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         int iflink;
 159         bool ret;
 160
 161         /* check if this is a batman-adv mesh interface */
 162         if (batadv_softif_is_valid(net_dev))
 163                 return true;
 164
 165         iflink = dev_get_iflink(net_dev);
 166         if (iflink == 0)
 167                 return false;
 168
 169         parent_net = batadv_getlink_net(net_dev, net);
 170
 171         /* iflink to itself, most likely physical device */
 172         if (net == parent_net && iflink == net_dev->ifindex)
 173                 return false;
 174
 175         /* recurse over the parent device */
 176         parent_dev = __dev_get_by_index((struct net *)parent_net, iflink);
 177         /* if we got a NULL parent_dev there is something broken.. */
 178         if (!parent_dev) {
 179                 pr_err("Cannot find parent device\n");
 180                 return false;
 181         }
 182
 183         if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net))
 184                 return false;
 185
 186         ret = batadv_is_on_batman_iface(parent_dev);
 187
 188         return ret;
 189 }
 190
 191 static bool batadv_is_valid_iface(const struct net_device *net_dev)
 192 {
 193         if (net_dev->flags & IFF_LOOPBACK)
 194                 return false;
 195
 196         if (net_dev->type != ARPHRD_ETHER)
 197                 return false;
 198
 199         if (net_dev->addr_len != ETH_ALEN)
 200                 return false;
 201
 202         /* no batman over batman */
 203         if (batadv_is_on_batman_iface(net_dev))
 204                 return false;
 205
 206         return true;
 207 }
 208
 209 /**
 210  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
 211  *  interface
 212  * @net_device: the device to check
 213  *
 214  * Return: true if the net device is a 802.11 wireless device, false otherwise.
 215  */
 216 bool batadv_is_wifi_netdev(struct net_device *net_device)
 217 {
 218         if (!net_device)
 219                 return false;
 220
 221 #ifdef CONFIG_WIRELESS_EXT
 222         /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
 223          * check for wireless_handlers != NULL
 224          */
 225         if (net_device->wireless_handlers)
 226                 return true;
 227 #endif
 228
 229         /* cfg80211 drivers have to set ieee80211_ptr */
 230         if (net_device->ieee80211_ptr)
 231                 return true;
 232
 233         return false;
 234 }
 235
 236 static struct batadv_hard_iface *
 237 batadv_hardif_get_active(const struct net_device *soft_iface)
 238 {
 239         struct batadv_hard_iface *hard_iface;
 240
 241         rcu_read_lock();
 242         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 243                 if (hard_iface->soft_iface != soft_iface)
 244                         continue;
 245
 246                 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
 247                     kref_get_unless_zero(&hard_iface->refcount))
 248                         goto out;
 249         }
 250
 251         hard_iface = NULL;
 252
 253 out:
 254         rcu_read_unlock();
 255         return hard_iface;
 256 }
 257
 258 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
 259                                           struct batadv_hard_iface *oldif)
 260 {
 261         struct batadv_hard_iface *primary_if;
 262
 263         primary_if = batadv_primary_if_get_selected(bat_priv);
 264         if (!primary_if)
 265                 goto out;
 266
 267         batadv_dat_init_own_addr(bat_priv, primary_if);
 268         batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
 269 out:
 270         if (primary_if)
 271                 batadv_hardif_put(primary_if);
 272 }
 273
 274 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
 275                                      struct batadv_hard_iface *new_hard_iface)
 276 {
 277         struct batadv_hard_iface *curr_hard_iface;
 278
 279         ASSERT_RTNL();
 280
 281         if (new_hard_iface)
 282                 kref_get(&new_hard_iface->refcount);
 283
 284         curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
 285         rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
 286
 287         if (!new_hard_iface)
 288                 goto out;
 289
 290         bat_priv->algo_ops->iface.primary_set(new_hard_iface);
 291         batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
 292
 293 out:
 294         if (curr_hard_iface)
 295                 batadv_hardif_put(curr_hard_iface);
 296 }
 297
 298 static bool
 299 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
 300 {
 301         if (hard_iface->net_dev->flags & IFF_UP)
 302                 return true;
 303
 304         return false;
 305 }
 306
 307 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
 308 {
 309         const struct batadv_hard_iface *hard_iface;
 310
 311         rcu_read_lock();
 312         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 313                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 314                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 315                         continue;
 316
 317                 if (hard_iface->net_dev == net_dev)
 318                         continue;
 319
 320                 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
 321                                         net_dev->dev_addr))
 322                         continue;
 323
 324                 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
 325                         net_dev->dev_addr, hard_iface->net_dev->name);
 326                 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
 327         }
 328         rcu_read_unlock();
 329 }
 330
 331 /**
 332  * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
 333  * @soft_iface: netdev struct of the mesh interface
 334  */
 335 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
 336 {
 337         const struct batadv_hard_iface *hard_iface;
