net/batman-adv/hard-interface.c

   1 /* Copyright (C) 2007-2013 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 "distributed-arp-table.h"
  22 #include "hard-interface.h"
  23 #include "soft-interface.h"
  24 #include "send.h"
  25 #include "translation-table.h"
  26 #include "routing.h"
  27 #include "sysfs.h"
  28 #include "originator.h"
  29 #include "hash.h"
  30 #include "bridge_loop_avoidance.h"
  31
  32 #include <linux/if_arp.h>
  33 #include <linux/if_ether.h>
  34
  35 void batadv_hardif_free_rcu(struct rcu_head *rcu)
  36 {
  37         struct batadv_hard_iface *hard_iface;
  38
  39         hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
  40         dev_put(hard_iface->net_dev);
  41         kfree(hard_iface);
  42 }
  43
  44 struct batadv_hard_iface *
  45 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
  46 {
  47         struct batadv_hard_iface *hard_iface;
  48
  49         rcu_read_lock();
  50         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
  51                 if (hard_iface->net_dev == net_dev &&
  52                     atomic_inc_not_zero(&hard_iface->refcount))
  53                         goto out;
  54         }
  55
  56         hard_iface = NULL;
  57
  58 out:
  59         rcu_read_unlock();
  60         return hard_iface;
  61 }
  62
  63 /**
  64  * batadv_is_on_batman_iface - check if a device is a batman iface descendant
  65  * @net_dev: the device to check
  66  *
  67  * If the user creates any virtual device on top of a batman-adv interface, it
  68  * is important to prevent this new interface to be used to create a new mesh
  69  * network (this behaviour would lead to a batman-over-batman configuration).
  70  * This function recursively checks all the fathers of the device passed as
  71  * argument looking for a batman-adv soft interface.
  72  *
  73  * Returns true if the device is descendant of a batman-adv mesh interface (or
  74  * if it is a batman-adv interface itself), false otherwise
  75  */
  76 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
  77 {
  78         struct net_device *parent_dev;
  79         bool ret;
  80
  81         /* check if this is a batman-adv mesh interface */
  82         if (batadv_softif_is_valid(net_dev))
  83                 return true;
  84
  85         /* no more parents..stop recursion */
  86         if (net_dev->iflink == net_dev->ifindex)
  87                 return false;
  88
  89         /* recurse over the parent device */
  90         parent_dev = dev_get_by_index(&init_net, net_dev->iflink);
  91         /* if we got a NULL parent_dev there is something broken.. */
  92         if (WARN(!parent_dev, "Cannot find parent device"))
  93                 return false;
  94
  95         ret = batadv_is_on_batman_iface(parent_dev);
  96
  97         if (parent_dev)
  98                 dev_put(parent_dev);
  99         return ret;
 100 }
 101
 102 static int batadv_is_valid_iface(const struct net_device *net_dev)
 103 {
 104         if (net_dev->flags & IFF_LOOPBACK)
 105                 return 0;
 106
 107         if (net_dev->type != ARPHRD_ETHER)
 108                 return 0;
 109
 110         if (net_dev->addr_len != ETH_ALEN)
 111                 return 0;
 112
 113         /* no batman over batman */
 114         if (batadv_is_on_batman_iface(net_dev))
 115                 return 0;
 116
 117         return 1;
 118 }
 119
 120 static struct batadv_hard_iface *
 121 batadv_hardif_get_active(const struct net_device *soft_iface)
 122 {
 123         struct batadv_hard_iface *hard_iface;
 124
 125         rcu_read_lock();
 126         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 127                 if (hard_iface->soft_iface != soft_iface)
 128                         continue;
 129
 130                 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
 131                     atomic_inc_not_zero(&hard_iface->refcount))
 132                         goto out;
 133         }
 134
 135         hard_iface = NULL;
 136
 137 out:
 138         rcu_read_unlock();
 139         return hard_iface;
 140 }
 141
 142 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
 143                                           struct batadv_hard_iface *oldif)
 144 {
 145         struct batadv_vis_packet *vis_packet;
 146         struct batadv_hard_iface *primary_if;
 147         struct sk_buff *skb;
 148
 149         primary_if = batadv_primary_if_get_selected(bat_priv);
 150         if (!primary_if)
 151                 goto out;
 152
 153         batadv_dat_init_own_addr(bat_priv, primary_if);
 154
 155         skb = bat_priv->vis.my_info->skb_packet;
 156         vis_packet = (struct batadv_vis_packet *)skb->data;
 157         memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 158         memcpy(vis_packet->sender_orig,
 159                primary_if->net_dev->dev_addr, ETH_ALEN);
 160
 161         batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
 162 out:
 163         if (primary_if)
 164                 batadv_hardif_free_ref(primary_if);
 165 }
 166
 167 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
 168                                      struct batadv_hard_iface *new_hard_iface)
 169 {
 170         struct batadv_hard_iface *curr_hard_iface;
 171
