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mac80211: refactor duplicate detection
[karo-tx-linux.git] / net / mac80211 / rx.c
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  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12
13 #include <linux/jiffies.h>
14 #include <linux/slab.h>
15 #include <linux/kernel.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rcupdate.h>
20 #include <linux/export.h>
21 #include <net/mac80211.h>
22 #include <net/ieee80211_radiotap.h>
23 #include <asm/unaligned.h>
24
25 #include "ieee80211_i.h"
26 #include "driver-ops.h"
27 #include "led.h"
28 #include "mesh.h"
29 #include "wep.h"
30 #include "wpa.h"
31 #include "tkip.h"
32 #include "wme.h"
33 #include "rate.h"
34
35 /*
36  * monitor mode reception
37  *
38  * This function cleans up the SKB, i.e. it removes all the stuff
39  * only useful for monitoring.
40  */
41 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
42                                            struct sk_buff *skb,
43                                            unsigned int rtap_vendor_space)
44 {
45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
46                 if (likely(skb->len > FCS_LEN))
47                         __pskb_trim(skb, skb->len - FCS_LEN);
48                 else {
49                         /* driver bug */
50                         WARN_ON(1);
51                         dev_kfree_skb(skb);
52                         return NULL;
53                 }
54         }
55
56         __pskb_pull(skb, rtap_vendor_space);
57
58         return skb;
59 }
60
61 static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
62                                      unsigned int rtap_vendor_space)
63 {
64         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
65         struct ieee80211_hdr *hdr;
66
67         hdr = (void *)(skb->data + rtap_vendor_space);
68
69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
70                             RX_FLAG_FAILED_PLCP_CRC |
71                             RX_FLAG_AMPDU_IS_ZEROLEN))
72                 return true;
73
74         if (unlikely(skb->len < 16 + present_fcs_len + rtap_vendor_space))
75                 return true;
76
77         if (ieee80211_is_ctl(hdr->frame_control) &&
78             !ieee80211_is_pspoll(hdr->frame_control) &&
79             !ieee80211_is_back_req(hdr->frame_control))
80                 return true;
81
82         return false;
83 }
84
85 static int
86 ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local,
87                              struct ieee80211_rx_status *status,
88                              struct sk_buff *skb)
89 {
90         int len;
91
92         /* always present fields */
93         len = sizeof(struct ieee80211_radiotap_header) + 8;
94
95         /* allocate extra bitmaps */
96         if (status->chains)
97                 len += 4 * hweight8(status->chains);
98
99         if (ieee80211_have_rx_timestamp(status)) {
100                 len = ALIGN(len, 8);
101                 len += 8;
102         }
103         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
104                 len += 1;
105
106         /* antenna field, if we don't have per-chain info */
107         if (!status->chains)
108                 len += 1;
109
110         /* padding for RX_FLAGS if necessary */
111         len = ALIGN(len, 2);
112
113         if (status->flag & RX_FLAG_HT) /* HT info */
114                 len += 3;
115
116         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
117                 len = ALIGN(len, 4);
118                 len += 8;
119         }
120
121         if (status->flag & RX_FLAG_VHT) {
122                 len = ALIGN(len, 2);
123                 len += 12;
124         }
125
126         if (status->chains) {
127                 /* antenna and antenna signal fields */
128                 len += 2 * hweight8(status->chains);
129         }
130
131         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
132                 struct ieee80211_vendor_radiotap *rtap = (void *)skb->data;
133
134                 /* vendor presence bitmap */
135                 len += 4;
136                 /* alignment for fixed 6-byte vendor data header */
137                 len = ALIGN(len, 2);
138                 /* vendor data header */
139                 len += 6;
140                 if (WARN_ON(rtap->align == 0))
141                         rtap->align = 1;
142                 len = ALIGN(len, rtap->align);
143                 len += rtap->len + rtap->pad;
144         }
145
146         return len;
147 }
148
149 /*
150  * ieee80211_add_rx_radiotap_header - add radiotap header
151  *
152  * add a radiotap header containing all the fields which the hardware provided.
153  */
154 static void
155 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
156                                  struct sk_buff *skb,
157                                  struct ieee80211_rate *rate,
158                                  int rtap_len, bool has_fcs)
159 {
160         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
161         struct ieee80211_radiotap_header *rthdr;
162         unsigned char *pos;
163         __le32 *it_present;
164         u32 it_present_val;
165         u16 rx_flags = 0;
166         u16 channel_flags = 0;
167         int mpdulen, chain;
168         unsigned long chains = status->chains;
169         struct ieee80211_vendor_radiotap rtap = {};
170
171         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
172                 rtap = *(struct ieee80211_vendor_radiotap *)skb->data;
173                 /* rtap.len and rtap.pad are undone immediately */
174                 skb_pull(skb, sizeof(rtap) + rtap.len + rtap.pad);
175         }
176
177         mpdulen = skb->len;
178         if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)))
179                 mpdulen += FCS_LEN;
180
181         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
182         memset(rthdr, 0, rtap_len - rtap.len - rtap.pad);
183         it_present = &rthdr->it_present;
184
185         /* radiotap header, set always present flags */
186         rthdr->it_len = cpu_to_le16(rtap_len);
187         it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) |
188                          BIT(IEEE80211_RADIOTAP_CHANNEL) |
189                          BIT(IEEE80211_RADIOTAP_RX_FLAGS);
190
191         if (!status->chains)
192                 it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA);
193
194         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
195                 it_present_val |=
196                         BIT(IEEE80211_RADIOTAP_EXT) |
197                         BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE);
198                 put_unaligned_le32(it_present_val, it_present);
199                 it_present++;
200                 it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) |
201                                  BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
202         }
203
204         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
205                 it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
206                                   BIT(IEEE80211_RADIOTAP_EXT);
207                 put_unaligned_le32(it_present_val, it_present);
208                 it_present++;
209                 it_present_val = rtap.present;
210         }
211
212         put_unaligned_le32(it_present_val, it_present);
213
214         pos = (void *)(it_present + 1);
215
216         /* the order of the following fields is important */
217
218         /* IEEE80211_RADIOTAP_TSFT */
219         if (ieee80211_have_rx_timestamp(status)) {
220                 /* padding */
221                 while ((pos - (u8 *)rthdr) & 7)
222                         *pos++ = 0;
223                 put_unaligned_le64(
224                         ieee80211_calculate_rx_timestamp(local, status,
225                                                          mpdulen, 0),
226                         pos);
227                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
228                 pos += 8;
229         }
230
231         /* IEEE80211_RADIOTAP_FLAGS */
232         if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
233                 *pos |= IEEE80211_RADIOTAP_F_FCS;
234         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
235                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
236         if (status->flag & RX_FLAG_SHORTPRE)
237                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
238         pos++;
239
240         /* IEEE80211_RADIOTAP_RATE */
241         if (!rate || status->flag & (RX_FLAG_HT | RX_FLAG_VHT)) {
242                 /*
243                  * Without rate information don't add it. If we have,
244                  * MCS information is a separate field in radiotap,
245                  * added below. The byte here is needed as padding
246                  * for the channel though, so initialise it to 0.
247                  */
248                 *pos = 0;
249         } else {
250                 int shift = 0;
251                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
252                 if (status->flag & RX_FLAG_10MHZ)
253                         shift = 1;
254                 else if (status->flag & RX_FLAG_5MHZ)
255                         shift = 2;
256                 *pos = DIV_ROUND_UP(rate->bitrate, 5 * (1 << shift));
257         }
258         pos++;
259
260         /* IEEE80211_RADIOTAP_CHANNEL */
261         put_unaligned_le16(status->freq, pos);
262         pos += 2;
263         if (status->flag & RX_FLAG_10MHZ)
264                 channel_flags |= IEEE80211_CHAN_HALF;
265         else if (status->flag & RX_FLAG_5MHZ)
266                 channel_flags |= IEEE80211_CHAN_QUARTER;
267
268         if (status->band == IEEE80211_BAND_5GHZ)
269                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ;
270         else if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
271                 channel_flags |= IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
272         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
273                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
274         else if (rate)
275                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
276         else
277                 channel_flags |= IEEE80211_CHAN_2GHZ;
278         put_unaligned_le16(channel_flags, pos);
279         pos += 2;
280
281         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
282         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
283             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
284                 *pos = status->signal;
285                 rthdr->it_present |=
286                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
287                 pos++;
288         }
289
290         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
291
292         if (!status->chains) {
293                 /* IEEE80211_RADIOTAP_ANTENNA */
294                 *pos = status->antenna;
295                 pos++;
296         }
297
298         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
299
300         /* IEEE80211_RADIOTAP_RX_FLAGS */
301         /* ensure 2 byte alignment for the 2 byte field as required */
302         if ((pos - (u8 *)rthdr) & 1)
303                 *pos++ = 0;
304         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
305                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
306         put_unaligned_le16(rx_flags, pos);
307         pos += 2;
308
309         if (status->flag & RX_FLAG_HT) {
310                 unsigned int stbc;
311
312                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
313                 *pos++ = local->hw.radiotap_mcs_details;
314                 *pos = 0;
315                 if (status->flag & RX_FLAG_SHORT_GI)
316                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
317                 if (status->flag & RX_FLAG_40MHZ)
318                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
319                 if (status->flag & RX_FLAG_HT_GF)
320                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
321                 if (status->flag & RX_FLAG_LDPC)
322                         *pos |= IEEE80211_RADIOTAP_MCS_FEC_LDPC;
323                 stbc = (status->flag & RX_FLAG_STBC_MASK) >> RX_FLAG_STBC_SHIFT;
324                 *pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
325                 pos++;
326                 *pos++ = status->rate_idx;
327         }
328
329         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
330                 u16 flags = 0;
331
332                 /* ensure 4 byte alignment */
333                 while ((pos - (u8 *)rthdr) & 3)
334                         pos++;
335                 rthdr->it_present |=
336                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
337                 put_unaligned_le32(status->ampdu_reference, pos);
338                 pos += 4;
339                 if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
340                         flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
341                 if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
342                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
343                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
344                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
345                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
346                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
347                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
348                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
349                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
350                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
351                 put_unaligned_le16(flags, pos);
352                 pos += 2;
353                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
354                         *pos++ = status->ampdu_delimiter_crc;
355                 else
356                         *pos++ = 0;
357                 *pos++ = 0;
358         }
359
360         if (status->flag & RX_FLAG_VHT) {
361                 u16 known = local->hw.radiotap_vht_details;
362
363                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
364                 /* known field - how to handle 80+80? */
365                 if (status->vht_flag & RX_VHT_FLAG_80P80MHZ)
366                         known &= ~IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
367                 put_unaligned_le16(known, pos);
368                 pos += 2;
369                 /* flags */
370                 if (status->flag & RX_FLAG_SHORT_GI)
371                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
372                 /* in VHT, STBC is binary */
373                 if (status->flag & RX_FLAG_STBC_MASK)
374                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_STBC;
375                 if (status->vht_flag & RX_VHT_FLAG_BF)
376                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_BEAMFORMED;
377                 pos++;
378                 /* bandwidth */
379                 if (status->vht_flag & RX_VHT_FLAG_80MHZ)
380                         *pos++ = 4;
381                 else if (status->vht_flag & RX_VHT_FLAG_80P80MHZ)
382                         *pos++ = 0; /* marked not known above */
383                 else if (status->vht_flag & RX_VHT_FLAG_160MHZ)
384                         *pos++ = 11;
385                 else if (status->flag & RX_FLAG_40MHZ)
386                         *pos++ = 1;
387                 else /* 20 MHz */
388                         *pos++ = 0;
389                 /* MCS/NSS */
390                 *pos = (status->rate_idx << 4) | status->vht_nss;
391                 pos += 4;
392                 /* coding field */
393                 if (status->flag & RX_FLAG_LDPC)
394                         *pos |= IEEE80211_RADIOTAP_CODING_LDPC_USER0;
395                 pos++;
396                 /* group ID */
397                 pos++;
398                 /* partial_aid */
399                 pos += 2;
400         }
401
402         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
403                 *pos++ = status->chain_signal[chain];
404                 *pos++ = chain;
405         }
406
407         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
408                 /* ensure 2 byte alignment for the vendor field as required */
409                 if ((pos - (u8 *)rthdr) & 1)
410                         *pos++ = 0;
411                 *pos++ = rtap.oui[0];
412                 *pos++ = rtap.oui[1];
413                 *pos++ = rtap.oui[2];
414                 *pos++ = rtap.subns;
415                 put_unaligned_le16(rtap.len, pos);
416                 pos += 2;
417                 /* align the actual payload as requested */
418                 while ((pos - (u8 *)rthdr) & (rtap.align - 1))
419                         *pos++ = 0;
420                 /* data (and possible padding) already follows */
421         }
422 }
423
424 /*
425  * This function copies a received frame to all monitor interfaces and
426  * returns a cleaned-up SKB that no longer includes the FCS nor the
427  * radiotap header the driver might have added.
428  */
429 static struct sk_buff *
430 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
431                      struct ieee80211_rate *rate)
432 {
433         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
434         struct ieee80211_sub_if_data *sdata;
435         int rt_hdrlen, needed_headroom;
436         struct sk_buff *skb, *skb2;
437         struct net_device *prev_dev = NULL;
438         int present_fcs_len = 0;
439         unsigned int rtap_vendor_space = 0;
440
441         if (unlikely(status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)) {
442                 struct ieee80211_vendor_radiotap *rtap = (void *)origskb->data;
443
444                 rtap_vendor_space = sizeof(*rtap) + rtap->len + rtap->pad;
445         }
446
447         /*
448          * First, we may need to make a copy of the skb because
449          *  (1) we need to modify it for radiotap (if not present), and
450          *  (2) the other RX handlers will modify the skb we got.
