xref: /openbmc/linux/net/mac80211/tx.c (revision ee8a99bd)
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 	if (tx->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
402 		info->hw_queue = tx->sdata->vif.cab_queue;
403 
404 	/* no stations in PS mode */
405 	if (!atomic_read(&ps->num_sta_ps))
406 		return TX_CONTINUE;
407 
408 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
409 
410 	/* device releases frame after DTIM beacon */
411 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
412 		return TX_CONTINUE;
413 
414 	/* buffered in mac80211 */
415 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
416 		purge_old_ps_buffers(tx->local);
417 
418 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
419 		ps_dbg(tx->sdata,
420 		       "BC TX buffer full - dropping the oldest frame\n");
421 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
422 	} else
423 		tx->local->total_ps_buffered++;
424 
425 	skb_queue_tail(&ps->bc_buf, tx->skb);
426 
427 	return TX_QUEUED;
428 }
429 
430 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
431 			     struct sk_buff *skb)
432 {
433 	if (!ieee80211_is_mgmt(fc))
434 		return 0;
435 
436 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
437 		return 0;
438 
439 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
440 					    skb->data))
441 		return 0;
442 
443 	return 1;
444 }
445 
446 static ieee80211_tx_result
447 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
448 {
449 	struct sta_info *sta = tx->sta;
450 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
451 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
452 	struct ieee80211_local *local = tx->local;
453 
454 	if (unlikely(!sta))
455 		return TX_CONTINUE;
456 
457 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
458 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
459 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
460 		int ac = skb_get_queue_mapping(tx->skb);
461 
462 		/* only deauth, disassoc and action are bufferable MMPDUs */
463 		if (ieee80211_is_mgmt(hdr->frame_control) &&
464 		    !ieee80211_is_deauth(hdr->frame_control) &&
465 		    !ieee80211_is_disassoc(hdr->frame_control) &&
466 		    !ieee80211_is_action(hdr->frame_control)) {
467 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
468 			return TX_CONTINUE;
469 		}
470 
471 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
472 		       sta->sta.addr, sta->sta.aid, ac);
473 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
474 			purge_old_ps_buffers(tx->local);
475 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
476 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
477 			ps_dbg(tx->sdata,
478 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
479 			       sta->sta.addr, ac);
480 			ieee80211_free_txskb(&local->hw, old);
481 		} else
482 			tx->local->total_ps_buffered++;
483 
484 		info->control.jiffies = jiffies;
485 		info->control.vif = &tx->sdata->vif;
486 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
487 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
488 
489 		if (!timer_pending(&local->sta_cleanup))
490 			mod_timer(&local->sta_cleanup,
491 				  round_jiffies(jiffies +
492 						STA_INFO_CLEANUP_INTERVAL));
493 
494 		/*
495 		 * We queued up some frames, so the TIM bit might
496 		 * need to be set, recalculate it.
497 		 */
498 		sta_info_recalc_tim(sta);
499 
500 		return TX_QUEUED;
501 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
502 		ps_dbg(tx->sdata,
503 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
504 		       sta->sta.addr);
505 	}
506 
507 	return TX_CONTINUE;
508 }
509 
510 static ieee80211_tx_result debug_noinline
511 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
512 {
513 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
514 		return TX_CONTINUE;
515 
516 	if (tx->flags & IEEE80211_TX_UNICAST)
517 		return ieee80211_tx_h_unicast_ps_buf(tx);
518 	else
519 		return ieee80211_tx_h_multicast_ps_buf(tx);
520 }
521 
522 static ieee80211_tx_result debug_noinline
523 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
524 {
525 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
526 
527 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
528 		     tx->sdata->control_port_no_encrypt))
529 		info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
530 
531 	return TX_CONTINUE;
532 }
533 
534 static ieee80211_tx_result debug_noinline
535 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
536 {
537 	struct ieee80211_key *key;
538 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
539 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
540 
541 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
542 		tx->key = NULL;
543 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
544 		tx->key = key;
545 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
546 		 is_multicast_ether_addr(hdr->addr1) &&
547 		 ieee80211_is_robust_mgmt_frame(hdr) &&
548 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
549 		tx->key = key;
550 	else if (is_multicast_ether_addr(hdr->addr1) &&
551 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
552 		tx->key = key;
553 	else if (!is_multicast_ether_addr(hdr->addr1) &&
554 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
555 		tx->key = key;
556 	else if (info->flags & IEEE80211_TX_CTL_INJECTED)
557 		tx->key = NULL;
558 	else if (!tx->sdata->drop_unencrypted)
559 		tx->key = NULL;
560 	else if (tx->skb->protocol == tx->sdata->control_port_protocol)
561 		tx->key = NULL;
562 	else if (ieee80211_is_robust_mgmt_frame(hdr) &&
563 		 !(ieee80211_is_action(hdr->frame_control) &&
564 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))
565 		tx->key = NULL;
566 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
567 		 !ieee80211_is_robust_mgmt_frame(hdr))
568 		tx->key = NULL;
569 	else {
570 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
571 		return TX_DROP;
572 	}
573 
574 	if (tx->key) {
575 		bool skip_hw = false;
576 
577 		tx->key->tx_rx_count++;
578 		/* TODO: add threshold stuff again */
579 
580 		switch (tx->key->conf.cipher) {
581 		case WLAN_CIPHER_SUITE_WEP40:
582 		case WLAN_CIPHER_SUITE_WEP104:
583 		case WLAN_CIPHER_SUITE_TKIP:
584 			if (!ieee80211_is_data_present(hdr->frame_control))
585 				tx->key = NULL;
586 			break;
587 		case WLAN_CIPHER_SUITE_CCMP:
588 			if (!ieee80211_is_data_present(hdr->frame_control) &&
589 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
590 					       tx->skb))
591 				tx->key = NULL;
592 			else
593 				skip_hw = (tx->key->conf.flags &
594 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
595 					ieee80211_is_mgmt(hdr->frame_control);
596 			break;
597 		case WLAN_CIPHER_SUITE_AES_CMAC:
598 			if (!ieee80211_is_mgmt(hdr->frame_control))
599 				tx->key = NULL;
600 			break;
601 		}
602 
603 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
604 			     !ieee80211_is_deauth(hdr->frame_control)))
605 			return TX_DROP;
606 
607 		if (!skip_hw && tx->key &&
608 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
609 			info->control.hw_key = &tx->key->conf;
610 	}
611 
612 	return TX_CONTINUE;
613 }
614 
615 static ieee80211_tx_result debug_noinline
616 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
617 {
618 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
619 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
620 	struct ieee80211_supported_band *sband;
621 	u32 len;
622 	struct ieee80211_tx_rate_control txrc;
623 	struct ieee80211_sta_rates *ratetbl = NULL;
624 	bool assoc = false;
625 
626 	memset(&txrc, 0, sizeof(txrc));
627 
628 	sband = tx->local->hw.wiphy->bands[info->band];
629 
630 	len = min_t(u32, tx->skb->len + FCS_LEN,
631 			 tx->local->hw.wiphy->frag_threshold);
632 
633 	/* set up the tx rate control struct we give the RC algo */
634 	txrc.hw = &tx->local->hw;
635 	txrc.sband = sband;
636 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
637 	txrc.skb = tx->skb;
638 	txrc.reported_rate.idx = -1;
639 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
640 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
641 		txrc.max_rate_idx = -1;
642 	else
643 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
644 
645 	if (tx->sdata->rc_has_mcs_mask[info->band])
646 		txrc.rate_idx_mcs_mask =
647 			tx->sdata->rc_rateidx_mcs_mask[info->band];
648 
649 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
650 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
651 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
652 
653 	/* set up RTS protection if desired */
654 	if (len > tx->local->hw.wiphy->rts_threshold) {
655 		txrc.rts = true;
656 	}
657 
658 	info->control.use_rts = txrc.rts;
659 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
660 
661 	/*
662 	 * Use short preamble if the BSS can handle it, but not for
663 	 * management frames unless we know the receiver can handle
664 	 * that -- the management frame might be to a station that
665 	 * just wants a probe response.
666 	 */
667 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
668 	    (ieee80211_is_data(hdr->frame_control) ||
669 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
670 		txrc.short_preamble = true;
671 
672 	info->control.short_preamble = txrc.short_preamble;
673 
674 	if (tx->sta)
675 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
676 
677 	/*
678 	 * Lets not bother rate control if we're associated and cannot
679 	 * talk to the sta. This should not happen.
680 	 */
681 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
682 		 !rate_usable_index_exists(sband, &tx->sta->sta),
683 		 "%s: Dropped data frame as no usable bitrate found while "
684 		 "scanning and associated. Target station: "
685 		 "%pM on %d GHz band\n",
686 		 tx->sdata->name, hdr->addr1,
687 		 info->band ? 5 : 2))
688 		return TX_DROP;
689 
690 	/*
691 	 * If we're associated with the sta at this point we know we can at
692 	 * least send the frame at the lowest bit rate.
