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 "bat_sysfs.h"
  22 #include "bat_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 (*recv_packet_handler[256])(struct sk_buff *, struct hard_iface *);
  42 char batadv_routing_algo[20] = "BATMAN_IV";
  43 static struct hlist_head bat_algo_list;
  44
  45 unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  46
  47 struct workqueue_struct *batadv_event_workqueue;
  48
  49 static void recv_handler_init(void);
  50
  51 static int __init batman_init(void)
  52 {
  53         INIT_LIST_HEAD(&batadv_hardif_list);
  54         INIT_HLIST_HEAD(&bat_algo_list);
  55
  56         recv_handler_init();
  57
  58         batadv_iv_init();
  59
  60         /* the name should not be longer than 10 chars - see
  61          * http://lwn.net/Articles/23634/
  62          */
  63         batadv_event_workqueue = create_singlethread_workqueue("bat_events");
  64
  65         if (!batadv_event_workqueue)
  66                 return -ENOMEM;
  67
  68         batadv_socket_init();
  69         batadv_debugfs_init();
  70
  71         register_netdevice_notifier(&batadv_hard_if_notifier);
  72
  73         pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
  74                 SOURCE_VERSION, COMPAT_VERSION);
  75
  76         return 0;
  77 }
  78
  79 static void __exit batman_exit(void)
  80 {
  81         batadv_debugfs_destroy();
  82         unregister_netdevice_notifier(&batadv_hard_if_notifier);
  83         batadv_hardif_remove_interfaces();
  84
  85         flush_workqueue(batadv_event_workqueue);
  86         destroy_workqueue(batadv_event_workqueue);
  87         batadv_event_workqueue = NULL;
  88
  89         rcu_barrier();
  90 }
  91
  92 int batadv_mesh_init(struct net_device *soft_iface)
  93 {
  94         struct bat_priv *bat_priv = netdev_priv(soft_iface);
  95         int ret;
  96
  97         spin_lock_init(&bat_priv->forw_bat_list_lock);
  98         spin_lock_init(&bat_priv->forw_bcast_list_lock);
  99         spin_lock_init(&bat_priv->tt_changes_list_lock);
 100         spin_lock_init(&bat_priv->tt_req_list_lock);
 101         spin_lock_init(&bat_priv->tt_roam_list_lock);
 102         spin_lock_init(&bat_priv->tt_buff_lock);
 103         spin_lock_init(&bat_priv->gw_list_lock);
 104         spin_lock_init(&bat_priv->vis_hash_lock);
 105         spin_lock_init(&bat_priv->vis_list_lock);
 106
 107         INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 108         INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 109         INIT_HLIST_HEAD(&bat_priv->gw_list);
 110         INIT_LIST_HEAD(&bat_priv->tt_changes_list);
 111         INIT_LIST_HEAD(&bat_priv->tt_req_list);
 112         INIT_LIST_HEAD(&bat_priv->tt_roam_list);
 113
 114         ret = batadv_originator_init(bat_priv);
 115         if (ret < 0)
 116                 goto err;
 117
 118         ret = batadv_tt_init(bat_priv);
 119         if (ret < 0)
 120                 goto err;
 121
 122         batadv_tt_local_add(soft_iface, soft_iface->dev_addr, NULL_IFINDEX);
 123
 124         ret = batadv_vis_init(bat_priv);
 125         if (ret < 0)
 126                 goto err;
 127
 128         ret = batadv_bla_init(bat_priv);
 129         if (ret < 0)
 130                 goto err;
 131
 132         atomic_set(&bat_priv->gw_reselect, 0);
 133         atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
 134
 135         return 0;
 136
 137 err:
 138         batadv_mesh_free(soft_iface);
 139         return ret;
 140 }
 141
 142 void batadv_mesh_free(struct net_device *soft_iface)
 143 {
 144         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 145
 146         atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
 147
 148         batadv_purge_outstanding_packets(bat_priv, NULL);
 149
 150         batadv_vis_quit(bat_priv);
 151
 152         batadv_gw_node_purge(bat_priv);
 153         batadv_originator_free(bat_priv);
 154
 155         batadv_tt_free(bat_priv);
