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 "hash.h"
  27 #include "logger.h"
  28 #include "net.h"
  29 #include "netutl.h"
  30 #include "node.h"
  31 #include "process.h"
  32 #include "subnet.h"
  33 #include "utils.h"
  34 #include "xalloc.h"
  35
  36 /* lists type of subnet */
  37
  38 splay_tree_t *subnet_tree;
  39
  40 /* Subnet lookup cache */
  41
  42 hash_t *ipv4_cache;
  43 hash_t *ipv6_cache;
  44 hash_t *mac_cache;
  45
  46 void subnet_cache_flush(void) {
  47         hash_clear(ipv4_cache);
  48         hash_clear(ipv6_cache);
  49         hash_clear(mac_cache);
  50 }
  51
  52 /* Initialising trees */
  53
  54 void init_subnets(void) {
  55         subnet_tree = splay_alloc_tree((splay_compare_t) subnet_compare, (splay_action_t) free_subnet);
  56
  57         ipv4_cache = hash_alloc(0x100, sizeof(ipv4_t));
  58         ipv6_cache = hash_alloc(0x100, sizeof(ipv6_t));
  59         mac_cache = hash_alloc(0x100, sizeof(mac_t));
  60 }
  61
  62 void exit_subnets(void) {
  63         splay_delete_tree(subnet_tree);
  64
  65         hash_free(ipv4_cache);
  66         hash_free(ipv6_cache);
  67         hash_free(mac_cache);
  68 }
  69
  70 splay_tree_t *new_subnet_tree(void) {
  71         return splay_alloc_tree((splay_compare_t) subnet_compare, NULL);
  72 }
  73
  74 void free_subnet_tree(splay_tree_t *subnet_tree) {
  75         splay_delete_tree(subnet_tree);
  76 }
  77
  78 /* Allocating and freeing space for subnets */
  79
  80 subnet_t *new_subnet(void) {
  81         return xmalloc_and_zero(sizeof(subnet_t));
  82 }
  83
  84 void free_subnet(subnet_t *subnet) {
  85         free(subnet);
  86 }
  87
  88 /* Adding and removing subnets */
  89
  90 void subnet_add(node_t *n, subnet_t *subnet) {
  91         subnet->owner = n;
  92
  93         splay_insert(subnet_tree, subnet);
  94         splay_insert(n->subnet_tree, subnet);
  95
  96         subnet_cache_flush();
  97 }
  98
  99 void subnet_del(node_t *n, subnet_t *subnet) {
 100         splay_delete(n->subnet_tree, subnet);
 101         splay_delete(subnet_tree, subnet);
 102
 103         subnet_cache_flush();
 104 }
 105
 106 /* Subnet lookup routines */
 107
 108 subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) {
 109         return splay_search(owner->subnet_tree, subnet);
 110 }
 111
 112 subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
 113         subnet_t *p, *r = NULL;
 114         splay_node_t *n;
 115
 116         // Check if this address is cached
 117
 118         if((r = hash_search(mac_cache, address)))
 119                 return r;
 120
 121         // Search all subnets for a matching one
 122
 123         for(n = owner ? owner->subnet_tree->head : subnet_tree->head; n; n = n->next) {
 124                 p = n->data;
 125
 126                 if(!p || p->type != SUBNET_MAC)
 127                         continue;
 128
 129                 if(!memcmp(address, &p->net.mac.address, sizeof *address)) {
 130                         r = p;
 131                         if(p->owner->status.reachable)
 132                                 break;
 133                 }
 134         }
 135
 136         // Cache the result
 137
 138         if(r)
 139                 hash_insert(mac_cache, address, r);
 140
 141         return r;
 142 }
 143
 144 subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
 145         subnet_t *p, *r = NULL;
 146         splay_node_t *n;
 147
 148         // Check if this address is cached
 149
 150         if((r = hash_search(ipv4_cache, address)))
 151                 return r;
 152
 153         // Search all subnets for a matching one
 154
 155         for(n = subnet_tree->head; n; n = n->next) {
 156                 p = n->data;
 157
 158                 if(!p || p->type != SUBNET_IPV4)
 159                         continue;
 160
 161                 if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength)) {
 162                         r = p;
 163                         if(p->owner->status.reachable)
 164                                 break;
 165                 }
 166         }
 167
 168         // Cache the result
 169
 170         if(r)
 171                 hash_insert(ipv4_cache, address, r);
 172
 173         return r;
 174 }
 175
 176 subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
 177         subnet_t *p, *r = NULL;
 178         splay_node_t *n;
 179
 180         // Check if this address is cached
 181
