net/batman-adv/hard-interface.c

   1 /* Copyright (C) 2007-2016  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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "hard-interface.h"
  19 #include "main.h"
  20
  21 #include <linux/atomic.h>
  22 #include <linux/byteorder/generic.h>
  23 #include <linux/errno.h>
  24 #include <linux/fs.h>
  25 #include <linux/if.h>
  26 #include <linux/if_arp.h>
  27 #include <linux/if_ether.h>
  28 #include <linux/kernel.h>
  29 #include <linux/kref.h>
  30 #include <linux/list.h>
  31 #include <linux/mutex.h>
  32 #include <linux/netdevice.h>
  33 #include <linux/printk.h>
  34 #include <linux/rculist.h>
  35 #include <linux/rtnetlink.h>
  36 #include <linux/slab.h>
  37 #include <linux/spinlock.h>
  38 #include <net/net_namespace.h>
  39 #include <net/rtnetlink.h>
  40
  41 #include "bat_v.h"
  42 #include "bridge_loop_avoidance.h"
  43 #include "debugfs.h"
  44 #include "distributed-arp-table.h"
  45 #include "gateway_client.h"
  46 #include "log.h"
  47 #include "originator.h"
  48 #include "packet.h"
  49 #include "send.h"
  50 #include "soft-interface.h"
  51 #include "sysfs.h"
  52 #include "translation-table.h"
  53
  54 /**
  55  * batadv_hardif_release - release hard interface from lists and queue for
  56  *  free after rcu grace period
  57  * @ref: kref pointer of the hard interface
  58  */
  59 void batadv_hardif_release(struct kref *ref)
  60 {
  61         struct batadv_hard_iface *hard_iface;
  62
  63         hard_iface = container_of(ref, struct batadv_hard_iface, refcount);
  64         dev_put(hard_iface->net_dev);
  65
  66         kfree_rcu(hard_iface, rcu);
  67 }
  68
  69 struct batadv_hard_iface *
  70 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
  71 {
  72         struct batadv_hard_iface *hard_iface;
  73
  74         rcu_read_lock();
  75         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
  76                 if (hard_iface->net_dev == net_dev &&
  77                     kref_get_unless_zero(&hard_iface->refcount))
  78                         goto out;
  79         }
  80
  81         hard_iface = NULL;
  82
  83 out:
  84         rcu_read_unlock();
  85         return hard_iface;
  86 }
  87
  88 /**
  89  * batadv_getlink_net - return link net namespace (of use fallback)
  90  * @netdev: net_device to check
  91  * @fallback_net: return in case get_link_net is not available for @netdev
  92  *
  93  * Return: result of rtnl_link_ops->get_link_net or @fallback_net
  94  */
  95 static const struct net *batadv_getlink_net(const struct net_device *netdev,
  96                                             const struct net *fallback_net)
  97 {
  98         if (!netdev->rtnl_link_ops)
  99                 return fallback_net;
 100
 101         if (!netdev->rtnl_link_ops->get_link_net)
 102                 return fallback_net;
 103
 104         return netdev->rtnl_link_ops->get_link_net(netdev);
 105 }
 106
 107 /**
 108  * batadv_mutual_parents - check if two devices are each others parent
 109  * @dev1: 1st net dev
 110  * @net1: 1st devices netns
 111  * @dev2: 2nd net dev
 112  * @net2: 2nd devices netns
 113  *
 114  * veth devices come in pairs and each is the parent of the other!
