xref: /linux/net/mac80211/util.c (revision a33f32244d8550da8b4a26e277ce07d5c6d158b5)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * utilities for mac80211
12  */
13 
14 #include <net/mac80211.h>
15 #include <linux/netdevice.h>
16 #include <linux/types.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/etherdevice.h>
20 #include <linux/if_arp.h>
21 #include <linux/bitmap.h>
22 #include <linux/crc32.h>
23 #include <net/net_namespace.h>
24 #include <net/cfg80211.h>
25 #include <net/rtnetlink.h>
26 
27 #include "ieee80211_i.h"
28 #include "driver-ops.h"
29 #include "rate.h"
30 #include "mesh.h"
31 #include "wme.h"
32 #include "led.h"
33 #include "wep.h"
34 
35 /* privid for wiphys to determine whether they belong to us or not */
36 void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
37 
38 struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy)
39 {
40 	struct ieee80211_local *local;
41 	BUG_ON(!wiphy);
42 
43 	local = wiphy_priv(wiphy);
44 	return &local->hw;
45 }
46 EXPORT_SYMBOL(wiphy_to_ieee80211_hw);
47 
48 u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
49 			enum nl80211_iftype type)
50 {
51 	__le16 fc = hdr->frame_control;
52 
53 	 /* drop ACK/CTS frames and incorrect hdr len (ctrl) */
54 	if (len < 16)
55 		return NULL;
56 
57 	if (ieee80211_is_data(fc)) {
58 		if (len < 24) /* drop incorrect hdr len (data) */
59 			return NULL;
60 
61 		if (ieee80211_has_a4(fc))
62 			return NULL;
63 		if (ieee80211_has_tods(fc))
64 			return hdr->addr1;
65 		if (ieee80211_has_fromds(fc))
66 			return hdr->addr2;
67 
68 		return hdr->addr3;
69 	}
70 
71 	if (ieee80211_is_mgmt(fc)) {
72 		if (len < 24) /* drop incorrect hdr len (mgmt) */
73 			return NULL;
74 		return hdr->addr3;
75 	}
76 
77 	if (ieee80211_is_ctl(fc)) {
78 		if(ieee80211_is_pspoll(fc))
79 			return hdr->addr1;
80 
81 		if (ieee80211_is_back_req(fc)) {
82 			switch (type) {
83 			case NL80211_IFTYPE_STATION:
84 				return hdr->addr2;
85 			case NL80211_IFTYPE_AP:
86 			case NL80211_IFTYPE_AP_VLAN:
87 				return hdr->addr1;
88 			default:
89 				break; /* fall through to the return */
90 			}
91 		}
92 	}
93 
94 	return NULL;
95 }
96 
97 void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)
98 {
99 	struct sk_buff *skb = tx->skb;
100 	struct ieee80211_hdr *hdr;
101 
102 	do {
103 		hdr = (struct ieee80211_hdr *) skb->data;
104 		hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
105 	} while ((skb = skb->next));
106 }
107 
108 int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
109 			     int rate, int erp, int short_preamble)
110 {
111 	int dur;
112 
113 	/* calculate duration (in microseconds, rounded up to next higher
114 	 * integer if it includes a fractional microsecond) to send frame of
115 	 * len bytes (does not include FCS) at the given rate. Duration will
116 	 * also include SIFS.
117 	 *
118 	 * rate is in 100 kbps, so divident is multiplied by 10 in the
119 	 * DIV_ROUND_UP() operations.
120 	 */
121 
122 	if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ || erp) {
123 		/*
124 		 * OFDM:
125 		 *
126 		 * N_DBPS = DATARATE x 4
127 		 * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
128 		 *	(16 = SIGNAL time, 6 = tail bits)
129 		 * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
130 		 *
131 		 * T_SYM = 4 usec
132 		 * 802.11a - 17.5.2: aSIFSTime = 16 usec
133 		 * 802.11g - 19.8.4: aSIFSTime = 10 usec +
134 		 *	signal ext = 6 usec
135 		 */
136 		dur = 16; /* SIFS + signal ext */
137 		dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */
138 		dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
139 		dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10,
140 					4 * rate); /* T_SYM x N_SYM */
141 	} else {
142 		/*
143 		 * 802.11b or 802.11g with 802.11b compatibility:
144 		 * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
145 		 * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
146 		 *
147 		 * 802.11 (DS): 15.3.3, 802.11b: 18.3.4
148 		 * aSIFSTime = 10 usec
149 		 * aPreambleLength = 144 usec or 72 usec with short preamble
150 		 * aPLCPHeaderLength = 48 usec or 24 usec with short preamble
151 		 */
152 		dur = 10; /* aSIFSTime = 10 usec */
153 		dur += short_preamble ? (72 + 24) : (144 + 48);
154 
155 		dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate);
156 	}
157 
158 	return dur;
159 }
160 
161 /* Exported duration function for driver use */
162 __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
163 					struct ieee80211_vif *vif,
164 					size_t frame_len,
165 					struct ieee80211_rate *rate)
166 {
167 	struct ieee80211_local *local = hw_to_local(hw);
168 	struct ieee80211_sub_if_data *sdata;
169 	u16 dur;
170 	int erp;
171 	bool short_preamble = false;
172 
173 	erp = 0;
174 	if (vif) {
175 		sdata = vif_to_sdata(vif);
176 		short_preamble = sdata->vif.bss_conf.use_short_preamble;
177 		if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
178 			erp = rate->flags & IEEE80211_RATE_ERP_G;
179 	}
180 
181 	dur = ieee80211_frame_duration(local, frame_len, rate->bitrate, erp,
182 				       short_preamble);
183 
184 	return cpu_to_le16(dur);
185 }
186 EXPORT_SYMBOL(ieee80211_generic_frame_duration);
187 
188 __le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
189 			      struct ieee80211_vif *vif, size_t frame_len,
