xref: /openbmc/linux/net/mac80211/rx.c (revision ee89bd6b)
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 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
652 					    struct tid_ampdu_rx *tid_agg_rx,
653 					    int index,
654 					    struct sk_buff_head *frames)
655 {
656 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
657 	struct ieee80211_rx_status *status;
658 
659 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
660 
661 	if (!skb)
662 		goto no_frame;
663 
664 	/* release the frame from the reorder ring buffer */
665 	tid_agg_rx->stored_mpdu_num--;
666 	tid_agg_rx->reorder_buf[index] = NULL;
667 	status = IEEE80211_SKB_RXCB(skb);
668 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
669 	__skb_queue_tail(frames, skb);
670 
671 no_frame:
672 	tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
673 }
674 
675 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
676 					     struct tid_ampdu_rx *tid_agg_rx,
677 					     u16 head_seq_num,
678 					     struct sk_buff_head *frames)
679 {
680 	int index;
681 
682 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
683 
684 	while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
685 		index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
686 					 tid_agg_rx->ssn) %
687 							tid_agg_rx->buf_size;
688 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
689 						frames);
690 	}
691 }
692 
693 /*
694  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
695  * the skb was added to the buffer longer than this time ago, the earlier
696  * frames that have not yet been received are assumed to be lost and the skb
697  * can be released for processing. This may also release other skb's from the
698  * reorder buffer if there are no additional gaps between the frames.
699  *
700  * Callers must hold tid_agg_rx->reorder_lock.
701  */
702 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
703 
704 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
705 					  struct tid_ampdu_rx *tid_agg_rx,
706 					  struct sk_buff_head *frames)
707 {
708 	int index, j;
709 
710 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
711 
712 	/* release the buffer until next missing frame */
713 	index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
714 				 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
715 	if (!tid_agg_rx->reorder_buf[index] &&
716 	    tid_agg_rx->stored_mpdu_num) {
717 		/*
718 		 * No buffers ready to be released, but check whether any
719 		 * frames in the reorder buffer have timed out.
720 		 */
721 		int skipped = 1;
722 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
723 		     j = (j + 1) % tid_agg_rx->buf_size) {
724 			if (!tid_agg_rx->reorder_buf[j]) {
725 				skipped++;
726 				continue;
727 			}
728 			if (skipped &&
729 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
730 					HT_RX_REORDER_BUF_TIMEOUT))
731 				goto set_release_timer;
732 
733 			ht_dbg_ratelimited(sdata,
734 					   "release an RX reorder frame due to timeout on earlier frames\n");
735 			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
736 							frames);
737 
738 			/*
739 			 * Increment the head seq# also for the skipped slots.
740 			 */
741 			tid_agg_rx->head_seq_num =
742 				(tid_agg_rx->head_seq_num +
743 				 skipped) & IEEE80211_SN_MASK;
744 			skipped = 0;
745 		}
746 	} else while (tid_agg_rx->reorder_buf[index]) {
747 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
748 						frames);
749 		index =	ieee80211_sn_sub(tid_agg_rx->head_seq_num,
750 					 tid_agg_rx->ssn) %
751 							tid_agg_rx->buf_size;
752 	}
753 
754 	if (tid_agg_rx->stored_mpdu_num) {
755 		j = index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
756 					     tid_agg_rx->ssn) %
757 							tid_agg_rx->buf_size;
758 
759 		for (; j != (index - 1) % tid_agg_rx->buf_size;
760 		     j = (j + 1) % tid_agg_rx->buf_size) {
761 			if (tid_agg_rx->reorder_buf[j])
762 				break;
763 		}
764 
765  set_release_timer:
766 
767 		mod_timer(&tid_agg_rx->reorder_timer,
768 			  tid_agg_rx->reorder_time[j] + 1 +
769 			  HT_RX_REORDER_BUF_TIMEOUT);
770 	} else {
771 		del_timer(&tid_agg_rx->reorder_timer);
772 	}
773 }
774 
775 /*
776  * As this function belongs to the RX path it must be under
777  * rcu_read_lock protection. It returns false if the frame
778  * can be processed immediately, true if it was consumed.
779  */
780 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
781 					     struct tid_ampdu_rx *tid_agg_rx,
782 					     struct sk_buff *skb,
783 					     struct sk_buff_head *frames)
784 {
785 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
786 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
787 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
788 	u16 head_seq_num, buf_size;
789 	int index;
790 	bool ret = true;
791 
792 	spin_lock(&tid_agg_rx->reorder_lock);
793 
794 	buf_size = tid_agg_rx->buf_size;
795 	head_seq_num = tid_agg_rx->head_seq_num;
796 
797 	/* frame with out of date sequence number */
798 	if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
799 		dev_kfree_skb(skb);
800 		goto out;
801 	}
802 
803 	/*
804 	 * If frame the sequence number exceeds our buffering window
805 	 * size release some previous frames to make room for this one.
806 	 */
807 	if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
808 		head_seq_num = ieee80211_sn_inc(
809 				ieee80211_sn_sub(mpdu_seq_num, buf_size));
810 		/* release stored frames up to new head to stack */
811 		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
812 						 head_seq_num, frames);
813 	}
814 
815 	/* Now the new frame is always in the range of the reordering buffer */
816 
817 	index = ieee80211_sn_sub(mpdu_seq_num,
818 				 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
819 
820 	/* check if we already stored this frame */
821 	if (tid_agg_rx->reorder_buf[index]) {
822 		dev_kfree_skb(skb);
823 		goto out;
824 	}
825 
826 	/*
827 	 * If the current MPDU is in the right order and nothing else
828 	 * is stored we can process it directly, no need to buffer it.
829 	 * If it is first but there's something stored, we may be able
830 	 * to release frames after this one.
831 	 */
832 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
833 	    tid_agg_rx->stored_mpdu_num == 0) {
834 		tid_agg_rx->head_seq_num =
835 			ieee80211_sn_inc(tid_agg_rx->head_seq_num);
836 		ret = false;
837 		goto out;
838 	}
839 
840 	/* put the frame in the reordering buffer */
841 	tid_agg_rx->reorder_buf[index] = skb;
842 	tid_agg_rx->reorder_time[index] = jiffies;
843 	tid_agg_rx->stored_mpdu_num++;
844 	ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
845 
846  out:
847 	spin_unlock(&tid_agg_rx->reorder_lock);
848 	return ret;
849 }
850 
851 /*
852  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
853  * true if the MPDU was buffered, false if it should be processed.
854  */
855 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
856 				       struct sk_buff_head *frames)
857 {
858 	struct sk_buff *skb = rx->skb;
859 	struct ieee80211_local *local = rx->local;
860 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
861 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
862 	struct sta_info *sta = rx->sta;
863 	struct tid_ampdu_rx *tid_agg_rx;
864 	u16 sc;
865 	u8 tid, ack_policy;
866 
867 	if (!ieee80211_is_data_qos(hdr->frame_control))
868 		goto dont_reorder;
869 
870 	/*
871 	 * filter the QoS data rx stream according to
872 	 * STA/TID and check if this STA/TID is on aggregation
873 	 */
874 
875 	if (!sta)
876 		goto dont_reorder;
877 
878 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
879 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
880 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
881 
882 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
883 	if (!tid_agg_rx)
884 		goto dont_reorder;
885 
886 	/* qos null data frames are excluded */
887 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
888 		goto dont_reorder;
889 
890 	/* not part of a BA session */
891 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
892 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
893 		goto dont_reorder;
894 
895 	/* not actually part of this BA session */
896 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
897 		goto dont_reorder;
898 
899 	/* new, potentially un-ordered, ampdu frame - process it */
900 
901 	/* reset session timer */
902 	if (tid_agg_rx->timeout)
903 		tid_agg_rx->last_rx = jiffies;
904 
905 	/* if this mpdu is fragmented - terminate rx aggregation session */
906 	sc = le16_to_cpu(hdr->seq_ctrl);
907 	if (sc & IEEE80211_SCTL_FRAG) {
908 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
909 		skb_queue_tail(&rx->sdata->skb_queue, skb);
910 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
911 		return;
912 	}
913 
914 	/*
915 	 * No locking needed -- we will only ever process one
916 	 * RX packet at a time, and thus own tid_agg_rx. All
917 	 * other code manipulating it needs to (and does) make
918 	 * sure that we cannot get to it any more before doing
919 	 * anything with it.
920 	 */
921 	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
922 					     frames))
923 		return;
924 
925  dont_reorder:
926 	__skb_queue_tail(frames, skb);
927 }
928 
929 static ieee80211_rx_result debug_noinline
930 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
931 {
932 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
933 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
934 
935 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
936 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
937 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
938 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
939 			     hdr->seq_ctrl)) {
940 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
941 				rx->local->dot11FrameDuplicateCount++;
942 				rx->sta->num_duplicates++;
943 			}
944 			return RX_DROP_UNUSABLE;
945 		} else
946 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
947 	}
948 
949 	if (unlikely(rx->skb->len < 16)) {
950 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
951 		return RX_DROP_MONITOR;
952 	}
953 
954 	/* Drop disallowed frame classes based on STA auth/assoc state;
955 	 * IEEE 802.11, Chap 5.5.
956 	 *
957 	 * mac80211 filters only based on association state, i.e. it drops
958 	 * Class 3 frames from not associated stations. hostapd sends
959 	 * deauth/disassoc frames when needed. In addition, hostapd is
960 	 * responsible for filtering on both auth and assoc states.