 115  *
 116  * Return: true if the devices are each others parent, otherwise false
 117  */
 118 static bool batadv_mutual_parents(const struct net_device *dev1,
 119                                   const struct net *net1,
 120                                   const struct net_device *dev2,
 121                                   const struct net *net2)
 122 {
 123         int dev1_parent_iflink = dev_get_iflink(dev1);
 124         int dev2_parent_iflink = dev_get_iflink(dev2);
 125         const struct net *dev1_parent_net;
 126         const struct net *dev2_parent_net;
 127
 128         dev1_parent_net = batadv_getlink_net(dev1, net1);
 129         dev2_parent_net = batadv_getlink_net(dev2, net2);
 130
 131         if (!dev1_parent_iflink || !dev2_parent_iflink)
 132                 return false;
 133
 134         return (dev1_parent_iflink == dev2->ifindex) &&
 135                (dev2_parent_iflink == dev1->ifindex) &&
 136                net_eq(dev1_parent_net, net2) &&
 137                net_eq(dev2_parent_net, net1);
 138 }
 139
 140 /**
 141  * batadv_is_on_batman_iface - check if a device is a batman iface descendant
 142  * @net_dev: the device to check
 143  *
 144  * If the user creates any virtual device on top of a batman-adv interface, it
 145  * is important to prevent this new interface to be used to create a new mesh
 146  * network (this behaviour would lead to a batman-over-batman configuration).
 147  * This function recursively checks all the fathers of the device passed as
 148  * argument looking for a batman-adv soft interface.
 149  *
 150  * Return: true if the device is descendant of a batman-adv mesh interface (or
 151  * if it is a batman-adv interface itself), false otherwise
 152  */
 153 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
 154 {
 155         struct net *net = dev_net(net_dev);
 156         struct net_device *parent_dev;
 157         const struct net *parent_net;
 158         bool ret;
 159
 160         /* check if this is a batman-adv mesh interface */
 161         if (batadv_softif_is_valid(net_dev))
 162                 return true;
 163
 164         /* no more parents..stop recursion */
 165         if (dev_get_iflink(net_dev) == 0 ||
 166             dev_get_iflink(net_dev) == net_dev->ifindex)
 167                 return false;
 168
 169         parent_net = batadv_getlink_net(net_dev, net);
 170
 171         /* recurse over the parent device */
 172         parent_dev = __dev_get_by_index((struct net *)parent_net,
 173                                         dev_get_iflink(net_dev));
 174         /* if we got a NULL parent_dev there is something broken.. */
 175         if (!parent_dev) {
 176                 pr_err("Cannot find parent device\n");
 177                 return false;
 178         }
 179
 180         if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net))
 181                 return false;
 182
 183         ret = batadv_is_on_batman_iface(parent_dev);
 184
 185         return ret;
 186 }
 187
 188 static bool batadv_is_valid_iface(const struct net_device *net_dev)
 189 {
 190         if (net_dev->flags & IFF_LOOPBACK)
 191                 return false;
 192
 193         if (net_dev->type != ARPHRD_ETHER)
 194                 return false;
 195
 196         if (net_dev->addr_len != ETH_ALEN)
 197                 return false;
 198
 199         /* no batman over batman */
 200         if (batadv_is_on_batman_iface(net_dev))
 201                 return false;
 202
 203         return true;
 204 }
 205
 206 /**
 207  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
 208  *  interface
 209  * @net_device: the device to check
 210  *
 211  * Return: true if the net device is a 802.11 wireless device, false otherwise.
