xref: /linux/net/mac80211/rx.c (revision ec2212088c42ff7d1362629ec26dda4f3e8bdad3)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <linux/export.h>
20 #include <net/mac80211.h>
21 #include <net/ieee80211_radiotap.h>
22 #include <asm/unaligned.h>
23 
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "led.h"
27 #include "mesh.h"
28 #include "wep.h"
29 #include "wpa.h"
30 #include "tkip.h"
31 #include "wme.h"
32 #include "rate.h"
33 
34 /*
35  * monitor mode reception
36  *
37  * This function cleans up the SKB, i.e. it removes all the stuff
38  * only useful for monitoring.
39  */
40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
41 					   struct sk_buff *skb)
42 {
43 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
44 		if (likely(skb->len > FCS_LEN))
45 			__pskb_trim(skb, skb->len - FCS_LEN);
46 		else {
47 			/* driver bug */
48 			WARN_ON(1);
49 			dev_kfree_skb(skb);
50 			skb = NULL;
51 		}
52 	}
53 
54 	return skb;
55 }
56 
57 static inline int should_drop_frame(struct sk_buff *skb,
58 				    int present_fcs_len)
59 {
60 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
61 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
62 
63 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
64 		return 1;
65 	if (unlikely(skb->len < 16 + present_fcs_len))
66 		return 1;
67 	if (ieee80211_is_ctl(hdr->frame_control) &&
68 	    !ieee80211_is_pspoll(hdr->frame_control) &&
69 	    !ieee80211_is_back_req(hdr->frame_control))
70 		return 1;
71 	return 0;
72 }
73 
74 static int
75 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
76 			  struct ieee80211_rx_status *status)
77 {
78 	int len;
79 
80 	/* always present fields */
81 	len = sizeof(struct ieee80211_radiotap_header) + 9;
82 
83 	if (status->flag & RX_FLAG_MACTIME_MPDU)
84 		len += 8;
85 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
86 		len += 1;
87 
88 	if (len & 1) /* padding for RX_FLAGS if necessary */
89 		len++;
90 
91 	if (status->flag & RX_FLAG_HT) /* HT info */
92 		len += 3;
93 
94 	return len;
95 }
96 
97 /*
98  * ieee80211_add_rx_radiotap_header - add radiotap header
99  *
100  * add a radiotap header containing all the fields which the hardware provided.
101  */
102 static void
103 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
104 				 struct sk_buff *skb,
105 				 struct ieee80211_rate *rate,
106 				 int rtap_len)
107 {
108 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
109 	struct ieee80211_radiotap_header *rthdr;
110 	unsigned char *pos;
111 	u16 rx_flags = 0;
112 
113 	rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
114 	memset(rthdr, 0, rtap_len);
115 
116 	/* radiotap header, set always present flags */
117 	rthdr->it_present =
118 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
119 			    (1 << IEEE80211_RADIOTAP_CHANNEL) |
120 			    (1 << IEEE80211_RADIOTAP_ANTENNA) |
121 			    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
122 	rthdr->it_len = cpu_to_le16(rtap_len);
123 
124 	pos = (unsigned char *)(rthdr+1);
125 
126 	/* the order of the following fields is important */
127 
128 	/* IEEE80211_RADIOTAP_TSFT */
129 	if (status->flag & RX_FLAG_MACTIME_MPDU) {
130 		put_unaligned_le64(status->mactime, pos);
131 		rthdr->it_present |=
132 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
133 		pos += 8;
134 	}
135 
136 	/* IEEE80211_RADIOTAP_FLAGS */
137 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
138 		*pos |= IEEE80211_RADIOTAP_F_FCS;
139 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
140 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
141 	if (status->flag & RX_FLAG_SHORTPRE)
142 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
143 	pos++;
144 
145 	/* IEEE80211_RADIOTAP_RATE */
146 	if (!rate || status->flag & RX_FLAG_HT) {
147 		/*
148 		 * Without rate information don't add it. If we have,
149 		 * MCS information is a separate field in radiotap,
150 		 * added below. The byte here is needed as padding
151 		 * for the channel though, so initialise it to 0.
152 		 */
153 		*pos = 0;
154 	} else {
155 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
156 		*pos = rate->bitrate / 5;
157 	}
158 	pos++;
159 
160 	/* IEEE80211_RADIOTAP_CHANNEL */
161 	put_unaligned_le16(status->freq, pos);
162 	pos += 2;
163 	if (status->band == IEEE80211_BAND_5GHZ)
164 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
165 				   pos);
166 	else if (status->flag & RX_FLAG_HT)
167 		put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
168 				   pos);
169 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
170 		put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
171 				   pos);
172 	else if (rate)
173 		put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
174 				   pos);
175 	else
176 		put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
177 	pos += 2;
178 
179 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
180 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
181 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
182 		*pos = status->signal;
183 		rthdr->it_present |=
184 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
185 		pos++;
186 	}
187 
188 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
189 
190 	/* IEEE80211_RADIOTAP_ANTENNA */
191 	*pos = status->antenna;
192 	pos++;
193 
194 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
195 
196 	/* IEEE80211_RADIOTAP_RX_FLAGS */
197 	/* ensure 2 byte alignment for the 2 byte field as required */
198 	if ((pos - (u8 *)rthdr) & 1)
199 		pos++;
200 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
201 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
202 	put_unaligned_le16(rx_flags, pos);
203 	pos += 2;
204 
205 	if (status->flag & RX_FLAG_HT) {
206 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
207 		*pos++ = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
208 			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
209 			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
210 		*pos = 0;
211 		if (status->flag & RX_FLAG_SHORT_GI)
212 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
213 		if (status->flag & RX_FLAG_40MHZ)
214 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
215 		pos++;
216 		*pos++ = status->rate_idx;
217 	}
218 }
219 
220 /*
221  * This function copies a received frame to all monitor interfaces and
222  * returns a cleaned-up SKB that no longer includes the FCS nor the
223  * radiotap header the driver might have added.
224  */
225 static struct sk_buff *
226 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
227 		     struct ieee80211_rate *rate)
228 {
229 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
230 	struct ieee80211_sub_if_data *sdata;
231 	int needed_headroom;
232 	struct sk_buff *skb, *skb2;
233 	struct net_device *prev_dev = NULL;
234 	int present_fcs_len = 0;
235 
236 	/*
237 	 * First, we may need to make a copy of the skb because
238 	 *  (1) we need to modify it for radiotap (if not present), and
239 	 *  (2) the other RX handlers will modify the skb we got.
240 	 *
241 	 * We don't need to, of course, if we aren't going to return
242 	 * the SKB because it has a bad FCS/PLCP checksum.
243 	 */
244 
245 	/* room for the radiotap header based on driver features */
246 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
247 
248 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
249 		present_fcs_len = FCS_LEN;
250 
251 	/* make sure hdr->frame_control is on the linear part */
252 	if (!pskb_may_pull(origskb, 2)) {
253 		dev_kfree_skb(origskb);
254 		return NULL;
255 	}
256 
257 	if (!local->monitors) {
258 		if (should_drop_frame(origskb, present_fcs_len)) {
259 			dev_kfree_skb(origskb);
260 			return NULL;
261 		}
262 
263 		return remove_monitor_info(local, origskb);
264 	}
265 
266 	if (should_drop_frame(origskb, present_fcs_len)) {
267 		/* only need to expand headroom if necessary */
268 		skb = origskb;
269 		origskb = NULL;
270 
271 		/*
272 		 * This shouldn't trigger often because most devices have an
273 		 * RX header they pull before we get here, and that should
274 		 * be big enough for our radiotap information. We should
275 		 * probably export the length to drivers so that we can have
276 		 * them allocate enough headroom to start with.
277 		 */
278 		if (skb_headroom(skb) < needed_headroom &&
279 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
280 			dev_kfree_skb(skb);
281 			return NULL;
282 		}
283 	} else {
284 		/*
285 		 * Need to make a copy and possibly remove radiotap header
286 		 * and FCS from the original.
287 		 */
288 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
289 
290 		origskb = remove_monitor_info(local, origskb);
291 
292 		if (!skb)
293 			return origskb;
294 	}
295 
296 	/* prepend radiotap information */
297 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
298 
299 	skb_reset_mac_header(skb);
300 	skb->ip_summed = CHECKSUM_UNNECESSARY;
301 	skb->pkt_type = PACKET_OTHERHOST;
302 	skb->protocol = htons(ETH_P_802_2);
303 
304 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
305 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
306 			continue;
307 
308 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
309 			continue;
310 
311 		if (!ieee80211_sdata_running(sdata))
312 			continue;
313 
314 		if (prev_dev) {
315 			skb2 = skb_clone(skb, GFP_ATOMIC);
316 			if (skb2) {
317 				skb2->dev = prev_dev;
318 				netif_receive_skb(skb2);
319 			}
320 		}
321 
322 		prev_dev = sdata->dev;
323 		sdata->dev->stats.rx_packets++;
324 		sdata->dev->stats.rx_bytes += skb->len;
325 	}
326 
327 	if (prev_dev) {
328 		skb->dev = prev_dev;
329 		netif_receive_skb(skb);
330 	} else
331 		dev_kfree_skb(skb);
332 
333 	return origskb;
334 }
335 
336 
337 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
338 {
339 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
340 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
341 	int tid, seqno_idx, security_idx;
342 
343 	/* does the frame have a qos control field? */
344 	if (ieee80211_is_data_qos(hdr->frame_control)) {
345 		u8 *qc = ieee80211_get_qos_ctl(hdr);
346 		/* frame has qos control */
347 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
348 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
349 			status->rx_flags |= IEEE80211_RX_AMSDU;
350 
351 		seqno_idx = tid;
352 		security_idx = tid;
353 	} else {
354 		/*
355 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
356 		 *
357 		 *	Sequence numbers for management frames, QoS data
358 		 *	frames with a broadcast/multicast address in the
359 		 *	Address 1 field, and all non-QoS data frames sent
360 		 *	by QoS STAs are assigned using an additional single
361 		 *	modulo-4096 counter, [...]
362 		 *
363 		 * We also use that counter for non-QoS STAs.
364 		 */
365 		seqno_idx = NUM_RX_DATA_QUEUES;
366 		security_idx = 0;
367 		if (ieee80211_is_mgmt(hdr->frame_control))
368 			security_idx = NUM_RX_DATA_QUEUES;
369 		tid = 0;
370 	}
371 
372 	rx->seqno_idx = seqno_idx;
373 	rx->security_idx = security_idx;
374 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
375 	 * For now, set skb->priority to 0 for other cases. */
376 	rx->skb->priority = (tid > 7) ? 0 : tid;
377 }
378 
379 /**
380  * DOC: Packet alignment
381  *
382  * Drivers always need to pass packets that are aligned to two-byte boundaries
383  * to the stack.
384  *
385  * Additionally, should, if possible, align the payload data in a way that
386  * guarantees that the contained IP header is aligned to a four-byte
387  * boundary. In the case of regular frames, this simply means aligning the
388  * payload to a four-byte boundary (because either the IP header is directly
389  * contained, or IV/RFC1042 headers that have a length divisible by four are
390  * in front of it).  If the payload data is not properly aligned and the
391  * architecture doesn't support efficient unaligned operations, mac80211
392  * will align the data.
393  *
394  * With A-MSDU frames, however, the payload data address must yield two modulo
395  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
396  * push the IP header further back to a multiple of four again. Thankfully, the
397  * specs were sane enough this time around to require padding each A-MSDU
398  * subframe to a length that is a multiple of four.
399  *
400  * Padding like Atheros hardware adds which is between the 802.11 header and
401  * the payload is not supported, the driver is required to move the 802.11
402  * header to be directly in front of the payload in that case.