 338         unsigned short lower_header_len = ETH_HLEN;
 339         unsigned short lower_headroom = 0;
 340         unsigned short lower_tailroom = 0;
 341         unsigned short needed_headroom;
 342
 343         rcu_read_lock();
 344         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 345                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 346                         continue;
 347
 348                 if (hard_iface->soft_iface != soft_iface)
 349                         continue;
 350
 351                 lower_header_len = max_t(unsigned short, lower_header_len,
 352                                          hard_iface->net_dev->hard_header_len);
 353
 354                 lower_headroom = max_t(unsigned short, lower_headroom,
 355                                        hard_iface->net_dev->needed_headroom);
 356
 357                 lower_tailroom = max_t(unsigned short, lower_tailroom,
 358                                        hard_iface->net_dev->needed_tailroom);
 359         }
 360         rcu_read_unlock();
 361
 362         needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
 363         needed_headroom += batadv_max_header_len();
 364
 365         /* fragmentation headers don't strip the unicast/... header */
 366         needed_headroom += sizeof(struct batadv_frag_packet);
 367
 368         soft_iface->needed_headroom = needed_headroom;
 369         soft_iface->needed_tailroom = lower_tailroom;
 370 }
 371
 372 int batadv_hardif_min_mtu(struct net_device *soft_iface)
 373 {
 374         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 375         const struct batadv_hard_iface *hard_iface;
 376         int min_mtu = INT_MAX;
 377
 378         rcu_read_lock();
 379         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 380                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 381                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 382                         continue;
 383
 384                 if (hard_iface->soft_iface != soft_iface)
 385                         continue;
 386
 387                 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
 388         }
 389         rcu_read_unlock();
 390
 391         if (atomic_read(&bat_priv->fragmentation) == 0)
 392                 goto out;
 393
 394         /* with fragmentation enabled the maximum size of internally generated
 395          * packets such as translation table exchanges or tvlv containers, etc
 396          * has to be calculated
 397          */
 398         min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
 399         min_mtu -= sizeof(struct batadv_frag_packet);
 400         min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
 401
 402 out:
 403         /* report to the other components the maximum amount of bytes that
 404          * batman-adv can send over the wire (without considering the payload
 405          * overhead). For example, this value is used by TT to compute the
 406          * maximum local table table size
 407          */
 408         atomic_set(&bat_priv->packet_size_max, min_mtu);
 409
 410         /* the real soft-interface MTU is computed by removing the payload
 411          * overhead from the maximum amount of bytes that was just computed.
 412          *
 413          * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
 414          */
 415         return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
 416 }
 417
 418 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
 419 void batadv_update_min_mtu(struct net_device *soft_iface)
 420 {
 421         soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
 422
 423         /* Check if the local translate table should be cleaned up to match a
 424          * new (and smaller) MTU.
 425          */
 426         batadv_tt_local_resize_to_mtu(soft_iface);
 427 }
 428
 429 static void
 430 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 431 {
 432         struct batadv_priv *bat_priv;
 433         struct batadv_hard_iface *primary_if = NULL;
 434
 435         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 436                 goto out;
 437
 438         bat_priv = netdev_priv(hard_iface->soft_iface);
 439
 440         bat_priv->algo_ops->iface.update_mac(hard_iface);
 441         hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
 442
 443         /* the first active interface becomes our primary interface or
 444          * the next active interface after the old primary interface was removed
 445          */
 446         primary_if = batadv_primary_if_get_selected(bat_priv);
 447         if (!primary_if)
 448                 batadv_primary_if_select(bat_priv, hard_iface);
 449
 450         batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
 451                     hard_iface->net_dev->name);
 452
 453         batadv_update_min_mtu(hard_iface->soft_iface);
 454
 455         if (bat_priv->algo_ops->iface.activate)
 456                 bat_priv->algo_ops->iface.activate(hard_iface);
 457
 458 out:
 459         if (primary_if)
 460                 batadv_hardif_put(primary_if);
 461 }
 462
 463 static void
 464 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
 465 {
 466         if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 467             (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 468                 return;
 469
 470         hard_iface->if_status = BATADV_IF_INACTIVE;
 471
 472         batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
 473                     hard_iface->net_dev->name);
 474
 475         batadv_update_min_mtu(hard_iface->soft_iface);
 476 }
 477
 478 /**
 479  * batadv_master_del_slave - remove hard_iface from the current master interface
 480  * @slave: the interface enslaved in another master
 481  * @master: the master from which slave has to be removed
 482  *
 483  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
 484  * is free'd and master can correctly change its internal state.
