xref: /openbmc/linux/net/mac80211/rx.c (revision 9d749629)
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 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
44 
45 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
46 		if (likely(skb->len > FCS_LEN))
47 			__pskb_trim(skb, skb->len - FCS_LEN);
48 		else {
49 			/* driver bug */
50 			WARN_ON(1);
51 			dev_kfree_skb(skb);
52 			return NULL;
53 		}
54 	}
55 
56 	if (status->vendor_radiotap_len)
57 		__pskb_pull(skb, status->vendor_radiotap_len);
58 
59 	return skb;
60 }
61 
62 static inline int should_drop_frame(struct sk_buff *skb, int present_fcs_len)
63 {
64 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
65 	struct ieee80211_hdr *hdr;
66 
67 	hdr = (void *)(skb->data + status->vendor_radiotap_len);
68 
69 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
70 			    RX_FLAG_FAILED_PLCP_CRC |
71 			    RX_FLAG_AMPDU_IS_ZEROLEN))
72 		return 1;
73 	if (unlikely(skb->len < 16 + present_fcs_len +
74 				status->vendor_radiotap_len))
75 		return 1;
76 	if (ieee80211_is_ctl(hdr->frame_control) &&
77 	    !ieee80211_is_pspoll(hdr->frame_control) &&
78 	    !ieee80211_is_back_req(hdr->frame_control))
79 		return 1;
80 	return 0;
81 }
82 
83 static int
84 ieee80211_rx_radiotap_space(struct ieee80211_local *local,
85 			    struct ieee80211_rx_status *status)
86 {
87 	int len;
88 
89 	/* always present fields */
90 	len = sizeof(struct ieee80211_radiotap_header) + 9;
91 
92 	/* allocate extra bitmap */
93 	if (status->vendor_radiotap_len)
94 		len += 4;
95 
96 	if (ieee80211_have_rx_timestamp(status)) {
97 		len = ALIGN(len, 8);
98 		len += 8;
99 	}
100 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
101 		len += 1;
102 
103 	/* padding for RX_FLAGS if necessary */
104 	len = ALIGN(len, 2);
105 
106 	if (status->flag & RX_FLAG_HT) /* HT info */
107 		len += 3;
108 
109 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
110 		len = ALIGN(len, 4);
111 		len += 8;
112 	}
113 
114 	if (status->flag & RX_FLAG_VHT) {
115 		len = ALIGN(len, 2);
116 		len += 12;
117 	}
118 
119 	if (status->vendor_radiotap_len) {
120 		if (WARN_ON_ONCE(status->vendor_radiotap_align == 0))
121 			status->vendor_radiotap_align = 1;
122 		/* align standard part of vendor namespace */
123 		len = ALIGN(len, 2);
124 		/* allocate standard part of vendor namespace */
125 		len += 6;
126 		/* align vendor-defined part */
127 		len = ALIGN(len, status->vendor_radiotap_align);
128 		/* vendor-defined part is already in skb */
129 	}
130 
131 	return len;
132 }
133 
134 /*
135  * ieee80211_add_rx_radiotap_header - add radiotap header
136  *
137  * add a radiotap header containing all the fields which the hardware provided.
138  */
139 static void
140 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
141 				 struct sk_buff *skb,
142 				 struct ieee80211_rate *rate,
143 				 int rtap_len, bool has_fcs)
144 {
145 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
146 	struct ieee80211_radiotap_header *rthdr;
147 	unsigned char *pos;
148 	u16 rx_flags = 0;
149 	int mpdulen;
150 
151 	mpdulen = skb->len;
152 	if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)))
153 		mpdulen += FCS_LEN;
154 
155 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
156 	memset(rthdr, 0, rtap_len);
157 
158 	/* radiotap header, set always present flags */
159 	rthdr->it_present =
160 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
161 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
162 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
163 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
164 	rthdr->it_len = cpu_to_le16(rtap_len + status->vendor_radiotap_len);
165 
166 	pos = (unsigned char *)(rthdr + 1);
167 
168 	if (status->vendor_radiotap_len) {
169 		rthdr->it_present |=
170 			cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) |
171 			cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT));
172 		put_unaligned_le32(status->vendor_radiotap_bitmap, pos);
173 		pos += 4;
174 	}
175 
176 	/* the order of the following fields is important */
177 
178 	/* IEEE80211_RADIOTAP_TSFT */
179 	if (ieee80211_have_rx_timestamp(status)) {
180 		/* padding */
181 		while ((pos - (u8 *)rthdr) & 7)
182 			*pos++ = 0;
183 		put_unaligned_le64(
184 			ieee80211_calculate_rx_timestamp(local, status,
185 							 mpdulen, 0),
186 			pos);
187 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
188 		pos += 8;
189 	}
190 
191 	/* IEEE80211_RADIOTAP_FLAGS */
192 	if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
193 		*pos |= IEEE80211_RADIOTAP_F_FCS;
194 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
195 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
196 	if (status->flag & RX_FLAG_SHORTPRE)
197 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
198 	pos++;
199 
200 	/* IEEE80211_RADIOTAP_RATE */
201 	if (!rate || status->flag & (RX_FLAG_HT | RX_FLAG_VHT)) {
202 		/*
203 		 * Without rate information don't add it. If we have,
204 		 * MCS information is a separate field in radiotap,
205 		 * added below. The byte here is needed as padding
206 		 * for the channel though, so initialise it to 0.
207 		 */
208 		*pos = 0;
209 	} else {
210 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
211 		*pos = rate->bitrate / 5;
212 	}
213 	pos++;
214 
215 	/* IEEE80211_RADIOTAP_CHANNEL */
216 	put_unaligned_le16(status->freq, pos);
217 	pos += 2;
218 	if (status->band == IEEE80211_BAND_5GHZ)
219 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
220 				   pos);
221 	else if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
222 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
223 				   pos);
224 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
225 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
226 				   pos);
227 	else if (rate)
228 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
229 				   pos);
230 	else
231 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
232 	pos += 2;
233 
234 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
235 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
236 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
237 		*pos = status->signal;
238 		rthdr->it_present |=
239 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
240 		pos++;
241 	}
242 
243 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
244 
245 	/* IEEE80211_RADIOTAP_ANTENNA */
246 	*pos = status->antenna;
247 	pos++;
248 
249 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
250 
251 	/* IEEE80211_RADIOTAP_RX_FLAGS */
252 	/* ensure 2 byte alignment for the 2 byte field as required */
253 	if ((pos - (u8 *)rthdr) & 1)
254 		*pos++ = 0;
255 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
256 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
257 	put_unaligned_le16(rx_flags, pos);
258 	pos += 2;
259 
260 	if (status->flag & RX_FLAG_HT) {
261 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
262 		*pos++ = local->hw.radiotap_mcs_details;
263 		*pos = 0;
264 		if (status->flag & RX_FLAG_SHORT_GI)
265 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
266 		if (status->flag & RX_FLAG_40MHZ)
267 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
268 		if (status->flag & RX_FLAG_HT_GF)
269 			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
270 		pos++;
271 		*pos++ = status->rate_idx;
272 	}
273 
274 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
275 		u16 flags = 0;
276 
277 		/* ensure 4 byte alignment */
278 		while ((pos - (u8 *)rthdr) & 3)
279 			pos++;
280 		rthdr->it_present |=
281 			cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
282 		put_unaligned_le32(status->ampdu_reference, pos);
283 		pos += 4;
284 		if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
285 			flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
286 		if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
287 			flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
288 		if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
289 			flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
290 		if (status->flag & RX_FLAG_AMPDU_IS_LAST)
291 			flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
292 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
293 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
294 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
295 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
296 		put_unaligned_le16(flags, pos);
297 		pos += 2;
298 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
299 			*pos++ = status->ampdu_delimiter_crc;
300 		else
301 			*pos++ = 0;
302 		*pos++ = 0;
303 	}
304 
305 	if (status->flag & RX_FLAG_VHT) {
306 		u16 known = local->hw.radiotap_vht_details;
307 
308 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
309 		/* known field - how to handle 80+80? */
310 		if (status->flag & RX_FLAG_80P80MHZ)
311 			known &= ~IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
312 		put_unaligned_le16(known, pos);
313 		pos += 2;
314 		/* flags */
315 		if (status->flag & RX_FLAG_SHORT_GI)
316 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
317 		pos++;
318 		/* bandwidth */
319 		if (status->flag & RX_FLAG_80MHZ)
320 			*pos++ = 4;
321 		else if (status->flag & RX_FLAG_80P80MHZ)
322 			*pos++ = 0; /* marked not known above */
323 		else if (status->flag & RX_FLAG_160MHZ)
324 			*pos++ = 11;
325 		else if (status->flag & RX_FLAG_40MHZ)
326 			*pos++ = 1;
327 		else /* 20 MHz */
328 			*pos++ = 0;
329 		/* MCS/NSS */
330 		*pos = (status->rate_idx << 4) | status->vht_nss;
331 		pos += 4;
332 		/* coding field */
333 		pos++;
334 		/* group ID */
335 		pos++;
336 		/* partial_aid */
337 		pos += 2;
338 	}
339 
340 	if (status->vendor_radiotap_len) {
341 		/* ensure 2 byte alignment for the vendor field as required */
342 		if ((pos - (u8 *)rthdr) & 1)
343 			*pos++ = 0;
344 		*pos++ = status->vendor_radiotap_oui[0];
345 		*pos++ = status->vendor_radiotap_oui[1];
346 		*pos++ = status->vendor_radiotap_oui[2];
347 		*pos++ = status->vendor_radiotap_subns;
348 		put_unaligned_le16(status->vendor_radiotap_len, pos);
349 		pos += 2;
350 		/* align the actual payload as requested */
351 		while ((pos - (u8 *)rthdr) & (status->vendor_radiotap_align - 1))
352 			*pos++ = 0;
353 	}
354 }
355 
356 /*
357  * This function copies a received frame to all monitor interfaces and
358  * returns a cleaned-up SKB that no longer includes the FCS nor the
359  * radiotap header the driver might have added.
360  */
361 static struct sk_buff *
362 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
363 		     struct ieee80211_rate *rate)
364 {
365 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
366 	struct ieee80211_sub_if_data *sdata;
367 	int needed_headroom;
368 	struct sk_buff *skb, *skb2;
369 	struct net_device *prev_dev = NULL;
370 	int present_fcs_len = 0;
371 
372 	/*
373 	 * First, we may need to make a copy of the skb because
374 	 *  (1) we need to modify it for radiotap (if not present), and
375 	 *  (2) the other RX handlers will modify the skb we got.
376 	 *
377 	 * We don't need to, of course, if we aren't going to return
378 	 * the SKB because it has a bad FCS/PLCP checksum.
379 	 */
380 
381 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
382 		present_fcs_len = FCS_LEN;
383 
384 	/* ensure hdr->frame_control and vendor radiotap data are in skb head */
385 	if (!pskb_may_pull(origskb, 2 + status->vendor_radiotap_len)) {
386 		dev_kfree_skb(origskb);
387 		return NULL;
388 	}
389 
390 	if (!local->monitors) {
391 		if (should_drop_frame(origskb, present_fcs_len)) {
392 			dev_kfree_skb(origskb);
393 			return NULL;
394 		}
395 
396 		return remove_monitor_info(local, origskb);
397 	}
398 
399 	/* room for the radiotap header based on driver features */
400 	needed_headroom = ieee80211_rx_radiotap_space(local, status);
401 
402 	if (should_drop_frame(origskb, present_fcs_len)) {
403 		/* only need to expand headroom if necessary */
404 		skb = origskb;
405 		origskb = NULL;
406 
407 		/*
408 		 * This shouldn't trigger often because most devices have an
409 		 * RX header they pull before we get here, and that should
410 		 * be big enough for our radiotap information. We should
411 		 * probably export the length to drivers so that we can have
412 		 * them allocate enough headroom to start with.
413 		 */
414 		if (skb_headroom(skb) < needed_headroom &&
415 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
416 			dev_kfree_skb(skb);
417 			return NULL;
418 		}
419 	} else {
420 		/*
421 		 * Need to make a copy and possibly remove radiotap header
422 		 * and FCS from the original.