451          *
452          * We don't need to, of course, if we aren't going to return
453          * the SKB because it has a bad FCS/PLCP checksum.
454          */
455
456         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
457                 present_fcs_len = FCS_LEN;
458
459         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
460         if (!pskb_may_pull(origskb, 2 + rtap_vendor_space)) {
461                 dev_kfree_skb(origskb);
462                 return NULL;
463         }
464
465         if (!local->monitors) {
466                 if (should_drop_frame(origskb, present_fcs_len,
467                                       rtap_vendor_space)) {
468                         dev_kfree_skb(origskb);
469                         return NULL;
470                 }
471
472                 return remove_monitor_info(local, origskb, rtap_vendor_space);
473         }
474
475         /* room for the radiotap header based on driver features */
476         rt_hdrlen = ieee80211_rx_radiotap_hdrlen(local, status, origskb);
477         needed_headroom = rt_hdrlen - rtap_vendor_space;
478
479         if (should_drop_frame(origskb, present_fcs_len, rtap_vendor_space)) {
480                 /* only need to expand headroom if necessary */
481                 skb = origskb;
482                 origskb = NULL;
483
484                 /*
485                  * This shouldn't trigger often because most devices have an
486                  * RX header they pull before we get here, and that should
487                  * be big enough for our radiotap information. We should
488                  * probably export the length to drivers so that we can have
489                  * them allocate enough headroom to start with.
490                  */
491                 if (skb_headroom(skb) < needed_headroom &&
492                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
493                         dev_kfree_skb(skb);
494                         return NULL;
495                 }
496         } else {
497                 /*
498                  * Need to make a copy and possibly remove radiotap header
499                  * and FCS from the original.
500                  */
501                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
502
503                 origskb = remove_monitor_info(local, origskb,
504                                               rtap_vendor_space);
505
506                 if (!skb)
507                         return origskb;
508         }
509
510         /* prepend radiotap information */
511         ieee80211_add_rx_radiotap_header(local, skb, rate, rt_hdrlen, true);
512
513         skb_reset_mac_header(skb);
514         skb->ip_summed = CHECKSUM_UNNECESSARY;
515         skb->pkt_type = PACKET_OTHERHOST;
516         skb->protocol = htons(ETH_P_802_2);
517
518         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
519                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
520                         continue;
521
522                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
523                         continue;
524
525                 if (!ieee80211_sdata_running(sdata))
526                         continue;
527
528                 if (prev_dev) {
529                         skb2 = skb_clone(skb, GFP_ATOMIC);
530                         if (skb2) {
531                                 skb2->dev = prev_dev;
532                                 netif_receive_skb(skb2);
533                         }
534                 }
535
536                 prev_dev = sdata->dev;
537                 sdata->dev->stats.rx_packets++;
538                 sdata->dev->stats.rx_bytes += skb->len;
539         }
540
541         if (prev_dev) {
542                 skb->dev = prev_dev;
543                 netif_receive_skb(skb);
544         } else
545                 dev_kfree_skb(skb);
546
547         return origskb;
548 }
549
550 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
551 {
552         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
553         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
554         int tid, seqno_idx, security_idx;
555
556         /* does the frame have a qos control field? */
557         if (ieee80211_is_data_qos(hdr->frame_control)) {
558                 u8 *qc = ieee80211_get_qos_ctl(hdr);
559                 /* frame has qos control */
560                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
561                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
562                         status->rx_flags |= IEEE80211_RX_AMSDU;
563
564                 seqno_idx = tid;
565                 security_idx = tid;
566         } else {
567                 /*
568                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
569                  *
570                  *      Sequence numbers for management frames, QoS data
571                  *      frames with a broadcast/multicast address in the
572                  *      Address 1 field, and all non-QoS data frames sent
573                  *      by QoS STAs are assigned using an additional single
574                  *      modulo-4096 counter, [...]
575                  *
576                  * We also use that counter for non-QoS STAs.
577                  */
578                 seqno_idx = IEEE80211_NUM_TIDS;
579                 security_idx = 0;
580                 if (ieee80211_is_mgmt(hdr->frame_control))
581                         security_idx = IEEE80211_NUM_TIDS;
582                 tid = 0;
583         }
584
585         rx->seqno_idx = seqno_idx;
586         rx->security_idx = security_idx;
587         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
588          * For now, set skb->priority to 0 for other cases. */
589         rx->skb->priority = (tid > 7) ? 0 : tid;
590 }
591
592 /**
593  * DOC: Packet alignment
594  *
595  * Drivers always need to pass packets that are aligned to two-byte boundaries
596  * to the stack.
597  *
598  * Additionally, should, if possible, align the payload data in a way that
599  * guarantees that the contained IP header is aligned to a four-byte
600  * boundary. In the case of regular frames, this simply means aligning the
601  * payload to a four-byte boundary (because either the IP header is directly
602  * contained, or IV/RFC1042 headers that have a length divisible by four are
603  * in front of it).  If the payload data is not properly aligned and the
604  * architecture doesn't support efficient unaligned operations, mac80211
605  * will align the data.
606  *
607  * With A-MSDU frames, however, the payload data address must yield two modulo
608  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
609  * push the IP header further back to a multiple of four again. Thankfully, the
610  * specs were sane enough this time around to require padding each A-MSDU
611  * subframe to a length that is a multiple of four.
612  *
613  * Padding like Atheros hardware adds which is between the 802.11 header and
614  * the payload is not supported, the driver is required to move the 802.11
615  * header to be directly in front of the payload in that case.
616  */
617 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
618 {
619 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
620         WARN_ONCE((unsigned long)rx->skb->data & 1,
621                   "unaligned packet at 0x%p\n", rx->skb->data);
622 #endif
623 }
624
625
626 /* rx handlers */
627
628 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
629 {
630         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
631
632         if (is_multicast_ether_addr(hdr->addr1))
633                 return 0;
634
635         return ieee80211_is_robust_mgmt_frame(skb);
636 }
637
638
639 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
640 {
641         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
642
643         if (!is_multicast_ether_addr(hdr->addr1))
644                 return 0;
645
646         return ieee80211_is_robust_mgmt_frame(skb);
647 }
648
649
650 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
651 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
652 {
653         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
654         struct ieee80211_mmie *mmie;
655
656         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
657                 return -1;
658
659         if (!ieee80211_is_robust_mgmt_frame(skb))
660                 return -1; /* not a robust management frame */
661
662         mmie = (struct ieee80211_mmie *)
663                 (skb->data + skb->len - sizeof(*mmie));
664         if (mmie->element_id != WLAN_EID_MMIE ||
665             mmie->length != sizeof(*mmie) - 2)
666                 return -1;
667
668         return le16_to_cpu(mmie->key_id);
669 }
670
671 static int iwl80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs,
672                                  struct sk_buff *skb)
673 {
674         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
675         __le16 fc;
676         int hdrlen;
677         u8 keyid;
678
679         fc = hdr->frame_control;
680         hdrlen = ieee80211_hdrlen(fc);
681
682         if (skb->len < hdrlen + cs->hdr_len)
683                 return -EINVAL;
684
685         skb_copy_bits(skb, hdrlen + cs->key_idx_off, &keyid, 1);
686         keyid &= cs->key_idx_mask;
687         keyid >>= cs->key_idx_shift;
688
689         return keyid;
690 }
691
692 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
693 {
694         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
695         char *dev_addr = rx->sdata->vif.addr;
696
697         if (ieee80211_is_data(hdr->frame_control)) {
698                 if (is_multicast_ether_addr(hdr->addr1)) {
699                         if (ieee80211_has_tods(hdr->frame_control) ||
700                             !ieee80211_has_fromds(hdr->frame_control))
701                                 return RX_DROP_MONITOR;
702                         if (ether_addr_equal(hdr->addr3, dev_addr))
703                                 return RX_DROP_MONITOR;
704                 } else {
705                         if (!ieee80211_has_a4(hdr->frame_control))
706                                 return RX_DROP_MONITOR;
707                         if (ether_addr_equal(hdr->addr4, dev_addr))
708                                 return RX_DROP_MONITOR;
709                 }
710         }
711
712         /* If there is not an established peer link and this is not a peer link
713          * establisment frame, beacon or probe, drop the frame.
714          */
715
716         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
717                 struct ieee80211_mgmt *mgmt;
718
719                 if (!ieee80211_is_mgmt(hdr->frame_control))
720                         return RX_DROP_MONITOR;
721
722                 if (ieee80211_is_action(hdr->frame_control)) {
723                         u8 category;
724
725                         /* make sure category field is present */
726                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
727                                 return RX_DROP_MONITOR;
728
729                         mgmt = (struct ieee80211_mgmt *)hdr;
730                         category = mgmt->u.action.category;
731                         if (category != WLAN_CATEGORY_MESH_ACTION &&
732                             category != WLAN_CATEGORY_SELF_PROTECTED)
733                                 return RX_DROP_MONITOR;
734                         return RX_CONTINUE;
735                 }
736
737                 if (ieee80211_is_probe_req(hdr->frame_control) ||
738                     ieee80211_is_probe_resp(hdr->frame_control) ||
739                     ieee80211_is_beacon(hdr->frame_control) ||
740                     ieee80211_is_auth(hdr->frame_control))
741                         return RX_CONTINUE;
742
743                 return RX_DROP_MONITOR;
744         }
745
746         return RX_CONTINUE;
747 }
748
749 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
750                                             struct tid_ampdu_rx *tid_agg_rx,
751                                             int index,
752                                             struct sk_buff_head *frames)
753 {
754         struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index];
755         struct sk_buff *skb;
756         struct ieee80211_rx_status *status;
757
758         lockdep_assert_held(&tid_agg_rx->reorder_lock);
759
760         if (skb_queue_empty(skb_list))
761                 goto no_frame;
762
763         if (!ieee80211_rx_reorder_ready(skb_list)) {
764                 __skb_queue_purge(skb_list);
765                 goto no_frame;
766         }
767
768         /* release frames from the reorder ring buffer */
769         tid_agg_rx->stored_mpdu_num--;
770         while ((skb = __skb_dequeue(skb_list))) {
771                 status = IEEE80211_SKB_RXCB(skb);
772                 status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
773                 __skb_queue_tail(frames, skb);
774         }
775
776 no_frame:
777         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
778 }
779
780 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
781                                              struct tid_ampdu_rx *tid_agg_rx,
782                                              u16 head_seq_num,
783                                              struct sk_buff_head *frames)
784 {
785         int index;
786
787         lockdep_assert_held(&tid_agg_rx->reorder_lock);
788
789         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
790                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
791                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
792                                                 frames);
793         }
794 }
795
796 /*
797  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
798  * the skb was added to the buffer longer than this time ago, the earlier
799  * frames that have not yet been received are assumed to be lost and the skb
800  * can be released for processing. This may also release other skb's from the
801  * reorder buffer if there are no additional gaps between the frames.
802  *
803  * Callers must hold tid_agg_rx->reorder_lock.
804  */
805 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
806
807 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
808                                           struct tid_ampdu_rx *tid_agg_rx,
809                                           struct sk_buff_head *frames)
810 {
811         int index, i, j;
812
813         lockdep_assert_held(&tid_agg_rx->reorder_lock);
814
815         /* release the buffer until next missing frame */
816         index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
817         if (!ieee80211_rx_reorder_ready(&tid_agg_rx->reorder_buf[index]) &&
818             tid_agg_rx->stored_mpdu_num) {
819                 /*
820                  * No buffers ready to be released, but check whether any
821                  * frames in the reorder buffer have timed out.
822                  */
823                 int skipped = 1;
824                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
825                      j = (j + 1) % tid_agg_rx->buf_size) {
826                         if (!ieee80211_rx_reorder_ready(
827                                         &tid_agg_rx->reorder_buf[j])) {
828                                 skipped++;
829                                 continue;
830                         }
831                         if (skipped &&
832                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
833                                         HT_RX_REORDER_BUF_TIMEOUT))
834                                 goto set_release_timer;
835
836                         /* don't leave incomplete A-MSDUs around */
837                         for (i = (index + 1) % tid_agg_rx->buf_size; i != j;
838                              i = (i + 1) % tid_agg_rx->buf_size)
839                                 __skb_queue_purge(&tid_agg_rx->reorder_buf[i]);
840
841                         ht_dbg_ratelimited(sdata,
842                                            "release an RX reorder frame due to timeout on earlier frames\n");
843                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
844                                                         frames);
845
846                         /*
847                          * Increment the head seq# also for the skipped slots.
848                          */
849                         tid_agg_rx->head_seq_num =
850                                 (tid_agg_rx->head_seq_num +
851                                  skipped) & IEEE80211_SN_MASK;
852                         skipped = 0;
853                 }
854         } else while (ieee80211_rx_reorder_ready(
855                                 &tid_agg_rx->reorder_buf[index])) {
856                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
857                                                 frames);
858                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
859         }
860
861         if (tid_agg_rx->stored_mpdu_num) {
862                 j = index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
863
864                 for (; j != (index - 1) % tid_agg_rx->buf_size;
865                      j = (j + 1) % tid_agg_rx->buf_size) {
866                         if (ieee80211_rx_reorder_ready(
867                                         &tid_agg_rx->reorder_buf[j]))
868                                 break;
869                 }
870
871  set_release_timer:
872
873                 mod_timer(&tid_agg_rx->reorder_timer,
874                           tid_agg_rx->reorder_time[j] + 1 +
875                           HT_RX_REORDER_BUF_TIMEOUT);
876         } else {
877                 del_timer(&tid_agg_rx->reorder_timer);
878         }
879 }
880
881 /*
882  * As this function belongs to the RX path it must be under
883  * rcu_read_lock protection. It returns false if the frame
884  * can be processed immediately, true if it was consumed.