190 			      const struct ieee80211_tx_info *frame_txctl)
191 {
192 	struct ieee80211_local *local = hw_to_local(hw);
193 	struct ieee80211_rate *rate;
194 	struct ieee80211_sub_if_data *sdata;
195 	bool short_preamble;
196 	int erp;
197 	u16 dur;
198 	struct ieee80211_supported_band *sband;
199 
200 	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
201 
202 	short_preamble = false;
203 
204 	rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
205 
206 	erp = 0;
207 	if (vif) {
208 		sdata = vif_to_sdata(vif);
209 		short_preamble = sdata->vif.bss_conf.use_short_preamble;
210 		if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
211 			erp = rate->flags & IEEE80211_RATE_ERP_G;
212 	}
213 
214 	/* CTS duration */
215 	dur = ieee80211_frame_duration(local, 10, rate->bitrate,
216 				       erp, short_preamble);
217 	/* Data frame duration */
218 	dur += ieee80211_frame_duration(local, frame_len, rate->bitrate,
219 					erp, short_preamble);
220 	/* ACK duration */
221 	dur += ieee80211_frame_duration(local, 10, rate->bitrate,
222 					erp, short_preamble);
223 
224 	return cpu_to_le16(dur);
225 }
226 EXPORT_SYMBOL(ieee80211_rts_duration);
227 
228 __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
229 				    struct ieee80211_vif *vif,
230 				    size_t frame_len,
231 				    const struct ieee80211_tx_info *frame_txctl)
232 {
233 	struct ieee80211_local *local = hw_to_local(hw);
234 	struct ieee80211_rate *rate;
235 	struct ieee80211_sub_if_data *sdata;
236 	bool short_preamble;
237 	int erp;
238 	u16 dur;
239 	struct ieee80211_supported_band *sband;
240 
241 	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
242 
243 	short_preamble = false;
244 
245 	rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
246 	erp = 0;
247 	if (vif) {
248 		sdata = vif_to_sdata(vif);
249 		short_preamble = sdata->vif.bss_conf.use_short_preamble;
250 		if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
251 			erp = rate->flags & IEEE80211_RATE_ERP_G;
252 	}
253 
254 	/* Data frame duration */
255 	dur = ieee80211_frame_duration(local, frame_len, rate->bitrate,
256 				       erp, short_preamble);
257 	if (!(frame_txctl->flags & IEEE80211_TX_CTL_NO_ACK)) {
258 		/* ACK duration */
259 		dur += ieee80211_frame_duration(local, 10, rate->bitrate,
260 						erp, short_preamble);
261 	}
262 
263 	return cpu_to_le16(dur);
264 }
265 EXPORT_SYMBOL(ieee80211_ctstoself_duration);
266 
267 static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue,
268 				   enum queue_stop_reason reason)
269 {
270 	struct ieee80211_local *local = hw_to_local(hw);
271 	struct ieee80211_sub_if_data *sdata;
272 
273 	if (WARN_ON(queue >= hw->queues))
274 		return;
275 
276 	__clear_bit(reason, &local->queue_stop_reasons[queue]);
277 
278 	if (local->queue_stop_reasons[queue] != 0)
279 		/* someone still has this queue stopped */
280 		return;
281 
282 	if (skb_queue_empty(&local->pending[queue])) {
283 		rcu_read_lock();
284 		list_for_each_entry_rcu(sdata, &local->interfaces, list)
285 			netif_tx_wake_queue(netdev_get_tx_queue(sdata->dev, queue));
286 		rcu_read_unlock();
287 	} else
288 		tasklet_schedule(&local->tx_pending_tasklet);
289 }
290 
291 void ieee80211_wake_queue_by_reason(struct ieee80211_hw *hw, int queue,
292 				    enum queue_stop_reason reason)
293 {
294 	struct ieee80211_local *local = hw_to_local(hw);
295 	unsigned long flags;
296 
297 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
298 	__ieee80211_wake_queue(hw, queue, reason);
299 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
300 }
301 
302 void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
303 {
304 	ieee80211_wake_queue_by_reason(hw, queue,
305 				       IEEE80211_QUEUE_STOP_REASON_DRIVER);
306 }
307 EXPORT_SYMBOL(ieee80211_wake_queue);
308 
309 static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue,
310 				   enum queue_stop_reason reason)
311 {
312 	struct ieee80211_local *local = hw_to_local(hw);
313 	struct ieee80211_sub_if_data *sdata;
314 
315 	if (WARN_ON(queue >= hw->queues))
316 		return;
317 
318 	__set_bit(reason, &local->queue_stop_reasons[queue]);
319 
320 	rcu_read_lock();
321 	list_for_each_entry_rcu(sdata, &local->interfaces, list)
322 		netif_tx_stop_queue(netdev_get_tx_queue(sdata->dev, queue));
323 	rcu_read_unlock();
324 }
325 
326 void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue,
327 				    enum queue_stop_reason reason)
328 {
329 	struct ieee80211_local *local = hw_to_local(hw);
330 	unsigned long flags;
331 
332 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
333 	__ieee80211_stop_queue(hw, queue, reason);
334 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
335 }
336 
337 void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
338 {
339 	ieee80211_stop_queue_by_reason(hw, queue,
340 				       IEEE80211_QUEUE_STOP_REASON_DRIVER);
341 }
342 EXPORT_SYMBOL(ieee80211_stop_queue);
343 
344 void ieee80211_add_pending_skb(struct ieee80211_local *local,
345 			       struct sk_buff *skb)
346 {
347 	struct ieee80211_hw *hw = &local->hw;
348 	unsigned long flags;
349 	int queue = skb_get_queue_mapping(skb);
350 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
351 
352 	if (WARN_ON(!info->control.vif)) {
353 		kfree_skb(skb);
354 		return;
355 	}
356 
357 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
