mac80211: decrease execution of the associated timer
[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 "led.h"
23 #include "mesh.h"
24 #include "wep.h"
25 #include "wpa.h"
26 #include "tkip.h"
27 #include "wme.h"
28
29 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
30                                            struct tid_ampdu_rx *tid_agg_rx,
31                                            struct sk_buff *skb,
32                                            u16 mpdu_seq_num,
33                                            int bar_req);
34 /*
35  * monitor mode reception
36  *
37  * This function cleans up the SKB, i.e. it removes all the stuff
38  * only useful for monitoring.
39  */
40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
41                                            struct sk_buff *skb,
42                                            int rtap_len)
43 {
44         skb_pull(skb, rtap_len);
45
46         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
47                 if (likely(skb->len > FCS_LEN))
48                         skb_trim(skb, skb->len - FCS_LEN);
49                 else {
50                         /* driver bug */
51                         WARN_ON(1);
52                         dev_kfree_skb(skb);
53                         skb = NULL;
54                 }
55         }
56
57         return skb;
58 }
59
60 static inline int should_drop_frame(struct ieee80211_rx_status *status,
61                                     struct sk_buff *skb,
62                                     int present_fcs_len,
63                                     int radiotap_len)
64 {
65         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
66
67         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
68                 return 1;
69         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
70                 return 1;
71         if (ieee80211_is_ctl(hdr->frame_control) &&
72             !ieee80211_is_pspoll(hdr->frame_control) &&
73             !ieee80211_is_back_req(hdr->frame_control))
74                 return 1;
75         return 0;
76 }
77
78 static int
79 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
80                           struct ieee80211_rx_status *status)
81 {
82         int len;
83
84         /* always present fields */
85         len = sizeof(struct ieee80211_radiotap_header) + 9;
86
87         if (status->flag & RX_FLAG_TSFT)
88                 len += 8;
89         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
90                 len += 1;
91         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
92                 len += 1;
93
94         if (len & 1) /* padding for RX_FLAGS if necessary */
95                 len++;
96
97         /* make sure radiotap starts at a naturally aligned address */
98         if (len % 8)
99                 len = roundup(len, 8);
100
101         return len;
102 }
103
104 /*
105  * ieee80211_add_rx_radiotap_header - add radiotap header
106  *
107  * add a radiotap header containing all the fields which the hardware provided.
108  */
109 static void
110 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
111                                  struct sk_buff *skb,
112                                  struct ieee80211_rx_status *status,
113                                  struct ieee80211_rate *rate,
114                                  int rtap_len)
115 {
116         struct ieee80211_radiotap_header *rthdr;
117         unsigned char *pos;
118
119         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
120         memset(rthdr, 0, rtap_len);
121
122         /* radiotap header, set always present flags */
123         rthdr->it_present =
124                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
125                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
126                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
127                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
128         rthdr->it_len = cpu_to_le16(rtap_len);
129
130         pos = (unsigned char *)(rthdr+1);
131
132         /* the order of the following fields is important */
133
134         /* IEEE80211_RADIOTAP_TSFT */
135         if (status->flag & RX_FLAG_TSFT) {
136                 *(__le64 *)pos = cpu_to_le64(status->mactime);
137                 rthdr->it_present |=
138                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
139                 pos += 8;
140         }
141
142         /* IEEE80211_RADIOTAP_FLAGS */
143         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
144                 *pos |= IEEE80211_RADIOTAP_F_FCS;
145         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
146                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
147         if (status->flag & RX_FLAG_SHORTPRE)
148                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
149         pos++;
150
151         /* IEEE80211_RADIOTAP_RATE */
152         if (status->flag & RX_FLAG_HT) {
153                 /*
154                  * TODO: add following information into radiotap header once
155                  * suitable fields are defined for it:
156                  * - MCS index (status->rate_idx)
157                  * - HT40 (status->flag & RX_FLAG_40MHZ)
158                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
159                  */
160                 *pos = 0;
161         } else {
162                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
163                 *pos = rate->bitrate / 5;
164         }
165         pos++;
166
167         /* IEEE80211_RADIOTAP_CHANNEL */
168         *(__le16 *)pos = cpu_to_le16(status->freq);
169         pos += 2;
170         if (status->band == IEEE80211_BAND_5GHZ)
171                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
172                                              IEEE80211_CHAN_5GHZ);
173         else if (rate->flags & IEEE80211_RATE_ERP_G)
174                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
175                                              IEEE80211_CHAN_2GHZ);
176         else
177                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
178                                              IEEE80211_CHAN_2GHZ);
179         pos += 2;
180
181         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
182         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
183                 *pos = status->signal;
184                 rthdr->it_present |=
185                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
186                 pos++;
187         }
188
189         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
190         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
191                 *pos = status->noise;
192                 rthdr->it_present |=
193                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
194                 pos++;
195         }
196
197         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
198
199         /* IEEE80211_RADIOTAP_ANTENNA */
200         *pos = status->antenna;
201         pos++;
202
203         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
204
205         /* IEEE80211_RADIOTAP_RX_FLAGS */
206         /* ensure 2 byte alignment for the 2 byte field as required */
207         if ((pos - (unsigned char *)rthdr) & 1)
208                 pos++;
209         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
210                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
211         pos += 2;
212 }
213
214 /*
215  * This function copies a received frame to all monitor interfaces and
216  * returns a cleaned-up SKB that no longer includes the FCS nor the
217  * radiotap header the driver might have added.