885  */
886 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
887                                              struct tid_ampdu_rx *tid_agg_rx,
888                                              struct sk_buff *skb,
889                                              struct sk_buff_head *frames)
890 {
891         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
892         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
893         u16 sc = le16_to_cpu(hdr->seq_ctrl);
894         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
895         u16 head_seq_num, buf_size;
896         int index;
897         bool ret = true;
898
899         spin_lock(&tid_agg_rx->reorder_lock);
900
901         /*
902          * Offloaded BA sessions have no known starting sequence number so pick
903          * one from first Rxed frame for this tid after BA was started.
904          */
905         if (unlikely(tid_agg_rx->auto_seq)) {
906                 tid_agg_rx->auto_seq = false;
907                 tid_agg_rx->ssn = mpdu_seq_num;
908                 tid_agg_rx->head_seq_num = mpdu_seq_num;
909         }
910
911         buf_size = tid_agg_rx->buf_size;
912         head_seq_num = tid_agg_rx->head_seq_num;
913
914         /* frame with out of date sequence number */
915         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
916                 dev_kfree_skb(skb);
917                 goto out;
918         }
919
920         /*
921          * If frame the sequence number exceeds our buffering window
922          * size release some previous frames to make room for this one.
923          */
924         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
925                 head_seq_num = ieee80211_sn_inc(
926                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
927                 /* release stored frames up to new head to stack */
928                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
929                                                  head_seq_num, frames);
930         }
931
932         /* Now the new frame is always in the range of the reordering buffer */
933
934         index = mpdu_seq_num % tid_agg_rx->buf_size;
935
936         /* check if we already stored this frame */
937         if (ieee80211_rx_reorder_ready(&tid_agg_rx->reorder_buf[index])) {
938                 dev_kfree_skb(skb);
939                 goto out;
940         }
941
942         /*
943          * If the current MPDU is in the right order and nothing else
944          * is stored we can process it directly, no need to buffer it.
945          * If it is first but there's something stored, we may be able
946          * to release frames after this one.
947          */
948         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
949             tid_agg_rx->stored_mpdu_num == 0) {
950                 if (!(status->flag & RX_FLAG_AMSDU_MORE))
951                         tid_agg_rx->head_seq_num =
952                                 ieee80211_sn_inc(tid_agg_rx->head_seq_num);
953                 ret = false;
954                 goto out;
955         }
956
957         /* put the frame in the reordering buffer */
958         __skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb);
959         if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
960                 tid_agg_rx->reorder_time[index] = jiffies;
961                 tid_agg_rx->stored_mpdu_num++;
962                 ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
963         }
964
965  out:
966         spin_unlock(&tid_agg_rx->reorder_lock);
967         return ret;
968 }
969
970 /*
971  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
972  * true if the MPDU was buffered, false if it should be processed.
973  */
974 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
975                                        struct sk_buff_head *frames)
976 {
977         struct sk_buff *skb = rx->skb;
978         struct ieee80211_local *local = rx->local;
979         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
980         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
981         struct sta_info *sta = rx->sta;
982         struct tid_ampdu_rx *tid_agg_rx;
983         u16 sc;
984         u8 tid, ack_policy;
985
986         if (!ieee80211_is_data_qos(hdr->frame_control) ||
987             is_multicast_ether_addr(hdr->addr1))
988                 goto dont_reorder;
989
990         /*
991          * filter the QoS data rx stream according to
992          * STA/TID and check if this STA/TID is on aggregation
993          */
994
995         if (!sta)
996                 goto dont_reorder;
997
998         ack_policy = *ieee80211_get_qos_ctl(hdr) &
999                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
1000         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1001
1002         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
1003         if (!tid_agg_rx)
1004                 goto dont_reorder;
1005
1006         /* qos null data frames are excluded */
1007         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
1008                 goto dont_reorder;
1009
1010         /* not part of a BA session */
1011         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1012             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
1013                 goto dont_reorder;
1014
1015         /* not actually part of this BA session */
1016         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1017                 goto dont_reorder;
1018
1019         /* new, potentially un-ordered, ampdu frame - process it */
1020
1021         /* reset session timer */
1022         if (tid_agg_rx->timeout)
1023                 tid_agg_rx->last_rx = jiffies;
1024
1025         /* if this mpdu is fragmented - terminate rx aggregation session */
1026         sc = le16_to_cpu(hdr->seq_ctrl);
1027         if (sc & IEEE80211_SCTL_FRAG) {
1028                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
1029                 skb_queue_tail(&rx->sdata->skb_queue, skb);
1030                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
1031                 return;
1032         }
1033
1034         /*
1035          * No locking needed -- we will only ever process one
1036          * RX packet at a time, and thus own tid_agg_rx. All
1037          * other code manipulating it needs to (and does) make
1038          * sure that we cannot get to it any more before doing
1039          * anything with it.
1040          */
1041         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
1042                                              frames))
1043                 return;
1044
1045  dont_reorder:
1046         __skb_queue_tail(frames, skb);
1047 }
1048
1049 static ieee80211_rx_result debug_noinline
1050 ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
1051 {
1052         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1053         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1054
1055         /*
1056          * Drop duplicate 802.11 retransmissions
1057          * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
1058          */
1059
1060         if (rx->skb->len < 24)
1061                 return RX_CONTINUE;
1062
1063         if (ieee80211_is_ctl(hdr->frame_control) ||
1064             ieee80211_is_qos_nullfunc(hdr->frame_control) ||
1065             is_multicast_ether_addr(hdr->addr1))
1066                 return RX_CONTINUE;
1067
1068         if (rx->sta) {
1069                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
1070                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
1071                              hdr->seq_ctrl)) {
1072                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1073                                 rx->local->dot11FrameDuplicateCount++;
1074                                 rx->sta->num_duplicates++;
1075                         }
1076                         return RX_DROP_UNUSABLE;
1077                 } else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1078                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
1079                 }
1080         }
1081
1082         return RX_CONTINUE;
1083 }
1084
1085 static ieee80211_rx_result debug_noinline
1086 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
1087 {
1088         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1089
1090         if (unlikely(rx->skb->len < 16)) {
1091                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
1092                 return RX_DROP_MONITOR;
1093         }
1094
1095         /* Drop disallowed frame classes based on STA auth/assoc state;
1096          * IEEE 802.11, Chap 5.5.
1097          *
1098          * mac80211 filters only based on association state, i.e. it drops
1099          * Class 3 frames from not associated stations. hostapd sends
1100          * deauth/disassoc frames when needed. In addition, hostapd is
1101          * responsible for filtering on both auth and assoc states.
1102          */
1103
1104         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1105                 return ieee80211_rx_mesh_check(rx);
1106
1107         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
1108                       ieee80211_is_pspoll(hdr->frame_control)) &&
1109                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
1110                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
1111                      rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
1112                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
1113                 /*
1114                  * accept port control frames from the AP even when it's not
1115                  * yet marked ASSOC to prevent a race where we don't set the
1116                  * assoc bit quickly enough before it sends the first frame
1117                  */
1118                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1119                     ieee80211_is_data_present(hdr->frame_control)) {
1120                         unsigned int hdrlen;
1121                         __be16 ethertype;
1122
1123                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1124
1125                         if (rx->skb->len < hdrlen + 8)
1126                                 return RX_DROP_MONITOR;
1127
1128                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
1129                         if (ethertype == rx->sdata->control_port_protocol)
1130                                 return RX_CONTINUE;
1131                 }
1132
1133                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1134                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1135                                                hdr->addr2,
1136                                                GFP_ATOMIC))
1137                         return RX_DROP_UNUSABLE;
1138
1139                 return RX_DROP_MONITOR;
1140         }
1141
1142         return RX_CONTINUE;
1143 }
1144
1145
1146 static ieee80211_rx_result debug_noinline
1147 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1148 {
1149         struct ieee80211_local *local;
1150         struct ieee80211_hdr *hdr;
1151         struct sk_buff *skb;
1152
1153         local = rx->local;
1154         skb = rx->skb;
1155         hdr = (struct ieee80211_hdr *) skb->data;
1156
1157         if (!local->pspolling)
1158                 return RX_CONTINUE;
1159
1160         if (!ieee80211_has_fromds(hdr->frame_control))
1161                 /* this is not from AP */
1162                 return RX_CONTINUE;
1163
1164         if (!ieee80211_is_data(hdr->frame_control))
1165                 return RX_CONTINUE;
1166
1167         if (!ieee80211_has_moredata(hdr->frame_control)) {
1168                 /* AP has no more frames buffered for us */
1169                 local->pspolling = false;
1170                 return RX_CONTINUE;
1171         }
1172
1173         /* more data bit is set, let's request a new frame from the AP */
1174         ieee80211_send_pspoll(local, rx->sdata);
1175
1176         return RX_CONTINUE;
1177 }
1178
1179 static void sta_ps_start(struct sta_info *sta)
1180 {
1181         struct ieee80211_sub_if_data *sdata = sta->sdata;
1182         struct ieee80211_local *local = sdata->local;
1183         struct ps_data *ps;
1184
1185         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1186             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1187                 ps = &sdata->bss->ps;
1188         else
1189                 return;
1190
1191         atomic_inc(&ps->num_sta_ps);
1192         set_sta_flag(sta, WLAN_STA_PS_STA);
1193         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1194                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1195         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1196                sta->sta.addr, sta->sta.aid);
1197 }
1198
1199 static void sta_ps_end(struct sta_info *sta)
1200 {
1201         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1202                sta->sta.addr, sta->sta.aid);
1203
1204         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1205                 /*
1206                  * Clear the flag only if the other one is still set
1207                  * so that the TX path won't start TX'ing new frames
1208                  * directly ... In the case that the driver flag isn't
1209                  * set ieee80211_sta_ps_deliver_wakeup() will clear it.
1210                  */
1211                 clear_sta_flag(sta, WLAN_STA_PS_STA);
1212                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1213                        sta->sta.addr, sta->sta.aid);
1214                 return;
1215         }
1216
1217         set_sta_flag(sta, WLAN_STA_PS_DELIVER);
1218         clear_sta_flag(sta, WLAN_STA_PS_STA);
1219         ieee80211_sta_ps_deliver_wakeup(sta);
1220 }
1221
1222 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1223 {
1224         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1225         bool in_ps;
1226
1227         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1228
1229         /* Don't let the same PS state be set twice */
1230         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1231         if ((start && in_ps) || (!start && !in_ps))
1232                 return -EINVAL;
1233
1234         if (start)
1235                 sta_ps_start(sta_inf);
1236         else
1237                 sta_ps_end(sta_inf);
1238
1239         return 0;
1240 }
1241 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1242
1243 static ieee80211_rx_result debug_noinline
1244 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1245 {
1246         struct ieee80211_sub_if_data *sdata = rx->sdata;
1247         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1248         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1249         int tid, ac;
1250
1251         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1252                 return RX_CONTINUE;
1253
1254         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1255             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1256                 return RX_CONTINUE;
1257
1258         /*
1259          * The device handles station powersave, so don't do anything about
1260          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1261          * it to mac80211 since they're handled.)
1262          */
1263         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1264                 return RX_CONTINUE;
1265
1266         /*
1267          * Don't do anything if the station isn't already asleep. In
1268          * the uAPSD case, the station will probably be marked asleep,
1269          * in the PS-Poll case the station must be confused ...
1270          */
1271         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1272                 return RX_CONTINUE;
1273
1274         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1275                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1276                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1277                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1278                         else
1279                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1280                 }
1281
1282                 /* Free PS Poll skb here instead of returning RX_DROP that would
1283                  * count as an dropped frame. */
1284                 dev_kfree_skb(rx->skb);
1285
1286                 return RX_QUEUED;
1287         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1288                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1289                    ieee80211_has_pm(hdr->frame_control) &&
1290                    (ieee80211_is_data_qos(hdr->frame_control) ||
1291                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1292                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1293                 ac = ieee802_1d_to_ac[tid & 7];
1294
1295                 /*
1296                  * If this AC is not trigger-enabled do nothing.
1297                  *
1298                  * NB: This could/should check a separate bitmap of trigger-
1299                  * enabled queues, but for now we only implement uAPSD w/o
1300                  * TSPEC changes to the ACs, so they're always the same.
1301                  */
1302                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1303                         return RX_CONTINUE;
1304
1305                 /* if we are in a service period, do nothing */
1306                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1307                         return RX_CONTINUE;
1308
1309                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1310                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1311                 else
1312                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1313         }
1314
1315         return RX_CONTINUE;
1316 }
1317
1318 static ieee80211_rx_result debug_noinline
1319 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1320 {
1321         struct sta_info *sta = rx->sta;
1322         struct sk_buff *skb = rx->skb;
1323         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1324         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1325         int i;
1326
1327         if (!sta)
1328                 return RX_CONTINUE;
1329
1330         /*
1331          * Update last_rx only for IBSS packets which are for the current
1332          * BSSID and for station already AUTHORIZED to avoid keeping the
1333          * current IBSS network alive in cases where other STAs start
1334          * using different BSSID. This will also give the station another
1335          * chance to restart the authentication/authorization in case
1336          * something went wrong the first time.
