xref: /openbmc/linux/net/mac80211/tx.c (revision ca79522c)
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 <linux/export.h>
22 #include <net/net_namespace.h>
23 #include <net/ieee80211_radiotap.h>
24 #include <net/cfg80211.h>
25 #include <net/mac80211.h>
26 #include <asm/unaligned.h>
27 
28 #include "ieee80211_i.h"
29 #include "driver-ops.h"
30 #include "led.h"
31 #include "mesh.h"
32 #include "wep.h"
33 #include "wpa.h"
34 #include "wme.h"
35 #include "rate.h"
36 
37 /* misc utils */
38 
39 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
40 				 struct sk_buff *skb, int group_addr,
41 				 int next_frag_len)
42 {
43 	int rate, mrate, erp, dur, i;
44 	struct ieee80211_rate *txrate;
45 	struct ieee80211_local *local = tx->local;
46 	struct ieee80211_supported_band *sband;
47 	struct ieee80211_hdr *hdr;
48 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
49 
50 	/* assume HW handles this */
51 	if (tx->rate.flags & IEEE80211_TX_RC_MCS)
52 		return 0;
53 
54 	/* uh huh? */
55 	if (WARN_ON_ONCE(tx->rate.idx < 0))
56 		return 0;
57 
58 	sband = local->hw.wiphy->bands[info->band];
59 	txrate = &sband->bitrates[tx->rate.idx];
60 
61 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
62 
63 	/*
64 	 * data and mgmt (except PS Poll):
65 	 * - during CFP: 32768
66 	 * - during contention period:
67 	 *   if addr1 is group address: 0
68 	 *   if more fragments = 0 and addr1 is individual address: time to
69 	 *      transmit one ACK plus SIFS
70 	 *   if more fragments = 1 and addr1 is individual address: time to
71 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
72 	 *
73 	 * IEEE 802.11, 9.6:
74 	 * - control response frame (CTS or ACK) shall be transmitted using the
75 	 *   same rate as the immediately previous frame in the frame exchange
76 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
77 	 *   at the highest possible rate belonging to the PHY rates in the
78 	 *   BSSBasicRateSet
79 	 */
80 	hdr = (struct ieee80211_hdr *)skb->data;
81 	if (ieee80211_is_ctl(hdr->frame_control)) {
82 		/* TODO: These control frames are not currently sent by
83 		 * mac80211, but should they be implemented, this function
84 		 * needs to be updated to support duration field calculation.
85 		 *
86 		 * RTS: time needed to transmit pending data/mgmt frame plus
87 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
88 		 * CTS: duration of immediately previous RTS minus time
89 		 *    required to transmit CTS and its SIFS
90 		 * ACK: 0 if immediately previous directed data/mgmt had
91 		 *    more=0, with more=1 duration in ACK frame is duration
92 		 *    from previous frame minus time needed to transmit ACK
93 		 *    and its SIFS
94 		 * PS Poll: BIT(15) | BIT(14) | aid
95 		 */
96 		return 0;
97 	}
98 
99 	/* data/mgmt */
100 	if (0 /* FIX: data/mgmt during CFP */)
101 		return cpu_to_le16(32768);
102 
103 	if (group_addr) /* Group address as the destination - no ACK */
104 		return 0;
105 
106 	/* Individual destination address:
107 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
108 	 * CTS and ACK frames shall be transmitted using the highest rate in
109 	 * basic rate set that is less than or equal to the rate of the
110 	 * immediately previous frame and that is using the same modulation
111 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
112 	 * the highest mandatory rate of the PHY that is less than or equal to
113 	 * the rate of the previous frame is used.
114 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
115 	 */
116 	rate = -1;
117 	/* use lowest available if everything fails */
118 	mrate = sband->bitrates[0].bitrate;
119 	for (i = 0; i < sband->n_bitrates; i++) {
120 		struct ieee80211_rate *r = &sband->bitrates[i];
121 
122 		if (r->bitrate > txrate->bitrate)
123 			break;
124 
125 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
126 			rate = r->bitrate;
127 
128 		switch (sband->band) {
129 		case IEEE80211_BAND_2GHZ: {
130 			u32 flag;
131 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
132 				flag = IEEE80211_RATE_MANDATORY_G;
133 			else
134 				flag = IEEE80211_RATE_MANDATORY_B;
135 			if (r->flags & flag)
136 				mrate = r->bitrate;
137 			break;
138 		}
139 		case IEEE80211_BAND_5GHZ:
140 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
141 				mrate = r->bitrate;
142 			break;
143 		case IEEE80211_BAND_60GHZ:
144 			/* TODO, for now fall through */
145 		case IEEE80211_NUM_BANDS:
146 			WARN_ON(1);
147 			break;
148 		}
149 	}
150 	if (rate == -1) {
151 		/* No matching basic rate found; use highest suitable mandatory
152 		 * PHY rate */
153 		rate = mrate;
154 	}
155 
156 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
157 	if (ieee80211_is_data_qos(hdr->frame_control) &&
158 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
159 		dur = 0;
160 	else
161 		/* Time needed to transmit ACK
162 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
163 		 * to closest integer */
164 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
165 				tx->sdata->vif.bss_conf.use_short_preamble);
166 
167 	if (next_frag_len) {
168 		/* Frame is fragmented: duration increases with time needed to
169 		 * transmit next fragment plus ACK and 2 x SIFS. */
170 		dur *= 2; /* ACK + SIFS */
171 		/* next fragment */
172 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
173 				txrate->bitrate, erp,
174 				tx->sdata->vif.bss_conf.use_short_preamble);
175 	}
176 
177 	return cpu_to_le16(dur);
178 }
179 
180 /* tx handlers */
181 static ieee80211_tx_result debug_noinline
182 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
183 {
184 	struct ieee80211_local *local = tx->local;
185 	struct ieee80211_if_managed *ifmgd;
186 
187 	/* driver doesn't support power save */
188 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
189 		return TX_CONTINUE;
190 
191 	/* hardware does dynamic power save */
192 	if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
193 		return TX_CONTINUE;
194 
195 	/* dynamic power save disabled */
196 	if (local->hw.conf.dynamic_ps_timeout <= 0)
197 		return TX_CONTINUE;
198 
199 	/* we are scanning, don't enable power save */
200 	if (local->scanning)
201 		return TX_CONTINUE;
202 
203 	if (!local->ps_sdata)
204 		return TX_CONTINUE;
205 
206 	/* No point if we're going to suspend */
207 	if (local->quiescing)
208 		return TX_CONTINUE;
209 
210 	/* dynamic ps is supported only in managed mode */
211 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
212 		return TX_CONTINUE;
213 
214 	ifmgd = &tx->sdata->u.mgd;
215 
216 	/*
217 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
218 	 * u-apsd enabled and the frame is in voip class. This effectively
219 	 * means that even if all access categories have u-apsd enabled, in
220 	 * practise u-apsd is only used with the voip ac. This is a
221 	 * workaround for the case when received voip class packets do not
222 	 * have correct qos tag for some reason, due the network or the
223 	 * peer application.
224 	 *
225 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
226 	 * changed via debugfs, user needs to reassociate manually to have
227 	 * everything in sync.
228 	 */
229 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
230 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
231 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
232 		return TX_CONTINUE;
233 
234 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
235 		ieee80211_stop_queues_by_reason(&local->hw,
236 						IEEE80211_MAX_QUEUE_MAP,
237 						IEEE80211_QUEUE_STOP_REASON_PS);
238 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
239 		ieee80211_queue_work(&local->hw,
240 				     &local->dynamic_ps_disable_work);
241 	}
242 
243 	/* Don't restart the timer if we're not disassociated */
244 	if (!ifmgd->associated)
245 		return TX_CONTINUE;
246 
247 	mod_timer(&local->dynamic_ps_timer, jiffies +
248 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
249 
250 	return TX_CONTINUE;
251 }
252 
253 static ieee80211_tx_result debug_noinline
254 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
255 {
256 
257 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
258 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
259 	bool assoc = false;
260 
261 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
262 		return TX_CONTINUE;
263 
264 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
265 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
266 	    !ieee80211_is_probe_req(hdr->frame_control) &&
267 	    !ieee80211_is_nullfunc(hdr->frame_control))
268 		/*
269 		 * When software scanning only nullfunc frames (to notify
270 		 * the sleep state to the AP) and probe requests (for the
271 		 * active scan) are allowed, all other frames should not be
272 		 * sent and we should not get here, but if we do
273 		 * nonetheless, drop them to avoid sending them
274 		 * off-channel. See the link below and
275 		 * ieee80211_start_scan() for more.
276 		 *
277 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
278 		 */
279 		return TX_DROP;
280 
281 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
282 		return TX_CONTINUE;
283 
284 	if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
285 		return TX_CONTINUE;
286 
287 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
288 		return TX_CONTINUE;
289 
290 	if (tx->sta)
291 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
292 
293 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
294 		if (unlikely(!assoc &&
295 			     ieee80211_is_data(hdr->frame_control))) {
296 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
297 			sdata_info(tx->sdata,
298 				   "dropped data frame to not associated station %pM\n",
299 				   hdr->addr1);
300 #endif
301 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
302 			return TX_DROP;
303 		}
304 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
305 			    ieee80211_is_data(hdr->frame_control) &&
306 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
307 		/*
308 		 * No associated STAs - no need to send multicast
309 		 * frames.
310 		 */
311 		return TX_DROP;
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 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
329 		struct ps_data *ps;
330 
331 		if (sdata->vif.type == NL80211_IFTYPE_AP)
332 			ps = &sdata->u.ap.ps;
333 		else if (ieee80211_vif_is_mesh(&sdata->vif))
334 			ps = &sdata->u.mesh.ps;
335 		else
336 			continue;
337 
338 		skb = skb_dequeue(&ps->bc_buf);
339 		if (skb) {
340 			purged++;
341 			dev_kfree_skb(skb);
342 		}
343 		total += skb_queue_len(&ps->bc_buf);
344 	}
345 
346 	/*
347 	 * Drop one frame from each station from the lowest-priority
348 	 * AC that has frames at all.
349 	 */
350 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
351 		int ac;
352 
353 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
354 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
355 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
356 			if (skb) {
357 				purged++;
358 				ieee80211_free_txskb(&local->hw, skb);
359 				break;
360 			}
361 		}
362 	}
363 
364 	local->total_ps_buffered = total;
365 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
366 }
367 
368 static ieee80211_tx_result
369 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
370 {
371 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
372 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
373 	struct ps_data *ps;
374 
375 	/*
376 	 * broadcast/multicast frame
377 	 *
378 	 * If any of the associated/peer stations is in power save mode,
379 	 * the frame is buffered to be sent after DTIM beacon frame.