693 	 */
694 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
695 
696 	if (tx->sta && !info->control.skip_table)
697 		ratetbl = rcu_dereference(tx->sta->sta.rates);
698 
699 	if (unlikely(info->control.rates[0].idx < 0)) {
700 		if (ratetbl) {
701 			struct ieee80211_tx_rate rate = {
702 				.idx = ratetbl->rate[0].idx,
703 				.flags = ratetbl->rate[0].flags,
704 				.count = ratetbl->rate[0].count
705 			};
706 
707 			if (ratetbl->rate[0].idx < 0)
708 				return TX_DROP;
709 
710 			tx->rate = rate;
711 		} else {
712 			return TX_DROP;
713 		}
714 	} else {
715 		tx->rate = info->control.rates[0];
716 	}
717 
718 	if (txrc.reported_rate.idx < 0) {
719 		txrc.reported_rate = tx->rate;
720 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
721 			tx->sta->last_tx_rate = txrc.reported_rate;
722 	} else if (tx->sta)
723 		tx->sta->last_tx_rate = txrc.reported_rate;
724 
725 	if (ratetbl)
726 		return TX_CONTINUE;
727 
728 	if (unlikely(!info->control.rates[0].count))
729 		info->control.rates[0].count = 1;
730 
731 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
732 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
733 		info->control.rates[0].count = 1;
734 
735 	return TX_CONTINUE;
736 }
737 
738 static ieee80211_tx_result debug_noinline
739 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
740 {
741 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
742 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
743 	u16 *seq;
744 	u8 *qc;
745 	int tid;
746 
747 	/*
748 	 * Packet injection may want to control the sequence
749 	 * number, if we have no matching interface then we
750 	 * neither assign one ourselves nor ask the driver to.
751 	 */
752 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
753 		return TX_CONTINUE;
754 
755 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
756 		return TX_CONTINUE;
757 
758 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
759 		return TX_CONTINUE;
760 
761 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
762 		return TX_CONTINUE;
763 
764 	/*
765 	 * Anything but QoS data that has a sequence number field
766 	 * (is long enough) gets a sequence number from the global
767 	 * counter.
768 	 */
769 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
770 		/* driver should assign sequence number */
771 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
772 		/* for pure STA mode without beacons, we can do it */
773 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
774 		tx->sdata->sequence_number += 0x10;
775 		return TX_CONTINUE;
776 	}
777 
778 	/*
779 	 * This should be true for injected/management frames only, for
780 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
781 	 * above since they are not QoS-data frames.
782 	 */
783 	if (!tx->sta)
784 		return TX_CONTINUE;
785 
786 	/* include per-STA, per-TID sequence counter */
787 
788 	qc = ieee80211_get_qos_ctl(hdr);
789 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
790 	seq = &tx->sta->tid_seq[tid];
791 
792 	hdr->seq_ctrl = cpu_to_le16(*seq);
793 
794 	/* Increase the sequence number. */
795 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
796 
797 	return TX_CONTINUE;
798 }
799 
800 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
801 			      struct sk_buff *skb, int hdrlen,
802 			      int frag_threshold)
803 {
804 	struct ieee80211_local *local = tx->local;
805 	struct ieee80211_tx_info *info;
806 	struct sk_buff *tmp;
807 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
808 	int pos = hdrlen + per_fragm;
809 	int rem = skb->len - hdrlen - per_fragm;
810 
811 	if (WARN_ON(rem < 0))
812 		return -EINVAL;
813 
814 	/* first fragment was already added to queue by caller */
815 
816 	while (rem) {
817 		int fraglen = per_fragm;
818 
819 		if (fraglen > rem)
820 			fraglen = rem;
821 		rem -= fraglen;
822 		tmp = dev_alloc_skb(local->tx_headroom +
823 				    frag_threshold +
824 				    IEEE80211_ENCRYPT_HEADROOM +
825 				    IEEE80211_ENCRYPT_TAILROOM);
826 		if (!tmp)
827 			return -ENOMEM;
828 
829 		__skb_queue_tail(&tx->skbs, tmp);
830 
831 		skb_reserve(tmp, local->tx_headroom +
832 				 IEEE80211_ENCRYPT_HEADROOM);
833 		/* copy control information */
834 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
835 
836 		info = IEEE80211_SKB_CB(tmp);
837 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
838 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
839 
840 		if (rem)
841 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
842 
843 		skb_copy_queue_mapping(tmp, skb);
844 		tmp->priority = skb->priority;
845 		tmp->dev = skb->dev;
846 
847 		/* copy header and data */
848 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
849 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
850 
851 		pos += fraglen;
852 	}
853 
854 	/* adjust first fragment's length */
855 	skb->len = hdrlen + per_fragm;
856 	return 0;
857 }
858 
859 static ieee80211_tx_result debug_noinline
860 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
861 {
862 	struct sk_buff *skb = tx->skb;
863 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
864 	struct ieee80211_hdr *hdr = (void *)skb->data;
865 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
866 	int hdrlen;
867 	int fragnum;
868 
869 	/* no matter what happens, tx->skb moves to tx->skbs */
870 	__skb_queue_tail(&tx->skbs, skb);
871 	tx->skb = NULL;
872 
873 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
874 		return TX_CONTINUE;
875 
876 	if (tx->local->ops->set_frag_threshold)
877 		return TX_CONTINUE;
878 
879 	/*
880 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
881 	 * This scenario is handled in ieee80211_tx_prepare but extra
882 	 * caution taken here as fragmented ampdu may cause Tx stop.
883 	 */
884 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
885 		return TX_DROP;
886 
887 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
888 
889 	/* internal error, why isn't DONTFRAG set? */
890 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
891 		return TX_DROP;
892 
893 	/*
894 	 * Now fragment the frame. This will allocate all the fragments and
895 	 * chain them (using skb as the first fragment) to skb->next.
896 	 * During transmission, we will remove the successfully transmitted
897 	 * fragments from this list. When the low-level driver rejects one
898 	 * of the fragments then we will simply pretend to accept the skb
899 	 * but store it away as pending.
900 	 */
901 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
902 		return TX_DROP;
903 
904 	/* update duration/seq/flags of fragments */
905 	fragnum = 0;
906 
907 	skb_queue_walk(&tx->skbs, skb) {
908 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
909 
910 		hdr = (void *)skb->data;
911 		info = IEEE80211_SKB_CB(skb);
912 
913 		if (!skb_queue_is_last(&tx->skbs, skb)) {
914 			hdr->frame_control |= morefrags;
915 			/*
916 			 * No multi-rate retries for fragmented frames, that
917 			 * would completely throw off the NAV at other STAs.
918 			 */
919 			info->control.rates[1].idx = -1;
920 			info->control.rates[2].idx = -1;
921 			info->control.rates[3].idx = -1;
922 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
923 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
924 		} else {
925 			hdr->frame_control &= ~morefrags;
926 		}
927 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
928 		fragnum++;
929 	}
930 
931 	return TX_CONTINUE;
932 }
933 
934 static ieee80211_tx_result debug_noinline
935 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
936 {
937 	struct sk_buff *skb;
938 	int ac = -1;
939 
940 	if (!tx->sta)
941 		return TX_CONTINUE;
942 
943 	skb_queue_walk(&tx->skbs, skb) {
944 		ac = skb_get_queue_mapping(skb);
945 		tx->sta->tx_fragments++;
946 		tx->sta->tx_bytes[ac] += skb->len;
947 	}
948 	if (ac >= 0)
949 		tx->sta->tx_packets[ac]++;
950 
951 	return TX_CONTINUE;
952 }
953 
954 static ieee80211_tx_result debug_noinline
955 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
956 {
957 	if (!tx->key)
958 		return TX_CONTINUE;
959 
960 	switch (tx->key->conf.cipher) {
961 	case WLAN_CIPHER_SUITE_WEP40:
962 	case WLAN_CIPHER_SUITE_WEP104:
963 		return ieee80211_crypto_wep_encrypt(tx);
964 	case WLAN_CIPHER_SUITE_TKIP:
965 		return ieee80211_crypto_tkip_encrypt(tx);
966 	case WLAN_CIPHER_SUITE_CCMP:
967 		return ieee80211_crypto_ccmp_encrypt(tx);
968 	case WLAN_CIPHER_SUITE_AES_CMAC:
969 		return ieee80211_crypto_aes_cmac_encrypt(tx);
970 	default:
971 		return ieee80211_crypto_hw_encrypt(tx);
972 	}
973 
974 	return TX_DROP;
975 }
976 
977 static ieee80211_tx_result debug_noinline
978 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
979 {
980 	struct sk_buff *skb;
981 	struct ieee80211_hdr *hdr;
982 	int next_len;
983 	bool group_addr;
984 
985 	skb_queue_walk(&tx->skbs, skb) {
986 		hdr = (void *) skb->data;
987 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
988 			break; /* must not overwrite AID */
989 		if (!skb_queue_is_last(&tx->skbs, skb)) {
990 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
991 			next_len = next->len;
992 		} else
993 			next_len = 0;
994 		group_addr = is_multicast_ether_addr(hdr->addr1);
995 
996 		hdr->duration_id =
997 			ieee80211_duration(tx, skb, group_addr, next_len);
998 	}
999 
1000 	return TX_CONTINUE;
1001 }
1002 
1003 /* actual transmit path */
1004 
1005 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1006 				  struct sk_buff *skb,
1007 				  struct ieee80211_tx_info *info,
1008 				  struct tid_ampdu_tx *tid_tx,
1009 				  int tid)
1010 {
1011 	bool queued = false;
1012 	bool reset_agg_timer = false;
1013 	struct sk_buff *purge_skb = NULL;
1014 
1015 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1016 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1017 		reset_agg_timer = true;
1018 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1019 		/*
1020 		 * nothing -- this aggregation session is being started
1021 		 * but that might still fail with the driver
1022 		 */
1023 	} else {
1024 		spin_lock(&tx->sta->lock);
1025 		/*
1026 		 * Need to re-check now, because we may get here
1027 		 *
1028 		 *  1) in the window during which the setup is actually
1029 		 *     already done, but not marked yet because not all
1030 		 *     packets are spliced over to the driver pending
1031 		 *     queue yet -- if this happened we acquire the lock
1032 		 *     either before or after the splice happens, but
1033 		 *     need to recheck which of these cases happened.