218  */
219 static struct sk_buff *
220 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
221                      struct ieee80211_rx_status *status,
222                      struct ieee80211_rate *rate)
223 {
224         struct ieee80211_sub_if_data *sdata;
225         int needed_headroom = 0;
226         struct sk_buff *skb, *skb2;
227         struct net_device *prev_dev = NULL;
228         int present_fcs_len = 0;
229         int rtap_len = 0;
230
231         /*
232          * First, we may need to make a copy of the skb because
233          *  (1) we need to modify it for radiotap (if not present), and
234          *  (2) the other RX handlers will modify the skb we got.
235          *
236          * We don't need to, of course, if we aren't going to return
237          * the SKB because it has a bad FCS/PLCP checksum.
238          */
239         if (status->flag & RX_FLAG_RADIOTAP)
240                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
241         else
242                 /* room for the radiotap header based on driver features */
243                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
244
245         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
246                 present_fcs_len = FCS_LEN;
247
248         if (!local->monitors) {
249                 if (should_drop_frame(status, origskb, present_fcs_len,
250                                       rtap_len)) {
251                         dev_kfree_skb(origskb);
252                         return NULL;
253                 }
254
255                 return remove_monitor_info(local, origskb, rtap_len);
256         }
257
258         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
259                 /* only need to expand headroom if necessary */
260                 skb = origskb;
261                 origskb = NULL;
262
263                 /*
264                  * This shouldn't trigger often because most devices have an
265                  * RX header they pull before we get here, and that should
266                  * be big enough for our radiotap information. We should
267                  * probably export the length to drivers so that we can have
268                  * them allocate enough headroom to start with.
269                  */
270                 if (skb_headroom(skb) < needed_headroom &&
271                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
272                         dev_kfree_skb(skb);
273                         return NULL;
274                 }
275         } else {
276                 /*
277                  * Need to make a copy and possibly remove radiotap header
278                  * and FCS from the original.
279                  */
280                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
281
282                 origskb = remove_monitor_info(local, origskb, rtap_len);
283
284                 if (!skb)
285                         return origskb;
286         }
287
288         /* if necessary, prepend radiotap information */
289         if (!(status->flag & RX_FLAG_RADIOTAP))
290                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
291                                                  needed_headroom);
292
293         skb_reset_mac_header(skb);
294         skb->ip_summed = CHECKSUM_UNNECESSARY;
295         skb->pkt_type = PACKET_OTHERHOST;
296         skb->protocol = htons(ETH_P_802_2);
297
298         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
299                 if (!netif_running(sdata->dev))
300                         continue;
301
302                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
303                         continue;
304
305                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
306                         continue;
307
308                 if (prev_dev) {
309                         skb2 = skb_clone(skb, GFP_ATOMIC);
310                         if (skb2) {
311                                 skb2->dev = prev_dev;
312                                 netif_rx(skb2);
313                         }
314                 }
315
316                 prev_dev = sdata->dev;
317                 sdata->dev->stats.rx_packets++;
318                 sdata->dev->stats.rx_bytes += skb->len;
319         }
320
321         if (prev_dev) {
322                 skb->dev = prev_dev;
323                 netif_rx(skb);
324         } else
325                 dev_kfree_skb(skb);
326
327         return origskb;
328 }
329
330
331 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
332 {
333         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
334         int tid;
335
336         /* does the frame have a qos control field? */
337         if (ieee80211_is_data_qos(hdr->frame_control)) {
338                 u8 *qc = ieee80211_get_qos_ctl(hdr);
339                 /* frame has qos control */
340                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
341                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
342                         rx->flags |= IEEE80211_RX_AMSDU;
343                 else
344                         rx->flags &= ~IEEE80211_RX_AMSDU;
345         } else {
346                 /*
347                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
348                  *
349                  *      Sequence numbers for management frames, QoS data
350                  *      frames with a broadcast/multicast address in the
351                  *      Address 1 field, and all non-QoS data frames sent
352                  *      by QoS STAs are assigned using an additional single
353                  *      modulo-4096 counter, [...]
354                  *
355                  * We also use that counter for non-QoS STAs.
356                  */
357                 tid = NUM_RX_DATA_QUEUES - 1;
358         }
359
360         rx->queue = tid;
361         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
362          * For now, set skb->priority to 0 for other cases. */
363         rx->skb->priority = (tid > 7) ? 0 : tid;
364 }
365
366 /**
367  * DOC: Packet alignment
368  *
369  * Drivers always need to pass packets that are aligned to two-byte boundaries
370  * to the stack.
371  *
372  * Additionally, should, if possible, align the payload data in a way that
373  * guarantees that the contained IP header is aligned to a four-byte
374  * boundary. In the case of regular frames, this simply means aligning the
375  * payload to a four-byte boundary (because either the IP header is directly
376  * contained, or IV/RFC1042 headers that have a length divisible by four are
377  * in front of it).
