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         u32 hw_reconf_flags = 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                 /* we're brought up, everything changes */
 156                 hw_reconf_flags = ~0;
 157                 ieee80211_led_radio(local, local->hw.conf.radio_enabled);
 158         }
 159
 160         /*
 161          * Check all interfaces and copy the hopefully now-present
 162          * MAC address to those that have the special null one.
 163          */
 164         list_for_each_entry(nsdata, &local->interfaces, list) {
 165                 struct net_device *ndev = nsdata->dev;
 166
 167                 /*
 168                  * No need to check netif_running since we do not allow
 169                  * it to start up with this invalid address.
 170                  */
 171                 if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
 172                         memcpy(ndev->dev_addr,
 173                                local->hw.wiphy->perm_addr,
 174                                ETH_ALEN);
 175         }
 176
 177         if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
 178                 memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
 179                        ETH_ALEN);
 180
 181         /*
 182          * Validate the MAC address for this device.
 183          */
 184         if (!is_valid_ether_addr(dev->dev_addr)) {
 185                 if (!local->open_count && local->ops->stop)
 186                         local->ops->stop(local_to_hw(local));
 187                 return -EADDRNOTAVAIL;
 188         }
 189
 190         switch (sdata->vif.type) {
 191         case NL80211_IFTYPE_AP_VLAN:
 192                 /* no need to tell driver */
 193                 break;
 194         case NL80211_IFTYPE_MONITOR:
 195                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 196                         local->cooked_mntrs++;
 197                         break;
 198                 }
 199
 200                 /* must be before the call to ieee80211_configure_filter */
 201                 local->monitors++;
 202                 if (local->monitors == 1) {
 203                         local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
 204                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
 205                 }
 206
 207                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 208                         local->fif_fcsfail++;
 209                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 210                         local->fif_plcpfail++;
 211                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 212                         local->fif_control++;
 213                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 214                         local->fif_other_bss++;
 215
 216                 netif_addr_lock_bh(local->mdev);
 217                 ieee80211_configure_filter(local);
 218                 netif_addr_unlock_bh(local->mdev);
 219                 break;
 220         case NL80211_IFTYPE_STATION:
 221         case NL80211_IFTYPE_ADHOC:
 222                 sdata->u.sta.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
 223                 /* fall through */
 224         default:
 225                 conf.vif = &sdata->vif;
 226                 conf.type = sdata->vif.type;
 227                 conf.mac_addr = dev->dev_addr;
 228                 res = local->ops->add_interface(local_to_hw(local), &conf);
 229                 if (res)
 230                         goto err_stop;
 231
 232                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 233                         local->fif_other_bss++;
 234                         netif_addr_lock_bh(local->mdev);
 235                         ieee80211_configure_filter(local);
 236                         netif_addr_unlock_bh(local->mdev);
 237
 238                         ieee80211_start_mesh(sdata);
 239                 }
 240                 changed |= ieee80211_reset_erp_info(sdata);
 241                 ieee80211_bss_info_change_notify(sdata, changed);
 242                 ieee80211_enable_keys(sdata);
 243
 244                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 245                     !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
 246                         netif_carrier_off(dev);
 247                 else
 248                         netif_carrier_on(dev);
 249         }
 250
 251         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
 252                 /* Create STA entry for the WDS peer */
 253                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
 254                                      GFP_KERNEL);
 255                 if (!sta) {
 256                         res = -ENOMEM;
 257                         goto err_del_interface;
 258                 }
 259
 260                 /* no locking required since STA is not live yet */
 261                 sta->flags |= WLAN_STA_AUTHORIZED;
 262
 263                 res = sta_info_insert(sta);
 264                 if (res) {
 265                         /* STA has been freed */
 266                         goto err_del_interface;
 267                 }
 268         }
 269
 270         if (local->open_count == 0) {
 271                 res = dev_open(local->mdev);
 272                 WARN_ON(res);
 273                 if (res)
 274                         goto err_del_interface;
 275                 tasklet_enable(&local->tx_pending_tasklet);
 276                 tasklet_enable(&local->tasklet);
 277         }
 278
 279         /*
 280          * set_multicast_list will be invoked by the networking core
 281          * which will check whether any increments here were done in
 282          * error and sync them down to the hardware as filter flags.
