xref: /openbmc/linux/net/mac80211/tx.c (revision dbf498fbafa2c23139d5a990e94ed78bafbbea19)
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 (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
52 		return 0;
53 
54 	/* uh huh? */
55 	if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
56 		return 0;
57 
58 	sband = local->hw.wiphy->bands[tx->channel->band];
59 	txrate = &sband->bitrates[info->control.rates[0].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_NUM_BANDS:
144 			WARN_ON(1);
145 			break;
146 		}
147 	}
148 	if (rate == -1) {
149 		/* No matching basic rate found; use highest suitable mandatory
150 		 * PHY rate */
151 		rate = mrate;
152 	}
153 
154 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
155 	if (ieee80211_is_data_qos(hdr->frame_control) &&
156 	    *(ieee80211_get_qos_ctl(hdr)) | IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
157 		dur = 0;
158 	else
159 		/* Time needed to transmit ACK
160 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
161 		 * to closest integer */
162 		dur = ieee80211_frame_duration(local, 10, rate, erp,
163 				tx->sdata->vif.bss_conf.use_short_preamble);
164 
165 	if (next_frag_len) {
166 		/* Frame is fragmented: duration increases with time needed to
167 		 * transmit next fragment plus ACK and 2 x SIFS. */
168 		dur *= 2; /* ACK + SIFS */
169 		/* next fragment */
170 		dur += ieee80211_frame_duration(local, next_frag_len,
171 				txrate->bitrate, erp,
172 				tx->sdata->vif.bss_conf.use_short_preamble);
173 	}
174 
175 	return cpu_to_le16(dur);
176 }
177 
178 static inline int is_ieee80211_device(struct ieee80211_local *local,
179 				      struct net_device *dev)
180 {
181 	return local == wdev_priv(dev->ieee80211_ptr);
182 }
183 
184 /* tx handlers */
185 static ieee80211_tx_result debug_noinline
186 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
187 {
188 	struct ieee80211_local *local = tx->local;
189 	struct ieee80211_if_managed *ifmgd;
190 
191 	/* driver doesn't support power save */
192 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
193 		return TX_CONTINUE;
194 
195 	/* hardware does dynamic power save */
196 	if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
197 		return TX_CONTINUE;
198 
199 	/* dynamic power save disabled */
200 	if (local->hw.conf.dynamic_ps_timeout <= 0)
201 		return TX_CONTINUE;
202 
203 	/* we are scanning, don't enable power save */
204 	if (local->scanning)
205 		return TX_CONTINUE;
206 
207 	if (!local->ps_sdata)
208 		return TX_CONTINUE;
209 
210 	/* No point if we're going to suspend */
211 	if (local->quiescing)
212 		return TX_CONTINUE;
213 
214 	/* dynamic ps is supported only in managed mode */
215 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
216 		return TX_CONTINUE;
217 
218 	ifmgd = &tx->sdata->u.mgd;
219 
220 	/*
221 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
222 	 * u-apsd enabled and the frame is in voip class. This effectively
223 	 * means that even if all access categories have u-apsd enabled, in
224 	 * practise u-apsd is only used with the voip ac. This is a
225 	 * workaround for the case when received voip class packets do not
226 	 * have correct qos tag for some reason, due the network or the
227 	 * peer application.
228 	 *
229 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
230 	 * changed via debugfs, user needs to reassociate manually to have
231 	 * everything in sync.
232 	 */
233 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
234 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
235 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
236 		return TX_CONTINUE;
237 
238 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
239 		ieee80211_stop_queues_by_reason(&local->hw,
240 						IEEE80211_QUEUE_STOP_REASON_PS);
241 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
242 		ieee80211_queue_work(&local->hw,
243 				     &local->dynamic_ps_disable_work);
244 	}
245 
246 	/* Don't restart the timer if we're not disassociated */
247 	if (!ifmgd->associated)
248 		return TX_CONTINUE;
249 
250 	mod_timer(&local->dynamic_ps_timer, jiffies +
251 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
252 
253 	return TX_CONTINUE;
254 }
255 
256 static ieee80211_tx_result debug_noinline
257 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
258 {
259 
260 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
261 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
262 	bool assoc = false;
263 
264 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
265 		return TX_CONTINUE;
266 
267 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
268 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
269 	    !ieee80211_is_probe_req(hdr->frame_control) &&
270 	    !ieee80211_is_nullfunc(hdr->frame_control))
271 		/*
272 		 * When software scanning only nullfunc frames (to notify
273 		 * the sleep state to the AP) and probe requests (for the
274 		 * active scan) are allowed, all other frames should not be
275 		 * sent and we should not get here, but if we do
276 		 * nonetheless, drop them to avoid sending them
277 		 * off-channel. See the link below and
278 		 * ieee80211_start_scan() for more.
279 		 *
280 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
281 		 */
282 		return TX_DROP;
283 
284 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
285 		return TX_CONTINUE;
286 
287 	if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
288 		return TX_CONTINUE;
289 
290 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
291 		return TX_CONTINUE;
292 
293 	if (tx->sta)
294 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
295 
296 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
297 		if (unlikely(!assoc &&
298 			     ieee80211_is_data(hdr->frame_control))) {
299 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
300 			printk(KERN_DEBUG "%s: dropped data frame to not "
301 			       "associated station %pM\n",
302 			       tx->sdata->name, hdr->addr1);
303 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
304 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
305 			return TX_DROP;
306 		}
307 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
308 			    ieee80211_is_data(hdr->frame_control) &&
309 			    !atomic_read(&tx->sdata->u.ap.num_sta_authorized))) {
310 		/*
311 		 * No associated STAs - no need to send multicast
312 		 * frames.
313 		 */
314 		return TX_DROP;
315 	}
316 
317 	return TX_CONTINUE;
318 }
319 
320 /* This function is called whenever the AP is about to exceed the maximum limit
321  * of buffered frames for power saving STAs. This situation should not really
322  * happen often during normal operation, so dropping the oldest buffered packet
323  * from each queue should be OK to make some room for new frames. */
324 static void purge_old_ps_buffers(struct ieee80211_local *local)
325 {
326 	int total = 0, purged = 0;
327 	struct sk_buff *skb;
328 	struct ieee80211_sub_if_data *sdata;
329 	struct sta_info *sta;
330 
331 	/*
332 	 * virtual interfaces are protected by RCU
333 	 */
334 	rcu_read_lock();
335 
336 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
337 		struct ieee80211_if_ap *ap;
338 		if (sdata->vif.type != NL80211_IFTYPE_AP)
339 			continue;
340 		ap = &sdata->u.ap;
341 		skb = skb_dequeue(&ap->ps_bc_buf);
342 		if (skb) {
343 			purged++;
344 			dev_kfree_skb(skb);
345 		}
346 		total += skb_queue_len(&ap->ps_bc_buf);
347 	}
348 
349 	/*
350 	 * Drop one frame from each station from the lowest-priority
351 	 * AC that has frames at all.
352 	 */
353 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
354 		int ac;
355 
356 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
357 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
358 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
359 			if (skb) {
360 				purged++;
361 				dev_kfree_skb(skb);
362 				break;
363 			}
364 		}
365 	}
366 
367 	rcu_read_unlock();
368 
369 	local->total_ps_buffered = total;
370 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
371 	wiphy_debug(local->hw.wiphy, "PS buffers full - purged %d frames\n",
372 		    purged);
373 #endif
374 }
375 
376 static ieee80211_tx_result
377 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
378 {
379 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
380 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
381 
382 	/*
383 	 * broadcast/multicast frame
384 	 *
385 	 * If any of the associated stations is in power save mode,
386 	 * the frame is buffered to be sent after DTIM beacon frame.
387 	 * This is done either by the hardware or us.
388 	 */
389 
390 	/* powersaving STAs only in AP/VLAN mode */
391 	if (!tx->sdata->bss)
392 		return TX_CONTINUE;
393 
394 	/* no buffering for ordered frames */
395 	if (ieee80211_has_order(hdr->frame_control))
396 		return TX_CONTINUE;
397 
398 	/* no stations in PS mode */
399 	if (!atomic_read(&tx->sdata->bss->num_sta_ps))
400 		return TX_CONTINUE;
401 
402 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
403 
404 	/* device releases frame after DTIM beacon */
405 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
406 		return TX_CONTINUE;
407 
408 	/* buffered in mac80211 */
409 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
410 		purge_old_ps_buffers(tx->local);
411 
412 	if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
413 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
414 		if (net_ratelimit())
415 			printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n",
416 			       tx->sdata->name);
417 #endif
418 		dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
419 	} else
420 		tx->local->total_ps_buffered++;
421 
422 	skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
423 
424 	return TX_QUEUED;
425 }
426 
427 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
428 			     struct sk_buff *skb)
429 {
430 	if (!ieee80211_is_mgmt(fc))
431 		return 0;
432 
433 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
434 		return 0;
435 
436 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
437 					    skb->data))
438 		return 0;
439 
440 	return 1;
441 }
442 
443 static ieee80211_tx_result
444 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
445 {
446 	struct sta_info *sta = tx->sta;
447 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
448 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
449 	struct ieee80211_local *local = tx->local;
450 
451 	if (unlikely(!sta))
452 		return TX_CONTINUE;
453 
454 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
455 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
456 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
457 		int ac = skb_get_queue_mapping(tx->skb);
458 
459 		/* only deauth, disassoc and action are bufferable MMPDUs */
460 		if (ieee80211_is_mgmt(hdr->frame_control) &&
461 		    !ieee80211_is_deauth(hdr->frame_control) &&
462 		    !ieee80211_is_disassoc(hdr->frame_control) &&
463 		    !ieee80211_is_action(hdr->frame_control)) {
464 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
465 			return TX_CONTINUE;
466 		}
467 
468 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
469 		printk(KERN_DEBUG "STA %pM aid %d: PS buffer for AC %d\n",
470 		       sta->sta.addr, sta->sta.aid, ac);
471 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
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 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
477 			if (net_ratelimit())
478 				printk(KERN_DEBUG "%s: STA %pM TX buffer for "
479 				       "AC %d full - dropping oldest frame\n",
480 				       tx->sdata->name, sta->sta.addr, ac);
481 #endif
482 			dev_kfree_skb(old);
483 		} else
484 			tx->local->total_ps_buffered++;
485 
486 		info->control.jiffies = jiffies;
487 		info->control.vif = &tx->sdata->vif;
488 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
489 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
490 
491 		if (!timer_pending(&local->sta_cleanup))
492 			mod_timer(&local->sta_cleanup,
493 				  round_jiffies(jiffies +
494 						STA_INFO_CLEANUP_INTERVAL));
495 
496 		/*
497 		 * We queued up some frames, so the TIM bit might
498 		 * need to be set, recalculate it.
