xref: /linux/net/mac80211/tx.c (revision 90ab5ee94171b3e28de6bb42ee30b527014e0be7)
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: local->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 	    && (local->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO)
235 	    && skb_get_queue_mapping(tx->skb) == 0)
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 		     ieee80211_is_probe_resp(hdr->frame_control) ||
453 		     ieee80211_is_auth(hdr->frame_control) ||
454 		     ieee80211_is_assoc_resp(hdr->frame_control) ||
455 		     ieee80211_is_reassoc_resp(hdr->frame_control)))
456 		return TX_CONTINUE;
457 
458 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
459 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
460 		     !(info->flags & IEEE80211_TX_CTL_POLL_RESPONSE))) {
461 		int ac = skb_get_queue_mapping(tx->skb);
462 
463 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
464 		printk(KERN_DEBUG "STA %pM aid %d: PS buffer for AC %d\n",
465 		       sta->sta.addr, sta->sta.aid, ac);
466 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
467 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
468 			purge_old_ps_buffers(tx->local);
469 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
470 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
471 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
472 			if (net_ratelimit())
473 				printk(KERN_DEBUG "%s: STA %pM TX buffer for "
474 				       "AC %d full - dropping oldest frame\n",
475 				       tx->sdata->name, sta->sta.addr, ac);
476 #endif
477 			dev_kfree_skb(old);
478 		} else
479 			tx->local->total_ps_buffered++;
480 
481 		info->control.jiffies = jiffies;
482 		info->control.vif = &tx->sdata->vif;
483 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
484 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
485 
486 		if (!timer_pending(&local->sta_cleanup))
487 			mod_timer(&local->sta_cleanup,
488 				  round_jiffies(jiffies +
489 						STA_INFO_CLEANUP_INTERVAL));
490 
491 		/*
492 		 * We queued up some frames, so the TIM bit might
493 		 * need to be set, recalculate it.
494 		 */
495 		sta_info_recalc_tim(sta);
496 
497 		return TX_QUEUED;
498 	}
499 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
500 	else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
501 		printk(KERN_DEBUG
502 		       "%s: STA %pM in PS mode, but polling/in SP -> send frame\n",
503 		       tx->sdata->name, sta->sta.addr);
504 	}
505 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
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 = NULL;
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 (tx->sdata->drop_unencrypted &&
557 		 (tx->skb->protocol != tx->sdata->control_port_protocol) &&
558 		 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
559 		 (!ieee80211_is_robust_mgmt_frame(hdr) ||
560 		  (ieee80211_is_action(hdr->frame_control) &&
561 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))) {
562 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
563 		return TX_DROP;
564 	} else
565 		tx->key = NULL;
566 
567 	if (tx->key) {
568 		bool skip_hw = false;
569 
570 		tx->key->tx_rx_count++;
571 		/* TODO: add threshold stuff again */
572 
573 		switch (tx->key->conf.cipher) {
574 		case WLAN_CIPHER_SUITE_WEP40:
575 		case WLAN_CIPHER_SUITE_WEP104:
576 		case WLAN_CIPHER_SUITE_TKIP:
577 			if (!ieee80211_is_data_present(hdr->frame_control))
578 				tx->key = NULL;
579 			break;
580 		case WLAN_CIPHER_SUITE_CCMP:
581 			if (!ieee80211_is_data_present(hdr->frame_control) &&
582 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
583 					       tx->skb))
584 				tx->key = NULL;
585 			else
586 				skip_hw = (tx->key->conf.flags &
587 					   IEEE80211_KEY_FLAG_SW_MGMT) &&
588 					ieee80211_is_mgmt(hdr->frame_control);
589 			break;
590 		case WLAN_CIPHER_SUITE_AES_CMAC:
591 			if (!ieee80211_is_mgmt(hdr->frame_control))
592 				tx->key = NULL;
593 			break;
594 		}
595 
596 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED))
597 			return TX_DROP;
598 
599 		if (!skip_hw && tx->key &&
600 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
601 			info->control.hw_key = &tx->key->conf;
602 	}
603 
604 	return TX_CONTINUE;
605 }
606 
607 static ieee80211_tx_result debug_noinline
608 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
609 {
610 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
611 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
612 	struct ieee80211_supported_band *sband;
613 	struct ieee80211_rate *rate;
614 	int i;
615 	u32 len;
616 	bool inval = false, rts = false, short_preamble = false;
617 	struct ieee80211_tx_rate_control txrc;
618 	bool assoc = false;
619 
620 	memset(&txrc, 0, sizeof(txrc));
621 
622 	sband = tx->local->hw.wiphy->bands[tx->channel->band];
623 
624 	len = min_t(u32, tx->skb->len + FCS_LEN,
625 			 tx->local->hw.wiphy->frag_threshold);
626 
627 	/* set up the tx rate control struct we give the RC algo */
628 	txrc.hw = local_to_hw(tx->local);
629 	txrc.sband = sband;
630 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
631 	txrc.skb = tx->skb;
632 	txrc.reported_rate.idx = -1;
633 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[tx->channel->band];
634 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
635 		txrc.max_rate_idx = -1;
636 	else
637 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
638 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
639 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
640 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
641 
642 	/* set up RTS protection if desired */
643 	if (len > tx->local->hw.wiphy->rts_threshold) {
644 		txrc.rts = rts = true;
645 	}
646 
647 	/*
648 	 * Use short preamble if the BSS can handle it, but not for
649 	 * management frames unless we know the receiver can handle
650 	 * that -- the management frame might be to a station that
651 	 * just wants a probe response.
652 	 */
653 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
654 	    (ieee80211_is_data(hdr->frame_control) ||
655 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
656 		txrc.short_preamble = short_preamble = true;
657 
658 	if (tx->sta)
659 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
660 
661 	/*
662 	 * Lets not bother rate control if we're associated and cannot
663 	 * talk to the sta. This should not happen.
664 	 */
665 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
666 		 !rate_usable_index_exists(sband, &tx->sta->sta),
667 		 "%s: Dropped data frame as no usable bitrate found while "
668 		 "scanning and associated. Target station: "
669 		 "%pM on %d GHz band\n",
670 		 tx->sdata->name, hdr->addr1,
671 		 tx->channel->band ? 5 : 2))
672 		return TX_DROP;
673 
674 	/*
675 	 * If we're associated with the sta at this point we know we can at
676 	 * least send the frame at the lowest bit rate.
677 	 */
678 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
679 
680 	if (unlikely(info->control.rates[0].idx < 0))
681 		return TX_DROP;
682 
683 	if (txrc.reported_rate.idx < 0) {
684 		txrc.reported_rate = info->control.rates[0];
685 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
686 			tx->sta->last_tx_rate = txrc.reported_rate;
687 	} else if (tx->sta)
688 		tx->sta->last_tx_rate = txrc.reported_rate;
689 
690 	if (unlikely(!info->control.rates[0].count))
691 		info->control.rates[0].count = 1;
692 
693 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
694 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
695 		info->control.rates[0].count = 1;
696 
697 	if (is_multicast_ether_addr(hdr->addr1)) {
698 		/*
699 		 * XXX: verify the rate is in the basic rateset
700 		 */
701 		return TX_CONTINUE;
702 	}
703 
704 	/*
705 	 * set up the RTS/CTS rate as the fastest basic rate
706 	 * that is not faster than the data rate
707 	 *
708 	 * XXX: Should this check all retry rates?
709 	 */
710 	if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
711 		s8 baserate = 0;
712 
713 		rate = &sband->bitrates[info->control.rates[0].idx];
714 
715 		for (i = 0; i < sband->n_bitrates; i++) {
716 			/* must be a basic rate */
717 			if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
718 				continue;
719 			/* must not be faster than the data rate */
720 			if (sband->bitrates[i].bitrate > rate->bitrate)
721 				continue;
722 			/* maximum */
723 			if (sband->bitrates[baserate].bitrate <
724 			     sband->bitrates[i].bitrate)
725 				baserate = i;
726 		}
727 
728 		info->control.rts_cts_rate_idx = baserate;
729 	}
730 
731 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
732 		/*
733 		 * make sure there's no valid rate following
734 		 * an invalid one, just in case drivers don't
735 		 * take the API seriously to stop at -1.
736 		 */
737 		if (inval) {
738 			info->control.rates[i].idx = -1;
739 			continue;
740 		}
741 		if (info->control.rates[i].idx < 0) {
742 			inval = true;
743 			continue;
744 		}
745 
746 		/*
747 		 * For now assume MCS is already set up correctly, this
748 		 * needs to be fixed.
