6cbf1a7b3157467785581ad3814ef4f738c3391b
[linux-2.6.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       Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/jiffies.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rcupdate.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20
21 #include "ieee80211_i.h"
22 #include "driver-ops.h"
23 #include "led.h"
24 #include "mesh.h"
25 #include "wep.h"
26 #include "wpa.h"
27 #include "tkip.h"
28 #include "wme.h"
29
30 /*
31  * monitor mode reception
32  *
33  * This function cleans up the SKB, i.e. it removes all the stuff
34  * only useful for monitoring.
35  */
36 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
37                                            struct sk_buff *skb)
38 {
39         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
40                 if (likely(skb->len > FCS_LEN))
41                         skb_trim(skb, skb->len - FCS_LEN);
42                 else {
43                         /* driver bug */
44                         WARN_ON(1);
45                         dev_kfree_skb(skb);
46                         skb = NULL;
47                 }
48         }
49
50         return skb;
51 }
52
53 static inline int should_drop_frame(struct sk_buff *skb,
54                                     int present_fcs_len)
55 {
56         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
57         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
58
59         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
60                 return 1;
61         if (unlikely(skb->len < 16 + present_fcs_len))
62                 return 1;
63         if (ieee80211_is_ctl(hdr->frame_control) &&
64             !ieee80211_is_pspoll(hdr->frame_control) &&
65             !ieee80211_is_back_req(hdr->frame_control))
66                 return 1;
67         return 0;
68 }
69
70 static int
71 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
72                           struct ieee80211_rx_status *status)
73 {
74         int len;
75
76         /* always present fields */
77         len = sizeof(struct ieee80211_radiotap_header) + 9;
78
79         if (status->flag & RX_FLAG_TSFT)
80                 len += 8;
81         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
82                 len += 1;
83         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
84                 len += 1;
85
86         if (len & 1) /* padding for RX_FLAGS if necessary */
87                 len++;
88
89         return len;
90 }
91
92 /*
93  * ieee80211_add_rx_radiotap_header - add radiotap header
94  *
95  * add a radiotap header containing all the fields which the hardware provided.
96  */
97 static void
98 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
99                                  struct sk_buff *skb,
100                                  struct ieee80211_rate *rate,
101                                  int rtap_len)
102 {
103         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
104         struct ieee80211_radiotap_header *rthdr;
105         unsigned char *pos;
106         u16 rx_flags = 0;
107
108         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
109         memset(rthdr, 0, rtap_len);
110
111         /* radiotap header, set always present flags */
112         rthdr->it_present =
113                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
114                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
115                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
116                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
117         rthdr->it_len = cpu_to_le16(rtap_len);
118
119         pos = (unsigned char *)(rthdr+1);
120
121         /* the order of the following fields is important */
122
123         /* IEEE80211_RADIOTAP_TSFT */
124         if (status->flag & RX_FLAG_TSFT) {
125                 put_unaligned_le64(status->mactime, pos);
126                 rthdr->it_present |=
127                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
128                 pos += 8;
129         }
130
131         /* IEEE80211_RADIOTAP_FLAGS */
132         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
133                 *pos |= IEEE80211_RADIOTAP_F_FCS;
134         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
135                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
136         if (status->flag & RX_FLAG_SHORTPRE)
137                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
138         pos++;
139
140         /* IEEE80211_RADIOTAP_RATE */
141         if (status->flag & RX_FLAG_HT) {
142                 /*
143                  * TODO: add following information into radiotap header once
144                  * suitable fields are defined for it:
145                  * - MCS index (status->rate_idx)
146                  * - HT40 (status->flag & RX_FLAG_40MHZ)
147                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
148                  */
149                 *pos = 0;
150         } else {
151                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
152                 *pos = rate->bitrate / 5;
153         }
154         pos++;
155
156         /* IEEE80211_RADIOTAP_CHANNEL */
157         put_unaligned_le16(status->freq, pos);
158         pos += 2;
159         if (status->band == IEEE80211_BAND_5GHZ)
160                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
161                                    pos);
162         else if (status->flag & RX_FLAG_HT)
163                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
164                                    pos);
165         else if (rate->flags & IEEE80211_RATE_ERP_G)
166                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
167                                    pos);
168         else
169                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
170                                    pos);
171         pos += 2;
172
173         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
174         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
175                 *pos = status->signal;
176                 rthdr->it_present |=
177                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
178                 pos++;
179         }
180
181         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
182         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
183                 *pos = status->noise;
184                 rthdr->it_present |=
185                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
186                 pos++;
187         }
188
189         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
190
191         /* IEEE80211_RADIOTAP_ANTENNA */
192         *pos = status->antenna;
193         pos++;
194
195         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
196
197         /* IEEE80211_RADIOTAP_RX_FLAGS */
198         /* ensure 2 byte alignment for the 2 byte field as required */
199         if ((pos - (u8 *)rthdr) & 1)
200                 pos++;
201         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
202                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
203         put_unaligned_le16(rx_flags, pos);
204         pos += 2;
205 }
206
207 /*
208  * This function copies a received frame to all monitor interfaces and
209  * returns a cleaned-up SKB that no longer includes the FCS nor the
210  * radiotap header the driver might have added.
211  */
212 static struct sk_buff *
213 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
214                      struct ieee80211_rate *rate)
215 {
216         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
217         struct ieee80211_sub_if_data *sdata;
218         int needed_headroom = 0;
219         struct sk_buff *skb, *skb2;
220         struct net_device *prev_dev = NULL;
221         int present_fcs_len = 0;
222
223         /*
224          * First, we may need to make a copy of the skb because
225          *  (1) we need to modify it for radiotap (if not present), and
226          *  (2) the other RX handlers will modify the skb we got.
227          *
228          * We don't need to, of course, if we aren't going to return
229          * the SKB because it has a bad FCS/PLCP checksum.
230          */
231
232         /* room for the radiotap header based on driver features */
233         needed_headroom = ieee80211_rx_radiotap_len(local, status);
234
235         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
236                 present_fcs_len = FCS_LEN;
237
238         if (!local->monitors) {
239                 if (should_drop_frame(origskb, present_fcs_len)) {
240                         dev_kfree_skb(origskb);
241                         return NULL;
242                 }
243
244                 return remove_monitor_info(local, origskb);
245         }
246
247         if (should_drop_frame(origskb, present_fcs_len)) {
248                 /* only need to expand headroom if necessary */
249                 skb = origskb;
250                 origskb = NULL;
251
252                 /*
253                  * This shouldn't trigger often because most devices have an
254                  * RX header they pull before we get here, and that should
255                  * be big enough for our radiotap information. We should
256                  * probably export the length to drivers so that we can have
257                  * them allocate enough headroom to start with.
258                  */
259                 if (skb_headroom(skb) < needed_headroom &&
260                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
261                         dev_kfree_skb(skb);
262                         return NULL;
263                 }
264         } else {
265                 /*
266                  * Need to make a copy and possibly remove radiotap header
267                  * and FCS from the original.
268                  */
269                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
270
271                 origskb = remove_monitor_info(local, origskb);
272
273                 if (!skb)
274                         return origskb;
275         }
276
277         /* prepend radiotap information */
278         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
279
280         skb_reset_mac_header(skb);
281         skb->ip_summed = CHECKSUM_UNNECESSARY;
282         skb->pkt_type = PACKET_OTHERHOST;
283         skb->protocol = htons(ETH_P_802_2);
284
285         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
286                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
287                         continue;
288
289                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
290                         continue;
291
292                 if (!netif_running(sdata->dev))
293                         continue;
294
295                 if (prev_dev) {
296                         skb2 = skb_clone(skb, GFP_ATOMIC);
297                         if (skb2) {
298                                 skb2->dev = prev_dev;
299                                 netif_rx(skb2);
300                         }
301                 }
302
303                 prev_dev = sdata->dev;
304                 sdata->dev->stats.rx_packets++;
305                 sdata->dev->stats.rx_bytes += skb->len;
306         }
307
308         if (prev_dev) {
309                 skb->dev = prev_dev;
310                 netif_rx(skb);
311         } else
312                 dev_kfree_skb(skb);
313
314         return origskb;
315 }
316
317
318 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
319 {
320         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
321         int tid;
322
323         /* does the frame have a qos control field? */
324         if (ieee80211_is_data_qos(hdr->frame_control)) {
325                 u8 *qc = ieee80211_get_qos_ctl(hdr);
326                 /* frame has qos control */
327                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
328                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
329                         rx->flags |= IEEE80211_RX_AMSDU;
330                 else
331                         rx->flags &= ~IEEE80211_RX_AMSDU;
332         } else {
333                 /*
334                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
335                  *
336                  *      Sequence numbers for management frames, QoS data
337                  *      frames with a broadcast/multicast address in the
338                  *      Address 1 field, and all non-QoS data frames sent
339                  *      by QoS STAs are assigned using an additional single
340                  *      modulo-4096 counter, [...]
341                  *
342                  * We also use that counter for non-QoS STAs.
343                  */
344                 tid = NUM_RX_DATA_QUEUES - 1;
345         }
346
347         rx->queue = tid;
348         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
349          * For now, set skb->priority to 0 for other cases. */
350         rx->skb->priority = (tid > 7) ? 0 : tid;
351 }
352
353 /**
354  * DOC: Packet alignment
355  *
356  * Drivers always need to pass packets that are aligned to two-byte boundaries
357  * to the stack.