 172         ASSERT_RTNL();
 173
 174         if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
 175                 new_hard_iface = NULL;
 176
 177         curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
 178         rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
 179
 180         if (!new_hard_iface)
 181                 goto out;
 182
 183         bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
 184         batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
 185
 186 out:
 187         if (curr_hard_iface)
 188                 batadv_hardif_free_ref(curr_hard_iface);
 189 }
 190
 191 static bool
 192 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
 193 {
 194         if (hard_iface->net_dev->flags & IFF_UP)
 195                 return true;
 196
 197         return false;
 198 }
 199
 200 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
 201 {
 202         const struct batadv_hard_iface *hard_iface;
 203
 204         rcu_read_lock();
 205         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 206                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 207                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 208                         continue;
 209
 210                 if (hard_iface->net_dev == net_dev)
 211                         continue;
 212
 213                 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
 214                                         net_dev->dev_addr))
 215                         continue;
 216
 217                 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
 218                         net_dev->dev_addr, hard_iface->net_dev->name);
 219                 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
 220         }
 221         rcu_read_unlock();
 222 }
 223
 224 int batadv_hardif_min_mtu(struct net_device *soft_iface)
 225 {
 226         const struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 227         const struct batadv_hard_iface *hard_iface;
 228         /* allow big frames if all devices are capable to do so
 229          * (have MTU > 1500 + BAT_HEADER_LEN)
 230          */
 231         int min_mtu = ETH_DATA_LEN;
 232
 233         if (atomic_read(&bat_priv->fragmentation))
 234                 goto out;
 235
 236         rcu_read_lock();
 237         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 238                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 239                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 240                         continue;
 241
 242                 if (hard_iface->soft_iface != soft_iface)
 243                         continue;
 244
 245                 min_mtu = min_t(int,
 246                                 hard_iface->net_dev->mtu - BATADV_HEADER_LEN,
 247                                 min_mtu);
 248         }
 249         rcu_read_unlock();
 250 out:
 251         return min_mtu;
 252 }
 253
 254 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
 255 void batadv_update_min_mtu(struct net_device *soft_iface)
 256 {
 257         int min_mtu;
 258
 259         min_mtu = batadv_hardif_min_mtu(soft_iface);
 260         if (soft_iface->mtu != min_mtu)
 261                 soft_iface->mtu = min_mtu;
 262 }
 263
 264 static void
 265 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 266 {
 267         struct batadv_priv *bat_priv;
 268         struct batadv_hard_iface *primary_if = NULL;
 269
 270         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 271                 goto out;
 272
 273         bat_priv = netdev_priv(hard_iface->soft_iface);
 274
 275         bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
 276         hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
 277
 278         /* the first active interface becomes our primary interface or
 279          * the next active interface after the old primary interface was removed
 280          */
 281         primary_if = batadv_primary_if_get_selected(bat_priv);
 282         if (!primary_if)
 283                 batadv_primary_if_select(bat_priv, hard_iface);
 284
 285         batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
 286                     hard_iface->net_dev->name);
 287
 288         batadv_update_min_mtu(hard_iface->soft_iface);
 289
 290 out:
 291         if (primary_if)
 292                 batadv_hardif_free_ref(primary_if);
 293 }
 294
 295 static void
 296 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
 297 {
 298         if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 299             (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 300                 return;
 301
 302         hard_iface->if_status = BATADV_IF_INACTIVE;
 303
 304         batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
 305                     hard_iface->net_dev->name);
 306
 307         batadv_update_min_mtu(hard_iface->soft_iface);
 308 }
 309
 310 /**
 311  * batadv_master_del_slave - remove hard_iface from the current master interface
 312  * @slave: the interface enslaved in another master
 313  * @master: the master from which slave has to be removed
 314  *
 315  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
 316  * is free'd and master can correctly change its internal state.