1337          */
1338         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1339                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1340                                                 NL80211_IFTYPE_ADHOC);
1341                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1342                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1343                         sta->last_rx = jiffies;
1344                         if (ieee80211_is_data(hdr->frame_control) &&
1345                             !is_multicast_ether_addr(hdr->addr1)) {
1346                                 sta->last_rx_rate_idx = status->rate_idx;
1347                                 sta->last_rx_rate_flag = status->flag;
1348                                 sta->last_rx_rate_vht_flag = status->vht_flag;
1349                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1350                         }
1351                 }
1352         } else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
1353                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1354                                                 NL80211_IFTYPE_OCB);
1355                 /* OCB uses wild-card BSSID */
1356                 if (is_broadcast_ether_addr(bssid))
1357                         sta->last_rx = jiffies;
1358         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1359                 /*
1360                  * Mesh beacons will update last_rx when if they are found to
1361                  * match the current local configuration when processed.
1362                  */
1363                 sta->last_rx = jiffies;
1364                 if (ieee80211_is_data(hdr->frame_control)) {
1365                         sta->last_rx_rate_idx = status->rate_idx;
1366                         sta->last_rx_rate_flag = status->flag;
1367                         sta->last_rx_rate_vht_flag = status->vht_flag;
1368                         sta->last_rx_rate_vht_nss = status->vht_nss;
1369                 }
1370         }
1371
1372         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1373                 return RX_CONTINUE;
1374
1375         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1376                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1377
1378         sta->rx_fragments++;
1379         sta->rx_bytes += rx->skb->len;
1380         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1381                 sta->last_signal = status->signal;
1382                 ewma_add(&sta->avg_signal, -status->signal);
1383         }
1384
1385         if (status->chains) {
1386                 sta->chains = status->chains;
1387                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1388                         int signal = status->chain_signal[i];
1389
1390                         if (!(status->chains & BIT(i)))
1391                                 continue;
1392
1393                         sta->chain_signal_last[i] = signal;
1394                         ewma_add(&sta->chain_signal_avg[i], -signal);
1395                 }
1396         }
1397
1398         /*
1399          * Change STA power saving mode only at the end of a frame
1400          * exchange sequence.
1401          */
1402         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1403             !ieee80211_has_morefrags(hdr->frame_control) &&
1404             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1405             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1406              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1407             /* PM bit is only checked in frames where it isn't reserved,
1408              * in AP mode it's reserved in non-bufferable management frames
1409              * (cf. IEEE 802.11-2012 8.2.4.1.7 Power Management field)
1410              */
1411             (!ieee80211_is_mgmt(hdr->frame_control) ||
1412              ieee80211_is_bufferable_mmpdu(hdr->frame_control))) {
1413                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1414                         if (!ieee80211_has_pm(hdr->frame_control))
1415                                 sta_ps_end(sta);
1416                 } else {
1417                         if (ieee80211_has_pm(hdr->frame_control))
1418                                 sta_ps_start(sta);
1419                 }
1420         }
1421
1422         /* mesh power save support */
1423         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1424                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1425
1426         /*
1427          * Drop (qos-)data::nullfunc frames silently, since they
1428          * are used only to control station power saving mode.
1429          */
1430         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1431             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1432                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1433
1434                 /*
1435                  * If we receive a 4-addr nullfunc frame from a STA
1436                  * that was not moved to a 4-addr STA vlan yet send
1437                  * the event to userspace and for older hostapd drop
1438                  * the frame to the monitor interface.
1439                  */
1440                 if (ieee80211_has_a4(hdr->frame_control) &&
1441                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1442                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1443                       !rx->sdata->u.vlan.sta))) {
1444                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1445                                 cfg80211_rx_unexpected_4addr_frame(
1446                                         rx->sdata->dev, sta->sta.addr,
1447                                         GFP_ATOMIC);
1448                         return RX_DROP_MONITOR;
1449                 }
1450                 /*
1451                  * Update counter and free packet here to avoid
1452                  * counting this as a dropped packed.
1453                  */
1454                 sta->rx_packets++;
1455                 dev_kfree_skb(rx->skb);
1456                 return RX_QUEUED;
1457         }
1458
1459         return RX_CONTINUE;
1460 } /* ieee80211_rx_h_sta_process */
1461
1462 static ieee80211_rx_result debug_noinline
1463 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1464 {
1465         struct sk_buff *skb = rx->skb;
1466         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1467         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1468         int keyidx;
1469         int hdrlen;
1470         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1471         struct ieee80211_key *sta_ptk = NULL;
1472         int mmie_keyidx = -1;
1473         __le16 fc;
1474         const struct ieee80211_cipher_scheme *cs = NULL;
1475
1476         /*
1477          * Key selection 101
1478          *
1479          * There are four types of keys:
1480          *  - GTK (group keys)
1481          *  - IGTK (group keys for management frames)
1482          *  - PTK (pairwise keys)
1483          *  - STK (station-to-station pairwise keys)
1484          *
1485          * When selecting a key, we have to distinguish between multicast
1486          * (including broadcast) and unicast frames, the latter can only
1487          * use PTKs and STKs while the former always use GTKs and IGTKs.
1488          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1489          * unicast frames can also use key indices like GTKs. Hence, if we
1490          * don't have a PTK/STK we check the key index for a WEP key.
1491          *
1492          * Note that in a regular BSS, multicast frames are sent by the
1493          * AP only, associated stations unicast the frame to the AP first
1494          * which then multicasts it on their behalf.
1495          *
1496          * There is also a slight problem in IBSS mode: GTKs are negotiated
1497          * with each station, that is something we don't currently handle.
1498          * The spec seems to expect that one negotiates the same key with
1499          * every station but there's no such requirement; VLANs could be
1500          * possible.
1501          */
1502
1503         /*
1504          * No point in finding a key and decrypting if the frame is neither
1505          * addressed to us nor a multicast frame.
1506          */
1507         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1508                 return RX_CONTINUE;
1509
1510         /* start without a key */
1511         rx->key = NULL;
1512         fc = hdr->frame_control;
1513
1514         if (rx->sta) {
1515                 int keyid = rx->sta->ptk_idx;
1516
1517                 if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
1518                         cs = rx->sta->cipher_scheme;
1519                         keyid = iwl80211_get_cs_keyid(cs, rx->skb);
1520                         if (unlikely(keyid < 0))
1521                                 return RX_DROP_UNUSABLE;
1522                 }
1523                 sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
1524         }
1525
1526         if (!ieee80211_has_protected(fc))
1527                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1528
1529         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1530                 rx->key = sta_ptk;
1531                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1532                     (status->flag & RX_FLAG_IV_STRIPPED))
1533                         return RX_CONTINUE;
1534                 /* Skip decryption if the frame is not protected. */
1535                 if (!ieee80211_has_protected(fc))
1536                         return RX_CONTINUE;
1537         } else if (mmie_keyidx >= 0) {
1538                 /* Broadcast/multicast robust management frame / BIP */
1539                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1540                     (status->flag & RX_FLAG_IV_STRIPPED))
1541                         return RX_CONTINUE;
1542
1543                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1544                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1545                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1546                 if (rx->sta)
1547                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1548                 if (!rx->key)
1549                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1550         } else if (!ieee80211_has_protected(fc)) {
1551                 /*
1552                  * The frame was not protected, so skip decryption. However, we
1553                  * need to set rx->key if there is a key that could have been
1554                  * used so that the frame may be dropped if encryption would
1555                  * have been expected.
1556                  */
1557                 struct ieee80211_key *key = NULL;
1558                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1559                 int i;
1560
1561                 if (ieee80211_is_mgmt(fc) &&
1562                     is_multicast_ether_addr(hdr->addr1) &&
1563                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1564                         rx->key = key;
1565                 else {
1566                         if (rx->sta) {
1567                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1568                                         key = rcu_dereference(rx->sta->gtk[i]);
1569                                         if (key)
1570                                                 break;
1571                                 }
1572                         }
1573                         if (!key) {
1574                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1575                                         key = rcu_dereference(sdata->keys[i]);
1576                                         if (key)
1577                                                 break;
1578                                 }
1579                         }
1580                         if (key)
1581                                 rx->key = key;
1582                 }
1583                 return RX_CONTINUE;
1584         } else {
1585                 u8 keyid;
1586
1587                 /*
1588                  * The device doesn't give us the IV so we won't be
1589                  * able to look up the key. That's ok though, we
1590                  * don't need to decrypt the frame, we just won't
1591                  * be able to keep statistics accurate.
1592                  * Except for key threshold notifications, should
1593                  * we somehow allow the driver to tell us which key
1594                  * the hardware used if this flag is set?
1595                  */
1596                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1597                     (status->flag & RX_FLAG_IV_STRIPPED))
1598                         return RX_CONTINUE;
1599
1600                 hdrlen = ieee80211_hdrlen(fc);
1601
1602                 if (cs) {
1603                         keyidx = iwl80211_get_cs_keyid(cs, rx->skb);
1604
1605                         if (unlikely(keyidx < 0))
1606                                 return RX_DROP_UNUSABLE;
1607                 } else {
1608                         if (rx->skb->len < 8 + hdrlen)
1609                                 return RX_DROP_UNUSABLE; /* TODO: count this? */
1610                         /*
1611                          * no need to call ieee80211_wep_get_keyidx,
1612                          * it verifies a bunch of things we've done already
1613                          */
1614                         skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1615                         keyidx = keyid >> 6;
1616                 }
1617
1618                 /* check per-station GTK first, if multicast packet */
1619                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1620                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1621
1622                 /* if not found, try default key */
1623                 if (!rx->key) {
1624                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1625
1626                         /*
1627                          * RSNA-protected unicast frames should always be
1628                          * sent with pairwise or station-to-station keys,
1629                          * but for WEP we allow using a key index as well.
1630                          */
1631                         if (rx->key &&
1632                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1633                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1634                             !is_multicast_ether_addr(hdr->addr1))
1635                                 rx->key = NULL;
1636                 }
1637         }
1638
1639         if (rx->key) {
1640                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1641                         return RX_DROP_MONITOR;
1642
1643                 rx->key->tx_rx_count++;
1644                 /* TODO: add threshold stuff again */
1645         } else {
1646                 return RX_DROP_MONITOR;
1647         }
1648
1649         switch (rx->key->conf.cipher) {
1650         case WLAN_CIPHER_SUITE_WEP40:
1651         case WLAN_CIPHER_SUITE_WEP104:
1652                 result = ieee80211_crypto_wep_decrypt(rx);
1653                 break;
1654         case WLAN_CIPHER_SUITE_TKIP:
1655                 result = ieee80211_crypto_tkip_decrypt(rx);
1656                 break;
1657         case WLAN_CIPHER_SUITE_CCMP:
1658                 result = ieee80211_crypto_ccmp_decrypt(rx);
1659                 break;
1660         case WLAN_CIPHER_SUITE_AES_CMAC:
1661                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1662                 break;
1663         default:
1664                 result = ieee80211_crypto_hw_decrypt(rx);
1665         }
1666
1667         /* the hdr variable is invalid after the decrypt handlers */
1668
1669         /* either the frame has been decrypted or will be dropped */
1670         status->flag |= RX_FLAG_DECRYPTED;
1671
1672         return result;
1673 }
1674
1675 static inline struct ieee80211_fragment_entry *
1676 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1677                          unsigned int frag, unsigned int seq, int rx_queue,
1678                          struct sk_buff **skb)
1679 {
1680         struct ieee80211_fragment_entry *entry;
1681
1682         entry = &sdata->fragments[sdata->fragment_next++];
1683         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1684                 sdata->fragment_next = 0;
1685
1686         if (!skb_queue_empty(&entry->skb_list))
1687                 __skb_queue_purge(&entry->skb_list);
1688
1689         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1690         *skb = NULL;
1691         entry->first_frag_time = jiffies;
1692         entry->seq = seq;
1693         entry->rx_queue = rx_queue;
1694         entry->last_frag = frag;
1695         entry->ccmp = 0;
1696         entry->extra_len = 0;
1697
1698         return entry;
1699 }
1700
1701 static inline struct ieee80211_fragment_entry *
1702 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1703                           unsigned int frag, unsigned int seq,
1704                           int rx_queue, struct ieee80211_hdr *hdr)
1705 {
1706         struct ieee80211_fragment_entry *entry;
1707         int i, idx;
1708
1709         idx = sdata->fragment_next;
1710         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1711                 struct ieee80211_hdr *f_hdr;
1712
1713                 idx--;
1714                 if (idx < 0)
1715                         idx = IEEE80211_FRAGMENT_MAX - 1;
1716
1717                 entry = &sdata->fragments[idx];
1718                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1719                     entry->rx_queue != rx_queue ||
1720                     entry->last_frag + 1 != frag)
1721                         continue;
1722
1723                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1724
1725                 /*
1726                  * Check ftype and addresses are equal, else check next fragment
1727                  */
1728                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1729                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1730                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1731                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1732                         continue;
1733
1734                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1735                         __skb_queue_purge(&entry->skb_list);
1736                         continue;
1737                 }
1738                 return entry;
1739         }
1740
1741         return NULL;
1742 }
1743
1744 static ieee80211_rx_result debug_noinline
1745 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1746 {
1747         struct ieee80211_hdr *hdr;
1748         u16 sc;
1749         __le16 fc;
1750         unsigned int frag, seq;
1751         struct ieee80211_fragment_entry *entry;
1752         struct sk_buff *skb;
1753         struct ieee80211_rx_status *status;
1754
1755         hdr = (struct ieee80211_hdr *)rx->skb->data;
1756         fc = hdr->frame_control;
1757
1758         if (ieee80211_is_ctl(fc))
1759                 return RX_CONTINUE;
1760
1761         sc = le16_to_cpu(hdr->seq_ctrl);
1762         frag = sc & IEEE80211_SCTL_FRAG;
1763
1764         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1765                    is_multicast_ether_addr(hdr->addr1))) {
1766                 /* not fragmented */
1767                 goto out;
1768         }
1769         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1770
1771         if (skb_linearize(rx->skb))
1772                 return RX_DROP_UNUSABLE;
1773
1774         /*
1775          *  skb_linearize() might change the skb->data and
1776          *  previously cached variables (in this case, hdr) need to
1777          *  be refreshed with the new data.