961 	 */
962 
963 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
964 		return ieee80211_rx_mesh_check(rx);
965 
966 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
967 		      ieee80211_is_pspoll(hdr->frame_control)) &&
968 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
969 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
970 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
971 		/*
972 		 * accept port control frames from the AP even when it's not
973 		 * yet marked ASSOC to prevent a race where we don't set the
974 		 * assoc bit quickly enough before it sends the first frame
975 		 */
976 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
977 		    ieee80211_is_data_present(hdr->frame_control)) {
978 			unsigned int hdrlen;
979 			__be16 ethertype;
980 
981 			hdrlen = ieee80211_hdrlen(hdr->frame_control);
982 
983 			if (rx->skb->len < hdrlen + 8)
984 				return RX_DROP_MONITOR;
985 
986 			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
987 			if (ethertype == rx->sdata->control_port_protocol)
988 				return RX_CONTINUE;
989 		}
990 
991 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
992 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
993 					       hdr->addr2,
994 					       GFP_ATOMIC))
995 			return RX_DROP_UNUSABLE;
996 
997 		return RX_DROP_MONITOR;
998 	}
999 
1000 	return RX_CONTINUE;
1001 }
1002 
1003 
1004 static ieee80211_rx_result debug_noinline
1005 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1006 {
1007 	struct sk_buff *skb = rx->skb;
1008 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1009 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1010 	int keyidx;
1011 	int hdrlen;
1012 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
1013 	struct ieee80211_key *sta_ptk = NULL;
1014 	int mmie_keyidx = -1;
1015 	__le16 fc;
1016 
1017 	/*
1018 	 * Key selection 101
1019 	 *
1020 	 * There are four types of keys:
1021 	 *  - GTK (group keys)
1022 	 *  - IGTK (group keys for management frames)
1023 	 *  - PTK (pairwise keys)
1024 	 *  - STK (station-to-station pairwise keys)
1025 	 *
1026 	 * When selecting a key, we have to distinguish between multicast
1027 	 * (including broadcast) and unicast frames, the latter can only
1028 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
1029 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1030 	 * unicast frames can also use key indices like GTKs. Hence, if we
1031 	 * don't have a PTK/STK we check the key index for a WEP key.
1032 	 *
1033 	 * Note that in a regular BSS, multicast frames are sent by the
1034 	 * AP only, associated stations unicast the frame to the AP first
1035 	 * which then multicasts it on their behalf.
1036 	 *
1037 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
1038 	 * with each station, that is something we don't currently handle.
1039 	 * The spec seems to expect that one negotiates the same key with
1040 	 * every station but there's no such requirement; VLANs could be
1041 	 * possible.
1042 	 */
1043 
1044 	/*
1045 	 * No point in finding a key and decrypting if the frame is neither
1046 	 * addressed to us nor a multicast frame.
1047 	 */
1048 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1049 		return RX_CONTINUE;
1050 
1051 	/* start without a key */
1052 	rx->key = NULL;
1053 
1054 	if (rx->sta)
1055 		sta_ptk = rcu_dereference(rx->sta->ptk);
1056 
1057 	fc = hdr->frame_control;
1058 
1059 	if (!ieee80211_has_protected(fc))
1060 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1061 
1062 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1063 		rx->key = sta_ptk;
1064 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1065 		    (status->flag & RX_FLAG_IV_STRIPPED))
1066 			return RX_CONTINUE;
1067 		/* Skip decryption if the frame is not protected. */
1068 		if (!ieee80211_has_protected(fc))
1069 			return RX_CONTINUE;
1070 	} else if (mmie_keyidx >= 0) {
1071 		/* Broadcast/multicast robust management frame / BIP */
1072 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1073 		    (status->flag & RX_FLAG_IV_STRIPPED))
1074 			return RX_CONTINUE;
1075 
1076 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1077 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1078 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1079 		if (rx->sta)
1080 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1081 		if (!rx->key)
1082 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1083 	} else if (!ieee80211_has_protected(fc)) {
1084 		/*
1085 		 * The frame was not protected, so skip decryption. However, we
1086 		 * need to set rx->key if there is a key that could have been
1087 		 * used so that the frame may be dropped if encryption would
1088 		 * have been expected.
1089 		 */
1090 		struct ieee80211_key *key = NULL;
1091 		struct ieee80211_sub_if_data *sdata = rx->sdata;
1092 		int i;
1093 
1094 		if (ieee80211_is_mgmt(fc) &&
1095 		    is_multicast_ether_addr(hdr->addr1) &&
1096 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1097 			rx->key = key;
1098 		else {
1099 			if (rx->sta) {
1100 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1101 					key = rcu_dereference(rx->sta->gtk[i]);
1102 					if (key)
1103 						break;
1104 				}
1105 			}
1106 			if (!key) {
1107 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1108 					key = rcu_dereference(sdata->keys[i]);
1109 					if (key)
1110 						break;
1111 				}
1112 			}
1113 			if (key)
1114 				rx->key = key;
1115 		}
1116 		return RX_CONTINUE;
1117 	} else {
1118 		u8 keyid;
1119 		/*
1120 		 * The device doesn't give us the IV so we won't be
1121 		 * able to look up the key. That's ok though, we
1122 		 * don't need to decrypt the frame, we just won't
1123 		 * be able to keep statistics accurate.
1124 		 * Except for key threshold notifications, should
1125 		 * we somehow allow the driver to tell us which key
1126 		 * the hardware used if this flag is set?
1127 		 */
1128 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1129 		    (status->flag & RX_FLAG_IV_STRIPPED))
1130 			return RX_CONTINUE;
1131 
1132 		hdrlen = ieee80211_hdrlen(fc);
1133 
1134 		if (rx->skb->len < 8 + hdrlen)
1135 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1136 
1137 		/*
1138 		 * no need to call ieee80211_wep_get_keyidx,
1139 		 * it verifies a bunch of things we've done already
1140 		 */
1141 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1142 		keyidx = keyid >> 6;
1143 
1144 		/* check per-station GTK first, if multicast packet */
1145 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1146 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1147 
1148 		/* if not found, try default key */
1149 		if (!rx->key) {
1150 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1151 
1152 			/*
1153 			 * RSNA-protected unicast frames should always be
1154 			 * sent with pairwise or station-to-station keys,
1155 			 * but for WEP we allow using a key index as well.
1156 			 */
1157 			if (rx->key &&
1158 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1159 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1160 			    !is_multicast_ether_addr(hdr->addr1))
1161 				rx->key = NULL;
1162 		}
1163 	}
1164 
1165 	if (rx->key) {
1166 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1167 			return RX_DROP_MONITOR;
1168 
1169 		rx->key->tx_rx_count++;
1170 		/* TODO: add threshold stuff again */
1171 	} else {
1172 		return RX_DROP_MONITOR;
1173 	}
1174 
1175 	switch (rx->key->conf.cipher) {
1176 	case WLAN_CIPHER_SUITE_WEP40:
1177 	case WLAN_CIPHER_SUITE_WEP104:
1178 		result = ieee80211_crypto_wep_decrypt(rx);
1179 		break;
1180 	case WLAN_CIPHER_SUITE_TKIP:
1181 		result = ieee80211_crypto_tkip_decrypt(rx);
1182 		break;
1183 	case WLAN_CIPHER_SUITE_CCMP:
1184 		result = ieee80211_crypto_ccmp_decrypt(rx);
1185 		break;
1186 	case WLAN_CIPHER_SUITE_AES_CMAC:
1187 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1188 		break;
1189 	default:
1190 		/*
1191 		 * We can reach here only with HW-only algorithms
1192 		 * but why didn't it decrypt the frame?!
1193 		 */
1194 		return RX_DROP_UNUSABLE;
1195 	}
1196 
1197 	/* the hdr variable is invalid after the decrypt handlers */
1198 
1199 	/* either the frame has been decrypted or will be dropped */
1200 	status->flag |= RX_FLAG_DECRYPTED;
1201 
1202 	return result;
1203 }
1204 
1205 static ieee80211_rx_result debug_noinline
1206 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1207 {
1208 	struct ieee80211_local *local;
1209 	struct ieee80211_hdr *hdr;
1210 	struct sk_buff *skb;
1211 
1212 	local = rx->local;
1213 	skb = rx->skb;
1214 	hdr = (struct ieee80211_hdr *) skb->data;
1215 
1216 	if (!local->pspolling)
1217 		return RX_CONTINUE;
1218 
1219 	if (!ieee80211_has_fromds(hdr->frame_control))
1220 		/* this is not from AP */
1221 		return RX_CONTINUE;
1222 
1223 	if (!ieee80211_is_data(hdr->frame_control))
1224 		return RX_CONTINUE;
1225 
1226 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1227 		/* AP has no more frames buffered for us */
1228 		local->pspolling = false;
1229 		return RX_CONTINUE;
1230 	}
1231 
1232 	/* more data bit is set, let's request a new frame from the AP */
1233 	ieee80211_send_pspoll(local, rx->sdata);
1234 
1235 	return RX_CONTINUE;
1236 }
1237 
1238 static void sta_ps_start(struct sta_info *sta)
1239 {
1240 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1241 	struct ieee80211_local *local = sdata->local;
1242 	struct ps_data *ps;
1243 
1244 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1245 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1246 		ps = &sdata->bss->ps;
1247 	else
1248 		return;
1249 
1250 	atomic_inc(&ps->num_sta_ps);
1251 	set_sta_flag(sta, WLAN_STA_PS_STA);
1252 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1253 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1254 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1255 	       sta->sta.addr, sta->sta.aid);
1256 }
1257 
1258 static void sta_ps_end(struct sta_info *sta)
1259 {
1260 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1261 	       sta->sta.addr, sta->sta.aid);
1262 
1263 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1264 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1265 		       sta->sta.addr, sta->sta.aid);
1266 		return;
1267 	}
1268 
1269 	ieee80211_sta_ps_deliver_wakeup(sta);
1270 }
1271 
1272 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1273 {
1274 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1275 	bool in_ps;
1276 
1277 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1278 
1279 	/* Don't let the same PS state be set twice */
1280 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1281 	if ((start && in_ps) || (!start && !in_ps))
1282 		return -EINVAL;
1283 
1284 	if (start)
1285 		sta_ps_start(sta_inf);
1286 	else
1287 		sta_ps_end(sta_inf);
1288 
1289 	return 0;
1290 }
1291 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1292 
1293 static ieee80211_rx_result debug_noinline
1294 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1295 {
1296 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1297 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1298 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1299 	int tid, ac;
1300 
1301 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1302 		return RX_CONTINUE;
1303 
1304 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1305 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1306 		return RX_CONTINUE;
1307 
1308 	/*
1309 	 * The device handles station powersave, so don't do anything about
1310 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1311 	 * it to mac80211 since they're handled.)
1312 	 */
1313 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1314 		return RX_CONTINUE;
1315 
1316 	/*
1317 	 * Don't do anything if the station isn't already asleep. In
1318 	 * the uAPSD case, the station will probably be marked asleep,
1319 	 * in the PS-Poll case the station must be confused ...
