xref: /linux/net/mac80211/iface.c (revision 5d4a2e29fba5b2bef95b96a46b338ec4d76fa4fd)
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/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/if_arp.h>
16 #include <linux/netdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20 #include "ieee80211_i.h"
21 #include "sta_info.h"
22 #include "debugfs_netdev.h"
23 #include "mesh.h"
24 #include "led.h"
25 #include "driver-ops.h"
26 #include "wme.h"
27 
28 /**
29  * DOC: Interface list locking
30  *
31  * The interface list in each struct ieee80211_local is protected
32  * three-fold:
33  *
34  * (1) modifications may only be done under the RTNL
35  * (2) modifications and readers are protected against each other by
36  *     the iflist_mtx.
37  * (3) modifications are done in an RCU manner so atomic readers
38  *     can traverse the list in RCU-safe blocks.
39  *
40  * As a consequence, reads (traversals) of the list can be protected
41  * by either the RTNL, the iflist_mtx or RCU.
42  */
43 
44 
45 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
46 {
47 	int meshhdrlen;
48 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
49 
50 	meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
51 
52 	/* FIX: what would be proper limits for MTU?
53 	 * This interface uses 802.3 frames. */
54 	if (new_mtu < 256 ||
55 	    new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
56 		return -EINVAL;
57 	}
58 
59 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
60 	printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
61 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
62 	dev->mtu = new_mtu;
63 	return 0;
64 }
65 
66 static int ieee80211_change_mac(struct net_device *dev, void *addr)
67 {
68 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
69 	struct sockaddr *sa = addr;
70 	int ret;
71 
72 	if (ieee80211_sdata_running(sdata))
73 		return -EBUSY;
74 
75 	ret = eth_mac_addr(dev, sa);
76 
77 	if (ret == 0)
78 		memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);
79 
80 	return ret;
81 }
82 
83 static inline int identical_mac_addr_allowed(int type1, int type2)
84 {
85 	return type1 == NL80211_IFTYPE_MONITOR ||
86 		type2 == NL80211_IFTYPE_MONITOR ||
87 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
88 		(type1 == NL80211_IFTYPE_WDS &&
89 			(type2 == NL80211_IFTYPE_WDS ||
90 			 type2 == NL80211_IFTYPE_AP)) ||
91 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
92 		(type1 == NL80211_IFTYPE_AP_VLAN &&
93 			(type2 == NL80211_IFTYPE_AP ||
94 			 type2 == NL80211_IFTYPE_AP_VLAN));
95 }
96 
97 static int ieee80211_open(struct net_device *dev)
98 {
99 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
100 	struct ieee80211_sub_if_data *nsdata;
101 	struct ieee80211_local *local = sdata->local;
102 	struct sta_info *sta;
103 	u32 changed = 0;
104 	int res;
105 	u32 hw_reconf_flags = 0;
106 	u8 null_addr[ETH_ALEN] = {0};
107 
108 	/* fail early if user set an invalid address */
109 	if (compare_ether_addr(dev->dev_addr, null_addr) &&
110 	    !is_valid_ether_addr(dev->dev_addr))
111 		return -EADDRNOTAVAIL;
112 
113 	/* we hold the RTNL here so can safely walk the list */
114 	list_for_each_entry(nsdata, &local->interfaces, list) {
115 		struct net_device *ndev = nsdata->dev;
116 
117 		if (ndev != dev && ieee80211_sdata_running(nsdata)) {
118 			/*
119 			 * Allow only a single IBSS interface to be up at any
120 			 * time. This is restricted because beacon distribution
121 			 * cannot work properly if both are in the same IBSS.
122 			 *
123 			 * To remove this restriction we'd have to disallow them
124 			 * from setting the same SSID on different IBSS interfaces
125 			 * belonging to the same hardware. Then, however, we're
126 			 * faced with having to adopt two different TSF timers...
127 			 */
128 			if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
129 			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
130 				return -EBUSY;
131 
132 			/*
133 			 * The remaining checks are only performed for interfaces
134 			 * with the same MAC address.
