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 /**
  25  * DOC: Interface list locking
  26  *
  27  * The interface list in each struct ieee80211_local is protected
  28  * three-fold:
  29  *
  30  * (1) modifications may only be done under the RTNL
  31  * (2) modifications and readers are protected against each other by
  32  *     the iflist_mtx.
  33  * (3) modifications are done in an RCU manner so atomic readers
  34  *     can traverse the list in RCU-safe blocks.
  35  *
  36  * As a consequence, reads (traversals) of the list can be protected
  37  * by either the RTNL, the iflist_mtx or RCU.
  38  */
  39
  40
  41 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
  42 {
  43         int meshhdrlen;
  44         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  45
  46         meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
  47
  48         /* FIX: what would be proper limits for MTU?
  49          * This interface uses 802.3 frames. */
  50         if (new_mtu < 256 ||
  51             new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
  52                 return -EINVAL;
  53         }
  54
  55 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  56         printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
  57 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
  58         dev->mtu = new_mtu;
  59         return 0;
  60 }
  61
  62 static inline int identical_mac_addr_allowed(int type1, int type2)
  63 {
  64         return type1 == NL80211_IFTYPE_MONITOR ||
  65                 type2 == NL80211_IFTYPE_MONITOR ||
  66                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
  67                 (type1 == NL80211_IFTYPE_WDS &&
  68                         (type2 == NL80211_IFTYPE_WDS ||
  69                          type2 == NL80211_IFTYPE_AP)) ||
  70                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
  71                 (type1 == NL80211_IFTYPE_AP_VLAN &&
  72                         (type2 == NL80211_IFTYPE_AP ||
  73                          type2 == NL80211_IFTYPE_AP_VLAN));
  74 }
  75
  76 static int ieee80211_open(struct net_device *dev)
  77 {
  78         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  79         struct ieee80211_sub_if_data *nsdata;
  80         struct ieee80211_local *local = sdata->local;
  81         struct sta_info *sta;
  82         struct ieee80211_if_init_conf conf;
  83         u32 changed = 0;
  84         int res;
  85         u32 hw_reconf_flags = 0;
  86         u8 null_addr[ETH_ALEN] = {0};
  87
  88         /* fail early if user set an invalid address */
  89         if (compare_ether_addr(dev->dev_addr, null_addr) &&
  90             !is_valid_ether_addr(dev->dev_addr))
  91                 return -EADDRNOTAVAIL;
  92
  93         /* we hold the RTNL here so can safely walk the list */
  94         list_for_each_entry(nsdata, &local->interfaces, list) {
  95                 struct net_device *ndev = nsdata->dev;
  96
  97                 if (ndev != dev && netif_running(ndev)) {
  98                         /*
  99                          * Allow only a single IBSS interface to be up at any
 100                          * time. This is restricted because beacon distribution
 101                          * cannot work properly if both are in the same IBSS.
 102                          *
 103                          * To remove this restriction we'd have to disallow them
 104                          * from setting the same SSID on different IBSS interfaces
 105                          * belonging to the same hardware. Then, however, we're
 106                          * faced with having to adopt two different TSF timers...
 107                          */
 108                         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 109                             nsdata->vif.type == NL80211_IFTYPE_ADHOC)
 110                                 return -EBUSY;
 111
 112                         /*
 113                          * The remaining checks are only performed for interfaces
 114                          * with the same MAC address.
