net/mac80211/iface.c

   1 /*
   2  * Interface handling (except master interface)
   3  *
   4  * Copyright 2002-2005, Instant802 Networks, Inc.
   5  * Copyright 2005-2006, Devicescape Software, Inc.
   6  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13 #include <linux/kernel.h>
  14 #include <linux/if_arp.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/rtnetlink.h>
  17 #include <net/mac80211.h>
  18 #include "ieee80211_i.h"
  19 #include "sta_info.h"
  20 #include "debugfs_netdev.h"
  21 #include "mesh.h"
  22 #include "led.h"
  23
  24 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
  25 {
  26         int meshhdrlen;
  27         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  28
  29         meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
  30
  31         /* FIX: what would be proper limits for MTU?
  32          * This interface uses 802.3 frames. */
  33         if (new_mtu < 256 ||
  34             new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
  35                 return -EINVAL;
  36         }
  37
  38 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  39         printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
  40 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
  41         dev->mtu = new_mtu;
  42         return 0;
  43 }
  44
  45 static inline int identical_mac_addr_allowed(int type1, int type2)
  46 {
  47         return type1 == NL80211_IFTYPE_MONITOR ||
  48                 type2 == NL80211_IFTYPE_MONITOR ||
  49                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
  50                 (type1 == NL80211_IFTYPE_WDS &&
  51                         (type2 == NL80211_IFTYPE_WDS ||
  52                          type2 == NL80211_IFTYPE_AP)) ||
  53                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
  54                 (type1 == NL80211_IFTYPE_AP_VLAN &&
  55                         (type2 == NL80211_IFTYPE_AP ||
  56                          type2 == NL80211_IFTYPE_AP_VLAN));
  57 }
  58
  59 static int ieee80211_open(struct net_device *dev)
  60 {
  61         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  62         struct ieee80211_sub_if_data *nsdata;
  63         struct ieee80211_local *local = sdata->local;
  64         struct sta_info *sta;
  65         struct ieee80211_if_init_conf conf;
  66         u32 changed = 0;
  67         int res;
  68         bool need_hw_reconfig = 0;
  69         u8 null_addr[ETH_ALEN] = {0};
  70
  71         /* fail early if user set an invalid address */
  72         if (compare_ether_addr(dev->dev_addr, null_addr) &&
  73             !is_valid_ether_addr(dev->dev_addr))
  74                 return -EADDRNOTAVAIL;
  75
  76         /* we hold the RTNL here so can safely walk the list */
  77         list_for_each_entry(nsdata, &local->interfaces, list) {
  78                 struct net_device *ndev = nsdata->dev;
  79
  80                 if (ndev != dev && netif_running(ndev)) {
  81                         /*
  82                          * Allow only a single IBSS interface to be up at any
  83                          * time. This is restricted because beacon distribution
  84                          * cannot work properly if both are in the same IBSS.
  85                          *
  86                          * To remove this restriction we'd have to disallow them
  87                          * from setting the same SSID on different IBSS interfaces
  88                          * belonging to the same hardware. Then, however, we're
  89                          * faced with having to adopt two different TSF timers...
  90                          */
  91                         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
  92                             nsdata->vif.type == NL80211_IFTYPE_ADHOC)
  93                                 return -EBUSY;
  94
  95                         /*
  96                          * The remaining checks are only performed for interfaces
  97                          * with the same MAC address.