358  *
359  * Additionally, should, if possible, align the payload data in a way that
360  * guarantees that the contained IP header is aligned to a four-byte
361  * boundary. In the case of regular frames, this simply means aligning the
362  * payload to a four-byte boundary (because either the IP header is directly
363  * contained, or IV/RFC1042 headers that have a length divisible by four are
364  * in front of it).  If the payload data is not properly aligned and the
365  * architecture doesn't support efficient unaligned operations, mac80211
366  * will align the data.
367  *
368  * With A-MSDU frames, however, the payload data address must yield two modulo
369  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
370  * push the IP header further back to a multiple of four again. Thankfully, the
371  * specs were sane enough this time around to require padding each A-MSDU
372  * subframe to a length that is a multiple of four.
373  *
374  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
375  * the payload is not supported, the driver is required to move the 802.11
376  * header to be directly in front of the payload in that case.
377  */
378 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
379 {
380 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
381         WARN_ONCE((unsigned long)rx->skb->data & 1,
382                   "unaligned packet at 0x%p\n", rx->skb->data);
383 #endif
384 }
385
386
387 /* rx handlers */
388
389 static ieee80211_rx_result debug_noinline
390 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
391 {
392         struct ieee80211_local *local = rx->local;
393         struct sk_buff *skb = rx->skb;
394
395         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
396                 return ieee80211_scan_rx(rx->sdata, skb);
397
398         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
399                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
400                 /* drop all the other packets during a software scan anyway */
401                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
402                         dev_kfree_skb(skb);
403                 return RX_QUEUED;
404         }
405
406         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
407                 /* scanning finished during invoking of handlers */
408                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
409                 return RX_DROP_UNUSABLE;
410         }
411
412         return RX_CONTINUE;
413 }
414
415
416 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
417 {
418         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
419
420         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
421                 return 0;
422
423         return ieee80211_is_robust_mgmt_frame(hdr);
424 }
425
426
427 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
428 {
429         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
430
431         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
432                 return 0;
433
434         return ieee80211_is_robust_mgmt_frame(hdr);
435 }
436
437
438 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
439 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
440 {
441         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
442         struct ieee80211_mmie *mmie;
443
444         if (skb->len < 24 + sizeof(*mmie) ||
445             !is_multicast_ether_addr(hdr->da))
446                 return -1;
447
448         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
449                 return -1; /* not a robust management frame */
450
451         mmie = (struct ieee80211_mmie *)
452                 (skb->data + skb->len - sizeof(*mmie));
453         if (mmie->element_id != WLAN_EID_MMIE ||
454             mmie->length != sizeof(*mmie) - 2)
455                 return -1;
456
457         return le16_to_cpu(mmie->key_id);
458 }
459
460
461 static ieee80211_rx_result
462 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
463 {
464         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
465         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
466         char *dev_addr = rx->sdata->vif.addr;
467
468         if (ieee80211_is_data(hdr->frame_control)) {
469                 if (is_multicast_ether_addr(hdr->addr1)) {
470                         if (ieee80211_has_tods(hdr->frame_control) ||
471                                 !ieee80211_has_fromds(hdr->frame_control))
472                                 return RX_DROP_MONITOR;
473                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
474                                 return RX_DROP_MONITOR;
475                 } else {
476                         if (!ieee80211_has_a4(hdr->frame_control))
477                                 return RX_DROP_MONITOR;
478                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
479                                 return RX_DROP_MONITOR;
480                 }
481         }
482
483         /* If there is not an established peer link and this is not a peer link
484          * establisment frame, beacon or probe, drop the frame.
485          */
486
487         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
488                 struct ieee80211_mgmt *mgmt;
489
490                 if (!ieee80211_is_mgmt(hdr->frame_control))
491                         return RX_DROP_MONITOR;
492
493                 if (ieee80211_is_action(hdr->frame_control)) {
494                         mgmt = (struct ieee80211_mgmt *)hdr;
495                         if (mgmt->u.action.category != MESH_PLINK_CATEGORY)
496                                 return RX_DROP_MONITOR;
497                         return RX_CONTINUE;
498                 }
499
500                 if (ieee80211_is_probe_req(hdr->frame_control) ||
501                     ieee80211_is_probe_resp(hdr->frame_control) ||
502                     ieee80211_is_beacon(hdr->frame_control))
503                         return RX_CONTINUE;
504
505                 return RX_DROP_MONITOR;
506
507         }
508
509 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
510
511         if (ieee80211_is_data(hdr->frame_control) &&
512             is_multicast_ether_addr(hdr->addr1) &&
513             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
514                 return RX_DROP_MONITOR;
515 #undef msh_h_get
516
517         return RX_CONTINUE;
518 }
519
520 #define SEQ_MODULO 0x1000
521 #define SEQ_MASK   0xfff
522
523 static inline int seq_less(u16 sq1, u16 sq2)
524 {
525         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
526 }
527
528 static inline u16 seq_inc(u16 sq)
529 {
530         return (sq + 1) & SEQ_MASK;
531 }
532
533 static inline u16 seq_sub(u16 sq1, u16 sq2)
534 {
535         return (sq1 - sq2) & SEQ_MASK;
536 }
537
538
539 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
540                                             struct tid_ampdu_rx *tid_agg_rx,
541                                             int index,
542                                             struct sk_buff_head *frames)
543 {
544         struct ieee80211_supported_band *sband;
545         struct ieee80211_rate *rate = NULL;
546         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
547         struct ieee80211_rx_status *status;
548
549         if (!skb)
550                 goto no_frame;
551
552         status = IEEE80211_SKB_RXCB(skb);
553
554         /* release the reordered frames to stack */
555         sband = hw->wiphy->bands[status->band];
556         if (!(status->flag & RX_FLAG_HT))
557                 rate = &sband->bitrates[status->rate_idx];
558         tid_agg_rx->stored_mpdu_num--;
559         tid_agg_rx->reorder_buf[index] = NULL;
560         __skb_queue_tail(frames, skb);
561
562 no_frame:
563         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
564 }
565
566 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
567                                              struct tid_ampdu_rx *tid_agg_rx,
568                                              u16 head_seq_num,
569                                              struct sk_buff_head *frames)
570 {
571         int index;
572
573         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
574                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
575                                                         tid_agg_rx->buf_size;
576                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
577         }
578 }
579
580 /*
581  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
582  * the skb was added to the buffer longer than this time ago, the earlier
583  * frames that have not yet been received are assumed to be lost and the skb
584  * can be released for processing. This may also release other skb's from the
585  * reorder buffer if there are no additional gaps between the frames.
586  */
587 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
588
589 /*
590  * As this function belongs to the RX path it must be under
591  * rcu_read_lock protection. It returns false if the frame
592  * can be processed immediately, true if it was consumed.
593  */
594 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
595                                              struct tid_ampdu_rx *tid_agg_rx,
596                                              struct sk_buff *skb,
597                                              struct sk_buff_head *frames)
598 {
599         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
600         u16 sc = le16_to_cpu(hdr->seq_ctrl);
601         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
602         u16 head_seq_num, buf_size;
603         int index;
604
605         buf_size = tid_agg_rx->buf_size;
606         head_seq_num = tid_agg_rx->head_seq_num;
607
608         /* frame with out of date sequence number */
609         if (seq_less(mpdu_seq_num, head_seq_num)) {
610                 dev_kfree_skb(skb);
611                 return true;
612         }
613
614         /*
615          * If frame the sequence number exceeds our buffering window
616          * size release some previous frames to make room for this one.
617          */
618         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
619                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
620                 /* release stored frames up to new head to stack */
621                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
622                                                  frames);
623         }
624
625         /* Now the new frame is always in the range of the reordering buffer */
626
627         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
628
629         /* check if we already stored this frame */
630         if (tid_agg_rx->reorder_buf[index]) {
631                 dev_kfree_skb(skb);
632                 return true;
633         }
634
635         /*
636          * If the current MPDU is in the right order and nothing else
637          * is stored we can process it directly, no need to buffer it.
638          */
639         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
640             tid_agg_rx->stored_mpdu_num == 0) {
641                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
642                 return false;
643         }
644
645         /* put the frame in the reordering buffer */
646         tid_agg_rx->reorder_buf[index] = skb;
647         tid_agg_rx->reorder_time[index] = jiffies;
648         tid_agg_rx->stored_mpdu_num++;
649         /* release the buffer until next missing frame */
650         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
651                                                 tid_agg_rx->buf_size;
652         if (!tid_agg_rx->reorder_buf[index] &&
653             tid_agg_rx->stored_mpdu_num > 1) {
654                 /*
655                  * No buffers ready to be released, but check whether any
656                  * frames in the reorder buffer have timed out.
657                  */
658                 int j;
659                 int skipped = 1;
660                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
661                      j = (j + 1) % tid_agg_rx->buf_size) {
662                         if (!tid_agg_rx->reorder_buf[j]) {
663                                 skipped++;
664                                 continue;
665                         }
666                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
667                                         HT_RX_REORDER_BUF_TIMEOUT))
668                                 break;
669
670 #ifdef CONFIG_MAC80211_HT_DEBUG
671                         if (net_ratelimit())
672                                 printk(KERN_DEBUG "%s: release an RX reorder "
673                                        "frame due to timeout on earlier "
674                                        "frames\n",
675                                        wiphy_name(hw->wiphy));
676 #endif
677                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
678                                                         j, frames);
679
680                         /*
681                          * Increment the head seq# also for the skipped slots.