1034 		 *
1035 		 *  2) during session teardown, if the OPERATIONAL bit
1036 		 *     was cleared due to the teardown but the pointer
1037 		 *     hasn't been assigned NULL yet (or we loaded it
1038 		 *     before it was assigned) -- in this case it may
1039 		 *     now be NULL which means we should just let the
1040 		 *     packet pass through because splicing the frames
1041 		 *     back is already done.
1042 		 */
1043 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1044 
1045 		if (!tid_tx) {
1046 			/* do nothing, let packet pass through */
1047 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1048 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1049 			reset_agg_timer = true;
1050 		} else {
1051 			queued = true;
1052 			info->control.vif = &tx->sdata->vif;
1053 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1054 			__skb_queue_tail(&tid_tx->pending, skb);
1055 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1056 				purge_skb = __skb_dequeue(&tid_tx->pending);
1057 		}
1058 		spin_unlock(&tx->sta->lock);
1059 
1060 		if (purge_skb)
1061 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1062 	}
1063 
1064 	/* reset session timer */
1065 	if (reset_agg_timer && tid_tx->timeout)
1066 		tid_tx->last_tx = jiffies;
1067 
1068 	return queued;
1069 }
1070 
1071 /*
1072  * initialises @tx
1073  */
1074 static ieee80211_tx_result
1075 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1076 		     struct ieee80211_tx_data *tx,
1077 		     struct sk_buff *skb)
1078 {
1079 	struct ieee80211_local *local = sdata->local;
1080 	struct ieee80211_hdr *hdr;
1081 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1082 	int tid;
1083 	u8 *qc;
1084 
1085 	memset(tx, 0, sizeof(*tx));
1086 	tx->skb = skb;
1087 	tx->local = local;
1088 	tx->sdata = sdata;
1089 	__skb_queue_head_init(&tx->skbs);
1090 
1091 	/*
1092 	 * If this flag is set to true anywhere, and we get here,
1093 	 * we are doing the needed processing, so remove the flag
1094 	 * now.
1095 	 */
1096 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1097 
1098 	hdr = (struct ieee80211_hdr *) skb->data;
1099 
1100 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1101 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1102 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1103 			return TX_DROP;
1104 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED ||
1105 		   tx->sdata->control_port_protocol == tx->skb->protocol) {
1106 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1107 	}
1108 	if (!tx->sta)
1109 		tx->sta = sta_info_get(sdata, hdr->addr1);
1110 
1111 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1112 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1113 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1114 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1115 		struct tid_ampdu_tx *tid_tx;
1116 
1117 		qc = ieee80211_get_qos_ctl(hdr);
1118 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1119 
1120 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1121 		if (tid_tx) {
1122 			bool queued;
1123 
1124 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1125 						       tid_tx, tid);
1126 
1127 			if (unlikely(queued))
1128 				return TX_QUEUED;
1129 		}
1130 	}
1131 
1132 	if (is_multicast_ether_addr(hdr->addr1)) {
1133 		tx->flags &= ~IEEE80211_TX_UNICAST;
1134 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1135 	} else
1136 		tx->flags |= IEEE80211_TX_UNICAST;
1137 
1138 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1139 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1140 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1141 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1142 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1143 	}
1144 
1145 	if (!tx->sta)
1146 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1147 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1148 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1149 
1150 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1151 
1152 	return TX_CONTINUE;
1153 }
1154 
1155 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1156 			       struct ieee80211_vif *vif,
1157 			       struct ieee80211_sta *sta,
1158 			       struct sk_buff_head *skbs,
1159 			       bool txpending)
1160 {
1161 	struct ieee80211_tx_control control;
1162 	struct sk_buff *skb, *tmp;
1163 	unsigned long flags;
1164 
1165 	skb_queue_walk_safe(skbs, skb, tmp) {
1166 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1167 		int q = info->hw_queue;
1168 
1169 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1170 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1171 			__skb_unlink(skb, skbs);
1172 			ieee80211_free_txskb(&local->hw, skb);
1173 			continue;
1174 		}
1175 #endif
1176 
1177 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1178 		if (local->queue_stop_reasons[q] ||
1179 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1180 			if (unlikely(info->flags &
1181 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1182 				if (local->queue_stop_reasons[q] &
1183 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1184 					/*
1185 					 * Drop off-channel frames if queues
1186 					 * are stopped for any reason other
1187 					 * than off-channel operation. Never
1188 					 * queue them.
1189 					 */
1190 					spin_unlock_irqrestore(
1191 						&local->queue_stop_reason_lock,
1192 						flags);
1193 					ieee80211_purge_tx_queue(&local->hw,
1194 								 skbs);
1195 					return true;
1196 				}
1197 			} else {
1198 
1199 				/*
1200 				 * Since queue is stopped, queue up frames for
1201 				 * later transmission from the tx-pending
1202 				 * tasklet when the queue is woken again.
1203 				 */
1204 				if (txpending)
1205 					skb_queue_splice_init(skbs,
1206 							      &local->pending[q]);
1207 				else
1208 					skb_queue_splice_tail_init(skbs,
1209 								   &local->pending[q]);
1210 
1211 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1212 						       flags);
1213 				return false;
1214 			}
1215 		}
1216 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1217 
1218 		info->control.vif = vif;
1219 		control.sta = sta;
1220 
1221 		__skb_unlink(skb, skbs);
1222 		drv_tx(local, &control, skb);
1223 	}
1224 
1225 	return true;
1226 }
1227 
1228 /*
1229  * Returns false if the frame couldn't be transmitted but was queued instead.
1230  */
1231 static bool __ieee80211_tx(struct ieee80211_local *local,
1232 			   struct sk_buff_head *skbs, int led_len,
1233 			   struct sta_info *sta, bool txpending)
1234 {
1235 	struct ieee80211_tx_info *info;
1236 	struct ieee80211_sub_if_data *sdata;
1237 	struct ieee80211_vif *vif;
1238 	struct ieee80211_sta *pubsta;
1239 	struct sk_buff *skb;
1240 	bool result = true;
1241 	__le16 fc;
1242 
1243 	if (WARN_ON(skb_queue_empty(skbs)))
1244 		return true;
1245 
1246 	skb = skb_peek(skbs);
1247 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1248 	info = IEEE80211_SKB_CB(skb);
1249 	sdata = vif_to_sdata(info->control.vif);
1250 	if (sta && !sta->uploaded)
1251 		sta = NULL;
1252 
1253 	if (sta)
1254 		pubsta = &sta->sta;
1255 	else
1256 		pubsta = NULL;
1257 
1258 	switch (sdata->vif.type) {
1259 	case NL80211_IFTYPE_MONITOR:
1260 		sdata = rcu_dereference(local->monitor_sdata);
1261 		if (sdata) {
1262 			vif = &sdata->vif;
1263 			info->hw_queue =
1264 				vif->hw_queue[skb_get_queue_mapping(skb)];
1265 		} else if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL) {
1266 			dev_kfree_skb(skb);
1267 			return true;
1268 		} else
1269 			vif = NULL;
1270 		break;
1271 	case NL80211_IFTYPE_AP_VLAN:
1272 		sdata = container_of(sdata->bss,
1273 				     struct ieee80211_sub_if_data, u.ap);
1274 		/* fall through */
1275 	default:
1276 		vif = &sdata->vif;
1277 		break;
1278 	}
1279 
1280 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1281 				    txpending);
1282 
1283 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1284 	ieee80211_led_tx(local, 1);
1285 
1286 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1287 
1288 	return result;
1289 }
1290 
1291 /*
1292  * Invoke TX handlers, return 0 on success and non-zero if the
1293  * frame was dropped or queued.