423 		 */
424 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
425 
426 		origskb = remove_monitor_info(local, origskb);
427 
428 		if (!skb)
429 			return origskb;
430 	}
431 
432 	/* prepend radiotap information */
433 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
434 					 true);
435 
436 	skb_reset_mac_header(skb);
437 	skb->ip_summed = CHECKSUM_UNNECESSARY;
438 	skb->pkt_type = PACKET_OTHERHOST;
439 	skb->protocol = htons(ETH_P_802_2);
440 
441 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
442 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
443 			continue;
444 
445 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
446 			continue;
447 
448 		if (!ieee80211_sdata_running(sdata))
449 			continue;
450 
451 		if (prev_dev) {
452 			skb2 = skb_clone(skb, GFP_ATOMIC);
453 			if (skb2) {
454 				skb2->dev = prev_dev;
455 				netif_receive_skb(skb2);
456 			}
457 		}
458 
459 		prev_dev = sdata->dev;
460 		sdata->dev->stats.rx_packets++;
461 		sdata->dev->stats.rx_bytes += skb->len;
462 	}
463 
464 	if (prev_dev) {
465 		skb->dev = prev_dev;
466 		netif_receive_skb(skb);
467 	} else
468 		dev_kfree_skb(skb);
469 
470 	return origskb;
471 }
472 
473 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
474 {
475 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
476 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
477 	int tid, seqno_idx, security_idx;
478 
479 	/* does the frame have a qos control field? */
480 	if (ieee80211_is_data_qos(hdr->frame_control)) {
481 		u8 *qc = ieee80211_get_qos_ctl(hdr);
482 		/* frame has qos control */
483 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
484 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
485 			status->rx_flags |= IEEE80211_RX_AMSDU;
486 
487 		seqno_idx = tid;
488 		security_idx = tid;
489 	} else {
490 		/*
491 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
492 		 *
493 		 *	Sequence numbers for management frames, QoS data
494 		 *	frames with a broadcast/multicast address in the
495 		 *	Address 1 field, and all non-QoS data frames sent
496 		 *	by QoS STAs are assigned using an additional single
497 		 *	modulo-4096 counter, [...]
498 		 *
499 		 * We also use that counter for non-QoS STAs.
500 		 */
501 		seqno_idx = IEEE80211_NUM_TIDS;
502 		security_idx = 0;
503 		if (ieee80211_is_mgmt(hdr->frame_control))
504 			security_idx = IEEE80211_NUM_TIDS;
505 		tid = 0;
506 	}
507 
508 	rx->seqno_idx = seqno_idx;
509 	rx->security_idx = security_idx;
510 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
511 	 * For now, set skb->priority to 0 for other cases. */
512 	rx->skb->priority = (tid > 7) ? 0 : tid;
513 }
514 
515 /**
516  * DOC: Packet alignment
517  *
518  * Drivers always need to pass packets that are aligned to two-byte boundaries
519  * to the stack.
520  *
521  * Additionally, should, if possible, align the payload data in a way that
522  * guarantees that the contained IP header is aligned to a four-byte
523  * boundary. In the case of regular frames, this simply means aligning the
524  * payload to a four-byte boundary (because either the IP header is directly
525  * contained, or IV/RFC1042 headers that have a length divisible by four are
526  * in front of it).  If the payload data is not properly aligned and the
527  * architecture doesn't support efficient unaligned operations, mac80211
528  * will align the data.
529  *
530  * With A-MSDU frames, however, the payload data address must yield two modulo
531  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
532  * push the IP header further back to a multiple of four again. Thankfully, the
533  * specs were sane enough this time around to require padding each A-MSDU
534  * subframe to a length that is a multiple of four.
535  *
536  * Padding like Atheros hardware adds which is between the 802.11 header and
537  * the payload is not supported, the driver is required to move the 802.11
538  * header to be directly in front of the payload in that case.
539  */
540 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
541 {
542 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
543 	WARN_ONCE((unsigned long)rx->skb->data & 1,
544 		  "unaligned packet at 0x%p\n", rx->skb->data);
545 #endif
546 }
547 
548 
549 /* rx handlers */
550 
551 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
552 {
553 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
554 
555 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
556 		return 0;
557 
558 	return ieee80211_is_robust_mgmt_frame(hdr);
559 }
560 
561 
562 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
563 {
564 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
565 
566 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
567 		return 0;
568 
569 	return ieee80211_is_robust_mgmt_frame(hdr);
570 }
571 
572 
573 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
574 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
575 {
576 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
577 	struct ieee80211_mmie *mmie;
578 
579 	if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
580 		return -1;
581 
582 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
583 		return -1; /* not a robust management frame */
584 
585 	mmie = (struct ieee80211_mmie *)
586 		(skb->data + skb->len - sizeof(*mmie));
587 	if (mmie->element_id != WLAN_EID_MMIE ||
588 	    mmie->length != sizeof(*mmie) - 2)
589 		return -1;
590 
591 	return le16_to_cpu(mmie->key_id);
592 }
593 
594 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
595 {
596 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
597 	char *dev_addr = rx->sdata->vif.addr;
598 
599 	if (ieee80211_is_data(hdr->frame_control)) {
600 		if (is_multicast_ether_addr(hdr->addr1)) {
601 			if (ieee80211_has_tods(hdr->frame_control) ||
602 			    !ieee80211_has_fromds(hdr->frame_control))
603 				return RX_DROP_MONITOR;
604 			if (ether_addr_equal(hdr->addr3, dev_addr))
605 				return RX_DROP_MONITOR;
606 		} else {
607 			if (!ieee80211_has_a4(hdr->frame_control))
608 				return RX_DROP_MONITOR;
609 			if (ether_addr_equal(hdr->addr4, dev_addr))
610 				return RX_DROP_MONITOR;
611 		}
612 	}
613 
614 	/* If there is not an established peer link and this is not a peer link
615 	 * establisment frame, beacon or probe, drop the frame.
616 	 */
617 
618 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
619 		struct ieee80211_mgmt *mgmt;
620 
621 		if (!ieee80211_is_mgmt(hdr->frame_control))
622 			return RX_DROP_MONITOR;
623 
624 		if (ieee80211_is_action(hdr->frame_control)) {
625 			u8 category;
626 
627 			/* make sure category field is present */
628 			if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
629 				return RX_DROP_MONITOR;
630 
631 			mgmt = (struct ieee80211_mgmt *)hdr;
632 			category = mgmt->u.action.category;
633 			if (category != WLAN_CATEGORY_MESH_ACTION &&
634 			    category != WLAN_CATEGORY_SELF_PROTECTED)
635 				return RX_DROP_MONITOR;
636 			return RX_CONTINUE;
637 		}
638 
639 		if (ieee80211_is_probe_req(hdr->frame_control) ||
640 		    ieee80211_is_probe_resp(hdr->frame_control) ||
641 		    ieee80211_is_beacon(hdr->frame_control) ||
642 		    ieee80211_is_auth(hdr->frame_control))
643 			return RX_CONTINUE;
644 
645 		return RX_DROP_MONITOR;
646 	}
647 
648 	return RX_CONTINUE;
649 }
650 
651 #define SEQ_MODULO 0x1000
652 #define SEQ_MASK   0xfff
653 
654 static inline int seq_less(u16 sq1, u16 sq2)
655 {
656 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
657 }
658 
659 static inline u16 seq_inc(u16 sq)
660 {
661 	return (sq + 1) & SEQ_MASK;
662 }
663 
664 static inline u16 seq_sub(u16 sq1, u16 sq2)
665 {
666 	return (sq1 - sq2) & SEQ_MASK;
667 }
668 
669 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
670 					    struct tid_ampdu_rx *tid_agg_rx,
671 					    int index,
672 					    struct sk_buff_head *frames)
673 {
674 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
675 	struct ieee80211_rx_status *status;
676 
677 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
678 
679 	if (!skb)
680 		goto no_frame;
681 
682 	/* release the frame from the reorder ring buffer */
683 	tid_agg_rx->stored_mpdu_num--;
684 	tid_agg_rx->reorder_buf[index] = NULL;
685 	status = IEEE80211_SKB_RXCB(skb);
686 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
687 	__skb_queue_tail(frames, skb);
688 
689 no_frame:
690 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
691 }
692 
693 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
694 					     struct tid_ampdu_rx *tid_agg_rx,
695 					     u16 head_seq_num,
696 					     struct sk_buff_head *frames)
697 {
698 	int index;
699 
700 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
701 
702 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
703 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
704 							tid_agg_rx->buf_size;
705 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
706 						frames);
707 	}
708 }
709 
710 /*
711  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
712  * the skb was added to the buffer longer than this time ago, the earlier
713  * frames that have not yet been received are assumed to be lost and the skb
714  * can be released for processing. This may also release other skb's from the
715  * reorder buffer if there are no additional gaps between the frames.
716  *
717  * Callers must hold tid_agg_rx->reorder_lock.
718  */
719 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
720 
721 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
722 					  struct tid_ampdu_rx *tid_agg_rx,
723 					  struct sk_buff_head *frames)
724 {
725 	int index, j;
726 
727 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
728 
729 	/* release the buffer until next missing frame */
730 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
731 						tid_agg_rx->buf_size;
732 	if (!tid_agg_rx->reorder_buf[index] &&
733 	    tid_agg_rx->stored_mpdu_num) {
734 		/*
735 		 * No buffers ready to be released, but check whether any
736 		 * frames in the reorder buffer have timed out.
737 		 */
738 		int skipped = 1;
739 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
740 		     j = (j + 1) % tid_agg_rx->buf_size) {
741 			if (!tid_agg_rx->reorder_buf[j]) {
742 				skipped++;
743 				continue;
744 			}
745 			if (skipped &&
746 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
747 					HT_RX_REORDER_BUF_TIMEOUT))
748 				goto set_release_timer;
749 
750 			ht_dbg_ratelimited(sdata,
751 					   "release an RX reorder frame due to timeout on earlier frames\n");
752 			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
753 							frames);
754 
755 			/*
756 			 * Increment the head seq# also for the skipped slots.
757 			 */
758 			tid_agg_rx->head_seq_num =
759 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
760 			skipped = 0;
761 		}
762 	} else while (tid_agg_rx->reorder_buf[index]) {
763 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
764 						frames);
765 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
766 							tid_agg_rx->buf_size;
767 	}
768 
769 	if (tid_agg_rx->stored_mpdu_num) {
770 		j = index = seq_sub(tid_agg_rx->head_seq_num,
771 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
772 
773 		for (; j != (index - 1) % tid_agg_rx->buf_size;
774 		     j = (j + 1) % tid_agg_rx->buf_size) {
775 			if (tid_agg_rx->reorder_buf[j])
776 				break;
777 		}
778 
779  set_release_timer:
780 
781 		mod_timer(&tid_agg_rx->reorder_timer,
782 			  tid_agg_rx->reorder_time[j] + 1 +
783 			  HT_RX_REORDER_BUF_TIMEOUT);
784 	} else {
785 		del_timer(&tid_agg_rx->reorder_timer);
786 	}
787 }
788 
789 /*
790  * As this function belongs to the RX path it must be under
791  * rcu_read_lock protection. It returns false if the frame
792  * can be processed immediately, true if it was consumed.
793  */
794 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
795 					     struct tid_ampdu_rx *tid_agg_rx,
796 					     struct sk_buff *skb,
797 					     struct sk_buff_head *frames)
798 {
799 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
800 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
801 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
802 	u16 head_seq_num, buf_size;
803 	int index;
804 	bool ret = true;
805 
806 	spin_lock(&tid_agg_rx->reorder_lock);
807 
808 	buf_size = tid_agg_rx->buf_size;
809 	head_seq_num = tid_agg_rx->head_seq_num;
810 
811 	/* frame with out of date sequence number */
812 	if (seq_less(mpdu_seq_num, head_seq_num)) {
813 		dev_kfree_skb(skb);
814 		goto out;
815 	}
816 
817 	/*
818 	 * If frame the sequence number exceeds our buffering window
819 	 * size release some previous frames to make room for this one.
820 	 */
821 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
822 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
823 		/* release stored frames up to new head to stack */
824 		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
825 						 head_seq_num, frames);
826 	}
827 
828 	/* Now the new frame is always in the range of the reordering buffer */
829 
830 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
831 
832 	/* check if we already stored this frame */
833 	if (tid_agg_rx->reorder_buf[index]) {
834 		dev_kfree_skb(skb);
835 		goto out;
836 	}
837 
838 	/*
839 	 * If the current MPDU is in the right order and nothing else
840 	 * is stored we can process it directly, no need to buffer it.
841 	 * If it is first but there's something stored, we may be able
842 	 * to release frames after this one.
