xref: /linux/net/mac80211/rx.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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 
23 #include "ieee80211_i.h"
24 #include "driver-ops.h"
25 #include "led.h"
26 #include "mesh.h"
27 #include "wep.h"
28 #include "wpa.h"
29 #include "tkip.h"
30 #include "wme.h"
31 #include "rate.h"
32 
33 /*
34  * monitor mode reception
35  *
36  * This function cleans up the SKB, i.e. it removes all the stuff
37  * only useful for monitoring.
38  */
39 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
40 					   struct sk_buff *skb)
41 {
42 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
43 		if (likely(skb->len > FCS_LEN))
44 			__pskb_trim(skb, skb->len - FCS_LEN);
45 		else {
46 			/* driver bug */
47 			WARN_ON(1);
48 			dev_kfree_skb(skb);
49 			skb = NULL;
50 		}
51 	}
52 
53 	return skb;
54 }
55 
56 static inline int should_drop_frame(struct sk_buff *skb,
57 				    int present_fcs_len)
58 {
59 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
60 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
61 
62 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
63 		return 1;
64 	if (unlikely(skb->len < 16 + present_fcs_len))
65 		return 1;
66 	if (ieee80211_is_ctl(hdr->frame_control) &&
67 	    !ieee80211_is_pspoll(hdr->frame_control) &&
68 	    !ieee80211_is_back_req(hdr->frame_control))
69 		return 1;
70 	return 0;
71 }
72 
73 static int
74 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
75 			  struct ieee80211_rx_status *status)
76 {
77 	int len;
78 
79 	/* always present fields */
80 	len = sizeof(struct ieee80211_radiotap_header) + 9;
81 
82 	if (status->flag & RX_FLAG_MACTIME_MPDU)
83 		len += 8;
84 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
85 		len += 1;
86 
87 	if (len & 1) /* padding for RX_FLAGS if necessary */
88 		len++;
89 
90 	if (status->flag & RX_FLAG_HT) /* HT info */
91 		len += 3;
92 
93 	return len;
94 }
95 
96 /*
97  * ieee80211_add_rx_radiotap_header - add radiotap header
98  *
99  * add a radiotap header containing all the fields which the hardware provided.
100  */
101 static void
102 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
103 				 struct sk_buff *skb,
104 				 struct ieee80211_rate *rate,
105 				 int rtap_len)
106 {
107 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
108 	struct ieee80211_radiotap_header *rthdr;
109 	unsigned char *pos;
110 	u16 rx_flags = 0;
111 
112 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
113 	memset(rthdr, 0, rtap_len);
114 
115 	/* radiotap header, set always present flags */
116 	rthdr->it_present =
117 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
118 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
119 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
120 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
121 	rthdr->it_len = cpu_to_le16(rtap_len);
122 
123 	pos = (unsigned char *)(rthdr+1);
124 
125 	/* the order of the following fields is important */
126 
127 	/* IEEE80211_RADIOTAP_TSFT */
128 	if (status->flag & RX_FLAG_MACTIME_MPDU) {
129 		put_unaligned_le64(status->mactime, pos);
130 		rthdr->it_present |=
131 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
132 		pos += 8;
133 	}
134 
135 	/* IEEE80211_RADIOTAP_FLAGS */
136 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
137 		*pos |= IEEE80211_RADIOTAP_F_FCS;
138 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
139 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
140 	if (status->flag & RX_FLAG_SHORTPRE)
141 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
142 	pos++;
143 
144 	/* IEEE80211_RADIOTAP_RATE */
145 	if (!rate || status->flag & RX_FLAG_HT) {
146 		/*
147 		 * Without rate information don't add it. If we have,
148 		 * MCS information is a separate field in radiotap,
149 		 * added below. The byte here is needed as padding
150 		 * for the channel though, so initialise it to 0.
151 		 */
152 		*pos = 0;
153 	} else {
154 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
155 		*pos = rate->bitrate / 5;
156 	}
157 	pos++;
158 
159 	/* IEEE80211_RADIOTAP_CHANNEL */
160 	put_unaligned_le16(status->freq, pos);
161 	pos += 2;
162 	if (status->band == IEEE80211_BAND_5GHZ)
163 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
164 				   pos);
165 	else if (status->flag & RX_FLAG_HT)
166 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
167 				   pos);
168 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
169 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
170 				   pos);
171 	else if (rate)
172 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
173 				   pos);
174 	else
175 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
176 	pos += 2;
177 
178 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
179 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
180 		*pos = status->signal;
181 		rthdr->it_present |=
182 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
183 		pos++;
184 	}
185 
186 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
187 
188 	/* IEEE80211_RADIOTAP_ANTENNA */
189 	*pos = status->antenna;
190 	pos++;
191 
192 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
193 
194 	/* IEEE80211_RADIOTAP_RX_FLAGS */
195 	/* ensure 2 byte alignment for the 2 byte field as required */
196 	if ((pos - (u8 *)rthdr) & 1)
197 		pos++;
198 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
199 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
200 	put_unaligned_le16(rx_flags, pos);
201 	pos += 2;
202 
203 	if (status->flag & RX_FLAG_HT) {
204 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
205 		*pos++ = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
206 			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
207 			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
208 		*pos = 0;
209 		if (status->flag & RX_FLAG_SHORT_GI)
210 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
211 		if (status->flag & RX_FLAG_40MHZ)
212 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
213 		pos++;
214 		*pos++ = status->rate_idx;
215 	}
216 }
217 
218 /*
219  * This function copies a received frame to all monitor interfaces and
220  * returns a cleaned-up SKB that no longer includes the FCS nor the
221  * radiotap header the driver might have added.
222  */
223 static struct sk_buff *
224 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
225 		     struct ieee80211_rate *rate)
226 {
227 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
228 	struct ieee80211_sub_if_data *sdata;
229 	int needed_headroom = 0;
230 	struct sk_buff *skb, *skb2;
231 	struct net_device *prev_dev = NULL;
232 	int present_fcs_len = 0;
233 
234 	/*
235 	 * First, we may need to make a copy of the skb because
236 	 *  (1) we need to modify it for radiotap (if not present), and
237 	 *  (2) the other RX handlers will modify the skb we got.
238 	 *
239 	 * We don't need to, of course, if we aren't going to return
240 	 * the SKB because it has a bad FCS/PLCP checksum.
241 	 */
242 
243 	/* room for the radiotap header based on driver features */
244 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
245 
246 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
247 		present_fcs_len = FCS_LEN;
248 
249 	/* make sure hdr->frame_control is on the linear part */
250 	if (!pskb_may_pull(origskb, 2)) {
251 		dev_kfree_skb(origskb);
252 		return NULL;
253 	}
254 
255 	if (!local->monitors) {
256 		if (should_drop_frame(origskb, present_fcs_len)) {
257 			dev_kfree_skb(origskb);
258 			return NULL;
259 		}
260 
261 		return remove_monitor_info(local, origskb);
262 	}
263 
264 	if (should_drop_frame(origskb, present_fcs_len)) {
265 		/* only need to expand headroom if necessary */
266 		skb = origskb;
267 		origskb = NULL;
268 
269 		/*
270 		 * This shouldn't trigger often because most devices have an
271 		 * RX header they pull before we get here, and that should
272 		 * be big enough for our radiotap information. We should
273 		 * probably export the length to drivers so that we can have
274 		 * them allocate enough headroom to start with.
275 		 */
276 		if (skb_headroom(skb) < needed_headroom &&
277 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
278 			dev_kfree_skb(skb);
279 			return NULL;
280 		}
281 	} else {
282 		/*
283 		 * Need to make a copy and possibly remove radiotap header
284 		 * and FCS from the original.
285 		 */
286 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
287 
288 		origskb = remove_monitor_info(local, origskb);
289 
290 		if (!skb)
291 			return origskb;
292 	}
293 
294 	/* prepend radiotap information */
295 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
296 
297 	skb_reset_mac_header(skb);
298 	skb->ip_summed = CHECKSUM_UNNECESSARY;
299 	skb->pkt_type = PACKET_OTHERHOST;
300 	skb->protocol = htons(ETH_P_802_2);
301 
302 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
303 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
304 			continue;
305 
306 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
307 			continue;
308 
309 		if (!ieee80211_sdata_running(sdata))
310 			continue;
311 
312 		if (prev_dev) {
313 			skb2 = skb_clone(skb, GFP_ATOMIC);
314 			if (skb2) {
315 				skb2->dev = prev_dev;
316 				netif_receive_skb(skb2);
317 			}
318 		}
319 
320 		prev_dev = sdata->dev;
321 		sdata->dev->stats.rx_packets++;
322 		sdata->dev->stats.rx_bytes += skb->len;
323 	}
324 
325 	if (prev_dev) {
326 		skb->dev = prev_dev;
327 		netif_receive_skb(skb);
328 	} else
329 		dev_kfree_skb(skb);
330 
331 	return origskb;
332 }
333 
334 
335 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
336 {
337 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
338 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
339 	int tid, seqno_idx, security_idx;
340 
341 	/* does the frame have a qos control field? */
342 	if (ieee80211_is_data_qos(hdr->frame_control)) {
343 		u8 *qc = ieee80211_get_qos_ctl(hdr);
344 		/* frame has qos control */
345 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
346 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
347 			status->rx_flags |= IEEE80211_RX_AMSDU;
348 
349 		seqno_idx = tid;
350 		security_idx = tid;
351 	} else {
352 		/*
353 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
354 		 *
355 		 *	Sequence numbers for management frames, QoS data
356 		 *	frames with a broadcast/multicast address in the
357 		 *	Address 1 field, and all non-QoS data frames sent
358 		 *	by QoS STAs are assigned using an additional single
359 		 *	modulo-4096 counter, [...]
360 		 *
361 		 * We also use that counter for non-QoS STAs.
362 		 */
363 		seqno_idx = NUM_RX_DATA_QUEUES;
364 		security_idx = 0;
365 		if (ieee80211_is_mgmt(hdr->frame_control))
366 			security_idx = NUM_RX_DATA_QUEUES;
367 		tid = 0;
368 	}
369 
370 	rx->seqno_idx = seqno_idx;
371 	rx->security_idx = security_idx;
372 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
373 	 * For now, set skb->priority to 0 for other cases. */
374 	rx->skb->priority = (tid > 7) ? 0 : tid;
375 }
376 
377 /**
378  * DOC: Packet alignment
379  *
380  * Drivers always need to pass packets that are aligned to two-byte boundaries
381  * to the stack.
382  *
383  * Additionally, should, if possible, align the payload data in a way that
384  * guarantees that the contained IP header is aligned to a four-byte
385  * boundary. In the case of regular frames, this simply means aligning the
386  * payload to a four-byte boundary (because either the IP header is directly
387  * contained, or IV/RFC1042 headers that have a length divisible by four are
388  * in front of it).  If the payload data is not properly aligned and the
389  * architecture doesn't support efficient unaligned operations, mac80211
390  * will align the data.
391  *
392  * With A-MSDU frames, however, the payload data address must yield two modulo
393  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
394  * push the IP header further back to a multiple of four again. Thankfully, the
395  * specs were sane enough this time around to require padding each A-MSDU
396  * subframe to a length that is a multiple of four.
397  *
398  * Padding like Atheros hardware adds which is between the 802.11 header and
399  * the payload is not supported, the driver is required to move the 802.11
400  * header to be directly in front of the payload in that case.