1778          */
1779         hdr = (struct ieee80211_hdr *)rx->skb->data;
1780         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1781
1782         if (frag == 0) {
1783                 /* This is the first fragment of a new frame. */
1784                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1785                                                  rx->seqno_idx, &(rx->skb));
1786                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1787                     ieee80211_has_protected(fc)) {
1788                         int queue = rx->security_idx;
1789                         /* Store CCMP PN so that we can verify that the next
1790                          * fragment has a sequential PN value. */
1791                         entry->ccmp = 1;
1792                         memcpy(entry->last_pn,
1793                                rx->key->u.ccmp.rx_pn[queue],
1794                                IEEE80211_CCMP_PN_LEN);
1795                 }
1796                 return RX_QUEUED;
1797         }
1798
1799         /* This is a fragment for a frame that should already be pending in
1800          * fragment cache. Add this fragment to the end of the pending entry.
1801          */
1802         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1803                                           rx->seqno_idx, hdr);
1804         if (!entry) {
1805                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1806                 return RX_DROP_MONITOR;
1807         }
1808
1809         /* Verify that MPDUs within one MSDU have sequential PN values.
1810          * (IEEE 802.11i, 8.3.3.4.5) */
1811         if (entry->ccmp) {
1812                 int i;
1813                 u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
1814                 int queue;
1815                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1816                         return RX_DROP_UNUSABLE;
1817                 memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
1818                 for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
1819                         pn[i]++;
1820                         if (pn[i])
1821                                 break;
1822                 }
1823                 queue = rx->security_idx;
1824                 rpn = rx->key->u.ccmp.rx_pn[queue];
1825                 if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
1826                         return RX_DROP_UNUSABLE;
1827                 memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
1828         }
1829
1830         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1831         __skb_queue_tail(&entry->skb_list, rx->skb);
1832         entry->last_frag = frag;
1833         entry->extra_len += rx->skb->len;
1834         if (ieee80211_has_morefrags(fc)) {
1835                 rx->skb = NULL;
1836                 return RX_QUEUED;
1837         }
1838
1839         rx->skb = __skb_dequeue(&entry->skb_list);
1840         if (skb_tailroom(rx->skb) < entry->extra_len) {
1841                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1842                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1843                                               GFP_ATOMIC))) {
1844                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1845                         __skb_queue_purge(&entry->skb_list);
1846                         return RX_DROP_UNUSABLE;
1847                 }
1848         }
1849         while ((skb = __skb_dequeue(&entry->skb_list))) {
1850                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1851                 dev_kfree_skb(skb);
1852         }
1853
1854         /* Complete frame has been reassembled - process it now */
1855         status = IEEE80211_SKB_RXCB(rx->skb);
1856         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1857
1858  out:
1859         if (rx->sta)
1860                 rx->sta->rx_packets++;
1861         if (is_multicast_ether_addr(hdr->addr1))
1862                 rx->local->dot11MulticastReceivedFrameCount++;
1863         else
1864                 ieee80211_led_rx(rx->local);
1865         return RX_CONTINUE;
1866 }
1867
1868 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1869 {
1870         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1871                 return -EACCES;
1872
1873         return 0;
1874 }
1875
1876 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1877 {
1878         struct sk_buff *skb = rx->skb;
1879         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1880
1881         /*
1882          * Pass through unencrypted frames if the hardware has
1883          * decrypted them already.
1884          */
1885         if (status->flag & RX_FLAG_DECRYPTED)
1886                 return 0;
1887
1888         /* Drop unencrypted frames if key is set. */
1889         if (unlikely(!ieee80211_has_protected(fc) &&
1890                      !ieee80211_is_nullfunc(fc) &&
1891                      ieee80211_is_data(fc) &&
1892                      (rx->key || rx->sdata->drop_unencrypted)))
1893                 return -EACCES;
1894
1895         return 0;
1896 }
1897
1898 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1899 {
1900         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1901         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1902         __le16 fc = hdr->frame_control;
1903
1904         /*
1905          * Pass through unencrypted frames if the hardware has
1906          * decrypted them already.
1907          */
1908         if (status->flag & RX_FLAG_DECRYPTED)
1909                 return 0;
1910
1911         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1912                 if (unlikely(!ieee80211_has_protected(fc) &&
1913                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1914                              rx->key)) {
1915                         if (ieee80211_is_deauth(fc) ||
1916                             ieee80211_is_disassoc(fc))
1917                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
1918                                                              rx->skb->data,
1919                                                              rx->skb->len);
1920                         return -EACCES;
1921                 }
1922                 /* BIP does not use Protected field, so need to check MMIE */
1923                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1924                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1925                         if (ieee80211_is_deauth(fc) ||
1926                             ieee80211_is_disassoc(fc))
1927                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
1928                                                              rx->skb->data,
1929                                                              rx->skb->len);
1930                         return -EACCES;
1931                 }
1932                 /*
1933                  * When using MFP, Action frames are not allowed prior to
1934                  * having configured keys.
1935                  */
1936                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1937                              ieee80211_is_robust_mgmt_frame(rx->skb)))
1938                         return -EACCES;
1939         }
1940
1941         return 0;
1942 }
1943
1944 static int
1945 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1946 {
1947         struct ieee80211_sub_if_data *sdata = rx->sdata;
1948         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1949         bool check_port_control = false;
1950         struct ethhdr *ehdr;
1951         int ret;
1952
1953         *port_control = false;
1954         if (ieee80211_has_a4(hdr->frame_control) &&
1955             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1956                 return -1;
1957
1958         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1959             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1960
1961                 if (!sdata->u.mgd.use_4addr)
1962                         return -1;
1963                 else
1964                         check_port_control = true;
1965         }
1966
1967         if (is_multicast_ether_addr(hdr->addr1) &&
1968             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1969                 return -1;
1970
1971         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1972         if (ret < 0)
1973                 return ret;
1974
1975         ehdr = (struct ethhdr *) rx->skb->data;
1976         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1977                 *port_control = true;
1978         else if (check_port_control)
1979                 return -1;
1980
1981         return 0;
1982 }
1983
1984 /*
1985  * requires that rx->skb is a frame with ethernet header
1986  */
1987 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1988 {
1989         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1990                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1991         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1992
1993         /*
1994          * Allow EAPOL frames to us/the PAE group address regardless
1995          * of whether the frame was encrypted or not.
1996          */
1997         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1998             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1999              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
2000                 return true;
2001
2002         if (ieee80211_802_1x_port_control(rx) ||
2003             ieee80211_drop_unencrypted(rx, fc))
2004                 return false;
2005
2006         return true;
2007 }
2008
2009 /*
2010  * requires that rx->skb is a frame with ethernet header
2011  */
2012 static void
2013 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
2014 {
2015         struct ieee80211_sub_if_data *sdata = rx->sdata;
2016         struct net_device *dev = sdata->dev;
2017         struct sk_buff *skb, *xmit_skb;
2018         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2019         struct sta_info *dsta;
2020         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2021
2022         skb = rx->skb;
2023         xmit_skb = NULL;
2024
2025         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
2026              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
2027             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
2028             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
2029             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
2030                 if (is_multicast_ether_addr(ehdr->h_dest)) {
2031                         /*
2032                          * send multicast frames both to higher layers in
2033                          * local net stack and back to the wireless medium
2034                          */
2035                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
2036                         if (!xmit_skb)
2037                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
2038                                                     dev->name);
2039                 } else {
2040                         dsta = sta_info_get(sdata, skb->data);
2041                         if (dsta) {
2042                                 /*
2043                                  * The destination station is associated to
2044                                  * this AP (in this VLAN), so send the frame
2045                                  * directly to it and do not pass it to local
2046                                  * net stack.
2047                                  */
2048                                 xmit_skb = skb;
2049                                 skb = NULL;
2050                         }
2051                 }
2052         }
2053
2054 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2055         if (skb) {
2056                 /* 'align' will only take the values 0 or 2 here since all
2057                  * frames are required to be aligned to 2-byte boundaries
2058                  * when being passed to mac80211; the code here works just
2059                  * as well if that isn't true, but mac80211 assumes it can
2060                  * access fields as 2-byte aligned (e.g. for ether_addr_equal)
2061                  */
2062                 int align;
2063
2064                 align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
2065                 if (align) {
2066                         if (WARN_ON(skb_headroom(skb) < 3)) {
2067                                 dev_kfree_skb(skb);
2068                                 skb = NULL;
2069                         } else {
2070                                 u8 *data = skb->data;
2071                                 size_t len = skb_headlen(skb);
2072                                 skb->data -= align;
2073                                 memmove(skb->data, data, len);
2074                                 skb_set_tail_pointer(skb, len);
2075                         }
2076                 }
2077         }
2078 #endif
2079
2080         if (skb) {
2081                 /* deliver to local stack */
2082                 skb->protocol = eth_type_trans(skb, dev);
2083                 memset(skb->cb, 0, sizeof(skb->cb));
2084                 if (rx->local->napi)
2085                         napi_gro_receive(rx->local->napi, skb);
2086                 else
2087                         netif_receive_skb(skb);
2088         }
2089
2090         if (xmit_skb) {
2091                 /*
2092                  * Send to wireless media and increase priority by 256 to
2093                  * keep the received priority instead of reclassifying
2094                  * the frame (see cfg80211_classify8021d).
2095                  */
2096                 xmit_skb->priority += 256;
2097                 xmit_skb->protocol = htons(ETH_P_802_3);
2098                 skb_reset_network_header(xmit_skb);
2099                 skb_reset_mac_header(xmit_skb);
2100                 dev_queue_xmit(xmit_skb);
2101         }
2102 }
2103
2104 static ieee80211_rx_result debug_noinline
2105 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
2106 {
2107         struct net_device *dev = rx->sdata->dev;
2108         struct sk_buff *skb = rx->skb;
2109         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2110         __le16 fc = hdr->frame_control;
2111         struct sk_buff_head frame_list;
2112         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2113
2114         if (unlikely(!ieee80211_is_data(fc)))
2115                 return RX_CONTINUE;
2116
2117         if (unlikely(!ieee80211_is_data_present(fc)))
2118                 return RX_DROP_MONITOR;
2119
2120         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
2121                 return RX_CONTINUE;
2122
2123         if (ieee80211_has_a4(hdr->frame_control) &&
2124             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2125             !rx->sdata->u.vlan.sta)
2126                 return RX_DROP_UNUSABLE;
2127
2128         if (is_multicast_ether_addr(hdr->addr1) &&
2129             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2130               rx->sdata->u.vlan.sta) ||
2131              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
2132               rx->sdata->u.mgd.use_4addr)))
2133                 return RX_DROP_UNUSABLE;
2134
2135         skb->dev = dev;
2136         __skb_queue_head_init(&frame_list);
2137
2138         if (skb_linearize(skb))
2139                 return RX_DROP_UNUSABLE;
2140
2141         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
2142                                  rx->sdata->vif.type,
2143                                  rx->local->hw.extra_tx_headroom, true);
2144
2145         while (!skb_queue_empty(&frame_list)) {
2146                 rx->skb = __skb_dequeue(&frame_list);
2147
2148                 if (!ieee80211_frame_allowed(rx, fc)) {
2149                         dev_kfree_skb(rx->skb);
2150                         continue;
2151                 }
2152                 dev->stats.rx_packets++;
2153                 dev->stats.rx_bytes += rx->skb->len;
2154
2155                 ieee80211_deliver_skb(rx);
2156         }
2157
2158         return RX_QUEUED;
2159 }
2160
2161 #ifdef CONFIG_MAC80211_MESH
2162 static ieee80211_rx_result
2163 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2164 {
2165         struct ieee80211_hdr *fwd_hdr, *hdr;
2166         struct ieee80211_tx_info *info;
2167         struct ieee80211s_hdr *mesh_hdr;
2168         struct sk_buff *skb = rx->skb, *fwd_skb;
2169         struct ieee80211_local *local = rx->local;
2170         struct ieee80211_sub_if_data *sdata = rx->sdata;
2171         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2172         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2173         u16 q, hdrlen;
2174
2175         hdr = (struct ieee80211_hdr *) skb->data;
2176         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2177
2178         /* make sure fixed part of mesh header is there, also checks skb len */
2179         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2180                 return RX_DROP_MONITOR;
2181
2182         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2183
2184         /* make sure full mesh header is there, also checks skb len */
2185         if (!pskb_may_pull(rx->skb,
2186                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2187                 return RX_DROP_MONITOR;
2188
2189         /* reload pointers */
2190         hdr = (struct ieee80211_hdr *) skb->data;
2191         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2192
2193         /* frame is in RMC, don't forward */
2194         if (ieee80211_is_data(hdr->frame_control) &&
2195             is_multicast_ether_addr(hdr->addr1) &&
2196             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2197                 return RX_DROP_MONITOR;
2198
2199         if (!ieee80211_is_data(hdr->frame_control) ||
2200             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2201                 return RX_CONTINUE;
2202
2203         if (!mesh_hdr->ttl)
2204                 return RX_DROP_MONITOR;
2205
2206         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2207                 struct mesh_path *mppath;
2208                 char *proxied_addr;
2209                 char *mpp_addr;
2210
2211                 if (is_multicast_ether_addr(hdr->addr1)) {
2212                         mpp_addr = hdr->addr3;
2213                         proxied_addr = mesh_hdr->eaddr1;
2214                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2215                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2216                         mpp_addr = hdr->addr4;
2217                         proxied_addr = mesh_hdr->eaddr2;
2218                 } else {
2219                         return RX_DROP_MONITOR;
2220                 }
2221
2222                 rcu_read_lock();
2223                 mppath = mpp_path_lookup(sdata, proxied_addr);
2224                 if (!mppath) {
2225                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2226                 } else {
2227                         spin_lock_bh(&mppath->state_lock);
2228                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2229                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2230                         spin_unlock_bh(&mppath->state_lock);
2231                 }
2232                 rcu_read_unlock();
2233         }
2234
2235         /* Frame has reached destination.  Don't forward */
2236         if (!is_multicast_ether_addr(hdr->addr1) &&
2237             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2238                 return RX_CONTINUE;
2239
2240         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2241         if (ieee80211_queue_stopped(&local->hw, q)) {
2242                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2243                 return RX_DROP_MONITOR;
2244         }
2245         skb_set_queue_mapping(skb, q);
2246
2247         if (!--mesh_hdr->ttl) {
2248                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2249                 goto out;
2250         }
2251
2252         if (!ifmsh->mshcfg.dot11MeshForwarding)
2253                 goto out;
2254
2255         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2256         if (!fwd_skb) {
2257                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2258                                     sdata->name);
2259                 goto out;
2260         }
2261
2262         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2263         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2264         info = IEEE80211_SKB_CB(fwd_skb);
2265         memset(info, 0, sizeof(*info));
2266         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2267         info->control.vif = &rx->sdata->vif;
2268         info->control.jiffies = jiffies;
2269         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2270                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2271                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2272                 /* update power mode indication when forwarding */
2273                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2274         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2275                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2276                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2277         } else {
2278                 /* unable to resolve next hop */
2279                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2280                                    fwd_hdr->addr3, 0,
2281                                    WLAN_REASON_MESH_PATH_NOFORWARD,
2282                                    fwd_hdr->addr2);
2283                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2284                 kfree_skb(fwd_skb);
2285                 return RX_DROP_MONITOR;
2286         }
2287
2288         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2289         ieee80211_add_pending_skb(local, fwd_skb);
2290  out:
2291         if (is_multicast_ether_addr(hdr->addr1) ||
2292             sdata->dev->flags & IFF_PROMISC)
2293                 return RX_CONTINUE;
2294         else
2295                 return RX_DROP_MONITOR;
2296 }
2297 #endif
2298
2299 static ieee80211_rx_result debug_noinline
2300 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2301 {
2302         struct ieee80211_sub_if_data *sdata = rx->sdata;
2303         struct ieee80211_local *local = rx->local;
2304         struct net_device *dev = sdata->dev;
2305         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2306         __le16 fc = hdr->frame_control;
2307         bool port_control;
2308         int err;
2309
2310         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2311                 return RX_CONTINUE;
2312
2313         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2314                 return RX_DROP_MONITOR;
2315
2316         /*
2317          * Send unexpected-4addr-frame event to hostapd. For older versions,
2318          * also drop the frame to cooked monitor interfaces.