1320 	 */
1321 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1322 		return RX_CONTINUE;
1323 
1324 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1325 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1326 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1327 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1328 			else
1329 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1330 		}
1331 
1332 		/* Free PS Poll skb here instead of returning RX_DROP that would
1333 		 * count as an dropped frame. */
1334 		dev_kfree_skb(rx->skb);
1335 
1336 		return RX_QUEUED;
1337 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1338 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1339 		   ieee80211_has_pm(hdr->frame_control) &&
1340 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1341 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1342 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1343 		ac = ieee802_1d_to_ac[tid & 7];
1344 
1345 		/*
1346 		 * If this AC is not trigger-enabled do nothing.
1347 		 *
1348 		 * NB: This could/should check a separate bitmap of trigger-
1349 		 * enabled queues, but for now we only implement uAPSD w/o
1350 		 * TSPEC changes to the ACs, so they're always the same.
1351 		 */
1352 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1353 			return RX_CONTINUE;
1354 
1355 		/* if we are in a service period, do nothing */
1356 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1357 			return RX_CONTINUE;
1358 
1359 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1360 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1361 		else
1362 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1363 	}
1364 
1365 	return RX_CONTINUE;
1366 }
1367 
1368 static ieee80211_rx_result debug_noinline
1369 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1370 {
1371 	struct sta_info *sta = rx->sta;
1372 	struct sk_buff *skb = rx->skb;
1373 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1374 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1375 
1376 	if (!sta)
1377 		return RX_CONTINUE;
1378 
1379 	/*
1380 	 * Update last_rx only for IBSS packets which are for the current
1381 	 * BSSID and for station already AUTHORIZED to avoid keeping the
1382 	 * current IBSS network alive in cases where other STAs start
1383 	 * using different BSSID. This will also give the station another
1384 	 * chance to restart the authentication/authorization in case
1385 	 * something went wrong the first time.
1386 	 */
1387 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1388 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1389 						NL80211_IFTYPE_ADHOC);
1390 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1391 		    test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1392 			sta->last_rx = jiffies;
1393 			if (ieee80211_is_data(hdr->frame_control)) {
1394 				sta->last_rx_rate_idx = status->rate_idx;
1395 				sta->last_rx_rate_flag = status->flag;
1396 				sta->last_rx_rate_vht_nss = status->vht_nss;
1397 			}
1398 		}
1399 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1400 		/*
1401 		 * Mesh beacons will update last_rx when if they are found to
1402 		 * match the current local configuration when processed.
1403 		 */
1404 		sta->last_rx = jiffies;
1405 		if (ieee80211_is_data(hdr->frame_control)) {
1406 			sta->last_rx_rate_idx = status->rate_idx;
1407 			sta->last_rx_rate_flag = status->flag;
1408 			sta->last_rx_rate_vht_nss = status->vht_nss;
1409 		}
1410 	}
1411 
1412 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1413 		return RX_CONTINUE;
1414 
1415 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1416 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1417 
1418 	sta->rx_fragments++;
1419 	sta->rx_bytes += rx->skb->len;
1420 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1421 		sta->last_signal = status->signal;
1422 		ewma_add(&sta->avg_signal, -status->signal);
1423 	}
1424 
1425 	/*
1426 	 * Change STA power saving mode only at the end of a frame
1427 	 * exchange sequence.
1428 	 */
1429 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1430 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1431 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1432 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1433 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1434 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1435 			/*
1436 			 * Ignore doze->wake transitions that are
1437 			 * indicated by non-data frames, the standard
1438 			 * is unclear here, but for example going to
1439 			 * PS mode and then scanning would cause a
1440 			 * doze->wake transition for the probe request,
1441 			 * and that is clearly undesirable.
1442 			 */
1443 			if (ieee80211_is_data(hdr->frame_control) &&
1444 			    !ieee80211_has_pm(hdr->frame_control))
1445 				sta_ps_end(sta);
1446 		} else {
1447 			if (ieee80211_has_pm(hdr->frame_control))
1448 				sta_ps_start(sta);
1449 		}
1450 	}
1451 
1452 	/* mesh power save support */
1453 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1454 		ieee80211_mps_rx_h_sta_process(sta, hdr);
1455 
1456 	/*
1457 	 * Drop (qos-)data::nullfunc frames silently, since they
1458 	 * are used only to control station power saving mode.
1459 	 */
1460 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1461 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1462 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1463 
1464 		/*
1465 		 * If we receive a 4-addr nullfunc frame from a STA
1466 		 * that was not moved to a 4-addr STA vlan yet send
1467 		 * the event to userspace and for older hostapd drop
1468 		 * the frame to the monitor interface.
1469 		 */
1470 		if (ieee80211_has_a4(hdr->frame_control) &&
1471 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1472 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1473 		      !rx->sdata->u.vlan.sta))) {
1474 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1475 				cfg80211_rx_unexpected_4addr_frame(
1476 					rx->sdata->dev, sta->sta.addr,
1477 					GFP_ATOMIC);
1478 			return RX_DROP_MONITOR;
1479 		}
1480 		/*
1481 		 * Update counter and free packet here to avoid
1482 		 * counting this as a dropped packed.
1483 		 */
1484 		sta->rx_packets++;
1485 		dev_kfree_skb(rx->skb);
1486 		return RX_QUEUED;
1487 	}
1488 
1489 	return RX_CONTINUE;
1490 } /* ieee80211_rx_h_sta_process */
1491 
1492 static inline struct ieee80211_fragment_entry *
1493 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1494 			 unsigned int frag, unsigned int seq, int rx_queue,
1495 			 struct sk_buff **skb)
1496 {
1497 	struct ieee80211_fragment_entry *entry;
1498 
1499 	entry = &sdata->fragments[sdata->fragment_next++];
1500 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1501 		sdata->fragment_next = 0;
1502 
1503 	if (!skb_queue_empty(&entry->skb_list))
1504 		__skb_queue_purge(&entry->skb_list);
1505 
1506 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1507 	*skb = NULL;
1508 	entry->first_frag_time = jiffies;
1509 	entry->seq = seq;
1510 	entry->rx_queue = rx_queue;
1511 	entry->last_frag = frag;
1512 	entry->ccmp = 0;
1513 	entry->extra_len = 0;
1514 
1515 	return entry;
1516 }
1517 
1518 static inline struct ieee80211_fragment_entry *
1519 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1520 			  unsigned int frag, unsigned int seq,
1521 			  int rx_queue, struct ieee80211_hdr *hdr)
1522 {
1523 	struct ieee80211_fragment_entry *entry;
1524 	int i, idx;
1525 
1526 	idx = sdata->fragment_next;
1527 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1528 		struct ieee80211_hdr *f_hdr;
1529 
1530 		idx--;
1531 		if (idx < 0)
1532 			idx = IEEE80211_FRAGMENT_MAX - 1;
1533 
1534 		entry = &sdata->fragments[idx];
1535 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1536 		    entry->rx_queue != rx_queue ||
1537 		    entry->last_frag + 1 != frag)
1538 			continue;
1539 
1540 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1541 
1542 		/*
1543 		 * Check ftype and addresses are equal, else check next fragment
1544 		 */
1545 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1546 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1547 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1548 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1549 			continue;
1550 
1551 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1552 			__skb_queue_purge(&entry->skb_list);
1553 			continue;
1554 		}
1555 		return entry;
1556 	}
1557 
1558 	return NULL;
1559 }
1560 
1561 static ieee80211_rx_result debug_noinline
1562 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1563 {
1564 	struct ieee80211_hdr *hdr;
1565 	u16 sc;
1566 	__le16 fc;
1567 	unsigned int frag, seq;
1568 	struct ieee80211_fragment_entry *entry;
1569 	struct sk_buff *skb;
1570 	struct ieee80211_rx_status *status;
1571 
1572 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1573 	fc = hdr->frame_control;
1574 
1575 	if (ieee80211_is_ctl(fc))
1576 		return RX_CONTINUE;
1577 
1578 	sc = le16_to_cpu(hdr->seq_ctrl);
1579 	frag = sc & IEEE80211_SCTL_FRAG;
1580 
1581 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1582 		   is_multicast_ether_addr(hdr->addr1))) {
1583 		/* not fragmented */
1584 		goto out;
1585 	}
1586 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1587 
1588 	if (skb_linearize(rx->skb))
1589 		return RX_DROP_UNUSABLE;
1590 
1591 	/*
1592 	 *  skb_linearize() might change the skb->data and
1593 	 *  previously cached variables (in this case, hdr) need to
1594 	 *  be refreshed with the new data.
1595 	 */
1596 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1597 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1598 
1599 	if (frag == 0) {
1600 		/* This is the first fragment of a new frame. */
1601 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1602 						 rx->seqno_idx, &(rx->skb));
1603 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1604 		    ieee80211_has_protected(fc)) {
1605 			int queue = rx->security_idx;
1606 			/* Store CCMP PN so that we can verify that the next
1607 			 * fragment has a sequential PN value. */
1608 			entry->ccmp = 1;
1609 			memcpy(entry->last_pn,
1610 			       rx->key->u.ccmp.rx_pn[queue],
1611 			       CCMP_PN_LEN);
1612 		}
1613 		return RX_QUEUED;
1614 	}
1615 
1616 	/* This is a fragment for a frame that should already be pending in
1617 	 * fragment cache. Add this fragment to the end of the pending entry.
1618 	 */
1619 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1620 					  rx->seqno_idx, hdr);
1621 	if (!entry) {
1622 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1623 		return RX_DROP_MONITOR;
1624 	}
1625 
1626 	/* Verify that MPDUs within one MSDU have sequential PN values.