401  */
402 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
403 {
404 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
405 	WARN_ONCE((unsigned long)rx->skb->data & 1,
406 		  "unaligned packet at 0x%p\n", rx->skb->data);
407 #endif
408 }
409 
410 
411 /* rx handlers */
412 
413 static ieee80211_rx_result debug_noinline
414 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
415 {
416 	struct ieee80211_local *local = rx->local;
417 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
418 	struct sk_buff *skb = rx->skb;
419 
420 	if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
421 		   !local->sched_scanning))
422 		return RX_CONTINUE;
423 
424 	if (test_bit(SCAN_HW_SCANNING, &local->scanning) ||
425 	    test_bit(SCAN_SW_SCANNING, &local->scanning) ||
426 	    local->sched_scanning)
427 		return ieee80211_scan_rx(rx->sdata, skb);
428 
429 	/* scanning finished during invoking of handlers */
430 	I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
431 	return RX_DROP_UNUSABLE;
432 }
433 
434 
435 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
436 {
437 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
438 
439 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
440 		return 0;
441 
442 	return ieee80211_is_robust_mgmt_frame(hdr);
443 }
444 
445 
446 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
447 {
448 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
449 
450 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
451 		return 0;
452 
453 	return ieee80211_is_robust_mgmt_frame(hdr);
454 }
455 
456 
457 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
458 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
459 {
460 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
461 	struct ieee80211_mmie *mmie;
462 
463 	if (skb->len < 24 + sizeof(*mmie) ||
464 	    !is_multicast_ether_addr(hdr->da))
465 		return -1;
466 
467 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
468 		return -1; /* not a robust management frame */
469 
470 	mmie = (struct ieee80211_mmie *)
471 		(skb->data + skb->len - sizeof(*mmie));
472 	if (mmie->element_id != WLAN_EID_MMIE ||
473 	    mmie->length != sizeof(*mmie) - 2)
474 		return -1;
475 
476 	return le16_to_cpu(mmie->key_id);
477 }
478 
479 
480 static ieee80211_rx_result
481 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
482 {
483 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
484 	char *dev_addr = rx->sdata->vif.addr;
485 
486 	if (ieee80211_is_data(hdr->frame_control)) {
487 		if (is_multicast_ether_addr(hdr->addr1)) {
488 			if (ieee80211_has_tods(hdr->frame_control) ||
489 				!ieee80211_has_fromds(hdr->frame_control))
490 				return RX_DROP_MONITOR;
491 			if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
492 				return RX_DROP_MONITOR;
493 		} else {
494 			if (!ieee80211_has_a4(hdr->frame_control))
495 				return RX_DROP_MONITOR;
496 			if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
497 				return RX_DROP_MONITOR;
498 		}
499 	}
500 
501 	/* If there is not an established peer link and this is not a peer link
502 	 * establisment frame, beacon or probe, drop the frame.
503 	 */
504 
505 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
506 		struct ieee80211_mgmt *mgmt;
507 
508 		if (!ieee80211_is_mgmt(hdr->frame_control))
509 			return RX_DROP_MONITOR;
510 
511 		if (ieee80211_is_action(hdr->frame_control)) {
512 			u8 category;
513 			mgmt = (struct ieee80211_mgmt *)hdr;
514 			category = mgmt->u.action.category;
515 			if (category != WLAN_CATEGORY_MESH_ACTION &&
516 				category != WLAN_CATEGORY_SELF_PROTECTED)
517 				return RX_DROP_MONITOR;
518 			return RX_CONTINUE;
519 		}
520 
521 		if (ieee80211_is_probe_req(hdr->frame_control) ||
522 		    ieee80211_is_probe_resp(hdr->frame_control) ||
523 		    ieee80211_is_beacon(hdr->frame_control) ||
524 		    ieee80211_is_auth(hdr->frame_control))
525 			return RX_CONTINUE;
526 
527 		return RX_DROP_MONITOR;
528 
529 	}
530 
531 	return RX_CONTINUE;
532 }
533 
534 #define SEQ_MODULO 0x1000
535 #define SEQ_MASK   0xfff
536 
537 static inline int seq_less(u16 sq1, u16 sq2)
538 {
539 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
540 }
541 
542 static inline u16 seq_inc(u16 sq)
543 {
544 	return (sq + 1) & SEQ_MASK;
545 }
546 
547 static inline u16 seq_sub(u16 sq1, u16 sq2)
548 {
549 	return (sq1 - sq2) & SEQ_MASK;
550 }
551 
552 
553 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
554 					    struct tid_ampdu_rx *tid_agg_rx,
555 					    int index)
556 {
557 	struct ieee80211_local *local = hw_to_local(hw);
558 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
559 	struct ieee80211_rx_status *status;
560 
561 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
562 
563 	if (!skb)
564 		goto no_frame;
565 
566 	/* release the frame from the reorder ring buffer */
567 	tid_agg_rx->stored_mpdu_num--;
568 	tid_agg_rx->reorder_buf[index] = NULL;
569 	status = IEEE80211_SKB_RXCB(skb);
570 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
571 	skb_queue_tail(&local->rx_skb_queue, skb);
572 
573 no_frame:
574 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
575 }
576 
577 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
578 					     struct tid_ampdu_rx *tid_agg_rx,
579 					     u16 head_seq_num)
580 {
581 	int index;
582 
583 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
584 
585 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
586 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
587 							tid_agg_rx->buf_size;
588 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
589 	}
590 }
591 
592 /*
593  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
594  * the skb was added to the buffer longer than this time ago, the earlier
595  * frames that have not yet been received are assumed to be lost and the skb
596  * can be released for processing. This may also release other skb's from the
597  * reorder buffer if there are no additional gaps between the frames.
598  *
599  * Callers must hold tid_agg_rx->reorder_lock.
600  */
601 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
602 
603 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
604 					  struct tid_ampdu_rx *tid_agg_rx)
605 {
606 	int index, j;
607 
608 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
609 
610 	/* release the buffer until next missing frame */
611 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
612 						tid_agg_rx->buf_size;
613 	if (!tid_agg_rx->reorder_buf[index] &&
614 	    tid_agg_rx->stored_mpdu_num > 1) {
615 		/*
616 		 * No buffers ready to be released, but check whether any
617 		 * frames in the reorder buffer have timed out.
618 		 */
619 		int skipped = 1;
620 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
621 		     j = (j + 1) % tid_agg_rx->buf_size) {
622 			if (!tid_agg_rx->reorder_buf[j]) {
623 				skipped++;
624 				continue;
625 			}
626 			if (skipped &&
627 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
628 					HT_RX_REORDER_BUF_TIMEOUT))
629 				goto set_release_timer;
630 
631 #ifdef CONFIG_MAC80211_HT_DEBUG
632 			if (net_ratelimit())
633 				wiphy_debug(hw->wiphy,
634 					    "release an RX reorder frame due to timeout on earlier frames\n");
635 #endif
636 			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
637 
638 			/*
639 			 * Increment the head seq# also for the skipped slots.
640 			 */
641 			tid_agg_rx->head_seq_num =
642 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
643 			skipped = 0;
644 		}
645 	} else while (tid_agg_rx->reorder_buf[index]) {
646 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
647 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
648 							tid_agg_rx->buf_size;
649 	}
650 
651 	if (tid_agg_rx->stored_mpdu_num) {
652 		j = index = seq_sub(tid_agg_rx->head_seq_num,
653 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
654 
655 		for (; j != (index - 1) % tid_agg_rx->buf_size;
656 		     j = (j + 1) % tid_agg_rx->buf_size) {
657 			if (tid_agg_rx->reorder_buf[j])
658 				break;
659 		}
660 
661  set_release_timer:
662 
663 		mod_timer(&tid_agg_rx->reorder_timer,
664 			  tid_agg_rx->reorder_time[j] + 1 +
665 			  HT_RX_REORDER_BUF_TIMEOUT);
666 	} else {
667 		del_timer(&tid_agg_rx->reorder_timer);
668 	}
669 }
670 
671 /*
672  * As this function belongs to the RX path it must be under
673  * rcu_read_lock protection. It returns false if the frame
674  * can be processed immediately, true if it was consumed.
675  */
676 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
677 					     struct tid_ampdu_rx *tid_agg_rx,
678 					     struct sk_buff *skb)
679 {
680 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
681 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
682 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
683 	u16 head_seq_num, buf_size;
684 	int index;
685 	bool ret = true;
686 
687 	spin_lock(&tid_agg_rx->reorder_lock);
688 
689 	buf_size = tid_agg_rx->buf_size;
690 	head_seq_num = tid_agg_rx->head_seq_num;
691 
692 	/* frame with out of date sequence number */
693 	if (seq_less(mpdu_seq_num, head_seq_num)) {
694 		dev_kfree_skb(skb);
695 		goto out;
696 	}
697 
698 	/*
699 	 * If frame the sequence number exceeds our buffering window
700 	 * size release some previous frames to make room for this one.
701 	 */
702 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
703 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
704 		/* release stored frames up to new head to stack */
705 		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
706 	}
707 
708 	/* Now the new frame is always in the range of the reordering buffer */
709 
710 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
711 
712 	/* check if we already stored this frame */
713 	if (tid_agg_rx->reorder_buf[index]) {
714 		dev_kfree_skb(skb);
715 		goto out;
716 	}
717 
718 	/*
719 	 * If the current MPDU is in the right order and nothing else
720 	 * is stored we can process it directly, no need to buffer it.
721 	 * If it is first but there's something stored, we may be able
722 	 * to release frames after this one.
723 	 */
724 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
725 	    tid_agg_rx->stored_mpdu_num == 0) {
726 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
727 		ret = false;
728 		goto out;
729 	}
730 
731 	/* put the frame in the reordering buffer */
732 	tid_agg_rx->reorder_buf[index] = skb;
733 	tid_agg_rx->reorder_time[index] = jiffies;
734 	tid_agg_rx->stored_mpdu_num++;
735 	ieee80211_sta_reorder_release(hw, tid_agg_rx);
736 
737  out:
738 	spin_unlock(&tid_agg_rx->reorder_lock);
739 	return ret;
740 }
741 
742 /*
743  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
744  * true if the MPDU was buffered, false if it should be processed.
745  */
746 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
747 {
748 	struct sk_buff *skb = rx->skb;
749 	struct ieee80211_local *local = rx->local;
750 	struct ieee80211_hw *hw = &local->hw;
751 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
752 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
753 	struct sta_info *sta = rx->sta;
754 	struct tid_ampdu_rx *tid_agg_rx;
755 	u16 sc;
756 	u8 tid, ack_policy;
757 
758 	if (!ieee80211_is_data_qos(hdr->frame_control))
759 		goto dont_reorder;
760 
761 	/*
762 	 * filter the QoS data rx stream according to
763 	 * STA/TID and check if this STA/TID is on aggregation
764 	 */
765 
766 	if (!sta)
767 		goto dont_reorder;
768 
769 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
770 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
771 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
772 
773 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
774 	if (!tid_agg_rx)
775 		goto dont_reorder;
776 
777 	/* qos null data frames are excluded */
778 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
779 		goto dont_reorder;
780 
781 	/* not part of a BA session */
782 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
783 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
784 		goto dont_reorder;
785 
786 	/* not actually part of this BA session */
787 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
788 		goto dont_reorder;
789 
790 	/* new, potentially un-ordered, ampdu frame - process it */
791 
792 	/* reset session timer */
793 	if (tid_agg_rx->timeout)
794 		mod_timer(&tid_agg_rx->session_timer,
795 			  TU_TO_EXP_TIME(tid_agg_rx->timeout));
796 
797 	/* if this mpdu is fragmented - terminate rx aggregation session */
798 	sc = le16_to_cpu(hdr->seq_ctrl);
799 	if (sc & IEEE80211_SCTL_FRAG) {
800 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
801 		skb_queue_tail(&rx->sdata->skb_queue, skb);
802 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
803 		return;
804 	}
805 
806 	/*
807 	 * No locking needed -- we will only ever process one
808 	 * RX packet at a time, and thus own tid_agg_rx. All
809 	 * other code manipulating it needs to (and does) make
810 	 * sure that we cannot get to it any more before doing
811 	 * anything with it.
