cfg80211: handle SIOCGIWMODE/SIOCSIWMODE
[linux-2.6.git] / 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                 kfree(sdata->u.sta.extra_ie);
464                 sdata->u.sta.extra_ie = NULL;
465                 sdata->u.sta.extra_ie_len = 0;
466                 /* fall through */
467         case NL80211_IFTYPE_MESH_POINT:
468                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
469                         /* other_bss and allmulti are always set on mesh
470                          * ifaces */
471                         local->fif_other_bss--;
472                         atomic_dec(&local->iff_allmultis);
473
474                         netif_addr_lock_bh(local->mdev);
475                         ieee80211_configure_filter(local);
476                         netif_addr_unlock_bh(local->mdev);
477
478                         ieee80211_stop_mesh(sdata);
479                 }
480                 /* fall through */
481         default:
482                 if (local->scan_sdata == sdata) {
483                         if (!local->ops->hw_scan)
484                                 cancel_delayed_work_sync(&local->scan_work);
485                         /*
486                          * The software scan can no longer run now, so we can
487                          * clear out the scan_sdata reference. However, the
488                          * hardware scan may still be running. The complete
489                          * function must be prepared to handle a NULL value.
490                          */
491                         local->scan_sdata = NULL;
492                         /*
493                          * The memory barrier guarantees that another CPU
494                          * that is hardware-scanning will now see the fact
495                          * that this interface is gone.
496                          */
497                         smp_mb();
498                         /*
499                          * If software scanning, complete the scan but since
500                          * the scan_sdata is NULL already don't send out a
501                          * scan event to userspace -- the scan is incomplete.
502                          */
503                         if (local->sw_scanning)
504                                 ieee80211_scan_completed(&local->hw);
505                 }
506
507                 conf.vif = &sdata->vif;
508                 conf.type = sdata->vif.type;
509                 conf.mac_addr = dev->dev_addr;
510                 /* disable all keys for as long as this netdev is down */
511                 ieee80211_disable_keys(sdata);
512                 local->ops->remove_interface(local_to_hw(local), &conf);
513         }
514
515         sdata->bss = NULL;
516
517         if (local->open_count == 0) {
518                 if (netif_running(local->mdev))
519                         dev_close(local->mdev);
520
521                 if (local->ops->stop)
522                         local->ops->stop(local_to_hw(local));
523
524                 ieee80211_led_radio(local, 0);
525
526                 flush_workqueue(local->hw.workqueue);
527
528                 tasklet_disable(&local->tx_pending_tasklet);
529                 tasklet_disable(&local->tasklet);
530
531                 /* no reconfiguring after stop! */
532                 hw_reconf_flags = 0;
533         }
534
535         /* do after stop to avoid reconfiguring when we stop anyway */
536         if (hw_reconf_flags)
537                 ieee80211_hw_config(local, hw_reconf_flags);
538
539         return 0;
540 }
541
542 static void ieee80211_set_multicast_list(struct net_device *dev)
543 {
544         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
545         struct ieee80211_local *local = sdata->local;
546         int allmulti, promisc, sdata_allmulti, sdata_promisc;
547
548         allmulti = !!(dev->flags & IFF_ALLMULTI);
549         promisc = !!(dev->flags & IFF_PROMISC);
550         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
551         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
552
553         if (allmulti != sdata_allmulti) {
554                 if (dev->flags & IFF_ALLMULTI)
555                         atomic_inc(&local->iff_allmultis);
556                 else
557                         atomic_dec(&local->iff_allmultis);
558                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
559         }
560
561         if (promisc != sdata_promisc) {
562                 if (dev->flags & IFF_PROMISC)
563                         atomic_inc(&local->iff_promiscs);
564                 else
565                         atomic_dec(&local->iff_promiscs);
566                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
567         }
568
569         dev_mc_sync(local->mdev, dev);
570 }
571
572 static void ieee80211_if_setup(struct net_device *dev)
573 {
574         ether_setup(dev);
575         dev->hard_start_xmit = ieee80211_subif_start_xmit;
576         dev->wireless_handlers = &ieee80211_iw_handler_def;
577         dev->set_multicast_list = ieee80211_set_multicast_list;
578         dev->change_mtu = ieee80211_change_mtu;
579         dev->open = ieee80211_open;
580         dev->stop = ieee80211_stop;
581         dev->destructor = free_netdev;
582         /* we will validate the address ourselves in ->open */
583         dev->validate_addr = NULL;
584 }
585 /*
586  * Called when the netdev is removed or, by the code below, before
587  * the interface type changes.