 317  * Return 0 on success, a negative value representing the error otherwise
 318  */
 319 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
 320                                    struct net_device *master)
 321 {
 322         int ret;
 323
 324         if (!master)
 325                 return 0;
 326
 327         ret = -EBUSY;
 328         if (master->netdev_ops->ndo_del_slave)
 329                 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
 330
 331         return ret;
 332 }
 333
 334 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 335                                    const char *iface_name)
 336 {
 337         struct batadv_priv *bat_priv;
 338         struct net_device *soft_iface, *master;
 339         __be16 ethertype = __constant_htons(ETH_P_BATMAN);
 340         int ret;
 341
 342         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 343                 goto out;
 344
 345         if (!atomic_inc_not_zero(&hard_iface->refcount))
 346                 goto out;
 347
 348         soft_iface = dev_get_by_name(&init_net, iface_name);
 349
 350         if (!soft_iface) {
 351                 soft_iface = batadv_softif_create(iface_name);
 352
 353                 if (!soft_iface) {
 354                         ret = -ENOMEM;
 355                         goto err;
 356                 }
 357
 358                 /* dev_get_by_name() increases the reference counter for us */
 359                 dev_hold(soft_iface);
 360         }
 361
 362         if (!batadv_softif_is_valid(soft_iface)) {
 363                 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
 364                        soft_iface->name);
 365                 ret = -EINVAL;
 366                 goto err_dev;
 367         }
 368
 369         /* check if the interface is enslaved in another virtual one and
 370          * in that case unlink it first
 371          */
 372         master = netdev_master_upper_dev_get(hard_iface->net_dev);
 373         ret = batadv_master_del_slave(hard_iface, master);
 374         if (ret)
 375                 goto err_dev;
 376
 377         hard_iface->soft_iface = soft_iface;
 378         bat_priv = netdev_priv(hard_iface->soft_iface);
 379
 380         ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
 381         if (ret)
 382                 goto err_dev;
 383
 384         ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
 385         if (ret < 0)
 386                 goto err_upper;
 387
 388         hard_iface->if_num = bat_priv->num_ifaces;
 389         bat_priv->num_ifaces++;
 390         hard_iface->if_status = BATADV_IF_INACTIVE;
 391         ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
 392         if (ret < 0) {
 393                 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
 394                 bat_priv->num_ifaces--;
 395                 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 396                 goto err_upper;
 397         }
 398
 399         hard_iface->batman_adv_ptype.type = ethertype;
 400         hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
 401         hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
 402         dev_add_pack(&hard_iface->batman_adv_ptype);
 403
 404         atomic_set(&hard_iface->frag_seqno, 1);
 405         batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
 406                     hard_iface->net_dev->name);
 407
 408         if (atomic_read(&bat_priv->fragmentation) &&
 409             hard_iface->net_dev->mtu < ETH_DATA_LEN + BATADV_HEADER_LEN)
 410                 batadv_info(hard_iface->soft_iface,
 411                             "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %zi would solve the problem.\n",
 412                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 413                             ETH_DATA_LEN + BATADV_HEADER_LEN);
 414
 415         if (!atomic_read(&bat_priv->fragmentation) &&
 416             hard_iface->net_dev->mtu < ETH_DATA_LEN + BATADV_HEADER_LEN)
 417                 batadv_info(hard_iface->soft_iface,
 418                             "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %zi.\n",
 419                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 420                             ETH_DATA_LEN + BATADV_HEADER_LEN);
 421
 422         if (batadv_hardif_is_iface_up(hard_iface))
 423                 batadv_hardif_activate_interface(hard_iface);
 424         else
 425                 batadv_err(hard_iface->soft_iface,
 426                            "Not using interface %s (retrying later): interface not active\n",