812 	 */
813 	if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
814 		return;
815 
816  dont_reorder:
817 	skb_queue_tail(&local->rx_skb_queue, skb);
818 }
819 
820 static ieee80211_rx_result debug_noinline
821 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
822 {
823 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
824 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
825 
826 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
827 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
828 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
829 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
830 			     hdr->seq_ctrl)) {
831 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
832 				rx->local->dot11FrameDuplicateCount++;
833 				rx->sta->num_duplicates++;
834 			}
835 			return RX_DROP_UNUSABLE;
836 		} else
837 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
838 	}
839 
840 	if (unlikely(rx->skb->len < 16)) {
841 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
842 		return RX_DROP_MONITOR;
843 	}
844 
845 	/* Drop disallowed frame classes based on STA auth/assoc state;
846 	 * IEEE 802.11, Chap 5.5.
847 	 *
848 	 * mac80211 filters only based on association state, i.e. it drops
849 	 * Class 3 frames from not associated stations. hostapd sends
850 	 * deauth/disassoc frames when needed. In addition, hostapd is
851 	 * responsible for filtering on both auth and assoc states.
852 	 */
853 
854 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
855 		return ieee80211_rx_mesh_check(rx);
856 
857 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
858 		      ieee80211_is_pspoll(hdr->frame_control)) &&
859 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
860 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
861 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
862 		if (rx->sta && rx->sta->dummy &&
863 		    ieee80211_is_data_present(hdr->frame_control)) {
864 			u16 ethertype;
865 			u8 *payload;
866 
867 			payload = rx->skb->data +
868 				ieee80211_hdrlen(hdr->frame_control);
869 			ethertype = (payload[6] << 8) | payload[7];
870 			if (cpu_to_be16(ethertype) ==
871 			    rx->sdata->control_port_protocol)
872 				return RX_CONTINUE;
873 		}
874 
875 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
876 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
877 					       hdr->addr2,
878 					       GFP_ATOMIC))
879 			return RX_DROP_UNUSABLE;
880 
881 		return RX_DROP_MONITOR;
882 	}
883 
884 	return RX_CONTINUE;
885 }
886 
887 
888 static ieee80211_rx_result debug_noinline
889 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
890 {
891 	struct sk_buff *skb = rx->skb;
892 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
893 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
894 	int keyidx;
895 	int hdrlen;
896 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
897 	struct ieee80211_key *sta_ptk = NULL;
898 	int mmie_keyidx = -1;
899 	__le16 fc;
900 
901 	/*
902 	 * Key selection 101
903 	 *
904 	 * There are four types of keys:
905 	 *  - GTK (group keys)
906 	 *  - IGTK (group keys for management frames)
907 	 *  - PTK (pairwise keys)
908 	 *  - STK (station-to-station pairwise keys)
909 	 *
910 	 * When selecting a key, we have to distinguish between multicast
911 	 * (including broadcast) and unicast frames, the latter can only
912 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
913 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
914 	 * unicast frames can also use key indices like GTKs. Hence, if we
915 	 * don't have a PTK/STK we check the key index for a WEP key.
916 	 *
917 	 * Note that in a regular BSS, multicast frames are sent by the
918 	 * AP only, associated stations unicast the frame to the AP first
919 	 * which then multicasts it on their behalf.
920 	 *
921 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
922 	 * with each station, that is something we don't currently handle.
923 	 * The spec seems to expect that one negotiates the same key with
924 	 * every station but there's no such requirement; VLANs could be
925 	 * possible.
926 	 */
927 
928 	/*
929 	 * No point in finding a key and decrypting if the frame is neither
930 	 * addressed to us nor a multicast frame.
931 	 */
932 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
933 		return RX_CONTINUE;
934 
935 	/* start without a key */
936 	rx->key = NULL;
937 
938 	if (rx->sta)
939 		sta_ptk = rcu_dereference(rx->sta->ptk);
940 
941 	fc = hdr->frame_control;
942 
943 	if (!ieee80211_has_protected(fc))
944 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
945 
946 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
947 		rx->key = sta_ptk;
948 		if ((status->flag & RX_FLAG_DECRYPTED) &&
949 		    (status->flag & RX_FLAG_IV_STRIPPED))
950 			return RX_CONTINUE;
951 		/* Skip decryption if the frame is not protected. */
952 		if (!ieee80211_has_protected(fc))
953 			return RX_CONTINUE;
954 	} else if (mmie_keyidx >= 0) {
955 		/* Broadcast/multicast robust management frame / BIP */
956 		if ((status->flag & RX_FLAG_DECRYPTED) &&
957 		    (status->flag & RX_FLAG_IV_STRIPPED))
958 			return RX_CONTINUE;
959 
960 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
961 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
962 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
963 		if (rx->sta)
964 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
965 		if (!rx->key)
966 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
967 	} else if (!ieee80211_has_protected(fc)) {
968 		/*
969 		 * The frame was not protected, so skip decryption. However, we
970 		 * need to set rx->key if there is a key that could have been
971 		 * used so that the frame may be dropped if encryption would
972 		 * have been expected.
973 		 */
974 		struct ieee80211_key *key = NULL;
975 		struct ieee80211_sub_if_data *sdata = rx->sdata;
976 		int i;
977 
978 		if (ieee80211_is_mgmt(fc) &&
979 		    is_multicast_ether_addr(hdr->addr1) &&
980 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
981 			rx->key = key;
982 		else {
983 			if (rx->sta) {
984 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
985 					key = rcu_dereference(rx->sta->gtk[i]);
986 					if (key)
987 						break;
988 				}
989 			}
990 			if (!key) {
991 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
992 					key = rcu_dereference(sdata->keys[i]);
993 					if (key)
994 						break;
995 				}
996 			}
997 			if (key)
998 				rx->key = key;
999 		}
1000 		return RX_CONTINUE;
1001 	} else {
1002 		u8 keyid;
1003 		/*
1004 		 * The device doesn't give us the IV so we won't be
1005 		 * able to look up the key. That's ok though, we
1006 		 * don't need to decrypt the frame, we just won't
1007 		 * be able to keep statistics accurate.
1008 		 * Except for key threshold notifications, should
1009 		 * we somehow allow the driver to tell us which key
1010 		 * the hardware used if this flag is set?
1011 		 */
1012 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1013 		    (status->flag & RX_FLAG_IV_STRIPPED))
1014 			return RX_CONTINUE;
1015 
1016 		hdrlen = ieee80211_hdrlen(fc);
1017 
1018 		if (rx->skb->len < 8 + hdrlen)
1019 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1020 
1021 		/*
1022 		 * no need to call ieee80211_wep_get_keyidx,
1023 		 * it verifies a bunch of things we've done already
1024 		 */
1025 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1026 		keyidx = keyid >> 6;
1027 
1028 		/* check per-station GTK first, if multicast packet */
1029 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1030 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1031 
1032 		/* if not found, try default key */
1033 		if (!rx->key) {
1034 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1035 
1036 			/*
1037 			 * RSNA-protected unicast frames should always be
1038 			 * sent with pairwise or station-to-station keys,
1039 			 * but for WEP we allow using a key index as well.
1040 			 */
1041 			if (rx->key &&
1042 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1043 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1044 			    !is_multicast_ether_addr(hdr->addr1))
1045 				rx->key = NULL;
1046 		}
1047 	}
1048 
1049 	if (rx->key) {
1050 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1051 			return RX_DROP_MONITOR;
1052 
1053 		rx->key->tx_rx_count++;
1054 		/* TODO: add threshold stuff again */
1055 	} else {
1056 		return RX_DROP_MONITOR;
1057 	}
1058 
1059 	if (skb_linearize(rx->skb))
1060 		return RX_DROP_UNUSABLE;
1061 	/* the hdr variable is invalid now! */
1062 
1063 	switch (rx->key->conf.cipher) {
1064 	case WLAN_CIPHER_SUITE_WEP40:
1065 	case WLAN_CIPHER_SUITE_WEP104:
1066 		/* Check for weak IVs if possible */
1067 		if (rx->sta && ieee80211_is_data(fc) &&
1068 		    (!(status->flag & RX_FLAG_IV_STRIPPED) ||
1069 		     !(status->flag & RX_FLAG_DECRYPTED)) &&
1070 		    ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1071 			rx->sta->wep_weak_iv_count++;
1072 
1073 		result = ieee80211_crypto_wep_decrypt(rx);
1074 		break;
1075 	case WLAN_CIPHER_SUITE_TKIP:
1076 		result = ieee80211_crypto_tkip_decrypt(rx);
1077 		break;
1078 	case WLAN_CIPHER_SUITE_CCMP:
1079 		result = ieee80211_crypto_ccmp_decrypt(rx);
1080 		break;
1081 	case WLAN_CIPHER_SUITE_AES_CMAC:
1082 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1083 		break;
1084 	default:
1085 		/*
1086 		 * We can reach here only with HW-only algorithms
1087 		 * but why didn't it decrypt the frame?!
1088 		 */
1089 		return RX_DROP_UNUSABLE;
1090 	}
1091 
1092 	/* either the frame has been decrypted or will be dropped */
1093 	status->flag |= RX_FLAG_DECRYPTED;
1094 
1095 	return result;
1096 }
1097 
1098 static ieee80211_rx_result debug_noinline
1099 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1100 {
1101 	struct ieee80211_local *local;
1102 	struct ieee80211_hdr *hdr;
1103 	struct sk_buff *skb;
1104 
1105 	local = rx->local;
1106 	skb = rx->skb;
1107 	hdr = (struct ieee80211_hdr *) skb->data;
1108 
1109 	if (!local->pspolling)
1110 		return RX_CONTINUE;
1111 
1112 	if (!ieee80211_has_fromds(hdr->frame_control))
1113 		/* this is not from AP */
1114 		return RX_CONTINUE;
1115 
1116 	if (!ieee80211_is_data(hdr->frame_control))
1117 		return RX_CONTINUE;
1118 
1119 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1120 		/* AP has no more frames buffered for us */
1121 		local->pspolling = false;
1122 		return RX_CONTINUE;
1123 	}
1124 
1125 	/* more data bit is set, let's request a new frame from the AP */
1126 	ieee80211_send_pspoll(local, rx->sdata);
1127 
1128 	return RX_CONTINUE;
1129 }
1130 
1131 static void ap_sta_ps_start(struct sta_info *sta)
1132 {
1133 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1134 	struct ieee80211_local *local = sdata->local;
1135 
1136 	atomic_inc(&sdata->bss->num_sta_ps);
1137 	set_sta_flag(sta, WLAN_STA_PS_STA);
1138 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1139 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1140 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1141 	printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1142 	       sdata->name, sta->sta.addr, sta->sta.aid);
1143 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1144 }
1145 
1146 static void ap_sta_ps_end(struct sta_info *sta)
1147 {
1148 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1149 
1150 	atomic_dec(&sdata->bss->num_sta_ps);
1151 
1152 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1153 	printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1154 	       sdata->name, sta->sta.addr, sta->sta.aid);
1155 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1156 
1157 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1158 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1159 		printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1160 		       sdata->name, sta->sta.addr, sta->sta.aid);
1161 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1162 		return;
1163 	}
1164 
1165 	ieee80211_sta_ps_deliver_wakeup(sta);
1166 }
1167 
1168 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1169 {
1170 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1171 	bool in_ps;
1172 
1173 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1174 
1175 	/* Don't let the same PS state be set twice */
1176 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1177 	if ((start && in_ps) || (!start && !in_ps))
1178 		return -EINVAL;
1179 
1180 	if (start)
1181 		ap_sta_ps_start(sta_inf);
1182 	else
1183 		ap_sta_ps_end(sta_inf);
1184 
1185 	return 0;
1186 }
1187 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1188 
1189 static ieee80211_rx_result debug_noinline
1190 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1191 {
1192 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1193 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1194 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1195 	int tid, ac;
1196 
1197 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1198 		return RX_CONTINUE;
1199 
1200 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1201 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1202 		return RX_CONTINUE;
1203 
1204 	/*
1205 	 * The device handles station powersave, so don't do anything about
1206 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1207 	 * it to mac80211 since they're handled.)
