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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                 if (sdata->vif.type == NL80211_IFTYPE_STATION)
240                         sdata->u.mgd.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
241                 else
242                         sdata->u.ibss.flags &= ~IEEE80211_IBSS_PREV_BSSID_SET;
243                 /* fall through */
244         default:
245                 conf.vif = &sdata->vif;
246                 conf.type = sdata->vif.type;
247                 conf.mac_addr = dev->dev_addr;
248                 res = local->ops->add_interface(local_to_hw(local), &conf);
249                 if (res)
250                         goto err_stop;
251
252                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
253                         local->fif_other_bss++;
254                         netif_addr_lock_bh(local->mdev);
255                         ieee80211_configure_filter(local);
256                         netif_addr_unlock_bh(local->mdev);
257
258                         ieee80211_start_mesh(sdata);
259                 }
260                 changed |= ieee80211_reset_erp_info(sdata);
261                 ieee80211_bss_info_change_notify(sdata, changed);
262                 ieee80211_enable_keys(sdata);
263
264                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
265                     !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
266                         netif_carrier_off(dev);
267                 else
268                         netif_carrier_on(dev);
269         }
270
271         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
272                 /* Create STA entry for the WDS peer */
273                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
274                                      GFP_KERNEL);
275                 if (!sta) {
276                         res = -ENOMEM;
277                         goto err_del_interface;
278                 }
279
280                 /* no locking required since STA is not live yet */
281                 sta->flags |= WLAN_STA_AUTHORIZED;
282
283                 res = sta_info_insert(sta);
284                 if (res) {
285                         /* STA has been freed */
286                         goto err_del_interface;
287                 }
288         }
289
290         if (local->open_count == 0) {
291                 res = dev_open(local->mdev);
292                 WARN_ON(res);
293                 if (res)
294                         goto err_del_interface;
295                 tasklet_enable(&local->tx_pending_tasklet);
296                 tasklet_enable(&local->tasklet);
297         }
298
299         /*
300          * set_multicast_list will be invoked by the networking core
301          * which will check whether any increments here were done in
302          * error and sync them down to the hardware as filter flags.
303          */
304         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
305                 atomic_inc(&local->iff_allmultis);
306
307         if (sdata->flags & IEEE80211_SDATA_PROMISC)
308                 atomic_inc(&local->iff_promiscs);
309
310         local->open_count++;
311         if (hw_reconf_flags) {
312                 ieee80211_hw_config(local, hw_reconf_flags);
313                 /*
314                  * set default queue parameters so drivers don't
315                  * need to initialise the hardware if the hardware
316                  * doesn't start up with sane defaults
317                  */
318                 ieee80211_set_wmm_default(sdata);
319         }
320
321         /*
322          * ieee80211_sta_work is disabled while network interface
323          * is down. Therefore, some configuration changes may not
324          * yet be effective. Trigger execution of ieee80211_sta_work
325          * to fix this.
326          */
327         if (sdata->vif.type == NL80211_IFTYPE_STATION)
328                 queue_work(local->hw.workqueue, &sdata->u.mgd.work);
329         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
330                 queue_work(local->hw.workqueue, &sdata->u.ibss.work);
331
332         netif_tx_start_all_queues(dev);
333
334         return 0;
335  err_del_interface:
336         local->ops->remove_interface(local_to_hw(local), &conf);
337  err_stop:
338         if (!local->open_count && local->ops->stop)
339                 local->ops->stop(local_to_hw(local));
340  err_del_bss:
341         sdata->bss = NULL;
342         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
343                 list_del(&sdata->u.vlan.list);
344         return res;
345 }
346
347 static int ieee80211_stop(struct net_device *dev)
348 {
349         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
350         struct ieee80211_local *local = sdata->local;
351         struct ieee80211_if_init_conf conf;
352         struct sta_info *sta;
353         u32 hw_reconf_flags = 0;
354
355         /*
356          * Stop TX on this interface first.
357          */
358         netif_tx_stop_all_queues(dev);
359
360         /*
361          * Now delete all active aggregation sessions.
362          */
363         rcu_read_lock();
364
365         list_for_each_entry_rcu(sta, &local->sta_list, list) {
366                 if (sta->sdata == sdata)
367                         ieee80211_sta_tear_down_BA_sessions(sta);
368         }
369
370         rcu_read_unlock();
371
372         /*
373          * Announce that we are leaving the network, in case we are a
374          * station interface type. This must be done before removing
375          * all stations associated with sta_info_flush, otherwise STA
376          * information will be gone and no announce being done.