  98                          */
  99                         if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
 100                                 continue;
 101
 102                         /*
 103                          * check whether it may have the same address
 104                          */
 105                         if (!identical_mac_addr_allowed(sdata->vif.type,
 106                                                         nsdata->vif.type))
 107                                 return -ENOTUNIQ;
 108
 109                         /*
 110                          * can only add VLANs to enabled APs
 111                          */
 112                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
 113                             nsdata->vif.type == NL80211_IFTYPE_AP)
 114                                 sdata->bss = &nsdata->u.ap;
 115                 }
 116         }
 117
 118         switch (sdata->vif.type) {
 119         case NL80211_IFTYPE_WDS:
 120                 if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
 121                         return -ENOLINK;
 122                 break;
 123         case NL80211_IFTYPE_AP_VLAN:
 124                 if (!sdata->bss)
 125                         return -ENOLINK;
 126                 list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
 127                 break;
 128         case NL80211_IFTYPE_AP:
 129                 sdata->bss = &sdata->u.ap;
 130                 break;
 131         case NL80211_IFTYPE_MESH_POINT:
 132                 if (!ieee80211_vif_is_mesh(&sdata->vif))
 133                         break;
 134                 /* mesh ifaces must set allmulti to forward mcast traffic */
 135                 atomic_inc(&local->iff_allmultis);
 136                 break;
 137         case NL80211_IFTYPE_STATION:
 138         case NL80211_IFTYPE_MONITOR:
 139         case NL80211_IFTYPE_ADHOC:
 140                 /* no special treatment */
 141                 break;
 142         case NL80211_IFTYPE_UNSPECIFIED:
 143         case __NL80211_IFTYPE_AFTER_LAST:
 144                 /* cannot happen */
 145                 WARN_ON(1);
 146                 break;
 147         }
 148
 149         if (local->open_count == 0) {
 150                 res = 0;
 151                 if (local->ops->start)
 152                         res = local->ops->start(local_to_hw(local));
 153                 if (res)
 154                         goto err_del_bss;
 155                 need_hw_reconfig = 1;
 156                 ieee80211_led_radio(local, local->hw.conf.radio_enabled);
 157         }
 158
 159         /*
 160          * Check all interfaces and copy the hopefully now-present
 161          * MAC address to those that have the special null one.
 162          */
 163         list_for_each_entry(nsdata, &local->interfaces, list) {
 164                 struct net_device *ndev = nsdata->dev;
 165
 166                 /*
 167                  * No need to check netif_running since we do not allow
 168                  * it to start up with this invalid address.
 169                  */
 170                 if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
 171                         memcpy(ndev->dev_addr,
 172                                local->hw.wiphy->perm_addr,
 173                                ETH_ALEN);
 174         }
 175
 176         if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
 177                 memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
 178                        ETH_ALEN);
 179
 180         /*
 181          * Validate the MAC address for this device.
 182          */
 183         if (!is_valid_ether_addr(dev->dev_addr)) {
 184                 if (!local->open_count && local->ops->stop)
 185                         local->ops->stop(local_to_hw(local));
 186                 return -EADDRNOTAVAIL;
 187         }
 188
 189         switch (sdata->vif.type) {
 190         case NL80211_IFTYPE_AP_VLAN:
 191                 /* no need to tell driver */
 192                 break;
 193         case NL80211_IFTYPE_MONITOR:
 194                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 195                         local->cooked_mntrs++;
 196                         break;
 197                 }
 198
 199                 /* must be before the call to ieee80211_configure_filter */
 200                 local->monitors++;
 201                 if (local->monitors == 1)
 202                         local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
 203
 204                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 205                         local->fif_fcsfail++;
 206                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 207                         local->fif_plcpfail++;
 208                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 209                         local->fif_control++;
 210                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 211                         local->fif_other_bss++;
 212
 213                 netif_addr_lock_bh(local->mdev);
 214                 ieee80211_configure_filter(local);
 215                 netif_addr_unlock_bh(local->mdev);
 216                 break;