682                          */
683                         tid_agg_rx->head_seq_num =
684                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
685                         skipped = 0;
686                 }
687         } else while (tid_agg_rx->reorder_buf[index]) {
688                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
689                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
690                                                         tid_agg_rx->buf_size;
691         }
692
693         return true;
694 }
695
696 /*
697  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
698  * true if the MPDU was buffered, false if it should be processed.
699  */
700 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
701                                        struct sk_buff_head *frames)
702 {
703         struct sk_buff *skb = rx->skb;
704         struct ieee80211_local *local = rx->local;
705         struct ieee80211_hw *hw = &local->hw;
706         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
707         struct sta_info *sta = rx->sta;
708         struct tid_ampdu_rx *tid_agg_rx;
709         u16 sc;
710         int tid;
711
712         if (!ieee80211_is_data_qos(hdr->frame_control))
713                 goto dont_reorder;
714
715         /*
716          * filter the QoS data rx stream according to
717          * STA/TID and check if this STA/TID is on aggregation
718          */
719
720         if (!sta)
721                 goto dont_reorder;
722
723         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
724
725         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
726                 goto dont_reorder;
727
728         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
729
730         /* qos null data frames are excluded */
731         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
732                 goto dont_reorder;
733
734         /* new, potentially un-ordered, ampdu frame - process it */
735
736         /* reset session timer */
737         if (tid_agg_rx->timeout)
738                 mod_timer(&tid_agg_rx->session_timer,
739                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
740
741         /* if this mpdu is fragmented - terminate rx aggregation session */
742         sc = le16_to_cpu(hdr->seq_ctrl);
743         if (sc & IEEE80211_SCTL_FRAG) {
744                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
745                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
746                 dev_kfree_skb(skb);
747                 return;
748         }
749
750         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
751                 return;
752
753  dont_reorder:
754         __skb_queue_tail(frames, skb);
755 }
756
757 static ieee80211_rx_result debug_noinline
758 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
759 {
760         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
761
762         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
763         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
764                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
765                              rx->sta->last_seq_ctrl[rx->queue] ==
766                              hdr->seq_ctrl)) {
767                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
768                                 rx->local->dot11FrameDuplicateCount++;
769                                 rx->sta->num_duplicates++;
770                         }
771                         return RX_DROP_MONITOR;
772                 } else
773                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
774         }
775
776         if (unlikely(rx->skb->len < 16)) {
777                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
778                 return RX_DROP_MONITOR;
779         }
780
781         /* Drop disallowed frame classes based on STA auth/assoc state;
782          * IEEE 802.11, Chap 5.5.
783          *
784          * mac80211 filters only based on association state, i.e. it drops
785          * Class 3 frames from not associated stations. hostapd sends
786          * deauth/disassoc frames when needed. In addition, hostapd is
787          * responsible for filtering on both auth and assoc states.
788          */
789
790         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
791                 return ieee80211_rx_mesh_check(rx);
792
793         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
794                       ieee80211_is_pspoll(hdr->frame_control)) &&
795                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
796                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
797                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
798                      !ieee80211_has_tods(hdr->frame_control) &&
799                      ieee80211_is_data(hdr->frame_control)) ||
800                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
801                         /* Drop IBSS frames and frames for other hosts
802                          * silently. */
803                         return RX_DROP_MONITOR;
804                 }
805
806                 return RX_DROP_MONITOR;
807         }
808
809         return RX_CONTINUE;
810 }
811
812
813 static ieee80211_rx_result debug_noinline
814 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
815 {
816         struct sk_buff *skb = rx->skb;
817         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
818         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
819         int keyidx;
820         int hdrlen;
821         ieee80211_rx_result result = RX_DROP_UNUSABLE;
822         struct ieee80211_key *stakey = NULL;
823         int mmie_keyidx = -1;
824
825         /*
826          * Key selection 101
827          *
828          * There are four types of keys:
829          *  - GTK (group keys)
830          *  - IGTK (group keys for management frames)
831          *  - PTK (pairwise keys)
832          *  - STK (station-to-station pairwise keys)
833          *
834          * When selecting a key, we have to distinguish between multicast
835          * (including broadcast) and unicast frames, the latter can only
836          * use PTKs and STKs while the former always use GTKs and IGTKs.
837          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
838          * unicast frames can also use key indices like GTKs. Hence, if we
839          * don't have a PTK/STK we check the key index for a WEP key.
840          *
841          * Note that in a regular BSS, multicast frames are sent by the
842          * AP only, associated stations unicast the frame to the AP first
843          * which then multicasts it on their behalf.
844          *
845          * There is also a slight problem in IBSS mode: GTKs are negotiated
846          * with each station, that is something we don't currently handle.
847          * The spec seems to expect that one negotiates the same key with
848          * every station but there's no such requirement; VLANs could be
849          * possible.
850          */
851
852         /*
853          * No point in finding a key and decrypting if the frame is neither
854          * addressed to us nor a multicast frame.
855          */
856         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
857                 return RX_CONTINUE;
858
859         /* start without a key */
860         rx->key = NULL;
861
862         if (rx->sta)
863                 stakey = rcu_dereference(rx->sta->key);
864
865         if (!ieee80211_has_protected(hdr->frame_control))
866                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
867
868         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
869                 rx->key = stakey;
870                 /* Skip decryption if the frame is not protected. */
871                 if (!ieee80211_has_protected(hdr->frame_control))
872                         return RX_CONTINUE;
873         } else if (mmie_keyidx >= 0) {
874                 /* Broadcast/multicast robust management frame / BIP */
875                 if ((status->flag & RX_FLAG_DECRYPTED) &&
876                     (status->flag & RX_FLAG_IV_STRIPPED))
877                         return RX_CONTINUE;
878
879                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
880                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
881                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
882                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
883         } else if (!ieee80211_has_protected(hdr->frame_control)) {
884                 /*
885                  * The frame was not protected, so skip decryption. However, we
886                  * need to set rx->key if there is a key that could have been
887                  * used so that the frame may be dropped if encryption would
888                  * have been expected.
889                  */
890                 struct ieee80211_key *key = NULL;
891                 if (ieee80211_is_mgmt(hdr->frame_control) &&
892                     is_multicast_ether_addr(hdr->addr1) &&
893                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
894                         rx->key = key;
895                 else if ((key = rcu_dereference(rx->sdata->default_key)))
896                         rx->key = key;
897                 return RX_CONTINUE;
898         } else {
899                 /*
900                  * The device doesn't give us the IV so we won't be
901                  * able to look up the key. That's ok though, we
902                  * don't need to decrypt the frame, we just won't
903                  * be able to keep statistics accurate.
904                  * Except for key threshold notifications, should
905                  * we somehow allow the driver to tell us which key
906                  * the hardware used if this flag is set?
907                  */
908                 if ((status->flag & RX_FLAG_DECRYPTED) &&
909                     (status->flag & RX_FLAG_IV_STRIPPED))
910                         return RX_CONTINUE;
911
912                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
913
914                 if (rx->skb->len < 8 + hdrlen)
915                         return RX_DROP_UNUSABLE; /* TODO: count this? */
916
917                 /*
918                  * no need to call ieee80211_wep_get_keyidx,
919                  * it verifies a bunch of things we've done already
920                  */
921                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
922
923                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
924
925                 /*
926                  * RSNA-protected unicast frames should always be sent with
927                  * pairwise or station-to-station keys, but for WEP we allow
928                  * using a key index as well.