358 	__ieee80211_stop_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
359 	__skb_queue_tail(&local->pending[queue], skb);
360 	__ieee80211_wake_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
361 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
362 }
363 
364 int ieee80211_add_pending_skbs(struct ieee80211_local *local,
365 			       struct sk_buff_head *skbs)
366 {
367 	struct ieee80211_hw *hw = &local->hw;
368 	struct sk_buff *skb;
369 	unsigned long flags;
370 	int queue, ret = 0, i;
371 
372 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
373 	for (i = 0; i < hw->queues; i++)
374 		__ieee80211_stop_queue(hw, i,
375 			IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
376 
377 	while ((skb = skb_dequeue(skbs))) {
378 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
379 
380 		if (WARN_ON(!info->control.vif)) {
381 			kfree_skb(skb);
382 			continue;
383 		}
384 
385 		ret++;
386 		queue = skb_get_queue_mapping(skb);
387 		__skb_queue_tail(&local->pending[queue], skb);
388 	}
389 
390 	for (i = 0; i < hw->queues; i++)
391 		__ieee80211_wake_queue(hw, i,
392 			IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
393 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
394 
395 	return ret;
396 }
397 
398 void ieee80211_stop_queues_by_reason(struct ieee80211_hw *hw,
399 				    enum queue_stop_reason reason)
400 {
401 	struct ieee80211_local *local = hw_to_local(hw);
402 	unsigned long flags;
403 	int i;
404 
405 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
406 
407 	for (i = 0; i < hw->queues; i++)
408 		__ieee80211_stop_queue(hw, i, reason);
409 
410 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
411 }
412 
413 void ieee80211_stop_queues(struct ieee80211_hw *hw)
414 {
415 	ieee80211_stop_queues_by_reason(hw,
416 					IEEE80211_QUEUE_STOP_REASON_DRIVER);
417 }
418 EXPORT_SYMBOL(ieee80211_stop_queues);
419 
420 int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue)
421 {
422 	struct ieee80211_local *local = hw_to_local(hw);
423 	unsigned long flags;
424 	int ret;
425 
426 	if (WARN_ON(queue >= hw->queues))
427 		return true;
428 
429 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
430 	ret = !!local->queue_stop_reasons[queue];
431 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
432 	return ret;
433 }
434 EXPORT_SYMBOL(ieee80211_queue_stopped);
435 
436 void ieee80211_wake_queues_by_reason(struct ieee80211_hw *hw,
437 				     enum queue_stop_reason reason)
438 {
439 	struct ieee80211_local *local = hw_to_local(hw);
440 	unsigned long flags;
441 	int i;
442 
443 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
444 
445 	for (i = 0; i < hw->queues; i++)
446 		__ieee80211_wake_queue(hw, i, reason);
447 
448 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
449 }
450 
451 void ieee80211_wake_queues(struct ieee80211_hw *hw)
452 {
453 	ieee80211_wake_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_DRIVER);
454 }
455 EXPORT_SYMBOL(ieee80211_wake_queues);
456 
457 void ieee80211_iterate_active_interfaces(
458 	struct ieee80211_hw *hw,
459 	void (*iterator)(void *data, u8 *mac,
460 			 struct ieee80211_vif *vif),
461 	void *data)
462 {
463 	struct ieee80211_local *local = hw_to_local(hw);
464 	struct ieee80211_sub_if_data *sdata;
465 
466 	mutex_lock(&local->iflist_mtx);
467 
468 	list_for_each_entry(sdata, &local->interfaces, list) {
469 		switch (sdata->vif.type) {
470 		case __NL80211_IFTYPE_AFTER_LAST:
471 		case NL80211_IFTYPE_UNSPECIFIED:
472 		case NL80211_IFTYPE_MONITOR:
473 		case NL80211_IFTYPE_AP_VLAN:
474 			continue;
475 		case NL80211_IFTYPE_AP:
476 		case NL80211_IFTYPE_STATION:
477 		case NL80211_IFTYPE_ADHOC:
478 		case NL80211_IFTYPE_WDS:
479 		case NL80211_IFTYPE_MESH_POINT:
480 			break;
481 		}
482 		if (ieee80211_sdata_running(sdata))
483 			iterator(data, sdata->vif.addr,
484 				 &sdata->vif);
485 	}
486 
487 	mutex_unlock(&local->iflist_mtx);
488 }
489 EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces);
490 
491 void ieee80211_iterate_active_interfaces_atomic(
492 	struct ieee80211_hw *hw,
493 	void (*iterator)(void *data, u8 *mac,
494 			 struct ieee80211_vif *vif),
495 	void *data)
496 {
497 	struct ieee80211_local *local = hw_to_local(hw);
498 	struct ieee80211_sub_if_data *sdata;
499 
500 	rcu_read_lock();
501 
502 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
503 		switch (sdata->vif.type) {
504 		case __NL80211_IFTYPE_AFTER_LAST:
505 		case NL80211_IFTYPE_UNSPECIFIED:
506 		case NL80211_IFTYPE_MONITOR:
507 		case NL80211_IFTYPE_AP_VLAN:
508 			continue;
509 		case NL80211_IFTYPE_AP:
510 		case NL80211_IFTYPE_STATION:
511 		case NL80211_IFTYPE_ADHOC:
512 		case NL80211_IFTYPE_WDS:
513 		case NL80211_IFTYPE_MESH_POINT:
514 			break;
515 		}
516 		if (ieee80211_sdata_running(sdata))
517 			iterator(data, sdata->vif.addr,
518 				 &sdata->vif);
519 	}
520 
521 	rcu_read_unlock();
522 }
523 EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces_atomic);
524 
525 /*
526  * Nothing should have been stuffed into the workqueue during
527  * the suspend->resume cycle. If this WARN is seen then there
528  * is a bug with either the driver suspend or something in
529  * mac80211 stuffing into the workqueue which we haven't yet
530  * cleared during mac80211's suspend cycle.