843 	 */
844 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
845 	    tid_agg_rx->stored_mpdu_num == 0) {
846 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
847 		ret = false;
848 		goto out;
849 	}
850 
851 	/* put the frame in the reordering buffer */
852 	tid_agg_rx->reorder_buf[index] = skb;
853 	tid_agg_rx->reorder_time[index] = jiffies;
854 	tid_agg_rx->stored_mpdu_num++;
855 	ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
856 
857  out:
858 	spin_unlock(&tid_agg_rx->reorder_lock);
859 	return ret;
860 }
861 
862 /*
863  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
864  * true if the MPDU was buffered, false if it should be processed.
865  */
866 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
867 				       struct sk_buff_head *frames)
868 {
869 	struct sk_buff *skb = rx->skb;
870 	struct ieee80211_local *local = rx->local;
871 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
872 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
873 	struct sta_info *sta = rx->sta;
874 	struct tid_ampdu_rx *tid_agg_rx;
875 	u16 sc;
876 	u8 tid, ack_policy;
877 
878 	if (!ieee80211_is_data_qos(hdr->frame_control))
879 		goto dont_reorder;
880 
881 	/*
882 	 * filter the QoS data rx stream according to
883 	 * STA/TID and check if this STA/TID is on aggregation
884 	 */
885 
886 	if (!sta)
887 		goto dont_reorder;
888 
889 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
890 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
891 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
892 
893 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
894 	if (!tid_agg_rx)
895 		goto dont_reorder;
896 
897 	/* qos null data frames are excluded */
898 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
899 		goto dont_reorder;
900 
901 	/* not part of a BA session */
902 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
903 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
904 		goto dont_reorder;
905 
906 	/* not actually part of this BA session */
907 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
908 		goto dont_reorder;
909 
910 	/* new, potentially un-ordered, ampdu frame - process it */
911 
912 	/* reset session timer */
913 	if (tid_agg_rx->timeout)
914 		tid_agg_rx->last_rx = jiffies;
915 
916 	/* if this mpdu is fragmented - terminate rx aggregation session */
917 	sc = le16_to_cpu(hdr->seq_ctrl);
918 	if (sc & IEEE80211_SCTL_FRAG) {
919 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
920 		skb_queue_tail(&rx->sdata->skb_queue, skb);
921 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
922 		return;
923 	}
924 
925 	/*
926 	 * No locking needed -- we will only ever process one
927 	 * RX packet at a time, and thus own tid_agg_rx. All
928 	 * other code manipulating it needs to (and does) make
929 	 * sure that we cannot get to it any more before doing
930 	 * anything with it.
931 	 */
932 	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
933 					     frames))
934 		return;
935 
936  dont_reorder:
937 	__skb_queue_tail(frames, skb);
938 }
939 
940 static ieee80211_rx_result debug_noinline
941 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
942 {
943 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
944 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
945 
946 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
947 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
948 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
949 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
950 			     hdr->seq_ctrl)) {
951 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
952 				rx->local->dot11FrameDuplicateCount++;
953 				rx->sta->num_duplicates++;
954 			}
955 			return RX_DROP_UNUSABLE;
956 		} else
957 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
958 	}
959 
960 	if (unlikely(rx->skb->len < 16)) {
961 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
962 		return RX_DROP_MONITOR;
963 	}
964 
965 	/* Drop disallowed frame classes based on STA auth/assoc state;
966 	 * IEEE 802.11, Chap 5.5.
967 	 *
968 	 * mac80211 filters only based on association state, i.e. it drops
969 	 * Class 3 frames from not associated stations. hostapd sends
970 	 * deauth/disassoc frames when needed. In addition, hostapd is
971 	 * responsible for filtering on both auth and assoc states.
972 	 */
973 
974 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
975 		return ieee80211_rx_mesh_check(rx);
976 
977 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
978 		      ieee80211_is_pspoll(hdr->frame_control)) &&
979 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
980 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
981 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
982 		/*
983 		 * accept port control frames from the AP even when it's not
984 		 * yet marked ASSOC to prevent a race where we don't set the
985 		 * assoc bit quickly enough before it sends the first frame
986 		 */
987 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
988 		    ieee80211_is_data_present(hdr->frame_control)) {
989 			unsigned int hdrlen;
990 			__be16 ethertype;
991 
992 			hdrlen = ieee80211_hdrlen(hdr->frame_control);
993 
994 			if (rx->skb->len < hdrlen + 8)
995 				return RX_DROP_MONITOR;
996 
997 			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
998 			if (ethertype == rx->sdata->control_port_protocol)
999 				return RX_CONTINUE;
1000 		}
1001 
1002 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1003 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
1004 					       hdr->addr2,
1005 					       GFP_ATOMIC))
1006 			return RX_DROP_UNUSABLE;
1007 
1008 		return RX_DROP_MONITOR;
1009 	}
1010 
1011 	return RX_CONTINUE;
1012 }
1013 
1014 
1015 static ieee80211_rx_result debug_noinline
1016 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1017 {
1018 	struct sk_buff *skb = rx->skb;
1019 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1020 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1021 	int keyidx;
1022 	int hdrlen;
1023 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
1024 	struct ieee80211_key *sta_ptk = NULL;
1025 	int mmie_keyidx = -1;
1026 	__le16 fc;
1027 
1028 	/*
1029 	 * Key selection 101
1030 	 *
1031 	 * There are four types of keys:
1032 	 *  - GTK (group keys)
1033 	 *  - IGTK (group keys for management frames)
1034 	 *  - PTK (pairwise keys)
1035 	 *  - STK (station-to-station pairwise keys)
1036 	 *
1037 	 * When selecting a key, we have to distinguish between multicast
1038 	 * (including broadcast) and unicast frames, the latter can only
1039 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
1040 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1041 	 * unicast frames can also use key indices like GTKs. Hence, if we
1042 	 * don't have a PTK/STK we check the key index for a WEP key.
1043 	 *
1044 	 * Note that in a regular BSS, multicast frames are sent by the
1045 	 * AP only, associated stations unicast the frame to the AP first
1046 	 * which then multicasts it on their behalf.
1047 	 *
1048 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
1049 	 * with each station, that is something we don't currently handle.
1050 	 * The spec seems to expect that one negotiates the same key with
1051 	 * every station but there's no such requirement; VLANs could be
1052 	 * possible.
1053 	 */
1054 
1055 	/*
1056 	 * No point in finding a key and decrypting if the frame is neither
1057 	 * addressed to us nor a multicast frame.
1058 	 */
1059 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1060 		return RX_CONTINUE;
1061 
1062 	/* start without a key */
1063 	rx->key = NULL;
1064 
1065 	if (rx->sta)
1066 		sta_ptk = rcu_dereference(rx->sta->ptk);
1067 
1068 	fc = hdr->frame_control;
1069 
1070 	if (!ieee80211_has_protected(fc))
1071 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1072 
1073 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1074 		rx->key = sta_ptk;
1075 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1076 		    (status->flag & RX_FLAG_IV_STRIPPED))
1077 			return RX_CONTINUE;
1078 		/* Skip decryption if the frame is not protected. */
1079 		if (!ieee80211_has_protected(fc))
1080 			return RX_CONTINUE;
1081 	} else if (mmie_keyidx >= 0) {
1082 		/* Broadcast/multicast robust management frame / BIP */
1083 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1084 		    (status->flag & RX_FLAG_IV_STRIPPED))
1085 			return RX_CONTINUE;
1086 
1087 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1088 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1089 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1090 		if (rx->sta)
1091 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1092 		if (!rx->key)
1093 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1094 	} else if (!ieee80211_has_protected(fc)) {
1095 		/*
1096 		 * The frame was not protected, so skip decryption. However, we
1097 		 * need to set rx->key if there is a key that could have been
1098 		 * used so that the frame may be dropped if encryption would
1099 		 * have been expected.
1100 		 */
1101 		struct ieee80211_key *key = NULL;
1102 		struct ieee80211_sub_if_data *sdata = rx->sdata;
1103 		int i;
1104 
1105 		if (ieee80211_is_mgmt(fc) &&
1106 		    is_multicast_ether_addr(hdr->addr1) &&
1107 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1108 			rx->key = key;
1109 		else {
1110 			if (rx->sta) {
1111 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1112 					key = rcu_dereference(rx->sta->gtk[i]);
1113 					if (key)
1114 						break;
1115 				}
1116 			}
1117 			if (!key) {
1118 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1119 					key = rcu_dereference(sdata->keys[i]);
1120 					if (key)
1121 						break;
1122 				}
1123 			}
1124 			if (key)
1125 				rx->key = key;
1126 		}
1127 		return RX_CONTINUE;
1128 	} else {
1129 		u8 keyid;
1130 		/*
1131 		 * The device doesn't give us the IV so we won't be
1132 		 * able to look up the key. That's ok though, we
1133 		 * don't need to decrypt the frame, we just won't
1134 		 * be able to keep statistics accurate.
1135 		 * Except for key threshold notifications, should
1136 		 * we somehow allow the driver to tell us which key
1137 		 * the hardware used if this flag is set?
1138 		 */
1139 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1140 		    (status->flag & RX_FLAG_IV_STRIPPED))
1141 			return RX_CONTINUE;
1142 
1143 		hdrlen = ieee80211_hdrlen(fc);
1144 
1145 		if (rx->skb->len < 8 + hdrlen)
1146 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1147 
1148 		/*
1149 		 * no need to call ieee80211_wep_get_keyidx,
1150 		 * it verifies a bunch of things we've done already
1151 		 */
1152 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1153 		keyidx = keyid >> 6;
1154 
1155 		/* check per-station GTK first, if multicast packet */
1156 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1157 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1158 
1159 		/* if not found, try default key */
1160 		if (!rx->key) {
1161 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1162 
1163 			/*
1164 			 * RSNA-protected unicast frames should always be
1165 			 * sent with pairwise or station-to-station keys,
1166 			 * but for WEP we allow using a key index as well.
1167 			 */
1168 			if (rx->key &&
1169 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1170 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1171 			    !is_multicast_ether_addr(hdr->addr1))
1172 				rx->key = NULL;
1173 		}
1174 	}
1175 
1176 	if (rx->key) {
1177 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1178 			return RX_DROP_MONITOR;
1179 
1180 		rx->key->tx_rx_count++;
1181 		/* TODO: add threshold stuff again */
1182 	} else {
1183 		return RX_DROP_MONITOR;
1184 	}
1185 
1186 	switch (rx->key->conf.cipher) {
1187 	case WLAN_CIPHER_SUITE_WEP40:
1188 	case WLAN_CIPHER_SUITE_WEP104:
1189 		result = ieee80211_crypto_wep_decrypt(rx);
1190 		break;
1191 	case WLAN_CIPHER_SUITE_TKIP:
1192 		result = ieee80211_crypto_tkip_decrypt(rx);
1193 		break;
1194 	case WLAN_CIPHER_SUITE_CCMP:
1195 		result = ieee80211_crypto_ccmp_decrypt(rx);
1196 		break;
1197 	case WLAN_CIPHER_SUITE_AES_CMAC:
1198 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1199 		break;
1200 	default:
1201 		/*
1202 		 * We can reach here only with HW-only algorithms
1203 		 * but why didn't it decrypt the frame?!