135 			 */
136 			if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
137 				continue;
138 
139 			/*
140 			 * check whether it may have the same address
141 			 */
142 			if (!identical_mac_addr_allowed(sdata->vif.type,
143 							nsdata->vif.type))
144 				return -ENOTUNIQ;
145 
146 			/*
147 			 * can only add VLANs to enabled APs
148 			 */
149 			if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
150 			    nsdata->vif.type == NL80211_IFTYPE_AP)
151 				sdata->bss = &nsdata->u.ap;
152 		}
153 	}
154 
155 	switch (sdata->vif.type) {
156 	case NL80211_IFTYPE_WDS:
157 		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
158 			return -ENOLINK;
159 		break;
160 	case NL80211_IFTYPE_AP_VLAN:
161 		if (!sdata->bss)
162 			return -ENOLINK;
163 		list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
164 		break;
165 	case NL80211_IFTYPE_AP:
166 		sdata->bss = &sdata->u.ap;
167 		break;
168 	case NL80211_IFTYPE_MESH_POINT:
169 		if (!ieee80211_vif_is_mesh(&sdata->vif))
170 			break;
171 		/* mesh ifaces must set allmulti to forward mcast traffic */
172 		atomic_inc(&local->iff_allmultis);
173 		break;
174 	case NL80211_IFTYPE_STATION:
175 	case NL80211_IFTYPE_MONITOR:
176 	case NL80211_IFTYPE_ADHOC:
177 		/* no special treatment */
178 		break;
179 	case NL80211_IFTYPE_UNSPECIFIED:
180 	case __NL80211_IFTYPE_AFTER_LAST:
181 		/* cannot happen */
182 		WARN_ON(1);
183 		break;
184 	}
185 
186 	if (local->open_count == 0) {
187 		res = drv_start(local);
188 		if (res)
189 			goto err_del_bss;
190 		/* we're brought up, everything changes */
191 		hw_reconf_flags = ~0;
192 		ieee80211_led_radio(local, true);
193 	}
194 
195 	/*
196 	 * Check all interfaces and copy the hopefully now-present
197 	 * MAC address to those that have the special null one.
198 	 */
199 	list_for_each_entry(nsdata, &local->interfaces, list) {
200 		struct net_device *ndev = nsdata->dev;
201 
202 		/*
203 		 * No need to check running since we do not allow
204 		 * it to start up with this invalid address.
205 		 */
206 		if (compare_ether_addr(null_addr, ndev->dev_addr) == 0) {
207 			memcpy(ndev->dev_addr,
208 			       local->hw.wiphy->perm_addr,
209 			       ETH_ALEN);
210 			memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
211 		}
212 	}
213 
214 	/*
215 	 * Validate the MAC address for this device.
216 	 */
217 	if (!is_valid_ether_addr(dev->dev_addr)) {
218 		if (!local->open_count)
219 			drv_stop(local);
220 		return -EADDRNOTAVAIL;
221 	}
222 
223 	switch (sdata->vif.type) {
224 	case NL80211_IFTYPE_AP_VLAN:
225 		/* no need to tell driver */
226 		break;
227 	case NL80211_IFTYPE_MONITOR:
228 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
229 			local->cooked_mntrs++;
230 			break;
231 		}
232 
233 		/* must be before the call to ieee80211_configure_filter */
234 		local->monitors++;
235 		if (local->monitors == 1) {
236 			local->hw.conf.flags |= IEEE80211_CONF_MONITOR;
237 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
238 		}
239 
240 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
241 			local->fif_fcsfail++;
242 		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
243 			local->fif_plcpfail++;
244 		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL) {
245 			local->fif_control++;
246 			local->fif_pspoll++;
247 		}
248 		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
249 			local->fif_other_bss++;
250 
251 		ieee80211_configure_filter(local);
252 		break;
253 	default:
254 		res = drv_add_interface(local, &sdata->vif);
255 		if (res)
256 			goto err_stop;
257 
258 		if (ieee80211_vif_is_mesh(&sdata->vif)) {
259 			local->fif_other_bss++;
260 			ieee80211_configure_filter(local);
261 
262 			ieee80211_start_mesh(sdata);
263 		} else if (sdata->vif.type == NL80211_IFTYPE_AP) {
264 			local->fif_pspoll++;
265 
266 			ieee80211_configure_filter(local);
267 		}
268 
269 		changed |= ieee80211_reset_erp_info(sdata);
270 		ieee80211_bss_info_change_notify(sdata, changed);
271 		ieee80211_enable_keys(sdata);
272 
273 		if (sdata->vif.type == NL80211_IFTYPE_STATION)
274 			netif_carrier_off(dev);
275 		else
276 			netif_carrier_on(dev);
277 	}
278 
279 	if (sdata->vif.type == NL80211_IFTYPE_WDS) {
280 		/* Create STA entry for the WDS peer */
281 		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
282 				     GFP_KERNEL);
283 		if (!sta) {
284 			res = -ENOMEM;
285 			goto err_del_interface;
286 		}
287 
288 		/* no locking required since STA is not live yet */
289 		sta->flags |= WLAN_STA_AUTHORIZED;
290 
291 		res = sta_info_insert(sta);
292 		if (res) {
293 			/* STA has been freed */
294 			goto err_del_interface;
295 		}
296 	}
297 
298 	/*
299 	 * set_multicast_list will be invoked by the networking core
300 	 * which will check whether any increments here were done in
301 	 * error and sync them down to the hardware as filter flags.
302 	 */
303 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
304 		atomic_inc(&local->iff_allmultis);
305 
306 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
307 		atomic_inc(&local->iff_promiscs);
308 
309 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
310 
311 	local->open_count++;
312 	if (hw_reconf_flags) {
313 		ieee80211_hw_config(local, hw_reconf_flags);
314 		/*
315 		 * set default queue parameters so drivers don't
316 		 * need to initialise the hardware if the hardware
317 		 * doesn't start up with sane defaults
318 		 */
319 		ieee80211_set_wmm_default(sdata);
320 	}
321 
322 	ieee80211_recalc_ps(local, -1);
323 
324 	/*
325 	 * ieee80211_sta_work is disabled while network interface
326 	 * is down. Therefore, some configuration changes may not
327 	 * yet be effective. Trigger execution of ieee80211_sta_work
328 	 * to fix this.
