xref: /openbmc/linux/net/mac80211/rx.c (revision 05bcf503)
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 |
64 			    RX_FLAG_FAILED_PLCP_CRC |
65 			    RX_FLAG_AMPDU_IS_ZEROLEN))
66 		return 1;
67 	if (unlikely(skb->len < 16 + present_fcs_len))
68 		return 1;
69 	if (ieee80211_is_ctl(hdr->frame_control) &&
70 	    !ieee80211_is_pspoll(hdr->frame_control) &&
71 	    !ieee80211_is_back_req(hdr->frame_control))
72 		return 1;
73 	return 0;
74 }
75 
76 static int
77 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
78 			  struct ieee80211_rx_status *status)
79 {
80 	int len;
81 
82 	/* always present fields */
83 	len = sizeof(struct ieee80211_radiotap_header) + 9;
84 
85 	if (status->flag & RX_FLAG_MACTIME_MPDU)
86 		len += 8;
87 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
88 		len += 1;
89 
90 	if (len & 1) /* padding for RX_FLAGS if necessary */
91 		len++;
92 
93 	if (status->flag & RX_FLAG_HT) /* HT info */
94 		len += 3;
95 
96 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
97 		/* padding */
98 		while (len & 3)
99 			len++;
100 		len += 8;
101 	}
102 
103 	return len;
104 }
105 
106 /*
107  * ieee80211_add_rx_radiotap_header - add radiotap header
108  *
109  * add a radiotap header containing all the fields which the hardware provided.
110  */
111 static void
112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
113 				 struct sk_buff *skb,
114 				 struct ieee80211_rate *rate,
115 				 int rtap_len, bool has_fcs)
116 {
117 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
118 	struct ieee80211_radiotap_header *rthdr;
119 	unsigned char *pos;
120 	u16 rx_flags = 0;
121 
122 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
123 	memset(rthdr, 0, rtap_len);
124 
125 	/* radiotap header, set always present flags */
126 	rthdr->it_present =
127 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
128 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
129 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
130 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
131 	rthdr->it_len = cpu_to_le16(rtap_len);
132 
133 	pos = (unsigned char *)(rthdr+1);
134 
135 	/* the order of the following fields is important */
136 
137 	/* IEEE80211_RADIOTAP_TSFT */
138 	if (status->flag & RX_FLAG_MACTIME_MPDU) {
139 		put_unaligned_le64(status->mactime, pos);
140 		rthdr->it_present |=
141 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
142 		pos += 8;
143 	}
144 
145 	/* IEEE80211_RADIOTAP_FLAGS */
146 	if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
147 		*pos |= IEEE80211_RADIOTAP_F_FCS;
148 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
149 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
150 	if (status->flag & RX_FLAG_SHORTPRE)
151 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
152 	pos++;
153 
154 	/* IEEE80211_RADIOTAP_RATE */
155 	if (!rate || status->flag & RX_FLAG_HT) {
156 		/*
157 		 * Without rate information don't add it. If we have,
158 		 * MCS information is a separate field in radiotap,
159 		 * added below. The byte here is needed as padding
160 		 * for the channel though, so initialise it to 0.
161 		 */
162 		*pos = 0;
163 	} else {
164 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
165 		*pos = rate->bitrate / 5;
166 	}
167 	pos++;
168 
169 	/* IEEE80211_RADIOTAP_CHANNEL */
170 	put_unaligned_le16(status->freq, pos);
171 	pos += 2;
172 	if (status->band == IEEE80211_BAND_5GHZ)
173 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
174 				   pos);
175 	else if (status->flag & RX_FLAG_HT)
176 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
177 				   pos);
178 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
179 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
180 				   pos);
181 	else if (rate)
182 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
183 				   pos);
184 	else
185 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
186 	pos += 2;
187 
188 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
189 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
190 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
191 		*pos = status->signal;
192 		rthdr->it_present |=
193 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
194 		pos++;
195 	}
196 
197 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
198 
199 	/* IEEE80211_RADIOTAP_ANTENNA */
200 	*pos = status->antenna;
201 	pos++;
202 
203 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
204 
205 	/* IEEE80211_RADIOTAP_RX_FLAGS */
206 	/* ensure 2 byte alignment for the 2 byte field as required */
207 	if ((pos - (u8 *)rthdr) & 1)
208 		pos++;
209 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
210 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
211 	put_unaligned_le16(rx_flags, pos);
212 	pos += 2;
213 
214 	if (status->flag & RX_FLAG_HT) {
215 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
216 		*pos++ = local->hw.radiotap_mcs_details;
217 		*pos = 0;
218 		if (status->flag & RX_FLAG_SHORT_GI)
219 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
220 		if (status->flag & RX_FLAG_40MHZ)
221 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
222 		if (status->flag & RX_FLAG_HT_GF)
223 			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
224 		pos++;
225 		*pos++ = status->rate_idx;
226 	}
227 
228 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
229 		u16 flags = 0;
230 
231 		/* ensure 4 byte alignment */
232 		while ((pos - (u8 *)rthdr) & 3)
233 			pos++;
234 		rthdr->it_present |=
235 			cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
236 		put_unaligned_le32(status->ampdu_reference, pos);
237 		pos += 4;
238 		if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
239 			flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
240 		if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
241 			flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
242 		if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
243 			flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
244 		if (status->flag & RX_FLAG_AMPDU_IS_LAST)
245 			flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
246 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
247 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
248 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
249 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
250 		put_unaligned_le16(flags, pos);
251 		pos += 2;
252 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
253 			*pos++ = status->ampdu_delimiter_crc;
254 		else
255 			*pos++ = 0;
256 		*pos++ = 0;
257 	}
258 }
259 
260 /*
261  * This function copies a received frame to all monitor interfaces and
262  * returns a cleaned-up SKB that no longer includes the FCS nor the
263  * radiotap header the driver might have added.
264  */
265 static struct sk_buff *
266 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
267 		     struct ieee80211_rate *rate)
268 {
269 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
270 	struct ieee80211_sub_if_data *sdata;
271 	int needed_headroom;
272 	struct sk_buff *skb, *skb2;
273 	struct net_device *prev_dev = NULL;
274 	int present_fcs_len = 0;
275 
276 	/*
277 	 * First, we may need to make a copy of the skb because
278 	 *  (1) we need to modify it for radiotap (if not present), and
279 	 *  (2) the other RX handlers will modify the skb we got.
280 	 *
281 	 * We don't need to, of course, if we aren't going to return
282 	 * the SKB because it has a bad FCS/PLCP checksum.
283 	 */
284 
285 	/* room for the radiotap header based on driver features */
286 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
287 
288 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
289 		present_fcs_len = FCS_LEN;
290 
291 	/* make sure hdr->frame_control is on the linear part */
292 	if (!pskb_may_pull(origskb, 2)) {
293 		dev_kfree_skb(origskb);
294 		return NULL;
295 	}
296 
297 	if (!local->monitors) {
298 		if (should_drop_frame(origskb, present_fcs_len)) {
299 			dev_kfree_skb(origskb);
300 			return NULL;
301 		}
302 
303 		return remove_monitor_info(local, origskb);
304 	}
305 
306 	if (should_drop_frame(origskb, present_fcs_len)) {
307 		/* only need to expand headroom if necessary */
308 		skb = origskb;
309 		origskb = NULL;
310 
311 		/*
312 		 * This shouldn't trigger often because most devices have an
313 		 * RX header they pull before we get here, and that should
314 		 * be big enough for our radiotap information. We should
315 		 * probably export the length to drivers so that we can have
316 		 * them allocate enough headroom to start with.
317 		 */
318 		if (skb_headroom(skb) < needed_headroom &&
319 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
320 			dev_kfree_skb(skb);
321 			return NULL;
322 		}
323 	} else {
324 		/*
325 		 * Need to make a copy and possibly remove radiotap header
326 		 * and FCS from the original.
327 		 */
328 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
329 
330 		origskb = remove_monitor_info(local, origskb);
331 
332 		if (!skb)
333 			return origskb;
334 	}
335 
336 	/* prepend radiotap information */
337 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
338 					 true);
339 
340 	skb_reset_mac_header(skb);
341 	skb->ip_summed = CHECKSUM_UNNECESSARY;
342 	skb->pkt_type = PACKET_OTHERHOST;
343 	skb->protocol = htons(ETH_P_802_2);
344 
345 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
346 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
347 			continue;
348 
349 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
350 			continue;
351 
352 		if (!ieee80211_sdata_running(sdata))
353 			continue;
354 
355 		if (prev_dev) {
356 			skb2 = skb_clone(skb, GFP_ATOMIC);
357 			if (skb2) {
358 				skb2->dev = prev_dev;
359 				netif_receive_skb(skb2);
360 			}
361 		}
362 
363 		prev_dev = sdata->dev;
364 		sdata->dev->stats.rx_packets++;
365 		sdata->dev->stats.rx_bytes += skb->len;
366 	}
367 
368 	if (prev_dev) {
369 		skb->dev = prev_dev;
370 		netif_receive_skb(skb);
371 	} else
372 		dev_kfree_skb(skb);
373 
374 	return origskb;
375 }
376 
377 
378 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
379 {
380 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
381 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
382 	int tid, seqno_idx, security_idx;
383 
384 	/* does the frame have a qos control field? */
385 	if (ieee80211_is_data_qos(hdr->frame_control)) {
386 		u8 *qc = ieee80211_get_qos_ctl(hdr);
387 		/* frame has qos control */
388 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
389 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
390 			status->rx_flags |= IEEE80211_RX_AMSDU;
391 
392 		seqno_idx = tid;
393 		security_idx = tid;
394 	} else {
395 		/*
396 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
397 		 *
398 		 *	Sequence numbers for management frames, QoS data
399 		 *	frames with a broadcast/multicast address in the
400 		 *	Address 1 field, and all non-QoS data frames sent
401 		 *	by QoS STAs are assigned using an additional single
402 		 *	modulo-4096 counter, [...]
403 		 *
404 		 * We also use that counter for non-QoS STAs.
405 		 */
406 		seqno_idx = NUM_RX_DATA_QUEUES;
407 		security_idx = 0;
408 		if (ieee80211_is_mgmt(hdr->frame_control))
409 			security_idx = NUM_RX_DATA_QUEUES;
410 		tid = 0;
411 	}
412 
413 	rx->seqno_idx = seqno_idx;
414 	rx->security_idx = security_idx;
415 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
416 	 * For now, set skb->priority to 0 for other cases. */
417 	rx->skb->priority = (tid > 7) ? 0 : tid;
418 }
419 
420 /**
421  * DOC: Packet alignment
422  *
423  * Drivers always need to pass packets that are aligned to two-byte boundaries
424  * to the stack.
425  *
426  * Additionally, should, if possible, align the payload data in a way that
427  * guarantees that the contained IP header is aligned to a four-byte
428  * boundary. In the case of regular frames, this simply means aligning the
429  * payload to a four-byte boundary (because either the IP header is directly
430  * contained, or IV/RFC1042 headers that have a length divisible by four are
431  * in front of it).  If the payload data is not properly aligned and the
432  * architecture doesn't support efficient unaligned operations, mac80211
433  * will align the data.
434  *
435  * With A-MSDU frames, however, the payload data address must yield two modulo
436  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
437  * push the IP header further back to a multiple of four again. Thankfully, the
438  * specs were sane enough this time around to require padding each A-MSDU
439  * subframe to a length that is a multiple of four.
440  *
441  * Padding like Atheros hardware adds which is between the 802.11 header and
442  * the payload is not supported, the driver is required to move the 802.11
443  * header to be directly in front of the payload in that case.