1627 	 * (IEEE 802.11i, 8.3.3.4.5) */
1628 	if (entry->ccmp) {
1629 		int i;
1630 		u8 pn[CCMP_PN_LEN], *rpn;
1631 		int queue;
1632 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1633 			return RX_DROP_UNUSABLE;
1634 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1635 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1636 			pn[i]++;
1637 			if (pn[i])
1638 				break;
1639 		}
1640 		queue = rx->security_idx;
1641 		rpn = rx->key->u.ccmp.rx_pn[queue];
1642 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1643 			return RX_DROP_UNUSABLE;
1644 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1645 	}
1646 
1647 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1648 	__skb_queue_tail(&entry->skb_list, rx->skb);
1649 	entry->last_frag = frag;
1650 	entry->extra_len += rx->skb->len;
1651 	if (ieee80211_has_morefrags(fc)) {
1652 		rx->skb = NULL;
1653 		return RX_QUEUED;
1654 	}
1655 
1656 	rx->skb = __skb_dequeue(&entry->skb_list);
1657 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1658 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1659 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1660 					      GFP_ATOMIC))) {
1661 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1662 			__skb_queue_purge(&entry->skb_list);
1663 			return RX_DROP_UNUSABLE;
1664 		}
1665 	}
1666 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1667 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1668 		dev_kfree_skb(skb);
1669 	}
1670 
1671 	/* Complete frame has been reassembled - process it now */
1672 	status = IEEE80211_SKB_RXCB(rx->skb);
1673 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1674 
1675  out:
1676 	if (rx->sta)
1677 		rx->sta->rx_packets++;
1678 	if (is_multicast_ether_addr(hdr->addr1))
1679 		rx->local->dot11MulticastReceivedFrameCount++;
1680 	else
1681 		ieee80211_led_rx(rx->local);
1682 	return RX_CONTINUE;
1683 }
1684 
1685 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1686 {
1687 	if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1688 		return -EACCES;
1689 
1690 	return 0;
1691 }
1692 
1693 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1694 {
1695 	struct sk_buff *skb = rx->skb;
1696 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1697 
1698 	/*
1699 	 * Pass through unencrypted frames if the hardware has
1700 	 * decrypted them already.
1701 	 */
1702 	if (status->flag & RX_FLAG_DECRYPTED)
1703 		return 0;
1704 
1705 	/* Drop unencrypted frames if key is set. */
1706 	if (unlikely(!ieee80211_has_protected(fc) &&
1707 		     !ieee80211_is_nullfunc(fc) &&
1708 		     ieee80211_is_data(fc) &&
1709 		     (rx->key || rx->sdata->drop_unencrypted)))
1710 		return -EACCES;
1711 
1712 	return 0;
1713 }
1714 
1715 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1716 {
1717 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1718 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1719 	__le16 fc = hdr->frame_control;
1720 
1721 	/*
1722 	 * Pass through unencrypted frames if the hardware has
1723 	 * decrypted them already.
1724 	 */
1725 	if (status->flag & RX_FLAG_DECRYPTED)
1726 		return 0;
1727 
1728 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1729 		if (unlikely(!ieee80211_has_protected(fc) &&
1730 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1731 			     rx->key)) {
1732 			if (ieee80211_is_deauth(fc))
1733 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1734 							    rx->skb->data,
1735 							    rx->skb->len);
1736 			else if (ieee80211_is_disassoc(fc))
1737 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1738 							      rx->skb->data,
1739 							      rx->skb->len);
1740 			return -EACCES;
1741 		}
1742 		/* BIP does not use Protected field, so need to check MMIE */
1743 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1744 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1745 			if (ieee80211_is_deauth(fc))
1746 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1747 							    rx->skb->data,
1748 							    rx->skb->len);
1749 			else if (ieee80211_is_disassoc(fc))
1750 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1751 							      rx->skb->data,
1752 							      rx->skb->len);
1753 			return -EACCES;
1754 		}
1755 		/*
1756 		 * When using MFP, Action frames are not allowed prior to
1757 		 * having configured keys.
1758 		 */
1759 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1760 			     ieee80211_is_robust_mgmt_frame(
1761 				     (struct ieee80211_hdr *) rx->skb->data)))
1762 			return -EACCES;
1763 	}
1764 
1765 	return 0;
1766 }
1767 
1768 static int
1769 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1770 {
1771 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1772 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1773 	bool check_port_control = false;
1774 	struct ethhdr *ehdr;
1775 	int ret;
1776 
1777 	*port_control = false;
1778 	if (ieee80211_has_a4(hdr->frame_control) &&
1779 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1780 		return -1;
1781 
1782 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1783 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1784 
1785 		if (!sdata->u.mgd.use_4addr)
1786 			return -1;
1787 		else
1788 			check_port_control = true;
1789 	}
1790 
1791 	if (is_multicast_ether_addr(hdr->addr1) &&
1792 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1793 		return -1;
1794 
1795 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1796 	if (ret < 0)
1797 		return ret;
1798 
1799 	ehdr = (struct ethhdr *) rx->skb->data;
1800 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1801 		*port_control = true;
1802 	else if (check_port_control)
1803 		return -1;
1804 
1805 	return 0;
1806 }
1807 
1808 /*
1809  * requires that rx->skb is a frame with ethernet header
1810  */
1811 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1812 {
1813 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1814 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1815 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1816 
1817 	/*
1818 	 * Allow EAPOL frames to us/the PAE group address regardless
1819 	 * of whether the frame was encrypted or not.
1820 	 */
1821 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1822 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1823 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1824 		return true;
1825 
1826 	if (ieee80211_802_1x_port_control(rx) ||
1827 	    ieee80211_drop_unencrypted(rx, fc))
1828 		return false;
1829 
1830 	return true;
1831 }
1832 
1833 /*
1834  * requires that rx->skb is a frame with ethernet header
1835  */
1836 static void
1837 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1838 {
1839 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1840 	struct net_device *dev = sdata->dev;
1841 	struct sk_buff *skb, *xmit_skb;
1842 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1843 	struct sta_info *dsta;
1844 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1845 
1846 	skb = rx->skb;
1847 	xmit_skb = NULL;
1848 
1849 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1850 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1851 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1852 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1853 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1854 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1855 			/*
1856 			 * send multicast frames both to higher layers in
1857 			 * local net stack and back to the wireless medium
1858 			 */
1859 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1860 			if (!xmit_skb)
1861 				net_info_ratelimited("%s: failed to clone multicast frame\n",
1862 						    dev->name);
1863 		} else {
1864 			dsta = sta_info_get(sdata, skb->data);
1865 			if (dsta) {
1866 				/*
1867 				 * The destination station is associated to
1868 				 * this AP (in this VLAN), so send the frame
1869 				 * directly to it and do not pass it to local
1870 				 * net stack.
1871 				 */
1872 				xmit_skb = skb;
1873 				skb = NULL;
1874 			}
1875 		}
1876 	}
1877 
1878 	if (skb) {
1879 		int align __maybe_unused;
1880 
1881 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1882 		/*
1883 		 * 'align' will only take the values 0 or 2 here
1884 		 * since all frames are required to be aligned
1885 		 * to 2-byte boundaries when being passed to
1886 		 * mac80211; the code here works just as well if
1887 		 * that isn't true, but mac80211 assumes it can
1888 		 * access fields as 2-byte aligned (e.g. for
1889 		 * compare_ether_addr)
1890 		 */
1891 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1892 		if (align) {
1893 			if (WARN_ON(skb_headroom(skb) < 3)) {
1894 				dev_kfree_skb(skb);
1895 				skb = NULL;
1896 			} else {
1897 				u8 *data = skb->data;
1898 				size_t len = skb_headlen(skb);
1899 				skb->data -= align;
1900 				memmove(skb->data, data, len);
1901 				skb_set_tail_pointer(skb, len);
1902 			}
1903 		}
1904 #endif
1905 
1906 		if (skb) {
1907 			/* deliver to local stack */
1908 			skb->protocol = eth_type_trans(skb, dev);
1909 			memset(skb->cb, 0, sizeof(skb->cb));
1910 			netif_receive_skb(skb);
1911 		}
1912 	}
1913 
1914 	if (xmit_skb) {
1915 		/*
1916 		 * Send to wireless media and increase priority by 256 to
1917 		 * keep the received priority instead of reclassifying
1918 		 * the frame (see cfg80211_classify8021d).