378  *
379  * With A-MSDU frames, however, the payload data address must yield two modulo
380  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
381  * push the IP header further back to a multiple of four again. Thankfully, the
382  * specs were sane enough this time around to require padding each A-MSDU
383  * subframe to a length that is a multiple of four.
384  *
385  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
386  * the payload is not supported, the driver is required to move the 802.11
387  * header to be directly in front of the payload in that case.
388  */
389 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
390 {
391         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
392         int hdrlen;
393
394 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
395         return;
396 #endif
397
398         if (WARN_ONCE((unsigned long)rx->skb->data & 1,
399                       "unaligned packet at 0x%p\n", rx->skb->data))
400                 return;
401
402         if (!ieee80211_is_data_present(hdr->frame_control))
403                 return;
404
405         hdrlen = ieee80211_hdrlen(hdr->frame_control);
406         if (rx->flags & IEEE80211_RX_AMSDU)
407                 hdrlen += ETH_HLEN;
408         WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
409                   "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
410 }
411
412
413 /* rx handlers */
414
415 static ieee80211_rx_result debug_noinline
416 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
417 {
418         struct ieee80211_local *local = rx->local;
419         struct sk_buff *skb = rx->skb;
420
421         if (unlikely(local->hw_scanning))
422                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
423
424         if (unlikely(local->sw_scanning)) {
425                 /* drop all the other packets during a software scan anyway */
426                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
427                     != RX_QUEUED)
428                         dev_kfree_skb(skb);
429                 return RX_QUEUED;
430         }
431
432         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
433                 /* scanning finished during invoking of handlers */
434                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
435                 return RX_DROP_UNUSABLE;
436         }
437
438         return RX_CONTINUE;
439 }
440
441
442 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
443 {
444         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
445
446         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
447                 return 0;
448
449         return ieee80211_is_robust_mgmt_frame(hdr);
450 }
451
452
453 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
454 {
455         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
456
457         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
458                 return 0;
459
460         return ieee80211_is_robust_mgmt_frame(hdr);
461 }
462
463
464 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
465 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
466 {
467         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
468         struct ieee80211_mmie *mmie;
469
470         if (skb->len < 24 + sizeof(*mmie) ||
471             !is_multicast_ether_addr(hdr->da))
472                 return -1;
473
474         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
475                 return -1; /* not a robust management frame */
476
477         mmie = (struct ieee80211_mmie *)
478                 (skb->data + skb->len - sizeof(*mmie));
479         if (mmie->element_id != WLAN_EID_MMIE ||
480             mmie->length != sizeof(*mmie) - 2)
481                 return -1;
482
483         return le16_to_cpu(mmie->key_id);
484 }
485
486
487 static ieee80211_rx_result
488 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
489 {
490         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
491         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
492
493         if (ieee80211_is_data(hdr->frame_control)) {
494                 if (!ieee80211_has_a4(hdr->frame_control))
495                         return RX_DROP_MONITOR;
496                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
497                         return RX_DROP_MONITOR;
498         }
499
500         /* If there is not an established peer link and this is not a peer link
501          * establisment frame, beacon or probe, drop the frame.
502          */
503
504         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
505                 struct ieee80211_mgmt *mgmt;
506
507                 if (!ieee80211_is_mgmt(hdr->frame_control))
508                         return RX_DROP_MONITOR;
509
510                 if (ieee80211_is_action(hdr->frame_control)) {
511                         mgmt = (struct ieee80211_mgmt *)hdr;
512                         if (mgmt->u.action.category != PLINK_CATEGORY)
513                                 return RX_DROP_MONITOR;
514                         return RX_CONTINUE;
515                 }
516
517                 if (ieee80211_is_probe_req(hdr->frame_control) ||
518                     ieee80211_is_probe_resp(hdr->frame_control) ||
519                     ieee80211_is_beacon(hdr->frame_control))
520                         return RX_CONTINUE;
521
522                 return RX_DROP_MONITOR;
523
524         }
525
526 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
527
528         if (ieee80211_is_data(hdr->frame_control) &&
529             is_multicast_ether_addr(hdr->addr1) &&
530             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
531                 return RX_DROP_MONITOR;
532 #undef msh_h_get
533
534         return RX_CONTINUE;
535 }
536
537
538 static ieee80211_rx_result debug_noinline
539 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
540 {
541         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
542
543         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
544         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
545                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
546                              rx->sta->last_seq_ctrl[rx->queue] ==
547                              hdr->seq_ctrl)) {
548                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
549                                 rx->local->dot11FrameDuplicateCount++;
550                                 rx->sta->num_duplicates++;
551                         }
552                         return RX_DROP_MONITOR;
553                 } else
554                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
555         }
556
557         if (unlikely(rx->skb->len < 16)) {
558                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
559                 return RX_DROP_MONITOR;
560         }
561
562         /* Drop disallowed frame classes based on STA auth/assoc state;
563          * IEEE 802.11, Chap 5.5.