929                  */
930                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
931                     !is_multicast_ether_addr(hdr->addr1))
932                         rx->key = NULL;
933         }
934
935         if (rx->key) {
936                 rx->key->tx_rx_count++;
937                 /* TODO: add threshold stuff again */
938         } else {
939                 return RX_DROP_MONITOR;
940         }
941
942         /* Check for weak IVs if possible */
943         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
944             ieee80211_is_data(hdr->frame_control) &&
945             (!(status->flag & RX_FLAG_IV_STRIPPED) ||
946              !(status->flag & RX_FLAG_DECRYPTED)) &&
947             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
948                 rx->sta->wep_weak_iv_count++;
949
950         switch (rx->key->conf.alg) {
951         case ALG_WEP:
952                 result = ieee80211_crypto_wep_decrypt(rx);
953                 break;
954         case ALG_TKIP:
955                 result = ieee80211_crypto_tkip_decrypt(rx);
956                 break;
957         case ALG_CCMP:
958                 result = ieee80211_crypto_ccmp_decrypt(rx);
959                 break;
960         case ALG_AES_CMAC:
961                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
962                 break;
963         }
964
965         /* either the frame has been decrypted or will be dropped */
966         status->flag |= RX_FLAG_DECRYPTED;
967
968         return result;
969 }
970
971 static ieee80211_rx_result debug_noinline
972 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
973 {
974         struct ieee80211_local *local;
975         struct ieee80211_hdr *hdr;
976         struct sk_buff *skb;
977
978         local = rx->local;
979         skb = rx->skb;
980         hdr = (struct ieee80211_hdr *) skb->data;
981
982         if (!local->pspolling)
983                 return RX_CONTINUE;
984
985         if (!ieee80211_has_fromds(hdr->frame_control))
986                 /* this is not from AP */
987                 return RX_CONTINUE;
988
989         if (!ieee80211_is_data(hdr->frame_control))
990                 return RX_CONTINUE;
991
992         if (!ieee80211_has_moredata(hdr->frame_control)) {
993                 /* AP has no more frames buffered for us */
994                 local->pspolling = false;
995                 return RX_CONTINUE;
996         }
997
998         /* more data bit is set, let's request a new frame from the AP */
999         ieee80211_send_pspoll(local, rx->sdata);
1000
1001         return RX_CONTINUE;
1002 }
1003
1004 static void ap_sta_ps_start(struct sta_info *sta)
1005 {
1006         struct ieee80211_sub_if_data *sdata = sta->sdata;
1007         struct ieee80211_local *local = sdata->local;
1008
1009         atomic_inc(&sdata->bss->num_sta_ps);
1010         set_sta_flags(sta, WLAN_STA_PS_STA);
1011         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1012 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1013         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1014                sdata->name, sta->sta.addr, sta->sta.aid);
1015 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1016 }
1017
1018 static void ap_sta_ps_end(struct sta_info *sta)
1019 {
1020         struct ieee80211_sub_if_data *sdata = sta->sdata;
1021
1022         atomic_dec(&sdata->bss->num_sta_ps);
1023
1024         clear_sta_flags(sta, WLAN_STA_PS_STA);
1025
1026 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1027         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1028                sdata->name, sta->sta.addr, sta->sta.aid);
1029 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1030
1031         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1032 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1033                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1034                        sdata->name, sta->sta.addr, sta->sta.aid);
1035 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1036                 return;
1037         }
1038
1039         ieee80211_sta_ps_deliver_wakeup(sta);
1040 }
1041
1042 static ieee80211_rx_result debug_noinline
1043 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1044 {
1045         struct sta_info *sta = rx->sta;
1046         struct sk_buff *skb = rx->skb;
1047         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1048         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1049
1050         if (!sta)
1051                 return RX_CONTINUE;
1052
1053         /*
1054          * Update last_rx only for IBSS packets which are for the current
1055          * BSSID to avoid keeping the current IBSS network alive in cases
1056          * where other STAs start using different BSSID.
1057          */
1058         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1059                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1060                                                 NL80211_IFTYPE_ADHOC);
1061                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1062                         sta->last_rx = jiffies;
1063         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1064                 /*
1065                  * Mesh beacons will update last_rx when if they are found to
1066                  * match the current local configuration when processed.
1067                  */
1068                 sta->last_rx = jiffies;
1069         }
1070
1071         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1072                 return RX_CONTINUE;
1073
1074         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1075                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1076
1077         sta->rx_fragments++;
1078         sta->rx_bytes += rx->skb->len;
1079         sta->last_signal = status->signal;
1080         sta->last_noise = status->noise;
1081
1082         /*
1083          * Change STA power saving mode only at the end of a frame
1084          * exchange sequence.
1085          */
1086         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1087             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1088              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1089                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1090                         /*
1091                          * Ignore doze->wake transitions that are
1092                          * indicated by non-data frames, the standard
1093                          * is unclear here, but for example going to
1094                          * PS mode and then scanning would cause a
1095                          * doze->wake transition for the probe request,
1096                          * and that is clearly undesirable.
1097                          */
1098                         if (ieee80211_is_data(hdr->frame_control) &&
1099                             !ieee80211_has_pm(hdr->frame_control))
1100                                 ap_sta_ps_end(sta);
1101                 } else {
1102                         if (ieee80211_has_pm(hdr->frame_control))
1103                                 ap_sta_ps_start(sta);
1104                 }
1105         }
1106
1107         /*
1108          * Drop (qos-)data::nullfunc frames silently, since they
1109          * are used only to control station power saving mode.
1110          */
1111         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1112             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1113                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1114                 /*
1115                  * Update counter and free packet here to avoid
1116                  * counting this as a dropped packed.
1117                  */
1118                 sta->rx_packets++;
1119                 dev_kfree_skb(rx->skb);
1120                 return RX_QUEUED;
1121         }
1122
1123         return RX_CONTINUE;
1124 } /* ieee80211_rx_h_sta_process */
1125
1126 static inline struct ieee80211_fragment_entry *
1127 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1128                          unsigned int frag, unsigned int seq, int rx_queue,
1129                          struct sk_buff **skb)
1130 {
1131         struct ieee80211_fragment_entry *entry;
1132         int idx;
1133
1134         idx = sdata->fragment_next;
1135         entry = &sdata->fragments[sdata->fragment_next++];
1136         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1137                 sdata->fragment_next = 0;
1138
1139         if (!skb_queue_empty(&entry->skb_list)) {
1140 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1141                 struct ieee80211_hdr *hdr =
1142                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1143                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1144                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1145                        "addr1=%pM addr2=%pM\n",
1146                        sdata->name, idx,
1147                        jiffies - entry->first_frag_time, entry->seq,
1148                        entry->last_frag, hdr->addr1, hdr->addr2);
1149 #endif
1150                 __skb_queue_purge(&entry->skb_list);
1151         }
1152
1153         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1154         *skb = NULL;
1155         entry->first_frag_time = jiffies;
1156         entry->seq = seq;
1157         entry->rx_queue = rx_queue;
1158         entry->last_frag = frag;
1159         entry->ccmp = 0;
1160         entry->extra_len = 0;
1161
1162         return entry;
1163 }
1164
1165 static inline struct ieee80211_fragment_entry *
1166 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1167                           unsigned int frag, unsigned int seq,
1168                           int rx_queue, struct ieee80211_hdr *hdr)
1169 {
1170         struct ieee80211_fragment_entry *entry;
1171         int i, idx;
1172
1173         idx = sdata->fragment_next;
1174         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1175                 struct ieee80211_hdr *f_hdr;
1176
1177                 idx--;
1178                 if (idx < 0)
1179                         idx = IEEE80211_FRAGMENT_MAX - 1;
1180
1181                 entry = &sdata->fragments[idx];
1182                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1183                     entry->rx_queue != rx_queue ||
1184                     entry->last_frag + 1 != frag)
1185                         continue;
1186
1187                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1188
1189                 /*
1190                  * Check ftype and addresses are equal, else check next fragment
1191                  */
1192                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1193                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1194                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1195                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1196                         continue;
1197
1198                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1199                         __skb_queue_purge(&entry->skb_list);
1200                         continue;
1201                 }
1202                 return entry;
1203         }
1204
1205         return NULL;
1206 }
1207
1208 static ieee80211_rx_result debug_noinline
1209 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1210 {
1211         struct ieee80211_hdr *hdr;
1212         u16 sc;
1213         __le16 fc;
1214         unsigned int frag, seq;
1215         struct ieee80211_fragment_entry *entry;
1216         struct sk_buff *skb;
1217
1218         hdr = (struct ieee80211_hdr *)rx->skb->data;
1219         fc = hdr->frame_control;
1220         sc = le16_to_cpu(hdr->seq_ctrl);
1221         frag = sc & IEEE80211_SCTL_FRAG;
1222
1223         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1224                    (rx->skb)->len < 24 ||
1225                    is_multicast_ether_addr(hdr->addr1))) {
1226                 /* not fragmented */
1227                 goto out;
1228         }
1229         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1230
1231         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1232
1233         if (frag == 0) {
1234                 /* This is the first fragment of a new frame. */
1235                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1236                                                  rx->queue, &(rx->skb));
1237                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1238                     ieee80211_has_protected(fc)) {
1239                         /* Store CCMP PN so that we can verify that the next
1240                          * fragment has a sequential PN value. */
1241                         entry->ccmp = 1;
1242                         memcpy(entry->last_pn,
1243                                rx->key->u.ccmp.rx_pn[rx->queue],
1244                                CCMP_PN_LEN);
1245                 }
1246                 return RX_QUEUED;
1247         }
1248
1249         /* This is a fragment for a frame that should already be pending in
1250          * fragment cache. Add this fragment to the end of the pending entry.
1251          */
1252         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1253         if (!entry) {
1254                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1255                 return RX_DROP_MONITOR;
1256         }
1257
1258         /* Verify that MPDUs within one MSDU have sequential PN values.