377          */
378         if (sdata->vif.type == NL80211_IFTYPE_STATION) {
379                 if (sdata->u.mgd.state != IEEE80211_STA_MLME_DISABLED)
380                         ieee80211_sta_deauthenticate(sdata,
381                                 WLAN_REASON_DEAUTH_LEAVING);
382         }
383
384         /*
385          * Remove all stations associated with this interface.
386          *
387          * This must be done before calling ops->remove_interface()
388          * because otherwise we can later invoke ops->sta_notify()
389          * whenever the STAs are removed, and that invalidates driver
390          * assumptions about always getting a vif pointer that is valid
391          * (because if we remove a STA after ops->remove_interface()
392          * the driver will have removed the vif info already!)
393          *
394          * We could relax this and only unlink the stations from the
395          * hash table and list but keep them on a per-sdata list that
396          * will be inserted back again when the interface is brought
397          * up again, but I don't currently see a use case for that,
398          * except with WDS which gets a STA entry created when it is
399          * brought up.
400          */
401         sta_info_flush(local, sdata);
402
403         /*
404          * Don't count this interface for promisc/allmulti while it
405          * is down. dev_mc_unsync() will invoke set_multicast_list
406          * on the master interface which will sync these down to the
407          * hardware as filter flags.
408          */
409         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
410                 atomic_dec(&local->iff_allmultis);
411
412         if (sdata->flags & IEEE80211_SDATA_PROMISC)
413                 atomic_dec(&local->iff_promiscs);
414
415         dev_mc_unsync(local->mdev, dev);
416         del_timer_sync(&local->dynamic_ps_timer);
417         cancel_work_sync(&local->dynamic_ps_enable_work);
418
419         /* APs need special treatment */
420         if (sdata->vif.type == NL80211_IFTYPE_AP) {
421                 struct ieee80211_sub_if_data *vlan, *tmp;
422                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
423
424                 /* remove beacon */
425                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
426                 synchronize_rcu();
427                 kfree(old_beacon);
428
429                 /* down all dependent devices, that is VLANs */
430                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
431                                          u.vlan.list)
432                         dev_close(vlan->dev);
433                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
434         }
435
436         local->open_count--;
437
438         switch (sdata->vif.type) {
439         case NL80211_IFTYPE_AP_VLAN:
440                 list_del(&sdata->u.vlan.list);
441                 /* no need to tell driver */
442                 break;
443         case NL80211_IFTYPE_MONITOR:
444                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
445                         local->cooked_mntrs--;
446                         break;
447                 }
448
449                 local->monitors--;
450                 if (local->monitors == 0) {
451                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
452                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
453                 }
454
455                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
456                         local->fif_fcsfail--;
457                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
458                         local->fif_plcpfail--;
459                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
460                         local->fif_control--;
461                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
462                         local->fif_other_bss--;
463
464                 netif_addr_lock_bh(local->mdev);
465                 ieee80211_configure_filter(local);
466                 netif_addr_unlock_bh(local->mdev);
467                 break;
468         case NL80211_IFTYPE_STATION:
469                 memset(sdata->u.mgd.bssid, 0, ETH_ALEN);
470                 del_timer_sync(&sdata->u.mgd.chswitch_timer);
471                 del_timer_sync(&sdata->u.mgd.timer);
472                 /*
473                  * If the timer fired while we waited for it, it will have
474                  * requeued the work. Now the work will be running again
475                  * but will not rearm the timer again because it checks
476                  * whether the interface is running, which, at this point,
477                  * it no longer is.
478                  */
479                 cancel_work_sync(&sdata->u.mgd.work);
480                 cancel_work_sync(&sdata->u.mgd.chswitch_work);
481                 /*
482                  * When we get here, the interface is marked down.
483                  * Call synchronize_rcu() to wait for the RX path
484                  * should it be using the interface and enqueuing
485                  * frames at this very time on another CPU.