499 		 */
500 		sta_info_recalc_tim(sta);
501 
502 		return TX_QUEUED;
503 	}
504 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
505 	else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
506 		printk(KERN_DEBUG
507 		       "%s: STA %pM in PS mode, but polling/in SP -> send frame\n",
508 		       tx->sdata->name, sta->sta.addr);
509 	}
510 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
511 
512 	return TX_CONTINUE;
513 }
514 
515 static ieee80211_tx_result debug_noinline
516 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
517 {
518 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
519 		return TX_CONTINUE;
520 
521 	if (tx->flags & IEEE80211_TX_UNICAST)
522 		return ieee80211_tx_h_unicast_ps_buf(tx);
523 	else
524 		return ieee80211_tx_h_multicast_ps_buf(tx);
525 }
526 
527 static ieee80211_tx_result debug_noinline
528 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
529 {
530 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
531 
532 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
533 		     tx->sdata->control_port_no_encrypt))
534 		info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
535 
536 	return TX_CONTINUE;
537 }
538 
539 static ieee80211_tx_result debug_noinline
540 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
541 {
542 	struct ieee80211_key *key = NULL;
543 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
544 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
545 
546 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
547 		tx->key = NULL;
548 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
549 		tx->key = key;
550 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
551 		 is_multicast_ether_addr(hdr->addr1) &&
552 		 ieee80211_is_robust_mgmt_frame(hdr) &&
553 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
554 		tx->key = key;
555 	else if (is_multicast_ether_addr(hdr->addr1) &&
556 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
557 		tx->key = key;
558 	else if (!is_multicast_ether_addr(hdr->addr1) &&
559 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
560 		tx->key = key;
561 	else if (tx->sdata->drop_unencrypted &&
562 		 (tx->skb->protocol != tx->sdata->control_port_protocol) &&
563 		 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
564 		 (!ieee80211_is_robust_mgmt_frame(hdr) ||
565 		  (ieee80211_is_action(hdr->frame_control) &&
566 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))) {
567 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
568 		return TX_DROP;
569 	} else
570 		tx->key = NULL;
571 
572 	if (tx->key) {
573 		bool skip_hw = false;
574 
575 		tx->key->tx_rx_count++;
576 		/* TODO: add threshold stuff again */
577 
578 		switch (tx->key->conf.cipher) {
579 		case WLAN_CIPHER_SUITE_WEP40:
580 		case WLAN_CIPHER_SUITE_WEP104:
581 		case WLAN_CIPHER_SUITE_TKIP:
582 			if (!ieee80211_is_data_present(hdr->frame_control))
583 				tx->key = NULL;
584 			break;
585 		case WLAN_CIPHER_SUITE_CCMP:
586 			if (!ieee80211_is_data_present(hdr->frame_control) &&
587 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
588 					       tx->skb))
589 				tx->key = NULL;
590 			else
591 				skip_hw = (tx->key->conf.flags &
592 					   IEEE80211_KEY_FLAG_SW_MGMT) &&
593 					ieee80211_is_mgmt(hdr->frame_control);
594 			break;
595 		case WLAN_CIPHER_SUITE_AES_CMAC:
596 			if (!ieee80211_is_mgmt(hdr->frame_control))
597 				tx->key = NULL;
598 			break;
599 		}
600 
601 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED))
602 			return TX_DROP;
603 
604 		if (!skip_hw && tx->key &&
605 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
606 			info->control.hw_key = &tx->key->conf;
607 	}
608 
609 	return TX_CONTINUE;
610 }
611 
612 static ieee80211_tx_result debug_noinline
613 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
614 {
615 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
616 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
617 	struct ieee80211_supported_band *sband;
618 	struct ieee80211_rate *rate;
619 	int i;
620 	u32 len;
621 	bool inval = false, rts = false, short_preamble = false;
622 	struct ieee80211_tx_rate_control txrc;
623 	bool assoc = false;
624 
625 	memset(&txrc, 0, sizeof(txrc));
626 
627 	sband = tx->local->hw.wiphy->bands[tx->channel->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[tx->channel->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 	memcpy(txrc.rate_idx_mcs_mask,
644 	       tx->sdata->rc_rateidx_mcs_mask[tx->channel->band],
645 	       sizeof(txrc.rate_idx_mcs_mask));
646 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
647 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
648 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
649 
650 	/* set up RTS protection if desired */
651 	if (len > tx->local->hw.wiphy->rts_threshold) {
652 		txrc.rts = rts = true;
653 	}
654 
655 	/*
656 	 * Use short preamble if the BSS can handle it, but not for
657 	 * management frames unless we know the receiver can handle
658 	 * that -- the management frame might be to a station that
659 	 * just wants a probe response.
660 	 */
661 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
662 	    (ieee80211_is_data(hdr->frame_control) ||
663 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
664 		txrc.short_preamble = short_preamble = true;
665 
666 	if (tx->sta)
667 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
668 
669 	/*
670 	 * Lets not bother rate control if we're associated and cannot
671 	 * talk to the sta. This should not happen.
672 	 */
673 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
674 		 !rate_usable_index_exists(sband, &tx->sta->sta),
675 		 "%s: Dropped data frame as no usable bitrate found while "
676 		 "scanning and associated. Target station: "
677 		 "%pM on %d GHz band\n",
678 		 tx->sdata->name, hdr->addr1,
679 		 tx->channel->band ? 5 : 2))
680 		return TX_DROP;
681 
682 	/*
683 	 * If we're associated with the sta at this point we know we can at
684 	 * least send the frame at the lowest bit rate.
685 	 */
686 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
687 
688 	if (unlikely(info->control.rates[0].idx < 0))
689 		return TX_DROP;
690 
691 	if (txrc.reported_rate.idx < 0) {
692 		txrc.reported_rate = info->control.rates[0];
693 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
694 			tx->sta->last_tx_rate = txrc.reported_rate;
695 	} else if (tx->sta)
696 		tx->sta->last_tx_rate = txrc.reported_rate;
697 
698 	if (unlikely(!info->control.rates[0].count))
699 		info->control.rates[0].count = 1;
700 
701 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
702 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
703 		info->control.rates[0].count = 1;
704 
705 	if (is_multicast_ether_addr(hdr->addr1)) {
706 		/*
707 		 * XXX: verify the rate is in the basic rateset
708 		 */
709 		return TX_CONTINUE;
710 	}
711 
712 	/*
713 	 * set up the RTS/CTS rate as the fastest basic rate
714 	 * that is not faster than the data rate
715 	 *
716 	 * XXX: Should this check all retry rates?
717 	 */
718 	if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
719 		s8 baserate = 0;
720 
721 		rate = &sband->bitrates[info->control.rates[0].idx];
722 
723 		for (i = 0; i < sband->n_bitrates; i++) {
724 			/* must be a basic rate */
725 			if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
726 				continue;
727 			/* must not be faster than the data rate */
728 			if (sband->bitrates[i].bitrate > rate->bitrate)
729 				continue;
730 			/* maximum */
731 			if (sband->bitrates[baserate].bitrate <
732 			     sband->bitrates[i].bitrate)
733 				baserate = i;
734 		}
735 
736 		info->control.rts_cts_rate_idx = baserate;
737 	}
738 
739 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
740 		/*
741 		 * make sure there's no valid rate following
742 		 * an invalid one, just in case drivers don't
743 		 * take the API seriously to stop at -1.
744 		 */
745 		if (inval) {
746 			info->control.rates[i].idx = -1;
747 			continue;
748 		}
749 		if (info->control.rates[i].idx < 0) {
750 			inval = true;
751 			continue;
752 		}
753 
754 		/*
755 		 * For now assume MCS is already set up correctly, this
756 		 * needs to be fixed.
757 		 */
758 		if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
759 			WARN_ON(info->control.rates[i].idx > 76);
760 			continue;
761 		}
762 
763 		/* set up RTS protection if desired */
764 		if (rts)
765 			info->control.rates[i].flags |=
766 				IEEE80211_TX_RC_USE_RTS_CTS;
767 
768 		/* RC is busted */
769 		if (WARN_ON_ONCE(info->control.rates[i].idx >=
770 				 sband->n_bitrates)) {
771 			info->control.rates[i].idx = -1;
772 			continue;
773 		}
774 
775 		rate = &sband->bitrates[info->control.rates[i].idx];
776 
777 		/* set up short preamble */
778 		if (short_preamble &&
779 		    rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
780 			info->control.rates[i].flags |=
781 				IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
782 
783 		/* set up G protection */
784 		if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
785 		    rate->flags & IEEE80211_RATE_ERP_G)
786 			info->control.rates[i].flags |=
787 				IEEE80211_TX_RC_USE_CTS_PROTECT;
788 	}
789 
790 	return TX_CONTINUE;
791 }
792 
793 static ieee80211_tx_result debug_noinline
794 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
795 {
796 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
797 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
798 	u16 *seq;
799 	u8 *qc;
800 	int tid;
801 
802 	/*
803 	 * Packet injection may want to control the sequence
804 	 * number, if we have no matching interface then we
805 	 * neither assign one ourselves nor ask the driver to.
806 	 */
807 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
808 		return TX_CONTINUE;
809 
810 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
811 		return TX_CONTINUE;
812 
813 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
814 		return TX_CONTINUE;
815 
816 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
817 		return TX_CONTINUE;
818 
819 	/*
820 	 * Anything but QoS data that has a sequence number field
821 	 * (is long enough) gets a sequence number from the global
822 	 * counter.
