xref: /openbmc/linux/net/mac80211/rx.c (revision 95e9fd10)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <linux/export.h>
20 #include <net/mac80211.h>
21 #include <net/ieee80211_radiotap.h>
22 #include <asm/unaligned.h>
23 
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "led.h"
27 #include "mesh.h"
28 #include "wep.h"
29 #include "wpa.h"
30 #include "tkip.h"
31 #include "wme.h"
32 #include "rate.h"
33 
34 /*
35  * monitor mode reception
36  *
37  * This function cleans up the SKB, i.e. it removes all the stuff
38  * only useful for monitoring.
39  */
40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
41 					   struct sk_buff *skb)
42 {
43 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
44 		if (likely(skb->len > FCS_LEN))
45 			__pskb_trim(skb, skb->len - FCS_LEN);
46 		else {
47 			/* driver bug */
48 			WARN_ON(1);
49 			dev_kfree_skb(skb);
50 			skb = NULL;
51 		}
52 	}
53 
54 	return skb;
55 }
56 
57 static inline int should_drop_frame(struct sk_buff *skb,
58 				    int present_fcs_len)
59 {
60 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
61 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
62 
63 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
64 		return 1;
65 	if (unlikely(skb->len < 16 + present_fcs_len))
66 		return 1;
67 	if (ieee80211_is_ctl(hdr->frame_control) &&
68 	    !ieee80211_is_pspoll(hdr->frame_control) &&
69 	    !ieee80211_is_back_req(hdr->frame_control))
70 		return 1;
71 	return 0;
72 }
73 
74 static int
75 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
76 			  struct ieee80211_rx_status *status)
77 {
78 	int len;
79 
80 	/* always present fields */
81 	len = sizeof(struct ieee80211_radiotap_header) + 9;
82 
83 	if (status->flag & RX_FLAG_MACTIME_MPDU)
84 		len += 8;
85 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
86 		len += 1;
87 
88 	if (len & 1) /* padding for RX_FLAGS if necessary */
89 		len++;
90 
91 	if (status->flag & RX_FLAG_HT) /* HT info */
92 		len += 3;
93 
94 	return len;
95 }
96 
97 /**
98  * ieee80211_add_rx_radiotap_header - add radiotap header
99  *
100  * add a radiotap header containing all the fields which the hardware provided.
101  */
102 static void
103 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
104 				 struct sk_buff *skb,
105 				 struct ieee80211_rate *rate,
106 				 int rtap_len, bool has_fcs)
107 {
108 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
109 	struct ieee80211_radiotap_header *rthdr;
110 	unsigned char *pos;
111 	u16 rx_flags = 0;
112 
113 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
114 	memset(rthdr, 0, rtap_len);
115 
116 	/* radiotap header, set always present flags */
117 	rthdr->it_present =
118 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
119 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
120 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
121 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
122 	rthdr->it_len = cpu_to_le16(rtap_len);
123 
124 	pos = (unsigned char *)(rthdr+1);
125 
126 	/* the order of the following fields is important */
127 
128 	/* IEEE80211_RADIOTAP_TSFT */
129 	if (status->flag & RX_FLAG_MACTIME_MPDU) {
130 		put_unaligned_le64(status->mactime, pos);
131 		rthdr->it_present |=
132 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
133 		pos += 8;
134 	}
135 
136 	/* IEEE80211_RADIOTAP_FLAGS */
137 	if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
138 		*pos |= IEEE80211_RADIOTAP_F_FCS;
139 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
140 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
141 	if (status->flag & RX_FLAG_SHORTPRE)
142 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
143 	pos++;
144 
145 	/* IEEE80211_RADIOTAP_RATE */
146 	if (!rate || status->flag & RX_FLAG_HT) {
147 		/*
148 		 * Without rate information don't add it. If we have,
149 		 * MCS information is a separate field in radiotap,
150 		 * added below. The byte here is needed as padding
151 		 * for the channel though, so initialise it to 0.
152 		 */
153 		*pos = 0;
154 	} else {
155 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
156 		*pos = rate->bitrate / 5;
157 	}
158 	pos++;
159 
160 	/* IEEE80211_RADIOTAP_CHANNEL */
161 	put_unaligned_le16(status->freq, pos);
162 	pos += 2;
163 	if (status->band == IEEE80211_BAND_5GHZ)
164 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
165 				   pos);
166 	else if (status->flag & RX_FLAG_HT)
167 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
168 				   pos);
169 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
170 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
171 				   pos);
172 	else if (rate)
173 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
174 				   pos);
175 	else
176 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
177 	pos += 2;
178 
179 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
180 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
181 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
182 		*pos = status->signal;
183 		rthdr->it_present |=
184 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
185 		pos++;
186 	}
187 
188 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
189 
190 	/* IEEE80211_RADIOTAP_ANTENNA */
191 	*pos = status->antenna;
192 	pos++;
193 
194 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
195 
196 	/* IEEE80211_RADIOTAP_RX_FLAGS */
197 	/* ensure 2 byte alignment for the 2 byte field as required */
198 	if ((pos - (u8 *)rthdr) & 1)
199 		pos++;
200 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
201 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
202 	put_unaligned_le16(rx_flags, pos);
203 	pos += 2;
204 
205 	if (status->flag & RX_FLAG_HT) {
206 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
207 		*pos++ = local->hw.radiotap_mcs_details;
208 		*pos = 0;
209 		if (status->flag & RX_FLAG_SHORT_GI)
210 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
211 		if (status->flag & RX_FLAG_40MHZ)
212 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
213 		if (status->flag & RX_FLAG_HT_GF)
214 			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
215 		pos++;
216 		*pos++ = status->rate_idx;
217 	}
218 }
219 
220 /*
221  * This function copies a received frame to all monitor interfaces and
222  * returns a cleaned-up SKB that no longer includes the FCS nor the
223  * radiotap header the driver might have added.
224  */
225 static struct sk_buff *
226 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
227 		     struct ieee80211_rate *rate)
228 {
229 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
230 	struct ieee80211_sub_if_data *sdata;
231 	int needed_headroom;
232 	struct sk_buff *skb, *skb2;
233 	struct net_device *prev_dev = NULL;
234 	int present_fcs_len = 0;
235 
236 	/*
237 	 * First, we may need to make a copy of the skb because
238 	 *  (1) we need to modify it for radiotap (if not present), and
239 	 *  (2) the other RX handlers will modify the skb we got.
240 	 *
241 	 * We don't need to, of course, if we aren't going to return
242 	 * the SKB because it has a bad FCS/PLCP checksum.
243 	 */
244 
245 	/* room for the radiotap header based on driver features */
246 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
247 
248 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
249 		present_fcs_len = FCS_LEN;
250 
251 	/* make sure hdr->frame_control is on the linear part */
252 	if (!pskb_may_pull(origskb, 2)) {
253 		dev_kfree_skb(origskb);
254 		return NULL;
255 	}
256 
257 	if (!local->monitors) {
258 		if (should_drop_frame(origskb, present_fcs_len)) {
259 			dev_kfree_skb(origskb);
260 			return NULL;
261 		}
262 
263 		return remove_monitor_info(local, origskb);
264 	}
265 
266 	if (should_drop_frame(origskb, present_fcs_len)) {
267 		/* only need to expand headroom if necessary */
268 		skb = origskb;
269 		origskb = NULL;
270 
271 		/*
272 		 * This shouldn't trigger often because most devices have an
273 		 * RX header they pull before we get here, and that should
274 		 * be big enough for our radiotap information. We should
275 		 * probably export the length to drivers so that we can have
276 		 * them allocate enough headroom to start with.
277 		 */
278 		if (skb_headroom(skb) < needed_headroom &&
279 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
280 			dev_kfree_skb(skb);
281 			return NULL;
282 		}
283 	} else {
284 		/*
285 		 * Need to make a copy and possibly remove radiotap header
286 		 * and FCS from the original.
287 		 */
288 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
289 
290 		origskb = remove_monitor_info(local, origskb);
291 
292 		if (!skb)
293 			return origskb;
294 	}
295 
296 	/* prepend radiotap information */
297 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
298 					 true);
299 
300 	skb_reset_mac_header(skb);
301 	skb->ip_summed = CHECKSUM_UNNECESSARY;
302 	skb->pkt_type = PACKET_OTHERHOST;
303 	skb->protocol = htons(ETH_P_802_2);
304 
305 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
306 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
307 			continue;
308 
309 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
310 			continue;
311 
312 		if (!ieee80211_sdata_running(sdata))
313 			continue;
314 
315 		if (prev_dev) {
316 			skb2 = skb_clone(skb, GFP_ATOMIC);
317 			if (skb2) {
318 				skb2->dev = prev_dev;
319 				netif_receive_skb(skb2);
320 			}
321 		}
322 
323 		prev_dev = sdata->dev;
324 		sdata->dev->stats.rx_packets++;
325 		sdata->dev->stats.rx_bytes += skb->len;
326 	}
327 
328 	if (prev_dev) {
329 		skb->dev = prev_dev;
330 		netif_receive_skb(skb);
331 	} else
332 		dev_kfree_skb(skb);
333 
334 	return origskb;
335 }
336 
337 
338 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
339 {
340 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
341 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
342 	int tid, seqno_idx, security_idx;
343 
344 	/* does the frame have a qos control field? */
345 	if (ieee80211_is_data_qos(hdr->frame_control)) {
346 		u8 *qc = ieee80211_get_qos_ctl(hdr);
347 		/* frame has qos control */
348 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
349 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
350 			status->rx_flags |= IEEE80211_RX_AMSDU;
351 
352 		seqno_idx = tid;
353 		security_idx = tid;
354 	} else {
355 		/*
356 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
357 		 *
358 		 *	Sequence numbers for management frames, QoS data
359 		 *	frames with a broadcast/multicast address in the
360 		 *	Address 1 field, and all non-QoS data frames sent
361 		 *	by QoS STAs are assigned using an additional single
362 		 *	modulo-4096 counter, [...]
363 		 *
364 		 * We also use that counter for non-QoS STAs.
365 		 */
366 		seqno_idx = NUM_RX_DATA_QUEUES;
367 		security_idx = 0;
368 		if (ieee80211_is_mgmt(hdr->frame_control))
369 			security_idx = NUM_RX_DATA_QUEUES;
370 		tid = 0;
371 	}
372 
373 	rx->seqno_idx = seqno_idx;
374 	rx->security_idx = security_idx;
375 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
376 	 * For now, set skb->priority to 0 for other cases. */
377 	rx->skb->priority = (tid > 7) ? 0 : tid;
378 }
379 
380 /**
381  * DOC: Packet alignment
382  *
383  * Drivers always need to pass packets that are aligned to two-byte boundaries
384  * to the stack.
385  *
386  * Additionally, should, if possible, align the payload data in a way that
387  * guarantees that the contained IP header is aligned to a four-byte
388  * boundary. In the case of regular frames, this simply means aligning the
389  * payload to a four-byte boundary (because either the IP header is directly
390  * contained, or IV/RFC1042 headers that have a length divisible by four are
391  * in front of it).  If the payload data is not properly aligned and the
392  * architecture doesn't support efficient unaligned operations, mac80211
393  * will align the data.
394  *
395  * With A-MSDU frames, however, the payload data address must yield two modulo
396  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
397  * push the IP header further back to a multiple of four again. Thankfully, the
398  * specs were sane enough this time around to require padding each A-MSDU
399  * subframe to a length that is a multiple of four.
400  *
401  * Padding like Atheros hardware adds which is between the 802.11 header and
402  * the payload is not supported, the driver is required to move the 802.11
403  * header to be directly in front of the payload in that case.