486                  */
487                 synchronize_rcu();
488                 skb_queue_purge(&sdata->u.mgd.skb_queue);
489
490                 sdata->u.mgd.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
491                                         IEEE80211_STA_TKIP_WEP_USED);
492                 kfree(sdata->u.mgd.extra_ie);
493                 sdata->u.mgd.extra_ie = NULL;
494                 sdata->u.mgd.extra_ie_len = 0;
495                 /* fall through */
496         case NL80211_IFTYPE_ADHOC:
497                 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
498                         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
499                         del_timer_sync(&sdata->u.ibss.timer);
500                         cancel_work_sync(&sdata->u.ibss.work);
501                         synchronize_rcu();
502                         skb_queue_purge(&sdata->u.ibss.skb_queue);
503                 }
504                 /* fall through */
505         case NL80211_IFTYPE_MESH_POINT:
506                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
507                         /* other_bss and allmulti are always set on mesh
508                          * ifaces */
509                         local->fif_other_bss--;
510                         atomic_dec(&local->iff_allmultis);
511
512                         netif_addr_lock_bh(local->mdev);
513                         ieee80211_configure_filter(local);
514                         netif_addr_unlock_bh(local->mdev);
515
516                         ieee80211_stop_mesh(sdata);
517                 }
518                 /* fall through */
519         default:
520                 if (local->scan_sdata == sdata) {
521                         if (!local->ops->hw_scan)
522                                 cancel_delayed_work_sync(&local->scan_work);
523                         /*
524                          * The software scan can no longer run now, so we can
525                          * clear out the scan_sdata reference. However, the
526                          * hardware scan may still be running. The complete
527                          * function must be prepared to handle a NULL value.
528                          */
529                         local->scan_sdata = NULL;
530                         /*
531                          * The memory barrier guarantees that another CPU
532                          * that is hardware-scanning will now see the fact
533                          * that this interface is gone.
534                          */
535                         smp_mb();
536                         /*
537                          * If software scanning, complete the scan but since
538                          * the scan_sdata is NULL already don't send out a
539                          * scan event to userspace -- the scan is incomplete.
540                          */
541                         if (local->sw_scanning)
542                                 ieee80211_scan_completed(&local->hw, true);
543                 }
544
545                 conf.vif = &sdata->vif;
546                 conf.type = sdata->vif.type;
547                 conf.mac_addr = dev->dev_addr;
548                 /* disable all keys for as long as this netdev is down */
549                 ieee80211_disable_keys(sdata);
550                 local->ops->remove_interface(local_to_hw(local), &conf);
551         }
552
553         sdata->bss = NULL;
554
555         if (local->open_count == 0) {
556                 if (netif_running(local->mdev))
557                         dev_close(local->mdev);
558
559                 if (local->ops->stop)
560                         local->ops->stop(local_to_hw(local));
561
562                 ieee80211_led_radio(local, 0);
563
564                 flush_workqueue(local->hw.workqueue);
565
566                 tasklet_disable(&local->tx_pending_tasklet);
567                 tasklet_disable(&local->tasklet);
568
569                 /* no reconfiguring after stop! */
570                 hw_reconf_flags = 0;
571         }
572
573         /* do after stop to avoid reconfiguring when we stop anyway */
574         if (hw_reconf_flags)
575                 ieee80211_hw_config(local, hw_reconf_flags);
576
577         return 0;
578 }
579
580 static void ieee80211_set_multicast_list(struct net_device *dev)
581 {
582         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
583         struct ieee80211_local *local = sdata->local;
584         int allmulti, promisc, sdata_allmulti, sdata_promisc;
585
586         allmulti = !!(dev->flags & IFF_ALLMULTI);
587         promisc = !!(dev->flags & IFF_PROMISC);
588         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
589         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
590
591         if (allmulti != sdata_allmulti) {
592                 if (dev->flags & IFF_ALLMULTI)
593                         atomic_inc(&local->iff_allmultis);
594                 else
595                         atomic_dec(&local->iff_allmultis);
596                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
597         }
598
599         if (promisc != sdata_promisc) {
600                 if (dev->flags & IFF_PROMISC)
601                         atomic_inc(&local->iff_promiscs);
602                 else
603                         atomic_dec(&local->iff_promiscs);
604                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
605         }
606
607         dev_mc_sync(local->mdev, dev);
608 }
609
610 /*
611  * Called when the netdev is removed or, by the code below, before
612  * the interface type changes.