1204 		 */
1205 		return RX_DROP_UNUSABLE;
1206 	}
1207 
1208 	/* the hdr variable is invalid after the decrypt handlers */
1209 
1210 	/* either the frame has been decrypted or will be dropped */
1211 	status->flag |= RX_FLAG_DECRYPTED;
1212 
1213 	return result;
1214 }
1215 
1216 static ieee80211_rx_result debug_noinline
1217 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1218 {
1219 	struct ieee80211_local *local;
1220 	struct ieee80211_hdr *hdr;
1221 	struct sk_buff *skb;
1222 
1223 	local = rx->local;
1224 	skb = rx->skb;
1225 	hdr = (struct ieee80211_hdr *) skb->data;
1226 
1227 	if (!local->pspolling)
1228 		return RX_CONTINUE;
1229 
1230 	if (!ieee80211_has_fromds(hdr->frame_control))
1231 		/* this is not from AP */
1232 		return RX_CONTINUE;
1233 
1234 	if (!ieee80211_is_data(hdr->frame_control))
1235 		return RX_CONTINUE;
1236 
1237 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1238 		/* AP has no more frames buffered for us */
1239 		local->pspolling = false;
1240 		return RX_CONTINUE;
1241 	}
1242 
1243 	/* more data bit is set, let's request a new frame from the AP */
1244 	ieee80211_send_pspoll(local, rx->sdata);
1245 
1246 	return RX_CONTINUE;
1247 }
1248 
1249 static void sta_ps_start(struct sta_info *sta)
1250 {
1251 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1252 	struct ieee80211_local *local = sdata->local;
1253 	struct ps_data *ps;
1254 
1255 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1256 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1257 		ps = &sdata->bss->ps;
1258 	else
1259 		return;
1260 
1261 	atomic_inc(&ps->num_sta_ps);
1262 	set_sta_flag(sta, WLAN_STA_PS_STA);
1263 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1264 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1265 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1266 	       sta->sta.addr, sta->sta.aid);
1267 }
1268 
1269 static void sta_ps_end(struct sta_info *sta)
1270 {
1271 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1272 	       sta->sta.addr, sta->sta.aid);
1273 
1274 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1275 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1276 		       sta->sta.addr, sta->sta.aid);
1277 		return;
1278 	}
1279 
1280 	ieee80211_sta_ps_deliver_wakeup(sta);
1281 }
1282 
1283 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1284 {
1285 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1286 	bool in_ps;
1287 
1288 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1289 
1290 	/* Don't let the same PS state be set twice */
1291 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1292 	if ((start && in_ps) || (!start && !in_ps))
1293 		return -EINVAL;
1294 
1295 	if (start)
1296 		sta_ps_start(sta_inf);
1297 	else
1298 		sta_ps_end(sta_inf);
1299 
1300 	return 0;
1301 }
1302 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1303 
1304 static ieee80211_rx_result debug_noinline
1305 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1306 {
1307 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1308 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1309 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1310 	int tid, ac;
1311 
1312 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1313 		return RX_CONTINUE;
1314 
1315 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1316 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1317 		return RX_CONTINUE;
1318 
1319 	/*
1320 	 * The device handles station powersave, so don't do anything about
1321 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1322 	 * it to mac80211 since they're handled.)
1323 	 */
1324 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1325 		return RX_CONTINUE;
1326 
1327 	/*
1328 	 * Don't do anything if the station isn't already asleep. In
1329 	 * the uAPSD case, the station will probably be marked asleep,
1330 	 * in the PS-Poll case the station must be confused ...
1331 	 */
1332 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1333 		return RX_CONTINUE;
1334 
1335 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1336 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1337 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1338 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1339 			else
1340 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1341 		}
1342 
1343 		/* Free PS Poll skb here instead of returning RX_DROP that would
1344 		 * count as an dropped frame. */
1345 		dev_kfree_skb(rx->skb);
1346 
1347 		return RX_QUEUED;
1348 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1349 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1350 		   ieee80211_has_pm(hdr->frame_control) &&
1351 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1352 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1353 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1354 		ac = ieee802_1d_to_ac[tid & 7];
1355 
1356 		/*
1357 		 * If this AC is not trigger-enabled do nothing.
1358 		 *
1359 		 * NB: This could/should check a separate bitmap of trigger-
1360 		 * enabled queues, but for now we only implement uAPSD w/o
1361 		 * TSPEC changes to the ACs, so they're always the same.
1362 		 */
1363 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1364 			return RX_CONTINUE;
1365 
1366 		/* if we are in a service period, do nothing */
1367 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1368 			return RX_CONTINUE;
1369 
1370 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1371 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1372 		else
1373 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1374 	}
1375 
1376 	return RX_CONTINUE;
1377 }
1378 
1379 static ieee80211_rx_result debug_noinline
1380 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1381 {
1382 	struct sta_info *sta = rx->sta;
1383 	struct sk_buff *skb = rx->skb;
1384 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1385 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1386 
1387 	if (!sta)
1388 		return RX_CONTINUE;
1389 
1390 	/*
1391 	 * Update last_rx only for IBSS packets which are for the current
1392 	 * BSSID and for station already AUTHORIZED to avoid keeping the
1393 	 * current IBSS network alive in cases where other STAs start
1394 	 * using different BSSID. This will also give the station another
1395 	 * chance to restart the authentication/authorization in case
1396 	 * something went wrong the first time.
1397 	 */
1398 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1399 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1400 						NL80211_IFTYPE_ADHOC);
1401 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1402 		    test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1403 			sta->last_rx = jiffies;
1404 			if (ieee80211_is_data(hdr->frame_control)) {
1405 				sta->last_rx_rate_idx = status->rate_idx;
1406 				sta->last_rx_rate_flag = status->flag;
1407 				sta->last_rx_rate_vht_nss = status->vht_nss;
1408 			}
1409 		}
1410 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1411 		/*
1412 		 * Mesh beacons will update last_rx when if they are found to
1413 		 * match the current local configuration when processed.
1414 		 */
1415 		sta->last_rx = jiffies;
1416 		if (ieee80211_is_data(hdr->frame_control)) {
1417 			sta->last_rx_rate_idx = status->rate_idx;
1418 			sta->last_rx_rate_flag = status->flag;
1419 			sta->last_rx_rate_vht_nss = status->vht_nss;
1420 		}
1421 	}
1422 
1423 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1424 		return RX_CONTINUE;
1425 
1426 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1427 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1428 
1429 	sta->rx_fragments++;
1430 	sta->rx_bytes += rx->skb->len;
1431 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1432 		sta->last_signal = status->signal;
1433 		ewma_add(&sta->avg_signal, -status->signal);
1434 	}
1435 
1436 	/*
1437 	 * Change STA power saving mode only at the end of a frame
1438 	 * exchange sequence.
1439 	 */
1440 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1441 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1442 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1443 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1444 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1445 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1446 			/*
1447 			 * Ignore doze->wake transitions that are
1448 			 * indicated by non-data frames, the standard
1449 			 * is unclear here, but for example going to
1450 			 * PS mode and then scanning would cause a
1451 			 * doze->wake transition for the probe request,
1452 			 * and that is clearly undesirable.
1453 			 */
1454 			if (ieee80211_is_data(hdr->frame_control) &&
1455 			    !ieee80211_has_pm(hdr->frame_control))
1456 				sta_ps_end(sta);
1457 		} else {
1458 			if (ieee80211_has_pm(hdr->frame_control))
1459 				sta_ps_start(sta);
1460 		}
1461 	}
1462 
1463 	/* mesh power save support */
1464 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1465 		ieee80211_mps_rx_h_sta_process(sta, hdr);
1466 
1467 	/*
1468 	 * Drop (qos-)data::nullfunc frames silently, since they
1469 	 * are used only to control station power saving mode.
1470 	 */
1471 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1472 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1473 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1474 
1475 		/*
1476 		 * If we receive a 4-addr nullfunc frame from a STA
1477 		 * that was not moved to a 4-addr STA vlan yet send
1478 		 * the event to userspace and for older hostapd drop
1479 		 * the frame to the monitor interface.
1480 		 */
1481 		if (ieee80211_has_a4(hdr->frame_control) &&
1482 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1483 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1484 		      !rx->sdata->u.vlan.sta))) {
1485 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1486 				cfg80211_rx_unexpected_4addr_frame(
1487 					rx->sdata->dev, sta->sta.addr,
1488 					GFP_ATOMIC);
1489 			return RX_DROP_MONITOR;
1490 		}
1491 		/*
1492 		 * Update counter and free packet here to avoid
1493 		 * counting this as a dropped packed.
1494 		 */
1495 		sta->rx_packets++;
1496 		dev_kfree_skb(rx->skb);
1497 		return RX_QUEUED;
1498 	}
1499 
1500 	return RX_CONTINUE;
1501 } /* ieee80211_rx_h_sta_process */
1502 
1503 static inline struct ieee80211_fragment_entry *
1504 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1505 			 unsigned int frag, unsigned int seq, int rx_queue,
1506 			 struct sk_buff **skb)
1507 {
1508 	struct ieee80211_fragment_entry *entry;
1509 
1510 	entry = &sdata->fragments[sdata->fragment_next++];
1511 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1512 		sdata->fragment_next = 0;
1513 
1514 	if (!skb_queue_empty(&entry->skb_list))
1515 		__skb_queue_purge(&entry->skb_list);
1516 
1517 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1518 	*skb = NULL;
1519 	entry->first_frag_time = jiffies;
1520 	entry->seq = seq;
1521 	entry->rx_queue = rx_queue;
1522 	entry->last_frag = frag;
1523 	entry->ccmp = 0;
1524 	entry->extra_len = 0;
1525 
1526 	return entry;
1527 }
1528 
1529 static inline struct ieee80211_fragment_entry *
1530 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1531 			  unsigned int frag, unsigned int seq,
1532 			  int rx_queue, struct ieee80211_hdr *hdr)
1533 {
1534 	struct ieee80211_fragment_entry *entry;
1535 	int i, idx;
1536 
1537 	idx = sdata->fragment_next;
1538 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1539 		struct ieee80211_hdr *f_hdr;
1540 
1541 		idx--;
1542 		if (idx < 0)
1543 			idx = IEEE80211_FRAGMENT_MAX - 1;
1544 
1545 		entry = &sdata->fragments[idx];
1546 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1547 		    entry->rx_queue != rx_queue ||
1548 		    entry->last_frag + 1 != frag)
1549 			continue;
1550 
1551 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1552 
1553 		/*
1554 		 * Check ftype and addresses are equal, else check next fragment
1555 		 */
1556 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1557 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1558 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1559 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1560 			continue;
1561 
1562 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1563 			__skb_queue_purge(&entry->skb_list);
1564 			continue;
1565 		}
1566 		return entry;
1567 	}
1568 
1569 	return NULL;
1570 }
1571 
1572 static ieee80211_rx_result debug_noinline
1573 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1574 {
1575 	struct ieee80211_hdr *hdr;
1576 	u16 sc;
1577 	__le16 fc;
1578 	unsigned int frag, seq;
1579 	struct ieee80211_fragment_entry *entry;
1580 	struct sk_buff *skb;
1581 	struct ieee80211_rx_status *status;
1582 
1583 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1584 	fc = hdr->frame_control;
1585 
1586 	if (ieee80211_is_ctl(fc))
1587 		return RX_CONTINUE;
1588 
1589 	sc = le16_to_cpu(hdr->seq_ctrl);
1590 	frag = sc & IEEE80211_SCTL_FRAG;
1591 
1592 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1593 		   is_multicast_ether_addr(hdr->addr1))) {
1594 		/* not fragmented */
1595 		goto out;
1596 	}
1597 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1598 
1599 	if (skb_linearize(rx->skb))
1600 		return RX_DROP_UNUSABLE;
1601 
1602 	/*
1603 	 *  skb_linearize() might change the skb->data and
1604 	 *  previously cached variables (in this case, hdr) need to
1605 	 *  be refreshed with the new data.
1606 	 */
1607 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1608 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1609 
1610 	if (frag == 0) {
1611 		/* This is the first fragment of a new frame. */
1612 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1613 						 rx->seqno_idx, &(rx->skb));
1614 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1615 		    ieee80211_has_protected(fc)) {
1616 			int queue = rx->security_idx;
1617 			/* Store CCMP PN so that we can verify that the next
1618 			 * fragment has a sequential PN value. */
1619 			entry->ccmp = 1;
1620 			memcpy(entry->last_pn,
1621 			       rx->key->u.ccmp.rx_pn[queue],
1622 			       CCMP_PN_LEN);
1623 		}
1624 		return RX_QUEUED;
1625 	}
1626 
1627 	/* This is a fragment for a frame that should already be pending in
1628 	 * fragment cache. Add this fragment to the end of the pending entry.
1629 	 */
1630 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1631 					  rx->seqno_idx, hdr);
1632 	if (!entry) {
1633 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1634 		return RX_DROP_MONITOR;
1635 	}
1636 
1637 	/* Verify that MPDUs within one MSDU have sequential PN values.