403  */
404 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
405 {
406 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
407 	WARN_ONCE((unsigned long)rx->skb->data & 1,
408 		  "unaligned packet at 0x%p\n", rx->skb->data);
409 #endif
410 }
411 
412 
413 /* rx handlers */
414 
415 static ieee80211_rx_result debug_noinline
416 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
417 {
418 	struct ieee80211_local *local = rx->local;
419 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
420 	struct sk_buff *skb = rx->skb;
421 
422 	if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
423 		   !local->sched_scanning))
424 		return RX_CONTINUE;
425 
426 	if (test_bit(SCAN_HW_SCANNING, &local->scanning) ||
427 	    test_bit(SCAN_SW_SCANNING, &local->scanning) ||
428 	    local->sched_scanning)
429 		return ieee80211_scan_rx(rx->sdata, skb);
430 
431 	/* scanning finished during invoking of handlers */
432 	I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
433 	return RX_DROP_UNUSABLE;
434 }
435 
436 
437 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
438 {
439 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
440 
441 	if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
442 		return 0;
443 
444 	return ieee80211_is_robust_mgmt_frame(hdr);
445 }
446 
447 
448 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
449 {
450 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
451 
452 	if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
453 		return 0;
454 
455 	return ieee80211_is_robust_mgmt_frame(hdr);
456 }
457 
458 
459 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
460 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
461 {
462 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
463 	struct ieee80211_mmie *mmie;
464 
465 	if (skb->len < 24 + sizeof(*mmie) ||
466 	    !is_multicast_ether_addr(hdr->da))
467 		return -1;
468 
469 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
470 		return -1; /* not a robust management frame */
471 
472 	mmie = (struct ieee80211_mmie *)
473 		(skb->data + skb->len - sizeof(*mmie));
474 	if (mmie->element_id != WLAN_EID_MMIE ||
475 	    mmie->length != sizeof(*mmie) - 2)
476 		return -1;
477 
478 	return le16_to_cpu(mmie->key_id);
479 }
480 
481 
482 static ieee80211_rx_result
483 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
484 {
485 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
486 	char *dev_addr = rx->sdata->vif.addr;
487 
488 	if (ieee80211_is_data(hdr->frame_control)) {
489 		if (is_multicast_ether_addr(hdr->addr1)) {
490 			if (ieee80211_has_tods(hdr->frame_control) ||
491 				!ieee80211_has_fromds(hdr->frame_control))
492 				return RX_DROP_MONITOR;
493 			if (compare_ether_addr(hdr->addr3, dev_addr) == 0)
494 				return RX_DROP_MONITOR;
495 		} else {
496 			if (!ieee80211_has_a4(hdr->frame_control))
497 				return RX_DROP_MONITOR;
498 			if (compare_ether_addr(hdr->addr4, dev_addr) == 0)
499 				return RX_DROP_MONITOR;
500 		}
501 	}
502 
503 	/* If there is not an established peer link and this is not a peer link
504 	 * establisment frame, beacon or probe, drop the frame.
505 	 */
506 
507 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
508 		struct ieee80211_mgmt *mgmt;
509 
510 		if (!ieee80211_is_mgmt(hdr->frame_control))
511 			return RX_DROP_MONITOR;
512 
513 		if (ieee80211_is_action(hdr->frame_control)) {
514 			u8 category;
515 			mgmt = (struct ieee80211_mgmt *)hdr;
516 			category = mgmt->u.action.category;
517 			if (category != WLAN_CATEGORY_MESH_ACTION &&
518 				category != WLAN_CATEGORY_SELF_PROTECTED)
519 				return RX_DROP_MONITOR;
520 			return RX_CONTINUE;
521 		}
522 
523 		if (ieee80211_is_probe_req(hdr->frame_control) ||
524 		    ieee80211_is_probe_resp(hdr->frame_control) ||
525 		    ieee80211_is_beacon(hdr->frame_control) ||
526 		    ieee80211_is_auth(hdr->frame_control))
527 			return RX_CONTINUE;
528 
529 		return RX_DROP_MONITOR;
530 
531 	}
532 
533 	return RX_CONTINUE;
534 }
535 
536 #define SEQ_MODULO 0x1000
537 #define SEQ_MASK   0xfff
538 
539 static inline int seq_less(u16 sq1, u16 sq2)
540 {
541 	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
542 }
543 
544 static inline u16 seq_inc(u16 sq)
545 {
546 	return (sq + 1) & SEQ_MASK;
547 }
548 
549 static inline u16 seq_sub(u16 sq1, u16 sq2)
550 {
551 	return (sq1 - sq2) & SEQ_MASK;
552 }
553 
554 
555 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
556 					    struct tid_ampdu_rx *tid_agg_rx,
557 					    int index)
558 {
559 	struct ieee80211_local *local = hw_to_local(hw);
560 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
561 	struct ieee80211_rx_status *status;
562 
563 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
564 
565 	if (!skb)
566 		goto no_frame;
567 
568 	/* release the frame from the reorder ring buffer */
569 	tid_agg_rx->stored_mpdu_num--;
570 	tid_agg_rx->reorder_buf[index] = NULL;
571 	status = IEEE80211_SKB_RXCB(skb);
572 	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
573 	skb_queue_tail(&local->rx_skb_queue, skb);
574 
575 no_frame:
576 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
577 }
578 
579 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
580 					     struct tid_ampdu_rx *tid_agg_rx,
581 					     u16 head_seq_num)
582 {
583 	int index;
584 
585 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
586 
587 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
588 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
589 							tid_agg_rx->buf_size;
590 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
591 	}
592 }
593 
594 /*
595  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
596  * the skb was added to the buffer longer than this time ago, the earlier
597  * frames that have not yet been received are assumed to be lost and the skb
598  * can be released for processing. This may also release other skb's from the
599  * reorder buffer if there are no additional gaps between the frames.
600  *
601  * Callers must hold tid_agg_rx->reorder_lock.
602  */
603 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
604 
605 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
606 					  struct tid_ampdu_rx *tid_agg_rx)
607 {
608 	int index, j;
609 
610 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
611 
612 	/* release the buffer until next missing frame */
613 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
614 						tid_agg_rx->buf_size;
615 	if (!tid_agg_rx->reorder_buf[index] &&
616 	    tid_agg_rx->stored_mpdu_num) {
617 		/*
618 		 * No buffers ready to be released, but check whether any
619 		 * frames in the reorder buffer have timed out.
620 		 */
621 		int skipped = 1;
622 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
623 		     j = (j + 1) % tid_agg_rx->buf_size) {
624 			if (!tid_agg_rx->reorder_buf[j]) {
625 				skipped++;
626 				continue;
627 			}
628 			if (skipped &&
629 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
630 					HT_RX_REORDER_BUF_TIMEOUT))
631 				goto set_release_timer;
632 
633 #ifdef CONFIG_MAC80211_HT_DEBUG
634 			if (net_ratelimit())
635 				wiphy_debug(hw->wiphy,
636 					    "release an RX reorder frame due to timeout on earlier frames\n");
637 #endif
638 			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
639 
640 			/*
641 			 * Increment the head seq# also for the skipped slots.
642 			 */
643 			tid_agg_rx->head_seq_num =
644 				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
645 			skipped = 0;
646 		}
647 	} else while (tid_agg_rx->reorder_buf[index]) {
648 		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
649 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
650 							tid_agg_rx->buf_size;
651 	}
652 
653 	if (tid_agg_rx->stored_mpdu_num) {
654 		j = index = seq_sub(tid_agg_rx->head_seq_num,
655 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
656 
657 		for (; j != (index - 1) % tid_agg_rx->buf_size;
658 		     j = (j + 1) % tid_agg_rx->buf_size) {
659 			if (tid_agg_rx->reorder_buf[j])
660 				break;
661 		}
662 
663  set_release_timer:
664 
665 		mod_timer(&tid_agg_rx->reorder_timer,
666 			  tid_agg_rx->reorder_time[j] + 1 +
667 			  HT_RX_REORDER_BUF_TIMEOUT);
668 	} else {
669 		del_timer(&tid_agg_rx->reorder_timer);
670 	}
671 }
672 
673 /*
674  * As this function belongs to the RX path it must be under
675  * rcu_read_lock protection. It returns false if the frame
676  * can be processed immediately, true if it was consumed.
677  */
678 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
679 					     struct tid_ampdu_rx *tid_agg_rx,
680 					     struct sk_buff *skb)
681 {
682 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
683 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
684 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
685 	u16 head_seq_num, buf_size;
686 	int index;
687 	bool ret = true;
688 
689 	spin_lock(&tid_agg_rx->reorder_lock);
690 
691 	buf_size = tid_agg_rx->buf_size;
692 	head_seq_num = tid_agg_rx->head_seq_num;
693 
694 	/* frame with out of date sequence number */
695 	if (seq_less(mpdu_seq_num, head_seq_num)) {
696 		dev_kfree_skb(skb);
697 		goto out;
698 	}
699 
700 	/*
701 	 * If frame the sequence number exceeds our buffering window
702 	 * size release some previous frames to make room for this one.
703 	 */
704 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
705 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
706 		/* release stored frames up to new head to stack */
707 		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
708 	}
709 
710 	/* Now the new frame is always in the range of the reordering buffer */
711 
712 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
713 
714 	/* check if we already stored this frame */
715 	if (tid_agg_rx->reorder_buf[index]) {
716 		dev_kfree_skb(skb);
717 		goto out;
718 	}
719 
720 	/*
721 	 * If the current MPDU is in the right order and nothing else
722 	 * is stored we can process it directly, no need to buffer it.
723 	 * If it is first but there's something stored, we may be able
724 	 * to release frames after this one.
725 	 */
726 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
727 	    tid_agg_rx->stored_mpdu_num == 0) {
728 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
729 		ret = false;
730 		goto out;
731 	}
732 
733 	/* put the frame in the reordering buffer */
734 	tid_agg_rx->reorder_buf[index] = skb;
735 	tid_agg_rx->reorder_time[index] = jiffies;
736 	tid_agg_rx->stored_mpdu_num++;
737 	ieee80211_sta_reorder_release(hw, tid_agg_rx);
738 
739  out:
740 	spin_unlock(&tid_agg_rx->reorder_lock);
741 	return ret;
742 }
743 
744 /*
745  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
746  * true if the MPDU was buffered, false if it should be processed.
747  */
748 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
749 {
750 	struct sk_buff *skb = rx->skb;
751 	struct ieee80211_local *local = rx->local;
752 	struct ieee80211_hw *hw = &local->hw;
753 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
754 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
755 	struct sta_info *sta = rx->sta;
756 	struct tid_ampdu_rx *tid_agg_rx;
757 	u16 sc;
758 	u8 tid, ack_policy;
759 
760 	if (!ieee80211_is_data_qos(hdr->frame_control))
761 		goto dont_reorder;
762 
763 	/*
764 	 * filter the QoS data rx stream according to
765 	 * STA/TID and check if this STA/TID is on aggregation
766 	 */
767 
768 	if (!sta)
769 		goto dont_reorder;
770 
771 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
772 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
773 	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
774 
775 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
776 	if (!tid_agg_rx)
777 		goto dont_reorder;
778 
779 	/* qos null data frames are excluded */
780 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
781 		goto dont_reorder;
782 
783 	/* not part of a BA session */
784 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
785 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
786 		goto dont_reorder;
787 
788 	/* not actually part of this BA session */
789 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
790 		goto dont_reorder;
791 
792 	/* new, potentially un-ordered, ampdu frame - process it */
793 
794 	/* reset session timer */
795 	if (tid_agg_rx->timeout)
796 		mod_timer(&tid_agg_rx->session_timer,
797 			  TU_TO_EXP_TIME(tid_agg_rx->timeout));
798 
799 	/* if this mpdu is fragmented - terminate rx aggregation session */
800 	sc = le16_to_cpu(hdr->seq_ctrl);
801 	if (sc & IEEE80211_SCTL_FRAG) {
802 		skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
803 		skb_queue_tail(&rx->sdata->skb_queue, skb);
804 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
805 		return;
806 	}
807 
808 	/*
809 	 * No locking needed -- we will only ever process one
810 	 * RX packet at a time, and thus own tid_agg_rx. All
811 	 * other code manipulating it needs to (and does) make
812 	 * sure that we cannot get to it any more before doing
813 	 * anything with it.
