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         del_timer_sync(&local->dynamic_ps_timer);
 387         cancel_work_sync(&local->dynamic_ps_enable_work);
 388
 389         /* APs need special treatment */
 390         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 391                 struct ieee80211_sub_if_data *vlan, *tmp;
 392                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
 393
 394                 /* remove beacon */
 395                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 396                 synchronize_rcu();
 397                 kfree(old_beacon);
 398
 399                 /* down all dependent devices, that is VLANs */
 400                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
 401                                          u.vlan.list)
 402                         dev_close(vlan->dev);
 403                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
 404         }
 405
 406         local->open_count--;
 407
 408         switch (sdata->vif.type) {
 409         case NL80211_IFTYPE_AP_VLAN:
 410                 list_del(&sdata->u.vlan.list);
 411                 /* no need to tell driver */
 412                 break;
 413         case NL80211_IFTYPE_MONITOR:
 414                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
 415                         local->cooked_mntrs--;
 416                         break;
 417                 }
 418
 419                 local->monitors--;
 420                 if (local->monitors == 0) {
 421                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
 422                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
 423                 }
 424
 425                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
 426                         local->fif_fcsfail--;
 427                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
 428                         local->fif_plcpfail--;
 429                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
 430                         local->fif_control--;
 431                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
 432                         local->fif_other_bss--;
 433
 434                 netif_addr_lock_bh(local->mdev);
 435                 ieee80211_configure_filter(local);
 436                 netif_addr_unlock_bh(local->mdev);
 437                 break;
 438         case NL80211_IFTYPE_STATION:
 439         case NL80211_IFTYPE_ADHOC:
 440                 /* Announce that we are leaving the network. */
 441                 if (sdata->u.sta.state != IEEE80211_STA_MLME_DISABLED)
 442                         ieee80211_sta_deauthenticate(sdata,
 443                                                 WLAN_REASON_DEAUTH_LEAVING);
 444
 445                 memset(sdata->u.sta.bssid, 0, ETH_ALEN);
 446                 del_timer_sync(&sdata->u.sta.timer);
 447                 /*
 448                  * If the timer fired while we waited for it, it will have
 449                  * requeued the work. Now the work will be running again
 450                  * but will not rearm the timer again because it checks
 451                  * whether the interface is running, which, at this point,
 452                  * it no longer is.
 453                  */
 454                 cancel_work_sync(&sdata->u.sta.work);
 455                 /*
 456                  * When we get here, the interface is marked down.
 457                  * Call synchronize_rcu() to wait for the RX path
 458                  * should it be using the interface and enqueuing
 459                  * frames at this very time on another CPU.
 460                  */
 461                 synchronize_rcu();
 462                 skb_queue_purge(&sdata->u.sta.skb_queue);
 463
 464                 sdata->u.sta.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
 465                                         IEEE80211_STA_TKIP_WEP_USED);
 466                 kfree(sdata->u.sta.extra_ie);
 467                 sdata->u.sta.extra_ie = NULL;
 468                 sdata->u.sta.extra_ie_len = 0;
 469                 /* fall through */
 470         case NL80211_IFTYPE_MESH_POINT:
 471                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
 472                         /* other_bss and allmulti are always set on mesh
 473                          * ifaces */
 474                         local->fif_other_bss--;
 475                         atomic_dec(&local->iff_allmultis);
 476
 477                         netif_addr_lock_bh(local->mdev);
 478                         ieee80211_configure_filter(local);
 479                         netif_addr_unlock_bh(local->mdev);
 480
 481                         ieee80211_stop_mesh(sdata);
 482                 }
 483                 /* fall through */
 484         default:
 485                 if (local->scan_sdata == sdata) {
 486                         if (!local->ops->hw_scan)
 487                                 cancel_delayed_work_sync(&local->scan_work);
 488                         /*
 489                          * The software scan can no longer run now, so we can
 490                          * clear out the scan_sdata reference. However, the
 491                          * hardware scan may still be running. The complete
 492                          * function must be prepared to handle a NULL value.
 493                          */
 494                         local->scan_sdata = NULL;
 495                         /*
 496                          * The memory barrier guarantees that another CPU
 497                          * that is hardware-scanning will now see the fact
 498                          * that this interface is gone.
 499                          */
 500                         smp_mb();
 501                         /*
 502                          * If software scanning, complete the scan but since
 503                          * the scan_sdata is NULL already don't send out a
 504                          * scan event to userspace -- the scan is incomplete.