1638 	 * (IEEE 802.11i, 8.3.3.4.5) */
1639 	if (entry->ccmp) {
1640 		int i;
1641 		u8 pn[CCMP_PN_LEN], *rpn;
1642 		int queue;
1643 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1644 			return RX_DROP_UNUSABLE;
1645 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1646 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1647 			pn[i]++;
1648 			if (pn[i])
1649 				break;
1650 		}
1651 		queue = rx->security_idx;
1652 		rpn = rx->key->u.ccmp.rx_pn[queue];
1653 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1654 			return RX_DROP_UNUSABLE;
1655 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1656 	}
1657 
1658 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1659 	__skb_queue_tail(&entry->skb_list, rx->skb);
1660 	entry->last_frag = frag;
1661 	entry->extra_len += rx->skb->len;
1662 	if (ieee80211_has_morefrags(fc)) {
1663 		rx->skb = NULL;
1664 		return RX_QUEUED;
1665 	}
1666 
1667 	rx->skb = __skb_dequeue(&entry->skb_list);
1668 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1669 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1670 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1671 					      GFP_ATOMIC))) {
1672 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1673 			__skb_queue_purge(&entry->skb_list);
1674 			return RX_DROP_UNUSABLE;
1675 		}
1676 	}
1677 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1678 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1679 		dev_kfree_skb(skb);
1680 	}
1681 
1682 	/* Complete frame has been reassembled - process it now */
1683 	status = IEEE80211_SKB_RXCB(rx->skb);
1684 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1685 
1686  out:
1687 	if (rx->sta)
1688 		rx->sta->rx_packets++;
1689 	if (is_multicast_ether_addr(hdr->addr1))
1690 		rx->local->dot11MulticastReceivedFrameCount++;
1691 	else
1692 		ieee80211_led_rx(rx->local);
1693 	return RX_CONTINUE;
1694 }
1695 
1696 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1697 {
1698 	if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1699 		return -EACCES;
1700 
1701 	return 0;
1702 }
1703 
1704 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1705 {
1706 	struct sk_buff *skb = rx->skb;
1707 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1708 
1709 	/*
1710 	 * Pass through unencrypted frames if the hardware has
1711 	 * decrypted them already.
1712 	 */
1713 	if (status->flag & RX_FLAG_DECRYPTED)
1714 		return 0;
1715 
1716 	/* Drop unencrypted frames if key is set. */
1717 	if (unlikely(!ieee80211_has_protected(fc) &&
1718 		     !ieee80211_is_nullfunc(fc) &&
1719 		     ieee80211_is_data(fc) &&
1720 		     (rx->key || rx->sdata->drop_unencrypted)))
1721 		return -EACCES;
1722 
1723 	return 0;
1724 }
1725 
1726 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1727 {
1728 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1729 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1730 	__le16 fc = hdr->frame_control;
1731 
1732 	/*
1733 	 * Pass through unencrypted frames if the hardware has
1734 	 * decrypted them already.
1735 	 */
1736 	if (status->flag & RX_FLAG_DECRYPTED)
1737 		return 0;
1738 
1739 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1740 		if (unlikely(!ieee80211_has_protected(fc) &&
1741 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1742 			     rx->key)) {
1743 			if (ieee80211_is_deauth(fc))
1744 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1745 							    rx->skb->data,
1746 							    rx->skb->len);
1747 			else if (ieee80211_is_disassoc(fc))
1748 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1749 							      rx->skb->data,
1750 							      rx->skb->len);
1751 			return -EACCES;
1752 		}
1753 		/* BIP does not use Protected field, so need to check MMIE */
1754 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1755 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1756 			if (ieee80211_is_deauth(fc))
1757 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1758 							    rx->skb->data,
1759 							    rx->skb->len);
1760 			else if (ieee80211_is_disassoc(fc))
1761 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1762 							      rx->skb->data,
1763 							      rx->skb->len);
1764 			return -EACCES;
1765 		}
1766 		/*
1767 		 * When using MFP, Action frames are not allowed prior to
1768 		 * having configured keys.
1769 		 */
1770 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1771 			     ieee80211_is_robust_mgmt_frame(
1772 				     (struct ieee80211_hdr *) rx->skb->data)))
1773 			return -EACCES;
1774 	}
1775 
1776 	return 0;
1777 }
1778 
1779 static int
1780 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1781 {
1782 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1783 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1784 	bool check_port_control = false;
1785 	struct ethhdr *ehdr;
1786 	int ret;
1787 
1788 	*port_control = false;
1789 	if (ieee80211_has_a4(hdr->frame_control) &&
1790 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1791 		return -1;
1792 
1793 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1794 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1795 
1796 		if (!sdata->u.mgd.use_4addr)
1797 			return -1;
1798 		else
1799 			check_port_control = true;
1800 	}
1801 
1802 	if (is_multicast_ether_addr(hdr->addr1) &&
1803 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1804 		return -1;
1805 
1806 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1807 	if (ret < 0)
1808 		return ret;
1809 
1810 	ehdr = (struct ethhdr *) rx->skb->data;
1811 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1812 		*port_control = true;
1813 	else if (check_port_control)
1814 		return -1;
1815 
1816 	return 0;
1817 }
1818 
1819 /*
1820  * requires that rx->skb is a frame with ethernet header
1821  */
1822 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1823 {
1824 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1825 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1826 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1827 
1828 	/*
1829 	 * Allow EAPOL frames to us/the PAE group address regardless
1830 	 * of whether the frame was encrypted or not.
1831 	 */
1832 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1833 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1834 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1835 		return true;
1836 
1837 	if (ieee80211_802_1x_port_control(rx) ||
1838 	    ieee80211_drop_unencrypted(rx, fc))
1839 		return false;
1840 
1841 	return true;
1842 }
1843 
1844 /*
1845  * requires that rx->skb is a frame with ethernet header
1846  */
1847 static void
1848 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1849 {
1850 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1851 	struct net_device *dev = sdata->dev;
1852 	struct sk_buff *skb, *xmit_skb;
1853 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1854 	struct sta_info *dsta;
1855 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1856 
1857 	skb = rx->skb;
1858 	xmit_skb = NULL;
1859 
1860 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1861 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1862 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1863 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1864 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1865 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1866 			/*
1867 			 * send multicast frames both to higher layers in
1868 			 * local net stack and back to the wireless medium
1869 			 */
1870 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1871 			if (!xmit_skb)
1872 				net_info_ratelimited("%s: failed to clone multicast frame\n",
1873 						    dev->name);
1874 		} else {
1875 			dsta = sta_info_get(sdata, skb->data);
1876 			if (dsta) {
1877 				/*
1878 				 * The destination station is associated to
1879 				 * this AP (in this VLAN), so send the frame
1880 				 * directly to it and do not pass it to local
1881 				 * net stack.
1882 				 */
1883 				xmit_skb = skb;
1884 				skb = NULL;
1885 			}
1886 		}
1887 	}
1888 
1889 	if (skb) {
1890 		int align __maybe_unused;
1891 
1892 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1893 		/*
1894 		 * 'align' will only take the values 0 or 2 here
1895 		 * since all frames are required to be aligned
1896 		 * to 2-byte boundaries when being passed to
1897 		 * mac80211. That also explains the __skb_push()
1898 		 * below.
1899 		 */
1900 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1901 		if (align) {
1902 			if (WARN_ON(skb_headroom(skb) < 3)) {
1903 				dev_kfree_skb(skb);
1904 				skb = NULL;
1905 			} else {
1906 				u8 *data = skb->data;
1907 				size_t len = skb_headlen(skb);
1908 				skb->data -= align;
1909 				memmove(skb->data, data, len);
1910 				skb_set_tail_pointer(skb, len);
1911 			}
1912 		}
1913 #endif
1914 
1915 		if (skb) {
1916 			/* deliver to local stack */
1917 			skb->protocol = eth_type_trans(skb, dev);
1918 			memset(skb->cb, 0, sizeof(skb->cb));
1919 			netif_receive_skb(skb);
1920 		}
1921 	}
1922 
1923 	if (xmit_skb) {
1924 		/*
1925 		 * Send to wireless media and increase priority by 256 to
1926 		 * keep the received priority instead of reclassifying
1927 		 * the frame (see cfg80211_classify8021d).
1928 		 */
1929 		xmit_skb->priority += 256;
1930 		xmit_skb->protocol = htons(ETH_P_802_3);
1931 		skb_reset_network_header(xmit_skb);
1932 		skb_reset_mac_header(xmit_skb);
1933 		dev_queue_xmit(xmit_skb);
1934 	}
1935 }
1936 
1937 static ieee80211_rx_result debug_noinline
1938 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1939 {
1940 	struct net_device *dev = rx->sdata->dev;
1941 	struct sk_buff *skb = rx->skb;
1942 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1943 	__le16 fc = hdr->frame_control;
1944 	struct sk_buff_head frame_list;
1945 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1946 
1947 	if (unlikely(!ieee80211_is_data(fc)))
1948 		return RX_CONTINUE;
1949 
1950 	if (unlikely(!ieee80211_is_data_present(fc)))
1951 		return RX_DROP_MONITOR;
1952 
1953 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1954 		return RX_CONTINUE;
1955 
1956 	if (ieee80211_has_a4(hdr->frame_control) &&
1957 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1958 	    !rx->sdata->u.vlan.sta)
1959 		return RX_DROP_UNUSABLE;
1960 
1961 	if (is_multicast_ether_addr(hdr->addr1) &&
1962 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1963 	      rx->sdata->u.vlan.sta) ||
1964 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1965 	      rx->sdata->u.mgd.use_4addr)))
1966 		return RX_DROP_UNUSABLE;
1967 
1968 	skb->dev = dev;
1969 	__skb_queue_head_init(&frame_list);
1970 
1971 	if (skb_linearize(skb))
1972 		return RX_DROP_UNUSABLE;
1973 
1974 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1975 				 rx->sdata->vif.type,
1976 				 rx->local->hw.extra_tx_headroom, true);
1977 
1978 	while (!skb_queue_empty(&frame_list)) {
1979 		rx->skb = __skb_dequeue(&frame_list);
1980 
1981 		if (!ieee80211_frame_allowed(rx, fc)) {
1982 			dev_kfree_skb(rx->skb);
1983 			continue;
1984 		}
1985 		dev->stats.rx_packets++;
1986 		dev->stats.rx_bytes += rx->skb->len;
1987 
1988 		ieee80211_deliver_skb(rx);
1989 	}
1990 
1991 	return RX_QUEUED;
1992 }
1993 
1994 #ifdef CONFIG_MAC80211_MESH
1995 static ieee80211_rx_result
1996 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1997 {
1998 	struct ieee80211_hdr *fwd_hdr, *hdr;
1999 	struct ieee80211_tx_info *info;
2000 	struct ieee80211s_hdr *mesh_hdr;
2001 	struct sk_buff *skb = rx->skb, *fwd_skb;
2002 	struct ieee80211_local *local = rx->local;
2003 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2004 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2005 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2006 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
2007 	u16 q, hdrlen;
2008 
2009 	hdr = (struct ieee80211_hdr *) skb->data;
2010 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
2011 
2012 	/* make sure fixed part of mesh header is there, also checks skb len */
2013 	if (!pskb_may_pull(rx->skb, hdrlen + 6))
2014 		return RX_DROP_MONITOR;
2015 
2016 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2017 
2018 	/* make sure full mesh header is there, also checks skb len */
2019 	if (!pskb_may_pull(rx->skb,
2020 			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2021 		return RX_DROP_MONITOR;
2022 
2023 	/* reload pointers */
2024 	hdr = (struct ieee80211_hdr *) skb->data;
2025 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2026 
2027 	/* frame is in RMC, don't forward */
2028 	if (ieee80211_is_data(hdr->frame_control) &&
2029 	    is_multicast_ether_addr(hdr->addr1) &&
2030 	    mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2031 		return RX_DROP_MONITOR;
2032 
2033 	if (!ieee80211_is_data(hdr->frame_control) ||
2034 	    !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2035 		return RX_CONTINUE;
2036 
2037 	if (!mesh_hdr->ttl)
2038 		return RX_DROP_MONITOR;
2039 
2040 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
2041 		struct mesh_path *mppath;
2042 		char *proxied_addr;
2043 		char *mpp_addr;
2044 
2045 		if (is_multicast_ether_addr(hdr->addr1)) {
2046 			mpp_addr = hdr->addr3;
2047 			proxied_addr = mesh_hdr->eaddr1;
2048 		} else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2049 			/* has_a4 already checked in ieee80211_rx_mesh_check */
2050 			mpp_addr = hdr->addr4;
2051 			proxied_addr = mesh_hdr->eaddr2;
2052 		} else {
2053 			return RX_DROP_MONITOR;
2054 		}
2055 
2056 		rcu_read_lock();
2057 		mppath = mpp_path_lookup(sdata, proxied_addr);
2058 		if (!mppath) {
2059 			mpp_path_add(sdata, proxied_addr, mpp_addr);
2060 		} else {
2061 			spin_lock_bh(&mppath->state_lock);
2062 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
2063 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2064 			spin_unlock_bh(&mppath->state_lock);
2065 		}
2066 		rcu_read_unlock();
2067 	}
2068 
2069 	/* Frame has reached destination.  Don't forward */
2070 	if (!is_multicast_ether_addr(hdr->addr1) &&
2071 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
2072 		return RX_CONTINUE;
2073 
2074 	q = ieee80211_select_queue_80211(sdata, skb, hdr);
2075 	if (ieee80211_queue_stopped(&local->hw, q)) {
2076 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2077 		return RX_DROP_MONITOR;
2078 	}
2079 	skb_set_queue_mapping(skb, q);
2080 
2081 	if (!--mesh_hdr->ttl) {
2082 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2083 		goto out;
2084 	}
2085 
2086 	if (!ifmsh->mshcfg.dot11MeshForwarding)
2087 		goto out;
2088 
2089 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
2090 	if (!fwd_skb) {
2091 		net_info_ratelimited("%s: failed to clone mesh frame\n",
2092 				    sdata->name);
2093 		goto out;
2094 	}
2095 
2096 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2097 	info = IEEE80211_SKB_CB(fwd_skb);
2098 	memset(info, 0, sizeof(*info));
2099 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2100 	info->control.vif = &rx->sdata->vif;
2101 	info->control.jiffies = jiffies;
2102 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2103 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2104 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2105 		/* update power mode indication when forwarding */
2106 		ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2107 	} else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2108 		/* mesh power mode flags updated in mesh_nexthop_lookup */
2109 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2110 	} else {
2111 		/* unable to resolve next hop */
2112 		mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2113 				   fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2114 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2115 		kfree_skb(fwd_skb);
2116 		return RX_DROP_MONITOR;
2117 	}
2118 
2119 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2120 	ieee80211_add_pending_skb(local, fwd_skb);
2121  out:
2122 	if (is_multicast_ether_addr(hdr->addr1) ||
2123 	    sdata->dev->flags & IFF_PROMISC)
2124 		return RX_CONTINUE;
2125 	else
2126 		return RX_DROP_MONITOR;
2127 }
2128 #endif
2129 
2130 static ieee80211_rx_result debug_noinline
2131 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2132 {
2133 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2134 	struct ieee80211_local *local = rx->local;
2135 	struct net_device *dev = sdata->dev;
2136 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2137 	__le16 fc = hdr->frame_control;
2138 	bool port_control;
2139 	int err;
2140 
2141 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2142 		return RX_CONTINUE;
2143 
2144 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2145 		return RX_DROP_MONITOR;
2146 
2147 	/*
2148 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2149 	 * also drop the frame to cooked monitor interfaces.
