net/batman-adv/hard-interface.c

   1 /* Copyright (C) 2007-2015 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/byteorder/generic.h>
  22 #include <linux/errno.h>
  23 #include <linux/fs.h>
  24 #include <linux/if_arp.h>
  25 #include <linux/if_ether.h>
  26 #include <linux/if.h>
  27 #include <linux/kernel.h>
  28 #include <linux/list.h>
  29 #include <linux/mutex.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/printk.h>
  32 #include <linux/rculist.h>
  33 #include <linux/rtnetlink.h>
  34 #include <linux/slab.h>
  35 #include <linux/workqueue.h>
  36 #include <net/net_namespace.h>
  37
  38 #include "bridge_loop_avoidance.h"
  39 #include "debugfs.h"
  40 #include "distributed-arp-table.h"
  41 #include "gateway_client.h"
  42 #include "originator.h"
  43 #include "packet.h"
  44 #include "send.h"
  45 #include "soft-interface.h"
  46 #include "sysfs.h"
  47 #include "translation-table.h"
  48
  49 /**
  50  * batadv_hardif_release - release hard interface from lists and queue for
  51  *  free after rcu grace period
  52  * @hard_iface: the hard interface to free
  53  */
  54 void batadv_hardif_release(struct batadv_hard_iface *hard_iface)
  55 {
  56         dev_put(hard_iface->net_dev);
  57
  58         kfree_rcu(hard_iface, rcu);
  59 }
  60
  61 struct batadv_hard_iface *
  62 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
  63 {
  64         struct batadv_hard_iface *hard_iface;
  65
  66         rcu_read_lock();
  67         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
  68                 if (hard_iface->net_dev == net_dev &&
  69                     atomic_inc_not_zero(&hard_iface->refcount))
  70                         goto out;
  71         }
  72
  73         hard_iface = NULL;
  74
  75 out:
  76         rcu_read_unlock();
  77         return hard_iface;
  78 }
  79
  80 /**
  81  * batadv_mutual_parents - check if two devices are each others parent
  82  * @dev1: 1st net_device
  83  * @dev2: 2nd net_device
  84  *
  85  * veth devices come in pairs and each is the parent of the other!
  86  *
  87  * Return: true if the devices are each others parent, otherwise false
  88  */
  89 static bool batadv_mutual_parents(const struct net_device *dev1,
  90                                   const struct net_device *dev2)
  91 {
  92         int dev1_parent_iflink = dev_get_iflink(dev1);
  93         int dev2_parent_iflink = dev_get_iflink(dev2);
  94
  95         if (!dev1_parent_iflink || !dev2_parent_iflink)
  96                 return false;
  97
  98         return (dev1_parent_iflink == dev2->ifindex) &&
  99                (dev2_parent_iflink == dev1->ifindex);
 100 }
 101
 102 /**
 103  * batadv_is_on_batman_iface - check if a device is a batman iface descendant
 104  * @net_dev: the device to check
 105  *
 106  * If the user creates any virtual device on top of a batman-adv interface, it
 107  * is important to prevent this new interface to be used to create a new mesh
 108  * network (this behaviour would lead to a batman-over-batman configuration).
 109  * This function recursively checks all the fathers of the device passed as
 110  * argument looking for a batman-adv soft interface.