1259          * (IEEE 802.11i, 8.3.3.4.5) */
1260         if (entry->ccmp) {
1261                 int i;
1262                 u8 pn[CCMP_PN_LEN], *rpn;
1263                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1264                         return RX_DROP_UNUSABLE;
1265                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1266                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1267                         pn[i]++;
1268                         if (pn[i])
1269                                 break;
1270                 }
1271                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1272                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1273                         return RX_DROP_UNUSABLE;
1274                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1275         }
1276
1277         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1278         __skb_queue_tail(&entry->skb_list, rx->skb);
1279         entry->last_frag = frag;
1280         entry->extra_len += rx->skb->len;
1281         if (ieee80211_has_morefrags(fc)) {
1282                 rx->skb = NULL;
1283                 return RX_QUEUED;
1284         }
1285
1286         rx->skb = __skb_dequeue(&entry->skb_list);
1287         if (skb_tailroom(rx->skb) < entry->extra_len) {
1288                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1289                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1290                                               GFP_ATOMIC))) {
1291                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1292                         __skb_queue_purge(&entry->skb_list);
1293                         return RX_DROP_UNUSABLE;
1294                 }
1295         }
1296         while ((skb = __skb_dequeue(&entry->skb_list))) {
1297                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1298                 dev_kfree_skb(skb);
1299         }
1300
1301         /* Complete frame has been reassembled - process it now */
1302         rx->flags |= IEEE80211_RX_FRAGMENTED;
1303
1304  out:
1305         if (rx->sta)
1306                 rx->sta->rx_packets++;
1307         if (is_multicast_ether_addr(hdr->addr1))
1308                 rx->local->dot11MulticastReceivedFrameCount++;
1309         else
1310                 ieee80211_led_rx(rx->local);
1311         return RX_CONTINUE;
1312 }
1313
1314 static ieee80211_rx_result debug_noinline
1315 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1316 {
1317         struct ieee80211_sub_if_data *sdata = rx->sdata;
1318         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1319
1320         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1321                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1322                 return RX_CONTINUE;
1323
1324         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1325             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1326                 return RX_DROP_UNUSABLE;
1327
1328         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1329                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1330         else
1331                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1332
1333         /* Free PS Poll skb here instead of returning RX_DROP that would
1334          * count as an dropped frame. */
1335         dev_kfree_skb(rx->skb);
1336
1337         return RX_QUEUED;
1338 }
1339
1340 static ieee80211_rx_result debug_noinline
1341 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1342 {
1343         u8 *data = rx->skb->data;
1344         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1345
1346         if (!ieee80211_is_data_qos(hdr->frame_control))
1347                 return RX_CONTINUE;
1348
1349         /* remove the qos control field, update frame type and meta-data */
1350         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1351                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1352         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1353         /* change frame type to non QOS */
1354         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1355
1356         return RX_CONTINUE;
1357 }
1358
1359 static int
1360 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1361 {
1362         if (unlikely(!rx->sta ||
1363             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1364                 return -EACCES;
1365
1366         return 0;
1367 }
1368
1369 static int
1370 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1371 {
1372         struct sk_buff *skb = rx->skb;
1373         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1374
1375         /*
1376          * Pass through unencrypted frames if the hardware has
1377          * decrypted them already.
1378          */
1379         if (status->flag & RX_FLAG_DECRYPTED)
1380                 return 0;
1381
1382         /* Drop unencrypted frames if key is set. */
1383         if (unlikely(!ieee80211_has_protected(fc) &&
1384                      !ieee80211_is_nullfunc(fc) &&
1385                      ieee80211_is_data(fc) &&
1386                      (rx->key || rx->sdata->drop_unencrypted)))
1387                 return -EACCES;
1388         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1389                 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1390                              rx->key))
1391                         return -EACCES;
1392                 /* BIP does not use Protected field, so need to check MMIE */
1393                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1394                              ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1395                              rx->key))
1396                         return -EACCES;
1397                 /*
1398                  * When using MFP, Action frames are not allowed prior to
1399                  * having configured keys.
1400                  */
1401                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1402                              ieee80211_is_robust_mgmt_frame(
1403                                      (struct ieee80211_hdr *) rx->skb->data)))
1404                         return -EACCES;
1405         }
1406
1407         return 0;
1408 }
1409
1410 static int
1411 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1412 {
1413         struct ieee80211_sub_if_data *sdata = rx->sdata;
1414         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1415
1416         if (ieee80211_has_a4(hdr->frame_control) &&
1417             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1418                 return -1;
1419
1420         if (is_multicast_ether_addr(hdr->addr1) &&
1421             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1422              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1423                 return -1;
1424
1425         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1426 }
1427
1428 /*
1429  * requires that rx->skb is a frame with ethernet header
1430  */
1431 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1432 {
1433         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1434                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1435         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1436
1437         /*
1438          * Allow EAPOL frames to us/the PAE group address regardless
1439          * of whether the frame was encrypted or not.
1440          */
1441         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1442             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1443              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1444                 return true;
1445
1446         if (ieee80211_802_1x_port_control(rx) ||
1447             ieee80211_drop_unencrypted(rx, fc))
1448                 return false;
1449
1450         return true;
1451 }
1452
1453 /*
1454  * requires that rx->skb is a frame with ethernet header
1455  */
1456 static void
1457 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1458 {
1459         struct ieee80211_sub_if_data *sdata = rx->sdata;
1460         struct net_device *dev = sdata->dev;
1461         struct sk_buff *skb, *xmit_skb;
1462         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1463         struct sta_info *dsta;
1464
1465         skb = rx->skb;
1466         xmit_skb = NULL;
1467
1468         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1469              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1470             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1471             (rx->flags & IEEE80211_RX_RA_MATCH) &&
1472             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1473                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1474                         /*
1475                          * send multicast frames both to higher layers in
1476                          * local net stack and back to the wireless medium
1477                          */
1478                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1479                         if (!xmit_skb && net_ratelimit())
1480                                 printk(KERN_DEBUG "%s: failed to clone "
1481                                        "multicast frame\n", dev->name);
1482                 } else {
1483                         dsta = sta_info_get(sdata, skb->data);
1484                         if (dsta) {
1485                                 /*
1486                                  * The destination station is associated to
1487                                  * this AP (in this VLAN), so send the frame
1488                                  * directly to it and do not pass it to local
1489                                  * net stack.
1490                                  */
1491                                 xmit_skb = skb;
1492                                 skb = NULL;
1493                         }
1494                 }
1495         }
1496
1497         if (skb) {
1498                 int align __maybe_unused;
1499
1500 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1501                 /*
1502                  * 'align' will only take the values 0 or 2 here
1503                  * since all frames are required to be aligned
1504                  * to 2-byte boundaries when being passed to
1505                  * mac80211. That also explains the __skb_push()
1506                  * below.
1507                  */
1508                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1509                 if (align) {
1510                         if (WARN_ON(skb_headroom(skb) < 3)) {
1511                                 dev_kfree_skb(skb);
1512                                 skb = NULL;
1513                         } else {
1514                                 u8 *data = skb->data;
1515                                 size_t len = skb_headlen(skb);
1516                                 skb->data -= align;
1517                                 memmove(skb->data, data, len);
1518                                 skb_set_tail_pointer(skb, len);
1519                         }
1520                 }
1521 #endif
1522
1523                 if (skb) {
1524                         /* deliver to local stack */
1525                         skb->protocol = eth_type_trans(skb, dev);
1526                         memset(skb->cb, 0, sizeof(skb->cb));
1527                         netif_rx(skb);
1528                 }
1529         }
1530
1531         if (xmit_skb) {
1532                 /* send to wireless media */
1533                 xmit_skb->protocol = htons(ETH_P_802_3);
1534                 skb_reset_network_header(xmit_skb);
1535                 skb_reset_mac_header(xmit_skb);
1536                 dev_queue_xmit(xmit_skb);
1537         }
1538 }
1539
1540 static ieee80211_rx_result debug_noinline
1541 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1542 {
1543         struct net_device *dev = rx->sdata->dev;
1544         struct sk_buff *skb = rx->skb;
1545         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1546         __le16 fc = hdr->frame_control;
1547         struct sk_buff_head frame_list;
1548
1549         if (unlikely(!ieee80211_is_data(fc)))
1550                 return RX_CONTINUE;
1551
1552         if (unlikely(!ieee80211_is_data_present(fc)))
1553                 return RX_DROP_MONITOR;
1554
1555         if (!(rx->flags & IEEE80211_RX_AMSDU))
1556                 return RX_CONTINUE;
1557
1558         if (ieee80211_has_a4(hdr->frame_control) &&
1559             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1560             !rx->sdata->u.vlan.sta)
1561                 return RX_DROP_UNUSABLE;
1562
1563         if (is_multicast_ether_addr(hdr->addr1) &&
1564             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1565               rx->sdata->u.vlan.sta) ||
1566              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1567               rx->sdata->u.mgd.use_4addr)))
1568                 return RX_DROP_UNUSABLE;
1569
1570         skb->dev = dev;
1571         __skb_queue_head_init(&frame_list);
1572
1573         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1574                                  rx->sdata->vif.type,
1575                                  rx->local->hw.extra_tx_headroom);
1576
1577         while (!skb_queue_empty(&frame_list)) {
1578                 rx->skb = __skb_dequeue(&frame_list);
1579
1580                 if (!ieee80211_frame_allowed(rx, fc)) {
1581                         dev_kfree_skb(rx->skb);
1582                         continue;
1583                 }
1584                 dev->stats.rx_packets++;
1585                 dev->stats.rx_bytes += rx->skb->len;
1586
1587                 ieee80211_deliver_skb(rx);
1588         }
1589
1590         return RX_QUEUED;
1591 }
1592
1593 #ifdef CONFIG_MAC80211_MESH
1594 static ieee80211_rx_result
1595 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1596 {
1597         struct ieee80211_hdr *hdr;
1598         struct ieee80211s_hdr *mesh_hdr;
1599         unsigned int hdrlen;
1600         struct sk_buff *skb = rx->skb, *fwd_skb;
1601         struct ieee80211_local *local = rx->local;
1602         struct ieee80211_sub_if_data *sdata = rx->sdata;
1603
1604         hdr = (struct ieee80211_hdr *) skb->data;
1605         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1606         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1607
1608         if (!ieee80211_is_data(hdr->frame_control))
1609                 return RX_CONTINUE;
1610
1611         if (!mesh_hdr->ttl)