 283          */
 284         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 285                 atomic_inc(&local->iff_allmultis);
 286
 287         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 288                 atomic_inc(&local->iff_promiscs);
 289
 290         local->open_count++;
 291         if (hw_reconf_flags) {
 292                 ieee80211_hw_config(local, hw_reconf_flags);
 293                 /*
 294                  * set default queue parameters so drivers don't
 295                  * need to initialise the hardware if the hardware
 296                  * doesn't start up with sane defaults
 297                  */
 298                 ieee80211_set_wmm_default(sdata);
 299         }
 300
 301         /*
 302          * ieee80211_sta_work is disabled while network interface
 303          * is down. Therefore, some configuration changes may not
 304          * yet be effective. Trigger execution of ieee80211_sta_work
 305          * to fix this.
 306          */
 307         if (sdata->vif.type == NL80211_IFTYPE_STATION ||
 308             sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 309                 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 310                 queue_work(local->hw.workqueue, &ifsta->work);
 311         }
 312
 313         netif_tx_start_all_queues(dev);
 314
 315         return 0;
 316  err_del_interface:
 317         local->ops->remove_interface(local_to_hw(local), &conf);
 318  err_stop:
 319         if (!local->open_count && local->ops->stop)
 320                 local->ops->stop(local_to_hw(local));
 321  err_del_bss:
 322         sdata->bss = NULL;
 323         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 324                 list_del(&sdata->u.vlan.list);
 325         return res;
 326 }
 327
 328 static int ieee80211_stop(struct net_device *dev)
 329 {
 330         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 331         struct ieee80211_local *local = sdata->local;
 332         struct ieee80211_if_init_conf conf;
 333         struct sta_info *sta;
 334         u32 hw_reconf_flags = 0;
 335
 336         /*
 337          * Stop TX on this interface first.
 338          */
 339         netif_tx_stop_all_queues(dev);
 340
 341         /*
 342          * Now delete all active aggregation sessions.
 343          */
 344         rcu_read_lock();
 345
 346         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 347                 if (sta->sdata == sdata)
 348                         ieee80211_sta_tear_down_BA_sessions(sdata,
 349                                                             sta->sta.addr);
 350         }
 351
 352         rcu_read_unlock();
 353
 354         /*
 355          * Remove all stations associated with this interface.
 356          *
 357          * This must be done before calling ops->remove_interface()
 358          * because otherwise we can later invoke ops->sta_notify()
 359          * whenever the STAs are removed, and that invalidates driver
 360          * assumptions about always getting a vif pointer that is valid
 361          * (because if we remove a STA after ops->remove_interface()
 362          * the driver will have removed the vif info already!)
 363          *
 364          * We could relax this and only unlink the stations from the
 365          * hash table and list but keep them on a per-sdata list that
 366          * will be inserted back again when the interface is brought
 367          * up again, but I don't currently see a use case for that,
 368          * except with WDS which gets a STA entry created when it is
 369          * brought up.
 370          */
 371         sta_info_flush(local, sdata);
 372
 373         /*
 374          * Don't count this interface for promisc/allmulti while it
 375          * is down. dev_mc_unsync() will invoke set_multicast_list
 376          * on the master interface which will sync these down to the
 377          * hardware as filter flags.
 378          */
 379         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 380                 atomic_dec(&local->iff_allmultis);
 381
 382         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 383                 atomic_dec(&local->iff_promiscs);
 384
 385         dev_mc_unsync(local->mdev, dev);
 386
 387         /* APs need special treatment */
 388         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 389                 struct ieee80211_sub_if_data *vlan, *tmp;
 390                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
 391
 392                 /* remove beacon */
 393                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 394                 synchronize_rcu();
 395                 kfree(old_beacon);
 396
 397                 /* down all dependent devices, that is VLANs */
 398                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
 399                                          u.vlan.list)
 400                         dev_close(vlan->dev);
 401                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
 402         }
 403
 404         local->open_count--;
 405
 406         switch (sdata->vif.type) {
 407         case NL80211_IFTYPE_AP_VLAN:
 408                 list_del(&sdata->u.vlan.list);
 409                 /* no need to tell driver */
 410                 break;
 411         case NL80211_IFTYPE_MONITOR:
 412                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 413                         local->cooked_mntrs--;
 414                         break;
 415                 }
 416
 417                 local->monitors--;
 418                 if (local->monitors == 0) {
 419                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
 420                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
 421                 }
 422
 423                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 424                         local->fif_fcsfail--;
 425                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 426                         local->fif_plcpfail--;
 427                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 428                         local->fif_control--;
 429                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 430                         local->fif_other_bss--;
 431
 432                 netif_addr_lock_bh(local->mdev);
 433                 ieee80211_configure_filter(local);
 434                 netif_addr_unlock_bh(local->mdev);
 435                 break;
 436         case NL80211_IFTYPE_STATION:
 437         case NL80211_IFTYPE_ADHOC:
 438                 /* Announce that we are leaving the network. */
 439                 if (sdata->u.sta.state != IEEE80211_STA_MLME_DISABLED)
 440                         ieee80211_sta_deauthenticate(sdata,
 441                                                 WLAN_REASON_DEAUTH_LEAVING);
 442
 443                 memset(sdata->u.sta.bssid, 0, ETH_ALEN);
 444                 del_timer_sync(&sdata->u.sta.timer);
 445                 /*
 446                  * If the timer fired while we waited for it, it will have
 447                  * requeued the work. Now the work will be running again
 448                  * but will not rearm the timer again because it checks
 449                  * whether the interface is running, which, at this point,
 450                  * it no longer is.
