xref: /openbmc/linux/net/mac80211/tx.c (revision 81d67439)
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  *
12  * Transmit and frame generation functions.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/skbuff.h>
18 #include <linux/etherdevice.h>
19 #include <linux/bitmap.h>
20 #include <linux/rcupdate.h>
21 #include <net/net_namespace.h>
22 #include <net/ieee80211_radiotap.h>
23 #include <net/cfg80211.h>
24 #include <net/mac80211.h>
25 #include <asm/unaligned.h>
26 
27 #include "ieee80211_i.h"
28 #include "driver-ops.h"
29 #include "led.h"
30 #include "mesh.h"
31 #include "wep.h"
32 #include "wpa.h"
33 #include "wme.h"
34 #include "rate.h"
35 
36 /* misc utils */
37 
38 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr,
39 				 int next_frag_len)
40 {
41 	int rate, mrate, erp, dur, i;
42 	struct ieee80211_rate *txrate;
43 	struct ieee80211_local *local = tx->local;
44 	struct ieee80211_supported_band *sband;
45 	struct ieee80211_hdr *hdr;
46 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
47 
48 	/* assume HW handles this */
49 	if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
50 		return 0;
51 
52 	/* uh huh? */
53 	if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
54 		return 0;
55 
56 	sband = local->hw.wiphy->bands[tx->channel->band];
57 	txrate = &sband->bitrates[info->control.rates[0].idx];
58 
59 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
60 
61 	/*
62 	 * data and mgmt (except PS Poll):
63 	 * - during CFP: 32768
64 	 * - during contention period:
65 	 *   if addr1 is group address: 0
66 	 *   if more fragments = 0 and addr1 is individual address: time to
67 	 *      transmit one ACK plus SIFS
68 	 *   if more fragments = 1 and addr1 is individual address: time to
69 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
70 	 *
71 	 * IEEE 802.11, 9.6:
72 	 * - control response frame (CTS or ACK) shall be transmitted using the
73 	 *   same rate as the immediately previous frame in the frame exchange
74 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
75 	 *   at the highest possible rate belonging to the PHY rates in the
76 	 *   BSSBasicRateSet
77 	 */
78 	hdr = (struct ieee80211_hdr *)tx->skb->data;
79 	if (ieee80211_is_ctl(hdr->frame_control)) {
80 		/* TODO: These control frames are not currently sent by
81 		 * mac80211, but should they be implemented, this function
82 		 * needs to be updated to support duration field calculation.
83 		 *
84 		 * RTS: time needed to transmit pending data/mgmt frame plus
85 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
86 		 * CTS: duration of immediately previous RTS minus time
87 		 *    required to transmit CTS and its SIFS
88 		 * ACK: 0 if immediately previous directed data/mgmt had
89 		 *    more=0, with more=1 duration in ACK frame is duration
90 		 *    from previous frame minus time needed to transmit ACK
91 		 *    and its SIFS
92 		 * PS Poll: BIT(15) | BIT(14) | aid
93 		 */
94 		return 0;
95 	}
96 
97 	/* data/mgmt */
98 	if (0 /* FIX: data/mgmt during CFP */)
99 		return cpu_to_le16(32768);
100 
101 	if (group_addr) /* Group address as the destination - no ACK */
102 		return 0;
103 
104 	/* Individual destination address:
105 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
106 	 * CTS and ACK frames shall be transmitted using the highest rate in
107 	 * basic rate set that is less than or equal to the rate of the
108 	 * immediately previous frame and that is using the same modulation
109 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
110 	 * the highest mandatory rate of the PHY that is less than or equal to
111 	 * the rate of the previous frame is used.
112 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
113 	 */
114 	rate = -1;
115 	/* use lowest available if everything fails */
116 	mrate = sband->bitrates[0].bitrate;
117 	for (i = 0; i < sband->n_bitrates; i++) {
118 		struct ieee80211_rate *r = &sband->bitrates[i];
119 
120 		if (r->bitrate > txrate->bitrate)
121 			break;
122 
123 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
124 			rate = r->bitrate;
125 
126 		switch (sband->band) {
127 		case IEEE80211_BAND_2GHZ: {
128 			u32 flag;
129 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
130 				flag = IEEE80211_RATE_MANDATORY_G;
131 			else
132 				flag = IEEE80211_RATE_MANDATORY_B;
133 			if (r->flags & flag)
134 				mrate = r->bitrate;
135 			break;
136 		}
137 		case IEEE80211_BAND_5GHZ:
138 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
139 				mrate = r->bitrate;
140 			break;
141 		case IEEE80211_NUM_BANDS:
142 			WARN_ON(1);
143 			break;
144 		}
145 	}
146 	if (rate == -1) {
147 		/* No matching basic rate found; use highest suitable mandatory
148 		 * PHY rate */
149 		rate = mrate;
150 	}
151 
152 	/* Time needed to transmit ACK
153 	 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
154 	 * to closest integer */
155 
156 	dur = ieee80211_frame_duration(local, 10, rate, erp,
157 				tx->sdata->vif.bss_conf.use_short_preamble);
158 
159 	if (next_frag_len) {
160 		/* Frame is fragmented: duration increases with time needed to
161 		 * transmit next fragment plus ACK and 2 x SIFS. */
162 		dur *= 2; /* ACK + SIFS */
163 		/* next fragment */
164 		dur += ieee80211_frame_duration(local, next_frag_len,
165 				txrate->bitrate, erp,
166 				tx->sdata->vif.bss_conf.use_short_preamble);
167 	}
168 
169 	return cpu_to_le16(dur);
170 }
171 
172 static inline int is_ieee80211_device(struct ieee80211_local *local,
173 				      struct net_device *dev)
174 {
175 	return local == wdev_priv(dev->ieee80211_ptr);
176 }
177 
178 /* tx handlers */
179 static ieee80211_tx_result debug_noinline
180 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
181 {
182 	struct ieee80211_local *local = tx->local;
183 	struct ieee80211_if_managed *ifmgd;
184 
185 	/* driver doesn't support power save */
186 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
187 		return TX_CONTINUE;
188 
189 	/* hardware does dynamic power save */
190 	if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
191 		return TX_CONTINUE;
192 
193 	/* dynamic power save disabled */
194 	if (local->hw.conf.dynamic_ps_timeout <= 0)
195 		return TX_CONTINUE;
196 
197 	/* we are scanning, don't enable power save */
198 	if (local->scanning)
199 		return TX_CONTINUE;
200 
201 	if (!local->ps_sdata)
202 		return TX_CONTINUE;
203 
204 	/* No point if we're going to suspend */
205 	if (local->quiescing)
206 		return TX_CONTINUE;
207 
208 	/* dynamic ps is supported only in managed mode */
209 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
210 		return TX_CONTINUE;
211 
212 	ifmgd = &tx->sdata->u.mgd;
213 
214 	/*
215 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
216 	 * u-apsd enabled and the frame is in voip class. This effectively
217 	 * means that even if all access categories have u-apsd enabled, in
218 	 * practise u-apsd is only used with the voip ac. This is a
219 	 * workaround for the case when received voip class packets do not
220 	 * have correct qos tag for some reason, due the network or the
221 	 * peer application.
222 	 *
223 	 * Note: local->uapsd_queues access is racy here. If the value is
224 	 * changed via debugfs, user needs to reassociate manually to have
225 	 * everything in sync.
226 	 */
227 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED)
228 	    && (local->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO)
229 	    && skb_get_queue_mapping(tx->skb) == 0)
230 		return TX_CONTINUE;
231 
232 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
233 		ieee80211_stop_queues_by_reason(&local->hw,
234 						IEEE80211_QUEUE_STOP_REASON_PS);
235 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
236 		ieee80211_queue_work(&local->hw,
237 				     &local->dynamic_ps_disable_work);
238 	}
239 
240 	/* Don't restart the timer if we're not disassociated */
241 	if (!ifmgd->associated)
242 		return TX_CONTINUE;
243 
244 	mod_timer(&local->dynamic_ps_timer, jiffies +
245 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
246 
247 	return TX_CONTINUE;
248 }
249 
250 static ieee80211_tx_result debug_noinline
251 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
252 {
253 
254 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
255 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
256 	u32 sta_flags;
257 
258 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
259 		return TX_CONTINUE;
260 
261 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
262 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
263 	    !ieee80211_is_probe_req(hdr->frame_control) &&
264 	    !ieee80211_is_nullfunc(hdr->frame_control))
265 		/*
266 		 * When software scanning only nullfunc frames (to notify
267 		 * the sleep state to the AP) and probe requests (for the
268 		 * active scan) are allowed, all other frames should not be
269 		 * sent and we should not get here, but if we do
270 		 * nonetheless, drop them to avoid sending them
271 		 * off-channel. See the link below and
272 		 * ieee80211_start_scan() for more.
273 		 *
274 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
275 		 */
276 		return TX_DROP;
277 
278 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
279 		return TX_CONTINUE;
280 
281 	if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
282 		return TX_CONTINUE;
283 
284 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
285 		return TX_CONTINUE;
286 
287 	sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
288 
289 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
290 		if (unlikely(!(sta_flags & WLAN_STA_ASSOC) &&
291 			     tx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
292 			     ieee80211_is_data(hdr->frame_control))) {
293 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
294 			printk(KERN_DEBUG "%s: dropped data frame to not "
295 			       "associated station %pM\n",
296 			       tx->sdata->name, hdr->addr1);
297 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
298 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
299 			return TX_DROP;
300 		}
301 	} else {
302 		if (unlikely(ieee80211_is_data(hdr->frame_control) &&
303 			     tx->local->num_sta == 0 &&
304 			     tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) {
305 			/*
306 			 * No associated STAs - no need to send multicast
307 			 * frames.