444  */
445 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
446 {
447 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
448 	WARN_ONCE((unsigned long)rx->skb->data & 1,
449 		  "unaligned packet at 0x%p\n", rx->skb->data);
450 #endif
451 }
452 
453 
454 /* rx handlers */
455 
456 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
457 {
458 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
459 
460 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
461 		return 0;
462 
463 	return ieee80211_is_robust_mgmt_frame(hdr);
464 }
465 
466 
467 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
468 {
469 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
470 
471 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
472 		return 0;
473 
474 	return ieee80211_is_robust_mgmt_frame(hdr);
475 }
476 
477 
478 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
479 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
480 {
481 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
482 	struct ieee80211_mmie *mmie;
483 
484 	if (skb->len < 24 + sizeof(*mmie) ||
485 	    !is_multicast_ether_addr(hdr->da))
486 		return -1;
487 
488 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
489 		return -1; /* not a robust management frame */
490 
491 	mmie = (struct ieee80211_mmie *)
492 		(skb->data + skb->len - sizeof(*mmie));
493 	if (mmie->element_id != WLAN_EID_MMIE ||
494 	    mmie->length != sizeof(*mmie) - 2)
495 		return -1;
496 
497 	return le16_to_cpu(mmie->key_id);
498 }
499 
500 
501 static ieee80211_rx_result
502 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
503 {
504 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
505 	char *dev_addr = rx->sdata->vif.addr;
506 
507 	if (ieee80211_is_data(hdr->frame_control)) {
508 		if (is_multicast_ether_addr(hdr->addr1)) {
509 			if (ieee80211_has_tods(hdr->frame_control) ||
510 				!ieee80211_has_fromds(hdr->frame_control))
511 				return RX_DROP_MONITOR;
512 			if (ether_addr_equal(hdr->addr3, dev_addr))
513 				return RX_DROP_MONITOR;
514 		} else {
515 			if (!ieee80211_has_a4(hdr->frame_control))
516 				return RX_DROP_MONITOR;
517 			if (ether_addr_equal(hdr->addr4, dev_addr))
518 				return RX_DROP_MONITOR;
519 		}
520 	}
521 
522 	/* If there is not an established peer link and this is not a peer link
523 	 * establisment frame, beacon or probe, drop the frame.
524 	 */
525 
526 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
527 		struct ieee80211_mgmt *mgmt;
528 
529 		if (!ieee80211_is_mgmt(hdr->frame_control))
530 			return RX_DROP_MONITOR;
531 
532 		if (ieee80211_is_action(hdr->frame_control)) {
533 			u8 category;
534 
535 			/* make sure category field is present */
536 			if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
537 				return RX_DROP_MONITOR;
538 
539 			mgmt = (struct ieee80211_mgmt *)hdr;
540 			category = mgmt->u.action.category;
541 			if (category != WLAN_CATEGORY_MESH_ACTION &&
542 				category != WLAN_CATEGORY_SELF_PROTECTED)
543 				return RX_DROP_MONITOR;
544 			return RX_CONTINUE;
545 		}
546 
547 		if (ieee80211_is_probe_req(hdr->frame_control) ||
548 		    ieee80211_is_probe_resp(hdr->frame_control) ||
549 		    ieee80211_is_beacon(hdr->frame_control) ||
550 		    ieee80211_is_auth(hdr->frame_control))
551 			return RX_CONTINUE;
552 
553 		return RX_DROP_MONITOR;
554 
555 	}
556 
557 	return RX_CONTINUE;
558 }
559 
560 #define SEQ_MODULO 0x1000
561 #define SEQ_MASK   0xfff
562 
563 static inline int seq_less(u16 sq1, u16 sq2)
564 {
565 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
566 }
567 
568 static inline u16 seq_inc(u16 sq)
569 {
570 	return (sq + 1) & SEQ_MASK;
571 }
572 
573 static inline u16 seq_sub(u16 sq1, u16 sq2)
574 {
575 	return (sq1 - sq2) & SEQ_MASK;
576 }
577 
578 
579 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
580 					    struct tid_ampdu_rx *tid_agg_rx,
581 					    int index)
582 {
583 	struct ieee80211_local *local = sdata->local;
584 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
585 	struct ieee80211_rx_status *status;
586 
587 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
588 
589 	if (!skb)
590 		goto no_frame;
591 
592 	/* release the frame from the reorder ring buffer */
593 	tid_agg_rx->stored_mpdu_num--;
594 	tid_agg_rx->reorder_buf[index] = NULL;
595 	status = IEEE80211_SKB_RXCB(skb);
596 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
597 	skb_queue_tail(&local->rx_skb_queue, skb);
598 
599 no_frame:
600 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
601 }
602 
603 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
604 					     struct tid_ampdu_rx *tid_agg_rx,
605 					     u16 head_seq_num)
606 {
607 	int index;
608 
609 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
610 
611 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
612 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
613 							tid_agg_rx->buf_size;
614 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
615 	}
616 }
617 
618 /*
619  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
620  * the skb was added to the buffer longer than this time ago, the earlier
621  * frames that have not yet been received are assumed to be lost and the skb
622  * can be released for processing. This may also release other skb's from the
623  * reorder buffer if there are no additional gaps between the frames.
624  *
625  * Callers must hold tid_agg_rx->reorder_lock.
626  */
627 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
628 
629 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
630 					  struct tid_ampdu_rx *tid_agg_rx)
631 {
632 	int index, j;
633 
634 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
635 
636 	/* release the buffer until next missing frame */
637 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
638 						tid_agg_rx->buf_size;
639 	if (!tid_agg_rx->reorder_buf[index] &&
640 	    tid_agg_rx->stored_mpdu_num) {
641 		/*
642 		 * No buffers ready to be released, but check whether any
643 		 * frames in the reorder buffer have timed out.
644 		 */
645 		int skipped = 1;
646 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
647 		     j = (j + 1) % tid_agg_rx->buf_size) {
648 			if (!tid_agg_rx->reorder_buf[j]) {
649 				skipped++;
650 				continue;
651 			}
652 			if (skipped &&
653 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
654 					HT_RX_REORDER_BUF_TIMEOUT))
655 				goto set_release_timer;
656 
657 			ht_dbg_ratelimited(sdata,
658 					   "release an RX reorder frame due to timeout on earlier frames\n");
659 			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j);
660 
661 			/*
662 			 * Increment the head seq# also for the skipped slots.
663 			 */
664 			tid_agg_rx->head_seq_num =
665 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
666 			skipped = 0;
667 		}
668 	} else while (tid_agg_rx->reorder_buf[index]) {
669 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
670 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
671 							tid_agg_rx->buf_size;
672 	}
673 
674 	if (tid_agg_rx->stored_mpdu_num) {
675 		j = index = seq_sub(tid_agg_rx->head_seq_num,
676 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
677 
678 		for (; j != (index - 1) % tid_agg_rx->buf_size;
679 		     j = (j + 1) % tid_agg_rx->buf_size) {
680 			if (tid_agg_rx->reorder_buf[j])
681 				break;
682 		}
683 
684  set_release_timer:
685 
686 		mod_timer(&tid_agg_rx->reorder_timer,
687 			  tid_agg_rx->reorder_time[j] + 1 +
688 			  HT_RX_REORDER_BUF_TIMEOUT);
689 	} else {
690 		del_timer(&tid_agg_rx->reorder_timer);
691 	}
692 }
693 
694 /*
695  * As this function belongs to the RX path it must be under
696  * rcu_read_lock protection. It returns false if the frame
697  * can be processed immediately, true if it was consumed.
698  */
699 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
700 					     struct tid_ampdu_rx *tid_agg_rx,
701 					     struct sk_buff *skb)
702 {
703 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
704 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
705 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
706 	u16 head_seq_num, buf_size;
707 	int index;
708 	bool ret = true;
709 
710 	spin_lock(&tid_agg_rx->reorder_lock);
711 
712 	buf_size = tid_agg_rx->buf_size;
713 	head_seq_num = tid_agg_rx->head_seq_num;
714 
715 	/* frame with out of date sequence number */
716 	if (seq_less(mpdu_seq_num, head_seq_num)) {
717 		dev_kfree_skb(skb);
718 		goto out;
719 	}
720 
721 	/*
722 	 * If frame the sequence number exceeds our buffering window
723 	 * size release some previous frames to make room for this one.
724 	 */
725 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
726 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
727 		/* release stored frames up to new head to stack */
728 		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
729 						 head_seq_num);
730 	}
731 
732 	/* Now the new frame is always in the range of the reordering buffer */
733 
734 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
735 
736 	/* check if we already stored this frame */
737 	if (tid_agg_rx->reorder_buf[index]) {
738 		dev_kfree_skb(skb);
739 		goto out;
740 	}
741 
742 	/*
743 	 * If the current MPDU is in the right order and nothing else
744 	 * is stored we can process it directly, no need to buffer it.
745 	 * If it is first but there's something stored, we may be able
746 	 * to release frames after this one.
747 	 */
748 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
749 	    tid_agg_rx->stored_mpdu_num == 0) {
750 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
751 		ret = false;
752 		goto out;
753 	}
754 
755 	/* put the frame in the reordering buffer */
756 	tid_agg_rx->reorder_buf[index] = skb;
757 	tid_agg_rx->reorder_time[index] = jiffies;
758 	tid_agg_rx->stored_mpdu_num++;
759 	ieee80211_sta_reorder_release(sdata, tid_agg_rx);
760 
761  out:
762 	spin_unlock(&tid_agg_rx->reorder_lock);
763 	return ret;
764 }
765 
766 /*
767  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
768  * true if the MPDU was buffered, false if it should be processed.
769  */
770 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
771 {
772 	struct sk_buff *skb = rx->skb;
773 	struct ieee80211_local *local = rx->local;
774 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
775 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
776 	struct sta_info *sta = rx->sta;
777 	struct tid_ampdu_rx *tid_agg_rx;
778 	u16 sc;
779 	u8 tid, ack_policy;
780 
781 	if (!ieee80211_is_data_qos(hdr->frame_control))
782 		goto dont_reorder;
783 
784 	/*
785 	 * filter the QoS data rx stream according to
786 	 * STA/TID and check if this STA/TID is on aggregation
787 	 */
788 
789 	if (!sta)
790 		goto dont_reorder;
791 
792 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
793 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
794 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
795 
796 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
797 	if (!tid_agg_rx)
798 		goto dont_reorder;
799 
800 	/* qos null data frames are excluded */
801 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
802 		goto dont_reorder;
803 
804 	/* not part of a BA session */
805 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
806 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
807 		goto dont_reorder;
808 
809 	/* not actually part of this BA session */
810 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
811 		goto dont_reorder;
812 
813 	/* new, potentially un-ordered, ampdu frame - process it */
814 
815 	/* reset session timer */
816 	if (tid_agg_rx->timeout)
817 		tid_agg_rx->last_rx = jiffies;
818 
819 	/* if this mpdu is fragmented - terminate rx aggregation session */
820 	sc = le16_to_cpu(hdr->seq_ctrl);
821 	if (sc & IEEE80211_SCTL_FRAG) {
822 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
823 		skb_queue_tail(&rx->sdata->skb_queue, skb);
824 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
825 		return;
826 	}
827 
828 	/*
829 	 * No locking needed -- we will only ever process one
830 	 * RX packet at a time, and thus own tid_agg_rx. All
831 	 * other code manipulating it needs to (and does) make
832 	 * sure that we cannot get to it any more before doing
833 	 * anything with it.
834 	 */
835 	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb))
836 		return;
837 
838  dont_reorder:
839 	skb_queue_tail(&local->rx_skb_queue, skb);
840 }
841 
842 static ieee80211_rx_result debug_noinline
843 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
844 {
845 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
846 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
847 
848 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
849 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
850 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
851 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
852 			     hdr->seq_ctrl)) {
853 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
854 				rx->local->dot11FrameDuplicateCount++;
855 				rx->sta->num_duplicates++;
856 			}
857 			return RX_DROP_UNUSABLE;
858 		} else
859 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
860 	}
861 
862 	if (unlikely(rx->skb->len < 16)) {
863 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
864 		return RX_DROP_MONITOR;
865 	}
866 
867 	/* Drop disallowed frame classes based on STA auth/assoc state;
868 	 * IEEE 802.11, Chap 5.5.