1294  */
1295 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1296 {
1297 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1298 	ieee80211_tx_result res = TX_DROP;
1299 
1300 #define CALL_TXH(txh) \
1301 	do {				\
1302 		res = txh(tx);		\
1303 		if (res != TX_CONTINUE)	\
1304 			goto txh_done;	\
1305 	} while (0)
1306 
1307 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1308 	CALL_TXH(ieee80211_tx_h_check_assoc);
1309 	CALL_TXH(ieee80211_tx_h_ps_buf);
1310 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1311 	CALL_TXH(ieee80211_tx_h_select_key);
1312 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1313 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1314 
1315 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1316 		__skb_queue_tail(&tx->skbs, tx->skb);
1317 		tx->skb = NULL;
1318 		goto txh_done;
1319 	}
1320 
1321 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1322 	CALL_TXH(ieee80211_tx_h_sequence);
1323 	CALL_TXH(ieee80211_tx_h_fragment);
1324 	/* handlers after fragment must be aware of tx info fragmentation! */
1325 	CALL_TXH(ieee80211_tx_h_stats);
1326 	CALL_TXH(ieee80211_tx_h_encrypt);
1327 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1328 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1329 #undef CALL_TXH
1330 
1331  txh_done:
1332 	if (unlikely(res == TX_DROP)) {
1333 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1334 		if (tx->skb)
1335 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1336 		else
1337 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1338 		return -1;
1339 	} else if (unlikely(res == TX_QUEUED)) {
1340 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1341 		return -1;
1342 	}
1343 
1344 	return 0;
1345 }
1346 
1347 /*
1348  * Returns false if the frame couldn't be transmitted but was queued instead.
1349  */
1350 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1351 			 struct sk_buff *skb, bool txpending,
1352 			 enum ieee80211_band band)
1353 {
1354 	struct ieee80211_local *local = sdata->local;
1355 	struct ieee80211_tx_data tx;
1356 	ieee80211_tx_result res_prepare;
1357 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1358 	bool result = true;
1359 	int led_len;
1360 
1361 	if (unlikely(skb->len < 10)) {
1362 		dev_kfree_skb(skb);
1363 		return true;
1364 	}
1365 
1366 	/* initialises tx */
1367 	led_len = skb->len;
1368 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1369 
1370 	if (unlikely(res_prepare == TX_DROP)) {
1371 		ieee80211_free_txskb(&local->hw, skb);
1372 		return true;
1373 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1374 		return true;
1375 	}
1376 
1377 	info->band = band;
1378 
1379 	/* set up hw_queue value early */
1380 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1381 	    !(local->hw.flags & IEEE80211_HW_QUEUE_CONTROL))
1382 		info->hw_queue =
1383 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1384 
1385 	if (!invoke_tx_handlers(&tx))
1386 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1387 					tx.sta, txpending);
1388 
1389 	return result;
1390 }
1391 
1392 /* device xmit handlers */
1393 
1394 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1395 				struct sk_buff *skb,
1396 				int head_need, bool may_encrypt)
1397 {
1398 	struct ieee80211_local *local = sdata->local;
1399 	int tail_need = 0;
1400 
1401 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1402 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1403 		tail_need -= skb_tailroom(skb);
1404 		tail_need = max_t(int, tail_need, 0);
1405 	}
1406 
1407 	if (skb_cloned(skb))
1408 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1409 	else if (head_need || tail_need)
1410 		I802_DEBUG_INC(local->tx_expand_skb_head);
1411 	else
1412 		return 0;
1413 
1414 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1415 		wiphy_debug(local->hw.wiphy,
1416 			    "failed to reallocate TX buffer\n");
1417 		return -ENOMEM;
1418 	}
1419 
1420 	return 0;
1421 }
1422 
1423 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
1424 		    enum ieee80211_band band)
1425 {
1426 	struct ieee80211_local *local = sdata->local;
1427 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1428 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1429 	int headroom;
1430 	bool may_encrypt;
1431 
1432 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1433 
1434 	headroom = local->tx_headroom;
1435 	if (may_encrypt)
1436 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1437 	headroom -= skb_headroom(skb);
1438 	headroom = max_t(int, 0, headroom);
1439 
1440 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1441 		ieee80211_free_txskb(&local->hw, skb);
1442 		return;
1443 	}
1444 
1445 	hdr = (struct ieee80211_hdr *) skb->data;
1446 	info->control.vif = &sdata->vif;
1447 
1448 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1449 		if (ieee80211_is_data(hdr->frame_control) &&
1450 		    is_unicast_ether_addr(hdr->addr1)) {
1451 			if (mesh_nexthop_resolve(sdata, skb))
1452 				return; /* skb queued: don't free */
1453 		} else {
1454 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1455 		}
1456 	}
1457 
1458 	ieee80211_set_qos_hdr(sdata, skb);
1459 	ieee80211_tx(sdata, skb, false, band);
1460 }
1461 
1462 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1463 {
1464 	struct ieee80211_radiotap_iterator iterator;
1465 	struct ieee80211_radiotap_header *rthdr =
1466 		(struct ieee80211_radiotap_header *) skb->data;
1467 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1468 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1469 						   NULL);
1470 	u16 txflags;
1471 
1472 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1473 		       IEEE80211_TX_CTL_DONTFRAG;
1474 
1475 	/*
1476 	 * for every radiotap entry that is present
1477 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1478 	 * entries present, or -EINVAL on error)
1479 	 */
1480 
1481 	while (!ret) {
1482 		ret = ieee80211_radiotap_iterator_next(&iterator);
1483 
1484 		if (ret)
1485 			continue;
1486 
1487 		/* see if this argument is something we can use */
1488 		switch (iterator.this_arg_index) {
1489 		/*
1490 		 * You must take care when dereferencing iterator.this_arg
1491 		 * for multibyte types... the pointer is not aligned.  Use
1492 		 * get_unaligned((type *)iterator.this_arg) to dereference
1493 		 * iterator.this_arg for type "type" safely on all arches.
1494 		*/
1495 		case IEEE80211_RADIOTAP_FLAGS:
1496 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1497 				/*
1498 				 * this indicates that the skb we have been
1499 				 * handed has the 32-bit FCS CRC at the end...
1500 				 * we should react to that by snipping it off
1501 				 * because it will be recomputed and added
1502 				 * on transmission
1503 				 */
1504 				if (skb->len < (iterator._max_length + FCS_LEN))
1505 					return false;
1506 
1507 				skb_trim(skb, skb->len - FCS_LEN);
1508 			}
1509 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1510 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1511 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1512 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1513 			break;
1514 
1515 		case IEEE80211_RADIOTAP_TX_FLAGS:
1516 			txflags = get_unaligned_le16(iterator.this_arg);
1517 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1518 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1519 			break;
1520 
1521 		/*
1522 		 * Please update the file
1523 		 * Documentation/networking/mac80211-injection.txt
1524 		 * when parsing new fields here.
1525 		 */
1526 
1527 		default:
1528 			break;
1529 		}
1530 	}
1531 
1532 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1533 		return false;
1534 
1535 	/*
1536 	 * remove the radiotap header
1537 	 * iterator->_max_length was sanity-checked against
1538 	 * skb->len by iterator init
1539 	 */
1540 	skb_pull(skb, iterator._max_length);
1541 
1542 	return true;
1543 }
1544 
1545 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1546 					 struct net_device *dev)
1547 {
1548 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1549 	struct ieee80211_chanctx_conf *chanctx_conf;
1550 	struct ieee80211_channel *chan;
1551 	struct ieee80211_radiotap_header *prthdr =
1552 		(struct ieee80211_radiotap_header *)skb->data;
1553 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1554 	struct ieee80211_hdr *hdr;
1555 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1556 	u16 len_rthdr;
1557 	int hdrlen;
1558 
1559 	/* check for not even having the fixed radiotap header part */
1560 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1561 		goto fail; /* too short to be possibly valid */
1562 
1563 	/* is it a header version we can trust to find length from? */
1564 	if (unlikely(prthdr->it_version))
1565 		goto fail; /* only version 0 is supported */
1566 
1567 	/* then there must be a radiotap header with a length we can use */
1568 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1569 
1570 	/* does the skb contain enough to deliver on the alleged length? */
1571 	if (unlikely(skb->len < len_rthdr))
1572 		goto fail; /* skb too short for claimed rt header extent */
1573 
1574 	/*
1575 	 * fix up the pointers accounting for the radiotap
1576 	 * header still being in there.  We are being given
1577 	 * a precooked IEEE80211 header so no need for
1578 	 * normal processing
1579 	 */
1580 	skb_set_mac_header(skb, len_rthdr);
1581 	/*
1582 	 * these are just fixed to the end of the rt area since we
1583 	 * don't have any better information and at this point, nobody cares
1584 	 */
1585 	skb_set_network_header(skb, len_rthdr);
1586 	skb_set_transport_header(skb, len_rthdr);
1587 
1588 	if (skb->len < len_rthdr + 2)
1589 		goto fail;
1590 
1591 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1592 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1593 
1594 	if (skb->len < len_rthdr + hdrlen)
1595 		goto fail;
1596 
1597 	/*
1598 	 * Initialize skb->protocol if the injected frame is a data frame
1599 	 * carrying a rfc1042 header
1600 	 */
1601 	if (ieee80211_is_data(hdr->frame_control) &&
1602 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1603 		u8 *payload = (u8 *)hdr + hdrlen;
1604 
1605 		if (ether_addr_equal(payload, rfc1042_header))
1606 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1607 						    payload[7]);
1608 	}
1609 
1610 	memset(info, 0, sizeof(*info));
1611 
1612 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1613 		      IEEE80211_TX_CTL_INJECTED;
1614 
1615 	/* process and remove the injection radiotap header */
1616 	if (!ieee80211_parse_tx_radiotap(skb))
1617 		goto fail;
1618 
1619 	rcu_read_lock();
1620 
1621 	/*
1622 	 * We process outgoing injected frames that have a local address
1623 	 * we handle as though they are non-injected frames.
