net/batman-adv/main.c

   1 /*
   2  * Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "bat_sysfs.h"
  24 #include "bat_debugfs.h"
  25 #include "routing.h"
  26 #include "send.h"
  27 #include "originator.h"
  28 #include "soft-interface.h"
  29 #include "icmp_socket.h"
  30 #include "translation-table.h"
  31 #include "hard-interface.h"
  32 #include "gateway_client.h"
  33 #include "bridge_loop_avoidance.h"
  34 #include "vis.h"
  35 #include "hash.h"
  36 #include "bat_algo.h"
  37
  38
  39 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
  40  * list traversals just rcu-locked */
  41 struct list_head hardif_list;
  42 static int (*recv_packet_handler[256])(struct sk_buff *, struct hard_iface *);
  43 char bat_routing_algo[20] = "BATMAN_IV";
  44 static struct hlist_head bat_algo_list;
  45
  46 unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  47
  48 struct workqueue_struct *bat_event_workqueue;
  49
  50 static void recv_handler_init(void);
  51
  52 static int __init batman_init(void)
  53 {
  54         INIT_LIST_HEAD(&hardif_list);
  55         INIT_HLIST_HEAD(&bat_algo_list);
  56
  57         recv_handler_init();
  58
  59         bat_iv_init();
  60
  61         /* the name should not be longer than 10 chars - see
  62          * http://lwn.net/Articles/23634/ */
  63         bat_event_workqueue = create_singlethread_workqueue("bat_events");
  64
  65         if (!bat_event_workqueue)
  66                 return -ENOMEM;
  67
  68         bat_socket_init();
  69         debugfs_init();
  70
  71         register_netdevice_notifier(&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         debugfs_destroy();
  82         unregister_netdevice_notifier(&hard_if_notifier);
  83         hardif_remove_interfaces();
  84
  85         flush_workqueue(bat_event_workqueue);
  86         destroy_workqueue(bat_event_workqueue);
  87         bat_event_workqueue = NULL;
  88
  89         rcu_barrier();
  90 }
  91
  92 int mesh_init(struct net_device *soft_iface)
  93 {
  94         struct bat_priv *bat_priv = netdev_priv(soft_iface);
  95
  96         spin_lock_init(&bat_priv->forw_bat_list_lock);
  97         spin_lock_init(&bat_priv->forw_bcast_list_lock);
  98         spin_lock_init(&bat_priv->tt_changes_list_lock);
  99         spin_lock_init(&bat_priv->tt_req_list_lock);
 100         spin_lock_init(&bat_priv->tt_roam_list_lock);
 101         spin_lock_init(&bat_priv->tt_buff_lock);
 102         spin_lock_init(&bat_priv->gw_list_lock);
 103         spin_lock_init(&bat_priv->vis_hash_lock);
 104         spin_lock_init(&bat_priv->vis_list_lock);
 105
 106         INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 107         INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 108         INIT_HLIST_HEAD(&bat_priv->gw_list);
 109         INIT_LIST_HEAD(&bat_priv->tt_changes_list);
 110         INIT_LIST_HEAD(&bat_priv->tt_req_list);
 111         INIT_LIST_HEAD(&bat_priv->tt_roam_list);
 112
 113         if (originator_init(bat_priv) < 1)
 114                 goto err;
 115
 116         if (tt_init(bat_priv) < 1)
 117                 goto err;
 118
 119         tt_local_add(soft_iface, soft_iface->dev_addr, NULL_IFINDEX);
 120
 121         if (vis_init(bat_priv) < 1)
 122                 goto err;
 123
 124         if (bla_init(bat_priv) < 1)
 125                 goto err;
 126
 127         atomic_set(&bat_priv->gw_reselect, 0);
 128         atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
 129         goto end;
 130
 131 err:
 132         mesh_free(soft_iface);
 133         return -1;
 134
 135 end:
 136         return 0;
 137 }
 138
 139 void mesh_free(struct net_device *soft_iface)
 140 {
 141         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 142
 143         atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
 144
 145         purge_outstanding_packets(bat_priv, NULL);
 146
 147         vis_quit(bat_priv);
 148
 149         gw_node_purge(bat_priv);
 150         originator_free(bat_priv);
 151
 152         tt_free(bat_priv);
 153
 154         bla_free(bat_priv);
 155
 156         free_percpu(bat_priv->bat_counters);
 157
 158         atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
 159 }
 160
 161 void inc_module_count(void)
 162 {