 111  *
 112  * Returns true if the device is descendant of a batman-adv mesh interface (or
 113  * if it is a batman-adv interface itself), false otherwise
 114  */
 115 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
 116 {
 117         struct net_device *parent_dev;
 118         bool ret;
 119
 120         /* check if this is a batman-adv mesh interface */
 121         if (batadv_softif_is_valid(net_dev))
 122                 return true;
 123
 124         /* no more parents..stop recursion */
 125         if (dev_get_iflink(net_dev) == 0 ||
 126             dev_get_iflink(net_dev) == net_dev->ifindex)
 127                 return false;
 128
 129         /* recurse over the parent device */
 130         parent_dev = __dev_get_by_index(&init_net, dev_get_iflink(net_dev));
 131         /* if we got a NULL parent_dev there is something broken.. */
 132         if (!parent_dev) {
 133                 pr_err("Cannot find parent device\n");
 134                 return false;
 135         }
 136
 137         if (batadv_mutual_parents(net_dev, parent_dev))
 138                 return false;
 139
 140         ret = batadv_is_on_batman_iface(parent_dev);
 141
 142         return ret;
 143 }
 144
 145 static int batadv_is_valid_iface(const struct net_device *net_dev)
 146 {
 147         if (net_dev->flags & IFF_LOOPBACK)
 148                 return 0;
 149
 150         if (net_dev->type != ARPHRD_ETHER)
 151                 return 0;
 152
 153         if (net_dev->addr_len != ETH_ALEN)
 154                 return 0;
 155
 156         /* no batman over batman */
 157         if (batadv_is_on_batman_iface(net_dev))
 158                 return 0;
 159
 160         return 1;
 161 }
 162
 163 /**
 164  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
 165  *  interface
 166  * @net_device: the device to check
 167  *
 168  * Returns true if the net device is a 802.11 wireless device, false otherwise.
 169  */
 170 bool batadv_is_wifi_netdev(struct net_device *net_device)
 171 {
 172         if (!net_device)
 173                 return false;
 174
 175 #ifdef CONFIG_WIRELESS_EXT
 176         /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
 177          * check for wireless_handlers != NULL
 178          */
 179         if (net_device->wireless_handlers)
 180                 return true;
 181 #endif
 182
 183         /* cfg80211 drivers have to set ieee80211_ptr */
 184         if (net_device->ieee80211_ptr)
 185                 return true;
 186
 187         return false;
 188 }
 189
 190 static struct batadv_hard_iface *
 191 batadv_hardif_get_active(const struct net_device *soft_iface)
 192 {
 193         struct batadv_hard_iface *hard_iface;
 194
 195         rcu_read_lock();
 196         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 197                 if (hard_iface->soft_iface != soft_iface)
 198                         continue;
 199
 200                 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
 201                     atomic_inc_not_zero(&hard_iface->refcount))
 202                         goto out;
 203         }
 204
 205         hard_iface = NULL;
 206
 207 out:
 208         rcu_read_unlock();
 209         return hard_iface;
 210 }
 211
 212 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
 213                                           struct batadv_hard_iface *oldif)
 214 {
 215         struct batadv_hard_iface *primary_if;
 216
 217         primary_if = batadv_primary_if_get_selected(bat_priv);
 218         if (!primary_if)
 219                 goto out;
 220
 221         batadv_dat_init_own_addr(bat_priv, primary_if);
 222         batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
 223 out:
 224         if (primary_if)
 225                 batadv_hardif_free_ref(primary_if);
 226 }
 227
 228 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
 229                                      struct batadv_hard_iface *new_hard_iface)
 230 {
 231         struct batadv_hard_iface *curr_hard_iface;
 232
 233         ASSERT_RTNL();
 234
 235         if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
 236                 new_hard_iface = NULL;
 237
 238         curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
 239         rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
 240
 241         if (!new_hard_iface)
 242                 goto out;
 243
 244         bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
 245         batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
 246
 247 out:
 248         if (curr_hard_iface)
 249                 batadv_hardif_free_ref(curr_hard_iface);
 250 }
 251
 252 static bool
 253 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
 254 {
 255         if (hard_iface->net_dev->flags & IFF_UP)
 256                 return true;
 257
 258         return false;
 259 }
 260
 261 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
 262 {
 263         const struct batadv_hard_iface *hard_iface;
 264
 265         rcu_read_lock();
 266         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 267                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 268                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 269                         continue;
 270
 271                 if (hard_iface->net_dev == net_dev)
 272                         continue;
 273
 274                 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
 275                                         net_dev->dev_addr))
 276                         continue;
 277
 278                 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
 279                         net_dev->dev_addr, hard_iface->net_dev->name);
 280                 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
 281         }
 282         rcu_read_unlock();
 283 }
 284
 285 /**
 286  * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
 287  * @soft_iface: netdev struct of the mesh interface
 288  */
 289 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
