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

   1 /*
   2     subnet.c -- handle subnet lookups and lists
   3     Copyright (C) 2000-2012 Guus Sliepen <guus@tinc-vpn.org>,
   4                   2000-2005 Ivo Timmermans
   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 along
  17     with this program; if not, write to the Free Software Foundation, Inc.,
  18     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21 #include "system.h"
  22
  23 #include "splay_tree.h"
  24 #include "control_common.h"
  25 #include "device.h"
  26 #include "logger.h"
  27 #include "net.h"
  28 #include "netutl.h"
  29 #include "node.h"
  30 #include "process.h"
  31 #include "subnet.h"
  32 #include "utils.h"
  33 #include "xalloc.h"
  34
  35 /* lists type of subnet */
  36
  37 splay_tree_t *subnet_tree;
  38
  39 /* Subnet lookup cache */
  40
  41 static ipv4_t cache_ipv4_address[2];
  42 static subnet_t *cache_ipv4_subnet[2];
  43 static bool cache_ipv4_valid[2];
  44 static int cache_ipv4_slot;
  45
  46 static ipv6_t cache_ipv6_address[2];
  47 static subnet_t *cache_ipv6_subnet[2];
  48 static bool cache_ipv6_valid[2];
  49 static int cache_ipv6_slot;
  50
  51 static mac_t cache_mac_address[2];
  52 static subnet_t *cache_mac_subnet[2];
  53 static bool cache_mac_valid[2];
  54 static int cache_mac_slot;
  55
  56 void subnet_cache_flush(void) {
  57         cache_ipv4_valid[0] = cache_ipv4_valid[1] = false;
  58         cache_ipv6_valid[0] = cache_ipv6_valid[1] = false;
  59         cache_mac_valid[0] = cache_mac_valid[1] = false;
  60 }
  61
  62 /* Initialising trees */
  63
  64 void init_subnets(void) {
  65         subnet_tree = splay_alloc_tree((splay_compare_t) subnet_compare, (splay_action_t) free_subnet);
  66
  67         subnet_cache_flush();
  68 }
  69
  70 void exit_subnets(void) {
  71         splay_delete_tree(subnet_tree);
  72 }
  73
  74 splay_tree_t *new_subnet_tree(void) {
  75         return splay_alloc_tree((splay_compare_t) subnet_compare, NULL);
  76 }
  77
  78 void free_subnet_tree(splay_tree_t *subnet_tree) {
  79         splay_delete_tree(subnet_tree);
  80 }
  81
  82 /* Allocating and freeing space for subnets */
  83
  84 subnet_t *new_subnet(void) {
  85         return xmalloc_and_zero(sizeof(subnet_t));
  86 }
  87
  88 void free_subnet(subnet_t *subnet) {
  89         free(subnet);
  90 }
  91
  92 /* Adding and removing subnets */
  93
  94 void subnet_add(node_t *n, subnet_t *subnet) {
  95         subnet->owner = n;
  96
  97         splay_insert(subnet_tree, subnet);
  98         splay_insert(n->subnet_tree, subnet);
  99
 100         subnet_cache_flush();
 101 }
 102
 103 void subnet_del(node_t *n, subnet_t *subnet) {
 104         splay_delete(n->subnet_tree, subnet);
 105         splay_delete(subnet_tree, subnet);
 106
 107         subnet_cache_flush();
 108 }
 109
 110 /* Subnet lookup routines */
 111
 112 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) {
 113         return splay_search(owner->subnet_tree, subnet);
 114 }
 115
 116 subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
 117         subnet_t *p, *r = NULL;
 118         splay_node_t *n;
 119         int i;
 120
 121         // Check if this address is cached
 122
 123         for(i = 0; i < 2; i++) {
 124                 if(!cache_mac_valid[i])
 125                         continue;
 126                 if(owner && cache_mac_subnet[i] && cache_mac_subnet[i]->owner != owner)
 127                         continue;
 128                 if(!memcmp(address, &cache_mac_address[i], sizeof *address))
 129                         return cache_mac_subnet[i];
 130         }
 131
 132         // Search all subnets for a matching one
 133
 134         for(n = owner ? owner->subnet_tree->head : subnet_tree->head; n; n = n->next) {
 135                 p = n->data;
 136
 137                 if(!p || p->type != SUBNET_MAC)
 138                         continue;
 139
 140                 if(!memcmp(address, &p->net.mac.address, sizeof *address)) {
 141                         r = p;
 142                         if(p->owner->status.reachable)
 143                                 break;
 144                 }
 145         }
 146
 147         // Cache the result
 148
 149         cache_mac_slot = !cache_mac_slot;
 150         memcpy(&cache_mac_address[cache_mac_slot], address, sizeof *address);
 151         cache_mac_subnet[cache_mac_slot] = r;
 152         cache_mac_valid[cache_mac_slot] = true;
 153
 154         return r;
 155 }
 156
 157 subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
 158         subnet_t *p, *r = NULL;
 159         splay_node_t *n;
 160         int i;
 161
 162         // Check if this address is cached
 163
 164         for(i = 0; i < 2; i++) {
 165                 if(!cache_ipv4_valid[i])
 166                         continue;
 167                 if(!memcmp(address, &cache_ipv4_address[i], sizeof *address))
 168                         return cache_ipv4_subnet[i];
 169         }
 170
 171         // Search all subnets for a matching one
 172
 173         for(n = subnet_tree->head; n; n = n->next) {
 174                 p = n->data;
 175
 176                 if(!p || p->type != SUBNET_IPV4)
 177                         continue;
 178
 179                 if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength)) {
 180                         r = p;
 181                         if(p->owner->status.reachable)