531  */
532 static bool ieee80211_can_queue_work(struct ieee80211_local *local)
533 {
534 	if (WARN(local->suspended && !local->resuming,
535 		 "queueing ieee80211 work while going to suspend\n"))
536 		return false;
537 
538 	return true;
539 }
540 
541 void ieee80211_queue_work(struct ieee80211_hw *hw, struct work_struct *work)
542 {
543 	struct ieee80211_local *local = hw_to_local(hw);
544 
545 	if (!ieee80211_can_queue_work(local))
546 		return;
547 
548 	queue_work(local->workqueue, work);
549 }
550 EXPORT_SYMBOL(ieee80211_queue_work);
551 
552 void ieee80211_queue_delayed_work(struct ieee80211_hw *hw,
553 				  struct delayed_work *dwork,
554 				  unsigned long delay)
555 {
556 	struct ieee80211_local *local = hw_to_local(hw);
557 
558 	if (!ieee80211_can_queue_work(local))
559 		return;
560 
561 	queue_delayed_work(local->workqueue, dwork, delay);
562 }
563 EXPORT_SYMBOL(ieee80211_queue_delayed_work);
564 
565 void ieee802_11_parse_elems(u8 *start, size_t len,
566 			    struct ieee802_11_elems *elems)
567 {
568 	ieee802_11_parse_elems_crc(start, len, elems, 0, 0);
569 }
570 
571 u32 ieee802_11_parse_elems_crc(u8 *start, size_t len,
572 			       struct ieee802_11_elems *elems,
573 			       u64 filter, u32 crc)
574 {
575 	size_t left = len;
576 	u8 *pos = start;
577 	bool calc_crc = filter != 0;
578 
579 	memset(elems, 0, sizeof(*elems));
580 	elems->ie_start = start;
581 	elems->total_len = len;
582 
583 	while (left >= 2) {
584 		u8 id, elen;
585 
586 		id = *pos++;
587 		elen = *pos++;
588 		left -= 2;
589 
590 		if (elen > left)
591 			break;
592 
593 		if (calc_crc && id < 64 && (filter & (1ULL << id)))
594 			crc = crc32_be(crc, pos - 2, elen + 2);
595 
596 		switch (id) {
597 		case WLAN_EID_SSID:
598 			elems->ssid = pos;
599 			elems->ssid_len = elen;
600 			break;
601 		case WLAN_EID_SUPP_RATES:
602 			elems->supp_rates = pos;
603 			elems->supp_rates_len = elen;
604 			break;
605 		case WLAN_EID_FH_PARAMS:
606 			elems->fh_params = pos;
607 			elems->fh_params_len = elen;
608 			break;
609 		case WLAN_EID_DS_PARAMS:
610 			elems->ds_params = pos;
611 			elems->ds_params_len = elen;
612 			break;
613 		case WLAN_EID_CF_PARAMS:
614 			elems->cf_params = pos;
615 			elems->cf_params_len = elen;
616 			break;
617 		case WLAN_EID_TIM:
618 			if (elen >= sizeof(struct ieee80211_tim_ie)) {
619 				elems->tim = (void *)pos;
620 				elems->tim_len = elen;
621 			}
622 			break;
623 		case WLAN_EID_IBSS_PARAMS:
624 			elems->ibss_params = pos;
625 			elems->ibss_params_len = elen;
626 			break;
627 		case WLAN_EID_CHALLENGE:
628 			elems->challenge = pos;
629 			elems->challenge_len = elen;
630 			break;
631 		case WLAN_EID_VENDOR_SPECIFIC:
632 			if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 &&
633 			    pos[2] == 0xf2) {
634 				/* Microsoft OUI (00:50:F2) */
635 
636 				if (calc_crc)
637 					crc = crc32_be(crc, pos - 2, elen + 2);
638 
639 				if (pos[3] == 1) {
640 					/* OUI Type 1 - WPA IE */
641 					elems->wpa = pos;
642 					elems->wpa_len = elen;
643 				} else if (elen >= 5 && pos[3] == 2) {
644 					/* OUI Type 2 - WMM IE */
645 					if (pos[4] == 0) {
646 						elems->wmm_info = pos;
647 						elems->wmm_info_len = elen;
648 					} else if (pos[4] == 1) {
649 						elems->wmm_param = pos;
650 						elems->wmm_param_len = elen;
651 					}
652 				}
653 			}
654 			break;
655 		case WLAN_EID_RSN:
656 			elems->rsn = pos;
657 			elems->rsn_len = elen;
658 			break;
659 		case WLAN_EID_ERP_INFO:
660 			elems->erp_info = pos;
661 			elems->erp_info_len = elen;
662 			break;
663 		case WLAN_EID_EXT_SUPP_RATES:
664 			elems->ext_supp_rates = pos;
665 			elems->ext_supp_rates_len = elen;
666 			break;
667 		case WLAN_EID_HT_CAPABILITY:
668 			if (elen >= sizeof(struct ieee80211_ht_cap))
669 				elems->ht_cap_elem = (void *)pos;
670 			break;
671 		case WLAN_EID_HT_INFORMATION:
672 			if (elen >= sizeof(struct ieee80211_ht_info))
673 				elems->ht_info_elem = (void *)pos;
674 			break;
675 		case WLAN_EID_MESH_ID:
676 			elems->mesh_id = pos;
677 			elems->mesh_id_len = elen;
678 			break;
679 		case WLAN_EID_MESH_CONFIG:
680 			if (elen >= sizeof(struct ieee80211_meshconf_ie))
681 				elems->mesh_config = (void *)pos;
682 			break;
683 		case WLAN_EID_PEER_LINK:
684 			elems->peer_link = pos;
685 			elems->peer_link_len = elen;
686 			break;
687 		case WLAN_EID_PREQ:
688 			elems->preq = pos;
689 			elems->preq_len = elen;
690 			break;
691 		case WLAN_EID_PREP:
692 			elems->prep = pos;
693 			elems->prep_len = elen;
694 			break;
695 		case WLAN_EID_PERR:
696 			elems->perr = pos;
697 			elems->perr_len = elen;
698 			break;
699 		case WLAN_EID_RANN:
700 			if (elen >= sizeof(struct ieee80211_rann_ie))
701 				elems->rann = (void *)pos;
702 			break;
703 		case WLAN_EID_CHANNEL_SWITCH:
704 			elems->ch_switch_elem = pos;
705 			elems->ch_switch_elem_len = elen;