 290 {
 291         const struct batadv_hard_iface *hard_iface;
 292         unsigned short lower_header_len = ETH_HLEN;
 293         unsigned short lower_headroom = 0;
 294         unsigned short lower_tailroom = 0;
 295         unsigned short needed_headroom;
 296
 297         rcu_read_lock();
 298         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 299                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 300                         continue;
 301
 302                 if (hard_iface->soft_iface != soft_iface)
 303                         continue;
 304
 305                 lower_header_len = max_t(unsigned short, lower_header_len,
 306                                          hard_iface->net_dev->hard_header_len);
 307
 308                 lower_headroom = max_t(unsigned short, lower_headroom,
 309                                        hard_iface->net_dev->needed_headroom);
 310
 311                 lower_tailroom = max_t(unsigned short, lower_tailroom,
 312                                        hard_iface->net_dev->needed_tailroom);
 313         }
 314         rcu_read_unlock();
 315
 316         needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
 317         needed_headroom += batadv_max_header_len();
 318
 319         /* fragmentation headers don't strip the unicast/... header */
 320         needed_headroom += sizeof(struct batadv_frag_packet);
 321
 322         soft_iface->needed_headroom = needed_headroom;
 323         soft_iface->needed_tailroom = lower_tailroom;
 324 }
 325
 326 int batadv_hardif_min_mtu(struct net_device *soft_iface)
 327 {
 328         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 329         const struct batadv_hard_iface *hard_iface;
 330         int min_mtu = INT_MAX;
 331
 332         rcu_read_lock();
 333         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 334                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 335                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 336                         continue;
 337
 338                 if (hard_iface->soft_iface != soft_iface)
 339                         continue;
 340
 341                 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
 342         }
 343         rcu_read_unlock();
 344
 345         if (atomic_read(&bat_priv->fragmentation) == 0)
 346                 goto out;
 347
 348         /* with fragmentation enabled the maximum size of internally generated
 349          * packets such as translation table exchanges or tvlv containers, etc
 350          * has to be calculated
 351          */
 352         min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
 353         min_mtu -= sizeof(struct batadv_frag_packet);
 354         min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
 355
 356 out:
 357         /* report to the other components the maximum amount of bytes that
 358          * batman-adv can send over the wire (without considering the payload
 359          * overhead). For example, this value is used by TT to compute the
 360          * maximum local table table size
 361          */
 362         atomic_set(&bat_priv->packet_size_max, min_mtu);
 363
 364         /* the real soft-interface MTU is computed by removing the payload
 365          * overhead from the maximum amount of bytes that was just computed.
 366          *
 367          * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
 368          */
 369         return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
 370 }
 371
 372 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
 373 void batadv_update_min_mtu(struct net_device *soft_iface)
 374 {
 375         soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
 376
 377         /* Check if the local translate table should be cleaned up to match a
 378          * new (and smaller) MTU.
 379          */
 380         batadv_tt_local_resize_to_mtu(soft_iface);
 381 }
 382
 383 static void
 384 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 385 {
 386         struct batadv_priv *bat_priv;
 387         struct batadv_hard_iface *primary_if = NULL;
 388
 389         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 390                 goto out;
 391
 392         bat_priv = netdev_priv(hard_iface->soft_iface);
 393
 394         bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
 395         hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
 396
 397         /* the first active interface becomes our primary interface or
 398          * the next active interface after the old primary interface was removed
 399          */
 400         primary_if = batadv_primary_if_get_selected(bat_priv);
 401         if (!primary_if)
 402                 batadv_primary_if_select(bat_priv, hard_iface);
 403
 404         batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
 405                     hard_iface->net_dev->name);
 406
 407         batadv_update_min_mtu(hard_iface->soft_iface);
 408
 409 out:
 410         if (primary_if)
 411                 batadv_hardif_free_ref(primary_if);
 412 }
 413
 414 static void
 415 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
 416 {
 417         if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
 418             (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
 419                 return;
 420
 421         hard_iface->if_status = BATADV_IF_INACTIVE;
 422
 423         batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
 424                     hard_iface->net_dev->name);
 425
 426         batadv_update_min_mtu(hard_iface->soft_iface);
 427 }
 428
 429 /**
 430  * batadv_master_del_slave - remove hard_iface from the current master interface
 431  * @slave: the interface enslaved in another master
 432  * @master: the master from which slave has to be removed
 433  *
 434  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
 435  * is free'd and master can correctly change its internal state.