814 	 */
815 	if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
816 		return;
817 
818  dont_reorder:
819 	skb_queue_tail(&local->rx_skb_queue, skb);
820 }
821 
822 static ieee80211_rx_result debug_noinline
823 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
824 {
825 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
826 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
827 
828 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
829 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
830 		if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
831 			     rx->sta->last_seq_ctrl[rx->seqno_idx] ==
832 			     hdr->seq_ctrl)) {
833 			if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
834 				rx->local->dot11FrameDuplicateCount++;
835 				rx->sta->num_duplicates++;
836 			}
837 			return RX_DROP_UNUSABLE;
838 		} else
839 			rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
840 	}
841 
842 	if (unlikely(rx->skb->len < 16)) {
843 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
844 		return RX_DROP_MONITOR;
845 	}
846 
847 	/* Drop disallowed frame classes based on STA auth/assoc state;
848 	 * IEEE 802.11, Chap 5.5.
849 	 *
850 	 * mac80211 filters only based on association state, i.e. it drops
851 	 * Class 3 frames from not associated stations. hostapd sends
852 	 * deauth/disassoc frames when needed. In addition, hostapd is
853 	 * responsible for filtering on both auth and assoc states.
854 	 */
855 
856 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
857 		return ieee80211_rx_mesh_check(rx);
858 
859 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
860 		      ieee80211_is_pspoll(hdr->frame_control)) &&
861 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
862 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
863 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
864 		/*
865 		 * accept port control frames from the AP even when it's not
866 		 * yet marked ASSOC to prevent a race where we don't set the
867 		 * assoc bit quickly enough before it sends the first frame
868 		 */
869 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
870 		    ieee80211_is_data_present(hdr->frame_control)) {
871 			u16 ethertype;
872 			u8 *payload;
873 
874 			payload = rx->skb->data +
875 				ieee80211_hdrlen(hdr->frame_control);
876 			ethertype = (payload[6] << 8) | payload[7];
877 			if (cpu_to_be16(ethertype) ==
878 			    rx->sdata->control_port_protocol)
879 				return RX_CONTINUE;
880 		}
881 
882 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
883 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
884 					       hdr->addr2,
885 					       GFP_ATOMIC))
886 			return RX_DROP_UNUSABLE;
887 
888 		return RX_DROP_MONITOR;
889 	}
890 
891 	return RX_CONTINUE;
892 }
893 
894 
895 static ieee80211_rx_result debug_noinline
896 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
897 {
898 	struct sk_buff *skb = rx->skb;
899 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
900 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
901 	int keyidx;
902 	int hdrlen;
903 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
904 	struct ieee80211_key *sta_ptk = NULL;
905 	int mmie_keyidx = -1;
906 	__le16 fc;
907 
908 	/*
909 	 * Key selection 101
910 	 *
911 	 * There are four types of keys:
912 	 *  - GTK (group keys)
913 	 *  - IGTK (group keys for management frames)
914 	 *  - PTK (pairwise keys)
915 	 *  - STK (station-to-station pairwise keys)
916 	 *
917 	 * When selecting a key, we have to distinguish between multicast
918 	 * (including broadcast) and unicast frames, the latter can only
919 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
920 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
921 	 * unicast frames can also use key indices like GTKs. Hence, if we
922 	 * don't have a PTK/STK we check the key index for a WEP key.
923 	 *
924 	 * Note that in a regular BSS, multicast frames are sent by the
925 	 * AP only, associated stations unicast the frame to the AP first
926 	 * which then multicasts it on their behalf.
927 	 *
928 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
929 	 * with each station, that is something we don't currently handle.
930 	 * The spec seems to expect that one negotiates the same key with
931 	 * every station but there's no such requirement; VLANs could be
932 	 * possible.
933 	 */
934 
935 	/*
936 	 * No point in finding a key and decrypting if the frame is neither
937 	 * addressed to us nor a multicast frame.
938 	 */
939 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
940 		return RX_CONTINUE;
941 
942 	/* start without a key */
943 	rx->key = NULL;
944 
945 	if (rx->sta)
946 		sta_ptk = rcu_dereference(rx->sta->ptk);
947 
948 	fc = hdr->frame_control;
949 
950 	if (!ieee80211_has_protected(fc))
951 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
952 
953 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
954 		rx->key = sta_ptk;
955 		if ((status->flag & RX_FLAG_DECRYPTED) &&
956 		    (status->flag & RX_FLAG_IV_STRIPPED))
957 			return RX_CONTINUE;
958 		/* Skip decryption if the frame is not protected. */
959 		if (!ieee80211_has_protected(fc))
960 			return RX_CONTINUE;
961 	} else if (mmie_keyidx >= 0) {
962 		/* Broadcast/multicast robust management frame / BIP */
963 		if ((status->flag & RX_FLAG_DECRYPTED) &&
964 		    (status->flag & RX_FLAG_IV_STRIPPED))
965 			return RX_CONTINUE;
966 
967 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
968 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
969 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
970 		if (rx->sta)
971 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
972 		if (!rx->key)
973 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
974 	} else if (!ieee80211_has_protected(fc)) {
975 		/*
976 		 * The frame was not protected, so skip decryption. However, we
977 		 * need to set rx->key if there is a key that could have been
978 		 * used so that the frame may be dropped if encryption would
979 		 * have been expected.
980 		 */
981 		struct ieee80211_key *key = NULL;
982 		struct ieee80211_sub_if_data *sdata = rx->sdata;
983 		int i;
984 
985 		if (ieee80211_is_mgmt(fc) &&
986 		    is_multicast_ether_addr(hdr->addr1) &&
987 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
988 			rx->key = key;
989 		else {
990 			if (rx->sta) {
991 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
992 					key = rcu_dereference(rx->sta->gtk[i]);
993 					if (key)
994 						break;
995 				}
996 			}
997 			if (!key) {
998 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
999 					key = rcu_dereference(sdata->keys[i]);
1000 					if (key)
1001 						break;
1002 				}
1003 			}
1004 			if (key)
1005 				rx->key = key;
1006 		}
1007 		return RX_CONTINUE;
1008 	} else {
1009 		u8 keyid;
1010 		/*
1011 		 * The device doesn't give us the IV so we won't be
1012 		 * able to look up the key. That's ok though, we
1013 		 * don't need to decrypt the frame, we just won't
1014 		 * be able to keep statistics accurate.
1015 		 * Except for key threshold notifications, should
1016 		 * we somehow allow the driver to tell us which key
1017 		 * the hardware used if this flag is set?
1018 		 */
1019 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1020 		    (status->flag & RX_FLAG_IV_STRIPPED))
1021 			return RX_CONTINUE;
1022 
1023 		hdrlen = ieee80211_hdrlen(fc);
1024 
1025 		if (rx->skb->len < 8 + hdrlen)
1026 			return RX_DROP_UNUSABLE; /* TODO: count this? */
1027 
1028 		/*
1029 		 * no need to call ieee80211_wep_get_keyidx,
1030 		 * it verifies a bunch of things we've done already
1031 		 */
1032 		skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1033 		keyidx = keyid >> 6;
1034 
1035 		/* check per-station GTK first, if multicast packet */
1036 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1037 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1038 
1039 		/* if not found, try default key */
1040 		if (!rx->key) {
1041 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1042 
1043 			/*
1044 			 * RSNA-protected unicast frames should always be
1045 			 * sent with pairwise or station-to-station keys,
1046 			 * but for WEP we allow using a key index as well.
1047 			 */
1048 			if (rx->key &&
1049 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1050 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1051 			    !is_multicast_ether_addr(hdr->addr1))
1052 				rx->key = NULL;
1053 		}
1054 	}
1055 
1056 	if (rx->key) {
1057 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1058 			return RX_DROP_MONITOR;
1059 
1060 		rx->key->tx_rx_count++;
1061 		/* TODO: add threshold stuff again */
1062 	} else {
1063 		return RX_DROP_MONITOR;
1064 	}
1065 
1066 	switch (rx->key->conf.cipher) {
1067 	case WLAN_CIPHER_SUITE_WEP40:
1068 	case WLAN_CIPHER_SUITE_WEP104:
1069 		result = ieee80211_crypto_wep_decrypt(rx);
1070 		break;
1071 	case WLAN_CIPHER_SUITE_TKIP:
1072 		result = ieee80211_crypto_tkip_decrypt(rx);
1073 		break;
1074 	case WLAN_CIPHER_SUITE_CCMP:
1075 		result = ieee80211_crypto_ccmp_decrypt(rx);
1076 		break;
1077 	case WLAN_CIPHER_SUITE_AES_CMAC:
1078 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
1079 		break;
1080 	default:
1081 		/*
1082 		 * We can reach here only with HW-only algorithms
1083 		 * but why didn't it decrypt the frame?!
1084 		 */
1085 		return RX_DROP_UNUSABLE;
1086 	}
1087 
1088 	/* the hdr variable is invalid after the decrypt handlers */
1089 
1090 	/* either the frame has been decrypted or will be dropped */
1091 	status->flag |= RX_FLAG_DECRYPTED;
1092 
1093 	return result;
1094 }
1095 
1096 static ieee80211_rx_result debug_noinline
1097 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1098 {
1099 	struct ieee80211_local *local;
1100 	struct ieee80211_hdr *hdr;
1101 	struct sk_buff *skb;
1102 
1103 	local = rx->local;
1104 	skb = rx->skb;
1105 	hdr = (struct ieee80211_hdr *) skb->data;
1106 
1107 	if (!local->pspolling)
1108 		return RX_CONTINUE;
1109 
1110 	if (!ieee80211_has_fromds(hdr->frame_control))
1111 		/* this is not from AP */
1112 		return RX_CONTINUE;
1113 
1114 	if (!ieee80211_is_data(hdr->frame_control))
1115 		return RX_CONTINUE;
1116 
1117 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1118 		/* AP has no more frames buffered for us */
1119 		local->pspolling = false;
1120 		return RX_CONTINUE;
1121 	}
1122 
1123 	/* more data bit is set, let's request a new frame from the AP */
1124 	ieee80211_send_pspoll(local, rx->sdata);
1125 
1126 	return RX_CONTINUE;
1127 }
1128 
1129 static void ap_sta_ps_start(struct sta_info *sta)
1130 {
1131 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1132 	struct ieee80211_local *local = sdata->local;
1133 
1134 	atomic_inc(&sdata->bss->num_sta_ps);
1135 	set_sta_flag(sta, WLAN_STA_PS_STA);
1136 	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1137 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1138 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1139 	printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1140 	       sdata->name, sta->sta.addr, sta->sta.aid);
1141 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1142 }
1143 
1144 static void ap_sta_ps_end(struct sta_info *sta)
1145 {
1146 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1147 	printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1148 	       sta->sdata->name, sta->sta.addr, sta->sta.aid);
1149 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1150 
1151 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1152 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1153 		printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1154 		       sta->sdata->name, sta->sta.addr, sta->sta.aid);
1155 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1156 		return;
1157 	}
1158 
1159 	ieee80211_sta_ps_deliver_wakeup(sta);
1160 }
1161 
1162 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1163 {
1164 	struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1165 	bool in_ps;
1166 
1167 	WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1168 
1169 	/* Don't let the same PS state be set twice */
1170 	in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1171 	if ((start && in_ps) || (!start && !in_ps))
1172 		return -EINVAL;
1173 
1174 	if (start)
1175 		ap_sta_ps_start(sta_inf);
1176 	else
1177 		ap_sta_ps_end(sta_inf);
1178 
1179 	return 0;
1180 }
1181 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1182 
1183 static ieee80211_rx_result debug_noinline
1184 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1185 {
1186 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1187 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1188 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1189 	int tid, ac;
1190 
1191 	if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1192 		return RX_CONTINUE;
1193 
1194 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1195 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1196 		return RX_CONTINUE;
1197 
1198 	/*
1199 	 * The device handles station powersave, so don't do anything about
1200 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1201 	 * it to mac80211 since they're handled.)
1202 	 */
1203 	if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1204 		return RX_CONTINUE;
1205 
1206 	/*
1207 	 * Don't do anything if the station isn't already asleep. In
1208 	 * the uAPSD case, the station will probably be marked asleep,
1209 	 * in the PS-Poll case the station must be confused ...