706 			break;
707 		case WLAN_EID_QUIET:
708 			if (!elems->quiet_elem) {
709 				elems->quiet_elem = pos;
710 				elems->quiet_elem_len = elen;
711 			}
712 			elems->num_of_quiet_elem++;
713 			break;
714 		case WLAN_EID_COUNTRY:
715 			elems->country_elem = pos;
716 			elems->country_elem_len = elen;
717 			break;
718 		case WLAN_EID_PWR_CONSTRAINT:
719 			elems->pwr_constr_elem = pos;
720 			elems->pwr_constr_elem_len = elen;
721 			break;
722 		case WLAN_EID_TIMEOUT_INTERVAL:
723 			elems->timeout_int = pos;
724 			elems->timeout_int_len = elen;
725 			break;
726 		default:
727 			break;
728 		}
729 
730 		left -= elen;
731 		pos += elen;
732 	}
733 
734 	return crc;
735 }
736 
737 void ieee80211_set_wmm_default(struct ieee80211_sub_if_data *sdata)
738 {
739 	struct ieee80211_local *local = sdata->local;
740 	struct ieee80211_tx_queue_params qparam;
741 	int queue;
742 	bool use_11b;
743 	int aCWmin, aCWmax;
744 
745 	if (!local->ops->conf_tx)
746 		return;
747 
748 	memset(&qparam, 0, sizeof(qparam));
749 
750 	use_11b = (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ) &&
751 		 !(sdata->flags & IEEE80211_SDATA_OPERATING_GMODE);
752 
753 	for (queue = 0; queue < local_to_hw(local)->queues; queue++) {
754 		/* Set defaults according to 802.11-2007 Table 7-37 */
755 		aCWmax = 1023;
756 		if (use_11b)
757 			aCWmin = 31;
758 		else
759 			aCWmin = 15;
760 
761 		switch (queue) {
762 		case 3: /* AC_BK */
763 			qparam.cw_max = aCWmax;
764 			qparam.cw_min = aCWmin;
765 			qparam.txop = 0;
766 			qparam.aifs = 7;
767 			break;
768 		default: /* never happens but let's not leave undefined */
769 		case 2: /* AC_BE */
770 			qparam.cw_max = aCWmax;
771 			qparam.cw_min = aCWmin;
772 			qparam.txop = 0;
773 			qparam.aifs = 3;
774 			break;
775 		case 1: /* AC_VI */
776 			qparam.cw_max = aCWmin;
777 			qparam.cw_min = (aCWmin + 1) / 2 - 1;
778 			if (use_11b)
779 				qparam.txop = 6016/32;
780 			else
781 				qparam.txop = 3008/32;
782 			qparam.aifs = 2;
783 			break;
784 		case 0: /* AC_VO */
785 			qparam.cw_max = (aCWmin + 1) / 2 - 1;
786 			qparam.cw_min = (aCWmin + 1) / 4 - 1;
787 			if (use_11b)
788 				qparam.txop = 3264/32;
789 			else
790 				qparam.txop = 1504/32;
791 			qparam.aifs = 2;
792 			break;
793 		}
794 
795 		qparam.uapsd = false;
796 
797 		drv_conf_tx(local, queue, &qparam);
798 	}
799 }
800 
801 void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata,
802 				  const size_t supp_rates_len,
803 				  const u8 *supp_rates)
804 {
805 	struct ieee80211_local *local = sdata->local;
806 	int i, have_higher_than_11mbit = 0;
807 
808 	/* cf. IEEE 802.11 9.2.12 */
809 	for (i = 0; i < supp_rates_len; i++)
810 		if ((supp_rates[i] & 0x7f) * 5 > 110)
811 			have_higher_than_11mbit = 1;
812 
813 	if (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ &&
814 	    have_higher_than_11mbit)
815 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
816 	else
817 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
818 
819 	ieee80211_set_wmm_default(sdata);
820 }
821 
822 u32 ieee80211_mandatory_rates(struct ieee80211_local *local,
823 			      enum ieee80211_band band)
824 {
825 	struct ieee80211_supported_band *sband;
826 	struct ieee80211_rate *bitrates;
827 	u32 mandatory_rates;
828 	enum ieee80211_rate_flags mandatory_flag;
829 	int i;
830 
831 	sband = local->hw.wiphy->bands[band];
832 	if (!sband) {
833 		WARN_ON(1);
834 		sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
835 	}
836 
837 	if (band == IEEE80211_BAND_2GHZ)
838 		mandatory_flag = IEEE80211_RATE_MANDATORY_B;
839 	else
840 		mandatory_flag = IEEE80211_RATE_MANDATORY_A;
841 
842 	bitrates = sband->bitrates;
843 	mandatory_rates = 0;
844 	for (i = 0; i < sband->n_bitrates; i++)
845 		if (bitrates[i].flags & mandatory_flag)
846 			mandatory_rates |= BIT(i);
847 	return mandatory_rates;
848 }
849 
850 void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
851 			 u16 transaction, u16 auth_alg,
852 			 u8 *extra, size_t extra_len, const u8 *bssid,
853 			 const u8 *key, u8 key_len, u8 key_idx)
854 {
855 	struct ieee80211_local *local = sdata->local;
856 	struct sk_buff *skb;
857 	struct ieee80211_mgmt *mgmt;
858 	int err;
859 
860 	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
861 			    sizeof(*mgmt) + 6 + extra_len);
862 	if (!skb) {
863 		printk(KERN_DEBUG "%s: failed to allocate buffer for auth "
864 		       "frame\n", sdata->name);
865 		return;
866 	}
867 	skb_reserve(skb, local->hw.extra_tx_headroom);
868 
869 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + 6);
870 	memset(mgmt, 0, 24 + 6);
871 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
872 					  IEEE80211_STYPE_AUTH);
873 	memcpy(mgmt->da, bssid, ETH_ALEN);
874 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
875 	memcpy(mgmt->bssid, bssid, ETH_ALEN);
876 	mgmt->u.auth.auth_alg = cpu_to_le16(auth_alg);