2319          */
2320         if (ieee80211_has_a4(hdr->frame_control) &&
2321             sdata->vif.type == NL80211_IFTYPE_AP) {
2322                 if (rx->sta &&
2323                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2324                         cfg80211_rx_unexpected_4addr_frame(
2325                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2326                 return RX_DROP_MONITOR;
2327         }
2328
2329         err = __ieee80211_data_to_8023(rx, &port_control);
2330         if (unlikely(err))
2331                 return RX_DROP_UNUSABLE;
2332
2333         if (!ieee80211_frame_allowed(rx, fc))
2334                 return RX_DROP_MONITOR;
2335
2336         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2337             unlikely(port_control) && sdata->bss) {
2338                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2339                                      u.ap);
2340                 dev = sdata->dev;
2341                 rx->sdata = sdata;
2342         }
2343
2344         rx->skb->dev = dev;
2345
2346         dev->stats.rx_packets++;
2347         dev->stats.rx_bytes += rx->skb->len;
2348
2349         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2350             !is_multicast_ether_addr(
2351                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2352             (!local->scanning &&
2353              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2354                         mod_timer(&local->dynamic_ps_timer, jiffies +
2355                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2356         }
2357
2358         ieee80211_deliver_skb(rx);
2359
2360         return RX_QUEUED;
2361 }
2362
2363 static ieee80211_rx_result debug_noinline
2364 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2365 {
2366         struct sk_buff *skb = rx->skb;
2367         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2368         struct tid_ampdu_rx *tid_agg_rx;
2369         u16 start_seq_num;
2370         u16 tid;
2371
2372         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2373                 return RX_CONTINUE;
2374
2375         if (ieee80211_is_back_req(bar->frame_control)) {
2376                 struct {
2377                         __le16 control, start_seq_num;
2378                 } __packed bar_data;
2379
2380                 if (!rx->sta)
2381                         return RX_DROP_MONITOR;
2382
2383                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2384                                   &bar_data, sizeof(bar_data)))
2385                         return RX_DROP_MONITOR;
2386
2387                 tid = le16_to_cpu(bar_data.control) >> 12;
2388
2389                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2390                 if (!tid_agg_rx)
2391                         return RX_DROP_MONITOR;
2392
2393                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2394
2395                 /* reset session timer */
2396                 if (tid_agg_rx->timeout)
2397                         mod_timer(&tid_agg_rx->session_timer,
2398                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2399
2400                 spin_lock(&tid_agg_rx->reorder_lock);
2401                 /* release stored frames up to start of BAR */
2402                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2403                                                  start_seq_num, frames);
2404                 spin_unlock(&tid_agg_rx->reorder_lock);
2405
2406                 kfree_skb(skb);
2407                 return RX_QUEUED;
2408         }
2409
2410         /*
2411          * After this point, we only want management frames,
2412          * so we can drop all remaining control frames to
2413          * cooked monitor interfaces.
2414          */
2415         return RX_DROP_MONITOR;
2416 }
2417
2418 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2419                                            struct ieee80211_mgmt *mgmt,
2420                                            size_t len)
2421 {
2422         struct ieee80211_local *local = sdata->local;
2423         struct sk_buff *skb;
2424         struct ieee80211_mgmt *resp;
2425
2426         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2427                 /* Not to own unicast address */
2428                 return;
2429         }
2430
2431         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2432             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2433                 /* Not from the current AP or not associated yet. */
2434                 return;
2435         }
2436
2437         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2438                 /* Too short SA Query request frame */
2439                 return;
2440         }
2441
2442         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2443         if (skb == NULL)
2444                 return;
2445
2446         skb_reserve(skb, local->hw.extra_tx_headroom);
2447         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2448         memset(resp, 0, 24);
2449         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2450         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2451         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2452         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2453                                           IEEE80211_STYPE_ACTION);
2454         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2455         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2456         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2457         memcpy(resp->u.action.u.sa_query.trans_id,
2458                mgmt->u.action.u.sa_query.trans_id,
2459                WLAN_SA_QUERY_TR_ID_LEN);
2460
2461         ieee80211_tx_skb(sdata, skb);
2462 }
2463
2464 static ieee80211_rx_result debug_noinline
2465 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2466 {
2467         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2468         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2469
2470         /*
2471          * From here on, look only at management frames.
2472          * Data and control frames are already handled,
2473          * and unknown (reserved) frames are useless.
2474          */
2475         if (rx->skb->len < 24)
2476                 return RX_DROP_MONITOR;
2477
2478         if (!ieee80211_is_mgmt(mgmt->frame_control))
2479                 return RX_DROP_MONITOR;
2480
2481         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2482             ieee80211_is_beacon(mgmt->frame_control) &&
2483             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2484                 int sig = 0;
2485
2486                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2487                         sig = status->signal;
2488
2489                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2490                                             rx->skb->data, rx->skb->len,
2491                                             status->freq, sig);
2492                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2493         }
2494
2495         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2496                 return RX_DROP_MONITOR;
2497
2498         if (ieee80211_drop_unencrypted_mgmt(rx))
2499                 return RX_DROP_UNUSABLE;
2500
2501         return RX_CONTINUE;
2502 }
2503
2504 static ieee80211_rx_result debug_noinline
2505 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2506 {
2507         struct ieee80211_local *local = rx->local;
2508         struct ieee80211_sub_if_data *sdata = rx->sdata;
2509         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2510         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2511         int len = rx->skb->len;
2512
2513         if (!ieee80211_is_action(mgmt->frame_control))
2514                 return RX_CONTINUE;
2515
2516         /* drop too small frames */
2517         if (len < IEEE80211_MIN_ACTION_SIZE)
2518                 return RX_DROP_UNUSABLE;
2519
2520         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2521             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
2522             mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
2523                 return RX_DROP_UNUSABLE;
2524
2525         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2526                 return RX_DROP_UNUSABLE;
2527
2528         switch (mgmt->u.action.category) {
2529         case WLAN_CATEGORY_HT:
2530                 /* reject HT action frames from stations not supporting HT */
2531                 if (!rx->sta->sta.ht_cap.ht_supported)
2532                         goto invalid;
2533
2534                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2535                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2536                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2537                     sdata->vif.type != NL80211_IFTYPE_AP &&
2538                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2539                         break;
2540
2541                 /* verify action & smps_control/chanwidth are present */
2542                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2543                         goto invalid;
2544
2545                 switch (mgmt->u.action.u.ht_smps.action) {
2546                 case WLAN_HT_ACTION_SMPS: {
2547                         struct ieee80211_supported_band *sband;
2548                         enum ieee80211_smps_mode smps_mode;
2549
2550                         /* convert to HT capability */
2551                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2552                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2553                                 smps_mode = IEEE80211_SMPS_OFF;
2554                                 break;
2555                         case WLAN_HT_SMPS_CONTROL_STATIC:
2556                                 smps_mode = IEEE80211_SMPS_STATIC;
2557                                 break;
2558                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2559                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2560                                 break;
2561                         default:
2562                                 goto invalid;
2563                         }
2564
2565                         /* if no change do nothing */
2566                         if (rx->sta->sta.smps_mode == smps_mode)
2567                                 goto handled;
2568                         rx->sta->sta.smps_mode = smps_mode;
2569
2570                         sband = rx->local->hw.wiphy->bands[status->band];
2571
2572                         rate_control_rate_update(local, sband, rx->sta,
2573                                                  IEEE80211_RC_SMPS_CHANGED);
2574                         goto handled;
2575                 }
2576                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2577                         struct ieee80211_supported_band *sband;
2578                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2579                         enum ieee80211_sta_rx_bandwidth new_bw;
2580
2581                         /* If it doesn't support 40 MHz it can't change ... */
2582                         if (!(rx->sta->sta.ht_cap.cap &
2583                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2584                                 goto handled;
2585
2586                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2587                                 new_bw = IEEE80211_STA_RX_BW_20;
2588                         else
2589                                 new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2590
2591                         if (rx->sta->sta.bandwidth == new_bw)
2592                                 goto handled;
2593
2594                         sband = rx->local->hw.wiphy->bands[status->band];
2595
2596                         rate_control_rate_update(local, sband, rx->sta,
2597                                                  IEEE80211_RC_BW_CHANGED);
2598                         goto handled;
2599                 }
2600                 default:
2601                         goto invalid;
2602                 }
2603
2604                 break;
2605         case WLAN_CATEGORY_PUBLIC:
2606                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2607                         goto invalid;
2608                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2609                         break;
2610                 if (!rx->sta)
2611                         break;
2612                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2613                         break;
2614                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2615                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2616                         break;
2617                 if (len < offsetof(struct ieee80211_mgmt,
2618                                    u.action.u.ext_chan_switch.variable))
2619                         goto invalid;
2620                 goto queue;
2621         case WLAN_CATEGORY_VHT:
2622                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2623                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2624                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2625                     sdata->vif.type != NL80211_IFTYPE_AP &&
2626                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2627                         break;
2628
2629                 /* verify action code is present */
2630                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2631                         goto invalid;
2632
2633                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2634                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2635                         u8 opmode;
2636
2637                         /* verify opmode is present */
2638                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2639                                 goto invalid;
2640
2641                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2642
2643                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2644                                                     opmode, status->band,
2645                                                     false);
2646                         goto handled;
2647                 }
2648                 default:
2649                         break;
2650                 }
2651                 break;
2652         case WLAN_CATEGORY_BACK:
2653                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2654                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2655                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2656                     sdata->vif.type != NL80211_IFTYPE_AP &&
2657                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2658                         break;
2659
2660                 /* verify action_code is present */
2661                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2662                         break;
2663
2664                 switch (mgmt->u.action.u.addba_req.action_code) {
2665                 case WLAN_ACTION_ADDBA_REQ:
2666                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2667                                    sizeof(mgmt->u.action.u.addba_req)))
2668                                 goto invalid;
2669                         break;
2670                 case WLAN_ACTION_ADDBA_RESP:
2671                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2672                                    sizeof(mgmt->u.action.u.addba_resp)))
2673                                 goto invalid;
2674                         break;
2675                 case WLAN_ACTION_DELBA:
2676                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2677                                    sizeof(mgmt->u.action.u.delba)))
2678                                 goto invalid;
2679                         break;
2680                 default:
2681                         goto invalid;
2682                 }
2683
2684                 goto queue;
2685         case WLAN_CATEGORY_SPECTRUM_MGMT:
2686                 /* verify action_code is present */
2687                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2688                         break;
2689
2690                 switch (mgmt->u.action.u.measurement.action_code) {
2691                 case WLAN_ACTION_SPCT_MSR_REQ:
2692                         if (status->band != IEEE80211_BAND_5GHZ)
2693                                 break;
2694
2695                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2696                                    sizeof(mgmt->u.action.u.measurement)))
2697                                 break;
2698
2699                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2700                                 break;
2701
2702                         ieee80211_process_measurement_req(sdata, mgmt, len);
2703                         goto handled;
2704                 case WLAN_ACTION_SPCT_CHL_SWITCH: {
2705                         u8 *bssid;
2706                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2707                                    sizeof(mgmt->u.action.u.chan_switch)))
2708                                 break;
2709
2710                         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2711                             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2712                             sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2713                                 break;
2714
2715                         if (sdata->vif.type == NL80211_IFTYPE_STATION)
2716                                 bssid = sdata->u.mgd.bssid;
2717                         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
2718                                 bssid = sdata->u.ibss.bssid;
2719                         else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
2720                                 bssid = mgmt->sa;
2721                         else
2722                                 break;
2723
2724                         if (!ether_addr_equal(mgmt->bssid, bssid))
2725                                 break;
2726
2727                         goto queue;
2728                         }
2729                 }
2730                 break;
2731         case WLAN_CATEGORY_SA_QUERY:
2732                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2733                            sizeof(mgmt->u.action.u.sa_query)))
2734                         break;
2735
2736                 switch (mgmt->u.action.u.sa_query.action) {
2737                 case WLAN_ACTION_SA_QUERY_REQUEST:
2738                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2739                                 break;
2740                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2741                         goto handled;
2742                 }
2743                 break;
2744         case WLAN_CATEGORY_SELF_PROTECTED:
2745                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2746                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2747                         break;
2748
2749                 switch (mgmt->u.action.u.self_prot.action_code) {
2750                 case WLAN_SP_MESH_PEERING_OPEN:
2751                 case WLAN_SP_MESH_PEERING_CLOSE:
2752                 case WLAN_SP_MESH_PEERING_CONFIRM:
2753                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2754                                 goto invalid;
2755                         if (sdata->u.mesh.user_mpm)
2756                                 /* userspace handles this frame */
2757                                 break;
2758                         goto queue;
2759                 case WLAN_SP_MGK_INFORM:
2760                 case WLAN_SP_MGK_ACK:
2761                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2762                                 goto invalid;
2763                         break;
2764                 }
2765                 break;
2766         case WLAN_CATEGORY_MESH_ACTION:
2767                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2768                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2769                         break;
2770
2771                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2772                         break;
2773                 if (mesh_action_is_path_sel(mgmt) &&
2774                     !mesh_path_sel_is_hwmp(sdata))
2775                         break;
2776                 goto queue;
2777         }
2778
2779         return RX_CONTINUE;
2780
2781  invalid:
2782         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2783         /* will return in the next handlers */
2784         return RX_CONTINUE;
2785
2786  handled:
2787         if (rx->sta)
2788                 rx->sta->rx_packets++;
2789         dev_kfree_skb(rx->skb);
2790         return RX_QUEUED;
2791
2792  queue:
2793         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2794         skb_queue_tail(&sdata->skb_queue, rx->skb);
2795         ieee80211_queue_work(&local->hw, &sdata->work);
2796         if (rx->sta)
2797                 rx->sta->rx_packets++;
2798         return RX_QUEUED;
2799 }
2800
2801 static ieee80211_rx_result debug_noinline
2802 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2803 {
2804         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2805         int sig = 0;
2806
2807         /* skip known-bad action frames and return them in the next handler */
2808         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2809                 return RX_CONTINUE;
2810
2811         /*
2812          * Getting here means the kernel doesn't know how to handle
2813          * it, but maybe userspace does ... include returned frames
2814          * so userspace can register for those to know whether ones
2815          * it transmitted were processed or returned.