823 	 */
824 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
825 		/* driver should assign sequence number */
826 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
827 		/* for pure STA mode without beacons, we can do it */
828 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
829 		tx->sdata->sequence_number += 0x10;
830 		return TX_CONTINUE;
831 	}
832 
833 	/*
834 	 * This should be true for injected/management frames only, for
835 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
836 	 * above since they are not QoS-data frames.
837 	 */
838 	if (!tx->sta)
839 		return TX_CONTINUE;
840 
841 	/* include per-STA, per-TID sequence counter */
842 
843 	qc = ieee80211_get_qos_ctl(hdr);
844 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
845 	seq = &tx->sta->tid_seq[tid];
846 
847 	hdr->seq_ctrl = cpu_to_le16(*seq);
848 
849 	/* Increase the sequence number. */
850 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
851 
852 	return TX_CONTINUE;
853 }
854 
855 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
856 			      struct sk_buff *skb, int hdrlen,
857 			      int frag_threshold)
858 {
859 	struct ieee80211_local *local = tx->local;
860 	struct ieee80211_tx_info *info;
861 	struct sk_buff *tmp;
862 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
863 	int pos = hdrlen + per_fragm;
864 	int rem = skb->len - hdrlen - per_fragm;
865 
866 	if (WARN_ON(rem < 0))
867 		return -EINVAL;
868 
869 	/* first fragment was already added to queue by caller */
870 
871 	while (rem) {
872 		int fraglen = per_fragm;
873 
874 		if (fraglen > rem)
875 			fraglen = rem;
876 		rem -= fraglen;
877 		tmp = dev_alloc_skb(local->tx_headroom +
878 				    frag_threshold +
879 				    IEEE80211_ENCRYPT_HEADROOM +
880 				    IEEE80211_ENCRYPT_TAILROOM);
881 		if (!tmp)
882 			return -ENOMEM;
883 
884 		__skb_queue_tail(&tx->skbs, tmp);
885 
886 		skb_reserve(tmp, local->tx_headroom +
887 				 IEEE80211_ENCRYPT_HEADROOM);
888 		/* copy control information */
889 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
890 
891 		info = IEEE80211_SKB_CB(tmp);
892 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
893 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
894 
895 		if (rem)
896 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
897 
898 		skb_copy_queue_mapping(tmp, skb);
899 		tmp->priority = skb->priority;
900 		tmp->dev = skb->dev;
901 
902 		/* copy header and data */
903 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
904 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
905 
906 		pos += fraglen;
907 	}
908 
909 	/* adjust first fragment's length */
910 	skb->len = hdrlen + per_fragm;
911 	return 0;
912 }
913 
914 static ieee80211_tx_result debug_noinline
915 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
916 {
917 	struct sk_buff *skb = tx->skb;
918 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
919 	struct ieee80211_hdr *hdr = (void *)skb->data;
920 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
921 	int hdrlen;
922 	int fragnum;
923 
924 	/* no matter what happens, tx->skb moves to tx->skbs */
925 	__skb_queue_tail(&tx->skbs, skb);
926 	tx->skb = NULL;
927 
928 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
929 		return TX_CONTINUE;
930 
931 	if (tx->local->ops->set_frag_threshold)
932 		return TX_CONTINUE;
933 
934 	/*
935 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
936 	 * This scenario is handled in ieee80211_tx_prepare but extra
937 	 * caution taken here as fragmented ampdu may cause Tx stop.
938 	 */
939 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
940 		return TX_DROP;
941 
942 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
943 
944 	/* internal error, why isn't DONTFRAG set? */
945 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
946 		return TX_DROP;
947 
948 	/*
949 	 * Now fragment the frame. This will allocate all the fragments and
950 	 * chain them (using skb as the first fragment) to skb->next.
951 	 * During transmission, we will remove the successfully transmitted
952 	 * fragments from this list. When the low-level driver rejects one
953 	 * of the fragments then we will simply pretend to accept the skb
954 	 * but store it away as pending.
955 	 */
956 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
957 		return TX_DROP;
958 
959 	/* update duration/seq/flags of fragments */
960 	fragnum = 0;
961 
962 	skb_queue_walk(&tx->skbs, skb) {
963 		int next_len;
964 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
965 
966 		hdr = (void *)skb->data;
967 		info = IEEE80211_SKB_CB(skb);
968 
969 		if (!skb_queue_is_last(&tx->skbs, skb)) {
970 			hdr->frame_control |= morefrags;
971 			/*
972 			 * No multi-rate retries for fragmented frames, that
973 			 * would completely throw off the NAV at other STAs.
974 			 */
975 			info->control.rates[1].idx = -1;
976 			info->control.rates[2].idx = -1;
977 			info->control.rates[3].idx = -1;
978 			info->control.rates[4].idx = -1;
979 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
980 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
981 		} else {
982 			hdr->frame_control &= ~morefrags;
983 			next_len = 0;
984 		}
985 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
986 		fragnum++;
987 	}
988 
989 	return TX_CONTINUE;
990 }
991 
992 static ieee80211_tx_result debug_noinline
993 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
994 {
995 	struct sk_buff *skb;
996 
997 	if (!tx->sta)
998 		return TX_CONTINUE;
999 
1000 	tx->sta->tx_packets++;
1001 	skb_queue_walk(&tx->skbs, skb) {
1002 		tx->sta->tx_fragments++;
1003 		tx->sta->tx_bytes += skb->len;
1004 	}
1005 
1006 	return TX_CONTINUE;
1007 }
1008 
1009 static ieee80211_tx_result debug_noinline
1010 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1011 {
1012 	if (!tx->key)
1013 		return TX_CONTINUE;
1014 
1015 	switch (tx->key->conf.cipher) {
1016 	case WLAN_CIPHER_SUITE_WEP40:
1017 	case WLAN_CIPHER_SUITE_WEP104:
1018 		return ieee80211_crypto_wep_encrypt(tx);
1019 	case WLAN_CIPHER_SUITE_TKIP:
1020 		return ieee80211_crypto_tkip_encrypt(tx);
1021 	case WLAN_CIPHER_SUITE_CCMP:
1022 		return ieee80211_crypto_ccmp_encrypt(tx);
1023 	case WLAN_CIPHER_SUITE_AES_CMAC:
1024 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1025 	default:
1026 		return ieee80211_crypto_hw_encrypt(tx);
1027 	}
1028 
1029 	return TX_DROP;
1030 }
1031 
1032 static ieee80211_tx_result debug_noinline
1033 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1034 {
1035 	struct sk_buff *skb;
1036 	struct ieee80211_hdr *hdr;
1037 	int next_len;
1038 	bool group_addr;
1039 
1040 	skb_queue_walk(&tx->skbs, skb) {
1041 		hdr = (void *) skb->data;
1042 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1043 			break; /* must not overwrite AID */
1044 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1045 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1046 			next_len = next->len;
1047 		} else
1048 			next_len = 0;
1049 		group_addr = is_multicast_ether_addr(hdr->addr1);
1050 
1051 		hdr->duration_id =
1052 			ieee80211_duration(tx, skb, group_addr, next_len);
1053 	}
1054 
1055 	return TX_CONTINUE;
1056 }
1057 
1058 /* actual transmit path */
1059 
1060 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1061 				  struct sk_buff *skb,
1062 				  struct ieee80211_tx_info *info,
1063 				  struct tid_ampdu_tx *tid_tx,
1064 				  int tid)
1065 {
1066 	bool queued = false;
1067 	bool reset_agg_timer = false;
1068 	struct sk_buff *purge_skb = NULL;
1069 
1070 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1071 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1072 		reset_agg_timer = true;
1073 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1074 		/*
1075 		 * nothing -- this aggregation session is being started
1076 		 * but that might still fail with the driver
1077 		 */
1078 	} else {
1079 		spin_lock(&tx->sta->lock);
1080 		/*
1081 		 * Need to re-check now, because we may get here
1082 		 *
1083 		 *  1) in the window during which the setup is actually
1084 		 *     already done, but not marked yet because not all
1085 		 *     packets are spliced over to the driver pending
1086 		 *     queue yet -- if this happened we acquire the lock
1087 		 *     either before or after the splice happens, but
1088 		 *     need to recheck which of these cases happened.
1089 		 *
1090 		 *  2) during session teardown, if the OPERATIONAL bit
1091 		 *     was cleared due to the teardown but the pointer
1092 		 *     hasn't been assigned NULL yet (or we loaded it
1093 		 *     before it was assigned) -- in this case it may
1094 		 *     now be NULL which means we should just let the
1095 		 *     packet pass through because splicing the frames
1096 		 *     back is already done.
1097 		 */
1098 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1099 
1100 		if (!tid_tx) {
1101 			/* do nothing, let packet pass through */
1102 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1103 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1104 			reset_agg_timer = true;
1105 		} else {
1106 			queued = true;
1107 			info->control.vif = &tx->sdata->vif;
1108 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1109 			__skb_queue_tail(&tid_tx->pending, skb);
1110 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1111 				purge_skb = __skb_dequeue(&tid_tx->pending);
1112 		}
1113 		spin_unlock(&tx->sta->lock);
1114 
1115 		if (purge_skb)
1116 			dev_kfree_skb(purge_skb);
1117 	}
1118 
1119 	/* reset session timer */
1120 	if (reset_agg_timer && tid_tx->timeout)
1121 		tid_tx->last_tx = jiffies;
1122 
1123 	return queued;
1124 }
1125 
1126 /*
1127  * initialises @tx
1128  */
1129 static ieee80211_tx_result
1130 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1131 		     struct ieee80211_tx_data *tx,
1132 		     struct sk_buff *skb)
1133 {
1134 	struct ieee80211_local *local = sdata->local;
1135 	struct ieee80211_hdr *hdr;
1136 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1137 	int tid;
1138 	u8 *qc;
1139 
1140 	memset(tx, 0, sizeof(*tx));
1141 	tx->skb = skb;
1142 	tx->local = local;
1143 	tx->sdata = sdata;
1144 	tx->channel = local->hw.conf.channel;
1145 	__skb_queue_head_init(&tx->skbs);
1146 
1147 	/*
1148 	 * If this flag is set to true anywhere, and we get here,
1149 	 * we are doing the needed processing, so remove the flag
1150 	 * now.
