net/batman-adv/main.c

   1 /* Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, Simon Wunderlich
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA
  18  */
  19
  20 #include "main.h"
  21 #include "sysfs.h"
  22 #include "debugfs.h"
  23 #include "routing.h"
  24 #include "send.h"
  25 #include "originator.h"
  26 #include "soft-interface.h"
  27 #include "icmp_socket.h"
  28 #include "translation-table.h"
  29 #include "hard-interface.h"
  30 #include "gateway_client.h"
  31 #include "bridge_loop_avoidance.h"
  32 #include "vis.h"
  33 #include "hash.h"
  34 #include "bat_algo.h"
  35
  36
  37 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
  38  * list traversals just rcu-locked
  39  */
  40 struct list_head batadv_hardif_list;
  41 static int (*batadv_rx_handler[256])(struct sk_buff *,
  42                                      struct batadv_hard_iface *);
  43 char batadv_routing_algo[20] = "BATMAN_IV";
  44 static struct hlist_head batadv_algo_list;
  45
  46 unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  47
  48 struct workqueue_struct *batadv_event_workqueue;
  49
  50 static void batadv_recv_handler_init(void);
  51
  52 static int __init batadv_init(void)
  53 {
  54         INIT_LIST_HEAD(&batadv_hardif_list);
  55         INIT_HLIST_HEAD(&batadv_algo_list);
  56
  57         batadv_recv_handler_init();
  58
  59         batadv_iv_init();
  60
  61         batadv_event_workqueue = create_singlethread_workqueue("bat_events");
  62
  63         if (!batadv_event_workqueue)
  64                 return -ENOMEM;
  65
  66         batadv_socket_init();
  67         batadv_debugfs_init();
  68
  69         register_netdevice_notifier(&batadv_hard_if_notifier);
  70
  71         pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
  72                 BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
  73
  74         return 0;
  75 }
  76
  77 static void __exit batadv_exit(void)
  78 {
  79         batadv_debugfs_destroy();
  80         unregister_netdevice_notifier(&batadv_hard_if_notifier);
  81         batadv_hardif_remove_interfaces();
  82
  83         flush_workqueue(batadv_event_workqueue);
  84         destroy_workqueue(batadv_event_workqueue);
  85         batadv_event_workqueue = NULL;
  86
  87         rcu_barrier();
  88 }
  89
  90 int batadv_mesh_init(struct net_device *soft_iface)
  91 {
  92         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
  93         int ret;
  94
  95         spin_lock_init(&bat_priv->forw_bat_list_lock);
  96         spin_lock_init(&bat_priv->forw_bcast_list_lock);
  97         spin_lock_init(&bat_priv->tt.changes_list_lock);
  98         spin_lock_init(&bat_priv->tt.req_list_lock);
  99         spin_lock_init(&bat_priv->tt.roam_list_lock);
 100         spin_lock_init(&bat_priv->tt.last_changeset_lock);
 101         spin_lock_init(&bat_priv->gw.list_lock);
 102         spin_lock_init(&bat_priv->vis.hash_lock);
 103         spin_lock_init(&bat_priv->vis.list_lock);
 104
 105         INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 106         INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 107         INIT_HLIST_HEAD(&bat_priv->gw.list);
 108         INIT_LIST_HEAD(&bat_priv->tt.changes_list);
 109         INIT_LIST_HEAD(&bat_priv->tt.req_list);
 110         INIT_LIST_HEAD(&bat_priv->tt.roam_list);
 111
 112         ret = batadv_originator_init(bat_priv);
 113         if (ret < 0)
 114                 goto err;
 115
 116         ret = batadv_tt_init(bat_priv);
 117         if (ret < 0)
 118                 goto err;
 119
 120         batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
 121                             BATADV_NULL_IFINDEX);
 122
 123         ret = batadv_vis_init(bat_priv);
 124         if (ret < 0)
 125                 goto err;
 126
 127         ret = batadv_bla_init(bat_priv);
 128         if (ret < 0)
 129                 goto err;
 130
 131         atomic_set(&bat_priv->gw.reselect, 0);
 132         atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 133
 134         return 0;
 135
 136 err:
 137         batadv_mesh_free(soft_iface);