1624 	 * This code here isn't entirely correct, the local MAC address
1625 	 * isn't always enough to find the interface to use; for proper
1626 	 * VLAN/WDS support we will need a different mechanism (which
1627 	 * likely isn't going to be monitor interfaces).
1628 	 */
1629 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1630 
1631 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1632 		if (!ieee80211_sdata_running(tmp_sdata))
1633 			continue;
1634 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1635 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1636 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1637 			continue;
1638 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1639 			sdata = tmp_sdata;
1640 			break;
1641 		}
1642 	}
1643 
1644 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1645 	if (!chanctx_conf) {
1646 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1647 		if (tmp_sdata)
1648 			chanctx_conf =
1649 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1650 	}
1651 
1652 	if (chanctx_conf)
1653 		chan = chanctx_conf->def.chan;
1654 	else if (!local->use_chanctx)
1655 		chan = local->_oper_chandef.chan;
1656 	else
1657 		goto fail_rcu;
1658 
1659 	/*
1660 	 * Frame injection is not allowed if beaconing is not allowed
1661 	 * or if we need radar detection. Beaconing is usually not allowed when
1662 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1663 	 * Passive scan is also used in world regulatory domains where
1664 	 * your country is not known and as such it should be treated as
1665 	 * NO TX unless the channel is explicitly allowed in which case
1666 	 * your current regulatory domain would not have the passive scan
1667 	 * flag.
1668 	 *
1669 	 * Since AP mode uses monitor interfaces to inject/TX management
1670 	 * frames we can make AP mode the exception to this rule once it
1671 	 * supports radar detection as its implementation can deal with
1672 	 * radar detection by itself. We can do that later by adding a
1673 	 * monitor flag interfaces used for AP support.
1674 	 */
1675 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1676 			    IEEE80211_CHAN_PASSIVE_SCAN)))
1677 		goto fail_rcu;
1678 
1679 	ieee80211_xmit(sdata, skb, chan->band);
1680 	rcu_read_unlock();
1681 
1682 	return NETDEV_TX_OK;
1683 
1684 fail_rcu:
1685 	rcu_read_unlock();
1686 fail:
1687 	dev_kfree_skb(skb);
1688 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1689 }
1690 
1691 /**
1692  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1693  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1694  * @skb: packet to be sent
1695  * @dev: incoming interface
1696  *
1697  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1698  * not be freed, and caller is responsible for either retrying later or freeing
1699  * skb).
1700  *
1701  * This function takes in an Ethernet header and encapsulates it with suitable
1702  * IEEE 802.11 header based on which interface the packet is coming in. The
1703  * encapsulated packet will then be passed to master interface, wlan#.11, for
1704  * transmission (through low-level driver).
1705  */
1706 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1707 				    struct net_device *dev)
1708 {
1709 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1710 	struct ieee80211_local *local = sdata->local;
1711 	struct ieee80211_tx_info *info;
1712 	int head_need;
1713 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1714 	__le16 fc;
1715 	struct ieee80211_hdr hdr;
1716 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1717 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
1718 	const u8 *encaps_data;
1719 	int encaps_len, skip_header_bytes;
1720 	int nh_pos, h_pos;
1721 	struct sta_info *sta = NULL;
1722 	bool wme_sta = false, authorized = false, tdls_auth = false;
1723 	bool tdls_direct = false;
1724 	bool multicast;
1725 	u32 info_flags = 0;
1726 	u16 info_id = 0;
1727 	struct ieee80211_chanctx_conf *chanctx_conf;
1728 	struct ieee80211_sub_if_data *ap_sdata;
1729 	enum ieee80211_band band;
1730 
1731 	if (unlikely(skb->len < ETH_HLEN))
1732 		goto fail;
1733 
1734 	/* convert Ethernet header to proper 802.11 header (based on
1735 	 * operation mode) */
1736 	ethertype = (skb->data[12] << 8) | skb->data[13];
1737 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1738 
1739 	rcu_read_lock();
1740 
1741 	switch (sdata->vif.type) {
1742 	case NL80211_IFTYPE_AP_VLAN:
1743 		sta = rcu_dereference(sdata->u.vlan.sta);
1744 		if (sta) {
1745 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1746 			/* RA TA DA SA */
1747 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1748 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1749 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1750 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1751 			hdrlen = 30;
1752 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1753 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1754 		}
1755 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1756 					u.ap);
1757 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
1758 		if (!chanctx_conf)
1759 			goto fail_rcu;
1760 		band = chanctx_conf->def.chan->band;
1761 		if (sta)
1762 			break;
1763 		/* fall through */
1764 	case NL80211_IFTYPE_AP:
1765 		if (sdata->vif.type == NL80211_IFTYPE_AP)
1766 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1767 		if (!chanctx_conf)
1768 			goto fail_rcu;
1769 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1770 		/* DA BSSID SA */
1771 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1772 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1773 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1774 		hdrlen = 24;
1775 		band = chanctx_conf->def.chan->band;
1776 		break;
1777 	case NL80211_IFTYPE_WDS:
1778 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1779 		/* RA TA DA SA */
1780 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1781 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1782 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1783 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1784 		hdrlen = 30;
1785 		/*
1786 		 * This is the exception! WDS style interfaces are prohibited
1787 		 * when channel contexts are in used so this must be valid
1788 		 */
1789 		band = local->hw.conf.chandef.chan->band;
1790 		break;
1791 #ifdef CONFIG_MAC80211_MESH
1792 	case NL80211_IFTYPE_MESH_POINT:
1793 		if (!is_multicast_ether_addr(skb->data)) {
1794 			struct sta_info *next_hop;
1795 			bool mpp_lookup = true;
1796 
1797 			mpath = mesh_path_lookup(sdata, skb->data);
1798 			if (mpath) {
1799 				mpp_lookup = false;
1800 				next_hop = rcu_dereference(mpath->next_hop);
1801 				if (!next_hop ||
1802 				    !(mpath->flags & (MESH_PATH_ACTIVE |
1803 						      MESH_PATH_RESOLVING)))
1804 					mpp_lookup = true;
1805 			}
1806 
1807 			if (mpp_lookup)
1808 				mppath = mpp_path_lookup(sdata, skb->data);
1809 
1810 			if (mppath && mpath)
1811 				mesh_path_del(mpath->sdata, mpath->dst);
1812 		}
1813 
1814 		/*
1815 		 * Use address extension if it is a packet from
1816 		 * another interface or if we know the destination
1817 		 * is being proxied by a portal (i.e. portal address
1818 		 * differs from proxied address)
1819 		 */
1820 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
1821 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
1822 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1823 					skb->data, skb->data + ETH_ALEN);
1824 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
1825 							       NULL, NULL);
1826 		} else {
1827 			/* DS -> MBSS (802.11-2012 13.11.3.3).
1828 			 * For unicast with unknown forwarding information,
1829 			 * destination might be in the MBSS or if that fails
1830 			 * forwarded to another mesh gate. In either case
1831 			 * resolution will be handled in ieee80211_xmit(), so
1832 			 * leave the original DA. This also works for mcast */
1833 			const u8 *mesh_da = skb->data;
1834 
1835 			if (mppath)
1836 				mesh_da = mppath->mpp;
1837 			else if (mpath)
1838 				mesh_da = mpath->dst;
1839 
1840 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1841 					mesh_da, sdata->vif.addr);
1842 			if (is_multicast_ether_addr(mesh_da))
1843 				/* DA TA mSA AE:SA */
1844 				meshhdrlen = ieee80211_new_mesh_header(
1845 						sdata, &mesh_hdr,
1846 						skb->data + ETH_ALEN, NULL);
1847 			else
1848 				/* RA TA mDA mSA AE:DA SA */
1849 				meshhdrlen = ieee80211_new_mesh_header(
1850 						sdata, &mesh_hdr, skb->data,
1851 						skb->data + ETH_ALEN);
1852 
1853 		}
1854 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1855 		if (!chanctx_conf)
1856 			goto fail_rcu;
1857 		band = chanctx_conf->def.chan->band;
1858 		break;
1859 #endif
1860 	case NL80211_IFTYPE_STATION:
1861 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1862 			bool tdls_peer = false;
1863 
1864 			sta = sta_info_get(sdata, skb->data);
1865 			if (sta) {
1866 				authorized = test_sta_flag(sta,
1867 							WLAN_STA_AUTHORIZED);
1868 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1869 				tdls_peer = test_sta_flag(sta,
1870 							 WLAN_STA_TDLS_PEER);
1871 				tdls_auth = test_sta_flag(sta,
1872 						WLAN_STA_TDLS_PEER_AUTH);
1873 			}
1874 
1875 			/*
1876 			 * If the TDLS link is enabled, send everything
1877 			 * directly. Otherwise, allow TDLS setup frames
1878 			 * to be transmitted indirectly.