308 			 */
309 			return TX_DROP;
310 		}
311 		return TX_CONTINUE;
312 	}
313 
314 	return TX_CONTINUE;
315 }
316 
317 /* This function is called whenever the AP is about to exceed the maximum limit
318  * of buffered frames for power saving STAs. This situation should not really
319  * happen often during normal operation, so dropping the oldest buffered packet
320  * from each queue should be OK to make some room for new frames. */
321 static void purge_old_ps_buffers(struct ieee80211_local *local)
322 {
323 	int total = 0, purged = 0;
324 	struct sk_buff *skb;
325 	struct ieee80211_sub_if_data *sdata;
326 	struct sta_info *sta;
327 
328 	/*
329 	 * virtual interfaces are protected by RCU
330 	 */
331 	rcu_read_lock();
332 
333 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
334 		struct ieee80211_if_ap *ap;
335 		if (sdata->vif.type != NL80211_IFTYPE_AP)
336 			continue;
337 		ap = &sdata->u.ap;
338 		skb = skb_dequeue(&ap->ps_bc_buf);
339 		if (skb) {
340 			purged++;
341 			dev_kfree_skb(skb);
342 		}
343 		total += skb_queue_len(&ap->ps_bc_buf);
344 	}
345 
346 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
347 		skb = skb_dequeue(&sta->ps_tx_buf);
348 		if (skb) {
349 			purged++;
350 			dev_kfree_skb(skb);
351 		}
352 		total += skb_queue_len(&sta->ps_tx_buf);
353 	}
354 
355 	rcu_read_unlock();
356 
357 	local->total_ps_buffered = total;
358 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
359 	wiphy_debug(local->hw.wiphy, "PS buffers full - purged %d frames\n",
360 		    purged);
361 #endif
362 }
363 
364 static ieee80211_tx_result
365 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
366 {
367 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
368 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
369 
370 	/*
371 	 * broadcast/multicast frame
372 	 *
373 	 * If any of the associated stations is in power save mode,
374 	 * the frame is buffered to be sent after DTIM beacon frame.
375 	 * This is done either by the hardware or us.
376 	 */
377 
378 	/* powersaving STAs only in AP/VLAN mode */
379 	if (!tx->sdata->bss)
380 		return TX_CONTINUE;
381 
382 	/* no buffering for ordered frames */
383 	if (ieee80211_has_order(hdr->frame_control))
384 		return TX_CONTINUE;
385 
386 	/* no stations in PS mode */
387 	if (!atomic_read(&tx->sdata->bss->num_sta_ps))
388 		return TX_CONTINUE;
389 
390 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
391 
392 	/* device releases frame after DTIM beacon */
393 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
394 		return TX_CONTINUE;
395 
396 	/* buffered in mac80211 */
397 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
398 		purge_old_ps_buffers(tx->local);
399 
400 	if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
401 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
402 		if (net_ratelimit())
403 			printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n",
404 			       tx->sdata->name);
405 #endif
406 		dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
407 	} else
408 		tx->local->total_ps_buffered++;
409 
410 	skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
411 
412 	return TX_QUEUED;
413 }
414 
415 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
416 			     struct sk_buff *skb)
417 {
418 	if (!ieee80211_is_mgmt(fc))
419 		return 0;
420 
421 	if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP))
422 		return 0;
423 
424 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
425 					    skb->data))
426 		return 0;
427 
428 	return 1;
429 }
430 
431 static ieee80211_tx_result
432 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
433 {
434 	struct sta_info *sta = tx->sta;
435 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
436 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
437 	struct ieee80211_local *local = tx->local;
438 	u32 staflags;
439 
440 	if (unlikely(!sta ||
441 		     ieee80211_is_probe_resp(hdr->frame_control) ||
442 		     ieee80211_is_auth(hdr->frame_control) ||
443 		     ieee80211_is_assoc_resp(hdr->frame_control) ||
444 		     ieee80211_is_reassoc_resp(hdr->frame_control)))
445 		return TX_CONTINUE;
446 
447 	staflags = get_sta_flags(sta);
448 
449 	if (unlikely((staflags & (WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) &&
450 		     !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) {
451 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
452 		printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries "
453 		       "before %d)\n",
454 		       sta->sta.addr, sta->sta.aid,
455 		       skb_queue_len(&sta->ps_tx_buf));
456 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
457 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
458 			purge_old_ps_buffers(tx->local);
459 		if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
460 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
461 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
462 			if (net_ratelimit()) {
463 				printk(KERN_DEBUG "%s: STA %pM TX "
464 				       "buffer full - dropping oldest frame\n",
465 				       tx->sdata->name, sta->sta.addr);
466 			}
467 #endif
468 			dev_kfree_skb(old);
469 		} else
470 			tx->local->total_ps_buffered++;
471 
472 		/*
473 		 * Queue frame to be sent after STA wakes up/polls,
474 		 * but don't set the TIM bit if the driver is blocking
475 		 * wakeup or poll response transmissions anyway.
476 		 */
477 		if (skb_queue_empty(&sta->ps_tx_buf) &&
478 		    !(staflags & WLAN_STA_PS_DRIVER))
479 			sta_info_set_tim_bit(sta);
480 
481 		info->control.jiffies = jiffies;
482 		info->control.vif = &tx->sdata->vif;
483 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
484 		skb_queue_tail(&sta->ps_tx_buf, tx->skb);
485 
486 		if (!timer_pending(&local->sta_cleanup))
487 			mod_timer(&local->sta_cleanup,
488 				  round_jiffies(jiffies +
489 						STA_INFO_CLEANUP_INTERVAL));
490 
491 		return TX_QUEUED;
492 	}
493 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
494 	else if (unlikely(staflags & WLAN_STA_PS_STA)) {
495 		printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll "
496 		       "set -> send frame\n", tx->sdata->name,
497 		       sta->sta.addr);
498 	}
499 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
500 
501 	return TX_CONTINUE;
502 }
503 
504 static ieee80211_tx_result debug_noinline
505 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
506 {
507 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
508 		return TX_CONTINUE;
509 
510 	if (tx->flags & IEEE80211_TX_UNICAST)
511 		return ieee80211_tx_h_unicast_ps_buf(tx);
512 	else
513 		return ieee80211_tx_h_multicast_ps_buf(tx);
514 }
515 
516 static ieee80211_tx_result debug_noinline
517 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
518 {
519 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
520 
521 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
522 		     tx->sdata->control_port_no_encrypt))
523 		info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
524 
525 	return TX_CONTINUE;
526 }
527 
528 static ieee80211_tx_result debug_noinline
529 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
530 {
531 	struct ieee80211_key *key = NULL;
532 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
533 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
534 
535 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
536 		tx->key = NULL;
537 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
538 		tx->key = key;
539 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
540 		 is_multicast_ether_addr(hdr->addr1) &&
541 		 ieee80211_is_robust_mgmt_frame(hdr) &&
542 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
543 		tx->key = key;
544 	else if (is_multicast_ether_addr(hdr->addr1) &&
545 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
546 		tx->key = key;
547 	else if (!is_multicast_ether_addr(hdr->addr1) &&
548 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
549 		tx->key = key;
550 	else if (tx->sdata->drop_unencrypted &&
551 		 (tx->skb->protocol != tx->sdata->control_port_protocol) &&
552 		 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
553 		 (!ieee80211_is_robust_mgmt_frame(hdr) ||
554 		  (ieee80211_is_action(hdr->frame_control) &&
555 		   tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) {
556 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
557 		return TX_DROP;
558 	} else
559 		tx->key = NULL;
560 
561 	if (tx->key) {
562 		bool skip_hw = false;
563 
564 		tx->key->tx_rx_count++;
565 		/* TODO: add threshold stuff again */
566 
567 		switch (tx->key->conf.cipher) {
568 		case WLAN_CIPHER_SUITE_WEP40:
569 		case WLAN_CIPHER_SUITE_WEP104:
570 			if (ieee80211_is_auth(hdr->frame_control))
571 				break;
572 		case WLAN_CIPHER_SUITE_TKIP:
573 			if (!ieee80211_is_data_present(hdr->frame_control))
574 				tx->key = NULL;
575 			break;
576 		case WLAN_CIPHER_SUITE_CCMP:
577 			if (!ieee80211_is_data_present(hdr->frame_control) &&
578 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
579 					       tx->skb))
580 				tx->key = NULL;
581 			else
582 				skip_hw = (tx->key->conf.flags &
583 					   IEEE80211_KEY_FLAG_SW_MGMT) &&
584 					ieee80211_is_mgmt(hdr->frame_control);
585 			break;
586 		case WLAN_CIPHER_SUITE_AES_CMAC:
587 			if (!ieee80211_is_mgmt(hdr->frame_control))
588 				tx->key = NULL;
589 			break;
590 		}
591 
592 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED))
593 			return TX_DROP;
594 
595 		if (!skip_hw && tx->key &&
596 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
597 			info->control.hw_key = &tx->key->conf;
598 	}
599 
600 	return TX_CONTINUE;
601 }
602 
603 static ieee80211_tx_result debug_noinline
604 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
605 {
606 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
607 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
608 	struct ieee80211_supported_band *sband;
609 	struct ieee80211_rate *rate;
610 	int i;
611 	u32 len;
612 	bool inval = false, rts = false, short_preamble = false;
613 	struct ieee80211_tx_rate_control txrc;
614 	u32 sta_flags;
615 
616 	memset(&txrc, 0, sizeof(txrc));
617 
618 	sband = tx->local->hw.wiphy->bands[tx->channel->band];
619 
620 	len = min_t(u32, tx->skb->len + FCS_LEN,
621 			 tx->local->hw.wiphy->frag_threshold);
622 
623 	/* set up the tx rate control struct we give the RC algo */
624 	txrc.hw = local_to_hw(tx->local);
625 	txrc.sband = sband;
626 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
627 	txrc.skb = tx->skb;
628 	txrc.reported_rate.idx = -1;
629 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[tx->channel->band];
630 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
631 		txrc.max_rate_idx = -1;
632 	else
633 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
634 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
635 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
636 
637 	/* set up RTS protection if desired */
638 	if (len > tx->local->hw.wiphy->rts_threshold) {
639 		txrc.rts = rts = true;
640 	}
641 
642 	/*
643 	 * Use short preamble if the BSS can handle it, but not for
644 	 * management frames unless we know the receiver can handle
645 	 * that -- the management frame might be to a station that
646 	 * just wants a probe response.
647 	 */
648 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
649 	    (ieee80211_is_data(hdr->frame_control) ||
650 	     (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
651 		txrc.short_preamble = short_preamble = true;
652 
653 	sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
654 
655 	/*
656 	 * Lets not bother rate control if we're associated and cannot
657 	 * talk to the sta. This should not happen.