1151 	 */
1152 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1153 
1154 	hdr = (struct ieee80211_hdr *) skb->data;
1155 
1156 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1157 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1158 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1159 			return TX_DROP;
1160 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED) {
1161 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1162 	}
1163 	if (!tx->sta)
1164 		tx->sta = sta_info_get(sdata, hdr->addr1);
1165 
1166 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1167 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1168 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1169 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1170 		struct tid_ampdu_tx *tid_tx;
1171 
1172 		qc = ieee80211_get_qos_ctl(hdr);
1173 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1174 
1175 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1176 		if (tid_tx) {
1177 			bool queued;
1178 
1179 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1180 						       tid_tx, tid);
1181 
1182 			if (unlikely(queued))
1183 				return TX_QUEUED;
1184 		}
1185 	}
1186 
1187 	if (is_multicast_ether_addr(hdr->addr1)) {
1188 		tx->flags &= ~IEEE80211_TX_UNICAST;
1189 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1190 	} else
1191 		tx->flags |= IEEE80211_TX_UNICAST;
1192 
1193 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1194 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1195 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1196 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1197 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1198 	}
1199 
1200 	if (!tx->sta)
1201 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1202 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1203 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1204 
1205 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1206 
1207 	return TX_CONTINUE;
1208 }
1209 
1210 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1211 			       struct ieee80211_vif *vif,
1212 			       struct ieee80211_sta *sta,
1213 			       struct sk_buff_head *skbs,
1214 			       bool txpending)
1215 {
1216 	struct sk_buff *skb, *tmp;
1217 	struct ieee80211_tx_info *info;
1218 	unsigned long flags;
1219 
1220 	skb_queue_walk_safe(skbs, skb, tmp) {
1221 		int q = skb_get_queue_mapping(skb);
1222 
1223 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1224 		if (local->queue_stop_reasons[q] ||
1225 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1226 			/*
1227 			 * Since queue is stopped, queue up frames for later
1228 			 * transmission from the tx-pending tasklet when the
1229 			 * queue is woken again.
1230 			 */
1231 			if (txpending)
1232 				skb_queue_splice_init(skbs, &local->pending[q]);
1233 			else
1234 				skb_queue_splice_tail_init(skbs,
1235 							   &local->pending[q]);
1236 
1237 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1238 					       flags);
1239 			return false;
1240 		}
1241 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1242 
1243 		info = IEEE80211_SKB_CB(skb);
1244 		info->control.vif = vif;
1245 		info->control.sta = sta;
1246 
1247 		__skb_unlink(skb, skbs);
1248 		drv_tx(local, skb);
1249 	}
1250 
1251 	return true;
1252 }
1253 
1254 /*
1255  * Returns false if the frame couldn't be transmitted but was queued instead.
1256  */
1257 static bool __ieee80211_tx(struct ieee80211_local *local,
1258 			   struct sk_buff_head *skbs, int led_len,
1259 			   struct sta_info *sta, bool txpending)
1260 {
1261 	struct ieee80211_tx_info *info;
1262 	struct ieee80211_sub_if_data *sdata;
1263 	struct ieee80211_vif *vif;
1264 	struct ieee80211_sta *pubsta;
1265 	struct sk_buff *skb;
1266 	bool result = true;
1267 	__le16 fc;
1268 
1269 	if (WARN_ON(skb_queue_empty(skbs)))
1270 		return true;
1271 
1272 	skb = skb_peek(skbs);
1273 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1274 	info = IEEE80211_SKB_CB(skb);
1275 	sdata = vif_to_sdata(info->control.vif);
1276 	if (sta && !sta->uploaded)
1277 		sta = NULL;
1278 
1279 	if (sta)
1280 		pubsta = &sta->sta;
1281 	else
1282 		pubsta = NULL;
1283 
1284 	switch (sdata->vif.type) {
1285 	case NL80211_IFTYPE_MONITOR:
1286 		sdata = NULL;
1287 		vif = NULL;
1288 		break;
1289 	case NL80211_IFTYPE_AP_VLAN:
1290 		sdata = container_of(sdata->bss,
1291 				     struct ieee80211_sub_if_data, u.ap);
1292 		/* fall through */
1293 	default:
1294 		vif = &sdata->vif;
1295 		break;
1296 	}
1297 
1298 	if (local->ops->tx_frags)
1299 		drv_tx_frags(local, vif, pubsta, skbs);
1300 	else
1301 		result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1302 					    txpending);
1303 
1304 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1305 	ieee80211_led_tx(local, 1);
1306 
1307 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1308 
1309 	return result;
1310 }
1311 
1312 /*
1313  * Invoke TX handlers, return 0 on success and non-zero if the
1314  * frame was dropped or queued.
1315  */
1316 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1317 {
1318 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1319 	ieee80211_tx_result res = TX_DROP;
1320 
1321 #define CALL_TXH(txh) \
1322 	do {				\
1323 		res = txh(tx);		\
1324 		if (res != TX_CONTINUE)	\
1325 			goto txh_done;	\
1326 	} while (0)
1327 
1328 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1329 	CALL_TXH(ieee80211_tx_h_check_assoc);
1330 	CALL_TXH(ieee80211_tx_h_ps_buf);
1331 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1332 	CALL_TXH(ieee80211_tx_h_select_key);
1333 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1334 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1335 
1336 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1337 		__skb_queue_tail(&tx->skbs, tx->skb);
1338 		tx->skb = NULL;
1339 		goto txh_done;
1340 	}
1341 
1342 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1343 	CALL_TXH(ieee80211_tx_h_sequence);
1344 	CALL_TXH(ieee80211_tx_h_fragment);
1345 	/* handlers after fragment must be aware of tx info fragmentation! */
1346 	CALL_TXH(ieee80211_tx_h_stats);
1347 	CALL_TXH(ieee80211_tx_h_encrypt);
1348 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1349 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1350 #undef CALL_TXH
1351 
1352  txh_done:
1353 	if (unlikely(res == TX_DROP)) {
1354 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1355 		if (tx->skb)
1356 			dev_kfree_skb(tx->skb);
1357 		else
1358 			__skb_queue_purge(&tx->skbs);
1359 		return -1;
1360 	} else if (unlikely(res == TX_QUEUED)) {
1361 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1362 		return -1;
1363 	}
1364 
1365 	return 0;
1366 }
1367 
1368 /*
1369  * Returns false if the frame couldn't be transmitted but was queued instead.
1370  */
1371 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1372 			 struct sk_buff *skb, bool txpending)
1373 {
1374 	struct ieee80211_local *local = sdata->local;
1375 	struct ieee80211_tx_data tx;
1376 	ieee80211_tx_result res_prepare;
1377 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1378 	bool result = true;
1379 	int led_len;
1380 
1381 	if (unlikely(skb->len < 10)) {
1382 		dev_kfree_skb(skb);
1383 		return true;
1384 	}
1385 
1386 	rcu_read_lock();
1387 
1388 	/* initialises tx */
1389 	led_len = skb->len;
1390 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1391 
1392 	if (unlikely(res_prepare == TX_DROP)) {
1393 		dev_kfree_skb(skb);
1394 		goto out;
1395 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1396 		goto out;
1397 	}
1398 
1399 	tx.channel = local->hw.conf.channel;
1400 	info->band = tx.channel->band;
1401 
1402 	if (!invoke_tx_handlers(&tx))
1403 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1404 					tx.sta, txpending);
1405  out:
1406 	rcu_read_unlock();
1407 	return result;
1408 }
1409 
1410 /* device xmit handlers */
1411 
1412 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1413 				struct sk_buff *skb,
1414 				int head_need, bool may_encrypt)
1415 {
1416 	struct ieee80211_local *local = sdata->local;
1417 	int tail_need = 0;
1418 
1419 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1420 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1421 		tail_need -= skb_tailroom(skb);
1422 		tail_need = max_t(int, tail_need, 0);
1423 	}
1424 
1425 	if (skb_cloned(skb))
1426 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1427 	else if (head_need || tail_need)
1428 		I802_DEBUG_INC(local->tx_expand_skb_head);
1429 	else
1430 		return 0;
1431 
1432 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1433 		wiphy_debug(local->hw.wiphy,
1434 			    "failed to reallocate TX buffer\n");
1435 		return -ENOMEM;
1436 	}
1437 
1438 	return 0;
1439 }
1440 
1441 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
1442 {
1443 	struct ieee80211_local *local = sdata->local;
1444 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1445 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1446 	int headroom;
1447 	bool may_encrypt;
1448 
1449 	rcu_read_lock();
1450 
1451 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1452 
1453 	headroom = local->tx_headroom;
1454 	if (may_encrypt)
1455 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1456 	headroom -= skb_headroom(skb);
1457 	headroom = max_t(int, 0, headroom);
1458 
1459 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1460 		dev_kfree_skb(skb);
1461 		rcu_read_unlock();
1462 		return;
1463 	}
1464 
1465 	hdr = (struct ieee80211_hdr *) skb->data;
1466 	info->control.vif = &sdata->vif;
1467 
1468 	if (ieee80211_vif_is_mesh(&sdata->vif) &&
1469 	    ieee80211_is_data(hdr->frame_control) &&
1470 	    !is_multicast_ether_addr(hdr->addr1) &&
1471 	    mesh_nexthop_resolve(skb, sdata)) {
1472 		/* skb queued: don't free */
1473 		rcu_read_unlock();
1474 		return;
1475 	}
1476 
1477 	ieee80211_set_qos_hdr(sdata, skb);
1478 	ieee80211_tx(sdata, skb, false);
1479 	rcu_read_unlock();
1480 }
1481 
1482 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1483 {
1484 	struct ieee80211_radiotap_iterator iterator;
1485 	struct ieee80211_radiotap_header *rthdr =
1486 		(struct ieee80211_radiotap_header *) skb->data;
1487 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1488 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1489 						   NULL);
1490 	u16 txflags;
1491 
1492 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1493 		       IEEE80211_TX_CTL_DONTFRAG;
1494 
1495 	/*
1496 	 * for every radiotap entry that is present
1497 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1498 	 * entries present, or -EINVAL on error)
1499 	 */
1500 
1501 	while (!ret) {
1502 		ret = ieee80211_radiotap_iterator_next(&iterator);
1503 
1504 		if (ret)
1505 			continue;
1506 
1507 		/* see if this argument is something we can use */
1508 		switch (iterator.this_arg_index) {
1509 		/*
1510 		 * You must take care when dereferencing iterator.this_arg
1511 		 * for multibyte types... the pointer is not aligned.  Use
1512 		 * get_unaligned((type *)iterator.this_arg) to dereference
1513 		 * iterator.this_arg for type "type" safely on all arches.