404  */
405 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
406 {
407 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
408 	WARN_ONCE((unsigned long)rx->skb->data & 1,
409 		  "unaligned packet at 0x%p\n", rx->skb->data);
410 #endif
411 }
412 
413 
414 /* rx handlers */
415 
416 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
417 {
418 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
419 
420 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
421 		return 0;
422 
423 	return ieee80211_is_robust_mgmt_frame(hdr);
424 }
425 
426 
427 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
428 {
429 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
430 
431 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
432 		return 0;
433 
434 	return ieee80211_is_robust_mgmt_frame(hdr);
435 }
436 
437 
438 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
439 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
440 {
441 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
442 	struct ieee80211_mmie *mmie;
443 
444 	if (skb->len < 24 + sizeof(*mmie) ||
445 	    !is_multicast_ether_addr(hdr->da))
446 		return -1;
447 
448 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
449 		return -1; /* not a robust management frame */
450 
451 	mmie = (struct ieee80211_mmie *)
452 		(skb->data + skb->len - sizeof(*mmie));
453 	if (mmie->element_id != WLAN_EID_MMIE ||
454 	    mmie->length != sizeof(*mmie) - 2)
455 		return -1;
456 
457 	return le16_to_cpu(mmie->key_id);
458 }
459 
460 
461 static ieee80211_rx_result
462 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
463 {
464 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
465 	char *dev_addr = rx->sdata->vif.addr;
466 
467 	if (ieee80211_is_data(hdr->frame_control)) {
468 		if (is_multicast_ether_addr(hdr->addr1)) {
469 			if (ieee80211_has_tods(hdr->frame_control) ||
470 				!ieee80211_has_fromds(hdr->frame_control))
471 				return RX_DROP_MONITOR;
472 			if (ether_addr_equal(hdr->addr3, dev_addr))
473 				return RX_DROP_MONITOR;
474 		} else {
475 			if (!ieee80211_has_a4(hdr->frame_control))
476 				return RX_DROP_MONITOR;
477 			if (ether_addr_equal(hdr->addr4, dev_addr))
478 				return RX_DROP_MONITOR;
479 		}
480 	}
481 
482 	/* If there is not an established peer link and this is not a peer link
483 	 * establisment frame, beacon or probe, drop the frame.
484 	 */
485 
486 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
487 		struct ieee80211_mgmt *mgmt;
488 
489 		if (!ieee80211_is_mgmt(hdr->frame_control))
490 			return RX_DROP_MONITOR;
491 
492 		if (ieee80211_is_action(hdr->frame_control)) {
493 			u8 category;
494 			mgmt = (struct ieee80211_mgmt *)hdr;
495 			category = mgmt->u.action.category;
496 			if (category != WLAN_CATEGORY_MESH_ACTION &&
497 				category != WLAN_CATEGORY_SELF_PROTECTED)
498 				return RX_DROP_MONITOR;
499 			return RX_CONTINUE;
500 		}
501 
502 		if (ieee80211_is_probe_req(hdr->frame_control) ||
503 		    ieee80211_is_probe_resp(hdr->frame_control) ||
504 		    ieee80211_is_beacon(hdr->frame_control) ||
505 		    ieee80211_is_auth(hdr->frame_control))
506 			return RX_CONTINUE;
507 
508 		return RX_DROP_MONITOR;
509 
510 	}
511 
512 	return RX_CONTINUE;
513 }
514 
515 #define SEQ_MODULO 0x1000
516 #define SEQ_MASK   0xfff
517 
518 static inline int seq_less(u16 sq1, u16 sq2)
519 {
520 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
521 }
522 
523 static inline u16 seq_inc(u16 sq)
524 {
525 	return (sq + 1) & SEQ_MASK;
526 }
527 
528 static inline u16 seq_sub(u16 sq1, u16 sq2)
529 {
530 	return (sq1 - sq2) & SEQ_MASK;
531 }
532 
533 
534 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
535 					    struct tid_ampdu_rx *tid_agg_rx,
536 					    int index)
537 {
538 	struct ieee80211_local *local = sdata->local;
539 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
540 	struct ieee80211_rx_status *status;
541 
542 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
543 
544 	if (!skb)
545 		goto no_frame;
546 
547 	/* release the frame from the reorder ring buffer */
548 	tid_agg_rx->stored_mpdu_num--;
549 	tid_agg_rx->reorder_buf[index] = NULL;
550 	status = IEEE80211_SKB_RXCB(skb);
551 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
552 	skb_queue_tail(&local->rx_skb_queue, skb);
553 
554 no_frame:
555 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
556 }
557 
558 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
559 					     struct tid_ampdu_rx *tid_agg_rx,
560 					     u16 head_seq_num)
561 {
562 	int index;
563 
564 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
565 
566 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
567 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
568 							tid_agg_rx->buf_size;
569 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
570 	}
571 }
572 
573 /*
574  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
575  * the skb was added to the buffer longer than this time ago, the earlier
576  * frames that have not yet been received are assumed to be lost and the skb
577  * can be released for processing. This may also release other skb's from the
578  * reorder buffer if there are no additional gaps between the frames.
579  *
580  * Callers must hold tid_agg_rx->reorder_lock.
581  */
582 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
583 
584 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
585 					  struct tid_ampdu_rx *tid_agg_rx)
586 {
587 	int index, j;
588 
589 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
590 
591 	/* release the buffer until next missing frame */
592 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
593 						tid_agg_rx->buf_size;
594 	if (!tid_agg_rx->reorder_buf[index] &&
595 	    tid_agg_rx->stored_mpdu_num) {
596 		/*
597 		 * No buffers ready to be released, but check whether any
598 		 * frames in the reorder buffer have timed out.
599 		 */
600 		int skipped = 1;
601 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
602 		     j = (j + 1) % tid_agg_rx->buf_size) {
603 			if (!tid_agg_rx->reorder_buf[j]) {
604 				skipped++;
605 				continue;
606 			}
607 			if (skipped &&
608 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
609 					HT_RX_REORDER_BUF_TIMEOUT))
610 				goto set_release_timer;
611 
612 			ht_dbg_ratelimited(sdata,
613 					   "release an RX reorder frame due to timeout on earlier frames\n");
614 			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j);
615 
616 			/*
617 			 * Increment the head seq# also for the skipped slots.
618 			 */
619 			tid_agg_rx->head_seq_num =
620 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
621 			skipped = 0;
622 		}
623 	} else while (tid_agg_rx->reorder_buf[index]) {
624 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
625 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
626 							tid_agg_rx->buf_size;
627 	}
628 
629 	if (tid_agg_rx->stored_mpdu_num) {
630 		j = index = seq_sub(tid_agg_rx->head_seq_num,
631 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
632 
633 		for (; j != (index - 1) % tid_agg_rx->buf_size;
634 		     j = (j + 1) % tid_agg_rx->buf_size) {
635 			if (tid_agg_rx->reorder_buf[j])
636 				break;
637 		}
638 
639  set_release_timer:
640 
641 		mod_timer(&tid_agg_rx->reorder_timer,
642 			  tid_agg_rx->reorder_time[j] + 1 +
643 			  HT_RX_REORDER_BUF_TIMEOUT);
644 	} else {
645 		del_timer(&tid_agg_rx->reorder_timer);
646 	}
647 }
648 
649 /*
650  * As this function belongs to the RX path it must be under
651  * rcu_read_lock protection. It returns false if the frame
652  * can be processed immediately, true if it was consumed.
653  */
654 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
655 					     struct tid_ampdu_rx *tid_agg_rx,
656 					     struct sk_buff *skb)
657 {
658 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
659 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
660 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
661 	u16 head_seq_num, buf_size;
662 	int index;
663 	bool ret = true;
664 
665 	spin_lock(&tid_agg_rx->reorder_lock);
666 
667 	buf_size = tid_agg_rx->buf_size;
668 	head_seq_num = tid_agg_rx->head_seq_num;
669 
670 	/* frame with out of date sequence number */
671 	if (seq_less(mpdu_seq_num, head_seq_num)) {
672 		dev_kfree_skb(skb);
673 		goto out;
674 	}
675 
676 	/*
677 	 * If frame the sequence number exceeds our buffering window
678 	 * size release some previous frames to make room for this one.
679 	 */
680 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
681 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
682 		/* release stored frames up to new head to stack */
683 		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
684 						 head_seq_num);
685 	}
686 
687 	/* Now the new frame is always in the range of the reordering buffer */
688 
689 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
690 
691 	/* check if we already stored this frame */
692 	if (tid_agg_rx->reorder_buf[index]) {
693 		dev_kfree_skb(skb);
694 		goto out;
695 	}
696 
697 	/*
698 	 * If the current MPDU is in the right order and nothing else
699 	 * is stored we can process it directly, no need to buffer it.
700 	 * If it is first but there's something stored, we may be able
701 	 * to release frames after this one.
702 	 */
703 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
704 	    tid_agg_rx->stored_mpdu_num == 0) {
705 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
706 		ret = false;
707 		goto out;
708 	}
709 
710 	/* put the frame in the reordering buffer */
711 	tid_agg_rx->reorder_buf[index] = skb;
712 	tid_agg_rx->reorder_time[index] = jiffies;
713 	tid_agg_rx->stored_mpdu_num++;
714 	ieee80211_sta_reorder_release(sdata, tid_agg_rx);
715 
716  out:
717 	spin_unlock(&tid_agg_rx->reorder_lock);
718 	return ret;
719 }
720 
721 /*
722  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
723  * true if the MPDU was buffered, false if it should be processed.
724  */
725 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
726 {
727 	struct sk_buff *skb = rx->skb;
728 	struct ieee80211_local *local = rx->local;
729 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
730 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
731 	struct sta_info *sta = rx->sta;
732 	struct tid_ampdu_rx *tid_agg_rx;
733 	u16 sc;
734 	u8 tid, ack_policy;
735 
736 	if (!ieee80211_is_data_qos(hdr->frame_control))
737 		goto dont_reorder;
738 
739 	/*
740 	 * filter the QoS data rx stream according to
741 	 * STA/TID and check if this STA/TID is on aggregation
742 	 */
743 
744 	if (!sta)
745 		goto dont_reorder;
746 
747 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
748 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
749 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
750 
751 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
752 	if (!tid_agg_rx)
753 		goto dont_reorder;
754 
755 	/* qos null data frames are excluded */
756 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
757 		goto dont_reorder;
758 
759 	/* not part of a BA session */
760 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
761 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
762 		goto dont_reorder;
763 
764 	/* not actually part of this BA session */
765 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
766 		goto dont_reorder;
767 
768 	/* new, potentially un-ordered, ampdu frame - process it */
769 
770 	/* reset session timer */
771 	if (tid_agg_rx->timeout)
772 		tid_agg_rx->last_rx = jiffies;
773 
774 	/* if this mpdu is fragmented - terminate rx aggregation session */
775 	sc = le16_to_cpu(hdr->seq_ctrl);
776 	if (sc & IEEE80211_SCTL_FRAG) {
777 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
778 		skb_queue_tail(&rx->sdata->skb_queue, skb);
779 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
780 		return;
781 	}
782 
783 	/*
784 	 * No locking needed -- we will only ever process one
785 	 * RX packet at a time, and thus own tid_agg_rx. All
786 	 * other code manipulating it needs to (and does) make
787 	 * sure that we cannot get to it any more before doing
788 	 * anything with it.