658 	 */
659 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) &&
660 		 (sta_flags & WLAN_STA_ASSOC) &&
661 		 !rate_usable_index_exists(sband, &tx->sta->sta),
662 		 "%s: Dropped data frame as no usable bitrate found while "
663 		 "scanning and associated. Target station: "
664 		 "%pM on %d GHz band\n",
665 		 tx->sdata->name, hdr->addr1,
666 		 tx->channel->band ? 5 : 2))
667 		return TX_DROP;
668 
669 	/*
670 	 * If we're associated with the sta at this point we know we can at
671 	 * least send the frame at the lowest bit rate.
672 	 */
673 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
674 
675 	if (unlikely(info->control.rates[0].idx < 0))
676 		return TX_DROP;
677 
678 	if (txrc.reported_rate.idx < 0) {
679 		txrc.reported_rate = info->control.rates[0];
680 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
681 			tx->sta->last_tx_rate = txrc.reported_rate;
682 	} else if (tx->sta)
683 		tx->sta->last_tx_rate = txrc.reported_rate;
684 
685 	if (unlikely(!info->control.rates[0].count))
686 		info->control.rates[0].count = 1;
687 
688 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
689 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
690 		info->control.rates[0].count = 1;
691 
692 	if (is_multicast_ether_addr(hdr->addr1)) {
693 		/*
694 		 * XXX: verify the rate is in the basic rateset
695 		 */
696 		return TX_CONTINUE;
697 	}
698 
699 	/*
700 	 * set up the RTS/CTS rate as the fastest basic rate
701 	 * that is not faster than the data rate
702 	 *
703 	 * XXX: Should this check all retry rates?
704 	 */
705 	if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
706 		s8 baserate = 0;
707 
708 		rate = &sband->bitrates[info->control.rates[0].idx];
709 
710 		for (i = 0; i < sband->n_bitrates; i++) {
711 			/* must be a basic rate */
712 			if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
713 				continue;
714 			/* must not be faster than the data rate */
715 			if (sband->bitrates[i].bitrate > rate->bitrate)
716 				continue;
717 			/* maximum */
718 			if (sband->bitrates[baserate].bitrate <
719 			     sband->bitrates[i].bitrate)
720 				baserate = i;
721 		}
722 
723 		info->control.rts_cts_rate_idx = baserate;
724 	}
725 
726 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
727 		/*
728 		 * make sure there's no valid rate following
729 		 * an invalid one, just in case drivers don't
730 		 * take the API seriously to stop at -1.
731 		 */
732 		if (inval) {
733 			info->control.rates[i].idx = -1;
734 			continue;
735 		}
736 		if (info->control.rates[i].idx < 0) {
737 			inval = true;
738 			continue;
739 		}
740 
741 		/*
742 		 * For now assume MCS is already set up correctly, this
743 		 * needs to be fixed.
744 		 */
745 		if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
746 			WARN_ON(info->control.rates[i].idx > 76);
747 			continue;
748 		}
749 
750 		/* set up RTS protection if desired */
751 		if (rts)
752 			info->control.rates[i].flags |=
753 				IEEE80211_TX_RC_USE_RTS_CTS;
754 
755 		/* RC is busted */
756 		if (WARN_ON_ONCE(info->control.rates[i].idx >=
757 				 sband->n_bitrates)) {
758 			info->control.rates[i].idx = -1;
759 			continue;
760 		}
761 
762 		rate = &sband->bitrates[info->control.rates[i].idx];
763 
764 		/* set up short preamble */
765 		if (short_preamble &&
766 		    rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
767 			info->control.rates[i].flags |=
768 				IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
769 
770 		/* set up G protection */
771 		if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
772 		    rate->flags & IEEE80211_RATE_ERP_G)
773 			info->control.rates[i].flags |=
774 				IEEE80211_TX_RC_USE_CTS_PROTECT;
775 	}
776 
777 	return TX_CONTINUE;
778 }
779 
780 static ieee80211_tx_result debug_noinline
781 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
782 {
783 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
784 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
785 	u16 *seq;
786 	u8 *qc;
787 	int tid;
788 
789 	/*
790 	 * Packet injection may want to control the sequence
791 	 * number, if we have no matching interface then we
792 	 * neither assign one ourselves nor ask the driver to.
793 	 */
794 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
795 		return TX_CONTINUE;
796 
797 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
798 		return TX_CONTINUE;
799 
800 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
801 		return TX_CONTINUE;
802 
803 	/*
804 	 * Anything but QoS data that has a sequence number field
805 	 * (is long enough) gets a sequence number from the global
806 	 * counter.
807 	 */
808 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
809 		/* driver should assign sequence number */
810 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
811 		/* for pure STA mode without beacons, we can do it */
812 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
813 		tx->sdata->sequence_number += 0x10;
814 		return TX_CONTINUE;
815 	}
816 
817 	/*
818 	 * This should be true for injected/management frames only, for
819 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
820 	 * above since they are not QoS-data frames.
821 	 */
822 	if (!tx->sta)
823 		return TX_CONTINUE;
824 
825 	/* include per-STA, per-TID sequence counter */
826 
827 	qc = ieee80211_get_qos_ctl(hdr);
828 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
829 	seq = &tx->sta->tid_seq[tid];
830 
831 	hdr->seq_ctrl = cpu_to_le16(*seq);
832 
833 	/* Increase the sequence number. */
834 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
835 
836 	return TX_CONTINUE;
837 }
838 
839 static int ieee80211_fragment(struct ieee80211_local *local,
840 			      struct sk_buff *skb, int hdrlen,
841 			      int frag_threshold)
842 {
843 	struct sk_buff *tail = skb, *tmp;
844 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
845 	int pos = hdrlen + per_fragm;
846 	int rem = skb->len - hdrlen - per_fragm;
847 
848 	if (WARN_ON(rem < 0))
849 		return -EINVAL;
850 
851 	while (rem) {
852 		int fraglen = per_fragm;
853 
854 		if (fraglen > rem)
855 			fraglen = rem;
856 		rem -= fraglen;
857 		tmp = dev_alloc_skb(local->tx_headroom +
858 				    frag_threshold +
859 				    IEEE80211_ENCRYPT_HEADROOM +
860 				    IEEE80211_ENCRYPT_TAILROOM);
861 		if (!tmp)
862 			return -ENOMEM;
863 		tail->next = tmp;
864 		tail = tmp;
865 		skb_reserve(tmp, local->tx_headroom +
866 				 IEEE80211_ENCRYPT_HEADROOM);
867 		/* copy control information */
868 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
869 		skb_copy_queue_mapping(tmp, skb);
870 		tmp->priority = skb->priority;
871 		tmp->dev = skb->dev;
872 
873 		/* copy header and data */
874 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
875 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
876 
877 		pos += fraglen;
878 	}
879 
880 	skb->len = hdrlen + per_fragm;
881 	return 0;
882 }
883 
884 static ieee80211_tx_result debug_noinline
885 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
886 {
887 	struct sk_buff *skb = tx->skb;
888 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
889 	struct ieee80211_hdr *hdr = (void *)skb->data;
890 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
891 	int hdrlen;
892 	int fragnum;
893 
894 	if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
895 		return TX_CONTINUE;
896 
897 	/*
898 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
899 	 * This scenario is handled in ieee80211_tx_prepare but extra
900 	 * caution taken here as fragmented ampdu may cause Tx stop.
901 	 */
902 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
903 		return TX_DROP;
904 
905 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
906 
907 	/* internal error, why is TX_FRAGMENTED set? */
908 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
909 		return TX_DROP;
910 
911 	/*
912 	 * Now fragment the frame. This will allocate all the fragments and
913 	 * chain them (using skb as the first fragment) to skb->next.
914 	 * During transmission, we will remove the successfully transmitted
915 	 * fragments from this list. When the low-level driver rejects one
916 	 * of the fragments then we will simply pretend to accept the skb
917 	 * but store it away as pending.
918 	 */
919 	if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
920 		return TX_DROP;
921 
922 	/* update duration/seq/flags of fragments */
923 	fragnum = 0;
924 	do {
925 		int next_len;
926 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
927 
928 		hdr = (void *)skb->data;
929 		info = IEEE80211_SKB_CB(skb);
930 
931 		if (skb->next) {
932 			hdr->frame_control |= morefrags;
933 			next_len = skb->next->len;
934 			/*
935 			 * No multi-rate retries for fragmented frames, that
936 			 * would completely throw off the NAV at other STAs.