2816          */
2817
2818         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2819                 sig = status->signal;
2820
2821         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2822                              rx->skb->data, rx->skb->len, 0)) {
2823                 if (rx->sta)
2824                         rx->sta->rx_packets++;
2825                 dev_kfree_skb(rx->skb);
2826                 return RX_QUEUED;
2827         }
2828
2829         return RX_CONTINUE;
2830 }
2831
2832 static ieee80211_rx_result debug_noinline
2833 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2834 {
2835         struct ieee80211_local *local = rx->local;
2836         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2837         struct sk_buff *nskb;
2838         struct ieee80211_sub_if_data *sdata = rx->sdata;
2839         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2840
2841         if (!ieee80211_is_action(mgmt->frame_control))
2842                 return RX_CONTINUE;
2843
2844         /*
2845          * For AP mode, hostapd is responsible for handling any action
2846          * frames that we didn't handle, including returning unknown
2847          * ones. For all other modes we will return them to the sender,
2848          * setting the 0x80 bit in the action category, as required by
2849          * 802.11-2012 9.24.4.
2850          * Newer versions of hostapd shall also use the management frame
2851          * registration mechanisms, but older ones still use cooked
2852          * monitor interfaces so push all frames there.
2853          */
2854         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2855             (sdata->vif.type == NL80211_IFTYPE_AP ||
2856              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2857                 return RX_DROP_MONITOR;
2858
2859         if (is_multicast_ether_addr(mgmt->da))
2860                 return RX_DROP_MONITOR;
2861
2862         /* do not return rejected action frames */
2863         if (mgmt->u.action.category & 0x80)
2864                 return RX_DROP_UNUSABLE;
2865
2866         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2867                                GFP_ATOMIC);
2868         if (nskb) {
2869                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2870
2871                 nmgmt->u.action.category |= 0x80;
2872                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2873                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2874
2875                 memset(nskb->cb, 0, sizeof(nskb->cb));
2876
2877                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2878                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2879
2880                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2881                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2882                                       IEEE80211_TX_CTL_NO_CCK_RATE;
2883                         if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2884                                 info->hw_queue =
2885                                         local->hw.offchannel_tx_hw_queue;
2886                 }
2887
2888                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2889                                             status->band);
2890         }
2891         dev_kfree_skb(rx->skb);
2892         return RX_QUEUED;
2893 }
2894
2895 static ieee80211_rx_result debug_noinline
2896 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2897 {
2898         struct ieee80211_sub_if_data *sdata = rx->sdata;
2899         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2900         __le16 stype;
2901
2902         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2903
2904         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2905             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2906             sdata->vif.type != NL80211_IFTYPE_OCB &&
2907             sdata->vif.type != NL80211_IFTYPE_STATION)
2908                 return RX_DROP_MONITOR;
2909
2910         switch (stype) {
2911         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2912         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2913         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2914                 /* process for all: mesh, mlme, ibss */
2915                 break;
2916         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2917         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2918         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2919         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2920                 if (is_multicast_ether_addr(mgmt->da) &&
2921                     !is_broadcast_ether_addr(mgmt->da))
2922                         return RX_DROP_MONITOR;
2923
2924                 /* process only for station */
2925                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2926                         return RX_DROP_MONITOR;
2927                 break;
2928         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2929                 /* process only for ibss and mesh */
2930                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2931                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2932                         return RX_DROP_MONITOR;
2933                 break;
2934         default:
2935                 return RX_DROP_MONITOR;
2936         }
2937
2938         /* queue up frame and kick off work to process it */
2939         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2940         skb_queue_tail(&sdata->skb_queue, rx->skb);
2941         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2942         if (rx->sta)
2943                 rx->sta->rx_packets++;
2944
2945         return RX_QUEUED;
2946 }
2947
2948 /* TODO: use IEEE80211_RX_FRAGMENTED */
2949 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2950                                         struct ieee80211_rate *rate)
2951 {
2952         struct ieee80211_sub_if_data *sdata;
2953         struct ieee80211_local *local = rx->local;
2954         struct sk_buff *skb = rx->skb, *skb2;
2955         struct net_device *prev_dev = NULL;
2956         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2957         int needed_headroom;
2958
2959         /*
2960          * If cooked monitor has been processed already, then
2961          * don't do it again. If not, set the flag.
2962          */
2963         if (rx->flags & IEEE80211_RX_CMNTR)
2964                 goto out_free_skb;
2965         rx->flags |= IEEE80211_RX_CMNTR;
2966
2967         /* If there are no cooked monitor interfaces, just free the SKB */
2968         if (!local->cooked_mntrs)
2969                 goto out_free_skb;
2970
2971         /* vendor data is long removed here */
2972         status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
2973         /* room for the radiotap header based on driver features */
2974         needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
2975
2976         if (skb_headroom(skb) < needed_headroom &&
2977             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2978                 goto out_free_skb;
2979
2980         /* prepend radiotap information */
2981         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2982                                          false);
2983
2984         skb_set_mac_header(skb, 0);
2985         skb->ip_summed = CHECKSUM_UNNECESSARY;
2986         skb->pkt_type = PACKET_OTHERHOST;
2987         skb->protocol = htons(ETH_P_802_2);
2988
2989         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2990                 if (!ieee80211_sdata_running(sdata))
2991                         continue;
2992
2993                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2994                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2995                         continue;
2996
2997                 if (prev_dev) {
2998                         skb2 = skb_clone(skb, GFP_ATOMIC);
2999                         if (skb2) {
3000                                 skb2->dev = prev_dev;
3001                                 netif_receive_skb(skb2);
3002                         }
3003                 }
3004
3005                 prev_dev = sdata->dev;
3006                 sdata->dev->stats.rx_packets++;
3007                 sdata->dev->stats.rx_bytes += skb->len;
3008         }
3009
3010         if (prev_dev) {
3011                 skb->dev = prev_dev;
3012                 netif_receive_skb(skb);
3013                 return;
3014         }
3015
3016  out_free_skb:
3017         dev_kfree_skb(skb);
3018 }
3019
3020 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
3021                                          ieee80211_rx_result res)
3022 {
3023         switch (res) {
3024         case RX_DROP_MONITOR:
3025                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3026                 if (rx->sta)
3027                         rx->sta->rx_dropped++;
3028                 /* fall through */
3029         case RX_CONTINUE: {
3030                 struct ieee80211_rate *rate = NULL;
3031                 struct ieee80211_supported_band *sband;
3032                 struct ieee80211_rx_status *status;
3033
3034                 status = IEEE80211_SKB_RXCB((rx->skb));
3035
3036                 sband = rx->local->hw.wiphy->bands[status->band];
3037                 if (!(status->flag & RX_FLAG_HT) &&
3038                     !(status->flag & RX_FLAG_VHT))
3039                         rate = &sband->bitrates[status->rate_idx];
3040
3041                 ieee80211_rx_cooked_monitor(rx, rate);
3042                 break;
3043                 }
3044         case RX_DROP_UNUSABLE:
3045                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3046                 if (rx->sta)
3047                         rx->sta->rx_dropped++;
3048                 dev_kfree_skb(rx->skb);
3049                 break;
3050         case RX_QUEUED:
3051                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
3052                 break;
3053         }
3054 }
3055
3056 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
3057                                   struct sk_buff_head *frames)
3058 {
3059         ieee80211_rx_result res = RX_DROP_MONITOR;
3060         struct sk_buff *skb;
3061
3062 #define CALL_RXH(rxh)                   \
3063         do {                            \
3064                 res = rxh(rx);          \
3065                 if (res != RX_CONTINUE) \
3066                         goto rxh_next;  \
3067         } while (0);
3068
3069         spin_lock_bh(&rx->local->rx_path_lock);
3070
3071         while ((skb = __skb_dequeue(frames))) {
3072                 /*
3073                  * all the other fields are valid across frames
3074                  * that belong to an aMPDU since they are on the
3075                  * same TID from the same station
3076                  */
3077                 rx->skb = skb;
3078
3079                 CALL_RXH(ieee80211_rx_h_check_more_data)
3080                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
3081                 CALL_RXH(ieee80211_rx_h_sta_process)
3082                 CALL_RXH(ieee80211_rx_h_decrypt)
3083                 CALL_RXH(ieee80211_rx_h_defragment)
3084                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
3085                 /* must be after MMIC verify so header is counted in MPDU mic */
3086 #ifdef CONFIG_MAC80211_MESH
3087                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
3088                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
3089 #endif
3090                 CALL_RXH(ieee80211_rx_h_amsdu)
3091                 CALL_RXH(ieee80211_rx_h_data)
3092
3093                 /* special treatment -- needs the queue */
3094                 res = ieee80211_rx_h_ctrl(rx, frames);
3095                 if (res != RX_CONTINUE)
3096                         goto rxh_next;
3097
3098                 CALL_RXH(ieee80211_rx_h_mgmt_check)
3099                 CALL_RXH(ieee80211_rx_h_action)
3100                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
3101                 CALL_RXH(ieee80211_rx_h_action_return)
3102                 CALL_RXH(ieee80211_rx_h_mgmt)
3103
3104  rxh_next:
3105                 ieee80211_rx_handlers_result(rx, res);
3106
3107 #undef CALL_RXH
3108         }
3109
3110         spin_unlock_bh(&rx->local->rx_path_lock);
3111 }
3112
3113 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
3114 {
3115         struct sk_buff_head reorder_release;
3116         ieee80211_rx_result res = RX_DROP_MONITOR;
3117
3118         __skb_queue_head_init(&reorder_release);
3119
3120 #define CALL_RXH(rxh)                   \
3121         do {                            \
3122                 res = rxh(rx);          \
3123                 if (res != RX_CONTINUE) \
3124                         goto rxh_next;  \
3125         } while (0);
3126
3127         CALL_RXH(ieee80211_rx_h_check_dup)
3128         CALL_RXH(ieee80211_rx_h_check)
3129
3130         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
3131
3132         ieee80211_rx_handlers(rx, &reorder_release);
3133         return;
3134
3135  rxh_next:
3136         ieee80211_rx_handlers_result(rx, res);
3137
3138 #undef CALL_RXH
3139 }
3140
3141 /*
3142  * This function makes calls into the RX path, therefore
3143  * it has to be invoked under RCU read lock.