 436  * Return 0 on success, a negative value representing the error otherwise
 437  */
 438 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
 439                                    struct net_device *master)
 440 {
 441         int ret;
 442
 443         if (!master)
 444                 return 0;
 445
 446         ret = -EBUSY;
 447         if (master->netdev_ops->ndo_del_slave)
 448                 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
 449
 450         return ret;
 451 }
 452
 453 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 454                                    const char *iface_name)
 455 {
 456         struct batadv_priv *bat_priv;
 457         struct net_device *soft_iface, *master;
 458         __be16 ethertype = htons(ETH_P_BATMAN);
 459         int max_header_len = batadv_max_header_len();
 460         int ret;
 461
 462         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 463                 goto out;
 464
 465         if (!atomic_inc_not_zero(&hard_iface->refcount))
 466                 goto out;
 467
 468         soft_iface = dev_get_by_name(&init_net, iface_name);
 469
 470         if (!soft_iface) {
 471                 soft_iface = batadv_softif_create(iface_name);
 472
 473                 if (!soft_iface) {
 474                         ret = -ENOMEM;
 475                         goto err;
 476                 }
 477
 478                 /* dev_get_by_name() increases the reference counter for us */
 479                 dev_hold(soft_iface);
 480         }
 481
 482         if (!batadv_softif_is_valid(soft_iface)) {
 483                 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
 484                        soft_iface->name);
 485                 ret = -EINVAL;
 486                 goto err_dev;
 487         }
 488
 489         /* check if the interface is enslaved in another virtual one and
 490          * in that case unlink it first
 491          */
 492         master = netdev_master_upper_dev_get(hard_iface->net_dev);
 493         ret = batadv_master_del_slave(hard_iface, master);
 494         if (ret)
 495                 goto err_dev;
 496
 497         hard_iface->soft_iface = soft_iface;
 498         bat_priv = netdev_priv(hard_iface->soft_iface);
 499
 500         if (bat_priv->num_ifaces >= UINT_MAX) {
 501                 ret = -ENOSPC;
 502                 goto err_dev;
 503         }
 504
 505         ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
 506         if (ret)
 507                 goto err_dev;
 508
 509         ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
 510         if (ret < 0)
 511                 goto err_upper;
 512
 513         hard_iface->if_num = bat_priv->num_ifaces;
 514         bat_priv->num_ifaces++;
 515         hard_iface->if_status = BATADV_IF_INACTIVE;
 516         ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
 517         if (ret < 0) {
 518                 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
 519                 bat_priv->num_ifaces--;
 520                 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 521                 goto err_upper;
 522         }
 523
 524         hard_iface->batman_adv_ptype.type = ethertype;
 525         hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
 526         hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
 527         dev_add_pack(&hard_iface->batman_adv_ptype);
 528
 529         batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
 530                     hard_iface->net_dev->name);
 531
 532         if (atomic_read(&bat_priv->fragmentation) &&
 533             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 534                 batadv_info(hard_iface->soft_iface,
 535                             "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",
 536                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 537                             ETH_DATA_LEN + max_header_len);
 538
 539         if (!atomic_read(&bat_priv->fragmentation) &&
 540             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
 541                 batadv_info(hard_iface->soft_iface,
 542                             "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",
 543                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
 544                             ETH_DATA_LEN + max_header_len);
 545
 546         if (batadv_hardif_is_iface_up(hard_iface))
 547                 batadv_hardif_activate_interface(hard_iface);
 548         else
 549                 batadv_err(hard_iface->soft_iface,
 550                            "Not using interface %s (retrying later): interface not active\n",
 551                            hard_iface->net_dev->name);
 552
 553         batadv_hardif_recalc_extra_skbroom(soft_iface);
 554
 555         /* begin scheduling originator messages on that interface */