 217         case NL80211_IFTYPE_STATION:
 218         case NL80211_IFTYPE_ADHOC:
 219                 sdata->u.sta.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
 220                 /* fall through */
 221         default:
 222                 conf.vif = &sdata->vif;
 223                 conf.type = sdata->vif.type;
 224                 conf.mac_addr = dev->dev_addr;
 225                 res = local->ops->add_interface(local_to_hw(local), &conf);
 226                 if (res)
 227                         goto err_stop;
 228
 229                 if (ieee80211_vif_is_mesh(&sdata->vif))
 230                         ieee80211_start_mesh(sdata);
 231                 changed |= ieee80211_reset_erp_info(sdata);
 232                 ieee80211_bss_info_change_notify(sdata, changed);
 233                 ieee80211_enable_keys(sdata);
 234
 235                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 236                     !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
 237                         netif_carrier_off(dev);
 238                 else
 239                         netif_carrier_on(dev);
 240         }
 241
 242         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
 243                 /* Create STA entry for the WDS peer */
 244                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
 245                                      GFP_KERNEL);
 246                 if (!sta) {
 247                         res = -ENOMEM;
 248                         goto err_del_interface;
 249                 }
 250
 251                 /* no locking required since STA is not live yet */
 252                 sta->flags |= WLAN_STA_AUTHORIZED;
 253
 254                 res = sta_info_insert(sta);
 255                 if (res) {
 256                         /* STA has been freed */
 257                         goto err_del_interface;
 258                 }
 259         }
 260
 261         if (local->open_count == 0) {
 262                 res = dev_open(local->mdev);
 263                 WARN_ON(res);
 264                 if (res)
 265                         goto err_del_interface;
 266                 tasklet_enable(&local->tx_pending_tasklet);
 267                 tasklet_enable(&local->tasklet);
 268         }
 269
 270         /*
 271          * set_multicast_list will be invoked by the networking core
 272          * which will check whether any increments here were done in
 273          * error and sync them down to the hardware as filter flags.
 274          */
 275         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 276                 atomic_inc(&local->iff_allmultis);
 277
 278         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 279                 atomic_inc(&local->iff_promiscs);
 280
 281         local->open_count++;
 282         if (need_hw_reconfig) {
 283                 ieee80211_hw_config(local);
 284                 /*
 285                  * set default queue parameters so drivers don't
 286                  * need to initialise the hardware if the hardware
 287                  * doesn't start up with sane defaults
 288                  */
 289                 ieee80211_set_wmm_default(sdata);
 290         }
 291
 292         /*
 293          * ieee80211_sta_work is disabled while network interface
 294          * is down. Therefore, some configuration changes may not
 295          * yet be effective. Trigger execution of ieee80211_sta_work
 296          * to fix this.
 297          */
 298         if (sdata->vif.type == NL80211_IFTYPE_STATION ||
 299             sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 300                 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 301                 queue_work(local->hw.workqueue, &ifsta->work);
 302         }
 303
 304         netif_tx_start_all_queues(dev);
 305
 306         return 0;
 307  err_del_interface:
 308         local->ops->remove_interface(local_to_hw(local), &conf);
 309  err_stop:
 310         if (!local->open_count && local->ops->stop)
 311                 local->ops->stop(local_to_hw(local));
 312  err_del_bss:
 313         sdata->bss = NULL;
 314         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 315                 list_del(&sdata->u.vlan.list);
 316         return res;
 317 }
 318
 319 static int ieee80211_stop(struct net_device *dev)
 320 {
 321         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 322         struct ieee80211_local *local = sdata->local;
 323         struct ieee80211_if_init_conf conf;
 324         struct sta_info *sta;
 325
 326         /*
 327          * Stop TX on this interface first.
 328          */
 329         netif_tx_stop_all_queues(dev);
 330
 331         /*
 332          * Now delete all active aggregation sessions.
 333          */
 334         rcu_read_lock();
 335
 336         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 337                 if (sta->sdata == sdata)
 338                         ieee80211_sta_tear_down_BA_sessions(sdata,
 339                                                             sta->sta.addr);
 340         }
 341
 342         rcu_read_unlock();
 343
 344         /*
 345          * Remove all stations associated with this interface.