877 	mgmt->u.auth.auth_transaction = cpu_to_le16(transaction);
878 	mgmt->u.auth.status_code = cpu_to_le16(0);
879 	if (extra)
880 		memcpy(skb_put(skb, extra_len), extra, extra_len);
881 
882 	if (auth_alg == WLAN_AUTH_SHARED_KEY && transaction == 3) {
883 		mgmt->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
884 		err = ieee80211_wep_encrypt(local, skb, key, key_len, key_idx);
885 		WARN_ON(err);
886 	}
887 
888 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
889 	ieee80211_tx_skb(sdata, skb);
890 }
891 
892 int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
893 			     const u8 *ie, size_t ie_len,
894 			     enum ieee80211_band band)
895 {
896 	struct ieee80211_supported_band *sband;
897 	u8 *pos;
898 	size_t offset = 0, noffset;
899 	int supp_rates_len, i;
900 
901 	sband = local->hw.wiphy->bands[band];
902 
903 	pos = buffer;
904 
905 	supp_rates_len = min_t(int, sband->n_bitrates, 8);
906 
907 	*pos++ = WLAN_EID_SUPP_RATES;
908 	*pos++ = supp_rates_len;
909 
910 	for (i = 0; i < supp_rates_len; i++) {
911 		int rate = sband->bitrates[i].bitrate;
912 		*pos++ = (u8) (rate / 5);
913 	}
914 
915 	/* insert "request information" if in custom IEs */
916 	if (ie && ie_len) {
917 		static const u8 before_extrates[] = {
918 			WLAN_EID_SSID,
919 			WLAN_EID_SUPP_RATES,
920 			WLAN_EID_REQUEST,
921 		};
922 		noffset = ieee80211_ie_split(ie, ie_len,
923 					     before_extrates,
924 					     ARRAY_SIZE(before_extrates),
925 					     offset);
926 		memcpy(pos, ie + offset, noffset - offset);
927 		pos += noffset - offset;
928 		offset = noffset;
929 	}
930 
931 	if (sband->n_bitrates > i) {
932 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
933 		*pos++ = sband->n_bitrates - i;
934 
935 		for (; i < sband->n_bitrates; i++) {
936 			int rate = sband->bitrates[i].bitrate;
937 			*pos++ = (u8) (rate / 5);
938 		}
939 	}
940 
941 	/* insert custom IEs that go before HT */
942 	if (ie && ie_len) {
943 		static const u8 before_ht[] = {
944 			WLAN_EID_SSID,
945 			WLAN_EID_SUPP_RATES,
946 			WLAN_EID_REQUEST,
947 			WLAN_EID_EXT_SUPP_RATES,
948 			WLAN_EID_DS_PARAMS,
949 			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
950 		};
951 		noffset = ieee80211_ie_split(ie, ie_len,
952 					     before_ht, ARRAY_SIZE(before_ht),
953 					     offset);
954 		memcpy(pos, ie + offset, noffset - offset);
955 		pos += noffset - offset;
956 		offset = noffset;
957 	}
958 
959 	if (sband->ht_cap.ht_supported) {
960 		u16 cap = sband->ht_cap.cap;
961 		__le16 tmp;
962 
963 		if (ieee80211_disable_40mhz_24ghz &&
964 		    sband->band == IEEE80211_BAND_2GHZ) {
965 			cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
966 			cap &= ~IEEE80211_HT_CAP_SGI_40;
967 		}
968 
969 		*pos++ = WLAN_EID_HT_CAPABILITY;
970 		*pos++ = sizeof(struct ieee80211_ht_cap);
971 		memset(pos, 0, sizeof(struct ieee80211_ht_cap));
972 		tmp = cpu_to_le16(cap);
973 		memcpy(pos, &tmp, sizeof(u16));
974 		pos += sizeof(u16);
975 		*pos++ = sband->ht_cap.ampdu_factor |
976 			 (sband->ht_cap.ampdu_density <<
977 				IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
978 		memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
979 		pos += sizeof(sband->ht_cap.mcs);
980 		pos += 2 + 4 + 1; /* ext info, BF cap, antsel */
981 	}
982 
983 	/*
984 	 * If adding more here, adjust code in main.c
985 	 * that calculates local->scan_ies_len.
986 	 */
987 
988 	/* add any remaining custom IEs */
989 	if (ie && ie_len) {
990 		noffset = ie_len;
991 		memcpy(pos, ie + offset, noffset - offset);
992 		pos += noffset - offset;
993 	}
994 
995 	return pos - buffer;
996 }
997 
998 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
999 			      const u8 *ssid, size_t ssid_len,
1000 			      const u8 *ie, size_t ie_len)
1001 {
1002 	struct ieee80211_local *local = sdata->local;
1003 	struct sk_buff *skb;
1004 	struct ieee80211_mgmt *mgmt;
1005 	size_t buf_len;
1006 	u8 *buf;
1007 
1008 	/* FIXME: come up with a proper value */
1009 	buf = kmalloc(200 + ie_len, GFP_KERNEL);
1010 	if (!buf) {
1011 		printk(KERN_DEBUG "%s: failed to allocate temporary IE "
1012 		       "buffer\n", sdata->name);
1013 		return;
1014 	}
1015 
1016 	buf_len = ieee80211_build_preq_ies(local, buf, ie, ie_len,
1017 					   local->hw.conf.channel->band);
1018 
1019 	skb = ieee80211_probereq_get(&local->hw, &sdata->vif,
1020 				     ssid, ssid_len,
1021 				     buf, buf_len);
1022 
1023 	if (dst) {
1024 		mgmt = (struct ieee80211_mgmt *) skb->data;
1025 		memcpy(mgmt->da, dst, ETH_ALEN);
1026 		memcpy(mgmt->bssid, dst, ETH_ALEN);
1027 	}
1028 
1029 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1030 	ieee80211_tx_skb(sdata, skb);
1031 	kfree(buf);
1032 }
1033 
1034 u32 ieee80211_sta_get_rates(struct ieee80211_local *local,
1035 			    struct ieee802_11_elems *elems,
1036 			    enum ieee80211_band band)
1037 {
1038 	struct ieee80211_supported_band *sband;