 485  *
 486  * Return: 0 on success, a negative value representing the error otherwise
 487  */
 488 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
 489                                    struct net_device *master)
 490 {
 491         int ret;
 492
 493         if (!master)
 494                 return 0;
 495
 496         ret = -EBUSY;
 497         if (master->netdev_ops->ndo_del_slave)
 498                 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
 499
 500         return ret;
 501 }
 502
 503 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 504                                    struct net *net, const char *iface_name)
 505 {
 506         struct batadv_priv *bat_priv;
 507         struct net_device *soft_iface, *master;
 508         __be16 ethertype = htons(ETH_P_BATMAN);
 509         int max_header_len = batadv_max_header_len();
 510         int ret;
 511
 512         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 513                 goto out;
 514
 515         kref_get(&hard_iface->refcount);
 516
 517         soft_iface = dev_get_by_name(net, iface_name);
 518
 519         if (!soft_iface) {
 520                 soft_iface = batadv_softif_create(net, iface_name);
 521
 522                 if (!soft_iface) {
 523                         ret = -ENOMEM;
 524                         goto err;
 525                 }
 526
 527                 /* dev_get_by_name() increases the reference counter for us */
 528                 dev_hold(soft_iface);
 529         }
 530
 531         if (!batadv_softif_is_valid(soft_iface)) {
 532                 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
 533                        soft_iface->name);
 534                 ret = -EINVAL;
 535                 goto err_dev;
 536         }
 537
 538         /* check if the interface is enslaved in another virtual one and
 539          * in that case unlink it first
 540          */
 541         master = netdev_master_upper_dev_get(hard_iface->net_dev);
 542         ret = batadv_master_del_slave(hard_iface, master);
 543         if (ret)
 544                 goto err_dev;
 545
 546         hard_iface->soft_iface = soft_iface;
 547         bat_priv = netdev_priv(hard_iface->soft_iface);
 548
 549         if (bat_priv->num_ifaces >= UINT_MAX) {
 550                 ret = -ENOSPC;
 551                 goto err_dev;
 552         }
 553
 554         ret = netdev_master_upper_dev_link(hard_iface->net_dev,
 555                                            soft_iface, NULL, NULL);
 556         if (ret)
 557                 goto err_dev;
 558
 559         ret = bat_priv->algo_ops->iface.enable(hard_iface);
 560         if (ret < 0)
 561                 goto err_upper;
 562
 563         hard_iface->if_num = bat_priv->num_ifaces;
 564         bat_priv->num_ifaces++;
 565         hard_iface->if_status = BATADV_IF_INACTIVE;
 566         ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
 567         if (ret < 0) {
 568                 bat_priv->algo_ops->iface.disable(hard_iface);
 569                 bat_priv->num_ifaces--;
 570                 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 571                 goto err_upper;
 572         }
 573
 574         kref_get(&hard_iface->refcount);
 575         hard_iface->batman_adv_ptype.type = ethertype;
 576         hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
 577         hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
 578         dev_add_pack(&hard_iface->batman_adv_ptype);
 579
 580         batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
 581                     hard_iface->net_dev->name);
 582
 583         if (atomic_read(&bat_priv->fragmentation) &&
 584             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 585                 batadv_info(hard_iface->soft_iface,
 586                             "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",
 587                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 588                             ETH_DATA_LEN + max_header_len);
 589
 590         if (!atomic_read(&bat_priv->fragmentation) &&
 591             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 592                 batadv_info(hard_iface->soft_iface,
 593                             "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",
 594                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 595                             ETH_DATA_LEN + max_header_len);
 596
 597         if (batadv_hardif_is_iface_up(hard_iface))
 598                 batadv_hardif_activate_interface(hard_iface);
 599         else
 600                 batadv_err(hard_iface->soft_iface,
 601                            "Not using interface %s (retrying later): interface not active\n",