564          *
565          * mac80211 filters only based on association state, i.e. it drops
566          * Class 3 frames from not associated stations. hostapd sends
567          * deauth/disassoc frames when needed. In addition, hostapd is
568          * responsible for filtering on both auth and assoc states.
569          */
570
571         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
572                 return ieee80211_rx_mesh_check(rx);
573
574         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
575                       ieee80211_is_pspoll(hdr->frame_control)) &&
576                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
577                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
578                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
579                      !ieee80211_has_tods(hdr->frame_control) &&
580                      ieee80211_is_data(hdr->frame_control)) ||
581                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
582                         /* Drop IBSS frames and frames for other hosts
583                          * silently. */
584                         return RX_DROP_MONITOR;
585                 }
586
587                 return RX_DROP_MONITOR;
588         }
589
590         return RX_CONTINUE;
591 }
592
593
594 static ieee80211_rx_result debug_noinline
595 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
596 {
597         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
598         int keyidx;
599         int hdrlen;
600         ieee80211_rx_result result = RX_DROP_UNUSABLE;
601         struct ieee80211_key *stakey = NULL;
602         int mmie_keyidx = -1;
603
604         /*
605          * Key selection 101
606          *
607          * There are four types of keys:
608          *  - GTK (group keys)
609          *  - IGTK (group keys for management frames)
610          *  - PTK (pairwise keys)
611          *  - STK (station-to-station pairwise keys)
612          *
613          * When selecting a key, we have to distinguish between multicast
614          * (including broadcast) and unicast frames, the latter can only
615          * use PTKs and STKs while the former always use GTKs and IGTKs.
616          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
617          * unicast frames can also use key indices like GTKs. Hence, if we
618          * don't have a PTK/STK we check the key index for a WEP key.
619          *
620          * Note that in a regular BSS, multicast frames are sent by the
621          * AP only, associated stations unicast the frame to the AP first
622          * which then multicasts it on their behalf.
623          *
624          * There is also a slight problem in IBSS mode: GTKs are negotiated
625          * with each station, that is something we don't currently handle.
626          * The spec seems to expect that one negotiates the same key with
627          * every station but there's no such requirement; VLANs could be
628          * possible.
629          */
630
631         if (!ieee80211_has_protected(hdr->frame_control)) {
632                 if (!ieee80211_is_mgmt(hdr->frame_control) ||
633                     rx->sta == NULL || !test_sta_flags(rx->sta, WLAN_STA_MFP))
634                         return RX_CONTINUE;
635                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
636                 if (mmie_keyidx < 0)
637                         return RX_CONTINUE;
638         }
639
640         /*
641          * No point in finding a key and decrypting if the frame is neither
642          * addressed to us nor a multicast frame.
643          */
644         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
645                 return RX_CONTINUE;
646
647         if (rx->sta)
648                 stakey = rcu_dereference(rx->sta->key);
649
650         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
651                 rx->key = stakey;
652         } else if (mmie_keyidx >= 0) {
653                 /* Broadcast/multicast robust management frame / BIP */
654                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
655                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
656                         return RX_CONTINUE;
657
658                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
659                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
660                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
661                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
662         } else {
663                 /*
664                  * The device doesn't give us the IV so we won't be
665                  * able to look up the key. That's ok though, we
666                  * don't need to decrypt the frame, we just won't
667                  * be able to keep statistics accurate.
668                  * Except for key threshold notifications, should
669                  * we somehow allow the driver to tell us which key
670                  * the hardware used if this flag is set?
671                  */
672                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
673                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
674                         return RX_CONTINUE;
675
676                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
677
678                 if (rx->skb->len < 8 + hdrlen)
679                         return RX_DROP_UNUSABLE; /* TODO: count this? */
680
681                 /*
682                  * no need to call ieee80211_wep_get_keyidx,
683                  * it verifies a bunch of things we've done already
684                  */
685                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
686
687                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
688
689                 /*
690                  * RSNA-protected unicast frames should always be sent with
691                  * pairwise or station-to-station keys, but for WEP we allow
692                  * using a key index as well.