1210 	 */
1211 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1212 		return RX_CONTINUE;
1213 
1214 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1215 		if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1216 			if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1217 				ieee80211_sta_ps_deliver_poll_response(rx->sta);
1218 			else
1219 				set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1220 		}
1221 
1222 		/* Free PS Poll skb here instead of returning RX_DROP that would
1223 		 * count as an dropped frame. */
1224 		dev_kfree_skb(rx->skb);
1225 
1226 		return RX_QUEUED;
1227 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1228 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1229 		   ieee80211_has_pm(hdr->frame_control) &&
1230 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1231 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1232 		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1233 		ac = ieee802_1d_to_ac[tid & 7];
1234 
1235 		/*
1236 		 * If this AC is not trigger-enabled do nothing.
1237 		 *
1238 		 * NB: This could/should check a separate bitmap of trigger-
1239 		 * enabled queues, but for now we only implement uAPSD w/o
1240 		 * TSPEC changes to the ACs, so they're always the same.
1241 		 */
1242 		if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1243 			return RX_CONTINUE;
1244 
1245 		/* if we are in a service period, do nothing */
1246 		if (test_sta_flag(rx->sta, WLAN_STA_SP))
1247 			return RX_CONTINUE;
1248 
1249 		if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1250 			ieee80211_sta_ps_deliver_uapsd(rx->sta);
1251 		else
1252 			set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1253 	}
1254 
1255 	return RX_CONTINUE;
1256 }
1257 
1258 static ieee80211_rx_result debug_noinline
1259 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1260 {
1261 	struct sta_info *sta = rx->sta;
1262 	struct sk_buff *skb = rx->skb;
1263 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1264 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1265 
1266 	if (!sta)
1267 		return RX_CONTINUE;
1268 
1269 	/*
1270 	 * Update last_rx only for IBSS packets which are for the current
1271 	 * BSSID to avoid keeping the current IBSS network alive in cases
1272 	 * where other STAs start using different BSSID.
1273 	 */
1274 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1275 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1276 						NL80211_IFTYPE_ADHOC);
1277 		if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) {
1278 			sta->last_rx = jiffies;
1279 			if (ieee80211_is_data(hdr->frame_control)) {
1280 				sta->last_rx_rate_idx = status->rate_idx;
1281 				sta->last_rx_rate_flag = status->flag;
1282 			}
1283 		}
1284 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1285 		/*
1286 		 * Mesh beacons will update last_rx when if they are found to
1287 		 * match the current local configuration when processed.
1288 		 */
1289 		sta->last_rx = jiffies;
1290 		if (ieee80211_is_data(hdr->frame_control)) {
1291 			sta->last_rx_rate_idx = status->rate_idx;
1292 			sta->last_rx_rate_flag = status->flag;
1293 		}
1294 	}
1295 
1296 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1297 		return RX_CONTINUE;
1298 
1299 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1300 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1301 
1302 	sta->rx_fragments++;
1303 	sta->rx_bytes += rx->skb->len;
1304 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1305 		sta->last_signal = status->signal;
1306 		ewma_add(&sta->avg_signal, -status->signal);
1307 	}
1308 
1309 	/*
1310 	 * Change STA power saving mode only at the end of a frame
1311 	 * exchange sequence.
1312 	 */
1313 	if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1314 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1315 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1316 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1317 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1318 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1319 			/*
1320 			 * Ignore doze->wake transitions that are
1321 			 * indicated by non-data frames, the standard
1322 			 * is unclear here, but for example going to
1323 			 * PS mode and then scanning would cause a
1324 			 * doze->wake transition for the probe request,
1325 			 * and that is clearly undesirable.
1326 			 */
1327 			if (ieee80211_is_data(hdr->frame_control) &&
1328 			    !ieee80211_has_pm(hdr->frame_control))
1329 				ap_sta_ps_end(sta);
1330 		} else {
1331 			if (ieee80211_has_pm(hdr->frame_control))
1332 				ap_sta_ps_start(sta);
1333 		}
1334 	}
1335 
1336 	/*
1337 	 * Drop (qos-)data::nullfunc frames silently, since they
1338 	 * are used only to control station power saving mode.
1339 	 */
1340 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1341 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1342 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1343 
1344 		/*
1345 		 * If we receive a 4-addr nullfunc frame from a STA
1346 		 * that was not moved to a 4-addr STA vlan yet send
1347 		 * the event to userspace and for older hostapd drop
1348 		 * the frame to the monitor interface.
1349 		 */
1350 		if (ieee80211_has_a4(hdr->frame_control) &&
1351 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1352 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1353 		      !rx->sdata->u.vlan.sta))) {
1354 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1355 				cfg80211_rx_unexpected_4addr_frame(
1356 					rx->sdata->dev, sta->sta.addr,
1357 					GFP_ATOMIC);
1358 			return RX_DROP_MONITOR;
1359 		}
1360 		/*
1361 		 * Update counter and free packet here to avoid
1362 		 * counting this as a dropped packed.
1363 		 */
1364 		sta->rx_packets++;
1365 		dev_kfree_skb(rx->skb);
1366 		return RX_QUEUED;
1367 	}
1368 
1369 	return RX_CONTINUE;
1370 } /* ieee80211_rx_h_sta_process */
1371 
1372 static inline struct ieee80211_fragment_entry *
1373 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1374 			 unsigned int frag, unsigned int seq, int rx_queue,
1375 			 struct sk_buff **skb)
1376 {
1377 	struct ieee80211_fragment_entry *entry;
1378 	int idx;
1379 
1380 	idx = sdata->fragment_next;
1381 	entry = &sdata->fragments[sdata->fragment_next++];
1382 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1383 		sdata->fragment_next = 0;
1384 
1385 	if (!skb_queue_empty(&entry->skb_list)) {
1386 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1387 		struct ieee80211_hdr *hdr =
1388 			(struct ieee80211_hdr *) entry->skb_list.next->data;
1389 		printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1390 		       "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1391 		       "addr1=%pM addr2=%pM\n",
1392 		       sdata->name, idx,
1393 		       jiffies - entry->first_frag_time, entry->seq,
1394 		       entry->last_frag, hdr->addr1, hdr->addr2);
1395 #endif
1396 		__skb_queue_purge(&entry->skb_list);
1397 	}
1398 
1399 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1400 	*skb = NULL;
1401 	entry->first_frag_time = jiffies;
1402 	entry->seq = seq;
1403 	entry->rx_queue = rx_queue;
1404 	entry->last_frag = frag;
1405 	entry->ccmp = 0;
1406 	entry->extra_len = 0;
1407 
1408 	return entry;
1409 }
1410 
1411 static inline struct ieee80211_fragment_entry *
1412 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1413 			  unsigned int frag, unsigned int seq,
1414 			  int rx_queue, struct ieee80211_hdr *hdr)
1415 {
1416 	struct ieee80211_fragment_entry *entry;
1417 	int i, idx;
1418 
1419 	idx = sdata->fragment_next;
1420 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1421 		struct ieee80211_hdr *f_hdr;
1422 
1423 		idx--;
1424 		if (idx < 0)
1425 			idx = IEEE80211_FRAGMENT_MAX - 1;
1426 
1427 		entry = &sdata->fragments[idx];
1428 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1429 		    entry->rx_queue != rx_queue ||
1430 		    entry->last_frag + 1 != frag)
1431 			continue;
1432 
1433 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1434 
1435 		/*
1436 		 * Check ftype and addresses are equal, else check next fragment
1437 		 */
1438 		if (((hdr->frame_control ^ f_hdr->frame_control) &
1439 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1440 		    compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1441 		    compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1442 			continue;
1443 
1444 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1445 			__skb_queue_purge(&entry->skb_list);
1446 			continue;
1447 		}
1448 		return entry;
1449 	}
1450 
1451 	return NULL;
1452 }
1453 
1454 static ieee80211_rx_result debug_noinline
1455 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1456 {
1457 	struct ieee80211_hdr *hdr;
1458 	u16 sc;
1459 	__le16 fc;
1460 	unsigned int frag, seq;
1461 	struct ieee80211_fragment_entry *entry;
1462 	struct sk_buff *skb;
1463 	struct ieee80211_rx_status *status;
1464 
1465 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1466 	fc = hdr->frame_control;
1467 	sc = le16_to_cpu(hdr->seq_ctrl);
1468 	frag = sc & IEEE80211_SCTL_FRAG;
1469 
1470 	if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1471 		   (rx->skb)->len < 24 ||
1472 		   is_multicast_ether_addr(hdr->addr1))) {
1473 		/* not fragmented */
1474 		goto out;
1475 	}
1476 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1477 
1478 	if (skb_linearize(rx->skb))
1479 		return RX_DROP_UNUSABLE;
1480 
1481 	/*
1482 	 *  skb_linearize() might change the skb->data and
1483 	 *  previously cached variables (in this case, hdr) need to
1484 	 *  be refreshed with the new data.
1485 	 */
1486 	hdr = (struct ieee80211_hdr *)rx->skb->data;
1487 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1488 
1489 	if (frag == 0) {
1490 		/* This is the first fragment of a new frame. */
1491 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1492 						 rx->seqno_idx, &(rx->skb));
1493 		if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1494 		    ieee80211_has_protected(fc)) {
1495 			int queue = rx->security_idx;
1496 			/* Store CCMP PN so that we can verify that the next
1497 			 * fragment has a sequential PN value. */
1498 			entry->ccmp = 1;
1499 			memcpy(entry->last_pn,
1500 			       rx->key->u.ccmp.rx_pn[queue],
1501 			       CCMP_PN_LEN);
1502 		}
1503 		return RX_QUEUED;
1504 	}
1505 
1506 	/* This is a fragment for a frame that should already be pending in
1507 	 * fragment cache. Add this fragment to the end of the pending entry.
1508 	 */
1509 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1510 					  rx->seqno_idx, hdr);
1511 	if (!entry) {
1512 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1513 		return RX_DROP_MONITOR;
1514 	}
1515 
1516 	/* Verify that MPDUs within one MSDU have sequential PN values.
1517 	 * (IEEE 802.11i, 8.3.3.4.5) */
1518 	if (entry->ccmp) {
1519 		int i;
1520 		u8 pn[CCMP_PN_LEN], *rpn;
1521 		int queue;
1522 		if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1523 			return RX_DROP_UNUSABLE;
1524 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1525 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1526 			pn[i]++;
1527 			if (pn[i])
1528 				break;
1529 		}
1530 		queue = rx->security_idx;
1531 		rpn = rx->key->u.ccmp.rx_pn[queue];
1532 		if (memcmp(pn, rpn, CCMP_PN_LEN))
1533 			return RX_DROP_UNUSABLE;
1534 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1535 	}
1536 
1537 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
1538 	__skb_queue_tail(&entry->skb_list, rx->skb);
1539 	entry->last_frag = frag;
1540 	entry->extra_len += rx->skb->len;
1541 	if (ieee80211_has_morefrags(fc)) {
1542 		rx->skb = NULL;
1543 		return RX_QUEUED;
1544 	}
1545 
1546 	rx->skb = __skb_dequeue(&entry->skb_list);
1547 	if (skb_tailroom(rx->skb) < entry->extra_len) {
1548 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1549 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1550 					      GFP_ATOMIC))) {
1551 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1552 			__skb_queue_purge(&entry->skb_list);
1553 			return RX_DROP_UNUSABLE;
1554 		}
1555 	}
1556 	while ((skb = __skb_dequeue(&entry->skb_list))) {
1557 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1558 		dev_kfree_skb(skb);
1559 	}
1560 
1561 	/* Complete frame has been reassembled - process it now */
1562 	status = IEEE80211_SKB_RXCB(rx->skb);
1563 	status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1564 
1565  out:
1566 	if (rx->sta)
1567 		rx->sta->rx_packets++;
1568 	if (is_multicast_ether_addr(hdr->addr1))
1569 		rx->local->dot11MulticastReceivedFrameCount++;
1570 	else
1571 		ieee80211_led_rx(rx->local);
1572 	return RX_CONTINUE;
1573 }
1574 
1575 static int
1576 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1577 {
1578 	if (unlikely(!rx->sta ||
1579 	    !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1580 		return -EACCES;
1581 
1582 	return 0;
1583 }
1584 
1585 static int
1586 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1587 {
1588 	struct sk_buff *skb = rx->skb;
1589 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1590 
1591 	/*
1592 	 * Pass through unencrypted frames if the hardware has
1593 	 * decrypted them already.