380 	 * This is done either by the hardware or us.
381 	 */
382 
383 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
384 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
385 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
386 		if (!tx->sdata->bss)
387 			return TX_CONTINUE;
388 
389 		ps = &tx->sdata->bss->ps;
390 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
391 		ps = &tx->sdata->u.mesh.ps;
392 	} else {
393 		return TX_CONTINUE;
394 	}
395 
396 
397 	/* no buffering for ordered frames */
398 	if (ieee80211_has_order(hdr->frame_control))
399 		return TX_CONTINUE;
400 
401 	/* no stations in PS mode */
402 	if (!atomic_read(&ps->num_sta_ps))
403 		return TX_CONTINUE;
404 
405 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
406 	if (tx->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
407 		info->hw_queue = tx->sdata->vif.cab_queue;
408 
409 	/* device releases frame after DTIM beacon */
410 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
411 		return TX_CONTINUE;
412 
413 	/* buffered in mac80211 */
414 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
415 		purge_old_ps_buffers(tx->local);
416 
417 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
418 		ps_dbg(tx->sdata,
419 		       "BC TX buffer full - dropping the oldest frame\n");
420 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
421 	} else
422 		tx->local->total_ps_buffered++;
423 
424 	skb_queue_tail(&ps->bc_buf, tx->skb);
425 
426 	return TX_QUEUED;
427 }
428 
429 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
430 			     struct sk_buff *skb)
431 {
432 	if (!ieee80211_is_mgmt(fc))
433 		return 0;
434 
435 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
436 		return 0;
437 
438 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
439 					    skb->data))
440 		return 0;
441 
442 	return 1;
443 }
444 
445 static ieee80211_tx_result
446 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
447 {
448 	struct sta_info *sta = tx->sta;
449 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
450 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
451 	struct ieee80211_local *local = tx->local;
452 
453 	if (unlikely(!sta))
454 		return TX_CONTINUE;
455 
456 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
457 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
458 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
459 		int ac = skb_get_queue_mapping(tx->skb);
460 
461 		/* only deauth, disassoc and action are bufferable MMPDUs */
462 		if (ieee80211_is_mgmt(hdr->frame_control) &&
463 		    !ieee80211_is_deauth(hdr->frame_control) &&
464 		    !ieee80211_is_disassoc(hdr->frame_control) &&
465 		    !ieee80211_is_action(hdr->frame_control)) {
466 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
467 			return TX_CONTINUE;
468 		}
469 
470 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
471 		       sta->sta.addr, sta->sta.aid, ac);
472 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
473 			purge_old_ps_buffers(tx->local);
474 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
475 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
476 			ps_dbg(tx->sdata,
477 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
478 			       sta->sta.addr, ac);
479 			ieee80211_free_txskb(&local->hw, old);
480 		} else
481 			tx->local->total_ps_buffered++;
482 
483 		info->control.jiffies = jiffies;
484 		info->control.vif = &tx->sdata->vif;
485 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
486 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
487 
488 		if (!timer_pending(&local->sta_cleanup))
489 			mod_timer(&local->sta_cleanup,
490 				  round_jiffies(jiffies +
491 						STA_INFO_CLEANUP_INTERVAL));
492 
493 		/*
494 		 * We queued up some frames, so the TIM bit might
495 		 * need to be set, recalculate it.
496 		 */
497 		sta_info_recalc_tim(sta);
498 
499 		return TX_QUEUED;
500 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
501 		ps_dbg(tx->sdata,
502 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
503 		       sta->sta.addr);
504 	}
505 
506 	return TX_CONTINUE;
507 }
508 
509 static ieee80211_tx_result debug_noinline
510 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
511 {
512 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
513 		return TX_CONTINUE;
514 
515 	if (tx->flags & IEEE80211_TX_UNICAST)
516 		return ieee80211_tx_h_unicast_ps_buf(tx);
517 	else
518 		return ieee80211_tx_h_multicast_ps_buf(tx);
519 }
520 
521 static ieee80211_tx_result debug_noinline
522 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
523 {
524 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
525 
526 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
527 		     tx->sdata->control_port_no_encrypt))
528 		info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
529 
530 	return TX_CONTINUE;
531 }
532 
533 static ieee80211_tx_result debug_noinline
534 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
535 {
536 	struct ieee80211_key *key;
537 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
538 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
539 
540 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
541 		tx->key = NULL;
542 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
543 		tx->key = key;
544 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
545 		 is_multicast_ether_addr(hdr->addr1) &&
546 		 ieee80211_is_robust_mgmt_frame(hdr) &&
547 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
548 		tx->key = key;
549 	else if (is_multicast_ether_addr(hdr->addr1) &&
550 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
551 		tx->key = key;
552 	else if (!is_multicast_ether_addr(hdr->addr1) &&
553 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
554 		tx->key = key;
555 	else if (info->flags & IEEE80211_TX_CTL_INJECTED)
556 		tx->key = NULL;
557 	else if (!tx->sdata->drop_unencrypted)
558 		tx->key = NULL;
559 	else if (tx->skb->protocol == tx->sdata->control_port_protocol)
560 		tx->key = NULL;
561 	else if (ieee80211_is_robust_mgmt_frame(hdr) &&
562 		 !(ieee80211_is_action(hdr->frame_control) &&
563 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))
564 		tx->key = NULL;
565 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
566 		 !ieee80211_is_robust_mgmt_frame(hdr))
567 		tx->key = NULL;
568 	else {
569 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
570 		return TX_DROP;
571 	}
572 
573 	if (tx->key) {
574 		bool skip_hw = false;
575 
576 		tx->key->tx_rx_count++;
577 		/* TODO: add threshold stuff again */
578 
579 		switch (tx->key->conf.cipher) {
580 		case WLAN_CIPHER_SUITE_WEP40:
581 		case WLAN_CIPHER_SUITE_WEP104:
582 		case WLAN_CIPHER_SUITE_TKIP:
583 			if (!ieee80211_is_data_present(hdr->frame_control))
584 				tx->key = NULL;
585 			break;
586 		case WLAN_CIPHER_SUITE_CCMP:
587 			if (!ieee80211_is_data_present(hdr->frame_control) &&
588 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
589 					       tx->skb))
590 				tx->key = NULL;
591 			else
592 				skip_hw = (tx->key->conf.flags &
593 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
594 					ieee80211_is_mgmt(hdr->frame_control);
595 			break;
596 		case WLAN_CIPHER_SUITE_AES_CMAC:
597 			if (!ieee80211_is_mgmt(hdr->frame_control))
598 				tx->key = NULL;
599 			break;
600 		}
601 
602 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
603 			     !ieee80211_is_deauth(hdr->frame_control)))
604 			return TX_DROP;
605 
606 		if (!skip_hw && tx->key &&
607 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
608 			info->control.hw_key = &tx->key->conf;
609 	}
610 
611 	return TX_CONTINUE;
612 }
613 
614 static ieee80211_tx_result debug_noinline
615 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
616 {
617 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
618 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
619 	struct ieee80211_supported_band *sband;
620 	u32 len;
621 	struct ieee80211_tx_rate_control txrc;
622 	struct ieee80211_sta_rates *ratetbl = NULL;
623 	bool assoc = false;
624 
625 	memset(&txrc, 0, sizeof(txrc));
626 
627 	sband = tx->local->hw.wiphy->bands[info->band];
628 
629 	len = min_t(u32, tx->skb->len + FCS_LEN,
630 			 tx->local->hw.wiphy->frag_threshold);
631 
632 	/* set up the tx rate control struct we give the RC algo */
633 	txrc.hw = &tx->local->hw;
634 	txrc.sband = sband;
635 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
636 	txrc.skb = tx->skb;
637 	txrc.reported_rate.idx = -1;
638 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
639 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
640 		txrc.max_rate_idx = -1;
641 	else
642 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
643 
644 	if (tx->sdata->rc_has_mcs_mask[info->band])
645 		txrc.rate_idx_mcs_mask =
646 			tx->sdata->rc_rateidx_mcs_mask[info->band];
647 
648 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
649 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
650 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
651 
652 	/* set up RTS protection if desired */
653 	if (len > tx->local->hw.wiphy->rts_threshold) {
654 		txrc.rts = true;
655 	}
656 
657 	info->control.use_rts = txrc.rts;
658 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
659 
660 	/*
661 	 * Use short preamble if the BSS can handle it, but not for
662 	 * management frames unless we know the receiver can handle
663 	 * that -- the management frame might be to a station that
664 	 * just wants a probe response.
665 	 */
666 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
667 	    (ieee80211_is_data(hdr->frame_control) ||
668 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
669 		txrc.short_preamble = true;
670 
671 	info->control.short_preamble = txrc.short_preamble;
672 
673 	if (tx->sta)
674 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
675 
676 	/*
677 	 * Lets not bother rate control if we're associated and cannot
678 	 * talk to the sta. This should not happen.
679 	 */
680 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
681 		 !rate_usable_index_exists(sband, &tx->sta->sta),
682 		 "%s: Dropped data frame as no usable bitrate found while "
683 		 "scanning and associated. Target station: "
684 		 "%pM on %d GHz band\n",
685 		 tx->sdata->name, hdr->addr1,
686 		 info->band ? 5 : 2))
687 		return TX_DROP;
688 
689 	/*
690 	 * If we're associated with the sta at this point we know we can at
691 	 * least send the frame at the lowest bit rate.