789 	 */
790 	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb))
791 		return;
792 
793  dont_reorder:
794 	skb_queue_tail(&local->rx_skb_queue, skb);
795 }
796 
797 static ieee80211_rx_result debug_noinline
798 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
799 {
800 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
801 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
802 
803 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
804 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
805 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
806 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
807 			     hdr->seq_ctrl)) {
808 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
809 				rx->local->dot11FrameDuplicateCount++;
810 				rx->sta->num_duplicates++;
811 			}
812 			return RX_DROP_UNUSABLE;
813 		} else
814 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
815 	}
816 
817 	if (unlikely(rx->skb->len < 16)) {
818 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
819 		return RX_DROP_MONITOR;
820 	}
821 
822 	/* Drop disallowed frame classes based on STA auth/assoc state;
823 	 * IEEE 802.11, Chap 5.5.
824 	 *
825 	 * mac80211 filters only based on association state, i.e. it drops
826 	 * Class 3 frames from not associated stations. hostapd sends
827 	 * deauth/disassoc frames when needed. In addition, hostapd is
828 	 * responsible for filtering on both auth and assoc states.
829 	 */
830 
831 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
832 		return ieee80211_rx_mesh_check(rx);
833 
834 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
835 		      ieee80211_is_pspoll(hdr->frame_control)) &&
836 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
837 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
838 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
839 		/*
840 		 * accept port control frames from the AP even when it's not
841 		 * yet marked ASSOC to prevent a race where we don't set the
842 		 * assoc bit quickly enough before it sends the first frame
843 		 */
844 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
845 		    ieee80211_is_data_present(hdr->frame_control)) {
846 			u16 ethertype;
847 			u8 *payload;
848 
849 			payload = rx->skb->data +
850 				ieee80211_hdrlen(hdr->frame_control);
851 			ethertype = (payload[6] << 8) | payload[7];
852 			if (cpu_to_be16(ethertype) ==
853 			    rx->sdata->control_port_protocol)
854 				return RX_CONTINUE;
855 		}
856 
857 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
858 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
859 					       hdr->addr2,
860 					       GFP_ATOMIC))
861 			return RX_DROP_UNUSABLE;
862 
863 		return RX_DROP_MONITOR;
864 	}
865 
866 	return RX_CONTINUE;
867 }
868 
869 
870 static ieee80211_rx_result debug_noinline
871 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
872 {
873 	struct sk_buff *skb = rx->skb;
874 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
875 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
876 	int keyidx;
877 	int hdrlen;
878 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
879 	struct ieee80211_key *sta_ptk = NULL;
880 	int mmie_keyidx = -1;
881 	__le16 fc;
882 
883 	/*
884 	 * Key selection 101
885 	 *
886 	 * There are four types of keys:
887 	 *  - GTK (group keys)
888 	 *  - IGTK (group keys for management frames)
889 	 *  - PTK (pairwise keys)
890 	 *  - STK (station-to-station pairwise keys)
891 	 *
892 	 * When selecting a key, we have to distinguish between multicast
893 	 * (including broadcast) and unicast frames, the latter can only
894 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
895 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
896 	 * unicast frames can also use key indices like GTKs. Hence, if we
897 	 * don't have a PTK/STK we check the key index for a WEP key.
898 	 *
899 	 * Note that in a regular BSS, multicast frames are sent by the
900 	 * AP only, associated stations unicast the frame to the AP first
901 	 * which then multicasts it on their behalf.
902 	 *
903 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
904 	 * with each station, that is something we don't currently handle.
905 	 * The spec seems to expect that one negotiates the same key with
906 	 * every station but there's no such requirement; VLANs could be
907 	 * possible.
908 	 */
909 
910 	/*
911 	 * No point in finding a key and decrypting if the frame is neither
912 	 * addressed to us nor a multicast frame.
913 	 */
914 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
915 		return RX_CONTINUE;
916 
917 	/* start without a key */
918 	rx->key = NULL;
919 
920 	if (rx->sta)
921 		sta_ptk = rcu_dereference(rx->sta->ptk);
922 
923 	fc = hdr->frame_control;
924 
925 	if (!ieee80211_has_protected(fc))
926 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
927 
928 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
929 		rx->key = sta_ptk;
930 		if ((status->flag & RX_FLAG_DECRYPTED) &&
931 		    (status->flag & RX_FLAG_IV_STRIPPED))
932 			return RX_CONTINUE;
933 		/* Skip decryption if the frame is not protected. */
934 		if (!ieee80211_has_protected(fc))
935 			return RX_CONTINUE;
936 	} else if (mmie_keyidx >= 0) {
937 		/* Broadcast/multicast robust management frame / BIP */
938 		if ((status->flag & RX_FLAG_DECRYPTED) &&
939 		    (status->flag & RX_FLAG_IV_STRIPPED))
940 			return RX_CONTINUE;
941 
942 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
943 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
944 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
945 		if (rx->sta)
946 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
947 		if (!rx->key)
948 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
949 	} else if (!ieee80211_has_protected(fc)) {
950 		/*
951 		 * The frame was not protected, so skip decryption. However, we
952 		 * need to set rx->key if there is a key that could have been
953 		 * used so that the frame may be dropped if encryption would
954 		 * have been expected.
955 		 */
956 		struct ieee80211_key *key = NULL;
957 		struct ieee80211_sub_if_data *sdata = rx->sdata;
958 		int i;
959 
960 		if (ieee80211_is_mgmt(fc) &&
961 		    is_multicast_ether_addr(hdr->addr1) &&
962 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
963 			rx->key = key;
964 		else {
965 			if (rx->sta) {
966 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
967 					key = rcu_dereference(rx->sta->gtk[i]);
968 					if (key)
969 						break;
970 				}
971 			}
972 			if (!key) {
973 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
974 					key = rcu_dereference(sdata->keys[i]);
975 					if (key)
976 						break;
977 				}
978 			}
979 			if (key)
980 				rx->key = key;
981 		}
982 		return RX_CONTINUE;
983 	} else {
984 		u8 keyid;
985 		/*
986 		 * The device doesn't give us the IV so we won't be
987 		 * able to look up the key. That's ok though, we
988 		 * don't need to decrypt the frame, we just won't
989 		 * be able to keep statistics accurate.
990 		 * Except for key threshold notifications, should
991 		 * we somehow allow the driver to tell us which key
992 		 * the hardware used if this flag is set?
993 		 */
994 		if ((status->flag & RX_FLAG_DECRYPTED) &&
995 		    (status->flag & RX_FLAG_IV_STRIPPED))
996 			return RX_CONTINUE;
997 
998 		hdrlen = ieee80211_hdrlen(fc);
999 
1000 		if (rx->skb->len < 8 + hdrlen)
1001 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1002 
1003 		/*
1004 		 * no need to call ieee80211_wep_get_keyidx,
1005 		 * it verifies a bunch of things we've done already
1006 		 */
1007 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1008 		keyidx = keyid >> 6;
1009 
1010 		/* check per-station GTK first, if multicast packet */
1011 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1012 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1013 
1014 		/* if not found, try default key */
1015 		if (!rx->key) {
1016 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1017 
1018 			/*
1019 			 * RSNA-protected unicast frames should always be
1020 			 * sent with pairwise or station-to-station keys,
1021 			 * but for WEP we allow using a key index as well.
1022 			 */
1023 			if (rx->key &&
1024 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1025 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1026 			    !is_multicast_ether_addr(hdr->addr1))
1027 				rx->key = NULL;
1028 		}
1029 	}
1030 
1031 	if (rx->key) {
1032 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1033 			return RX_DROP_MONITOR;
1034 
1035 		rx->key->tx_rx_count++;
1036 		/* TODO: add threshold stuff again */
1037 	} else {
1038 		return RX_DROP_MONITOR;
1039 	}
1040 
1041 	switch (rx->key->conf.cipher) {
1042 	case WLAN_CIPHER_SUITE_WEP40:
1043 	case WLAN_CIPHER_SUITE_WEP104:
1044 		result = ieee80211_crypto_wep_decrypt(rx);
1045 		break;
1046 	case WLAN_CIPHER_SUITE_TKIP:
1047 		result = ieee80211_crypto_tkip_decrypt(rx);
1048 		break;
1049 	case WLAN_CIPHER_SUITE_CCMP:
1050 		result = ieee80211_crypto_ccmp_decrypt(rx);
1051 		break;
1052 	case WLAN_CIPHER_SUITE_AES_CMAC:
1053 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1054 		break;
1055 	default:
1056 		/*
1057 		 * We can reach here only with HW-only algorithms
1058 		 * but why didn't it decrypt the frame?!
1059 		 */
1060 		return RX_DROP_UNUSABLE;
1061 	}
1062 
1063 	/* the hdr variable is invalid after the decrypt handlers */
1064 
1065 	/* either the frame has been decrypted or will be dropped */
1066 	status->flag |= RX_FLAG_DECRYPTED;
1067 
1068 	return result;
1069 }
1070 
1071 static ieee80211_rx_result debug_noinline
1072 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1073 {
1074 	struct ieee80211_local *local;
1075 	struct ieee80211_hdr *hdr;
1076 	struct sk_buff *skb;
1077 
1078 	local = rx->local;
1079 	skb = rx->skb;
1080 	hdr = (struct ieee80211_hdr *) skb->data;
1081 
1082 	if (!local->pspolling)
1083 		return RX_CONTINUE;
1084 
1085 	if (!ieee80211_has_fromds(hdr->frame_control))
1086 		/* this is not from AP */
1087 		return RX_CONTINUE;
1088 
1089 	if (!ieee80211_is_data(hdr->frame_control))
1090 		return RX_CONTINUE;
1091 
1092 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1093 		/* AP has no more frames buffered for us */
1094 		local->pspolling = false;
1095 		return RX_CONTINUE;
1096 	}
1097 
1098 	/* more data bit is set, let's request a new frame from the AP */
1099 	ieee80211_send_pspoll(local, rx->sdata);
1100 
1101 	return RX_CONTINUE;
1102 }
1103 
1104 static void ap_sta_ps_start(struct sta_info *sta)
1105 {
1106 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1107 	struct ieee80211_local *local = sdata->local;
1108 
1109 	atomic_inc(&sdata->bss->num_sta_ps);
1110 	set_sta_flag(sta, WLAN_STA_PS_STA);
1111 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1112 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1113 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1114 	       sta->sta.addr, sta->sta.aid);
1115 }
1116 
1117 static void ap_sta_ps_end(struct sta_info *sta)
1118 {
1119 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1120 	       sta->sta.addr, sta->sta.aid);
1121 
1122 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1123 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1124 		       sta->sta.addr, sta->sta.aid);
1125 		return;
1126 	}
1127 
1128 	ieee80211_sta_ps_deliver_wakeup(sta);
1129 }
1130 
1131 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1132 {
1133 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1134 	bool in_ps;
1135 
1136 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1137 
1138 	/* Don't let the same PS state be set twice */
1139 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1140 	if ((start && in_ps) || (!start && !in_ps))
1141 		return -EINVAL;
1142 
1143 	if (start)
1144 		ap_sta_ps_start(sta_inf);
1145 	else
1146 		ap_sta_ps_end(sta_inf);
1147 
1148 	return 0;
1149 }
1150 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1151 
1152 static ieee80211_rx_result debug_noinline
1153 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1154 {
1155 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1156 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1157 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1158 	int tid, ac;
1159 
1160 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1161 		return RX_CONTINUE;
1162 
1163 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1164 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1165 		return RX_CONTINUE;
1166 
1167 	/*
1168 	 * The device handles station powersave, so don't do anything about
1169 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1170 	 * it to mac80211 since they're handled.)