 451                  */
 452                 cancel_work_sync(&sdata->u.sta.work);
 453                 /*
 454                  * When we get here, the interface is marked down.
 455                  * Call synchronize_rcu() to wait for the RX path
 456                  * should it be using the interface and enqueuing
 457                  * frames at this very time on another CPU.
 458                  */
 459                 synchronize_rcu();
 460                 skb_queue_purge(&sdata->u.sta.skb_queue);
 461
 462                 sdata->u.sta.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
 463                                         IEEE80211_STA_TKIP_WEP_USED);
 464                 kfree(sdata->u.sta.extra_ie);
 465                 sdata->u.sta.extra_ie = NULL;
 466                 sdata->u.sta.extra_ie_len = 0;
 467                 /* fall through */
 468         case NL80211_IFTYPE_MESH_POINT:
 469                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 470                         /* other_bss and allmulti are always set on mesh
 471                          * ifaces */
 472                         local->fif_other_bss--;
 473                         atomic_dec(&local->iff_allmultis);
 474
 475                         netif_addr_lock_bh(local->mdev);
 476                         ieee80211_configure_filter(local);
 477                         netif_addr_unlock_bh(local->mdev);
 478
 479                         ieee80211_stop_mesh(sdata);
 480                 }
 481                 /* fall through */
 482         default:
 483                 if (local->scan_sdata == sdata) {
 484                         if (!local->ops->hw_scan)
 485                                 cancel_delayed_work_sync(&local->scan_work);
 486                         /*
 487                          * The software scan can no longer run now, so we can
 488                          * clear out the scan_sdata reference. However, the
 489                          * hardware scan may still be running. The complete
 490                          * function must be prepared to handle a NULL value.
 491                          */
 492                         local->scan_sdata = NULL;
 493                         /*
 494                          * The memory barrier guarantees that another CPU
 495                          * that is hardware-scanning will now see the fact
 496                          * that this interface is gone.
 497                          */
 498                         smp_mb();
 499                         /*
 500                          * If software scanning, complete the scan but since
 501                          * the scan_sdata is NULL already don't send out a
 502                          * scan event to userspace -- the scan is incomplete.
 503                          */
 504                         if (local->sw_scanning)
 505                                 ieee80211_scan_completed(&local->hw);
 506                 }
 507
 508                 conf.vif = &sdata->vif;
 509                 conf.type = sdata->vif.type;
 510                 conf.mac_addr = dev->dev_addr;
 511                 /* disable all keys for as long as this netdev is down */
 512                 ieee80211_disable_keys(sdata);
 513                 local->ops->remove_interface(local_to_hw(local), &conf);
 514         }
 515
 516         sdata->bss = NULL;
 517
 518         if (local->open_count == 0) {
 519                 if (netif_running(local->mdev))
 520                         dev_close(local->mdev);
 521
 522                 if (local->ops->stop)
 523                         local->ops->stop(local_to_hw(local));
 524
 525                 ieee80211_led_radio(local, 0);
 526
 527                 flush_workqueue(local->hw.workqueue);
 528
 529                 tasklet_disable(&local->tx_pending_tasklet);
 530                 tasklet_disable(&local->tasklet);
 531
 532                 /* no reconfiguring after stop! */
 533                 hw_reconf_flags = 0;
 534         }
 535
 536         /* do after stop to avoid reconfiguring when we stop anyway */
 537         if (hw_reconf_flags)
 538                 ieee80211_hw_config(local, hw_reconf_flags);
 539
 540         return 0;
 541 }
 542
 543 static void ieee80211_set_multicast_list(struct net_device *dev)
 544 {
 545         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 546         struct ieee80211_local *local = sdata->local;
 547         int allmulti, promisc, sdata_allmulti, sdata_promisc;
 548
 549         allmulti = !!(dev->flags & IFF_ALLMULTI);
 550         promisc = !!(dev->flags & IFF_PROMISC);
 551         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
 552         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
 553
 554         if (allmulti != sdata_allmulti) {
 555                 if (dev->flags & IFF_ALLMULTI)
 556                         atomic_inc(&local->iff_allmultis);
 557                 else
 558                         atomic_dec(&local->iff_allmultis);
 559                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
 560         }
 561
 562         if (promisc != sdata_promisc) {
 563                 if (dev->flags & IFF_PROMISC)
 564                         atomic_inc(&local->iff_promiscs);
 565                 else
 566                         atomic_dec(&local->iff_promiscs);
 567                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