1594 	 */
1595 	if (status->flag & RX_FLAG_DECRYPTED)
1596 		return 0;
1597 
1598 	/* Drop unencrypted frames if key is set. */
1599 	if (unlikely(!ieee80211_has_protected(fc) &&
1600 		     !ieee80211_is_nullfunc(fc) &&
1601 		     ieee80211_is_data(fc) &&
1602 		     (rx->key || rx->sdata->drop_unencrypted)))
1603 		return -EACCES;
1604 
1605 	return 0;
1606 }
1607 
1608 static int
1609 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1610 {
1611 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1612 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1613 	__le16 fc = hdr->frame_control;
1614 
1615 	/*
1616 	 * Pass through unencrypted frames if the hardware has
1617 	 * decrypted them already.
1618 	 */
1619 	if (status->flag & RX_FLAG_DECRYPTED)
1620 		return 0;
1621 
1622 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1623 		if (unlikely(!ieee80211_has_protected(fc) &&
1624 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1625 			     rx->key)) {
1626 			if (ieee80211_is_deauth(fc))
1627 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1628 							    rx->skb->data,
1629 							    rx->skb->len);
1630 			else if (ieee80211_is_disassoc(fc))
1631 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1632 							      rx->skb->data,
1633 							      rx->skb->len);
1634 			return -EACCES;
1635 		}
1636 		/* BIP does not use Protected field, so need to check MMIE */
1637 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1638 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1639 			if (ieee80211_is_deauth(fc))
1640 				cfg80211_send_unprot_deauth(rx->sdata->dev,
1641 							    rx->skb->data,
1642 							    rx->skb->len);
1643 			else if (ieee80211_is_disassoc(fc))
1644 				cfg80211_send_unprot_disassoc(rx->sdata->dev,
1645 							      rx->skb->data,
1646 							      rx->skb->len);
1647 			return -EACCES;
1648 		}
1649 		/*
1650 		 * When using MFP, Action frames are not allowed prior to
1651 		 * having configured keys.
1652 		 */
1653 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1654 			     ieee80211_is_robust_mgmt_frame(
1655 				     (struct ieee80211_hdr *) rx->skb->data)))
1656 			return -EACCES;
1657 	}
1658 
1659 	return 0;
1660 }
1661 
1662 static int
1663 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1664 {
1665 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1666 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1667 	bool check_port_control = false;
1668 	struct ethhdr *ehdr;
1669 	int ret;
1670 
1671 	*port_control = false;
1672 	if (ieee80211_has_a4(hdr->frame_control) &&
1673 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1674 		return -1;
1675 
1676 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1677 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1678 
1679 		if (!sdata->u.mgd.use_4addr)
1680 			return -1;
1681 		else
1682 			check_port_control = true;
1683 	}
1684 
1685 	if (is_multicast_ether_addr(hdr->addr1) &&
1686 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1687 		return -1;
1688 
1689 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1690 	if (ret < 0)
1691 		return ret;
1692 
1693 	ehdr = (struct ethhdr *) rx->skb->data;
1694 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
1695 		*port_control = true;
1696 	else if (check_port_control)
1697 		return -1;
1698 
1699 	return 0;
1700 }
1701 
1702 /*
1703  * requires that rx->skb is a frame with ethernet header
1704  */
1705 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1706 {
1707 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1708 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1709 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1710 
1711 	/*
1712 	 * Allow EAPOL frames to us/the PAE group address regardless
1713 	 * of whether the frame was encrypted or not.
1714 	 */
1715 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1716 	    (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1717 	     compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1718 		return true;
1719 
1720 	if (ieee80211_802_1x_port_control(rx) ||
1721 	    ieee80211_drop_unencrypted(rx, fc))
1722 		return false;
1723 
1724 	return true;
1725 }
1726 
1727 /*
1728  * requires that rx->skb is a frame with ethernet header
1729  */
1730 static void
1731 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1732 {
1733 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1734 	struct net_device *dev = sdata->dev;
1735 	struct sk_buff *skb, *xmit_skb;
1736 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1737 	struct sta_info *dsta;
1738 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1739 
1740 	skb = rx->skb;
1741 	xmit_skb = NULL;
1742 
1743 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1744 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1745 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1746 	    (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1747 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1748 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1749 			/*
1750 			 * send multicast frames both to higher layers in
1751 			 * local net stack and back to the wireless medium
1752 			 */
1753 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1754 			if (!xmit_skb && net_ratelimit())
1755 				printk(KERN_DEBUG "%s: failed to clone "
1756 				       "multicast frame\n", dev->name);
1757 		} else {
1758 			dsta = sta_info_get(sdata, skb->data);
1759 			if (dsta) {
1760 				/*
1761 				 * The destination station is associated to
1762 				 * this AP (in this VLAN), so send the frame
1763 				 * directly to it and do not pass it to local
1764 				 * net stack.
1765 				 */
1766 				xmit_skb = skb;
1767 				skb = NULL;
1768 			}
1769 		}
1770 	}
1771 
1772 	if (skb) {
1773 		int align __maybe_unused;
1774 
1775 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1776 		/*
1777 		 * 'align' will only take the values 0 or 2 here
1778 		 * since all frames are required to be aligned
1779 		 * to 2-byte boundaries when being passed to
1780 		 * mac80211. That also explains the __skb_push()
1781 		 * below.
1782 		 */
1783 		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1784 		if (align) {
1785 			if (WARN_ON(skb_headroom(skb) < 3)) {
1786 				dev_kfree_skb(skb);
1787 				skb = NULL;
1788 			} else {
1789 				u8 *data = skb->data;
1790 				size_t len = skb_headlen(skb);
1791 				skb->data -= align;
1792 				memmove(skb->data, data, len);
1793 				skb_set_tail_pointer(skb, len);
1794 			}
1795 		}
1796 #endif
1797 
1798 		if (skb) {
1799 			/* deliver to local stack */
1800 			skb->protocol = eth_type_trans(skb, dev);
1801 			memset(skb->cb, 0, sizeof(skb->cb));
1802 			netif_receive_skb(skb);
1803 		}
1804 	}
1805 
1806 	if (xmit_skb) {
1807 		/*
1808 		 * Send to wireless media and increase priority by 256 to
1809 		 * keep the received priority instead of reclassifying
1810 		 * the frame (see cfg80211_classify8021d).
1811 		 */
1812 		xmit_skb->priority += 256;
1813 		xmit_skb->protocol = htons(ETH_P_802_3);
1814 		skb_reset_network_header(xmit_skb);
1815 		skb_reset_mac_header(xmit_skb);
1816 		dev_queue_xmit(xmit_skb);
1817 	}
1818 }
1819 
1820 static ieee80211_rx_result debug_noinline
1821 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1822 {
1823 	struct net_device *dev = rx->sdata->dev;
1824 	struct sk_buff *skb = rx->skb;
1825 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1826 	__le16 fc = hdr->frame_control;
1827 	struct sk_buff_head frame_list;
1828 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1829 
1830 	if (unlikely(!ieee80211_is_data(fc)))
1831 		return RX_CONTINUE;
1832 
1833 	if (unlikely(!ieee80211_is_data_present(fc)))
1834 		return RX_DROP_MONITOR;
1835 
1836 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1837 		return RX_CONTINUE;
1838 
1839 	if (ieee80211_has_a4(hdr->frame_control) &&
1840 	    rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1841 	    !rx->sdata->u.vlan.sta)
1842 		return RX_DROP_UNUSABLE;
1843 
1844 	if (is_multicast_ether_addr(hdr->addr1) &&
1845 	    ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1846 	      rx->sdata->u.vlan.sta) ||
1847 	     (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1848 	      rx->sdata->u.mgd.use_4addr)))
1849 		return RX_DROP_UNUSABLE;
1850 
1851 	skb->dev = dev;
1852 	__skb_queue_head_init(&frame_list);
1853 
1854 	if (skb_linearize(skb))
1855 		return RX_DROP_UNUSABLE;
1856 
1857 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1858 				 rx->sdata->vif.type,
1859 				 rx->local->hw.extra_tx_headroom, true);
1860 
1861 	while (!skb_queue_empty(&frame_list)) {
1862 		rx->skb = __skb_dequeue(&frame_list);
1863 
1864 		if (!ieee80211_frame_allowed(rx, fc)) {
1865 			dev_kfree_skb(rx->skb);
1866 			continue;
1867 		}
1868 		dev->stats.rx_packets++;
1869 		dev->stats.rx_bytes += rx->skb->len;
1870 
1871 		ieee80211_deliver_skb(rx);
1872 	}
1873 
1874 	return RX_QUEUED;
1875 }
1876 
1877 #ifdef CONFIG_MAC80211_MESH
1878 static ieee80211_rx_result
1879 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1880 {
1881 	struct ieee80211_hdr *fwd_hdr, *hdr;
1882 	struct ieee80211_tx_info *info;
1883 	struct ieee80211s_hdr *mesh_hdr;
1884 	struct sk_buff *skb = rx->skb, *fwd_skb;
1885 	struct ieee80211_local *local = rx->local;
1886 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1887 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1888 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1889 	__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1890 	u16 q, hdrlen;
1891 
1892 	hdr = (struct ieee80211_hdr *) skb->data;
1893 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1894 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1895 
1896 	/* frame is in RMC, don't forward */
1897 	if (ieee80211_is_data(hdr->frame_control) &&
1898 	    is_multicast_ether_addr(hdr->addr1) &&
1899 	    mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1900 		return RX_DROP_MONITOR;
1901 
1902 	if (!ieee80211_is_data(hdr->frame_control))
1903 		return RX_CONTINUE;
1904 
1905 	if (!mesh_hdr->ttl)
1906 		return RX_DROP_MONITOR;
1907 
1908 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
1909 		struct mesh_path *mppath;
1910 		char *proxied_addr;
1911 		char *mpp_addr;
1912 
1913 		if (is_multicast_ether_addr(hdr->addr1)) {
1914 			mpp_addr = hdr->addr3;
1915 			proxied_addr = mesh_hdr->eaddr1;
1916 		} else {
1917 			mpp_addr = hdr->addr4;
1918 			proxied_addr = mesh_hdr->eaddr2;
1919 		}
1920 
1921 		rcu_read_lock();
1922 		mppath = mpp_path_lookup(proxied_addr, sdata);
1923 		if (!mppath) {
1924 			mpp_path_add(proxied_addr, mpp_addr, sdata);
1925 		} else {
1926 			spin_lock_bh(&mppath->state_lock);
1927 			if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1928 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1929 			spin_unlock_bh(&mppath->state_lock);
1930 		}
1931 		rcu_read_unlock();
1932 	}
1933 
1934 	/* Frame has reached destination.  Don't forward */
1935 	if (!is_multicast_ether_addr(hdr->addr1) &&
1936 	    compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1937 		return RX_CONTINUE;
1938 
1939 	q = ieee80211_select_queue_80211(local, skb, hdr);
1940 	if (ieee80211_queue_stopped(&local->hw, q)) {
1941 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1942 		return RX_DROP_MONITOR;
1943 	}
1944 	skb_set_queue_mapping(skb, q);
1945 
1946 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1947 		goto out;
1948 
1949 	if (!--mesh_hdr->ttl) {
1950 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1951 		return RX_DROP_MONITOR;
1952 	}
1953 
1954 	if (!ifmsh->mshcfg.dot11MeshForwarding)
1955 		goto out;
1956 
1957 	fwd_skb = skb_copy(skb, GFP_ATOMIC);
1958 	if (!fwd_skb) {
1959 		if (net_ratelimit())
1960 			printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1961 					sdata->name);
1962 		goto out;
1963 	}
1964 
1965 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1966 	info = IEEE80211_SKB_CB(fwd_skb);
1967 	memset(info, 0, sizeof(*info));
1968 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1969 	info->control.vif = &rx->sdata->vif;
1970 	info->control.jiffies = jiffies;
1971 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1972 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1973 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1974 	} else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1975 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1976 	} else {
1977 		/* unable to resolve next hop */
1978 		mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
1979 				    0, reason, fwd_hdr->addr2, sdata);
1980 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
1981 		kfree_skb(fwd_skb);
1982 		return RX_DROP_MONITOR;
1983 	}
1984 
1985 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
1986 	ieee80211_add_pending_skb(local, fwd_skb);
1987  out:
1988 	if (is_multicast_ether_addr(hdr->addr1) ||
1989 	    sdata->dev->flags & IFF_PROMISC)
1990 		return RX_CONTINUE;
1991 	else
1992 		return RX_DROP_MONITOR;
1993 }
1994 #endif
1995 
1996 static ieee80211_rx_result debug_noinline
1997 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1998 {
1999 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2000 	struct ieee80211_local *local = rx->local;
2001 	struct net_device *dev = sdata->dev;
2002 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2003 	__le16 fc = hdr->frame_control;
2004 	bool port_control;
2005 	int err;
2006 
2007 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2008 		return RX_CONTINUE;
2009 
2010 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2011 		return RX_DROP_MONITOR;
2012 
2013 	/*
2014 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2015 	 * also drop the frame to cooked monitor interfaces.