329 	 */
330 	if (sdata->vif.type == NL80211_IFTYPE_STATION)
331 		ieee80211_queue_work(&local->hw, &sdata->u.mgd.work);
332 
333 	netif_tx_start_all_queues(dev);
334 
335 	return 0;
336  err_del_interface:
337 	drv_remove_interface(local, &sdata->vif);
338  err_stop:
339 	if (!local->open_count)
340 		drv_stop(local);
341  err_del_bss:
342 	sdata->bss = NULL;
343 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
344 		list_del(&sdata->u.vlan.list);
345 	return res;
346 }
347 
348 static int ieee80211_stop(struct net_device *dev)
349 {
350 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
351 	struct ieee80211_local *local = sdata->local;
352 	struct sta_info *sta;
353 	unsigned long flags;
354 	struct sk_buff *skb, *tmp;
355 	u32 hw_reconf_flags = 0;
356 	int i;
357 
358 	/*
359 	 * Stop TX on this interface first.
360 	 */
361 	netif_tx_stop_all_queues(dev);
362 
363 	/*
364 	 * Purge work for this interface.
365 	 */
366 	ieee80211_work_purge(sdata);
367 
368 	/*
369 	 * Now delete all active aggregation sessions.
370 	 */
371 	rcu_read_lock();
372 
373 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
374 		if (sta->sdata == sdata)
375 			ieee80211_sta_tear_down_BA_sessions(sta);
376 	}
377 
378 	rcu_read_unlock();
379 
380 	/*
381 	 * Remove all stations associated with this interface.
382 	 *
383 	 * This must be done before calling ops->remove_interface()
384 	 * because otherwise we can later invoke ops->sta_notify()
385 	 * whenever the STAs are removed, and that invalidates driver
386 	 * assumptions about always getting a vif pointer that is valid
387 	 * (because if we remove a STA after ops->remove_interface()
388 	 * the driver will have removed the vif info already!)
389 	 *
390 	 * We could relax this and only unlink the stations from the
391 	 * hash table and list but keep them on a per-sdata list that
392 	 * will be inserted back again when the interface is brought
393 	 * up again, but I don't currently see a use case for that,
394 	 * except with WDS which gets a STA entry created when it is
395 	 * brought up.
396 	 */
397 	sta_info_flush(local, sdata);
398 
399 	/*
400 	 * Don't count this interface for promisc/allmulti while it
401 	 * is down. dev_mc_unsync() will invoke set_multicast_list
402 	 * on the master interface which will sync these down to the
403 	 * hardware as filter flags.
404 	 */
405 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
406 		atomic_dec(&local->iff_allmultis);
407 
408 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
409 		atomic_dec(&local->iff_promiscs);
410 
411 	if (sdata->vif.type == NL80211_IFTYPE_AP)
412 		local->fif_pspoll--;
413 
414 	netif_addr_lock_bh(dev);
415 	spin_lock_bh(&local->filter_lock);
416 	__hw_addr_unsync(&local->mc_list, &dev->mc, dev->addr_len);
417 	spin_unlock_bh(&local->filter_lock);
418 	netif_addr_unlock_bh(dev);
419 
420 	ieee80211_configure_filter(local);
421 
422 	del_timer_sync(&local->dynamic_ps_timer);
423 	cancel_work_sync(&local->dynamic_ps_enable_work);
424 
425 	/* APs need special treatment */
426 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
427 		struct ieee80211_sub_if_data *vlan, *tmpsdata;
428 		struct beacon_data *old_beacon = sdata->u.ap.beacon;
429 
430 		/* remove beacon */
431 		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
432 		synchronize_rcu();
433 		kfree(old_beacon);
434 
435 		/* down all dependent devices, that is VLANs */
436 		list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
437 					 u.vlan.list)
438 			dev_close(vlan->dev);
439 		WARN_ON(!list_empty(&sdata->u.ap.vlans));
440 	}
441 
442 	local->open_count--;
443 
444 	switch (sdata->vif.type) {
445 	case NL80211_IFTYPE_AP_VLAN:
446 		list_del(&sdata->u.vlan.list);
447 		/* no need to tell driver */
448 		break;
449 	case NL80211_IFTYPE_MONITOR:
450 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
451 			local->cooked_mntrs--;
452 			break;
453 		}
454 
455 		local->monitors--;
456 		if (local->monitors == 0) {
457 			local->hw.conf.flags &= ~IEEE80211_CONF_MONITOR;
458 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
459 		}
460 
461 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
462 			local->fif_fcsfail--;
463 		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
464 			local->fif_plcpfail--;
465 		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL) {
466 			local->fif_pspoll--;
467 			local->fif_control--;
468 		}
469 		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
470 			local->fif_other_bss--;
471 
472 		ieee80211_configure_filter(local);
473 		break;
474 	case NL80211_IFTYPE_STATION:
475 		del_timer_sync(&sdata->u.mgd.chswitch_timer);
476 		del_timer_sync(&sdata->u.mgd.timer);
477 		del_timer_sync(&sdata->u.mgd.conn_mon_timer);
478 		del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
479 		/*
480 		 * If any of the timers fired while we waited for it, it will
481 		 * have queued its work. Now the work will be running again
482 		 * but will not rearm the timer again because it checks
483 		 * whether the interface is running, which, at this point,
484 		 * it no longer is.