 212  */
 213 bool batadv_is_wifi_netdev(struct net_device *net_device)
 214 {
 215         if (!net_device)
 216                 return false;
 217
 218 #ifdef CONFIG_WIRELESS_EXT
 219         /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
 220          * check for wireless_handlers != NULL
 221          */
 222         if (net_device->wireless_handlers)
 223                 return true;
 224 #endif
 225
 226         /* cfg80211 drivers have to set ieee80211_ptr */
 227         if (net_device->ieee80211_ptr)
 228                 return true;
 229
 230         return false;
 231 }
 232
 233 static struct batadv_hard_iface *
 234 batadv_hardif_get_active(const struct net_device *soft_iface)
 235 {
 236         struct batadv_hard_iface *hard_iface;
 237
 238         rcu_read_lock();
 239         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 240                 if (hard_iface->soft_iface != soft_iface)
 241                         continue;
 242
 243                 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
 244                     kref_get_unless_zero(&hard_iface->refcount))
 245                         goto out;
 246         }
 247
 248         hard_iface = NULL;
 249
 250 out:
 251         rcu_read_unlock();
 252         return hard_iface;
 253 }
 254
 255 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
 256                                           struct batadv_hard_iface *oldif)
 257 {
 258         struct batadv_hard_iface *primary_if;
 259
 260         primary_if = batadv_primary_if_get_selected(bat_priv);
 261         if (!primary_if)
 262                 goto out;
 263
 264         batadv_dat_init_own_addr(bat_priv, primary_if);
 265         batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
 266 out:
 267         if (primary_if)
 268                 batadv_hardif_put(primary_if);
 269 }
 270
 271 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
 272                                      struct batadv_hard_iface *new_hard_iface)
 273 {
 274         struct batadv_hard_iface *curr_hard_iface;
 275
 276         ASSERT_RTNL();
 277
 278         if (new_hard_iface)
 279                 kref_get(&new_hard_iface->refcount);
 280
 281         curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
 282         rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
 283
 284         if (!new_hard_iface)
 285                 goto out;
 286
 287         bat_priv->algo_ops->iface.primary_set(new_hard_iface);
 288         batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
 289
 290 out:
 291         if (curr_hard_iface)
 292                 batadv_hardif_put(curr_hard_iface);
 293 }
 294
 295 static bool
 296 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
 297 {
 298         if (hard_iface->net_dev->flags & IFF_UP)
 299                 return true;
 300
 301         return false;
 302 }
 303
 304 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
 305 {
 306         const struct batadv_hard_iface *hard_iface;
 307
 308         rcu_read_lock();
 309         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 310                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 311                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 312                         continue;
 313
 314                 if (hard_iface->net_dev == net_dev)
 315                         continue;
 316
 317                 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
 318                                         net_dev->dev_addr))
 319                         continue;
 320
 321                 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
 322                         net_dev->dev_addr, hard_iface->net_dev->name);
 323                 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
 324         }
 325         rcu_read_unlock();
 326 }
 327
 328 /**
 329  * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
 330  * @soft_iface: netdev struct of the mesh interface
 331  */
 332 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
 333 {
 334         const struct batadv_hard_iface *hard_iface;
 335         unsigned short lower_header_len = ETH_HLEN;
 336         unsigned short lower_headroom = 0;
 337         unsigned short lower_tailroom = 0;
 338         unsigned short needed_headroom;
 339
 340         rcu_read_lock();
 341         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 342                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 343                         continue;
 344
 345                 if (hard_iface->soft_iface != soft_iface)
 346                         continue;
 347
 348                 lower_header_len = max_t(unsigned short, lower_header_len,
 349                                          hard_iface->net_dev->hard_header_len);
 350
 351                 lower_headroom = max_t(unsigned short, lower_headroom,
 352                                        hard_iface->net_dev->needed_headroom);
 353
 354                 lower_tailroom = max_t(unsigned short, lower_tailroom,
 355                                        hard_iface->net_dev->needed_tailroom);
 356         }
 357         rcu_read_unlock();
 358
 359         needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
 360         needed_headroom += batadv_max_header_len();
 361
 362         soft_iface->needed_headroom = needed_headroom;
 363         soft_iface->needed_tailroom = lower_tailroom;
 364 }
 365
 366 int batadv_hardif_min_mtu(struct net_device *soft_iface)
 367 {
 368         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 369         const struct batadv_hard_iface *hard_iface;
 370         int min_mtu = INT_MAX;
 371
 372         rcu_read_lock();
 373         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 374                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 375                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 376                         continue;
 377
 378                 if (hard_iface->soft_iface != soft_iface)
 379                         continue;
 380
 381                 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
 382         }
 383         rcu_read_unlock();
 384
 385         if (atomic_read(&bat_priv->fragmentation) == 0)
 386                 goto out;
 387
 388         /* with fragmentation enabled the maximum size of internally generated
 389          * packets such as translation table exchanges or tvlv containers, etc
 390          * has to be calculated
 391          */
 392         min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
 393         min_mtu -= sizeof(struct batadv_frag_packet);
 394         min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
 395
 396 out:
 397         /* report to the other components the maximum amount of bytes that
 398          * batman-adv can send over the wire (without considering the payload
 399          * overhead). For example, this value is used by TT to compute the
 400          * maximum local table table size
 401          */
 402         atomic_set(&bat_priv->packet_size_max, min_mtu);
 403
 404         /* the real soft-interface MTU is computed by removing the payload
 405          * overhead from the maximum amount of bytes that was just computed.