2016 	 */
2017 	if (ieee80211_has_a4(hdr->frame_control) &&
2018 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2019 		if (rx->sta &&
2020 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2021 			cfg80211_rx_unexpected_4addr_frame(
2022 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2023 		return RX_DROP_MONITOR;
2024 	}
2025 
2026 	err = __ieee80211_data_to_8023(rx, &port_control);
2027 	if (unlikely(err))
2028 		return RX_DROP_UNUSABLE;
2029 
2030 	if (!ieee80211_frame_allowed(rx, fc))
2031 		return RX_DROP_MONITOR;
2032 
2033 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2034 	    unlikely(port_control) && sdata->bss) {
2035 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2036 				     u.ap);
2037 		dev = sdata->dev;
2038 		rx->sdata = sdata;
2039 	}
2040 
2041 	rx->skb->dev = dev;
2042 
2043 	dev->stats.rx_packets++;
2044 	dev->stats.rx_bytes += rx->skb->len;
2045 
2046 	if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2047 	    !is_multicast_ether_addr(
2048 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2049 	    (!local->scanning &&
2050 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2051 			mod_timer(&local->dynamic_ps_timer, jiffies +
2052 			 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2053 	}
2054 
2055 	ieee80211_deliver_skb(rx);
2056 
2057 	return RX_QUEUED;
2058 }
2059 
2060 static ieee80211_rx_result debug_noinline
2061 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2062 {
2063 	struct ieee80211_local *local = rx->local;
2064 	struct ieee80211_hw *hw = &local->hw;
2065 	struct sk_buff *skb = rx->skb;
2066 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2067 	struct tid_ampdu_rx *tid_agg_rx;
2068 	u16 start_seq_num;
2069 	u16 tid;
2070 
2071 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2072 		return RX_CONTINUE;
2073 
2074 	if (ieee80211_is_back_req(bar->frame_control)) {
2075 		struct {
2076 			__le16 control, start_seq_num;
2077 		} __packed bar_data;
2078 
2079 		if (!rx->sta)
2080 			return RX_DROP_MONITOR;
2081 
2082 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2083 				  &bar_data, sizeof(bar_data)))
2084 			return RX_DROP_MONITOR;
2085 
2086 		tid = le16_to_cpu(bar_data.control) >> 12;
2087 
2088 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2089 		if (!tid_agg_rx)
2090 			return RX_DROP_MONITOR;
2091 
2092 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2093 
2094 		/* reset session timer */
2095 		if (tid_agg_rx->timeout)
2096 			mod_timer(&tid_agg_rx->session_timer,
2097 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2098 
2099 		spin_lock(&tid_agg_rx->reorder_lock);
2100 		/* release stored frames up to start of BAR */
2101 		ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
2102 		spin_unlock(&tid_agg_rx->reorder_lock);
2103 
2104 		kfree_skb(skb);
2105 		return RX_QUEUED;
2106 	}
2107 
2108 	/*
2109 	 * After this point, we only want management frames,
2110 	 * so we can drop all remaining control frames to
2111 	 * cooked monitor interfaces.
2112 	 */
2113 	return RX_DROP_MONITOR;
2114 }
2115 
2116 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2117 					   struct ieee80211_mgmt *mgmt,
2118 					   size_t len)
2119 {
2120 	struct ieee80211_local *local = sdata->local;
2121 	struct sk_buff *skb;
2122 	struct ieee80211_mgmt *resp;
2123 
2124 	if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
2125 		/* Not to own unicast address */
2126 		return;
2127 	}
2128 
2129 	if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
2130 	    compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
2131 		/* Not from the current AP or not associated yet. */
2132 		return;
2133 	}
2134 
2135 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2136 		/* Too short SA Query request frame */
2137 		return;
2138 	}
2139 
2140 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2141 	if (skb == NULL)
2142 		return;
2143 
2144 	skb_reserve(skb, local->hw.extra_tx_headroom);
2145 	resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2146 	memset(resp, 0, 24);
2147 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2148 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2149 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2150 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2151 					  IEEE80211_STYPE_ACTION);
2152 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2153 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2154 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2155 	memcpy(resp->u.action.u.sa_query.trans_id,
2156 	       mgmt->u.action.u.sa_query.trans_id,
2157 	       WLAN_SA_QUERY_TR_ID_LEN);
2158 
2159 	ieee80211_tx_skb(sdata, skb);
2160 }
2161 
2162 static ieee80211_rx_result debug_noinline
2163 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2164 {
2165 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2166 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2167 
2168 	/*
2169 	 * From here on, look only at management frames.
2170 	 * Data and control frames are already handled,
2171 	 * and unknown (reserved) frames are useless.
2172 	 */
2173 	if (rx->skb->len < 24)
2174 		return RX_DROP_MONITOR;
2175 
2176 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2177 		return RX_DROP_MONITOR;
2178 
2179 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2180 	    ieee80211_is_beacon(mgmt->frame_control) &&
2181 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2182 		int sig = 0;
2183 
2184 		if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2185 			sig = status->signal;
2186 
2187 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2188 					    rx->skb->data, rx->skb->len,
2189 					    status->freq, sig, GFP_ATOMIC);
2190 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2191 	}
2192 
2193 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2194 		return RX_DROP_MONITOR;
2195 
2196 	if (ieee80211_drop_unencrypted_mgmt(rx))
2197 		return RX_DROP_UNUSABLE;
2198 
2199 	return RX_CONTINUE;
2200 }
2201 
2202 static ieee80211_rx_result debug_noinline
2203 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2204 {
2205 	struct ieee80211_local *local = rx->local;
2206 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2207 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2208 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2209 	int len = rx->skb->len;
2210 
2211 	if (!ieee80211_is_action(mgmt->frame_control))
2212 		return RX_CONTINUE;
2213 
2214 	/* drop too small frames */
2215 	if (len < IEEE80211_MIN_ACTION_SIZE)
2216 		return RX_DROP_UNUSABLE;
2217 
2218 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2219 		return RX_DROP_UNUSABLE;
2220 
2221 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2222 		return RX_DROP_UNUSABLE;
2223 
2224 	switch (mgmt->u.action.category) {
2225 	case WLAN_CATEGORY_HT:
2226 		/* reject HT action frames from stations not supporting HT */
2227 		if (!rx->sta->sta.ht_cap.ht_supported)
2228 			goto invalid;
2229 
2230 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2231 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2232 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2233 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2234 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2235 			break;
2236 
2237 		/* verify action & smps_control are present */
2238 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2239 			goto invalid;
2240 
2241 		switch (mgmt->u.action.u.ht_smps.action) {
2242 		case WLAN_HT_ACTION_SMPS: {
2243 			struct ieee80211_supported_band *sband;
2244 			u8 smps;
2245 
2246 			/* convert to HT capability */
2247 			switch (mgmt->u.action.u.ht_smps.smps_control) {
2248 			case WLAN_HT_SMPS_CONTROL_DISABLED:
2249 				smps = WLAN_HT_CAP_SM_PS_DISABLED;
2250 				break;
2251 			case WLAN_HT_SMPS_CONTROL_STATIC:
2252 				smps = WLAN_HT_CAP_SM_PS_STATIC;
2253 				break;
2254 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2255 				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2256 				break;
2257 			default:
2258 				goto invalid;
2259 			}
2260 			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2261 
2262 			/* if no change do nothing */
2263 			if ((rx->sta->sta.ht_cap.cap &
2264 					IEEE80211_HT_CAP_SM_PS) == smps)
2265 				goto handled;
2266 
2267 			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2268 			rx->sta->sta.ht_cap.cap |= smps;
2269 
2270 			sband = rx->local->hw.wiphy->bands[status->band];
2271 
2272 			rate_control_rate_update(
2273 				local, sband, rx->sta,
2274 				IEEE80211_RC_SMPS_CHANGED,
2275 				ieee80211_get_tx_channel_type(
2276 					local, local->_oper_channel_type));
2277 			goto handled;
2278 		}
2279 		default:
2280 			goto invalid;
2281 		}
2282 
2283 		break;
2284 	case WLAN_CATEGORY_BACK:
2285 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2286 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2287 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2288 		    sdata->vif.type != NL80211_IFTYPE_AP &&
2289 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
2290 			break;
2291 
2292 		/* verify action_code is present */
2293 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2294 			break;
2295 
2296 		switch (mgmt->u.action.u.addba_req.action_code) {
2297 		case WLAN_ACTION_ADDBA_REQ:
2298 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2299 				   sizeof(mgmt->u.action.u.addba_req)))
2300 				goto invalid;
2301 			break;
2302 		case WLAN_ACTION_ADDBA_RESP:
2303 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2304 				   sizeof(mgmt->u.action.u.addba_resp)))
2305 				goto invalid;
2306 			break;
2307 		case WLAN_ACTION_DELBA:
2308 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2309 				   sizeof(mgmt->u.action.u.delba)))
2310 				goto invalid;
2311 			break;
2312 		default:
2313 			goto invalid;
2314 		}
2315 
2316 		goto queue;
2317 	case WLAN_CATEGORY_SPECTRUM_MGMT:
2318 		if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2319 			break;
2320 
2321 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2322 			break;
2323 
2324 		/* verify action_code is present */
2325 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2326 			break;
2327 
2328 		switch (mgmt->u.action.u.measurement.action_code) {
2329 		case WLAN_ACTION_SPCT_MSR_REQ:
2330 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2331 				   sizeof(mgmt->u.action.u.measurement)))
2332 				break;
2333 			ieee80211_process_measurement_req(sdata, mgmt, len);
2334 			goto handled;
2335 		case WLAN_ACTION_SPCT_CHL_SWITCH:
2336 			if (len < (IEEE80211_MIN_ACTION_SIZE +
2337 				   sizeof(mgmt->u.action.u.chan_switch)))
2338 				break;
2339 
2340 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2341 				break;
2342 
2343 			if (compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid))
2344 				break;
2345 
2346 			goto queue;
2347 		}
2348 		break;
2349 	case WLAN_CATEGORY_SA_QUERY:
2350 		if (len < (IEEE80211_MIN_ACTION_SIZE +
2351 			   sizeof(mgmt->u.action.u.sa_query)))
2352 			break;
2353 
2354 		switch (mgmt->u.action.u.sa_query.action) {
2355 		case WLAN_ACTION_SA_QUERY_REQUEST:
2356 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
2357 				break;
2358 			ieee80211_process_sa_query_req(sdata, mgmt, len);
2359 			goto handled;
2360 		}
2361 		break;
2362 	case WLAN_CATEGORY_SELF_PROTECTED:
2363 		switch (mgmt->u.action.u.self_prot.action_code) {
2364 		case WLAN_SP_MESH_PEERING_OPEN:
2365 		case WLAN_SP_MESH_PEERING_CLOSE:
2366 		case WLAN_SP_MESH_PEERING_CONFIRM:
2367 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2368 				goto invalid;
2369 			if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2370 				/* userspace handles this frame */
2371 				break;
2372 			goto queue;
2373 		case WLAN_SP_MGK_INFORM:
2374 		case WLAN_SP_MGK_ACK:
2375 			if (!ieee80211_vif_is_mesh(&sdata->vif))
2376 				goto invalid;
2377 			break;
2378 		}
2379 		break;
2380 	case WLAN_CATEGORY_MESH_ACTION:
2381 		if (!ieee80211_vif_is_mesh(&sdata->vif))
2382 			break;
2383 		if (mesh_action_is_path_sel(mgmt) &&
2384 		  (!mesh_path_sel_is_hwmp(sdata)))
2385 			break;
2386 		goto queue;
2387 	}
2388 
2389 	return RX_CONTINUE;
2390 
2391  invalid:
2392 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2393 	/* will return in the next handlers */
2394 	return RX_CONTINUE;
2395 
2396  handled:
2397 	if (rx->sta)
2398 		rx->sta->rx_packets++;
2399 	dev_kfree_skb(rx->skb);
2400 	return RX_QUEUED;
2401 
2402  queue:
2403 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2404 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2405 	ieee80211_queue_work(&local->hw, &sdata->work);
2406 	if (rx->sta)
2407 		rx->sta->rx_packets++;
2408 	return RX_QUEUED;
2409 }
2410 
2411 static ieee80211_rx_result debug_noinline
2412 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2413 {
2414 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2415 	int sig = 0;
2416 
2417 	/* skip known-bad action frames and return them in the next handler */
2418 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2419 		return RX_CONTINUE;
2420 
2421 	/*
2422 	 * Getting here means the kernel doesn't know how to handle
2423 	 * it, but maybe userspace does ... include returned frames
2424 	 * so userspace can register for those to know whether ones
2425 	 * it transmitted were processed or returned.