1612                 /* illegal frame */
1613                 return RX_DROP_MONITOR;
1614
1615         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1616                 struct mesh_path *mppath;
1617                 char *proxied_addr;
1618                 char *mpp_addr;
1619
1620                 if (is_multicast_ether_addr(hdr->addr1)) {
1621                         mpp_addr = hdr->addr3;
1622                         proxied_addr = mesh_hdr->eaddr1;
1623                 } else {
1624                         mpp_addr = hdr->addr4;
1625                         proxied_addr = mesh_hdr->eaddr2;
1626                 }
1627
1628                 rcu_read_lock();
1629                 mppath = mpp_path_lookup(proxied_addr, sdata);
1630                 if (!mppath) {
1631                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1632                 } else {
1633                         spin_lock_bh(&mppath->state_lock);
1634                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1635                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1636                         spin_unlock_bh(&mppath->state_lock);
1637                 }
1638                 rcu_read_unlock();
1639         }
1640
1641         /* Frame has reached destination.  Don't forward */
1642         if (!is_multicast_ether_addr(hdr->addr1) &&
1643             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1644                 return RX_CONTINUE;
1645
1646         mesh_hdr->ttl--;
1647
1648         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1649                 if (!mesh_hdr->ttl)
1650                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1651                                                      dropped_frames_ttl);
1652                 else {
1653                         struct ieee80211_hdr *fwd_hdr;
1654                         struct ieee80211_tx_info *info;
1655
1656                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1657
1658                         if (!fwd_skb && net_ratelimit())
1659                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1660                                                    sdata->name);
1661
1662                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1663                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1664                         info = IEEE80211_SKB_CB(fwd_skb);
1665                         memset(info, 0, sizeof(*info));
1666                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1667                         info->control.vif = &rx->sdata->vif;
1668                         ieee80211_select_queue(local, fwd_skb);
1669                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1670                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1671                                                                 fwded_mcast);
1672                         else {
1673                                 int err;
1674                                 /*
1675                                  * Save TA to addr1 to send TA a path error if a
1676                                  * suitable next hop is not found
1677                                  */
1678                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1679                                                 ETH_ALEN);
1680                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1681                                 /* Failed to immediately resolve next hop:
1682                                  * fwded frame was dropped or will be added
1683                                  * later to the pending skb queue.  */
1684                                 if (err)
1685                                         return RX_DROP_MONITOR;
1686
1687                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1688                                                                 fwded_unicast);
1689                         }
1690                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1691                                                      fwded_frames);
1692                         ieee80211_add_pending_skb(local, fwd_skb);
1693                 }
1694         }
1695
1696         if (is_multicast_ether_addr(hdr->addr1) ||
1697             sdata->dev->flags & IFF_PROMISC)
1698                 return RX_CONTINUE;
1699         else
1700                 return RX_DROP_MONITOR;
1701 }
1702 #endif
1703
1704 static ieee80211_rx_result debug_noinline
1705 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1706 {
1707         struct ieee80211_sub_if_data *sdata = rx->sdata;
1708         struct net_device *dev = sdata->dev;
1709         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1710         __le16 fc = hdr->frame_control;
1711         int err;
1712
1713         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1714                 return RX_CONTINUE;
1715
1716         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1717                 return RX_DROP_MONITOR;
1718
1719         /*
1720          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1721          * that a 4-addr station can be detected and moved into a separate VLAN
1722          */
1723         if (ieee80211_has_a4(hdr->frame_control) &&
1724             sdata->vif.type == NL80211_IFTYPE_AP)
1725                 return RX_DROP_MONITOR;
1726
1727         err = __ieee80211_data_to_8023(rx);
1728         if (unlikely(err))
1729                 return RX_DROP_UNUSABLE;
1730
1731         if (!ieee80211_frame_allowed(rx, fc))
1732                 return RX_DROP_MONITOR;
1733
1734         rx->skb->dev = dev;
1735
1736         dev->stats.rx_packets++;
1737         dev->stats.rx_bytes += rx->skb->len;
1738
1739         ieee80211_deliver_skb(rx);
1740
1741         return RX_QUEUED;
1742 }
1743
1744 static ieee80211_rx_result debug_noinline
1745 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1746 {
1747         struct ieee80211_local *local = rx->local;
1748         struct ieee80211_hw *hw = &local->hw;
1749         struct sk_buff *skb = rx->skb;
1750         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1751         struct tid_ampdu_rx *tid_agg_rx;
1752         u16 start_seq_num;
1753         u16 tid;
1754
1755         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1756                 return RX_CONTINUE;
1757
1758         if (ieee80211_is_back_req(bar->frame_control)) {
1759                 if (!rx->sta)
1760                         return RX_DROP_MONITOR;
1761                 tid = le16_to_cpu(bar->control) >> 12;
1762                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1763                                         != HT_AGG_STATE_OPERATIONAL)
1764                         return RX_DROP_MONITOR;
1765                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1766
1767                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1768
1769                 /* reset session timer */
1770                 if (tid_agg_rx->timeout)
1771                         mod_timer(&tid_agg_rx->session_timer,
1772                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1773
1774                 /* release stored frames up to start of BAR */
1775                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1776                                                  frames);
1777                 kfree_skb(skb);
1778                 return RX_QUEUED;
1779         }
1780
1781         return RX_CONTINUE;
1782 }
1783
1784 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1785                                            struct ieee80211_mgmt *mgmt,
1786                                            size_t len)
1787 {
1788         struct ieee80211_local *local = sdata->local;
1789         struct sk_buff *skb;
1790         struct ieee80211_mgmt *resp;
1791
1792         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1793                 /* Not to own unicast address */
1794                 return;
1795         }
1796
1797         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1798             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1799                 /* Not from the current AP or not associated yet. */
1800                 return;
1801         }
1802
1803         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1804                 /* Too short SA Query request frame */
1805                 return;
1806         }
1807
1808         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1809         if (skb == NULL)
1810                 return;
1811
1812         skb_reserve(skb, local->hw.extra_tx_headroom);
1813         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1814         memset(resp, 0, 24);
1815         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1816         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1817         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1818         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1819                                           IEEE80211_STYPE_ACTION);
1820         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1821         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1822         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1823         memcpy(resp->u.action.u.sa_query.trans_id,
1824                mgmt->u.action.u.sa_query.trans_id,
1825                WLAN_SA_QUERY_TR_ID_LEN);
1826
1827         ieee80211_tx_skb(sdata, skb);
1828 }
1829
1830 static ieee80211_rx_result debug_noinline
1831 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1832 {
1833         struct ieee80211_local *local = rx->local;
1834         struct ieee80211_sub_if_data *sdata = rx->sdata;
1835         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1836         int len = rx->skb->len;
1837
1838         if (!ieee80211_is_action(mgmt->frame_control))
1839                 return RX_CONTINUE;
1840
1841         if (!rx->sta)
1842                 return RX_DROP_MONITOR;
1843
1844         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1845                 return RX_DROP_MONITOR;
1846
1847         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1848                 return RX_DROP_MONITOR;
1849
1850         /* all categories we currently handle have action_code */
1851         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1852                 return RX_DROP_MONITOR;
1853
1854         switch (mgmt->u.action.category) {
1855         case WLAN_CATEGORY_BACK:
1856                 /*
1857                  * The aggregation code is not prepared to handle
1858                  * anything but STA/AP due to the BSSID handling;
1859                  * IBSS could work in the code but isn't supported
1860                  * by drivers or the standard.
1861                  */
1862                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1863                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1864                     sdata->vif.type != NL80211_IFTYPE_AP)
1865                         return RX_DROP_MONITOR;
1866
1867                 switch (mgmt->u.action.u.addba_req.action_code) {
1868                 case WLAN_ACTION_ADDBA_REQ:
1869                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1870                                    sizeof(mgmt->u.action.u.addba_req)))
1871                                 return RX_DROP_MONITOR;
1872                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1873                         break;
1874                 case WLAN_ACTION_ADDBA_RESP:
1875                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1876                                    sizeof(mgmt->u.action.u.addba_resp)))
1877                                 return RX_DROP_MONITOR;
1878                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1879                         break;
1880                 case WLAN_ACTION_DELBA:
1881                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1882                                    sizeof(mgmt->u.action.u.delba)))
1883                                 return RX_DROP_MONITOR;
1884                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1885                         break;
1886                 }
1887                 break;
1888         case WLAN_CATEGORY_SPECTRUM_MGMT:
1889                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1890                         return RX_DROP_MONITOR;
1891
1892                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1893                         return RX_DROP_MONITOR;
1894
1895                 switch (mgmt->u.action.u.measurement.action_code) {
1896                 case WLAN_ACTION_SPCT_MSR_REQ:
1897                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1898                                    sizeof(mgmt->u.action.u.measurement)))
1899                                 return RX_DROP_MONITOR;
1900                         ieee80211_process_measurement_req(sdata, mgmt, len);
1901                         break;
1902                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1903                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1904                                    sizeof(mgmt->u.action.u.chan_switch)))
1905                                 return RX_DROP_MONITOR;
1906
1907                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1908                                 return RX_DROP_MONITOR;
1909
1910                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1911                                 return RX_DROP_MONITOR;
1912
1913                         return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1914                 }
1915                 break;
1916         case WLAN_CATEGORY_SA_QUERY:
1917                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1918                            sizeof(mgmt->u.action.u.sa_query)))
1919                         return RX_DROP_MONITOR;
1920                 switch (mgmt->u.action.u.sa_query.action) {
1921                 case WLAN_ACTION_SA_QUERY_REQUEST:
1922                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1923                                 return RX_DROP_MONITOR;
1924                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1925                         break;
1926                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1927                         /*
1928                          * SA Query response is currently only used in AP mode
1929                          * and it is processed in user space.