1171 	 */
1172 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1173 		return RX_CONTINUE;
1174 
1175 	/*
1176 	 * Don't do anything if the station isn't already asleep. In
1177 	 * the uAPSD case, the station will probably be marked asleep,
1178 	 * in the PS-Poll case the station must be confused ...
1179 	 */
1180 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1181 		return RX_CONTINUE;
1182 
1183 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1184 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1185 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1186 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1187 			else
1188 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1189 		}
1190 
1191 		/* Free PS Poll skb here instead of returning RX_DROP that would
1192 		 * count as an dropped frame. */
1193 		dev_kfree_skb(rx->skb);
1194 
1195 		return RX_QUEUED;
1196 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1197 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1198 		   ieee80211_has_pm(hdr->frame_control) &&
1199 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1200 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1201 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1202 		ac = ieee802_1d_to_ac[tid & 7];
1203 
1204 		/*
1205 		 * If this AC is not trigger-enabled do nothing.
1206 		 *
1207 		 * NB: This could/should check a separate bitmap of trigger-
1208 		 * enabled queues, but for now we only implement uAPSD w/o
1209 		 * TSPEC changes to the ACs, so they're always the same.
1210 		 */
1211 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1212 			return RX_CONTINUE;
1213 
1214 		/* if we are in a service period, do nothing */
1215 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1216 			return RX_CONTINUE;
1217 
1218 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1219 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1220 		else
1221 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1222 	}
1223 
1224 	return RX_CONTINUE;
1225 }
1226 
1227 static ieee80211_rx_result debug_noinline
1228 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1229 {
1230 	struct sta_info *sta = rx->sta;
1231 	struct sk_buff *skb = rx->skb;
1232 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1233 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1234 
1235 	if (!sta)
1236 		return RX_CONTINUE;
1237 
1238 	/*
1239 	 * Update last_rx only for IBSS packets which are for the current
1240 	 * BSSID to avoid keeping the current IBSS network alive in cases
1241 	 * where other STAs start using different BSSID.
1242 	 */
1243 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1244 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1245 						NL80211_IFTYPE_ADHOC);
1246 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid)) {
1247 			sta->last_rx = jiffies;
1248 			if (ieee80211_is_data(hdr->frame_control)) {
1249 				sta->last_rx_rate_idx = status->rate_idx;
1250 				sta->last_rx_rate_flag = status->flag;
1251 			}
1252 		}
1253 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1254 		/*
1255 		 * Mesh beacons will update last_rx when if they are found to
1256 		 * match the current local configuration when processed.
1257 		 */
1258 		sta->last_rx = jiffies;
1259 		if (ieee80211_is_data(hdr->frame_control)) {
1260 			sta->last_rx_rate_idx = status->rate_idx;
1261 			sta->last_rx_rate_flag = status->flag;
1262 		}
1263 	}
1264 
1265 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1266 		return RX_CONTINUE;
1267 
1268 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1269 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1270 
1271 	sta->rx_fragments++;
1272 	sta->rx_bytes += rx->skb->len;
1273 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1274 		sta->last_signal = status->signal;
1275 		ewma_add(&sta->avg_signal, -status->signal);
1276 	}
1277 
1278 	/*
1279 	 * Change STA power saving mode only at the end of a frame
1280 	 * exchange sequence.
1281 	 */
1282 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1283 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1284 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1285 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1286 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1287 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1288 			/*
1289 			 * Ignore doze->wake transitions that are
1290 			 * indicated by non-data frames, the standard
1291 			 * is unclear here, but for example going to
1292 			 * PS mode and then scanning would cause a
1293 			 * doze->wake transition for the probe request,
1294 			 * and that is clearly undesirable.
1295 			 */
1296 			if (ieee80211_is_data(hdr->frame_control) &&
1297 			    !ieee80211_has_pm(hdr->frame_control))
1298 				ap_sta_ps_end(sta);
1299 		} else {
1300 			if (ieee80211_has_pm(hdr->frame_control))
1301 				ap_sta_ps_start(sta);
1302 		}
1303 	}
1304 
1305 	/*
1306 	 * Drop (qos-)data::nullfunc frames silently, since they
1307 	 * are used only to control station power saving mode.
1308 	 */
1309 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1310 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1311 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1312 
1313 		/*
1314 		 * If we receive a 4-addr nullfunc frame from a STA
1315 		 * that was not moved to a 4-addr STA vlan yet send
1316 		 * the event to userspace and for older hostapd drop
1317 		 * the frame to the monitor interface.
1318 		 */
1319 		if (ieee80211_has_a4(hdr->frame_control) &&
1320 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1321 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1322 		      !rx->sdata->u.vlan.sta))) {
1323 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1324 				cfg80211_rx_unexpected_4addr_frame(
1325 					rx->sdata->dev, sta->sta.addr,
1326 					GFP_ATOMIC);
1327 			return RX_DROP_MONITOR;
1328 		}
1329 		/*
1330 		 * Update counter and free packet here to avoid
1331 		 * counting this as a dropped packed.
1332 		 */
1333 		sta->rx_packets++;
1334 		dev_kfree_skb(rx->skb);
1335 		return RX_QUEUED;
1336 	}
1337 
1338 	return RX_CONTINUE;
1339 } /* ieee80211_rx_h_sta_process */
1340 
1341 static inline struct ieee80211_fragment_entry *
1342 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1343 			 unsigned int frag, unsigned int seq, int rx_queue,
1344 			 struct sk_buff **skb)
1345 {
1346 	struct ieee80211_fragment_entry *entry;
1347 	int idx;
1348 
1349 	idx = sdata->fragment_next;
1350 	entry = &sdata->fragments[sdata->fragment_next++];
1351 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1352 		sdata->fragment_next = 0;
1353 
1354 	if (!skb_queue_empty(&entry->skb_list))
1355 		__skb_queue_purge(&entry->skb_list);
1356 
1357 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1358 	*skb = NULL;
1359 	entry->first_frag_time = jiffies;
1360 	entry->seq = seq;
1361 	entry->rx_queue = rx_queue;
1362 	entry->last_frag = frag;
1363 	entry->ccmp = 0;
1364 	entry->extra_len = 0;
1365 
1366 	return entry;
1367 }
1368 
1369 static inline struct ieee80211_fragment_entry *
1370 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1371 			  unsigned int frag, unsigned int seq,
1372 			  int rx_queue, struct ieee80211_hdr *hdr)
1373 {
1374 	struct ieee80211_fragment_entry *entry;
1375 	int i, idx;
1376 
1377 	idx = sdata->fragment_next;
1378 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1379 		struct ieee80211_hdr *f_hdr;
1380 
1381 		idx--;
1382 		if (idx < 0)
1383 			idx = IEEE80211_FRAGMENT_MAX - 1;
1384 
1385 		entry = &sdata->fragments[idx];
1386 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1387 		    entry->rx_queue != rx_queue ||
1388 		    entry->last_frag + 1 != frag)
1389 			continue;
1390 
1391 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1392 
1393 		/*
1394 		 * Check ftype and addresses are equal, else check next fragment
1395 		 */
1396 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1397 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1398 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1399 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1400 			continue;
1401 
1402 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1403 			__skb_queue_purge(&entry->skb_list);
1404 			continue;
1405 		}
1406 		return entry;
1407 	}
1408 
1409 	return NULL;
1410 }
1411 
1412 static ieee80211_rx_result debug_noinline
1413 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1414 {
1415 	struct ieee80211_hdr *hdr;
1416 	u16 sc;
1417 	__le16 fc;
1418 	unsigned int frag, seq;
1419 	struct ieee80211_fragment_entry *entry;
1420 	struct sk_buff *skb;
1421 	struct ieee80211_rx_status *status;
1422 
1423 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1424 	fc = hdr->frame_control;
1425 	sc = le16_to_cpu(hdr->seq_ctrl);
1426 	frag = sc & IEEE80211_SCTL_FRAG;
1427 
1428 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1429 		   (rx->skb)->len < 24 ||
1430 		   is_multicast_ether_addr(hdr->addr1))) {
1431 		/* not fragmented */
1432 		goto out;
1433 	}
1434 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1435 
1436 	if (skb_linearize(rx->skb))
1437 		return RX_DROP_UNUSABLE;
1438 
1439 	/*
1440 	 *  skb_linearize() might change the skb->data and
1441 	 *  previously cached variables (in this case, hdr) need to
1442 	 *  be refreshed with the new data.
1443 	 */
1444 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1445 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1446 
1447 	if (frag == 0) {
1448 		/* This is the first fragment of a new frame. */
1449 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1450 						 rx->seqno_idx, &(rx->skb));
1451 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1452 		    ieee80211_has_protected(fc)) {
1453 			int queue = rx->security_idx;
1454 			/* Store CCMP PN so that we can verify that the next
1455 			 * fragment has a sequential PN value. */
1456 			entry->ccmp = 1;
1457 			memcpy(entry->last_pn,
1458 			       rx->key->u.ccmp.rx_pn[queue],
1459 			       CCMP_PN_LEN);
1460 		}
1461 		return RX_QUEUED;
1462 	}
1463 
1464 	/* This is a fragment for a frame that should already be pending in
1465 	 * fragment cache. Add this fragment to the end of the pending entry.
1466 	 */
1467 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1468 					  rx->seqno_idx, hdr);
1469 	if (!entry) {
1470 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1471 		return RX_DROP_MONITOR;
1472 	}
1473 
1474 	/* Verify that MPDUs within one MSDU have sequential PN values.
1475 	 * (IEEE 802.11i, 8.3.3.4.5) */
1476 	if (entry->ccmp) {
1477 		int i;
1478 		u8 pn[CCMP_PN_LEN], *rpn;
1479 		int queue;
1480 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1481 			return RX_DROP_UNUSABLE;
1482 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1483 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1484 			pn[i]++;
1485 			if (pn[i])
1486 				break;
1487 		}
1488 		queue = rx->security_idx;
1489 		rpn = rx->key->u.ccmp.rx_pn[queue];
1490 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1491 			return RX_DROP_UNUSABLE;
1492 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1493 	}
1494 
1495 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1496 	__skb_queue_tail(&entry->skb_list, rx->skb);
1497 	entry->last_frag = frag;
1498 	entry->extra_len += rx->skb->len;
1499 	if (ieee80211_has_morefrags(fc)) {
1500 		rx->skb = NULL;
1501 		return RX_QUEUED;
1502 	}
1503 
1504 	rx->skb = __skb_dequeue(&entry->skb_list);
1505 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1506 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1507 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1508 					      GFP_ATOMIC))) {
1509 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1510 			__skb_queue_purge(&entry->skb_list);
1511 			return RX_DROP_UNUSABLE;
1512 		}
1513 	}
1514 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1515 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1516 		dev_kfree_skb(skb);
1517 	}
1518 
1519 	/* Complete frame has been reassembled - process it now */
1520 	status = IEEE80211_SKB_RXCB(rx->skb);
1521 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1522 
1523  out:
1524 	if (rx->sta)
1525 		rx->sta->rx_packets++;
1526 	if (is_multicast_ether_addr(hdr->addr1))
1527 		rx->local->dot11MulticastReceivedFrameCount++;
1528 	else
1529 		ieee80211_led_rx(rx->local);
1530 	return RX_CONTINUE;
1531 }
1532 
1533 static int
1534 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1535 {
1536 	if (unlikely(!rx->sta ||
1537 	    !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1538 		return -EACCES;
1539 
1540 	return 0;
1541 }
1542 
1543 static int
1544 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1545 {
1546 	struct sk_buff *skb = rx->skb;
1547 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1548 
1549 	/*
1550 	 * Pass through unencrypted frames if the hardware has
1551 	 * decrypted them already.