692 	 */
693 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
694 
695 	if (tx->sta && !info->control.skip_table)
696 		ratetbl = rcu_dereference(tx->sta->sta.rates);
697 
698 	if (unlikely(info->control.rates[0].idx < 0)) {
699 		if (ratetbl) {
700 			struct ieee80211_tx_rate rate = {
701 				.idx = ratetbl->rate[0].idx,
702 				.flags = ratetbl->rate[0].flags,
703 				.count = ratetbl->rate[0].count
704 			};
705 
706 			if (ratetbl->rate[0].idx < 0)
707 				return TX_DROP;
708 
709 			tx->rate = rate;
710 		} else {
711 			return TX_DROP;
712 		}
713 	} else {
714 		tx->rate = info->control.rates[0];
715 	}
716 
717 	if (txrc.reported_rate.idx < 0) {
718 		txrc.reported_rate = tx->rate;
719 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
720 			tx->sta->last_tx_rate = txrc.reported_rate;
721 	} else if (tx->sta)
722 		tx->sta->last_tx_rate = txrc.reported_rate;
723 
724 	if (ratetbl)
725 		return TX_CONTINUE;
726 
727 	if (unlikely(!info->control.rates[0].count))
728 		info->control.rates[0].count = 1;
729 
730 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
731 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
732 		info->control.rates[0].count = 1;
733 
734 	return TX_CONTINUE;
735 }
736 
737 static ieee80211_tx_result debug_noinline
738 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
739 {
740 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
741 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
742 	u16 *seq;
743 	u8 *qc;
744 	int tid;
745 
746 	/*
747 	 * Packet injection may want to control the sequence
748 	 * number, if we have no matching interface then we
749 	 * neither assign one ourselves nor ask the driver to.
750 	 */
751 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
752 		return TX_CONTINUE;
753 
754 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
755 		return TX_CONTINUE;
756 
757 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
758 		return TX_CONTINUE;
759 
760 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
761 		return TX_CONTINUE;
762 
763 	/*
764 	 * Anything but QoS data that has a sequence number field
765 	 * (is long enough) gets a sequence number from the global
766 	 * counter.
767 	 */
768 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
769 		/* driver should assign sequence number */
770 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
771 		/* for pure STA mode without beacons, we can do it */
772 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
773 		tx->sdata->sequence_number += 0x10;
774 		return TX_CONTINUE;
775 	}
776 
777 	/*
778 	 * This should be true for injected/management frames only, for
779 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
780 	 * above since they are not QoS-data frames.
781 	 */
782 	if (!tx->sta)
783 		return TX_CONTINUE;
784 
785 	/* include per-STA, per-TID sequence counter */
786 
787 	qc = ieee80211_get_qos_ctl(hdr);
788 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
789 	seq = &tx->sta->tid_seq[tid];
790 
791 	hdr->seq_ctrl = cpu_to_le16(*seq);
792 
793 	/* Increase the sequence number. */
794 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
795 
796 	return TX_CONTINUE;
797 }
798 
799 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
800 			      struct sk_buff *skb, int hdrlen,
801 			      int frag_threshold)
802 {
803 	struct ieee80211_local *local = tx->local;
804 	struct ieee80211_tx_info *info;
805 	struct sk_buff *tmp;
806 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
807 	int pos = hdrlen + per_fragm;
808 	int rem = skb->len - hdrlen - per_fragm;
809 
810 	if (WARN_ON(rem < 0))
811 		return -EINVAL;
812 
813 	/* first fragment was already added to queue by caller */
814 
815 	while (rem) {
816 		int fraglen = per_fragm;
817 
818 		if (fraglen > rem)
819 			fraglen = rem;
820 		rem -= fraglen;
821 		tmp = dev_alloc_skb(local->tx_headroom +
822 				    frag_threshold +
823 				    IEEE80211_ENCRYPT_HEADROOM +
824 				    IEEE80211_ENCRYPT_TAILROOM);
825 		if (!tmp)
826 			return -ENOMEM;
827 
828 		__skb_queue_tail(&tx->skbs, tmp);
829 
830 		skb_reserve(tmp, local->tx_headroom +
831 				 IEEE80211_ENCRYPT_HEADROOM);
832 		/* copy control information */
833 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
834 
835 		info = IEEE80211_SKB_CB(tmp);
836 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
837 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
838 
839 		if (rem)
840 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
841 
842 		skb_copy_queue_mapping(tmp, skb);
843 		tmp->priority = skb->priority;
844 		tmp->dev = skb->dev;
845 
846 		/* copy header and data */
847 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
848 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
849 
850 		pos += fraglen;
851 	}
852 
853 	/* adjust first fragment's length */
854 	skb->len = hdrlen + per_fragm;
855 	return 0;
856 }
857 
858 static ieee80211_tx_result debug_noinline
859 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
860 {
861 	struct sk_buff *skb = tx->skb;
862 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
863 	struct ieee80211_hdr *hdr = (void *)skb->data;
864 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
865 	int hdrlen;
866 	int fragnum;
867 
868 	/* no matter what happens, tx->skb moves to tx->skbs */
869 	__skb_queue_tail(&tx->skbs, skb);
870 	tx->skb = NULL;
871 
872 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
873 		return TX_CONTINUE;
874 
875 	if (tx->local->ops->set_frag_threshold)
876 		return TX_CONTINUE;
877 
878 	/*
879 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
880 	 * This scenario is handled in ieee80211_tx_prepare but extra
881 	 * caution taken here as fragmented ampdu may cause Tx stop.
882 	 */
883 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
884 		return TX_DROP;
885 
886 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
887 
888 	/* internal error, why isn't DONTFRAG set? */
889 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
890 		return TX_DROP;
891 
892 	/*
893 	 * Now fragment the frame. This will allocate all the fragments and
894 	 * chain them (using skb as the first fragment) to skb->next.
895 	 * During transmission, we will remove the successfully transmitted
896 	 * fragments from this list. When the low-level driver rejects one
897 	 * of the fragments then we will simply pretend to accept the skb
898 	 * but store it away as pending.
899 	 */
900 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
901 		return TX_DROP;
902 
903 	/* update duration/seq/flags of fragments */
904 	fragnum = 0;
905 
906 	skb_queue_walk(&tx->skbs, skb) {
907 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
908 
909 		hdr = (void *)skb->data;
910 		info = IEEE80211_SKB_CB(skb);
911 
912 		if (!skb_queue_is_last(&tx->skbs, skb)) {
913 			hdr->frame_control |= morefrags;
914 			/*
915 			 * No multi-rate retries for fragmented frames, that
916 			 * would completely throw off the NAV at other STAs.
917 			 */
918 			info->control.rates[1].idx = -1;
919 			info->control.rates[2].idx = -1;
920 			info->control.rates[3].idx = -1;
921 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
922 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
923 		} else {
924 			hdr->frame_control &= ~morefrags;
925 		}
926 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
927 		fragnum++;
928 	}
929 
930 	return TX_CONTINUE;
931 }
932 
933 static ieee80211_tx_result debug_noinline
934 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
935 {
936 	struct sk_buff *skb;
937 	int ac = -1;
938 
939 	if (!tx->sta)
940 		return TX_CONTINUE;
941 
942 	skb_queue_walk(&tx->skbs, skb) {
943 		ac = skb_get_queue_mapping(skb);
944 		tx->sta->tx_fragments++;
945 		tx->sta->tx_bytes[ac] += skb->len;
946 	}
947 	if (ac >= 0)
948 		tx->sta->tx_packets[ac]++;
949 
950 	return TX_CONTINUE;
951 }
952 
953 static ieee80211_tx_result debug_noinline
954 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
955 {
956 	if (!tx->key)
957 		return TX_CONTINUE;
958 
959 	switch (tx->key->conf.cipher) {
960 	case WLAN_CIPHER_SUITE_WEP40:
961 	case WLAN_CIPHER_SUITE_WEP104:
962 		return ieee80211_crypto_wep_encrypt(tx);
963 	case WLAN_CIPHER_SUITE_TKIP:
964 		return ieee80211_crypto_tkip_encrypt(tx);
965 	case WLAN_CIPHER_SUITE_CCMP:
966 		return ieee80211_crypto_ccmp_encrypt(tx);
967 	case WLAN_CIPHER_SUITE_AES_CMAC:
968 		return ieee80211_crypto_aes_cmac_encrypt(tx);
969 	default:
970 		return ieee80211_crypto_hw_encrypt(tx);
971 	}
972 
973 	return TX_DROP;
974 }
975 
976 static ieee80211_tx_result debug_noinline
977 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
978 {
979 	struct sk_buff *skb;
980 	struct ieee80211_hdr *hdr;
981 	int next_len;
982 	bool group_addr;
983 
984 	skb_queue_walk(&tx->skbs, skb) {
985 		hdr = (void *) skb->data;
986 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
987 			break; /* must not overwrite AID */
988 		if (!skb_queue_is_last(&tx->skbs, skb)) {
989 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
990 			next_len = next->len;
991 		} else
992 			next_len = 0;
993 		group_addr = is_multicast_ether_addr(hdr->addr1);
994 
995 		hdr->duration_id =
996 			ieee80211_duration(tx, skb, group_addr, next_len);
997 	}
998 
999 	return TX_CONTINUE;
1000 }
1001 
1002 /* actual transmit path */
1003 
1004 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1005 				  struct sk_buff *skb,
1006 				  struct ieee80211_tx_info *info,
1007 				  struct tid_ampdu_tx *tid_tx,
1008 				  int tid)
1009 {
1010 	bool queued = false;
1011 	bool reset_agg_timer = false;
1012 	struct sk_buff *purge_skb = NULL;
1013 
1014 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1015 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1016 		reset_agg_timer = true;
1017 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1018 		/*
1019 		 * nothing -- this aggregation session is being started
1020 		 * but that might still fail with the driver
1021 		 */
1022 	} else {
1023 		spin_lock(&tx->sta->lock);
1024 		/*
1025 		 * Need to re-check now, because we may get here
1026 		 *
1027 		 *  1) in the window during which the setup is actually
1028 		 *     already done, but not marked yet because not all
1029 		 *     packets are spliced over to the driver pending
1030 		 *     queue yet -- if this happened we acquire the lock
1031 		 *     either before or after the splice happens, but
1032 		 *     need to recheck which of these cases happened.
1033 		 *
1034 		 *  2) during session teardown, if the OPERATIONAL bit
1035 		 *     was cleared due to the teardown but the pointer
1036 		 *     hasn't been assigned NULL yet (or we loaded it
1037 		 *     before it was assigned) -- in this case it may
1038 		 *     now be NULL which means we should just let the
1039 		 *     packet pass through because splicing the frames
1040 		 *     back is already done.