1514 		*/
1515 		case IEEE80211_RADIOTAP_FLAGS:
1516 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1517 				/*
1518 				 * this indicates that the skb we have been
1519 				 * handed has the 32-bit FCS CRC at the end...
1520 				 * we should react to that by snipping it off
1521 				 * because it will be recomputed and added
1522 				 * on transmission
1523 				 */
1524 				if (skb->len < (iterator._max_length + FCS_LEN))
1525 					return false;
1526 
1527 				skb_trim(skb, skb->len - FCS_LEN);
1528 			}
1529 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1530 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1531 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1532 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1533 			break;
1534 
1535 		case IEEE80211_RADIOTAP_TX_FLAGS:
1536 			txflags = get_unaligned_le16(iterator.this_arg);
1537 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1538 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1539 			break;
1540 
1541 		/*
1542 		 * Please update the file
1543 		 * Documentation/networking/mac80211-injection.txt
1544 		 * when parsing new fields here.
1545 		 */
1546 
1547 		default:
1548 			break;
1549 		}
1550 	}
1551 
1552 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1553 		return false;
1554 
1555 	/*
1556 	 * remove the radiotap header
1557 	 * iterator->_max_length was sanity-checked against
1558 	 * skb->len by iterator init
1559 	 */
1560 	skb_pull(skb, iterator._max_length);
1561 
1562 	return true;
1563 }
1564 
1565 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1566 					 struct net_device *dev)
1567 {
1568 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1569 	struct ieee80211_channel *chan = local->hw.conf.channel;
1570 	struct ieee80211_radiotap_header *prthdr =
1571 		(struct ieee80211_radiotap_header *)skb->data;
1572 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1573 	struct ieee80211_hdr *hdr;
1574 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1575 	u16 len_rthdr;
1576 	int hdrlen;
1577 
1578 	/*
1579 	 * Frame injection is not allowed if beaconing is not allowed
1580 	 * or if we need radar detection. Beaconing is usually not allowed when
1581 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1582 	 * Passive scan is also used in world regulatory domains where
1583 	 * your country is not known and as such it should be treated as
1584 	 * NO TX unless the channel is explicitly allowed in which case
1585 	 * your current regulatory domain would not have the passive scan
1586 	 * flag.
1587 	 *
1588 	 * Since AP mode uses monitor interfaces to inject/TX management
1589 	 * frames we can make AP mode the exception to this rule once it
1590 	 * supports radar detection as its implementation can deal with
1591 	 * radar detection by itself. We can do that later by adding a
1592 	 * monitor flag interfaces used for AP support.
1593 	 */
1594 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1595 	     IEEE80211_CHAN_PASSIVE_SCAN)))
1596 		goto fail;
1597 
1598 	/* check for not even having the fixed radiotap header part */
1599 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1600 		goto fail; /* too short to be possibly valid */
1601 
1602 	/* is it a header version we can trust to find length from? */
1603 	if (unlikely(prthdr->it_version))
1604 		goto fail; /* only version 0 is supported */
1605 
1606 	/* then there must be a radiotap header with a length we can use */
1607 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1608 
1609 	/* does the skb contain enough to deliver on the alleged length? */
1610 	if (unlikely(skb->len < len_rthdr))
1611 		goto fail; /* skb too short for claimed rt header extent */
1612 
1613 	/*
1614 	 * fix up the pointers accounting for the radiotap
1615 	 * header still being in there.  We are being given
1616 	 * a precooked IEEE80211 header so no need for
1617 	 * normal processing
1618 	 */
1619 	skb_set_mac_header(skb, len_rthdr);
1620 	/*
1621 	 * these are just fixed to the end of the rt area since we
1622 	 * don't have any better information and at this point, nobody cares
1623 	 */
1624 	skb_set_network_header(skb, len_rthdr);
1625 	skb_set_transport_header(skb, len_rthdr);
1626 
1627 	if (skb->len < len_rthdr + 2)
1628 		goto fail;
1629 
1630 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1631 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1632 
1633 	if (skb->len < len_rthdr + hdrlen)
1634 		goto fail;
1635 
1636 	/*
1637 	 * Initialize skb->protocol if the injected frame is a data frame
1638 	 * carrying a rfc1042 header
1639 	 */
1640 	if (ieee80211_is_data(hdr->frame_control) &&
1641 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1642 		u8 *payload = (u8 *)hdr + hdrlen;
1643 
1644 		if (compare_ether_addr(payload, rfc1042_header) == 0)
1645 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1646 						    payload[7]);
1647 	}
1648 
1649 	memset(info, 0, sizeof(*info));
1650 
1651 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1652 		      IEEE80211_TX_CTL_INJECTED;
1653 
1654 	/* process and remove the injection radiotap header */
1655 	if (!ieee80211_parse_tx_radiotap(skb))
1656 		goto fail;
1657 
1658 	rcu_read_lock();
1659 
1660 	/*
1661 	 * We process outgoing injected frames that have a local address
1662 	 * we handle as though they are non-injected frames.
1663 	 * This code here isn't entirely correct, the local MAC address
1664 	 * isn't always enough to find the interface to use; for proper
1665 	 * VLAN/WDS support we will need a different mechanism (which
1666 	 * likely isn't going to be monitor interfaces).
1667 	 */
1668 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1669 
1670 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1671 		if (!ieee80211_sdata_running(tmp_sdata))
1672 			continue;
1673 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1674 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1675 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1676 			continue;
1677 		if (compare_ether_addr(tmp_sdata->vif.addr, hdr->addr2) == 0) {
1678 			sdata = tmp_sdata;
1679 			break;
1680 		}
1681 	}
1682 
1683 	ieee80211_xmit(sdata, skb);
1684 	rcu_read_unlock();
1685 
1686 	return NETDEV_TX_OK;
1687 
1688 fail:
1689 	dev_kfree_skb(skb);
1690 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1691 }
1692 
1693 /**
1694  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1695  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1696  * @skb: packet to be sent
1697  * @dev: incoming interface
1698  *
1699  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1700  * not be freed, and caller is responsible for either retrying later or freeing
1701  * skb).
1702  *
1703  * This function takes in an Ethernet header and encapsulates it with suitable
1704  * IEEE 802.11 header based on which interface the packet is coming in. The
1705  * encapsulated packet will then be passed to master interface, wlan#.11, for
1706  * transmission (through low-level driver).
1707  */
1708 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1709 				    struct net_device *dev)
1710 {
1711 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1712 	struct ieee80211_local *local = sdata->local;
1713 	struct ieee80211_tx_info *info;
1714 	int ret = NETDEV_TX_BUSY, head_need;
1715 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1716 	__le16 fc;
1717 	struct ieee80211_hdr hdr;
1718 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1719 	struct mesh_path __maybe_unused *mppath = NULL;
1720 	const u8 *encaps_data;
1721 	int encaps_len, skip_header_bytes;
1722 	int nh_pos, h_pos;
1723 	struct sta_info *sta = NULL;
1724 	bool wme_sta = false, authorized = false, tdls_auth = false;
1725 	bool tdls_direct = false;
1726 	bool multicast;
1727 	u32 info_flags = 0;
1728 	u16 info_id = 0;
1729 
1730 	if (unlikely(skb->len < ETH_HLEN)) {
1731 		ret = NETDEV_TX_OK;
1732 		goto fail;
1733 	}
1734 
1735 	/* convert Ethernet header to proper 802.11 header (based on
1736 	 * operation mode) */
1737 	ethertype = (skb->data[12] << 8) | skb->data[13];
1738 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1739 
1740 	switch (sdata->vif.type) {
1741 	case NL80211_IFTYPE_AP_VLAN:
1742 		rcu_read_lock();
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 		rcu_read_unlock();
1756 		if (sta)
1757 			break;
1758 		/* fall through */
1759 	case NL80211_IFTYPE_AP:
1760 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1761 		/* DA BSSID SA */
1762 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1763 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1764 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1765 		hdrlen = 24;
1766 		break;
1767 	case NL80211_IFTYPE_WDS:
1768 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1769 		/* RA TA DA SA */
1770 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1771 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1772 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1773 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1774 		hdrlen = 30;
1775 		break;
1776 #ifdef CONFIG_MAC80211_MESH
1777 	case NL80211_IFTYPE_MESH_POINT:
1778 		if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1779 			/* Do not send frames with mesh_ttl == 0 */
1780 			sdata->u.mesh.mshstats.dropped_frames_ttl++;
1781 			ret = NETDEV_TX_OK;
1782 			goto fail;
1783 		}
1784 		rcu_read_lock();
1785 		if (!is_multicast_ether_addr(skb->data))
1786 			mppath = mpp_path_lookup(skb->data, sdata);
1787 
1788 		/*
1789 		 * Use address extension if it is a packet from
1790 		 * another interface or if we know the destination
1791 		 * is being proxied by a portal (i.e. portal address
1792 		 * differs from proxied address)
1793 		 */
1794 		if (compare_ether_addr(sdata->vif.addr,
1795 				       skb->data + ETH_ALEN) == 0 &&
1796 		    !(mppath && compare_ether_addr(mppath->mpp, skb->data))) {
1797 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1798 					skb->data, skb->data + ETH_ALEN);
1799 			rcu_read_unlock();
1800 			meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
1801 					sdata, NULL, NULL);
1802 		} else {
1803 			int is_mesh_mcast = 1;
1804 			const u8 *mesh_da;
1805 
1806 			if (is_multicast_ether_addr(skb->data))
1807 				/* DA TA mSA AE:SA */
1808 				mesh_da = skb->data;
1809 			else {
1810 				static const u8 bcast[ETH_ALEN] =
1811 					{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
1812 				if (mppath) {
1813 					/* RA TA mDA mSA AE:DA SA */
1814 					mesh_da = mppath->mpp;
1815 					is_mesh_mcast = 0;
1816 				} else {
1817 					/* DA TA mSA AE:SA */
1818 					mesh_da = bcast;
1819 				}
1820 			}
1821 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1822 					mesh_da, sdata->vif.addr);
1823 			rcu_read_unlock();
1824 			if (is_mesh_mcast)
1825 				meshhdrlen =
1826 					ieee80211_new_mesh_header(&mesh_hdr,
1827 							sdata,
1828 							skb->data + ETH_ALEN,
1829 							NULL);
1830 			else
1831 				meshhdrlen =
1832 					ieee80211_new_mesh_header(&mesh_hdr,
1833 							sdata,
1834 							skb->data,
1835 							skb->data + ETH_ALEN);
1836 
1837 		}
1838 		break;
1839 #endif
1840 	case NL80211_IFTYPE_STATION:
1841 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1842 			bool tdls_peer = false;
1843 
1844 			rcu_read_lock();
1845 			sta = sta_info_get(sdata, skb->data);
1846 			if (sta) {
1847 				authorized = test_sta_flag(sta,
1848 							WLAN_STA_AUTHORIZED);
1849 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1850 				tdls_peer = test_sta_flag(sta,
1851 							 WLAN_STA_TDLS_PEER);
1852 				tdls_auth = test_sta_flag(sta,
1853 						WLAN_STA_TDLS_PEER_AUTH);
1854 			}
1855 			rcu_read_unlock();
1856 
1857 			/*
1858 			 * If the TDLS link is enabled, send everything
1859 			 * directly. Otherwise, allow TDLS setup frames
1860 			 * to be transmitted indirectly.