 156
 157         batadv_bla_free(bat_priv);
 158
 159         free_percpu(bat_priv->bat_counters);
 160
 161         atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
 162 }
 163
 164 void batadv_inc_module_count(void)
 165 {
 166         try_module_get(THIS_MODULE);
 167 }
 168
 169 void batadv_dec_module_count(void)
 170 {
 171         module_put(THIS_MODULE);
 172 }
 173
 174 int batadv_is_my_mac(const uint8_t *addr)
 175 {
 176         const struct hard_iface *hard_iface;
 177
 178         rcu_read_lock();
 179         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 180                 if (hard_iface->if_status != IF_ACTIVE)
 181                         continue;
 182
 183                 if (compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 184                         rcu_read_unlock();
 185                         return 1;
 186                 }
 187         }
 188         rcu_read_unlock();
 189         return 0;
 190 }
 191
 192 static int recv_unhandled_packet(struct sk_buff *skb,
 193                                  struct hard_iface *recv_if)
 194 {
 195         return NET_RX_DROP;
 196 }
 197
 198 /* incoming packets with the batman ethertype received on any active hard
 199  * interface
 200  */
 201 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 202                            struct packet_type *ptype,
 203                            struct net_device *orig_dev)
 204 {
 205         struct bat_priv *bat_priv;
 206         struct batman_ogm_packet *batman_ogm_packet;
 207         struct hard_iface *hard_iface;
 208         uint8_t idx;
 209         int ret;
 210
 211         hard_iface = container_of(ptype, struct hard_iface, 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) != MESH_ACTIVE)
 232                 goto err_free;
 233
 234         /* discard frames on not active interfaces */
 235         if (hard_iface->if_status != IF_ACTIVE)
 236                 goto err_free;
 237
 238         batman_ogm_packet = (struct batman_ogm_packet *)skb->data;
 239
 240         if (batman_ogm_packet->header.version != COMPAT_VERSION) {
 241                 bat_dbg(DBG_BATMAN, bat_priv,
 242                         "Drop packet: incompatible batman version (%i)\n",
 243                         batman_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 = batman_ogm_packet->header.packet_type;
 251         ret = (*recv_packet_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 recv_handler_init(void)
 269 {
 270         int i;
 271
 272         for (i = 0; i < ARRAY_SIZE(recv_packet_handler); i++)
 273                 recv_packet_handler[i] = recv_unhandled_packet;
 274
 275         /* batman icmp packet */
 276         recv_packet_handler[BAT_ICMP] = batadv_recv_icmp_packet;
 277         /* unicast packet */
 278         recv_packet_handler[BAT_UNICAST] = batadv_recv_unicast_packet;
 279         /* fragmented unicast packet */
 280         recv_packet_handler[BAT_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
 281         /* broadcast packet */
 282         recv_packet_handler[BAT_BCAST] = batadv_recv_bcast_packet;
 283         /* vis packet */
 284         recv_packet_handler[BAT_VIS] = batadv_recv_vis_packet;
 285         /* Translation table query (request or response) */
 286         recv_packet_handler[BAT_TT_QUERY] = batadv_recv_tt_query;
 287         /* Roaming advertisement */
 288         recv_packet_handler[BAT_ROAM_ADV] = batadv_recv_roam_adv;
 289 }
 290
 291 int batadv_recv_handler_register(uint8_t packet_type,
 292                                  int (*recv_handler)(struct sk_buff *,
 293                                                      struct hard_iface *))
 294 {
 295         if (recv_packet_handler[packet_type] != &recv_unhandled_packet)
 296                 return -EBUSY;
 297
 298         recv_packet_handler[packet_type] = recv_handler;
 299         return 0;
 300 }
 301
 302 void batadv_recv_handler_unregister(uint8_t packet_type)
 303 {