 406          *
 407          * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
 408          */
 409         return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
 410 }
 411
 412 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
 413 void batadv_update_min_mtu(struct net_device *soft_iface)
 414 {
 415         soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
 416
 417         /* Check if the local translate table should be cleaned up to match a
 418          * new (and smaller) MTU.
 419          */
 420         batadv_tt_local_resize_to_mtu(soft_iface);
 421 }
 422
 423 static void
 424 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 425 {
 426         struct batadv_priv *bat_priv;
 427         struct batadv_hard_iface *primary_if = NULL;
 428
 429         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 430                 goto out;
 431
 432         bat_priv = netdev_priv(hard_iface->soft_iface);
 433
 434         bat_priv->algo_ops->iface.update_mac(hard_iface);
 435         hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
 436
 437         /* the first active interface becomes our primary interface or
 438          * the next active interface after the old primary interface was removed
 439          */
 440         primary_if = batadv_primary_if_get_selected(bat_priv);
 441         if (!primary_if)
 442                 batadv_primary_if_select(bat_priv, hard_iface);
 443
 444         batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
 445                     hard_iface->net_dev->name);
 446
 447         batadv_update_min_mtu(hard_iface->soft_iface);
 448
 449         if (bat_priv->algo_ops->iface.activate)
 450                 bat_priv->algo_ops->iface.activate(hard_iface);
 451
 452 out:
 453         if (primary_if)
 454                 batadv_hardif_put(primary_if);
 455 }
 456
 457 static void
 458 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
 459 {
 460         if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 461             (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 462                 return;
 463
 464         hard_iface->if_status = BATADV_IF_INACTIVE;
 465
 466         batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
 467                     hard_iface->net_dev->name);
 468
 469         batadv_update_min_mtu(hard_iface->soft_iface);
 470 }
 471
 472 /**
 473  * batadv_master_del_slave - remove hard_iface from the current master interface
 474  * @slave: the interface enslaved in another master
 475  * @master: the master from which slave has to be removed
 476  *
 477  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
 478  * is free'd and master can correctly change its internal state.