 346          *
 347          * This must be done before calling ops->remove_interface()
 348          * because otherwise we can later invoke ops->sta_notify()
 349          * whenever the STAs are removed, and that invalidates driver
 350          * assumptions about always getting a vif pointer that is valid
 351          * (because if we remove a STA after ops->remove_interface()
 352          * the driver will have removed the vif info already!)
 353          *
 354          * We could relax this and only unlink the stations from the
 355          * hash table and list but keep them on a per-sdata list that
 356          * will be inserted back again when the interface is brought
 357          * up again, but I don't currently see a use case for that,
 358          * except with WDS which gets a STA entry created when it is
 359          * brought up.
 360          */
 361         sta_info_flush(local, sdata);
 362
 363         /*
 364          * Don't count this interface for promisc/allmulti while it
 365          * is down. dev_mc_unsync() will invoke set_multicast_list
 366          * on the master interface which will sync these down to the
 367          * hardware as filter flags.
 368          */
 369         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 370                 atomic_dec(&local->iff_allmultis);
 371
 372         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 373                 atomic_dec(&local->iff_promiscs);
 374
 375         dev_mc_unsync(local->mdev, dev);
 376
 377         /* APs need special treatment */
 378         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 379                 struct ieee80211_sub_if_data *vlan, *tmp;
 380                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
 381
 382                 /* remove beacon */
 383                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 384                 synchronize_rcu();
 385                 kfree(old_beacon);
 386
 387                 /* down all dependent devices, that is VLANs */
 388                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
 389                                          u.vlan.list)
 390                         dev_close(vlan->dev);
 391                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
 392         }
 393
 394         local->open_count--;
 395
 396         switch (sdata->vif.type) {
 397         case NL80211_IFTYPE_AP_VLAN:
 398                 list_del(&sdata->u.vlan.list);
 399                 /* no need to tell driver */
 400                 break;
 401         case NL80211_IFTYPE_MONITOR:
 402                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 403                         local->cooked_mntrs--;
 404                         break;
 405                 }
 406
 407                 local->monitors--;
 408                 if (local->monitors == 0)
 409                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
 410
 411                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 412                         local->fif_fcsfail--;
 413                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 414                         local->fif_plcpfail--;
 415                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 416                         local->fif_control--;
 417                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 418                         local->fif_other_bss--;
 419
 420                 netif_addr_lock_bh(local->mdev);
 421                 ieee80211_configure_filter(local);
 422                 netif_addr_unlock_bh(local->mdev);
 423                 break;
 424         case NL80211_IFTYPE_STATION:
 425         case NL80211_IFTYPE_ADHOC:
 426                 sdata->u.sta.state = IEEE80211_STA_MLME_DISABLED;
 427                 memset(sdata->u.sta.bssid, 0, ETH_ALEN);
 428                 del_timer_sync(&sdata->u.sta.timer);
 429                 /*
 430                  * If the timer fired while we waited for it, it will have
 431                  * requeued the work. Now the work will be running again
 432                  * but will not rearm the timer again because it checks
 433                  * whether the interface is running, which, at this point,
 434                  * it no longer is.
 435                  */
 436                 cancel_work_sync(&sdata->u.sta.work);
 437                 /*
 438                  * When we get here, the interface is marked down.
 439                  * Call synchronize_rcu() to wait for the RX path
 440                  * should it be using the interface and enqueuing
 441                  * frames at this very time on another CPU.