937 			 */
938 			info->control.rates[1].idx = -1;
939 			info->control.rates[2].idx = -1;
940 			info->control.rates[3].idx = -1;
941 			info->control.rates[4].idx = -1;
942 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
943 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
944 		} else {
945 			hdr->frame_control &= ~morefrags;
946 			next_len = 0;
947 		}
948 		hdr->duration_id = ieee80211_duration(tx, 0, next_len);
949 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
950 		fragnum++;
951 	} while ((skb = skb->next));
952 
953 	return TX_CONTINUE;
954 }
955 
956 static ieee80211_tx_result debug_noinline
957 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
958 {
959 	struct sk_buff *skb = tx->skb;
960 
961 	if (!tx->sta)
962 		return TX_CONTINUE;
963 
964 	tx->sta->tx_packets++;
965 	do {
966 		tx->sta->tx_fragments++;
967 		tx->sta->tx_bytes += skb->len;
968 	} while ((skb = skb->next));
969 
970 	return TX_CONTINUE;
971 }
972 
973 static ieee80211_tx_result debug_noinline
974 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
975 {
976 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
977 
978 	if (!tx->key)
979 		return TX_CONTINUE;
980 
981 	switch (tx->key->conf.cipher) {
982 	case WLAN_CIPHER_SUITE_WEP40:
983 	case WLAN_CIPHER_SUITE_WEP104:
984 		return ieee80211_crypto_wep_encrypt(tx);
985 	case WLAN_CIPHER_SUITE_TKIP:
986 		return ieee80211_crypto_tkip_encrypt(tx);
987 	case WLAN_CIPHER_SUITE_CCMP:
988 		return ieee80211_crypto_ccmp_encrypt(tx);
989 	case WLAN_CIPHER_SUITE_AES_CMAC:
990 		return ieee80211_crypto_aes_cmac_encrypt(tx);
991 	default:
992 		/* handle hw-only algorithm */
993 		if (info->control.hw_key) {
994 			ieee80211_tx_set_protected(tx);
995 			return TX_CONTINUE;
996 		}
997 		break;
998 
999 	}
1000 
1001 	return TX_DROP;
1002 }
1003 
1004 static ieee80211_tx_result debug_noinline
1005 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1006 {
1007 	struct sk_buff *skb = tx->skb;
1008 	struct ieee80211_hdr *hdr;
1009 	int next_len;
1010 	bool group_addr;
1011 
1012 	do {
1013 		hdr = (void *) skb->data;
1014 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1015 			break; /* must not overwrite AID */
1016 		next_len = skb->next ? skb->next->len : 0;
1017 		group_addr = is_multicast_ether_addr(hdr->addr1);
1018 
1019 		hdr->duration_id =
1020 			ieee80211_duration(tx, group_addr, next_len);
1021 	} while ((skb = skb->next));
1022 
1023 	return TX_CONTINUE;
1024 }
1025 
1026 /* actual transmit path */
1027 
1028 /*
1029  * deal with packet injection down monitor interface
1030  * with Radiotap Header -- only called for monitor mode interface
1031  */
1032 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
1033 					  struct sk_buff *skb)
1034 {
1035 	/*
1036 	 * this is the moment to interpret and discard the radiotap header that
1037 	 * must be at the start of the packet injected in Monitor mode
1038 	 *
1039 	 * Need to take some care with endian-ness since radiotap
1040 	 * args are little-endian
1041 	 */
1042 
1043 	struct ieee80211_radiotap_iterator iterator;
1044 	struct ieee80211_radiotap_header *rthdr =
1045 		(struct ieee80211_radiotap_header *) skb->data;
1046 	bool hw_frag;
1047 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1048 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1049 						   NULL);
1050 
1051 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1052 	tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1053 
1054 	/* packet is fragmented in HW if we have a non-NULL driver callback */
1055 	hw_frag = (tx->local->ops->set_frag_threshold != NULL);
1056 
1057 	/*
1058 	 * for every radiotap entry that is present
1059 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1060 	 * entries present, or -EINVAL on error)
1061 	 */
1062 
1063 	while (!ret) {
1064 		ret = ieee80211_radiotap_iterator_next(&iterator);
1065 
1066 		if (ret)
1067 			continue;
1068 
1069 		/* see if this argument is something we can use */
1070 		switch (iterator.this_arg_index) {
1071 		/*
1072 		 * You must take care when dereferencing iterator.this_arg
1073 		 * for multibyte types... the pointer is not aligned.  Use
1074 		 * get_unaligned((type *)iterator.this_arg) to dereference
1075 		 * iterator.this_arg for type "type" safely on all arches.
1076 		*/
1077 		case IEEE80211_RADIOTAP_FLAGS:
1078 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1079 				/*
1080 				 * this indicates that the skb we have been
1081 				 * handed has the 32-bit FCS CRC at the end...
1082 				 * we should react to that by snipping it off
1083 				 * because it will be recomputed and added
1084 				 * on transmission
1085 				 */
1086 				if (skb->len < (iterator._max_length + FCS_LEN))
1087 					return false;
1088 
1089 				skb_trim(skb, skb->len - FCS_LEN);
1090 			}
1091 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1092 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1093 			if ((*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) &&
1094 								!hw_frag)
1095 				tx->flags |= IEEE80211_TX_FRAGMENTED;
1096 			break;
1097 
1098 		/*
1099 		 * Please update the file
1100 		 * Documentation/networking/mac80211-injection.txt
1101 		 * when parsing new fields here.
1102 		 */
1103 
1104 		default:
1105 			break;
1106 		}
1107 	}
1108 
1109 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1110 		return false;
1111 
1112 	/*
1113 	 * remove the radiotap header
1114 	 * iterator->_max_length was sanity-checked against
1115 	 * skb->len by iterator init
1116 	 */
1117 	skb_pull(skb, iterator._max_length);
1118 
1119 	return true;
1120 }
1121 
1122 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1123 				  struct sk_buff *skb,
1124 				  struct ieee80211_tx_info *info,
1125 				  struct tid_ampdu_tx *tid_tx,
1126 				  int tid)
1127 {
1128 	bool queued = false;
1129 
1130 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1131 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1132 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1133 		/*
1134 		 * nothing -- this aggregation session is being started
1135 		 * but that might still fail with the driver
1136 		 */
1137 	} else {
1138 		spin_lock(&tx->sta->lock);
1139 		/*
1140 		 * Need to re-check now, because we may get here
1141 		 *
1142 		 *  1) in the window during which the setup is actually
1143 		 *     already done, but not marked yet because not all
1144 		 *     packets are spliced over to the driver pending
1145 		 *     queue yet -- if this happened we acquire the lock
1146 		 *     either before or after the splice happens, but
1147 		 *     need to recheck which of these cases happened.
1148 		 *
1149 		 *  2) during session teardown, if the OPERATIONAL bit
1150 		 *     was cleared due to the teardown but the pointer
1151 		 *     hasn't been assigned NULL yet (or we loaded it
1152 		 *     before it was assigned) -- in this case it may
1153 		 *     now be NULL which means we should just let the
1154 		 *     packet pass through because splicing the frames
1155 		 *     back is already done.
1156 		 */
1157 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1158 
1159 		if (!tid_tx) {
1160 			/* do nothing, let packet pass through */
1161 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1162 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1163 		} else {
1164 			queued = true;
1165 			info->control.vif = &tx->sdata->vif;
1166 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1167 			__skb_queue_tail(&tid_tx->pending, skb);
1168 		}
1169 		spin_unlock(&tx->sta->lock);
1170 	}
1171 
1172 	return queued;
1173 }
1174 
1175 /*
1176  * initialises @tx
1177  */
1178 static ieee80211_tx_result
1179 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1180 		     struct ieee80211_tx_data *tx,
1181 		     struct sk_buff *skb)
1182 {
1183 	struct ieee80211_local *local = sdata->local;
1184 	struct ieee80211_hdr *hdr;
1185 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1186 	int hdrlen, tid;
1187 	u8 *qc;
1188 
1189 	memset(tx, 0, sizeof(*tx));
1190 	tx->skb = skb;
1191 	tx->local = local;
1192 	tx->sdata = sdata;
1193 	tx->channel = local->hw.conf.channel;
1194 	/*
1195 	 * Set this flag (used below to indicate "automatic fragmentation"),
1196 	 * it will be cleared/left by radiotap as desired.
1197 	 * Only valid when fragmentation is done by the stack.
1198 	 */
1199 	if (!local->ops->set_frag_threshold)
1200 		tx->flags |= IEEE80211_TX_FRAGMENTED;
1201 
1202 	/* process and remove the injection radiotap header */
1203 	if (unlikely(info->flags & IEEE80211_TX_INTFL_HAS_RADIOTAP)) {
1204 		if (!__ieee80211_parse_tx_radiotap(tx, skb))
1205 			return TX_DROP;
1206 
1207 		/*
1208 		 * __ieee80211_parse_tx_radiotap has now removed
1209 		 * the radiotap header that was present and pre-filled
1210 		 * 'tx' with tx control information.
1211 		 */
1212 		info->flags &= ~IEEE80211_TX_INTFL_HAS_RADIOTAP;
1213 	}
1214 
1215 	/*
1216 	 * If this flag is set to true anywhere, and we get here,
1217 	 * we are doing the needed processing, so remove the flag
1218 	 * now.
1219 	 */
1220 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1221 
1222 	hdr = (struct ieee80211_hdr *) skb->data;
1223 
1224 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1225 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1226 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1227 			return TX_DROP;
1228 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED) {
1229 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1230 	}
1231 	if (!tx->sta)
1232 		tx->sta = sta_info_get(sdata, hdr->addr1);
1233 
1234 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1235 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1236 		struct tid_ampdu_tx *tid_tx;
1237 
1238 		qc = ieee80211_get_qos_ctl(hdr);
1239 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1240 
1241 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1242 		if (tid_tx) {
1243 			bool queued;
1244 
1245 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1246 						       tid_tx, tid);
1247 
1248 			if (unlikely(queued))
1249 				return TX_QUEUED;
1250 		}
1251 	}
1252 
1253 	if (is_multicast_ether_addr(hdr->addr1)) {
1254 		tx->flags &= ~IEEE80211_TX_UNICAST;
1255 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1256 	} else {
1257 		tx->flags |= IEEE80211_TX_UNICAST;
1258 		if (unlikely(local->wifi_wme_noack_test))
1259 			info->flags |= IEEE80211_TX_CTL_NO_ACK;
1260 		else
1261 			info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1262 	}
1263 
1264 	if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1265 		if ((tx->flags & IEEE80211_TX_UNICAST) &&
1266 		    skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
1267 		    !(info->flags & IEEE80211_TX_CTL_AMPDU))
1268 			tx->flags |= IEEE80211_TX_FRAGMENTED;
1269 		else
1270 			tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1271 	}
1272 
1273 	if (!tx->sta)
1274 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1275 	else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1276 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1277 
1278 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1279 	if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1280 		u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1281 		tx->ethertype = (pos[0] << 8) | pos[1];
1282 	}
1283 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1284 
1285 	return TX_CONTINUE;
1286 }
1287 
1288 /*
1289  * Returns false if the frame couldn't be transmitted but was queued instead.
1290  */
1291 static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp,
1292 			   struct sta_info *sta, bool txpending)
1293 {
1294 	struct sk_buff *skb = *skbp, *next;
1295 	struct ieee80211_tx_info *info;
1296 	struct ieee80211_sub_if_data *sdata;
1297 	unsigned long flags;
1298 	int len;
1299 	bool fragm = false;
1300 
1301 	while (skb) {
1302 		int q = skb_get_queue_mapping(skb);
1303 		__le16 fc;
1304 
1305 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1306 		if (local->queue_stop_reasons[q] ||
1307 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1308 			/*
1309 			 * Since queue is stopped, queue up frames for later
1310 			 * transmission from the tx-pending tasklet when the
1311 			 * queue is woken again.
