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 (*batadv_rx_handler[256])(struct sk_buff *,
  42                                      struct 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         /* the name should not be longer than 10 chars - see
  62          * http://lwn.net/Articles/23634/
  63          */
  64         batadv_event_workqueue = create_singlethread_workqueue("bat_events");
  65
  66         if (!batadv_event_workqueue)
  67                 return -ENOMEM;
  68
  69         batadv_socket_init();
  70         batadv_debugfs_init();
  71
  72         register_netdevice_notifier(&batadv_hard_if_notifier);
  73
  74         pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
  75                 BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
  76
  77         return 0;
  78 }
  79
  80 static void __exit batadv_exit(void)
  81 {
  82         batadv_debugfs_destroy();
  83         unregister_netdevice_notifier(&batadv_hard_if_notifier);
  84         batadv_hardif_remove_interfaces();
  85
  86         flush_workqueue(batadv_event_workqueue);
  87         destroy_workqueue(batadv_event_workqueue);
  88         batadv_event_workqueue = NULL;
  89
  90         rcu_barrier();
  91 }
  92
  93 int batadv_mesh_init(struct net_device *soft_iface)
  94 {
  95         struct bat_priv *bat_priv = netdev_priv(soft_iface);
  96         int ret;
  97
  98         spin_lock_init(&bat_priv->forw_bat_list_lock);
  99         spin_lock_init(&bat_priv->forw_bcast_list_lock);
 100         spin_lock_init(&bat_priv->tt_changes_list_lock);
 101         spin_lock_init(&bat_priv->tt_req_list_lock);
 102         spin_lock_init(&bat_priv->tt_roam_list_lock);
 103         spin_lock_init(&bat_priv->tt_buff_lock);
 104         spin_lock_init(&bat_priv->gw_list_lock);
 105         spin_lock_init(&bat_priv->vis_hash_lock);
 106         spin_lock_init(&bat_priv->vis_list_lock);
 107
 108         INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 109         INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 110         INIT_HLIST_HEAD(&bat_priv->gw_list);
 111         INIT_LIST_HEAD(&bat_priv->tt_changes_list);
 112         INIT_LIST_HEAD(&bat_priv->tt_req_list);
 113         INIT_LIST_HEAD(&bat_priv->tt_roam_list);
 114
 115         ret = batadv_originator_init(bat_priv);
 116         if (ret < 0)
 117                 goto err;
 118
 119         ret = batadv_tt_init(bat_priv);
 120         if (ret < 0)
 121                 goto err;
 122
 123         batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
 124                             BATADV_NULL_IFINDEX);
 125
 126         ret = batadv_vis_init(bat_priv);
 127         if (ret < 0)
 128                 goto err;
 129
 130         ret = batadv_bla_init(bat_priv);
 131         if (ret < 0)
 132                 goto err;
 133
 134         atomic_set(&bat_priv->gw_reselect, 0);
 135         atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
 136
 137         return 0;
 138
 139 err:
 140         batadv_mesh_free(soft_iface);
 141         return ret;
 142 }
 143
 144 void batadv_mesh_free(struct net_device *soft_iface)
 145 {
 146         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 147
 148         atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
 149
 150         batadv_purge_outstanding_packets(bat_priv, NULL);
 151
 152         batadv_vis_quit(bat_priv);
 153
 154         batadv_gw_node_purge(bat_priv);
 155         batadv_originator_free(bat_priv);
 156
 157         batadv_tt_free(bat_priv);
 158
 159         batadv_bla_free(bat_priv);
 160
 161         free_percpu(bat_priv->bat_counters);
 162
 163         atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
 164 }
 165
 166 void batadv_inc_module_count(void)
 167 {
 168         try_module_get(THIS_MODULE);
 169 }
 170
 171 void batadv_dec_module_count(void)
 172 {
 173         module_put(THIS_MODULE);
 174 }
 175
 176 int batadv_is_my_mac(const uint8_t *addr)
 177 {
 178         const struct hard_iface *hard_iface;
 179
 180         rcu_read_lock();
 181         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 182                 if (hard_iface->if_status != IF_ACTIVE)
 183                         continue;
 184