1919 		 */
1920 		xmit_skb->priority += 256;
1921 		xmit_skb->protocol = htons(ETH_P_802_3);
1922 		skb_reset_network_header(xmit_skb);
1923 		skb_reset_mac_header(xmit_skb);
1924 		dev_queue_xmit(xmit_skb);
1925 	}
1926 }
1927 
1928 static ieee80211_rx_result debug_noinline
1929 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1930 {
1931 	struct net_device *dev = rx->sdata->dev;
1932 	struct sk_buff *skb = rx->skb;
1933 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1934 	__le16 fc = hdr->frame_control;
1935 	struct sk_buff_head frame_list;
1936 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1937 
1938 	if (unlikely(!ieee80211_is_data(fc)))
1939 		return RX_CONTINUE;
1940 
1941 	if (unlikely(!ieee80211_is_data_present(fc)))
1942 		return RX_DROP_MONITOR;
1943 
1944 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1945 		return RX_CONTINUE;
1946 
1947 	if (ieee80211_has_a4(hdr->frame_control) &&
1948 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1949 	    !rx->sdata->u.vlan.sta)
1950 		return RX_DROP_UNUSABLE;
1951 
1952 	if (is_multicast_ether_addr(hdr->addr1) &&
1953 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1954 	      rx->sdata->u.vlan.sta) ||
1955 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1956 	      rx->sdata->u.mgd.use_4addr)))
1957 		return RX_DROP_UNUSABLE;
1958 
1959 	skb->dev = dev;
1960 	__skb_queue_head_init(&frame_list);
1961 
1962 	if (skb_linearize(skb))
1963 		return RX_DROP_UNUSABLE;
1964 
1965 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1966 				 rx->sdata->vif.type,
1967 				 rx->local->hw.extra_tx_headroom, true);
1968 
1969 	while (!skb_queue_empty(&frame_list)) {
1970 		rx->skb = __skb_dequeue(&frame_list);
1971 
1972 		if (!ieee80211_frame_allowed(rx, fc)) {
1973 			dev_kfree_skb(rx->skb);
1974 			continue;
1975 		}
1976 		dev->stats.rx_packets++;
1977 		dev->stats.rx_bytes += rx->skb->len;
1978 
1979 		ieee80211_deliver_skb(rx);
1980 	}
1981 
1982 	return RX_QUEUED;
1983 }
1984 
1985 #ifdef CONFIG_MAC80211_MESH
1986 static ieee80211_rx_result
1987 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1988 {
1989 	struct ieee80211_hdr *fwd_hdr, *hdr;
1990 	struct ieee80211_tx_info *info;
1991 	struct ieee80211s_hdr *mesh_hdr;
1992 	struct sk_buff *skb = rx->skb, *fwd_skb;
1993 	struct ieee80211_local *local = rx->local;
1994 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1995 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1996 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1997 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1998 	u16 q, hdrlen;
1999 
2000 	hdr = (struct ieee80211_hdr *) skb->data;
2001 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
2002 
2003 	/* make sure fixed part of mesh header is there, also checks skb len */
2004 	if (!pskb_may_pull(rx->skb, hdrlen + 6))
2005 		return RX_DROP_MONITOR;
2006 
2007 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2008 
2009 	/* make sure full mesh header is there, also checks skb len */
2010 	if (!pskb_may_pull(rx->skb,
2011 			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2012 		return RX_DROP_MONITOR;
2013 
2014 	/* reload pointers */
2015 	hdr = (struct ieee80211_hdr *) skb->data;
2016 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2017 
2018 	/* frame is in RMC, don't forward */
2019 	if (ieee80211_is_data(hdr->frame_control) &&
2020 	    is_multicast_ether_addr(hdr->addr1) &&
2021 	    mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2022 		return RX_DROP_MONITOR;
2023 
2024 	if (!ieee80211_is_data(hdr->frame_control) ||
2025 	    !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2026 		return RX_CONTINUE;
2027 
2028 	if (!mesh_hdr->ttl)
2029 		return RX_DROP_MONITOR;
2030 
2031 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
2032 		struct mesh_path *mppath;
2033 		char *proxied_addr;
2034 		char *mpp_addr;
2035 
2036 		if (is_multicast_ether_addr(hdr->addr1)) {
2037 			mpp_addr = hdr->addr3;
2038 			proxied_addr = mesh_hdr->eaddr1;
2039 		} else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2040 			/* has_a4 already checked in ieee80211_rx_mesh_check */
2041 			mpp_addr = hdr->addr4;
2042 			proxied_addr = mesh_hdr->eaddr2;
2043 		} else {
2044 			return RX_DROP_MONITOR;
2045 		}
2046 
2047 		rcu_read_lock();
2048 		mppath = mpp_path_lookup(sdata, proxied_addr);
2049 		if (!mppath) {
2050 			mpp_path_add(sdata, proxied_addr, mpp_addr);
2051 		} else {
2052 			spin_lock_bh(&mppath->state_lock);
2053 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
2054 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2055 			spin_unlock_bh(&mppath->state_lock);
2056 		}
2057 		rcu_read_unlock();
2058 	}
2059 
2060 	/* Frame has reached destination.  Don't forward */
2061 	if (!is_multicast_ether_addr(hdr->addr1) &&
2062 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
2063 		return RX_CONTINUE;
2064 
2065 	q = ieee80211_select_queue_80211(sdata, skb, hdr);
2066 	if (ieee80211_queue_stopped(&local->hw, q)) {
2067 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2068 		return RX_DROP_MONITOR;
2069 	}
2070 	skb_set_queue_mapping(skb, q);
2071 
2072 	if (!--mesh_hdr->ttl) {
2073 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2074 		goto out;
2075 	}
2076 
2077 	if (!ifmsh->mshcfg.dot11MeshForwarding)
2078 		goto out;
2079 
2080 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
2081 	if (!fwd_skb) {
2082 		net_info_ratelimited("%s: failed to clone mesh frame\n",
2083 				    sdata->name);
2084 		goto out;
2085 	}
2086 
2087 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2088 	fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2089 	info = IEEE80211_SKB_CB(fwd_skb);
2090 	memset(info, 0, sizeof(*info));
2091 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2092 	info->control.vif = &rx->sdata->vif;
2093 	info->control.jiffies = jiffies;
2094 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2095 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2096 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2097 		/* update power mode indication when forwarding */
2098 		ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2099 	} else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2100 		/* mesh power mode flags updated in mesh_nexthop_lookup */
2101 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2102 	} else {
2103 		/* unable to resolve next hop */
2104 		mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2105 				   fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2106 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2107 		kfree_skb(fwd_skb);
2108 		return RX_DROP_MONITOR;
2109 	}
2110 
2111 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2112 	ieee80211_add_pending_skb(local, fwd_skb);
2113  out:
2114 	if (is_multicast_ether_addr(hdr->addr1) ||
2115 	    sdata->dev->flags & IFF_PROMISC)
2116 		return RX_CONTINUE;
2117 	else
2118 		return RX_DROP_MONITOR;
2119 }
2120 #endif
2121 
2122 static ieee80211_rx_result debug_noinline
2123 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2124 {
2125 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2126 	struct ieee80211_local *local = rx->local;
2127 	struct net_device *dev = sdata->dev;
2128 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2129 	__le16 fc = hdr->frame_control;
2130 	bool port_control;
2131 	int err;
2132 
2133 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2134 		return RX_CONTINUE;
2135 
2136 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2137 		return RX_DROP_MONITOR;
2138 
2139 	/*
2140 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2141 	 * also drop the frame to cooked monitor interfaces.
2142 	 */
2143 	if (ieee80211_has_a4(hdr->frame_control) &&
2144 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2145 		if (rx->sta &&
2146 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2147 			cfg80211_rx_unexpected_4addr_frame(
2148 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2149 		return RX_DROP_MONITOR;
2150 	}
2151 
2152 	err = __ieee80211_data_to_8023(rx, &port_control);
2153 	if (unlikely(err))
2154 		return RX_DROP_UNUSABLE;
2155 
2156 	if (!ieee80211_frame_allowed(rx, fc))
2157 		return RX_DROP_MONITOR;
2158 
2159 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2160 	    unlikely(port_control) && sdata->bss) {
2161 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2162 				     u.ap);
2163 		dev = sdata->dev;
2164 		rx->sdata = sdata;
2165 	}
2166 
2167 	rx->skb->dev = dev;
2168 
2169 	dev->stats.rx_packets++;
2170 	dev->stats.rx_bytes += rx->skb->len;
2171 
2172 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2173 	    !is_multicast_ether_addr(
2174 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2175 	    (!local->scanning &&
2176 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2177 			mod_timer(&local->dynamic_ps_timer, jiffies +
2178 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2179 	}
2180 
2181 	ieee80211_deliver_skb(rx);
2182 
2183 	return RX_QUEUED;
2184 }
2185 
2186 static ieee80211_rx_result debug_noinline
2187 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2188 {
2189 	struct sk_buff *skb = rx->skb;
2190 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2191 	struct tid_ampdu_rx *tid_agg_rx;
2192 	u16 start_seq_num;
2193 	u16 tid;
2194 
2195 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2196 		return RX_CONTINUE;
2197 
2198 	if (ieee80211_is_back_req(bar->frame_control)) {
2199 		struct {
2200 			__le16 control, start_seq_num;
2201 		} __packed bar_data;
2202 
2203 		if (!rx->sta)
2204 			return RX_DROP_MONITOR;
2205 
2206 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2207 				  &bar_data, sizeof(bar_data)))
2208 			return RX_DROP_MONITOR;
2209 
2210 		tid = le16_to_cpu(bar_data.control) >> 12;
2211 
2212 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2213 		if (!tid_agg_rx)
2214 			return RX_DROP_MONITOR;
2215 
2216 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2217 
2218 		/* reset session timer */
2219 		if (tid_agg_rx->timeout)
2220 			mod_timer(&tid_agg_rx->session_timer,
2221 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2222 
2223 		spin_lock(&tid_agg_rx->reorder_lock);
2224 		/* release stored frames up to start of BAR */
2225 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2226 						 start_seq_num, frames);
2227 		spin_unlock(&tid_agg_rx->reorder_lock);
2228 
2229 		kfree_skb(skb);
2230 		return RX_QUEUED;
2231 	}
2232 
2233 	/*
2234 	 * After this point, we only want management frames,
2235 	 * so we can drop all remaining control frames to
2236 	 * cooked monitor interfaces.
2237 	 */
2238 	return RX_DROP_MONITOR;
2239 }
2240 
2241 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2242 					   struct ieee80211_mgmt *mgmt,
2243 					   size_t len)
2244 {
2245 	struct ieee80211_local *local = sdata->local;
2246 	struct sk_buff *skb;
2247 	struct ieee80211_mgmt *resp;
2248 
2249 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2250 		/* Not to own unicast address */
2251 		return;
2252 	}
2253 
2254 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2255 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2256 		/* Not from the current AP or not associated yet. */
2257 		return;
2258 	}
2259 
2260 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2261 		/* Too short SA Query request frame */
2262 		return;
2263 	}
2264 
2265 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2266 	if (skb == NULL)
2267 		return;
2268 
2269 	skb_reserve(skb, local->hw.extra_tx_headroom);
2270 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2271 	memset(resp, 0, 24);
2272 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2273 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2274 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2275 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2276 					  IEEE80211_STYPE_ACTION);
2277 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2278 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2279 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2280 	memcpy(resp->u.action.u.sa_query.trans_id,
2281 	       mgmt->u.action.u.sa_query.trans_id,
2282 	       WLAN_SA_QUERY_TR_ID_LEN);
2283 
2284 	ieee80211_tx_skb(sdata, skb);
2285 }
2286 
2287 static ieee80211_rx_result debug_noinline
2288 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2289 {
2290 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2291 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2292 
2293 	/*
2294 	 * From here on, look only at management frames.
2295 	 * Data and control frames are already handled,
2296 	 * and unknown (reserved) frames are useless.
