xref: /linux/net/mac80211/rx.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
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 2007-2010	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 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <linux/export.h>
20 #include <net/mac80211.h>
21 #include <net/ieee80211_radiotap.h>
22 #include <asm/unaligned.h>
23 
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "led.h"
27 #include "mesh.h"
28 #include "wep.h"
29 #include "wpa.h"
30 #include "tkip.h"
31 #include "wme.h"
32 #include "rate.h"
33 
34 /*
35  * monitor mode reception
36  *
37  * This function cleans up the SKB, i.e. it removes all the stuff
38  * only useful for monitoring.
39  */
40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
41 					   struct sk_buff *skb)
42 {
43 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
44 		if (likely(skb->len > FCS_LEN))
45 			__pskb_trim(skb, skb->len - FCS_LEN);
46 		else {
47 			/* driver bug */
48 			WARN_ON(1);
49 			dev_kfree_skb(skb);
50 			skb = NULL;
51 		}
52 	}
53 
54 	return skb;
55 }
56 
57 static inline int should_drop_frame(struct sk_buff *skb,
58 				    int present_fcs_len)
59 {
60 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
61 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
62 
63 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
64 		return 1;
65 	if (unlikely(skb->len < 16 + present_fcs_len))
66 		return 1;
67 	if (ieee80211_is_ctl(hdr->frame_control) &&
68 	    !ieee80211_is_pspoll(hdr->frame_control) &&
69 	    !ieee80211_is_back_req(hdr->frame_control))
70 		return 1;
71 	return 0;
72 }
73 
74 static int
75 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
76 			  struct ieee80211_rx_status *status)
77 {
78 	int len;
79 
80 	/* always present fields */
81 	len = sizeof(struct ieee80211_radiotap_header) + 9;
82 
83 	if (status->flag & RX_FLAG_MACTIME_MPDU)
84 		len += 8;
85 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
86 		len += 1;
87 
88 	if (len & 1) /* padding for RX_FLAGS if necessary */
89 		len++;
90 
91 	if (status->flag & RX_FLAG_HT) /* HT info */
92 		len += 3;
93 
94 	return len;
95 }
96 
97 /*
98  * ieee80211_add_rx_radiotap_header - add radiotap header
99  *
100  * add a radiotap header containing all the fields which the hardware provided.
101  */
102 static void
103 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
104 				 struct sk_buff *skb,
105 				 struct ieee80211_rate *rate,
106 				 int rtap_len, bool has_fcs)
107 {
108 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
109 	struct ieee80211_radiotap_header *rthdr;
110 	unsigned char *pos;
111 	u16 rx_flags = 0;
112 
113 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
114 	memset(rthdr, 0, rtap_len);
115 
116 	/* radiotap header, set always present flags */
117 	rthdr->it_present =
118 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
119 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
120 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
121 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
122 	rthdr->it_len = cpu_to_le16(rtap_len);
123 
124 	pos = (unsigned char *)(rthdr+1);
125 
126 	/* the order of the following fields is important */
127 
128 	/* IEEE80211_RADIOTAP_TSFT */
129 	if (status->flag & RX_FLAG_MACTIME_MPDU) {
130 		put_unaligned_le64(status->mactime, pos);
131 		rthdr->it_present |=
132 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
133 		pos += 8;
134 	}
135 
136 	/* IEEE80211_RADIOTAP_FLAGS */
137 	if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
138 		*pos |= IEEE80211_RADIOTAP_F_FCS;
139 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
140 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
141 	if (status->flag & RX_FLAG_SHORTPRE)
142 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
143 	pos++;
144 
145 	/* IEEE80211_RADIOTAP_RATE */
146 	if (!rate || status->flag & RX_FLAG_HT) {
147 		/*
148 		 * Without rate information don't add it. If we have,
149 		 * MCS information is a separate field in radiotap,
150 		 * added below. The byte here is needed as padding
151 		 * for the channel though, so initialise it to 0.
152 		 */
153 		*pos = 0;
154 	} else {
155 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
156 		*pos = rate->bitrate / 5;
157 	}
158 	pos++;
159 
160 	/* IEEE80211_RADIOTAP_CHANNEL */
161 	put_unaligned_le16(status->freq, pos);
162 	pos += 2;
163 	if (status->band == IEEE80211_BAND_5GHZ)
164 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
165 				   pos);
166 	else if (status->flag & RX_FLAG_HT)
167 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
168 				   pos);
169 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
170 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
171 				   pos);
172 	else if (rate)
173 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
174 				   pos);
175 	else
176 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
177 	pos += 2;
178 
179 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
180 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
181 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
182 		*pos = status->signal;
183 		rthdr->it_present |=
184 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
185 		pos++;
186 	}
187 
188 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
189 
190 	/* IEEE80211_RADIOTAP_ANTENNA */
191 	*pos = status->antenna;
192 	pos++;
193 
194 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
195 
196 	/* IEEE80211_RADIOTAP_RX_FLAGS */
197 	/* ensure 2 byte alignment for the 2 byte field as required */
198 	if ((pos - (u8 *)rthdr) & 1)
199 		pos++;
200 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
201 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
202 	put_unaligned_le16(rx_flags, pos);
203 	pos += 2;
204 
205 	if (status->flag & RX_FLAG_HT) {
206 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
207 		*pos++ = local->hw.radiotap_mcs_details;
208 		*pos = 0;
209 		if (status->flag & RX_FLAG_SHORT_GI)
210 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
211 		if (status->flag & RX_FLAG_40MHZ)
212 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
213 		if (status->flag & RX_FLAG_HT_GF)
214 			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
215 		pos++;
216 		*pos++ = status->rate_idx;
217 	}
218 }
219 
220 /*
221  * This function copies a received frame to all monitor interfaces and
222  * returns a cleaned-up SKB that no longer includes the FCS nor the
223  * radiotap header the driver might have added.
224  */
225 static struct sk_buff *
226 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
227 		     struct ieee80211_rate *rate)
228 {
229 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
230 	struct ieee80211_sub_if_data *sdata;
231 	int needed_headroom;
232 	struct sk_buff *skb, *skb2;
233 	struct net_device *prev_dev = NULL;
234 	int present_fcs_len = 0;
235 
236 	/*
237 	 * First, we may need to make a copy of the skb because
238 	 *  (1) we need to modify it for radiotap (if not present), and
239 	 *  (2) the other RX handlers will modify the skb we got.
240 	 *
241 	 * We don't need to, of course, if we aren't going to return
242 	 * the SKB because it has a bad FCS/PLCP checksum.
243 	 */
244 
245 	/* room for the radiotap header based on driver features */
246 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
247 
248 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
249 		present_fcs_len = FCS_LEN;
250 
251 	/* make sure hdr->frame_control is on the linear part */
252 	if (!pskb_may_pull(origskb, 2)) {
253 		dev_kfree_skb(origskb);
254 		return NULL;
255 	}
256 
257 	if (!local->monitors) {
258 		if (should_drop_frame(origskb, present_fcs_len)) {
259 			dev_kfree_skb(origskb);
260 			return NULL;
261 		}
262 
263 		return remove_monitor_info(local, origskb);
264 	}
265 
266 	if (should_drop_frame(origskb, present_fcs_len)) {
267 		/* only need to expand headroom if necessary */
268 		skb = origskb;
269 		origskb = NULL;
270 
271 		/*
272 		 * This shouldn't trigger often because most devices have an
273 		 * RX header they pull before we get here, and that should
274 		 * be big enough for our radiotap information. We should
275 		 * probably export the length to drivers so that we can have
276 		 * them allocate enough headroom to start with.
277 		 */
278 		if (skb_headroom(skb) < needed_headroom &&
279 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
280 			dev_kfree_skb(skb);
281 			return NULL;
282 		}
283 	} else {
284 		/*
285 		 * Need to make a copy and possibly remove radiotap header
286 		 * and FCS from the original.
287 		 */
288 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
289 
290 		origskb = remove_monitor_info(local, origskb);
291 
292 		if (!skb)
293 			return origskb;
294 	}
295 
296 	/* prepend radiotap information */
297 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
298 					 true);
299 
300 	skb_reset_mac_header(skb);
301 	skb->ip_summed = CHECKSUM_UNNECESSARY;
302 	skb->pkt_type = PACKET_OTHERHOST;
303 	skb->protocol = htons(ETH_P_802_2);
304 
305 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
306 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
307 			continue;
308 
309 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
310 			continue;
311 
312 		if (!ieee80211_sdata_running(sdata))
313 			continue;
314 
315 		if (prev_dev) {
316 			skb2 = skb_clone(skb, GFP_ATOMIC);
317 			if (skb2) {
318 				skb2->dev = prev_dev;
319 				netif_receive_skb(skb2);
320 			}
321 		}
322 
323 		prev_dev = sdata->dev;
324 		sdata->dev->stats.rx_packets++;
325 		sdata->dev->stats.rx_bytes += skb->len;
326 	}
327 
328 	if (prev_dev) {
329 		skb->dev = prev_dev;
330 		netif_receive_skb(skb);
331 	} else
332 		dev_kfree_skb(skb);
333 
334 	return origskb;
335 }
336 
337 
338 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
339 {
340 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
341 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
342 	int tid, seqno_idx, security_idx;
343 
344 	/* does the frame have a qos control field? */
345 	if (ieee80211_is_data_qos(hdr->frame_control)) {
346 		u8 *qc = ieee80211_get_qos_ctl(hdr);
347 		/* frame has qos control */
348 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
349 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
350 			status->rx_flags |= IEEE80211_RX_AMSDU;
351 
352 		seqno_idx = tid;
353 		security_idx = tid;
354 	} else {
355 		/*
356 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
357 		 *
358 		 *	Sequence numbers for management frames, QoS data
359 		 *	frames with a broadcast/multicast address in the
360 		 *	Address 1 field, and all non-QoS data frames sent
361 		 *	by QoS STAs are assigned using an additional single
362 		 *	modulo-4096 counter, [...]
363 		 *
364 		 * We also use that counter for non-QoS STAs.
365 		 */
366 		seqno_idx = NUM_RX_DATA_QUEUES;
367 		security_idx = 0;
368 		if (ieee80211_is_mgmt(hdr->frame_control))
369 			security_idx = NUM_RX_DATA_QUEUES;
370 		tid = 0;
371 	}
372 
373 	rx->seqno_idx = seqno_idx;
374 	rx->security_idx = security_idx;
375 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
376 	 * For now, set skb->priority to 0 for other cases. */
377 	rx->skb->priority = (tid > 7) ? 0 : tid;
378 }
379 
380 /**
381  * DOC: Packet alignment
382  *
383  * Drivers always need to pass packets that are aligned to two-byte boundaries
384  * to the stack.
385  *
386  * Additionally, should, if possible, align the payload data in a way that
387  * guarantees that the contained IP header is aligned to a four-byte
388  * boundary. In the case of regular frames, this simply means aligning the
389  * payload to a four-byte boundary (because either the IP header is directly
390  * contained, or IV/RFC1042 headers that have a length divisible by four are
391  * in front of it).  If the payload data is not properly aligned and the
392  * architecture doesn't support efficient unaligned operations, mac80211
393  * will align the data.
394  *
395  * With A-MSDU frames, however, the payload data address must yield two modulo
396  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
397  * push the IP header further back to a multiple of four again. Thankfully, the
398  * specs were sane enough this time around to require padding each A-MSDU
399  * subframe to a length that is a multiple of four.
400  *
401  * Padding like Atheros hardware adds which is between the 802.11 header and
402  * the payload is not supported, the driver is required to move the 802.11
403  * header to be directly in front of the payload in that case.