869 	 *
870 	 * mac80211 filters only based on association state, i.e. it drops
871 	 * Class 3 frames from not associated stations. hostapd sends
872 	 * deauth/disassoc frames when needed. In addition, hostapd is
873 	 * responsible for filtering on both auth and assoc states.
874 	 */
875 
876 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
877 		return ieee80211_rx_mesh_check(rx);
878 
879 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
880 		      ieee80211_is_pspoll(hdr->frame_control)) &&
881 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
882 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
883 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
884 		/*
885 		 * accept port control frames from the AP even when it's not
886 		 * yet marked ASSOC to prevent a race where we don't set the
887 		 * assoc bit quickly enough before it sends the first frame
888 		 */
889 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
890 		    ieee80211_is_data_present(hdr->frame_control)) {
891 			unsigned int hdrlen;
892 			__be16 ethertype;
893 
894 			hdrlen = ieee80211_hdrlen(hdr->frame_control);
895 
896 			if (rx->skb->len < hdrlen + 8)
897 				return RX_DROP_MONITOR;
898 
899 			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
900 			if (ethertype == rx->sdata->control_port_protocol)
901 				return RX_CONTINUE;
902 		}
903 
904 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
905 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
906 					       hdr->addr2,
907 					       GFP_ATOMIC))
908 			return RX_DROP_UNUSABLE;
909 
910 		return RX_DROP_MONITOR;
911 	}
912 
913 	return RX_CONTINUE;
914 }
915 
916 
917 static ieee80211_rx_result debug_noinline
918 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
919 {
920 	struct sk_buff *skb = rx->skb;
921 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
922 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
923 	int keyidx;
924 	int hdrlen;
925 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
926 	struct ieee80211_key *sta_ptk = NULL;
927 	int mmie_keyidx = -1;
928 	__le16 fc;
929 
930 	/*
931 	 * Key selection 101
932 	 *
933 	 * There are four types of keys:
934 	 *  - GTK (group keys)
935 	 *  - IGTK (group keys for management frames)
936 	 *  - PTK (pairwise keys)
937 	 *  - STK (station-to-station pairwise keys)
938 	 *
939 	 * When selecting a key, we have to distinguish between multicast
940 	 * (including broadcast) and unicast frames, the latter can only
941 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
942 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
943 	 * unicast frames can also use key indices like GTKs. Hence, if we
944 	 * don't have a PTK/STK we check the key index for a WEP key.
945 	 *
946 	 * Note that in a regular BSS, multicast frames are sent by the
947 	 * AP only, associated stations unicast the frame to the AP first
948 	 * which then multicasts it on their behalf.
949 	 *
950 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
951 	 * with each station, that is something we don't currently handle.
952 	 * The spec seems to expect that one negotiates the same key with
953 	 * every station but there's no such requirement; VLANs could be
954 	 * possible.
955 	 */
956 
957 	/*
958 	 * No point in finding a key and decrypting if the frame is neither
959 	 * addressed to us nor a multicast frame.
960 	 */
961 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
962 		return RX_CONTINUE;
963 
964 	/* start without a key */
965 	rx->key = NULL;
966 
967 	if (rx->sta)
968 		sta_ptk = rcu_dereference(rx->sta->ptk);
969 
970 	fc = hdr->frame_control;
971 
972 	if (!ieee80211_has_protected(fc))
973 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
974 
975 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
976 		rx->key = sta_ptk;
977 		if ((status->flag & RX_FLAG_DECRYPTED) &&
978 		    (status->flag & RX_FLAG_IV_STRIPPED))
979 			return RX_CONTINUE;
980 		/* Skip decryption if the frame is not protected. */
981 		if (!ieee80211_has_protected(fc))
982 			return RX_CONTINUE;
983 	} else if (mmie_keyidx >= 0) {
984 		/* Broadcast/multicast robust management frame / BIP */
985 		if ((status->flag & RX_FLAG_DECRYPTED) &&
986 		    (status->flag & RX_FLAG_IV_STRIPPED))
987 			return RX_CONTINUE;
988 
989 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
990 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
991 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
992 		if (rx->sta)
993 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
994 		if (!rx->key)
995 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
996 	} else if (!ieee80211_has_protected(fc)) {
997 		/*
998 		 * The frame was not protected, so skip decryption. However, we
999 		 * need to set rx->key if there is a key that could have been
1000 		 * used so that the frame may be dropped if encryption would
1001 		 * have been expected.
1002 		 */
1003 		struct ieee80211_key *key = NULL;
1004 		struct ieee80211_sub_if_data *sdata = rx->sdata;
1005 		int i;
1006 
1007 		if (ieee80211_is_mgmt(fc) &&
1008 		    is_multicast_ether_addr(hdr->addr1) &&
1009 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1010 			rx->key = key;
1011 		else {
1012 			if (rx->sta) {
1013 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1014 					key = rcu_dereference(rx->sta->gtk[i]);
1015 					if (key)
1016 						break;
1017 				}
1018 			}
1019 			if (!key) {
1020 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1021 					key = rcu_dereference(sdata->keys[i]);
1022 					if (key)
1023 						break;
1024 				}
1025 			}
1026 			if (key)
1027 				rx->key = key;
1028 		}
1029 		return RX_CONTINUE;
1030 	} else {
1031 		u8 keyid;
1032 		/*
1033 		 * The device doesn't give us the IV so we won't be
1034 		 * able to look up the key. That's ok though, we
1035 		 * don't need to decrypt the frame, we just won't
1036 		 * be able to keep statistics accurate.
1037 		 * Except for key threshold notifications, should
1038 		 * we somehow allow the driver to tell us which key
1039 		 * the hardware used if this flag is set?
1040 		 */
1041 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1042 		    (status->flag & RX_FLAG_IV_STRIPPED))
1043 			return RX_CONTINUE;
1044 
1045 		hdrlen = ieee80211_hdrlen(fc);
1046 
1047 		if (rx->skb->len < 8 + hdrlen)
1048 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1049 
1050 		/*
1051 		 * no need to call ieee80211_wep_get_keyidx,
1052 		 * it verifies a bunch of things we've done already
1053 		 */
1054 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1055 		keyidx = keyid >> 6;
1056 
1057 		/* check per-station GTK first, if multicast packet */
1058 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1059 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1060 
1061 		/* if not found, try default key */
1062 		if (!rx->key) {
1063 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1064 
1065 			/*
1066 			 * RSNA-protected unicast frames should always be
1067 			 * sent with pairwise or station-to-station keys,
1068 			 * but for WEP we allow using a key index as well.
1069 			 */
1070 			if (rx->key &&
1071 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1072 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1073 			    !is_multicast_ether_addr(hdr->addr1))
1074 				rx->key = NULL;
1075 		}
1076 	}
1077 
1078 	if (rx->key) {
1079 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1080 			return RX_DROP_MONITOR;
1081 
1082 		rx->key->tx_rx_count++;
1083 		/* TODO: add threshold stuff again */
1084 	} else {
1085 		return RX_DROP_MONITOR;
1086 	}
1087 
1088 	switch (rx->key->conf.cipher) {
1089 	case WLAN_CIPHER_SUITE_WEP40:
1090 	case WLAN_CIPHER_SUITE_WEP104:
1091 		result = ieee80211_crypto_wep_decrypt(rx);
1092 		break;
1093 	case WLAN_CIPHER_SUITE_TKIP:
1094 		result = ieee80211_crypto_tkip_decrypt(rx);
1095 		break;
1096 	case WLAN_CIPHER_SUITE_CCMP:
1097 		result = ieee80211_crypto_ccmp_decrypt(rx);
1098 		break;
1099 	case WLAN_CIPHER_SUITE_AES_CMAC:
1100 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1101 		break;
1102 	default:
1103 		/*
1104 		 * We can reach here only with HW-only algorithms
1105 		 * but why didn't it decrypt the frame?!
1106 		 */
1107 		return RX_DROP_UNUSABLE;
1108 	}
1109 
1110 	/* the hdr variable is invalid after the decrypt handlers */
1111 
1112 	/* either the frame has been decrypted or will be dropped */
1113 	status->flag |= RX_FLAG_DECRYPTED;
1114 
1115 	return result;
1116 }
1117 
1118 static ieee80211_rx_result debug_noinline
1119 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1120 {
1121 	struct ieee80211_local *local;
1122 	struct ieee80211_hdr *hdr;
1123 	struct sk_buff *skb;
1124 
1125 	local = rx->local;
1126 	skb = rx->skb;
1127 	hdr = (struct ieee80211_hdr *) skb->data;
1128 
1129 	if (!local->pspolling)
1130 		return RX_CONTINUE;
1131 
1132 	if (!ieee80211_has_fromds(hdr->frame_control))
1133 		/* this is not from AP */
1134 		return RX_CONTINUE;
1135 
1136 	if (!ieee80211_is_data(hdr->frame_control))
1137 		return RX_CONTINUE;
1138 
1139 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1140 		/* AP has no more frames buffered for us */
1141 		local->pspolling = false;
1142 		return RX_CONTINUE;
1143 	}
1144 
1145 	/* more data bit is set, let's request a new frame from the AP */
1146 	ieee80211_send_pspoll(local, rx->sdata);
1147 
1148 	return RX_CONTINUE;
1149 }
1150 
1151 static void ap_sta_ps_start(struct sta_info *sta)
1152 {
1153 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1154 	struct ieee80211_local *local = sdata->local;
1155 
1156 	atomic_inc(&sdata->bss->num_sta_ps);
1157 	set_sta_flag(sta, WLAN_STA_PS_STA);
1158 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1159 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1160 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1161 	       sta->sta.addr, sta->sta.aid);
1162 }
1163 
1164 static void ap_sta_ps_end(struct sta_info *sta)
1165 {
1166 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1167 	       sta->sta.addr, sta->sta.aid);
1168 
1169 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1170 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1171 		       sta->sta.addr, sta->sta.aid);
1172 		return;
1173 	}
1174 
1175 	ieee80211_sta_ps_deliver_wakeup(sta);
1176 }
1177 
1178 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1179 {
1180 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1181 	bool in_ps;
1182 
1183 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1184 
1185 	/* Don't let the same PS state be set twice */
1186 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1187 	if ((start && in_ps) || (!start && !in_ps))
1188 		return -EINVAL;
1189 
1190 	if (start)
1191 		ap_sta_ps_start(sta_inf);
1192 	else
1193 		ap_sta_ps_end(sta_inf);
1194 
1195 	return 0;
1196 }
1197 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1198 
1199 static ieee80211_rx_result debug_noinline
1200 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1201 {
1202 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1203 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1204 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1205 	int tid, ac;
1206 
1207 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1208 		return RX_CONTINUE;
1209 
1210 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1211 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1212 		return RX_CONTINUE;
1213 
1214 	/*
1215 	 * The device handles station powersave, so don't do anything about
1216 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1217 	 * it to mac80211 since they're handled.)
1218 	 */
1219 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1220 		return RX_CONTINUE;
1221 
1222 	/*
1223 	 * Don't do anything if the station isn't already asleep. In
1224 	 * the uAPSD case, the station will probably be marked asleep,
1225 	 * in the PS-Poll case the station must be confused ...