613  */
614 static void ieee80211_teardown_sdata(struct net_device *dev)
615 {
616         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
617         struct ieee80211_local *local = sdata->local;
618         struct beacon_data *beacon;
619         struct sk_buff *skb;
620         int flushed;
621         int i;
622
623         /* free extra data */
624         ieee80211_free_keys(sdata);
625
626         ieee80211_debugfs_remove_netdev(sdata);
627
628         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
629                 __skb_queue_purge(&sdata->fragments[i].skb_list);
630         sdata->fragment_next = 0;
631
632         switch (sdata->vif.type) {
633         case NL80211_IFTYPE_AP:
634                 beacon = sdata->u.ap.beacon;
635                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
636                 synchronize_rcu();
637                 kfree(beacon);
638
639                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
640                         local->total_ps_buffered--;
641                         dev_kfree_skb(skb);
642                 }
643
644                 break;
645         case NL80211_IFTYPE_MESH_POINT:
646                 if (ieee80211_vif_is_mesh(&sdata->vif))
647                         mesh_rmc_free(sdata);
648                 break;
649         case NL80211_IFTYPE_ADHOC:
650                 kfree_skb(sdata->u.ibss.probe_resp);
651                 break;
652         case NL80211_IFTYPE_STATION:
653                 kfree(sdata->u.mgd.extra_ie);
654                 kfree(sdata->u.mgd.assocreq_ies);
655                 kfree(sdata->u.mgd.assocresp_ies);
656                 kfree(sdata->u.mgd.ie_probereq);
657                 kfree(sdata->u.mgd.ie_proberesp);
658                 kfree(sdata->u.mgd.ie_auth);
659                 kfree(sdata->u.mgd.ie_assocreq);
660                 kfree(sdata->u.mgd.ie_reassocreq);
661                 kfree(sdata->u.mgd.ie_deauth);
662                 kfree(sdata->u.mgd.ie_disassoc);
663                 break;
664         case NL80211_IFTYPE_WDS:
665         case NL80211_IFTYPE_AP_VLAN:
666         case NL80211_IFTYPE_MONITOR:
667                 break;
668         case NL80211_IFTYPE_UNSPECIFIED:
669         case __NL80211_IFTYPE_AFTER_LAST:
670                 BUG();
671                 break;
672         }
673
674         flushed = sta_info_flush(local, sdata);
675         WARN_ON(flushed);
676 }
677
678 static const struct net_device_ops ieee80211_dataif_ops = {
679         .ndo_open               = ieee80211_open,
680         .ndo_stop               = ieee80211_stop,
681         .ndo_uninit             = ieee80211_teardown_sdata,
682         .ndo_start_xmit         = ieee80211_subif_start_xmit,
683         .ndo_set_multicast_list = ieee80211_set_multicast_list,
684         .ndo_change_mtu         = ieee80211_change_mtu,
685         .ndo_set_mac_address    = eth_mac_addr,
686 };
687
688 static const struct net_device_ops ieee80211_monitorif_ops = {
689         .ndo_open               = ieee80211_open,
690         .ndo_stop               = ieee80211_stop,
691         .ndo_uninit             = ieee80211_teardown_sdata,
692         .ndo_start_xmit         = ieee80211_monitor_start_xmit,
693         .ndo_set_multicast_list = ieee80211_set_multicast_list,
694         .ndo_change_mtu         = ieee80211_change_mtu,
695         .ndo_set_mac_address    = eth_mac_addr,
696 };
697
698 static void ieee80211_if_setup(struct net_device *dev)
699 {
700         ether_setup(dev);
701         dev->netdev_ops = &ieee80211_dataif_ops;
702         dev->wireless_handlers = &ieee80211_iw_handler_def;
703         dev->destructor = free_netdev;
704 }
705
706 /*
707  * Helper function to initialise an interface to a specific type.
708  */
709 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
710                                   enum nl80211_iftype type)
711 {
712         /* clear type-dependent union */
713         memset(&sdata->u, 0, sizeof(sdata->u));
714
715         /* and set some type-dependent values */
716         sdata->vif.type = type;
717         sdata->dev->netdev_ops = &ieee80211_dataif_ops;
718         sdata->wdev.iftype = type;
719
720         /* only monitor differs */
721         sdata->dev->type = ARPHRD_ETHER;
722
723         switch (type) {
724         case NL80211_IFTYPE_AP:
725                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
726                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
727                 break;
728         case NL80211_IFTYPE_STATION:
729                 ieee80211_sta_setup_sdata(sdata);
730                 break;
731         case NL80211_IFTYPE_ADHOC:
732                 ieee80211_ibss_setup_sdata(sdata);
733                 break;
734         case NL80211_IFTYPE_MESH_POINT:
735                 if (ieee80211_vif_is_mesh(&sdata->vif))
736                         ieee80211_mesh_init_sdata(sdata);
737                 break;
738         case NL80211_IFTYPE_MONITOR:
739                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
740                 sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
741                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
742                                       MONITOR_FLAG_OTHER_BSS;
743                 break;
744         case NL80211_IFTYPE_WDS:
745         case NL80211_IFTYPE_AP_VLAN:
746                 break;
747         case NL80211_IFTYPE_UNSPECIFIED:
748         case __NL80211_IFTYPE_AFTER_LAST:
749                 BUG();
750                 break;
751         }
752
753         ieee80211_debugfs_add_netdev(sdata);
754 }
755
756 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
757                              enum nl80211_iftype type)
758 {
759         ASSERT_RTNL();
760
761         if (type == sdata->vif.type)
762                 return 0;
763
764         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
765         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
766             type == NL80211_IFTYPE_ADHOC)
767                 return -EOPNOTSUPP;
768
769         /*
770          * We could, here, on changes between IBSS/STA/MESH modes,
771          * invoke an MLME function instead that disassociates etc.