693                  */
694                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
695                     !is_multicast_ether_addr(hdr->addr1))
696                         rx->key = NULL;
697         }
698
699         if (rx->key) {
700                 rx->key->tx_rx_count++;
701                 /* TODO: add threshold stuff again */
702         } else {
703                 return RX_DROP_MONITOR;
704         }
705
706         /* Check for weak IVs if possible */
707         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
708             ieee80211_is_data(hdr->frame_control) &&
709             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
710              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
711             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
712                 rx->sta->wep_weak_iv_count++;
713
714         switch (rx->key->conf.alg) {
715         case ALG_WEP:
716                 result = ieee80211_crypto_wep_decrypt(rx);
717                 break;
718         case ALG_TKIP:
719                 result = ieee80211_crypto_tkip_decrypt(rx);
720                 break;
721         case ALG_CCMP:
722                 result = ieee80211_crypto_ccmp_decrypt(rx);
723                 break;
724         case ALG_AES_CMAC:
725                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
726                 break;
727         }
728
729         /* either the frame has been decrypted or will be dropped */
730         rx->status->flag |= RX_FLAG_DECRYPTED;
731
732         return result;
733 }
734
735 static ieee80211_rx_result debug_noinline
736 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
737 {
738         struct ieee80211_local *local;
739         struct ieee80211_hdr *hdr;
740         struct sk_buff *skb;
741
742         local = rx->local;
743         skb = rx->skb;
744         hdr = (struct ieee80211_hdr *) skb->data;
745
746         if (!local->pspolling)
747                 return RX_CONTINUE;
748
749         if (!ieee80211_has_fromds(hdr->frame_control))
750                 /* this is not from AP */
751                 return RX_CONTINUE;
752
753         if (!ieee80211_is_data(hdr->frame_control))
754                 return RX_CONTINUE;
755
756         if (!ieee80211_has_moredata(hdr->frame_control)) {
757                 /* AP has no more frames buffered for us */
758                 local->pspolling = false;
759                 return RX_CONTINUE;
760         }
761
762         /* more data bit is set, let's request a new frame from the AP */
763         ieee80211_send_pspoll(local, rx->sdata);
764
765         return RX_CONTINUE;
766 }
767
768 static void ap_sta_ps_start(struct sta_info *sta)
769 {
770         struct ieee80211_sub_if_data *sdata = sta->sdata;
771         struct ieee80211_local *local = sdata->local;
772
773         atomic_inc(&sdata->bss->num_sta_ps);
774         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
775         if (local->ops->sta_notify)
776                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
777                                         STA_NOTIFY_SLEEP, &sta->sta);
778 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
779         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
780                sdata->dev->name, sta->sta.addr, sta->sta.aid);
781 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
782 }
783
784 static int ap_sta_ps_end(struct sta_info *sta)
785 {
786         struct ieee80211_sub_if_data *sdata = sta->sdata;
787         struct ieee80211_local *local = sdata->local;
788         struct sk_buff *skb;
789         int sent = 0;
790
791         atomic_dec(&sdata->bss->num_sta_ps);
792
793         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
794         if (local->ops->sta_notify)
795                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
796                                         STA_NOTIFY_AWAKE, &sta->sta);
797
798         if (!skb_queue_empty(&sta->ps_tx_buf))
799                 sta_info_clear_tim_bit(sta);
800
801 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
802         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
803                sdata->dev->name, sta->sta.addr, sta->sta.aid);
804 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
805
806         /* Send all buffered frames to the station */
807         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
808                 sent++;
809                 skb->requeue = 1;
810                 dev_queue_xmit(skb);
811         }
812         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
813                 local->total_ps_buffered--;
814                 sent++;
815 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
816                 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
817                        "since STA not sleeping anymore\n", sdata->dev->name,
818                        sta->sta.addr, sta->sta.aid);
819 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
820                 skb->requeue = 1;
821                 dev_queue_xmit(skb);
822         }
823
824         return sent;
825 }
826
827 static ieee80211_rx_result debug_noinline
828 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
829 {
830         struct sta_info *sta = rx->sta;
831         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
832
833         if (!sta)
834                 return RX_CONTINUE;
835
836         /* Update last_rx only for IBSS packets which are for the current
837          * BSSID to avoid keeping the current IBSS network alive in cases where
838          * other STAs are using different BSSID. */
839         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
840                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
841                                                 NL80211_IFTYPE_ADHOC);
842                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
843                         sta->last_rx = jiffies;
844         } else
845         if (!is_multicast_ether_addr(hdr->addr1) ||
846             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
847                 /* Update last_rx only for unicast frames in order to prevent
848                  * the Probe Request frames (the only broadcast frames from a
849                  * STA in infrastructure mode) from keeping a connection alive.
850                  * Mesh beacons will update last_rx when if they are found to
851                  * match the current local configuration when processed.
852                  */
853                 sta->last_rx = jiffies;
854         }
855
856         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
857                 return RX_CONTINUE;
858
859         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
860                 ieee80211_sta_rx_notify(rx->sdata, hdr);
861
862         sta->rx_fragments++;
863         sta->rx_bytes += rx->skb->len;
864         sta->last_signal = rx->status->signal;
865         sta->last_qual = rx->status->qual;
866         sta->last_noise = rx->status->noise;
867
868         /*
869          * Change STA power saving mode only at the end of a frame
870          * exchange sequence.
871          */
872         if (!ieee80211_has_morefrags(hdr->frame_control) &&
873             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
874              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
875                 if (test_sta_flags(sta, WLAN_STA_PS)) {
876                         /*
877                          * Ignore doze->wake transitions that are
878                          * indicated by non-data frames, the standard
879                          * is unclear here, but for example going to
880                          * PS mode and then scanning would cause a
881                          * doze->wake transition for the probe request,
882                          * and that is clearly undesirable.