 442                  */
 443                 synchronize_rcu();
 444                 skb_queue_purge(&sdata->u.sta.skb_queue);
 445
 446                 sdata->u.sta.flags &= ~IEEE80211_STA_PRIVACY_INVOKED;
 447                 kfree(sdata->u.sta.extra_ie);
 448                 sdata->u.sta.extra_ie = NULL;
 449                 sdata->u.sta.extra_ie_len = 0;
 450                 /* fall through */
 451         case NL80211_IFTYPE_MESH_POINT:
 452                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 453                         /* allmulti is always set on mesh ifaces */
 454                         atomic_dec(&local->iff_allmultis);
 455                         ieee80211_stop_mesh(sdata);
 456                 }
 457                 /* fall through */
 458         default:
 459                 if (local->scan_sdata == sdata) {
 460                         if (!local->ops->hw_scan)
 461                                 cancel_delayed_work_sync(&local->scan_work);
 462                         /*
 463                          * The software scan can no longer run now, so we can
 464                          * clear out the scan_sdata reference. However, the
 465                          * hardware scan may still be running. The complete
 466                          * function must be prepared to handle a NULL value.
 467                          */
 468                         local->scan_sdata = NULL;
 469                         /*
 470                          * The memory barrier guarantees that another CPU
 471                          * that is hardware-scanning will now see the fact
 472                          * that this interface is gone.
 473                          */
 474                         smp_mb();
 475                         /*
 476                          * If software scanning, complete the scan but since
 477                          * the scan_sdata is NULL already don't send out a
 478                          * scan event to userspace -- the scan is incomplete.
 479                          */
 480                         if (local->sw_scanning)
 481                                 ieee80211_scan_completed(&local->hw);
 482                 }
 483
 484                 conf.vif = &sdata->vif;
 485                 conf.type = sdata->vif.type;
 486                 conf.mac_addr = dev->dev_addr;
 487                 /* disable all keys for as long as this netdev is down */
 488                 ieee80211_disable_keys(sdata);
 489                 local->ops->remove_interface(local_to_hw(local), &conf);
 490         }
 491
 492         sdata->bss = NULL;
 493
 494         if (local->open_count == 0) {
 495                 if (netif_running(local->mdev))
 496                         dev_close(local->mdev);
 497
 498                 if (local->ops->stop)
 499                         local->ops->stop(local_to_hw(local));
 500
 501                 ieee80211_led_radio(local, 0);
 502
 503                 flush_workqueue(local->hw.workqueue);
 504
 505                 tasklet_disable(&local->tx_pending_tasklet);
 506                 tasklet_disable(&local->tasklet);
 507         }
 508
 509         return 0;
 510 }
 511
 512 static void ieee80211_set_multicast_list(struct net_device *dev)
 513 {
 514         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 515         struct ieee80211_local *local = sdata->local;
 516         int allmulti, promisc, sdata_allmulti, sdata_promisc;
 517
 518         allmulti = !!(dev->flags & IFF_ALLMULTI);
 519         promisc = !!(dev->flags & IFF_PROMISC);
 520         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
 521         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
 522
 523         if (allmulti != sdata_allmulti) {
 524                 if (dev->flags & IFF_ALLMULTI)
 525                         atomic_inc(&local->iff_allmultis);
 526                 else
 527                         atomic_dec(&local->iff_allmultis);
 528                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
 529         }
 530
 531         if (promisc != sdata_promisc) {
 532                 if (dev->flags & IFF_PROMISC)
 533                         atomic_inc(&local->iff_promiscs);
 534                 else
 535                         atomic_dec(&local->iff_promiscs);
 536                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
 537         }
 538
 539         dev_mc_sync(local->mdev, dev);
 540 }
 541
 542 static void ieee80211_if_setup(struct net_device *dev)
 543 {
 544         ether_setup(dev);
 545         dev->hard_start_xmit = ieee80211_subif_start_xmit;
 546         dev->wireless_handlers = &ieee80211_iw_handler_def;
 547         dev->set_multicast_list = ieee80211_set_multicast_list;
 548         dev->change_mtu = ieee80211_change_mtu;
 549         dev->open = ieee80211_open;
 550         dev->stop = ieee80211_stop;
 551         dev->destructor = free_netdev;
 552         /* we will validate the address ourselves in ->open */
 553         dev->validate_addr = NULL;
 554 }
 555 /*
 556  * Called when the netdev is removed or, by the code below, before
 557  * the interface type changes.