1312 			 */
1313 
1314 			do {
1315 				next = skb->next;
1316 				skb->next = NULL;
1317 				/*
1318 				 * NB: If txpending is true, next must already
1319 				 * be NULL since we must've gone through this
1320 				 * loop before already; therefore we can just
1321 				 * queue the frame to the head without worrying
1322 				 * about reordering of fragments.
1323 				 */
1324 				if (unlikely(txpending))
1325 					__skb_queue_head(&local->pending[q],
1326 							 skb);
1327 				else
1328 					__skb_queue_tail(&local->pending[q],
1329 							 skb);
1330 			} while ((skb = next));
1331 
1332 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1333 					       flags);
1334 			return false;
1335 		}
1336 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1337 
1338 		info = IEEE80211_SKB_CB(skb);
1339 
1340 		if (fragm)
1341 			info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1342 					 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1343 
1344 		next = skb->next;
1345 		len = skb->len;
1346 
1347 		if (next)
1348 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
1349 
1350 		sdata = vif_to_sdata(info->control.vif);
1351 
1352 		switch (sdata->vif.type) {
1353 		case NL80211_IFTYPE_MONITOR:
1354 			info->control.vif = NULL;
1355 			break;
1356 		case NL80211_IFTYPE_AP_VLAN:
1357 			info->control.vif = &container_of(sdata->bss,
1358 				struct ieee80211_sub_if_data, u.ap)->vif;
1359 			break;
1360 		default:
1361 			/* keep */
1362 			break;
1363 		}
1364 
1365 		if (sta && sta->uploaded)
1366 			info->control.sta = &sta->sta;
1367 		else
1368 			info->control.sta = NULL;
1369 
1370 		fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1371 		drv_tx(local, skb);
1372 
1373 		ieee80211_tpt_led_trig_tx(local, fc, len);
1374 		*skbp = skb = next;
1375 		ieee80211_led_tx(local, 1);
1376 		fragm = true;
1377 	}
1378 
1379 	return true;
1380 }
1381 
1382 /*
1383  * Invoke TX handlers, return 0 on success and non-zero if the
1384  * frame was dropped or queued.
1385  */
1386 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1387 {
1388 	struct sk_buff *skb = tx->skb;
1389 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1390 	ieee80211_tx_result res = TX_DROP;
1391 
1392 #define CALL_TXH(txh) \
1393 	do {				\
1394 		res = txh(tx);		\
1395 		if (res != TX_CONTINUE)	\
1396 			goto txh_done;	\
1397 	} while (0)
1398 
1399 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1400 	CALL_TXH(ieee80211_tx_h_check_assoc);
1401 	CALL_TXH(ieee80211_tx_h_ps_buf);
1402 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1403 	CALL_TXH(ieee80211_tx_h_select_key);
1404 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1405 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1406 
1407 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION))
1408 		goto txh_done;
1409 
1410 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1411 	CALL_TXH(ieee80211_tx_h_sequence);
1412 	CALL_TXH(ieee80211_tx_h_fragment);
1413 	/* handlers after fragment must be aware of tx info fragmentation! */
1414 	CALL_TXH(ieee80211_tx_h_stats);
1415 	CALL_TXH(ieee80211_tx_h_encrypt);
1416 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1417 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1418 #undef CALL_TXH
1419 
1420  txh_done:
1421 	if (unlikely(res == TX_DROP)) {
1422 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1423 		while (skb) {
1424 			struct sk_buff *next;
1425 
1426 			next = skb->next;
1427 			dev_kfree_skb(skb);
1428 			skb = next;
1429 		}
1430 		return -1;
1431 	} else if (unlikely(res == TX_QUEUED)) {
1432 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1433 		return -1;
1434 	}
1435 
1436 	return 0;
1437 }
1438 
1439 /*
1440  * Returns false if the frame couldn't be transmitted but was queued instead.
1441  */
1442 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1443 			 struct sk_buff *skb, bool txpending)
1444 {
1445 	struct ieee80211_local *local = sdata->local;
1446 	struct ieee80211_tx_data tx;
1447 	ieee80211_tx_result res_prepare;
1448 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1449 	bool result = true;
1450 
1451 	if (unlikely(skb->len < 10)) {
1452 		dev_kfree_skb(skb);
1453 		return true;
1454 	}
1455 
1456 	rcu_read_lock();
1457 
1458 	/* initialises tx */
1459 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1460 
1461 	if (unlikely(res_prepare == TX_DROP)) {
1462 		dev_kfree_skb(skb);
1463 		goto out;
1464 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1465 		goto out;
1466 	}
1467 
1468 	tx.channel = local->hw.conf.channel;
1469 	info->band = tx.channel->band;
1470 
1471 	if (!invoke_tx_handlers(&tx))
1472 		result = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
1473  out:
1474 	rcu_read_unlock();
1475 	return result;
1476 }
1477 
1478 /* device xmit handlers */
1479 
1480 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1481 				struct sk_buff *skb,
1482 				int head_need, bool may_encrypt)
1483 {
1484 	struct ieee80211_local *local = sdata->local;
1485 	int tail_need = 0;
1486 
1487 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1488 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1489 		tail_need -= skb_tailroom(skb);
1490 		tail_need = max_t(int, tail_need, 0);
1491 	}
1492 
1493 	if (head_need || tail_need) {
1494 		/* Sorry. Can't account for this any more */
1495 		skb_orphan(skb);
1496 	}
1497 
1498 	if (skb_cloned(skb))
1499 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1500 	else if (head_need || tail_need)
1501 		I802_DEBUG_INC(local->tx_expand_skb_head);
1502 	else
1503 		return 0;
1504 
1505 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1506 		wiphy_debug(local->hw.wiphy,
1507 			    "failed to reallocate TX buffer\n");
1508 		return -ENOMEM;
1509 	}
1510 
1511 	/* update truesize too */
1512 	skb->truesize += head_need + tail_need;
1513 
1514 	return 0;
1515 }
1516 
1517 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1518 			   struct sk_buff *skb)
1519 {
1520 	struct ieee80211_local *local = sdata->local;
1521 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1522 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1523 	struct ieee80211_sub_if_data *tmp_sdata;
1524 	int headroom;
1525 	bool may_encrypt;
1526 
1527 	rcu_read_lock();
1528 
1529 	if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1530 		int hdrlen;
1531 		u16 len_rthdr;
1532 
1533 		info->flags |= IEEE80211_TX_CTL_INJECTED |
1534 			       IEEE80211_TX_INTFL_HAS_RADIOTAP;
1535 
1536 		len_rthdr = ieee80211_get_radiotap_len(skb->data);
1537 		hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1538 		hdrlen = ieee80211_hdrlen(hdr->frame_control);
1539 
1540 		/* check the header is complete in the frame */
1541 		if (likely(skb->len >= len_rthdr + hdrlen)) {
1542 			/*
1543 			 * We process outgoing injected frames that have a
1544 			 * local address we handle as though they are our
1545 			 * own frames.
1546 			 * This code here isn't entirely correct, the local
1547 			 * MAC address is not necessarily enough to find
1548 			 * the interface to use; for that proper VLAN/WDS
1549 			 * support we will need a different mechanism.
1550 			 */
1551 
1552 			list_for_each_entry_rcu(tmp_sdata, &local->interfaces,
1553 						list) {
1554 				if (!ieee80211_sdata_running(tmp_sdata))
1555 					continue;
1556 				if (tmp_sdata->vif.type ==
1557 				    NL80211_IFTYPE_MONITOR ||
1558 				    tmp_sdata->vif.type ==
1559 				    NL80211_IFTYPE_AP_VLAN ||
1560 					tmp_sdata->vif.type ==
1561 				    NL80211_IFTYPE_WDS)
1562 					continue;
1563 				if (compare_ether_addr(tmp_sdata->vif.addr,
1564 						       hdr->addr2) == 0) {
1565 					sdata = tmp_sdata;
1566 					break;
1567 				}
1568 			}
1569 		}
1570 	}
1571 
1572 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1573 
1574 	headroom = local->tx_headroom;
1575 	if (may_encrypt)
1576 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1577 	headroom -= skb_headroom(skb);
1578 	headroom = max_t(int, 0, headroom);
1579 
1580 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1581 		dev_kfree_skb(skb);
1582 		rcu_read_unlock();
1583 		return;
1584 	}
1585 
1586 	hdr = (struct ieee80211_hdr *) skb->data;
1587 	info->control.vif = &sdata->vif;
1588 
1589 	if (ieee80211_vif_is_mesh(&sdata->vif) &&
1590 	    ieee80211_is_data(hdr->frame_control) &&
1591 		!is_multicast_ether_addr(hdr->addr1))
1592 			if (mesh_nexthop_lookup(skb, sdata)) {
1593 				/* skb queued: don't free */
1594 				rcu_read_unlock();
1595 				return;
1596 			}
1597 
1598 	ieee80211_set_qos_hdr(local, skb);
1599 	ieee80211_tx(sdata, skb, false);
1600 	rcu_read_unlock();
1601 }
1602 
1603 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1604 					 struct net_device *dev)
1605 {
1606 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1607 	struct ieee80211_channel *chan = local->hw.conf.channel;
1608 	struct ieee80211_radiotap_header *prthdr =
1609 		(struct ieee80211_radiotap_header *)skb->data;
1610 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1611 	u16 len_rthdr;
1612 
1613 	/*
1614 	 * Frame injection is not allowed if beaconing is not allowed
1615 	 * or if we need radar detection. Beaconing is usually not allowed when
1616 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1617 	 * Passive scan is also used in world regulatory domains where
1618 	 * your country is not known and as such it should be treated as
1619 	 * NO TX unless the channel is explicitly allowed in which case
1620 	 * your current regulatory domain would not have the passive scan
1621 	 * flag.
1622 	 *
1623 	 * Since AP mode uses monitor interfaces to inject/TX management
1624 	 * frames we can make AP mode the exception to this rule once it
1625 	 * supports radar detection as its implementation can deal with
1626 	 * radar detection by itself. We can do that later by adding a
1627 	 * monitor flag interfaces used for AP support.