1552 	 */
1553 	if (status->flag & RX_FLAG_DECRYPTED)
1554 		return 0;
1555 
1556 	/* Drop unencrypted frames if key is set. */
1557 	if (unlikely(!ieee80211_has_protected(fc) &&
1558 		     !ieee80211_is_nullfunc(fc) &&
1559 		     ieee80211_is_data(fc) &&
1560 		     (rx->key || rx->sdata->drop_unencrypted)))
1561 		return -EACCES;
1562 
1563 	return 0;
1564 }
1565 
1566 static int
1567 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1568 {
1569 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1570 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1571 	__le16 fc = hdr->frame_control;
1572 
1573 	/*
1574 	 * Pass through unencrypted frames if the hardware has
1575 	 * decrypted them already.
1576 	 */
1577 	if (status->flag & RX_FLAG_DECRYPTED)
1578 		return 0;
1579 
1580 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1581 		if (unlikely(!ieee80211_has_protected(fc) &&
1582 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1583 			     rx->key)) {
1584 			if (ieee80211_is_deauth(fc))
1585 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1586 							    rx->skb->data,
1587 							    rx->skb->len);
1588 			else if (ieee80211_is_disassoc(fc))
1589 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1590 							      rx->skb->data,
1591 							      rx->skb->len);
1592 			return -EACCES;
1593 		}
1594 		/* BIP does not use Protected field, so need to check MMIE */
1595 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1596 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1597 			if (ieee80211_is_deauth(fc))
1598 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1599 							    rx->skb->data,
1600 							    rx->skb->len);
1601 			else if (ieee80211_is_disassoc(fc))
1602 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1603 							      rx->skb->data,
1604 							      rx->skb->len);
1605 			return -EACCES;
1606 		}
1607 		/*
1608 		 * When using MFP, Action frames are not allowed prior to
1609 		 * having configured keys.
1610 		 */
1611 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1612 			     ieee80211_is_robust_mgmt_frame(
1613 				     (struct ieee80211_hdr *) rx->skb->data)))
1614 			return -EACCES;
1615 	}
1616 
1617 	return 0;
1618 }
1619 
1620 static int
1621 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1622 {
1623 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1624 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1625 	bool check_port_control = false;
1626 	struct ethhdr *ehdr;
1627 	int ret;
1628 
1629 	*port_control = false;
1630 	if (ieee80211_has_a4(hdr->frame_control) &&
1631 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1632 		return -1;
1633 
1634 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1635 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1636 
1637 		if (!sdata->u.mgd.use_4addr)
1638 			return -1;
1639 		else
1640 			check_port_control = true;
1641 	}
1642 
1643 	if (is_multicast_ether_addr(hdr->addr1) &&
1644 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1645 		return -1;
1646 
1647 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1648 	if (ret < 0)
1649 		return ret;
1650 
1651 	ehdr = (struct ethhdr *) rx->skb->data;
1652 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1653 		*port_control = true;
1654 	else if (check_port_control)
1655 		return -1;
1656 
1657 	return 0;
1658 }
1659 
1660 /*
1661  * requires that rx->skb is a frame with ethernet header
1662  */
1663 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1664 {
1665 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1666 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1667 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1668 
1669 	/*
1670 	 * Allow EAPOL frames to us/the PAE group address regardless
1671 	 * of whether the frame was encrypted or not.
1672 	 */
1673 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1674 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1675 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1676 		return true;
1677 
1678 	if (ieee80211_802_1x_port_control(rx) ||
1679 	    ieee80211_drop_unencrypted(rx, fc))
1680 		return false;
1681 
1682 	return true;
1683 }
1684 
1685 /*
1686  * requires that rx->skb is a frame with ethernet header
1687  */
1688 static void
1689 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1690 {
1691 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1692 	struct net_device *dev = sdata->dev;
1693 	struct sk_buff *skb, *xmit_skb;
1694 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1695 	struct sta_info *dsta;
1696 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1697 
1698 	skb = rx->skb;
1699 	xmit_skb = NULL;
1700 
1701 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1702 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1703 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1704 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1705 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1706 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1707 			/*
1708 			 * send multicast frames both to higher layers in
1709 			 * local net stack and back to the wireless medium
1710 			 */
1711 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1712 			if (!xmit_skb)
1713 				net_info_ratelimited("%s: failed to clone multicast frame\n",
1714 						    dev->name);
1715 		} else {
1716 			dsta = sta_info_get(sdata, skb->data);
1717 			if (dsta) {
1718 				/*
1719 				 * The destination station is associated to
1720 				 * this AP (in this VLAN), so send the frame
1721 				 * directly to it and do not pass it to local
1722 				 * net stack.
1723 				 */
1724 				xmit_skb = skb;
1725 				skb = NULL;
1726 			}
1727 		}
1728 	}
1729 
1730 	if (skb) {
1731 		int align __maybe_unused;
1732 
1733 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1734 		/*
1735 		 * 'align' will only take the values 0 or 2 here
1736 		 * since all frames are required to be aligned
1737 		 * to 2-byte boundaries when being passed to
1738 		 * mac80211. That also explains the __skb_push()
1739 		 * below.
1740 		 */
1741 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1742 		if (align) {
1743 			if (WARN_ON(skb_headroom(skb) < 3)) {
1744 				dev_kfree_skb(skb);
1745 				skb = NULL;
1746 			} else {
1747 				u8 *data = skb->data;
1748 				size_t len = skb_headlen(skb);
1749 				skb->data -= align;
1750 				memmove(skb->data, data, len);
1751 				skb_set_tail_pointer(skb, len);
1752 			}
1753 		}
1754 #endif
1755 
1756 		if (skb) {
1757 			/* deliver to local stack */
1758 			skb->protocol = eth_type_trans(skb, dev);
1759 			memset(skb->cb, 0, sizeof(skb->cb));
1760 			netif_receive_skb(skb);
1761 		}
1762 	}
1763 
1764 	if (xmit_skb) {
1765 		/*
1766 		 * Send to wireless media and increase priority by 256 to
1767 		 * keep the received priority instead of reclassifying
1768 		 * the frame (see cfg80211_classify8021d).
1769 		 */
1770 		xmit_skb->priority += 256;
1771 		xmit_skb->protocol = htons(ETH_P_802_3);
1772 		skb_reset_network_header(xmit_skb);
1773 		skb_reset_mac_header(xmit_skb);
1774 		dev_queue_xmit(xmit_skb);
1775 	}
1776 }
1777 
1778 static ieee80211_rx_result debug_noinline
1779 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1780 {
1781 	struct net_device *dev = rx->sdata->dev;
1782 	struct sk_buff *skb = rx->skb;
1783 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1784 	__le16 fc = hdr->frame_control;
1785 	struct sk_buff_head frame_list;
1786 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1787 
1788 	if (unlikely(!ieee80211_is_data(fc)))
1789 		return RX_CONTINUE;
1790 
1791 	if (unlikely(!ieee80211_is_data_present(fc)))
1792 		return RX_DROP_MONITOR;
1793 
1794 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1795 		return RX_CONTINUE;
1796 
1797 	if (ieee80211_has_a4(hdr->frame_control) &&
1798 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1799 	    !rx->sdata->u.vlan.sta)
1800 		return RX_DROP_UNUSABLE;
1801 
1802 	if (is_multicast_ether_addr(hdr->addr1) &&
1803 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1804 	      rx->sdata->u.vlan.sta) ||
1805 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1806 	      rx->sdata->u.mgd.use_4addr)))
1807 		return RX_DROP_UNUSABLE;
1808 
1809 	skb->dev = dev;
1810 	__skb_queue_head_init(&frame_list);
1811 
1812 	if (skb_linearize(skb))
1813 		return RX_DROP_UNUSABLE;
1814 
1815 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1816 				 rx->sdata->vif.type,
1817 				 rx->local->hw.extra_tx_headroom, true);
1818 
1819 	while (!skb_queue_empty(&frame_list)) {
1820 		rx->skb = __skb_dequeue(&frame_list);
1821 
1822 		if (!ieee80211_frame_allowed(rx, fc)) {
1823 			dev_kfree_skb(rx->skb);
1824 			continue;
1825 		}
1826 		dev->stats.rx_packets++;
1827 		dev->stats.rx_bytes += rx->skb->len;
1828 
1829 		ieee80211_deliver_skb(rx);
1830 	}
1831 
1832 	return RX_QUEUED;
1833 }
1834 
1835 #ifdef CONFIG_MAC80211_MESH
1836 static ieee80211_rx_result
1837 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1838 {
1839 	struct ieee80211_hdr *fwd_hdr, *hdr;
1840 	struct ieee80211_tx_info *info;
1841 	struct ieee80211s_hdr *mesh_hdr;
1842 	struct sk_buff *skb = rx->skb, *fwd_skb;
1843 	struct ieee80211_local *local = rx->local;
1844 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1845 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1846 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1847 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1848 	u16 q, hdrlen;
1849 
1850 	hdr = (struct ieee80211_hdr *) skb->data;
1851 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1852 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1853 
1854 	/* frame is in RMC, don't forward */
1855 	if (ieee80211_is_data(hdr->frame_control) &&
1856 	    is_multicast_ether_addr(hdr->addr1) &&
1857 	    mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1858 		return RX_DROP_MONITOR;
1859 
1860 	if (!ieee80211_is_data(hdr->frame_control))
1861 		return RX_CONTINUE;
1862 
1863 	if (!mesh_hdr->ttl)
1864 		return RX_DROP_MONITOR;
1865 
1866 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
1867 		struct mesh_path *mppath;
1868 		char *proxied_addr;
1869 		char *mpp_addr;
1870 
1871 		if (is_multicast_ether_addr(hdr->addr1)) {
1872 			mpp_addr = hdr->addr3;
1873 			proxied_addr = mesh_hdr->eaddr1;
1874 		} else {
1875 			mpp_addr = hdr->addr4;
1876 			proxied_addr = mesh_hdr->eaddr2;
1877 		}
1878 
1879 		rcu_read_lock();
1880 		mppath = mpp_path_lookup(proxied_addr, sdata);
1881 		if (!mppath) {
1882 			mpp_path_add(proxied_addr, mpp_addr, sdata);
1883 		} else {
1884 			spin_lock_bh(&mppath->state_lock);
1885 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
1886 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1887 			spin_unlock_bh(&mppath->state_lock);
1888 		}
1889 		rcu_read_unlock();
1890 	}
1891 
1892 	/* Frame has reached destination.  Don't forward */
1893 	if (!is_multicast_ether_addr(hdr->addr1) &&
1894 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
1895 		return RX_CONTINUE;
1896 
1897 	q = ieee80211_select_queue_80211(sdata, skb, hdr);
1898 	if (ieee80211_queue_stopped(&local->hw, q)) {
1899 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1900 		return RX_DROP_MONITOR;
1901 	}
1902 	skb_set_queue_mapping(skb, q);
1903 
1904 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1905 		goto out;
1906 
1907 	if (!--mesh_hdr->ttl) {
1908 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1909 		return RX_DROP_MONITOR;
1910 	}
1911 
1912 	if (!ifmsh->mshcfg.dot11MeshForwarding)
1913 		goto out;
1914 
1915 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
1916 	if (!fwd_skb) {
1917 		net_info_ratelimited("%s: failed to clone mesh frame\n",
1918 				    sdata->name);
1919 		goto out;
1920 	}
1921 
1922 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1923 	info = IEEE80211_SKB_CB(fwd_skb);
1924 	memset(info, 0, sizeof(*info));
1925 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1926 	info->control.vif = &rx->sdata->vif;
1927 	info->control.jiffies = jiffies;
1928 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1929 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1930 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1931 	} else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1932 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1933 	} else {
1934 		/* unable to resolve next hop */
1935 		mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
1936 				    0, reason, fwd_hdr->addr2, sdata);
1937 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
1938 		kfree_skb(fwd_skb);
1939 		return RX_DROP_MONITOR;
1940 	}
1941 
1942 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
1943 	ieee80211_add_pending_skb(local, fwd_skb);
1944  out:
1945 	if (is_multicast_ether_addr(hdr->addr1) ||
1946 	    sdata->dev->flags & IFF_PROMISC)
1947 		return RX_CONTINUE;
1948 	else
1949 		return RX_DROP_MONITOR;
1950 }
1951 #endif
1952 
1953 static ieee80211_rx_result debug_noinline
1954 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1955 {
1956 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1957 	struct ieee80211_local *local = rx->local;
1958 	struct net_device *dev = sdata->dev;
1959 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1960 	__le16 fc = hdr->frame_control;
1961 	bool port_control;
1962 	int err;
1963 
1964 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1965 		return RX_CONTINUE;
1966 
1967 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1968 		return RX_DROP_MONITOR;
1969 
1970 	/*
1971 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
1972 	 * also drop the frame to cooked monitor interfaces.