1930                          */
1931                         return RX_CONTINUE;
1932                 }
1933                 break;
1934         default:
1935                 return RX_CONTINUE;
1936         }
1937
1938         rx->sta->rx_packets++;
1939         dev_kfree_skb(rx->skb);
1940         return RX_QUEUED;
1941 }
1942
1943 static ieee80211_rx_result debug_noinline
1944 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1945 {
1946         struct ieee80211_sub_if_data *sdata = rx->sdata;
1947         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1948
1949         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1950                 return RX_DROP_MONITOR;
1951
1952         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1953                 return RX_DROP_MONITOR;
1954
1955         if (ieee80211_vif_is_mesh(&sdata->vif))
1956                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
1957
1958         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1959                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
1960
1961         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1962                 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1963
1964         return RX_DROP_MONITOR;
1965 }
1966
1967 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
1968                                             struct ieee80211_rx_data *rx)
1969 {
1970         int keyidx;
1971         unsigned int hdrlen;
1972
1973         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1974         if (rx->skb->len >= hdrlen + 4)
1975                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1976         else
1977                 keyidx = -1;
1978
1979         if (!rx->sta) {
1980                 /*
1981                  * Some hardware seem to generate incorrect Michael MIC
1982                  * reports; ignore them to avoid triggering countermeasures.
1983                  */
1984                 return;
1985         }
1986
1987         if (!ieee80211_has_protected(hdr->frame_control))
1988                 return;
1989
1990         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1991                 /*
1992                  * APs with pairwise keys should never receive Michael MIC
1993                  * errors for non-zero keyidx because these are reserved for
1994                  * group keys and only the AP is sending real multicast
1995                  * frames in the BSS.
1996                  */
1997                 return;
1998         }
1999
2000         if (!ieee80211_is_data(hdr->frame_control) &&
2001             !ieee80211_is_auth(hdr->frame_control))
2002                 return;
2003
2004         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2005                                         GFP_ATOMIC);
2006 }
2007
2008 /* TODO: use IEEE80211_RX_FRAGMENTED */
2009 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2010                                         struct ieee80211_rate *rate)
2011 {
2012         struct ieee80211_sub_if_data *sdata;
2013         struct ieee80211_local *local = rx->local;
2014         struct ieee80211_rtap_hdr {
2015                 struct ieee80211_radiotap_header hdr;
2016                 u8 flags;
2017                 u8 rate_or_pad;
2018                 __le16 chan_freq;
2019                 __le16 chan_flags;
2020         } __attribute__ ((packed)) *rthdr;
2021         struct sk_buff *skb = rx->skb, *skb2;
2022         struct net_device *prev_dev = NULL;
2023         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2024
2025         if (status->flag & RX_FLAG_INTERNAL_CMTR)
2026                 goto out_free_skb;
2027
2028         if (skb_headroom(skb) < sizeof(*rthdr) &&
2029             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2030                 goto out_free_skb;
2031
2032         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2033         memset(rthdr, 0, sizeof(*rthdr));
2034         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2035         rthdr->hdr.it_present =
2036                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2037                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2038
2039         if (rate) {
2040                 rthdr->rate_or_pad = rate->bitrate / 5;
2041                 rthdr->hdr.it_present |=
2042                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2043         }
2044         rthdr->chan_freq = cpu_to_le16(status->freq);
2045
2046         if (status->band == IEEE80211_BAND_5GHZ)
2047                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2048                                                 IEEE80211_CHAN_5GHZ);
2049         else
2050                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2051                                                 IEEE80211_CHAN_2GHZ);
2052
2053         skb_set_mac_header(skb, 0);
2054         skb->ip_summed = CHECKSUM_UNNECESSARY;
2055         skb->pkt_type = PACKET_OTHERHOST;
2056         skb->protocol = htons(ETH_P_802_2);
2057
2058         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2059                 if (!netif_running(sdata->dev))
2060                         continue;
2061
2062                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2063                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2064                         continue;
2065
2066                 if (prev_dev) {
2067                         skb2 = skb_clone(skb, GFP_ATOMIC);
2068                         if (skb2) {
2069                                 skb2->dev = prev_dev;
2070                                 netif_rx(skb2);
2071                         }
2072                 }
2073
2074                 prev_dev = sdata->dev;
2075                 sdata->dev->stats.rx_packets++;
2076                 sdata->dev->stats.rx_bytes += skb->len;
2077         }
2078
2079         if (prev_dev) {
2080                 skb->dev = prev_dev;
2081                 netif_rx(skb);
2082                 skb = NULL;
2083         } else
2084                 goto out_free_skb;
2085
2086         status->flag |= RX_FLAG_INTERNAL_CMTR;
2087         return;
2088
2089  out_free_skb:
2090         dev_kfree_skb(skb);
2091 }
2092
2093
2094 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2095                                          struct ieee80211_rx_data *rx,
2096                                          struct sk_buff *skb,
2097                                          struct ieee80211_rate *rate)
2098 {
2099         struct sk_buff_head reorder_release;
2100         ieee80211_rx_result res = RX_DROP_MONITOR;
2101
2102         __skb_queue_head_init(&reorder_release);
2103
2104         rx->skb = skb;
2105         rx->sdata = sdata;
2106
2107 #define CALL_RXH(rxh)                   \
2108         do {                            \
2109                 res = rxh(rx);          \
2110                 if (res != RX_CONTINUE) \
2111                         goto rxh_next;  \
2112         } while (0);
2113
2114         /*
2115          * NB: the rxh_next label works even if we jump
2116          *     to it from here because then the list will
2117          *     be empty, which is a trivial check
2118          */
2119         CALL_RXH(ieee80211_rx_h_passive_scan)
2120         CALL_RXH(ieee80211_rx_h_check)
2121
2122         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2123
2124         while ((skb = __skb_dequeue(&reorder_release))) {
2125                 /*
2126                  * all the other fields are valid across frames
2127                  * that belong to an aMPDU since they are on the
2128                  * same TID from the same station
2129                  */
2130                 rx->skb = skb;
2131
2132                 CALL_RXH(ieee80211_rx_h_decrypt)
2133                 CALL_RXH(ieee80211_rx_h_check_more_data)
2134                 CALL_RXH(ieee80211_rx_h_sta_process)
2135                 CALL_RXH(ieee80211_rx_h_defragment)
2136                 CALL_RXH(ieee80211_rx_h_ps_poll)
2137                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2138                 /* must be after MMIC verify so header is counted in MPDU mic */
2139                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2140                 CALL_RXH(ieee80211_rx_h_amsdu)
2141 #ifdef CONFIG_MAC80211_MESH
2142                 if (ieee80211_vif_is_mesh(&sdata->vif))
2143                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2144 #endif
2145                 CALL_RXH(ieee80211_rx_h_data)
2146
2147                 /* special treatment -- needs the queue */
2148                 res = ieee80211_rx_h_ctrl(rx, &reorder_release);
2149                 if (res != RX_CONTINUE)
2150                         goto rxh_next;
2151
2152                 CALL_RXH(ieee80211_rx_h_action)
2153                 CALL_RXH(ieee80211_rx_h_mgmt)
2154
2155 #undef CALL_RXH
2156
2157  rxh_next:
2158                 switch (res) {
2159                 case RX_DROP_MONITOR:
2160                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2161                         if (rx->sta)
2162                                 rx->sta->rx_dropped++;
2163                         /* fall through */
2164                 case RX_CONTINUE:
2165                         ieee80211_rx_cooked_monitor(rx, rate);
2166                         break;
2167                 case RX_DROP_UNUSABLE:
2168                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2169                         if (rx->sta)
2170                                 rx->sta->rx_dropped++;
2171                         dev_kfree_skb(rx->skb);
2172                         break;
2173                 case RX_QUEUED:
2174                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2175                         break;
2176                 }
2177         }
2178 }
2179
2180 /* main receive path */
2181
2182 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2183                                 struct ieee80211_rx_data *rx,
2184                                 struct ieee80211_hdr *hdr)
2185 {
2186         struct sk_buff *skb = rx->skb;
2187         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2188         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2189         int multicast = is_multicast_ether_addr(hdr->addr1);
2190
2191         switch (sdata->vif.type) {
2192         case NL80211_IFTYPE_STATION:
2193                 if (!bssid && !sdata->u.mgd.use_4addr)
2194                         return 0;
2195                 if (!multicast &&
2196                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2197                         if (!(sdata->dev->flags & IFF_PROMISC))
2198                                 return 0;
2199                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2200                 }
2201                 break;
2202         case NL80211_IFTYPE_ADHOC:
2203                 if (!bssid)
2204                         return 0;
2205                 if (ieee80211_is_beacon(hdr->frame_control)) {
2206                         return 1;
2207                 }
2208                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2209                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2210                                 return 0;
2211                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2212                 } else if (!multicast &&
2213                            compare_ether_addr(sdata->vif.addr,
2214                                               hdr->addr1) != 0) {
2215                         if (!(sdata->dev->flags & IFF_PROMISC))
2216                                 return 0;
2217                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2218                 } else if (!rx->sta) {
2219                         int rate_idx;
2220                         if (status->flag & RX_FLAG_HT)
2221                                 rate_idx = 0; /* TODO: HT rates */
2222                         else
2223                                 rate_idx = status->rate_idx;
2224                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2225                                 BIT(rate_idx));
2226                 }
2227                 break;
2228         case NL80211_IFTYPE_MESH_POINT:
2229                 if (!multicast &&
2230                     compare_ether_addr(sdata->vif.addr,
2231                                        hdr->addr1) != 0) {
2232                         if (!(sdata->dev->flags & IFF_PROMISC))
2233                                 return 0;
2234
2235                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2236                 }
2237                 break;
2238         case NL80211_IFTYPE_AP_VLAN:
2239         case NL80211_IFTYPE_AP:
2240                 if (!bssid) {
2241                         if (compare_ether_addr(sdata->vif.addr,
2242                                                hdr->addr1))
2243                                 return 0;
2244                 } else if (!ieee80211_bssid_match(bssid,
2245                                         sdata->vif.addr)) {
2246                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2247                                 return 0;
2248                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2249                 }
2250                 break;
2251         case NL80211_IFTYPE_WDS:
2252                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2253                         return 0;
2254                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2255                         return 0;
2256                 break;
2257         case NL80211_IFTYPE_MONITOR:
2258         case NL80211_IFTYPE_UNSPECIFIED:
2259         case __NL80211_IFTYPE_AFTER_LAST:
2260                 /* should never get here */
2261                 WARN_ON(1);
2262                 break;
2263         }
2264
2265         return 1;
2266 }
2267
2268 /*
2269  * This is the actual Rx frames handler. as it blongs to Rx path it must
2270  * be called with rcu_read_lock protection.