2297 	 */
2298 	if (rx->skb->len < 24)
2299 		return RX_DROP_MONITOR;
2300 
2301 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2302 		return RX_DROP_MONITOR;
2303 
2304 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2305 	    ieee80211_is_beacon(mgmt->frame_control) &&
2306 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2307 		int sig = 0;
2308 
2309 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2310 			sig = status->signal;
2311 
2312 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2313 					    rx->skb->data, rx->skb->len,
2314 					    status->freq, sig);
2315 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2316 	}
2317 
2318 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2319 		return RX_DROP_MONITOR;
2320 
2321 	if (ieee80211_drop_unencrypted_mgmt(rx))
2322 		return RX_DROP_UNUSABLE;
2323 
2324 	return RX_CONTINUE;
2325 }
2326 
2327 static ieee80211_rx_result debug_noinline
2328 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2329 {
2330 	struct ieee80211_local *local = rx->local;
2331 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2332 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2333 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2334 	int len = rx->skb->len;
2335 
2336 	if (!ieee80211_is_action(mgmt->frame_control))
2337 		return RX_CONTINUE;
2338 
2339 	/* drop too small frames */
2340 	if (len < IEEE80211_MIN_ACTION_SIZE)
2341 		return RX_DROP_UNUSABLE;
2342 
2343 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2344 	    mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2345 		return RX_DROP_UNUSABLE;
2346 
2347 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2348 		return RX_DROP_UNUSABLE;
2349 
2350 	switch (mgmt->u.action.category) {
2351 	case WLAN_CATEGORY_HT:
2352 		/* reject HT action frames from stations not supporting HT */
2353 		if (!rx->sta->sta.ht_cap.ht_supported)
2354 			goto invalid;
2355 
2356 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2357 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2358 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2359 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2360 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2361 			break;
2362 
2363 		/* verify action & smps_control/chanwidth are present */
2364 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2365 			goto invalid;
2366 
2367 		switch (mgmt->u.action.u.ht_smps.action) {
2368 		case WLAN_HT_ACTION_SMPS: {
2369 			struct ieee80211_supported_band *sband;
2370 			enum ieee80211_smps_mode smps_mode;
2371 
2372 			/* convert to HT capability */
2373 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2374 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2375 				smps_mode = IEEE80211_SMPS_OFF;
2376 				break;
2377 			case WLAN_HT_SMPS_CONTROL_STATIC:
2378 				smps_mode = IEEE80211_SMPS_STATIC;
2379 				break;
2380 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2381 				smps_mode = IEEE80211_SMPS_DYNAMIC;
2382 				break;
2383 			default:
2384 				goto invalid;
2385 			}
2386 
2387 			/* if no change do nothing */
2388 			if (rx->sta->sta.smps_mode == smps_mode)
2389 				goto handled;
2390 			rx->sta->sta.smps_mode = smps_mode;
2391 
2392 			sband = rx->local->hw.wiphy->bands[status->band];
2393 
2394 			rate_control_rate_update(local, sband, rx->sta,
2395 						 IEEE80211_RC_SMPS_CHANGED);
2396 			goto handled;
2397 		}
2398 		case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2399 			struct ieee80211_supported_band *sband;
2400 			u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2401 			enum ieee80211_sta_rx_bandwidth new_bw;
2402 
2403 			/* If it doesn't support 40 MHz it can't change ... */
2404 			if (!(rx->sta->sta.ht_cap.cap &
2405 					IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2406 				goto handled;
2407 
2408 			if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2409 				new_bw = IEEE80211_STA_RX_BW_20;
2410 			else
2411 				new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2412 
2413 			if (rx->sta->sta.bandwidth == new_bw)
2414 				goto handled;
2415 
2416 			sband = rx->local->hw.wiphy->bands[status->band];
2417 
2418 			rate_control_rate_update(local, sband, rx->sta,
2419 						 IEEE80211_RC_BW_CHANGED);
2420 			goto handled;
2421 		}
2422 		default:
2423 			goto invalid;
2424 		}
2425 
2426 		break;
2427 	case WLAN_CATEGORY_PUBLIC:
2428 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2429 			goto invalid;
2430 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2431 			break;
2432 		if (!rx->sta)
2433 			break;
2434 		if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2435 			break;
2436 		if (mgmt->u.action.u.ext_chan_switch.action_code !=
2437 				WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2438 			break;
2439 		if (len < offsetof(struct ieee80211_mgmt,
2440 				   u.action.u.ext_chan_switch.variable))
2441 			goto invalid;
2442 		goto queue;
2443 	case WLAN_CATEGORY_VHT:
2444 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2445 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2446 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2447 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2448 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2449 			break;
2450 
2451 		/* verify action code is present */
2452 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2453 			goto invalid;
2454 
2455 		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2456 		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2457 			u8 opmode;
2458 
2459 			/* verify opmode is present */
2460 			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2461 				goto invalid;
2462 
2463 			opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2464 
2465 			ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2466 						    opmode, status->band,
2467 						    false);
2468 			goto handled;
2469 		}
2470 		default:
2471 			break;
2472 		}
2473 		break;
2474 	case WLAN_CATEGORY_BACK:
2475 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2476 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2477 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2478 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2479 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2480 			break;
2481 
2482 		/* verify action_code is present */
2483 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2484 			break;
2485 
2486 		switch (mgmt->u.action.u.addba_req.action_code) {
2487 		case WLAN_ACTION_ADDBA_REQ:
2488 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2489 				   sizeof(mgmt->u.action.u.addba_req)))
2490 				goto invalid;
2491 			break;
2492 		case WLAN_ACTION_ADDBA_RESP:
2493 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2494 				   sizeof(mgmt->u.action.u.addba_resp)))
2495 				goto invalid;
2496 			break;
2497 		case WLAN_ACTION_DELBA:
2498 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2499 				   sizeof(mgmt->u.action.u.delba)))
2500 				goto invalid;
2501 			break;
2502 		default:
2503 			goto invalid;
2504 		}
2505 
2506 		goto queue;
2507 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2508 		if (status->band != IEEE80211_BAND_5GHZ)
2509 			break;
2510 
2511 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2512 			break;
2513 
2514 		/* verify action_code is present */
2515 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2516 			break;
2517 
2518 		switch (mgmt->u.action.u.measurement.action_code) {
2519 		case WLAN_ACTION_SPCT_MSR_REQ:
2520 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2521 				   sizeof(mgmt->u.action.u.measurement)))
2522 				break;
2523 			ieee80211_process_measurement_req(sdata, mgmt, len);
2524 			goto handled;
2525 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2526 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2527 				break;
2528 
2529 			if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2530 				break;
2531 
2532 			goto queue;
2533 		}
2534 		break;
2535 	case WLAN_CATEGORY_SA_QUERY:
2536 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2537 			   sizeof(mgmt->u.action.u.sa_query)))
2538 			break;
2539 
2540 		switch (mgmt->u.action.u.sa_query.action) {
2541 		case WLAN_ACTION_SA_QUERY_REQUEST:
2542 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2543 				break;
2544 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2545 			goto handled;
2546 		}
2547 		break;
2548 	case WLAN_CATEGORY_SELF_PROTECTED:
2549 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2550 			   sizeof(mgmt->u.action.u.self_prot.action_code)))
2551 			break;
2552 
2553 		switch (mgmt->u.action.u.self_prot.action_code) {
2554 		case WLAN_SP_MESH_PEERING_OPEN:
2555 		case WLAN_SP_MESH_PEERING_CLOSE:
2556 		case WLAN_SP_MESH_PEERING_CONFIRM:
2557 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2558 				goto invalid;
2559 			if (sdata->u.mesh.user_mpm)
2560 				/* userspace handles this frame */
2561 				break;
2562 			goto queue;
2563 		case WLAN_SP_MGK_INFORM:
2564 		case WLAN_SP_MGK_ACK:
2565 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2566 				goto invalid;
2567 			break;
2568 		}
2569 		break;
2570 	case WLAN_CATEGORY_MESH_ACTION:
2571 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2572 			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
2573 			break;
2574 
2575 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2576 			break;
2577 		if (mesh_action_is_path_sel(mgmt) &&
2578 		    !mesh_path_sel_is_hwmp(sdata))
2579 			break;
2580 		goto queue;
2581 	}
2582 
2583 	return RX_CONTINUE;
2584 
2585  invalid:
2586 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2587 	/* will return in the next handlers */
2588 	return RX_CONTINUE;
2589 
2590  handled:
2591 	if (rx->sta)
2592 		rx->sta->rx_packets++;
2593 	dev_kfree_skb(rx->skb);
2594 	return RX_QUEUED;
2595 
2596  queue:
2597 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2598 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2599 	ieee80211_queue_work(&local->hw, &sdata->work);
2600 	if (rx->sta)
2601 		rx->sta->rx_packets++;
2602 	return RX_QUEUED;
2603 }
2604 
2605 static ieee80211_rx_result debug_noinline
2606 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2607 {
2608 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2609 	int sig = 0;
2610 
2611 	/* skip known-bad action frames and return them in the next handler */
2612 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2613 		return RX_CONTINUE;
2614 
2615 	/*
2616 	 * Getting here means the kernel doesn't know how to handle
2617 	 * it, but maybe userspace does ... include returned frames
2618 	 * so userspace can register for those to know whether ones
2619 	 * it transmitted were processed or returned.
2620 	 */
2621 
2622 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2623 		sig = status->signal;
2624 
2625 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2626 			     rx->skb->data, rx->skb->len,
2627 			     GFP_ATOMIC)) {
2628 		if (rx->sta)
2629 			rx->sta->rx_packets++;
2630 		dev_kfree_skb(rx->skb);
2631 		return RX_QUEUED;
2632 	}
2633 
2634 	return RX_CONTINUE;
2635 }
2636 
2637 static ieee80211_rx_result debug_noinline
2638 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2639 {
2640 	struct ieee80211_local *local = rx->local;
2641 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2642 	struct sk_buff *nskb;
2643 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2644 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2645 
2646 	if (!ieee80211_is_action(mgmt->frame_control))
2647 		return RX_CONTINUE;
2648 
2649 	/*
2650 	 * For AP mode, hostapd is responsible for handling any action
2651 	 * frames that we didn't handle, including returning unknown
2652 	 * ones. For all other modes we will return them to the sender,
2653 	 * setting the 0x80 bit in the action category, as required by
2654 	 * 802.11-2012 9.24.4.
2655 	 * Newer versions of hostapd shall also use the management frame
2656 	 * registration mechanisms, but older ones still use cooked
2657 	 * monitor interfaces so push all frames there.