749 		 */
750 		if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
751 			WARN_ON(info->control.rates[i].idx > 76);
752 			continue;
753 		}
754 
755 		/* set up RTS protection if desired */
756 		if (rts)
757 			info->control.rates[i].flags |=
758 				IEEE80211_TX_RC_USE_RTS_CTS;
759 
760 		/* RC is busted */
761 		if (WARN_ON_ONCE(info->control.rates[i].idx >=
762 				 sband->n_bitrates)) {
763 			info->control.rates[i].idx = -1;
764 			continue;
765 		}
766 
767 		rate = &sband->bitrates[info->control.rates[i].idx];
768 
769 		/* set up short preamble */
770 		if (short_preamble &&
771 		    rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
772 			info->control.rates[i].flags |=
773 				IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
774 
775 		/* set up G protection */
776 		if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
777 		    rate->flags & IEEE80211_RATE_ERP_G)
778 			info->control.rates[i].flags |=
779 				IEEE80211_TX_RC_USE_CTS_PROTECT;
780 	}
781 
782 	return TX_CONTINUE;
783 }
784 
785 static ieee80211_tx_result debug_noinline
786 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
787 {
788 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
789 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
790 	u16 *seq;
791 	u8 *qc;
792 	int tid;
793 
794 	/*
795 	 * Packet injection may want to control the sequence
796 	 * number, if we have no matching interface then we
797 	 * neither assign one ourselves nor ask the driver to.
798 	 */
799 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
800 		return TX_CONTINUE;
801 
802 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
803 		return TX_CONTINUE;
804 
805 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
806 		return TX_CONTINUE;
807 
808 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
809 		return TX_CONTINUE;
810 
811 	/*
812 	 * Anything but QoS data that has a sequence number field
813 	 * (is long enough) gets a sequence number from the global
814 	 * counter.
815 	 */
816 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
817 		/* driver should assign sequence number */
818 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
819 		/* for pure STA mode without beacons, we can do it */
820 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
821 		tx->sdata->sequence_number += 0x10;
822 		return TX_CONTINUE;
823 	}
824 
825 	/*
826 	 * This should be true for injected/management frames only, for
827 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
828 	 * above since they are not QoS-data frames.
829 	 */
830 	if (!tx->sta)
831 		return TX_CONTINUE;
832 
833 	/* include per-STA, per-TID sequence counter */
834 
835 	qc = ieee80211_get_qos_ctl(hdr);
836 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
837 	seq = &tx->sta->tid_seq[tid];
838 
839 	hdr->seq_ctrl = cpu_to_le16(*seq);
840 
841 	/* Increase the sequence number. */
842 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
843 
844 	return TX_CONTINUE;
845 }
846 
847 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
848 			      struct sk_buff *skb, int hdrlen,
849 			      int frag_threshold)
850 {
851 	struct ieee80211_local *local = tx->local;
852 	struct ieee80211_tx_info *info;
853 	struct sk_buff *tmp;
854 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
855 	int pos = hdrlen + per_fragm;
856 	int rem = skb->len - hdrlen - per_fragm;
857 
858 	if (WARN_ON(rem < 0))
859 		return -EINVAL;
860 
861 	/* first fragment was already added to queue by caller */
862 
863 	while (rem) {
864 		int fraglen = per_fragm;
865 
866 		if (fraglen > rem)
867 			fraglen = rem;
868 		rem -= fraglen;
869 		tmp = dev_alloc_skb(local->tx_headroom +
870 				    frag_threshold +
871 				    IEEE80211_ENCRYPT_HEADROOM +
872 				    IEEE80211_ENCRYPT_TAILROOM);
873 		if (!tmp)
874 			return -ENOMEM;
875 
876 		__skb_queue_tail(&tx->skbs, tmp);
877 
878 		skb_reserve(tmp, local->tx_headroom +
879 				 IEEE80211_ENCRYPT_HEADROOM);
880 		/* copy control information */
881 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
882 
883 		info = IEEE80211_SKB_CB(tmp);
884 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
885 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
886 
887 		if (rem)
888 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
889 
890 		skb_copy_queue_mapping(tmp, skb);
891 		tmp->priority = skb->priority;
892 		tmp->dev = skb->dev;
893 
894 		/* copy header and data */
895 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
896 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
897 
898 		pos += fraglen;
899 	}
900 
901 	/* adjust first fragment's length */
902 	skb->len = hdrlen + per_fragm;
903 	return 0;
904 }
905 
906 static ieee80211_tx_result debug_noinline
907 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
908 {
909 	struct sk_buff *skb = tx->skb;
910 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
911 	struct ieee80211_hdr *hdr = (void *)skb->data;
912 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
913 	int hdrlen;
914 	int fragnum;
915 
916 	/* no matter what happens, tx->skb moves to tx->skbs */
917 	__skb_queue_tail(&tx->skbs, skb);
918 	tx->skb = NULL;
919 
920 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
921 		return TX_CONTINUE;
922 
923 	if (tx->local->ops->set_frag_threshold)
924 		return TX_CONTINUE;
925 
926 	/*
927 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
928 	 * This scenario is handled in ieee80211_tx_prepare but extra
929 	 * caution taken here as fragmented ampdu may cause Tx stop.
930 	 */
931 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
932 		return TX_DROP;
933 
934 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
935 
936 	/* internal error, why isn't DONTFRAG set? */
937 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
938 		return TX_DROP;
939 
940 	/*
941 	 * Now fragment the frame. This will allocate all the fragments and
942 	 * chain them (using skb as the first fragment) to skb->next.
943 	 * During transmission, we will remove the successfully transmitted
944 	 * fragments from this list. When the low-level driver rejects one
945 	 * of the fragments then we will simply pretend to accept the skb
946 	 * but store it away as pending.
947 	 */
948 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
949 		return TX_DROP;
950 
951 	/* update duration/seq/flags of fragments */
952 	fragnum = 0;
953 
954 	skb_queue_walk(&tx->skbs, skb) {
955 		int next_len;
956 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
957 
958 		hdr = (void *)skb->data;
959 		info = IEEE80211_SKB_CB(skb);
960 
961 		if (!skb_queue_is_last(&tx->skbs, skb)) {
962 			hdr->frame_control |= morefrags;
963 			/*
964 			 * No multi-rate retries for fragmented frames, that
965 			 * would completely throw off the NAV at other STAs.
966 			 */
967 			info->control.rates[1].idx = -1;
968 			info->control.rates[2].idx = -1;
969 			info->control.rates[3].idx = -1;
970 			info->control.rates[4].idx = -1;
971 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
972 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
973 		} else {
974 			hdr->frame_control &= ~morefrags;
975 			next_len = 0;
976 		}
977 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
978 		fragnum++;
979 	}
980 
981 	return TX_CONTINUE;
982 }
983 
984 static ieee80211_tx_result debug_noinline
985 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
986 {
987 	struct sk_buff *skb;
988 
989 	if (!tx->sta)
990 		return TX_CONTINUE;
991 
992 	tx->sta->tx_packets++;
993 	skb_queue_walk(&tx->skbs, skb) {
994 		tx->sta->tx_fragments++;
995 		tx->sta->tx_bytes += skb->len;
996 	}
997 
998 	return TX_CONTINUE;
999 }
1000 
1001 static ieee80211_tx_result debug_noinline
1002 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1003 {
1004 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1005 
1006 	if (!tx->key)
1007 		return TX_CONTINUE;
1008 
1009 	switch (tx->key->conf.cipher) {
1010 	case WLAN_CIPHER_SUITE_WEP40:
1011 	case WLAN_CIPHER_SUITE_WEP104:
1012 		return ieee80211_crypto_wep_encrypt(tx);
1013 	case WLAN_CIPHER_SUITE_TKIP:
1014 		return ieee80211_crypto_tkip_encrypt(tx);
1015 	case WLAN_CIPHER_SUITE_CCMP:
1016 		return ieee80211_crypto_ccmp_encrypt(tx);
1017 	case WLAN_CIPHER_SUITE_AES_CMAC:
1018 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1019 	default:
1020 		/* handle hw-only algorithm */
1021 		if (info->control.hw_key) {
1022 			ieee80211_tx_set_protected(tx);
1023 			return TX_CONTINUE;
1024 		}
1025 		break;
1026 
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 
1069 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1070 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1071 		reset_agg_timer = true;
1072 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1073 		/*
1074 		 * nothing -- this aggregation session is being started
1075 		 * but that might still fail with the driver
1076 		 */
1077 	} else {
1078 		spin_lock(&tx->sta->lock);
1079 		/*
1080 		 * Need to re-check now, because we may get here
1081 		 *
1082 		 *  1) in the window during which the setup is actually
1083 		 *     already done, but not marked yet because not all
1084 		 *     packets are spliced over to the driver pending
1085 		 *     queue yet -- if this happened we acquire the lock
1086 		 *     either before or after the splice happens, but
1087 		 *     need to recheck which of these cases happened.