 505                          */
 506                         if (local->sw_scanning)
 507                                 ieee80211_scan_completed(&local->hw);
 508                 }
 509
 510                 conf.vif = &sdata->vif;
 511                 conf.type = sdata->vif.type;
 512                 conf.mac_addr = dev->dev_addr;
 513                 /* disable all keys for as long as this netdev is down */
 514                 ieee80211_disable_keys(sdata);
 515                 local->ops->remove_interface(local_to_hw(local), &conf);
 516         }
 517
 518         sdata->bss = NULL;
 519
 520         if (local->open_count == 0) {
 521                 if (netif_running(local->mdev))
 522                         dev_close(local->mdev);
 523
 524                 if (local->ops->stop)
 525                         local->ops->stop(local_to_hw(local));
 526
 527                 ieee80211_led_radio(local, 0);
 528
 529                 flush_workqueue(local->hw.workqueue);
 530
 531                 tasklet_disable(&local->tx_pending_tasklet);
 532                 tasklet_disable(&local->tasklet);
 533
 534                 /* no reconfiguring after stop! */
 535                 hw_reconf_flags = 0;
 536         }
 537
 538         /* do after stop to avoid reconfiguring when we stop anyway */
 539         if (hw_reconf_flags)
 540                 ieee80211_hw_config(local, hw_reconf_flags);
 541
 542         return 0;
 543 }
 544
 545 static void ieee80211_set_multicast_list(struct net_device *dev)
 546 {
 547         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 548         struct ieee80211_local *local = sdata->local;
 549         int allmulti, promisc, sdata_allmulti, sdata_promisc;
 550
 551         allmulti = !!(dev->flags & IFF_ALLMULTI);
 552         promisc = !!(dev->flags & IFF_PROMISC);
 553         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
 554         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
 555
 556         if (allmulti != sdata_allmulti) {
 557                 if (dev->flags & IFF_ALLMULTI)
 558                         atomic_inc(&local->iff_allmultis);
 559                 else
 560                         atomic_dec(&local->iff_allmultis);
 561                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
 562         }
 563
 564         if (promisc != sdata_promisc) {
 565                 if (dev->flags & IFF_PROMISC)
 566                         atomic_inc(&local->iff_promiscs);
 567                 else
 568                         atomic_dec(&local->iff_promiscs);
 569                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
 570         }
 571
 572         dev_mc_sync(local->mdev, dev);
 573 }
 574
 575 static void ieee80211_if_setup(struct net_device *dev)
 576 {
 577         ether_setup(dev);
 578         dev->hard_start_xmit = ieee80211_subif_start_xmit;
 579         dev->wireless_handlers = &ieee80211_iw_handler_def;
 580         dev->set_multicast_list = ieee80211_set_multicast_list;
 581         dev->change_mtu = ieee80211_change_mtu;
 582         dev->open = ieee80211_open;
 583         dev->stop = ieee80211_stop;
 584         dev->destructor = free_netdev;
 585         /* we will validate the address ourselves in ->open */
 586         dev->validate_addr = NULL;
 587 }
 588 /*
 589  * Called when the netdev is removed or, by the code below, before
 590  * the interface type changes.
 591  */
 592 static void ieee80211_teardown_sdata(struct net_device *dev)
 593 {
 594         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 595         struct ieee80211_local *local = sdata->local;
 596         struct beacon_data *beacon;
 597         struct sk_buff *skb;
 598         int flushed;
 599         int i;
 600
 601         /* free extra data */
 602         ieee80211_free_keys(sdata);
 603
 604         ieee80211_debugfs_remove_netdev(sdata);
 605
 606         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 607                 __skb_queue_purge(&sdata->fragments[i].skb_list);
 608         sdata->fragment_next = 0;
 609
 610         switch (sdata->vif.type) {
 611         case NL80211_IFTYPE_AP:
 612                 beacon = sdata->u.ap.beacon;
 613                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 614                 synchronize_rcu();
 615                 kfree(beacon);
 616
 617                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
 618                         local->total_ps_buffered--;
 619                         dev_kfree_skb(skb);
 620                 }
 621
 622                 break;
 623         case NL80211_IFTYPE_MESH_POINT:
 624                 if (ieee80211_vif_is_mesh(&sdata->vif))
 625                         mesh_rmc_free(sdata);
 626                 break;
 627         case NL80211_IFTYPE_STATION:
 628         case NL80211_IFTYPE_ADHOC:
 629                 kfree(sdata->u.sta.extra_ie);
 630                 kfree(sdata->u.sta.assocreq_ies);
 631                 kfree(sdata->u.sta.assocresp_ies);
 632                 kfree_skb(sdata->u.sta.probe_resp);
 633                 break;
 634         case NL80211_IFTYPE_WDS:
 635         case NL80211_IFTYPE_AP_VLAN:
 636         case NL80211_IFTYPE_MONITOR:
 637                 break;
 638         case NL80211_IFTYPE_UNSPECIFIED:
 639         case __NL80211_IFTYPE_AFTER_LAST:
 640                 BUG();
 641                 break;
 642         }
 643
 644         flushed = sta_info_flush(local, sdata);
 645         WARN_ON(flushed);
 646 }
 647
 648 /*
 649  * Helper function to initialise an interface to a specific type.