 556         batadv_schedule_bat_ogm(hard_iface);
 557
 558 out:
 559         return 0;
 560
 561 err_upper:
 562         netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
 563 err_dev:
 564         hard_iface->soft_iface = NULL;
 565         dev_put(soft_iface);
 566 err:
 567         batadv_hardif_free_ref(hard_iface);
 568         return ret;
 569 }
 570
 571 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
 572                                      enum batadv_hard_if_cleanup autodel)
 573 {
 574         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 575         struct batadv_hard_iface *primary_if = NULL;
 576
 577         batadv_hardif_deactivate_interface(hard_iface);
 578
 579         if (hard_iface->if_status != BATADV_IF_INACTIVE)
 580                 goto out;
 581
 582         batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
 583                     hard_iface->net_dev->name);
 584         dev_remove_pack(&hard_iface->batman_adv_ptype);
 585
 586         bat_priv->num_ifaces--;
 587         batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
 588
 589         primary_if = batadv_primary_if_get_selected(bat_priv);
 590         if (hard_iface == primary_if) {
 591                 struct batadv_hard_iface *new_if;
 592
 593                 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
 594                 batadv_primary_if_select(bat_priv, new_if);
 595
 596                 if (new_if)
 597                         batadv_hardif_free_ref(new_if);
 598         }
 599
 600         bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
 601         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 602
 603         /* delete all references to this hard_iface */
 604         batadv_purge_orig_ref(bat_priv);
 605         batadv_purge_outstanding_packets(bat_priv, hard_iface);
 606         dev_put(hard_iface->soft_iface);
 607
 608         netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
 609         batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
 610
 611         /* nobody uses this interface anymore */
 612         if (bat_priv->num_ifaces == 0) {
 613                 batadv_gw_check_client_stop(bat_priv);
 614
 615                 if (autodel == BATADV_IF_CLEANUP_AUTO)
 616                         batadv_softif_destroy_sysfs(hard_iface->soft_iface);
 617         }
 618
 619         hard_iface->soft_iface = NULL;
 620         batadv_hardif_free_ref(hard_iface);
 621
 622 out:
 623         if (primary_if)
 624                 batadv_hardif_free_ref(primary_if);
 625 }
 626
 627 /**
 628  * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
 629  * @work: work queue item
 630  *
 631  * Free the parts of the hard interface which can not be removed under
 632  * rtnl lock (to prevent deadlock situations).
 633  */
 634 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
 635 {
 636         struct batadv_hard_iface *hard_iface;
 637
 638         hard_iface = container_of(work, struct batadv_hard_iface,
 639                                   cleanup_work);
 640
 641         batadv_debugfs_del_hardif(hard_iface);
 642         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 643         batadv_hardif_free_ref(hard_iface);
 644 }
 645
 646 static struct batadv_hard_iface *
 647 batadv_hardif_add_interface(struct net_device *net_dev)
 648 {
 649         struct batadv_hard_iface *hard_iface;
 650         int ret;
 651
 652         ASSERT_RTNL();
 653
 654         ret = batadv_is_valid_iface(net_dev);
 655         if (ret != 1)
 656                 goto out;
 657
 658         dev_hold(net_dev);
 659
 660         hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
 661         if (!hard_iface)
 662                 goto release_dev;
 663
 664         ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
 665         if (ret)
 666                 goto free_if;
 667
 668         hard_iface->if_num = 0;
 669         hard_iface->net_dev = net_dev;
 670         hard_iface->soft_iface = NULL;
 671         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 672
 673         ret = batadv_debugfs_add_hardif(hard_iface);
 674         if (ret)
 675                 goto free_sysfs;
 676
 677         INIT_LIST_HEAD(&hard_iface->list);
 678         mutex_init(&hard_iface->bat_iv.ogm_buff_mutex);
 679         INIT_WORK(&hard_iface->cleanup_work,
 680                   batadv_hardif_remove_interface_finish);
 681
 682         hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
 683         if (batadv_is_wifi_netdev(net_dev))
 684                 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
 685
 686         /* extra reference for return */
 687         atomic_set(&hard_iface->refcount, 2);
 688
 689         batadv_check_known_mac_addr(hard_iface->net_dev);
 690         list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
 691