1861 			 */
1862 			tdls_direct = tdls_peer && (tdls_auth ||
1863 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1864 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1865 		}
1866 
1867 		if (tdls_direct) {
1868 			/* link during setup - throw out frames to peer */
1869 			if (!tdls_auth) {
1870 				ret = NETDEV_TX_OK;
1871 				goto fail;
1872 			}
1873 
1874 			/* DA SA BSSID */
1875 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1876 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1877 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1878 			hdrlen = 24;
1879 		}  else if (sdata->u.mgd.use_4addr &&
1880 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1881 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1882 					  IEEE80211_FCTL_TODS);
1883 			/* RA TA DA SA */
1884 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1885 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1886 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1887 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1888 			hdrlen = 30;
1889 		} else {
1890 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1891 			/* BSSID SA DA */
1892 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1893 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1894 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1895 			hdrlen = 24;
1896 		}
1897 		break;
1898 	case NL80211_IFTYPE_ADHOC:
1899 		/* DA SA BSSID */
1900 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1901 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1902 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1903 		hdrlen = 24;
1904 		break;
1905 	default:
1906 		ret = NETDEV_TX_OK;
1907 		goto fail;
1908 	}
1909 
1910 	/*
1911 	 * There's no need to try to look up the destination
1912 	 * if it is a multicast address (which can only happen
1913 	 * in AP mode)
1914 	 */
1915 	multicast = is_multicast_ether_addr(hdr.addr1);
1916 	if (!multicast) {
1917 		rcu_read_lock();
1918 		sta = sta_info_get(sdata, hdr.addr1);
1919 		if (sta) {
1920 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1921 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1922 		}
1923 		rcu_read_unlock();
1924 	}
1925 
1926 	/* For mesh, the use of the QoS header is mandatory */
1927 	if (ieee80211_vif_is_mesh(&sdata->vif))
1928 		wme_sta = true;
1929 
1930 	/* receiver and we are QoS enabled, use a QoS type frame */
1931 	if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
1932 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1933 		hdrlen += 2;
1934 	}
1935 
1936 	/*
1937 	 * Drop unicast frames to unauthorised stations unless they are
1938 	 * EAPOL frames from the local station.
1939 	 */
1940 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
1941 		     !is_multicast_ether_addr(hdr.addr1) && !authorized &&
1942 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
1943 		      compare_ether_addr(sdata->vif.addr, skb->data + ETH_ALEN)))) {
1944 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1945 		if (net_ratelimit())
1946 			printk(KERN_DEBUG "%s: dropped frame to %pM"
1947 			       " (unauthorized port)\n", dev->name,
1948 			       hdr.addr1);
1949 #endif
1950 
1951 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1952 
1953 		ret = NETDEV_TX_OK;
1954 		goto fail;
1955 	}
1956 
1957 	if (unlikely(!multicast && skb->sk &&
1958 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
1959 		struct sk_buff *orig_skb = skb;
1960 
1961 		skb = skb_clone(skb, GFP_ATOMIC);
1962 		if (skb) {
1963 			unsigned long flags;
1964 			int id, r;
1965 
1966 			spin_lock_irqsave(&local->ack_status_lock, flags);
1967 			r = idr_get_new_above(&local->ack_status_frames,
1968 					      orig_skb, 1, &id);
1969 			if (r == -EAGAIN) {
1970 				idr_pre_get(&local->ack_status_frames,
1971 					    GFP_ATOMIC);
1972 				r = idr_get_new_above(&local->ack_status_frames,
1973 						      orig_skb, 1, &id);
1974 			}
1975 			if (WARN_ON(!id) || id > 0xffff) {
1976 				idr_remove(&local->ack_status_frames, id);
1977 				r = -ERANGE;
1978 			}
1979 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
1980 
1981 			if (!r) {
1982 				info_id = id;
1983 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1984 			} else if (skb_shared(skb)) {
1985 				kfree_skb(orig_skb);
1986 			} else {
1987 				kfree_skb(skb);
1988 				skb = orig_skb;
1989 			}
1990 		} else {
1991 			/* couldn't clone -- lose tx status ... */
1992 			skb = orig_skb;
1993 		}
1994 	}
1995 
1996 	/*
1997 	 * If the skb is shared we need to obtain our own copy.
1998 	 */
1999 	if (skb_shared(skb)) {
2000 		struct sk_buff *tmp_skb = skb;
2001 
2002 		/* can't happen -- skb is a clone if info_id != 0 */
2003 		WARN_ON(info_id);
2004 
2005 		skb = skb_clone(skb, GFP_ATOMIC);
2006 		kfree_skb(tmp_skb);
2007 
2008 		if (!skb) {
2009 			ret = NETDEV_TX_OK;
2010 			goto fail;
2011 		}
2012 	}
2013 
2014 	hdr.frame_control = fc;
2015 	hdr.duration_id = 0;
2016 	hdr.seq_ctrl = 0;
2017 
2018 	skip_header_bytes = ETH_HLEN;
2019 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2020 		encaps_data = bridge_tunnel_header;
2021 		encaps_len = sizeof(bridge_tunnel_header);
2022 		skip_header_bytes -= 2;
2023 	} else if (ethertype >= 0x600) {
2024 		encaps_data = rfc1042_header;
2025 		encaps_len = sizeof(rfc1042_header);
2026 		skip_header_bytes -= 2;
2027 	} else {
2028 		encaps_data = NULL;
2029 		encaps_len = 0;
2030 	}
2031 
2032 	nh_pos = skb_network_header(skb) - skb->data;
2033 	h_pos = skb_transport_header(skb) - skb->data;
2034 
2035 	skb_pull(skb, skip_header_bytes);
2036 	nh_pos -= skip_header_bytes;
2037 	h_pos -= skip_header_bytes;
2038 
2039 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2040 
2041 	/*
2042 	 * So we need to modify the skb header and hence need a copy of
2043 	 * that. The head_need variable above doesn't, so far, include
2044 	 * the needed header space that we don't need right away. If we
2045 	 * can, then we don't reallocate right now but only after the
2046 	 * frame arrives at the master device (if it does...)
2047 	 *
2048 	 * If we cannot, however, then we will reallocate to include all
2049 	 * the ever needed space. Also, if we need to reallocate it anyway,
2050 	 * make it big enough for everything we may ever need.
2051 	 */
2052 
2053 	if (head_need > 0 || skb_cloned(skb)) {
2054 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2055 		head_need += local->tx_headroom;
2056 		head_need = max_t(int, 0, head_need);
2057 		if (ieee80211_skb_resize(sdata, skb, head_need, true))
2058 			goto fail;
2059 	}
2060 
2061 	if (encaps_data) {
2062 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2063 		nh_pos += encaps_len;
2064 		h_pos += encaps_len;
2065 	}
2066 
2067 #ifdef CONFIG_MAC80211_MESH
2068 	if (meshhdrlen > 0) {
2069 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2070 		nh_pos += meshhdrlen;
2071 		h_pos += meshhdrlen;
2072 	}
2073 #endif
2074 
2075 	if (ieee80211_is_data_qos(fc)) {
2076 		__le16 *qos_control;
2077 
2078 		qos_control = (__le16*) skb_push(skb, 2);
2079 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2080 		/*
2081 		 * Maybe we could actually set some fields here, for now just
2082 		 * initialise to zero to indicate no special operation.
2083 		 */
2084 		*qos_control = 0;
2085 	} else
2086 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2087 
2088 	nh_pos += hdrlen;
2089 	h_pos += hdrlen;
2090 
2091 	dev->stats.tx_packets++;
2092 	dev->stats.tx_bytes += skb->len;
2093 
2094 	/* Update skb pointers to various headers since this modified frame
2095 	 * is going to go through Linux networking code that may potentially
2096 	 * need things like pointer to IP header. */
2097 	skb_set_mac_header(skb, 0);
2098 	skb_set_network_header(skb, nh_pos);
2099 	skb_set_transport_header(skb, h_pos);
2100 
2101 	info = IEEE80211_SKB_CB(skb);
2102 	memset(info, 0, sizeof(*info));
2103 
2104 	dev->trans_start = jiffies;
2105 
2106 	info->flags = info_flags;
2107 	info->ack_frame_id = info_id;
2108 
2109 	ieee80211_xmit(sdata, skb);
2110 
2111 	return NETDEV_TX_OK;
2112 
2113  fail:
2114 	if (ret == NETDEV_TX_OK)
2115 		dev_kfree_skb(skb);
2116 
2117 	return ret;
2118 }
2119 
2120 
2121 /*
2122  * ieee80211_clear_tx_pending may not be called in a context where
2123  * it is possible that it packets could come in again.