485 		 */
486 		cancel_work_sync(&sdata->u.mgd.work);
487 		cancel_work_sync(&sdata->u.mgd.chswitch_work);
488 		cancel_work_sync(&sdata->u.mgd.monitor_work);
489 		cancel_work_sync(&sdata->u.mgd.beacon_connection_loss_work);
490 
491 		/*
492 		 * When we get here, the interface is marked down.
493 		 * Call synchronize_rcu() to wait for the RX path
494 		 * should it be using the interface and enqueuing
495 		 * frames at this very time on another CPU.
496 		 */
497 		synchronize_rcu();
498 		skb_queue_purge(&sdata->u.mgd.skb_queue);
499 		/* fall through */
500 	case NL80211_IFTYPE_ADHOC:
501 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
502 			del_timer_sync(&sdata->u.ibss.timer);
503 			cancel_work_sync(&sdata->u.ibss.work);
504 			synchronize_rcu();
505 			skb_queue_purge(&sdata->u.ibss.skb_queue);
506 		}
507 		/* fall through */
508 	case NL80211_IFTYPE_MESH_POINT:
509 		if (ieee80211_vif_is_mesh(&sdata->vif)) {
510 			/* other_bss and allmulti are always set on mesh
511 			 * ifaces */
512 			local->fif_other_bss--;
513 			atomic_dec(&local->iff_allmultis);
514 
515 			ieee80211_configure_filter(local);
516 
517 			ieee80211_stop_mesh(sdata);
518 		}
519 		/* fall through */
520 	default:
521 		if (local->scan_sdata == sdata)
522 			ieee80211_scan_cancel(local);
523 
524 		/*
525 		 * Disable beaconing for AP and mesh, IBSS can't
526 		 * still be joined to a network at this point.
527 		 */
528 		if (sdata->vif.type == NL80211_IFTYPE_AP ||
529 		    sdata->vif.type == NL80211_IFTYPE_MESH_POINT) {
530 			ieee80211_bss_info_change_notify(sdata,
531 				BSS_CHANGED_BEACON_ENABLED);
532 		}
533 
534 		/* disable all keys for as long as this netdev is down */
535 		ieee80211_disable_keys(sdata);
536 		drv_remove_interface(local, &sdata->vif);
537 	}
538 
539 	sdata->bss = NULL;
540 
541 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
542 
543 	ieee80211_recalc_ps(local, -1);
544 
545 	if (local->open_count == 0) {
546 		ieee80211_clear_tx_pending(local);
547 		ieee80211_stop_device(local);
548 
549 		/* no reconfiguring after stop! */
550 		hw_reconf_flags = 0;
551 	}
552 
553 	/* do after stop to avoid reconfiguring when we stop anyway */
554 	if (hw_reconf_flags)
555 		ieee80211_hw_config(local, hw_reconf_flags);
556 
557 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
558 	for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
559 		skb_queue_walk_safe(&local->pending[i], skb, tmp) {
560 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
561 			if (info->control.vif == &sdata->vif) {
562 				__skb_unlink(skb, &local->pending[i]);
563 				dev_kfree_skb_irq(skb);
564 			}
565 		}
566 	}
567 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
568 
569 	return 0;
570 }
571 
572 static void ieee80211_set_multicast_list(struct net_device *dev)
573 {
574 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
575 	struct ieee80211_local *local = sdata->local;
576 	int allmulti, promisc, sdata_allmulti, sdata_promisc;
577 
578 	allmulti = !!(dev->flags & IFF_ALLMULTI);
579 	promisc = !!(dev->flags & IFF_PROMISC);
580 	sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
581 	sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
582 
583 	if (allmulti != sdata_allmulti) {
584 		if (dev->flags & IFF_ALLMULTI)
585 			atomic_inc(&local->iff_allmultis);
586 		else
587 			atomic_dec(&local->iff_allmultis);
588 		sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
589 	}
590 
591 	if (promisc != sdata_promisc) {
592 		if (dev->flags & IFF_PROMISC)
593 			atomic_inc(&local->iff_promiscs);
594 		else
595 			atomic_dec(&local->iff_promiscs);
596 		sdata->flags ^= IEEE80211_SDATA_PROMISC;
597 	}
598 	spin_lock_bh(&local->filter_lock);
599 	__hw_addr_sync(&local->mc_list, &dev->mc, dev->addr_len);
600 	spin_unlock_bh(&local->filter_lock);
601 	ieee80211_queue_work(&local->hw, &local->reconfig_filter);
602 }
603 
604 /*
605  * Called when the netdev is removed or, by the code below, before
606  * the interface type changes.