 558  */
 559 static void ieee80211_teardown_sdata(struct net_device *dev)
 560 {
 561         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 562         struct ieee80211_local *local = sdata->local;
 563         struct beacon_data *beacon;
 564         struct sk_buff *skb;
 565         int flushed;
 566         int i;
 567
 568         /* free extra data */
 569         ieee80211_free_keys(sdata);
 570
 571         ieee80211_debugfs_remove_netdev(sdata);
 572
 573         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 574                 __skb_queue_purge(&sdata->fragments[i].skb_list);
 575         sdata->fragment_next = 0;
 576
 577         switch (sdata->vif.type) {
 578         case NL80211_IFTYPE_AP:
 579                 beacon = sdata->u.ap.beacon;
 580                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 581                 synchronize_rcu();
 582                 kfree(beacon);
 583
 584                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
 585                         local->total_ps_buffered--;
 586                         dev_kfree_skb(skb);
 587                 }
 588
 589                 break;
 590         case NL80211_IFTYPE_MESH_POINT:
 591                 if (ieee80211_vif_is_mesh(&sdata->vif))
 592                         mesh_rmc_free(sdata);
 593                 break;
 594         case NL80211_IFTYPE_STATION:
 595         case NL80211_IFTYPE_ADHOC:
 596                 kfree(sdata->u.sta.extra_ie);
 597                 kfree(sdata->u.sta.assocreq_ies);
 598                 kfree(sdata->u.sta.assocresp_ies);
 599                 kfree_skb(sdata->u.sta.probe_resp);
 600                 break;
 601         case NL80211_IFTYPE_WDS:
 602         case NL80211_IFTYPE_AP_VLAN:
 603         case NL80211_IFTYPE_MONITOR:
 604                 break;
 605         case NL80211_IFTYPE_UNSPECIFIED:
 606         case __NL80211_IFTYPE_AFTER_LAST:
 607                 BUG();
 608                 break;
 609         }
 610
 611         flushed = sta_info_flush(local, sdata);
 612         WARN_ON(flushed);
 613 }
 614
 615 /*
 616  * Helper function to initialise an interface to a specific type.
 617  */
 618 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
 619                                   enum nl80211_iftype type)
 620 {
 621         /* clear type-dependent union */
 622         memset(&sdata->u, 0, sizeof(sdata->u));
 623
 624         /* and set some type-dependent values */
 625         sdata->vif.type = type;
 626         sdata->dev->hard_start_xmit = ieee80211_subif_start_xmit;
 627         sdata->wdev.iftype = type;
 628
 629         /* only monitor differs */
 630         sdata->dev->type = ARPHRD_ETHER;
 631
 632         switch (type) {
 633         case NL80211_IFTYPE_AP:
 634                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
 635                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
 636                 break;
 637         case NL80211_IFTYPE_STATION:
 638         case NL80211_IFTYPE_ADHOC:
 639                 ieee80211_sta_setup_sdata(sdata);
 640                 break;
 641         case NL80211_IFTYPE_MESH_POINT:
 642                 if (ieee80211_vif_is_mesh(&sdata->vif))
 643                         ieee80211_mesh_init_sdata(sdata);
 644                 break;
 645         case NL80211_IFTYPE_MONITOR:
 646                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 647                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
 648                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 649                                       MONITOR_FLAG_OTHER_BSS;
 650                 break;
 651         case NL80211_IFTYPE_WDS:
 652         case NL80211_IFTYPE_AP_VLAN:
 653                 break;
 654         case NL80211_IFTYPE_UNSPECIFIED:
 655         case __NL80211_IFTYPE_AFTER_LAST:
 656                 BUG();
 657                 break;
 658         }
 659
 660         ieee80211_debugfs_add_netdev(sdata);
 661 }
 662
 663 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 664                              enum nl80211_iftype type)
 665 {
 666         ASSERT_RTNL();
 667
 668         if (type == sdata->vif.type)
 669                 return 0;
 670
 671         /*
 672          * We could, here, on changes between IBSS/STA/MESH modes,
 673          * invoke an MLME function instead that disassociates etc.