 138         return ret;
 139 }
 140
 141 void batadv_mesh_free(struct net_device *soft_iface)
 142 {
 143         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 144
 145         atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
 146
 147         batadv_purge_outstanding_packets(bat_priv, NULL);
 148
 149         batadv_vis_quit(bat_priv);
 150
 151         batadv_gw_node_purge(bat_priv);
 152         batadv_originator_free(bat_priv);
 153
 154         batadv_tt_free(bat_priv);
 155
 156         batadv_bla_free(bat_priv);
 157
 158         free_percpu(bat_priv->bat_counters);
 159
 160         atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 161 }
 162
 163 void batadv_inc_module_count(void)
 164 {
 165         try_module_get(THIS_MODULE);
 166 }
 167
 168 void batadv_dec_module_count(void)
 169 {
 170         module_put(THIS_MODULE);
 171 }
 172
 173 int batadv_is_my_mac(const uint8_t *addr)
 174 {
 175         const struct batadv_hard_iface *hard_iface;
 176
 177         rcu_read_lock();
 178         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 179                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
 180                         continue;
 181
 182                 if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 183                         rcu_read_unlock();
 184                         return 1;
 185                 }
 186         }
 187         rcu_read_unlock();
 188         return 0;
 189 }
 190
 191 static int batadv_recv_unhandled_packet(struct sk_buff *skb,
 192                                         struct batadv_hard_iface *recv_if)
 193 {
 194         return NET_RX_DROP;
 195 }
 196
 197 /* incoming packets with the batman ethertype received on any active hard
 198  * interface
 199  */
 200 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 201                            struct packet_type *ptype,
 202                            struct net_device *orig_dev)
 203 {
 204         struct batadv_priv *bat_priv;
 205         struct batadv_ogm_packet *batadv_ogm_packet;
 206         struct batadv_hard_iface *hard_iface;
 207         uint8_t idx;
 208         int ret;
 209
 210         hard_iface = container_of(ptype, struct batadv_hard_iface,
 211                                   batman_adv_ptype);
 212         skb = skb_share_check(skb, GFP_ATOMIC);
 213
 214         /* skb was released by skb_share_check() */
 215         if (!skb)
 216                 goto err_out;
 217
 218         /* packet should hold at least type and version */
 219         if (unlikely(!pskb_may_pull(skb, 2)))
 220                 goto err_free;
 221
 222         /* expect a valid ethernet header here. */
 223         if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
 224                 goto err_free;
 225
 226         if (!hard_iface->soft_iface)
 227                 goto err_free;
 228
 229         bat_priv = netdev_priv(hard_iface->soft_iface);
 230
 231         if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 232                 goto err_free;
 233
 234         /* discard frames on not active interfaces */
 235         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 236                 goto err_free;
 237
 238         batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;
 239
 240         if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
 241                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 242                            "Drop packet: incompatible batman version (%i)\n",
 243                            batadv_ogm_packet->header.version);
 244                 goto err_free;
 245         }
 246
 247         /* all receive handlers return whether they received or reused
 248          * the supplied skb. if not, we have to free the skb.
 249          */
 250         idx = batadv_ogm_packet->header.packet_type;
 251         ret = (*batadv_rx_handler[idx])(skb, hard_iface);
 252
 253         if (ret == NET_RX_DROP)
 254                 kfree_skb(skb);
 255
 256         /* return NET_RX_SUCCESS in any case as we
 257          * most probably dropped the packet for
 258          * routing-logical reasons.