1226 	 */
1227 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1228 		return RX_CONTINUE;
1229 
1230 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1231 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1232 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1233 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1234 			else
1235 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1236 		}
1237 
1238 		/* Free PS Poll skb here instead of returning RX_DROP that would
1239 		 * count as an dropped frame. */
1240 		dev_kfree_skb(rx->skb);
1241 
1242 		return RX_QUEUED;
1243 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1244 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1245 		   ieee80211_has_pm(hdr->frame_control) &&
1246 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1247 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1248 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1249 		ac = ieee802_1d_to_ac[tid & 7];
1250 
1251 		/*
1252 		 * If this AC is not trigger-enabled do nothing.
1253 		 *
1254 		 * NB: This could/should check a separate bitmap of trigger-
1255 		 * enabled queues, but for now we only implement uAPSD w/o
1256 		 * TSPEC changes to the ACs, so they're always the same.
1257 		 */
1258 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1259 			return RX_CONTINUE;
1260 
1261 		/* if we are in a service period, do nothing */
1262 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1263 			return RX_CONTINUE;
1264 
1265 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1266 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1267 		else
1268 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1269 	}
1270 
1271 	return RX_CONTINUE;
1272 }
1273 
1274 static ieee80211_rx_result debug_noinline
1275 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1276 {
1277 	struct sta_info *sta = rx->sta;
1278 	struct sk_buff *skb = rx->skb;
1279 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1280 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1281 
1282 	if (!sta)
1283 		return RX_CONTINUE;
1284 
1285 	/*
1286 	 * Update last_rx only for IBSS packets which are for the current
1287 	 * BSSID to avoid keeping the current IBSS network alive in cases
1288 	 * where other STAs start using different BSSID.
1289 	 */
1290 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1291 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1292 						NL80211_IFTYPE_ADHOC);
1293 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid)) {
1294 			sta->last_rx = jiffies;
1295 			if (ieee80211_is_data(hdr->frame_control)) {
1296 				sta->last_rx_rate_idx = status->rate_idx;
1297 				sta->last_rx_rate_flag = status->flag;
1298 			}
1299 		}
1300 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1301 		/*
1302 		 * Mesh beacons will update last_rx when if they are found to
1303 		 * match the current local configuration when processed.
1304 		 */
1305 		sta->last_rx = jiffies;
1306 		if (ieee80211_is_data(hdr->frame_control)) {
1307 			sta->last_rx_rate_idx = status->rate_idx;
1308 			sta->last_rx_rate_flag = status->flag;
1309 		}
1310 	}
1311 
1312 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1313 		return RX_CONTINUE;
1314 
1315 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1316 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1317 
1318 	sta->rx_fragments++;
1319 	sta->rx_bytes += rx->skb->len;
1320 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1321 		sta->last_signal = status->signal;
1322 		ewma_add(&sta->avg_signal, -status->signal);
1323 	}
1324 
1325 	/*
1326 	 * Change STA power saving mode only at the end of a frame
1327 	 * exchange sequence.
1328 	 */
1329 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1330 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1331 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1332 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1333 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1334 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1335 			/*
1336 			 * Ignore doze->wake transitions that are
1337 			 * indicated by non-data frames, the standard
1338 			 * is unclear here, but for example going to
1339 			 * PS mode and then scanning would cause a
1340 			 * doze->wake transition for the probe request,
1341 			 * and that is clearly undesirable.
1342 			 */
1343 			if (ieee80211_is_data(hdr->frame_control) &&
1344 			    !ieee80211_has_pm(hdr->frame_control))
1345 				ap_sta_ps_end(sta);
1346 		} else {
1347 			if (ieee80211_has_pm(hdr->frame_control))
1348 				ap_sta_ps_start(sta);
1349 		}
1350 	}
1351 
1352 	/*
1353 	 * Drop (qos-)data::nullfunc frames silently, since they
1354 	 * are used only to control station power saving mode.
1355 	 */
1356 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1357 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1358 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1359 
1360 		/*
1361 		 * If we receive a 4-addr nullfunc frame from a STA
1362 		 * that was not moved to a 4-addr STA vlan yet send
1363 		 * the event to userspace and for older hostapd drop
1364 		 * the frame to the monitor interface.
1365 		 */
1366 		if (ieee80211_has_a4(hdr->frame_control) &&
1367 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1368 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1369 		      !rx->sdata->u.vlan.sta))) {
1370 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1371 				cfg80211_rx_unexpected_4addr_frame(
1372 					rx->sdata->dev, sta->sta.addr,
1373 					GFP_ATOMIC);
1374 			return RX_DROP_MONITOR;
1375 		}
1376 		/*
1377 		 * Update counter and free packet here to avoid
1378 		 * counting this as a dropped packed.
1379 		 */
1380 		sta->rx_packets++;
1381 		dev_kfree_skb(rx->skb);
1382 		return RX_QUEUED;
1383 	}
1384 
1385 	return RX_CONTINUE;
1386 } /* ieee80211_rx_h_sta_process */
1387 
1388 static inline struct ieee80211_fragment_entry *
1389 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1390 			 unsigned int frag, unsigned int seq, int rx_queue,
1391 			 struct sk_buff **skb)
1392 {
1393 	struct ieee80211_fragment_entry *entry;
1394 	int idx;
1395 
1396 	idx = sdata->fragment_next;
1397 	entry = &sdata->fragments[sdata->fragment_next++];
1398 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1399 		sdata->fragment_next = 0;
1400 
1401 	if (!skb_queue_empty(&entry->skb_list))
1402 		__skb_queue_purge(&entry->skb_list);
1403 
1404 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1405 	*skb = NULL;
1406 	entry->first_frag_time = jiffies;
1407 	entry->seq = seq;
1408 	entry->rx_queue = rx_queue;
1409 	entry->last_frag = frag;
1410 	entry->ccmp = 0;
1411 	entry->extra_len = 0;
1412 
1413 	return entry;
1414 }
1415 
1416 static inline struct ieee80211_fragment_entry *
1417 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1418 			  unsigned int frag, unsigned int seq,
1419 			  int rx_queue, struct ieee80211_hdr *hdr)
1420 {
1421 	struct ieee80211_fragment_entry *entry;
1422 	int i, idx;
1423 
1424 	idx = sdata->fragment_next;
1425 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1426 		struct ieee80211_hdr *f_hdr;
1427 
1428 		idx--;
1429 		if (idx < 0)
1430 			idx = IEEE80211_FRAGMENT_MAX - 1;
1431 
1432 		entry = &sdata->fragments[idx];
1433 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1434 		    entry->rx_queue != rx_queue ||
1435 		    entry->last_frag + 1 != frag)
1436 			continue;
1437 
1438 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1439 
1440 		/*
1441 		 * Check ftype and addresses are equal, else check next fragment
1442 		 */
1443 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1444 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1445 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1446 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1447 			continue;
1448 
1449 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1450 			__skb_queue_purge(&entry->skb_list);
1451 			continue;
1452 		}
1453 		return entry;
1454 	}
1455 
1456 	return NULL;
1457 }
1458 
1459 static ieee80211_rx_result debug_noinline
1460 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1461 {
1462 	struct ieee80211_hdr *hdr;
1463 	u16 sc;
1464 	__le16 fc;
1465 	unsigned int frag, seq;
1466 	struct ieee80211_fragment_entry *entry;
1467 	struct sk_buff *skb;
1468 	struct ieee80211_rx_status *status;
1469 
1470 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1471 	fc = hdr->frame_control;
1472 
1473 	if (ieee80211_is_ctl(fc))
1474 		return RX_CONTINUE;
1475 
1476 	sc = le16_to_cpu(hdr->seq_ctrl);
1477 	frag = sc & IEEE80211_SCTL_FRAG;
1478 
1479 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1480 		   is_multicast_ether_addr(hdr->addr1))) {
1481 		/* not fragmented */
1482 		goto out;
1483 	}
1484 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1485 
1486 	if (skb_linearize(rx->skb))
1487 		return RX_DROP_UNUSABLE;
1488 
1489 	/*
1490 	 *  skb_linearize() might change the skb->data and
1491 	 *  previously cached variables (in this case, hdr) need to
1492 	 *  be refreshed with the new data.
1493 	 */
1494 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1495 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1496 
1497 	if (frag == 0) {
1498 		/* This is the first fragment of a new frame. */
1499 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1500 						 rx->seqno_idx, &(rx->skb));
1501 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1502 		    ieee80211_has_protected(fc)) {
1503 			int queue = rx->security_idx;
1504 			/* Store CCMP PN so that we can verify that the next
1505 			 * fragment has a sequential PN value. */
1506 			entry->ccmp = 1;
1507 			memcpy(entry->last_pn,
1508 			       rx->key->u.ccmp.rx_pn[queue],
1509 			       CCMP_PN_LEN);
1510 		}
1511 		return RX_QUEUED;
1512 	}
1513 
1514 	/* This is a fragment for a frame that should already be pending in
1515 	 * fragment cache. Add this fragment to the end of the pending entry.
1516 	 */
1517 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1518 					  rx->seqno_idx, hdr);
1519 	if (!entry) {
1520 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1521 		return RX_DROP_MONITOR;
1522 	}
1523 
1524 	/* Verify that MPDUs within one MSDU have sequential PN values.
1525 	 * (IEEE 802.11i, 8.3.3.4.5) */
1526 	if (entry->ccmp) {
1527 		int i;
1528 		u8 pn[CCMP_PN_LEN], *rpn;
1529 		int queue;
1530 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1531 			return RX_DROP_UNUSABLE;
1532 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1533 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1534 			pn[i]++;
1535 			if (pn[i])
1536 				break;
1537 		}
1538 		queue = rx->security_idx;
1539 		rpn = rx->key->u.ccmp.rx_pn[queue];
1540 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1541 			return RX_DROP_UNUSABLE;
1542 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1543 	}
1544 
1545 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1546 	__skb_queue_tail(&entry->skb_list, rx->skb);
1547 	entry->last_frag = frag;
1548 	entry->extra_len += rx->skb->len;
1549 	if (ieee80211_has_morefrags(fc)) {
1550 		rx->skb = NULL;
1551 		return RX_QUEUED;
1552 	}
1553 
1554 	rx->skb = __skb_dequeue(&entry->skb_list);
1555 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1556 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1557 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1558 					      GFP_ATOMIC))) {
1559 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1560 			__skb_queue_purge(&entry->skb_list);
1561 			return RX_DROP_UNUSABLE;
1562 		}
1563 	}
1564 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1565 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1566 		dev_kfree_skb(skb);
1567 	}
1568 
1569 	/* Complete frame has been reassembled - process it now */
1570 	status = IEEE80211_SKB_RXCB(rx->skb);
1571 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1572 
1573  out:
1574 	if (rx->sta)
1575 		rx->sta->rx_packets++;
1576 	if (is_multicast_ether_addr(hdr->addr1))
1577 		rx->local->dot11MulticastReceivedFrameCount++;
1578 	else
1579 		ieee80211_led_rx(rx->local);
1580 	return RX_CONTINUE;
1581 }
1582 
1583 static int
1584 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1585 {
1586 	if (unlikely(!rx->sta ||
1587 	    !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1588 		return -EACCES;
1589 
1590 	return 0;
1591 }
1592 
1593 static int
1594 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1595 {
1596 	struct sk_buff *skb = rx->skb;
1597 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1598 
1599 	/*
1600 	 * Pass through unencrypted frames if the hardware has
1601 	 * decrypted them already.
1602 	 */
1603 	if (status->flag & RX_FLAG_DECRYPTED)
1604 		return 0;
1605 
1606 	/* Drop unencrypted frames if key is set. */
1607 	if (unlikely(!ieee80211_has_protected(fc) &&
1608 		     !ieee80211_is_nullfunc(fc) &&
1609 		     ieee80211_is_data(fc) &&
1610 		     (rx->key || rx->sdata->drop_unencrypted)))
1611 		return -EACCES;
1612 
1613 	return 0;
1614 }
1615 
1616 static int
1617 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1618 {
1619 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1620 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1621 	__le16 fc = hdr->frame_control;
1622 
1623 	/*
1624 	 * Pass through unencrypted frames if the hardware has
1625 	 * decrypted them already.