 674          * and goes into the requested mode.
 675          */
 676
 677         if (netif_running(sdata->dev))
 678                 return -EBUSY;
 679
 680         /* Purge and reset type-dependent state. */
 681         ieee80211_teardown_sdata(sdata->dev);
 682         ieee80211_setup_sdata(sdata, type);
 683
 684         /* reset some values that shouldn't be kept across type changes */
 685         sdata->bss_conf.basic_rates =
 686                 ieee80211_mandatory_rates(sdata->local,
 687                         sdata->local->hw.conf.channel->band);
 688         sdata->drop_unencrypted = 0;
 689
 690         return 0;
 691 }
 692
 693 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 694                      struct net_device **new_dev, enum nl80211_iftype type,
 695                      struct vif_params *params)
 696 {
 697         struct net_device *ndev;
 698         struct ieee80211_sub_if_data *sdata = NULL;
 699         int ret, i;
 700
 701         ASSERT_RTNL();
 702
 703         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 704                             name, ieee80211_if_setup);
 705         if (!ndev)
 706                 return -ENOMEM;
 707
 708         ndev->needed_headroom = local->tx_headroom +
 709                                 4*6 /* four MAC addresses */
 710                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 711                                 + 6 /* mesh */
 712                                 + 8 /* rfc1042/bridge tunnel */
 713                                 - ETH_HLEN /* ethernet hard_header_len */
 714                                 + IEEE80211_ENCRYPT_HEADROOM;
 715         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 716
 717         ret = dev_alloc_name(ndev, ndev->name);
 718         if (ret < 0)
 719                 goto fail;
 720
 721         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 722         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 723
 724         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 725         sdata = netdev_priv(ndev);
 726         ndev->ieee80211_ptr = &sdata->wdev;
 727
 728         /* initialise type-independent data */
 729         sdata->wdev.wiphy = local->hw.wiphy;
 730         sdata->local = local;
 731         sdata->dev = ndev;
 732
 733         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 734                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 735
 736         INIT_LIST_HEAD(&sdata->key_list);
 737
 738         sdata->force_unicast_rateidx = -1;
 739         sdata->max_ratectrl_rateidx = -1;
 740
 741         /* setup type-dependent data */
 742         ieee80211_setup_sdata(sdata, type);
 743
 744         ret = register_netdevice(ndev);
 745         if (ret)
 746                 goto fail;
 747
 748         ndev->uninit = ieee80211_teardown_sdata;
 749
 750         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 751             params && params->mesh_id_len)
 752                 ieee80211_sdata_set_mesh_id(sdata,
 753                                             params->mesh_id_len,
 754                                             params->mesh_id);
 755
 756         list_add_tail_rcu(&sdata->list, &local->interfaces);
 757
 758         if (new_dev)
 759                 *new_dev = ndev;
 760
 761         return 0;
 762
 763  fail:
 764         free_netdev(ndev);
 765         return ret;
 766 }
 767
 768 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 769 {
 770         ASSERT_RTNL();
 771
 772         list_del_rcu(&sdata->list);
 773         synchronize_rcu();
 774         unregister_netdevice(sdata->dev);
 775 }
 776
 777 /*
 778  * Remove all interfaces, may only be called at hardware unregistration
 779  * time because it doesn't do RCU-safe list removals.
 780  */
 781 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 782 {
 783         struct ieee80211_sub_if_data *sdata, *tmp;
 784
 785         ASSERT_RTNL();
 786
 787         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 788                 list_del(&sdata->list);
 789                 unregister_netdevice(sdata->dev);
 790         }
 791 }