1208 	 */
1209 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1210 		return RX_CONTINUE;
1211 
1212 	/*
1213 	 * Don't do anything if the station isn't already asleep. In
1214 	 * the uAPSD case, the station will probably be marked asleep,
1215 	 * in the PS-Poll case the station must be confused ...
1216 	 */
1217 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1218 		return RX_CONTINUE;
1219 
1220 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1221 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1222 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1223 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1224 			else
1225 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1226 		}
1227 
1228 		/* Free PS Poll skb here instead of returning RX_DROP that would
1229 		 * count as an dropped frame. */
1230 		dev_kfree_skb(rx->skb);
1231 
1232 		return RX_QUEUED;
1233 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1234 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1235 		   ieee80211_has_pm(hdr->frame_control) &&
1236 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1237 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1238 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1239 		ac = ieee802_1d_to_ac[tid & 7];
1240 
1241 		/*
1242 		 * If this AC is not trigger-enabled do nothing.
1243 		 *
1244 		 * NB: This could/should check a separate bitmap of trigger-
1245 		 * enabled queues, but for now we only implement uAPSD w/o
1246 		 * TSPEC changes to the ACs, so they're always the same.
1247 		 */
1248 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1249 			return RX_CONTINUE;
1250 
1251 		/* if we are in a service period, do nothing */
1252 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1253 			return RX_CONTINUE;
1254 
1255 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1256 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1257 		else
1258 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1259 	}
1260 
1261 	return RX_CONTINUE;
1262 }
1263 
1264 static ieee80211_rx_result debug_noinline
1265 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1266 {
1267 	struct sta_info *sta = rx->sta;
1268 	struct sk_buff *skb = rx->skb;
1269 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1270 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1271 
1272 	if (!sta)
1273 		return RX_CONTINUE;
1274 
1275 	/*
1276 	 * Update last_rx only for IBSS packets which are for the current
1277 	 * BSSID to avoid keeping the current IBSS network alive in cases
1278 	 * where other STAs start using different BSSID.
1279 	 */
1280 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1281 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1282 						NL80211_IFTYPE_ADHOC);
1283 		if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) {
1284 			sta->last_rx = jiffies;
1285 			if (ieee80211_is_data(hdr->frame_control)) {
1286 				sta->last_rx_rate_idx = status->rate_idx;
1287 				sta->last_rx_rate_flag = status->flag;
1288 			}
1289 		}
1290 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1291 		/*
1292 		 * Mesh beacons will update last_rx when if they are found to
1293 		 * match the current local configuration when processed.
1294 		 */
1295 		sta->last_rx = jiffies;
1296 		if (ieee80211_is_data(hdr->frame_control)) {
1297 			sta->last_rx_rate_idx = status->rate_idx;
1298 			sta->last_rx_rate_flag = status->flag;
1299 		}
1300 	}
1301 
1302 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1303 		return RX_CONTINUE;
1304 
1305 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1306 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1307 
1308 	sta->rx_fragments++;
1309 	sta->rx_bytes += rx->skb->len;
1310 	sta->last_signal = status->signal;
1311 	ewma_add(&sta->avg_signal, -status->signal);
1312 
1313 	/*
1314 	 * Change STA power saving mode only at the end of a frame
1315 	 * exchange sequence.
1316 	 */
1317 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1318 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1319 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1320 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1321 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1322 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1323 			/*
1324 			 * Ignore doze->wake transitions that are
1325 			 * indicated by non-data frames, the standard
1326 			 * is unclear here, but for example going to
1327 			 * PS mode and then scanning would cause a
1328 			 * doze->wake transition for the probe request,
1329 			 * and that is clearly undesirable.
1330 			 */
1331 			if (ieee80211_is_data(hdr->frame_control) &&
1332 			    !ieee80211_has_pm(hdr->frame_control))
1333 				ap_sta_ps_end(sta);
1334 		} else {
1335 			if (ieee80211_has_pm(hdr->frame_control))
1336 				ap_sta_ps_start(sta);
1337 		}
1338 	}
1339 
1340 	/*
1341 	 * Drop (qos-)data::nullfunc frames silently, since they
1342 	 * are used only to control station power saving mode.
1343 	 */
1344 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1345 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1346 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1347 
1348 		/*
1349 		 * If we receive a 4-addr nullfunc frame from a STA
1350 		 * that was not moved to a 4-addr STA vlan yet send
1351 		 * the event to userspace and for older hostapd drop
1352 		 * the frame to the monitor interface.
1353 		 */
1354 		if (ieee80211_has_a4(hdr->frame_control) &&
1355 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1356 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1357 		      !rx->sdata->u.vlan.sta))) {
1358 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1359 				cfg80211_rx_unexpected_4addr_frame(
1360 					rx->sdata->dev, sta->sta.addr,
1361 					GFP_ATOMIC);
1362 			return RX_DROP_MONITOR;
1363 		}
1364 		/*
1365 		 * Update counter and free packet here to avoid
1366 		 * counting this as a dropped packed.
1367 		 */
1368 		sta->rx_packets++;
1369 		dev_kfree_skb(rx->skb);
1370 		return RX_QUEUED;
1371 	}
1372 
1373 	return RX_CONTINUE;
1374 } /* ieee80211_rx_h_sta_process */
1375 
1376 static inline struct ieee80211_fragment_entry *
1377 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1378 			 unsigned int frag, unsigned int seq, int rx_queue,
1379 			 struct sk_buff **skb)
1380 {
1381 	struct ieee80211_fragment_entry *entry;
1382 	int idx;
1383 
1384 	idx = sdata->fragment_next;
1385 	entry = &sdata->fragments[sdata->fragment_next++];
1386 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1387 		sdata->fragment_next = 0;
1388 
1389 	if (!skb_queue_empty(&entry->skb_list)) {
1390 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1391 		struct ieee80211_hdr *hdr =
1392 			(struct ieee80211_hdr *) entry->skb_list.next->data;
1393 		printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1394 		       "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1395 		       "addr1=%pM addr2=%pM\n",
1396 		       sdata->name, idx,
1397 		       jiffies - entry->first_frag_time, entry->seq,
1398 		       entry->last_frag, hdr->addr1, hdr->addr2);
1399 #endif
1400 		__skb_queue_purge(&entry->skb_list);
1401 	}
1402 
1403 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1404 	*skb = NULL;
1405 	entry->first_frag_time = jiffies;
1406 	entry->seq = seq;
1407 	entry->rx_queue = rx_queue;
1408 	entry->last_frag = frag;
1409 	entry->ccmp = 0;
1410 	entry->extra_len = 0;
1411 
1412 	return entry;
1413 }
1414 
1415 static inline struct ieee80211_fragment_entry *
1416 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1417 			  unsigned int frag, unsigned int seq,
1418 			  int rx_queue, struct ieee80211_hdr *hdr)
1419 {
1420 	struct ieee80211_fragment_entry *entry;
1421 	int i, idx;
1422 
1423 	idx = sdata->fragment_next;
1424 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1425 		struct ieee80211_hdr *f_hdr;
1426 
1427 		idx--;
1428 		if (idx < 0)
1429 			idx = IEEE80211_FRAGMENT_MAX - 1;
1430 
1431 		entry = &sdata->fragments[idx];
1432 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1433 		    entry->rx_queue != rx_queue ||
1434 		    entry->last_frag + 1 != frag)
1435 			continue;
1436 
1437 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1438 
1439 		/*
1440 		 * Check ftype and addresses are equal, else check next fragment
1441 		 */
1442 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1443 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1444 		    compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1445 		    compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1446 			continue;
1447 
1448 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1449 			__skb_queue_purge(&entry->skb_list);
1450 			continue;
1451 		}
1452 		return entry;
1453 	}
1454 
1455 	return NULL;
1456 }
1457 
1458 static ieee80211_rx_result debug_noinline
1459 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1460 {
1461 	struct ieee80211_hdr *hdr;
1462 	u16 sc;
1463 	__le16 fc;
1464 	unsigned int frag, seq;
1465 	struct ieee80211_fragment_entry *entry;
1466 	struct sk_buff *skb;
1467 	struct ieee80211_rx_status *status;
1468 
1469 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1470 	fc = hdr->frame_control;
1471 	sc = le16_to_cpu(hdr->seq_ctrl);
1472 	frag = sc & IEEE80211_SCTL_FRAG;
1473 
1474 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1475 		   (rx->skb)->len < 24 ||
1476 		   is_multicast_ether_addr(hdr->addr1))) {
1477 		/* not fragmented */
1478 		goto out;
1479 	}
1480 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1481 
1482 	if (skb_linearize(rx->skb))
1483 		return RX_DROP_UNUSABLE;
1484 
1485 	/*
1486 	 *  skb_linearize() might change the skb->data and
1487 	 *  previously cached variables (in this case, hdr) need to
1488 	 *  be refreshed with the new data.
1489 	 */
1490 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1491 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1492 
1493 	if (frag == 0) {
1494 		/* This is the first fragment of a new frame. */
1495 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1496 						 rx->seqno_idx, &(rx->skb));
1497 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1498 		    ieee80211_has_protected(fc)) {
1499 			int queue = rx->security_idx;
1500 			/* Store CCMP PN so that we can verify that the next
1501 			 * fragment has a sequential PN value. */
1502 			entry->ccmp = 1;
1503 			memcpy(entry->last_pn,
1504 			       rx->key->u.ccmp.rx_pn[queue],
1505 			       CCMP_PN_LEN);
1506 		}
1507 		return RX_QUEUED;
1508 	}
1509 
1510 	/* This is a fragment for a frame that should already be pending in
1511 	 * fragment cache. Add this fragment to the end of the pending entry.
1512 	 */
1513 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1514 					  rx->seqno_idx, hdr);
1515 	if (!entry) {
1516 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1517 		return RX_DROP_MONITOR;
1518 	}
1519 
1520 	/* Verify that MPDUs within one MSDU have sequential PN values.
1521 	 * (IEEE 802.11i, 8.3.3.4.5) */
1522 	if (entry->ccmp) {
1523 		int i;
1524 		u8 pn[CCMP_PN_LEN], *rpn;
1525 		int queue;
1526 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1527 			return RX_DROP_UNUSABLE;
1528 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1529 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1530 			pn[i]++;
1531 			if (pn[i])
1532 				break;
1533 		}
1534 		queue = rx->security_idx;
1535 		rpn = rx->key->u.ccmp.rx_pn[queue];
1536 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1537 			return RX_DROP_UNUSABLE;
1538 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1539 	}
1540 
1541 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1542 	__skb_queue_tail(&entry->skb_list, rx->skb);
1543 	entry->last_frag = frag;
1544 	entry->extra_len += rx->skb->len;
1545 	if (ieee80211_has_morefrags(fc)) {
1546 		rx->skb = NULL;
1547 		return RX_QUEUED;
1548 	}
1549 
1550 	rx->skb = __skb_dequeue(&entry->skb_list);
1551 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1552 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1553 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1554 					      GFP_ATOMIC))) {
1555 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1556 			__skb_queue_purge(&entry->skb_list);
1557 			return RX_DROP_UNUSABLE;
1558 		}
1559 	}
1560 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1561 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1562 		dev_kfree_skb(skb);
1563 	}
1564 
1565 	/* Complete frame has been reassembled - process it now */
1566 	status = IEEE80211_SKB_RXCB(rx->skb);
1567 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1568 
1569  out:
1570 	if (rx->sta)
1571 		rx->sta->rx_packets++;
1572 	if (is_multicast_ether_addr(hdr->addr1))
1573 		rx->local->dot11MulticastReceivedFrameCount++;
1574 	else
1575 		ieee80211_led_rx(rx->local);
1576 	return RX_CONTINUE;
1577 }
1578 
1579 static int
1580 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1581 {
1582 	if (unlikely(!rx->sta ||
1583 	    !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1584 		return -EACCES;
1585 
1586 	return 0;
1587 }
1588 
1589 static int
1590 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1591 {
1592 	struct sk_buff *skb = rx->skb;
1593 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1594 
1595 	/*
1596 	 * Pass through unencrypted frames if the hardware has
1597 	 * decrypted them already.