 115                          */
 116                         if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
 117                                 continue;
 118
 119                         /*
 120                          * check whether it may have the same address
 121                          */
 122                         if (!identical_mac_addr_allowed(sdata->vif.type,
 123                                                         nsdata->vif.type))
 124                                 return -ENOTUNIQ;
 125
 126                         /*
 127                          * can only add VLANs to enabled APs
 128                          */
 129                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
 130                             nsdata->vif.type == NL80211_IFTYPE_AP)
 131                                 sdata->bss = &nsdata->u.ap;
 132                 }
 133         }
 134
 135         switch (sdata->vif.type) {
 136         case NL80211_IFTYPE_WDS:
 137                 if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
 138                         return -ENOLINK;
 139                 break;
 140         case NL80211_IFTYPE_AP_VLAN:
 141                 if (!sdata->bss)
 142                         return -ENOLINK;
 143                 list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
 144                 break;
 145         case NL80211_IFTYPE_AP:
 146                 sdata->bss = &sdata->u.ap;
 147                 break;
 148         case NL80211_IFTYPE_MESH_POINT:
 149                 if (!ieee80211_vif_is_mesh(&sdata->vif))
 150                         break;
 151                 /* mesh ifaces must set allmulti to forward mcast traffic */
 152                 atomic_inc(&local->iff_allmultis);
 153                 break;
 154         case NL80211_IFTYPE_STATION:
 155         case NL80211_IFTYPE_MONITOR:
 156         case NL80211_IFTYPE_ADHOC:
 157                 /* no special treatment */
 158                 break;
 159         case NL80211_IFTYPE_UNSPECIFIED:
 160         case __NL80211_IFTYPE_AFTER_LAST:
 161                 /* cannot happen */
 162                 WARN_ON(1);
 163                 break;
 164         }
 165
 166         if (local->open_count == 0) {
 167                 res = 0;
 168                 if (local->ops->start)
 169                         res = local->ops->start(local_to_hw(local));
 170                 if (res)
 171                         goto err_del_bss;
 172                 /* we're brought up, everything changes */
 173                 hw_reconf_flags = ~0;
 174                 ieee80211_led_radio(local, local->hw.conf.radio_enabled);
 175         }
 176
 177         /*
 178          * Check all interfaces and copy the hopefully now-present
 179          * MAC address to those that have the special null one.
 180          */
 181         list_for_each_entry(nsdata, &local->interfaces, list) {
 182                 struct net_device *ndev = nsdata->dev;
 183
 184                 /*
 185                  * No need to check netif_running since we do not allow
 186                  * it to start up with this invalid address.
 187                  */
 188                 if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
 189                         memcpy(ndev->dev_addr,
 190                                local->hw.wiphy->perm_addr,
 191                                ETH_ALEN);
 192         }
 193
 194         if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
 195                 memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
 196                        ETH_ALEN);
 197
 198         /*
 199          * Validate the MAC address for this device.
 200          */
 201         if (!is_valid_ether_addr(dev->dev_addr)) {
 202                 if (!local->open_count && local->ops->stop)
 203                         local->ops->stop(local_to_hw(local));
 204                 return -EADDRNOTAVAIL;
 205         }
 206
 207         switch (sdata->vif.type) {
 208         case NL80211_IFTYPE_AP_VLAN:
 209                 /* no need to tell driver */
 210                 break;
 211         case NL80211_IFTYPE_MONITOR:
 212                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 213                         local->cooked_mntrs++;
 214                         break;
 215                 }
 216
 217                 /* must be before the call to ieee80211_configure_filter */
 218                 local->monitors++;
 219                 if (local->monitors == 1) {
 220                         local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
 221                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
 222                 }
 223
 224                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 225                         local->fif_fcsfail++;
 226                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 227                         local->fif_plcpfail++;
 228                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 229                         local->fif_control++;
 230                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 231                         local->fif_other_bss++;
 232
 233                 netif_addr_lock_bh(local->mdev);
 234                 ieee80211_configure_filter(local);
 235                 netif_addr_unlock_bh(local->mdev);
 236                 break;
 237         case NL80211_IFTYPE_STATION:
 238         case NL80211_IFTYPE_ADHOC:
 239                 sdata->u.sta.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
 240                 /* fall through */
 241         default:
 242                 conf.vif = &sdata->vif;
 243                 conf.type = sdata->vif.type;
 244                 conf.mac_addr = dev->dev_addr;
 245                 res = local->ops->add_interface(local_to_hw(local), &conf);
 246                 if (res)
 247                         goto err_stop;
 248
 249                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 250                         local->fif_other_bss++;
 251                         netif_addr_lock_bh(local->mdev);
 252                         ieee80211_configure_filter(local);
 253                         netif_addr_unlock_bh(local->mdev);
 254
 255                         ieee80211_start_mesh(sdata);
 256                 }
 257                 changed |= ieee80211_reset_erp_info(sdata);
 258                 ieee80211_bss_info_change_notify(sdata, changed);
 259                 ieee80211_enable_keys(sdata);
 260
 261                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 262                     !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
 263                         netif_carrier_off(dev);
 264                 else
 265                         netif_carrier_on(dev);
 266         }
 267
 268         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
 269                 /* Create STA entry for the WDS peer */
 270                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
 271                                      GFP_KERNEL);
 272                 if (!sta) {
 273                         res = -ENOMEM;
 274                         goto err_del_interface;
 275                 }
 276
 277                 /* no locking required since STA is not live yet */
 278                 sta->flags |= WLAN_STA_AUTHORIZED;
 279
 280                 res = sta_info_insert(sta);
 281                 if (res) {
 282                         /* STA has been freed */
 283                         goto err_del_interface;
 284                 }
 285         }
 286
 287         if (local->open_count == 0) {
 288                 res = dev_open(local->mdev);
 289                 WARN_ON(res);
 290                 if (res)
 291                         goto err_del_interface;
 292                 tasklet_enable(&local->tx_pending_tasklet);
 293                 tasklet_enable(&local->tasklet);
 294         }
 295
 296         /*
 297          * set_multicast_list will be invoked by the networking core
 298          * which will check whether any increments here were done in
 299          * error and sync them down to the hardware as filter flags.