1041 		 */
1042 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1043 
1044 		if (!tid_tx) {
1045 			/* do nothing, let packet pass through */
1046 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1047 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1048 			reset_agg_timer = true;
1049 		} else {
1050 			queued = true;
1051 			info->control.vif = &tx->sdata->vif;
1052 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1053 			__skb_queue_tail(&tid_tx->pending, skb);
1054 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1055 				purge_skb = __skb_dequeue(&tid_tx->pending);
1056 		}
1057 		spin_unlock(&tx->sta->lock);
1058 
1059 		if (purge_skb)
1060 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1061 	}
1062 
1063 	/* reset session timer */
1064 	if (reset_agg_timer && tid_tx->timeout)
1065 		tid_tx->last_tx = jiffies;
1066 
1067 	return queued;
1068 }
1069 
1070 /*
1071  * initialises @tx
1072  */
1073 static ieee80211_tx_result
1074 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1075 		     struct ieee80211_tx_data *tx,
1076 		     struct sk_buff *skb)
1077 {
1078 	struct ieee80211_local *local = sdata->local;
1079 	struct ieee80211_hdr *hdr;
1080 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1081 	int tid;
1082 	u8 *qc;
1083 
1084 	memset(tx, 0, sizeof(*tx));
1085 	tx->skb = skb;
1086 	tx->local = local;
1087 	tx->sdata = sdata;
1088 	__skb_queue_head_init(&tx->skbs);
1089 
1090 	/*
1091 	 * If this flag is set to true anywhere, and we get here,
1092 	 * we are doing the needed processing, so remove the flag
1093 	 * now.
1094 	 */
1095 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1096 
1097 	hdr = (struct ieee80211_hdr *) skb->data;
1098 
1099 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1100 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1101 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1102 			return TX_DROP;
1103 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED ||
1104 		   tx->sdata->control_port_protocol == tx->skb->protocol) {
1105 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1106 	}
1107 	if (!tx->sta)
1108 		tx->sta = sta_info_get(sdata, hdr->addr1);
1109 
1110 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1111 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1112 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1113 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1114 		struct tid_ampdu_tx *tid_tx;
1115 
1116 		qc = ieee80211_get_qos_ctl(hdr);
1117 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1118 
1119 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1120 		if (tid_tx) {
1121 			bool queued;
1122 
1123 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1124 						       tid_tx, tid);
1125 
1126 			if (unlikely(queued))
1127 				return TX_QUEUED;
1128 		}
1129 	}
1130 
1131 	if (is_multicast_ether_addr(hdr->addr1)) {
1132 		tx->flags &= ~IEEE80211_TX_UNICAST;
1133 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1134 	} else
1135 		tx->flags |= IEEE80211_TX_UNICAST;
1136 
1137 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1138 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1139 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1140 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1141 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1142 	}
1143 
1144 	if (!tx->sta)
1145 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1146 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1147 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1148 
1149 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1150 
1151 	return TX_CONTINUE;
1152 }
1153 
1154 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1155 			       struct ieee80211_vif *vif,
1156 			       struct ieee80211_sta *sta,
1157 			       struct sk_buff_head *skbs,
1158 			       bool txpending)
1159 {
1160 	struct ieee80211_tx_control control;
1161 	struct sk_buff *skb, *tmp;
1162 	unsigned long flags;
1163 
1164 	skb_queue_walk_safe(skbs, skb, tmp) {
1165 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1166 		int q = info->hw_queue;
1167 
1168 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1169 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1170 			__skb_unlink(skb, skbs);
1171 			ieee80211_free_txskb(&local->hw, skb);
1172 			continue;
1173 		}
1174 #endif
1175 
1176 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1177 		if (local->queue_stop_reasons[q] ||
1178 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1179 			if (unlikely(info->flags &
1180 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1181 				if (local->queue_stop_reasons[q] &
1182 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1183 					/*
1184 					 * Drop off-channel frames if queues
1185 					 * are stopped for any reason other
1186 					 * than off-channel operation. Never
1187 					 * queue them.
1188 					 */
1189 					spin_unlock_irqrestore(
1190 						&local->queue_stop_reason_lock,
1191 						flags);
1192 					ieee80211_purge_tx_queue(&local->hw,
1193 								 skbs);
1194 					return true;
1195 				}
1196 			} else {
1197 
1198 				/*
1199 				 * Since queue is stopped, queue up frames for
1200 				 * later transmission from the tx-pending
1201 				 * tasklet when the queue is woken again.
1202 				 */
1203 				if (txpending)
1204 					skb_queue_splice_init(skbs,
1205 							      &local->pending[q]);
1206 				else
1207 					skb_queue_splice_tail_init(skbs,
1208 								   &local->pending[q]);
1209 
1210 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1211 						       flags);
1212 				return false;
1213 			}
1214 		}
1215 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1216 
1217 		info->control.vif = vif;
1218 		control.sta = sta;
1219 
1220 		__skb_unlink(skb, skbs);
1221 		drv_tx(local, &control, skb);
1222 	}
1223 
1224 	return true;
1225 }
1226 
1227 /*
1228  * Returns false if the frame couldn't be transmitted but was queued instead.
1229  */
1230 static bool __ieee80211_tx(struct ieee80211_local *local,
1231 			   struct sk_buff_head *skbs, int led_len,
1232 			   struct sta_info *sta, bool txpending)
1233 {
1234 	struct ieee80211_tx_info *info;
1235 	struct ieee80211_sub_if_data *sdata;
1236 	struct ieee80211_vif *vif;
1237 	struct ieee80211_sta *pubsta;
1238 	struct sk_buff *skb;
1239 	bool result = true;
1240 	__le16 fc;
1241 
1242 	if (WARN_ON(skb_queue_empty(skbs)))
1243 		return true;
1244 
1245 	skb = skb_peek(skbs);
1246 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1247 	info = IEEE80211_SKB_CB(skb);
1248 	sdata = vif_to_sdata(info->control.vif);
1249 	if (sta && !sta->uploaded)
1250 		sta = NULL;
1251 
1252 	if (sta)
1253 		pubsta = &sta->sta;
1254 	else
1255 		pubsta = NULL;
1256 
1257 	switch (sdata->vif.type) {
1258 	case NL80211_IFTYPE_MONITOR:
1259 		sdata = rcu_dereference(local->monitor_sdata);
1260 		if (sdata) {
1261 			vif = &sdata->vif;
1262 			info->hw_queue =
1263 				vif->hw_queue[skb_get_queue_mapping(skb)];
1264 		} else if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL) {
1265 			dev_kfree_skb(skb);
1266 			return true;
1267 		} else
1268 			vif = NULL;
1269 		break;
1270 	case NL80211_IFTYPE_AP_VLAN:
1271 		sdata = container_of(sdata->bss,
1272 				     struct ieee80211_sub_if_data, u.ap);
1273 		/* fall through */
1274 	default:
1275 		vif = &sdata->vif;
1276 		break;
1277 	}
1278 
1279 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1280 				    txpending);
1281 
1282 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1283 	ieee80211_led_tx(local, 1);
1284 
1285 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1286 
1287 	return result;
1288 }
1289 
1290 /*
1291  * Invoke TX handlers, return 0 on success and non-zero if the
1292  * frame was dropped or queued.
1293  */
1294 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1295 {
1296 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1297 	ieee80211_tx_result res = TX_DROP;
1298 
1299 #define CALL_TXH(txh) \
1300 	do {				\
1301 		res = txh(tx);		\
1302 		if (res != TX_CONTINUE)	\
1303 			goto txh_done;	\
1304 	} while (0)
1305 
1306 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1307 	CALL_TXH(ieee80211_tx_h_check_assoc);
1308 	CALL_TXH(ieee80211_tx_h_ps_buf);
1309 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1310 	CALL_TXH(ieee80211_tx_h_select_key);
1311 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1312 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1313 
1314 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1315 		__skb_queue_tail(&tx->skbs, tx->skb);
1316 		tx->skb = NULL;
1317 		goto txh_done;
1318 	}
1319 
1320 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1321 	CALL_TXH(ieee80211_tx_h_sequence);
1322 	CALL_TXH(ieee80211_tx_h_fragment);
1323 	/* handlers after fragment must be aware of tx info fragmentation! */
1324 	CALL_TXH(ieee80211_tx_h_stats);
1325 	CALL_TXH(ieee80211_tx_h_encrypt);
1326 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1327 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1328 #undef CALL_TXH
1329 
1330  txh_done:
1331 	if (unlikely(res == TX_DROP)) {
1332 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1333 		if (tx->skb)
1334 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1335 		else
1336 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1337 		return -1;
1338 	} else if (unlikely(res == TX_QUEUED)) {
1339 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1340 		return -1;
1341 	}
1342 
1343 	return 0;
1344 }
1345 
1346 /*
1347  * Returns false if the frame couldn't be transmitted but was queued instead.
1348  */
1349 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1350 			 struct sk_buff *skb, bool txpending,
1351 			 enum ieee80211_band band)
1352 {
1353 	struct ieee80211_local *local = sdata->local;
1354 	struct ieee80211_tx_data tx;
1355 	ieee80211_tx_result res_prepare;
1356 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1357 	bool result = true;
1358 	int led_len;
1359 
1360 	if (unlikely(skb->len < 10)) {
1361 		dev_kfree_skb(skb);
1362 		return true;
1363 	}
1364 
1365 	/* initialises tx */
1366 	led_len = skb->len;
1367 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1368 
1369 	if (unlikely(res_prepare == TX_DROP)) {
1370 		ieee80211_free_txskb(&local->hw, skb);
1371 		return true;
1372 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1373 		return true;
1374 	}
1375 
1376 	info->band = band;
1377 
1378 	/* set up hw_queue value early */
1379 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1380 	    !(local->hw.flags & IEEE80211_HW_QUEUE_CONTROL))
1381 		info->hw_queue =
1382 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1383 
1384 	if (!invoke_tx_handlers(&tx))
1385 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1386 					tx.sta, txpending);
1387 
1388 	return result;
1389 }
1390 
1391 /* device xmit handlers */
1392 
1393 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1394 				struct sk_buff *skb,
1395 				int head_need, bool may_encrypt)
1396 {
1397 	struct ieee80211_local *local = sdata->local;
1398 	int tail_need = 0;
1399 
1400 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1401 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1402 		tail_need -= skb_tailroom(skb);
1403 		tail_need = max_t(int, tail_need, 0);
1404 	}
1405 
1406 	if (skb_cloned(skb))
1407 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1408 	else if (head_need || tail_need)
1409 		I802_DEBUG_INC(local->tx_expand_skb_head);
1410 	else
1411 		return 0;
1412 
1413 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1414 		wiphy_debug(local->hw.wiphy,
1415 			    "failed to reallocate TX buffer\n");
1416 		return -ENOMEM;
1417 	}
1418 
1419 	return 0;
1420 }
1421 
1422 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
1423 		    enum ieee80211_band band)
1424 {
1425 	struct ieee80211_local *local = sdata->local;
1426 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1427 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1428 	int headroom;
1429 	bool may_encrypt;
1430 
1431 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1432 
1433 	headroom = local->tx_headroom;
1434 	if (may_encrypt)
1435 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1436 	headroom -= skb_headroom(skb);
1437 	headroom = max_t(int, 0, headroom);
1438 
1439 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1440 		ieee80211_free_txskb(&local->hw, skb);
1441 		return;
1442 	}
1443 
1444 	hdr = (struct ieee80211_hdr *) skb->data;
1445 	info->control.vif = &sdata->vif;
1446 
1447 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1448 		if (ieee80211_is_data(hdr->frame_control) &&
1449 		    is_unicast_ether_addr(hdr->addr1)) {
1450 			if (mesh_nexthop_resolve(sdata, skb))
1451 				return; /* skb queued: don't free */
1452 		} else {
1453 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1454 		}
1455 	}
1456 
1457 	ieee80211_set_qos_hdr(sdata, skb);
1458 	ieee80211_tx(sdata, skb, false, band);
1459 }
1460 
1461 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1462 {
1463 	struct ieee80211_radiotap_iterator iterator;
1464 	struct ieee80211_radiotap_header *rthdr =
1465 		(struct ieee80211_radiotap_header *) skb->data;
1466 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1467 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1468 						   NULL);
1469 	u16 txflags;
1470 
1471 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1472 		       IEEE80211_TX_CTL_DONTFRAG;
1473 
1474 	/*
1475 	 * for every radiotap entry that is present
1476 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1477 	 * entries present, or -EINVAL on error)
1478 	 */
1479 
1480 	while (!ret) {
1481 		ret = ieee80211_radiotap_iterator_next(&iterator);
1482 
1483 		if (ret)
1484 			continue;
1485 
1486 		/* see if this argument is something we can use */
1487 		switch (iterator.this_arg_index) {
1488 		/*
1489 		 * You must take care when dereferencing iterator.this_arg
1490 		 * for multibyte types... the pointer is not aligned.  Use
1491 		 * get_unaligned((type *)iterator.this_arg) to dereference
1492 		 * iterator.this_arg for type "type" safely on all arches.