 182         if((r = hash_search(ipv6_cache, address)))
 183                 return r;
 184
 185         // Search all subnets for a matching one
 186
 187         for(n = subnet_tree->head; n; n = n->next) {
 188                 p = n->data;
 189
 190                 if(!p || p->type != SUBNET_IPV6)
 191                         continue;
 192
 193                 if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength)) {
 194                         r = p;
 195                         if(p->owner->status.reachable)
 196                                 break;
 197                 }
 198         }
 199
 200         // Cache the result
 201
 202         if(r)
 203                 hash_insert(ipv6_cache, address, r);
 204
 205         return r;
 206 }
 207
 208 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 209         splay_node_t *node;
 210         int i;
 211         char *envp[9] = {NULL};
 212         char netstr[MAXNETSTR];
 213         char *name, *address, *port;
 214         char empty[] = "";
 215
 216         // Prepare environment variables to be passed to the script
 217
 218         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 219         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 220         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 221         xasprintf(&envp[3], "NODE=%s", owner->name);
 222
 223         if(owner != myself) {
 224                 sockaddr2str(&owner->address, &address, &port);
 225                 // 4 and 5 are reserved for SUBNET and WEIGHT
 226                 xasprintf(&envp[6], "REMOTEADDRESS=%s", address);
 227                 xasprintf(&envp[7], "REMOTEPORT=%s", port);
 228                 free(port);
 229                 free(address);
 230         }
 231
 232         name = up ? "subnet-up" : "subnet-down";
 233
 234         if(!subnet) {
 235                 for(node = owner->subnet_tree->head; node; node = node->next) {
 236                         subnet = node->data;
 237                         if(!net2str(netstr, sizeof netstr, subnet))
 238                                 continue;
 239                         // Strip the weight from the subnet, and put it in its own environment variable
 240                         char *weight = strchr(netstr, '#');
 241                         if(weight)
 242                                 *weight++ = 0;
 243                         else
 244                                 weight = empty;
 245
 246                         // Prepare the SUBNET and WEIGHT variables
 247                         if(envp[4])
 248                                 free(envp[4]);
 249                         if(envp[5])
 250                                 free(envp[5]);
 251                         xasprintf(&envp[4], "SUBNET=%s", netstr);
 252                         xasprintf(&envp[5], "WEIGHT=%s", weight);
 253
 254                         execute_script(name, envp);
 255                 }
 256         } else {
 257                 if(net2str(netstr, sizeof netstr, subnet)) {
 258                         // Strip the weight from the subnet, and put it in its own environment variable
 259                         char *weight = strchr(netstr, '#');
 260                         if(weight)
 261                                 *weight++ = 0;
 262                         else
 263                                 weight = empty;
 264
 265                         // Prepare the SUBNET and WEIGHT variables
 266                         xasprintf(&envp[4], "SUBNET=%s", netstr);
 267                         xasprintf(&envp[5], "WEIGHT=%s", weight);
 268
 269                         execute_script(name, envp);
 270                 }
 271         }
 272
 273         for(i = 0; envp[i] && i < 8; i++)
 274                 free(envp[i]);
 275 }
 276
 277 bool dump_subnets(connection_t *c) {
 278         char netstr[MAXNETSTR];
 279         subnet_t *subnet;
 280         splay_node_t *node;
 281
 282         for(node = subnet_tree->head; node; node = node->next) {
 283                 subnet = node->data;
 284                 if(!net2str(netstr, sizeof netstr, subnet))
 285                         continue;
 286                 send_request(c, "%d %d %s owner %s",
 287                                 CONTROL, REQ_DUMP_SUBNETS,
 288                                 netstr, subnet->owner->name);
 289         }
 290
 291         return send_request(c, "%d %d", CONTROL, REQ_DUMP_SUBNETS);
 292 }