 479  *
 480  * Return: 0 on success, a negative value representing the error otherwise
 481  */
 482 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
 483                                    struct net_device *master)
 484 {
 485         int ret;
 486
 487         if (!master)
 488                 return 0;
 489
 490         ret = -EBUSY;
 491         if (master->netdev_ops->ndo_del_slave)
 492                 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
 493
 494         return ret;
 495 }
 496
 497 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 498                                    struct net *net, const char *iface_name)
 499 {
 500         struct batadv_priv *bat_priv;
 501         struct net_device *soft_iface, *master;
 502         __be16 ethertype = htons(ETH_P_BATMAN);
 503         int max_header_len = batadv_max_header_len();
 504         int ret;
 505
 506         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 507                 goto out;
 508
 509         kref_get(&hard_iface->refcount);
 510
 511         soft_iface = dev_get_by_name(net, iface_name);
 512
 513         if (!soft_iface) {
 514                 soft_iface = batadv_softif_create(net, iface_name);
 515
 516                 if (!soft_iface) {
 517                         ret = -ENOMEM;
 518                         goto err;
 519                 }
 520
 521                 /* dev_get_by_name() increases the reference counter for us */
 522                 dev_hold(soft_iface);
 523         }
 524
 525         if (!batadv_softif_is_valid(soft_iface)) {
 526                 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
 527                        soft_iface->name);
 528                 ret = -EINVAL;
 529                 goto err_dev;
 530         }
 531
 532         /* check if the interface is enslaved in another virtual one and
 533          * in that case unlink it first
 534          */
 535         master = netdev_master_upper_dev_get(hard_iface->net_dev);
 536         ret = batadv_master_del_slave(hard_iface, master);
 537         if (ret)
 538                 goto err_dev;
 539
 540         hard_iface->soft_iface = soft_iface;
 541         bat_priv = netdev_priv(hard_iface->soft_iface);
 542
 543         if (bat_priv->num_ifaces >= UINT_MAX) {
 544                 ret = -ENOSPC;
 545                 goto err_dev;
 546         }
 547
 548         ret = netdev_master_upper_dev_link(hard_iface->net_dev,
 549                                            soft_iface, NULL, NULL);
 550         if (ret)
 551                 goto err_dev;
 552
 553         ret = bat_priv->algo_ops->iface.enable(hard_iface);
 554         if (ret < 0)
 555                 goto err_upper;
 556
 557         hard_iface->if_num = bat_priv->num_ifaces;
 558         bat_priv->num_ifaces++;
 559         hard_iface->if_status = BATADV_IF_INACTIVE;
 560         ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
 561         if (ret < 0) {
 562                 bat_priv->algo_ops->iface.disable(hard_iface);
 563                 bat_priv->num_ifaces--;
 564                 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 565                 goto err_upper;
 566         }
 567
 568         kref_get(&hard_iface->refcount);
 569         hard_iface->batman_adv_ptype.type = ethertype;
 570         hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
 571         hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
 572         dev_add_pack(&hard_iface->batman_adv_ptype);
 573
 574         batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
 575                     hard_iface->net_dev->name);
 576
 577         if (atomic_read(&bat_priv->fragmentation) &&
 578             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 579                 batadv_info(hard_iface->soft_iface,
 580                             "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 %i would solve the problem.\n",
 581                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 582                             ETH_DATA_LEN + max_header_len);
 583
 584         if (!atomic_read(&bat_priv->fragmentation) &&
 585             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 586                 batadv_info(hard_iface->soft_iface,
 587                             "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 %i.\n",
 588                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 589                             ETH_DATA_LEN + max_header_len);
 590
 591         if (batadv_hardif_is_iface_up(hard_iface))
 592                 batadv_hardif_activate_interface(hard_iface);
 593         else
 594                 batadv_err(hard_iface->soft_iface,
 595                            "Not using interface %s (retrying later): interface not active\n",