 427                            hard_iface->net_dev->name);
 428
 429         /* begin scheduling originator messages on that interface */
 430         batadv_schedule_bat_ogm(hard_iface);
 431
 432 out:
 433         return 0;
 434
 435 err_upper:
 436         netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
 437 err_dev:
 438         hard_iface->soft_iface = NULL;
 439         dev_put(soft_iface);
 440 err:
 441         batadv_hardif_free_ref(hard_iface);
 442         return ret;
 443 }
 444
 445 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
 446                                      enum batadv_hard_if_cleanup autodel)
 447 {
 448         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 449         struct batadv_hard_iface *primary_if = NULL;
 450
 451         if (hard_iface->if_status == BATADV_IF_ACTIVE)
 452                 batadv_hardif_deactivate_interface(hard_iface);
 453
 454         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 455                 goto out;
 456
 457         batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
 458                     hard_iface->net_dev->name);
 459         dev_remove_pack(&hard_iface->batman_adv_ptype);
 460
 461         bat_priv->num_ifaces--;
 462         batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
 463
 464         primary_if = batadv_primary_if_get_selected(bat_priv);
 465         if (hard_iface == primary_if) {
 466                 struct batadv_hard_iface *new_if;
 467
 468                 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
 469                 batadv_primary_if_select(bat_priv, new_if);
 470
 471                 if (new_if)
 472                         batadv_hardif_free_ref(new_if);
 473         }
 474
 475         bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
 476         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 477
 478         /* delete all references to this hard_iface */
 479         batadv_purge_orig_ref(bat_priv);
 480         batadv_purge_outstanding_packets(bat_priv, hard_iface);
 481         dev_put(hard_iface->soft_iface);
 482
 483         /* nobody uses this interface anymore */
 484         if (!bat_priv->num_ifaces && autodel == BATADV_IF_CLEANUP_AUTO)
 485                 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
 486
 487         netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
 488         hard_iface->soft_iface = NULL;
 489         batadv_hardif_free_ref(hard_iface);
 490
 491 out:
 492         if (primary_if)
 493                 batadv_hardif_free_ref(primary_if);
 494 }
 495
 496 /**
 497  * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
 498  * @work: work queue item
 499  *
 500  * Free the parts of the hard interface which can not be removed under
 501  * rtnl lock (to prevent deadlock situations).
 502  */
 503 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
 504 {
 505         struct batadv_hard_iface *hard_iface;
 506
 507         hard_iface = container_of(work, struct batadv_hard_iface,
 508                                   cleanup_work);
 509
 510         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 511         batadv_hardif_free_ref(hard_iface);
 512 }
 513
 514 static struct batadv_hard_iface *
 515 batadv_hardif_add_interface(struct net_device *net_dev)
 516 {
 517         struct batadv_hard_iface *hard_iface;
 518         int ret;
 519
 520         ASSERT_RTNL();
 521
 522         ret = batadv_is_valid_iface(net_dev);
 523         if (ret != 1)
 524                 goto out;
 525
 526         dev_hold(net_dev);
 527
 528         hard_iface = kmalloc(sizeof(*hard_iface), GFP_ATOMIC);
 529         if (!hard_iface)
 530                 goto release_dev;
 531
 532         ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
 533         if (ret)
 534                 goto free_if;
 535
 536         hard_iface->if_num = -1;
 537         hard_iface->net_dev = net_dev;
 538         hard_iface->soft_iface = NULL;
 539         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 540         INIT_LIST_HEAD(&hard_iface->list);
 541         INIT_WORK(&hard_iface->cleanup_work,
 542                   batadv_hardif_remove_interface_finish);
 543
 544         /* extra reference for return */
 545         atomic_set(&hard_iface->refcount, 2);
 546
 547         batadv_check_known_mac_addr(hard_iface->net_dev);
 548         list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
 549
 550         /* This can't be called via a bat_priv callback because
 551          * we have no bat_priv yet.