 163         try_module_get(THIS_MODULE);
 164 }
 165
 166 void dec_module_count(void)
 167 {
 168         module_put(THIS_MODULE);
 169 }
 170
 171 int is_my_mac(const uint8_t *addr)
 172 {
 173         const struct hard_iface *hard_iface;
 174
 175         rcu_read_lock();
 176         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 177                 if (hard_iface->if_status != IF_ACTIVE)
 178                         continue;
 179
 180                 if (compare_eth(hard_iface->net_dev->dev_addr, addr)) {
 181                         rcu_read_unlock();
 182                         return 1;
 183                 }
 184         }
 185         rcu_read_unlock();
 186         return 0;
 187 }
 188
 189 static int recv_unhandled_packet(struct sk_buff *skb,
 190                                  struct hard_iface *recv_if)
 191 {
 192         return NET_RX_DROP;
 193 }
 194
 195 /* incoming packets with the batman ethertype received on any active hard
 196  * interface
 197  */
 198 int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 199                     struct packet_type *ptype, struct net_device *orig_dev)
 200 {
 201         struct bat_priv *bat_priv;
 202         struct batman_ogm_packet *batman_ogm_packet;
 203         struct hard_iface *hard_iface;
 204         uint8_t idx;
 205         int ret;
 206
 207         hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype);
 208         skb = skb_share_check(skb, GFP_ATOMIC);
 209
 210         /* skb was released by skb_share_check() */
 211         if (!skb)
 212                 goto err_out;
 213
 214         /* packet should hold at least type and version */
 215         if (unlikely(!pskb_may_pull(skb, 2)))
 216                 goto err_free;
 217
 218         /* expect a valid ethernet header here. */
 219         if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
 220                 goto err_free;
 221
 222         if (!hard_iface->soft_iface)
 223                 goto err_free;
 224
 225         bat_priv = netdev_priv(hard_iface->soft_iface);
 226
 227         if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
 228                 goto err_free;
 229
 230         /* discard frames on not active interfaces */
 231         if (hard_iface->if_status != IF_ACTIVE)
 232                 goto err_free;
 233
 234         batman_ogm_packet = (struct batman_ogm_packet *)skb->data;
 235
 236         if (batman_ogm_packet->header.version != COMPAT_VERSION) {
 237                 bat_dbg(DBG_BATMAN, bat_priv,
 238                         "Drop packet: incompatible batman version (%i)\n",
 239                         batman_ogm_packet->header.version);
 240                 goto err_free;
 241         }
 242
 243         /* all receive handlers return whether they received or reused
 244          * the supplied skb. if not, we have to free the skb.
 245          */
 246         idx = batman_ogm_packet->header.packet_type;
 247         ret = (*recv_packet_handler[idx])(skb, hard_iface);
 248
 249         if (ret == NET_RX_DROP)
 250                 kfree_skb(skb);
 251
 252         /* return NET_RX_SUCCESS in any case as we
 253          * most probably dropped the packet for
 254          * routing-logical reasons.
 255          */
 256         return NET_RX_SUCCESS;
 257
 258 err_free:
 259         kfree_skb(skb);
 260 err_out:
 261         return NET_RX_DROP;
 262 }
 263
 264 static void recv_handler_init(void)
 265 {
 266         int i;
 267
 268         for (i = 0; i < ARRAY_SIZE(recv_packet_handler); i++)
 269                 recv_packet_handler[i] = recv_unhandled_packet;
 270
 271         /* batman icmp packet */
 272         recv_packet_handler[BAT_ICMP] = recv_icmp_packet;
 273         /* unicast packet */
 274         recv_packet_handler[BAT_UNICAST] = recv_unicast_packet;
 275         /* fragmented unicast packet */
 276         recv_packet_handler[BAT_UNICAST_FRAG] = recv_ucast_frag_packet;
 277         /* broadcast packet */
 278         recv_packet_handler[BAT_BCAST] = recv_bcast_packet;
 279         /* vis packet */
 280         recv_packet_handler[BAT_VIS] = recv_vis_packet;
 281         /* Translation table query (request or response) */
 282         recv_packet_handler[BAT_TT_QUERY] = recv_tt_query;