2124  */
2125 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2126 {
2127 	int i;
2128 
2129 	for (i = 0; i < local->hw.queues; i++)
2130 		skb_queue_purge(&local->pending[i]);
2131 }
2132 
2133 /*
2134  * Returns false if the frame couldn't be transmitted but was queued instead,
2135  * which in this case means re-queued -- take as an indication to stop sending
2136  * more pending frames.
2137  */
2138 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2139 				     struct sk_buff *skb)
2140 {
2141 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2142 	struct ieee80211_sub_if_data *sdata;
2143 	struct sta_info *sta;
2144 	struct ieee80211_hdr *hdr;
2145 	bool result;
2146 
2147 	sdata = vif_to_sdata(info->control.vif);
2148 
2149 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2150 		result = ieee80211_tx(sdata, skb, true);
2151 	} else {
2152 		struct sk_buff_head skbs;
2153 
2154 		__skb_queue_head_init(&skbs);
2155 		__skb_queue_tail(&skbs, skb);
2156 
2157 		hdr = (struct ieee80211_hdr *)skb->data;
2158 		sta = sta_info_get(sdata, hdr->addr1);
2159 
2160 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2161 	}
2162 
2163 	return result;
2164 }
2165 
2166 /*
2167  * Transmit all pending packets. Called from tasklet.
2168  */
2169 void ieee80211_tx_pending(unsigned long data)
2170 {
2171 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2172 	struct ieee80211_sub_if_data *sdata;
2173 	unsigned long flags;
2174 	int i;
2175 	bool txok;
2176 
2177 	rcu_read_lock();
2178 
2179 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2180 	for (i = 0; i < local->hw.queues; i++) {
2181 		/*
2182 		 * If queue is stopped by something other than due to pending
2183 		 * frames, or we have no pending frames, proceed to next queue.
2184 		 */
2185 		if (local->queue_stop_reasons[i] ||
2186 		    skb_queue_empty(&local->pending[i]))
2187 			continue;
2188 
2189 		while (!skb_queue_empty(&local->pending[i])) {
2190 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2191 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2192 
2193 			if (WARN_ON(!info->control.vif)) {
2194 				kfree_skb(skb);
2195 				continue;
2196 			}
2197 
2198 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2199 						flags);
2200 
2201 			txok = ieee80211_tx_pending_skb(local, skb);
2202 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2203 					  flags);
2204 			if (!txok)
2205 				break;
2206 		}
2207 
2208 		if (skb_queue_empty(&local->pending[i]))
2209 			list_for_each_entry_rcu(sdata, &local->interfaces, list)
2210 				netif_wake_subqueue(sdata->dev, i);
2211 	}
2212 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2213 
2214 	rcu_read_unlock();
2215 }
2216 
2217 /* functions for drivers to get certain frames */
2218 
2219 static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2220 				     struct ieee80211_if_ap *bss,
2221 				     struct sk_buff *skb,
2222 				     struct beacon_data *beacon)
2223 {
2224 	u8 *pos, *tim;
2225 	int aid0 = 0;
2226 	int i, have_bits = 0, n1, n2;
2227 
2228 	/* Generate bitmap for TIM only if there are any STAs in power save
2229 	 * mode. */
2230 	if (atomic_read(&bss->num_sta_ps) > 0)
2231 		/* in the hope that this is faster than
2232 		 * checking byte-for-byte */
2233 		have_bits = !bitmap_empty((unsigned long*)bss->tim,
2234 					  IEEE80211_MAX_AID+1);
2235 
2236 	if (bss->dtim_count == 0)
2237 		bss->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
2238 	else
2239 		bss->dtim_count--;
2240 
2241 	tim = pos = (u8 *) skb_put(skb, 6);
2242 	*pos++ = WLAN_EID_TIM;
2243 	*pos++ = 4;
2244 	*pos++ = bss->dtim_count;
2245 	*pos++ = sdata->vif.bss_conf.dtim_period;
2246 
2247 	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
2248 		aid0 = 1;
2249 
2250 	bss->dtim_bc_mc = aid0 == 1;
2251 
2252 	if (have_bits) {
2253 		/* Find largest even number N1 so that bits numbered 1 through
2254 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2255 		 * (N2 + 1) x 8 through 2007 are 0. */
2256 		n1 = 0;
2257 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2258 			if (bss->tim[i]) {
2259 				n1 = i & 0xfe;
2260 				break;
2261 			}
2262 		}
2263 		n2 = n1;
2264 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2265 			if (bss->tim[i]) {
2266 				n2 = i;
2267 				break;
2268 			}
2269 		}
2270 
2271 		/* Bitmap control */
2272 		*pos++ = n1 | aid0;
2273 		/* Part Virt Bitmap */
2274 		skb_put(skb, n2 - n1);
2275 		memcpy(pos, bss->tim + n1, n2 - n1 + 1);
2276 
2277 		tim[1] = n2 - n1 + 4;
2278 	} else {
2279 		*pos++ = aid0; /* Bitmap control */
2280 		*pos++ = 0; /* Part Virt Bitmap */
2281 	}
2282 }
2283 
2284 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2285 					 struct ieee80211_vif *vif,
2286 					 u16 *tim_offset, u16 *tim_length)
2287 {
2288 	struct ieee80211_local *local = hw_to_local(hw);
2289 	struct sk_buff *skb = NULL;
2290 	struct ieee80211_tx_info *info;
2291 	struct ieee80211_sub_if_data *sdata = NULL;
2292 	struct ieee80211_if_ap *ap = NULL;
2293 	struct beacon_data *beacon;
2294 	struct ieee80211_supported_band *sband;
2295 	enum ieee80211_band band = local->hw.conf.channel->band;
2296 	struct ieee80211_tx_rate_control txrc;
2297 
2298 	sband = local->hw.wiphy->bands[band];
2299 
2300 	rcu_read_lock();
2301 
2302 	sdata = vif_to_sdata(vif);
2303 
2304 	if (!ieee80211_sdata_running(sdata))
2305 		goto out;
2306 
2307 	if (tim_offset)
2308 		*tim_offset = 0;
2309 	if (tim_length)
2310 		*tim_length = 0;
2311 
2312 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2313 		ap = &sdata->u.ap;
2314 		beacon = rcu_dereference(ap->beacon);
2315 		if (beacon) {
2316 			/*
2317 			 * headroom, head length,
2318 			 * tail length and maximum TIM length
2319 			 */
2320 			skb = dev_alloc_skb(local->tx_headroom +
2321 					    beacon->head_len +
2322 					    beacon->tail_len + 256);
2323 			if (!skb)
2324 				goto out;
2325 
2326 			skb_reserve(skb, local->tx_headroom);
2327 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2328 			       beacon->head_len);
2329 
2330 			/*
2331 			 * Not very nice, but we want to allow the driver to call
2332 			 * ieee80211_beacon_get() as a response to the set_tim()
2333 			 * callback. That, however, is already invoked under the
2334 			 * sta_lock to guarantee consistent and race-free update
2335 			 * of the tim bitmap in mac80211 and the driver.