1879 			 */
1880 			tdls_direct = tdls_peer && (tdls_auth ||
1881 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1882 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1883 		}
1884 
1885 		if (tdls_direct) {
1886 			/* link during setup - throw out frames to peer */
1887 			if (!tdls_auth)
1888 				goto fail_rcu;
1889 
1890 			/* DA SA BSSID */
1891 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1892 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1893 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1894 			hdrlen = 24;
1895 		}  else if (sdata->u.mgd.use_4addr &&
1896 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1897 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1898 					  IEEE80211_FCTL_TODS);
1899 			/* RA TA DA SA */
1900 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1901 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1902 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1903 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1904 			hdrlen = 30;
1905 		} else {
1906 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1907 			/* BSSID SA DA */
1908 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1909 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1910 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1911 			hdrlen = 24;
1912 		}
1913 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1914 		if (!chanctx_conf)
1915 			goto fail_rcu;
1916 		band = chanctx_conf->def.chan->band;
1917 		break;
1918 	case NL80211_IFTYPE_ADHOC:
1919 		/* DA SA BSSID */
1920 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1921 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1922 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1923 		hdrlen = 24;
1924 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1925 		if (!chanctx_conf)
1926 			goto fail_rcu;
1927 		band = chanctx_conf->def.chan->band;
1928 		break;
1929 	default:
1930 		goto fail_rcu;
1931 	}
1932 
1933 	/*
1934 	 * There's no need to try to look up the destination
1935 	 * if it is a multicast address (which can only happen
1936 	 * in AP mode)
1937 	 */
1938 	multicast = is_multicast_ether_addr(hdr.addr1);
1939 	if (!multicast) {
1940 		sta = sta_info_get(sdata, hdr.addr1);
1941 		if (sta) {
1942 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1943 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1944 		}
1945 	}
1946 
1947 	/* For mesh, the use of the QoS header is mandatory */
1948 	if (ieee80211_vif_is_mesh(&sdata->vif))
1949 		wme_sta = true;
1950 
1951 	/* receiver and we are QoS enabled, use a QoS type frame */
1952 	if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
1953 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1954 		hdrlen += 2;
1955 	}
1956 
1957 	/*
1958 	 * Drop unicast frames to unauthorised stations unless they are
1959 	 * EAPOL frames from the local station.
1960 	 */
1961 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
1962 		     !is_multicast_ether_addr(hdr.addr1) && !authorized &&
1963 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
1964 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
1965 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1966 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
1967 				    dev->name, hdr.addr1);
1968 #endif
1969 
1970 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1971 
1972 		goto fail_rcu;
1973 	}
1974 
1975 	if (unlikely(!multicast && skb->sk &&
1976 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
1977 		struct sk_buff *orig_skb = skb;
1978 
1979 		skb = skb_clone(skb, GFP_ATOMIC);
1980 		if (skb) {
1981 			unsigned long flags;
1982 			int id;
1983 
1984 			spin_lock_irqsave(&local->ack_status_lock, flags);
1985 			id = idr_alloc(&local->ack_status_frames, orig_skb,
1986 				       1, 0x10000, GFP_ATOMIC);
1987 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
1988 
1989 			if (id >= 0) {
1990 				info_id = id;
1991 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1992 			} else if (skb_shared(skb)) {
1993 				kfree_skb(orig_skb);
1994 			} else {
1995 				kfree_skb(skb);
1996 				skb = orig_skb;
1997 			}
1998 		} else {
1999 			/* couldn't clone -- lose tx status ... */
2000 			skb = orig_skb;
2001 		}
2002 	}
2003 
2004 	/*
2005 	 * If the skb is shared we need to obtain our own copy.
2006 	 */
2007 	if (skb_shared(skb)) {
2008 		struct sk_buff *tmp_skb = skb;
2009 
2010 		/* can't happen -- skb is a clone if info_id != 0 */
2011 		WARN_ON(info_id);
2012 
2013 		skb = skb_clone(skb, GFP_ATOMIC);
2014 		kfree_skb(tmp_skb);
2015 
2016 		if (!skb)
2017 			goto fail_rcu;
2018 	}
2019 
2020 	hdr.frame_control = fc;
2021 	hdr.duration_id = 0;
2022 	hdr.seq_ctrl = 0;
2023 
2024 	skip_header_bytes = ETH_HLEN;
2025 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2026 		encaps_data = bridge_tunnel_header;
2027 		encaps_len = sizeof(bridge_tunnel_header);
2028 		skip_header_bytes -= 2;
2029 	} else if (ethertype >= ETH_P_802_3_MIN) {
2030 		encaps_data = rfc1042_header;
2031 		encaps_len = sizeof(rfc1042_header);
2032 		skip_header_bytes -= 2;
2033 	} else {
2034 		encaps_data = NULL;
2035 		encaps_len = 0;
2036 	}
2037 
2038 	nh_pos = skb_network_header(skb) - skb->data;
2039 	h_pos = skb_transport_header(skb) - skb->data;
2040 
2041 	skb_pull(skb, skip_header_bytes);
2042 	nh_pos -= skip_header_bytes;
2043 	h_pos -= skip_header_bytes;
2044 
2045 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2046 
2047 	/*
2048 	 * So we need to modify the skb header and hence need a copy of
2049 	 * that. The head_need variable above doesn't, so far, include
2050 	 * the needed header space that we don't need right away. If we
2051 	 * can, then we don't reallocate right now but only after the
2052 	 * frame arrives at the master device (if it does...)
2053 	 *
2054 	 * If we cannot, however, then we will reallocate to include all
2055 	 * the ever needed space. Also, if we need to reallocate it anyway,
2056 	 * make it big enough for everything we may ever need.
2057 	 */
2058 
2059 	if (head_need > 0 || skb_cloned(skb)) {
2060 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2061 		head_need += local->tx_headroom;
2062 		head_need = max_t(int, 0, head_need);
2063 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2064 			ieee80211_free_txskb(&local->hw, skb);
2065 			skb = NULL;
2066 			goto fail_rcu;
2067 		}
2068 	}
2069 
2070 	if (encaps_data) {
2071 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2072 		nh_pos += encaps_len;
2073 		h_pos += encaps_len;
2074 	}
2075 
2076 #ifdef CONFIG_MAC80211_MESH
2077 	if (meshhdrlen > 0) {
2078 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2079 		nh_pos += meshhdrlen;
2080 		h_pos += meshhdrlen;
2081 	}
2082 #endif
2083 
2084 	if (ieee80211_is_data_qos(fc)) {
2085 		__le16 *qos_control;
2086 
2087 		qos_control = (__le16*) skb_push(skb, 2);
2088 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2089 		/*
2090 		 * Maybe we could actually set some fields here, for now just
2091 		 * initialise to zero to indicate no special operation.
2092 		 */
2093 		*qos_control = 0;
2094 	} else
2095 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2096 
2097 	nh_pos += hdrlen;
2098 	h_pos += hdrlen;
2099 
2100 	dev->stats.tx_packets++;
2101 	dev->stats.tx_bytes += skb->len;
2102 
2103 	/* Update skb pointers to various headers since this modified frame
2104 	 * is going to go through Linux networking code that may potentially
2105 	 * need things like pointer to IP header. */
2106 	skb_set_mac_header(skb, 0);
2107 	skb_set_network_header(skb, nh_pos);
2108 	skb_set_transport_header(skb, h_pos);
2109 
2110 	info = IEEE80211_SKB_CB(skb);
2111 	memset(info, 0, sizeof(*info));
2112 
2113 	dev->trans_start = jiffies;
2114 
2115 	info->flags = info_flags;
2116 	info->ack_frame_id = info_id;
2117 
2118 	ieee80211_xmit(sdata, skb, band);
2119 	rcu_read_unlock();
2120 
2121 	return NETDEV_TX_OK;
2122 
2123  fail_rcu:
2124 	rcu_read_unlock();
2125  fail:
2126 	dev_kfree_skb(skb);
2127 	return NETDEV_TX_OK;
2128 }
2129 
2130 
2131 /*
2132  * ieee80211_clear_tx_pending may not be called in a context where
2133  * it is possible that it packets could come in again.
2134  */
2135 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2136 {
2137 	struct sk_buff *skb;
2138 	int i;
2139 
2140 	for (i = 0; i < local->hw.queues; i++) {
2141 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
2142 			ieee80211_free_txskb(&local->hw, skb);
2143 	}
2144 }
2145 
2146 /*
2147  * Returns false if the frame couldn't be transmitted but was queued instead,
2148  * which in this case means re-queued -- take as an indication to stop sending
2149  * more pending frames.