2658 	 */
2659 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2660 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2661 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2662 		return RX_DROP_MONITOR;
2663 
2664 	if (is_multicast_ether_addr(mgmt->da))
2665 		return RX_DROP_MONITOR;
2666 
2667 	/* do not return rejected action frames */
2668 	if (mgmt->u.action.category & 0x80)
2669 		return RX_DROP_UNUSABLE;
2670 
2671 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2672 			       GFP_ATOMIC);
2673 	if (nskb) {
2674 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2675 
2676 		nmgmt->u.action.category |= 0x80;
2677 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2678 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2679 
2680 		memset(nskb->cb, 0, sizeof(nskb->cb));
2681 
2682 		if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2683 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2684 
2685 			info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2686 				      IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2687 				      IEEE80211_TX_CTL_NO_CCK_RATE;
2688 			if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2689 				info->hw_queue =
2690 					local->hw.offchannel_tx_hw_queue;
2691 		}
2692 
2693 		__ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2694 					    status->band);
2695 	}
2696 	dev_kfree_skb(rx->skb);
2697 	return RX_QUEUED;
2698 }
2699 
2700 static ieee80211_rx_result debug_noinline
2701 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2702 {
2703 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2704 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2705 	__le16 stype;
2706 
2707 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2708 
2709 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2710 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2711 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2712 		return RX_DROP_MONITOR;
2713 
2714 	switch (stype) {
2715 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2716 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2717 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2718 		/* process for all: mesh, mlme, ibss */
2719 		break;
2720 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2721 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2722 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2723 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2724 		if (is_multicast_ether_addr(mgmt->da) &&
2725 		    !is_broadcast_ether_addr(mgmt->da))
2726 			return RX_DROP_MONITOR;
2727 
2728 		/* process only for station */
2729 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2730 			return RX_DROP_MONITOR;
2731 		break;
2732 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2733 		/* process only for ibss and mesh */
2734 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2735 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2736 			return RX_DROP_MONITOR;
2737 		break;
2738 	default:
2739 		return RX_DROP_MONITOR;
2740 	}
2741 
2742 	/* queue up frame and kick off work to process it */
2743 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2744 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2745 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2746 	if (rx->sta)
2747 		rx->sta->rx_packets++;
2748 
2749 	return RX_QUEUED;
2750 }
2751 
2752 /* TODO: use IEEE80211_RX_FRAGMENTED */
2753 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2754 					struct ieee80211_rate *rate)
2755 {
2756 	struct ieee80211_sub_if_data *sdata;
2757 	struct ieee80211_local *local = rx->local;
2758 	struct sk_buff *skb = rx->skb, *skb2;
2759 	struct net_device *prev_dev = NULL;
2760 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2761 	int needed_headroom;
2762 
2763 	/*
2764 	 * If cooked monitor has been processed already, then
2765 	 * don't do it again. If not, set the flag.
2766 	 */
2767 	if (rx->flags & IEEE80211_RX_CMNTR)
2768 		goto out_free_skb;
2769 	rx->flags |= IEEE80211_RX_CMNTR;
2770 
2771 	/* If there are no cooked monitor interfaces, just free the SKB */
2772 	if (!local->cooked_mntrs)
2773 		goto out_free_skb;
2774 
2775 	/* room for the radiotap header based on driver features */
2776 	needed_headroom = ieee80211_rx_radiotap_space(local, status);
2777 
2778 	if (skb_headroom(skb) < needed_headroom &&
2779 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2780 		goto out_free_skb;
2781 
2782 	/* prepend radiotap information */
2783 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2784 					 false);
2785 
2786 	skb_set_mac_header(skb, 0);
2787 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2788 	skb->pkt_type = PACKET_OTHERHOST;
2789 	skb->protocol = htons(ETH_P_802_2);
2790 
2791 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2792 		if (!ieee80211_sdata_running(sdata))
2793 			continue;
2794 
2795 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2796 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2797 			continue;
2798 
2799 		if (prev_dev) {
2800 			skb2 = skb_clone(skb, GFP_ATOMIC);
2801 			if (skb2) {
2802 				skb2->dev = prev_dev;
2803 				netif_receive_skb(skb2);
2804 			}
2805 		}
2806 
2807 		prev_dev = sdata->dev;
2808 		sdata->dev->stats.rx_packets++;
2809 		sdata->dev->stats.rx_bytes += skb->len;
2810 	}
2811 
2812 	if (prev_dev) {
2813 		skb->dev = prev_dev;
2814 		netif_receive_skb(skb);
2815 		return;
2816 	}
2817 
2818  out_free_skb:
2819 	dev_kfree_skb(skb);
2820 }
2821 
2822 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2823 					 ieee80211_rx_result res)
2824 {
2825 	switch (res) {
2826 	case RX_DROP_MONITOR:
2827 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2828 		if (rx->sta)
2829 			rx->sta->rx_dropped++;
2830 		/* fall through */
2831 	case RX_CONTINUE: {
2832 		struct ieee80211_rate *rate = NULL;
2833 		struct ieee80211_supported_band *sband;
2834 		struct ieee80211_rx_status *status;
2835 
2836 		status = IEEE80211_SKB_RXCB((rx->skb));
2837 
2838 		sband = rx->local->hw.wiphy->bands[status->band];
2839 		if (!(status->flag & RX_FLAG_HT) &&
2840 		    !(status->flag & RX_FLAG_VHT))
2841 			rate = &sband->bitrates[status->rate_idx];
2842 
2843 		ieee80211_rx_cooked_monitor(rx, rate);
2844 		break;
2845 		}
2846 	case RX_DROP_UNUSABLE:
2847 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2848 		if (rx->sta)
2849 			rx->sta->rx_dropped++;
2850 		dev_kfree_skb(rx->skb);
2851 		break;
2852 	case RX_QUEUED:
2853 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2854 		break;
2855 	}
2856 }
2857 
2858 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2859 				  struct sk_buff_head *frames)
2860 {
2861 	ieee80211_rx_result res = RX_DROP_MONITOR;
2862 	struct sk_buff *skb;
2863 
2864 #define CALL_RXH(rxh)			\
2865 	do {				\
2866 		res = rxh(rx);		\
2867 		if (res != RX_CONTINUE)	\
2868 			goto rxh_next;  \
2869 	} while (0);
2870 
2871 	spin_lock_bh(&rx->local->rx_path_lock);
2872 
2873 	while ((skb = __skb_dequeue(frames))) {
2874 		/*
2875 		 * all the other fields are valid across frames
2876 		 * that belong to an aMPDU since they are on the
2877 		 * same TID from the same station
2878 		 */
2879 		rx->skb = skb;
2880 
2881 		CALL_RXH(ieee80211_rx_h_decrypt)
2882 		CALL_RXH(ieee80211_rx_h_check_more_data)
2883 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2884 		CALL_RXH(ieee80211_rx_h_sta_process)
2885 		CALL_RXH(ieee80211_rx_h_defragment)
2886 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2887 		/* must be after MMIC verify so header is counted in MPDU mic */
2888 #ifdef CONFIG_MAC80211_MESH
2889 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2890 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2891 #endif
2892 		CALL_RXH(ieee80211_rx_h_amsdu)
2893 		CALL_RXH(ieee80211_rx_h_data)
2894 
2895 		/* special treatment -- needs the queue */
2896 		res = ieee80211_rx_h_ctrl(rx, frames);
2897 		if (res != RX_CONTINUE)
2898 			goto rxh_next;
2899 
2900 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2901 		CALL_RXH(ieee80211_rx_h_action)
2902 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2903 		CALL_RXH(ieee80211_rx_h_action_return)
2904 		CALL_RXH(ieee80211_rx_h_mgmt)
2905 
2906  rxh_next:
2907 		ieee80211_rx_handlers_result(rx, res);
2908 
2909 #undef CALL_RXH
2910 	}
2911 
2912 	spin_unlock_bh(&rx->local->rx_path_lock);
2913 }
2914 
2915 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2916 {
2917 	struct sk_buff_head reorder_release;
2918 	ieee80211_rx_result res = RX_DROP_MONITOR;
2919 
2920 	__skb_queue_head_init(&reorder_release);
2921 
2922 #define CALL_RXH(rxh)			\
2923 	do {				\
2924 		res = rxh(rx);		\
2925 		if (res != RX_CONTINUE)	\
2926 			goto rxh_next;  \
2927 	} while (0);
2928 
2929 	CALL_RXH(ieee80211_rx_h_check)
2930 
2931 	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2932 
2933 	ieee80211_rx_handlers(rx, &reorder_release);
2934 	return;
2935 
2936  rxh_next:
2937 	ieee80211_rx_handlers_result(rx, res);
2938 
2939 #undef CALL_RXH
2940 }
2941 
2942 /*
2943  * This function makes calls into the RX path, therefore
2944  * it has to be invoked under RCU read lock.
2945  */
2946 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2947 {
2948 	struct sk_buff_head frames;
2949 	struct ieee80211_rx_data rx = {
2950 		.sta = sta,
2951 		.sdata = sta->sdata,
2952 		.local = sta->local,
2953 		/* This is OK -- must be QoS data frame */
2954 		.security_idx = tid,
2955 		.seqno_idx = tid,
2956 		.flags = 0,
2957 	};
2958 	struct tid_ampdu_rx *tid_agg_rx;
2959 
2960 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2961 	if (!tid_agg_rx)
2962 		return;
2963 
2964 	__skb_queue_head_init(&frames);
2965 
2966 	spin_lock(&tid_agg_rx->reorder_lock);
2967 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2968 	spin_unlock(&tid_agg_rx->reorder_lock);
2969 
2970 	ieee80211_rx_handlers(&rx, &frames);
2971 }
2972 
2973 /* main receive path */
2974 
2975 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2976 				struct ieee80211_hdr *hdr)
2977 {
2978 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2979 	struct sk_buff *skb = rx->skb;
2980 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2981 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2982 	int multicast = is_multicast_ether_addr(hdr->addr1);
2983 
2984 	switch (sdata->vif.type) {
2985 	case NL80211_IFTYPE_STATION:
2986 		if (!bssid && !sdata->u.mgd.use_4addr)
2987 			return 0;
2988 		if (!multicast &&
2989 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2990 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2991 			    sdata->u.mgd.use_4addr)
2992 				return 0;
2993 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2994 		}
2995 		break;
2996 	case NL80211_IFTYPE_ADHOC:
2997 		if (!bssid)
2998 			return 0;
2999 		if (ieee80211_is_beacon(hdr->frame_control)) {
3000 			return 1;
3001 		} else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3002 			return 0;
3003 		} else if (!multicast &&
3004 			   !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3005 			if (!(sdata->dev->flags & IFF_PROMISC))
3006 				return 0;
3007 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3008 		} else if (!rx->sta) {
3009 			int rate_idx;
3010 			if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3011 				rate_idx = 0; /* TODO: HT/VHT rates */
3012 			else
3013 				rate_idx = status->rate_idx;
3014 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3015 						 BIT(rate_idx));
3016 		}
3017 		break;
3018 	case NL80211_IFTYPE_MESH_POINT:
3019 		if (!multicast &&
3020 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3021 			if (!(sdata->dev->flags & IFF_PROMISC))
3022 				return 0;
3023 
3024 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3025 		}
3026 		break;
3027 	case NL80211_IFTYPE_AP_VLAN:
3028 	case NL80211_IFTYPE_AP:
3029 		if (!bssid) {
3030 			if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3031 				return 0;
3032 		} else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3033 			/*
3034 			 * Accept public action frames even when the
3035 			 * BSSID doesn't match, this is used for P2P
3036 			 * and location updates. Note that mac80211
3037 			 * itself never looks at these frames.