 568         }
 569
 570         dev_mc_sync(local->mdev, dev);
 571 }
 572
 573 static void ieee80211_if_setup(struct net_device *dev)
 574 {
 575         ether_setup(dev);
 576         dev->hard_start_xmit = ieee80211_subif_start_xmit;
 577         dev->wireless_handlers = &ieee80211_iw_handler_def;
 578         dev->set_multicast_list = ieee80211_set_multicast_list;
 579         dev->change_mtu = ieee80211_change_mtu;
 580         dev->open = ieee80211_open;
 581         dev->stop = ieee80211_stop;
 582         dev->destructor = free_netdev;
 583         /* we will validate the address ourselves in ->open */
 584         dev->validate_addr = NULL;
 585 }
 586 /*
 587  * Called when the netdev is removed or, by the code below, before
 588  * the interface type changes.
 589  */
 590 static void ieee80211_teardown_sdata(struct net_device *dev)
 591 {
 592         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 593         struct ieee80211_local *local = sdata->local;
 594         struct beacon_data *beacon;
 595         struct sk_buff *skb;
 596         int flushed;
 597         int i;
 598
 599         /* free extra data */
 600         ieee80211_free_keys(sdata);
 601
 602         ieee80211_debugfs_remove_netdev(sdata);
 603
 604         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 605                 __skb_queue_purge(&sdata->fragments[i].skb_list);
 606         sdata->fragment_next = 0;
 607
 608         switch (sdata->vif.type) {
 609         case NL80211_IFTYPE_AP:
 610                 beacon = sdata->u.ap.beacon;
 611                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 612                 synchronize_rcu();
 613                 kfree(beacon);
 614
 615                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
 616                         local->total_ps_buffered--;
 617                         dev_kfree_skb(skb);
 618                 }
 619
 620                 break;
 621         case NL80211_IFTYPE_MESH_POINT:
 622                 if (ieee80211_vif_is_mesh(&sdata->vif))
 623                         mesh_rmc_free(sdata);
 624                 break;
 625         case NL80211_IFTYPE_STATION:
 626         case NL80211_IFTYPE_ADHOC:
 627                 kfree(sdata->u.sta.extra_ie);
 628                 kfree(sdata->u.sta.assocreq_ies);
 629                 kfree(sdata->u.sta.assocresp_ies);
 630                 kfree_skb(sdata->u.sta.probe_resp);
 631                 break;
 632         case NL80211_IFTYPE_WDS:
 633         case NL80211_IFTYPE_AP_VLAN:
 634         case NL80211_IFTYPE_MONITOR:
 635                 break;
 636         case NL80211_IFTYPE_UNSPECIFIED:
 637         case __NL80211_IFTYPE_AFTER_LAST:
 638                 BUG();
 639                 break;
 640         }
 641
 642         flushed = sta_info_flush(local, sdata);
 643         WARN_ON(flushed);
 644 }
 645
 646 /*
 647  * Helper function to initialise an interface to a specific type.
 648  */
 649 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
 650                                   enum nl80211_iftype type)
 651 {
 652         /* clear type-dependent union */
 653         memset(&sdata->u, 0, sizeof(sdata->u));
 654
 655         /* and set some type-dependent values */
 656         sdata->vif.type = type;
 657         sdata->dev->hard_start_xmit = ieee80211_subif_start_xmit;
 658         sdata->wdev.iftype = type;
 659
 660         /* only monitor differs */
 661         sdata->dev->type = ARPHRD_ETHER;
 662
 663         switch (type) {
 664         case NL80211_IFTYPE_AP:
 665                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
 666                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
 667                 break;
 668         case NL80211_IFTYPE_STATION:
 669         case NL80211_IFTYPE_ADHOC:
 670                 ieee80211_sta_setup_sdata(sdata);
 671                 break;
 672         case NL80211_IFTYPE_MESH_POINT:
 673                 if (ieee80211_vif_is_mesh(&sdata->vif))
 674                         ieee80211_mesh_init_sdata(sdata);
 675                 break;
 676         case NL80211_IFTYPE_MONITOR:
 677                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 678                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
 679                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 680                                       MONITOR_FLAG_OTHER_BSS;
 681                 break;
 682         case NL80211_IFTYPE_WDS:
 683         case NL80211_IFTYPE_AP_VLAN:
 684                 break;
 685         case NL80211_IFTYPE_UNSPECIFIED:
 686         case __NL80211_IFTYPE_AFTER_LAST:
 687                 BUG();
 688                 break;
 689         }
 690
 691         ieee80211_debugfs_add_netdev(sdata);
 692 }
 693
 694 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 695                              enum nl80211_iftype type)
 696 {
 697         ASSERT_RTNL();
 698
 699         if (type == sdata->vif.type)
 700                 return 0;
 701
 702         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
 703         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
 704             type == NL80211_IFTYPE_ADHOC)
 705                 return -EOPNOTSUPP;
 706
 707         /*
 708          * We could, here, on changes between IBSS/STA/MESH modes,
 709          * invoke an MLME function instead that disassociates etc.