 552          */
 553         atomic_set(&hard_iface->bat_iv.ogm_seqno, 1);
 554         hard_iface->bat_iv.ogm_buff = NULL;
 555
 556         return hard_iface;
 557
 558 free_if:
 559         kfree(hard_iface);
 560 release_dev:
 561         dev_put(net_dev);
 562 out:
 563         return NULL;
 564 }
 565
 566 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
 567 {
 568         ASSERT_RTNL();
 569
 570         /* first deactivate interface */
 571         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 572                 batadv_hardif_disable_interface(hard_iface,
 573                                                 BATADV_IF_CLEANUP_AUTO);
 574
 575         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 576                 return;
 577
 578         hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
 579         queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
 580 }
 581
 582 void batadv_hardif_remove_interfaces(void)
 583 {
 584         struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
 585
 586         rtnl_lock();
 587         list_for_each_entry_safe(hard_iface, hard_iface_tmp,
 588                                  &batadv_hardif_list, list) {
 589                 list_del_rcu(&hard_iface->list);
 590                 batadv_hardif_remove_interface(hard_iface);
 591         }
 592         rtnl_unlock();
 593 }
 594
 595 static int batadv_hard_if_event(struct notifier_block *this,
 596                                 unsigned long event, void *ptr)
 597 {
 598         struct net_device *net_dev = ptr;
 599         struct batadv_hard_iface *hard_iface;
 600         struct batadv_hard_iface *primary_if = NULL;
 601         struct batadv_priv *bat_priv;
 602
 603         if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
 604                 batadv_sysfs_add_meshif(net_dev);
 605                 return NOTIFY_DONE;
 606         }
 607
 608         hard_iface = batadv_hardif_get_by_netdev(net_dev);
 609         if (!hard_iface && event == NETDEV_REGISTER)
 610                 hard_iface = batadv_hardif_add_interface(net_dev);
 611
 612         if (!hard_iface)
 613                 goto out;
 614
 615         switch (event) {
 616         case NETDEV_UP:
 617                 batadv_hardif_activate_interface(hard_iface);
 618                 break;
 619         case NETDEV_GOING_DOWN:
 620         case NETDEV_DOWN:
 621                 batadv_hardif_deactivate_interface(hard_iface);
 622                 break;
 623         case NETDEV_UNREGISTER:
 624                 list_del_rcu(&hard_iface->list);
 625
 626                 batadv_hardif_remove_interface(hard_iface);
 627                 break;
 628         case NETDEV_CHANGEMTU:
 629                 if (hard_iface->soft_iface)
 630                         batadv_update_min_mtu(hard_iface->soft_iface);
 631                 break;
 632         case NETDEV_CHANGEADDR:
 633                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 634                         goto hardif_put;
 635
 636                 batadv_check_known_mac_addr(hard_iface->net_dev);
 637
 638                 bat_priv = netdev_priv(hard_iface->soft_iface);
 639                 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
 640
 641                 primary_if = batadv_primary_if_get_selected(bat_priv);
 642                 if (!primary_if)
 643                         goto hardif_put;
 644
 645                 if (hard_iface == primary_if)
 646                         batadv_primary_if_update_addr(bat_priv, NULL);
 647                 break;
 648         default:
 649                 break;
 650         }
 651
 652 hardif_put:
 653         batadv_hardif_free_ref(hard_iface);
 654 out:
 655         if (primary_if)
 656                 batadv_hardif_free_ref(primary_if);
 657         return NOTIFY_DONE;
 658 }
 659
 660 /* This function returns true if the interface represented by ifindex is a
 661  * 802.11 wireless device
 662  */
 663 bool batadv_is_wifi_iface(int ifindex)
 664 {
 665         struct net_device *net_device = NULL;
 666         bool ret = false;
 667
 668         if (ifindex == BATADV_NULL_IFINDEX)
 669                 goto out;
 670
 671         net_device = dev_get_by_index(&init_net, ifindex);
 672         if (!net_device)
 673                 goto out;
 674
 675 #ifdef CONFIG_WIRELESS_EXT
 676         /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
 677          * check for wireless_handlers != NULL
 678          */
 679         if (net_device->wireless_handlers)
 680                 ret = true;
 681         else
 682 #endif
 683                 /* cfg80211 drivers have to set ieee80211_ptr */
 684                 if (net_device->ieee80211_ptr)
 685                         ret = true;
 686 out:
 687         if (net_device)
 688                 dev_put(net_device);
 689         return ret;
 690 }
 691
 692 struct notifier_block batadv_hard_if_notifier = {
 693         .notifier_call = batadv_hard_if_event,
 694 };