1088 		 *
1089 		 *  2) during session teardown, if the OPERATIONAL bit
1090 		 *     was cleared due to the teardown but the pointer
1091 		 *     hasn't been assigned NULL yet (or we loaded it
1092 		 *     before it was assigned) -- in this case it may
1093 		 *     now be NULL which means we should just let the
1094 		 *     packet pass through because splicing the frames
1095 		 *     back is already done.
1096 		 */
1097 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1098 
1099 		if (!tid_tx) {
1100 			/* do nothing, let packet pass through */
1101 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1102 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1103 			reset_agg_timer = true;
1104 		} else {
1105 			queued = true;
1106 			info->control.vif = &tx->sdata->vif;
1107 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1108 			__skb_queue_tail(&tid_tx->pending, skb);
1109 		}
1110 		spin_unlock(&tx->sta->lock);
1111 	}
1112 
1113 	/* reset session timer */
1114 	if (reset_agg_timer && tid_tx->timeout)
1115 		mod_timer(&tid_tx->session_timer,
1116 			  TU_TO_EXP_TIME(tid_tx->timeout));
1117 
1118 	return queued;
1119 }
1120 
1121 /*
1122  * initialises @tx
1123  */
1124 static ieee80211_tx_result
1125 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1126 		     struct ieee80211_tx_data *tx,
1127 		     struct sk_buff *skb)
1128 {
1129 	struct ieee80211_local *local = sdata->local;
1130 	struct ieee80211_hdr *hdr;
1131 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1132 	int tid;
1133 	u8 *qc;
1134 
1135 	memset(tx, 0, sizeof(*tx));
1136 	tx->skb = skb;
1137 	tx->local = local;
1138 	tx->sdata = sdata;
1139 	tx->channel = local->hw.conf.channel;
1140 	__skb_queue_head_init(&tx->skbs);
1141 
1142 	/*
1143 	 * If this flag is set to true anywhere, and we get here,
1144 	 * we are doing the needed processing, so remove the flag
1145 	 * now.
1146 	 */
1147 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1148 
1149 	hdr = (struct ieee80211_hdr *) skb->data;
1150 
1151 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1152 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1153 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1154 			return TX_DROP;
1155 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED) {
1156 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1157 	}
1158 	if (!tx->sta)
1159 		tx->sta = sta_info_get(sdata, hdr->addr1);
1160 
1161 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1162 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1163 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1164 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1165 		struct tid_ampdu_tx *tid_tx;
1166 
1167 		qc = ieee80211_get_qos_ctl(hdr);
1168 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1169 
1170 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1171 		if (tid_tx) {
1172 			bool queued;
1173 
1174 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1175 						       tid_tx, tid);
1176 
1177 			if (unlikely(queued))
1178 				return TX_QUEUED;
1179 		}
1180 	}
1181 
1182 	if (is_multicast_ether_addr(hdr->addr1)) {
1183 		tx->flags &= ~IEEE80211_TX_UNICAST;
1184 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1185 	} else
1186 		tx->flags |= IEEE80211_TX_UNICAST;
1187 
1188 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1189 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1190 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1191 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1192 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1193 	}
1194 
1195 	if (!tx->sta)
1196 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1197 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1198 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1199 
1200 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1201 
1202 	return TX_CONTINUE;
1203 }
1204 
1205 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1206 			       struct ieee80211_vif *vif,
1207 			       struct ieee80211_sta *sta,
1208 			       struct sk_buff_head *skbs,
1209 			       bool txpending)
1210 {
1211 	struct sk_buff *skb, *tmp;
1212 	struct ieee80211_tx_info *info;
1213 	unsigned long flags;
1214 
1215 	skb_queue_walk_safe(skbs, skb, tmp) {
1216 		int q = skb_get_queue_mapping(skb);
1217 
1218 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1219 		if (local->queue_stop_reasons[q] ||
1220 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1221 			/*
1222 			 * Since queue is stopped, queue up frames for later
1223 			 * transmission from the tx-pending tasklet when the
1224 			 * queue is woken again.
1225 			 */
1226 			if (txpending)
1227 				skb_queue_splice_init(skbs, &local->pending[q]);
1228 			else
1229 				skb_queue_splice_tail_init(skbs,
1230 							   &local->pending[q]);
1231 
1232 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1233 					       flags);
1234 			return false;
1235 		}
1236 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1237 
1238 		info = IEEE80211_SKB_CB(skb);
1239 		info->control.vif = vif;
1240 		info->control.sta = sta;
1241 
1242 		__skb_unlink(skb, skbs);
1243 		drv_tx(local, skb);
1244 	}
1245 
1246 	return true;
1247 }
1248 
1249 /*
1250  * Returns false if the frame couldn't be transmitted but was queued instead.
1251  */
1252 static bool __ieee80211_tx(struct ieee80211_local *local,
1253 			   struct sk_buff_head *skbs, int led_len,
1254 			   struct sta_info *sta, bool txpending)
1255 {
1256 	struct ieee80211_tx_info *info;
1257 	struct ieee80211_sub_if_data *sdata;
1258 	struct ieee80211_vif *vif;
1259 	struct ieee80211_sta *pubsta;
1260 	struct sk_buff *skb;
1261 	bool result = true;
1262 	__le16 fc;
1263 
1264 	if (WARN_ON(skb_queue_empty(skbs)))
1265 		return true;
1266 
1267 	skb = skb_peek(skbs);
1268 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1269 	info = IEEE80211_SKB_CB(skb);
1270 	sdata = vif_to_sdata(info->control.vif);
1271 	if (sta && !sta->uploaded)
1272 		sta = NULL;
1273 
1274 	if (sta)
1275 		pubsta = &sta->sta;
1276 	else
1277 		pubsta = NULL;
1278 
1279 	switch (sdata->vif.type) {
1280 	case NL80211_IFTYPE_MONITOR:
1281 		sdata = NULL;
1282 		vif = NULL;
1283 		break;
1284 	case NL80211_IFTYPE_AP_VLAN:
1285 		sdata = container_of(sdata->bss,
1286 				     struct ieee80211_sub_if_data, u.ap);
1287 		/* fall through */
1288 	default:
1289 		vif = &sdata->vif;
1290 		break;
1291 	}
1292 
1293 	if (local->ops->tx_frags)
1294 		drv_tx_frags(local, vif, pubsta, skbs);
1295 	else
1296 		result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1297 					    txpending);
1298 
1299 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1300 	ieee80211_led_tx(local, 1);
1301 
1302 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1303 
1304 	return result;
1305 }
1306 
1307 /*
1308  * Invoke TX handlers, return 0 on success and non-zero if the
1309  * frame was dropped or queued.
1310  */
1311 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1312 {
1313 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1314 	ieee80211_tx_result res = TX_DROP;
1315 
1316 #define CALL_TXH(txh) \
1317 	do {				\
1318 		res = txh(tx);		\
1319 		if (res != TX_CONTINUE)	\
1320 			goto txh_done;	\
1321 	} while (0)
1322 
1323 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1324 	CALL_TXH(ieee80211_tx_h_check_assoc);
1325 	CALL_TXH(ieee80211_tx_h_ps_buf);
1326 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1327 	CALL_TXH(ieee80211_tx_h_select_key);
1328 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1329 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1330 
1331 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1332 		__skb_queue_tail(&tx->skbs, tx->skb);
1333 		tx->skb = NULL;
1334 		goto txh_done;
1335 	}
1336 
1337 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1338 	CALL_TXH(ieee80211_tx_h_sequence);
1339 	CALL_TXH(ieee80211_tx_h_fragment);
1340 	/* handlers after fragment must be aware of tx info fragmentation! */
1341 	CALL_TXH(ieee80211_tx_h_stats);
1342 	CALL_TXH(ieee80211_tx_h_encrypt);
1343 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1344 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1345 #undef CALL_TXH
1346 
1347  txh_done:
1348 	if (unlikely(res == TX_DROP)) {
1349 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1350 		if (tx->skb)
1351 			dev_kfree_skb(tx->skb);
1352 		else
1353 			__skb_queue_purge(&tx->skbs);
1354 		return -1;
1355 	} else if (unlikely(res == TX_QUEUED)) {
1356 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1357 		return -1;
1358 	}
1359 
1360 	return 0;
1361 }
1362 
1363 /*
1364  * Returns false if the frame couldn't be transmitted but was queued instead.