883                          */
884                         if (ieee80211_is_data(hdr->frame_control) &&
885                             !ieee80211_has_pm(hdr->frame_control))
886                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
887                 } else {
888                         if (ieee80211_has_pm(hdr->frame_control))
889                                 ap_sta_ps_start(sta);
890                 }
891         }
892
893         /* Drop data::nullfunc frames silently, since they are used only to
894          * control station power saving mode. */
895         if (ieee80211_is_nullfunc(hdr->frame_control)) {
896                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
897                 /* Update counter and free packet here to avoid counting this
898                  * as a dropped packed. */
899                 sta->rx_packets++;
900                 dev_kfree_skb(rx->skb);
901                 return RX_QUEUED;
902         }
903
904         return RX_CONTINUE;
905 } /* ieee80211_rx_h_sta_process */
906
907 static inline struct ieee80211_fragment_entry *
908 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
909                          unsigned int frag, unsigned int seq, int rx_queue,
910                          struct sk_buff **skb)
911 {
912         struct ieee80211_fragment_entry *entry;
913         int idx;
914
915         idx = sdata->fragment_next;
916         entry = &sdata->fragments[sdata->fragment_next++];
917         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
918                 sdata->fragment_next = 0;
919
920         if (!skb_queue_empty(&entry->skb_list)) {
921 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
922                 struct ieee80211_hdr *hdr =
923                         (struct ieee80211_hdr *) entry->skb_list.next->data;
924                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
925                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
926                        "addr1=%pM addr2=%pM\n",
927                        sdata->dev->name, idx,
928                        jiffies - entry->first_frag_time, entry->seq,
929                        entry->last_frag, hdr->addr1, hdr->addr2);
930 #endif
931                 __skb_queue_purge(&entry->skb_list);
932         }
933
934         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
935         *skb = NULL;
936         entry->first_frag_time = jiffies;
937         entry->seq = seq;
938         entry->rx_queue = rx_queue;
939         entry->last_frag = frag;
940         entry->ccmp = 0;
941         entry->extra_len = 0;
942
943         return entry;
944 }
945
946 static inline struct ieee80211_fragment_entry *
947 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
948                           unsigned int frag, unsigned int seq,
949                           int rx_queue, struct ieee80211_hdr *hdr)
950 {
951         struct ieee80211_fragment_entry *entry;
952         int i, idx;
953
954         idx = sdata->fragment_next;
955         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
956                 struct ieee80211_hdr *f_hdr;
957
958                 idx--;
959                 if (idx < 0)
960                         idx = IEEE80211_FRAGMENT_MAX - 1;
961
962                 entry = &sdata->fragments[idx];
963                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
964                     entry->rx_queue != rx_queue ||
965                     entry->last_frag + 1 != frag)
966                         continue;
967
968                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
969
970                 /*
971                  * Check ftype and addresses are equal, else check next fragment
972                  */
973                 if (((hdr->frame_control ^ f_hdr->frame_control) &
974                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
975                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
976                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
977                         continue;
978
979                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
980                         __skb_queue_purge(&entry->skb_list);
981                         continue;
982                 }
983                 return entry;
984         }
985
986         return NULL;
987 }
988
989 static ieee80211_rx_result debug_noinline
990 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
991 {
992         struct ieee80211_hdr *hdr;
993         u16 sc;
994         __le16 fc;
995         unsigned int frag, seq;
996         struct ieee80211_fragment_entry *entry;
997         struct sk_buff *skb;
998
999         hdr = (struct ieee80211_hdr *)rx->skb->data;
1000         fc = hdr->frame_control;
1001         sc = le16_to_cpu(hdr->seq_ctrl);
1002         frag = sc & IEEE80211_SCTL_FRAG;
1003
1004         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1005                    (rx->skb)->len < 24 ||
1006                    is_multicast_ether_addr(hdr->addr1))) {
1007                 /* not fragmented */
1008                 goto out;
1009         }
1010         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1011
1012         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1013
1014         if (frag == 0) {
1015                 /* This is the first fragment of a new frame. */
1016                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1017                                                  rx->queue, &(rx->skb));
1018                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1019                     ieee80211_has_protected(fc)) {
1020                         /* Store CCMP PN so that we can verify that the next
1021                          * fragment has a sequential PN value. */
1022                         entry->ccmp = 1;
1023                         memcpy(entry->last_pn,
1024                                rx->key->u.ccmp.rx_pn[rx->queue],
1025                                CCMP_PN_LEN);
1026                 }
1027                 return RX_QUEUED;
1028         }
1029
1030         /* This is a fragment for a frame that should already be pending in
1031          * fragment cache. Add this fragment to the end of the pending entry.
1032          */
1033         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1034         if (!entry) {
1035                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1036                 return RX_DROP_MONITOR;
1037         }
1038
1039         /* Verify that MPDUs within one MSDU have sequential PN values.