 650  */
 651 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
 652                                   enum nl80211_iftype type)
 653 {
 654         /* clear type-dependent union */
 655         memset(&sdata->u, 0, sizeof(sdata->u));
 656
 657         /* and set some type-dependent values */
 658         sdata->vif.type = type;
 659         sdata->dev->hard_start_xmit = ieee80211_subif_start_xmit;
 660         sdata->wdev.iftype = type;
 661
 662         /* only monitor differs */
 663         sdata->dev->type = ARPHRD_ETHER;
 664
 665         switch (type) {
 666         case NL80211_IFTYPE_AP:
 667                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
 668                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
 669                 break;
 670         case NL80211_IFTYPE_STATION:
 671         case NL80211_IFTYPE_ADHOC:
 672                 ieee80211_sta_setup_sdata(sdata);
 673                 break;
 674         case NL80211_IFTYPE_MESH_POINT:
 675                 if (ieee80211_vif_is_mesh(&sdata->vif))
 676                         ieee80211_mesh_init_sdata(sdata);
 677                 break;
 678         case NL80211_IFTYPE_MONITOR:
 679                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 680                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
 681                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 682                                       MONITOR_FLAG_OTHER_BSS;
 683                 break;
 684         case NL80211_IFTYPE_WDS:
 685         case NL80211_IFTYPE_AP_VLAN:
 686                 break;
 687         case NL80211_IFTYPE_UNSPECIFIED:
 688         case __NL80211_IFTYPE_AFTER_LAST:
 689                 BUG();
 690                 break;
 691         }
 692
 693         ieee80211_debugfs_add_netdev(sdata);
 694 }
 695
 696 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 697                              enum nl80211_iftype type)
 698 {
 699         ASSERT_RTNL();
 700
 701         if (type == sdata->vif.type)
 702                 return 0;
 703
 704         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
 705         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
 706             type == NL80211_IFTYPE_ADHOC)
 707                 return -EOPNOTSUPP;
 708
 709         /*
 710          * We could, here, on changes between IBSS/STA/MESH modes,
 711          * invoke an MLME function instead that disassociates etc.
 712          * and goes into the requested mode.
 713          */
 714
 715         if (netif_running(sdata->dev))
 716                 return -EBUSY;
 717
 718         /* Purge and reset type-dependent state. */
 719         ieee80211_teardown_sdata(sdata->dev);
 720         ieee80211_setup_sdata(sdata, type);
 721
 722         /* reset some values that shouldn't be kept across type changes */
 723         sdata->vif.bss_conf.basic_rates =
 724                 ieee80211_mandatory_rates(sdata->local,
 725                         sdata->local->hw.conf.channel->band);
 726         sdata->drop_unencrypted = 0;
 727
 728         return 0;
 729 }
 730
 731 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 732                      struct net_device **new_dev, enum nl80211_iftype type,
 733                      struct vif_params *params)
 734 {
 735         struct net_device *ndev;
 736         struct ieee80211_sub_if_data *sdata = NULL;
 737         int ret, i;
 738
 739         ASSERT_RTNL();
 740
 741         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 742                             name, ieee80211_if_setup);
 743         if (!ndev)
 744                 return -ENOMEM;
 745
 746         ndev->needed_headroom = local->tx_headroom +
 747                                 4*6 /* four MAC addresses */
 748                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 749                                 + 6 /* mesh */
 750                                 + 8 /* rfc1042/bridge tunnel */
 751                                 - ETH_HLEN /* ethernet hard_header_len */
 752                                 + IEEE80211_ENCRYPT_HEADROOM;
 753         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 754
 755         ret = dev_alloc_name(ndev, ndev->name);
 756         if (ret < 0)
 757                 goto fail;
 758
 759         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 760         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 761
 762         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 763         sdata = netdev_priv(ndev);
 764         ndev->ieee80211_ptr = &sdata->wdev;
 765
 766         /* initialise type-independent data */
 767         sdata->wdev.wiphy = local->hw.wiphy;
 768         sdata->local = local;
 769         sdata->dev = ndev;
 770
 771         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 772                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 773
 774         INIT_LIST_HEAD(&sdata->key_list);
 775
 776         sdata->force_unicast_rateidx = -1;
 777         sdata->max_ratectrl_rateidx = -1;
 778
 779         /* setup type-dependent data */
 780         ieee80211_setup_sdata(sdata, type);
 781
 782         ret = register_netdevice(ndev);
 783         if (ret)
 784                 goto fail;
 785
 786         ndev->uninit = ieee80211_teardown_sdata;
 787
 788         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 789             params && params->mesh_id_len)
 790                 ieee80211_sdata_set_mesh_id(sdata,
 791                                             params->mesh_id_len,
 792                                             params->mesh_id);
 793
 794         list_add_tail_rcu(&sdata->list, &local->interfaces);
 795
 796         if (new_dev)
 797                 *new_dev = ndev;
 798
 799         return 0;
 800
 801  fail:
 802         free_netdev(ndev);
 803         return ret;
 804 }
 805
 806 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 807 {
 808         ASSERT_RTNL();
 809
 810         list_del_rcu(&sdata->list);
 811         synchronize_rcu();
 812         unregister_netdevice(sdata->dev);
 813 }
 814
 815 /*
 816  * Remove all interfaces, may only be called at hardware unregistration
 817  * time because it doesn't do RCU-safe list removals.
 818  */
 819 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 820 {
 821         struct ieee80211_sub_if_data *sdata, *tmp;
 822
 823         ASSERT_RTNL();
 824
 825         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 826                 list_del(&sdata->list);
 827                 unregister_netdevice(sdata->dev);
 828         }
 829 }