1365  */
1366 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1367 			 struct sk_buff *skb, bool txpending)
1368 {
1369 	struct ieee80211_local *local = sdata->local;
1370 	struct ieee80211_tx_data tx;
1371 	ieee80211_tx_result res_prepare;
1372 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1373 	bool result = true;
1374 	int led_len;
1375 
1376 	if (unlikely(skb->len < 10)) {
1377 		dev_kfree_skb(skb);
1378 		return true;
1379 	}
1380 
1381 	rcu_read_lock();
1382 
1383 	/* initialises tx */
1384 	led_len = skb->len;
1385 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1386 
1387 	if (unlikely(res_prepare == TX_DROP)) {
1388 		dev_kfree_skb(skb);
1389 		goto out;
1390 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1391 		goto out;
1392 	}
1393 
1394 	tx.channel = local->hw.conf.channel;
1395 	info->band = tx.channel->band;
1396 
1397 	if (!invoke_tx_handlers(&tx))
1398 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1399 					tx.sta, txpending);
1400  out:
1401 	rcu_read_unlock();
1402 	return result;
1403 }
1404 
1405 /* device xmit handlers */
1406 
1407 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1408 				struct sk_buff *skb,
1409 				int head_need, bool may_encrypt)
1410 {
1411 	struct ieee80211_local *local = sdata->local;
1412 	int tail_need = 0;
1413 
1414 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1415 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1416 		tail_need -= skb_tailroom(skb);
1417 		tail_need = max_t(int, tail_need, 0);
1418 	}
1419 
1420 	if (skb_cloned(skb))
1421 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1422 	else if (head_need || tail_need)
1423 		I802_DEBUG_INC(local->tx_expand_skb_head);
1424 	else
1425 		return 0;
1426 
1427 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1428 		wiphy_debug(local->hw.wiphy,
1429 			    "failed to reallocate TX buffer\n");
1430 		return -ENOMEM;
1431 	}
1432 
1433 	return 0;
1434 }
1435 
1436 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
1437 {
1438 	struct ieee80211_local *local = sdata->local;
1439 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1440 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1441 	int headroom;
1442 	bool may_encrypt;
1443 
1444 	rcu_read_lock();
1445 
1446 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1447 
1448 	headroom = local->tx_headroom;
1449 	if (may_encrypt)
1450 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1451 	headroom -= skb_headroom(skb);
1452 	headroom = max_t(int, 0, headroom);
1453 
1454 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1455 		dev_kfree_skb(skb);
1456 		rcu_read_unlock();
1457 		return;
1458 	}
1459 
1460 	hdr = (struct ieee80211_hdr *) skb->data;
1461 	info->control.vif = &sdata->vif;
1462 
1463 	if (ieee80211_vif_is_mesh(&sdata->vif) &&
1464 	    ieee80211_is_data(hdr->frame_control) &&
1465 		!is_multicast_ether_addr(hdr->addr1))
1466 			if (mesh_nexthop_resolve(skb, sdata)) {
1467 				/* skb queued: don't free */
1468 				rcu_read_unlock();
1469 				return;
1470 			}
1471 
1472 	ieee80211_set_qos_hdr(sdata, skb);
1473 	ieee80211_tx(sdata, skb, false);
1474 	rcu_read_unlock();
1475 }
1476 
1477 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1478 {
1479 	struct ieee80211_radiotap_iterator iterator;
1480 	struct ieee80211_radiotap_header *rthdr =
1481 		(struct ieee80211_radiotap_header *) skb->data;
1482 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1483 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1484 						   NULL);
1485 	u16 txflags;
1486 
1487 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1488 		       IEEE80211_TX_CTL_DONTFRAG;
1489 
1490 	/*
1491 	 * for every radiotap entry that is present
1492 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1493 	 * entries present, or -EINVAL on error)
1494 	 */
1495 
1496 	while (!ret) {
1497 		ret = ieee80211_radiotap_iterator_next(&iterator);
1498 
1499 		if (ret)
1500 			continue;
1501 
1502 		/* see if this argument is something we can use */
1503 		switch (iterator.this_arg_index) {
1504 		/*
1505 		 * You must take care when dereferencing iterator.this_arg
1506 		 * for multibyte types... the pointer is not aligned.  Use
1507 		 * get_unaligned((type *)iterator.this_arg) to dereference
1508 		 * iterator.this_arg for type "type" safely on all arches.
1509 		*/
1510 		case IEEE80211_RADIOTAP_FLAGS:
1511 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1512 				/*
1513 				 * this indicates that the skb we have been
1514 				 * handed has the 32-bit FCS CRC at the end...
1515 				 * we should react to that by snipping it off
1516 				 * because it will be recomputed and added
1517 				 * on transmission
1518 				 */
1519 				if (skb->len < (iterator._max_length + FCS_LEN))
1520 					return false;
1521 
1522 				skb_trim(skb, skb->len - FCS_LEN);
1523 			}
1524 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1525 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1526 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1527 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1528 			break;
1529 
1530 		case IEEE80211_RADIOTAP_TX_FLAGS:
1531 			txflags = get_unaligned_le16(iterator.this_arg);
1532 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1533 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1534 			break;
1535 
1536 		/*
1537 		 * Please update the file
1538 		 * Documentation/networking/mac80211-injection.txt
1539 		 * when parsing new fields here.
1540 		 */
1541 
1542 		default:
1543 			break;
1544 		}
1545 	}
1546 
1547 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1548 		return false;
1549 
1550 	/*
1551 	 * remove the radiotap header
1552 	 * iterator->_max_length was sanity-checked against
1553 	 * skb->len by iterator init
1554 	 */
1555 	skb_pull(skb, iterator._max_length);
1556 
1557 	return true;
1558 }
1559 
1560 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1561 					 struct net_device *dev)
1562 {
1563 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1564 	struct ieee80211_channel *chan = local->hw.conf.channel;
1565 	struct ieee80211_radiotap_header *prthdr =
1566 		(struct ieee80211_radiotap_header *)skb->data;
1567 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1568 	struct ieee80211_hdr *hdr;
1569 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1570 	u16 len_rthdr;
1571 	int hdrlen;
1572 
1573 	/*
1574 	 * Frame injection is not allowed if beaconing is not allowed
1575 	 * or if we need radar detection. Beaconing is usually not allowed when
1576 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1577 	 * Passive scan is also used in world regulatory domains where
1578 	 * your country is not known and as such it should be treated as
1579 	 * NO TX unless the channel is explicitly allowed in which case
1580 	 * your current regulatory domain would not have the passive scan
1581 	 * flag.
1582 	 *
1583 	 * Since AP mode uses monitor interfaces to inject/TX management
1584 	 * frames we can make AP mode the exception to this rule once it
1585 	 * supports radar detection as its implementation can deal with
1586 	 * radar detection by itself. We can do that later by adding a
1587 	 * monitor flag interfaces used for AP support.
1588 	 */
1589 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1590 	     IEEE80211_CHAN_PASSIVE_SCAN)))
1591 		goto fail;
1592 
1593 	/* check for not even having the fixed radiotap header part */
1594 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1595 		goto fail; /* too short to be possibly valid */
1596 
1597 	/* is it a header version we can trust to find length from? */
1598 	if (unlikely(prthdr->it_version))
1599 		goto fail; /* only version 0 is supported */
1600 
1601 	/* then there must be a radiotap header with a length we can use */
1602 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1603 
1604 	/* does the skb contain enough to deliver on the alleged length? */
1605 	if (unlikely(skb->len < len_rthdr))
1606 		goto fail; /* skb too short for claimed rt header extent */
1607 
1608 	/*
1609 	 * fix up the pointers accounting for the radiotap
1610 	 * header still being in there.  We are being given
1611 	 * a precooked IEEE80211 header so no need for
1612 	 * normal processing
1613 	 */
1614 	skb_set_mac_header(skb, len_rthdr);
1615 	/*
1616 	 * these are just fixed to the end of the rt area since we
1617 	 * don't have any better information and at this point, nobody cares
1618 	 */
1619 	skb_set_network_header(skb, len_rthdr);
1620 	skb_set_transport_header(skb, len_rthdr);
1621 
1622 	if (skb->len < len_rthdr + 2)
1623 		goto fail;
1624 
1625 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1626 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1627 
1628 	if (skb->len < len_rthdr + hdrlen)
1629 		goto fail;
1630 
1631 	/*
1632 	 * Initialize skb->protocol if the injected frame is a data frame
1633 	 * carrying a rfc1042 header
1634 	 */
1635 	if (ieee80211_is_data(hdr->frame_control) &&
1636 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1637 		u8 *payload = (u8 *)hdr + hdrlen;
1638 
1639 		if (compare_ether_addr(payload, rfc1042_header) == 0)
1640 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1641 						    payload[7]);
1642 	}
1643 
1644 	memset(info, 0, sizeof(*info));
1645 
1646 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1647 		      IEEE80211_TX_CTL_INJECTED;
1648 
1649 	/* process and remove the injection radiotap header */
1650 	if (!ieee80211_parse_tx_radiotap(skb))
1651 		goto fail;
1652 
1653 	rcu_read_lock();
1654 
1655 	/*
1656 	 * We process outgoing injected frames that have a local address
1657 	 * we handle as though they are non-injected frames.