 300          */
 301         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 302                 atomic_inc(&local->iff_allmultis);
 303
 304         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 305                 atomic_inc(&local->iff_promiscs);
 306
 307         local->open_count++;
 308         if (hw_reconf_flags) {
 309                 ieee80211_hw_config(local, hw_reconf_flags);
 310                 /*
 311                  * set default queue parameters so drivers don't
 312                  * need to initialise the hardware if the hardware
 313                  * doesn't start up with sane defaults
 314                  */
 315                 ieee80211_set_wmm_default(sdata);
 316         }
 317
 318         /*
 319          * ieee80211_sta_work is disabled while network interface
 320          * is down. Therefore, some configuration changes may not
 321          * yet be effective. Trigger execution of ieee80211_sta_work
 322          * to fix this.
 323          */
 324         if (sdata->vif.type == NL80211_IFTYPE_STATION ||
 325             sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 326                 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 327                 queue_work(local->hw.workqueue, &ifsta->work);
 328         }
 329
 330         netif_tx_start_all_queues(dev);
 331
 332         return 0;
 333  err_del_interface:
 334         local->ops->remove_interface(local_to_hw(local), &conf);
 335  err_stop:
 336         if (!local->open_count && local->ops->stop)
 337                 local->ops->stop(local_to_hw(local));
 338  err_del_bss:
 339         sdata->bss = NULL;
 340         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 341                 list_del(&sdata->u.vlan.list);
 342         return res;
 343 }
 344
 345 static int ieee80211_stop(struct net_device *dev)
 346 {
 347         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 348         struct ieee80211_local *local = sdata->local;
 349         struct ieee80211_if_init_conf conf;
 350         struct sta_info *sta;
 351         u32 hw_reconf_flags = 0;
 352
 353         /*
 354          * Stop TX on this interface first.
 355          */
 356         netif_tx_stop_all_queues(dev);
 357
 358         /*
 359          * Now delete all active aggregation sessions.
 360          */
 361         rcu_read_lock();
 362
 363         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 364                 if (sta->sdata == sdata)
 365                         ieee80211_sta_tear_down_BA_sessions(sta);
 366         }
 367
 368         rcu_read_unlock();
 369
 370         /*
 371          * Remove all stations associated with this interface.
 372          *
 373          * This must be done before calling ops->remove_interface()
 374          * because otherwise we can later invoke ops->sta_notify()
 375          * whenever the STAs are removed, and that invalidates driver
 376          * assumptions about always getting a vif pointer that is valid
 377          * (because if we remove a STA after ops->remove_interface()
 378          * the driver will have removed the vif info already!)
 379          *
 380          * We could relax this and only unlink the stations from the
 381          * hash table and list but keep them on a per-sdata list that
 382          * will be inserted back again when the interface is brought
 383          * up again, but I don't currently see a use case for that,
 384          * except with WDS which gets a STA entry created when it is
 385          * brought up.
 386          */
 387         sta_info_flush(local, sdata);
 388
 389         /*
 390          * Don't count this interface for promisc/allmulti while it
 391          * is down. dev_mc_unsync() will invoke set_multicast_list
 392          * on the master interface which will sync these down to the
 393          * hardware as filter flags.