 304         recv_packet_handler[packet_type] = recv_unhandled_packet;
 305 }
 306
 307 static struct bat_algo_ops *bat_algo_get(char *name)
 308 {
 309         struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
 310         struct hlist_node *node;
 311
 312         hlist_for_each_entry(bat_algo_ops_tmp, node, &bat_algo_list, list) {
 313                 if (strcmp(bat_algo_ops_tmp->name, name) != 0)
 314                         continue;
 315
 316                 bat_algo_ops = bat_algo_ops_tmp;
 317                 break;
 318         }
 319
 320         return bat_algo_ops;
 321 }
 322
 323 int batadv_algo_register(struct bat_algo_ops *bat_algo_ops)
 324 {
 325         struct bat_algo_ops *bat_algo_ops_tmp;
 326         int ret;
 327
 328         bat_algo_ops_tmp = bat_algo_get(bat_algo_ops->name);
 329         if (bat_algo_ops_tmp) {
 330                 pr_info("Trying to register already registered routing algorithm: %s\n",
 331                         bat_algo_ops->name);
 332                 ret = -EEXIST;
 333                 goto out;
 334         }
 335
 336         /* all algorithms must implement all ops (for now) */
 337         if (!bat_algo_ops->bat_iface_enable ||
 338             !bat_algo_ops->bat_iface_disable ||
 339             !bat_algo_ops->bat_iface_update_mac ||
 340             !bat_algo_ops->bat_primary_iface_set ||
 341             !bat_algo_ops->bat_ogm_schedule ||
 342             !bat_algo_ops->bat_ogm_emit) {
 343                 pr_info("Routing algo '%s' does not implement required ops\n",
 344                         bat_algo_ops->name);
 345                 ret = -EINVAL;
 346                 goto out;
 347         }
 348
 349         INIT_HLIST_NODE(&bat_algo_ops->list);
 350         hlist_add_head(&bat_algo_ops->list, &bat_algo_list);
 351         ret = 0;
 352
 353 out:
 354         return ret;
 355 }
 356
 357 int batadv_algo_select(struct bat_priv *bat_priv, char *name)
 358 {
 359         struct bat_algo_ops *bat_algo_ops;
 360         int ret = -EINVAL;
 361
 362         bat_algo_ops = bat_algo_get(name);
 363         if (!bat_algo_ops)
 364                 goto out;
 365
 366         bat_priv->bat_algo_ops = bat_algo_ops;
 367         ret = 0;
 368
 369 out:
 370         return ret;
 371 }
 372
 373 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
 374 {
 375         struct bat_algo_ops *bat_algo_ops;
 376         struct hlist_node *node;
 377
 378         seq_printf(seq, "Available routing algorithms:\n");
 379
 380         hlist_for_each_entry(bat_algo_ops, node, &bat_algo_list, list) {
 381                 seq_printf(seq, "%s\n", bat_algo_ops->name);
 382         }
 383
 384         return 0;
 385 }
 386
 387 static int param_set_ra(const char *val, const struct kernel_param *kp)
 388 {
 389         struct bat_algo_ops *bat_algo_ops;
 390         char *algo_name = (char *)val;
 391         size_t name_len = strlen(algo_name);
 392
 393         if (algo_name[name_len - 1] == '\n')
 394                 algo_name[name_len - 1] = '\0';
 395
 396         bat_algo_ops = bat_algo_get(algo_name);
 397         if (!bat_algo_ops) {
 398                 pr_err("Routing algorithm '%s' is not supported\n", algo_name);
 399                 return -EINVAL;
 400         }
 401
 402         return param_set_copystring(algo_name, kp);
 403 }
 404
 405 static const struct kernel_param_ops param_ops_ra = {
 406         .set = param_set_ra,
 407         .get = param_get_string,
 408 };
 409
 410 static struct kparam_string __param_string_ra = {
 411         .maxlen = sizeof(batadv_routing_algo),
 412         .string = batadv_routing_algo,
 413 };
 414
 415 module_param_cb(routing_algo, &param_ops_ra, &__param_string_ra, 0644);
 416 module_init(batman_init);
 417 module_exit(batman_exit);
 418
 419 MODULE_LICENSE("GPL");
 420
 421 MODULE_AUTHOR(DRIVER_AUTHOR);
 422 MODULE_DESCRIPTION(DRIVER_DESC);
 423 MODULE_SUPPORTED_DEVICE(DRIVER_DEVICE);
 424 MODULE_VERSION(SOURCE_VERSION);