1658 	 * This code here isn't entirely correct, the local MAC address
1659 	 * isn't always enough to find the interface to use; for proper
1660 	 * VLAN/WDS support we will need a different mechanism (which
1661 	 * likely isn't going to be monitor interfaces).
1662 	 */
1663 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1664 
1665 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1666 		if (!ieee80211_sdata_running(tmp_sdata))
1667 			continue;
1668 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1669 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1670 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1671 			continue;
1672 		if (compare_ether_addr(tmp_sdata->vif.addr, hdr->addr2) == 0) {
1673 			sdata = tmp_sdata;
1674 			break;
1675 		}
1676 	}
1677 
1678 	ieee80211_xmit(sdata, skb);
1679 	rcu_read_unlock();
1680 
1681 	return NETDEV_TX_OK;
1682 
1683 fail:
1684 	dev_kfree_skb(skb);
1685 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1686 }
1687 
1688 /**
1689  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1690  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1691  * @skb: packet to be sent
1692  * @dev: incoming interface
1693  *
1694  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1695  * not be freed, and caller is responsible for either retrying later or freeing
1696  * skb).
1697  *
1698  * This function takes in an Ethernet header and encapsulates it with suitable
1699  * IEEE 802.11 header based on which interface the packet is coming in. The
1700  * encapsulated packet will then be passed to master interface, wlan#.11, for
1701  * transmission (through low-level driver).
1702  */
1703 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1704 				    struct net_device *dev)
1705 {
1706 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1707 	struct ieee80211_local *local = sdata->local;
1708 	struct ieee80211_tx_info *info;
1709 	int ret = NETDEV_TX_BUSY, head_need;
1710 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1711 	__le16 fc;
1712 	struct ieee80211_hdr hdr;
1713 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1714 	struct mesh_path __maybe_unused *mppath = NULL;
1715 	const u8 *encaps_data;
1716 	int encaps_len, skip_header_bytes;
1717 	int nh_pos, h_pos;
1718 	struct sta_info *sta = NULL;
1719 	bool wme_sta = false, authorized = false, tdls_auth = false;
1720 	bool tdls_direct = false;
1721 	bool multicast;
1722 	u32 info_flags = 0;
1723 	u16 info_id = 0;
1724 
1725 	if (unlikely(skb->len < ETH_HLEN)) {
1726 		ret = NETDEV_TX_OK;
1727 		goto fail;
1728 	}
1729 
1730 	/* convert Ethernet header to proper 802.11 header (based on
1731 	 * operation mode) */
1732 	ethertype = (skb->data[12] << 8) | skb->data[13];
1733 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1734 
1735 	switch (sdata->vif.type) {
1736 	case NL80211_IFTYPE_AP_VLAN:
1737 		rcu_read_lock();
1738 		sta = rcu_dereference(sdata->u.vlan.sta);
1739 		if (sta) {
1740 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1741 			/* RA TA DA SA */
1742 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1743 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1744 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1745 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1746 			hdrlen = 30;
1747 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1748 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1749 		}
1750 		rcu_read_unlock();
1751 		if (sta)
1752 			break;
1753 		/* fall through */
1754 	case NL80211_IFTYPE_AP:
1755 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1756 		/* DA BSSID SA */
1757 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1758 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1759 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1760 		hdrlen = 24;
1761 		break;
1762 	case NL80211_IFTYPE_WDS:
1763 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1764 		/* RA TA DA SA */
1765 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1766 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1767 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1768 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1769 		hdrlen = 30;
1770 		break;
1771 #ifdef CONFIG_MAC80211_MESH
1772 	case NL80211_IFTYPE_MESH_POINT:
1773 		if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1774 			/* Do not send frames with mesh_ttl == 0 */
1775 			sdata->u.mesh.mshstats.dropped_frames_ttl++;
1776 			ret = NETDEV_TX_OK;
1777 			goto fail;
1778 		}
1779 		rcu_read_lock();
1780 		if (!is_multicast_ether_addr(skb->data))
1781 			mppath = mpp_path_lookup(skb->data, sdata);
1782 
1783 		/*
1784 		 * Use address extension if it is a packet from
1785 		 * another interface or if we know the destination
1786 		 * is being proxied by a portal (i.e. portal address
1787 		 * differs from proxied address)
1788 		 */
1789 		if (compare_ether_addr(sdata->vif.addr,
1790 				       skb->data + ETH_ALEN) == 0 &&
1791 		    !(mppath && compare_ether_addr(mppath->mpp, skb->data))) {
1792 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1793 					skb->data, skb->data + ETH_ALEN);
1794 			rcu_read_unlock();
1795 			meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
1796 					sdata, NULL, NULL);
1797 		} else {
1798 			int is_mesh_mcast = 1;
1799 			const u8 *mesh_da;
1800 
1801 			if (is_multicast_ether_addr(skb->data))
1802 				/* DA TA mSA AE:SA */
1803 				mesh_da = skb->data;
1804 			else {
1805 				static const u8 bcast[ETH_ALEN] =
1806 					{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
1807 				if (mppath) {
1808 					/* RA TA mDA mSA AE:DA SA */
1809 					mesh_da = mppath->mpp;
1810 					is_mesh_mcast = 0;
1811 				} else {
1812 					/* DA TA mSA AE:SA */
1813 					mesh_da = bcast;
1814 				}
1815 			}
1816 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1817 					mesh_da, sdata->vif.addr);
1818 			rcu_read_unlock();
1819 			if (is_mesh_mcast)
1820 				meshhdrlen =
1821 					ieee80211_new_mesh_header(&mesh_hdr,
1822 							sdata,
1823 							skb->data + ETH_ALEN,
1824 							NULL);
1825 			else
1826 				meshhdrlen =
1827 					ieee80211_new_mesh_header(&mesh_hdr,
1828 							sdata,
1829 							skb->data,
1830 							skb->data + ETH_ALEN);
1831 
1832 		}
1833 		break;
1834 #endif
1835 	case NL80211_IFTYPE_STATION:
1836 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1837 			bool tdls_peer = false;
1838 
1839 			rcu_read_lock();
1840 			sta = sta_info_get(sdata, skb->data);
1841 			if (sta) {
1842 				authorized = test_sta_flag(sta,
1843 							WLAN_STA_AUTHORIZED);
1844 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1845 				tdls_peer = test_sta_flag(sta,
1846 							 WLAN_STA_TDLS_PEER);
1847 				tdls_auth = test_sta_flag(sta,
1848 						WLAN_STA_TDLS_PEER_AUTH);
1849 			}
1850 			rcu_read_unlock();
1851 
1852 			/*
1853 			 * If the TDLS link is enabled, send everything
1854 			 * directly. Otherwise, allow TDLS setup frames
1855 			 * to be transmitted indirectly.
1856 			 */
1857 			tdls_direct = tdls_peer && (tdls_auth ||
1858 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1859 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1860 		}
1861 
1862 		if (tdls_direct) {
1863 			/* link during setup - throw out frames to peer */
1864 			if (!tdls_auth) {
1865 				ret = NETDEV_TX_OK;
1866 				goto fail;
1867 			}
1868 
1869 			/* DA SA BSSID */
1870 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1871 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1872 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1873 			hdrlen = 24;
1874 		}  else if (sdata->u.mgd.use_4addr &&
1875 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1876 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1877 					  IEEE80211_FCTL_TODS);
1878 			/* RA TA DA SA */
1879 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1880 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1881 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1882 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1883 			hdrlen = 30;
1884 		} else {
1885 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1886 			/* BSSID SA DA */
1887 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1888 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1889 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1890 			hdrlen = 24;
1891 		}
1892 		break;
1893 	case NL80211_IFTYPE_ADHOC:
1894 		/* DA SA BSSID */
1895 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1896 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1897 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1898 		hdrlen = 24;
1899 		break;
1900 	default:
1901 		ret = NETDEV_TX_OK;
1902 		goto fail;
1903 	}
1904 
1905 	/*
1906 	 * There's no need to try to look up the destination
1907 	 * if it is a multicast address (which can only happen
1908 	 * in AP mode)
1909 	 */
1910 	multicast = is_multicast_ether_addr(hdr.addr1);
1911 	if (!multicast) {
1912 		rcu_read_lock();
1913 		sta = sta_info_get(sdata, hdr.addr1);
1914 		if (sta) {
1915 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1916 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1917 		}
1918 		rcu_read_unlock();
1919 	}
1920 
1921 	/* For mesh, the use of the QoS header is mandatory */
1922 	if (ieee80211_vif_is_mesh(&sdata->vif))
1923 		wme_sta = true;
1924 
1925 	/* receiver and we are QoS enabled, use a QoS type frame */
1926 	if (wme_sta && local->hw.queues >= 4) {
1927 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1928 		hdrlen += 2;
1929 	}
1930 
1931 	/*
1932 	 * Drop unicast frames to unauthorised stations unless they are
1933 	 * EAPOL frames from the local station.