607  */
608 static void ieee80211_teardown_sdata(struct net_device *dev)
609 {
610 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
611 	struct ieee80211_local *local = sdata->local;
612 	struct beacon_data *beacon;
613 	struct sk_buff *skb;
614 	int flushed;
615 	int i;
616 
617 	/* free extra data */
618 	ieee80211_free_keys(sdata);
619 
620 	ieee80211_debugfs_remove_netdev(sdata);
621 
622 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
623 		__skb_queue_purge(&sdata->fragments[i].skb_list);
624 	sdata->fragment_next = 0;
625 
626 	switch (sdata->vif.type) {
627 	case NL80211_IFTYPE_AP:
628 		beacon = sdata->u.ap.beacon;
629 		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
630 		synchronize_rcu();
631 		kfree(beacon);
632 
633 		while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
634 			local->total_ps_buffered--;
635 			dev_kfree_skb(skb);
636 		}
637 
638 		break;
639 	case NL80211_IFTYPE_MESH_POINT:
640 		if (ieee80211_vif_is_mesh(&sdata->vif))
641 			mesh_rmc_free(sdata);
642 		break;
643 	case NL80211_IFTYPE_ADHOC:
644 		if (WARN_ON(sdata->u.ibss.presp))
645 			kfree_skb(sdata->u.ibss.presp);
646 		break;
647 	case NL80211_IFTYPE_STATION:
648 	case NL80211_IFTYPE_WDS:
649 	case NL80211_IFTYPE_AP_VLAN:
650 	case NL80211_IFTYPE_MONITOR:
651 		break;
652 	case NL80211_IFTYPE_UNSPECIFIED:
653 	case __NL80211_IFTYPE_AFTER_LAST:
654 		BUG();
655 		break;
656 	}
657 
658 	flushed = sta_info_flush(local, sdata);
659 	WARN_ON(flushed);
660 }
661 
662 static u16 ieee80211_netdev_select_queue(struct net_device *dev,
663 					 struct sk_buff *skb)
664 {
665 	return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb);
666 }
667 
668 static const struct net_device_ops ieee80211_dataif_ops = {
669 	.ndo_open		= ieee80211_open,
670 	.ndo_stop		= ieee80211_stop,
671 	.ndo_uninit		= ieee80211_teardown_sdata,
672 	.ndo_start_xmit		= ieee80211_subif_start_xmit,
673 	.ndo_set_multicast_list = ieee80211_set_multicast_list,
674 	.ndo_change_mtu 	= ieee80211_change_mtu,
675 	.ndo_set_mac_address 	= ieee80211_change_mac,
676 	.ndo_select_queue	= ieee80211_netdev_select_queue,
677 };
678 
679 static u16 ieee80211_monitor_select_queue(struct net_device *dev,
680 					  struct sk_buff *skb)
681 {
682 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
683 	struct ieee80211_local *local = sdata->local;
684 	struct ieee80211_hdr *hdr;
685 	struct ieee80211_radiotap_header *rtap = (void *)skb->data;
686 	u8 *p;
687 
688 	if (local->hw.queues < 4)
689 		return 0;
690 
691 	if (skb->len < 4 ||
692 	    skb->len < le16_to_cpu(rtap->it_len) + 2 /* frame control */)
693 		return 0; /* doesn't matter, frame will be dropped */
694 
695 	hdr = (void *)((u8 *)skb->data + le16_to_cpu(rtap->it_len));
696 
697 	if (!ieee80211_is_data(hdr->frame_control)) {
698 		skb->priority = 7;
699 		return ieee802_1d_to_ac[skb->priority];
700 	}
701 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
702 		skb->priority = 0;
703 		return ieee802_1d_to_ac[skb->priority];
704 	}
705 
706 	p = ieee80211_get_qos_ctl(hdr);
707 	skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
708 
709 	return ieee80211_downgrade_queue(local, skb);
710 }
711 
712 static const struct net_device_ops ieee80211_monitorif_ops = {
713 	.ndo_open		= ieee80211_open,
714 	.ndo_stop		= ieee80211_stop,
715 	.ndo_uninit		= ieee80211_teardown_sdata,
716 	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
717 	.ndo_set_multicast_list = ieee80211_set_multicast_list,
718 	.ndo_change_mtu 	= ieee80211_change_mtu,
719 	.ndo_set_mac_address 	= eth_mac_addr,
720 	.ndo_select_queue	= ieee80211_monitor_select_queue,
721 };
722 
723 static void ieee80211_if_setup(struct net_device *dev)
724 {
725 	ether_setup(dev);
726 	dev->netdev_ops = &ieee80211_dataif_ops;
727 	dev->destructor = free_netdev;
728 }
729 
730 /*
731  * Helper function to initialise an interface to a specific type.