 596                            hard_iface->net_dev->name);
 597
 598         batadv_hardif_recalc_extra_skbroom(soft_iface);
 599
 600         if (bat_priv->algo_ops->iface.enabled)
 601                 bat_priv->algo_ops->iface.enabled(hard_iface);
 602
 603 out:
 604         return 0;
 605
 606 err_upper:
 607         netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
 608 err_dev:
 609         hard_iface->soft_iface = NULL;
 610         dev_put(soft_iface);
 611 err:
 612         batadv_hardif_put(hard_iface);
 613         return ret;
 614 }
 615
 616 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
 617                                      enum batadv_hard_if_cleanup autodel)
 618 {
 619         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 620         struct batadv_hard_iface *primary_if = NULL;
 621
 622         batadv_hardif_deactivate_interface(hard_iface);
 623
 624         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 625                 goto out;
 626
 627         batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
 628                     hard_iface->net_dev->name);
 629         dev_remove_pack(&hard_iface->batman_adv_ptype);
 630         batadv_hardif_put(hard_iface);
 631
 632         bat_priv->num_ifaces--;
 633         batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
 634
 635         primary_if = batadv_primary_if_get_selected(bat_priv);
 636         if (hard_iface == primary_if) {
 637                 struct batadv_hard_iface *new_if;
 638
 639                 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
 640                 batadv_primary_if_select(bat_priv, new_if);
 641
 642                 if (new_if)
 643                         batadv_hardif_put(new_if);
 644         }
 645
 646         bat_priv->algo_ops->iface.disable(hard_iface);
 647         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 648
 649         /* delete all references to this hard_iface */
 650         batadv_purge_orig_ref(bat_priv);
 651         batadv_purge_outstanding_packets(bat_priv, hard_iface);
 652         dev_put(hard_iface->soft_iface);
 653
 654         netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
 655         batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
 656
 657         /* nobody uses this interface anymore */
 658         if (bat_priv->num_ifaces == 0) {
 659                 batadv_gw_check_client_stop(bat_priv);
 660
 661                 if (autodel == BATADV_IF_CLEANUP_AUTO)
 662                         batadv_softif_destroy_sysfs(hard_iface->soft_iface);
 663         }
 664
 665         hard_iface->soft_iface = NULL;
 666         batadv_hardif_put(hard_iface);
 667
 668 out:
 669         if (primary_if)
 670                 batadv_hardif_put(primary_if);
 671 }
 672
 673 static struct batadv_hard_iface *
 674 batadv_hardif_add_interface(struct net_device *net_dev)
 675 {
 676         struct batadv_hard_iface *hard_iface;
 677         int ret;
 678
 679         ASSERT_RTNL();
 680
 681         if (!batadv_is_valid_iface(net_dev))
 682                 goto out;
 683
 684         dev_hold(net_dev);
 685
 686         hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
 687         if (!hard_iface)
 688                 goto release_dev;
 689
 690         ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
 691         if (ret)
 692                 goto free_if;
 693
 694         hard_iface->if_num = 0;
 695         hard_iface->net_dev = net_dev;
 696         hard_iface->soft_iface = NULL;
 697         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 698
 699         ret = batadv_debugfs_add_hardif(hard_iface);
 700         if (ret)
 701                 goto free_sysfs;
 702
 703         INIT_LIST_HEAD(&hard_iface->list);
 704         INIT_HLIST_HEAD(&hard_iface->neigh_list);
 705
 706         mutex_init(&hard_iface->bat_iv.ogm_buff_mutex);
 707         spin_lock_init(&hard_iface->neigh_list_lock);
 708         kref_init(&hard_iface->refcount);
 709
 710         hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
 711         if (batadv_is_wifi_netdev(net_dev))
 712                 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
 713
 714         batadv_v_hardif_init(hard_iface);
 715
 716         batadv_check_known_mac_addr(hard_iface->net_dev);
 717         kref_get(&hard_iface->refcount);
 718         list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
 719
 720         return hard_iface;
 721
 722 free_sysfs:
 723         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 724 free_if:
 725         kfree(hard_iface);
 726 release_dev:
 727         dev_put(net_dev);
 728 out:
 729         return NULL;
 730 }
 731
 732 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