588  */
589 static void ieee80211_teardown_sdata(struct net_device *dev)
590 {
591         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
592         struct ieee80211_local *local = sdata->local;
593         struct beacon_data *beacon;
594         struct sk_buff *skb;
595         int flushed;
596         int i;
597
598         /* free extra data */
599         ieee80211_free_keys(sdata);
600
601         ieee80211_debugfs_remove_netdev(sdata);
602
603         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
604                 __skb_queue_purge(&sdata->fragments[i].skb_list);
605         sdata->fragment_next = 0;
606
607         switch (sdata->vif.type) {
608         case NL80211_IFTYPE_AP:
609                 beacon = sdata->u.ap.beacon;
610                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
611                 synchronize_rcu();
612                 kfree(beacon);
613
614                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
615                         local->total_ps_buffered--;
616                         dev_kfree_skb(skb);
617                 }
618
619                 break;
620         case NL80211_IFTYPE_MESH_POINT:
621                 if (ieee80211_vif_is_mesh(&sdata->vif))
622                         mesh_rmc_free(sdata);
623                 break;
624         case NL80211_IFTYPE_STATION:
625         case NL80211_IFTYPE_ADHOC:
626                 kfree(sdata->u.sta.extra_ie);
627                 kfree(sdata->u.sta.assocreq_ies);
628                 kfree(sdata->u.sta.assocresp_ies);
629                 kfree_skb(sdata->u.sta.probe_resp);
630                 break;
631         case NL80211_IFTYPE_WDS:
632         case NL80211_IFTYPE_AP_VLAN:
633         case NL80211_IFTYPE_MONITOR:
634                 break;
635         case NL80211_IFTYPE_UNSPECIFIED:
636         case __NL80211_IFTYPE_AFTER_LAST:
637                 BUG();
638                 break;
639         }
640
641         flushed = sta_info_flush(local, sdata);
642         WARN_ON(flushed);
643 }
644
645 /*
646  * Helper function to initialise an interface to a specific type.
647  */
648 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
649                                   enum nl80211_iftype type)
650 {
651         /* clear type-dependent union */
652         memset(&sdata->u, 0, sizeof(sdata->u));
653
654         /* and set some type-dependent values */
655         sdata->vif.type = type;
656         sdata->dev->hard_start_xmit = ieee80211_subif_start_xmit;
657         sdata->wdev.iftype = type;
658
659         /* only monitor differs */
660         sdata->dev->type = ARPHRD_ETHER;
661
662         switch (type) {
663         case NL80211_IFTYPE_AP:
664                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
665                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
666                 break;
667         case NL80211_IFTYPE_STATION:
668         case NL80211_IFTYPE_ADHOC:
669                 ieee80211_sta_setup_sdata(sdata);
670                 break;
671         case NL80211_IFTYPE_MESH_POINT:
672                 if (ieee80211_vif_is_mesh(&sdata->vif))
673                         ieee80211_mesh_init_sdata(sdata);
674                 break;
675         case NL80211_IFTYPE_MONITOR:
676                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
677                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
678                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
679                                       MONITOR_FLAG_OTHER_BSS;
680                 break;
681         case NL80211_IFTYPE_WDS:
682         case NL80211_IFTYPE_AP_VLAN:
683                 break;
684         case NL80211_IFTYPE_UNSPECIFIED:
685         case __NL80211_IFTYPE_AFTER_LAST:
686                 BUG();
687                 break;
688         }
689
690         ieee80211_debugfs_add_netdev(sdata);
691 }
692
693 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
694                              enum nl80211_iftype type)
695 {
696         ASSERT_RTNL();
697
698         if (type == sdata->vif.type)
699                 return 0;
700
701         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
702         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)
703                 return -EOPNOTSUPP;
704
705         /*
706          * We could, here, on changes between IBSS/STA/MESH modes,
707          * invoke an MLME function instead that disassociates etc.