1973 	 */
1974 	if (ieee80211_has_a4(hdr->frame_control) &&
1975 	    sdata->vif.type == NL80211_IFTYPE_AP) {
1976 		if (rx->sta &&
1977 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
1978 			cfg80211_rx_unexpected_4addr_frame(
1979 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
1980 		return RX_DROP_MONITOR;
1981 	}
1982 
1983 	err = __ieee80211_data_to_8023(rx, &port_control);
1984 	if (unlikely(err))
1985 		return RX_DROP_UNUSABLE;
1986 
1987 	if (!ieee80211_frame_allowed(rx, fc))
1988 		return RX_DROP_MONITOR;
1989 
1990 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1991 	    unlikely(port_control) && sdata->bss) {
1992 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1993 				     u.ap);
1994 		dev = sdata->dev;
1995 		rx->sdata = sdata;
1996 	}
1997 
1998 	rx->skb->dev = dev;
1999 
2000 	dev->stats.rx_packets++;
2001 	dev->stats.rx_bytes += rx->skb->len;
2002 
2003 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2004 	    !is_multicast_ether_addr(
2005 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2006 	    (!local->scanning &&
2007 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2008 			mod_timer(&local->dynamic_ps_timer, jiffies +
2009 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2010 	}
2011 
2012 	ieee80211_deliver_skb(rx);
2013 
2014 	return RX_QUEUED;
2015 }
2016 
2017 static ieee80211_rx_result debug_noinline
2018 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2019 {
2020 	struct sk_buff *skb = rx->skb;
2021 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2022 	struct tid_ampdu_rx *tid_agg_rx;
2023 	u16 start_seq_num;
2024 	u16 tid;
2025 
2026 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2027 		return RX_CONTINUE;
2028 
2029 	if (ieee80211_is_back_req(bar->frame_control)) {
2030 		struct {
2031 			__le16 control, start_seq_num;
2032 		} __packed bar_data;
2033 
2034 		if (!rx->sta)
2035 			return RX_DROP_MONITOR;
2036 
2037 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2038 				  &bar_data, sizeof(bar_data)))
2039 			return RX_DROP_MONITOR;
2040 
2041 		tid = le16_to_cpu(bar_data.control) >> 12;
2042 
2043 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2044 		if (!tid_agg_rx)
2045 			return RX_DROP_MONITOR;
2046 
2047 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2048 
2049 		/* reset session timer */
2050 		if (tid_agg_rx->timeout)
2051 			mod_timer(&tid_agg_rx->session_timer,
2052 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2053 
2054 		spin_lock(&tid_agg_rx->reorder_lock);
2055 		/* release stored frames up to start of BAR */
2056 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2057 						 start_seq_num);
2058 		spin_unlock(&tid_agg_rx->reorder_lock);
2059 
2060 		kfree_skb(skb);
2061 		return RX_QUEUED;
2062 	}
2063 
2064 	/*
2065 	 * After this point, we only want management frames,
2066 	 * so we can drop all remaining control frames to
2067 	 * cooked monitor interfaces.
2068 	 */
2069 	return RX_DROP_MONITOR;
2070 }
2071 
2072 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2073 					   struct ieee80211_mgmt *mgmt,
2074 					   size_t len)
2075 {
2076 	struct ieee80211_local *local = sdata->local;
2077 	struct sk_buff *skb;
2078 	struct ieee80211_mgmt *resp;
2079 
2080 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2081 		/* Not to own unicast address */
2082 		return;
2083 	}
2084 
2085 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2086 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2087 		/* Not from the current AP or not associated yet. */
2088 		return;
2089 	}
2090 
2091 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2092 		/* Too short SA Query request frame */
2093 		return;
2094 	}
2095 
2096 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2097 	if (skb == NULL)
2098 		return;
2099 
2100 	skb_reserve(skb, local->hw.extra_tx_headroom);
2101 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2102 	memset(resp, 0, 24);
2103 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2104 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2105 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2106 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2107 					  IEEE80211_STYPE_ACTION);
2108 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2109 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2110 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2111 	memcpy(resp->u.action.u.sa_query.trans_id,
2112 	       mgmt->u.action.u.sa_query.trans_id,
2113 	       WLAN_SA_QUERY_TR_ID_LEN);
2114 
2115 	ieee80211_tx_skb(sdata, skb);
2116 }
2117 
2118 static ieee80211_rx_result debug_noinline
2119 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2120 {
2121 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2122 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2123 
2124 	/*
2125 	 * From here on, look only at management frames.
2126 	 * Data and control frames are already handled,
2127 	 * and unknown (reserved) frames are useless.
2128 	 */
2129 	if (rx->skb->len < 24)
2130 		return RX_DROP_MONITOR;
2131 
2132 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2133 		return RX_DROP_MONITOR;
2134 
2135 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2136 	    ieee80211_is_beacon(mgmt->frame_control) &&
2137 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2138 		int sig = 0;
2139 
2140 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2141 			sig = status->signal;
2142 
2143 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2144 					    rx->skb->data, rx->skb->len,
2145 					    status->freq, sig, GFP_ATOMIC);
2146 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2147 	}
2148 
2149 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2150 		return RX_DROP_MONITOR;
2151 
2152 	if (ieee80211_drop_unencrypted_mgmt(rx))
2153 		return RX_DROP_UNUSABLE;
2154 
2155 	return RX_CONTINUE;
2156 }
2157 
2158 static ieee80211_rx_result debug_noinline
2159 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2160 {
2161 	struct ieee80211_local *local = rx->local;
2162 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2163 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2164 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2165 	int len = rx->skb->len;
2166 
2167 	if (!ieee80211_is_action(mgmt->frame_control))
2168 		return RX_CONTINUE;
2169 
2170 	/* drop too small frames */
2171 	if (len < IEEE80211_MIN_ACTION_SIZE)
2172 		return RX_DROP_UNUSABLE;
2173 
2174 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2175 		return RX_DROP_UNUSABLE;
2176 
2177 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2178 		return RX_DROP_UNUSABLE;
2179 
2180 	switch (mgmt->u.action.category) {
2181 	case WLAN_CATEGORY_HT:
2182 		/* reject HT action frames from stations not supporting HT */
2183 		if (!rx->sta->sta.ht_cap.ht_supported)
2184 			goto invalid;
2185 
2186 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2187 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2188 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2189 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2190 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2191 			break;
2192 
2193 		/* verify action & smps_control are present */
2194 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2195 			goto invalid;
2196 
2197 		switch (mgmt->u.action.u.ht_smps.action) {
2198 		case WLAN_HT_ACTION_SMPS: {
2199 			struct ieee80211_supported_band *sband;
2200 			u8 smps;
2201 
2202 			/* convert to HT capability */
2203 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2204 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2205 				smps = WLAN_HT_CAP_SM_PS_DISABLED;
2206 				break;
2207 			case WLAN_HT_SMPS_CONTROL_STATIC:
2208 				smps = WLAN_HT_CAP_SM_PS_STATIC;
2209 				break;
2210 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2211 				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2212 				break;
2213 			default:
2214 				goto invalid;
2215 			}
2216 			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2217 
2218 			/* if no change do nothing */
2219 			if ((rx->sta->sta.ht_cap.cap &
2220 					IEEE80211_HT_CAP_SM_PS) == smps)
2221 				goto handled;
2222 
2223 			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2224 			rx->sta->sta.ht_cap.cap |= smps;
2225 
2226 			sband = rx->local->hw.wiphy->bands[status->band];
2227 
2228 			rate_control_rate_update(local, sband, rx->sta,
2229 						 IEEE80211_RC_SMPS_CHANGED);
2230 			goto handled;
2231 		}
2232 		default:
2233 			goto invalid;
2234 		}
2235 
2236 		break;
2237 	case WLAN_CATEGORY_BACK:
2238 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2239 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2240 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2241 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2242 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2243 			break;
2244 
2245 		/* verify action_code is present */
2246 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2247 			break;
2248 
2249 		switch (mgmt->u.action.u.addba_req.action_code) {
2250 		case WLAN_ACTION_ADDBA_REQ:
2251 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2252 				   sizeof(mgmt->u.action.u.addba_req)))
2253 				goto invalid;
2254 			break;
2255 		case WLAN_ACTION_ADDBA_RESP:
2256 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2257 				   sizeof(mgmt->u.action.u.addba_resp)))
2258 				goto invalid;
2259 			break;
2260 		case WLAN_ACTION_DELBA:
2261 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2262 				   sizeof(mgmt->u.action.u.delba)))
2263 				goto invalid;
2264 			break;
2265 		default:
2266 			goto invalid;
2267 		}
2268 
2269 		goto queue;
2270 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2271 		if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2272 			break;
2273 
2274 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2275 			break;
2276 
2277 		/* verify action_code is present */
2278 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2279 			break;
2280 
2281 		switch (mgmt->u.action.u.measurement.action_code) {
2282 		case WLAN_ACTION_SPCT_MSR_REQ:
2283 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2284 				   sizeof(mgmt->u.action.u.measurement)))
2285 				break;
2286 			ieee80211_process_measurement_req(sdata, mgmt, len);
2287 			goto handled;
2288 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2289 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2290 				   sizeof(mgmt->u.action.u.chan_switch)))
2291 				break;
2292 
2293 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2294 				break;
2295 
2296 			if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2297 				break;
2298 
2299 			goto queue;
2300 		}
2301 		break;
2302 	case WLAN_CATEGORY_SA_QUERY:
2303 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2304 			   sizeof(mgmt->u.action.u.sa_query)))
2305 			break;
2306 
2307 		switch (mgmt->u.action.u.sa_query.action) {
2308 		case WLAN_ACTION_SA_QUERY_REQUEST:
2309 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2310 				break;
2311 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2312 			goto handled;
2313 		}
2314 		break;
2315 	case WLAN_CATEGORY_SELF_PROTECTED:
2316 		switch (mgmt->u.action.u.self_prot.action_code) {
2317 		case WLAN_SP_MESH_PEERING_OPEN:
2318 		case WLAN_SP_MESH_PEERING_CLOSE:
2319 		case WLAN_SP_MESH_PEERING_CONFIRM:
2320 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2321 				goto invalid;
2322 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2323 				/* userspace handles this frame */
2324 				break;
2325 			goto queue;
2326 		case WLAN_SP_MGK_INFORM:
2327 		case WLAN_SP_MGK_ACK:
2328 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2329 				goto invalid;
2330 			break;
2331 		}
2332 		break;
2333 	case WLAN_CATEGORY_MESH_ACTION:
2334 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2335 			break;
2336 		if (mesh_action_is_path_sel(mgmt) &&
2337 		  (!mesh_path_sel_is_hwmp(sdata)))
2338 			break;
2339 		goto queue;
2340 	}
2341 
2342 	return RX_CONTINUE;
2343 
2344  invalid:
2345 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2346 	/* will return in the next handlers */
2347 	return RX_CONTINUE;
2348 
2349  handled:
2350 	if (rx->sta)
2351 		rx->sta->rx_packets++;
2352 	dev_kfree_skb(rx->skb);
2353 	return RX_QUEUED;
2354 
2355  queue:
2356 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2357 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2358 	ieee80211_queue_work(&local->hw, &sdata->work);
2359 	if (rx->sta)
2360 		rx->sta->rx_packets++;
2361 	return RX_QUEUED;
2362 }
2363 
2364 static ieee80211_rx_result debug_noinline
2365 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2366 {
2367 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2368 	int sig = 0;
2369 
2370 	/* skip known-bad action frames and return them in the next handler */
2371 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2372 		return RX_CONTINUE;
2373 
2374 	/*
2375 	 * Getting here means the kernel doesn't know how to handle
2376 	 * it, but maybe userspace does ... include returned frames
2377 	 * so userspace can register for those to know whether ones
2378 	 * it transmitted were processed or returned.