1628 	 */
1629 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1630 	     IEEE80211_CHAN_PASSIVE_SCAN)))
1631 		goto fail;
1632 
1633 	/* check for not even having the fixed radiotap header part */
1634 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1635 		goto fail; /* too short to be possibly valid */
1636 
1637 	/* is it a header version we can trust to find length from? */
1638 	if (unlikely(prthdr->it_version))
1639 		goto fail; /* only version 0 is supported */
1640 
1641 	/* then there must be a radiotap header with a length we can use */
1642 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1643 
1644 	/* does the skb contain enough to deliver on the alleged length? */
1645 	if (unlikely(skb->len < len_rthdr))
1646 		goto fail; /* skb too short for claimed rt header extent */
1647 
1648 	/*
1649 	 * fix up the pointers accounting for the radiotap
1650 	 * header still being in there.  We are being given
1651 	 * a precooked IEEE80211 header so no need for
1652 	 * normal processing
1653 	 */
1654 	skb_set_mac_header(skb, len_rthdr);
1655 	/*
1656 	 * these are just fixed to the end of the rt area since we
1657 	 * don't have any better information and at this point, nobody cares
1658 	 */
1659 	skb_set_network_header(skb, len_rthdr);
1660 	skb_set_transport_header(skb, len_rthdr);
1661 
1662 	memset(info, 0, sizeof(*info));
1663 
1664 	info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1665 
1666 	/* pass the radiotap header up to xmit */
1667 	ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb);
1668 	return NETDEV_TX_OK;
1669 
1670 fail:
1671 	dev_kfree_skb(skb);
1672 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1673 }
1674 
1675 /**
1676  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1677  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1678  * @skb: packet to be sent
1679  * @dev: incoming interface
1680  *
1681  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1682  * not be freed, and caller is responsible for either retrying later or freeing
1683  * skb).
1684  *
1685  * This function takes in an Ethernet header and encapsulates it with suitable
1686  * IEEE 802.11 header based on which interface the packet is coming in. The
1687  * encapsulated packet will then be passed to master interface, wlan#.11, for
1688  * transmission (through low-level driver).
1689  */
1690 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1691 				    struct net_device *dev)
1692 {
1693 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1694 	struct ieee80211_local *local = sdata->local;
1695 	struct ieee80211_tx_info *info;
1696 	int ret = NETDEV_TX_BUSY, head_need;
1697 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1698 	__le16 fc;
1699 	struct ieee80211_hdr hdr;
1700 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1701 	struct mesh_path __maybe_unused *mppath = NULL;
1702 	const u8 *encaps_data;
1703 	int encaps_len, skip_header_bytes;
1704 	int nh_pos, h_pos;
1705 	struct sta_info *sta = NULL;
1706 	u32 sta_flags = 0;
1707 	struct sk_buff *tmp_skb;
1708 
1709 	if (unlikely(skb->len < ETH_HLEN)) {
1710 		ret = NETDEV_TX_OK;
1711 		goto fail;
1712 	}
1713 
1714 	/* convert Ethernet header to proper 802.11 header (based on
1715 	 * operation mode) */
1716 	ethertype = (skb->data[12] << 8) | skb->data[13];
1717 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1718 
1719 	switch (sdata->vif.type) {
1720 	case NL80211_IFTYPE_AP_VLAN:
1721 		rcu_read_lock();
1722 		sta = rcu_dereference(sdata->u.vlan.sta);
1723 		if (sta) {
1724 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1725 			/* RA TA DA SA */
1726 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1727 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1728 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1729 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1730 			hdrlen = 30;
1731 			sta_flags = get_sta_flags(sta);
1732 		}
1733 		rcu_read_unlock();
1734 		if (sta)
1735 			break;
1736 		/* fall through */
1737 	case NL80211_IFTYPE_AP:
1738 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1739 		/* DA BSSID SA */
1740 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1741 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1742 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1743 		hdrlen = 24;
1744 		break;
1745 	case NL80211_IFTYPE_WDS:
1746 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1747 		/* RA TA DA SA */
1748 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1749 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1750 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1751 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1752 		hdrlen = 30;
1753 		break;
1754 #ifdef CONFIG_MAC80211_MESH
1755 	case NL80211_IFTYPE_MESH_POINT:
1756 		if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1757 			/* Do not send frames with mesh_ttl == 0 */
1758 			sdata->u.mesh.mshstats.dropped_frames_ttl++;
1759 			ret = NETDEV_TX_OK;
1760 			goto fail;
1761 		}
1762 		rcu_read_lock();
1763 		if (!is_multicast_ether_addr(skb->data))
1764 			mppath = mpp_path_lookup(skb->data, sdata);
1765 
1766 		/*
1767 		 * Use address extension if it is a packet from
1768 		 * another interface or if we know the destination
1769 		 * is being proxied by a portal (i.e. portal address
1770 		 * differs from proxied address)
1771 		 */
1772 		if (compare_ether_addr(sdata->vif.addr,
1773 				       skb->data + ETH_ALEN) == 0 &&
1774 		    !(mppath && compare_ether_addr(mppath->mpp, skb->data))) {
1775 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1776 					skb->data, skb->data + ETH_ALEN);
1777 			rcu_read_unlock();
1778 			meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
1779 					sdata, NULL, NULL);
1780 		} else {
1781 			int is_mesh_mcast = 1;
1782 			const u8 *mesh_da;
1783 
1784 			if (is_multicast_ether_addr(skb->data))
1785 				/* DA TA mSA AE:SA */
1786 				mesh_da = skb->data;
1787 			else {
1788 				static const u8 bcast[ETH_ALEN] =
1789 					{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
1790 				if (mppath) {
1791 					/* RA TA mDA mSA AE:DA SA */
1792 					mesh_da = mppath->mpp;
1793 					is_mesh_mcast = 0;
1794 				} else {
1795 					/* DA TA mSA AE:SA */
1796 					mesh_da = bcast;
1797 				}
1798 			}
1799 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1800 					mesh_da, sdata->vif.addr);
1801 			rcu_read_unlock();
1802 			if (is_mesh_mcast)
1803 				meshhdrlen =
1804 					ieee80211_new_mesh_header(&mesh_hdr,
1805 							sdata,
1806 							skb->data + ETH_ALEN,
1807 							NULL);
1808 			else
1809 				meshhdrlen =
1810 					ieee80211_new_mesh_header(&mesh_hdr,
1811 							sdata,
1812 							skb->data,
1813 							skb->data + ETH_ALEN);
1814 
1815 		}
1816 		break;
1817 #endif
1818 	case NL80211_IFTYPE_STATION:
1819 		memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1820 		if (sdata->u.mgd.use_4addr &&
1821 		    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1822 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1823 			/* RA TA DA SA */
1824 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1825 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1826 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1827 			hdrlen = 30;
1828 		} else {
1829 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1830 			/* BSSID SA DA */
1831 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1832 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1833 			hdrlen = 24;
1834 		}
1835 		break;
1836 	case NL80211_IFTYPE_ADHOC:
1837 		/* DA SA BSSID */
1838 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1839 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1840 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1841 		hdrlen = 24;
1842 		break;
1843 	default:
1844 		ret = NETDEV_TX_OK;
1845 		goto fail;
1846 	}
1847 
1848 	/*
1849 	 * There's no need to try to look up the destination
1850 	 * if it is a multicast address (which can only happen
1851 	 * in AP mode)
1852 	 */
1853 	if (!is_multicast_ether_addr(hdr.addr1)) {
1854 		rcu_read_lock();
1855 		sta = sta_info_get(sdata, hdr.addr1);
1856 		if (sta)
1857 			sta_flags = get_sta_flags(sta);
1858 		rcu_read_unlock();
1859 	}
1860 
1861 	/* receiver and we are QoS enabled, use a QoS type frame */
1862 	if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1863 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1864 		hdrlen += 2;
1865 	}
1866 
1867 	/*
1868 	 * Drop unicast frames to unauthorised stations unless they are
1869 	 * EAPOL frames from the local station.
1870 	 */
1871 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1872 		unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1873 		      !(sta_flags & WLAN_STA_AUTHORIZED) &&
1874 		      !(cpu_to_be16(ethertype) == sdata->control_port_protocol &&
1875 		       compare_ether_addr(sdata->vif.addr,
1876 					  skb->data + ETH_ALEN) == 0))) {
1877 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1878 		if (net_ratelimit())
1879 			printk(KERN_DEBUG "%s: dropped frame to %pM"
1880 			       " (unauthorized port)\n", dev->name,
1881 			       hdr.addr1);
1882 #endif
1883 
1884 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1885 
1886 		ret = NETDEV_TX_OK;
1887 		goto fail;
1888 	}
1889 
1890 	/*
1891 	 * If the skb is shared we need to obtain our own copy.
1892 	 */
1893 	if (skb_shared(skb)) {
1894 		tmp_skb = skb;
1895 		skb = skb_clone(skb, GFP_ATOMIC);
1896 		kfree_skb(tmp_skb);
1897 
1898 		if (!skb) {
1899 			ret = NETDEV_TX_OK;
1900 			goto fail;
1901 		}
1902 	}
1903 
1904 	hdr.frame_control = fc;
1905 	hdr.duration_id = 0;
1906 	hdr.seq_ctrl = 0;
1907 
1908 	skip_header_bytes = ETH_HLEN;
1909 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1910 		encaps_data = bridge_tunnel_header;
1911 		encaps_len = sizeof(bridge_tunnel_header);
1912 		skip_header_bytes -= 2;
1913 	} else if (ethertype >= 0x600) {
1914 		encaps_data = rfc1042_header;
1915 		encaps_len = sizeof(rfc1042_header);
1916 		skip_header_bytes -= 2;
1917 	} else {
1918 		encaps_data = NULL;
1919 		encaps_len = 0;
1920 	}
1921 
1922 	nh_pos = skb_network_header(skb) - skb->data;
1923 	h_pos = skb_transport_header(skb) - skb->data;
1924 
1925 	skb_pull(skb, skip_header_bytes);
1926 	nh_pos -= skip_header_bytes;
1927 	h_pos -= skip_header_bytes;
1928 
1929 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1930 
1931 	/*
1932 	 * So we need to modify the skb header and hence need a copy of
1933 	 * that. The head_need variable above doesn't, so far, include
1934 	 * the needed header space that we don't need right away. If we
1935 	 * can, then we don't reallocate right now but only after the
1936 	 * frame arrives at the master device (if it does...)