404  */
405 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
406 {
407 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
408 	WARN_ONCE((unsigned long)rx->skb->data & 1,
409 		  "unaligned packet at 0x%p\n", rx->skb->data);
410 #endif
411 }
412 
413 
414 /* rx handlers */
415 
416 static ieee80211_rx_result debug_noinline
417 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
418 {
419 	struct ieee80211_local *local = rx->local;
420 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
421 	struct sk_buff *skb = rx->skb;
422 
423 	if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
424 		   !local->sched_scanning))
425 		return RX_CONTINUE;
426 
427 	if (test_bit(SCAN_HW_SCANNING, &local->scanning) ||
428 	    test_bit(SCAN_SW_SCANNING, &local->scanning) ||
429 	    test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning) ||
430 	    local->sched_scanning)
431 		return ieee80211_scan_rx(rx->sdata, skb);
432 
433 	/* scanning finished during invoking of handlers */
434 	I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
435 	return RX_DROP_UNUSABLE;
436 }
437 
438 
439 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
440 {
441 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
442 
443 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
444 		return 0;
445 
446 	return ieee80211_is_robust_mgmt_frame(hdr);
447 }
448 
449 
450 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
451 {
452 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
453 
454 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
455 		return 0;
456 
457 	return ieee80211_is_robust_mgmt_frame(hdr);
458 }
459 
460 
461 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
462 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
463 {
464 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
465 	struct ieee80211_mmie *mmie;
466 
467 	if (skb->len < 24 + sizeof(*mmie) ||
468 	    !is_multicast_ether_addr(hdr->da))
469 		return -1;
470 
471 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
472 		return -1; /* not a robust management frame */
473 
474 	mmie = (struct ieee80211_mmie *)
475 		(skb->data + skb->len - sizeof(*mmie));
476 	if (mmie->element_id != WLAN_EID_MMIE ||
477 	    mmie->length != sizeof(*mmie) - 2)
478 		return -1;
479 
480 	return le16_to_cpu(mmie->key_id);
481 }
482 
483 
484 static ieee80211_rx_result
485 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
486 {
487 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
488 	char *dev_addr = rx->sdata->vif.addr;
489 
490 	if (ieee80211_is_data(hdr->frame_control)) {
491 		if (is_multicast_ether_addr(hdr->addr1)) {
492 			if (ieee80211_has_tods(hdr->frame_control) ||
493 				!ieee80211_has_fromds(hdr->frame_control))
494 				return RX_DROP_MONITOR;
495 			if (ether_addr_equal(hdr->addr3, dev_addr))
496 				return RX_DROP_MONITOR;
497 		} else {
498 			if (!ieee80211_has_a4(hdr->frame_control))
499 				return RX_DROP_MONITOR;
500 			if (ether_addr_equal(hdr->addr4, dev_addr))
501 				return RX_DROP_MONITOR;
502 		}
503 	}
504 
505 	/* If there is not an established peer link and this is not a peer link
506 	 * establisment frame, beacon or probe, drop the frame.
507 	 */
508 
509 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
510 		struct ieee80211_mgmt *mgmt;
511 
512 		if (!ieee80211_is_mgmt(hdr->frame_control))
513 			return RX_DROP_MONITOR;
514 
515 		if (ieee80211_is_action(hdr->frame_control)) {
516 			u8 category;
517 			mgmt = (struct ieee80211_mgmt *)hdr;
518 			category = mgmt->u.action.category;
519 			if (category != WLAN_CATEGORY_MESH_ACTION &&
520 				category != WLAN_CATEGORY_SELF_PROTECTED)
521 				return RX_DROP_MONITOR;
522 			return RX_CONTINUE;
523 		}
524 
525 		if (ieee80211_is_probe_req(hdr->frame_control) ||
526 		    ieee80211_is_probe_resp(hdr->frame_control) ||
527 		    ieee80211_is_beacon(hdr->frame_control) ||
528 		    ieee80211_is_auth(hdr->frame_control))
529 			return RX_CONTINUE;
530 
531 		return RX_DROP_MONITOR;
532 
533 	}
534 
535 	return RX_CONTINUE;
536 }
537 
538 #define SEQ_MODULO 0x1000
539 #define SEQ_MASK   0xfff
540 
541 static inline int seq_less(u16 sq1, u16 sq2)
542 {
543 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
544 }
545 
546 static inline u16 seq_inc(u16 sq)
547 {
548 	return (sq + 1) & SEQ_MASK;
549 }
550 
551 static inline u16 seq_sub(u16 sq1, u16 sq2)
552 {
553 	return (sq1 - sq2) & SEQ_MASK;
554 }
555 
556 
557 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
558 					    struct tid_ampdu_rx *tid_agg_rx,
559 					    int index)
560 {
561 	struct ieee80211_local *local = hw_to_local(hw);
562 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
563 	struct ieee80211_rx_status *status;
564 
565 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
566 
567 	if (!skb)
568 		goto no_frame;
569 
570 	/* release the frame from the reorder ring buffer */
571 	tid_agg_rx->stored_mpdu_num--;
572 	tid_agg_rx->reorder_buf[index] = NULL;
573 	status = IEEE80211_SKB_RXCB(skb);
574 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
575 	skb_queue_tail(&local->rx_skb_queue, skb);
576 
577 no_frame:
578 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
579 }
580 
581 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
582 					     struct tid_ampdu_rx *tid_agg_rx,
583 					     u16 head_seq_num)
584 {
585 	int index;
586 
587 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
588 
589 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
590 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
591 							tid_agg_rx->buf_size;
592 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
593 	}
594 }
595 
596 /*
597  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
598  * the skb was added to the buffer longer than this time ago, the earlier
599  * frames that have not yet been received are assumed to be lost and the skb
600  * can be released for processing. This may also release other skb's from the
601  * reorder buffer if there are no additional gaps between the frames.
602  *
603  * Callers must hold tid_agg_rx->reorder_lock.
604  */
605 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
606 
607 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
608 					  struct tid_ampdu_rx *tid_agg_rx)
609 {
610 	int index, j;
611 
612 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
613 
614 	/* release the buffer until next missing frame */
615 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
616 						tid_agg_rx->buf_size;
617 	if (!tid_agg_rx->reorder_buf[index] &&
618 	    tid_agg_rx->stored_mpdu_num) {
619 		/*
620 		 * No buffers ready to be released, but check whether any
621 		 * frames in the reorder buffer have timed out.
622 		 */
623 		int skipped = 1;
624 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
625 		     j = (j + 1) % tid_agg_rx->buf_size) {
626 			if (!tid_agg_rx->reorder_buf[j]) {
627 				skipped++;
628 				continue;
629 			}
630 			if (skipped &&
631 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
632 					HT_RX_REORDER_BUF_TIMEOUT))
633 				goto set_release_timer;
634 
635 #ifdef CONFIG_MAC80211_HT_DEBUG
636 			if (net_ratelimit())
637 				wiphy_debug(hw->wiphy,
638 					    "release an RX reorder frame due to timeout on earlier frames\n");
639 #endif
640 			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
641 
642 			/*
643 			 * Increment the head seq# also for the skipped slots.
644 			 */
645 			tid_agg_rx->head_seq_num =
646 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
647 			skipped = 0;
648 		}
649 	} else while (tid_agg_rx->reorder_buf[index]) {
650 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
651 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
652 							tid_agg_rx->buf_size;
653 	}
654 
655 	if (tid_agg_rx->stored_mpdu_num) {
656 		j = index = seq_sub(tid_agg_rx->head_seq_num,
657 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
658 
659 		for (; j != (index - 1) % tid_agg_rx->buf_size;
660 		     j = (j + 1) % tid_agg_rx->buf_size) {
661 			if (tid_agg_rx->reorder_buf[j])
662 				break;
663 		}
664 
665  set_release_timer:
666 
667 		mod_timer(&tid_agg_rx->reorder_timer,
668 			  tid_agg_rx->reorder_time[j] + 1 +
669 			  HT_RX_REORDER_BUF_TIMEOUT);
670 	} else {
671 		del_timer(&tid_agg_rx->reorder_timer);
672 	}
673 }
674 
675 /*
676  * As this function belongs to the RX path it must be under
677  * rcu_read_lock protection. It returns false if the frame
678  * can be processed immediately, true if it was consumed.
679  */
680 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
681 					     struct tid_ampdu_rx *tid_agg_rx,
682 					     struct sk_buff *skb)
683 {
684 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
685 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
686 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
687 	u16 head_seq_num, buf_size;
688 	int index;
689 	bool ret = true;
690 
691 	spin_lock(&tid_agg_rx->reorder_lock);
692 
693 	buf_size = tid_agg_rx->buf_size;
694 	head_seq_num = tid_agg_rx->head_seq_num;
695 
696 	/* frame with out of date sequence number */
697 	if (seq_less(mpdu_seq_num, head_seq_num)) {
698 		dev_kfree_skb(skb);
699 		goto out;
700 	}
701 
702 	/*
703 	 * If frame the sequence number exceeds our buffering window
704 	 * size release some previous frames to make room for this one.
705 	 */
706 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
707 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
708 		/* release stored frames up to new head to stack */
709 		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
710 	}
711 
712 	/* Now the new frame is always in the range of the reordering buffer */
713 
714 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
715 
716 	/* check if we already stored this frame */
717 	if (tid_agg_rx->reorder_buf[index]) {
718 		dev_kfree_skb(skb);
719 		goto out;
720 	}
721 
722 	/*
723 	 * If the current MPDU is in the right order and nothing else
724 	 * is stored we can process it directly, no need to buffer it.
725 	 * If it is first but there's something stored, we may be able
726 	 * to release frames after this one.
727 	 */
728 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
729 	    tid_agg_rx->stored_mpdu_num == 0) {
730 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
731 		ret = false;
732 		goto out;
733 	}
734 
735 	/* put the frame in the reordering buffer */
736 	tid_agg_rx->reorder_buf[index] = skb;
737 	tid_agg_rx->reorder_time[index] = jiffies;
738 	tid_agg_rx->stored_mpdu_num++;
739 	ieee80211_sta_reorder_release(hw, tid_agg_rx);
740 
741  out:
742 	spin_unlock(&tid_agg_rx->reorder_lock);
743 	return ret;
744 }
745 
746 /*
747  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
748  * true if the MPDU was buffered, false if it should be processed.
749  */
750 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
751 {
752 	struct sk_buff *skb = rx->skb;
753 	struct ieee80211_local *local = rx->local;
754 	struct ieee80211_hw *hw = &local->hw;
755 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
756 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
757 	struct sta_info *sta = rx->sta;
758 	struct tid_ampdu_rx *tid_agg_rx;
759 	u16 sc;
760 	u8 tid, ack_policy;
761 
762 	if (!ieee80211_is_data_qos(hdr->frame_control))
763 		goto dont_reorder;
764 
765 	/*
766 	 * filter the QoS data rx stream according to
767 	 * STA/TID and check if this STA/TID is on aggregation
768 	 */
769 
770 	if (!sta)
771 		goto dont_reorder;
772 
773 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
774 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
775 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
776 
777 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
778 	if (!tid_agg_rx)
779 		goto dont_reorder;
780 
781 	/* qos null data frames are excluded */
782 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
783 		goto dont_reorder;
784 
785 	/* not part of a BA session */
786 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
787 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
788 		goto dont_reorder;
789 
790 	/* not actually part of this BA session */
791 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
792 		goto dont_reorder;
793 
794 	/* new, potentially un-ordered, ampdu frame - process it */
795 
796 	/* reset session timer */
797 	if (tid_agg_rx->timeout)
798 		tid_agg_rx->last_rx = jiffies;
799 
800 	/* if this mpdu is fragmented - terminate rx aggregation session */
801 	sc = le16_to_cpu(hdr->seq_ctrl);
802 	if (sc & IEEE80211_SCTL_FRAG) {
803 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
804 		skb_queue_tail(&rx->sdata->skb_queue, skb);
805 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
806 		return;
807 	}
808 
809 	/*
810 	 * No locking needed -- we will only ever process one
811 	 * RX packet at a time, and thus own tid_agg_rx. All
812 	 * other code manipulating it needs to (and does) make
813 	 * sure that we cannot get to it any more before doing
814 	 * anything with it.