 394          */
 395         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
 396                 atomic_dec(&local->iff_allmultis);
 397
 398         if (sdata->flags & IEEE80211_SDATA_PROMISC)
 399                 atomic_dec(&local->iff_promiscs);
 400
 401         dev_mc_unsync(local->mdev, dev);
 402         del_timer_sync(&local->dynamic_ps_timer);
 403         cancel_work_sync(&local->dynamic_ps_enable_work);
 404
 405         /* APs need special treatment */
 406         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 407                 struct ieee80211_sub_if_data *vlan, *tmp;
 408                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
 409
 410                 /* remove beacon */
 411                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 412                 synchronize_rcu();
 413                 kfree(old_beacon);
 414
 415                 /* down all dependent devices, that is VLANs */
 416                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
 417                                          u.vlan.list)
 418                         dev_close(vlan->dev);
 419                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
 420         }
 421
 422         local->open_count--;
 423
 424         switch (sdata->vif.type) {
 425         case NL80211_IFTYPE_AP_VLAN:
 426                 list_del(&sdata->u.vlan.list);
 427                 /* no need to tell driver */
 428                 break;
 429         case NL80211_IFTYPE_MONITOR:
 430                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 431                         local->cooked_mntrs--;
 432                         break;
 433                 }
 434
 435                 local->monitors--;
 436                 if (local->monitors == 0) {
 437                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
 438                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
 439                 }
 440
 441                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 442                         local->fif_fcsfail--;
 443                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 444                         local->fif_plcpfail--;
 445                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 446                         local->fif_control--;
 447                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 448                         local->fif_other_bss--;
 449
 450                 netif_addr_lock_bh(local->mdev);
 451                 ieee80211_configure_filter(local);
 452                 netif_addr_unlock_bh(local->mdev);
 453                 break;
 454         case NL80211_IFTYPE_STATION:
 455         case NL80211_IFTYPE_ADHOC:
 456                 /* Announce that we are leaving the network. */
 457                 if (sdata->u.sta.state != IEEE80211_STA_MLME_DISABLED)
 458                         ieee80211_sta_deauthenticate(sdata,
 459                                                 WLAN_REASON_DEAUTH_LEAVING);
 460
 461                 memset(sdata->u.sta.bssid, 0, ETH_ALEN);
 462                 del_timer_sync(&sdata->u.sta.chswitch_timer);
 463                 del_timer_sync(&sdata->u.sta.timer);
 464                 /*
 465                  * If the timer fired while we waited for it, it will have
 466                  * requeued the work. Now the work will be running again
 467                  * but will not rearm the timer again because it checks
 468                  * whether the interface is running, which, at this point,
 469                  * it no longer is.
 470                  */
 471                 cancel_work_sync(&sdata->u.sta.work);
 472                 cancel_work_sync(&sdata->u.sta.chswitch_work);
 473                 /*
 474                  * When we get here, the interface is marked down.
 475                  * Call synchronize_rcu() to wait for the RX path
 476                  * should it be using the interface and enqueuing
 477                  * frames at this very time on another CPU.
 478                  */
 479                 synchronize_rcu();
 480                 skb_queue_purge(&sdata->u.sta.skb_queue);
 481
 482                 sdata->u.sta.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
 483                                         IEEE80211_STA_TKIP_WEP_USED);
 484                 kfree(sdata->u.sta.extra_ie);
 485                 sdata->u.sta.extra_ie = NULL;
 486                 sdata->u.sta.extra_ie_len = 0;
 487                 /* fall through */
 488         case NL80211_IFTYPE_MESH_POINT:
 489                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 490                         /* other_bss and allmulti are always set on mesh
 491                          * ifaces */
 492                         local->fif_other_bss--;
 493                         atomic_dec(&local->iff_allmultis);
 494
 495                         netif_addr_lock_bh(local->mdev);
 496                         ieee80211_configure_filter(local);
 497                         netif_addr_unlock_bh(local->mdev);
 498
 499                         ieee80211_stop_mesh(sdata);
 500                 }
 501                 /* fall through */
 502         default:
 503                 if (local->scan_sdata == sdata) {
 504                         if (!local->ops->hw_scan)
 505                                 cancel_delayed_work_sync(&local->scan_work);
 506                         /*
 507                          * The software scan can no longer run now, so we can
 508                          * clear out the scan_sdata reference. However, the
 509                          * hardware scan may still be running. The complete
 510                          * function must be prepared to handle a NULL value.
 511                          */
 512                         local->scan_sdata = NULL;
 513                         /*
 514                          * The memory barrier guarantees that another CPU
 515                          * that is hardware-scanning will now see the fact
 516                          * that this interface is gone.