 182                                 break;
 183                 }
 184         }
 185
 186         // Cache the result
 187
 188         cache_ipv4_slot = !cache_ipv4_slot;
 189         memcpy(&cache_ipv4_address[cache_ipv4_slot], address, sizeof *address);
 190         cache_ipv4_subnet[cache_ipv4_slot] = r;
 191         cache_ipv4_valid[cache_ipv4_slot] = true;
 192
 193         return r;
 194 }
 195
 196 subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
 197         subnet_t *p, *r = NULL;
 198         splay_node_t *n;
 199         int i;
 200
 201         // Check if this address is cached
 202
 203         for(i = 0; i < 2; i++) {
 204                 if(!cache_ipv6_valid[i])
 205                         continue;
 206                 if(!memcmp(address, &cache_ipv6_address[i], sizeof *address))
 207                         return cache_ipv6_subnet[i];
 208         }
 209
 210         // Search all subnets for a matching one
 211
 212         for(n = subnet_tree->head; n; n = n->next) {
 213                 p = n->data;
 214
 215                 if(!p || p->type != SUBNET_IPV6)
 216                         continue;
 217
 218                 if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength)) {
 219                         r = p;
 220                         if(p->owner->status.reachable)
 221                                 break;
 222                 }
 223         }
 224
 225         // Cache the result
 226
 227         cache_ipv6_slot = !cache_ipv6_slot;
 228         memcpy(&cache_ipv6_address[cache_ipv6_slot], address, sizeof *address);
 229         cache_ipv6_subnet[cache_ipv6_slot] = r;
 230         cache_ipv6_valid[cache_ipv6_slot] = true;
 231
 232         return r;
 233 }
 234
 235 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 236         splay_node_t *node;
 237         int i;
 238         char *envp[9] = {NULL};
 239         char netstr[MAXNETSTR];
 240         char *name, *address, *port;
 241         char empty[] = "";
 242
 243         // Prepare environment variables to be passed to the script
 244
 245         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 246         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 247         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 248         xasprintf(&envp[3], "NODE=%s", owner->name);
 249
 250         if(owner != myself) {
 251                 sockaddr2str(&owner->address, &address, &port);
 252                 // 4 and 5 are reserved for SUBNET and WEIGHT
 253                 xasprintf(&envp[6], "REMOTEADDRESS=%s", address);
 254                 xasprintf(&envp[7], "REMOTEPORT=%s", port);
 255                 free(port);
 256                 free(address);
 257         }
 258
 259         name = up ? "subnet-up" : "subnet-down";
 260
 261         if(!subnet) {
 262                 for(node = owner->subnet_tree->head; node; node = node->next) {
 263                         subnet = node->data;
 264                         if(!net2str(netstr, sizeof netstr, subnet))
 265                                 continue;
 266                         // Strip the weight from the subnet, and put it in its own environment variable
 267                         char *weight = strchr(netstr, '#');
 268                         if(weight)
 269                                 *weight++ = 0;
 270                         else
 271                                 weight = empty;
 272
 273                         // Prepare the SUBNET and WEIGHT variables
 274                         if(envp[4])
 275                                 free(envp[4]);
 276                         if(envp[5])
 277                                 free(envp[5]);
 278                         xasprintf(&envp[4], "SUBNET=%s", netstr);
 279                         xasprintf(&envp[5], "WEIGHT=%s", weight);
 280
 281                         execute_script(name, envp);
 282                 }
 283         } else {
 284                 if(net2str(netstr, sizeof netstr, subnet)) {
 285                         // Strip the weight from the subnet, and put it in its own environment variable
 286                         char *weight = strchr(netstr, '#');
 287                         if(weight)
 288                                 *weight++ = 0;
 289                         else
 290                                 weight = empty;
 291
 292                         // Prepare the SUBNET and WEIGHT variables
 293                         xasprintf(&envp[4], "SUBNET=%s", netstr);
 294                         xasprintf(&envp[5], "WEIGHT=%s", weight);
 295
 296                         execute_script(name, envp);
 297                 }
 298         }
 299
 300         for(i = 0; envp[i] && i < 8; i++)
 301                 free(envp[i]);
 302 }
 303
 304 bool dump_subnets(connection_t *c) {
 305         char netstr[MAXNETSTR];
 306         subnet_t *subnet;
 307         splay_node_t *node;
 308
 309         for(node = subnet_tree->head; node; node = node->next) {
 310                 subnet = node->data;
 311                 if(!net2str(netstr, sizeof netstr, subnet))
 312                         continue;
 313                 send_request(c, "%d %d %s owner %s",
 314                                 CONTROL, REQ_DUMP_SUBNETS,
 315                                 netstr, subnet->owner->name);
 316         }
 317
 318         return send_request(c, "%d %d", CONTROL, REQ_DUMP_SUBNETS);
 319 }