815 	 */
816 	if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
817 		return;
818 
819  dont_reorder:
820 	skb_queue_tail(&local->rx_skb_queue, skb);
821 }
822 
823 static ieee80211_rx_result debug_noinline
824 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
825 {
826 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
827 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
828 
829 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
830 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
831 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
832 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
833 			     hdr->seq_ctrl)) {
834 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
835 				rx->local->dot11FrameDuplicateCount++;
836 				rx->sta->num_duplicates++;
837 			}
838 			return RX_DROP_UNUSABLE;
839 		} else
840 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
841 	}
842 
843 	if (unlikely(rx->skb->len < 16)) {
844 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
845 		return RX_DROP_MONITOR;
846 	}
847 
848 	/* Drop disallowed frame classes based on STA auth/assoc state;
849 	 * IEEE 802.11, Chap 5.5.
850 	 *
851 	 * mac80211 filters only based on association state, i.e. it drops
852 	 * Class 3 frames from not associated stations. hostapd sends
853 	 * deauth/disassoc frames when needed. In addition, hostapd is
854 	 * responsible for filtering on both auth and assoc states.
855 	 */
856 
857 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
858 		return ieee80211_rx_mesh_check(rx);
859 
860 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
861 		      ieee80211_is_pspoll(hdr->frame_control)) &&
862 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
863 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
864 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
865 		/*
866 		 * accept port control frames from the AP even when it's not
867 		 * yet marked ASSOC to prevent a race where we don't set the
868 		 * assoc bit quickly enough before it sends the first frame
869 		 */
870 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
871 		    ieee80211_is_data_present(hdr->frame_control)) {
872 			u16 ethertype;
873 			u8 *payload;
874 
875 			payload = rx->skb->data +
876 				ieee80211_hdrlen(hdr->frame_control);
877 			ethertype = (payload[6] << 8) | payload[7];
878 			if (cpu_to_be16(ethertype) ==
879 			    rx->sdata->control_port_protocol)
880 				return RX_CONTINUE;
881 		}
882 
883 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
884 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
885 					       hdr->addr2,
886 					       GFP_ATOMIC))
887 			return RX_DROP_UNUSABLE;
888 
889 		return RX_DROP_MONITOR;
890 	}
891 
892 	return RX_CONTINUE;
893 }
894 
895 
896 static ieee80211_rx_result debug_noinline
897 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
898 {
899 	struct sk_buff *skb = rx->skb;
900 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
901 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
902 	int keyidx;
903 	int hdrlen;
904 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
905 	struct ieee80211_key *sta_ptk = NULL;
906 	int mmie_keyidx = -1;
907 	__le16 fc;
908 
909 	/*
910 	 * Key selection 101
911 	 *
912 	 * There are four types of keys:
913 	 *  - GTK (group keys)
914 	 *  - IGTK (group keys for management frames)
915 	 *  - PTK (pairwise keys)
916 	 *  - STK (station-to-station pairwise keys)
917 	 *
918 	 * When selecting a key, we have to distinguish between multicast
919 	 * (including broadcast) and unicast frames, the latter can only
920 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
921 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
922 	 * unicast frames can also use key indices like GTKs. Hence, if we
923 	 * don't have a PTK/STK we check the key index for a WEP key.
924 	 *
925 	 * Note that in a regular BSS, multicast frames are sent by the
926 	 * AP only, associated stations unicast the frame to the AP first
927 	 * which then multicasts it on their behalf.
928 	 *
929 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
930 	 * with each station, that is something we don't currently handle.
931 	 * The spec seems to expect that one negotiates the same key with
932 	 * every station but there's no such requirement; VLANs could be
933 	 * possible.
934 	 */
935 
936 	/*
937 	 * No point in finding a key and decrypting if the frame is neither
938 	 * addressed to us nor a multicast frame.
939 	 */
940 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
941 		return RX_CONTINUE;
942 
943 	/* start without a key */
944 	rx->key = NULL;
945 
946 	if (rx->sta)
947 		sta_ptk = rcu_dereference(rx->sta->ptk);
948 
949 	fc = hdr->frame_control;
950 
951 	if (!ieee80211_has_protected(fc))
952 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
953 
954 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
955 		rx->key = sta_ptk;
956 		if ((status->flag & RX_FLAG_DECRYPTED) &&
957 		    (status->flag & RX_FLAG_IV_STRIPPED))
958 			return RX_CONTINUE;
959 		/* Skip decryption if the frame is not protected. */
960 		if (!ieee80211_has_protected(fc))
961 			return RX_CONTINUE;
962 	} else if (mmie_keyidx >= 0) {
963 		/* Broadcast/multicast robust management frame / BIP */
964 		if ((status->flag & RX_FLAG_DECRYPTED) &&
965 		    (status->flag & RX_FLAG_IV_STRIPPED))
966 			return RX_CONTINUE;
967 
968 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
969 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
970 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
971 		if (rx->sta)
972 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
973 		if (!rx->key)
974 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
975 	} else if (!ieee80211_has_protected(fc)) {
976 		/*
977 		 * The frame was not protected, so skip decryption. However, we
978 		 * need to set rx->key if there is a key that could have been
979 		 * used so that the frame may be dropped if encryption would
980 		 * have been expected.
981 		 */
982 		struct ieee80211_key *key = NULL;
983 		struct ieee80211_sub_if_data *sdata = rx->sdata;
984 		int i;
985 
986 		if (ieee80211_is_mgmt(fc) &&
987 		    is_multicast_ether_addr(hdr->addr1) &&
988 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
989 			rx->key = key;
990 		else {
991 			if (rx->sta) {
992 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
993 					key = rcu_dereference(rx->sta->gtk[i]);
994 					if (key)
995 						break;
996 				}
997 			}
998 			if (!key) {
999 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1000 					key = rcu_dereference(sdata->keys[i]);
1001 					if (key)
1002 						break;
1003 				}
1004 			}
1005 			if (key)
1006 				rx->key = key;
1007 		}
1008 		return RX_CONTINUE;
1009 	} else {
1010 		u8 keyid;
1011 		/*
1012 		 * The device doesn't give us the IV so we won't be
1013 		 * able to look up the key. That's ok though, we
1014 		 * don't need to decrypt the frame, we just won't
1015 		 * be able to keep statistics accurate.
1016 		 * Except for key threshold notifications, should
1017 		 * we somehow allow the driver to tell us which key
1018 		 * the hardware used if this flag is set?
1019 		 */
1020 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1021 		    (status->flag & RX_FLAG_IV_STRIPPED))
1022 			return RX_CONTINUE;
1023 
1024 		hdrlen = ieee80211_hdrlen(fc);
1025 
1026 		if (rx->skb->len < 8 + hdrlen)
1027 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1028 
1029 		/*
1030 		 * no need to call ieee80211_wep_get_keyidx,
1031 		 * it verifies a bunch of things we've done already
1032 		 */
1033 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1034 		keyidx = keyid >> 6;
1035 
1036 		/* check per-station GTK first, if multicast packet */
1037 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1038 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1039 
1040 		/* if not found, try default key */
1041 		if (!rx->key) {
1042 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1043 
1044 			/*
1045 			 * RSNA-protected unicast frames should always be
1046 			 * sent with pairwise or station-to-station keys,
1047 			 * but for WEP we allow using a key index as well.
1048 			 */
1049 			if (rx->key &&
1050 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1051 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1052 			    !is_multicast_ether_addr(hdr->addr1))
1053 				rx->key = NULL;
1054 		}
1055 	}
1056 
1057 	if (rx->key) {
1058 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1059 			return RX_DROP_MONITOR;
1060 
1061 		rx->key->tx_rx_count++;
1062 		/* TODO: add threshold stuff again */
1063 	} else {
1064 		return RX_DROP_MONITOR;
1065 	}
1066 
1067 	switch (rx->key->conf.cipher) {
1068 	case WLAN_CIPHER_SUITE_WEP40:
1069 	case WLAN_CIPHER_SUITE_WEP104:
1070 		result = ieee80211_crypto_wep_decrypt(rx);
1071 		break;
1072 	case WLAN_CIPHER_SUITE_TKIP:
1073 		result = ieee80211_crypto_tkip_decrypt(rx);
1074 		break;
1075 	case WLAN_CIPHER_SUITE_CCMP:
1076 		result = ieee80211_crypto_ccmp_decrypt(rx);
1077 		break;
1078 	case WLAN_CIPHER_SUITE_AES_CMAC:
1079 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1080 		break;
1081 	default:
1082 		/*
1083 		 * We can reach here only with HW-only algorithms
1084 		 * but why didn't it decrypt the frame?!
1085 		 */
1086 		return RX_DROP_UNUSABLE;
1087 	}
1088 
1089 	/* the hdr variable is invalid after the decrypt handlers */
1090 
1091 	/* either the frame has been decrypted or will be dropped */
1092 	status->flag |= RX_FLAG_DECRYPTED;
1093 
1094 	return result;
1095 }
1096 
1097 static ieee80211_rx_result debug_noinline
1098 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1099 {
1100 	struct ieee80211_local *local;
1101 	struct ieee80211_hdr *hdr;
1102 	struct sk_buff *skb;
1103 
1104 	local = rx->local;
1105 	skb = rx->skb;
1106 	hdr = (struct ieee80211_hdr *) skb->data;
1107 
1108 	if (!local->pspolling)
1109 		return RX_CONTINUE;
1110 
1111 	if (!ieee80211_has_fromds(hdr->frame_control))
1112 		/* this is not from AP */
1113 		return RX_CONTINUE;
1114 
1115 	if (!ieee80211_is_data(hdr->frame_control))
1116 		return RX_CONTINUE;
1117 
1118 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1119 		/* AP has no more frames buffered for us */
1120 		local->pspolling = false;
1121 		return RX_CONTINUE;
1122 	}
1123 
1124 	/* more data bit is set, let's request a new frame from the AP */
1125 	ieee80211_send_pspoll(local, rx->sdata);
1126 
1127 	return RX_CONTINUE;
1128 }
1129 
1130 static void ap_sta_ps_start(struct sta_info *sta)
1131 {
1132 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1133 	struct ieee80211_local *local = sdata->local;
1134 
1135 	atomic_inc(&sdata->bss->num_sta_ps);
1136 	set_sta_flag(sta, WLAN_STA_PS_STA);
1137 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1138 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1139 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1140 	printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1141 	       sdata->name, sta->sta.addr, sta->sta.aid);
1142 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1143 }
1144 
1145 static void ap_sta_ps_end(struct sta_info *sta)
1146 {
1147 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1148 	printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1149 	       sta->sdata->name, sta->sta.addr, sta->sta.aid);
1150 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1151 
1152 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1153 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1154 		printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1155 		       sta->sdata->name, sta->sta.addr, sta->sta.aid);
1156 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1157 		return;
1158 	}
1159 
1160 	ieee80211_sta_ps_deliver_wakeup(sta);
1161 }
1162 
1163 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1164 {
1165 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1166 	bool in_ps;
1167 
1168 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1169 
1170 	/* Don't let the same PS state be set twice */
1171 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1172 	if ((start && in_ps) || (!start && !in_ps))
1173 		return -EINVAL;
1174 
1175 	if (start)
1176 		ap_sta_ps_start(sta_inf);
1177 	else
1178 		ap_sta_ps_end(sta_inf);
1179 
1180 	return 0;
1181 }
1182 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1183 
1184 static ieee80211_rx_result debug_noinline
1185 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1186 {
1187 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1188 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1189 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1190 	int tid, ac;
1191 
1192 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1193 		return RX_CONTINUE;
1194 
1195 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1196 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1197 		return RX_CONTINUE;
1198 
1199 	/*
1200 	 * The device handles station powersave, so don't do anything about
1201 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1202 	 * it to mac80211 since they're handled.)