3038 			 */
3039 			if (!multicast &&
3040 			    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3041 				return 0;
3042 			if (ieee80211_is_public_action(hdr, skb->len))
3043 				return 1;
3044 			if (!ieee80211_is_beacon(hdr->frame_control))
3045 				return 0;
3046 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3047 		}
3048 		break;
3049 	case NL80211_IFTYPE_WDS:
3050 		if (bssid || !ieee80211_is_data(hdr->frame_control))
3051 			return 0;
3052 		if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3053 			return 0;
3054 		break;
3055 	case NL80211_IFTYPE_P2P_DEVICE:
3056 		if (!ieee80211_is_public_action(hdr, skb->len) &&
3057 		    !ieee80211_is_probe_req(hdr->frame_control) &&
3058 		    !ieee80211_is_probe_resp(hdr->frame_control) &&
3059 		    !ieee80211_is_beacon(hdr->frame_control))
3060 			return 0;
3061 		if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3062 		    !multicast)
3063 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3064 		break;
3065 	default:
3066 		/* should never get here */
3067 		WARN_ON_ONCE(1);
3068 		break;
3069 	}
3070 
3071 	return 1;
3072 }
3073 
3074 /*
3075  * This function returns whether or not the SKB
3076  * was destined for RX processing or not, which,
3077  * if consume is true, is equivalent to whether
3078  * or not the skb was consumed.
3079  */
3080 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3081 					    struct sk_buff *skb, bool consume)
3082 {
3083 	struct ieee80211_local *local = rx->local;
3084 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3085 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3086 	struct ieee80211_hdr *hdr = (void *)skb->data;
3087 	int prepares;
3088 
3089 	rx->skb = skb;
3090 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
3091 	prepares = prepare_for_handlers(rx, hdr);
3092 
3093 	if (!prepares)
3094 		return false;
3095 
3096 	if (!consume) {
3097 		skb = skb_copy(skb, GFP_ATOMIC);
3098 		if (!skb) {
3099 			if (net_ratelimit())
3100 				wiphy_debug(local->hw.wiphy,
3101 					"failed to copy skb for %s\n",
3102 					sdata->name);
3103 			return true;
3104 		}
3105 
3106 		rx->skb = skb;
3107 	}
3108 
3109 	ieee80211_invoke_rx_handlers(rx);
3110 	return true;
3111 }
3112 
3113 /*
3114  * This is the actual Rx frames handler. as it blongs to Rx path it must
3115  * be called with rcu_read_lock protection.
3116  */
3117 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3118 					 struct sk_buff *skb)
3119 {
3120 	struct ieee80211_local *local = hw_to_local(hw);
3121 	struct ieee80211_sub_if_data *sdata;
3122 	struct ieee80211_hdr *hdr;
3123 	__le16 fc;
3124 	struct ieee80211_rx_data rx;
3125 	struct ieee80211_sub_if_data *prev;
3126 	struct sta_info *sta, *tmp, *prev_sta;
3127 	int err = 0;
3128 
3129 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3130 	memset(&rx, 0, sizeof(rx));
3131 	rx.skb = skb;
3132 	rx.local = local;
3133 
3134 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3135 		local->dot11ReceivedFragmentCount++;
3136 
3137 	if (ieee80211_is_mgmt(fc)) {
3138 		/* drop frame if too short for header */
3139 		if (skb->len < ieee80211_hdrlen(fc))
3140 			err = -ENOBUFS;
3141 		else
3142 			err = skb_linearize(skb);
3143 	} else {
3144 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3145 	}
3146 
3147 	if (err) {
3148 		dev_kfree_skb(skb);
3149 		return;
3150 	}
3151 
3152 	hdr = (struct ieee80211_hdr *)skb->data;
3153 	ieee80211_parse_qos(&rx);
3154 	ieee80211_verify_alignment(&rx);
3155 
3156 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3157 		     ieee80211_is_beacon(hdr->frame_control)))
3158 		ieee80211_scan_rx(local, skb);
3159 
3160 	if (ieee80211_is_data(fc)) {
3161 		prev_sta = NULL;
3162 
3163 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
3164 			if (!prev_sta) {
3165 				prev_sta = sta;
3166 				continue;
3167 			}
3168 
3169 			rx.sta = prev_sta;
3170 			rx.sdata = prev_sta->sdata;
3171 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
3172 
3173 			prev_sta = sta;
3174 		}
3175 
3176 		if (prev_sta) {
3177 			rx.sta = prev_sta;
3178 			rx.sdata = prev_sta->sdata;
3179 
3180 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3181 				return;
3182 			goto out;
3183 		}
3184 	}
3185 
3186 	prev = NULL;
3187 
3188 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3189 		if (!ieee80211_sdata_running(sdata))
3190 			continue;
3191 
3192 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3193 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3194 			continue;
3195 
3196 		/*
3197 		 * frame is destined for this interface, but if it's
3198 		 * not also for the previous one we handle that after
3199 		 * the loop to avoid copying the SKB once too much
3200 		 */
3201 
3202 		if (!prev) {
3203 			prev = sdata;
3204 			continue;
3205 		}
3206 
3207 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3208 		rx.sdata = prev;
3209 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
3210 
3211 		prev = sdata;
3212 	}
3213 
3214 	if (prev) {
3215 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3216 		rx.sdata = prev;
3217 
3218 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3219 			return;
3220 	}
3221 
3222  out:
3223 	dev_kfree_skb(skb);
3224 }
3225 
3226 /*
3227  * This is the receive path handler. It is called by a low level driver when an
3228  * 802.11 MPDU is received from the hardware.
3229  */
3230 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3231 {
3232 	struct ieee80211_local *local = hw_to_local(hw);
3233 	struct ieee80211_rate *rate = NULL;
3234 	struct ieee80211_supported_band *sband;
3235 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3236 
3237 	WARN_ON_ONCE(softirq_count() == 0);
3238 
3239 	if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3240 		goto drop;
3241 
3242 	sband = local->hw.wiphy->bands[status->band];
3243 	if (WARN_ON(!sband))
3244 		goto drop;
3245 
3246 	/*
3247 	 * If we're suspending, it is possible although not too likely
3248 	 * that we'd be receiving frames after having already partially
3249 	 * quiesced the stack. We can't process such frames then since
3250 	 * that might, for example, cause stations to be added or other
3251 	 * driver callbacks be invoked.
3252 	 */
3253 	if (unlikely(local->quiescing || local->suspended))
3254 		goto drop;
3255 
3256 	/* We might be during a HW reconfig, prevent Rx for the same reason */
3257 	if (unlikely(local->in_reconfig))
3258 		goto drop;
3259 
3260 	/*
3261 	 * The same happens when we're not even started,
3262 	 * but that's worth a warning.
3263 	 */
3264 	if (WARN_ON(!local->started))
3265 		goto drop;
3266 
3267 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3268 		/*
3269 		 * Validate the rate, unless a PLCP error means that
3270 		 * we probably can't have a valid rate here anyway.
3271 		 */
3272 
3273 		if (status->flag & RX_FLAG_HT) {
3274 			/*
3275 			 * rate_idx is MCS index, which can be [0-76]
3276 			 * as documented on:
3277 			 *
3278 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3279 			 *
3280 			 * Anything else would be some sort of driver or
3281 			 * hardware error. The driver should catch hardware
3282 			 * errors.
3283 			 */
3284 			if (WARN(status->rate_idx > 76,
3285 				 "Rate marked as an HT rate but passed "
3286 				 "status->rate_idx is not "
3287 				 "an MCS index [0-76]: %d (0x%02x)\n",
3288 				 status->rate_idx,
3289 				 status->rate_idx))
3290 				goto drop;
3291 		} else if (status->flag & RX_FLAG_VHT) {
3292 			if (WARN_ONCE(status->rate_idx > 9 ||
3293 				      !status->vht_nss ||
3294 				      status->vht_nss > 8,
3295 				      "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3296 				      status->rate_idx, status->vht_nss))
3297 				goto drop;
3298 		} else {
3299 			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3300 				goto drop;
3301 			rate = &sband->bitrates[status->rate_idx];
3302 		}
3303 	}
3304 
3305 	status->rx_flags = 0;
3306 
3307 	/*
3308 	 * key references and virtual interfaces are protected using RCU
3309 	 * and this requires that we are in a read-side RCU section during
3310 	 * receive processing
3311 	 */
3312 	rcu_read_lock();
3313 
3314 	/*
3315 	 * Frames with failed FCS/PLCP checksum are not returned,
3316 	 * all other frames are returned without radiotap header
3317 	 * if it was previously present.
3318 	 * Also, frames with less than 16 bytes are dropped.
3319 	 */
3320 	skb = ieee80211_rx_monitor(local, skb, rate);
3321 	if (!skb) {
3322 		rcu_read_unlock();
3323 		return;
3324 	}
3325 
3326 	ieee80211_tpt_led_trig_rx(local,
3327 			((struct ieee80211_hdr *)skb->data)->frame_control,
3328 			skb->len);
3329 	__ieee80211_rx_handle_packet(hw, skb);
3330 
3331 	rcu_read_unlock();
3332 
3333 	return;
3334  drop:
3335 	kfree_skb(skb);
3336 }
3337 EXPORT_SYMBOL(ieee80211_rx);
3338 
3339 /* This is a version of the rx handler that can be called from hard irq
3340  * context. Post the skb on the queue and schedule the tasklet */
3341 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3342 {
3343 	struct ieee80211_local *local = hw_to_local(hw);
3344 
3345 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3346 
3347 	skb->pkt_type = IEEE80211_RX_MSG;
3348 	skb_queue_tail(&local->skb_queue, skb);
3349 	tasklet_schedule(&local->tasklet);
3350 }
3351 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3352