 283         /* Roaming advertisement */
 284         recv_packet_handler[BAT_ROAM_ADV] = recv_roam_adv;
 285 }
 286
 287 int recv_handler_register(uint8_t packet_type,
 288                           int (*recv_handler)(struct sk_buff *,
 289                                               struct hard_iface *))
 290 {
 291         if (recv_packet_handler[packet_type] != &recv_unhandled_packet)
 292                 return -EBUSY;
 293
 294         recv_packet_handler[packet_type] = recv_handler;
 295         return 0;
 296 }
 297
 298 void recv_handler_unregister(uint8_t packet_type)
 299 {
 300         recv_packet_handler[packet_type] = recv_unhandled_packet;
 301 }
 302
 303 static struct bat_algo_ops *bat_algo_get(char *name)
 304 {
 305         struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
 306         struct hlist_node *node;
 307
 308         hlist_for_each_entry(bat_algo_ops_tmp, node, &bat_algo_list, list) {
 309                 if (strcmp(bat_algo_ops_tmp->name, name) != 0)
 310                         continue;
 311
 312                 bat_algo_ops = bat_algo_ops_tmp;
 313                 break;
 314         }
 315
 316         return bat_algo_ops;
 317 }
 318
 319 int bat_algo_register(struct bat_algo_ops *bat_algo_ops)
 320 {
 321         struct bat_algo_ops *bat_algo_ops_tmp;
 322         int ret = -1;
 323
 324         bat_algo_ops_tmp = bat_algo_get(bat_algo_ops->name);
 325         if (bat_algo_ops_tmp) {
 326                 pr_info("Trying to register already registered routing algorithm: %s\n",
 327                         bat_algo_ops->name);
 328                 goto out;
 329         }
 330
 331         /* all algorithms must implement all ops (for now) */
 332         if (!bat_algo_ops->bat_iface_enable ||
 333             !bat_algo_ops->bat_iface_disable ||
 334             !bat_algo_ops->bat_iface_update_mac ||
 335             !bat_algo_ops->bat_primary_iface_set ||
 336             !bat_algo_ops->bat_ogm_schedule ||
 337             !bat_algo_ops->bat_ogm_emit) {
 338                 pr_info("Routing algo '%s' does not implement required ops\n",
 339                         bat_algo_ops->name);
 340                 goto out;
 341         }
 342
 343         INIT_HLIST_NODE(&bat_algo_ops->list);
 344         hlist_add_head(&bat_algo_ops->list, &bat_algo_list);
 345         ret = 0;
 346
 347 out:
 348         return ret;
 349 }
 350
 351 int bat_algo_select(struct bat_priv *bat_priv, char *name)
 352 {
 353         struct bat_algo_ops *bat_algo_ops;
 354         int ret = -1;
 355
 356         bat_algo_ops = bat_algo_get(name);
 357         if (!bat_algo_ops)
 358                 goto out;
 359
 360         bat_priv->bat_algo_ops = bat_algo_ops;
 361         ret = 0;
 362
 363 out:
 364         return ret;
 365 }
 366
 367 int bat_algo_seq_print_text(struct seq_file *seq, void *offset)
 368 {
 369         struct bat_algo_ops *bat_algo_ops;
 370         struct hlist_node *node;
 371
 372         seq_printf(seq, "Available routing algorithms:\n");
 373
 374         hlist_for_each_entry(bat_algo_ops, node, &bat_algo_list, list) {
 375                 seq_printf(seq, "%s\n", bat_algo_ops->name);
 376         }
 377
 378         return 0;
 379 }
 380
 381 static int param_set_ra(const char *val, const struct kernel_param *kp)
 382 {
 383         struct bat_algo_ops *bat_algo_ops;
 384
 385         bat_algo_ops = bat_algo_get((char *)val);
 386         if (!bat_algo_ops) {
 387                 pr_err("Routing algorithm '%s' is not supported\n", val);
 388                 return -EINVAL;
 389         }
 390
 391         return param_set_copystring(val, kp);
 392 }
 393
 394 static const struct kernel_param_ops param_ops_ra = {
 395         .set = param_set_ra,
 396         .get = param_get_string,
 397 };
 398
 399 static struct kparam_string __param_string_ra = {
 400         .maxlen = sizeof(bat_routing_algo),
 401         .string = bat_routing_algo,
 402 };
 403
 404 module_param_cb(routing_algo, &param_ops_ra, &__param_string_ra, 0644);
 405 module_init(batman_init);
 406 module_exit(batman_exit);
 407
 408 MODULE_LICENSE("GPL");
 409
 410 MODULE_AUTHOR(DRIVER_AUTHOR);
 411 MODULE_DESCRIPTION(DRIVER_DESC);
 412 MODULE_SUPPORTED_DEVICE(DRIVER_DEVICE);
 413 MODULE_VERSION(SOURCE_VERSION);