1598 	 */
1599 	if (status->flag & RX_FLAG_DECRYPTED)
1600 		return 0;
1601 
1602 	/* Drop unencrypted frames if key is set. */
1603 	if (unlikely(!ieee80211_has_protected(fc) &&
1604 		     !ieee80211_is_nullfunc(fc) &&
1605 		     ieee80211_is_data(fc) &&
1606 		     (rx->key || rx->sdata->drop_unencrypted)))
1607 		return -EACCES;
1608 
1609 	return 0;
1610 }
1611 
1612 static int
1613 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1614 {
1615 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1616 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1617 	__le16 fc = hdr->frame_control;
1618 
1619 	/*
1620 	 * Pass through unencrypted frames if the hardware has
1621 	 * decrypted them already.
1622 	 */
1623 	if (status->flag & RX_FLAG_DECRYPTED)
1624 		return 0;
1625 
1626 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1627 		if (unlikely(!ieee80211_has_protected(fc) &&
1628 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1629 			     rx->key)) {
1630 			if (ieee80211_is_deauth(fc))
1631 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1632 							    rx->skb->data,
1633 							    rx->skb->len);
1634 			else if (ieee80211_is_disassoc(fc))
1635 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1636 							      rx->skb->data,
1637 							      rx->skb->len);
1638 			return -EACCES;
1639 		}
1640 		/* BIP does not use Protected field, so need to check MMIE */
1641 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1642 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1643 			if (ieee80211_is_deauth(fc))
1644 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1645 							    rx->skb->data,
1646 							    rx->skb->len);
1647 			else if (ieee80211_is_disassoc(fc))
1648 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1649 							      rx->skb->data,
1650 							      rx->skb->len);
1651 			return -EACCES;
1652 		}
1653 		/*
1654 		 * When using MFP, Action frames are not allowed prior to
1655 		 * having configured keys.
1656 		 */
1657 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1658 			     ieee80211_is_robust_mgmt_frame(
1659 				     (struct ieee80211_hdr *) rx->skb->data)))
1660 			return -EACCES;
1661 	}
1662 
1663 	return 0;
1664 }
1665 
1666 static int
1667 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1668 {
1669 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1670 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1671 	bool check_port_control = false;
1672 	struct ethhdr *ehdr;
1673 	int ret;
1674 
1675 	*port_control = false;
1676 	if (ieee80211_has_a4(hdr->frame_control) &&
1677 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1678 		return -1;
1679 
1680 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1681 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1682 
1683 		if (!sdata->u.mgd.use_4addr)
1684 			return -1;
1685 		else
1686 			check_port_control = true;
1687 	}
1688 
1689 	if (is_multicast_ether_addr(hdr->addr1) &&
1690 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1691 		return -1;
1692 
1693 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1694 	if (ret < 0)
1695 		return ret;
1696 
1697 	ehdr = (struct ethhdr *) rx->skb->data;
1698 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1699 		*port_control = true;
1700 	else if (check_port_control)
1701 		return -1;
1702 
1703 	return 0;
1704 }
1705 
1706 /*
1707  * requires that rx->skb is a frame with ethernet header
1708  */
1709 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1710 {
1711 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1712 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1713 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1714 
1715 	/*
1716 	 * Allow EAPOL frames to us/the PAE group address regardless
1717 	 * of whether the frame was encrypted or not.
1718 	 */
1719 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1720 	    (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1721 	     compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1722 		return true;
1723 
1724 	if (ieee80211_802_1x_port_control(rx) ||
1725 	    ieee80211_drop_unencrypted(rx, fc))
1726 		return false;
1727 
1728 	return true;
1729 }
1730 
1731 /*
1732  * requires that rx->skb is a frame with ethernet header
1733  */
1734 static void
1735 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1736 {
1737 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1738 	struct net_device *dev = sdata->dev;
1739 	struct sk_buff *skb, *xmit_skb;
1740 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1741 	struct sta_info *dsta;
1742 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1743 
1744 	skb = rx->skb;
1745 	xmit_skb = NULL;
1746 
1747 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1748 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1749 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1750 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1751 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1752 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1753 			/*
1754 			 * send multicast frames both to higher layers in
1755 			 * local net stack and back to the wireless medium
1756 			 */
1757 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1758 			if (!xmit_skb && net_ratelimit())
1759 				printk(KERN_DEBUG "%s: failed to clone "
1760 				       "multicast frame\n", dev->name);
1761 		} else {
1762 			dsta = sta_info_get(sdata, skb->data);
1763 			if (dsta) {
1764 				/*
1765 				 * The destination station is associated to
1766 				 * this AP (in this VLAN), so send the frame
1767 				 * directly to it and do not pass it to local
1768 				 * net stack.
1769 				 */
1770 				xmit_skb = skb;
1771 				skb = NULL;
1772 			}
1773 		}
1774 	}
1775 
1776 	if (skb) {
1777 		int align __maybe_unused;
1778 
1779 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1780 		/*
1781 		 * 'align' will only take the values 0 or 2 here
1782 		 * since all frames are required to be aligned
1783 		 * to 2-byte boundaries when being passed to
1784 		 * mac80211. That also explains the __skb_push()
1785 		 * below.
1786 		 */
1787 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1788 		if (align) {
1789 			if (WARN_ON(skb_headroom(skb) < 3)) {
1790 				dev_kfree_skb(skb);
1791 				skb = NULL;
1792 			} else {
1793 				u8 *data = skb->data;
1794 				size_t len = skb_headlen(skb);
1795 				skb->data -= align;
1796 				memmove(skb->data, data, len);
1797 				skb_set_tail_pointer(skb, len);
1798 			}
1799 		}
1800 #endif
1801 
1802 		if (skb) {
1803 			/* deliver to local stack */
1804 			skb->protocol = eth_type_trans(skb, dev);
1805 			memset(skb->cb, 0, sizeof(skb->cb));
1806 			netif_receive_skb(skb);
1807 		}
1808 	}
1809 
1810 	if (xmit_skb) {
1811 		/*
1812 		 * Send to wireless media and increase priority by 256 to
1813 		 * keep the received priority instead of reclassifying
1814 		 * the frame (see cfg80211_classify8021d).
1815 		 */
1816 		xmit_skb->priority += 256;
1817 		xmit_skb->protocol = htons(ETH_P_802_3);
1818 		skb_reset_network_header(xmit_skb);
1819 		skb_reset_mac_header(xmit_skb);
1820 		dev_queue_xmit(xmit_skb);
1821 	}
1822 }
1823 
1824 static ieee80211_rx_result debug_noinline
1825 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1826 {
1827 	struct net_device *dev = rx->sdata->dev;
1828 	struct sk_buff *skb = rx->skb;
1829 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1830 	__le16 fc = hdr->frame_control;
1831 	struct sk_buff_head frame_list;
1832 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1833 
1834 	if (unlikely(!ieee80211_is_data(fc)))
1835 		return RX_CONTINUE;
1836 
1837 	if (unlikely(!ieee80211_is_data_present(fc)))
1838 		return RX_DROP_MONITOR;
1839 
1840 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1841 		return RX_CONTINUE;
1842 
1843 	if (ieee80211_has_a4(hdr->frame_control) &&
1844 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1845 	    !rx->sdata->u.vlan.sta)
1846 		return RX_DROP_UNUSABLE;
1847 
1848 	if (is_multicast_ether_addr(hdr->addr1) &&
1849 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1850 	      rx->sdata->u.vlan.sta) ||
1851 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1852 	      rx->sdata->u.mgd.use_4addr)))
1853 		return RX_DROP_UNUSABLE;
1854 
1855 	skb->dev = dev;
1856 	__skb_queue_head_init(&frame_list);
1857 
1858 	if (skb_linearize(skb))
1859 		return RX_DROP_UNUSABLE;
1860 
1861 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1862 				 rx->sdata->vif.type,
1863 				 rx->local->hw.extra_tx_headroom, true);
1864 
1865 	while (!skb_queue_empty(&frame_list)) {
1866 		rx->skb = __skb_dequeue(&frame_list);
1867 
1868 		if (!ieee80211_frame_allowed(rx, fc)) {
1869 			dev_kfree_skb(rx->skb);
1870 			continue;
1871 		}
1872 		dev->stats.rx_packets++;
1873 		dev->stats.rx_bytes += rx->skb->len;
1874 
1875 		ieee80211_deliver_skb(rx);
1876 	}
1877 
1878 	return RX_QUEUED;
1879 }
1880 
1881 #ifdef CONFIG_MAC80211_MESH
1882 static ieee80211_rx_result
1883 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1884 {
1885 	struct ieee80211_hdr *fwd_hdr, *hdr;
1886 	struct ieee80211_tx_info *info;
1887 	struct ieee80211s_hdr *mesh_hdr;
1888 	struct sk_buff *skb = rx->skb, *fwd_skb;
1889 	struct ieee80211_local *local = rx->local;
1890 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1891 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1892 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1893 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1894 	u16 q, hdrlen;
1895 
1896 	hdr = (struct ieee80211_hdr *) skb->data;
1897 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1898 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1899 
1900 	/* frame is in RMC, don't forward */
1901 	if (ieee80211_is_data(hdr->frame_control) &&
1902 	    is_multicast_ether_addr(hdr->addr1) &&
1903 	    mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1904 		return RX_DROP_MONITOR;
1905 
1906 	if (!ieee80211_is_data(hdr->frame_control))
1907 		return RX_CONTINUE;
1908 
1909 	if (!mesh_hdr->ttl)
1910 		return RX_DROP_MONITOR;
1911 
1912 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
1913 		struct mesh_path *mppath;
1914 		char *proxied_addr;
1915 		char *mpp_addr;
1916 
1917 		if (is_multicast_ether_addr(hdr->addr1)) {
1918 			mpp_addr = hdr->addr3;
1919 			proxied_addr = mesh_hdr->eaddr1;
1920 		} else {
1921 			mpp_addr = hdr->addr4;
1922 			proxied_addr = mesh_hdr->eaddr2;
1923 		}
1924 
1925 		rcu_read_lock();
1926 		mppath = mpp_path_lookup(proxied_addr, sdata);
1927 		if (!mppath) {
1928 			mpp_path_add(proxied_addr, mpp_addr, sdata);
1929 		} else {
1930 			spin_lock_bh(&mppath->state_lock);
1931 			if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1932 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1933 			spin_unlock_bh(&mppath->state_lock);
1934 		}
1935 		rcu_read_unlock();
1936 	}
1937 
1938 	/* Frame has reached destination.  Don't forward */
1939 	if (!is_multicast_ether_addr(hdr->addr1) &&
1940 	    compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1941 		return RX_CONTINUE;
1942 
1943 	q = ieee80211_select_queue_80211(local, skb, hdr);
1944 	if (ieee80211_queue_stopped(&local->hw, q)) {
1945 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1946 		return RX_DROP_MONITOR;
1947 	}
1948 	skb_set_queue_mapping(skb, q);
1949 
1950 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1951 		goto out;
1952 
1953 	if (!--mesh_hdr->ttl) {
1954 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1955 		return RX_DROP_MONITOR;
1956 	}
1957 
1958 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
1959 	if (!fwd_skb) {
1960 		if (net_ratelimit())
1961 			printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1962 					sdata->name);
1963 		goto out;
1964 	}
1965 
1966 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1967 	info = IEEE80211_SKB_CB(fwd_skb);
1968 	memset(info, 0, sizeof(*info));
1969 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1970 	info->control.vif = &rx->sdata->vif;
1971 	info->control.jiffies = jiffies;
1972 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1973 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1974 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1975 	} else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1976 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1977 	} else {
1978 		/* unable to resolve next hop */
1979 		mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
1980 				    0, reason, fwd_hdr->addr2, sdata);
1981 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
1982 		kfree_skb(fwd_skb);
1983 		return RX_DROP_MONITOR;
1984 	}
1985 
1986 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
1987 	ieee80211_add_pending_skb(local, fwd_skb);
1988  out:
1989 	if (is_multicast_ether_addr(hdr->addr1) ||
1990 	    sdata->dev->flags & IFF_PROMISC)
1991 		return RX_CONTINUE;
1992 	else
1993 		return RX_DROP_MONITOR;
1994 }
1995 #endif
1996 
1997 static ieee80211_rx_result debug_noinline
1998 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1999 {
2000 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2001 	struct ieee80211_local *local = rx->local;
2002 	struct net_device *dev = sdata->dev;
2003 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2004 	__le16 fc = hdr->frame_control;
2005 	bool port_control;
2006 	int err;
2007 
2008 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2009 		return RX_CONTINUE;
2010 
2011 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2012 		return RX_DROP_MONITOR;
2013 
2014 	/*
2015 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2016 	 * also drop the frame to cooked monitor interfaces.