1626 	 */
1627 	if (status->flag & RX_FLAG_DECRYPTED)
1628 		return 0;
1629 
1630 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1631 		if (unlikely(!ieee80211_has_protected(fc) &&
1632 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1633 			     rx->key)) {
1634 			if (ieee80211_is_deauth(fc))
1635 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1636 							    rx->skb->data,
1637 							    rx->skb->len);
1638 			else if (ieee80211_is_disassoc(fc))
1639 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1640 							      rx->skb->data,
1641 							      rx->skb->len);
1642 			return -EACCES;
1643 		}
1644 		/* BIP does not use Protected field, so need to check MMIE */
1645 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1646 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1647 			if (ieee80211_is_deauth(fc))
1648 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1649 							    rx->skb->data,
1650 							    rx->skb->len);
1651 			else if (ieee80211_is_disassoc(fc))
1652 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1653 							      rx->skb->data,
1654 							      rx->skb->len);
1655 			return -EACCES;
1656 		}
1657 		/*
1658 		 * When using MFP, Action frames are not allowed prior to
1659 		 * having configured keys.
1660 		 */
1661 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1662 			     ieee80211_is_robust_mgmt_frame(
1663 				     (struct ieee80211_hdr *) rx->skb->data)))
1664 			return -EACCES;
1665 	}
1666 
1667 	return 0;
1668 }
1669 
1670 static int
1671 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1672 {
1673 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1674 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1675 	bool check_port_control = false;
1676 	struct ethhdr *ehdr;
1677 	int ret;
1678 
1679 	*port_control = false;
1680 	if (ieee80211_has_a4(hdr->frame_control) &&
1681 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1682 		return -1;
1683 
1684 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1685 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1686 
1687 		if (!sdata->u.mgd.use_4addr)
1688 			return -1;
1689 		else
1690 			check_port_control = true;
1691 	}
1692 
1693 	if (is_multicast_ether_addr(hdr->addr1) &&
1694 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1695 		return -1;
1696 
1697 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1698 	if (ret < 0)
1699 		return ret;
1700 
1701 	ehdr = (struct ethhdr *) rx->skb->data;
1702 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1703 		*port_control = true;
1704 	else if (check_port_control)
1705 		return -1;
1706 
1707 	return 0;
1708 }
1709 
1710 /*
1711  * requires that rx->skb is a frame with ethernet header
1712  */
1713 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1714 {
1715 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1716 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1717 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1718 
1719 	/*
1720 	 * Allow EAPOL frames to us/the PAE group address regardless
1721 	 * of whether the frame was encrypted or not.
1722 	 */
1723 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1724 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1725 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1726 		return true;
1727 
1728 	if (ieee80211_802_1x_port_control(rx) ||
1729 	    ieee80211_drop_unencrypted(rx, fc))
1730 		return false;
1731 
1732 	return true;
1733 }
1734 
1735 /*
1736  * requires that rx->skb is a frame with ethernet header
1737  */
1738 static void
1739 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1740 {
1741 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1742 	struct net_device *dev = sdata->dev;
1743 	struct sk_buff *skb, *xmit_skb;
1744 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1745 	struct sta_info *dsta;
1746 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1747 
1748 	skb = rx->skb;
1749 	xmit_skb = NULL;
1750 
1751 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1752 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1753 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1754 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1755 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1756 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1757 			/*
1758 			 * send multicast frames both to higher layers in
1759 			 * local net stack and back to the wireless medium
1760 			 */
1761 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1762 			if (!xmit_skb)
1763 				net_info_ratelimited("%s: failed to clone multicast frame\n",
1764 						    dev->name);
1765 		} else {
1766 			dsta = sta_info_get(sdata, skb->data);
1767 			if (dsta) {
1768 				/*
1769 				 * The destination station is associated to
1770 				 * this AP (in this VLAN), so send the frame
1771 				 * directly to it and do not pass it to local
1772 				 * net stack.
1773 				 */
1774 				xmit_skb = skb;
1775 				skb = NULL;
1776 			}
1777 		}
1778 	}
1779 
1780 	if (skb) {
1781 		int align __maybe_unused;
1782 
1783 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1784 		/*
1785 		 * 'align' will only take the values 0 or 2 here
1786 		 * since all frames are required to be aligned
1787 		 * to 2-byte boundaries when being passed to
1788 		 * mac80211. That also explains the __skb_push()
1789 		 * below.
1790 		 */
1791 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1792 		if (align) {
1793 			if (WARN_ON(skb_headroom(skb) < 3)) {
1794 				dev_kfree_skb(skb);
1795 				skb = NULL;
1796 			} else {
1797 				u8 *data = skb->data;
1798 				size_t len = skb_headlen(skb);
1799 				skb->data -= align;
1800 				memmove(skb->data, data, len);
1801 				skb_set_tail_pointer(skb, len);
1802 			}
1803 		}
1804 #endif
1805 
1806 		if (skb) {
1807 			/* deliver to local stack */
1808 			skb->protocol = eth_type_trans(skb, dev);
1809 			memset(skb->cb, 0, sizeof(skb->cb));
1810 			netif_receive_skb(skb);
1811 		}
1812 	}
1813 
1814 	if (xmit_skb) {
1815 		/*
1816 		 * Send to wireless media and increase priority by 256 to
1817 		 * keep the received priority instead of reclassifying
1818 		 * the frame (see cfg80211_classify8021d).
1819 		 */
1820 		xmit_skb->priority += 256;
1821 		xmit_skb->protocol = htons(ETH_P_802_3);
1822 		skb_reset_network_header(xmit_skb);
1823 		skb_reset_mac_header(xmit_skb);
1824 		dev_queue_xmit(xmit_skb);
1825 	}
1826 }
1827 
1828 static ieee80211_rx_result debug_noinline
1829 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1830 {
1831 	struct net_device *dev = rx->sdata->dev;
1832 	struct sk_buff *skb = rx->skb;
1833 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1834 	__le16 fc = hdr->frame_control;
1835 	struct sk_buff_head frame_list;
1836 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1837 
1838 	if (unlikely(!ieee80211_is_data(fc)))
1839 		return RX_CONTINUE;
1840 
1841 	if (unlikely(!ieee80211_is_data_present(fc)))
1842 		return RX_DROP_MONITOR;
1843 
1844 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1845 		return RX_CONTINUE;
1846 
1847 	if (ieee80211_has_a4(hdr->frame_control) &&
1848 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1849 	    !rx->sdata->u.vlan.sta)
1850 		return RX_DROP_UNUSABLE;
1851 
1852 	if (is_multicast_ether_addr(hdr->addr1) &&
1853 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1854 	      rx->sdata->u.vlan.sta) ||
1855 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1856 	      rx->sdata->u.mgd.use_4addr)))
1857 		return RX_DROP_UNUSABLE;
1858 
1859 	skb->dev = dev;
1860 	__skb_queue_head_init(&frame_list);
1861 
1862 	if (skb_linearize(skb))
1863 		return RX_DROP_UNUSABLE;
1864 
1865 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1866 				 rx->sdata->vif.type,
1867 				 rx->local->hw.extra_tx_headroom, true);
1868 
1869 	while (!skb_queue_empty(&frame_list)) {
1870 		rx->skb = __skb_dequeue(&frame_list);
1871 
1872 		if (!ieee80211_frame_allowed(rx, fc)) {
1873 			dev_kfree_skb(rx->skb);
1874 			continue;
1875 		}
1876 		dev->stats.rx_packets++;
1877 		dev->stats.rx_bytes += rx->skb->len;
1878 
1879 		ieee80211_deliver_skb(rx);
1880 	}
1881 
1882 	return RX_QUEUED;
1883 }
1884 
1885 #ifdef CONFIG_MAC80211_MESH
1886 static ieee80211_rx_result
1887 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1888 {
1889 	struct ieee80211_hdr *fwd_hdr, *hdr;
1890 	struct ieee80211_tx_info *info;
1891 	struct ieee80211s_hdr *mesh_hdr;
1892 	struct sk_buff *skb = rx->skb, *fwd_skb;
1893 	struct ieee80211_local *local = rx->local;
1894 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1895 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1896 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1897 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1898 	u16 q, hdrlen;
1899 
1900 	hdr = (struct ieee80211_hdr *) skb->data;
1901 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1902 
1903 	/* make sure fixed part of mesh header is there, also checks skb len */
1904 	if (!pskb_may_pull(rx->skb, hdrlen + 6))
1905 		return RX_DROP_MONITOR;
1906 
1907 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1908 
1909 	/* make sure full mesh header is there, also checks skb len */
1910 	if (!pskb_may_pull(rx->skb,
1911 			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
1912 		return RX_DROP_MONITOR;
1913 
1914 	/* reload pointers */
1915 	hdr = (struct ieee80211_hdr *) skb->data;
1916 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1917 
1918 	/* frame is in RMC, don't forward */
1919 	if (ieee80211_is_data(hdr->frame_control) &&
1920 	    is_multicast_ether_addr(hdr->addr1) &&
1921 	    mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1922 		return RX_DROP_MONITOR;
1923 
1924 	if (!ieee80211_is_data(hdr->frame_control) ||
1925 	    !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1926 		return RX_CONTINUE;
1927 
1928 	if (!mesh_hdr->ttl)
1929 		return RX_DROP_MONITOR;
1930 
1931 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
1932 		struct mesh_path *mppath;
1933 		char *proxied_addr;
1934 		char *mpp_addr;
1935 
1936 		if (is_multicast_ether_addr(hdr->addr1)) {
1937 			mpp_addr = hdr->addr3;
1938 			proxied_addr = mesh_hdr->eaddr1;
1939 		} else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
1940 			/* has_a4 already checked in ieee80211_rx_mesh_check */
1941 			mpp_addr = hdr->addr4;
1942 			proxied_addr = mesh_hdr->eaddr2;
1943 		} else {
1944 			return RX_DROP_MONITOR;
1945 		}
1946 
1947 		rcu_read_lock();
1948 		mppath = mpp_path_lookup(proxied_addr, sdata);
1949 		if (!mppath) {
1950 			mpp_path_add(proxied_addr, mpp_addr, sdata);
1951 		} else {
1952 			spin_lock_bh(&mppath->state_lock);
1953 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
1954 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1955 			spin_unlock_bh(&mppath->state_lock);
1956 		}
1957 		rcu_read_unlock();
1958 	}
1959 
1960 	/* Frame has reached destination.  Don't forward */
1961 	if (!is_multicast_ether_addr(hdr->addr1) &&
1962 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
1963 		return RX_CONTINUE;
1964 
1965 	q = ieee80211_select_queue_80211(sdata, skb, hdr);
1966 	if (ieee80211_queue_stopped(&local->hw, q)) {
1967 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1968 		return RX_DROP_MONITOR;
1969 	}
1970 	skb_set_queue_mapping(skb, q);
1971 
1972 	if (!--mesh_hdr->ttl) {
1973 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1974 		goto out;
1975 	}
1976 
1977 	if (!ifmsh->mshcfg.dot11MeshForwarding)
1978 		goto out;
1979 
1980 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
1981 	if (!fwd_skb) {
1982 		net_info_ratelimited("%s: failed to clone mesh frame\n",
1983 				    sdata->name);
1984 		goto out;
1985 	}
1986 
1987 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1988 	info = IEEE80211_SKB_CB(fwd_skb);
1989 	memset(info, 0, sizeof(*info));
1990 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1991 	info->control.vif = &rx->sdata->vif;
1992 	info->control.jiffies = jiffies;
1993 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1994 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1995 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1996 	} else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1997 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1998 	} else {
1999 		/* unable to resolve next hop */
2000 		mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
2001 				    0, reason, fwd_hdr->addr2, sdata);
2002 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2003 		kfree_skb(fwd_skb);
2004 		return RX_DROP_MONITOR;
2005 	}
2006 
2007 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2008 	ieee80211_add_pending_skb(local, fwd_skb);
2009  out:
2010 	if (is_multicast_ether_addr(hdr->addr1) ||
2011 	    sdata->dev->flags & IFF_PROMISC)
2012 		return RX_CONTINUE;
2013 	else
2014 		return RX_DROP_MONITOR;
2015 }
2016 #endif
2017 
2018 static ieee80211_rx_result debug_noinline
2019 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2020 {
2021 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2022 	struct ieee80211_local *local = rx->local;
2023 	struct net_device *dev = sdata->dev;
2024 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2025 	__le16 fc = hdr->frame_control;
2026 	bool port_control;
2027 	int err;
2028 
2029 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2030 		return RX_CONTINUE;
2031 
2032 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2033 		return RX_DROP_MONITOR;
2034 
2035 	/*
2036 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2037 	 * also drop the frame to cooked monitor interfaces.