1493 		*/
1494 		case IEEE80211_RADIOTAP_FLAGS:
1495 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1496 				/*
1497 				 * this indicates that the skb we have been
1498 				 * handed has the 32-bit FCS CRC at the end...
1499 				 * we should react to that by snipping it off
1500 				 * because it will be recomputed and added
1501 				 * on transmission
1502 				 */
1503 				if (skb->len < (iterator._max_length + FCS_LEN))
1504 					return false;
1505 
1506 				skb_trim(skb, skb->len - FCS_LEN);
1507 			}
1508 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1509 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1510 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1511 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1512 			break;
1513 
1514 		case IEEE80211_RADIOTAP_TX_FLAGS:
1515 			txflags = get_unaligned_le16(iterator.this_arg);
1516 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1517 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1518 			break;
1519 
1520 		/*
1521 		 * Please update the file
1522 		 * Documentation/networking/mac80211-injection.txt
1523 		 * when parsing new fields here.
1524 		 */
1525 
1526 		default:
1527 			break;
1528 		}
1529 	}
1530 
1531 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1532 		return false;
1533 
1534 	/*
1535 	 * remove the radiotap header
1536 	 * iterator->_max_length was sanity-checked against
1537 	 * skb->len by iterator init
1538 	 */
1539 	skb_pull(skb, iterator._max_length);
1540 
1541 	return true;
1542 }
1543 
1544 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1545 					 struct net_device *dev)
1546 {
1547 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1548 	struct ieee80211_chanctx_conf *chanctx_conf;
1549 	struct ieee80211_channel *chan;
1550 	struct ieee80211_radiotap_header *prthdr =
1551 		(struct ieee80211_radiotap_header *)skb->data;
1552 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1553 	struct ieee80211_hdr *hdr;
1554 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1555 	u16 len_rthdr;
1556 	int hdrlen;
1557 
1558 	/* check for not even having the fixed radiotap header part */
1559 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1560 		goto fail; /* too short to be possibly valid */
1561 
1562 	/* is it a header version we can trust to find length from? */
1563 	if (unlikely(prthdr->it_version))
1564 		goto fail; /* only version 0 is supported */
1565 
1566 	/* then there must be a radiotap header with a length we can use */
1567 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1568 
1569 	/* does the skb contain enough to deliver on the alleged length? */
1570 	if (unlikely(skb->len < len_rthdr))
1571 		goto fail; /* skb too short for claimed rt header extent */
1572 
1573 	/*
1574 	 * fix up the pointers accounting for the radiotap
1575 	 * header still being in there.  We are being given
1576 	 * a precooked IEEE80211 header so no need for
1577 	 * normal processing
1578 	 */
1579 	skb_set_mac_header(skb, len_rthdr);
1580 	/*
1581 	 * these are just fixed to the end of the rt area since we
1582 	 * don't have any better information and at this point, nobody cares
1583 	 */
1584 	skb_set_network_header(skb, len_rthdr);
1585 	skb_set_transport_header(skb, len_rthdr);
1586 
1587 	if (skb->len < len_rthdr + 2)
1588 		goto fail;
1589 
1590 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1591 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1592 
1593 	if (skb->len < len_rthdr + hdrlen)
1594 		goto fail;
1595 
1596 	/*
1597 	 * Initialize skb->protocol if the injected frame is a data frame
1598 	 * carrying a rfc1042 header
1599 	 */
1600 	if (ieee80211_is_data(hdr->frame_control) &&
1601 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1602 		u8 *payload = (u8 *)hdr + hdrlen;
1603 
1604 		if (ether_addr_equal(payload, rfc1042_header))
1605 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1606 						    payload[7]);
1607 	}
1608 
1609 	memset(info, 0, sizeof(*info));
1610 
1611 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1612 		      IEEE80211_TX_CTL_INJECTED;
1613 
1614 	/* process and remove the injection radiotap header */
1615 	if (!ieee80211_parse_tx_radiotap(skb))
1616 		goto fail;
1617 
1618 	rcu_read_lock();
1619 
1620 	/*
1621 	 * We process outgoing injected frames that have a local address
1622 	 * we handle as though they are non-injected frames.
1623 	 * This code here isn't entirely correct, the local MAC address
1624 	 * isn't always enough to find the interface to use; for proper
1625 	 * VLAN/WDS support we will need a different mechanism (which
1626 	 * likely isn't going to be monitor interfaces).
1627 	 */
1628 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1629 
1630 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1631 		if (!ieee80211_sdata_running(tmp_sdata))
1632 			continue;
1633 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1634 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1635 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1636 			continue;
1637 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1638 			sdata = tmp_sdata;
1639 			break;
1640 		}
1641 	}
1642 
1643 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1644 	if (!chanctx_conf) {
1645 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1646 		if (tmp_sdata)
1647 			chanctx_conf =
1648 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1649 	}
1650 
1651 	if (chanctx_conf)
1652 		chan = chanctx_conf->def.chan;
1653 	else if (!local->use_chanctx)
1654 		chan = local->_oper_chandef.chan;
1655 	else
1656 		goto fail_rcu;
1657 
1658 	/*
1659 	 * Frame injection is not allowed if beaconing is not allowed
1660 	 * or if we need radar detection. Beaconing is usually not allowed when
1661 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1662 	 * Passive scan is also used in world regulatory domains where
1663 	 * your country is not known and as such it should be treated as
1664 	 * NO TX unless the channel is explicitly allowed in which case
1665 	 * your current regulatory domain would not have the passive scan
1666 	 * flag.
1667 	 *
1668 	 * Since AP mode uses monitor interfaces to inject/TX management
1669 	 * frames we can make AP mode the exception to this rule once it
1670 	 * supports radar detection as its implementation can deal with
1671 	 * radar detection by itself. We can do that later by adding a
1672 	 * monitor flag interfaces used for AP support.
1673 	 */
1674 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1675 			    IEEE80211_CHAN_PASSIVE_SCAN)))
1676 		goto fail_rcu;
1677 
1678 	ieee80211_xmit(sdata, skb, chan->band);
1679 	rcu_read_unlock();
1680 
1681 	return NETDEV_TX_OK;
1682 
1683 fail_rcu:
1684 	rcu_read_unlock();
1685 fail:
1686 	dev_kfree_skb(skb);
1687 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1688 }
1689 
1690 /**
1691  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1692  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1693  * @skb: packet to be sent
1694  * @dev: incoming interface
1695  *
1696  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1697  * not be freed, and caller is responsible for either retrying later or freeing
1698  * skb).
1699  *
1700  * This function takes in an Ethernet header and encapsulates it with suitable
1701  * IEEE 802.11 header based on which interface the packet is coming in. The
1702  * encapsulated packet will then be passed to master interface, wlan#.11, for
1703  * transmission (through low-level driver).