1934 	 */
1935 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
1936 		     !is_multicast_ether_addr(hdr.addr1) && !authorized &&
1937 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
1938 		      compare_ether_addr(sdata->vif.addr, skb->data + ETH_ALEN)))) {
1939 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1940 		if (net_ratelimit())
1941 			printk(KERN_DEBUG "%s: dropped frame to %pM"
1942 			       " (unauthorized port)\n", dev->name,
1943 			       hdr.addr1);
1944 #endif
1945 
1946 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1947 
1948 		ret = NETDEV_TX_OK;
1949 		goto fail;
1950 	}
1951 
1952 	if (unlikely(!multicast && skb->sk &&
1953 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
1954 		struct sk_buff *orig_skb = skb;
1955 
1956 		skb = skb_clone(skb, GFP_ATOMIC);
1957 		if (skb) {
1958 			unsigned long flags;
1959 			int id, r;
1960 
1961 			spin_lock_irqsave(&local->ack_status_lock, flags);
1962 			r = idr_get_new_above(&local->ack_status_frames,
1963 					      orig_skb, 1, &id);
1964 			if (r == -EAGAIN) {
1965 				idr_pre_get(&local->ack_status_frames,
1966 					    GFP_ATOMIC);
1967 				r = idr_get_new_above(&local->ack_status_frames,
1968 						      orig_skb, 1, &id);
1969 			}
1970 			if (WARN_ON(!id) || id > 0xffff) {
1971 				idr_remove(&local->ack_status_frames, id);
1972 				r = -ERANGE;
1973 			}
1974 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
1975 
1976 			if (!r) {
1977 				info_id = id;
1978 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1979 			} else if (skb_shared(skb)) {
1980 				kfree_skb(orig_skb);
1981 			} else {
1982 				kfree_skb(skb);
1983 				skb = orig_skb;
1984 			}
1985 		} else {
1986 			/* couldn't clone -- lose tx status ... */
1987 			skb = orig_skb;
1988 		}
1989 	}
1990 
1991 	/*
1992 	 * If the skb is shared we need to obtain our own copy.
1993 	 */
1994 	if (skb_shared(skb)) {
1995 		struct sk_buff *tmp_skb = skb;
1996 
1997 		/* can't happen -- skb is a clone if info_id != 0 */
1998 		WARN_ON(info_id);
1999 
2000 		skb = skb_clone(skb, GFP_ATOMIC);
2001 		kfree_skb(tmp_skb);
2002 
2003 		if (!skb) {
2004 			ret = NETDEV_TX_OK;
2005 			goto fail;
2006 		}
2007 	}
2008 
2009 	hdr.frame_control = fc;
2010 	hdr.duration_id = 0;
2011 	hdr.seq_ctrl = 0;
2012 
2013 	skip_header_bytes = ETH_HLEN;
2014 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2015 		encaps_data = bridge_tunnel_header;
2016 		encaps_len = sizeof(bridge_tunnel_header);
2017 		skip_header_bytes -= 2;
2018 	} else if (ethertype >= 0x600) {
2019 		encaps_data = rfc1042_header;
2020 		encaps_len = sizeof(rfc1042_header);
2021 		skip_header_bytes -= 2;
2022 	} else {
2023 		encaps_data = NULL;
2024 		encaps_len = 0;
2025 	}
2026 
2027 	nh_pos = skb_network_header(skb) - skb->data;
2028 	h_pos = skb_transport_header(skb) - skb->data;
2029 
2030 	skb_pull(skb, skip_header_bytes);
2031 	nh_pos -= skip_header_bytes;
2032 	h_pos -= skip_header_bytes;
2033 
2034 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2035 
2036 	/*
2037 	 * So we need to modify the skb header and hence need a copy of
2038 	 * that. The head_need variable above doesn't, so far, include
2039 	 * the needed header space that we don't need right away. If we
2040 	 * can, then we don't reallocate right now but only after the
2041 	 * frame arrives at the master device (if it does...)
2042 	 *
2043 	 * If we cannot, however, then we will reallocate to include all
2044 	 * the ever needed space. Also, if we need to reallocate it anyway,
2045 	 * make it big enough for everything we may ever need.
2046 	 */
2047 
2048 	if (head_need > 0 || skb_cloned(skb)) {
2049 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2050 		head_need += local->tx_headroom;
2051 		head_need = max_t(int, 0, head_need);
2052 		if (ieee80211_skb_resize(sdata, skb, head_need, true))
2053 			goto fail;
2054 	}
2055 
2056 	if (encaps_data) {
2057 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2058 		nh_pos += encaps_len;
2059 		h_pos += encaps_len;
2060 	}
2061 
2062 #ifdef CONFIG_MAC80211_MESH
2063 	if (meshhdrlen > 0) {
2064 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2065 		nh_pos += meshhdrlen;
2066 		h_pos += meshhdrlen;
2067 	}
2068 #endif
2069 
2070 	if (ieee80211_is_data_qos(fc)) {
2071 		__le16 *qos_control;
2072 
2073 		qos_control = (__le16*) skb_push(skb, 2);
2074 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2075 		/*
2076 		 * Maybe we could actually set some fields here, for now just
2077 		 * initialise to zero to indicate no special operation.
2078 		 */
2079 		*qos_control = 0;
2080 	} else
2081 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2082 
2083 	nh_pos += hdrlen;
2084 	h_pos += hdrlen;
2085 
2086 	dev->stats.tx_packets++;
2087 	dev->stats.tx_bytes += skb->len;
2088 
2089 	/* Update skb pointers to various headers since this modified frame
2090 	 * is going to go through Linux networking code that may potentially
2091 	 * need things like pointer to IP header. */
2092 	skb_set_mac_header(skb, 0);
2093 	skb_set_network_header(skb, nh_pos);
2094 	skb_set_transport_header(skb, h_pos);
2095 
2096 	info = IEEE80211_SKB_CB(skb);
2097 	memset(info, 0, sizeof(*info));
2098 
2099 	dev->trans_start = jiffies;
2100 
2101 	info->flags = info_flags;
2102 	info->ack_frame_id = info_id;
2103 
2104 	ieee80211_xmit(sdata, skb);
2105 
2106 	return NETDEV_TX_OK;
2107 
2108  fail:
2109 	if (ret == NETDEV_TX_OK)
2110 		dev_kfree_skb(skb);
2111 
2112 	return ret;
2113 }
2114 
2115 
2116 /*
2117  * ieee80211_clear_tx_pending may not be called in a context where
2118  * it is possible that it packets could come in again.
2119  */
2120 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2121 {
2122 	int i;
2123 
2124 	for (i = 0; i < local->hw.queues; i++)
2125 		skb_queue_purge(&local->pending[i]);
2126 }
2127 
2128 /*
2129  * Returns false if the frame couldn't be transmitted but was queued instead,
2130  * which in this case means re-queued -- take as an indication to stop sending
2131  * more pending frames.
2132  */
2133 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2134 				     struct sk_buff *skb)
2135 {
2136 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2137 	struct ieee80211_sub_if_data *sdata;
2138 	struct sta_info *sta;
2139 	struct ieee80211_hdr *hdr;
2140 	bool result;
2141 
2142 	sdata = vif_to_sdata(info->control.vif);
2143 
2144 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2145 		result = ieee80211_tx(sdata, skb, true);
2146 	} else {
2147 		struct sk_buff_head skbs;
2148 
2149 		__skb_queue_head_init(&skbs);
2150 		__skb_queue_tail(&skbs, skb);
2151 
2152 		hdr = (struct ieee80211_hdr *)skb->data;
2153 		sta = sta_info_get(sdata, hdr->addr1);
2154 
2155 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2156 	}
2157 
2158 	return result;
2159 }
2160 
2161 /*
2162  * Transmit all pending packets. Called from tasklet.
2163  */
2164 void ieee80211_tx_pending(unsigned long data)
2165 {
2166 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2167 	struct ieee80211_sub_if_data *sdata;
2168 	unsigned long flags;
2169 	int i;
2170 	bool txok;
2171 
2172 	rcu_read_lock();
2173 
2174 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2175 	for (i = 0; i < local->hw.queues; i++) {
2176 		/*
2177 		 * If queue is stopped by something other than due to pending
2178 		 * frames, or we have no pending frames, proceed to next queue.