2336 			 */
2337 			if (local->tim_in_locked_section) {
2338 				ieee80211_beacon_add_tim(sdata, ap, skb,
2339 							 beacon);
2340 			} else {
2341 				unsigned long flags;
2342 
2343 				spin_lock_irqsave(&local->tim_lock, flags);
2344 				ieee80211_beacon_add_tim(sdata, ap, skb,
2345 							 beacon);
2346 				spin_unlock_irqrestore(&local->tim_lock, flags);
2347 			}
2348 
2349 			if (tim_offset)
2350 				*tim_offset = beacon->head_len;
2351 			if (tim_length)
2352 				*tim_length = skb->len - beacon->head_len;
2353 
2354 			if (beacon->tail)
2355 				memcpy(skb_put(skb, beacon->tail_len),
2356 				       beacon->tail, beacon->tail_len);
2357 		} else
2358 			goto out;
2359 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2360 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2361 		struct ieee80211_hdr *hdr;
2362 		struct sk_buff *presp = rcu_dereference(ifibss->presp);
2363 
2364 		if (!presp)
2365 			goto out;
2366 
2367 		skb = skb_copy(presp, GFP_ATOMIC);
2368 		if (!skb)
2369 			goto out;
2370 
2371 		hdr = (struct ieee80211_hdr *) skb->data;
2372 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2373 						 IEEE80211_STYPE_BEACON);
2374 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2375 		struct ieee80211_mgmt *mgmt;
2376 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2377 		u8 *pos;
2378 		int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
2379 			      sizeof(mgmt->u.beacon);
2380 
2381 #ifdef CONFIG_MAC80211_MESH
2382 		if (!sdata->u.mesh.mesh_id_len)
2383 			goto out;
2384 #endif
2385 
2386 		if (ifmsh->sync_ops)
2387 			ifmsh->sync_ops->adjust_tbtt(
2388 						sdata);
2389 
2390 		skb = dev_alloc_skb(local->tx_headroom +
2391 				    hdr_len +
2392 				    2 + /* NULL SSID */
2393 				    2 + 8 + /* supported rates */
2394 				    2 + 3 + /* DS params */
2395 				    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2396 				    2 + sizeof(struct ieee80211_ht_cap) +
2397 				    2 + sizeof(struct ieee80211_ht_operation) +
2398 				    2 + sdata->u.mesh.mesh_id_len +
2399 				    2 + sizeof(struct ieee80211_meshconf_ie) +
2400 				    sdata->u.mesh.ie_len);
2401 		if (!skb)
2402 			goto out;
2403 
2404 		skb_reserve(skb, local->hw.extra_tx_headroom);
2405 		mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
2406 		memset(mgmt, 0, hdr_len);
2407 		mgmt->frame_control =
2408 		    cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2409 		memset(mgmt->da, 0xff, ETH_ALEN);
2410 		memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
2411 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
2412 		mgmt->u.beacon.beacon_int =
2413 			cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2414 		mgmt->u.beacon.capab_info |= cpu_to_le16(
2415 			sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
2416 
2417 		pos = skb_put(skb, 2);
2418 		*pos++ = WLAN_EID_SSID;
2419 		*pos++ = 0x0;
2420 
2421 		if (ieee80211_add_srates_ie(&sdata->vif, skb) ||
2422 		    mesh_add_ds_params_ie(skb, sdata) ||
2423 		    ieee80211_add_ext_srates_ie(&sdata->vif, skb) ||
2424 		    mesh_add_rsn_ie(skb, sdata) ||
2425 		    mesh_add_ht_cap_ie(skb, sdata) ||
2426 		    mesh_add_ht_oper_ie(skb, sdata) ||
2427 		    mesh_add_meshid_ie(skb, sdata) ||
2428 		    mesh_add_meshconf_ie(skb, sdata) ||
2429 		    mesh_add_vendor_ies(skb, sdata)) {
2430 			pr_err("o11s: couldn't add ies!\n");
2431 			goto out;
2432 		}
2433 	} else {
2434 		WARN_ON(1);
2435 		goto out;
2436 	}
2437 
2438 	info = IEEE80211_SKB_CB(skb);
2439 
2440 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2441 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2442 	info->band = band;
2443 
2444 	memset(&txrc, 0, sizeof(txrc));
2445 	txrc.hw = hw;
2446 	txrc.sband = sband;
2447 	txrc.bss_conf = &sdata->vif.bss_conf;
2448 	txrc.skb = skb;
2449 	txrc.reported_rate.idx = -1;
2450 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2451 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
2452 		txrc.max_rate_idx = -1;
2453 	else
2454 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2455 	memcpy(txrc.rate_idx_mcs_mask, sdata->rc_rateidx_mcs_mask[band],
2456 	       sizeof(txrc.rate_idx_mcs_mask));
2457 	txrc.bss = true;
2458 	rate_control_get_rate(sdata, NULL, &txrc);
2459 
2460 	info->control.vif = vif;
2461 
2462 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2463 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2464 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2465  out:
2466 	rcu_read_unlock();
2467 	return skb;
2468 }
2469 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2470 
2471 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
2472 					struct ieee80211_vif *vif)
2473 {
2474 	struct ieee80211_if_ap *ap = NULL;
2475 	struct sk_buff *presp = NULL, *skb = NULL;
2476 	struct ieee80211_hdr *hdr;
2477 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2478 
2479 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2480 		return NULL;
2481 
2482 	rcu_read_lock();
2483 
2484 	ap = &sdata->u.ap;
2485 	presp = rcu_dereference(ap->probe_resp);
2486 	if (!presp)
2487 		goto out;
2488 
2489 	skb = skb_copy(presp, GFP_ATOMIC);
2490 	if (!skb)
2491 		goto out;
2492 
2493 	hdr = (struct ieee80211_hdr *) skb->data;
2494 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2495 
2496 out:
2497 	rcu_read_unlock();
2498 	return skb;
2499 }
2500 EXPORT_SYMBOL(ieee80211_proberesp_get);
2501 
2502 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2503 				     struct ieee80211_vif *vif)
2504 {
2505 	struct ieee80211_sub_if_data *sdata;
2506 	struct ieee80211_if_managed *ifmgd;
2507 	struct ieee80211_pspoll *pspoll;
2508 	struct ieee80211_local *local;
2509 	struct sk_buff *skb;
2510 
2511 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2512 		return NULL;
2513 
2514 	sdata = vif_to_sdata(vif);
2515 	ifmgd = &sdata->u.mgd;
2516 	local = sdata->local;
2517 
2518 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2519 	if (!skb)
2520 		return NULL;
2521 
2522 	skb_reserve(skb, local->hw.extra_tx_headroom);
2523 
2524 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2525 	memset(pspoll, 0, sizeof(*pspoll));
2526 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2527 					    IEEE80211_STYPE_PSPOLL);
2528 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2529 
2530 	/* aid in PS-Poll has its two MSBs each set to 1 */
2531 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2532 
2533 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2534 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2535 
2536 	return skb;
2537 }
2538 EXPORT_SYMBOL(ieee80211_pspoll_get);
2539 
2540 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2541 				       struct ieee80211_vif *vif)
2542 {
2543 	struct ieee80211_hdr_3addr *nullfunc;
2544 	struct ieee80211_sub_if_data *sdata;
2545 	struct ieee80211_if_managed *ifmgd;
2546 	struct ieee80211_local *local;
2547 	struct sk_buff *skb;
2548 
2549 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2550 		return NULL;
2551 
2552 	sdata = vif_to_sdata(vif);
2553 	ifmgd = &sdata->u.mgd;
2554 	local = sdata->local;
2555 
2556 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2557 	if (!skb)
2558 		return NULL;
2559 
2560 	skb_reserve(skb, local->hw.extra_tx_headroom);
2561 
2562 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2563 							  sizeof(*nullfunc));
2564 	memset(nullfunc, 0, sizeof(*nullfunc));
2565 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2566 					      IEEE80211_STYPE_NULLFUNC |
2567 					      IEEE80211_FCTL_TODS);
2568 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2569 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2570 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2571 
2572 	return skb;
2573 }
2574 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2575 
2576 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2577 				       struct ieee80211_vif *vif,
2578 				       const u8 *ssid, size_t ssid_len,
2579 				       const u8 *ie, size_t ie_len)
2580 {
2581 	struct ieee80211_sub_if_data *sdata;
2582 	struct ieee80211_local *local;
2583 	struct ieee80211_hdr_3addr *hdr;
2584 	struct sk_buff *skb;
2585 	size_t ie_ssid_len;
2586 	u8 *pos;
2587 
2588 	sdata = vif_to_sdata(vif);
2589 	local = sdata->local;
2590 	ie_ssid_len = 2 + ssid_len;
2591 
2592 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2593 			    ie_ssid_len + ie_len);
2594 	if (!skb)
2595 		return NULL;
2596 
2597 	skb_reserve(skb, local->hw.extra_tx_headroom);
2598 
2599 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2600 	memset(hdr, 0, sizeof(*hdr));
2601 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2602 					 IEEE80211_STYPE_PROBE_REQ);
2603 	memset(hdr->addr1, 0xff, ETH_ALEN);
2604 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2605 	memset(hdr->addr3, 0xff, ETH_ALEN);
2606 
2607 	pos = skb_put(skb, ie_ssid_len);
2608 	*pos++ = WLAN_EID_SSID;
2609 	*pos++ = ssid_len;
2610 	if (ssid_len)
2611 		memcpy(pos, ssid, ssid_len);
2612 	pos += ssid_len;
2613 
2614 	if (ie) {
2615 		pos = skb_put(skb, ie_len);
2616 		memcpy(pos, ie, ie_len);
2617 	}
2618 
2619 	return skb;
2620 }
2621 EXPORT_SYMBOL(ieee80211_probereq_get);
2622 
2623 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2624 		       const void *frame, size_t frame_len,
2625 		       const struct ieee80211_tx_info *frame_txctl,
2626 		       struct ieee80211_rts *rts)
2627 {
2628 	const struct ieee80211_hdr *hdr = frame;
2629 
2630 	rts->frame_control =
2631 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2632 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2633 					       frame_txctl);
2634 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2635 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2636 }
2637 EXPORT_SYMBOL(ieee80211_rts_get);
2638 
2639 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2640 			     const void *frame, size_t frame_len,
2641 			     const struct ieee80211_tx_info *frame_txctl,
2642 			     struct ieee80211_cts *cts)
2643 {
2644 	const struct ieee80211_hdr *hdr = frame;
2645 
2646 	cts->frame_control =
2647 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2648 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2649 						     frame_len, frame_txctl);
2650 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2651 }
2652 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2653 
2654 struct sk_buff *
2655 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2656 			  struct ieee80211_vif *vif)
2657 {
2658 	struct ieee80211_local *local = hw_to_local(hw);
2659 	struct sk_buff *skb = NULL;
2660 	struct ieee80211_tx_data tx;
2661 	struct ieee80211_sub_if_data *sdata;
2662 	struct ieee80211_if_ap *bss = NULL;
2663 	struct beacon_data *beacon;
2664 	struct ieee80211_tx_info *info;
2665 
2666 	sdata = vif_to_sdata(vif);
2667 	bss = &sdata->u.ap;
2668 
2669 	rcu_read_lock();
2670 	beacon = rcu_dereference(bss->beacon);
2671 
2672 	if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2673 		goto out;
2674 
2675 	if (bss->dtim_count != 0 || !bss->dtim_bc_mc)
2676 		goto out; /* send buffered bc/mc only after DTIM beacon */
2677 
2678 	while (1) {
2679 		skb = skb_dequeue(&bss->ps_bc_buf);
2680 		if (!skb)
2681 			goto out;
2682 		local->total_ps_buffered--;
2683 
2684 		if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2685 			struct ieee80211_hdr *hdr =
2686 				(struct ieee80211_hdr *) skb->data;
2687 			/* more buffered multicast/broadcast frames ==> set
2688 			 * MoreData flag in IEEE 802.11 header to inform PS
2689 			 * STAs */
2690 			hdr->frame_control |=
2691 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2692 		}
2693 
2694 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2695 			break;
2696 		dev_kfree_skb_any(skb);
2697 	}
2698 
2699 	info = IEEE80211_SKB_CB(skb);
2700 
2701 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2702 	tx.channel = local->hw.conf.channel;
2703 	info->band = tx.channel->band;
2704 
2705 	if (invoke_tx_handlers(&tx))
2706 		skb = NULL;
2707  out:
2708 	rcu_read_unlock();
2709 
2710 	return skb;
2711 }
2712 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2713 
2714 void ieee80211_tx_skb_tid(struct ieee80211_sub_if_data *sdata,
2715 			  struct sk_buff *skb, int tid)
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, ieee802_1d_to_ac[tid]);
2722 	skb->priority = tid;
2723 
2724 	/*
2725 	 * The other path calling ieee80211_xmit is from the tasklet,
2726 	 * and while we can handle concurrent transmissions locking
2727 	 * requirements are that we do not come into tx with bhs on.
2728 	 */
2729 	local_bh_disable();
2730 	ieee80211_xmit(sdata, skb);
2731 	local_bh_enable();
2732 }
2733