2379 	 */
2380 
2381 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2382 		sig = status->signal;
2383 
2384 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2385 			     rx->skb->data, rx->skb->len,
2386 			     GFP_ATOMIC)) {
2387 		if (rx->sta)
2388 			rx->sta->rx_packets++;
2389 		dev_kfree_skb(rx->skb);
2390 		return RX_QUEUED;
2391 	}
2392 
2393 
2394 	return RX_CONTINUE;
2395 }
2396 
2397 static ieee80211_rx_result debug_noinline
2398 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2399 {
2400 	struct ieee80211_local *local = rx->local;
2401 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2402 	struct sk_buff *nskb;
2403 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2404 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2405 
2406 	if (!ieee80211_is_action(mgmt->frame_control))
2407 		return RX_CONTINUE;
2408 
2409 	/*
2410 	 * For AP mode, hostapd is responsible for handling any action
2411 	 * frames that we didn't handle, including returning unknown
2412 	 * ones. For all other modes we will return them to the sender,
2413 	 * setting the 0x80 bit in the action category, as required by
2414 	 * 802.11-2012 9.24.4.
2415 	 * Newer versions of hostapd shall also use the management frame
2416 	 * registration mechanisms, but older ones still use cooked
2417 	 * monitor interfaces so push all frames there.
2418 	 */
2419 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2420 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2421 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2422 		return RX_DROP_MONITOR;
2423 
2424 	if (is_multicast_ether_addr(mgmt->da))
2425 		return RX_DROP_MONITOR;
2426 
2427 	/* do not return rejected action frames */
2428 	if (mgmt->u.action.category & 0x80)
2429 		return RX_DROP_UNUSABLE;
2430 
2431 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2432 			       GFP_ATOMIC);
2433 	if (nskb) {
2434 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2435 
2436 		nmgmt->u.action.category |= 0x80;
2437 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2438 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2439 
2440 		memset(nskb->cb, 0, sizeof(nskb->cb));
2441 
2442 		ieee80211_tx_skb(rx->sdata, nskb);
2443 	}
2444 	dev_kfree_skb(rx->skb);
2445 	return RX_QUEUED;
2446 }
2447 
2448 static ieee80211_rx_result debug_noinline
2449 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2450 {
2451 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2452 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2453 	__le16 stype;
2454 
2455 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2456 
2457 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2458 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2459 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2460 		return RX_DROP_MONITOR;
2461 
2462 	switch (stype) {
2463 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2464 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2465 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2466 		/* process for all: mesh, mlme, ibss */
2467 		break;
2468 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2469 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2470 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2471 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2472 		if (is_multicast_ether_addr(mgmt->da) &&
2473 		    !is_broadcast_ether_addr(mgmt->da))
2474 			return RX_DROP_MONITOR;
2475 
2476 		/* process only for station */
2477 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2478 			return RX_DROP_MONITOR;
2479 		break;
2480 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2481 		/* process only for ibss */
2482 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2483 			return RX_DROP_MONITOR;
2484 		break;
2485 	default:
2486 		return RX_DROP_MONITOR;
2487 	}
2488 
2489 	/* queue up frame and kick off work to process it */
2490 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2491 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2492 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2493 	if (rx->sta)
2494 		rx->sta->rx_packets++;
2495 
2496 	return RX_QUEUED;
2497 }
2498 
2499 /* TODO: use IEEE80211_RX_FRAGMENTED */
2500 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2501 					struct ieee80211_rate *rate)
2502 {
2503 	struct ieee80211_sub_if_data *sdata;
2504 	struct ieee80211_local *local = rx->local;
2505 	struct sk_buff *skb = rx->skb, *skb2;
2506 	struct net_device *prev_dev = NULL;
2507 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2508 	int needed_headroom;
2509 
2510 	/*
2511 	 * If cooked monitor has been processed already, then
2512 	 * don't do it again. If not, set the flag.
2513 	 */
2514 	if (rx->flags & IEEE80211_RX_CMNTR)
2515 		goto out_free_skb;
2516 	rx->flags |= IEEE80211_RX_CMNTR;
2517 
2518 	/* If there are no cooked monitor interfaces, just free the SKB */
2519 	if (!local->cooked_mntrs)
2520 		goto out_free_skb;
2521 
2522 	/* room for the radiotap header based on driver features */
2523 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
2524 
2525 	if (skb_headroom(skb) < needed_headroom &&
2526 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2527 		goto out_free_skb;
2528 
2529 	/* prepend radiotap information */
2530 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2531 					 false);
2532 
2533 	skb_set_mac_header(skb, 0);
2534 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2535 	skb->pkt_type = PACKET_OTHERHOST;
2536 	skb->protocol = htons(ETH_P_802_2);
2537 
2538 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2539 		if (!ieee80211_sdata_running(sdata))
2540 			continue;
2541 
2542 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2543 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2544 			continue;
2545 
2546 		if (prev_dev) {
2547 			skb2 = skb_clone(skb, GFP_ATOMIC);
2548 			if (skb2) {
2549 				skb2->dev = prev_dev;
2550 				netif_receive_skb(skb2);
2551 			}
2552 		}
2553 
2554 		prev_dev = sdata->dev;
2555 		sdata->dev->stats.rx_packets++;
2556 		sdata->dev->stats.rx_bytes += skb->len;
2557 	}
2558 
2559 	if (prev_dev) {
2560 		skb->dev = prev_dev;
2561 		netif_receive_skb(skb);
2562 		return;
2563 	}
2564 
2565  out_free_skb:
2566 	dev_kfree_skb(skb);
2567 }
2568 
2569 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2570 					 ieee80211_rx_result res)
2571 {
2572 	switch (res) {
2573 	case RX_DROP_MONITOR:
2574 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2575 		if (rx->sta)
2576 			rx->sta->rx_dropped++;
2577 		/* fall through */
2578 	case RX_CONTINUE: {
2579 		struct ieee80211_rate *rate = NULL;
2580 		struct ieee80211_supported_band *sband;
2581 		struct ieee80211_rx_status *status;
2582 
2583 		status = IEEE80211_SKB_RXCB((rx->skb));
2584 
2585 		sband = rx->local->hw.wiphy->bands[status->band];
2586 		if (!(status->flag & RX_FLAG_HT))
2587 			rate = &sband->bitrates[status->rate_idx];
2588 
2589 		ieee80211_rx_cooked_monitor(rx, rate);
2590 		break;
2591 		}
2592 	case RX_DROP_UNUSABLE:
2593 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2594 		if (rx->sta)
2595 			rx->sta->rx_dropped++;
2596 		dev_kfree_skb(rx->skb);
2597 		break;
2598 	case RX_QUEUED:
2599 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2600 		break;
2601 	}
2602 }
2603 
2604 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2605 {
2606 	ieee80211_rx_result res = RX_DROP_MONITOR;
2607 	struct sk_buff *skb;
2608 
2609 #define CALL_RXH(rxh)			\
2610 	do {				\
2611 		res = rxh(rx);		\
2612 		if (res != RX_CONTINUE)	\
2613 			goto rxh_next;  \
2614 	} while (0);
2615 
2616 	spin_lock(&rx->local->rx_skb_queue.lock);
2617 	if (rx->local->running_rx_handler)
2618 		goto unlock;
2619 
2620 	rx->local->running_rx_handler = true;
2621 
2622 	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2623 		spin_unlock(&rx->local->rx_skb_queue.lock);
2624 
2625 		/*
2626 		 * all the other fields are valid across frames
2627 		 * that belong to an aMPDU since they are on the
2628 		 * same TID from the same station
2629 		 */
2630 		rx->skb = skb;
2631 
2632 		CALL_RXH(ieee80211_rx_h_decrypt)
2633 		CALL_RXH(ieee80211_rx_h_check_more_data)
2634 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2635 		CALL_RXH(ieee80211_rx_h_sta_process)
2636 		CALL_RXH(ieee80211_rx_h_defragment)
2637 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2638 		/* must be after MMIC verify so header is counted in MPDU mic */
2639 #ifdef CONFIG_MAC80211_MESH
2640 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2641 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2642 #endif
2643 		CALL_RXH(ieee80211_rx_h_amsdu)
2644 		CALL_RXH(ieee80211_rx_h_data)
2645 		CALL_RXH(ieee80211_rx_h_ctrl);
2646 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2647 		CALL_RXH(ieee80211_rx_h_action)
2648 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2649 		CALL_RXH(ieee80211_rx_h_action_return)
2650 		CALL_RXH(ieee80211_rx_h_mgmt)
2651 
2652  rxh_next:
2653 		ieee80211_rx_handlers_result(rx, res);
2654 		spin_lock(&rx->local->rx_skb_queue.lock);
2655 #undef CALL_RXH
2656 	}
2657 
2658 	rx->local->running_rx_handler = false;
2659 
2660  unlock:
2661 	spin_unlock(&rx->local->rx_skb_queue.lock);
2662 }
2663 
2664 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2665 {
2666 	ieee80211_rx_result res = RX_DROP_MONITOR;
2667 
2668 #define CALL_RXH(rxh)			\
2669 	do {				\
2670 		res = rxh(rx);		\
2671 		if (res != RX_CONTINUE)	\
2672 			goto rxh_next;  \
2673 	} while (0);
2674 
2675 	CALL_RXH(ieee80211_rx_h_check)
2676 
2677 	ieee80211_rx_reorder_ampdu(rx);
2678 
2679 	ieee80211_rx_handlers(rx);
2680 	return;
2681 
2682  rxh_next:
2683 	ieee80211_rx_handlers_result(rx, res);
2684 
2685 #undef CALL_RXH
2686 }
2687 
2688 /*
2689  * This function makes calls into the RX path, therefore
2690  * it has to be invoked under RCU read lock.