 259          */
 260         return NET_RX_SUCCESS;
 261
 262 err_free:
 263         kfree_skb(skb);
 264 err_out:
 265         return NET_RX_DROP;
 266 }
 267
 268 static void batadv_recv_handler_init(void)
 269 {
 270         int i;
 271
 272         for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
 273                 batadv_rx_handler[i] = batadv_recv_unhandled_packet;
 274
 275         /* batman icmp packet */
 276         batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
 277         /* unicast packet */
 278         batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
 279         /* fragmented unicast packet */
 280         batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
 281         /* broadcast packet */
 282         batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
 283         /* vis packet */
 284         batadv_rx_handler[BATADV_VIS] = batadv_recv_vis_packet;
 285         /* Translation table query (request or response) */
 286         batadv_rx_handler[BATADV_TT_QUERY] = batadv_recv_tt_query;
 287         /* Roaming advertisement */
 288         batadv_rx_handler[BATADV_ROAM_ADV] = batadv_recv_roam_adv;
 289 }
 290
 291 int
 292 batadv_recv_handler_register(uint8_t packet_type,
 293                              int (*recv_handler)(struct sk_buff *,
 294                                                  struct batadv_hard_iface *))
 295 {
 296         if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
 297                 return -EBUSY;
 298
 299         batadv_rx_handler[packet_type] = recv_handler;
 300         return 0;
 301 }
 302
 303 void batadv_recv_handler_unregister(uint8_t packet_type)
 304 {
 305         batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
 306 }
 307
 308 static struct batadv_algo_ops *batadv_algo_get(char *name)
 309 {
 310         struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
 311         struct hlist_node *node;
 312
 313         hlist_for_each_entry(bat_algo_ops_tmp, node, &batadv_algo_list, list) {
 314                 if (strcmp(bat_algo_ops_tmp->name, name) != 0)
 315                         continue;
 316
 317                 bat_algo_ops = bat_algo_ops_tmp;
 318                 break;
 319         }
 320
 321         return bat_algo_ops;
 322 }
 323
 324 int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops)
 325 {
 326         struct batadv_algo_ops *bat_algo_ops_tmp;
 327         int ret;
 328
 329         bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name);
 330         if (bat_algo_ops_tmp) {
 331                 pr_info("Trying to register already registered routing algorithm: %s\n",
 332                         bat_algo_ops->name);
 333                 ret = -EEXIST;
 334                 goto out;
 335         }
 336
 337         /* all algorithms must implement all ops (for now) */
 338         if (!bat_algo_ops->bat_iface_enable ||
 339             !bat_algo_ops->bat_iface_disable ||
 340             !bat_algo_ops->bat_iface_update_mac ||
 341             !bat_algo_ops->bat_primary_iface_set ||
 342             !bat_algo_ops->bat_ogm_schedule ||
 343             !bat_algo_ops->bat_ogm_emit) {
 344                 pr_info("Routing algo '%s' does not implement required ops\n",
 345                         bat_algo_ops->name);
 346                 ret = -EINVAL;
 347                 goto out;
 348         }
 349
 350         INIT_HLIST_NODE(&bat_algo_ops->list);
 351         hlist_add_head(&bat_algo_ops->list, &batadv_algo_list);
 352         ret = 0;
 353
 354 out:
 355         return ret;
 356 }
 357
 358 int batadv_algo_select(struct batadv_priv *bat_priv, char *name)
 359 {
 360         struct batadv_algo_ops *bat_algo_ops;
 361         int ret = -EINVAL;
 362
 363         bat_algo_ops = batadv_algo_get(name);
 364         if (!bat_algo_ops)
 365                 goto out;
 366
 367         bat_priv->bat_algo_ops = bat_algo_ops;
 368         ret = 0;
 369
 370 out:
 371         return ret;
 372 }
 373
 374 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
 375 {
 376         struct batadv_algo_ops *bat_algo_ops;
 377         struct hlist_node *node;
 378
 379         seq_printf(seq, "Available routing algorithms:\n");
 380
 381         hlist_for_each_entry(bat_algo_ops, node, &batadv_algo_list, list) {
 382                 seq_printf(seq, "%s\n", bat_algo_ops->name);
 383         }
 384
 385         return 0;
 386 }
 387
 388 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
 389 {
 390         struct batadv_algo_ops *bat_algo_ops;
 391         char *algo_name = (char *)val;
 392         size_t name_len = strlen(algo_name);
 393
 394         if (algo_name[name_len - 1] == '\n')
 395                 algo_name[name_len - 1] = '\0';
 396
 397         bat_algo_ops = batadv_algo_get(algo_name);
 398         if (!bat_algo_ops) {
 399                 pr_err("Routing algorithm '%s' is not supported\n", algo_name);
 400                 return -EINVAL;
 401         }
 402
 403         return param_set_copystring(algo_name, kp);
 404 }
 405
 406 static const struct kernel_param_ops batadv_param_ops_ra = {
 407         .set = batadv_param_set_ra,
 408         .get = param_get_string,
 409 };
 410
 411 static struct kparam_string batadv_param_string_ra = {
 412         .maxlen = sizeof(batadv_routing_algo),
 413         .string = batadv_routing_algo,
 414 };
 415
 416 module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
 417                 0644);
 418 module_init(batadv_init);
 419 module_exit(batadv_exit);
 420
 421 MODULE_LICENSE("GPL");
 422
 423 MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
 424 MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
 425 MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
 426 MODULE_VERSION(BATADV_SOURCE_VERSION);