2038 	 */
2039 	if (ieee80211_has_a4(hdr->frame_control) &&
2040 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2041 		if (rx->sta &&
2042 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2043 			cfg80211_rx_unexpected_4addr_frame(
2044 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2045 		return RX_DROP_MONITOR;
2046 	}
2047 
2048 	err = __ieee80211_data_to_8023(rx, &port_control);
2049 	if (unlikely(err))
2050 		return RX_DROP_UNUSABLE;
2051 
2052 	if (!ieee80211_frame_allowed(rx, fc))
2053 		return RX_DROP_MONITOR;
2054 
2055 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2056 	    unlikely(port_control) && sdata->bss) {
2057 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2058 				     u.ap);
2059 		dev = sdata->dev;
2060 		rx->sdata = sdata;
2061 	}
2062 
2063 	rx->skb->dev = dev;
2064 
2065 	dev->stats.rx_packets++;
2066 	dev->stats.rx_bytes += rx->skb->len;
2067 
2068 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2069 	    !is_multicast_ether_addr(
2070 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2071 	    (!local->scanning &&
2072 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2073 			mod_timer(&local->dynamic_ps_timer, jiffies +
2074 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2075 	}
2076 
2077 	ieee80211_deliver_skb(rx);
2078 
2079 	return RX_QUEUED;
2080 }
2081 
2082 static ieee80211_rx_result debug_noinline
2083 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2084 {
2085 	struct sk_buff *skb = rx->skb;
2086 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2087 	struct tid_ampdu_rx *tid_agg_rx;
2088 	u16 start_seq_num;
2089 	u16 tid;
2090 
2091 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2092 		return RX_CONTINUE;
2093 
2094 	if (ieee80211_is_back_req(bar->frame_control)) {
2095 		struct {
2096 			__le16 control, start_seq_num;
2097 		} __packed bar_data;
2098 
2099 		if (!rx->sta)
2100 			return RX_DROP_MONITOR;
2101 
2102 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2103 				  &bar_data, sizeof(bar_data)))
2104 			return RX_DROP_MONITOR;
2105 
2106 		tid = le16_to_cpu(bar_data.control) >> 12;
2107 
2108 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2109 		if (!tid_agg_rx)
2110 			return RX_DROP_MONITOR;
2111 
2112 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2113 
2114 		/* reset session timer */
2115 		if (tid_agg_rx->timeout)
2116 			mod_timer(&tid_agg_rx->session_timer,
2117 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2118 
2119 		spin_lock(&tid_agg_rx->reorder_lock);
2120 		/* release stored frames up to start of BAR */
2121 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2122 						 start_seq_num);
2123 		spin_unlock(&tid_agg_rx->reorder_lock);
2124 
2125 		kfree_skb(skb);
2126 		return RX_QUEUED;
2127 	}
2128 
2129 	/*
2130 	 * After this point, we only want management frames,
2131 	 * so we can drop all remaining control frames to
2132 	 * cooked monitor interfaces.
2133 	 */
2134 	return RX_DROP_MONITOR;
2135 }
2136 
2137 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2138 					   struct ieee80211_mgmt *mgmt,
2139 					   size_t len)
2140 {
2141 	struct ieee80211_local *local = sdata->local;
2142 	struct sk_buff *skb;
2143 	struct ieee80211_mgmt *resp;
2144 
2145 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2146 		/* Not to own unicast address */
2147 		return;
2148 	}
2149 
2150 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2151 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2152 		/* Not from the current AP or not associated yet. */
2153 		return;
2154 	}
2155 
2156 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2157 		/* Too short SA Query request frame */
2158 		return;
2159 	}
2160 
2161 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2162 	if (skb == NULL)
2163 		return;
2164 
2165 	skb_reserve(skb, local->hw.extra_tx_headroom);
2166 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2167 	memset(resp, 0, 24);
2168 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2169 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2170 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2171 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2172 					  IEEE80211_STYPE_ACTION);
2173 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2174 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2175 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2176 	memcpy(resp->u.action.u.sa_query.trans_id,
2177 	       mgmt->u.action.u.sa_query.trans_id,
2178 	       WLAN_SA_QUERY_TR_ID_LEN);
2179 
2180 	ieee80211_tx_skb(sdata, skb);
2181 }
2182 
2183 static ieee80211_rx_result debug_noinline
2184 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2185 {
2186 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2187 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2188 
2189 	/*
2190 	 * From here on, look only at management frames.
2191 	 * Data and control frames are already handled,
2192 	 * and unknown (reserved) frames are useless.
2193 	 */
2194 	if (rx->skb->len < 24)
2195 		return RX_DROP_MONITOR;
2196 
2197 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2198 		return RX_DROP_MONITOR;
2199 
2200 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2201 	    ieee80211_is_beacon(mgmt->frame_control) &&
2202 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2203 		int sig = 0;
2204 
2205 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2206 			sig = status->signal;
2207 
2208 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2209 					    rx->skb->data, rx->skb->len,
2210 					    status->freq, sig, GFP_ATOMIC);
2211 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2212 	}
2213 
2214 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2215 		return RX_DROP_MONITOR;
2216 
2217 	if (ieee80211_drop_unencrypted_mgmt(rx))
2218 		return RX_DROP_UNUSABLE;
2219 
2220 	return RX_CONTINUE;
2221 }
2222 
2223 static ieee80211_rx_result debug_noinline
2224 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2225 {
2226 	struct ieee80211_local *local = rx->local;
2227 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2228 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2229 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2230 	int len = rx->skb->len;
2231 
2232 	if (!ieee80211_is_action(mgmt->frame_control))
2233 		return RX_CONTINUE;
2234 
2235 	/* drop too small frames */
2236 	if (len < IEEE80211_MIN_ACTION_SIZE)
2237 		return RX_DROP_UNUSABLE;
2238 
2239 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2240 		return RX_DROP_UNUSABLE;
2241 
2242 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2243 		return RX_DROP_UNUSABLE;
2244 
2245 	switch (mgmt->u.action.category) {
2246 	case WLAN_CATEGORY_HT:
2247 		/* reject HT action frames from stations not supporting HT */
2248 		if (!rx->sta->sta.ht_cap.ht_supported)
2249 			goto invalid;
2250 
2251 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2252 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2253 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2254 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2255 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2256 			break;
2257 
2258 		/* verify action & smps_control are present */
2259 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2260 			goto invalid;
2261 
2262 		switch (mgmt->u.action.u.ht_smps.action) {
2263 		case WLAN_HT_ACTION_SMPS: {
2264 			struct ieee80211_supported_band *sband;
2265 			u8 smps;
2266 
2267 			/* convert to HT capability */
2268 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2269 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2270 				smps = WLAN_HT_CAP_SM_PS_DISABLED;
2271 				break;
2272 			case WLAN_HT_SMPS_CONTROL_STATIC:
2273 				smps = WLAN_HT_CAP_SM_PS_STATIC;
2274 				break;
2275 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2276 				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2277 				break;
2278 			default:
2279 				goto invalid;
2280 			}
2281 			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2282 
2283 			/* if no change do nothing */
2284 			if ((rx->sta->sta.ht_cap.cap &
2285 					IEEE80211_HT_CAP_SM_PS) == smps)
2286 				goto handled;
2287 
2288 			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2289 			rx->sta->sta.ht_cap.cap |= smps;
2290 
2291 			sband = rx->local->hw.wiphy->bands[status->band];
2292 
2293 			rate_control_rate_update(local, sband, rx->sta,
2294 						 IEEE80211_RC_SMPS_CHANGED);
2295 			goto handled;
2296 		}
2297 		default:
2298 			goto invalid;
2299 		}
2300 
2301 		break;
2302 	case WLAN_CATEGORY_BACK:
2303 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2304 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2305 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2306 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2307 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2308 			break;
2309 
2310 		/* verify action_code is present */
2311 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2312 			break;
2313 
2314 		switch (mgmt->u.action.u.addba_req.action_code) {
2315 		case WLAN_ACTION_ADDBA_REQ:
2316 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2317 				   sizeof(mgmt->u.action.u.addba_req)))
2318 				goto invalid;
2319 			break;
2320 		case WLAN_ACTION_ADDBA_RESP:
2321 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2322 				   sizeof(mgmt->u.action.u.addba_resp)))
2323 				goto invalid;
2324 			break;
2325 		case WLAN_ACTION_DELBA:
2326 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2327 				   sizeof(mgmt->u.action.u.delba)))
2328 				goto invalid;
2329 			break;
2330 		default:
2331 			goto invalid;
2332 		}
2333 
2334 		goto queue;
2335 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2336 		if (status->band != IEEE80211_BAND_5GHZ)
2337 			break;
2338 
2339 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2340 			break;
2341 
2342 		/* verify action_code is present */
2343 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2344 			break;
2345 
2346 		switch (mgmt->u.action.u.measurement.action_code) {
2347 		case WLAN_ACTION_SPCT_MSR_REQ:
2348 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2349 				   sizeof(mgmt->u.action.u.measurement)))
2350 				break;
2351 			ieee80211_process_measurement_req(sdata, mgmt, len);
2352 			goto handled;
2353 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2354 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2355 				   sizeof(mgmt->u.action.u.chan_switch)))
2356 				break;
2357 
2358 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2359 				break;
2360 
2361 			if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2362 				break;
2363 
2364 			goto queue;
2365 		}
2366 		break;
2367 	case WLAN_CATEGORY_SA_QUERY:
2368 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2369 			   sizeof(mgmt->u.action.u.sa_query)))
2370 			break;
2371 
2372 		switch (mgmt->u.action.u.sa_query.action) {
2373 		case WLAN_ACTION_SA_QUERY_REQUEST:
2374 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2375 				break;
2376 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2377 			goto handled;
2378 		}
2379 		break;
2380 	case WLAN_CATEGORY_SELF_PROTECTED:
2381 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2382 			   sizeof(mgmt->u.action.u.self_prot.action_code)))
2383 			break;
2384 
2385 		switch (mgmt->u.action.u.self_prot.action_code) {
2386 		case WLAN_SP_MESH_PEERING_OPEN:
2387 		case WLAN_SP_MESH_PEERING_CLOSE:
2388 		case WLAN_SP_MESH_PEERING_CONFIRM:
2389 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2390 				goto invalid;
2391 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2392 				/* userspace handles this frame */
2393 				break;
2394 			goto queue;
2395 		case WLAN_SP_MGK_INFORM:
2396 		case WLAN_SP_MGK_ACK:
2397 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2398 				goto invalid;
2399 			break;
2400 		}
2401 		break;
2402 	case WLAN_CATEGORY_MESH_ACTION:
2403 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2404 			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
2405 			break;
2406 
2407 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2408 			break;
2409 		if (mesh_action_is_path_sel(mgmt) &&
2410 		  (!mesh_path_sel_is_hwmp(sdata)))
2411 			break;
2412 		goto queue;
2413 	}
2414 
2415 	return RX_CONTINUE;
2416 
2417  invalid:
2418 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2419 	/* will return in the next handlers */
2420 	return RX_CONTINUE;
2421 
2422  handled:
2423 	if (rx->sta)
2424 		rx->sta->rx_packets++;
2425 	dev_kfree_skb(rx->skb);
2426 	return RX_QUEUED;
2427 
2428  queue:
2429 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2430 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2431 	ieee80211_queue_work(&local->hw, &sdata->work);
2432 	if (rx->sta)
2433 		rx->sta->rx_packets++;
2434 	return RX_QUEUED;
2435 }
2436 
2437 static ieee80211_rx_result debug_noinline
2438 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2439 {
2440 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2441 	int sig = 0;
2442 
2443 	/* skip known-bad action frames and return them in the next handler */
2444 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2445 		return RX_CONTINUE;
2446 
2447 	/*
2448 	 * Getting here means the kernel doesn't know how to handle
2449 	 * it, but maybe userspace does ... include returned frames
2450 	 * so userspace can register for those to know whether ones
2451 	 * it transmitted were processed or returned.