708          * and goes into the requested mode.
709          */
710
711         if (netif_running(sdata->dev))
712                 return -EBUSY;
713
714         /* Purge and reset type-dependent state. */
715         ieee80211_teardown_sdata(sdata->dev);
716         ieee80211_setup_sdata(sdata, type);
717
718         /* reset some values that shouldn't be kept across type changes */
719         sdata->vif.bss_conf.basic_rates =
720                 ieee80211_mandatory_rates(sdata->local,
721                         sdata->local->hw.conf.channel->band);
722         sdata->drop_unencrypted = 0;
723
724         return 0;
725 }
726
727 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
728                      struct net_device **new_dev, enum nl80211_iftype type,
729                      struct vif_params *params)
730 {
731         struct net_device *ndev;
732         struct ieee80211_sub_if_data *sdata = NULL;
733         int ret, i;
734
735         ASSERT_RTNL();
736
737         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
738                             name, ieee80211_if_setup);
739         if (!ndev)
740                 return -ENOMEM;
741
742         ndev->needed_headroom = local->tx_headroom +
743                                 4*6 /* four MAC addresses */
744                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
745                                 + 6 /* mesh */
746                                 + 8 /* rfc1042/bridge tunnel */
747                                 - ETH_HLEN /* ethernet hard_header_len */
748                                 + IEEE80211_ENCRYPT_HEADROOM;
749         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
750
751         ret = dev_alloc_name(ndev, ndev->name);
752         if (ret < 0)
753                 goto fail;
754
755         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
756         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
757
758         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
759         sdata = netdev_priv(ndev);
760         ndev->ieee80211_ptr = &sdata->wdev;
761
762         /* initialise type-independent data */
763         sdata->wdev.wiphy = local->hw.wiphy;
764         sdata->local = local;
765         sdata->dev = ndev;
766
767         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
768                 skb_queue_head_init(&sdata->fragments[i].skb_list);
769
770         INIT_LIST_HEAD(&sdata->key_list);
771
772         sdata->force_unicast_rateidx = -1;
773         sdata->max_ratectrl_rateidx = -1;
774
775         /* setup type-dependent data */
776         ieee80211_setup_sdata(sdata, type);
777
778         ret = register_netdevice(ndev);
779         if (ret)
780                 goto fail;
781
782         ndev->uninit = ieee80211_teardown_sdata;
783
784         if (ieee80211_vif_is_mesh(&sdata->vif) &&
785             params && params->mesh_id_len)
786                 ieee80211_sdata_set_mesh_id(sdata,
787                                             params->mesh_id_len,
788                                             params->mesh_id);
789
790         list_add_tail_rcu(&sdata->list, &local->interfaces);
791
792         if (new_dev)
793                 *new_dev = ndev;
794
795         return 0;
796
797  fail:
798         free_netdev(ndev);
799         return ret;
800 }
801
802 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
803 {
804         ASSERT_RTNL();
805
806         list_del_rcu(&sdata->list);
807         synchronize_rcu();
808         unregister_netdevice(sdata->dev);
809 }
810
811 /*
812  * Remove all interfaces, may only be called at hardware unregistration
813  * time because it doesn't do RCU-safe list removals.
814  */
815 void ieee80211_remove_interfaces(struct ieee80211_local *local)
816 {
817         struct ieee80211_sub_if_data *sdata, *tmp;
818
819         ASSERT_RTNL();
820
821         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
822                 list_del(&sdata->list);
823                 unregister_netdevice(sdata->dev);
824         }
825 }