 733 {
 734         ASSERT_RTNL();
 735
 736         /* first deactivate interface */
 737         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 738                 batadv_hardif_disable_interface(hard_iface,
 739                                                 BATADV_IF_CLEANUP_KEEP);
 740
 741         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 742                 return;
 743
 744         hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
 745         batadv_debugfs_del_hardif(hard_iface);
 746         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 747         batadv_hardif_put(hard_iface);
 748 }
 749
 750 void batadv_hardif_remove_interfaces(void)
 751 {
 752         struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
 753
 754         rtnl_lock();
 755         list_for_each_entry_safe(hard_iface, hard_iface_tmp,
 756                                  &batadv_hardif_list, list) {
 757                 list_del_rcu(&hard_iface->list);
 758                 batadv_hardif_remove_interface(hard_iface);
 759         }
 760         rtnl_unlock();
 761 }
 762
 763 /**
 764  * batadv_hard_if_event_softif() - Handle events for soft interfaces
 765  * @event: NETDEV_* event to handle
 766  * @net_dev: net_device which generated an event
 767  *
 768  * Return: NOTIFY_* result
 769  */
 770 static int batadv_hard_if_event_softif(unsigned long event,
 771                                        struct net_device *net_dev)
 772 {
 773         struct batadv_priv *bat_priv;
 774
 775         switch (event) {
 776         case NETDEV_REGISTER:
 777                 batadv_sysfs_add_meshif(net_dev);
 778                 bat_priv = netdev_priv(net_dev);
 779                 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
 780                 break;
 781         case NETDEV_CHANGENAME:
 782                 batadv_debugfs_rename_meshif(net_dev);
 783                 break;
 784         }
 785
 786         return NOTIFY_DONE;
 787 }
 788
 789 static int batadv_hard_if_event(struct notifier_block *this,
 790                                 unsigned long event, void *ptr)
 791 {
 792         struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
 793         struct batadv_hard_iface *hard_iface;
 794         struct batadv_hard_iface *primary_if = NULL;
 795         struct batadv_priv *bat_priv;
 796
 797         if (batadv_softif_is_valid(net_dev))
 798                 return batadv_hard_if_event_softif(event, net_dev);
 799
 800         hard_iface = batadv_hardif_get_by_netdev(net_dev);
 801         if (!hard_iface && (event == NETDEV_REGISTER ||
 802                             event == NETDEV_POST_TYPE_CHANGE))
 803                 hard_iface = batadv_hardif_add_interface(net_dev);
 804
 805         if (!hard_iface)
 806                 goto out;
 807
 808         switch (event) {
 809         case NETDEV_UP:
 810                 batadv_hardif_activate_interface(hard_iface);
 811                 break;
 812         case NETDEV_GOING_DOWN:
 813         case NETDEV_DOWN:
 814                 batadv_hardif_deactivate_interface(hard_iface);
 815                 break;
 816         case NETDEV_UNREGISTER:
 817         case NETDEV_PRE_TYPE_CHANGE:
 818                 list_del_rcu(&hard_iface->list);
 819
 820                 batadv_hardif_remove_interface(hard_iface);
 821                 break;
 822         case NETDEV_CHANGEMTU:
 823                 if (hard_iface->soft_iface)
 824                         batadv_update_min_mtu(hard_iface->soft_iface);
 825                 break;
 826         case NETDEV_CHANGEADDR:
 827                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 828                         goto hardif_put;
 829
 830                 batadv_check_known_mac_addr(hard_iface->net_dev);
 831
 832                 bat_priv = netdev_priv(hard_iface->soft_iface);
 833                 bat_priv->algo_ops->iface.update_mac(hard_iface);
 834
 835                 primary_if = batadv_primary_if_get_selected(bat_priv);
 836                 if (!primary_if)
 837                         goto hardif_put;
 838
 839                 if (hard_iface == primary_if)
 840                         batadv_primary_if_update_addr(bat_priv, NULL);
 841                 break;
 842         case NETDEV_CHANGENAME:
 843                 batadv_debugfs_rename_hardif(hard_iface);
 844                 break;
 845         default:
 846                 break;
 847         }
 848
 849 hardif_put:
 850         batadv_hardif_put(hard_iface);
 851 out:
 852         if (primary_if)
 853                 batadv_hardif_put(primary_if);
 854         return NOTIFY_DONE;
 855 }
 856
 857 struct notifier_block batadv_hard_if_notifier = {
 858         .notifier_call = batadv_hard_if_event,
 859 };