2452 	 */
2453 
2454 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2455 		sig = status->signal;
2456 
2457 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2458 			     rx->skb->data, rx->skb->len,
2459 			     GFP_ATOMIC)) {
2460 		if (rx->sta)
2461 			rx->sta->rx_packets++;
2462 		dev_kfree_skb(rx->skb);
2463 		return RX_QUEUED;
2464 	}
2465 
2466 
2467 	return RX_CONTINUE;
2468 }
2469 
2470 static ieee80211_rx_result debug_noinline
2471 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2472 {
2473 	struct ieee80211_local *local = rx->local;
2474 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2475 	struct sk_buff *nskb;
2476 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2477 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2478 
2479 	if (!ieee80211_is_action(mgmt->frame_control))
2480 		return RX_CONTINUE;
2481 
2482 	/*
2483 	 * For AP mode, hostapd is responsible for handling any action
2484 	 * frames that we didn't handle, including returning unknown
2485 	 * ones. For all other modes we will return them to the sender,
2486 	 * setting the 0x80 bit in the action category, as required by
2487 	 * 802.11-2012 9.24.4.
2488 	 * Newer versions of hostapd shall also use the management frame
2489 	 * registration mechanisms, but older ones still use cooked
2490 	 * monitor interfaces so push all frames there.
2491 	 */
2492 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2493 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2494 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2495 		return RX_DROP_MONITOR;
2496 
2497 	if (is_multicast_ether_addr(mgmt->da))
2498 		return RX_DROP_MONITOR;
2499 
2500 	/* do not return rejected action frames */
2501 	if (mgmt->u.action.category & 0x80)
2502 		return RX_DROP_UNUSABLE;
2503 
2504 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2505 			       GFP_ATOMIC);
2506 	if (nskb) {
2507 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2508 
2509 		nmgmt->u.action.category |= 0x80;
2510 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2511 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2512 
2513 		memset(nskb->cb, 0, sizeof(nskb->cb));
2514 
2515 		ieee80211_tx_skb(rx->sdata, nskb);
2516 	}
2517 	dev_kfree_skb(rx->skb);
2518 	return RX_QUEUED;
2519 }
2520 
2521 static ieee80211_rx_result debug_noinline
2522 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2523 {
2524 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2525 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2526 	__le16 stype;
2527 
2528 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2529 
2530 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2531 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2532 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2533 		return RX_DROP_MONITOR;
2534 
2535 	switch (stype) {
2536 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2537 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2538 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2539 		/* process for all: mesh, mlme, ibss */
2540 		break;
2541 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2542 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2543 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2544 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2545 		if (is_multicast_ether_addr(mgmt->da) &&
2546 		    !is_broadcast_ether_addr(mgmt->da))
2547 			return RX_DROP_MONITOR;
2548 
2549 		/* process only for station */
2550 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2551 			return RX_DROP_MONITOR;
2552 		break;
2553 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2554 		/* process only for ibss */
2555 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2556 			return RX_DROP_MONITOR;
2557 		break;
2558 	default:
2559 		return RX_DROP_MONITOR;
2560 	}
2561 
2562 	/* queue up frame and kick off work to process it */
2563 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2564 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2565 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2566 	if (rx->sta)
2567 		rx->sta->rx_packets++;
2568 
2569 	return RX_QUEUED;
2570 }
2571 
2572 /* TODO: use IEEE80211_RX_FRAGMENTED */
2573 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2574 					struct ieee80211_rate *rate)
2575 {
2576 	struct ieee80211_sub_if_data *sdata;
2577 	struct ieee80211_local *local = rx->local;
2578 	struct sk_buff *skb = rx->skb, *skb2;
2579 	struct net_device *prev_dev = NULL;
2580 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2581 	int needed_headroom;
2582 
2583 	/*
2584 	 * If cooked monitor has been processed already, then
2585 	 * don't do it again. If not, set the flag.
2586 	 */
2587 	if (rx->flags & IEEE80211_RX_CMNTR)
2588 		goto out_free_skb;
2589 	rx->flags |= IEEE80211_RX_CMNTR;
2590 
2591 	/* If there are no cooked monitor interfaces, just free the SKB */
2592 	if (!local->cooked_mntrs)
2593 		goto out_free_skb;
2594 
2595 	/* room for the radiotap header based on driver features */
2596 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
2597 
2598 	if (skb_headroom(skb) < needed_headroom &&
2599 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2600 		goto out_free_skb;
2601 
2602 	/* prepend radiotap information */
2603 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2604 					 false);
2605 
2606 	skb_set_mac_header(skb, 0);
2607 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2608 	skb->pkt_type = PACKET_OTHERHOST;
2609 	skb->protocol = htons(ETH_P_802_2);
2610 
2611 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2612 		if (!ieee80211_sdata_running(sdata))
2613 			continue;
2614 
2615 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2616 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2617 			continue;
2618 
2619 		if (prev_dev) {
2620 			skb2 = skb_clone(skb, GFP_ATOMIC);
2621 			if (skb2) {
2622 				skb2->dev = prev_dev;
2623 				netif_receive_skb(skb2);
2624 			}
2625 		}
2626 
2627 		prev_dev = sdata->dev;
2628 		sdata->dev->stats.rx_packets++;
2629 		sdata->dev->stats.rx_bytes += skb->len;
2630 	}
2631 
2632 	if (prev_dev) {
2633 		skb->dev = prev_dev;
2634 		netif_receive_skb(skb);
2635 		return;
2636 	}
2637 
2638  out_free_skb:
2639 	dev_kfree_skb(skb);
2640 }
2641 
2642 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2643 					 ieee80211_rx_result res)
2644 {
2645 	switch (res) {
2646 	case RX_DROP_MONITOR:
2647 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2648 		if (rx->sta)
2649 			rx->sta->rx_dropped++;
2650 		/* fall through */
2651 	case RX_CONTINUE: {
2652 		struct ieee80211_rate *rate = NULL;
2653 		struct ieee80211_supported_band *sband;
2654 		struct ieee80211_rx_status *status;
2655 
2656 		status = IEEE80211_SKB_RXCB((rx->skb));
2657 
2658 		sband = rx->local->hw.wiphy->bands[status->band];
2659 		if (!(status->flag & RX_FLAG_HT))
2660 			rate = &sband->bitrates[status->rate_idx];
2661 
2662 		ieee80211_rx_cooked_monitor(rx, rate);
2663 		break;
2664 		}
2665 	case RX_DROP_UNUSABLE:
2666 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2667 		if (rx->sta)
2668 			rx->sta->rx_dropped++;
2669 		dev_kfree_skb(rx->skb);
2670 		break;
2671 	case RX_QUEUED:
2672 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2673 		break;
2674 	}
2675 }
2676 
2677 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2678 {
2679 	ieee80211_rx_result res = RX_DROP_MONITOR;
2680 	struct sk_buff *skb;
2681 
2682 #define CALL_RXH(rxh)			\
2683 	do {				\
2684 		res = rxh(rx);		\
2685 		if (res != RX_CONTINUE)	\
2686 			goto rxh_next;  \
2687 	} while (0);
2688 
2689 	spin_lock(&rx->local->rx_skb_queue.lock);
2690 	if (rx->local->running_rx_handler)
2691 		goto unlock;
2692 
2693 	rx->local->running_rx_handler = true;
2694 
2695 	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2696 		spin_unlock(&rx->local->rx_skb_queue.lock);
2697 
2698 		/*
2699 		 * all the other fields are valid across frames
2700 		 * that belong to an aMPDU since they are on the
2701 		 * same TID from the same station
2702 		 */
2703 		rx->skb = skb;
2704 
2705 		CALL_RXH(ieee80211_rx_h_decrypt)
2706 		CALL_RXH(ieee80211_rx_h_check_more_data)
2707 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2708 		CALL_RXH(ieee80211_rx_h_sta_process)
2709 		CALL_RXH(ieee80211_rx_h_defragment)
2710 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2711 		/* must be after MMIC verify so header is counted in MPDU mic */
2712 #ifdef CONFIG_MAC80211_MESH
2713 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2714 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2715 #endif
2716 		CALL_RXH(ieee80211_rx_h_amsdu)
2717 		CALL_RXH(ieee80211_rx_h_data)
2718 		CALL_RXH(ieee80211_rx_h_ctrl);
2719 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2720 		CALL_RXH(ieee80211_rx_h_action)
2721 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2722 		CALL_RXH(ieee80211_rx_h_action_return)
2723 		CALL_RXH(ieee80211_rx_h_mgmt)
2724 
2725  rxh_next:
2726 		ieee80211_rx_handlers_result(rx, res);
2727 		spin_lock(&rx->local->rx_skb_queue.lock);
2728 #undef CALL_RXH
2729 	}
2730 
2731 	rx->local->running_rx_handler = false;
2732 
2733  unlock:
2734 	spin_unlock(&rx->local->rx_skb_queue.lock);
2735 }
2736 
2737 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2738 {
2739 	ieee80211_rx_result res = RX_DROP_MONITOR;
2740 
2741 #define CALL_RXH(rxh)			\
2742 	do {				\
2743 		res = rxh(rx);		\
2744 		if (res != RX_CONTINUE)	\
2745 			goto rxh_next;  \
2746 	} while (0);
2747 
2748 	CALL_RXH(ieee80211_rx_h_check)
2749 
2750 	ieee80211_rx_reorder_ampdu(rx);
2751 
2752 	ieee80211_rx_handlers(rx);
2753 	return;
2754 
2755  rxh_next:
2756 	ieee80211_rx_handlers_result(rx, res);
2757 
2758 #undef CALL_RXH
2759 }
2760 
2761 /*
2762  * This function makes calls into the RX path, therefore
2763  * it has to be invoked under RCU read lock.