1704  */
1705 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1706 				    struct net_device *dev)
1707 {
1708 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1709 	struct ieee80211_local *local = sdata->local;
1710 	struct ieee80211_tx_info *info;
1711 	int head_need;
1712 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1713 	__le16 fc;
1714 	struct ieee80211_hdr hdr;
1715 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1716 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
1717 	const u8 *encaps_data;
1718 	int encaps_len, skip_header_bytes;
1719 	int nh_pos, h_pos;
1720 	struct sta_info *sta = NULL;
1721 	bool wme_sta = false, authorized = false, tdls_auth = false;
1722 	bool tdls_direct = false;
1723 	bool multicast;
1724 	u32 info_flags = 0;
1725 	u16 info_id = 0;
1726 	struct ieee80211_chanctx_conf *chanctx_conf;
1727 	struct ieee80211_sub_if_data *ap_sdata;
1728 	enum ieee80211_band band;
1729 
1730 	if (unlikely(skb->len < ETH_HLEN))
1731 		goto fail;
1732 
1733 	/* convert Ethernet header to proper 802.11 header (based on
1734 	 * operation mode) */
1735 	ethertype = (skb->data[12] << 8) | skb->data[13];
1736 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1737 
1738 	rcu_read_lock();
1739 
1740 	switch (sdata->vif.type) {
1741 	case NL80211_IFTYPE_AP_VLAN:
1742 		sta = rcu_dereference(sdata->u.vlan.sta);
1743 		if (sta) {
1744 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1745 			/* RA TA DA SA */
1746 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1747 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1748 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1749 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1750 			hdrlen = 30;
1751 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1752 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1753 		}
1754 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1755 					u.ap);
1756 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
1757 		if (!chanctx_conf)
1758 			goto fail_rcu;
1759 		band = chanctx_conf->def.chan->band;
1760 		if (sta)
1761 			break;
1762 		/* fall through */
1763 	case NL80211_IFTYPE_AP:
1764 		if (sdata->vif.type == NL80211_IFTYPE_AP)
1765 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1766 		if (!chanctx_conf)
1767 			goto fail_rcu;
1768 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1769 		/* DA BSSID SA */
1770 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1771 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1772 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1773 		hdrlen = 24;
1774 		band = chanctx_conf->def.chan->band;
1775 		break;
1776 	case NL80211_IFTYPE_WDS:
1777 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1778 		/* RA TA DA SA */
1779 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1780 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1781 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1782 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1783 		hdrlen = 30;
1784 		/*
1785 		 * This is the exception! WDS style interfaces are prohibited
1786 		 * when channel contexts are in used so this must be valid
1787 		 */
1788 		band = local->hw.conf.chandef.chan->band;
1789 		break;
1790 #ifdef CONFIG_MAC80211_MESH
1791 	case NL80211_IFTYPE_MESH_POINT:
1792 		if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1793 			/* Do not send frames with mesh_ttl == 0 */
1794 			sdata->u.mesh.mshstats.dropped_frames_ttl++;
1795 			goto fail_rcu;
1796 		}
1797 
1798 		if (!is_multicast_ether_addr(skb->data)) {
1799 			struct sta_info *next_hop;
1800 			bool mpp_lookup = true;
1801 
1802 			mpath = mesh_path_lookup(sdata, skb->data);
1803 			if (mpath) {
1804 				mpp_lookup = false;
1805 				next_hop = rcu_dereference(mpath->next_hop);
1806 				if (!next_hop ||
1807 				    !(mpath->flags & (MESH_PATH_ACTIVE |
1808 						      MESH_PATH_RESOLVING)))
1809 					mpp_lookup = true;
1810 			}
1811 
1812 			if (mpp_lookup)
1813 				mppath = mpp_path_lookup(sdata, skb->data);
1814 
1815 			if (mppath && mpath)
1816 				mesh_path_del(mpath->sdata, mpath->dst);
1817 		}
1818 
1819 		/*
1820 		 * Use address extension if it is a packet from
1821 		 * another interface or if we know the destination
1822 		 * is being proxied by a portal (i.e. portal address
1823 		 * differs from proxied address)
1824 		 */
1825 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
1826 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
1827 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1828 					skb->data, skb->data + ETH_ALEN);
1829 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
1830 							       NULL, NULL);
1831 		} else {
1832 			/* DS -> MBSS (802.11-2012 13.11.3.3).
1833 			 * For unicast with unknown forwarding information,
1834 			 * destination might be in the MBSS or if that fails
1835 			 * forwarded to another mesh gate. In either case
1836 			 * resolution will be handled in ieee80211_xmit(), so
1837 			 * leave the original DA. This also works for mcast */
1838 			const u8 *mesh_da = skb->data;
1839 
1840 			if (mppath)
1841 				mesh_da = mppath->mpp;
1842 			else if (mpath)
1843 				mesh_da = mpath->dst;
1844 
1845 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1846 					mesh_da, sdata->vif.addr);
1847 			if (is_multicast_ether_addr(mesh_da))
1848 				/* DA TA mSA AE:SA */
1849 				meshhdrlen = ieee80211_new_mesh_header(
1850 						sdata, &mesh_hdr,
1851 						skb->data + ETH_ALEN, NULL);
1852 			else
1853 				/* RA TA mDA mSA AE:DA SA */
1854 				meshhdrlen = ieee80211_new_mesh_header(
1855 						sdata, &mesh_hdr, skb->data,
1856 						skb->data + ETH_ALEN);
1857 
1858 		}
1859 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1860 		if (!chanctx_conf)
1861 			goto fail_rcu;
1862 		band = chanctx_conf->def.chan->band;
1863 		break;
1864 #endif
1865 	case NL80211_IFTYPE_STATION:
1866 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1867 			bool tdls_peer = false;
1868 
1869 			sta = sta_info_get(sdata, skb->data);
1870 			if (sta) {
1871 				authorized = test_sta_flag(sta,
1872 							WLAN_STA_AUTHORIZED);
1873 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1874 				tdls_peer = test_sta_flag(sta,
1875 							 WLAN_STA_TDLS_PEER);
1876 				tdls_auth = test_sta_flag(sta,
1877 						WLAN_STA_TDLS_PEER_AUTH);
1878 			}
1879 
1880 			/*
1881 			 * If the TDLS link is enabled, send everything
1882 			 * directly. Otherwise, allow TDLS setup frames
1883 			 * to be transmitted indirectly.
1884 			 */
1885 			tdls_direct = tdls_peer && (tdls_auth ||
1886 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1887 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1888 		}
1889 
1890 		if (tdls_direct) {
1891 			/* link during setup - throw out frames to peer */
1892 			if (!tdls_auth)
1893 				goto fail_rcu;
1894 
1895 			/* DA SA BSSID */
1896 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1897 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1898 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1899 			hdrlen = 24;
1900 		}  else if (sdata->u.mgd.use_4addr &&
1901 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1902 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1903 					  IEEE80211_FCTL_TODS);
1904 			/* RA TA DA SA */
1905 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1906 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1907 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1908 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1909 			hdrlen = 30;
1910 		} else {
1911 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1912 			/* BSSID SA DA */
1913 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1914 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1915 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1916 			hdrlen = 24;
1917 		}
1918 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1919 		if (!chanctx_conf)
1920 			goto fail_rcu;
1921 		band = chanctx_conf->def.chan->band;
1922 		break;
1923 	case NL80211_IFTYPE_ADHOC:
1924 		/* DA SA BSSID */
1925 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1926 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1927 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1928 		hdrlen = 24;
1929 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1930 		if (!chanctx_conf)
1931 			goto fail_rcu;
1932 		band = chanctx_conf->def.chan->band;
1933 		break;
1934 	default:
1935 		goto fail_rcu;
1936 	}
1937 
1938 	/*
1939 	 * There's no need to try to look up the destination
1940 	 * if it is a multicast address (which can only happen
1941 	 * in AP mode)
1942 	 */
1943 	multicast = is_multicast_ether_addr(hdr.addr1);
1944 	if (!multicast) {
1945 		sta = sta_info_get(sdata, hdr.addr1);
1946 		if (sta) {
1947 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1948 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1949 		}
1950 	}
1951 
1952 	/* For mesh, the use of the QoS header is mandatory */
1953 	if (ieee80211_vif_is_mesh(&sdata->vif))
1954 		wme_sta = true;
1955 
1956 	/* receiver and we are QoS enabled, use a QoS type frame */
1957 	if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
1958 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1959 		hdrlen += 2;
1960 	}
1961 
1962 	/*
1963 	 * Drop unicast frames to unauthorised stations unless they are
1964 	 * EAPOL frames from the local station.
1965 	 */
1966 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
1967 		     !is_multicast_ether_addr(hdr.addr1) && !authorized &&
1968 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
1969 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
1970 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1971 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
1972 				    dev->name, hdr.addr1);
1973 #endif
1974 
1975 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1976 
1977 		goto fail_rcu;
1978 	}
1979 
1980 	if (unlikely(!multicast && skb->sk &&
1981 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
1982 		struct sk_buff *orig_skb = skb;
1983 
1984 		skb = skb_clone(skb, GFP_ATOMIC);
1985 		if (skb) {
1986 			unsigned long flags;
1987 			int id;
1988 
1989 			spin_lock_irqsave(&local->ack_status_lock, flags);
1990 			id = idr_alloc(&local->ack_status_frames, orig_skb,
1991 				       1, 0x10000, GFP_ATOMIC);
1992 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
1993 
1994 			if (id >= 0) {
1995 				info_id = id;
1996 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1997 			} else if (skb_shared(skb)) {
1998 				kfree_skb(orig_skb);
1999 			} else {
2000 				kfree_skb(skb);
2001 				skb = orig_skb;
2002 			}
2003 		} else {
2004 			/* couldn't clone -- lose tx status ... */
2005 			skb = orig_skb;
2006 		}
2007 	}
2008 
2009 	/*
2010 	 * If the skb is shared we need to obtain our own copy.
2011 	 */
2012 	if (skb_shared(skb)) {
2013 		struct sk_buff *tmp_skb = skb;
2014 
2015 		/* can't happen -- skb is a clone if info_id != 0 */
2016 		WARN_ON(info_id);
2017 
2018 		skb = skb_clone(skb, GFP_ATOMIC);
2019 		kfree_skb(tmp_skb);
2020 
2021 		if (!skb)
2022 			goto fail_rcu;
2023 	}
2024 
2025 	hdr.frame_control = fc;
2026 	hdr.duration_id = 0;
2027 	hdr.seq_ctrl = 0;
2028 
2029 	skip_header_bytes = ETH_HLEN;
2030 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2031 		encaps_data = bridge_tunnel_header;
2032 		encaps_len = sizeof(bridge_tunnel_header);
2033 		skip_header_bytes -= 2;
2034 	} else if (ethertype >= ETH_P_802_3_MIN) {
2035 		encaps_data = rfc1042_header;
2036 		encaps_len = sizeof(rfc1042_header);
2037 		skip_header_bytes -= 2;
2038 	} else {
2039 		encaps_data = NULL;
2040 		encaps_len = 0;
2041 	}
2042 
2043 	nh_pos = skb_network_header(skb) - skb->data;
2044 	h_pos = skb_transport_header(skb) - skb->data;
2045 
2046 	skb_pull(skb, skip_header_bytes);
2047 	nh_pos -= skip_header_bytes;
2048 	h_pos -= skip_header_bytes;
2049 
2050 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2051 
2052 	/*
2053 	 * So we need to modify the skb header and hence need a copy of
2054 	 * that. The head_need variable above doesn't, so far, include
2055 	 * the needed header space that we don't need right away. If we
2056 	 * can, then we don't reallocate right now but only after the
2057 	 * frame arrives at the master device (if it does...)
2058 	 *
2059 	 * If we cannot, however, then we will reallocate to include all
2060 	 * the ever needed space. Also, if we need to reallocate it anyway,
2061 	 * make it big enough for everything we may ever need.