1203 	 */
1204 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1205 		return RX_CONTINUE;
1206 
1207 	/*
1208 	 * Don't do anything if the station isn't already asleep. In
1209 	 * the uAPSD case, the station will probably be marked asleep,
1210 	 * in the PS-Poll case the station must be confused ...
1211 	 */
1212 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1213 		return RX_CONTINUE;
1214 
1215 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1216 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1217 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1218 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1219 			else
1220 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1221 		}
1222 
1223 		/* Free PS Poll skb here instead of returning RX_DROP that would
1224 		 * count as an dropped frame. */
1225 		dev_kfree_skb(rx->skb);
1226 
1227 		return RX_QUEUED;
1228 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1229 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1230 		   ieee80211_has_pm(hdr->frame_control) &&
1231 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1232 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1233 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1234 		ac = ieee802_1d_to_ac[tid & 7];
1235 
1236 		/*
1237 		 * If this AC is not trigger-enabled do nothing.
1238 		 *
1239 		 * NB: This could/should check a separate bitmap of trigger-
1240 		 * enabled queues, but for now we only implement uAPSD w/o
1241 		 * TSPEC changes to the ACs, so they're always the same.
1242 		 */
1243 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1244 			return RX_CONTINUE;
1245 
1246 		/* if we are in a service period, do nothing */
1247 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1248 			return RX_CONTINUE;
1249 
1250 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1251 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1252 		else
1253 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1254 	}
1255 
1256 	return RX_CONTINUE;
1257 }
1258 
1259 static ieee80211_rx_result debug_noinline
1260 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1261 {
1262 	struct sta_info *sta = rx->sta;
1263 	struct sk_buff *skb = rx->skb;
1264 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1265 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1266 
1267 	if (!sta)
1268 		return RX_CONTINUE;
1269 
1270 	/*
1271 	 * Update last_rx only for IBSS packets which are for the current
1272 	 * BSSID to avoid keeping the current IBSS network alive in cases
1273 	 * where other STAs start using different BSSID.
1274 	 */
1275 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1276 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1277 						NL80211_IFTYPE_ADHOC);
1278 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid)) {
1279 			sta->last_rx = jiffies;
1280 			if (ieee80211_is_data(hdr->frame_control)) {
1281 				sta->last_rx_rate_idx = status->rate_idx;
1282 				sta->last_rx_rate_flag = status->flag;
1283 			}
1284 		}
1285 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1286 		/*
1287 		 * Mesh beacons will update last_rx when if they are found to
1288 		 * match the current local configuration when processed.
1289 		 */
1290 		sta->last_rx = jiffies;
1291 		if (ieee80211_is_data(hdr->frame_control)) {
1292 			sta->last_rx_rate_idx = status->rate_idx;
1293 			sta->last_rx_rate_flag = status->flag;
1294 		}
1295 	}
1296 
1297 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1298 		return RX_CONTINUE;
1299 
1300 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1301 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1302 
1303 	sta->rx_fragments++;
1304 	sta->rx_bytes += rx->skb->len;
1305 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1306 		sta->last_signal = status->signal;
1307 		ewma_add(&sta->avg_signal, -status->signal);
1308 	}
1309 
1310 	/*
1311 	 * Change STA power saving mode only at the end of a frame
1312 	 * exchange sequence.
1313 	 */
1314 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1315 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1316 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1317 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1318 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1319 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1320 			/*
1321 			 * Ignore doze->wake transitions that are
1322 			 * indicated by non-data frames, the standard
1323 			 * is unclear here, but for example going to
1324 			 * PS mode and then scanning would cause a
1325 			 * doze->wake transition for the probe request,
1326 			 * and that is clearly undesirable.
1327 			 */
1328 			if (ieee80211_is_data(hdr->frame_control) &&
1329 			    !ieee80211_has_pm(hdr->frame_control))
1330 				ap_sta_ps_end(sta);
1331 		} else {
1332 			if (ieee80211_has_pm(hdr->frame_control))
1333 				ap_sta_ps_start(sta);
1334 		}
1335 	}
1336 
1337 	/*
1338 	 * Drop (qos-)data::nullfunc frames silently, since they
1339 	 * are used only to control station power saving mode.
1340 	 */
1341 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1342 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1343 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1344 
1345 		/*
1346 		 * If we receive a 4-addr nullfunc frame from a STA
1347 		 * that was not moved to a 4-addr STA vlan yet send
1348 		 * the event to userspace and for older hostapd drop
1349 		 * the frame to the monitor interface.
1350 		 */
1351 		if (ieee80211_has_a4(hdr->frame_control) &&
1352 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1353 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1354 		      !rx->sdata->u.vlan.sta))) {
1355 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1356 				cfg80211_rx_unexpected_4addr_frame(
1357 					rx->sdata->dev, sta->sta.addr,
1358 					GFP_ATOMIC);
1359 			return RX_DROP_MONITOR;
1360 		}
1361 		/*
1362 		 * Update counter and free packet here to avoid
1363 		 * counting this as a dropped packed.
1364 		 */
1365 		sta->rx_packets++;
1366 		dev_kfree_skb(rx->skb);
1367 		return RX_QUEUED;
1368 	}
1369 
1370 	return RX_CONTINUE;
1371 } /* ieee80211_rx_h_sta_process */
1372 
1373 static inline struct ieee80211_fragment_entry *
1374 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1375 			 unsigned int frag, unsigned int seq, int rx_queue,
1376 			 struct sk_buff **skb)
1377 {
1378 	struct ieee80211_fragment_entry *entry;
1379 	int idx;
1380 
1381 	idx = sdata->fragment_next;
1382 	entry = &sdata->fragments[sdata->fragment_next++];
1383 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1384 		sdata->fragment_next = 0;
1385 
1386 	if (!skb_queue_empty(&entry->skb_list)) {
1387 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1388 		struct ieee80211_hdr *hdr =
1389 			(struct ieee80211_hdr *) entry->skb_list.next->data;
1390 		printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1391 		       "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1392 		       "addr1=%pM addr2=%pM\n",
1393 		       sdata->name, idx,
1394 		       jiffies - entry->first_frag_time, entry->seq,
1395 		       entry->last_frag, hdr->addr1, hdr->addr2);
1396 #endif
1397 		__skb_queue_purge(&entry->skb_list);
1398 	}
1399 
1400 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1401 	*skb = NULL;
1402 	entry->first_frag_time = jiffies;
1403 	entry->seq = seq;
1404 	entry->rx_queue = rx_queue;
1405 	entry->last_frag = frag;
1406 	entry->ccmp = 0;
1407 	entry->extra_len = 0;
1408 
1409 	return entry;
1410 }
1411 
1412 static inline struct ieee80211_fragment_entry *
1413 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1414 			  unsigned int frag, unsigned int seq,
1415 			  int rx_queue, struct ieee80211_hdr *hdr)
1416 {
1417 	struct ieee80211_fragment_entry *entry;
1418 	int i, idx;
1419 
1420 	idx = sdata->fragment_next;
1421 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1422 		struct ieee80211_hdr *f_hdr;
1423 
1424 		idx--;
1425 		if (idx < 0)
1426 			idx = IEEE80211_FRAGMENT_MAX - 1;
1427 
1428 		entry = &sdata->fragments[idx];
1429 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1430 		    entry->rx_queue != rx_queue ||
1431 		    entry->last_frag + 1 != frag)
1432 			continue;
1433 
1434 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1435 
1436 		/*
1437 		 * Check ftype and addresses are equal, else check next fragment
1438 		 */
1439 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1440 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1441 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1442 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1443 			continue;
1444 
1445 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1446 			__skb_queue_purge(&entry->skb_list);
1447 			continue;
1448 		}
1449 		return entry;
1450 	}
1451 
1452 	return NULL;
1453 }
1454 
1455 static ieee80211_rx_result debug_noinline
1456 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1457 {
1458 	struct ieee80211_hdr *hdr;
1459 	u16 sc;
1460 	__le16 fc;
1461 	unsigned int frag, seq;
1462 	struct ieee80211_fragment_entry *entry;
1463 	struct sk_buff *skb;
1464 	struct ieee80211_rx_status *status;
1465 
1466 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1467 	fc = hdr->frame_control;
1468 	sc = le16_to_cpu(hdr->seq_ctrl);
1469 	frag = sc & IEEE80211_SCTL_FRAG;
1470 
1471 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1472 		   (rx->skb)->len < 24 ||
1473 		   is_multicast_ether_addr(hdr->addr1))) {
1474 		/* not fragmented */
1475 		goto out;
1476 	}
1477 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1478 
1479 	if (skb_linearize(rx->skb))
1480 		return RX_DROP_UNUSABLE;
1481 
1482 	/*
1483 	 *  skb_linearize() might change the skb->data and
1484 	 *  previously cached variables (in this case, hdr) need to
1485 	 *  be refreshed with the new data.
1486 	 */
1487 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1488 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1489 
1490 	if (frag == 0) {
1491 		/* This is the first fragment of a new frame. */
1492 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1493 						 rx->seqno_idx, &(rx->skb));
1494 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1495 		    ieee80211_has_protected(fc)) {
1496 			int queue = rx->security_idx;
1497 			/* Store CCMP PN so that we can verify that the next
1498 			 * fragment has a sequential PN value. */
1499 			entry->ccmp = 1;
1500 			memcpy(entry->last_pn,
1501 			       rx->key->u.ccmp.rx_pn[queue],
1502 			       CCMP_PN_LEN);
1503 		}
1504 		return RX_QUEUED;
1505 	}
1506 
1507 	/* This is a fragment for a frame that should already be pending in
1508 	 * fragment cache. Add this fragment to the end of the pending entry.
1509 	 */
1510 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1511 					  rx->seqno_idx, hdr);
1512 	if (!entry) {
1513 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1514 		return RX_DROP_MONITOR;
1515 	}
1516 
1517 	/* Verify that MPDUs within one MSDU have sequential PN values.
1518 	 * (IEEE 802.11i, 8.3.3.4.5) */
1519 	if (entry->ccmp) {
1520 		int i;
1521 		u8 pn[CCMP_PN_LEN], *rpn;
1522 		int queue;
1523 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1524 			return RX_DROP_UNUSABLE;
1525 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1526 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1527 			pn[i]++;
1528 			if (pn[i])
1529 				break;
1530 		}
1531 		queue = rx->security_idx;
1532 		rpn = rx->key->u.ccmp.rx_pn[queue];
1533 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1534 			return RX_DROP_UNUSABLE;
1535 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1536 	}
1537 
1538 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1539 	__skb_queue_tail(&entry->skb_list, rx->skb);
1540 	entry->last_frag = frag;
1541 	entry->extra_len += rx->skb->len;
1542 	if (ieee80211_has_morefrags(fc)) {
1543 		rx->skb = NULL;
1544 		return RX_QUEUED;
1545 	}
1546 
1547 	rx->skb = __skb_dequeue(&entry->skb_list);
1548 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1549 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1550 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1551 					      GFP_ATOMIC))) {
1552 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1553 			__skb_queue_purge(&entry->skb_list);
1554 			return RX_DROP_UNUSABLE;
1555 		}
1556 	}
1557 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1558 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1559 		dev_kfree_skb(skb);
1560 	}
1561 
1562 	/* Complete frame has been reassembled - process it now */
1563 	status = IEEE80211_SKB_RXCB(rx->skb);
1564 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1565 
1566  out:
1567 	if (rx->sta)
1568 		rx->sta->rx_packets++;
1569 	if (is_multicast_ether_addr(hdr->addr1))
1570 		rx->local->dot11MulticastReceivedFrameCount++;
1571 	else
1572 		ieee80211_led_rx(rx->local);
1573 	return RX_CONTINUE;
1574 }
1575 
1576 static int
1577 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1578 {
1579 	if (unlikely(!rx->sta ||
1580 	    !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1581 		return -EACCES;
1582 
1583 	return 0;
1584 }
1585 
1586 static int
1587 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1588 {
1589 	struct sk_buff *skb = rx->skb;
1590 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1591 
1592 	/*
1593 	 * Pass through unencrypted frames if the hardware has
1594 	 * decrypted them already.