 692         return hard_iface;
 693
 694 free_sysfs:
 695         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 696 free_if:
 697         kfree(hard_iface);
 698 release_dev:
 699         dev_put(net_dev);
 700 out:
 701         return NULL;
 702 }
 703
 704 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
 705 {
 706         ASSERT_RTNL();
 707
 708         /* first deactivate interface */
 709         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 710                 batadv_hardif_disable_interface(hard_iface,
 711                                                 BATADV_IF_CLEANUP_AUTO);
 712
 713         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
 714                 return;
 715
 716         hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
 717         queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
 718 }
 719
 720 void batadv_hardif_remove_interfaces(void)
 721 {
 722         struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
 723
 724         rtnl_lock();
 725         list_for_each_entry_safe(hard_iface, hard_iface_tmp,
 726                                  &batadv_hardif_list, list) {
 727                 list_del_rcu(&hard_iface->list);
 728                 batadv_hardif_remove_interface(hard_iface);
 729         }
 730         rtnl_unlock();
 731 }
 732
 733 /**
 734  * batadv_hard_if_event_softif() - Handle events for soft interfaces
 735  * @event: NETDEV_* event to handle
 736  * @net_dev: net_device which generated an event
 737  *
 738  * Return: NOTIFY_* result
 739  */
 740 static int batadv_hard_if_event_softif(unsigned long event,
 741                                        struct net_device *net_dev)
 742 {
 743         struct batadv_priv *bat_priv;
 744
 745         switch (event) {
 746         case NETDEV_REGISTER:
 747                 batadv_sysfs_add_meshif(net_dev);
 748                 bat_priv = netdev_priv(net_dev);
 749                 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
 750                 break;
 751         case NETDEV_CHANGENAME:
 752                 batadv_debugfs_rename_meshif(net_dev);
 753                 break;
 754         }
 755
 756         return NOTIFY_DONE;
 757 }
 758
 759 static int batadv_hard_if_event(struct notifier_block *this,
 760                                 unsigned long event, void *ptr)
 761 {
 762         struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
 763         struct batadv_hard_iface *hard_iface;
 764         struct batadv_hard_iface *primary_if = NULL;
 765         struct batadv_priv *bat_priv;
 766
 767         if (batadv_softif_is_valid(net_dev))
 768                 return batadv_hard_if_event_softif(event, net_dev);
 769
 770         hard_iface = batadv_hardif_get_by_netdev(net_dev);
 771         if (!hard_iface && event == NETDEV_REGISTER)
 772                 hard_iface = batadv_hardif_add_interface(net_dev);
 773
 774         if (!hard_iface)
 775                 goto out;
 776
 777         switch (event) {
 778         case NETDEV_UP:
 779                 batadv_hardif_activate_interface(hard_iface);
 780                 break;
 781         case NETDEV_GOING_DOWN:
 782         case NETDEV_DOWN:
 783                 batadv_hardif_deactivate_interface(hard_iface);
 784                 break;
 785         case NETDEV_UNREGISTER:
 786                 list_del_rcu(&hard_iface->list);
 787
 788                 batadv_hardif_remove_interface(hard_iface);
 789                 break;
 790         case NETDEV_CHANGEMTU:
 791                 if (hard_iface->soft_iface)
 792                         batadv_update_min_mtu(hard_iface->soft_iface);
 793                 break;
 794         case NETDEV_CHANGEADDR:
 795                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
 796                         goto hardif_put;
 797
 798                 batadv_check_known_mac_addr(hard_iface->net_dev);
 799
 800                 bat_priv = netdev_priv(hard_iface->soft_iface);
 801                 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
 802
 803                 primary_if = batadv_primary_if_get_selected(bat_priv);
 804                 if (!primary_if)
 805                         goto hardif_put;
 806
 807                 if (hard_iface == primary_if)
 808                         batadv_primary_if_update_addr(bat_priv, NULL);
 809                 break;
 810         case NETDEV_CHANGENAME:
 811                 batadv_debugfs_rename_hardif(hard_iface);
 812                 break;
 813         default:
 814                 break;
 815         }
 816
 817 hardif_put:
 818         batadv_hardif_free_ref(hard_iface);
 819 out:
 820         if (primary_if)
 821                 batadv_hardif_free_ref(primary_if);
 822         return NOTIFY_DONE;
 823 }
 824
 825 struct notifier_block batadv_hard_if_notifier = {
 826         .notifier_call = batadv_hard_if_event,
 827 };