2426 	 */
2427 
2428 	if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2429 		sig = status->signal;
2430 
2431 	if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq, sig,
2432 			     rx->skb->data, rx->skb->len,
2433 			     GFP_ATOMIC)) {
2434 		if (rx->sta)
2435 			rx->sta->rx_packets++;
2436 		dev_kfree_skb(rx->skb);
2437 		return RX_QUEUED;
2438 	}
2439 
2440 
2441 	return RX_CONTINUE;
2442 }
2443 
2444 static ieee80211_rx_result debug_noinline
2445 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2446 {
2447 	struct ieee80211_local *local = rx->local;
2448 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2449 	struct sk_buff *nskb;
2450 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2451 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2452 
2453 	if (!ieee80211_is_action(mgmt->frame_control))
2454 		return RX_CONTINUE;
2455 
2456 	/*
2457 	 * For AP mode, hostapd is responsible for handling any action
2458 	 * frames that we didn't handle, including returning unknown
2459 	 * ones. For all other modes we will return them to the sender,
2460 	 * setting the 0x80 bit in the action category, as required by
2461 	 * 802.11-2007 7.3.1.11.
2462 	 * Newer versions of hostapd shall also use the management frame
2463 	 * registration mechanisms, but older ones still use cooked
2464 	 * monitor interfaces so push all frames there.
2465 	 */
2466 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2467 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
2468 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2469 		return RX_DROP_MONITOR;
2470 
2471 	/* do not return rejected action frames */
2472 	if (mgmt->u.action.category & 0x80)
2473 		return RX_DROP_UNUSABLE;
2474 
2475 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2476 			       GFP_ATOMIC);
2477 	if (nskb) {
2478 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2479 
2480 		nmgmt->u.action.category |= 0x80;
2481 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2482 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2483 
2484 		memset(nskb->cb, 0, sizeof(nskb->cb));
2485 
2486 		ieee80211_tx_skb(rx->sdata, nskb);
2487 	}
2488 	dev_kfree_skb(rx->skb);
2489 	return RX_QUEUED;
2490 }
2491 
2492 static ieee80211_rx_result debug_noinline
2493 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2494 {
2495 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2496 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2497 	__le16 stype;
2498 
2499 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2500 
2501 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2502 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2503 	    sdata->vif.type != NL80211_IFTYPE_STATION)
2504 		return RX_DROP_MONITOR;
2505 
2506 	switch (stype) {
2507 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
2508 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
2509 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2510 		/* process for all: mesh, mlme, ibss */
2511 		break;
2512 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2513 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2514 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2515 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2516 		if (is_multicast_ether_addr(mgmt->da) &&
2517 		    !is_broadcast_ether_addr(mgmt->da))
2518 			return RX_DROP_MONITOR;
2519 
2520 		/* process only for station */
2521 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
2522 			return RX_DROP_MONITOR;
2523 		break;
2524 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2525 		/* process only for ibss */
2526 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2527 			return RX_DROP_MONITOR;
2528 		break;
2529 	default:
2530 		return RX_DROP_MONITOR;
2531 	}
2532 
2533 	/* queue up frame and kick off work to process it */
2534 	rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2535 	skb_queue_tail(&sdata->skb_queue, rx->skb);
2536 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
2537 	if (rx->sta)
2538 		rx->sta->rx_packets++;
2539 
2540 	return RX_QUEUED;
2541 }
2542 
2543 /* TODO: use IEEE80211_RX_FRAGMENTED */
2544 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2545 					struct ieee80211_rate *rate)
2546 {
2547 	struct ieee80211_sub_if_data *sdata;
2548 	struct ieee80211_local *local = rx->local;
2549 	struct sk_buff *skb = rx->skb, *skb2;
2550 	struct net_device *prev_dev = NULL;
2551 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2552 	int needed_headroom;
2553 
2554 	/*
2555 	 * If cooked monitor has been processed already, then
2556 	 * don't do it again. If not, set the flag.
2557 	 */
2558 	if (rx->flags & IEEE80211_RX_CMNTR)
2559 		goto out_free_skb;
2560 	rx->flags |= IEEE80211_RX_CMNTR;
2561 
2562 	/* If there are no cooked monitor interfaces, just free the SKB */
2563 	if (!local->cooked_mntrs)
2564 		goto out_free_skb;
2565 
2566 	/* room for the radiotap header based on driver features */
2567 	needed_headroom = ieee80211_rx_radiotap_len(local, status);
2568 
2569 	if (skb_headroom(skb) < needed_headroom &&
2570 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2571 		goto out_free_skb;
2572 
2573 	/* prepend radiotap information */
2574 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
2575 
2576 	skb_set_mac_header(skb, 0);
2577 	skb->ip_summed = CHECKSUM_UNNECESSARY;
2578 	skb->pkt_type = PACKET_OTHERHOST;
2579 	skb->protocol = htons(ETH_P_802_2);
2580 
2581 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2582 		if (!ieee80211_sdata_running(sdata))
2583 			continue;
2584 
2585 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2586 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2587 			continue;
2588 
2589 		if (prev_dev) {
2590 			skb2 = skb_clone(skb, GFP_ATOMIC);
2591 			if (skb2) {
2592 				skb2->dev = prev_dev;
2593 				netif_receive_skb(skb2);
2594 			}
2595 		}
2596 
2597 		prev_dev = sdata->dev;
2598 		sdata->dev->stats.rx_packets++;
2599 		sdata->dev->stats.rx_bytes += skb->len;
2600 	}
2601 
2602 	if (prev_dev) {
2603 		skb->dev = prev_dev;
2604 		netif_receive_skb(skb);
2605 		return;
2606 	}
2607 
2608  out_free_skb:
2609 	dev_kfree_skb(skb);
2610 }
2611 
2612 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2613 					 ieee80211_rx_result res)
2614 {
2615 	switch (res) {
2616 	case RX_DROP_MONITOR:
2617 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2618 		if (rx->sta)
2619 			rx->sta->rx_dropped++;
2620 		/* fall through */
2621 	case RX_CONTINUE: {
2622 		struct ieee80211_rate *rate = NULL;
2623 		struct ieee80211_supported_band *sband;
2624 		struct ieee80211_rx_status *status;
2625 
2626 		status = IEEE80211_SKB_RXCB((rx->skb));
2627 
2628 		sband = rx->local->hw.wiphy->bands[status->band];
2629 		if (!(status->flag & RX_FLAG_HT))
2630 			rate = &sband->bitrates[status->rate_idx];
2631 
2632 		ieee80211_rx_cooked_monitor(rx, rate);
2633 		break;
2634 		}
2635 	case RX_DROP_UNUSABLE:
2636 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2637 		if (rx->sta)
2638 			rx->sta->rx_dropped++;
2639 		dev_kfree_skb(rx->skb);
2640 		break;
2641 	case RX_QUEUED:
2642 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2643 		break;
2644 	}
2645 }
2646 
2647 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2648 {
2649 	ieee80211_rx_result res = RX_DROP_MONITOR;
2650 	struct sk_buff *skb;
2651 
2652 #define CALL_RXH(rxh)			\
2653 	do {				\
2654 		res = rxh(rx);		\
2655 		if (res != RX_CONTINUE)	\
2656 			goto rxh_next;  \
2657 	} while (0);
2658 
2659 	spin_lock(&rx->local->rx_skb_queue.lock);
2660 	if (rx->local->running_rx_handler)
2661 		goto unlock;
2662 
2663 	rx->local->running_rx_handler = true;
2664 
2665 	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2666 		spin_unlock(&rx->local->rx_skb_queue.lock);
2667 
2668 		/*
2669 		 * all the other fields are valid across frames
2670 		 * that belong to an aMPDU since they are on the
2671 		 * same TID from the same station
2672 		 */
2673 		rx->skb = skb;
2674 
2675 		CALL_RXH(ieee80211_rx_h_decrypt)
2676 		CALL_RXH(ieee80211_rx_h_check_more_data)
2677 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2678 		CALL_RXH(ieee80211_rx_h_sta_process)
2679 		CALL_RXH(ieee80211_rx_h_defragment)
2680 		CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2681 		/* must be after MMIC verify so header is counted in MPDU mic */
2682 #ifdef CONFIG_MAC80211_MESH
2683 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2684 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
2685 #endif
2686 		CALL_RXH(ieee80211_rx_h_amsdu)
2687 		CALL_RXH(ieee80211_rx_h_data)
2688 		CALL_RXH(ieee80211_rx_h_ctrl);
2689 		CALL_RXH(ieee80211_rx_h_mgmt_check)
2690 		CALL_RXH(ieee80211_rx_h_action)
2691 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2692 		CALL_RXH(ieee80211_rx_h_action_return)
2693 		CALL_RXH(ieee80211_rx_h_mgmt)
2694 
2695  rxh_next:
2696 		ieee80211_rx_handlers_result(rx, res);
2697 		spin_lock(&rx->local->rx_skb_queue.lock);
2698 #undef CALL_RXH
2699 	}
2700 
2701 	rx->local->running_rx_handler = false;
2702 
2703  unlock:
2704 	spin_unlock(&rx->local->rx_skb_queue.lock);
2705 }
2706 
2707 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2708 {
2709 	ieee80211_rx_result res = RX_DROP_MONITOR;
2710 
2711 #define CALL_RXH(rxh)			\
2712 	do {				\
2713 		res = rxh(rx);		\
2714 		if (res != RX_CONTINUE)	\
2715 			goto rxh_next;  \
2716 	} while (0);
2717 
2718 	CALL_RXH(ieee80211_rx_h_passive_scan)
2719 	CALL_RXH(ieee80211_rx_h_check)
2720 
2721 	ieee80211_rx_reorder_ampdu(rx);
2722 
2723 	ieee80211_rx_handlers(rx);
2724 	return;
2725 
2726  rxh_next:
2727 	ieee80211_rx_handlers_result(rx, res);
2728 
2729 #undef CALL_RXH
2730 }
2731 
2732 /*
2733  * This function makes calls into the RX path, therefore
2734  * it has to be invoked under RCU read lock.