732  */
733 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
734 				  enum nl80211_iftype type)
735 {
736 	/* clear type-dependent union */
737 	memset(&sdata->u, 0, sizeof(sdata->u));
738 
739 	/* and set some type-dependent values */
740 	sdata->vif.type = type;
741 	sdata->dev->netdev_ops = &ieee80211_dataif_ops;
742 	sdata->wdev.iftype = type;
743 
744 	/* only monitor differs */
745 	sdata->dev->type = ARPHRD_ETHER;
746 
747 	switch (type) {
748 	case NL80211_IFTYPE_AP:
749 		skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
750 		INIT_LIST_HEAD(&sdata->u.ap.vlans);
751 		break;
752 	case NL80211_IFTYPE_STATION:
753 		ieee80211_sta_setup_sdata(sdata);
754 		break;
755 	case NL80211_IFTYPE_ADHOC:
756 		ieee80211_ibss_setup_sdata(sdata);
757 		break;
758 	case NL80211_IFTYPE_MESH_POINT:
759 		if (ieee80211_vif_is_mesh(&sdata->vif))
760 			ieee80211_mesh_init_sdata(sdata);
761 		break;
762 	case NL80211_IFTYPE_MONITOR:
763 		sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
764 		sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
765 		sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
766 				      MONITOR_FLAG_OTHER_BSS;
767 		break;
768 	case NL80211_IFTYPE_WDS:
769 	case NL80211_IFTYPE_AP_VLAN:
770 		break;
771 	case NL80211_IFTYPE_UNSPECIFIED:
772 	case __NL80211_IFTYPE_AFTER_LAST:
773 		BUG();
774 		break;
775 	}
776 
777 	ieee80211_debugfs_add_netdev(sdata);
778 }
779 
780 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
781 			     enum nl80211_iftype type)
782 {
783 	ASSERT_RTNL();
784 
785 	if (type == sdata->vif.type)
786 		return 0;
787 
788 	/* Setting ad-hoc mode on non-IBSS channel is not supported. */
789 	if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
790 	    type == NL80211_IFTYPE_ADHOC)
791 		return -EOPNOTSUPP;
792 
793 	/*
794 	 * We could, here, on changes between IBSS/STA/MESH modes,
795 	 * invoke an MLME function instead that disassociates etc.
796 	 * and goes into the requested mode.
797 	 */
798 
799 	if (ieee80211_sdata_running(sdata))
800 		return -EBUSY;
801 
802 	/* Purge and reset type-dependent state. */
803 	ieee80211_teardown_sdata(sdata->dev);
804 	ieee80211_setup_sdata(sdata, type);
805 
806 	/* reset some values that shouldn't be kept across type changes */
807 	sdata->vif.bss_conf.basic_rates =
808 		ieee80211_mandatory_rates(sdata->local,
809 			sdata->local->hw.conf.channel->band);
810 	sdata->drop_unencrypted = 0;
811 	if (type == NL80211_IFTYPE_STATION)
812 		sdata->u.mgd.use_4addr = false;
813 
814 	return 0;
815 }
816 
817 static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
818 				       struct net_device *dev,
819 				       enum nl80211_iftype type)
820 {
821 	struct ieee80211_sub_if_data *sdata;
822 	u64 mask, start, addr, val, inc;
823 	u8 *m;
824 	u8 tmp_addr[ETH_ALEN];
825 	int i;
826 
827 	/* default ... something at least */
828 	memcpy(dev->perm_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
829 
830 	if (is_zero_ether_addr(local->hw.wiphy->addr_mask) &&
831 	    local->hw.wiphy->n_addresses <= 1)
832 		return;
833 
834 
835 	mutex_lock(&local->iflist_mtx);
836 
837 	switch (type) {
838 	case NL80211_IFTYPE_MONITOR:
839 		/* doesn't matter */
840 		break;
841 	case NL80211_IFTYPE_WDS:
842 	case NL80211_IFTYPE_AP_VLAN:
843 		/* match up with an AP interface */
844 		list_for_each_entry(sdata, &local->interfaces, list) {
845 			if (sdata->vif.type != NL80211_IFTYPE_AP)
846 				continue;
847 			memcpy(dev->perm_addr, sdata->vif.addr, ETH_ALEN);
848 			break;
849 		}
850 		/* keep default if no AP interface present */
851 		break;
852 	default:
853 		/* assign a new address if possible -- try n_addresses first */
854 		for (i = 0; i < local->hw.wiphy->n_addresses; i++) {
855 			bool used = false;
856 
857 			list_for_each_entry(sdata, &local->interfaces, list) {
858 				if (memcmp(local->hw.wiphy->addresses[i].addr,
859 					   sdata->vif.addr, ETH_ALEN) == 0) {
860 					used = true;
861 					break;
862 				}
863 			}
864 
865 			if (!used) {
866 				memcpy(dev->perm_addr,
867 				       local->hw.wiphy->addresses[i].addr,
868 				       ETH_ALEN);
869 				break;
870 			}
871 		}
872 
873 		/* try mask if available */
874 		if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
875 			break;
876 
877 		m = local->hw.wiphy->addr_mask;
878 		mask =	((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
879 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
880 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