2691  */
2692 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2693 {
2694 	struct ieee80211_rx_data rx = {
2695 		.sta = sta,
2696 		.sdata = sta->sdata,
2697 		.local = sta->local,
2698 		/* This is OK -- must be QoS data frame */
2699 		.security_idx = tid,
2700 		.seqno_idx = tid,
2701 		.flags = 0,
2702 	};
2703 	struct tid_ampdu_rx *tid_agg_rx;
2704 
2705 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2706 	if (!tid_agg_rx)
2707 		return;
2708 
2709 	spin_lock(&tid_agg_rx->reorder_lock);
2710 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx);
2711 	spin_unlock(&tid_agg_rx->reorder_lock);
2712 
2713 	ieee80211_rx_handlers(&rx);
2714 }
2715 
2716 /* main receive path */
2717 
2718 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2719 				struct ieee80211_hdr *hdr)
2720 {
2721 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2722 	struct sk_buff *skb = rx->skb;
2723 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2724 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2725 	int multicast = is_multicast_ether_addr(hdr->addr1);
2726 
2727 	switch (sdata->vif.type) {
2728 	case NL80211_IFTYPE_STATION:
2729 		if (!bssid && !sdata->u.mgd.use_4addr)
2730 			return 0;
2731 		if (!multicast &&
2732 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2733 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2734 			    sdata->u.mgd.use_4addr)
2735 				return 0;
2736 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2737 		}
2738 		break;
2739 	case NL80211_IFTYPE_ADHOC:
2740 		if (!bssid)
2741 			return 0;
2742 		if (ieee80211_is_beacon(hdr->frame_control)) {
2743 			return 1;
2744 		} else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2745 			return 0;
2746 		} else if (!multicast &&
2747 			   !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2748 			if (!(sdata->dev->flags & IFF_PROMISC))
2749 				return 0;
2750 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2751 		} else if (!rx->sta) {
2752 			int rate_idx;
2753 			if (status->flag & RX_FLAG_HT)
2754 				rate_idx = 0; /* TODO: HT rates */
2755 			else
2756 				rate_idx = status->rate_idx;
2757 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2758 						 BIT(rate_idx));
2759 		}
2760 		break;
2761 	case NL80211_IFTYPE_MESH_POINT:
2762 		if (!multicast &&
2763 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2764 			if (!(sdata->dev->flags & IFF_PROMISC))
2765 				return 0;
2766 
2767 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2768 		}
2769 		break;
2770 	case NL80211_IFTYPE_AP_VLAN:
2771 	case NL80211_IFTYPE_AP:
2772 		if (!bssid) {
2773 			if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2774 				return 0;
2775 		} else if (!ieee80211_bssid_match(bssid,
2776 					sdata->vif.addr)) {
2777 			/*
2778 			 * Accept public action frames even when the
2779 			 * BSSID doesn't match, this is used for P2P
2780 			 * and location updates. Note that mac80211
2781 			 * itself never looks at these frames.
2782 			 */
2783 			if (ieee80211_is_public_action(hdr, skb->len))
2784 				return 1;
2785 			if (!ieee80211_is_beacon(hdr->frame_control))
2786 				return 0;
2787 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2788 		}
2789 		break;
2790 	case NL80211_IFTYPE_WDS:
2791 		if (bssid || !ieee80211_is_data(hdr->frame_control))
2792 			return 0;
2793 		if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
2794 			return 0;
2795 		break;
2796 	default:
2797 		/* should never get here */
2798 		WARN_ON(1);
2799 		break;
2800 	}
2801 
2802 	return 1;
2803 }
2804 
2805 /*
2806  * This function returns whether or not the SKB
2807  * was destined for RX processing or not, which,
2808  * if consume is true, is equivalent to whether
2809  * or not the skb was consumed.
2810  */
2811 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2812 					    struct sk_buff *skb, bool consume)
2813 {
2814 	struct ieee80211_local *local = rx->local;
2815 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2816 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2817 	struct ieee80211_hdr *hdr = (void *)skb->data;
2818 	int prepares;
2819 
2820 	rx->skb = skb;
2821 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
2822 	prepares = prepare_for_handlers(rx, hdr);
2823 
2824 	if (!prepares)
2825 		return false;
2826 
2827 	if (!consume) {
2828 		skb = skb_copy(skb, GFP_ATOMIC);
2829 		if (!skb) {
2830 			if (net_ratelimit())
2831 				wiphy_debug(local->hw.wiphy,
2832 					"failed to copy skb for %s\n",
2833 					sdata->name);
2834 			return true;
2835 		}
2836 
2837 		rx->skb = skb;
2838 	}
2839 
2840 	ieee80211_invoke_rx_handlers(rx);
2841 	return true;
2842 }
2843 
2844 /*
2845  * This is the actual Rx frames handler. as it blongs to Rx path it must
2846  * be called with rcu_read_lock protection.
2847  */
2848 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2849 					 struct sk_buff *skb)
2850 {
2851 	struct ieee80211_local *local = hw_to_local(hw);
2852 	struct ieee80211_sub_if_data *sdata;
2853 	struct ieee80211_hdr *hdr;
2854 	__le16 fc;
2855 	struct ieee80211_rx_data rx;
2856 	struct ieee80211_sub_if_data *prev;
2857 	struct sta_info *sta, *tmp, *prev_sta;
2858 	int err = 0;
2859 
2860 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2861 	memset(&rx, 0, sizeof(rx));
2862 	rx.skb = skb;
2863 	rx.local = local;
2864 
2865 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2866 		local->dot11ReceivedFragmentCount++;
2867 
2868 	if (ieee80211_is_mgmt(fc))
2869 		err = skb_linearize(skb);
2870 	else
2871 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2872 
2873 	if (err) {
2874 		dev_kfree_skb(skb);
2875 		return;
2876 	}
2877 
2878 	hdr = (struct ieee80211_hdr *)skb->data;
2879 	ieee80211_parse_qos(&rx);
2880 	ieee80211_verify_alignment(&rx);
2881 
2882 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
2883 		     ieee80211_is_beacon(hdr->frame_control)))
2884 		ieee80211_scan_rx(local, skb);
2885 
2886 	if (ieee80211_is_data(fc)) {
2887 		prev_sta = NULL;
2888 
2889 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
2890 			if (!prev_sta) {
2891 				prev_sta = sta;
2892 				continue;
2893 			}
2894 
2895 			rx.sta = prev_sta;
2896 			rx.sdata = prev_sta->sdata;
2897 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
2898 
2899 			prev_sta = sta;
2900 		}
2901 
2902 		if (prev_sta) {
2903 			rx.sta = prev_sta;
2904 			rx.sdata = prev_sta->sdata;
2905 
2906 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2907 				return;
2908 			goto out;
2909 		}
2910 	}
2911 
2912 	prev = NULL;
2913 
2914 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2915 		if (!ieee80211_sdata_running(sdata))
2916 			continue;
2917 
2918 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2919 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2920 			continue;
2921 
2922 		/*
2923 		 * frame is destined for this interface, but if it's
2924 		 * not also for the previous one we handle that after
2925 		 * the loop to avoid copying the SKB once too much
2926 		 */
2927 
2928 		if (!prev) {
2929 			prev = sdata;
2930 			continue;
2931 		}
2932 
2933 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2934 		rx.sdata = prev;
2935 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
2936 
2937 		prev = sdata;
2938 	}
2939 
2940 	if (prev) {
2941 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2942 		rx.sdata = prev;
2943 
2944 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2945 			return;
2946 	}
2947 
2948  out:
2949 	dev_kfree_skb(skb);
2950 }
2951 
2952 /*
2953  * This is the receive path handler. It is called by a low level driver when an
2954  * 802.11 MPDU is received from the hardware.
2955  */
2956 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2957 {
2958 	struct ieee80211_local *local = hw_to_local(hw);
2959 	struct ieee80211_rate *rate = NULL;
2960 	struct ieee80211_supported_band *sband;
2961 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2962 
2963 	WARN_ON_ONCE(softirq_count() == 0);
2964 
2965 	if (WARN_ON(status->band < 0 ||
2966 		    status->band >= IEEE80211_NUM_BANDS))
2967 		goto drop;
2968 
2969 	sband = local->hw.wiphy->bands[status->band];
2970 	if (WARN_ON(!sband))
2971 		goto drop;
2972 
2973 	/*
2974 	 * If we're suspending, it is possible although not too likely
2975 	 * that we'd be receiving frames after having already partially
2976 	 * quiesced the stack. We can't process such frames then since
2977 	 * that might, for example, cause stations to be added or other
2978 	 * driver callbacks be invoked.
2979 	 */
2980 	if (unlikely(local->quiescing || local->suspended))
2981 		goto drop;
2982 
2983 	/* We might be during a HW reconfig, prevent Rx for the same reason */
2984 	if (unlikely(local->in_reconfig))
2985 		goto drop;
2986 
2987 	/*
2988 	 * The same happens when we're not even started,
2989 	 * but that's worth a warning.
2990 	 */
2991 	if (WARN_ON(!local->started))
2992 		goto drop;
2993 
2994 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2995 		/*
2996 		 * Validate the rate, unless a PLCP error means that
2997 		 * we probably can't have a valid rate here anyway.
2998 		 */
2999 
3000 		if (status->flag & RX_FLAG_HT) {
3001 			/*
3002 			 * rate_idx is MCS index, which can be [0-76]
3003 			 * as documented on:
3004 			 *
3005 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3006 			 *
3007 			 * Anything else would be some sort of driver or
3008 			 * hardware error. The driver should catch hardware
3009 			 * errors.
3010 			 */
3011 			if (WARN((status->rate_idx < 0 ||
3012 				 status->rate_idx > 76),
3013 				 "Rate marked as an HT rate but passed "
3014 				 "status->rate_idx is not "
3015 				 "an MCS index [0-76]: %d (0x%02x)\n",
3016 				 status->rate_idx,
3017 				 status->rate_idx))
3018 				goto drop;
3019 		} else {
3020 			if (WARN_ON(status->rate_idx < 0 ||
3021 				    status->rate_idx >= sband->n_bitrates))
3022 				goto drop;
3023 			rate = &sband->bitrates[status->rate_idx];
3024 		}
3025 	}
3026 
3027 	status->rx_flags = 0;
3028 
3029 	/*
3030 	 * key references and virtual interfaces are protected using RCU
3031 	 * and this requires that we are in a read-side RCU section during
3032 	 * receive processing
3033 	 */
3034 	rcu_read_lock();
3035 
3036 	/*
3037 	 * Frames with failed FCS/PLCP checksum are not returned,
3038 	 * all other frames are returned without radiotap header
3039 	 * if it was previously present.
3040 	 * Also, frames with less than 16 bytes are dropped.
3041 	 */
3042 	skb = ieee80211_rx_monitor(local, skb, rate);
3043 	if (!skb) {
3044 		rcu_read_unlock();
3045 		return;
3046 	}
3047 
3048 	ieee80211_tpt_led_trig_rx(local,
3049 			((struct ieee80211_hdr *)skb->data)->frame_control,
3050 			skb->len);
3051 	__ieee80211_rx_handle_packet(hw, skb);
3052 
3053 	rcu_read_unlock();
3054 
3055 	return;
3056  drop:
3057 	kfree_skb(skb);
3058 }
3059 EXPORT_SYMBOL(ieee80211_rx);
3060 
3061 /* This is a version of the rx handler that can be called from hard irq
3062  * context. Post the skb on the queue and schedule the tasklet */
3063 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3064 {
3065 	struct ieee80211_local *local = hw_to_local(hw);
3066 
3067 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3068 
3069 	skb->pkt_type = IEEE80211_RX_MSG;
3070 	skb_queue_tail(&local->skb_queue, skb);
3071 	tasklet_schedule(&local->tasklet);
3072 }
3073 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3074