2062 	 */
2063 
2064 	if (head_need > 0 || skb_cloned(skb)) {
2065 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2066 		head_need += local->tx_headroom;
2067 		head_need = max_t(int, 0, head_need);
2068 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2069 			ieee80211_free_txskb(&local->hw, skb);
2070 			skb = NULL;
2071 			goto fail_rcu;
2072 		}
2073 	}
2074 
2075 	if (encaps_data) {
2076 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2077 		nh_pos += encaps_len;
2078 		h_pos += encaps_len;
2079 	}
2080 
2081 #ifdef CONFIG_MAC80211_MESH
2082 	if (meshhdrlen > 0) {
2083 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2084 		nh_pos += meshhdrlen;
2085 		h_pos += meshhdrlen;
2086 	}
2087 #endif
2088 
2089 	if (ieee80211_is_data_qos(fc)) {
2090 		__le16 *qos_control;
2091 
2092 		qos_control = (__le16*) skb_push(skb, 2);
2093 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2094 		/*
2095 		 * Maybe we could actually set some fields here, for now just
2096 		 * initialise to zero to indicate no special operation.
2097 		 */
2098 		*qos_control = 0;
2099 	} else
2100 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2101 
2102 	nh_pos += hdrlen;
2103 	h_pos += hdrlen;
2104 
2105 	dev->stats.tx_packets++;
2106 	dev->stats.tx_bytes += skb->len;
2107 
2108 	/* Update skb pointers to various headers since this modified frame
2109 	 * is going to go through Linux networking code that may potentially
2110 	 * need things like pointer to IP header. */
2111 	skb_set_mac_header(skb, 0);
2112 	skb_set_network_header(skb, nh_pos);
2113 	skb_set_transport_header(skb, h_pos);
2114 
2115 	info = IEEE80211_SKB_CB(skb);
2116 	memset(info, 0, sizeof(*info));
2117 
2118 	dev->trans_start = jiffies;
2119 
2120 	info->flags = info_flags;
2121 	info->ack_frame_id = info_id;
2122 
2123 	ieee80211_xmit(sdata, skb, band);
2124 	rcu_read_unlock();
2125 
2126 	return NETDEV_TX_OK;
2127 
2128  fail_rcu:
2129 	rcu_read_unlock();
2130  fail:
2131 	dev_kfree_skb(skb);
2132 	return NETDEV_TX_OK;
2133 }
2134 
2135 
2136 /*
2137  * ieee80211_clear_tx_pending may not be called in a context where
2138  * it is possible that it packets could come in again.
2139  */
2140 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2141 {
2142 	struct sk_buff *skb;
2143 	int i;
2144 
2145 	for (i = 0; i < local->hw.queues; i++) {
2146 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
2147 			ieee80211_free_txskb(&local->hw, skb);
2148 	}
2149 }
2150 
2151 /*
2152  * Returns false if the frame couldn't be transmitted but was queued instead,
2153  * which in this case means re-queued -- take as an indication to stop sending
2154  * more pending frames.
2155  */
2156 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2157 				     struct sk_buff *skb)
2158 {
2159 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2160 	struct ieee80211_sub_if_data *sdata;
2161 	struct sta_info *sta;
2162 	struct ieee80211_hdr *hdr;
2163 	bool result;
2164 	struct ieee80211_chanctx_conf *chanctx_conf;
2165 
2166 	sdata = vif_to_sdata(info->control.vif);
2167 
2168 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2169 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2170 		if (unlikely(!chanctx_conf)) {
2171 			dev_kfree_skb(skb);
2172 			return true;
2173 		}
2174 		result = ieee80211_tx(sdata, skb, true,
2175 				      chanctx_conf->def.chan->band);
2176 	} else {
2177 		struct sk_buff_head skbs;
2178 
2179 		__skb_queue_head_init(&skbs);
2180 		__skb_queue_tail(&skbs, skb);
2181 
2182 		hdr = (struct ieee80211_hdr *)skb->data;
2183 		sta = sta_info_get(sdata, hdr->addr1);
2184 
2185 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2186 	}
2187 
2188 	return result;
2189 }
2190 
2191 /*
2192  * Transmit all pending packets. Called from tasklet.
2193  */
2194 void ieee80211_tx_pending(unsigned long data)
2195 {
2196 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2197 	unsigned long flags;
2198 	int i;
2199 	bool txok;
2200 
2201 	rcu_read_lock();
2202 
2203 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2204 	for (i = 0; i < local->hw.queues; i++) {
2205 		/*
2206 		 * If queue is stopped by something other than due to pending
2207 		 * frames, or we have no pending frames, proceed to next queue.
2208 		 */
2209 		if (local->queue_stop_reasons[i] ||
2210 		    skb_queue_empty(&local->pending[i]))
2211 			continue;
2212 
2213 		while (!skb_queue_empty(&local->pending[i])) {
2214 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2215 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2216 
2217 			if (WARN_ON(!info->control.vif)) {
2218 				ieee80211_free_txskb(&local->hw, skb);
2219 				continue;
2220 			}
2221 
2222 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2223 						flags);
2224 
2225 			txok = ieee80211_tx_pending_skb(local, skb);
2226 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2227 					  flags);
2228 			if (!txok)
2229 				break;
2230 		}
2231 
2232 		if (skb_queue_empty(&local->pending[i]))
2233 			ieee80211_propagate_queue_wake(local, i);
2234 	}
2235 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2236 
2237 	rcu_read_unlock();
2238 }
2239 
2240 /* functions for drivers to get certain frames */
2241 
2242 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2243 				       struct ps_data *ps, struct sk_buff *skb)
2244 {
2245 	u8 *pos, *tim;
2246 	int aid0 = 0;
2247 	int i, have_bits = 0, n1, n2;
2248 
2249 	/* Generate bitmap for TIM only if there are any STAs in power save
2250 	 * mode. */
2251 	if (atomic_read(&ps->num_sta_ps) > 0)
2252 		/* in the hope that this is faster than
2253 		 * checking byte-for-byte */
2254 		have_bits = !bitmap_empty((unsigned long*)ps->tim,
2255 					  IEEE80211_MAX_AID+1);
2256 
2257 	if (ps->dtim_count == 0)
2258 		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
2259 	else
2260 		ps->dtim_count--;
2261 
2262 	tim = pos = (u8 *) skb_put(skb, 6);
2263 	*pos++ = WLAN_EID_TIM;
2264 	*pos++ = 4;
2265 	*pos++ = ps->dtim_count;
2266 	*pos++ = sdata->vif.bss_conf.dtim_period;
2267 
2268 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
2269 		aid0 = 1;
2270 
2271 	ps->dtim_bc_mc = aid0 == 1;
2272 
2273 	if (have_bits) {
2274 		/* Find largest even number N1 so that bits numbered 1 through
2275 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2276 		 * (N2 + 1) x 8 through 2007 are 0. */
2277 		n1 = 0;
2278 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2279 			if (ps->tim[i]) {
2280 				n1 = i & 0xfe;
2281 				break;
2282 			}
2283 		}
2284 		n2 = n1;
2285 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2286 			if (ps->tim[i]) {
2287 				n2 = i;
2288 				break;
2289 			}
2290 		}
2291 
2292 		/* Bitmap control */
2293 		*pos++ = n1 | aid0;
2294 		/* Part Virt Bitmap */
2295 		skb_put(skb, n2 - n1);
2296 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
2297 
2298 		tim[1] = n2 - n1 + 4;
2299 	} else {
2300 		*pos++ = aid0; /* Bitmap control */
2301 		*pos++ = 0; /* Part Virt Bitmap */
2302 	}
2303 }
2304 
2305 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2306 				    struct ps_data *ps, struct sk_buff *skb)
2307 {
2308 	struct ieee80211_local *local = sdata->local;
2309 
2310 	/*
2311 	 * Not very nice, but we want to allow the driver to call
2312 	 * ieee80211_beacon_get() as a response to the set_tim()
2313 	 * callback. That, however, is already invoked under the
2314 	 * sta_lock to guarantee consistent and race-free update
2315 	 * of the tim bitmap in mac80211 and the driver.