 602                            hard_iface->net_dev->name);
 603
 604         batadv_hardif_recalc_extra_skbroom(soft_iface);
 605
 606         if (bat_priv->algo_ops->iface.enabled)
 607                 bat_priv->algo_ops->iface.enabled(hard_iface);
 608
 609 out:
 610         return 0;
 611
 612 err_upper:
 613         netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
 614 err_dev:
 615         hard_iface->soft_iface = NULL;
 616         dev_put(soft_iface);
 617 err:
 618         batadv_hardif_put(hard_iface);
 619         return ret;
 620 }
 621
 622 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
 623                                      enum batadv_hard_if_cleanup autodel)
 624 {
 625         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 626         struct batadv_hard_iface *primary_if = NULL;
 627
 628         batadv_hardif_deactivate_interface(hard_iface);
 629
 630         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 631                 goto out;
 632
 633         batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
 634                     hard_iface->net_dev->name);
 635         dev_remove_pack(&hard_iface->batman_adv_ptype);
 636         batadv_hardif_put(hard_iface);
 637
 638         bat_priv->num_ifaces--;
 639         batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
 640
 641         primary_if = batadv_primary_if_get_selected(bat_priv);
 642         if (hard_iface == primary_if) {
 643                 struct batadv_hard_iface *new_if;
 644
 645                 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
 646                 batadv_primary_if_select(bat_priv, new_if);
 647
 648                 if (new_if)
 649                         batadv_hardif_put(new_if);
 650         }
 651
 652         bat_priv->algo_ops->iface.disable(hard_iface);
 653         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 654
 655         /* delete all references to this hard_iface */
 656         batadv_purge_orig_ref(bat_priv);
 657         batadv_purge_outstanding_packets(bat_priv, hard_iface);
 658         dev_put(hard_iface->soft_iface);
 659
 660         netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
 661         batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
 662
 663         /* nobody uses this interface anymore */
 664         if (bat_priv->num_ifaces == 0) {
 665                 batadv_gw_check_client_stop(bat_priv);
 666
 667                 if (autodel == BATADV_IF_CLEANUP_AUTO)
 668                         batadv_softif_destroy_sysfs(hard_iface->soft_iface);
 669         }
 670
 671         hard_iface->soft_iface = NULL;
 672         batadv_hardif_put(hard_iface);
 673
 674 out:
 675         if (primary_if)
 676                 batadv_hardif_put(primary_if);
 677 }
 678
 679 static struct batadv_hard_iface *
 680 batadv_hardif_add_interface(struct net_device *net_dev)
 681 {
 682         struct batadv_hard_iface *hard_iface;
 683         int ret;
 684
 685         ASSERT_RTNL();
 686
 687         if (!batadv_is_valid_iface(net_dev))
 688                 goto out;
 689
 690         dev_hold(net_dev);
 691
 692         hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
 693         if (!hard_iface)
 694                 goto release_dev;
 695
 696         ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
 697         if (ret)
 698                 goto free_if;
 699
 700         hard_iface->if_num = 0;
 701         hard_iface->net_dev = net_dev;
 702         hard_iface->soft_iface = NULL;
 703         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 704
 705         ret = batadv_debugfs_add_hardif(hard_iface);
 706         if (ret)
 707                 goto free_sysfs;
 708
 709         INIT_LIST_HEAD(&hard_iface->list);
 710         INIT_HLIST_HEAD(&hard_iface->neigh_list);
 711
 712         mutex_init(&hard_iface->bat_iv.ogm_buff_mutex);
 713         spin_lock_init(&hard_iface->neigh_list_lock);
 714         kref_init(&hard_iface->refcount);
 715
 716         hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
 717         if (batadv_is_wifi_netdev(net_dev))
 718                 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
 719
 720         batadv_v_hardif_init(hard_iface);
 721
 722         batadv_check_known_mac_addr(hard_iface->net_dev);
 723         kref_get(&hard_iface->refcount);
 724         list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
 725
 726         return hard_iface;
 727
 728 free_sysfs:
 729         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 730 free_if:
 731         kfree(hard_iface);
 732 release_dev:
 733         dev_put(net_dev);
 734 out:
 735         return NULL;
 736 }
 737
 738 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