 185                 if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 186                         rcu_read_unlock();
 187                         return 1;
 188                 }
 189         }
 190         rcu_read_unlock();
 191         return 0;
 192 }
 193
 194 static int batadv_recv_unhandled_packet(struct sk_buff *skb,
 195                                         struct hard_iface *recv_if)
 196 {
 197         return NET_RX_DROP;
 198 }
 199
 200 /* incoming packets with the batman ethertype received on any active hard
 201  * interface
 202  */
 203 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 204                            struct packet_type *ptype,
 205                            struct net_device *orig_dev)
 206 {
 207         struct bat_priv *bat_priv;
 208         struct batman_ogm_packet *batman_ogm_packet;
 209         struct hard_iface *hard_iface;
 210         uint8_t idx;
 211         int ret;
 212
 213         hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype);
 214         skb = skb_share_check(skb, GFP_ATOMIC);
 215
 216         /* skb was released by skb_share_check() */
 217         if (!skb)
 218                 goto err_out;
 219
 220         /* packet should hold at least type and version */
 221         if (unlikely(!pskb_may_pull(skb, 2)))
 222                 goto err_free;
 223
 224         /* expect a valid ethernet header here. */
 225         if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
 226                 goto err_free;
 227
 228         if (!hard_iface->soft_iface)
 229                 goto err_free;
 230
 231         bat_priv = netdev_priv(hard_iface->soft_iface);
 232
 233         if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
 234                 goto err_free;
 235
 236         /* discard frames on not active interfaces */
 237         if (hard_iface->if_status != IF_ACTIVE)
 238                 goto err_free;
 239
 240         batman_ogm_packet = (struct batman_ogm_packet *)skb->data;
 241
 242         if (batman_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
 243                 batadv_dbg(DBG_BATMAN, bat_priv,
 244                            "Drop packet: incompatible batman version (%i)\n",
 245                            batman_ogm_packet->header.version);
 246                 goto err_free;
 247         }
 248
 249         /* all receive handlers return whether they received or reused
 250          * the supplied skb. if not, we have to free the skb.
 251          */
 252         idx = batman_ogm_packet->header.packet_type;
 253         ret = (*batadv_rx_handler[idx])(skb, hard_iface);
 254
 255         if (ret == NET_RX_DROP)
 256                 kfree_skb(skb);
 257
 258         /* return NET_RX_SUCCESS in any case as we
 259          * most probably dropped the packet for
 260          * routing-logical reasons.
 261          */
 262         return NET_RX_SUCCESS;
 263
 264 err_free:
 265         kfree_skb(skb);
 266 err_out:
 267         return NET_RX_DROP;
 268 }
 269
 270 static void batadv_recv_handler_init(void)
 271 {
 272         int i;
 273
 274         for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
 275                 batadv_rx_handler[i] = batadv_recv_unhandled_packet;
 276
 277         /* batman icmp packet */
 278         batadv_rx_handler[BAT_ICMP] = batadv_recv_icmp_packet;
 279         /* unicast packet */
 280         batadv_rx_handler[BAT_UNICAST] = batadv_recv_unicast_packet;
 281         /* fragmented unicast packet */
 282         batadv_rx_handler[BAT_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
 283         /* broadcast packet */
 284         batadv_rx_handler[BAT_BCAST] = batadv_recv_bcast_packet;
 285         /* vis packet */
 286         batadv_rx_handler[BAT_VIS] = batadv_recv_vis_packet;
 287         /* Translation table query (request or response) */
 288         batadv_rx_handler[BAT_TT_QUERY] = batadv_recv_tt_query;
 289         /* Roaming advertisement */
 290         batadv_rx_handler[BAT_ROAM_ADV] = batadv_recv_roam_adv;
 291 }
 292
 293 int batadv_recv_handler_register(uint8_t packet_type,
 294                                  int (*recv_handler)(struct sk_buff *,
 295                                                      struct hard_iface *))
 296 {
 297         if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