2150  */
2151 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2152 				     struct sk_buff *skb)
2153 {
2154 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2155 	struct ieee80211_sub_if_data *sdata;
2156 	struct sta_info *sta;
2157 	struct ieee80211_hdr *hdr;
2158 	bool result;
2159 	struct ieee80211_chanctx_conf *chanctx_conf;
2160 
2161 	sdata = vif_to_sdata(info->control.vif);
2162 
2163 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2164 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2165 		if (unlikely(!chanctx_conf)) {
2166 			dev_kfree_skb(skb);
2167 			return true;
2168 		}
2169 		result = ieee80211_tx(sdata, skb, true,
2170 				      chanctx_conf->def.chan->band);
2171 	} else {
2172 		struct sk_buff_head skbs;
2173 
2174 		__skb_queue_head_init(&skbs);
2175 		__skb_queue_tail(&skbs, skb);
2176 
2177 		hdr = (struct ieee80211_hdr *)skb->data;
2178 		sta = sta_info_get(sdata, hdr->addr1);
2179 
2180 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2181 	}
2182 
2183 	return result;
2184 }
2185 
2186 /*
2187  * Transmit all pending packets. Called from tasklet.
2188  */
2189 void ieee80211_tx_pending(unsigned long data)
2190 {
2191 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2192 	unsigned long flags;
2193 	int i;
2194 	bool txok;
2195 
2196 	rcu_read_lock();
2197 
2198 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2199 	for (i = 0; i < local->hw.queues; i++) {
2200 		/*
2201 		 * If queue is stopped by something other than due to pending
2202 		 * frames, or we have no pending frames, proceed to next queue.
2203 		 */
2204 		if (local->queue_stop_reasons[i] ||
2205 		    skb_queue_empty(&local->pending[i]))
2206 			continue;
2207 
2208 		while (!skb_queue_empty(&local->pending[i])) {
2209 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2210 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2211 
2212 			if (WARN_ON(!info->control.vif)) {
2213 				ieee80211_free_txskb(&local->hw, skb);
2214 				continue;
2215 			}
2216 
2217 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2218 						flags);
2219 
2220 			txok = ieee80211_tx_pending_skb(local, skb);
2221 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2222 					  flags);
2223 			if (!txok)
2224 				break;
2225 		}
2226 
2227 		if (skb_queue_empty(&local->pending[i]))
2228 			ieee80211_propagate_queue_wake(local, i);
2229 	}
2230 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2231 
2232 	rcu_read_unlock();
2233 }
2234 
2235 /* functions for drivers to get certain frames */
2236 
2237 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2238 				       struct ps_data *ps, struct sk_buff *skb)
2239 {
2240 	u8 *pos, *tim;
2241 	int aid0 = 0;
2242 	int i, have_bits = 0, n1, n2;
2243 
2244 	/* Generate bitmap for TIM only if there are any STAs in power save
2245 	 * mode. */
2246 	if (atomic_read(&ps->num_sta_ps) > 0)
2247 		/* in the hope that this is faster than
2248 		 * checking byte-for-byte */
2249 		have_bits = !bitmap_empty((unsigned long*)ps->tim,
2250 					  IEEE80211_MAX_AID+1);
2251 
2252 	if (ps->dtim_count == 0)
2253 		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
2254 	else
2255 		ps->dtim_count--;
2256 
2257 	tim = pos = (u8 *) skb_put(skb, 6);
2258 	*pos++ = WLAN_EID_TIM;
2259 	*pos++ = 4;
2260 	*pos++ = ps->dtim_count;
2261 	*pos++ = sdata->vif.bss_conf.dtim_period;
2262 
2263 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
2264 		aid0 = 1;
2265 
2266 	ps->dtim_bc_mc = aid0 == 1;
2267 
2268 	if (have_bits) {
2269 		/* Find largest even number N1 so that bits numbered 1 through
2270 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2271 		 * (N2 + 1) x 8 through 2007 are 0. */
2272 		n1 = 0;
2273 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2274 			if (ps->tim[i]) {
2275 				n1 = i & 0xfe;
2276 				break;
2277 			}
2278 		}
2279 		n2 = n1;
2280 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2281 			if (ps->tim[i]) {
2282 				n2 = i;
2283 				break;
2284 			}
2285 		}
2286 
2287 		/* Bitmap control */
2288 		*pos++ = n1 | aid0;
2289 		/* Part Virt Bitmap */
2290 		skb_put(skb, n2 - n1);
2291 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
2292 
2293 		tim[1] = n2 - n1 + 4;
2294 	} else {
2295 		*pos++ = aid0; /* Bitmap control */
2296 		*pos++ = 0; /* Part Virt Bitmap */
2297 	}
2298 }
2299 
2300 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2301 				    struct ps_data *ps, struct sk_buff *skb)
2302 {
2303 	struct ieee80211_local *local = sdata->local;
2304 
2305 	/*
2306 	 * Not very nice, but we want to allow the driver to call
2307 	 * ieee80211_beacon_get() as a response to the set_tim()
2308 	 * callback. That, however, is already invoked under the
2309 	 * sta_lock to guarantee consistent and race-free update
2310 	 * of the tim bitmap in mac80211 and the driver.
2311 	 */
2312 	if (local->tim_in_locked_section) {
2313 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2314 	} else {
2315 		spin_lock_bh(&local->tim_lock);
2316 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2317 		spin_unlock_bh(&local->tim_lock);
2318 	}
2319 
2320 	return 0;
2321 }
2322 
2323 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2324 					 struct ieee80211_vif *vif,
2325 					 u16 *tim_offset, u16 *tim_length)
2326 {
2327 	struct ieee80211_local *local = hw_to_local(hw);
2328 	struct sk_buff *skb = NULL;
2329 	struct ieee80211_tx_info *info;
2330 	struct ieee80211_sub_if_data *sdata = NULL;
2331 	enum ieee80211_band band;
2332 	struct ieee80211_tx_rate_control txrc;
2333 	struct ieee80211_chanctx_conf *chanctx_conf;
2334 
2335 	rcu_read_lock();
2336 
2337 	sdata = vif_to_sdata(vif);
2338 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2339 
2340 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
2341 		goto out;
2342 
2343 	if (tim_offset)
2344 		*tim_offset = 0;
2345 	if (tim_length)
2346 		*tim_length = 0;
2347 
2348 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2349 		struct ieee80211_if_ap *ap = &sdata->u.ap;
2350 		struct beacon_data *beacon = rcu_dereference(ap->beacon);
2351 
2352 		if (beacon) {
2353 			/*
2354 			 * headroom, head length,
2355 			 * tail length and maximum TIM length
2356 			 */
2357 			skb = dev_alloc_skb(local->tx_headroom +
2358 					    beacon->head_len +
2359 					    beacon->tail_len + 256);
2360 			if (!skb)
2361 				goto out;
2362 
2363 			skb_reserve(skb, local->tx_headroom);
2364 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2365 			       beacon->head_len);
2366 
2367 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
2368 
2369 			if (tim_offset)
2370 				*tim_offset = beacon->head_len;
2371 			if (tim_length)
2372 				*tim_length = skb->len - beacon->head_len;
2373 
2374 			if (beacon->tail)
2375 				memcpy(skb_put(skb, beacon->tail_len),
2376 				       beacon->tail, beacon->tail_len);
2377 		} else
2378 			goto out;
2379 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2380 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2381 		struct ieee80211_hdr *hdr;
2382 		struct beacon_data *presp = rcu_dereference(ifibss->presp);
2383 
2384 		if (!presp)
2385 			goto out;
2386 
2387 		skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
2388 		if (!skb)
2389 			goto out;
2390 		skb_reserve(skb, local->tx_headroom);
2391 		memcpy(skb_put(skb, presp->head_len), presp->head,
2392 		       presp->head_len);
2393 
2394 		hdr = (struct ieee80211_hdr *) skb->data;
2395 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2396 						 IEEE80211_STYPE_BEACON);
2397 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2398 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2399 		struct beacon_data *bcn = rcu_dereference(ifmsh->beacon);
2400 
2401 		if (!bcn)
2402 			goto out;
2403 
2404 		if (ifmsh->sync_ops)
2405 			ifmsh->sync_ops->adjust_tbtt(
2406 						sdata);
2407 
2408 		skb = dev_alloc_skb(local->tx_headroom +
2409 				    bcn->head_len +
2410 				    256 + /* TIM IE */
2411 				    bcn->tail_len);
2412 		if (!skb)
2413 			goto out;
2414 		skb_reserve(skb, local->tx_headroom);
2415 		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
2416 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
2417 		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
2418 	} else {
2419 		WARN_ON(1);
2420 		goto out;
2421 	}
2422 
2423 	band = chanctx_conf->def.chan->band;
2424 
2425 	info = IEEE80211_SKB_CB(skb);
2426 
2427 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2428 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2429 	info->band = band;
2430 
2431 	memset(&txrc, 0, sizeof(txrc));
2432 	txrc.hw = hw;
2433 	txrc.sband = local->hw.wiphy->bands[band];
2434 	txrc.bss_conf = &sdata->vif.bss_conf;
2435 	txrc.skb = skb;
2436 	txrc.reported_rate.idx = -1;
2437 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2438 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
2439 		txrc.max_rate_idx = -1;
2440 	else
2441 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2442 	txrc.bss = true;
2443 	rate_control_get_rate(sdata, NULL, &txrc);