2017 	 */
2018 	if (ieee80211_has_a4(hdr->frame_control) &&
2019 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2020 		if (rx->sta &&
2021 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2022 			cfg80211_rx_unexpected_4addr_frame(
2023 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2024 		return RX_DROP_MONITOR;
2025 	}
2026 
2027 	err = __ieee80211_data_to_8023(rx, &port_control);
2028 	if (unlikely(err))
2029 		return RX_DROP_UNUSABLE;
2030 
2031 	if (!ieee80211_frame_allowed(rx, fc))
2032 		return RX_DROP_MONITOR;
2033 
2034 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2035 	    unlikely(port_control) && sdata->bss) {
2036 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2037 				     u.ap);
2038 		dev = sdata->dev;
2039 		rx->sdata = sdata;
2040 	}
2041 
2042 	rx->skb->dev = dev;
2043 
2044 	dev->stats.rx_packets++;
2045 	dev->stats.rx_bytes += rx->skb->len;
2046 
2047 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2048 	    !is_multicast_ether_addr(
2049 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2050 	    (!local->scanning &&
2051 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2052 			mod_timer(&local->dynamic_ps_timer, jiffies +
2053 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2054 	}
2055 
2056 	ieee80211_deliver_skb(rx);
2057 
2058 	return RX_QUEUED;
2059 }
2060 
2061 static ieee80211_rx_result debug_noinline
2062 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2063 {
2064 	struct ieee80211_local *local = rx->local;
2065 	struct ieee80211_hw *hw = &local->hw;
2066 	struct sk_buff *skb = rx->skb;
2067 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2068 	struct tid_ampdu_rx *tid_agg_rx;
2069 	u16 start_seq_num;
2070 	u16 tid;
2071 
2072 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2073 		return RX_CONTINUE;
2074 
2075 	if (ieee80211_is_back_req(bar->frame_control)) {
2076 		struct {
2077 			__le16 control, start_seq_num;
2078 		} __packed bar_data;
2079 
2080 		if (!rx->sta)
2081 			return RX_DROP_MONITOR;
2082 
2083 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2084 				  &bar_data, sizeof(bar_data)))
2085 			return RX_DROP_MONITOR;
2086 
2087 		tid = le16_to_cpu(bar_data.control) >> 12;
2088 
2089 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2090 		if (!tid_agg_rx)
2091 			return RX_DROP_MONITOR;
2092 
2093 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2094 
2095 		/* reset session timer */
2096 		if (tid_agg_rx->timeout)
2097 			mod_timer(&tid_agg_rx->session_timer,
2098 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2099 
2100 		spin_lock(&tid_agg_rx->reorder_lock);
2101 		/* release stored frames up to start of BAR */
2102 		ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
2103 		spin_unlock(&tid_agg_rx->reorder_lock);
2104 
2105 		kfree_skb(skb);
2106 		return RX_QUEUED;
2107 	}
2108 
2109 	/*
2110 	 * After this point, we only want management frames,
2111 	 * so we can drop all remaining control frames to
2112 	 * cooked monitor interfaces.
2113 	 */
2114 	return RX_DROP_MONITOR;
2115 }
2116 
2117 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2118 					   struct ieee80211_mgmt *mgmt,
2119 					   size_t len)
2120 {
2121 	struct ieee80211_local *local = sdata->local;
2122 	struct sk_buff *skb;
2123 	struct ieee80211_mgmt *resp;
2124 
2125 	if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
2126 		/* Not to own unicast address */
2127 		return;
2128 	}
2129 
2130 	if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
2131 	    compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
2132 		/* Not from the current AP or not associated yet. */
2133 		return;
2134 	}
2135 
2136 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2137 		/* Too short SA Query request frame */
2138 		return;
2139 	}
2140 
2141 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2142 	if (skb == NULL)
2143 		return;
2144 
2145 	skb_reserve(skb, local->hw.extra_tx_headroom);
2146 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2147 	memset(resp, 0, 24);
2148 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2149 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2150 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2151 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2152 					  IEEE80211_STYPE_ACTION);
2153 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2154 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2155 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2156 	memcpy(resp->u.action.u.sa_query.trans_id,
2157 	       mgmt->u.action.u.sa_query.trans_id,
2158 	       WLAN_SA_QUERY_TR_ID_LEN);
2159 
2160 	ieee80211_tx_skb(sdata, skb);
2161 }
2162 
2163 static ieee80211_rx_result debug_noinline
2164 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2165 {
2166 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2167 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2168 
2169 	/*
2170 	 * From here on, look only at management frames.
2171 	 * Data and control frames are already handled,
2172 	 * and unknown (reserved) frames are useless.
2173 	 */
2174 	if (rx->skb->len < 24)
2175 		return RX_DROP_MONITOR;
2176 
2177 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2178 		return RX_DROP_MONITOR;
2179 
2180 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2181 	    ieee80211_is_beacon(mgmt->frame_control) &&
2182 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2183 		struct ieee80211_rx_status *status;
2184 
2185 		status = IEEE80211_SKB_RXCB(rx->skb);
2186 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2187 					    rx->skb->data, rx->skb->len,
2188 					    status->freq, GFP_ATOMIC);
2189 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2190 	}
2191 
2192 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2193 		return RX_DROP_MONITOR;
2194 
2195 	if (ieee80211_drop_unencrypted_mgmt(rx))
2196 		return RX_DROP_UNUSABLE;
2197 
2198 	return RX_CONTINUE;
2199 }
2200 
2201 static ieee80211_rx_result debug_noinline
2202 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2203 {
2204 	struct ieee80211_local *local = rx->local;
2205 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2206 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2207 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2208 	int len = rx->skb->len;
2209 
2210 	if (!ieee80211_is_action(mgmt->frame_control))
2211 		return RX_CONTINUE;
2212 
2213 	/* drop too small frames */
2214 	if (len < IEEE80211_MIN_ACTION_SIZE)
2215 		return RX_DROP_UNUSABLE;
2216 
2217 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2218 		return RX_DROP_UNUSABLE;
2219 
2220 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2221 		return RX_DROP_UNUSABLE;
2222 
2223 	switch (mgmt->u.action.category) {
2224 	case WLAN_CATEGORY_HT:
2225 		/* reject HT action frames from stations not supporting HT */
2226 		if (!rx->sta->sta.ht_cap.ht_supported)
2227 			goto invalid;
2228 
2229 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2230 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2231 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2232 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2233 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2234 			break;
2235 
2236 		/* verify action & smps_control are present */
2237 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2238 			goto invalid;
2239 
2240 		switch (mgmt->u.action.u.ht_smps.action) {
2241 		case WLAN_HT_ACTION_SMPS: {
2242 			struct ieee80211_supported_band *sband;
2243 			u8 smps;
2244 
2245 			/* convert to HT capability */
2246 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2247 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2248 				smps = WLAN_HT_CAP_SM_PS_DISABLED;
2249 				break;
2250 			case WLAN_HT_SMPS_CONTROL_STATIC:
2251 				smps = WLAN_HT_CAP_SM_PS_STATIC;
2252 				break;
2253 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2254 				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2255 				break;
2256 			default:
2257 				goto invalid;
2258 			}
2259 			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2260 
2261 			/* if no change do nothing */
2262 			if ((rx->sta->sta.ht_cap.cap &
2263 					IEEE80211_HT_CAP_SM_PS) == smps)
2264 				goto handled;
2265 
2266 			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2267 			rx->sta->sta.ht_cap.cap |= smps;
2268 
2269 			sband = rx->local->hw.wiphy->bands[status->band];
2270 
2271 			rate_control_rate_update(local, sband, rx->sta,
2272 						 IEEE80211_RC_SMPS_CHANGED,
2273 						 local->_oper_channel_type);
2274 			goto handled;
2275 		}
2276 		default:
2277 			goto invalid;
2278 		}
2279 
2280 		break;
2281 	case WLAN_CATEGORY_BACK:
2282 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2283 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2284 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2285 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2286 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2287 			break;
2288 
2289 		/* verify action_code is present */
2290 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2291 			break;
2292 
2293 		switch (mgmt->u.action.u.addba_req.action_code) {
2294 		case WLAN_ACTION_ADDBA_REQ:
2295 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2296 				   sizeof(mgmt->u.action.u.addba_req)))
2297 				goto invalid;
2298 			break;
2299 		case WLAN_ACTION_ADDBA_RESP:
2300 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2301 				   sizeof(mgmt->u.action.u.addba_resp)))
2302 				goto invalid;
2303 			break;
2304 		case WLAN_ACTION_DELBA:
2305 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2306 				   sizeof(mgmt->u.action.u.delba)))
2307 				goto invalid;
2308 			break;
2309 		default:
2310 			goto invalid;
2311 		}
2312 
2313 		goto queue;
2314 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2315 		if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2316 			break;
2317 
2318 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2319 			break;
2320 
2321 		/* verify action_code is present */
2322 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2323 			break;
2324 
2325 		switch (mgmt->u.action.u.measurement.action_code) {
2326 		case WLAN_ACTION_SPCT_MSR_REQ:
2327 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2328 				   sizeof(mgmt->u.action.u.measurement)))
2329 				break;
2330 			ieee80211_process_measurement_req(sdata, mgmt, len);
2331 			goto handled;
2332 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2333 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2334 				   sizeof(mgmt->u.action.u.chan_switch)))
2335 				break;
2336 
2337 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2338 				break;
2339 
2340 			if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2341 				break;
2342 
2343 			goto queue;
2344 		}
2345 		break;
2346 	case WLAN_CATEGORY_SA_QUERY:
2347 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2348 			   sizeof(mgmt->u.action.u.sa_query)))
2349 			break;
2350 
2351 		switch (mgmt->u.action.u.sa_query.action) {
2352 		case WLAN_ACTION_SA_QUERY_REQUEST:
2353 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2354 				break;
2355 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2356 			goto handled;
2357 		}
2358 		break;
2359 	case WLAN_CATEGORY_SELF_PROTECTED:
2360 		switch (mgmt->u.action.u.self_prot.action_code) {
2361 		case WLAN_SP_MESH_PEERING_OPEN:
2362 		case WLAN_SP_MESH_PEERING_CLOSE:
2363 		case WLAN_SP_MESH_PEERING_CONFIRM:
2364 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2365 				goto invalid;
2366 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2367 				/* userspace handles this frame */
2368 				break;
2369 			goto queue;
2370 		case WLAN_SP_MGK_INFORM:
2371 		case WLAN_SP_MGK_ACK:
2372 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2373 				goto invalid;
2374 			break;
2375 		}
2376 		break;
2377 	case WLAN_CATEGORY_MESH_ACTION:
2378 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2379 			break;
2380 		if (mesh_action_is_path_sel(mgmt) &&
2381 		  (!mesh_path_sel_is_hwmp(sdata)))
2382 			break;
2383 		goto queue;
2384 	}
2385 
2386 	return RX_CONTINUE;
2387 
2388  invalid:
2389 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2390 	/* will return in the next handlers */
2391 	return RX_CONTINUE;
2392 
2393  handled:
2394 	if (rx->sta)
2395 		rx->sta->rx_packets++;
2396 	dev_kfree_skb(rx->skb);
2397 	return RX_QUEUED;
2398 
2399  queue:
2400 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2401 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2402 	ieee80211_queue_work(&local->hw, &sdata->work);
2403 	if (rx->sta)
2404 		rx->sta->rx_packets++;
2405 	return RX_QUEUED;
2406 }
2407 
2408 static ieee80211_rx_result debug_noinline
2409 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2410 {
2411 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2412 
2413 	/* skip known-bad action frames and return them in the next handler */
2414 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2415 		return RX_CONTINUE;
2416 
2417 	/*
2418 	 * Getting here means the kernel doesn't know how to handle
2419 	 * it, but maybe userspace does ... include returned frames
2420 	 * so userspace can register for those to know whether ones
2421 	 * it transmitted were processed or returned.