 517                          */
 518                         smp_mb();
 519                         /*
 520                          * If software scanning, complete the scan but since
 521                          * the scan_sdata is NULL already don't send out a
 522                          * scan event to userspace -- the scan is incomplete.
 523                          */
 524                         if (local->sw_scanning)
 525                                 ieee80211_scan_completed(&local->hw, true);
 526                 }
 527
 528                 conf.vif = &sdata->vif;
 529                 conf.type = sdata->vif.type;
 530                 conf.mac_addr = dev->dev_addr;
 531                 /* disable all keys for as long as this netdev is down */
 532                 ieee80211_disable_keys(sdata);
 533                 local->ops->remove_interface(local_to_hw(local), &conf);
 534         }
 535
 536         sdata->bss = NULL;
 537
 538         if (local->open_count == 0) {
 539                 if (netif_running(local->mdev))
 540                         dev_close(local->mdev);
 541
 542                 if (local->ops->stop)
 543                         local->ops->stop(local_to_hw(local));
 544
 545                 ieee80211_led_radio(local, 0);
 546
 547                 flush_workqueue(local->hw.workqueue);
 548
 549                 tasklet_disable(&local->tx_pending_tasklet);
 550                 tasklet_disable(&local->tasklet);
 551
 552                 /* no reconfiguring after stop! */
 553                 hw_reconf_flags = 0;
 554         }
 555
 556         /* do after stop to avoid reconfiguring when we stop anyway */
 557         if (hw_reconf_flags)
 558                 ieee80211_hw_config(local, hw_reconf_flags);
 559
 560         return 0;
 561 }
 562
 563 static void ieee80211_set_multicast_list(struct net_device *dev)
 564 {
 565         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 566         struct ieee80211_local *local = sdata->local;
 567         int allmulti, promisc, sdata_allmulti, sdata_promisc;
 568
 569         allmulti = !!(dev->flags & IFF_ALLMULTI);
 570         promisc = !!(dev->flags & IFF_PROMISC);
 571         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
 572         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
 573
 574         if (allmulti != sdata_allmulti) {
 575                 if (dev->flags & IFF_ALLMULTI)
 576                         atomic_inc(&local->iff_allmultis);
 577                 else
 578                         atomic_dec(&local->iff_allmultis);
 579                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
 580         }
 581
 582         if (promisc != sdata_promisc) {
 583                 if (dev->flags & IFF_PROMISC)
 584                         atomic_inc(&local->iff_promiscs);
 585                 else
 586                         atomic_dec(&local->iff_promiscs);
 587                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
 588         }
 589
 590         dev_mc_sync(local->mdev, dev);
 591 }
 592
 593 /*
 594  * Called when the netdev is removed or, by the code below, before
 595  * the interface type changes.
 596  */
 597 static void ieee80211_teardown_sdata(struct net_device *dev)
 598 {
 599         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 600         struct ieee80211_local *local = sdata->local;
 601         struct beacon_data *beacon;
 602         struct sk_buff *skb;
 603         int flushed;
 604         int i;
 605
 606         /* free extra data */
 607         ieee80211_free_keys(sdata);
 608
 609         ieee80211_debugfs_remove_netdev(sdata);
 610
 611         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 612                 __skb_queue_purge(&sdata->fragments[i].skb_list);
 613         sdata->fragment_next = 0;
 614
 615         switch (sdata->vif.type) {
 616         case NL80211_IFTYPE_AP:
 617                 beacon = sdata->u.ap.beacon;
 618                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 619                 synchronize_rcu();
 620                 kfree(beacon);
 621
 622                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
 623                         local->total_ps_buffered--;
 624                         dev_kfree_skb(skb);
 625                 }
 626
 627                 break;
 628         case NL80211_IFTYPE_MESH_POINT:
 629                 if (ieee80211_vif_is_mesh(&sdata->vif))
 630                         mesh_rmc_free(sdata);
 631                 break;
 632         case NL80211_IFTYPE_STATION:
 633         case NL80211_IFTYPE_ADHOC:
 634                 kfree(sdata->u.sta.extra_ie);
 635                 kfree(sdata->u.sta.assocreq_ies);