2271  */
2272 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2273                                          struct sk_buff *skb,
2274                                          struct ieee80211_rate *rate)
2275 {
2276         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2277         struct ieee80211_local *local = hw_to_local(hw);
2278         struct ieee80211_sub_if_data *sdata;
2279         struct ieee80211_hdr *hdr;
2280         struct ieee80211_rx_data rx;
2281         int prepares;
2282         struct ieee80211_sub_if_data *prev = NULL;
2283         struct sk_buff *skb_new;
2284         struct sta_info *sta, *tmp;
2285         bool found_sta = false;
2286
2287         hdr = (struct ieee80211_hdr *)skb->data;
2288         memset(&rx, 0, sizeof(rx));
2289         rx.skb = skb;
2290         rx.local = local;
2291
2292         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2293                 local->dot11ReceivedFragmentCount++;
2294
2295         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2296                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2297                 rx.flags |= IEEE80211_RX_IN_SCAN;
2298
2299         ieee80211_parse_qos(&rx);
2300         ieee80211_verify_alignment(&rx);
2301
2302         if (ieee80211_is_data(hdr->frame_control)) {
2303                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2304                         rx.sta = sta;
2305                         found_sta = true;
2306                         rx.sdata = sta->sdata;
2307
2308                         rx.flags |= IEEE80211_RX_RA_MATCH;
2309                         prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2310                         if (prepares) {
2311                                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2312                                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2313                                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2314                                 } else
2315                                         prev = rx.sdata;
2316                         }
2317                 }
2318         }
2319         if (!found_sta) {
2320                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2321                         if (!netif_running(sdata->dev))
2322                                 continue;
2323
2324                         if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2325                             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2326                                 continue;
2327
2328                         rx.sta = sta_info_get(sdata, hdr->addr2);
2329
2330                         rx.flags |= IEEE80211_RX_RA_MATCH;
2331                         prepares = prepare_for_handlers(sdata, &rx, hdr);
2332
2333                         if (!prepares)
2334                                 continue;
2335
2336                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2337                                 rx.sdata = sdata;
2338                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2339                                         ieee80211_rx_michael_mic_report(hdr,
2340                                                                         &rx);
2341                                 continue;
2342                         }
2343
2344                         /*
2345                          * frame is destined for this interface, but if it's
2346                          * not also for the previous one we handle that after
2347                          * the loop to avoid copying the SKB once too much
2348                          */
2349
2350                         if (!prev) {
2351                                 prev = sdata;
2352                                 continue;
2353                         }
2354
2355                         /*
2356                          * frame was destined for the previous interface
2357                          * so invoke RX handlers for it
2358                          */
2359
2360                         skb_new = skb_copy(skb, GFP_ATOMIC);
2361                         if (!skb_new) {
2362                                 if (net_ratelimit())
2363                                         printk(KERN_DEBUG "%s: failed to copy "
2364                                                "multicast frame for %s\n",
2365                                                wiphy_name(local->hw.wiphy),
2366                                                prev->name);
2367                                 continue;
2368                         }
2369                         ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
2370                         prev = sdata;
2371                 }
2372         }
2373         if (prev)
2374                 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate);
2375         else
2376                 dev_kfree_skb(skb);
2377 }
2378
2379 /*
2380  * This is the receive path handler. It is called by a low level driver when an
2381  * 802.11 MPDU is received from the hardware.
2382  */
2383 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2384 {
2385         struct ieee80211_local *local = hw_to_local(hw);
2386         struct ieee80211_rate *rate = NULL;
2387         struct ieee80211_supported_band *sband;
2388         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2389
2390         WARN_ON_ONCE(softirq_count() == 0);
2391
2392         if (WARN_ON(status->band < 0 ||
2393                     status->band >= IEEE80211_NUM_BANDS))
2394                 goto drop;
2395
2396         sband = local->hw.wiphy->bands[status->band];
2397         if (WARN_ON(!sband))
2398                 goto drop;
2399
2400         /*
2401          * If we're suspending, it is possible although not too likely
2402          * that we'd be receiving frames after having already partially
2403          * quiesced the stack. We can't process such frames then since
2404          * that might, for example, cause stations to be added or other
2405          * driver callbacks be invoked.
2406          */
2407         if (unlikely(local->quiescing || local->suspended))
2408                 goto drop;
2409
2410         /*
2411          * The same happens when we're not even started,
2412          * but that's worth a warning.
2413          */
2414         if (WARN_ON(!local->started))
2415                 goto drop;
2416
2417         if (status->flag & RX_FLAG_HT) {
2418                 /*
2419                  * rate_idx is MCS index, which can be [0-76] as documented on:
2420                  *
2421                  * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2422                  *
2423                  * Anything else would be some sort of driver or hardware error.
2424                  * The driver should catch hardware errors.
2425                  */
2426                 if (WARN((status->rate_idx < 0 ||
2427                          status->rate_idx > 76),
2428                          "Rate marked as an HT rate but passed "
2429                          "status->rate_idx is not "
2430                          "an MCS index [0-76]: %d (0x%02x)\n",
2431                          status->rate_idx,
2432                          status->rate_idx))
2433                         goto drop;
2434         } else {
2435                 if (WARN_ON(status->rate_idx < 0 ||
2436                             status->rate_idx >= sband->n_bitrates))
2437                         goto drop;
2438                 rate = &sband->bitrates[status->rate_idx];
2439         }
2440
2441         /*
2442          * key references and virtual interfaces are protected using RCU
2443          * and this requires that we are in a read-side RCU section during
2444          * receive processing
2445          */
2446         rcu_read_lock();
2447
2448         /*
2449          * Frames with failed FCS/PLCP checksum are not returned,
2450          * all other frames are returned without radiotap header
2451          * if it was previously present.
2452          * Also, frames with less than 16 bytes are dropped.
2453          */
2454         skb = ieee80211_rx_monitor(local, skb, rate);
2455         if (!skb) {
2456                 rcu_read_unlock();
2457                 return;
2458         }
2459
2460         __ieee80211_rx_handle_packet(hw, skb, rate);
2461
2462         rcu_read_unlock();
2463
2464         return;
2465  drop:
2466         kfree_skb(skb);
2467 }
2468 EXPORT_SYMBOL(ieee80211_rx);
2469
2470 /* This is a version of the rx handler that can be called from hard irq
2471  * context. Post the skb on the queue and schedule the tasklet */
2472 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2473 {
2474         struct ieee80211_local *local = hw_to_local(hw);
2475
2476         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2477
2478         skb->pkt_type = IEEE80211_RX_MSG;
2479         skb_queue_tail(&local->skb_queue, skb);
2480         tasklet_schedule(&local->tasklet);
2481 }
2482 EXPORT_SYMBOL(ieee80211_rx_irqsafe);