2150 	 */
2151 	if (ieee80211_has_a4(hdr->frame_control) &&
2152 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2153 		if (rx->sta &&
2154 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2155 			cfg80211_rx_unexpected_4addr_frame(
2156 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2157 		return RX_DROP_MONITOR;
2158 	}
2159 
2160 	err = __ieee80211_data_to_8023(rx, &port_control);
2161 	if (unlikely(err))
2162 		return RX_DROP_UNUSABLE;
2163 
2164 	if (!ieee80211_frame_allowed(rx, fc))
2165 		return RX_DROP_MONITOR;
2166 
2167 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2168 	    unlikely(port_control) && sdata->bss) {
2169 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2170 				     u.ap);
2171 		dev = sdata->dev;
2172 		rx->sdata = sdata;
2173 	}
2174 
2175 	rx->skb->dev = dev;
2176 
2177 	dev->stats.rx_packets++;
2178 	dev->stats.rx_bytes += rx->skb->len;
2179 
2180 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2181 	    !is_multicast_ether_addr(
2182 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2183 	    (!local->scanning &&
2184 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2185 			mod_timer(&local->dynamic_ps_timer, jiffies +
2186 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2187 	}
2188 
2189 	ieee80211_deliver_skb(rx);
2190 
2191 	return RX_QUEUED;
2192 }
2193 
2194 static ieee80211_rx_result debug_noinline
2195 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2196 {
2197 	struct sk_buff *skb = rx->skb;
2198 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2199 	struct tid_ampdu_rx *tid_agg_rx;
2200 	u16 start_seq_num;
2201 	u16 tid;
2202 
2203 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2204 		return RX_CONTINUE;
2205 
2206 	if (ieee80211_is_back_req(bar->frame_control)) {
2207 		struct {
2208 			__le16 control, start_seq_num;
2209 		} __packed bar_data;
2210 
2211 		if (!rx->sta)
2212 			return RX_DROP_MONITOR;
2213 
2214 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2215 				  &bar_data, sizeof(bar_data)))
2216 			return RX_DROP_MONITOR;
2217 
2218 		tid = le16_to_cpu(bar_data.control) >> 12;
2219 
2220 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2221 		if (!tid_agg_rx)
2222 			return RX_DROP_MONITOR;
2223 
2224 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2225 
2226 		/* reset session timer */
2227 		if (tid_agg_rx->timeout)
2228 			mod_timer(&tid_agg_rx->session_timer,
2229 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2230 
2231 		spin_lock(&tid_agg_rx->reorder_lock);
2232 		/* release stored frames up to start of BAR */
2233 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2234 						 start_seq_num, frames);
2235 		spin_unlock(&tid_agg_rx->reorder_lock);
2236 
2237 		kfree_skb(skb);
2238 		return RX_QUEUED;
2239 	}
2240 
2241 	/*
2242 	 * After this point, we only want management frames,
2243 	 * so we can drop all remaining control frames to
2244 	 * cooked monitor interfaces.
2245 	 */
2246 	return RX_DROP_MONITOR;
2247 }
2248 
2249 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2250 					   struct ieee80211_mgmt *mgmt,
2251 					   size_t len)
2252 {
2253 	struct ieee80211_local *local = sdata->local;
2254 	struct sk_buff *skb;
2255 	struct ieee80211_mgmt *resp;
2256 
2257 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2258 		/* Not to own unicast address */
2259 		return;
2260 	}
2261 
2262 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2263 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2264 		/* Not from the current AP or not associated yet. */
2265 		return;
2266 	}
2267 
2268 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2269 		/* Too short SA Query request frame */
2270 		return;
2271 	}
2272 
2273 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2274 	if (skb == NULL)
2275 		return;
2276 
2277 	skb_reserve(skb, local->hw.extra_tx_headroom);
2278 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2279 	memset(resp, 0, 24);
2280 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2281 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2282 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2283 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2284 					  IEEE80211_STYPE_ACTION);
2285 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2286 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2287 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2288 	memcpy(resp->u.action.u.sa_query.trans_id,
2289 	       mgmt->u.action.u.sa_query.trans_id,
2290 	       WLAN_SA_QUERY_TR_ID_LEN);
2291 
2292 	ieee80211_tx_skb(sdata, skb);
2293 }
2294 
2295 static ieee80211_rx_result debug_noinline
2296 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2297 {
2298 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2299 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2300 
2301 	/*
2302 	 * From here on, look only at management frames.
2303 	 * Data and control frames are already handled,
2304 	 * and unknown (reserved) frames are useless.
2305 	 */
2306 	if (rx->skb->len < 24)
2307 		return RX_DROP_MONITOR;
2308 
2309 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2310 		return RX_DROP_MONITOR;
2311 
2312 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2313 	    ieee80211_is_beacon(mgmt->frame_control) &&
2314 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2315 		int sig = 0;
2316 
2317 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2318 			sig = status->signal;
2319 
2320 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2321 					    rx->skb->data, rx->skb->len,
2322 					    status->freq, sig);
2323 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2324 	}
2325 
2326 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2327 		return RX_DROP_MONITOR;
2328 
2329 	if (ieee80211_drop_unencrypted_mgmt(rx))
2330 		return RX_DROP_UNUSABLE;
2331 
2332 	return RX_CONTINUE;
2333 }
2334 
2335 static ieee80211_rx_result debug_noinline
2336 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2337 {
2338 	struct ieee80211_local *local = rx->local;
2339 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2340 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2341 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2342 	int len = rx->skb->len;
2343 
2344 	if (!ieee80211_is_action(mgmt->frame_control))
2345 		return RX_CONTINUE;
2346 
2347 	/* drop too small frames */
2348 	if (len < IEEE80211_MIN_ACTION_SIZE)
2349 		return RX_DROP_UNUSABLE;
2350 
2351 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2352 	    mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2353 		return RX_DROP_UNUSABLE;
2354 
2355 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2356 		return RX_DROP_UNUSABLE;
2357 
2358 	switch (mgmt->u.action.category) {
2359 	case WLAN_CATEGORY_HT:
2360 		/* reject HT action frames from stations not supporting HT */
2361 		if (!rx->sta->sta.ht_cap.ht_supported)
2362 			goto invalid;
2363 
2364 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2365 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2366 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2367 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2368 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2369 			break;
2370 
2371 		/* verify action & smps_control/chanwidth are present */
2372 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2373 			goto invalid;
2374 
2375 		switch (mgmt->u.action.u.ht_smps.action) {
2376 		case WLAN_HT_ACTION_SMPS: {
2377 			struct ieee80211_supported_band *sband;
2378 			enum ieee80211_smps_mode smps_mode;
2379 
2380 			/* convert to HT capability */
2381 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2382 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2383 				smps_mode = IEEE80211_SMPS_OFF;
2384 				break;
2385 			case WLAN_HT_SMPS_CONTROL_STATIC:
2386 				smps_mode = IEEE80211_SMPS_STATIC;
2387 				break;
2388 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2389 				smps_mode = IEEE80211_SMPS_DYNAMIC;
2390 				break;
2391 			default:
2392 				goto invalid;
2393 			}
2394 
2395 			/* if no change do nothing */
2396 			if (rx->sta->sta.smps_mode == smps_mode)
2397 				goto handled;
2398 			rx->sta->sta.smps_mode = smps_mode;
2399 
2400 			sband = rx->local->hw.wiphy->bands[status->band];
2401 
2402 			rate_control_rate_update(local, sband, rx->sta,
2403 						 IEEE80211_RC_SMPS_CHANGED);
2404 			goto handled;
2405 		}
2406 		case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2407 			struct ieee80211_supported_band *sband;
2408 			u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2409 			enum ieee80211_sta_rx_bandwidth new_bw;
2410 
2411 			/* If it doesn't support 40 MHz it can't change ... */
2412 			if (!(rx->sta->sta.ht_cap.cap &
2413 					IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2414 				goto handled;
2415 
2416 			if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2417 				new_bw = IEEE80211_STA_RX_BW_20;
2418 			else
2419 				new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2420 
2421 			if (rx->sta->sta.bandwidth == new_bw)
2422 				goto handled;
2423 
2424 			sband = rx->local->hw.wiphy->bands[status->band];
2425 
2426 			rate_control_rate_update(local, sband, rx->sta,
2427 						 IEEE80211_RC_BW_CHANGED);
2428 			goto handled;
2429 		}
2430 		default:
2431 			goto invalid;
2432 		}
2433 
2434 		break;
2435 	case WLAN_CATEGORY_VHT:
2436 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2437 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2438 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2439 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2440 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2441 			break;
2442 
2443 		/* verify action code is present */
2444 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2445 			goto invalid;
2446 
2447 		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2448 		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2449 			u8 opmode;
2450 
2451 			/* verify opmode is present */
2452 			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2453 				goto invalid;
2454 
2455 			opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2456 
2457 			ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2458 						    opmode, status->band,
2459 						    false);
2460 			goto handled;
2461 		}
2462 		default:
2463 			break;
2464 		}
2465 		break;
2466 	case WLAN_CATEGORY_BACK:
2467 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2468 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2469 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2470 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2471 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2472 			break;
2473 
2474 		/* verify action_code is present */
2475 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2476 			break;
2477 
2478 		switch (mgmt->u.action.u.addba_req.action_code) {
2479 		case WLAN_ACTION_ADDBA_REQ:
2480 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2481 				   sizeof(mgmt->u.action.u.addba_req)))
2482 				goto invalid;
2483 			break;
2484 		case WLAN_ACTION_ADDBA_RESP:
2485 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2486 				   sizeof(mgmt->u.action.u.addba_resp)))
2487 				goto invalid;
2488 			break;
2489 		case WLAN_ACTION_DELBA:
2490 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2491 				   sizeof(mgmt->u.action.u.delba)))
2492 				goto invalid;
2493 			break;
2494 		default:
2495 			goto invalid;
2496 		}
2497 
2498 		goto queue;
2499 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2500 		if (status->band != IEEE80211_BAND_5GHZ)
2501 			break;
2502 
2503 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2504 			break;
2505 
2506 		/* verify action_code is present */
2507 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2508 			break;
2509 
2510 		switch (mgmt->u.action.u.measurement.action_code) {
2511 		case WLAN_ACTION_SPCT_MSR_REQ:
2512 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2513 				   sizeof(mgmt->u.action.u.measurement)))
2514 				break;
2515 			ieee80211_process_measurement_req(sdata, mgmt, len);
2516 			goto handled;
2517 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2518 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2519 				   sizeof(mgmt->u.action.u.chan_switch)))
2520 				break;
2521 
2522 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2523 				break;
2524 
2525 			if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2526 				break;
2527 
2528 			goto queue;
2529 		}
2530 		break;
2531 	case WLAN_CATEGORY_SA_QUERY:
2532 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2533 			   sizeof(mgmt->u.action.u.sa_query)))
2534 			break;
2535 
2536 		switch (mgmt->u.action.u.sa_query.action) {
2537 		case WLAN_ACTION_SA_QUERY_REQUEST:
2538 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2539 				break;
2540 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2541 			goto handled;
2542 		}
2543 		break;
2544 	case WLAN_CATEGORY_SELF_PROTECTED:
2545 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2546 			   sizeof(mgmt->u.action.u.self_prot.action_code)))
2547 			break;
2548 
2549 		switch (mgmt->u.action.u.self_prot.action_code) {
2550 		case WLAN_SP_MESH_PEERING_OPEN:
2551 		case WLAN_SP_MESH_PEERING_CLOSE:
2552 		case WLAN_SP_MESH_PEERING_CONFIRM:
2553 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2554 				goto invalid;
2555 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2556 				/* userspace handles this frame */
2557 				break;
2558 			goto queue;
2559 		case WLAN_SP_MGK_INFORM:
2560 		case WLAN_SP_MGK_ACK:
2561 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2562 				goto invalid;
2563 			break;
2564 		}
2565 		break;
2566 	case WLAN_CATEGORY_MESH_ACTION:
2567 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2568 			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
2569 			break;
2570 
2571 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2572 			break;
2573 		if (mesh_action_is_path_sel(mgmt) &&
2574 		    !mesh_path_sel_is_hwmp(sdata))
2575 			break;
2576 		goto queue;
2577 	}
2578 
2579 	return RX_CONTINUE;
2580 
2581  invalid:
2582 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2583 	/* will return in the next handlers */
2584 	return RX_CONTINUE;
2585 
2586  handled:
2587 	if (rx->sta)
2588 		rx->sta->rx_packets++;
2589 	dev_kfree_skb(rx->skb);
2590 	return RX_QUEUED;
2591 
2592  queue:
2593 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2594 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2595 	ieee80211_queue_work(&local->hw, &sdata->work);
2596 	if (rx->sta)
2597 		rx->sta->rx_packets++;
2598 	return RX_QUEUED;
2599 }
2600 
2601 static ieee80211_rx_result debug_noinline
2602 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2603 {
2604 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2605 	int sig = 0;
2606 
2607 	/* skip known-bad action frames and return them in the next handler */
2608 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2609 		return RX_CONTINUE;
2610 
2611 	/*
2612 	 * Getting here means the kernel doesn't know how to handle
2613 	 * it, but maybe userspace does ... include returned frames
2614 	 * so userspace can register for those to know whether ones
2615 	 * it transmitted were processed or returned.