1937 	 *
1938 	 * If we cannot, however, then we will reallocate to include all
1939 	 * the ever needed space. Also, if we need to reallocate it anyway,
1940 	 * make it big enough for everything we may ever need.
1941 	 */
1942 
1943 	if (head_need > 0 || skb_cloned(skb)) {
1944 		head_need += IEEE80211_ENCRYPT_HEADROOM;
1945 		head_need += local->tx_headroom;
1946 		head_need = max_t(int, 0, head_need);
1947 		if (ieee80211_skb_resize(sdata, skb, head_need, true))
1948 			goto fail;
1949 	}
1950 
1951 	if (encaps_data) {
1952 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1953 		nh_pos += encaps_len;
1954 		h_pos += encaps_len;
1955 	}
1956 
1957 #ifdef CONFIG_MAC80211_MESH
1958 	if (meshhdrlen > 0) {
1959 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1960 		nh_pos += meshhdrlen;
1961 		h_pos += meshhdrlen;
1962 	}
1963 #endif
1964 
1965 	if (ieee80211_is_data_qos(fc)) {
1966 		__le16 *qos_control;
1967 
1968 		qos_control = (__le16*) skb_push(skb, 2);
1969 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1970 		/*
1971 		 * Maybe we could actually set some fields here, for now just
1972 		 * initialise to zero to indicate no special operation.
1973 		 */
1974 		*qos_control = 0;
1975 	} else
1976 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1977 
1978 	nh_pos += hdrlen;
1979 	h_pos += hdrlen;
1980 
1981 	dev->stats.tx_packets++;
1982 	dev->stats.tx_bytes += skb->len;
1983 
1984 	/* Update skb pointers to various headers since this modified frame
1985 	 * is going to go through Linux networking code that may potentially
1986 	 * need things like pointer to IP header. */
1987 	skb_set_mac_header(skb, 0);
1988 	skb_set_network_header(skb, nh_pos);
1989 	skb_set_transport_header(skb, h_pos);
1990 
1991 	info = IEEE80211_SKB_CB(skb);
1992 	memset(info, 0, sizeof(*info));
1993 
1994 	dev->trans_start = jiffies;
1995 	ieee80211_xmit(sdata, skb);
1996 
1997 	return NETDEV_TX_OK;
1998 
1999  fail:
2000 	if (ret == NETDEV_TX_OK)
2001 		dev_kfree_skb(skb);
2002 
2003 	return ret;
2004 }
2005 
2006 
2007 /*
2008  * ieee80211_clear_tx_pending may not be called in a context where
2009  * it is possible that it packets could come in again.
2010  */
2011 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2012 {
2013 	int i;
2014 
2015 	for (i = 0; i < local->hw.queues; i++)
2016 		skb_queue_purge(&local->pending[i]);
2017 }
2018 
2019 /*
2020  * Returns false if the frame couldn't be transmitted but was queued instead,
2021  * which in this case means re-queued -- take as an indication to stop sending
2022  * more pending frames.
2023  */
2024 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2025 				     struct sk_buff *skb)
2026 {
2027 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2028 	struct ieee80211_sub_if_data *sdata;
2029 	struct sta_info *sta;
2030 	struct ieee80211_hdr *hdr;
2031 	bool result;
2032 
2033 	sdata = vif_to_sdata(info->control.vif);
2034 
2035 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2036 		result = ieee80211_tx(sdata, skb, true);
2037 	} else {
2038 		hdr = (struct ieee80211_hdr *)skb->data;
2039 		sta = sta_info_get(sdata, hdr->addr1);
2040 
2041 		result = __ieee80211_tx(local, &skb, sta, true);
2042 	}
2043 
2044 	return result;
2045 }
2046 
2047 /*
2048  * Transmit all pending packets. Called from tasklet.
2049  */
2050 void ieee80211_tx_pending(unsigned long data)
2051 {
2052 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2053 	struct ieee80211_sub_if_data *sdata;
2054 	unsigned long flags;
2055 	int i;
2056 	bool txok;
2057 
2058 	rcu_read_lock();
2059 
2060 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2061 	for (i = 0; i < local->hw.queues; i++) {
2062 		/*
2063 		 * If queue is stopped by something other than due to pending
2064 		 * frames, or we have no pending frames, proceed to next queue.
2065 		 */
2066 		if (local->queue_stop_reasons[i] ||
2067 		    skb_queue_empty(&local->pending[i]))
2068 			continue;
2069 
2070 		while (!skb_queue_empty(&local->pending[i])) {
2071 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2072 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2073 
2074 			if (WARN_ON(!info->control.vif)) {
2075 				kfree_skb(skb);
2076 				continue;
2077 			}
2078 
2079 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2080 						flags);
2081 
2082 			txok = ieee80211_tx_pending_skb(local, skb);
2083 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2084 					  flags);
2085 			if (!txok)
2086 				break;
2087 		}
2088 
2089 		if (skb_queue_empty(&local->pending[i]))
2090 			list_for_each_entry_rcu(sdata, &local->interfaces, list)
2091 				netif_wake_subqueue(sdata->dev, i);
2092 	}
2093 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2094 
2095 	rcu_read_unlock();
2096 }
2097 
2098 /* functions for drivers to get certain frames */
2099 
2100 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
2101 				     struct sk_buff *skb,
2102 				     struct beacon_data *beacon)
2103 {
2104 	u8 *pos, *tim;
2105 	int aid0 = 0;
2106 	int i, have_bits = 0, n1, n2;
2107 
2108 	/* Generate bitmap for TIM only if there are any STAs in power save
2109 	 * mode. */
2110 	if (atomic_read(&bss->num_sta_ps) > 0)
2111 		/* in the hope that this is faster than
2112 		 * checking byte-for-byte */
2113 		have_bits = !bitmap_empty((unsigned long*)bss->tim,
2114 					  IEEE80211_MAX_AID+1);
2115 
2116 	if (bss->dtim_count == 0)
2117 		bss->dtim_count = beacon->dtim_period - 1;
2118 	else
2119 		bss->dtim_count--;
2120 
2121 	tim = pos = (u8 *) skb_put(skb, 6);
2122 	*pos++ = WLAN_EID_TIM;
2123 	*pos++ = 4;
2124 	*pos++ = bss->dtim_count;
2125 	*pos++ = beacon->dtim_period;
2126 
2127 	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
2128 		aid0 = 1;
2129 
2130 	bss->dtim_bc_mc = aid0 == 1;
2131 
2132 	if (have_bits) {
2133 		/* Find largest even number N1 so that bits numbered 1 through
2134 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2135 		 * (N2 + 1) x 8 through 2007 are 0. */
2136 		n1 = 0;
2137 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2138 			if (bss->tim[i]) {
2139 				n1 = i & 0xfe;
2140 				break;
2141 			}
2142 		}
2143 		n2 = n1;
2144 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2145 			if (bss->tim[i]) {
2146 				n2 = i;
2147 				break;
2148 			}
2149 		}
2150 
2151 		/* Bitmap control */
2152 		*pos++ = n1 | aid0;
2153 		/* Part Virt Bitmap */
2154 		memcpy(pos, bss->tim + n1, n2 - n1 + 1);
2155 
2156 		tim[1] = n2 - n1 + 4;
2157 		skb_put(skb, n2 - n1);
2158 	} else {
2159 		*pos++ = aid0; /* Bitmap control */
2160 		*pos++ = 0; /* Part Virt Bitmap */
2161 	}
2162 }
2163 
2164 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2165 					 struct ieee80211_vif *vif,
2166 					 u16 *tim_offset, u16 *tim_length)
2167 {
2168 	struct ieee80211_local *local = hw_to_local(hw);
2169 	struct sk_buff *skb = NULL;
2170 	struct ieee80211_tx_info *info;
2171 	struct ieee80211_sub_if_data *sdata = NULL;
2172 	struct ieee80211_if_ap *ap = NULL;
2173 	struct beacon_data *beacon;
2174 	struct ieee80211_supported_band *sband;
2175 	enum ieee80211_band band = local->hw.conf.channel->band;
2176 	struct ieee80211_tx_rate_control txrc;
2177 
2178 	sband = local->hw.wiphy->bands[band];
2179 
2180 	rcu_read_lock();
2181 
2182 	sdata = vif_to_sdata(vif);
2183 
2184 	if (!ieee80211_sdata_running(sdata))
2185 		goto out;
2186 
2187 	if (tim_offset)
2188 		*tim_offset = 0;
2189 	if (tim_length)
2190 		*tim_length = 0;
2191 
2192 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2193 		ap = &sdata->u.ap;
2194 		beacon = rcu_dereference(ap->beacon);
2195 		if (beacon) {
2196 			/*
2197 			 * headroom, head length,
2198 			 * tail length and maximum TIM length
2199 			 */
2200 			skb = dev_alloc_skb(local->tx_headroom +
2201 					    beacon->head_len +
2202 					    beacon->tail_len + 256);
2203 			if (!skb)
2204 				goto out;
2205 
2206 			skb_reserve(skb, local->tx_headroom);
2207 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2208 			       beacon->head_len);
2209 
2210 			/*
2211 			 * Not very nice, but we want to allow the driver to call
2212 			 * ieee80211_beacon_get() as a response to the set_tim()
2213 			 * callback. That, however, is already invoked under the
2214 			 * sta_lock to guarantee consistent and race-free update
2215 			 * of the tim bitmap in mac80211 and the driver.