881 
882 		if (__ffs64(mask) + hweight64(mask) != fls64(mask)) {
883 			/* not a contiguous mask ... not handled now! */
884 			printk(KERN_DEBUG "not contiguous\n");
885 			break;
886 		}
887 
888 		m = local->hw.wiphy->perm_addr;
889 		start = ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
890 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
891 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
892 
893 		inc = 1ULL<<__ffs64(mask);
894 		val = (start & mask);
895 		addr = (start & ~mask) | (val & mask);
896 		do {
897 			bool used = false;
898 
899 			tmp_addr[5] = addr >> 0*8;
900 			tmp_addr[4] = addr >> 1*8;
901 			tmp_addr[3] = addr >> 2*8;
902 			tmp_addr[2] = addr >> 3*8;
903 			tmp_addr[1] = addr >> 4*8;
904 			tmp_addr[0] = addr >> 5*8;
905 
906 			val += inc;
907 
908 			list_for_each_entry(sdata, &local->interfaces, list) {
909 				if (memcmp(tmp_addr, sdata->vif.addr,
910 							ETH_ALEN) == 0) {
911 					used = true;
912 					break;
913 				}
914 			}
915 
916 			if (!used) {
917 				memcpy(dev->perm_addr, tmp_addr, ETH_ALEN);
918 				break;
919 			}
920 			addr = (start & ~mask) | (val & mask);
921 		} while (addr != start);
922 
923 		break;
924 	}
925 
926 	mutex_unlock(&local->iflist_mtx);
927 }
928 
929 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
930 		     struct net_device **new_dev, enum nl80211_iftype type,
931 		     struct vif_params *params)
932 {
933 	struct net_device *ndev;
934 	struct ieee80211_sub_if_data *sdata = NULL;
935 	int ret, i;
936 
937 	ASSERT_RTNL();
938 
939 	ndev = alloc_netdev_mq(sizeof(*sdata) + local->hw.vif_data_size,
940 			       name, ieee80211_if_setup, local->hw.queues);
941 	if (!ndev)
942 		return -ENOMEM;
943 	dev_net_set(ndev, wiphy_net(local->hw.wiphy));
944 
945 	ndev->needed_headroom = local->tx_headroom +
946 				4*6 /* four MAC addresses */
947 				+ 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
948 				+ 6 /* mesh */
949 				+ 8 /* rfc1042/bridge tunnel */
950 				- ETH_HLEN /* ethernet hard_header_len */
951 				+ IEEE80211_ENCRYPT_HEADROOM;
952 	ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
953 
954 	ret = dev_alloc_name(ndev, ndev->name);
955 	if (ret < 0)
956 		goto fail;
957 
958 	ieee80211_assign_perm_addr(local, ndev, type);
959 	memcpy(ndev->dev_addr, ndev->perm_addr, ETH_ALEN);
960 	SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
961 
962 	/* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
963 	sdata = netdev_priv(ndev);
964 	ndev->ieee80211_ptr = &sdata->wdev;
965 	memcpy(sdata->vif.addr, ndev->dev_addr, ETH_ALEN);
966 	memcpy(sdata->name, ndev->name, IFNAMSIZ);
967 
968 	/* initialise type-independent data */
969 	sdata->wdev.wiphy = local->hw.wiphy;
970 	sdata->local = local;
971 	sdata->dev = ndev;
972 
973 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
974 		skb_queue_head_init(&sdata->fragments[i].skb_list);
975 
976 	INIT_LIST_HEAD(&sdata->key_list);
977 
978 	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
979 		struct ieee80211_supported_band *sband;
980 		sband = local->hw.wiphy->bands[i];
981 		sdata->rc_rateidx_mask[i] =
982 			sband ? (1 << sband->n_bitrates) - 1 : 0;
983 	}
984 
985 	/* setup type-dependent data */
986 	ieee80211_setup_sdata(sdata, type);
987 
988 	if (params) {
989 		ndev->ieee80211_ptr->use_4addr = params->use_4addr;
990 		if (type == NL80211_IFTYPE_STATION)
991 			sdata->u.mgd.use_4addr = params->use_4addr;
992 	}
993 
994 	ret = register_netdevice(ndev);
995 	if (ret)
996 		goto fail;
997 
998 	if (ieee80211_vif_is_mesh(&sdata->vif) &&
999 	    params && params->mesh_id_len)
1000 		ieee80211_sdata_set_mesh_id(sdata,
1001 					    params->mesh_id_len,
1002 					    params->mesh_id);
1003 
1004 	mutex_lock(&local->iflist_mtx);
1005 	list_add_tail_rcu(&sdata->list, &local->interfaces);
1006 	mutex_unlock(&local->iflist_mtx);
1007 
1008 	if (new_dev)
1009 		*new_dev = ndev;
1010 
1011 	return 0;
1012 
1013  fail:
1014 	free_netdev(ndev);
1015 	return ret;
1016 }
1017 
1018 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
1019 {
1020 	ASSERT_RTNL();
1021 
1022 	mutex_lock(&sdata->local->iflist_mtx);
1023 	list_del_rcu(&sdata->list);
1024 	mutex_unlock(&sdata->local->iflist_mtx);
1025 
1026 	synchronize_rcu();
1027 	unregister_netdevice(sdata->dev);
1028 }
1029 
1030 /*
1031  * Remove all interfaces, may only be called at hardware unregistration
1032  * time because it doesn't do RCU-safe list removals.