772          * and goes into the requested mode.
773          */
774
775         if (netif_running(sdata->dev))
776                 return -EBUSY;
777
778         /* Purge and reset type-dependent state. */
779         ieee80211_teardown_sdata(sdata->dev);
780         ieee80211_setup_sdata(sdata, type);
781
782         /* reset some values that shouldn't be kept across type changes */
783         sdata->vif.bss_conf.basic_rates =
784                 ieee80211_mandatory_rates(sdata->local,
785                         sdata->local->hw.conf.channel->band);
786         sdata->drop_unencrypted = 0;
787
788         return 0;
789 }
790
791 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
792                      struct net_device **new_dev, enum nl80211_iftype type,
793                      struct vif_params *params)
794 {
795         struct net_device *ndev;
796         struct ieee80211_sub_if_data *sdata = NULL;
797         int ret, i;
798
799         ASSERT_RTNL();
800
801         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
802                             name, ieee80211_if_setup);
803         if (!ndev)
804                 return -ENOMEM;
805
806         ndev->needed_headroom = local->tx_headroom +
807                                 4*6 /* four MAC addresses */
808                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
809                                 + 6 /* mesh */
810                                 + 8 /* rfc1042/bridge tunnel */
811                                 - ETH_HLEN /* ethernet hard_header_len */
812                                 + IEEE80211_ENCRYPT_HEADROOM;
813         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
814
815         ret = dev_alloc_name(ndev, ndev->name);
816         if (ret < 0)
817                 goto fail;
818
819         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
820         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
821         ndev->features |= NETIF_F_NETNS_LOCAL;
822
823         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
824         sdata = netdev_priv(ndev);
825         ndev->ieee80211_ptr = &sdata->wdev;
826
827         /* initialise type-independent data */
828         sdata->wdev.wiphy = local->hw.wiphy;
829         sdata->local = local;
830         sdata->dev = ndev;
831
832         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
833                 skb_queue_head_init(&sdata->fragments[i].skb_list);
834
835         INIT_LIST_HEAD(&sdata->key_list);
836
837         sdata->force_unicast_rateidx = -1;
838         sdata->max_ratectrl_rateidx = -1;
839
840         /* setup type-dependent data */
841         ieee80211_setup_sdata(sdata, type);
842
843         ret = register_netdevice(ndev);
844         if (ret)
845                 goto fail;
846
847         if (ieee80211_vif_is_mesh(&sdata->vif) &&
848             params && params->mesh_id_len)
849                 ieee80211_sdata_set_mesh_id(sdata,
850                                             params->mesh_id_len,
851                                             params->mesh_id);
852
853         mutex_lock(&local->iflist_mtx);
854         list_add_tail_rcu(&sdata->list, &local->interfaces);
855         mutex_unlock(&local->iflist_mtx);
856
857         if (new_dev)
858                 *new_dev = ndev;
859
860         return 0;
861
862  fail:
863         free_netdev(ndev);
864         return ret;
865 }
866
867 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
868 {
869         ASSERT_RTNL();
870
871         mutex_lock(&sdata->local->iflist_mtx);
872         list_del_rcu(&sdata->list);
873         mutex_unlock(&sdata->local->iflist_mtx);
874
875         synchronize_rcu();
876         unregister_netdevice(sdata->dev);
877 }
878
879 /*
880  * Remove all interfaces, may only be called at hardware unregistration
881  * time because it doesn't do RCU-safe list removals.
882  */
883 void ieee80211_remove_interfaces(struct ieee80211_local *local)
884 {
885         struct ieee80211_sub_if_data *sdata, *tmp;
886
887         ASSERT_RTNL();
888
889         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
890                 /*
891                  * we cannot hold the iflist_mtx across unregister_netdevice,
892                  * but we only need to hold it for list modifications to lock
893                  * out readers since we're under the RTNL here as all other
894                  * writers.
895                  */
896                 mutex_lock(&local->iflist_mtx);
897                 list_del(&sdata->list);
898                 mutex_unlock(&local->iflist_mtx);
899
900                 unregister_netdevice(sdata->dev);
901         }
902 }