2316 	 */
2317 	if (local->tim_in_locked_section) {
2318 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2319 	} else {
2320 		spin_lock_bh(&local->tim_lock);
2321 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2322 		spin_unlock_bh(&local->tim_lock);
2323 	}
2324 
2325 	return 0;
2326 }
2327 
2328 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2329 					 struct ieee80211_vif *vif,
2330 					 u16 *tim_offset, u16 *tim_length)
2331 {
2332 	struct ieee80211_local *local = hw_to_local(hw);
2333 	struct sk_buff *skb = NULL;
2334 	struct ieee80211_tx_info *info;
2335 	struct ieee80211_sub_if_data *sdata = NULL;
2336 	enum ieee80211_band band;
2337 	struct ieee80211_tx_rate_control txrc;
2338 	struct ieee80211_chanctx_conf *chanctx_conf;
2339 
2340 	rcu_read_lock();
2341 
2342 	sdata = vif_to_sdata(vif);
2343 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2344 
2345 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
2346 		goto out;
2347 
2348 	if (tim_offset)
2349 		*tim_offset = 0;
2350 	if (tim_length)
2351 		*tim_length = 0;
2352 
2353 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2354 		struct ieee80211_if_ap *ap = &sdata->u.ap;
2355 		struct beacon_data *beacon = rcu_dereference(ap->beacon);
2356 
2357 		if (beacon) {
2358 			/*
2359 			 * headroom, head length,
2360 			 * tail length and maximum TIM length
2361 			 */
2362 			skb = dev_alloc_skb(local->tx_headroom +
2363 					    beacon->head_len +
2364 					    beacon->tail_len + 256);
2365 			if (!skb)
2366 				goto out;
2367 
2368 			skb_reserve(skb, local->tx_headroom);
2369 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2370 			       beacon->head_len);
2371 
2372 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
2373 
2374 			if (tim_offset)
2375 				*tim_offset = beacon->head_len;
2376 			if (tim_length)
2377 				*tim_length = skb->len - beacon->head_len;
2378 
2379 			if (beacon->tail)
2380 				memcpy(skb_put(skb, beacon->tail_len),
2381 				       beacon->tail, beacon->tail_len);
2382 		} else
2383 			goto out;
2384 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2385 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2386 		struct ieee80211_hdr *hdr;
2387 		struct beacon_data *presp = rcu_dereference(ifibss->presp);
2388 
2389 		if (!presp)
2390 			goto out;
2391 
2392 		skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
2393 		if (!skb)
2394 			goto out;
2395 		skb_reserve(skb, local->tx_headroom);
2396 		memcpy(skb_put(skb, presp->head_len), presp->head,
2397 		       presp->head_len);
2398 
2399 		hdr = (struct ieee80211_hdr *) skb->data;
2400 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2401 						 IEEE80211_STYPE_BEACON);
2402 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2403 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2404 		struct beacon_data *bcn = rcu_dereference(ifmsh->beacon);
2405 
2406 		if (!bcn)
2407 			goto out;
2408 
2409 		if (ifmsh->sync_ops)
2410 			ifmsh->sync_ops->adjust_tbtt(
2411 						sdata);
2412 
2413 		skb = dev_alloc_skb(local->tx_headroom +
2414 				    bcn->head_len +
2415 				    256 + /* TIM IE */
2416 				    bcn->tail_len);
2417 		if (!skb)
2418 			goto out;
2419 		skb_reserve(skb, local->tx_headroom);
2420 		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
2421 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
2422 		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
2423 	} else {
2424 		WARN_ON(1);
2425 		goto out;
2426 	}
2427 
2428 	band = chanctx_conf->def.chan->band;
2429 
2430 	info = IEEE80211_SKB_CB(skb);
2431 
2432 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2433 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2434 	info->band = band;
2435 
2436 	memset(&txrc, 0, sizeof(txrc));
2437 	txrc.hw = hw;
2438 	txrc.sband = local->hw.wiphy->bands[band];
2439 	txrc.bss_conf = &sdata->vif.bss_conf;
2440 	txrc.skb = skb;
2441 	txrc.reported_rate.idx = -1;
2442 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2443 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
2444 		txrc.max_rate_idx = -1;
2445 	else
2446 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2447 	txrc.bss = true;
2448 	rate_control_get_rate(sdata, NULL, &txrc);
2449 
2450 	info->control.vif = vif;
2451 
2452 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2453 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2454 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2455  out:
2456 	rcu_read_unlock();
2457 	return skb;
2458 }
2459 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2460 
2461 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
2462 					struct ieee80211_vif *vif)
2463 {
2464 	struct ieee80211_if_ap *ap = NULL;
2465 	struct sk_buff *skb = NULL;
2466 	struct probe_resp *presp = NULL;
2467 	struct ieee80211_hdr *hdr;
2468 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2469 
2470 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2471 		return NULL;
2472 
2473 	rcu_read_lock();
2474 
2475 	ap = &sdata->u.ap;
2476 	presp = rcu_dereference(ap->probe_resp);
2477 	if (!presp)
2478 		goto out;
2479 
2480 	skb = dev_alloc_skb(presp->len);
2481 	if (!skb)
2482 		goto out;
2483 
2484 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
2485 
2486 	hdr = (struct ieee80211_hdr *) skb->data;
2487 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2488 
2489 out:
2490 	rcu_read_unlock();
2491 	return skb;
2492 }
2493 EXPORT_SYMBOL(ieee80211_proberesp_get);
2494 
2495 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2496 				     struct ieee80211_vif *vif)
2497 {
2498 	struct ieee80211_sub_if_data *sdata;
2499 	struct ieee80211_if_managed *ifmgd;
2500 	struct ieee80211_pspoll *pspoll;
2501 	struct ieee80211_local *local;
2502 	struct sk_buff *skb;
2503 
2504 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2505 		return NULL;
2506 
2507 	sdata = vif_to_sdata(vif);
2508 	ifmgd = &sdata->u.mgd;
2509 	local = sdata->local;
2510 
2511 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2512 	if (!skb)
2513 		return NULL;
2514 
2515 	skb_reserve(skb, local->hw.extra_tx_headroom);
2516 
2517 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2518 	memset(pspoll, 0, sizeof(*pspoll));
2519 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2520 					    IEEE80211_STYPE_PSPOLL);
2521 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2522 
2523 	/* aid in PS-Poll has its two MSBs each set to 1 */
2524 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2525 
2526 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2527 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2528 
2529 	return skb;
2530 }
2531 EXPORT_SYMBOL(ieee80211_pspoll_get);
2532 
2533 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2534 				       struct ieee80211_vif *vif)
2535 {
2536 	struct ieee80211_hdr_3addr *nullfunc;
2537 	struct ieee80211_sub_if_data *sdata;
2538 	struct ieee80211_if_managed *ifmgd;
2539 	struct ieee80211_local *local;
2540 	struct sk_buff *skb;
2541 
2542 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2543 		return NULL;
2544 
2545 	sdata = vif_to_sdata(vif);
2546 	ifmgd = &sdata->u.mgd;
2547 	local = sdata->local;
2548 
2549 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2550 	if (!skb)
2551 		return NULL;
2552 
2553 	skb_reserve(skb, local->hw.extra_tx_headroom);
2554 
2555 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2556 							  sizeof(*nullfunc));
2557 	memset(nullfunc, 0, sizeof(*nullfunc));
2558 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2559 					      IEEE80211_STYPE_NULLFUNC |
2560 					      IEEE80211_FCTL_TODS);
2561 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2562 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2563 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2564 
2565 	return skb;
2566 }
2567 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2568 
2569 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2570 				       struct ieee80211_vif *vif,
2571 				       const u8 *ssid, size_t ssid_len,
2572 				       size_t tailroom)
2573 {
2574 	struct ieee80211_sub_if_data *sdata;
2575 	struct ieee80211_local *local;
2576 	struct ieee80211_hdr_3addr *hdr;
2577 	struct sk_buff *skb;
2578 	size_t ie_ssid_len;
2579 	u8 *pos;
2580 
2581 	sdata = vif_to_sdata(vif);
2582 	local = sdata->local;
2583 	ie_ssid_len = 2 + ssid_len;
2584 
2585 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2586 			    ie_ssid_len + tailroom);
2587 	if (!skb)
2588 		return NULL;
2589 
2590 	skb_reserve(skb, local->hw.extra_tx_headroom);
2591 
2592 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2593 	memset(hdr, 0, sizeof(*hdr));
2594 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2595 					 IEEE80211_STYPE_PROBE_REQ);
2596 	eth_broadcast_addr(hdr->addr1);
2597 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2598 	eth_broadcast_addr(hdr->addr3);
2599 
2600 	pos = skb_put(skb, ie_ssid_len);
2601 	*pos++ = WLAN_EID_SSID;
2602 	*pos++ = ssid_len;
2603 	if (ssid_len)
2604 		memcpy(pos, ssid, ssid_len);
2605 	pos += ssid_len;
2606 
2607 	return skb;
2608 }
2609 EXPORT_SYMBOL(ieee80211_probereq_get);
2610 
2611 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2612 		       const void *frame, size_t frame_len,
2613 		       const struct ieee80211_tx_info *frame_txctl,
2614 		       struct ieee80211_rts *rts)
2615 {
2616 	const struct ieee80211_hdr *hdr = frame;
2617 
2618 	rts->frame_control =
2619 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2620 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2621 					       frame_txctl);
2622 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2623 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2624 }
2625 EXPORT_SYMBOL(ieee80211_rts_get);
2626 
2627 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2628 			     const void *frame, size_t frame_len,
2629 			     const struct ieee80211_tx_info *frame_txctl,
2630 			     struct ieee80211_cts *cts)
2631 {
2632 	const struct ieee80211_hdr *hdr = frame;
2633 
2634 	cts->frame_control =
2635 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2636 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2637 						     frame_len, frame_txctl);
2638 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2639 }
2640 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2641 
2642 struct sk_buff *
2643 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2644 			  struct ieee80211_vif *vif)
2645 {
2646 	struct ieee80211_local *local = hw_to_local(hw);
2647 	struct sk_buff *skb = NULL;
2648 	struct ieee80211_tx_data tx;
2649 	struct ieee80211_sub_if_data *sdata;
2650 	struct ps_data *ps;
2651 	struct ieee80211_tx_info *info;
2652 	struct ieee80211_chanctx_conf *chanctx_conf;
2653 
2654 	sdata = vif_to_sdata(vif);
2655 
2656 	rcu_read_lock();
2657 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2658 
2659 	if (!chanctx_conf)
2660 		goto out;
2661 
2662 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2663 		struct beacon_data *beacon =
2664 				rcu_dereference(sdata->u.ap.beacon);
2665 
2666 		if (!beacon || !beacon->head)
2667 			goto out;
2668 
2669 		ps = &sdata->u.ap.ps;
2670 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2671 		ps = &sdata->u.mesh.ps;
2672 	} else {
2673 		goto out;
2674 	}
2675 
2676 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
2677 		goto out; /* send buffered bc/mc only after DTIM beacon */
2678 
2679 	while (1) {
2680 		skb = skb_dequeue(&ps->bc_buf);
2681 		if (!skb)
2682 			goto out;
2683 		local->total_ps_buffered--;
2684 
2685 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
2686 			struct ieee80211_hdr *hdr =
2687 				(struct ieee80211_hdr *) skb->data;
2688 			/* more buffered multicast/broadcast frames ==> set
2689 			 * MoreData flag in IEEE 802.11 header to inform PS
2690 			 * STAs */
2691 			hdr->frame_control |=
2692 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2693 		}
2694 
2695 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2696 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
2697 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2698 			break;
2699 		dev_kfree_skb_any(skb);
2700 	}
2701 
2702 	info = IEEE80211_SKB_CB(skb);
2703 
2704 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2705 	info->band = chanctx_conf->def.chan->band;
2706 
2707 	if (invoke_tx_handlers(&tx))
2708 		skb = NULL;
2709  out:
2710 	rcu_read_unlock();
2711 
2712 	return skb;
2713 }
2714 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2715 
2716 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
2717 				 struct sk_buff *skb, int tid,
2718 				 enum ieee80211_band band)
2719 {
2720 	int ac = ieee802_1d_to_ac[tid & 7];
2721 
2722 	skb_set_mac_header(skb, 0);
2723 	skb_set_network_header(skb, 0);
2724 	skb_set_transport_header(skb, 0);
2725 
2726 	skb_set_queue_mapping(skb, ac);
2727 	skb->priority = tid;
2728 
2729 	skb->dev = sdata->dev;
2730 
2731 	/*
2732 	 * The other path calling ieee80211_xmit is from the tasklet,
2733 	 * and while we can handle concurrent transmissions locking
2734 	 * requirements are that we do not come into tx with bhs on.
2735 	 */
2736 	local_bh_disable();
2737 	ieee80211_xmit(sdata, skb, band);
2738 	local_bh_enable();
2739 }
2740