2216 			 */
2217 			if (local->tim_in_locked_section) {
2218 				ieee80211_beacon_add_tim(ap, skb, beacon);
2219 			} else {
2220 				unsigned long flags;
2221 
2222 				spin_lock_irqsave(&local->sta_lock, flags);
2223 				ieee80211_beacon_add_tim(ap, skb, beacon);
2224 				spin_unlock_irqrestore(&local->sta_lock, flags);
2225 			}
2226 
2227 			if (tim_offset)
2228 				*tim_offset = beacon->head_len;
2229 			if (tim_length)
2230 				*tim_length = skb->len - beacon->head_len;
2231 
2232 			if (beacon->tail)
2233 				memcpy(skb_put(skb, beacon->tail_len),
2234 				       beacon->tail, beacon->tail_len);
2235 		} else
2236 			goto out;
2237 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2238 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2239 		struct ieee80211_hdr *hdr;
2240 		struct sk_buff *presp = rcu_dereference(ifibss->presp);
2241 
2242 		if (!presp)
2243 			goto out;
2244 
2245 		skb = skb_copy(presp, GFP_ATOMIC);
2246 		if (!skb)
2247 			goto out;
2248 
2249 		hdr = (struct ieee80211_hdr *) skb->data;
2250 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2251 						 IEEE80211_STYPE_BEACON);
2252 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2253 		struct ieee80211_mgmt *mgmt;
2254 		u8 *pos;
2255 
2256 #ifdef CONFIG_MAC80211_MESH
2257 		if (!sdata->u.mesh.mesh_id_len)
2258 			goto out;
2259 #endif
2260 
2261 		/* headroom, head length, tail length and maximum TIM length */
2262 		skb = dev_alloc_skb(local->tx_headroom + 400 +
2263 				sdata->u.mesh.ie_len);
2264 		if (!skb)
2265 			goto out;
2266 
2267 		skb_reserve(skb, local->hw.extra_tx_headroom);
2268 		mgmt = (struct ieee80211_mgmt *)
2269 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2270 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2271 		mgmt->frame_control =
2272 		    cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2273 		memset(mgmt->da, 0xff, ETH_ALEN);
2274 		memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
2275 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
2276 		mgmt->u.beacon.beacon_int =
2277 			cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2278 		mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2279 
2280 		pos = skb_put(skb, 2);
2281 		*pos++ = WLAN_EID_SSID;
2282 		*pos++ = 0x0;
2283 
2284 		mesh_mgmt_ies_add(skb, sdata);
2285 	} else {
2286 		WARN_ON(1);
2287 		goto out;
2288 	}
2289 
2290 	info = IEEE80211_SKB_CB(skb);
2291 
2292 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2293 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2294 	info->band = band;
2295 
2296 	memset(&txrc, 0, sizeof(txrc));
2297 	txrc.hw = hw;
2298 	txrc.sband = sband;
2299 	txrc.bss_conf = &sdata->vif.bss_conf;
2300 	txrc.skb = skb;
2301 	txrc.reported_rate.idx = -1;
2302 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2303 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
2304 		txrc.max_rate_idx = -1;
2305 	else
2306 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2307 	txrc.bss = true;
2308 	rate_control_get_rate(sdata, NULL, &txrc);
2309 
2310 	info->control.vif = vif;
2311 
2312 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2313 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2314 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2315  out:
2316 	rcu_read_unlock();
2317 	return skb;
2318 }
2319 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2320 
2321 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2322 				     struct ieee80211_vif *vif)
2323 {
2324 	struct ieee80211_sub_if_data *sdata;
2325 	struct ieee80211_if_managed *ifmgd;
2326 	struct ieee80211_pspoll *pspoll;
2327 	struct ieee80211_local *local;
2328 	struct sk_buff *skb;
2329 
2330 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2331 		return NULL;
2332 
2333 	sdata = vif_to_sdata(vif);
2334 	ifmgd = &sdata->u.mgd;
2335 	local = sdata->local;
2336 
2337 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2338 	if (!skb) {
2339 		printk(KERN_DEBUG "%s: failed to allocate buffer for "
2340 		       "pspoll template\n", sdata->name);
2341 		return NULL;
2342 	}
2343 	skb_reserve(skb, local->hw.extra_tx_headroom);
2344 
2345 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2346 	memset(pspoll, 0, sizeof(*pspoll));
2347 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2348 					    IEEE80211_STYPE_PSPOLL);
2349 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2350 
2351 	/* aid in PS-Poll has its two MSBs each set to 1 */
2352 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2353 
2354 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2355 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2356 
2357 	return skb;
2358 }
2359 EXPORT_SYMBOL(ieee80211_pspoll_get);
2360 
2361 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2362 				       struct ieee80211_vif *vif)
2363 {
2364 	struct ieee80211_hdr_3addr *nullfunc;
2365 	struct ieee80211_sub_if_data *sdata;
2366 	struct ieee80211_if_managed *ifmgd;
2367 	struct ieee80211_local *local;
2368 	struct sk_buff *skb;
2369 
2370 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2371 		return NULL;
2372 
2373 	sdata = vif_to_sdata(vif);
2374 	ifmgd = &sdata->u.mgd;
2375 	local = sdata->local;
2376 
2377 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2378 	if (!skb) {
2379 		printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
2380 		       "template\n", sdata->name);
2381 		return NULL;
2382 	}
2383 	skb_reserve(skb, local->hw.extra_tx_headroom);
2384 
2385 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2386 							  sizeof(*nullfunc));
2387 	memset(nullfunc, 0, sizeof(*nullfunc));
2388 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2389 					      IEEE80211_STYPE_NULLFUNC |
2390 					      IEEE80211_FCTL_TODS);
2391 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2392 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2393 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2394 
2395 	return skb;
2396 }
2397 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2398 
2399 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2400 				       struct ieee80211_vif *vif,
2401 				       const u8 *ssid, size_t ssid_len,
2402 				       const u8 *ie, size_t ie_len)
2403 {
2404 	struct ieee80211_sub_if_data *sdata;
2405 	struct ieee80211_local *local;
2406 	struct ieee80211_hdr_3addr *hdr;
2407 	struct sk_buff *skb;
2408 	size_t ie_ssid_len;
2409 	u8 *pos;
2410 
2411 	sdata = vif_to_sdata(vif);
2412 	local = sdata->local;
2413 	ie_ssid_len = 2 + ssid_len;
2414 
2415 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2416 			    ie_ssid_len + ie_len);
2417 	if (!skb) {
2418 		printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
2419 		       "request template\n", sdata->name);
2420 		return NULL;
2421 	}
2422 
2423 	skb_reserve(skb, local->hw.extra_tx_headroom);
2424 
2425 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2426 	memset(hdr, 0, sizeof(*hdr));
2427 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2428 					 IEEE80211_STYPE_PROBE_REQ);
2429 	memset(hdr->addr1, 0xff, ETH_ALEN);
2430 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2431 	memset(hdr->addr3, 0xff, ETH_ALEN);
2432 
2433 	pos = skb_put(skb, ie_ssid_len);
2434 	*pos++ = WLAN_EID_SSID;
2435 	*pos++ = ssid_len;
2436 	if (ssid)
2437 		memcpy(pos, ssid, ssid_len);
2438 	pos += ssid_len;
2439 
2440 	if (ie) {
2441 		pos = skb_put(skb, ie_len);
2442 		memcpy(pos, ie, ie_len);
2443 	}
2444 
2445 	return skb;
2446 }
2447 EXPORT_SYMBOL(ieee80211_probereq_get);
2448 
2449 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2450 		       const void *frame, size_t frame_len,
2451 		       const struct ieee80211_tx_info *frame_txctl,
2452 		       struct ieee80211_rts *rts)
2453 {
2454 	const struct ieee80211_hdr *hdr = frame;
2455 
2456 	rts->frame_control =
2457 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2458 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2459 					       frame_txctl);
2460 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2461 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2462 }
2463 EXPORT_SYMBOL(ieee80211_rts_get);
2464 
2465 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2466 			     const void *frame, size_t frame_len,
2467 			     const struct ieee80211_tx_info *frame_txctl,
2468 			     struct ieee80211_cts *cts)
2469 {
2470 	const struct ieee80211_hdr *hdr = frame;
2471 
2472 	cts->frame_control =
2473 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2474 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2475 						     frame_len, frame_txctl);
2476 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2477 }
2478 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2479 
2480 struct sk_buff *
2481 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2482 			  struct ieee80211_vif *vif)
2483 {
2484 	struct ieee80211_local *local = hw_to_local(hw);
2485 	struct sk_buff *skb = NULL;
2486 	struct ieee80211_tx_data tx;
2487 	struct ieee80211_sub_if_data *sdata;
2488 	struct ieee80211_if_ap *bss = NULL;
2489 	struct beacon_data *beacon;
2490 	struct ieee80211_tx_info *info;
2491 
2492 	sdata = vif_to_sdata(vif);
2493 	bss = &sdata->u.ap;
2494 
2495 	rcu_read_lock();
2496 	beacon = rcu_dereference(bss->beacon);
2497 
2498 	if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2499 		goto out;
2500 
2501 	if (bss->dtim_count != 0 || !bss->dtim_bc_mc)
2502 		goto out; /* send buffered bc/mc only after DTIM beacon */
2503 
2504 	while (1) {
2505 		skb = skb_dequeue(&bss->ps_bc_buf);
2506 		if (!skb)
2507 			goto out;
2508 		local->total_ps_buffered--;
2509 
2510 		if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2511 			struct ieee80211_hdr *hdr =
2512 				(struct ieee80211_hdr *) skb->data;
2513 			/* more buffered multicast/broadcast frames ==> set
2514 			 * MoreData flag in IEEE 802.11 header to inform PS
2515 			 * STAs */
2516 			hdr->frame_control |=
2517 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2518 		}
2519 
2520 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2521 			break;
2522 		dev_kfree_skb_any(skb);
2523 	}
2524 
2525 	info = IEEE80211_SKB_CB(skb);
2526 
2527 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2528 	tx.channel = local->hw.conf.channel;
2529 	info->band = tx.channel->band;
2530 
2531 	if (invoke_tx_handlers(&tx))
2532 		skb = NULL;
2533  out:
2534 	rcu_read_unlock();
2535 
2536 	return skb;
2537 }
2538 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2539 
2540 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
2541 {
2542 	skb_set_mac_header(skb, 0);
2543 	skb_set_network_header(skb, 0);
2544 	skb_set_transport_header(skb, 0);
2545 
2546 	/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
2547 	skb_set_queue_mapping(skb, IEEE80211_AC_VO);
2548 	skb->priority = 7;
2549 
2550 	/*
2551 	 * The other path calling ieee80211_xmit is from the tasklet,
2552 	 * and while we can handle concurrent transmissions locking
2553 	 * requirements are that we do not come into tx with bhs on.
2554 	 */
2555 	local_bh_disable();
2556 	ieee80211_xmit(sdata, skb);
2557 	local_bh_enable();
2558 }
2559