2735  */
2736 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2737 {
2738 	struct ieee80211_rx_data rx = {
2739 		.sta = sta,
2740 		.sdata = sta->sdata,
2741 		.local = sta->local,
2742 		/* This is OK -- must be QoS data frame */
2743 		.security_idx = tid,
2744 		.seqno_idx = tid,
2745 		.flags = 0,
2746 	};
2747 	struct tid_ampdu_rx *tid_agg_rx;
2748 
2749 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2750 	if (!tid_agg_rx)
2751 		return;
2752 
2753 	spin_lock(&tid_agg_rx->reorder_lock);
2754 	ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
2755 	spin_unlock(&tid_agg_rx->reorder_lock);
2756 
2757 	ieee80211_rx_handlers(&rx);
2758 }
2759 
2760 /* main receive path */
2761 
2762 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2763 				struct ieee80211_hdr *hdr)
2764 {
2765 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2766 	struct sk_buff *skb = rx->skb;
2767 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2768 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2769 	int multicast = is_multicast_ether_addr(hdr->addr1);
2770 
2771 	switch (sdata->vif.type) {
2772 	case NL80211_IFTYPE_STATION:
2773 		if (!bssid && !sdata->u.mgd.use_4addr)
2774 			return 0;
2775 		if (!multicast &&
2776 		    compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2777 			if (!(sdata->dev->flags & IFF_PROMISC) ||
2778 			    sdata->u.mgd.use_4addr)
2779 				return 0;
2780 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2781 		}
2782 		break;
2783 	case NL80211_IFTYPE_ADHOC:
2784 		if (!bssid)
2785 			return 0;
2786 		if (ieee80211_is_beacon(hdr->frame_control)) {
2787 			return 1;
2788 		}
2789 		else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2790 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2791 				return 0;
2792 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2793 		} else if (!multicast &&
2794 			   compare_ether_addr(sdata->vif.addr,
2795 					      hdr->addr1) != 0) {
2796 			if (!(sdata->dev->flags & IFF_PROMISC))
2797 				return 0;
2798 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2799 		} else if (!rx->sta) {
2800 			int rate_idx;
2801 			if (status->flag & RX_FLAG_HT)
2802 				rate_idx = 0; /* TODO: HT rates */
2803 			else
2804 				rate_idx = status->rate_idx;
2805 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2806 						 BIT(rate_idx));
2807 		}
2808 		break;
2809 	case NL80211_IFTYPE_MESH_POINT:
2810 		if (!multicast &&
2811 		    compare_ether_addr(sdata->vif.addr,
2812 				       hdr->addr1) != 0) {
2813 			if (!(sdata->dev->flags & IFF_PROMISC))
2814 				return 0;
2815 
2816 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2817 		}
2818 		break;
2819 	case NL80211_IFTYPE_AP_VLAN:
2820 	case NL80211_IFTYPE_AP:
2821 		if (!bssid) {
2822 			if (compare_ether_addr(sdata->vif.addr,
2823 					       hdr->addr1))
2824 				return 0;
2825 		} else if (!ieee80211_bssid_match(bssid,
2826 					sdata->vif.addr)) {
2827 			/*
2828 			 * Accept public action frames even when the
2829 			 * BSSID doesn't match, this is used for P2P
2830 			 * and location updates. Note that mac80211
2831 			 * itself never looks at these frames.
2832 			 */
2833 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2834 			    ieee80211_is_public_action(hdr, skb->len))
2835 				return 1;
2836 			if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2837 			    !ieee80211_is_beacon(hdr->frame_control))
2838 				return 0;
2839 			status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2840 		}
2841 		break;
2842 	case NL80211_IFTYPE_WDS:
2843 		if (bssid || !ieee80211_is_data(hdr->frame_control))
2844 			return 0;
2845 		if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2846 			return 0;
2847 		break;
2848 	default:
2849 		/* should never get here */
2850 		WARN_ON(1);
2851 		break;
2852 	}
2853 
2854 	return 1;
2855 }
2856 
2857 /*
2858  * This function returns whether or not the SKB
2859  * was destined for RX processing or not, which,
2860  * if consume is true, is equivalent to whether
2861  * or not the skb was consumed.
2862  */
2863 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2864 					    struct sk_buff *skb, bool consume)
2865 {
2866 	struct ieee80211_local *local = rx->local;
2867 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2868 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2869 	struct ieee80211_hdr *hdr = (void *)skb->data;
2870 	int prepares;
2871 
2872 	rx->skb = skb;
2873 	status->rx_flags |= IEEE80211_RX_RA_MATCH;
2874 	prepares = prepare_for_handlers(rx, hdr);
2875 
2876 	if (!prepares)
2877 		return false;
2878 
2879 	if (!consume) {
2880 		skb = skb_copy(skb, GFP_ATOMIC);
2881 		if (!skb) {
2882 			if (net_ratelimit())
2883 				wiphy_debug(local->hw.wiphy,
2884 					"failed to copy skb for %s\n",
2885 					sdata->name);
2886 			return true;
2887 		}
2888 
2889 		rx->skb = skb;
2890 	}
2891 
2892 	ieee80211_invoke_rx_handlers(rx);
2893 	return true;
2894 }
2895 
2896 /*
2897  * This is the actual Rx frames handler. as it blongs to Rx path it must
2898  * be called with rcu_read_lock protection.
2899  */
2900 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2901 					 struct sk_buff *skb)
2902 {
2903 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2904 	struct ieee80211_local *local = hw_to_local(hw);
2905 	struct ieee80211_sub_if_data *sdata;
2906 	struct ieee80211_hdr *hdr;
2907 	__le16 fc;
2908 	struct ieee80211_rx_data rx;
2909 	struct ieee80211_sub_if_data *prev;
2910 	struct sta_info *sta, *tmp, *prev_sta;
2911 	int err = 0;
2912 
2913 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2914 	memset(&rx, 0, sizeof(rx));
2915 	rx.skb = skb;
2916 	rx.local = local;
2917 
2918 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2919 		local->dot11ReceivedFragmentCount++;
2920 
2921 	if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2922 		     test_bit(SCAN_SW_SCANNING, &local->scanning)))
2923 		status->rx_flags |= IEEE80211_RX_IN_SCAN;
2924 
2925 	if (ieee80211_is_mgmt(fc))
2926 		err = skb_linearize(skb);
2927 	else
2928 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2929 
2930 	if (err) {
2931 		dev_kfree_skb(skb);
2932 		return;
2933 	}
2934 
2935 	hdr = (struct ieee80211_hdr *)skb->data;
2936 	ieee80211_parse_qos(&rx);
2937 	ieee80211_verify_alignment(&rx);
2938 
2939 	if (ieee80211_is_data(fc)) {
2940 		prev_sta = NULL;
2941 
2942 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
2943 			if (!prev_sta) {
2944 				prev_sta = sta;
2945 				continue;
2946 			}
2947 
2948 			rx.sta = prev_sta;
2949 			rx.sdata = prev_sta->sdata;
2950 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
2951 
2952 			prev_sta = sta;
2953 		}
2954 
2955 		if (prev_sta) {
2956 			rx.sta = prev_sta;
2957 			rx.sdata = prev_sta->sdata;
2958 
2959 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2960 				return;
2961 			goto out;
2962 		}
2963 	}
2964 
2965 	prev = NULL;
2966 
2967 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2968 		if (!ieee80211_sdata_running(sdata))
2969 			continue;
2970 
2971 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2972 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2973 			continue;
2974 
2975 		/*
2976 		 * frame is destined for this interface, but if it's
2977 		 * not also for the previous one we handle that after
2978 		 * the loop to avoid copying the SKB once too much
2979 		 */
2980 
2981 		if (!prev) {
2982 			prev = sdata;
2983 			continue;
2984 		}
2985 
2986 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2987 		rx.sdata = prev;
2988 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
2989 
2990 		prev = sdata;
2991 	}
2992 
2993 	if (prev) {
2994 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
2995 		rx.sdata = prev;
2996 
2997 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2998 			return;
2999 	}
3000 
3001  out:
3002 	dev_kfree_skb(skb);
3003 }
3004 
3005 /*
3006  * This is the receive path handler. It is called by a low level driver when an
3007  * 802.11 MPDU is received from the hardware.
3008  */
3009 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3010 {
3011 	struct ieee80211_local *local = hw_to_local(hw);
3012 	struct ieee80211_rate *rate = NULL;
3013 	struct ieee80211_supported_band *sband;
3014 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3015 
3016 	WARN_ON_ONCE(softirq_count() == 0);
3017 
3018 	if (WARN_ON(status->band < 0 ||
3019 		    status->band >= IEEE80211_NUM_BANDS))
3020 		goto drop;
3021 
3022 	sband = local->hw.wiphy->bands[status->band];
3023 	if (WARN_ON(!sband))
3024 		goto drop;
3025 
3026 	/*
3027 	 * If we're suspending, it is possible although not too likely
3028 	 * that we'd be receiving frames after having already partially
3029 	 * quiesced the stack. We can't process such frames then since
3030 	 * that might, for example, cause stations to be added or other
3031 	 * driver callbacks be invoked.
3032 	 */
3033 	if (unlikely(local->quiescing || local->suspended))
3034 		goto drop;
3035 
3036 	/*
3037 	 * The same happens when we're not even started,
3038 	 * but that's worth a warning.
3039 	 */
3040 	if (WARN_ON(!local->started))
3041 		goto drop;
3042 
3043 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3044 		/*
3045 		 * Validate the rate, unless a PLCP error means that
3046 		 * we probably can't have a valid rate here anyway.
3047 		 */
3048 
3049 		if (status->flag & RX_FLAG_HT) {
3050 			/*
3051 			 * rate_idx is MCS index, which can be [0-76]
3052 			 * as documented on:
3053 			 *
3054 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3055 			 *
3056 			 * Anything else would be some sort of driver or
3057 			 * hardware error. The driver should catch hardware
3058 			 * errors.
3059 			 */
3060 			if (WARN((status->rate_idx < 0 ||
3061 				 status->rate_idx > 76),
3062 				 "Rate marked as an HT rate but passed "
3063 				 "status->rate_idx is not "
3064 				 "an MCS index [0-76]: %d (0x%02x)\n",
3065 				 status->rate_idx,
3066 				 status->rate_idx))
3067 				goto drop;
3068 		} else {
3069 			if (WARN_ON(status->rate_idx < 0 ||
3070 				    status->rate_idx >= sband->n_bitrates))
3071 				goto drop;
3072 			rate = &sband->bitrates[status->rate_idx];
3073 		}
3074 	}
3075 
3076 	status->rx_flags = 0;
3077 
3078 	/*
3079 	 * key references and virtual interfaces are protected using RCU
3080 	 * and this requires that we are in a read-side RCU section during
3081 	 * receive processing
3082 	 */
3083 	rcu_read_lock();
3084 
3085 	/*
3086 	 * Frames with failed FCS/PLCP checksum are not returned,
3087 	 * all other frames are returned without radiotap header
3088 	 * if it was previously present.
3089 	 * Also, frames with less than 16 bytes are dropped.
3090 	 */
3091 	skb = ieee80211_rx_monitor(local, skb, rate);
3092 	if (!skb) {
3093 		rcu_read_unlock();
3094 		return;
3095 	}
3096 
3097 	ieee80211_tpt_led_trig_rx(local,
3098 			((struct ieee80211_hdr *)skb->data)->frame_control,
3099 			skb->len);
3100 	__ieee80211_rx_handle_packet(hw, skb);
3101 
3102 	rcu_read_unlock();
3103 
3104 	return;
3105  drop:
3106 	kfree_skb(skb);
3107 }
3108 EXPORT_SYMBOL(ieee80211_rx);
3109 
3110 /* This is a version of the rx handler that can be called from hard irq
3111  * context. Post the skb on the queue and schedule the tasklet */
3112 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3113 {
3114 	struct ieee80211_local *local = hw_to_local(hw);
3115 
3116 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3117 
3118 	skb->pkt_type = IEEE80211_RX_MSG;
3119 	skb_queue_tail(&local->skb_queue, skb);
3120 	tasklet_schedule(&local->tasklet);
3121 }
3122 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
3123