1595 	 */
1596 	if (status->flag & RX_FLAG_DECRYPTED)
1597 		return 0;
1598 
1599 	/* Drop unencrypted frames if key is set. */
1600 	if (unlikely(!ieee80211_has_protected(fc) &&
1601 		     !ieee80211_is_nullfunc(fc) &&
1602 		     ieee80211_is_data(fc) &&
1603 		     (rx->key || rx->sdata->drop_unencrypted)))
1604 		return -EACCES;
1605 
1606 	return 0;
1607 }
1608 
1609 static int
1610 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1611 {
1612 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1613 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1614 	__le16 fc = hdr->frame_control;
1615 
1616 	/*
1617 	 * Pass through unencrypted frames if the hardware has
1618 	 * decrypted them already.
1619 	 */
1620 	if (status->flag & RX_FLAG_DECRYPTED)
1621 		return 0;
1622 
1623 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1624 		if (unlikely(!ieee80211_has_protected(fc) &&
1625 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1626 			     rx->key)) {
1627 			if (ieee80211_is_deauth(fc))
1628 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1629 							    rx->skb->data,
1630 							    rx->skb->len);
1631 			else if (ieee80211_is_disassoc(fc))
1632 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1633 							      rx->skb->data,
1634 							      rx->skb->len);
1635 			return -EACCES;
1636 		}
1637 		/* BIP does not use Protected field, so need to check MMIE */
1638 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1639 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1640 			if (ieee80211_is_deauth(fc))
1641 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1642 							    rx->skb->data,
1643 							    rx->skb->len);
1644 			else if (ieee80211_is_disassoc(fc))
1645 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1646 							      rx->skb->data,
1647 							      rx->skb->len);
1648 			return -EACCES;
1649 		}
1650 		/*
1651 		 * When using MFP, Action frames are not allowed prior to
1652 		 * having configured keys.
1653 		 */
1654 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1655 			     ieee80211_is_robust_mgmt_frame(
1656 				     (struct ieee80211_hdr *) rx->skb->data)))
1657 			return -EACCES;
1658 	}
1659 
1660 	return 0;
1661 }
1662 
1663 static int
1664 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1665 {
1666 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1667 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1668 	bool check_port_control = false;
1669 	struct ethhdr *ehdr;
1670 	int ret;
1671 
1672 	*port_control = false;
1673 	if (ieee80211_has_a4(hdr->frame_control) &&
1674 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1675 		return -1;
1676 
1677 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1678 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1679 
1680 		if (!sdata->u.mgd.use_4addr)
1681 			return -1;
1682 		else
1683 			check_port_control = true;
1684 	}
1685 
1686 	if (is_multicast_ether_addr(hdr->addr1) &&
1687 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1688 		return -1;
1689 
1690 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1691 	if (ret < 0)
1692 		return ret;
1693 
1694 	ehdr = (struct ethhdr *) rx->skb->data;
1695 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1696 		*port_control = true;
1697 	else if (check_port_control)
1698 		return -1;
1699 
1700 	return 0;
1701 }
1702 
1703 /*
1704  * requires that rx->skb is a frame with ethernet header
1705  */
1706 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1707 {
1708 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1709 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1710 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1711 
1712 	/*
1713 	 * Allow EAPOL frames to us/the PAE group address regardless
1714 	 * of whether the frame was encrypted or not.
1715 	 */
1716 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1717 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1718 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1719 		return true;
1720 
1721 	if (ieee80211_802_1x_port_control(rx) ||
1722 	    ieee80211_drop_unencrypted(rx, fc))
1723 		return false;
1724 
1725 	return true;
1726 }
1727 
1728 /*
1729  * requires that rx->skb is a frame with ethernet header
1730  */
1731 static void
1732 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1733 {
1734 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1735 	struct net_device *dev = sdata->dev;
1736 	struct sk_buff *skb, *xmit_skb;
1737 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1738 	struct sta_info *dsta;
1739 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1740 
1741 	skb = rx->skb;
1742 	xmit_skb = NULL;
1743 
1744 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1745 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1746 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1747 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1748 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1749 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1750 			/*
1751 			 * send multicast frames both to higher layers in
1752 			 * local net stack and back to the wireless medium
1753 			 */
1754 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1755 			if (!xmit_skb)
1756 				net_dbg_ratelimited("%s: failed to clone multicast frame\n",
1757 						    dev->name);
1758 		} else {
1759 			dsta = sta_info_get(sdata, skb->data);
1760 			if (dsta) {
1761 				/*
1762 				 * The destination station is associated to
1763 				 * this AP (in this VLAN), so send the frame
1764 				 * directly to it and do not pass it to local
1765 				 * net stack.
1766 				 */
1767 				xmit_skb = skb;
1768 				skb = NULL;
1769 			}
1770 		}
1771 	}
1772 
1773 	if (skb) {
1774 		int align __maybe_unused;
1775 
1776 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1777 		/*
1778 		 * 'align' will only take the values 0 or 2 here
1779 		 * since all frames are required to be aligned
1780 		 * to 2-byte boundaries when being passed to
1781 		 * mac80211. That also explains the __skb_push()
1782 		 * below.
1783 		 */
1784 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1785 		if (align) {
1786 			if (WARN_ON(skb_headroom(skb) < 3)) {
1787 				dev_kfree_skb(skb);
1788 				skb = NULL;
1789 			} else {
1790 				u8 *data = skb->data;
1791 				size_t len = skb_headlen(skb);
1792 				skb->data -= align;
1793 				memmove(skb->data, data, len);
1794 				skb_set_tail_pointer(skb, len);
1795 			}
1796 		}
1797 #endif
1798 
1799 		if (skb) {
1800 			/* deliver to local stack */
1801 			skb->protocol = eth_type_trans(skb, dev);
1802 			memset(skb->cb, 0, sizeof(skb->cb));
1803 			netif_receive_skb(skb);
1804 		}
1805 	}
1806 
1807 	if (xmit_skb) {
1808 		/*
1809 		 * Send to wireless media and increase priority by 256 to
1810 		 * keep the received priority instead of reclassifying
1811 		 * the frame (see cfg80211_classify8021d).
1812 		 */
1813 		xmit_skb->priority += 256;
1814 		xmit_skb->protocol = htons(ETH_P_802_3);
1815 		skb_reset_network_header(xmit_skb);
1816 		skb_reset_mac_header(xmit_skb);
1817 		dev_queue_xmit(xmit_skb);
1818 	}
1819 }
1820 
1821 static ieee80211_rx_result debug_noinline
1822 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1823 {
1824 	struct net_device *dev = rx->sdata->dev;
1825 	struct sk_buff *skb = rx->skb;
1826 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1827 	__le16 fc = hdr->frame_control;
1828 	struct sk_buff_head frame_list;
1829 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1830 
1831 	if (unlikely(!ieee80211_is_data(fc)))
1832 		return RX_CONTINUE;
1833 
1834 	if (unlikely(!ieee80211_is_data_present(fc)))
1835 		return RX_DROP_MONITOR;
1836 
1837 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1838 		return RX_CONTINUE;
1839 
1840 	if (ieee80211_has_a4(hdr->frame_control) &&
1841 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1842 	    !rx->sdata->u.vlan.sta)
1843 		return RX_DROP_UNUSABLE;
1844 
1845 	if (is_multicast_ether_addr(hdr->addr1) &&
1846 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1847 	      rx->sdata->u.vlan.sta) ||
1848 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1849 	      rx->sdata->u.mgd.use_4addr)))
1850 		return RX_DROP_UNUSABLE;
1851 
1852 	skb->dev = dev;
1853 	__skb_queue_head_init(&frame_list);
1854 
1855 	if (skb_linearize(skb))
1856 		return RX_DROP_UNUSABLE;
1857 
1858 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1859 				 rx->sdata->vif.type,
1860 				 rx->local->hw.extra_tx_headroom, true);
1861 
1862 	while (!skb_queue_empty(&frame_list)) {
1863 		rx->skb = __skb_dequeue(&frame_list);
1864 
1865 		if (!ieee80211_frame_allowed(rx, fc)) {
1866 			dev_kfree_skb(rx->skb);
1867 			continue;
1868 		}
1869 		dev->stats.rx_packets++;
1870 		dev->stats.rx_bytes += rx->skb->len;
1871 
1872 		ieee80211_deliver_skb(rx);
1873 	}
1874 
1875 	return RX_QUEUED;
1876 }
1877 
1878 #ifdef CONFIG_MAC80211_MESH
1879 static ieee80211_rx_result
1880 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1881 {
1882 	struct ieee80211_hdr *fwd_hdr, *hdr;
1883 	struct ieee80211_tx_info *info;
1884 	struct ieee80211s_hdr *mesh_hdr;
1885 	struct sk_buff *skb = rx->skb, *fwd_skb;
1886 	struct ieee80211_local *local = rx->local;
1887 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1888 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1889 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1890 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1891 	u16 q, hdrlen;
1892 
1893 	hdr = (struct ieee80211_hdr *) skb->data;
1894 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1895 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1896 
1897 	/* frame is in RMC, don't forward */
1898 	if (ieee80211_is_data(hdr->frame_control) &&
1899 	    is_multicast_ether_addr(hdr->addr1) &&
1900 	    mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1901 		return RX_DROP_MONITOR;
1902 
1903 	if (!ieee80211_is_data(hdr->frame_control))
1904 		return RX_CONTINUE;
1905 
1906 	if (!mesh_hdr->ttl)
1907 		return RX_DROP_MONITOR;
1908 
1909 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
1910 		struct mesh_path *mppath;
1911 		char *proxied_addr;
1912 		char *mpp_addr;
1913 
1914 		if (is_multicast_ether_addr(hdr->addr1)) {
1915 			mpp_addr = hdr->addr3;
1916 			proxied_addr = mesh_hdr->eaddr1;
1917 		} else {
1918 			mpp_addr = hdr->addr4;
1919 			proxied_addr = mesh_hdr->eaddr2;
1920 		}
1921 
1922 		rcu_read_lock();
1923 		mppath = mpp_path_lookup(proxied_addr, sdata);
1924 		if (!mppath) {
1925 			mpp_path_add(proxied_addr, mpp_addr, sdata);
1926 		} else {
1927 			spin_lock_bh(&mppath->state_lock);
1928 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
1929 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1930 			spin_unlock_bh(&mppath->state_lock);
1931 		}
1932 		rcu_read_unlock();
1933 	}
1934 
1935 	/* Frame has reached destination.  Don't forward */
1936 	if (!is_multicast_ether_addr(hdr->addr1) &&
1937 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
1938 		return RX_CONTINUE;
1939 
1940 	q = ieee80211_select_queue_80211(local, skb, hdr);
1941 	if (ieee80211_queue_stopped(&local->hw, q)) {
1942 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1943 		return RX_DROP_MONITOR;
1944 	}
1945 	skb_set_queue_mapping(skb, q);
1946 
1947 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1948 		goto out;
1949 
1950 	if (!--mesh_hdr->ttl) {
1951 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1952 		return RX_DROP_MONITOR;
1953 	}
1954 
1955 	if (!ifmsh->mshcfg.dot11MeshForwarding)
1956 		goto out;
1957 
1958 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
1959 	if (!fwd_skb) {
1960 		net_dbg_ratelimited("%s: failed to clone mesh frame\n",
1961 				    sdata->name);
1962 		goto out;
1963 	}
1964 
1965 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1966 	info = IEEE80211_SKB_CB(fwd_skb);
1967 	memset(info, 0, sizeof(*info));
1968 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1969 	info->control.vif = &rx->sdata->vif;
1970 	info->control.jiffies = jiffies;
1971 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1972 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1973 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1974 	} else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1975 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1976 	} else {
1977 		/* unable to resolve next hop */
1978 		mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
1979 				    0, reason, fwd_hdr->addr2, sdata);
1980 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
1981 		kfree_skb(fwd_skb);
1982 		return RX_DROP_MONITOR;
1983 	}
1984 
1985 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
1986 	ieee80211_add_pending_skb(local, fwd_skb);
1987  out:
1988 	if (is_multicast_ether_addr(hdr->addr1) ||
1989 	    sdata->dev->flags & IFF_PROMISC)
1990 		return RX_CONTINUE;
1991 	else
1992 		return RX_DROP_MONITOR;
1993 }
1994 #endif
1995 
1996 static ieee80211_rx_result debug_noinline
1997 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1998 {
1999 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2000 	struct ieee80211_local *local = rx->local;
2001 	struct net_device *dev = sdata->dev;
2002 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2003 	__le16 fc = hdr->frame_control;
2004 	bool port_control;
2005 	int err;
2006 
2007 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2008 		return RX_CONTINUE;
2009 
2010 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2011 		return RX_DROP_MONITOR;
2012 
2013 	/*
2014 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2015 	 * also drop the frame to cooked monitor interfaces.