2179 		 */
2180 		if (local->queue_stop_reasons[i] ||
2181 		    skb_queue_empty(&local->pending[i]))
2182 			continue;
2183 
2184 		while (!skb_queue_empty(&local->pending[i])) {
2185 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2186 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2187 
2188 			if (WARN_ON(!info->control.vif)) {
2189 				kfree_skb(skb);
2190 				continue;
2191 			}
2192 
2193 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2194 						flags);
2195 
2196 			txok = ieee80211_tx_pending_skb(local, skb);
2197 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2198 					  flags);
2199 			if (!txok)
2200 				break;
2201 		}
2202 
2203 		if (skb_queue_empty(&local->pending[i]))
2204 			list_for_each_entry_rcu(sdata, &local->interfaces, list)
2205 				netif_wake_subqueue(sdata->dev, i);
2206 	}
2207 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2208 
2209 	rcu_read_unlock();
2210 }
2211 
2212 /* functions for drivers to get certain frames */
2213 
2214 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
2215 				     struct sk_buff *skb,
2216 				     struct beacon_data *beacon)
2217 {
2218 	u8 *pos, *tim;
2219 	int aid0 = 0;
2220 	int i, have_bits = 0, n1, n2;
2221 
2222 	/* Generate bitmap for TIM only if there are any STAs in power save
2223 	 * mode. */
2224 	if (atomic_read(&bss->num_sta_ps) > 0)
2225 		/* in the hope that this is faster than
2226 		 * checking byte-for-byte */
2227 		have_bits = !bitmap_empty((unsigned long*)bss->tim,
2228 					  IEEE80211_MAX_AID+1);
2229 
2230 	if (bss->dtim_count == 0)
2231 		bss->dtim_count = beacon->dtim_period - 1;
2232 	else
2233 		bss->dtim_count--;
2234 
2235 	tim = pos = (u8 *) skb_put(skb, 6);
2236 	*pos++ = WLAN_EID_TIM;
2237 	*pos++ = 4;
2238 	*pos++ = bss->dtim_count;
2239 	*pos++ = beacon->dtim_period;
2240 
2241 	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
2242 		aid0 = 1;
2243 
2244 	bss->dtim_bc_mc = aid0 == 1;
2245 
2246 	if (have_bits) {
2247 		/* Find largest even number N1 so that bits numbered 1 through
2248 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2249 		 * (N2 + 1) x 8 through 2007 are 0. */
2250 		n1 = 0;
2251 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2252 			if (bss->tim[i]) {
2253 				n1 = i & 0xfe;
2254 				break;
2255 			}
2256 		}
2257 		n2 = n1;
2258 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2259 			if (bss->tim[i]) {
2260 				n2 = i;
2261 				break;
2262 			}
2263 		}
2264 
2265 		/* Bitmap control */
2266 		*pos++ = n1 | aid0;
2267 		/* Part Virt Bitmap */
2268 		skb_put(skb, n2 - n1);
2269 		memcpy(pos, bss->tim + n1, n2 - n1 + 1);
2270 
2271 		tim[1] = n2 - n1 + 4;
2272 	} else {
2273 		*pos++ = aid0; /* Bitmap control */
2274 		*pos++ = 0; /* Part Virt Bitmap */
2275 	}
2276 }
2277 
2278 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2279 					 struct ieee80211_vif *vif,
2280 					 u16 *tim_offset, u16 *tim_length)
2281 {
2282 	struct ieee80211_local *local = hw_to_local(hw);
2283 	struct sk_buff *skb = NULL;
2284 	struct ieee80211_tx_info *info;
2285 	struct ieee80211_sub_if_data *sdata = NULL;
2286 	struct ieee80211_if_ap *ap = NULL;
2287 	struct beacon_data *beacon;
2288 	struct ieee80211_supported_band *sband;
2289 	enum ieee80211_band band = local->hw.conf.channel->band;
2290 	struct ieee80211_tx_rate_control txrc;
2291 
2292 	sband = local->hw.wiphy->bands[band];
2293 
2294 	rcu_read_lock();
2295 
2296 	sdata = vif_to_sdata(vif);
2297 
2298 	if (!ieee80211_sdata_running(sdata))
2299 		goto out;
2300 
2301 	if (tim_offset)
2302 		*tim_offset = 0;
2303 	if (tim_length)
2304 		*tim_length = 0;
2305 
2306 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2307 		ap = &sdata->u.ap;
2308 		beacon = rcu_dereference(ap->beacon);
2309 		if (beacon) {
2310 			/*
2311 			 * headroom, head length,
2312 			 * tail length and maximum TIM length
2313 			 */
2314 			skb = dev_alloc_skb(local->tx_headroom +
2315 					    beacon->head_len +
2316 					    beacon->tail_len + 256);
2317 			if (!skb)
2318 				goto out;
2319 
2320 			skb_reserve(skb, local->tx_headroom);
2321 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2322 			       beacon->head_len);
2323 
2324 			/*
2325 			 * Not very nice, but we want to allow the driver to call
2326 			 * ieee80211_beacon_get() as a response to the set_tim()
2327 			 * callback. That, however, is already invoked under the
2328 			 * sta_lock to guarantee consistent and race-free update
2329 			 * of the tim bitmap in mac80211 and the driver.
2330 			 */
2331 			if (local->tim_in_locked_section) {
2332 				ieee80211_beacon_add_tim(ap, skb, beacon);
2333 			} else {
2334 				unsigned long flags;
2335 
2336 				spin_lock_irqsave(&local->tim_lock, flags);
2337 				ieee80211_beacon_add_tim(ap, skb, beacon);
2338 				spin_unlock_irqrestore(&local->tim_lock, flags);
2339 			}
2340 
2341 			if (tim_offset)
2342 				*tim_offset = beacon->head_len;
2343 			if (tim_length)
2344 				*tim_length = skb->len - beacon->head_len;
2345 
2346 			if (beacon->tail)
2347 				memcpy(skb_put(skb, beacon->tail_len),
2348 				       beacon->tail, beacon->tail_len);
2349 		} else
2350 			goto out;
2351 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2352 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2353 		struct ieee80211_hdr *hdr;
2354 		struct sk_buff *presp = rcu_dereference(ifibss->presp);
2355 
2356 		if (!presp)
2357 			goto out;
2358 
2359 		skb = skb_copy(presp, GFP_ATOMIC);
2360 		if (!skb)
2361 			goto out;
2362 
2363 		hdr = (struct ieee80211_hdr *) skb->data;
2364 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2365 						 IEEE80211_STYPE_BEACON);
2366 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2367 		struct ieee80211_mgmt *mgmt;
2368 		u8 *pos;
2369 		int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
2370 			      sizeof(mgmt->u.beacon);
2371 
2372 #ifdef CONFIG_MAC80211_MESH
2373 		if (!sdata->u.mesh.mesh_id_len)
2374 			goto out;
2375 #endif
2376 
2377 		skb = dev_alloc_skb(local->tx_headroom +
2378 				    hdr_len +
2379 				    2 + /* NULL SSID */
2380 				    2 + 8 + /* supported rates */
2381 				    2 + 3 + /* DS params */
2382 				    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2383 				    2 + sizeof(struct ieee80211_ht_cap) +
2384 				    2 + sizeof(struct ieee80211_ht_info) +
2385 				    2 + sdata->u.mesh.mesh_id_len +
2386 				    2 + sizeof(struct ieee80211_meshconf_ie) +
2387 				    sdata->u.mesh.ie_len);
2388 		if (!skb)
2389 			goto out;
2390 
2391 		skb_reserve(skb, local->hw.extra_tx_headroom);
2392 		mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
2393 		memset(mgmt, 0, hdr_len);
2394 		mgmt->frame_control =
2395 		    cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2396 		memset(mgmt->da, 0xff, ETH_ALEN);
2397 		memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
2398 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
2399 		mgmt->u.beacon.beacon_int =
2400 			cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2401 		mgmt->u.beacon.capab_info |= cpu_to_le16(
2402 			sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
2403 
2404 		pos = skb_put(skb, 2);
2405 		*pos++ = WLAN_EID_SSID;
2406 		*pos++ = 0x0;
2407 
2408 		if (ieee80211_add_srates_ie(&sdata->vif, skb) ||
2409 		    mesh_add_ds_params_ie(skb, sdata) ||
2410 		    ieee80211_add_ext_srates_ie(&sdata->vif, skb) ||
2411 		    mesh_add_rsn_ie(skb, sdata) ||
2412 		    mesh_add_ht_cap_ie(skb, sdata) ||
2413 		    mesh_add_ht_info_ie(skb, sdata) ||
2414 		    mesh_add_meshid_ie(skb, sdata) ||
2415 		    mesh_add_meshconf_ie(skb, sdata) ||
2416 		    mesh_add_vendor_ies(skb, sdata)) {
2417 			pr_err("o11s: couldn't add ies!\n");
2418 			goto out;
2419 		}
2420 	} else {
2421 		WARN_ON(1);
2422 		goto out;
2423 	}
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 = sband;
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 << 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 *presp = NULL, *skb = NULL;