1040          * (IEEE 802.11i, 8.3.3.4.5) */
1041         if (entry->ccmp) {
1042                 int i;
1043                 u8 pn[CCMP_PN_LEN], *rpn;
1044                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1045                         return RX_DROP_UNUSABLE;
1046                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1047                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1048                         pn[i]++;
1049                         if (pn[i])
1050                                 break;
1051                 }
1052                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1053                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1054                         return RX_DROP_UNUSABLE;
1055                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1056         }
1057
1058         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1059         __skb_queue_tail(&entry->skb_list, rx->skb);
1060         entry->last_frag = frag;
1061         entry->extra_len += rx->skb->len;
1062         if (ieee80211_has_morefrags(fc)) {
1063                 rx->skb = NULL;
1064                 return RX_QUEUED;
1065         }
1066
1067         rx->skb = __skb_dequeue(&entry->skb_list);
1068         if (skb_tailroom(rx->skb) < entry->extra_len) {
1069                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1070                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1071                                               GFP_ATOMIC))) {
1072                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1073                         __skb_queue_purge(&entry->skb_list);
1074                         return RX_DROP_UNUSABLE;
1075                 }
1076         }
1077         while ((skb = __skb_dequeue(&entry->skb_list))) {
1078                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1079                 dev_kfree_skb(skb);
1080         }
1081
1082         /* Complete frame has been reassembled - process it now */
1083         rx->flags |= IEEE80211_RX_FRAGMENTED;
1084
1085  out:
1086         if (rx->sta)
1087                 rx->sta->rx_packets++;
1088         if (is_multicast_ether_addr(hdr->addr1))
1089                 rx->local->dot11MulticastReceivedFrameCount++;
1090         else
1091                 ieee80211_led_rx(rx->local);
1092         return RX_CONTINUE;
1093 }
1094
1095 static ieee80211_rx_result debug_noinline
1096 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1097 {
1098         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1099         struct sk_buff *skb;
1100         int no_pending_pkts;
1101         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1102
1103         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1104                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1105                 return RX_CONTINUE;
1106
1107         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1108             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1109                 return RX_DROP_UNUSABLE;
1110
1111         skb = skb_dequeue(&rx->sta->tx_filtered);
1112         if (!skb) {
1113                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1114                 if (skb)
1115                         rx->local->total_ps_buffered--;
1116         }
1117         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1118                 skb_queue_empty(&rx->sta->ps_tx_buf);
1119
1120         if (skb) {
1121                 struct ieee80211_hdr *hdr =
1122                         (struct ieee80211_hdr *) skb->data;
1123
1124                 /*
1125                  * Tell TX path to send one frame even though the STA may
1126                  * still remain is PS mode after this frame exchange.
1127                  */
1128                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1129
1130 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1131                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1132                        rx->sta->sta.addr, rx->sta->sta.aid,
1133                        skb_queue_len(&rx->sta->ps_tx_buf));
1134 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1135
1136                 /* Use MoreData flag to indicate whether there are more
1137                  * buffered frames for this STA */
1138                 if (no_pending_pkts)
1139                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1140                 else
1141                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1142
1143                 dev_queue_xmit(skb);
1144
1145                 if (no_pending_pkts)
1146                         sta_info_clear_tim_bit(rx->sta);
1147 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1148         } else if (!rx->sent_ps_buffered) {
1149                 /*
1150                  * FIXME: This can be the result of a race condition between
1151                  *        us expiring a frame and the station polling for it.
1152                  *        Should we send it a null-func frame indicating we
1153                  *        have nothing buffered for it?
1154                  */
1155                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1156                        "though there are no buffered frames for it\n",
1157                        rx->dev->name, rx->sta->sta.addr);
1158 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1159         }
1160
1161         /* Free PS Poll skb here instead of returning RX_DROP that would
1162          * count as an dropped frame. */
1163         dev_kfree_skb(rx->skb);
1164
1165         return RX_QUEUED;
1166 }
1167
1168 static ieee80211_rx_result debug_noinline
1169 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1170 {
1171         u8 *data = rx->skb->data;
1172         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1173
1174         if (!ieee80211_is_data_qos(hdr->frame_control))
1175                 return RX_CONTINUE;
1176
1177         /* remove the qos control field, update frame type and meta-data */
1178         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1179                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1180         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1181         /* change frame type to non QOS */
1182         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1183
1184         return RX_CONTINUE;
1185 }
1186
1187 static int
1188 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1189 {
1190         if (unlikely(!rx->sta ||
1191             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1192                 return -EACCES;
1193
1194         return 0;
1195 }
1196
1197 static int
1198 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1199 {
1200         /*
1201          * Pass through unencrypted frames if the hardware has
1202          * decrypted them already.