1039 	struct ieee80211_rate *bitrates;
1040 	size_t num_rates;
1041 	u32 supp_rates;
1042 	int i, j;
1043 	sband = local->hw.wiphy->bands[band];
1044 
1045 	if (!sband) {
1046 		WARN_ON(1);
1047 		sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
1048 	}
1049 
1050 	bitrates = sband->bitrates;
1051 	num_rates = sband->n_bitrates;
1052 	supp_rates = 0;
1053 	for (i = 0; i < elems->supp_rates_len +
1054 		     elems->ext_supp_rates_len; i++) {
1055 		u8 rate = 0;
1056 		int own_rate;
1057 		if (i < elems->supp_rates_len)
1058 			rate = elems->supp_rates[i];
1059 		else if (elems->ext_supp_rates)
1060 			rate = elems->ext_supp_rates
1061 				[i - elems->supp_rates_len];
1062 		own_rate = 5 * (rate & 0x7f);
1063 		for (j = 0; j < num_rates; j++)
1064 			if (bitrates[j].bitrate == own_rate)
1065 				supp_rates |= BIT(j);
1066 	}
1067 	return supp_rates;
1068 }
1069 
1070 void ieee80211_stop_device(struct ieee80211_local *local)
1071 {
1072 	ieee80211_led_radio(local, false);
1073 
1074 	cancel_work_sync(&local->reconfig_filter);
1075 
1076 	flush_workqueue(local->workqueue);
1077 	drv_stop(local);
1078 }
1079 
1080 int ieee80211_reconfig(struct ieee80211_local *local)
1081 {
1082 	struct ieee80211_hw *hw = &local->hw;
1083 	struct ieee80211_sub_if_data *sdata;
1084 	struct sta_info *sta;
1085 	int res;
1086 
1087 	if (local->suspended)
1088 		local->resuming = true;
1089 
1090 	/* restart hardware */
1091 	if (local->open_count) {
1092 		/*
1093 		 * Upon resume hardware can sometimes be goofy due to
1094 		 * various platform / driver / bus issues, so restarting
1095 		 * the device may at times not work immediately. Propagate
1096 		 * the error.
1097 		 */
1098 		res = drv_start(local);
1099 		if (res) {
1100 			WARN(local->suspended, "Hardware became unavailable "
1101 			     "upon resume. This could be a software issue "
1102 			     "prior to suspend or a hardware issue.\n");
1103 			return res;
1104 		}
1105 
1106 		ieee80211_led_radio(local, true);
1107 	}
1108 
1109 	/* add interfaces */
1110 	list_for_each_entry(sdata, &local->interfaces, list) {
1111 		if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1112 		    sdata->vif.type != NL80211_IFTYPE_MONITOR &&
1113 		    ieee80211_sdata_running(sdata))
1114 			res = drv_add_interface(local, &sdata->vif);
1115 	}
1116 
1117 	/* add STAs back */
1118 	mutex_lock(&local->sta_mtx);
1119 	list_for_each_entry(sta, &local->sta_list, list) {
1120 		if (sta->uploaded) {
1121 			sdata = sta->sdata;
1122 			if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1123 				sdata = container_of(sdata->bss,
1124 					     struct ieee80211_sub_if_data,
1125 					     u.ap);
1126 
1127 			WARN_ON(drv_sta_add(local, sdata, &sta->sta));
1128 		}
1129 	}
1130 	mutex_unlock(&local->sta_mtx);
1131 
1132 	/* Clear Suspend state so that ADDBA requests can be processed */
1133 
1134 	rcu_read_lock();
1135 
1136 	if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
1137 		list_for_each_entry_rcu(sta, &local->sta_list, list) {
1138 			clear_sta_flags(sta, WLAN_STA_SUSPEND);
1139 		}
1140 	}
1141 
1142 	rcu_read_unlock();
1143 
1144 	/* setup RTS threshold */
1145 	drv_set_rts_threshold(local, hw->wiphy->rts_threshold);
1146 
1147 	/* reconfigure hardware */
1148 	ieee80211_hw_config(local, ~0);
1149 
1150 	ieee80211_configure_filter(local);
1151 
1152 	/* Finally also reconfigure all the BSS information */
1153 	list_for_each_entry(sdata, &local->interfaces, list) {
1154 		u32 changed = ~0;
1155 		if (!ieee80211_sdata_running(sdata))
1156 			continue;
1157 		switch (sdata->vif.type) {
1158 		case NL80211_IFTYPE_STATION:
1159 			/* disable beacon change bits */
1160 			changed &= ~(BSS_CHANGED_BEACON |
1161 				     BSS_CHANGED_BEACON_ENABLED);
1162 			/* fall through */
1163 		case NL80211_IFTYPE_ADHOC:
1164 		case NL80211_IFTYPE_AP:
1165 		case NL80211_IFTYPE_MESH_POINT:
1166 			ieee80211_bss_info_change_notify(sdata, changed);
1167 			break;
1168 		case NL80211_IFTYPE_WDS:
1169 			break;
1170 		case NL80211_IFTYPE_AP_VLAN:
1171 		case NL80211_IFTYPE_MONITOR:
1172 			/* ignore virtual */
1173 			break;
1174 		case NL80211_IFTYPE_UNSPECIFIED:
1175 		case __NL80211_IFTYPE_AFTER_LAST:
1176 			WARN_ON(1);
1177 			break;
1178 		}
1179 	}
1180 
1181 	rcu_read_lock();
1182 	if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
1183 		list_for_each_entry_rcu(sta, &local->sta_list, list) {
1184 			ieee80211_sta_tear_down_BA_sessions(sta);
1185 		}
1186 	}
1187 	rcu_read_unlock();
1188 
1189 	/* add back keys */
1190 	list_for_each_entry(sdata, &local->interfaces, list)
1191 		if (ieee80211_sdata_running(sdata))
1192 			ieee80211_enable_keys(sdata);
1193 
1194 	ieee80211_wake_queues_by_reason(hw,
1195 			IEEE80211_QUEUE_STOP_REASON_SUSPEND);
1196 
1197 	/*
1198 	 * If this is for hw restart things are still running.
1199 	 * We may want to change that later, however.