 636                 kfree(sdata->u.sta.assocresp_ies);
 637                 kfree_skb(sdata->u.sta.probe_resp);
 638                 kfree(sdata->u.sta.ie_probereq);
 639                 kfree(sdata->u.sta.ie_proberesp);
 640                 kfree(sdata->u.sta.ie_auth);
 641                 kfree(sdata->u.sta.ie_assocreq);
 642                 kfree(sdata->u.sta.ie_reassocreq);
 643                 kfree(sdata->u.sta.ie_deauth);
 644                 kfree(sdata->u.sta.ie_disassoc);
 645                 break;
 646         case NL80211_IFTYPE_WDS:
 647         case NL80211_IFTYPE_AP_VLAN:
 648         case NL80211_IFTYPE_MONITOR:
 649                 break;
 650         case NL80211_IFTYPE_UNSPECIFIED:
 651         case __NL80211_IFTYPE_AFTER_LAST:
 652                 BUG();
 653                 break;
 654         }
 655
 656         flushed = sta_info_flush(local, sdata);
 657         WARN_ON(flushed);
 658 }
 659
 660 static const struct net_device_ops ieee80211_dataif_ops = {
 661         .ndo_open               = ieee80211_open,
 662         .ndo_stop               = ieee80211_stop,
 663         .ndo_uninit             = ieee80211_teardown_sdata,
 664         .ndo_start_xmit         = ieee80211_subif_start_xmit,
 665         .ndo_set_multicast_list = ieee80211_set_multicast_list,
 666         .ndo_change_mtu         = ieee80211_change_mtu,
 667         .ndo_set_mac_address    = eth_mac_addr,
 668 };
 669
 670 static const struct net_device_ops ieee80211_monitorif_ops = {
 671         .ndo_open               = ieee80211_open,
 672         .ndo_stop               = ieee80211_stop,
 673         .ndo_uninit             = ieee80211_teardown_sdata,
 674         .ndo_start_xmit         = ieee80211_monitor_start_xmit,
 675         .ndo_set_multicast_list = ieee80211_set_multicast_list,
 676         .ndo_change_mtu         = ieee80211_change_mtu,
 677         .ndo_set_mac_address    = eth_mac_addr,
 678 };
 679
 680 static void ieee80211_if_setup(struct net_device *dev)
 681 {
 682         ether_setup(dev);
 683         dev->netdev_ops = &ieee80211_dataif_ops;
 684         dev->wireless_handlers = &ieee80211_iw_handler_def;
 685         dev->destructor = free_netdev;
 686 }
 687
 688 /*
 689  * Helper function to initialise an interface to a specific type.
 690  */
 691 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
 692                                   enum nl80211_iftype type)
 693 {
 694         /* clear type-dependent union */
 695         memset(&sdata->u, 0, sizeof(sdata->u));
 696
 697         /* and set some type-dependent values */
 698         sdata->vif.type = type;
 699         sdata->dev->netdev_ops = &ieee80211_dataif_ops;
 700         sdata->wdev.iftype = type;
 701
 702         /* only monitor differs */
 703         sdata->dev->type = ARPHRD_ETHER;
 704
 705         switch (type) {
 706         case NL80211_IFTYPE_AP:
 707                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
 708                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
 709                 break;
 710         case NL80211_IFTYPE_STATION:
 711         case NL80211_IFTYPE_ADHOC:
 712                 ieee80211_sta_setup_sdata(sdata);
 713                 break;
 714         case NL80211_IFTYPE_MESH_POINT:
 715                 if (ieee80211_vif_is_mesh(&sdata->vif))
 716                         ieee80211_mesh_init_sdata(sdata);
 717                 break;
 718         case NL80211_IFTYPE_MONITOR:
 719                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 720                 sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
 721                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 722                                       MONITOR_FLAG_OTHER_BSS;
 723                 break;
 724         case NL80211_IFTYPE_WDS:
 725         case NL80211_IFTYPE_AP_VLAN:
 726                 break;
 727         case NL80211_IFTYPE_UNSPECIFIED:
 728         case __NL80211_IFTYPE_AFTER_LAST:
 729                 BUG();
 730                 break;
 731         }
 732
 733         ieee80211_debugfs_add_netdev(sdata);
 734 }
 735
 736 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 737                              enum nl80211_iftype type)
 738 {
 739         ASSERT_RTNL();
 740
 741         if (type == sdata->vif.type)
 742                 return 0;
 743
 744         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
 745         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
 746             type == NL80211_IFTYPE_ADHOC)
 747                 return -EOPNOTSUPP;
 748
 749         /*
 750          * We could, here, on changes between IBSS/STA/MESH modes,
 751          * invoke an MLME function instead that disassociates etc.