1033  */
1034 void ieee80211_remove_interfaces(struct ieee80211_local *local)
1035 {
1036 	struct ieee80211_sub_if_data *sdata, *tmp;
1037 	LIST_HEAD(unreg_list);
1038 
1039 	ASSERT_RTNL();
1040 
1041 	mutex_lock(&local->iflist_mtx);
1042 	list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
1043 		list_del(&sdata->list);
1044 
1045 		unregister_netdevice_queue(sdata->dev, &unreg_list);
1046 	}
1047 	mutex_unlock(&local->iflist_mtx);
1048 	unregister_netdevice_many(&unreg_list);
1049 }
1050 
1051 static u32 ieee80211_idle_off(struct ieee80211_local *local,
1052 			      const char *reason)
1053 {
1054 	if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
1055 		return 0;
1056 
1057 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1058 	printk(KERN_DEBUG "%s: device no longer idle - %s\n",
1059 	       wiphy_name(local->hw.wiphy), reason);
1060 #endif
1061 
1062 	local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
1063 	return IEEE80211_CONF_CHANGE_IDLE;
1064 }
1065 
1066 static u32 ieee80211_idle_on(struct ieee80211_local *local)
1067 {
1068 	if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
1069 		return 0;
1070 
1071 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1072 	printk(KERN_DEBUG "%s: device now idle\n",
1073 	       wiphy_name(local->hw.wiphy));
1074 #endif
1075 
1076 	drv_flush(local, false);
1077 
1078 	local->hw.conf.flags |= IEEE80211_CONF_IDLE;
1079 	return IEEE80211_CONF_CHANGE_IDLE;
1080 }
1081 
1082 u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
1083 {
1084 	struct ieee80211_sub_if_data *sdata;
1085 	int count = 0;
1086 
1087 	if (!list_empty(&local->work_list))
1088 		return ieee80211_idle_off(local, "working");
1089 
1090 	if (local->scanning)
1091 		return ieee80211_idle_off(local, "scanning");
1092 
1093 	list_for_each_entry(sdata, &local->interfaces, list) {
1094 		if (!ieee80211_sdata_running(sdata))
1095 			continue;
1096 		/* do not count disabled managed interfaces */
1097 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1098 		    !sdata->u.mgd.associated)
1099 			continue;
1100 		/* do not count unused IBSS interfaces */
1101 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1102 		    !sdata->u.ibss.ssid_len)
1103 			continue;
1104 		/* count everything else */
1105 		count++;
1106 	}
1107 
1108 	if (!count)
1109 		return ieee80211_idle_on(local);
1110 	else
1111 		return ieee80211_idle_off(local, "in use");
1112 
1113 	return 0;
1114 }
1115 
1116 void ieee80211_recalc_idle(struct ieee80211_local *local)
1117 {
1118 	u32 chg;
1119 
1120 	mutex_lock(&local->iflist_mtx);
1121 	chg = __ieee80211_recalc_idle(local);
1122 	mutex_unlock(&local->iflist_mtx);
1123 	if (chg)
1124 		ieee80211_hw_config(local, chg);
1125 }
1126 
1127 static int netdev_notify(struct notifier_block *nb,
1128 			 unsigned long state,
1129 			 void *ndev)
1130 {
1131 	struct net_device *dev = ndev;
1132 	struct ieee80211_sub_if_data *sdata;
1133 
1134 	if (state != NETDEV_CHANGENAME)
1135 		return 0;
1136 
1137 	if (!dev->ieee80211_ptr || !dev->ieee80211_ptr->wiphy)
1138 		return 0;
1139 
1140 	if (dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
1141 		return 0;
1142 
1143 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1144 
1145 	memcpy(sdata->name, dev->name, IFNAMSIZ);
1146 
1147 	ieee80211_debugfs_rename_netdev(sdata);
1148 	return 0;
1149 }
1150 
1151 static struct notifier_block mac80211_netdev_notifier = {
1152 	.notifier_call = netdev_notify,
1153 };
1154 
1155 int ieee80211_iface_init(void)
1156 {
1157 	return register_netdevice_notifier(&mac80211_netdev_notifier);
1158 }
1159 
1160 void ieee80211_iface_exit(void)
1161 {
1162 	unregister_netdevice_notifier(&mac80211_netdev_notifier);
1163 }
1164