x[5],
 198                    &subnet->net.ipv6.mask.x[6],
 199                    &subnet->net.ipv6.mask.x[7]) != 17)
 200           {
 201             free_subnet(subnet);
 202             return NULL;
 203           }
 204         break;
 205       default:
 206         free_subnet(subnet);
 207         return NULL;
 208     }
 209 cp
 210   return subnet;
 211 }
 212
 213 char *net2str(subnet_t *subnet)
 214 {
 215   char *netstr;
 216 cp
 217   switch(subnet->type)
 218     {
 219       case SUBNET_MAC:
 220         asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
 221                    subnet->net.mac.address.x[0],
 222                    subnet->net.mac.address.x[1],
 223                    subnet->net.mac.address.x[2],
 224                    subnet->net.mac.address.x[3],
 225                    subnet->net.mac.address.x[4],
 226                    subnet->net.mac.address.x[5]);
 227         break;
 228       case SUBNET_IPV4:
 229         asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
 230         break;
 231       case SUBNET_IPV6:
 232         asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", subnet->type,
 233                    subnet->net.ipv6.address.x[0],
 234                    subnet->net.ipv6.address.x[1],
 235                    subnet->net.ipv6.address.x[2],
 236                    subnet->net.ipv6.address.x[3],
 237                    subnet->net.ipv6.address.x[4],
 238                    subnet->net.ipv6.address.x[5],
 239                    subnet->net.ipv6.address.x[6],
 240                    subnet->net.ipv6.address.x[7],
 241                    subnet->net.ipv6.mask.x[0],
 242                    subnet->net.ipv6.mask.x[1],
 243                    subnet->net.ipv6.mask.x[2],
 244                    subnet->net.ipv6.mask.x[3],
 245                    subnet->net.ipv6.mask.x[4],
 246                    subnet->net.ipv6.mask.x[5],
 247                    subnet->net.ipv6.mask.x[6],
 248                    subnet->net.ipv6.mask.x[7]);
 249         break;
 250       default:
 251         asprintf(&netstr, _("unknown"));
 252     }
 253 cp
 254   return netstr;
 255 }
 256
 257 /* Subnet lookup routines */
 258
 259 subnet_t *lookup_subnet_mac(mac_t *address)
 260 {
 261   subnet_t subnet, *p;
 262 cp
 263   subnet.type = SUBNET_MAC;
 264   memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
 265
 266   p = (subnet_t *)avl_search(subnet_tree, &subnet);
 267 cp
 268   return p;
 269 }
 270
 271 subnet_t *lookup_subnet_ipv4(ipv4_t *address)
 272 {
 273   subnet_t subnet, *p;
 274 cp
 275   subnet.type = SUBNET_IPV4;
 276   subnet.net.ipv4.address = *address;
 277   subnet.net.ipv4.mask = 0xFFFFFFFF;
 278
 279   p = (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
 280
 281   /* Check if the found subnet REALLY matches */
 282 cp
 283   if(p && ((*address & p->net.ipv4.mask) == p->net.ipv4.address))
 284     return p;
 285   else
 286     return NULL;
 287 }
 288
 289 subnet_t *lookup_subnet_ipv6(ipv6_t *address)
 290 {
 291   subnet_t subnet;
 292 cp
 293   subnet.type = SUBNET_IPV6;
 294   memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
 295   memset(&subnet.net.ipv6.mask, 0xFF, 16);
 296
 297 /* FIXME: check if it REALLY matches */
 298
 299   return (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
 300 }
 301
 302 void dump_subnet_list(void)
 303 {
 304   char *netstr;
 305   subnet_t *subnet;
 306   avl_node_t *node;
 307 cp
 308   syslog(LOG_DEBUG, _("Subnet list:"));
 309   for(node = subnet_tree->head; node; node = node->next)
 310     {
 311       subnet = (subnet_t *)node->data;
 312       netstr = net2str(subnet);
 313       syslog(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
 314       free(netstr);
 315     }
 316   syslog(LOG_DEBUG, _("End of subnet list."));
 317 cp
 318 }