 752          * and goes into the requested mode.
 753          */
 754
 755         if (netif_running(sdata->dev))
 756                 return -EBUSY;
 757
 758         /* Purge and reset type-dependent state. */
 759         ieee80211_teardown_sdata(sdata->dev);
 760         ieee80211_setup_sdata(sdata, type);
 761
 762         /* reset some values that shouldn't be kept across type changes */
 763         sdata->vif.bss_conf.basic_rates =
 764                 ieee80211_mandatory_rates(sdata->local,
 765                         sdata->local->hw.conf.channel->band);
 766         sdata->drop_unencrypted = 0;
 767
 768         return 0;
 769 }
 770
 771 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 772                      struct net_device **new_dev, enum nl80211_iftype type,
 773                      struct vif_params *params)
 774 {
 775         struct net_device *ndev;
 776         struct ieee80211_sub_if_data *sdata = NULL;
 777         int ret, i;
 778
 779         ASSERT_RTNL();
 780
 781         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 782                             name, ieee80211_if_setup);
 783         if (!ndev)
 784                 return -ENOMEM;
 785
 786         ndev->needed_headroom = local->tx_headroom +
 787                                 4*6 /* four MAC addresses */
 788                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 789                                 + 6 /* mesh */
 790                                 + 8 /* rfc1042/bridge tunnel */
 791                                 - ETH_HLEN /* ethernet hard_header_len */
 792                                 + IEEE80211_ENCRYPT_HEADROOM;
 793         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 794
 795         ret = dev_alloc_name(ndev, ndev->name);
 796         if (ret < 0)
 797                 goto fail;
 798
 799         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 800         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 801         ndev->features |= NETIF_F_NETNS_LOCAL;
 802
 803         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 804         sdata = netdev_priv(ndev);
 805         ndev->ieee80211_ptr = &sdata->wdev;
 806
 807         /* initialise type-independent data */
 808         sdata->wdev.wiphy = local->hw.wiphy;
 809         sdata->local = local;
 810         sdata->dev = ndev;
 811
 812         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 813                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 814
 815         INIT_LIST_HEAD(&sdata->key_list);
 816
 817         sdata->force_unicast_rateidx = -1;
 818         sdata->max_ratectrl_rateidx = -1;
 819
 820         /* setup type-dependent data */
 821         ieee80211_setup_sdata(sdata, type);
 822
 823         ret = register_netdevice(ndev);
 824         if (ret)
 825                 goto fail;
 826
 827         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 828             params && params->mesh_id_len)
 829                 ieee80211_sdata_set_mesh_id(sdata,
 830                                             params->mesh_id_len,
 831                                             params->mesh_id);
 832
 833         mutex_lock(&local->iflist_mtx);
 834         list_add_tail_rcu(&sdata->list, &local->interfaces);
 835         mutex_unlock(&local->iflist_mtx);
 836
 837         if (new_dev)
 838                 *new_dev = ndev;
 839
 840         return 0;
 841
 842  fail:
 843         free_netdev(ndev);
 844         return ret;
 845 }
 846
 847 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 848 {
 849         ASSERT_RTNL();
 850
 851         mutex_lock(&sdata->local->iflist_mtx);
 852         list_del_rcu(&sdata->list);
 853         mutex_unlock(&sdata->local->iflist_mtx);
 854
 855         synchronize_rcu();
 856         unregister_netdevice(sdata->dev);
 857 }
 858
 859 /*
 860  * Remove all interfaces, may only be called at hardware unregistration
 861  * time because it doesn't do RCU-safe list removals.
 862  */
 863 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 864 {
 865         struct ieee80211_sub_if_data *sdata, *tmp;
 866
 867         ASSERT_RTNL();
 868
 869         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 870                 /*
 871                  * we cannot hold the iflist_mtx across unregister_netdevice,
 872                  * but we only need to hold it for list modifications to lock
 873                  * out readers since we're under the RTNL here as all other
 874                  * writers.
 875                  */
 876                 mutex_lock(&local->iflist_mtx);
 877                 list_del(&sdata->list);
 878                 mutex_unlock(&local->iflist_mtx);
 879
 880                 unregister_netdevice(sdata->dev);
 881         }
 882 }