 710          * and goes into the requested mode.
 711          */
 712
 713         if (netif_running(sdata->dev))
 714                 return -EBUSY;
 715
 716         /* Purge and reset type-dependent state. */
 717         ieee80211_teardown_sdata(sdata->dev);
 718         ieee80211_setup_sdata(sdata, type);
 719
 720         /* reset some values that shouldn't be kept across type changes */
 721         sdata->vif.bss_conf.basic_rates =
 722                 ieee80211_mandatory_rates(sdata->local,
 723                         sdata->local->hw.conf.channel->band);
 724         sdata->drop_unencrypted = 0;
 725
 726         return 0;
 727 }
 728
 729 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 730                      struct net_device **new_dev, enum nl80211_iftype type,
 731                      struct vif_params *params)
 732 {
 733         struct net_device *ndev;
 734         struct ieee80211_sub_if_data *sdata = NULL;
 735         int ret, i;
 736
 737         ASSERT_RTNL();
 738
 739         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 740                             name, ieee80211_if_setup);
 741         if (!ndev)
 742                 return -ENOMEM;
 743
 744         ndev->needed_headroom = local->tx_headroom +
 745                                 4*6 /* four MAC addresses */
 746                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 747                                 + 6 /* mesh */
 748                                 + 8 /* rfc1042/bridge tunnel */
 749                                 - ETH_HLEN /* ethernet hard_header_len */
 750                                 + IEEE80211_ENCRYPT_HEADROOM;
 751         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 752
 753         ret = dev_alloc_name(ndev, ndev->name);
 754         if (ret < 0)
 755                 goto fail;
 756
 757         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 758         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 759
 760         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 761         sdata = netdev_priv(ndev);
 762         ndev->ieee80211_ptr = &sdata->wdev;
 763
 764         /* initialise type-independent data */
 765         sdata->wdev.wiphy = local->hw.wiphy;
 766         sdata->local = local;
 767         sdata->dev = ndev;
 768
 769         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 770                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 771
 772         INIT_LIST_HEAD(&sdata->key_list);
 773
 774         sdata->force_unicast_rateidx = -1;
 775         sdata->max_ratectrl_rateidx = -1;
 776
 777         /* setup type-dependent data */
 778         ieee80211_setup_sdata(sdata, type);
 779
 780         ret = register_netdevice(ndev);
 781         if (ret)
 782                 goto fail;
 783
 784         ndev->uninit = ieee80211_teardown_sdata;
 785
 786         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 787             params && params->mesh_id_len)
 788                 ieee80211_sdata_set_mesh_id(sdata,
 789                                             params->mesh_id_len,
 790                                             params->mesh_id);
 791
 792         list_add_tail_rcu(&sdata->list, &local->interfaces);
 793
 794         if (new_dev)
 795                 *new_dev = ndev;
 796
 797         return 0;
 798
 799  fail:
 800         free_netdev(ndev);
 801         return ret;
 802 }
 803
 804 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 805 {
 806         ASSERT_RTNL();
 807
 808         list_del_rcu(&sdata->list);
 809         synchronize_rcu();
 810         unregister_netdevice(sdata->dev);
 811 }
 812
 813 /*
 814  * Remove all interfaces, may only be called at hardware unregistration
 815  * time because it doesn't do RCU-safe list removals.
 816  */
 817 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 818 {
 819         struct ieee80211_sub_if_data *sdata, *tmp;
 820
 821         ASSERT_RTNL();
 822
 823         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 824                 list_del(&sdata->list);
 825                 unregister_netdevice(sdata->dev);
 826         }
 827 }