2461 	struct ieee80211_hdr *hdr;
2462 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2463 
2464 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2465 		return NULL;
2466 
2467 	rcu_read_lock();
2468 
2469 	ap = &sdata->u.ap;
2470 	presp = rcu_dereference(ap->probe_resp);
2471 	if (!presp)
2472 		goto out;
2473 
2474 	skb = skb_copy(presp, GFP_ATOMIC);
2475 	if (!skb)
2476 		goto out;
2477 
2478 	hdr = (struct ieee80211_hdr *) skb->data;
2479 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2480 
2481 out:
2482 	rcu_read_unlock();
2483 	return skb;
2484 }
2485 EXPORT_SYMBOL(ieee80211_proberesp_get);
2486 
2487 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2488 				     struct ieee80211_vif *vif)
2489 {
2490 	struct ieee80211_sub_if_data *sdata;
2491 	struct ieee80211_if_managed *ifmgd;
2492 	struct ieee80211_pspoll *pspoll;
2493 	struct ieee80211_local *local;
2494 	struct sk_buff *skb;
2495 
2496 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2497 		return NULL;
2498 
2499 	sdata = vif_to_sdata(vif);
2500 	ifmgd = &sdata->u.mgd;
2501 	local = sdata->local;
2502 
2503 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2504 	if (!skb)
2505 		return NULL;
2506 
2507 	skb_reserve(skb, local->hw.extra_tx_headroom);
2508 
2509 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2510 	memset(pspoll, 0, sizeof(*pspoll));
2511 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2512 					    IEEE80211_STYPE_PSPOLL);
2513 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2514 
2515 	/* aid in PS-Poll has its two MSBs each set to 1 */
2516 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2517 
2518 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2519 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2520 
2521 	return skb;
2522 }
2523 EXPORT_SYMBOL(ieee80211_pspoll_get);
2524 
2525 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2526 				       struct ieee80211_vif *vif)
2527 {
2528 	struct ieee80211_hdr_3addr *nullfunc;
2529 	struct ieee80211_sub_if_data *sdata;
2530 	struct ieee80211_if_managed *ifmgd;
2531 	struct ieee80211_local *local;
2532 	struct sk_buff *skb;
2533 
2534 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2535 		return NULL;
2536 
2537 	sdata = vif_to_sdata(vif);
2538 	ifmgd = &sdata->u.mgd;
2539 	local = sdata->local;
2540 
2541 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2542 	if (!skb)
2543 		return NULL;
2544 
2545 	skb_reserve(skb, local->hw.extra_tx_headroom);
2546 
2547 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2548 							  sizeof(*nullfunc));
2549 	memset(nullfunc, 0, sizeof(*nullfunc));
2550 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2551 					      IEEE80211_STYPE_NULLFUNC |
2552 					      IEEE80211_FCTL_TODS);
2553 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2554 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2555 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2556 
2557 	return skb;
2558 }
2559 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2560 
2561 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2562 				       struct ieee80211_vif *vif,
2563 				       const u8 *ssid, size_t ssid_len,
2564 				       const u8 *ie, size_t ie_len)
2565 {
2566 	struct ieee80211_sub_if_data *sdata;
2567 	struct ieee80211_local *local;
2568 	struct ieee80211_hdr_3addr *hdr;
2569 	struct sk_buff *skb;
2570 	size_t ie_ssid_len;
2571 	u8 *pos;
2572 
2573 	sdata = vif_to_sdata(vif);
2574 	local = sdata->local;
2575 	ie_ssid_len = 2 + ssid_len;
2576 
2577 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2578 			    ie_ssid_len + ie_len);
2579 	if (!skb)
2580 		return NULL;
2581 
2582 	skb_reserve(skb, local->hw.extra_tx_headroom);
2583 
2584 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2585 	memset(hdr, 0, sizeof(*hdr));
2586 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2587 					 IEEE80211_STYPE_PROBE_REQ);
2588 	memset(hdr->addr1, 0xff, ETH_ALEN);
2589 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2590 	memset(hdr->addr3, 0xff, ETH_ALEN);
2591 
2592 	pos = skb_put(skb, ie_ssid_len);
2593 	*pos++ = WLAN_EID_SSID;
2594 	*pos++ = ssid_len;
2595 	if (ssid)
2596 		memcpy(pos, ssid, ssid_len);
2597 	pos += ssid_len;
2598 
2599 	if (ie) {
2600 		pos = skb_put(skb, ie_len);
2601 		memcpy(pos, ie, ie_len);
2602 	}
2603 
2604 	return skb;
2605 }
2606 EXPORT_SYMBOL(ieee80211_probereq_get);
2607 
2608 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2609 		       const void *frame, size_t frame_len,
2610 		       const struct ieee80211_tx_info *frame_txctl,
2611 		       struct ieee80211_rts *rts)
2612 {
2613 	const struct ieee80211_hdr *hdr = frame;
2614 
2615 	rts->frame_control =
2616 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2617 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2618 					       frame_txctl);
2619 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2620 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2621 }
2622 EXPORT_SYMBOL(ieee80211_rts_get);
2623 
2624 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2625 			     const void *frame, size_t frame_len,
2626 			     const struct ieee80211_tx_info *frame_txctl,
2627 			     struct ieee80211_cts *cts)
2628 {
2629 	const struct ieee80211_hdr *hdr = frame;
2630 
2631 	cts->frame_control =
2632 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2633 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2634 						     frame_len, frame_txctl);
2635 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2636 }
2637 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2638 
2639 struct sk_buff *
2640 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2641 			  struct ieee80211_vif *vif)
2642 {
2643 	struct ieee80211_local *local = hw_to_local(hw);
2644 	struct sk_buff *skb = NULL;
2645 	struct ieee80211_tx_data tx;
2646 	struct ieee80211_sub_if_data *sdata;
2647 	struct ieee80211_if_ap *bss = NULL;
2648 	struct beacon_data *beacon;
2649 	struct ieee80211_tx_info *info;
2650 
2651 	sdata = vif_to_sdata(vif);
2652 	bss = &sdata->u.ap;
2653 
2654 	rcu_read_lock();
2655 	beacon = rcu_dereference(bss->beacon);
2656 
2657 	if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2658 		goto out;
2659 
2660 	if (bss->dtim_count != 0 || !bss->dtim_bc_mc)
2661 		goto out; /* send buffered bc/mc only after DTIM beacon */
2662 
2663 	while (1) {
2664 		skb = skb_dequeue(&bss->ps_bc_buf);
2665 		if (!skb)
2666 			goto out;
2667 		local->total_ps_buffered--;
2668 
2669 		if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2670 			struct ieee80211_hdr *hdr =
2671 				(struct ieee80211_hdr *) skb->data;
2672 			/* more buffered multicast/broadcast frames ==> set
2673 			 * MoreData flag in IEEE 802.11 header to inform PS
2674 			 * STAs */
2675 			hdr->frame_control |=
2676 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2677 		}
2678 
2679 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2680 			break;
2681 		dev_kfree_skb_any(skb);
2682 	}
2683 
2684 	info = IEEE80211_SKB_CB(skb);
2685 
2686 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2687 	tx.channel = local->hw.conf.channel;
2688 	info->band = tx.channel->band;
2689 
2690 	if (invoke_tx_handlers(&tx))
2691 		skb = NULL;
2692  out:
2693 	rcu_read_unlock();
2694 
2695 	return skb;
2696 }
2697 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2698 
2699 void ieee80211_tx_skb_tid(struct ieee80211_sub_if_data *sdata,
2700 			  struct sk_buff *skb, int tid)
2701 {
2702 	skb_set_mac_header(skb, 0);
2703 	skb_set_network_header(skb, 0);
2704 	skb_set_transport_header(skb, 0);
2705 
2706 	skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]);
2707 	skb->priority = tid;
2708 
2709 	/*
2710 	 * The other path calling ieee80211_xmit is from the tasklet,
2711 	 * and while we can handle concurrent transmissions locking
2712 	 * requirements are that we do not come into tx with bhs on.
2713 	 */
2714 	local_bh_disable();
2715 	ieee80211_xmit(sdata, skb);
2716 	local_bh_enable();
2717 }
2718