2616 	 */
2617 
2618 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2619 		sig = status->signal;
2620 
2621 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2622 			     rx->skb->data, rx->skb->len,
2623 			     GFP_ATOMIC)) {
2624 		if (rx->sta)
2625 			rx->sta->rx_packets++;
2626 		dev_kfree_skb(rx->skb);
2627 		return RX_QUEUED;
2628 	}
2629 
2630 	return RX_CONTINUE;
2631 }
2632 
2633 static ieee80211_rx_result debug_noinline
2634 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2635 {
2636 	struct ieee80211_local *local = rx->local;
2637 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2638 	struct sk_buff *nskb;
2639 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2640 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2641 
2642 	if (!ieee80211_is_action(mgmt->frame_control))
2643 		return RX_CONTINUE;
2644 
2645 	/*
2646 	 * For AP mode, hostapd is responsible for handling any action
2647 	 * frames that we didn't handle, including returning unknown
2648 	 * ones. For all other modes we will return them to the sender,
2649 	 * setting the 0x80 bit in the action category, as required by
2650 	 * 802.11-2012 9.24.4.
2651 	 * Newer versions of hostapd shall also use the management frame
2652 	 * registration mechanisms, but older ones still use cooked
2653 	 * monitor interfaces so push all frames there.
2654 	 */
2655 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2656 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2657 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2658 		return RX_DROP_MONITOR;
2659 
2660 	if (is_multicast_ether_addr(mgmt->da))
2661 		return RX_DROP_MONITOR;
2662 
2663 	/* do not return rejected action frames */
2664 	if (mgmt->u.action.category & 0x80)
2665 		return RX_DROP_UNUSABLE;
2666 
2667 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2668 			       GFP_ATOMIC);
2669 	if (nskb) {
2670 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2671 
2672 		nmgmt->u.action.category |= 0x80;
2673 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2674 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2675 
2676 		memset(nskb->cb, 0, sizeof(nskb->cb));
2677 
2678 		ieee80211_tx_skb(rx->sdata, nskb);
2679 	}
2680 	dev_kfree_skb(rx->skb);
2681 	return RX_QUEUED;
2682 }
2683 
2684 static ieee80211_rx_result debug_noinline
2685 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2686 {
2687 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2688 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2689 	__le16 stype;
2690 
2691 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2692 
2693 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2694 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2695 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2696 		return RX_DROP_MONITOR;
2697 
2698 	switch (stype) {
2699 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2700 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2701 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2702 		/* process for all: mesh, mlme, ibss */
2703 		break;
2704 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2705 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2706 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2707 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2708 		if (is_multicast_ether_addr(mgmt->da) &&
2709 		    !is_broadcast_ether_addr(mgmt->da))
2710 			return RX_DROP_MONITOR;
2711 
2712 		/* process only for station */
2713 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2714 			return RX_DROP_MONITOR;
2715 		break;
2716 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2717 		/* process only for ibss and mesh */
2718 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2719 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2720 			return RX_DROP_MONITOR;
2721 		break;
2722 	default:
2723 		return RX_DROP_MONITOR;
2724 	}
2725 
2726 	/* queue up frame and kick off work to process it */
2727 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2728 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2729 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2730 	if (rx->sta)
2731 		rx->sta->rx_packets++;
2732 
2733 	return RX_QUEUED;
2734 }
2735 
2736 /* TODO: use IEEE80211_RX_FRAGMENTED */
2737 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2738 					struct ieee80211_rate *rate)
2739 {
2740 	struct ieee80211_sub_if_data *sdata;
2741 	struct ieee80211_local *local = rx->local;
2742 	struct sk_buff *skb = rx->skb, *skb2;
2743 	struct net_device *prev_dev = NULL;
2744 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2745 	int needed_headroom;
2746 
2747 	/*
2748 	 * If cooked monitor has been processed already, then
2749 	 * don't do it again. If not, set the flag.
2750 	 */
2751 	if (rx->flags & IEEE80211_RX_CMNTR)
2752 		goto out_free_skb;
2753 	rx->flags |= IEEE80211_RX_CMNTR;
2754 
2755 	/* If there are no cooked monitor interfaces, just free the SKB */
2756 	if (!local->cooked_mntrs)
2757 		goto out_free_skb;
2758 
2759 	/* room for the radiotap header based on driver features */
2760 	needed_headroom = ieee80211_rx_radiotap_space(local, status);
2761 
2762 	if (skb_headroom(skb) < needed_headroom &&
2763 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2764 		goto out_free_skb;
2765 
2766 	/* prepend radiotap information */
2767 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2768 					 false);
2769 
2770 	skb_set_mac_header(skb, 0);
2771 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2772 	skb->pkt_type = PACKET_OTHERHOST;
2773 	skb->protocol = htons(ETH_P_802_2);
2774 
2775 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2776 		if (!ieee80211_sdata_running(sdata))
2777 			continue;
2778 
2779 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2780 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2781 			continue;
2782 
2783 		if (prev_dev) {
2784 			skb2 = skb_clone(skb, GFP_ATOMIC);
2785 			if (skb2) {
2786 				skb2->dev = prev_dev;
2787 				netif_receive_skb(skb2);
2788 			}
2789 		}
2790 
2791 		prev_dev = sdata->dev;
2792 		sdata->dev->stats.rx_packets++;
2793 		sdata->dev->stats.rx_bytes += skb->len;
2794 	}
2795 
2796 	if (prev_dev) {
2797 		skb->dev = prev_dev;
2798 		netif_receive_skb(skb);
2799 		return;
2800 	}
2801 
2802  out_free_skb:
2803 	dev_kfree_skb(skb);
2804 }
2805 
2806 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2807 					 ieee80211_rx_result res)
2808 {
2809 	switch (res) {
2810 	case RX_DROP_MONITOR:
2811 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2812 		if (rx->sta)
2813 			rx->sta->rx_dropped++;
2814 		/* fall through */
2815 	case RX_CONTINUE: {
2816 		struct ieee80211_rate *rate = NULL;
2817 		struct ieee80211_supported_band *sband;
2818 		struct ieee80211_rx_status *status;
2819 
2820 		status = IEEE80211_SKB_RXCB((rx->skb));
2821 
2822 		sband = rx->local->hw.wiphy->bands[status->band];
2823 		if (!(status->flag & RX_FLAG_HT) &&
2824 		    !(status->flag & RX_FLAG_VHT))
2825 			rate = &sband->bitrates[status->rate_idx];
2826 
2827 		ieee80211_rx_cooked_monitor(rx, rate);
2828 		break;
2829 		}
2830 	case RX_DROP_UNUSABLE:
2831 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2832 		if (rx->sta)
2833 			rx->sta->rx_dropped++;
2834 		dev_kfree_skb(rx->skb);
2835 		break;
2836 	case RX_QUEUED:
2837 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2838 		break;
2839 	}
2840 }
2841 
2842 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2843 				  struct sk_buff_head *frames)
2844 {
2845 	ieee80211_rx_result res = RX_DROP_MONITOR;
2846 	struct sk_buff *skb;
2847 
2848 #define CALL_RXH(rxh)			\
2849 	do {				\
2850 		res = rxh(rx);		\
2851 		if (res != RX_CONTINUE)	\
2852 			goto rxh_next;  \
2853 	} while (0);
2854 
2855 	spin_lock_bh(&rx->local->rx_path_lock);
2856 
2857 	while ((skb = __skb_dequeue(frames))) {
2858 		/*
2859 		 * all the other fields are valid across frames
2860 		 * that belong to an aMPDU since they are on the
2861 		 * same TID from the same station
2862 		 */
2863 		rx->skb = skb;
2864 
2865 		CALL_RXH(ieee80211_rx_h_decrypt)
2866 		CALL_RXH(ieee80211_rx_h_check_more_data)
2867 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2868 		CALL_RXH(ieee80211_rx_h_sta_process)
2869 		CALL_RXH(ieee80211_rx_h_defragment)
2870 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2871 		/* must be after MMIC verify so header is counted in MPDU mic */
2872 #ifdef CONFIG_MAC80211_MESH
2873 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2874 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2875 #endif
2876 		CALL_RXH(ieee80211_rx_h_amsdu)
2877 		CALL_RXH(ieee80211_rx_h_data)
2878 
2879 		/* special treatment -- needs the queue */
2880 		res = ieee80211_rx_h_ctrl(rx, frames);
2881 		if (res != RX_CONTINUE)
2882 			goto rxh_next;
2883 
2884 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2885 		CALL_RXH(ieee80211_rx_h_action)
2886 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2887 		CALL_RXH(ieee80211_rx_h_action_return)
2888 		CALL_RXH(ieee80211_rx_h_mgmt)
2889 
2890  rxh_next:
2891 		ieee80211_rx_handlers_result(rx, res);
2892 
2893 #undef CALL_RXH
2894 	}
2895 
2896 	spin_unlock_bh(&rx->local->rx_path_lock);
2897 }
2898 
2899 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2900 {
2901 	struct sk_buff_head reorder_release;
2902 	ieee80211_rx_result res = RX_DROP_MONITOR;
2903 
2904 	__skb_queue_head_init(&reorder_release);
2905 
2906 #define CALL_RXH(rxh)			\
2907 	do {				\
2908 		res = rxh(rx);		\
2909 		if (res != RX_CONTINUE)	\
2910 			goto rxh_next;  \
2911 	} while (0);
2912 
2913 	CALL_RXH(ieee80211_rx_h_check)
2914 
2915 	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2916 
2917 	ieee80211_rx_handlers(rx, &reorder_release);
2918 	return;
2919 
2920  rxh_next:
2921 	ieee80211_rx_handlers_result(rx, res);
2922 
2923 #undef CALL_RXH
2924 }
2925 
2926 /*
2927  * This function makes calls into the RX path, therefore
2928  * it has to be invoked under RCU read lock.