2016 	 */
2017 	if (ieee80211_has_a4(hdr->frame_control) &&
2018 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2019 		if (rx->sta &&
2020 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2021 			cfg80211_rx_unexpected_4addr_frame(
2022 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2023 		return RX_DROP_MONITOR;
2024 	}
2025 
2026 	err = __ieee80211_data_to_8023(rx, &port_control);
2027 	if (unlikely(err))
2028 		return RX_DROP_UNUSABLE;
2029 
2030 	if (!ieee80211_frame_allowed(rx, fc))
2031 		return RX_DROP_MONITOR;
2032 
2033 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2034 	    unlikely(port_control) && sdata->bss) {
2035 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2036 				     u.ap);
2037 		dev = sdata->dev;
2038 		rx->sdata = sdata;
2039 	}
2040 
2041 	rx->skb->dev = dev;
2042 
2043 	dev->stats.rx_packets++;
2044 	dev->stats.rx_bytes += rx->skb->len;
2045 
2046 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2047 	    !is_multicast_ether_addr(
2048 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2049 	    (!local->scanning &&
2050 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2051 			mod_timer(&local->dynamic_ps_timer, jiffies +
2052 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2053 	}
2054 
2055 	ieee80211_deliver_skb(rx);
2056 
2057 	return RX_QUEUED;
2058 }
2059 
2060 static ieee80211_rx_result debug_noinline
2061 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2062 {
2063 	struct ieee80211_local *local = rx->local;
2064 	struct ieee80211_hw *hw = &local->hw;
2065 	struct sk_buff *skb = rx->skb;
2066 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2067 	struct tid_ampdu_rx *tid_agg_rx;
2068 	u16 start_seq_num;
2069 	u16 tid;
2070 
2071 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2072 		return RX_CONTINUE;
2073 
2074 	if (ieee80211_is_back_req(bar->frame_control)) {
2075 		struct {
2076 			__le16 control, start_seq_num;
2077 		} __packed bar_data;
2078 
2079 		if (!rx->sta)
2080 			return RX_DROP_MONITOR;
2081 
2082 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2083 				  &bar_data, sizeof(bar_data)))
2084 			return RX_DROP_MONITOR;
2085 
2086 		tid = le16_to_cpu(bar_data.control) >> 12;
2087 
2088 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2089 		if (!tid_agg_rx)
2090 			return RX_DROP_MONITOR;
2091 
2092 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2093 
2094 		/* reset session timer */
2095 		if (tid_agg_rx->timeout)
2096 			mod_timer(&tid_agg_rx->session_timer,
2097 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2098 
2099 		spin_lock(&tid_agg_rx->reorder_lock);
2100 		/* release stored frames up to start of BAR */
2101 		ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
2102 		spin_unlock(&tid_agg_rx->reorder_lock);
2103 
2104 		kfree_skb(skb);
2105 		return RX_QUEUED;
2106 	}
2107 
2108 	/*
2109 	 * After this point, we only want management frames,
2110 	 * so we can drop all remaining control frames to
2111 	 * cooked monitor interfaces.
2112 	 */
2113 	return RX_DROP_MONITOR;
2114 }
2115 
2116 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2117 					   struct ieee80211_mgmt *mgmt,
2118 					   size_t len)
2119 {
2120 	struct ieee80211_local *local = sdata->local;
2121 	struct sk_buff *skb;
2122 	struct ieee80211_mgmt *resp;
2123 
2124 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2125 		/* Not to own unicast address */
2126 		return;
2127 	}
2128 
2129 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2130 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2131 		/* Not from the current AP or not associated yet. */
2132 		return;
2133 	}
2134 
2135 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2136 		/* Too short SA Query request frame */
2137 		return;
2138 	}
2139 
2140 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2141 	if (skb == NULL)
2142 		return;
2143 
2144 	skb_reserve(skb, local->hw.extra_tx_headroom);
2145 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2146 	memset(resp, 0, 24);
2147 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2148 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2149 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2150 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2151 					  IEEE80211_STYPE_ACTION);
2152 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2153 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2154 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2155 	memcpy(resp->u.action.u.sa_query.trans_id,
2156 	       mgmt->u.action.u.sa_query.trans_id,
2157 	       WLAN_SA_QUERY_TR_ID_LEN);
2158 
2159 	ieee80211_tx_skb(sdata, skb);
2160 }
2161 
2162 static ieee80211_rx_result debug_noinline
2163 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2164 {
2165 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2166 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2167 
2168 	/*
2169 	 * From here on, look only at management frames.
2170 	 * Data and control frames are already handled,
2171 	 * and unknown (reserved) frames are useless.
2172 	 */
2173 	if (rx->skb->len < 24)
2174 		return RX_DROP_MONITOR;
2175 
2176 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2177 		return RX_DROP_MONITOR;
2178 
2179 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2180 	    ieee80211_is_beacon(mgmt->frame_control) &&
2181 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2182 		int sig = 0;
2183 
2184 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2185 			sig = status->signal;
2186 
2187 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2188 					    rx->skb->data, rx->skb->len,
2189 					    status->freq, sig, GFP_ATOMIC);
2190 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2191 	}
2192 
2193 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2194 		return RX_DROP_MONITOR;
2195 
2196 	if (ieee80211_drop_unencrypted_mgmt(rx))
2197 		return RX_DROP_UNUSABLE;
2198 
2199 	return RX_CONTINUE;
2200 }
2201 
2202 static ieee80211_rx_result debug_noinline
2203 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2204 {
2205 	struct ieee80211_local *local = rx->local;
2206 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2207 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2208 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2209 	int len = rx->skb->len;
2210 
2211 	if (!ieee80211_is_action(mgmt->frame_control))
2212 		return RX_CONTINUE;
2213 
2214 	/* drop too small frames */
2215 	if (len < IEEE80211_MIN_ACTION_SIZE)
2216 		return RX_DROP_UNUSABLE;
2217 
2218 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2219 		return RX_DROP_UNUSABLE;
2220 
2221 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2222 		return RX_DROP_UNUSABLE;
2223 
2224 	switch (mgmt->u.action.category) {
2225 	case WLAN_CATEGORY_HT:
2226 		/* reject HT action frames from stations not supporting HT */
2227 		if (!rx->sta->sta.ht_cap.ht_supported)
2228 			goto invalid;
2229 
2230 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2231 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2232 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2233 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2234 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2235 			break;
2236 
2237 		/* verify action & smps_control are present */
2238 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2239 			goto invalid;
2240 
2241 		switch (mgmt->u.action.u.ht_smps.action) {
2242 		case WLAN_HT_ACTION_SMPS: {
2243 			struct ieee80211_supported_band *sband;
2244 			u8 smps;
2245 
2246 			/* convert to HT capability */
2247 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2248 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2249 				smps = WLAN_HT_CAP_SM_PS_DISABLED;
2250 				break;
2251 			case WLAN_HT_SMPS_CONTROL_STATIC:
2252 				smps = WLAN_HT_CAP_SM_PS_STATIC;
2253 				break;
2254 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2255 				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2256 				break;
2257 			default:
2258 				goto invalid;
2259 			}
2260 			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2261 
2262 			/* if no change do nothing */
2263 			if ((rx->sta->sta.ht_cap.cap &
2264 					IEEE80211_HT_CAP_SM_PS) == smps)
2265 				goto handled;
2266 
2267 			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2268 			rx->sta->sta.ht_cap.cap |= smps;
2269 
2270 			sband = rx->local->hw.wiphy->bands[status->band];
2271 
2272 			rate_control_rate_update(local, sband, rx->sta,
2273 						 IEEE80211_RC_SMPS_CHANGED);
2274 			goto handled;
2275 		}
2276 		default:
2277 			goto invalid;
2278 		}
2279 
2280 		break;
2281 	case WLAN_CATEGORY_BACK:
2282 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2283 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2284 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2285 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2286 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2287 			break;
2288 
2289 		/* verify action_code is present */
2290 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2291 			break;
2292 
2293 		switch (mgmt->u.action.u.addba_req.action_code) {
2294 		case WLAN_ACTION_ADDBA_REQ:
2295 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2296 				   sizeof(mgmt->u.action.u.addba_req)))
2297 				goto invalid;
2298 			break;
2299 		case WLAN_ACTION_ADDBA_RESP:
2300 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2301 				   sizeof(mgmt->u.action.u.addba_resp)))
2302 				goto invalid;
2303 			break;
2304 		case WLAN_ACTION_DELBA:
2305 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2306 				   sizeof(mgmt->u.action.u.delba)))
2307 				goto invalid;
2308 			break;
2309 		default:
2310 			goto invalid;
2311 		}
2312 
2313 		goto queue;
2314 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2315 		if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2316 			break;
2317 
2318 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2319 			break;
2320 
2321 		/* verify action_code is present */
2322 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2323 			break;
2324 
2325 		switch (mgmt->u.action.u.measurement.action_code) {
2326 		case WLAN_ACTION_SPCT_MSR_REQ:
2327 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2328 				   sizeof(mgmt->u.action.u.measurement)))
2329 				break;
2330 			ieee80211_process_measurement_req(sdata, mgmt, len);
2331 			goto handled;
2332 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2333 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2334 				   sizeof(mgmt->u.action.u.chan_switch)))
2335 				break;
2336 
2337 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2338 				break;
2339 
2340 			if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2341 				break;
2342 
2343 			goto queue;
2344 		}
2345 		break;
2346 	case WLAN_CATEGORY_SA_QUERY:
2347 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2348 			   sizeof(mgmt->u.action.u.sa_query)))
2349 			break;
2350 
2351 		switch (mgmt->u.action.u.sa_query.action) {
2352 		case WLAN_ACTION_SA_QUERY_REQUEST:
2353 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2354 				break;
2355 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2356 			goto handled;
2357 		}
2358 		break;
2359 	case WLAN_CATEGORY_SELF_PROTECTED:
2360 		switch (mgmt->u.action.u.self_prot.action_code) {
2361 		case WLAN_SP_MESH_PEERING_OPEN:
2362 		case WLAN_SP_MESH_PEERING_CLOSE:
2363 		case WLAN_SP_MESH_PEERING_CONFIRM:
2364 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2365 				goto invalid;
2366 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2367 				/* userspace handles this frame */
2368 				break;
2369 			goto queue;
2370 		case WLAN_SP_MGK_INFORM:
2371 		case WLAN_SP_MGK_ACK:
2372 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2373 				goto invalid;
2374 			break;
2375 		}
2376 		break;
2377 	case WLAN_CATEGORY_MESH_ACTION:
2378 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2379 			break;
2380 		if (mesh_action_is_path_sel(mgmt) &&
2381 		  (!mesh_path_sel_is_hwmp(sdata)))
2382 			break;
2383 		goto queue;
2384 	}
2385 
2386 	return RX_CONTINUE;
2387 
2388  invalid:
2389 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2390 	/* will return in the next handlers */
2391 	return RX_CONTINUE;
2392 
2393  handled:
2394 	if (rx->sta)
2395 		rx->sta->rx_packets++;
2396 	dev_kfree_skb(rx->skb);
2397 	return RX_QUEUED;
2398 
2399  queue:
2400 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2401 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2402 	ieee80211_queue_work(&local->hw, &sdata->work);
2403 	if (rx->sta)
2404 		rx->sta->rx_packets++;
2405 	return RX_QUEUED;
2406 }
2407 
2408 static ieee80211_rx_result debug_noinline
2409 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2410 {
2411 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2412 	int sig = 0;
2413 
2414 	/* skip known-bad action frames and return them in the next handler */
2415 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2416 		return RX_CONTINUE;
2417 
2418 	/*
2419 	 * Getting here means the kernel doesn't know how to handle
2420 	 * it, but maybe userspace does ... include returned frames
2421 	 * so userspace can register for those to know whether ones
2422 	 * it transmitted were processed or returned.
