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drbd: Renamed overwrite_peer to primary_force
[linux-2.6/next.git] / net / mac80211 / util.c
blobc453226f06b2758377132ddb83e179c4c61ff921
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 tasklet_schedule(&local->tx_pending_tasklet);
284
285 rcu_read_lock();
286 list_for_each_entry_rcu(sdata, &local->interfaces, list)
287 netif_tx_wake_queue(netdev_get_tx_queue(sdata->dev, queue));
288 rcu_read_unlock();
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, "Harware became unavailable "
1101 "upon resume. This is 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 }
linux-next