2422 	 */
2423 
2424 	if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2425 			     rx->skb->data, rx->skb->len,
2426 			     GFP_ATOMIC)) {
2427 		if (rx->sta)
2428 			rx->sta->rx_packets++;
2429 		dev_kfree_skb(rx->skb);
2430 		return RX_QUEUED;
2431 	}
2432 
2433 
2434 	return RX_CONTINUE;
2435 }
2436 
2437 static ieee80211_rx_result debug_noinline
2438 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2439 {
2440 	struct ieee80211_local *local = rx->local;
2441 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2442 	struct sk_buff *nskb;
2443 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2444 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2445 
2446 	if (!ieee80211_is_action(mgmt->frame_control))
2447 		return RX_CONTINUE;
2448 
2449 	/*
2450 	 * For AP mode, hostapd is responsible for handling any action
2451 	 * frames that we didn't handle, including returning unknown
2452 	 * ones. For all other modes we will return them to the sender,
2453 	 * setting the 0x80 bit in the action category, as required by
2454 	 * 802.11-2007 7.3.1.11.
2455 	 * Newer versions of hostapd shall also use the management frame
2456 	 * registration mechanisms, but older ones still use cooked
2457 	 * monitor interfaces so push all frames there.
2458 	 */
2459 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2460 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2461 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2462 		return RX_DROP_MONITOR;
2463 
2464 	/* do not return rejected action frames */
2465 	if (mgmt->u.action.category & 0x80)
2466 		return RX_DROP_UNUSABLE;
2467 
2468 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2469 			       GFP_ATOMIC);
2470 	if (nskb) {
2471 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2472 
2473 		nmgmt->u.action.category |= 0x80;
2474 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2475 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2476 
2477 		memset(nskb->cb, 0, sizeof(nskb->cb));
2478 
2479 		ieee80211_tx_skb(rx->sdata, nskb);
2480 	}
2481 	dev_kfree_skb(rx->skb);
2482 	return RX_QUEUED;
2483 }
2484 
2485 static ieee80211_rx_result debug_noinline
2486 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2487 {
2488 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2489 	ieee80211_rx_result rxs;
2490 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2491 	__le16 stype;
2492 
2493 	rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2494 	if (rxs != RX_CONTINUE)
2495 		return rxs;
2496 
2497 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2498 
2499 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2500 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2501 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2502 		return RX_DROP_MONITOR;
2503 
2504 	switch (stype) {
2505 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2506 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2507 		/* process for all: mesh, mlme, ibss */
2508 		break;
2509 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2510 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2511 		if (is_multicast_ether_addr(mgmt->da) &&
2512 		    !is_broadcast_ether_addr(mgmt->da))
2513 			return RX_DROP_MONITOR;
2514 
2515 		/* process only for station */
2516 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2517 			return RX_DROP_MONITOR;
2518 		break;
2519 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2520 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2521 		/* process only for ibss */
2522 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2523 			return RX_DROP_MONITOR;
2524 		break;
2525 	default:
2526 		return RX_DROP_MONITOR;
2527 	}
2528 
2529 	/* queue up frame and kick off work to process it */
2530 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2531 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2532 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2533 	if (rx->sta)
2534 		rx->sta->rx_packets++;
2535 
2536 	return RX_QUEUED;
2537 }
2538 
2539 /* TODO: use IEEE80211_RX_FRAGMENTED */
2540 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2541 					struct ieee80211_rate *rate)
2542 {
2543 	struct ieee80211_sub_if_data *sdata;
2544 	struct ieee80211_local *local = rx->local;
2545 	struct ieee80211_rtap_hdr {
2546 		struct ieee80211_radiotap_header hdr;
2547 		u8 flags;
2548 		u8 rate_or_pad;
2549 		__le16 chan_freq;
2550 		__le16 chan_flags;
2551 	} __packed *rthdr;
2552 	struct sk_buff *skb = rx->skb, *skb2;
2553 	struct net_device *prev_dev = NULL;
2554 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2555 
2556 	/*
2557 	 * If cooked monitor has been processed already, then
2558 	 * don't do it again. If not, set the flag.
2559 	 */
2560 	if (rx->flags & IEEE80211_RX_CMNTR)
2561 		goto out_free_skb;
2562 	rx->flags |= IEEE80211_RX_CMNTR;
2563 
2564 	/* If there are no cooked monitor interfaces, just free the SKB */
2565 	if (!local->cooked_mntrs)
2566 		goto out_free_skb;
2567 
2568 	if (skb_headroom(skb) < sizeof(*rthdr) &&
2569 	    pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2570 		goto out_free_skb;
2571 
2572 	rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2573 	memset(rthdr, 0, sizeof(*rthdr));
2574 	rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2575 	rthdr->hdr.it_present =
2576 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2577 			    (1 << IEEE80211_RADIOTAP_CHANNEL));
2578 
2579 	if (rate) {
2580 		rthdr->rate_or_pad = rate->bitrate / 5;
2581 		rthdr->hdr.it_present |=
2582 			cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2583 	}
2584 	rthdr->chan_freq = cpu_to_le16(status->freq);
2585 
2586 	if (status->band == IEEE80211_BAND_5GHZ)
2587 		rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2588 						IEEE80211_CHAN_5GHZ);
2589 	else
2590 		rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2591 						IEEE80211_CHAN_2GHZ);
2592 
2593 	skb_set_mac_header(skb, 0);
2594 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2595 	skb->pkt_type = PACKET_OTHERHOST;
2596 	skb->protocol = htons(ETH_P_802_2);
2597 
2598 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2599 		if (!ieee80211_sdata_running(sdata))
2600 			continue;
2601 
2602 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2603 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2604 			continue;
2605 
2606 		if (prev_dev) {
2607 			skb2 = skb_clone(skb, GFP_ATOMIC);
2608 			if (skb2) {
2609 				skb2->dev = prev_dev;
2610 				netif_receive_skb(skb2);
2611 			}
2612 		}
2613 
2614 		prev_dev = sdata->dev;
2615 		sdata->dev->stats.rx_packets++;
2616 		sdata->dev->stats.rx_bytes += skb->len;
2617 	}
2618 
2619 	if (prev_dev) {
2620 		skb->dev = prev_dev;
2621 		netif_receive_skb(skb);
2622 		return;
2623 	}
2624 
2625  out_free_skb:
2626 	dev_kfree_skb(skb);
2627 }
2628 
2629 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2630 					 ieee80211_rx_result res)
2631 {
2632 	switch (res) {
2633 	case RX_DROP_MONITOR:
2634 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2635 		if (rx->sta)
2636 			rx->sta->rx_dropped++;
2637 		/* fall through */
2638 	case RX_CONTINUE: {
2639 		struct ieee80211_rate *rate = NULL;
2640 		struct ieee80211_supported_band *sband;
2641 		struct ieee80211_rx_status *status;
2642 
2643 		status = IEEE80211_SKB_RXCB((rx->skb));
2644 
2645 		sband = rx->local->hw.wiphy->bands[status->band];
2646 		if (!(status->flag & RX_FLAG_HT))
2647 			rate = &sband->bitrates[status->rate_idx];
2648 
2649 		ieee80211_rx_cooked_monitor(rx, rate);
2650 		break;
2651 		}
2652 	case RX_DROP_UNUSABLE:
2653 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2654 		if (rx->sta)
2655 			rx->sta->rx_dropped++;
2656 		dev_kfree_skb(rx->skb);
2657 		break;
2658 	case RX_QUEUED:
2659 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2660 		break;
2661 	}
2662 }
2663 
2664 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2665 {
2666 	ieee80211_rx_result res = RX_DROP_MONITOR;
2667 	struct sk_buff *skb;
2668 
2669 #define CALL_RXH(rxh)			\
2670 	do {				\
2671 		res = rxh(rx);		\
2672 		if (res != RX_CONTINUE)	\
2673 			goto rxh_next;  \
2674 	} while (0);
2675 
2676 	spin_lock(&rx->local->rx_skb_queue.lock);
2677 	if (rx->local->running_rx_handler)
2678 		goto unlock;
2679 
2680 	rx->local->running_rx_handler = true;
2681 
2682 	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2683 		spin_unlock(&rx->local->rx_skb_queue.lock);
2684 
2685 		/*
2686 		 * all the other fields are valid across frames
2687 		 * that belong to an aMPDU since they are on the
2688 		 * same TID from the same station
2689 		 */
2690 		rx->skb = skb;
2691 
2692 		CALL_RXH(ieee80211_rx_h_decrypt)
2693 		CALL_RXH(ieee80211_rx_h_check_more_data)
2694 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2695 		CALL_RXH(ieee80211_rx_h_sta_process)
2696 		CALL_RXH(ieee80211_rx_h_defragment)
2697 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2698 		/* must be after MMIC verify so header is counted in MPDU mic */
2699 #ifdef CONFIG_MAC80211_MESH
2700 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2701 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2702 #endif
2703 		CALL_RXH(ieee80211_rx_h_amsdu)
2704 		CALL_RXH(ieee80211_rx_h_data)
2705 		CALL_RXH(ieee80211_rx_h_ctrl);
2706 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2707 		CALL_RXH(ieee80211_rx_h_action)
2708 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2709 		CALL_RXH(ieee80211_rx_h_action_return)
2710 		CALL_RXH(ieee80211_rx_h_mgmt)
2711 
2712  rxh_next:
2713 		ieee80211_rx_handlers_result(rx, res);
2714 		spin_lock(&rx->local->rx_skb_queue.lock);
2715 #undef CALL_RXH
2716 	}
2717 
2718 	rx->local->running_rx_handler = false;
2719 
2720  unlock:
2721 	spin_unlock(&rx->local->rx_skb_queue.lock);
2722 }
2723 
2724 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2725 {
2726 	ieee80211_rx_result res = RX_DROP_MONITOR;
2727 
2728 #define CALL_RXH(rxh)			\
2729 	do {				\
2730 		res = rxh(rx);		\
2731 		if (res != RX_CONTINUE)	\
2732 			goto rxh_next;  \
2733 	} while (0);
2734 
2735 	CALL_RXH(ieee80211_rx_h_passive_scan)
2736 	CALL_RXH(ieee80211_rx_h_check)
2737 
2738 	ieee80211_rx_reorder_ampdu(rx);
2739 
2740 	ieee80211_rx_handlers(rx);
2741 	return;
2742 
2743  rxh_next:
2744 	ieee80211_rx_handlers_result(rx, res);
2745 
2746 #undef CALL_RXH
2747 }
2748 
2749 /*
2750  * This function makes calls into the RX path, therefore
2751  * it has to be invoked under RCU read lock.