1200 	 */
1201 	if (!local->suspended)
1202 		return 0;
1203 
1204 #ifdef CONFIG_PM
1205 	/* first set suspended false, then resuming */
1206 	local->suspended = false;
1207 	mb();
1208 	local->resuming = false;
1209 
1210 	list_for_each_entry(sdata, &local->interfaces, list) {
1211 		switch(sdata->vif.type) {
1212 		case NL80211_IFTYPE_STATION:
1213 			ieee80211_sta_restart(sdata);
1214 			break;
1215 		case NL80211_IFTYPE_ADHOC:
1216 			ieee80211_ibss_restart(sdata);
1217 			break;
1218 		case NL80211_IFTYPE_MESH_POINT:
1219 			ieee80211_mesh_restart(sdata);
1220 			break;
1221 		default:
1222 			break;
1223 		}
1224 	}
1225 
1226 	add_timer(&local->sta_cleanup);
1227 
1228 	mutex_lock(&local->sta_mtx);
1229 	list_for_each_entry(sta, &local->sta_list, list)
1230 		mesh_plink_restart(sta);
1231 	mutex_unlock(&local->sta_mtx);
1232 #else
1233 	WARN_ON(1);
1234 #endif
1235 	return 0;
1236 }
1237 
1238 static int check_mgd_smps(struct ieee80211_if_managed *ifmgd,
1239 			  enum ieee80211_smps_mode *smps_mode)
1240 {
1241 	if (ifmgd->associated) {
1242 		*smps_mode = ifmgd->ap_smps;
1243 
1244 		if (*smps_mode == IEEE80211_SMPS_AUTOMATIC) {
1245 			if (ifmgd->powersave)
1246 				*smps_mode = IEEE80211_SMPS_DYNAMIC;
1247 			else
1248 				*smps_mode = IEEE80211_SMPS_OFF;
1249 		}
1250 
1251 		return 1;
1252 	}
1253 
1254 	return 0;
1255 }
1256 
1257 /* must hold iflist_mtx */
1258 void ieee80211_recalc_smps(struct ieee80211_local *local,
1259 			   struct ieee80211_sub_if_data *forsdata)
1260 {
1261 	struct ieee80211_sub_if_data *sdata;
1262 	enum ieee80211_smps_mode smps_mode = IEEE80211_SMPS_OFF;
1263 	int count = 0;
1264 
1265 	if (forsdata)
1266 		WARN_ON(!mutex_is_locked(&forsdata->u.mgd.mtx));
1267 
1268 	WARN_ON(!mutex_is_locked(&local->iflist_mtx));
1269 
1270 	/*
1271 	 * This function could be improved to handle multiple
1272 	 * interfaces better, but right now it makes any
1273 	 * non-station interfaces force SM PS to be turned
1274 	 * off. If there are multiple station interfaces it
1275 	 * could also use the best possible mode, e.g. if
1276 	 * one is in static and the other in dynamic then
1277 	 * dynamic is ok.
1278 	 */
1279 
1280 	list_for_each_entry(sdata, &local->interfaces, list) {
1281 		if (!netif_running(sdata->dev))
1282 			continue;
1283 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
1284 			goto set;
1285 		if (sdata != forsdata) {
1286 			/*
1287 			 * This nested is ok -- we are holding the iflist_mtx
1288 			 * so can't get here twice or so. But it's required
1289 			 * since normally we acquire it first and then the
1290 			 * iflist_mtx.
1291 			 */
1292 			mutex_lock_nested(&sdata->u.mgd.mtx, SINGLE_DEPTH_NESTING);
1293 			count += check_mgd_smps(&sdata->u.mgd, &smps_mode);
1294 			mutex_unlock(&sdata->u.mgd.mtx);
1295 		} else
1296 			count += check_mgd_smps(&sdata->u.mgd, &smps_mode);
1297 
1298 		if (count > 1) {
1299 			smps_mode = IEEE80211_SMPS_OFF;
1300 			break;
1301 		}
1302 	}
1303 
1304 	if (smps_mode == local->smps_mode)
1305 		return;
1306 
1307  set:
1308 	local->smps_mode = smps_mode;
1309 	/* changed flag is auto-detected for this */
1310 	ieee80211_hw_config(local, 0);
1311 }
1312 
1313 static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id)
1314 {
1315 	int i;
1316 
1317 	for (i = 0; i < n_ids; i++)
1318 		if (ids[i] == id)
1319 			return true;
1320 	return false;
1321 }
1322 
1323 /**
1324  * ieee80211_ie_split - split an IE buffer according to ordering
1325  *
1326  * @ies: the IE buffer
1327  * @ielen: the length of the IE buffer
1328  * @ids: an array with element IDs that are allowed before
1329  *	the split
1330  * @n_ids: the size of the element ID array
1331  * @offset: offset where to start splitting in the buffer
1332  *
1333  * This function splits an IE buffer by updating the @offset
1334  * variable to point to the location where the buffer should be
1335  * split.
1336  *
1337  * It assumes that the given IE buffer is well-formed, this
1338  * has to be guaranteed by the caller!
1339  *
1340  * It also assumes that the IEs in the buffer are ordered
1341  * correctly, if not the result of using this function will not
1342  * be ordered correctly either, i.e. it does no reordering.
1343  *
1344  * The function returns the offset where the next part of the
1345  * buffer starts, which may be @ielen if the entire (remainder)
1346  * of the buffer should be used.
1347  */
1348 size_t ieee80211_ie_split(const u8 *ies, size_t ielen,
1349 			  const u8 *ids, int n_ids, size_t offset)
1350 {
1351 	size_t pos = offset;
1352 
1353 	while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos]))
1354 		pos += 2 + ies[pos + 1];
1355 
1356 	return pos;
1357 }
1358 
1359 size_t ieee80211_ie_split_vendor(const u8 *ies, size_t ielen, size_t offset)
1360 {
1361 	size_t pos = offset;
1362 
1363 	while (pos < ielen && ies[pos] != WLAN_EID_VENDOR_SPECIFIC)
1364 		pos += 2 + ies[pos + 1];
1365 
1366 	return pos;
1367 }
1368