3144  */
3145 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
3146 {
3147         struct sk_buff_head frames;
3148         struct ieee80211_rx_data rx = {
3149                 .sta = sta,
3150                 .sdata = sta->sdata,
3151                 .local = sta->local,
3152                 /* This is OK -- must be QoS data frame */
3153                 .security_idx = tid,
3154                 .seqno_idx = tid,
3155                 .flags = 0,
3156         };
3157         struct tid_ampdu_rx *tid_agg_rx;
3158
3159         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3160         if (!tid_agg_rx)
3161                 return;
3162
3163         __skb_queue_head_init(&frames);
3164
3165         spin_lock(&tid_agg_rx->reorder_lock);
3166         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3167         spin_unlock(&tid_agg_rx->reorder_lock);
3168
3169         ieee80211_rx_handlers(&rx, &frames);
3170 }
3171
3172 /* main receive path */
3173
3174 static bool prepare_for_handlers(struct ieee80211_rx_data *rx,
3175                                  struct ieee80211_hdr *hdr)
3176 {
3177         struct ieee80211_sub_if_data *sdata = rx->sdata;
3178         struct sk_buff *skb = rx->skb;
3179         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3180         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
3181         int multicast = is_multicast_ether_addr(hdr->addr1);
3182
3183         switch (sdata->vif.type) {
3184         case NL80211_IFTYPE_STATION:
3185                 if (!bssid && !sdata->u.mgd.use_4addr)
3186                         return false;
3187                 if (!multicast &&
3188                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3189                         if (!(sdata->dev->flags & IFF_PROMISC) ||
3190                             sdata->u.mgd.use_4addr)
3191                                 return false;
3192                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3193                 }
3194                 break;
3195         case NL80211_IFTYPE_ADHOC:
3196                 if (!bssid)
3197                         return false;
3198                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3199                     ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3200                         return false;
3201                 if (ieee80211_is_beacon(hdr->frame_control)) {
3202                         return true;
3203                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3204                         return false;
3205                 } else if (!multicast &&
3206                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3207                         if (!(sdata->dev->flags & IFF_PROMISC))
3208                                 return false;
3209                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3210                 } else if (!rx->sta) {
3211                         int rate_idx;
3212                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3213                                 rate_idx = 0; /* TODO: HT/VHT rates */
3214                         else
3215                                 rate_idx = status->rate_idx;
3216                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3217                                                  BIT(rate_idx));
3218                 }
3219                 break;
3220         case NL80211_IFTYPE_OCB:
3221                 if (!bssid)
3222                         return false;
3223                 if (ieee80211_is_beacon(hdr->frame_control)) {
3224                         return false;
3225                 } else if (!is_broadcast_ether_addr(bssid)) {
3226                         ocb_dbg(sdata, "BSSID mismatch in OCB mode!\n");
3227                         return false;
3228                 } else if (!multicast &&
3229                            !ether_addr_equal(sdata->dev->dev_addr,
3230                                              hdr->addr1)) {
3231                         /* if we are in promisc mode we also accept
3232                          * packets not destined for us
3233                          */
3234                         if (!(sdata->dev->flags & IFF_PROMISC))
3235                                 return false;
3236                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
3237                 } else if (!rx->sta) {
3238                         int rate_idx;
3239                         if (status->flag & RX_FLAG_HT)
3240                                 rate_idx = 0; /* TODO: HT rates */
3241                         else
3242                                 rate_idx = status->rate_idx;
3243                         ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
3244                                                 BIT(rate_idx));
3245                 }
3246                 break;
3247         case NL80211_IFTYPE_MESH_POINT:
3248                 if (!multicast &&
3249                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3250                         if (!(sdata->dev->flags & IFF_PROMISC))
3251                                 return false;
3252
3253                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3254                 }
3255                 break;
3256         case NL80211_IFTYPE_AP_VLAN:
3257         case NL80211_IFTYPE_AP:
3258                 if (!bssid) {
3259                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3260                                 return false;
3261                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3262                         /*
3263                          * Accept public action frames even when the
3264                          * BSSID doesn't match, this is used for P2P
3265                          * and location updates. Note that mac80211
3266                          * itself never looks at these frames.
3267                          */
3268                         if (!multicast &&
3269                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3270                                 return false;
3271                         if (ieee80211_is_public_action(hdr, skb->len))
3272                                 return true;
3273                         if (!ieee80211_is_beacon(hdr->frame_control))
3274                                 return false;
3275                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3276                 } else if (!ieee80211_has_tods(hdr->frame_control)) {
3277                         /* ignore data frames to TDLS-peers */
3278                         if (ieee80211_is_data(hdr->frame_control))
3279                                 return false;
3280                         /* ignore action frames to TDLS-peers */
3281                         if (ieee80211_is_action(hdr->frame_control) &&
3282                             !ether_addr_equal(bssid, hdr->addr1))
3283                                 return false;
3284                 }
3285                 break;
3286         case NL80211_IFTYPE_WDS:
3287                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3288                         return false;
3289                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3290                         return false;
3291                 break;
3292         case NL80211_IFTYPE_P2P_DEVICE:
3293                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3294                     !ieee80211_is_probe_req(hdr->frame_control) &&
3295                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3296                     !ieee80211_is_beacon(hdr->frame_control))
3297                         return false;
3298                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3299                     !multicast)
3300                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3301                 break;
3302         default:
3303                 /* should never get here */
3304                 WARN_ON_ONCE(1);
3305                 break;
3306         }
3307
3308         return true;
3309 }
3310
3311 /*
3312  * This function returns whether or not the SKB
3313  * was destined for RX processing or not, which,
3314  * if consume is true, is equivalent to whether
3315  * or not the skb was consumed.
3316  */
3317 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3318                                             struct sk_buff *skb, bool consume)
3319 {
3320         struct ieee80211_local *local = rx->local;
3321         struct ieee80211_sub_if_data *sdata = rx->sdata;
3322         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3323         struct ieee80211_hdr *hdr = (void *)skb->data;
3324
3325         rx->skb = skb;
3326         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3327
3328         if (!prepare_for_handlers(rx, hdr))
3329                 return false;
3330
3331         if (!consume) {
3332                 skb = skb_copy(skb, GFP_ATOMIC);
3333                 if (!skb) {
3334                         if (net_ratelimit())
3335                                 wiphy_debug(local->hw.wiphy,
3336                                         "failed to copy skb for %s\n",
3337                                         sdata->name);
3338                         return true;
3339                 }
3340
3341                 rx->skb = skb;
3342         }
3343
3344         ieee80211_invoke_rx_handlers(rx);
3345         return true;
3346 }
3347
3348 /*
3349  * This is the actual Rx frames handler. as it belongs to Rx path it must
3350  * be called with rcu_read_lock protection.
3351  */
3352 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3353                                          struct sk_buff *skb)
3354 {
3355         struct ieee80211_local *local = hw_to_local(hw);
3356         struct ieee80211_sub_if_data *sdata;
3357         struct ieee80211_hdr *hdr;
3358         __le16 fc;
3359         struct ieee80211_rx_data rx;
3360         struct ieee80211_sub_if_data *prev;
3361         struct sta_info *sta, *tmp, *prev_sta;
3362         int err = 0;
3363
3364         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3365         memset(&rx, 0, sizeof(rx));
3366         rx.skb = skb;
3367         rx.local = local;
3368
3369         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3370                 local->dot11ReceivedFragmentCount++;
3371
3372         if (ieee80211_is_mgmt(fc)) {
3373                 /* drop frame if too short for header */
3374                 if (skb->len < ieee80211_hdrlen(fc))
3375                         err = -ENOBUFS;
3376                 else
3377                         err = skb_linearize(skb);
3378         } else {
3379                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3380         }
3381
3382         if (err) {
3383                 dev_kfree_skb(skb);
3384                 return;
3385         }
3386
3387         hdr = (struct ieee80211_hdr *)skb->data;
3388         ieee80211_parse_qos(&rx);
3389         ieee80211_verify_alignment(&rx);
3390
3391         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3392                      ieee80211_is_beacon(hdr->frame_control)))
3393                 ieee80211_scan_rx(local, skb);
3394
3395         if (ieee80211_is_data(fc)) {
3396                 prev_sta = NULL;
3397
3398                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3399                         if (!prev_sta) {
3400                                 prev_sta = sta;
3401                                 continue;
3402                         }
3403
3404                         rx.sta = prev_sta;
3405                         rx.sdata = prev_sta->sdata;
3406                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3407
3408                         prev_sta = sta;
3409                 }
3410
3411                 if (prev_sta) {
3412                         rx.sta = prev_sta;
3413                         rx.sdata = prev_sta->sdata;
3414
3415                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3416                                 return;
3417                         goto out;
3418                 }
3419         }
3420
3421         prev = NULL;
3422
3423         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3424                 if (!ieee80211_sdata_running(sdata))
3425                         continue;
3426
3427                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3428                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3429                         continue;
3430
3431                 /*
3432                  * frame is destined for this interface, but if it's
3433                  * not also for the previous one we handle that after
3434                  * the loop to avoid copying the SKB once too much
3435                  */
3436
3437                 if (!prev) {
3438                         prev = sdata;
3439                         continue;
3440                 }
3441
3442                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3443                 rx.sdata = prev;
3444                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3445
3446                 prev = sdata;
3447         }
3448
3449         if (prev) {
3450                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3451                 rx.sdata = prev;
3452
3453                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3454                         return;
3455         }
3456
3457  out:
3458         dev_kfree_skb(skb);
3459 }
3460
3461 /*
3462  * This is the receive path handler. It is called by a low level driver when an
3463  * 802.11 MPDU is received from the hardware.
3464  */
3465 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3466 {
3467         struct ieee80211_local *local = hw_to_local(hw);
3468         struct ieee80211_rate *rate = NULL;
3469         struct ieee80211_supported_band *sband;
3470         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3471
3472         WARN_ON_ONCE(softirq_count() == 0);
3473
3474         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3475                 goto drop;
3476
3477         sband = local->hw.wiphy->bands[status->band];
3478         if (WARN_ON(!sband))
3479                 goto drop;
3480
3481         /*
3482          * If we're suspending, it is possible although not too likely
3483          * that we'd be receiving frames after having already partially
3484          * quiesced the stack. We can't process such frames then since
3485          * that might, for example, cause stations to be added or other
3486          * driver callbacks be invoked.
3487          */
3488         if (unlikely(local->quiescing || local->suspended))
3489                 goto drop;
3490
3491         /* We might be during a HW reconfig, prevent Rx for the same reason */
3492         if (unlikely(local->in_reconfig))
3493                 goto drop;
3494
3495         /*
3496          * The same happens when we're not even started,
3497          * but that's worth a warning.
3498          */
3499         if (WARN_ON(!local->started))
3500                 goto drop;
3501
3502         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3503                 /*
3504                  * Validate the rate, unless a PLCP error means that
3505                  * we probably can't have a valid rate here anyway.
3506                  */
3507
3508                 if (status->flag & RX_FLAG_HT) {
3509                         /*
3510                          * rate_idx is MCS index, which can be [0-76]
3511                          * as documented on:
3512                          *
3513                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3514                          *
3515                          * Anything else would be some sort of driver or
3516                          * hardware error. The driver should catch hardware
3517                          * errors.
3518                          */
3519                         if (WARN(status->rate_idx > 76,
3520                                  "Rate marked as an HT rate but passed "
3521                                  "status->rate_idx is not "
3522                                  "an MCS index [0-76]: %d (0x%02x)\n",
3523                                  status->rate_idx,
3524                                  status->rate_idx))
3525                                 goto drop;
3526                 } else if (status->flag & RX_FLAG_VHT) {
3527                         if (WARN_ONCE(status->rate_idx > 9 ||
3528                                       !status->vht_nss ||
3529                                       status->vht_nss > 8,
3530                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3531                                       status->rate_idx, status->vht_nss))
3532                                 goto drop;
3533                 } else {
3534                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3535                                 goto drop;
3536                         rate = &sband->bitrates[status->rate_idx];
3537                 }
3538         }
3539
3540         status->rx_flags = 0;
3541
3542         /*
3543          * key references and virtual interfaces are protected using RCU
3544          * and this requires that we are in a read-side RCU section during
3545          * receive processing
3546          */
3547         rcu_read_lock();
3548
3549         /*
3550          * Frames with failed FCS/PLCP checksum are not returned,
3551          * all other frames are returned without radiotap header
3552          * if it was previously present.
3553          * Also, frames with less than 16 bytes are dropped.
3554          */
3555         skb = ieee80211_rx_monitor(local, skb, rate);
3556         if (!skb) {
3557                 rcu_read_unlock();
3558                 return;
3559         }
3560
3561         ieee80211_tpt_led_trig_rx(local,
3562                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3563                         skb->len);
3564         __ieee80211_rx_handle_packet(hw, skb);
3565
3566         rcu_read_unlock();
3567
3568         return;
3569  drop:
3570         kfree_skb(skb);
3571 }
3572 EXPORT_SYMBOL(ieee80211_rx);
3573
3574 /* This is a version of the rx handler that can be called from hard irq
3575  * context. Post the skb on the queue and schedule the tasklet */
3576 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3577 {
3578         struct ieee80211_local *local = hw_to_local(hw);
3579
3580         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3581
3582         skb->pkt_type = IEEE80211_RX_MSG;
3583         skb_queue_tail(&local->skb_queue, skb);
3584         tasklet_schedule(&local->tasklet);
3585 }
3586 EXPORT_SYMBOL(ieee80211_rx_irqsafe);