2752  */
2753 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2754 {
2755 	struct ieee80211_rx_data rx = {
2756 		.sta = sta,
2757 		.sdata = sta->sdata,
2758 		.local = sta->local,
2759 		/* This is OK -- must be QoS data frame */
2760 		.security_idx = tid,
2761 		.seqno_idx = tid,
2762 		.flags = 0,
2763 	};
2764 	struct tid_ampdu_rx *tid_agg_rx;
2765 
2766 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2767 	if (!tid_agg_rx)
2768 		return;
2769 
2770 	spin_lock(&tid_agg_rx->reorder_lock);
2771 	ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
2772 	spin_unlock(&tid_agg_rx->reorder_lock);
2773 
2774 	ieee80211_rx_handlers(&rx);
2775 }
2776 
2777 /* main receive path */
2778 
2779 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2780 				struct ieee80211_hdr *hdr)
2781 {
2782 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2783 	struct sk_buff *skb = rx->skb;
2784 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2785 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2786 	int multicast = is_multicast_ether_addr(hdr->addr1);
2787 
2788 	switch (sdata->vif.type) {
2789 	case NL80211_IFTYPE_STATION:
2790 		if (!bssid && !sdata->u.mgd.use_4addr)
2791 			return 0;
2792 		if (!multicast &&
2793 		    compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2794 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2795 			    sdata->u.mgd.use_4addr)
2796 				return 0;
2797 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2798 		}
2799 		break;
2800 	case NL80211_IFTYPE_ADHOC:
2801 		if (!bssid)
2802 			return 0;
2803 		if (ieee80211_is_beacon(hdr->frame_control)) {
2804 			return 1;
2805 		}
2806 		else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2807 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2808 				return 0;
2809 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2810 		} else if (!multicast &&
2811 			   compare_ether_addr(sdata->vif.addr,
2812 					      hdr->addr1) != 0) {
2813 			if (!(sdata->dev->flags & IFF_PROMISC))
2814 				return 0;
2815 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2816 		} else if (!rx->sta) {
2817 			int rate_idx;
2818 			if (status->flag & RX_FLAG_HT)
2819 				rate_idx = 0; /* TODO: HT rates */
2820 			else
2821 				rate_idx = status->rate_idx;
2822 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2823 						 BIT(rate_idx));
2824 		}
2825 		break;
2826 	case NL80211_IFTYPE_MESH_POINT:
2827 		if (!multicast &&
2828 		    compare_ether_addr(sdata->vif.addr,
2829 				       hdr->addr1) != 0) {
2830 			if (!(sdata->dev->flags & IFF_PROMISC))
2831 				return 0;
2832 
2833 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2834 		}
2835 		break;
2836 	case NL80211_IFTYPE_AP_VLAN:
2837 	case NL80211_IFTYPE_AP:
2838 		if (!bssid) {
2839 			if (compare_ether_addr(sdata->vif.addr,
2840 					       hdr->addr1))
2841 				return 0;
2842 		} else if (!ieee80211_bssid_match(bssid,
2843 					sdata->vif.addr)) {
2844 			/*
2845 			 * Accept public action frames even when the
2846 			 * BSSID doesn't match, this is used for P2P
2847 			 * and location updates. Note that mac80211
2848 			 * itself never looks at these frames.
2849 			 */
2850 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2851 			    ieee80211_is_public_action(hdr, skb->len))
2852 				return 1;
2853 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2854 			    !ieee80211_is_beacon(hdr->frame_control))
2855 				return 0;
2856 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2857 		}
2858 		break;
2859 	case NL80211_IFTYPE_WDS:
2860 		if (bssid || !ieee80211_is_data(hdr->frame_control))
2861 			return 0;
2862 		if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2863 			return 0;
2864 		break;
2865 	default:
2866 		/* should never get here */
2867 		WARN_ON(1);
2868 		break;
2869 	}
2870 
2871 	return 1;
2872 }
2873 
2874 /*
2875  * This function returns whether or not the SKB
2876  * was destined for RX processing or not, which,
2877  * if consume is true, is equivalent to whether
2878  * or not the skb was consumed.
2879  */
2880 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2881 					    struct sk_buff *skb, bool consume)
2882 {
2883 	struct ieee80211_local *local = rx->local;
2884 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2885 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2886 	struct ieee80211_hdr *hdr = (void *)skb->data;
2887 	int prepares;
2888 
2889 	rx->skb = skb;
2890 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
2891 	prepares = prepare_for_handlers(rx, hdr);
2892 
2893 	if (!prepares)
2894 		return false;
2895 
2896 	if (!consume) {
2897 		skb = skb_copy(skb, GFP_ATOMIC);
2898 		if (!skb) {
2899 			if (net_ratelimit())
2900 				wiphy_debug(local->hw.wiphy,
2901 					"failed to copy skb for %s\n",
2902 					sdata->name);
2903 			return true;
2904 		}
2905 
2906 		rx->skb = skb;
2907 	}
2908 
2909 	ieee80211_invoke_rx_handlers(rx);
2910 	return true;
2911 }
2912 
2913 /*
2914  * This is the actual Rx frames handler. as it blongs to Rx path it must
2915  * be called with rcu_read_lock protection.
2916  */
2917 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2918 					 struct sk_buff *skb)
2919 {
2920 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2921 	struct ieee80211_local *local = hw_to_local(hw);
2922 	struct ieee80211_sub_if_data *sdata;
2923 	struct ieee80211_hdr *hdr;
2924 	__le16 fc;
2925 	struct ieee80211_rx_data rx;
2926 	struct ieee80211_sub_if_data *prev;
2927 	struct sta_info *sta, *tmp, *prev_sta;
2928 	int err = 0;
2929 
2930 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2931 	memset(&rx, 0, sizeof(rx));
2932 	rx.skb = skb;
2933 	rx.local = local;
2934 
2935 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2936 		local->dot11ReceivedFragmentCount++;
2937 
2938 	if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2939 		     test_bit(SCAN_SW_SCANNING, &local->scanning)))
2940 		status->rx_flags |= IEEE80211_RX_IN_SCAN;
2941 
2942 	if (ieee80211_is_mgmt(fc))
2943 		err = skb_linearize(skb);
2944 	else
2945 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2946 
2947 	if (err) {
2948 		dev_kfree_skb(skb);
2949 		return;
2950 	}
2951 
2952 	hdr = (struct ieee80211_hdr *)skb->data;
2953 	ieee80211_parse_qos(&rx);
2954 	ieee80211_verify_alignment(&rx);
2955 
2956 	if (ieee80211_is_data(fc)) {
2957 		prev_sta = NULL;
2958 
2959 		for_each_sta_info_rx(local, hdr->addr2, sta, tmp) {
2960 			if (!prev_sta) {
2961 				prev_sta = sta;
2962 				continue;
2963 			}
2964 
2965 			rx.sta = prev_sta;
2966 			rx.sdata = prev_sta->sdata;
2967 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
2968 
2969 			prev_sta = sta;
2970 		}
2971 
2972 		if (prev_sta) {
2973 			rx.sta = prev_sta;
2974 			rx.sdata = prev_sta->sdata;
2975 
2976 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2977 				return;
2978 			goto out;
2979 		}
2980 	}
2981 
2982 	prev = NULL;
2983 
2984 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2985 		if (!ieee80211_sdata_running(sdata))
2986 			continue;
2987 
2988 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2989 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2990 			continue;
2991 
2992 		/*
2993 		 * frame is destined for this interface, but if it's
2994 		 * not also for the previous one we handle that after
2995 		 * the loop to avoid copying the SKB once too much
2996 		 */
2997 
2998 		if (!prev) {
2999 			prev = sdata;
3000 			continue;
3001 		}
3002 
3003 		rx.sta = sta_info_get_bss_rx(prev, hdr->addr2);
3004 		rx.sdata = prev;
3005 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
3006 
3007 		prev = sdata;
3008 	}
3009 
3010 	if (prev) {
3011 		rx.sta = sta_info_get_bss_rx(prev, hdr->addr2);
3012 		rx.sdata = prev;
3013 
3014 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3015 			return;
3016 	}
3017 
3018  out:
3019 	dev_kfree_skb(skb);
3020 }
3021 
3022 /*
3023  * This is the receive path handler. It is called by a low level driver when an
3024  * 802.11 MPDU is received from the hardware.
3025  */
3026 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3027 {
3028 	struct ieee80211_local *local = hw_to_local(hw);
3029 	struct ieee80211_rate *rate = NULL;
3030 	struct ieee80211_supported_band *sband;
3031 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3032 
3033 	WARN_ON_ONCE(softirq_count() == 0);
3034 
3035 	if (WARN_ON(status->band < 0 ||
3036 		    status->band >= IEEE80211_NUM_BANDS))
3037 		goto drop;
3038 
3039 	sband = local->hw.wiphy->bands[status->band];
3040 	if (WARN_ON(!sband))
3041 		goto drop;
3042 
3043 	/*
3044 	 * If we're suspending, it is possible although not too likely
3045 	 * that we'd be receiving frames after having already partially
3046 	 * quiesced the stack. We can't process such frames then since
3047 	 * that might, for example, cause stations to be added or other
3048 	 * driver callbacks be invoked.
3049 	 */
3050 	if (unlikely(local->quiescing || local->suspended))
3051 		goto drop;
3052 
3053 	/*
3054 	 * The same happens when we're not even started,
3055 	 * but that's worth a warning.
3056 	 */
3057 	if (WARN_ON(!local->started))
3058 		goto drop;
3059 
3060 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3061 		/*
3062 		 * Validate the rate, unless a PLCP error means that
3063 		 * we probably can't have a valid rate here anyway.
3064 		 */
3065 
3066 		if (status->flag & RX_FLAG_HT) {
3067 			/*
3068 			 * rate_idx is MCS index, which can be [0-76]
3069 			 * as documented on:
3070 			 *
3071 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3072 			 *
3073 			 * Anything else would be some sort of driver or
3074 			 * hardware error. The driver should catch hardware
3075 			 * errors.
3076 			 */
3077 			if (WARN((status->rate_idx < 0 ||
3078 				 status->rate_idx > 76),
3079 				 "Rate marked as an HT rate but passed "
3080 				 "status->rate_idx is not "
3081 				 "an MCS index [0-76]: %d (0x%02x)\n",
3082 				 status->rate_idx,
3083 				 status->rate_idx))
3084 				goto drop;
3085 		} else {
3086 			if (WARN_ON(status->rate_idx < 0 ||
3087 				    status->rate_idx >= sband->n_bitrates))
3088 				goto drop;
3089 			rate = &sband->bitrates[status->rate_idx];
3090 		}
3091 	}
3092 
3093 	status->rx_flags = 0;
3094 
3095 	/*
3096 	 * key references and virtual interfaces are protected using RCU
3097 	 * and this requires that we are in a read-side RCU section during
3098 	 * receive processing
3099 	 */
3100 	rcu_read_lock();
3101 
3102 	/*
3103 	 * Frames with failed FCS/PLCP checksum are not returned,
3104 	 * all other frames are returned without radiotap header
3105 	 * if it was previously present.
3106 	 * Also, frames with less than 16 bytes are dropped.
3107 	 */
3108 	skb = ieee80211_rx_monitor(local, skb, rate);
3109 	if (!skb) {
3110 		rcu_read_unlock();
3111 		return;
3112 	}
3113 
3114 	ieee80211_tpt_led_trig_rx(local,
3115 			((struct ieee80211_hdr *)skb->data)->frame_control,
3116 			skb->len);
3117 	__ieee80211_rx_handle_packet(hw, skb);
3118 
3119 	rcu_read_unlock();
3120 
3121 	return;
3122  drop:
3123 	kfree_skb(skb);
3124 }
3125 EXPORT_SYMBOL(ieee80211_rx);
3126 
3127 /* This is a version of the rx handler that can be called from hard irq
3128  * context. Post the skb on the queue and schedule the tasklet */
3129 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3130 {
3131 	struct ieee80211_local *local = hw_to_local(hw);
3132 
3133 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3134 
3135 	skb->pkt_type = IEEE80211_RX_MSG;
3136 	skb_queue_tail(&local->skb_queue, skb);
3137 	tasklet_schedule(&local->tasklet);
3138 }
3139 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3140