2423 	 */
2424 
2425 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2426 		sig = status->signal;
2427 
2428 	if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq, sig,
2429 			     rx->skb->data, rx->skb->len,
2430 			     GFP_ATOMIC)) {
2431 		if (rx->sta)
2432 			rx->sta->rx_packets++;
2433 		dev_kfree_skb(rx->skb);
2434 		return RX_QUEUED;
2435 	}
2436 
2437 
2438 	return RX_CONTINUE;
2439 }
2440 
2441 static ieee80211_rx_result debug_noinline
2442 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2443 {
2444 	struct ieee80211_local *local = rx->local;
2445 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2446 	struct sk_buff *nskb;
2447 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2448 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2449 
2450 	if (!ieee80211_is_action(mgmt->frame_control))
2451 		return RX_CONTINUE;
2452 
2453 	/*
2454 	 * For AP mode, hostapd is responsible for handling any action
2455 	 * frames that we didn't handle, including returning unknown
2456 	 * ones. For all other modes we will return them to the sender,
2457 	 * setting the 0x80 bit in the action category, as required by
2458 	 * 802.11-2012 9.24.4.
2459 	 * Newer versions of hostapd shall also use the management frame
2460 	 * registration mechanisms, but older ones still use cooked
2461 	 * monitor interfaces so push all frames there.
2462 	 */
2463 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2464 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2465 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2466 		return RX_DROP_MONITOR;
2467 
2468 	if (is_multicast_ether_addr(mgmt->da))
2469 		return RX_DROP_MONITOR;
2470 
2471 	/* do not return rejected action frames */
2472 	if (mgmt->u.action.category & 0x80)
2473 		return RX_DROP_UNUSABLE;
2474 
2475 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2476 			       GFP_ATOMIC);
2477 	if (nskb) {
2478 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2479 
2480 		nmgmt->u.action.category |= 0x80;
2481 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2482 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2483 
2484 		memset(nskb->cb, 0, sizeof(nskb->cb));
2485 
2486 		ieee80211_tx_skb(rx->sdata, nskb);
2487 	}
2488 	dev_kfree_skb(rx->skb);
2489 	return RX_QUEUED;
2490 }
2491 
2492 static ieee80211_rx_result debug_noinline
2493 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2494 {
2495 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2496 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2497 	__le16 stype;
2498 
2499 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2500 
2501 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2502 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2503 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2504 		return RX_DROP_MONITOR;
2505 
2506 	switch (stype) {
2507 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2508 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2509 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2510 		/* process for all: mesh, mlme, ibss */
2511 		break;
2512 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2513 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2514 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2515 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2516 		if (is_multicast_ether_addr(mgmt->da) &&
2517 		    !is_broadcast_ether_addr(mgmt->da))
2518 			return RX_DROP_MONITOR;
2519 
2520 		/* process only for station */
2521 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2522 			return RX_DROP_MONITOR;
2523 		break;
2524 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2525 		/* process only for ibss */
2526 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2527 			return RX_DROP_MONITOR;
2528 		break;
2529 	default:
2530 		return RX_DROP_MONITOR;
2531 	}
2532 
2533 	/* queue up frame and kick off work to process it */
2534 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2535 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2536 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2537 	if (rx->sta)
2538 		rx->sta->rx_packets++;
2539 
2540 	return RX_QUEUED;
2541 }
2542 
2543 /* TODO: use IEEE80211_RX_FRAGMENTED */
2544 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2545 					struct ieee80211_rate *rate)
2546 {
2547 	struct ieee80211_sub_if_data *sdata;
2548 	struct ieee80211_local *local = rx->local;
2549 	struct sk_buff *skb = rx->skb, *skb2;
2550 	struct net_device *prev_dev = NULL;
2551 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2552 	int needed_headroom;
2553 
2554 	/*
2555 	 * If cooked monitor has been processed already, then
2556 	 * don't do it again. If not, set the flag.
2557 	 */
2558 	if (rx->flags & IEEE80211_RX_CMNTR)
2559 		goto out_free_skb;
2560 	rx->flags |= IEEE80211_RX_CMNTR;
2561 
2562 	/* If there are no cooked monitor interfaces, just free the SKB */
2563 	if (!local->cooked_mntrs)
2564 		goto out_free_skb;
2565 
2566 	/* room for the radiotap header based on driver features */
2567 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
2568 
2569 	if (skb_headroom(skb) < needed_headroom &&
2570 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2571 		goto out_free_skb;
2572 
2573 	/* prepend radiotap information */
2574 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2575 					 false);
2576 
2577 	skb_set_mac_header(skb, 0);
2578 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2579 	skb->pkt_type = PACKET_OTHERHOST;
2580 	skb->protocol = htons(ETH_P_802_2);
2581 
2582 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2583 		if (!ieee80211_sdata_running(sdata))
2584 			continue;
2585 
2586 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2587 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2588 			continue;
2589 
2590 		if (prev_dev) {
2591 			skb2 = skb_clone(skb, GFP_ATOMIC);
2592 			if (skb2) {
2593 				skb2->dev = prev_dev;
2594 				netif_receive_skb(skb2);
2595 			}
2596 		}
2597 
2598 		prev_dev = sdata->dev;
2599 		sdata->dev->stats.rx_packets++;
2600 		sdata->dev->stats.rx_bytes += skb->len;
2601 	}
2602 
2603 	if (prev_dev) {
2604 		skb->dev = prev_dev;
2605 		netif_receive_skb(skb);
2606 		return;
2607 	}
2608 
2609  out_free_skb:
2610 	dev_kfree_skb(skb);
2611 }
2612 
2613 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2614 					 ieee80211_rx_result res)
2615 {
2616 	switch (res) {
2617 	case RX_DROP_MONITOR:
2618 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2619 		if (rx->sta)
2620 			rx->sta->rx_dropped++;
2621 		/* fall through */
2622 	case RX_CONTINUE: {
2623 		struct ieee80211_rate *rate = NULL;
2624 		struct ieee80211_supported_band *sband;
2625 		struct ieee80211_rx_status *status;
2626 
2627 		status = IEEE80211_SKB_RXCB((rx->skb));
2628 
2629 		sband = rx->local->hw.wiphy->bands[status->band];
2630 		if (!(status->flag & RX_FLAG_HT))
2631 			rate = &sband->bitrates[status->rate_idx];
2632 
2633 		ieee80211_rx_cooked_monitor(rx, rate);
2634 		break;
2635 		}
2636 	case RX_DROP_UNUSABLE:
2637 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2638 		if (rx->sta)
2639 			rx->sta->rx_dropped++;
2640 		dev_kfree_skb(rx->skb);
2641 		break;
2642 	case RX_QUEUED:
2643 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2644 		break;
2645 	}
2646 }
2647 
2648 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2649 {
2650 	ieee80211_rx_result res = RX_DROP_MONITOR;
2651 	struct sk_buff *skb;
2652 
2653 #define CALL_RXH(rxh)			\
2654 	do {				\
2655 		res = rxh(rx);		\
2656 		if (res != RX_CONTINUE)	\
2657 			goto rxh_next;  \
2658 	} while (0);
2659 
2660 	spin_lock(&rx->local->rx_skb_queue.lock);
2661 	if (rx->local->running_rx_handler)
2662 		goto unlock;
2663 
2664 	rx->local->running_rx_handler = true;
2665 
2666 	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2667 		spin_unlock(&rx->local->rx_skb_queue.lock);
2668 
2669 		/*
2670 		 * all the other fields are valid across frames
2671 		 * that belong to an aMPDU since they are on the
2672 		 * same TID from the same station
2673 		 */
2674 		rx->skb = skb;
2675 
2676 		CALL_RXH(ieee80211_rx_h_decrypt)
2677 		CALL_RXH(ieee80211_rx_h_check_more_data)
2678 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2679 		CALL_RXH(ieee80211_rx_h_sta_process)
2680 		CALL_RXH(ieee80211_rx_h_defragment)
2681 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2682 		/* must be after MMIC verify so header is counted in MPDU mic */
2683 #ifdef CONFIG_MAC80211_MESH
2684 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2685 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2686 #endif
2687 		CALL_RXH(ieee80211_rx_h_amsdu)
2688 		CALL_RXH(ieee80211_rx_h_data)
2689 		CALL_RXH(ieee80211_rx_h_ctrl);
2690 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2691 		CALL_RXH(ieee80211_rx_h_action)
2692 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2693 		CALL_RXH(ieee80211_rx_h_action_return)
2694 		CALL_RXH(ieee80211_rx_h_mgmt)
2695 
2696  rxh_next:
2697 		ieee80211_rx_handlers_result(rx, res);
2698 		spin_lock(&rx->local->rx_skb_queue.lock);
2699 #undef CALL_RXH
2700 	}
2701 
2702 	rx->local->running_rx_handler = false;
2703 
2704  unlock:
2705 	spin_unlock(&rx->local->rx_skb_queue.lock);
2706 }
2707 
2708 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2709 {
2710 	ieee80211_rx_result res = RX_DROP_MONITOR;
2711 
2712 #define CALL_RXH(rxh)			\
2713 	do {				\
2714 		res = rxh(rx);		\
2715 		if (res != RX_CONTINUE)	\
2716 			goto rxh_next;  \
2717 	} while (0);
2718 
2719 	CALL_RXH(ieee80211_rx_h_passive_scan)
2720 	CALL_RXH(ieee80211_rx_h_check)
2721 
2722 	ieee80211_rx_reorder_ampdu(rx);
2723 
2724 	ieee80211_rx_handlers(rx);
2725 	return;
2726 
2727  rxh_next:
2728 	ieee80211_rx_handlers_result(rx, res);
2729 
2730 #undef CALL_RXH
2731 }
2732 
2733 /*
2734  * This function makes calls into the RX path, therefore
2735  * it has to be invoked under RCU read lock.