2764  */
2765 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2766 {
2767 	struct ieee80211_rx_data rx = {
2768 		.sta = sta,
2769 		.sdata = sta->sdata,
2770 		.local = sta->local,
2771 		/* This is OK -- must be QoS data frame */
2772 		.security_idx = tid,
2773 		.seqno_idx = tid,
2774 		.flags = 0,
2775 	};
2776 	struct tid_ampdu_rx *tid_agg_rx;
2777 
2778 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2779 	if (!tid_agg_rx)
2780 		return;
2781 
2782 	spin_lock(&tid_agg_rx->reorder_lock);
2783 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx);
2784 	spin_unlock(&tid_agg_rx->reorder_lock);
2785 
2786 	ieee80211_rx_handlers(&rx);
2787 }
2788 
2789 /* main receive path */
2790 
2791 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2792 				struct ieee80211_hdr *hdr)
2793 {
2794 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2795 	struct sk_buff *skb = rx->skb;
2796 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2797 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2798 	int multicast = is_multicast_ether_addr(hdr->addr1);
2799 
2800 	switch (sdata->vif.type) {
2801 	case NL80211_IFTYPE_STATION:
2802 		if (!bssid && !sdata->u.mgd.use_4addr)
2803 			return 0;
2804 		if (!multicast &&
2805 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2806 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2807 			    sdata->u.mgd.use_4addr)
2808 				return 0;
2809 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2810 		}
2811 		break;
2812 	case NL80211_IFTYPE_ADHOC:
2813 		if (!bssid)
2814 			return 0;
2815 		if (ieee80211_is_beacon(hdr->frame_control)) {
2816 			return 1;
2817 		} else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2818 			return 0;
2819 		} else if (!multicast &&
2820 			   !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2821 			if (!(sdata->dev->flags & IFF_PROMISC))
2822 				return 0;
2823 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2824 		} else if (!rx->sta) {
2825 			int rate_idx;
2826 			if (status->flag & RX_FLAG_HT)
2827 				rate_idx = 0; /* TODO: HT rates */
2828 			else
2829 				rate_idx = status->rate_idx;
2830 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2831 						 BIT(rate_idx));
2832 		}
2833 		break;
2834 	case NL80211_IFTYPE_MESH_POINT:
2835 		if (!multicast &&
2836 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2837 			if (!(sdata->dev->flags & IFF_PROMISC))
2838 				return 0;
2839 
2840 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2841 		}
2842 		break;
2843 	case NL80211_IFTYPE_AP_VLAN:
2844 	case NL80211_IFTYPE_AP:
2845 		if (!bssid) {
2846 			if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2847 				return 0;
2848 		} else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
2849 			/*
2850 			 * Accept public action frames even when the
2851 			 * BSSID doesn't match, this is used for P2P
2852 			 * and location updates. Note that mac80211
2853 			 * itself never looks at these frames.
2854 			 */
2855 			if (ieee80211_is_public_action(hdr, skb->len))
2856 				return 1;
2857 			if (!ieee80211_is_beacon(hdr->frame_control))
2858 				return 0;
2859 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2860 		}
2861 		break;
2862 	case NL80211_IFTYPE_WDS:
2863 		if (bssid || !ieee80211_is_data(hdr->frame_control))
2864 			return 0;
2865 		if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
2866 			return 0;
2867 		break;
2868 	case NL80211_IFTYPE_P2P_DEVICE:
2869 		if (!ieee80211_is_public_action(hdr, skb->len) &&
2870 		    !ieee80211_is_probe_req(hdr->frame_control) &&
2871 		    !ieee80211_is_probe_resp(hdr->frame_control) &&
2872 		    !ieee80211_is_beacon(hdr->frame_control))
2873 			return 0;
2874 		if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2875 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2876 		break;
2877 	default:
2878 		/* should never get here */
2879 		WARN_ON_ONCE(1);
2880 		break;
2881 	}
2882 
2883 	return 1;
2884 }
2885 
2886 /*
2887  * This function returns whether or not the SKB
2888  * was destined for RX processing or not, which,
2889  * if consume is true, is equivalent to whether
2890  * or not the skb was consumed.
2891  */
2892 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2893 					    struct sk_buff *skb, bool consume)
2894 {
2895 	struct ieee80211_local *local = rx->local;
2896 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2897 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2898 	struct ieee80211_hdr *hdr = (void *)skb->data;
2899 	int prepares;
2900 
2901 	rx->skb = skb;
2902 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
2903 	prepares = prepare_for_handlers(rx, hdr);
2904 
2905 	if (!prepares)
2906 		return false;
2907 
2908 	if (!consume) {
2909 		skb = skb_copy(skb, GFP_ATOMIC);
2910 		if (!skb) {
2911 			if (net_ratelimit())
2912 				wiphy_debug(local->hw.wiphy,
2913 					"failed to copy skb for %s\n",
2914 					sdata->name);
2915 			return true;
2916 		}
2917 
2918 		rx->skb = skb;
2919 	}
2920 
2921 	ieee80211_invoke_rx_handlers(rx);
2922 	return true;
2923 }
2924 
2925 /*
2926  * This is the actual Rx frames handler. as it blongs to Rx path it must
2927  * be called with rcu_read_lock protection.
2928  */
2929 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2930 					 struct sk_buff *skb)
2931 {
2932 	struct ieee80211_local *local = hw_to_local(hw);
2933 	struct ieee80211_sub_if_data *sdata;
2934 	struct ieee80211_hdr *hdr;
2935 	__le16 fc;
2936 	struct ieee80211_rx_data rx;
2937 	struct ieee80211_sub_if_data *prev;
2938 	struct sta_info *sta, *tmp, *prev_sta;
2939 	int err = 0;
2940 
2941 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2942 	memset(&rx, 0, sizeof(rx));
2943 	rx.skb = skb;
2944 	rx.local = local;
2945 
2946 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2947 		local->dot11ReceivedFragmentCount++;
2948 
2949 	if (ieee80211_is_mgmt(fc)) {
2950 		/* drop frame if too short for header */
2951 		if (skb->len < ieee80211_hdrlen(fc))
2952 			err = -ENOBUFS;
2953 		else
2954 			err = skb_linearize(skb);
2955 	} else {
2956 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2957 	}
2958 
2959 	if (err) {
2960 		dev_kfree_skb(skb);
2961 		return;
2962 	}
2963 
2964 	hdr = (struct ieee80211_hdr *)skb->data;
2965 	ieee80211_parse_qos(&rx);
2966 	ieee80211_verify_alignment(&rx);
2967 
2968 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
2969 		     ieee80211_is_beacon(hdr->frame_control)))
2970 		ieee80211_scan_rx(local, skb);
2971 
2972 	if (ieee80211_is_data(fc)) {
2973 		prev_sta = NULL;
2974 
2975 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
2976 			if (!prev_sta) {
2977 				prev_sta = sta;
2978 				continue;
2979 			}
2980 
2981 			rx.sta = prev_sta;
2982 			rx.sdata = prev_sta->sdata;
2983 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
2984 
2985 			prev_sta = sta;
2986 		}
2987 
2988 		if (prev_sta) {
2989 			rx.sta = prev_sta;
2990 			rx.sdata = prev_sta->sdata;
2991 
2992 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2993 				return;
2994 			goto out;
2995 		}
2996 	}
2997 
2998 	prev = NULL;
2999 
3000 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3001 		if (!ieee80211_sdata_running(sdata))
3002 			continue;
3003 
3004 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3005 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3006 			continue;
3007 
3008 		/*
3009 		 * frame is destined for this interface, but if it's
3010 		 * not also for the previous one we handle that after
3011 		 * the loop to avoid copying the SKB once too much
3012 		 */
3013 
3014 		if (!prev) {
3015 			prev = sdata;
3016 			continue;
3017 		}
3018 
3019 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3020 		rx.sdata = prev;
3021 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
3022 
3023 		prev = sdata;
3024 	}
3025 
3026 	if (prev) {
3027 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
3028 		rx.sdata = prev;
3029 
3030 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3031 			return;
3032 	}
3033 
3034  out:
3035 	dev_kfree_skb(skb);
3036 }
3037 
3038 /*
3039  * This is the receive path handler. It is called by a low level driver when an
3040  * 802.11 MPDU is received from the hardware.
3041  */
3042 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3043 {
3044 	struct ieee80211_local *local = hw_to_local(hw);
3045 	struct ieee80211_rate *rate = NULL;
3046 	struct ieee80211_supported_band *sband;
3047 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3048 
3049 	WARN_ON_ONCE(softirq_count() == 0);
3050 
3051 	if (WARN_ON(status->band < 0 ||
3052 		    status->band >= IEEE80211_NUM_BANDS))
3053 		goto drop;
3054 
3055 	sband = local->hw.wiphy->bands[status->band];
3056 	if (WARN_ON(!sband))
3057 		goto drop;
3058 
3059 	/*
3060 	 * If we're suspending, it is possible although not too likely
3061 	 * that we'd be receiving frames after having already partially
3062 	 * quiesced the stack. We can't process such frames then since
3063 	 * that might, for example, cause stations to be added or other
3064 	 * driver callbacks be invoked.
3065 	 */
3066 	if (unlikely(local->quiescing || local->suspended))
3067 		goto drop;
3068 
3069 	/* We might be during a HW reconfig, prevent Rx for the same reason */
3070 	if (unlikely(local->in_reconfig))
3071 		goto drop;
3072 
3073 	/*
3074 	 * The same happens when we're not even started,
3075 	 * but that's worth a warning.
3076 	 */
3077 	if (WARN_ON(!local->started))
3078 		goto drop;
3079 
3080 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3081 		/*
3082 		 * Validate the rate, unless a PLCP error means that
3083 		 * we probably can't have a valid rate here anyway.
3084 		 */
3085 
3086 		if (status->flag & RX_FLAG_HT) {
3087 			/*
3088 			 * rate_idx is MCS index, which can be [0-76]
3089 			 * as documented on:
3090 			 *
3091 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3092 			 *
3093 			 * Anything else would be some sort of driver or
3094 			 * hardware error. The driver should catch hardware
3095 			 * errors.
3096 			 */
3097 			if (WARN((status->rate_idx < 0 ||
3098 				 status->rate_idx > 76),
3099 				 "Rate marked as an HT rate but passed "
3100 				 "status->rate_idx is not "
3101 				 "an MCS index [0-76]: %d (0x%02x)\n",
3102 				 status->rate_idx,
3103 				 status->rate_idx))
3104 				goto drop;
3105 		} else {
3106 			if (WARN_ON(status->rate_idx < 0 ||
3107 				    status->rate_idx >= sband->n_bitrates))
3108 				goto drop;
3109 			rate = &sband->bitrates[status->rate_idx];
3110 		}
3111 	}
3112 
3113 	status->rx_flags = 0;
3114 
3115 	/*
3116 	 * key references and virtual interfaces are protected using RCU
3117 	 * and this requires that we are in a read-side RCU section during
3118 	 * receive processing
3119 	 */
3120 	rcu_read_lock();
3121 
3122 	/*
3123 	 * Frames with failed FCS/PLCP checksum are not returned,
3124 	 * all other frames are returned without radiotap header
3125 	 * if it was previously present.
3126 	 * Also, frames with less than 16 bytes are dropped.
3127 	 */
3128 	skb = ieee80211_rx_monitor(local, skb, rate);
3129 	if (!skb) {
3130 		rcu_read_unlock();
3131 		return;
3132 	}
3133 
3134 	ieee80211_tpt_led_trig_rx(local,
3135 			((struct ieee80211_hdr *)skb->data)->frame_control,
3136 			skb->len);
3137 	__ieee80211_rx_handle_packet(hw, skb);
3138 
3139 	rcu_read_unlock();
3140 
3141 	return;
3142  drop:
3143 	kfree_skb(skb);
3144 }
3145 EXPORT_SYMBOL(ieee80211_rx);
3146 
3147 /* This is a version of the rx handler that can be called from hard irq
3148  * context. Post the skb on the queue and schedule the tasklet */
3149 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3150 {
3151 	struct ieee80211_local *local = hw_to_local(hw);
3152 
3153 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3154 
3155 	skb->pkt_type = IEEE80211_RX_MSG;
3156 	skb_queue_tail(&local->skb_queue, skb);
3157 	tasklet_schedule(&local->tasklet);
3158 }
3159 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3160