2929  */
2930 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2931 {
2932 	struct sk_buff_head frames;
2933 	struct ieee80211_rx_data rx = {
2934 		.sta = sta,
2935 		.sdata = sta->sdata,
2936 		.local = sta->local,
2937 		/* This is OK -- must be QoS data frame */
2938 		.security_idx = tid,
2939 		.seqno_idx = tid,
2940 		.flags = 0,
2941 	};
2942 	struct tid_ampdu_rx *tid_agg_rx;
2943 
2944 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2945 	if (!tid_agg_rx)
2946 		return;
2947 
2948 	__skb_queue_head_init(&frames);
2949 
2950 	spin_lock(&tid_agg_rx->reorder_lock);
2951 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2952 	spin_unlock(&tid_agg_rx->reorder_lock);
2953 
2954 	ieee80211_rx_handlers(&rx, &frames);
2955 }
2956 
2957 /* main receive path */
2958 
2959 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2960 				struct ieee80211_hdr *hdr)
2961 {
2962 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2963 	struct sk_buff *skb = rx->skb;
2964 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2965 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2966 	int multicast = is_multicast_ether_addr(hdr->addr1);
2967 
2968 	switch (sdata->vif.type) {
2969 	case NL80211_IFTYPE_STATION:
2970 		if (!bssid && !sdata->u.mgd.use_4addr)
2971 			return 0;
2972 		if (!multicast &&
2973 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2974 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2975 			    sdata->u.mgd.use_4addr)
2976 				return 0;
2977 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2978 		}
2979 		break;
2980 	case NL80211_IFTYPE_ADHOC:
2981 		if (!bssid)
2982 			return 0;
2983 		if (ieee80211_is_beacon(hdr->frame_control)) {
2984 			return 1;
2985 		} else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2986 			return 0;
2987 		} else if (!multicast &&
2988 			   !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2989 			if (!(sdata->dev->flags & IFF_PROMISC))
2990 				return 0;
2991 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2992 		} else if (!rx->sta) {
2993 			int rate_idx;
2994 			if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
2995 				rate_idx = 0; /* TODO: HT/VHT rates */
2996 			else
2997 				rate_idx = status->rate_idx;
2998 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2999 						 BIT(rate_idx));
3000 		}
3001 		break;
3002 	case NL80211_IFTYPE_MESH_POINT:
3003 		if (!multicast &&
3004 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3005 			if (!(sdata->dev->flags & IFF_PROMISC))
3006 				return 0;
3007 
3008 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3009 		}
3010 		break;
3011 	case NL80211_IFTYPE_AP_VLAN:
3012 	case NL80211_IFTYPE_AP:
3013 		if (!bssid) {
3014 			if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3015 				return 0;
3016 		} else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3017 			/*
3018 			 * Accept public action frames even when the
3019 			 * BSSID doesn't match, this is used for P2P
3020 			 * and location updates. Note that mac80211
3021 			 * itself never looks at these frames.
3022 			 */
3023 			if (ieee80211_is_public_action(hdr, skb->len))
3024 				return 1;
3025 			if (!ieee80211_is_beacon(hdr->frame_control))
3026 				return 0;
3027 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3028 		}
3029 		break;
3030 	case NL80211_IFTYPE_WDS:
3031 		if (bssid || !ieee80211_is_data(hdr->frame_control))
3032 			return 0;
3033 		if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3034 			return 0;
3035 		break;
3036 	case NL80211_IFTYPE_P2P_DEVICE:
3037 		if (!ieee80211_is_public_action(hdr, skb->len) &&
3038 		    !ieee80211_is_probe_req(hdr->frame_control) &&
3039 		    !ieee80211_is_probe_resp(hdr->frame_control) &&
3040 		    !ieee80211_is_beacon(hdr->frame_control))
3041 			return 0;
3042 		if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3043 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3044 		break;
3045 	default:
3046 		/* should never get here */
3047 		WARN_ON_ONCE(1);
3048 		break;
3049 	}
3050 
3051 	return 1;
3052 }
3053 
3054 /*
3055  * This function returns whether or not the SKB
3056  * was destined for RX processing or not, which,
3057  * if consume is true, is equivalent to whether
3058  * or not the skb was consumed.
3059  */
3060 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3061 					    struct sk_buff *skb, bool consume)
3062 {
3063 	struct ieee80211_local *local = rx->local;
3064 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3065 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3066 	struct ieee80211_hdr *hdr = (void *)skb->data;
3067 	int prepares;
3068 
3069 	rx->skb = skb;
3070 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
3071 	prepares = prepare_for_handlers(rx, hdr);
3072 
3073 	if (!prepares)
3074 		return false;
3075 
3076 	if (!consume) {
3077 		skb = skb_copy(skb, GFP_ATOMIC);
3078 		if (!skb) {
3079 			if (net_ratelimit())
3080 				wiphy_debug(local->hw.wiphy,
3081 					"failed to copy skb for %s\n",
3082 					sdata->name);
3083 			return true;
3084 		}
3085 
3086 		rx->skb = skb;
3087 	}
3088 
3089 	ieee80211_invoke_rx_handlers(rx);
3090 	return true;
3091 }
3092 
3093 /*
3094  * This is the actual Rx frames handler. as it blongs to Rx path it must
3095  * be called with rcu_read_lock protection.
3096  */
3097 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3098 					 struct sk_buff *skb)
3099 {
3100 	struct ieee80211_local *local = hw_to_local(hw);
3101 	struct ieee80211_sub_if_data *sdata;
3102 	struct ieee80211_hdr *hdr;
3103 	__le16 fc;
3104 	struct ieee80211_rx_data rx;
3105 	struct ieee80211_sub_if_data *prev;
3106 	struct sta_info *sta, *tmp, *prev_sta;
3107 	int err = 0;
3108 
3109 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3110 	memset(&rx, 0, sizeof(rx));
3111 	rx.skb = skb;
3112 	rx.local = local;
3113 
3114 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3115 		local->dot11ReceivedFragmentCount++;
3116 
3117 	if (ieee80211_is_mgmt(fc)) {
3118 		/* drop frame if too short for header */
3119 		if (skb->len < ieee80211_hdrlen(fc))
3120 			err = -ENOBUFS;
3121 		else
3122 			err = skb_linearize(skb);
3123 	} else {
3124 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3125 	}
3126 
3127 	if (err) {
3128 		dev_kfree_skb(skb);
3129 		return;
3130 	}
3131 
3132 	hdr = (struct ieee80211_hdr *)skb->data;
3133 	ieee80211_parse_qos(&rx);
3134 	ieee80211_verify_alignment(&rx);
3135 
3136 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3137 		     ieee80211_is_beacon(hdr->frame_control)))
3138 		ieee80211_scan_rx(local, skb);
3139 
3140 	if (ieee80211_is_data(fc)) {
3141 		prev_sta = NULL;
3142 
3143 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
3144 			if (!prev_sta) {
3145 				prev_sta = sta;
3146 				continue;
3147 			}
3148 
3149 			rx.sta = prev_sta;
3150 			rx.sdata = prev_sta->sdata;
3151 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
3152 
3153 			prev_sta = sta;
3154 		}
3155 
3156 		if (prev_sta) {
3157 			rx.sta = prev_sta;
3158 			rx.sdata = prev_sta->sdata;
3159 
3160 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3161 				return;
3162 			goto out;
3163 		}
3164 	}
3165 
3166 	prev = NULL;
3167 
3168 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3169 		if (!ieee80211_sdata_running(sdata))
3170 			continue;
3171 
3172 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3173 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3174 			continue;
3175 
3176 		/*
3177 		 * frame is destined for this interface, but if it's
3178 		 * not also for the previous one we handle that after
3179 		 * the loop to avoid copying the SKB once too much
3180 		 */
3181 
3182 		if (!prev) {
3183 			prev = sdata;
3184 			continue;
3185 		}
3186 
3187 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3188 		rx.sdata = prev;
3189 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
3190 
3191 		prev = sdata;
3192 	}
3193 
3194 	if (prev) {
3195 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3196 		rx.sdata = prev;
3197 
3198 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3199 			return;
3200 	}
3201 
3202  out:
3203 	dev_kfree_skb(skb);
3204 }
3205 
3206 /*
3207  * This is the receive path handler. It is called by a low level driver when an
3208  * 802.11 MPDU is received from the hardware.
3209  */
3210 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3211 {
3212 	struct ieee80211_local *local = hw_to_local(hw);
3213 	struct ieee80211_rate *rate = NULL;
3214 	struct ieee80211_supported_band *sband;
3215 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3216 
3217 	WARN_ON_ONCE(softirq_count() == 0);
3218 
3219 	if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3220 		goto drop;
3221 
3222 	sband = local->hw.wiphy->bands[status->band];
3223 	if (WARN_ON(!sband))
3224 		goto drop;
3225 
3226 	/*
3227 	 * If we're suspending, it is possible although not too likely
3228 	 * that we'd be receiving frames after having already partially
3229 	 * quiesced the stack. We can't process such frames then since
3230 	 * that might, for example, cause stations to be added or other
3231 	 * driver callbacks be invoked.
3232 	 */
3233 	if (unlikely(local->quiescing || local->suspended))
3234 		goto drop;
3235 
3236 	/* We might be during a HW reconfig, prevent Rx for the same reason */
3237 	if (unlikely(local->in_reconfig))
3238 		goto drop;
3239 
3240 	/*
3241 	 * The same happens when we're not even started,
3242 	 * but that's worth a warning.
3243 	 */
3244 	if (WARN_ON(!local->started))
3245 		goto drop;
3246 
3247 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3248 		/*
3249 		 * Validate the rate, unless a PLCP error means that
3250 		 * we probably can't have a valid rate here anyway.
3251 		 */
3252 
3253 		if (status->flag & RX_FLAG_HT) {
3254 			/*
3255 			 * rate_idx is MCS index, which can be [0-76]
3256 			 * as documented on:
3257 			 *
3258 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3259 			 *
3260 			 * Anything else would be some sort of driver or
3261 			 * hardware error. The driver should catch hardware
3262 			 * errors.
3263 			 */
3264 			if (WARN(status->rate_idx > 76,
3265 				 "Rate marked as an HT rate but passed "
3266 				 "status->rate_idx is not "
3267 				 "an MCS index [0-76]: %d (0x%02x)\n",
3268 				 status->rate_idx,
3269 				 status->rate_idx))
3270 				goto drop;
3271 		} else if (status->flag & RX_FLAG_VHT) {
3272 			if (WARN_ONCE(status->rate_idx > 9 ||
3273 				      !status->vht_nss ||
3274 				      status->vht_nss > 8,
3275 				      "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3276 				      status->rate_idx, status->vht_nss))
3277 				goto drop;
3278 		} else {
3279 			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3280 				goto drop;
3281 			rate = &sband->bitrates[status->rate_idx];
3282 		}
3283 	}
3284 
3285 	status->rx_flags = 0;
3286 
3287 	/*
3288 	 * key references and virtual interfaces are protected using RCU
3289 	 * and this requires that we are in a read-side RCU section during
3290 	 * receive processing
3291 	 */
3292 	rcu_read_lock();
3293 
3294 	/*
3295 	 * Frames with failed FCS/PLCP checksum are not returned,
3296 	 * all other frames are returned without radiotap header
3297 	 * if it was previously present.
3298 	 * Also, frames with less than 16 bytes are dropped.
3299 	 */
3300 	skb = ieee80211_rx_monitor(local, skb, rate);
3301 	if (!skb) {
3302 		rcu_read_unlock();
3303 		return;
3304 	}
3305 
3306 	ieee80211_tpt_led_trig_rx(local,
3307 			((struct ieee80211_hdr *)skb->data)->frame_control,
3308 			skb->len);
3309 	__ieee80211_rx_handle_packet(hw, skb);
3310 
3311 	rcu_read_unlock();
3312 
3313 	return;
3314  drop:
3315 	kfree_skb(skb);
3316 }
3317 EXPORT_SYMBOL(ieee80211_rx);
3318 
3319 /* This is a version of the rx handler that can be called from hard irq
3320  * context. Post the skb on the queue and schedule the tasklet */
3321 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3322 {
3323 	struct ieee80211_local *local = hw_to_local(hw);
3324 
3325 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3326 
3327 	skb->pkt_type = IEEE80211_RX_MSG;
3328 	skb_queue_tail(&local->skb_queue, skb);
3329 	tasklet_schedule(&local->tasklet);
3330 }
3331 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3332