2736  */
2737 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2738 {
2739 	struct ieee80211_rx_data rx = {
2740 		.sta = sta,
2741 		.sdata = sta->sdata,
2742 		.local = sta->local,
2743 		/* This is OK -- must be QoS data frame */
2744 		.security_idx = tid,
2745 		.seqno_idx = tid,
2746 		.flags = 0,
2747 	};
2748 	struct tid_ampdu_rx *tid_agg_rx;
2749 
2750 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2751 	if (!tid_agg_rx)
2752 		return;
2753 
2754 	spin_lock(&tid_agg_rx->reorder_lock);
2755 	ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
2756 	spin_unlock(&tid_agg_rx->reorder_lock);
2757 
2758 	ieee80211_rx_handlers(&rx);
2759 }
2760 
2761 /* main receive path */
2762 
2763 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2764 				struct ieee80211_hdr *hdr)
2765 {
2766 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2767 	struct sk_buff *skb = rx->skb;
2768 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2769 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2770 	int multicast = is_multicast_ether_addr(hdr->addr1);
2771 
2772 	switch (sdata->vif.type) {
2773 	case NL80211_IFTYPE_STATION:
2774 		if (!bssid && !sdata->u.mgd.use_4addr)
2775 			return 0;
2776 		if (!multicast &&
2777 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2778 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2779 			    sdata->u.mgd.use_4addr)
2780 				return 0;
2781 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2782 		}
2783 		break;
2784 	case NL80211_IFTYPE_ADHOC:
2785 		if (!bssid)
2786 			return 0;
2787 		if (ieee80211_is_beacon(hdr->frame_control)) {
2788 			return 1;
2789 		}
2790 		else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2791 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2792 				return 0;
2793 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2794 		} else if (!multicast &&
2795 			   !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2796 			if (!(sdata->dev->flags & IFF_PROMISC))
2797 				return 0;
2798 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2799 		} else if (!rx->sta) {
2800 			int rate_idx;
2801 			if (status->flag & RX_FLAG_HT)
2802 				rate_idx = 0; /* TODO: HT rates */
2803 			else
2804 				rate_idx = status->rate_idx;
2805 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2806 						 BIT(rate_idx));
2807 		}
2808 		break;
2809 	case NL80211_IFTYPE_MESH_POINT:
2810 		if (!multicast &&
2811 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2812 			if (!(sdata->dev->flags & IFF_PROMISC))
2813 				return 0;
2814 
2815 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2816 		}
2817 		break;
2818 	case NL80211_IFTYPE_AP_VLAN:
2819 	case NL80211_IFTYPE_AP:
2820 		if (!bssid) {
2821 			if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2822 				return 0;
2823 		} else if (!ieee80211_bssid_match(bssid,
2824 					sdata->vif.addr)) {
2825 			/*
2826 			 * Accept public action frames even when the
2827 			 * BSSID doesn't match, this is used for P2P
2828 			 * and location updates. Note that mac80211
2829 			 * itself never looks at these frames.
2830 			 */
2831 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2832 			    ieee80211_is_public_action(hdr, skb->len))
2833 				return 1;
2834 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2835 			    !ieee80211_is_beacon(hdr->frame_control))
2836 				return 0;
2837 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2838 		}
2839 		break;
2840 	case NL80211_IFTYPE_WDS:
2841 		if (bssid || !ieee80211_is_data(hdr->frame_control))
2842 			return 0;
2843 		if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
2844 			return 0;
2845 		break;
2846 	default:
2847 		/* should never get here */
2848 		WARN_ON(1);
2849 		break;
2850 	}
2851 
2852 	return 1;
2853 }
2854 
2855 /*
2856  * This function returns whether or not the SKB
2857  * was destined for RX processing or not, which,
2858  * if consume is true, is equivalent to whether
2859  * or not the skb was consumed.
2860  */
2861 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2862 					    struct sk_buff *skb, bool consume)
2863 {
2864 	struct ieee80211_local *local = rx->local;
2865 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2866 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2867 	struct ieee80211_hdr *hdr = (void *)skb->data;
2868 	int prepares;
2869 
2870 	rx->skb = skb;
2871 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
2872 	prepares = prepare_for_handlers(rx, hdr);
2873 
2874 	if (!prepares)
2875 		return false;
2876 
2877 	if (!consume) {
2878 		skb = skb_copy(skb, GFP_ATOMIC);
2879 		if (!skb) {
2880 			if (net_ratelimit())
2881 				wiphy_debug(local->hw.wiphy,
2882 					"failed to copy skb for %s\n",
2883 					sdata->name);
2884 			return true;
2885 		}
2886 
2887 		rx->skb = skb;
2888 	}
2889 
2890 	ieee80211_invoke_rx_handlers(rx);
2891 	return true;
2892 }
2893 
2894 /*
2895  * This is the actual Rx frames handler. as it blongs to Rx path it must
2896  * be called with rcu_read_lock protection.
2897  */
2898 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2899 					 struct sk_buff *skb)
2900 {
2901 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2902 	struct ieee80211_local *local = hw_to_local(hw);
2903 	struct ieee80211_sub_if_data *sdata;
2904 	struct ieee80211_hdr *hdr;
2905 	__le16 fc;
2906 	struct ieee80211_rx_data rx;
2907 	struct ieee80211_sub_if_data *prev;
2908 	struct sta_info *sta, *tmp, *prev_sta;
2909 	int err = 0;
2910 
2911 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2912 	memset(&rx, 0, sizeof(rx));
2913 	rx.skb = skb;
2914 	rx.local = local;
2915 
2916 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2917 		local->dot11ReceivedFragmentCount++;
2918 
2919 	if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2920 		     test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning) ||
2921 		     test_bit(SCAN_SW_SCANNING, &local->scanning)))
2922 		status->rx_flags |= IEEE80211_RX_IN_SCAN;
2923 
2924 	if (ieee80211_is_mgmt(fc))
2925 		err = skb_linearize(skb);
2926 	else
2927 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2928 
2929 	if (err) {
2930 		dev_kfree_skb(skb);
2931 		return;
2932 	}
2933 
2934 	hdr = (struct ieee80211_hdr *)skb->data;
2935 	ieee80211_parse_qos(&rx);
2936 	ieee80211_verify_alignment(&rx);
2937 
2938 	if (ieee80211_is_data(fc)) {
2939 		prev_sta = NULL;
2940 
2941 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
2942 			if (!prev_sta) {
2943 				prev_sta = sta;
2944 				continue;
2945 			}
2946 
2947 			rx.sta = prev_sta;
2948 			rx.sdata = prev_sta->sdata;
2949 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
2950 
2951 			prev_sta = sta;
2952 		}
2953 
2954 		if (prev_sta) {
2955 			rx.sta = prev_sta;
2956 			rx.sdata = prev_sta->sdata;
2957 
2958 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2959 				return;
2960 			goto out;
2961 		}
2962 	}
2963 
2964 	prev = NULL;
2965 
2966 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2967 		if (!ieee80211_sdata_running(sdata))
2968 			continue;
2969 
2970 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2971 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2972 			continue;
2973 
2974 		/*
2975 		 * frame is destined for this interface, but if it's
2976 		 * not also for the previous one we handle that after
2977 		 * the loop to avoid copying the SKB once too much
2978 		 */
2979 
2980 		if (!prev) {
2981 			prev = sdata;
2982 			continue;
2983 		}
2984 
2985 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2986 		rx.sdata = prev;
2987 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
2988 
2989 		prev = sdata;
2990 	}
2991 
2992 	if (prev) {
2993 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2994 		rx.sdata = prev;
2995 
2996 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2997 			return;
2998 	}
2999 
3000  out:
3001 	dev_kfree_skb(skb);
3002 }
3003 
3004 /*
3005  * This is the receive path handler. It is called by a low level driver when an
3006  * 802.11 MPDU is received from the hardware.
3007  */
3008 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3009 {
3010 	struct ieee80211_local *local = hw_to_local(hw);
3011 	struct ieee80211_rate *rate = NULL;
3012 	struct ieee80211_supported_band *sband;
3013 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3014 
3015 	WARN_ON_ONCE(softirq_count() == 0);
3016 
3017 	if (WARN_ON(status->band < 0 ||
3018 		    status->band >= IEEE80211_NUM_BANDS))
3019 		goto drop;
3020 
3021 	sband = local->hw.wiphy->bands[status->band];
3022 	if (WARN_ON(!sband))
3023 		goto drop;
3024 
3025 	/*
3026 	 * If we're suspending, it is possible although not too likely
3027 	 * that we'd be receiving frames after having already partially
3028 	 * quiesced the stack. We can't process such frames then since
3029 	 * that might, for example, cause stations to be added or other
3030 	 * driver callbacks be invoked.
3031 	 */
3032 	if (unlikely(local->quiescing || local->suspended))
3033 		goto drop;
3034 
3035 	/*
3036 	 * The same happens when we're not even started,
3037 	 * but that's worth a warning.
3038 	 */
3039 	if (WARN_ON(!local->started))
3040 		goto drop;
3041 
3042 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3043 		/*
3044 		 * Validate the rate, unless a PLCP error means that
3045 		 * we probably can't have a valid rate here anyway.
3046 		 */
3047 
3048 		if (status->flag & RX_FLAG_HT) {
3049 			/*
3050 			 * rate_idx is MCS index, which can be [0-76]
3051 			 * as documented on:
3052 			 *
3053 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3054 			 *
3055 			 * Anything else would be some sort of driver or
3056 			 * hardware error. The driver should catch hardware
3057 			 * errors.
3058 			 */
3059 			if (WARN((status->rate_idx < 0 ||
3060 				 status->rate_idx > 76),
3061 				 "Rate marked as an HT rate but passed "
3062 				 "status->rate_idx is not "
3063 				 "an MCS index [0-76]: %d (0x%02x)\n",
3064 				 status->rate_idx,
3065 				 status->rate_idx))
3066 				goto drop;
3067 		} else {
3068 			if (WARN_ON(status->rate_idx < 0 ||
3069 				    status->rate_idx >= sband->n_bitrates))
3070 				goto drop;
3071 			rate = &sband->bitrates[status->rate_idx];
3072 		}
3073 	}
3074 
3075 	status->rx_flags = 0;
3076 
3077 	/*
3078 	 * key references and virtual interfaces are protected using RCU
3079 	 * and this requires that we are in a read-side RCU section during
3080 	 * receive processing
3081 	 */
3082 	rcu_read_lock();
3083 
3084 	/*
3085 	 * Frames with failed FCS/PLCP checksum are not returned,
3086 	 * all other frames are returned without radiotap header
3087 	 * if it was previously present.
3088 	 * Also, frames with less than 16 bytes are dropped.
3089 	 */
3090 	skb = ieee80211_rx_monitor(local, skb, rate);
3091 	if (!skb) {
3092 		rcu_read_unlock();
3093 		return;
3094 	}
3095 
3096 	ieee80211_tpt_led_trig_rx(local,
3097 			((struct ieee80211_hdr *)skb->data)->frame_control,
3098 			skb->len);
3099 	__ieee80211_rx_handle_packet(hw, skb);
3100 
3101 	rcu_read_unlock();
3102 
3103 	return;
3104  drop:
3105 	kfree_skb(skb);
3106 }
3107 EXPORT_SYMBOL(ieee80211_rx);
3108 
3109 /* This is a version of the rx handler that can be called from hard irq
3110  * context. Post the skb on the queue and schedule the tasklet */
3111 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3112 {
3113 	struct ieee80211_local *local = hw_to_local(hw);
3114 
3115 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3116 
3117 	skb->pkt_type = IEEE80211_RX_MSG;
3118 	skb_queue_tail(&local->skb_queue, skb);
3119 	tasklet_schedule(&local->tasklet);
3120 }
3121 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3122