 298                 return -EBUSY;
 299
 300         batadv_rx_handler[packet_type] = recv_handler;
 301         return 0;
 302 }
 303
 304 void batadv_recv_handler_unregister(uint8_t packet_type)
 305 {
 306         batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
 307 }
 308
 309 static struct bat_algo_ops *batadv_algo_get(char *name)
 310 {
 311         struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
 312         struct hlist_node *node;
 313
 314         hlist_for_each_entry(bat_algo_ops_tmp, node, &batadv_algo_list, list) {
 315                 if (strcmp(bat_algo_ops_tmp->name, name) != 0)
 316                         continue;
 317
 318                 bat_algo_ops = bat_algo_ops_tmp;
 319                 break;
 320         }
 321
 322         return bat_algo_ops;
 323 }
 324
 325 int batadv_algo_register(struct bat_algo_ops *bat_algo_ops)
 326 {
 327         struct bat_algo_ops *bat_algo_ops_tmp;
 328         int ret;
 329
 330         bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name);
 331         if (bat_algo_ops_tmp) {
 332                 pr_info("Trying to register already registered routing algorithm: %s\n",
 333                         bat_algo_ops->name);
 334                 ret = -EEXIST;
 335                 goto out;
 336         }
 337
 338         /* all algorithms must implement all ops (for now) */
 339         if (!bat_algo_ops->bat_iface_enable ||
 340             !bat_algo_ops->bat_iface_disable ||
 341             !bat_algo_ops->bat_iface_update_mac ||
 342             !bat_algo_ops->bat_primary_iface_set ||
 343             !bat_algo_ops->bat_ogm_schedule ||
 344             !bat_algo_ops->bat_ogm_emit) {
 345                 pr_info("Routing algo '%s' does not implement required ops\n",
 346                         bat_algo_ops->name);
 347                 ret = -EINVAL;
 348                 goto out;
 349         }
 350
 351         INIT_HLIST_NODE(&bat_algo_ops->list);
 352         hlist_add_head(&bat_algo_ops->list, &batadv_algo_list);
 353         ret = 0;
 354
 355 out:
 356         return ret;
 357 }
 358
 359 int batadv_algo_select(struct bat_priv *bat_priv, char *name)
 360 {
 361         struct bat_algo_ops *bat_algo_ops;
 362         int ret = -EINVAL;
 363
 364         bat_algo_ops = batadv_algo_get(name);
 365         if (!bat_algo_ops)
 366                 goto out;
 367
 368         bat_priv->bat_algo_ops = bat_algo_ops;
 369         ret = 0;
 370
 371 out:
 372         return ret;
 373 }
 374
 375 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
 376 {
 377         struct bat_algo_ops *bat_algo_ops;
 378         struct hlist_node *node;
 379
 380         seq_printf(seq, "Available routing algorithms:\n");
 381
 382         hlist_for_each_entry(bat_algo_ops, node, &batadv_algo_list, list) {
 383                 seq_printf(seq, "%s\n", bat_algo_ops->name);
 384         }
 385
 386         return 0;
 387 }
 388
 389 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
 390 {
 391         struct bat_algo_ops *bat_algo_ops;
 392         char *algo_name = (char *)val;
 393         size_t name_len = strlen(algo_name);
 394
 395         if (algo_name[name_len - 1] == '\n')
 396                 algo_name[name_len - 1] = '\0';
 397
 398         bat_algo_ops = batadv_algo_get(algo_name);
 399         if (!bat_algo_ops) {
 400                 pr_err("Routing algorithm '%s' is not supported\n", algo_name);
 401                 return -EINVAL;
 402         }
 403
 404         return param_set_copystring(algo_name, kp);
 405 }
 406
 407 static const struct kernel_param_ops batadv_param_ops_ra = {
 408         .set = batadv_param_set_ra,
 409         .get = param_get_string,
 410 };
 411
 412 static struct kparam_string batadv_param_string_ra = {
 413         .maxlen = sizeof(batadv_routing_algo),
 414         .string = batadv_routing_algo,
 415 };
 416
 417 module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
 418                 0644);
 419 module_init(batadv_init);
 420 module_exit(batadv_exit);
 421
 422 MODULE_LICENSE("GPL");
 423
 424 MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
 425 MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
 426 MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
 427 MODULE_VERSION(BATADV_SOURCE_VERSION);