2444 
2445 	info->control.vif = vif;
2446 
2447 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2448 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2449 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2450  out:
2451 	rcu_read_unlock();
2452 	return skb;
2453 }
2454 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2455 
2456 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
2457 					struct ieee80211_vif *vif)
2458 {
2459 	struct ieee80211_if_ap *ap = NULL;
2460 	struct sk_buff *skb = NULL;
2461 	struct probe_resp *presp = NULL;
2462 	struct ieee80211_hdr *hdr;
2463 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2464 
2465 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2466 		return NULL;
2467 
2468 	rcu_read_lock();
2469 
2470 	ap = &sdata->u.ap;
2471 	presp = rcu_dereference(ap->probe_resp);
2472 	if (!presp)
2473 		goto out;
2474 
2475 	skb = dev_alloc_skb(presp->len);
2476 	if (!skb)
2477 		goto out;
2478 
2479 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
2480 
2481 	hdr = (struct ieee80211_hdr *) skb->data;
2482 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2483 
2484 out:
2485 	rcu_read_unlock();
2486 	return skb;
2487 }
2488 EXPORT_SYMBOL(ieee80211_proberesp_get);
2489 
2490 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2491 				     struct ieee80211_vif *vif)
2492 {
2493 	struct ieee80211_sub_if_data *sdata;
2494 	struct ieee80211_if_managed *ifmgd;
2495 	struct ieee80211_pspoll *pspoll;
2496 	struct ieee80211_local *local;
2497 	struct sk_buff *skb;
2498 
2499 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2500 		return NULL;
2501 
2502 	sdata = vif_to_sdata(vif);
2503 	ifmgd = &sdata->u.mgd;
2504 	local = sdata->local;
2505 
2506 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2507 	if (!skb)
2508 		return NULL;
2509 
2510 	skb_reserve(skb, local->hw.extra_tx_headroom);
2511 
2512 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2513 	memset(pspoll, 0, sizeof(*pspoll));
2514 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2515 					    IEEE80211_STYPE_PSPOLL);
2516 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2517 
2518 	/* aid in PS-Poll has its two MSBs each set to 1 */
2519 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2520 
2521 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2522 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2523 
2524 	return skb;
2525 }
2526 EXPORT_SYMBOL(ieee80211_pspoll_get);
2527 
2528 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2529 				       struct ieee80211_vif *vif)
2530 {
2531 	struct ieee80211_hdr_3addr *nullfunc;
2532 	struct ieee80211_sub_if_data *sdata;
2533 	struct ieee80211_if_managed *ifmgd;
2534 	struct ieee80211_local *local;
2535 	struct sk_buff *skb;
2536 
2537 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2538 		return NULL;
2539 
2540 	sdata = vif_to_sdata(vif);
2541 	ifmgd = &sdata->u.mgd;
2542 	local = sdata->local;
2543 
2544 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2545 	if (!skb)
2546 		return NULL;
2547 
2548 	skb_reserve(skb, local->hw.extra_tx_headroom);
2549 
2550 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2551 							  sizeof(*nullfunc));
2552 	memset(nullfunc, 0, sizeof(*nullfunc));
2553 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2554 					      IEEE80211_STYPE_NULLFUNC |
2555 					      IEEE80211_FCTL_TODS);
2556 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2557 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2558 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2559 
2560 	return skb;
2561 }
2562 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2563 
2564 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2565 				       struct ieee80211_vif *vif,
2566 				       const u8 *ssid, size_t ssid_len,
2567 				       size_t tailroom)
2568 {
2569 	struct ieee80211_sub_if_data *sdata;
2570 	struct ieee80211_local *local;
2571 	struct ieee80211_hdr_3addr *hdr;
2572 	struct sk_buff *skb;
2573 	size_t ie_ssid_len;
2574 	u8 *pos;
2575 
2576 	sdata = vif_to_sdata(vif);
2577 	local = sdata->local;
2578 	ie_ssid_len = 2 + ssid_len;
2579 
2580 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2581 			    ie_ssid_len + tailroom);
2582 	if (!skb)
2583 		return NULL;
2584 
2585 	skb_reserve(skb, local->hw.extra_tx_headroom);
2586 
2587 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2588 	memset(hdr, 0, sizeof(*hdr));
2589 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2590 					 IEEE80211_STYPE_PROBE_REQ);
2591 	eth_broadcast_addr(hdr->addr1);
2592 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2593 	eth_broadcast_addr(hdr->addr3);
2594 
2595 	pos = skb_put(skb, ie_ssid_len);
2596 	*pos++ = WLAN_EID_SSID;
2597 	*pos++ = ssid_len;
2598 	if (ssid_len)
2599 		memcpy(pos, ssid, ssid_len);
2600 	pos += ssid_len;
2601 
2602 	return skb;
2603 }
2604 EXPORT_SYMBOL(ieee80211_probereq_get);
2605 
2606 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2607 		       const void *frame, size_t frame_len,
2608 		       const struct ieee80211_tx_info *frame_txctl,
2609 		       struct ieee80211_rts *rts)
2610 {
2611 	const struct ieee80211_hdr *hdr = frame;
2612 
2613 	rts->frame_control =
2614 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2615 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2616 					       frame_txctl);
2617 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2618 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2619 }
2620 EXPORT_SYMBOL(ieee80211_rts_get);
2621 
2622 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2623 			     const void *frame, size_t frame_len,
2624 			     const struct ieee80211_tx_info *frame_txctl,
2625 			     struct ieee80211_cts *cts)
2626 {
2627 	const struct ieee80211_hdr *hdr = frame;
2628 
2629 	cts->frame_control =
2630 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2631 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2632 						     frame_len, frame_txctl);
2633 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2634 }
2635 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2636 
2637 struct sk_buff *
2638 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2639 			  struct ieee80211_vif *vif)
2640 {
2641 	struct ieee80211_local *local = hw_to_local(hw);
2642 	struct sk_buff *skb = NULL;
2643 	struct ieee80211_tx_data tx;
2644 	struct ieee80211_sub_if_data *sdata;
2645 	struct ps_data *ps;
2646 	struct ieee80211_tx_info *info;
2647 	struct ieee80211_chanctx_conf *chanctx_conf;
2648 
2649 	sdata = vif_to_sdata(vif);
2650 
2651 	rcu_read_lock();
2652 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2653 
2654 	if (!chanctx_conf)
2655 		goto out;
2656 
2657 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2658 		struct beacon_data *beacon =
2659 				rcu_dereference(sdata->u.ap.beacon);
2660 
2661 		if (!beacon || !beacon->head)
2662 			goto out;
2663 
2664 		ps = &sdata->u.ap.ps;
2665 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2666 		ps = &sdata->u.mesh.ps;
2667 	} else {
2668 		goto out;
2669 	}
2670 
2671 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
2672 		goto out; /* send buffered bc/mc only after DTIM beacon */
2673 
2674 	while (1) {
2675 		skb = skb_dequeue(&ps->bc_buf);
2676 		if (!skb)
2677 			goto out;
2678 		local->total_ps_buffered--;
2679 
2680 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
2681 			struct ieee80211_hdr *hdr =
2682 				(struct ieee80211_hdr *) skb->data;
2683 			/* more buffered multicast/broadcast frames ==> set
2684 			 * MoreData flag in IEEE 802.11 header to inform PS
2685 			 * STAs */
2686 			hdr->frame_control |=
2687 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2688 		}
2689 
2690 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2691 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
2692 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2693 			break;
2694 		dev_kfree_skb_any(skb);
2695 	}
2696 
2697 	info = IEEE80211_SKB_CB(skb);
2698 
2699 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2700 	info->band = chanctx_conf->def.chan->band;
2701 
2702 	if (invoke_tx_handlers(&tx))
2703 		skb = NULL;
2704  out:
2705 	rcu_read_unlock();
2706 
2707 	return skb;
2708 }
2709 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2710 
2711 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
2712 				 struct sk_buff *skb, int tid,
2713 				 enum ieee80211_band band)
2714 {
2715 	int ac = ieee802_1d_to_ac[tid & 7];
2716 
2717 	skb_set_mac_header(skb, 0);
2718 	skb_set_network_header(skb, 0);
2719 	skb_set_transport_header(skb, 0);
2720 
2721 	skb_set_queue_mapping(skb, ac);
2722 	skb->priority = tid;
2723 
2724 	skb->dev = sdata->dev;
2725 
2726 	/*
2727 	 * The other path calling ieee80211_xmit is from the tasklet,
2728 	 * and while we can handle concurrent transmissions locking
2729 	 * requirements are that we do not come into tx with bhs on.
2730 	 */
2731 	local_bh_disable();
2732 	ieee80211_xmit(sdata, skb, band);
2733 	local_bh_enable();
2734 }
2735