 739 {
 740         ASSERT_RTNL();
 741
 742         /* first deactivate interface */
 743         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 744                 batadv_hardif_disable_interface(hard_iface,
 745                                                 BATADV_IF_CLEANUP_KEEP);
 746
 747         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 748                 return;
 749
 750         hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
 751         batadv_debugfs_del_hardif(hard_iface);
 752         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 753         batadv_hardif_put(hard_iface);
 754 }
 755
 756 void batadv_hardif_remove_interfaces(void)
 757 {
 758         struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
 759
 760         rtnl_lock();
 761         list_for_each_entry_safe(hard_iface, hard_iface_tmp,
 762                                  &batadv_hardif_list, list) {
 763                 list_del_rcu(&hard_iface->list);
 764                 batadv_hardif_remove_interface(hard_iface);
 765         }
 766         rtnl_unlock();
 767 }
 768
 769 /**
 770  * batadv_hard_if_event_softif() - Handle events for soft interfaces
 771  * @event: NETDEV_* event to handle
 772  * @net_dev: net_device which generated an event
 773  *
 774  * Return: NOTIFY_* result
 775  */
 776 static int batadv_hard_if_event_softif(unsigned long event,
 777                                        struct net_device *net_dev)
 778 {
 779         struct batadv_priv *bat_priv;
 780
 781         switch (event) {
 782         case NETDEV_REGISTER:
 783                 batadv_sysfs_add_meshif(net_dev);
 784                 bat_priv = netdev_priv(net_dev);
 785                 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
 786                 break;
 787         case NETDEV_CHANGENAME:
 788                 batadv_debugfs_rename_meshif(net_dev);
 789                 break;
 790         }
 791
 792         return NOTIFY_DONE;
 793 }
 794
 795 static int batadv_hard_if_event(struct notifier_block *this,
 796                                 unsigned long event, void *ptr)
 797 {
 798         struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
 799         struct batadv_hard_iface *hard_iface;
 800         struct batadv_hard_iface *primary_if = NULL;
 801         struct batadv_priv *bat_priv;
 802
 803         if (batadv_softif_is_valid(net_dev))
 804                 return batadv_hard_if_event_softif(event, net_dev);
 805
 806         hard_iface = batadv_hardif_get_by_netdev(net_dev);
 807         if (!hard_iface && (event == NETDEV_REGISTER ||
 808                             event == NETDEV_POST_TYPE_CHANGE))
 809                 hard_iface = batadv_hardif_add_interface(net_dev);
 810
 811         if (!hard_iface)
 812                 goto out;
 813
 814         switch (event) {
 815         case NETDEV_UP:
 816                 batadv_hardif_activate_interface(hard_iface);
 817                 break;
 818         case NETDEV_GOING_DOWN:
 819         case NETDEV_DOWN:
 820                 batadv_hardif_deactivate_interface(hard_iface);
 821                 break;
 822         case NETDEV_UNREGISTER:
 823         case NETDEV_PRE_TYPE_CHANGE:
 824                 list_del_rcu(&hard_iface->list);
 825
 826                 batadv_hardif_remove_interface(hard_iface);
 827                 break;
 828         case NETDEV_CHANGEMTU:
 829                 if (hard_iface->soft_iface)
 830                         batadv_update_min_mtu(hard_iface->soft_iface);
 831                 break;
 832         case NETDEV_CHANGEADDR:
 833                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 834                         goto hardif_put;
 835
 836                 batadv_check_known_mac_addr(hard_iface->net_dev);
 837
 838                 bat_priv = netdev_priv(hard_iface->soft_iface);
 839                 bat_priv->algo_ops->iface.update_mac(hard_iface);
 840
 841                 primary_if = batadv_primary_if_get_selected(bat_priv);
 842                 if (!primary_if)
 843                         goto hardif_put;
 844
 845                 if (hard_iface == primary_if)
 846                         batadv_primary_if_update_addr(bat_priv, NULL);
 847                 break;
 848         case NETDEV_CHANGENAME:
 849                 batadv_debugfs_rename_hardif(hard_iface);
 850                 break;
 851         default:
 852                 break;
 853         }
 854
 855 hardif_put:
 856         batadv_hardif_put(hard_iface);
 857 out:
 858         if (primary_if)
 859                 batadv_hardif_put(primary_if);
 860         return NOTIFY_DONE;
 861 }
 862
 863 struct notifier_block batadv_hard_if_notifier = {
 864         .notifier_call = batadv_hard_if_event,
 865 };