1203          */
1204         if (rx->status->flag & RX_FLAG_DECRYPTED)
1205                 return 0;
1206
1207         /* Drop unencrypted frames if key is set. */
1208         if (unlikely(!ieee80211_has_protected(fc) &&
1209                      !ieee80211_is_nullfunc(fc) &&
1210                      (!ieee80211_is_mgmt(fc) ||
1211                       (ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1212                        rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP))) &&
1213                      (rx->key || rx->sdata->drop_unencrypted)))
1214                 return -EACCES;
1215         /* BIP does not use Protected field, so need to check MMIE */
1216         if (unlikely(rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP) &&
1217                      ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1218                      ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1219                      (rx->key || rx->sdata->drop_unencrypted)))
1220                 return -EACCES;
1221
1222         return 0;
1223 }
1224
1225 static int
1226 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1227 {
1228         struct net_device *dev = rx->dev;
1229         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1230         u16 hdrlen, ethertype;
1231         u8 *payload;
1232         u8 dst[ETH_ALEN];
1233         u8 src[ETH_ALEN] __aligned(2);
1234         struct sk_buff *skb = rx->skb;
1235         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1236
1237         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1238                 return -1;
1239
1240         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1241
1242         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1243          * header
1244          * IEEE 802.11 address fields:
1245          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1246          *   0     0   DA    SA    BSSID n/a
1247          *   0     1   DA    BSSID SA    n/a
1248          *   1     0   BSSID SA    DA    n/a
1249          *   1     1   RA    TA    DA    SA
1250          */
1251         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1252         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1253
1254         switch (hdr->frame_control &
1255                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1256         case cpu_to_le16(IEEE80211_FCTL_TODS):
1257                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1258                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1259                         return -1;
1260                 break;
1261         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1262                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1263                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1264                         return -1;
1265                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1266                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1267                                 (skb->data + hdrlen);
1268                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1269                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1270                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1271                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1272                         }
1273                 }
1274                 break;
1275         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1276                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1277                     (is_multicast_ether_addr(dst) &&
1278                      !compare_ether_addr(src, dev->dev_addr)))
1279                         return -1;
1280                 break;
1281         case cpu_to_le16(0):
1282                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1283                         return -1;
1284                 break;
1285         }
1286
1287         if (unlikely(skb->len - hdrlen < 8))
1288                 return -1;
1289
1290         payload = skb->data + hdrlen;
1291         ethertype = (payload[6] << 8) | payload[7];
1292
1293         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1294                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1295                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1296                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1297                  * replace EtherType */
1298                 skb_pull(skb, hdrlen + 6);
1299                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1300                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1301         } else {
1302                 struct ethhdr *ehdr;
1303                 __be16 len;
1304
1305                 skb_pull(skb, hdrlen);
1306                 len = htons(skb->len);
1307                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1308                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1309                 memcpy(ehdr->h_source, src, ETH_ALEN);
1310                 ehdr->h_proto = len;
1311         }
1312         return 0;
1313 }
1314
1315 /*
1316  * requires that rx->skb is a frame with ethernet header
1317  */
1318 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1319 {
1320         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1321                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1322         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1323
1324         /*
1325          * Allow EAPOL frames to us/the PAE group address regardless
1326          * of whether the frame was encrypted or not.
1327          */
1328         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1329             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1330              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1331                 return true;
1332
1333         if (ieee80211_802_1x_port_control(rx) ||
1334             ieee80211_drop_unencrypted(rx, fc))
1335                 return false;
1336
1337         return true;
1338 }
1339
1340 /*
1341  * requires that rx->skb is a frame with ethernet header
1342  */
1343 static void
1344 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1345 {
1346         struct net_device *dev = rx->dev;
1347         struct ieee80211_local *local = rx->local;
1348         struct sk_buff *skb, *xmit_skb;
1349         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1350         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1351         struct sta_info *dsta;
1352
1353         skb = rx->skb;
1354         xmit_skb = NULL;
1355
1356         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1357              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1358             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1359             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1360                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1361                         /*
1362                          * send multicast frames both to higher layers in
1363                          * local net stack and back to the wireless medium
1364                          */
1365                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1366                         if (!xmit_skb && net_ratelimit())
1367                                 printk(KERN_DEBUG "%s: failed to clone "
1368                                        "multicast frame\n", dev->name);
1369                 } else {
1370                         dsta = sta_info_get(local, skb->data);
1371                         if (dsta && dsta->sdata->dev == dev) {
1372                                 /*
1373                                  * The destination station is associated to
1374                                  * this AP (in this VLAN), so send the frame
1375                                  * directly to it and do not pass it to local
1376                                  * net stack.
1377                                  */
1378                                 xmit_skb = skb;
1379                                 skb = NULL;
1380                         }
1381                 }
1382         }
1383
1384         if (skb) {
1385                 int align __maybe_unused;
1386
1387 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1388                 /*
1389                  * 'align' will only take the values 0 or 2 here
1390                  * since all frames are required to be aligned
1391                  * to 2-byte boundaries when being passed to
1392                  * mac80211. That also explains the __skb_push()
1393                  * below.
1394                  */
1395                 align = (unsigned long)skb->data & 4;
1396                 if (align) {
1397                         if (WARN_ON(skb_headroom(skb) < 3)) {
1398                                 dev_kfree_skb(skb);
1399                                 skb = NULL;
1400                         } else {
1401                                 u8 *data = skb->data;
1402                                 size_t len = skb->len;
1403                                 u8 *new = __skb_push(skb, align);
1404                                 memmove(new, data, len);
1405                                 __skb_trim(skb, len);
1406                         }
1407                 }
1408 #endif
1409
1410                 if (skb) {
1411                         /* deliver to local stack */
1412                         skb->protocol = eth_type_trans(skb, dev);
1413                         memset(skb->cb, 0, sizeof(skb->cb));
1414                         netif_rx(skb);
1415                 }
1416         }
1417
1418         if (xmit_skb) {
1419                 /* send to wireless media */
1420                 xmit_skb->protocol = htons(ETH_P_802_3);
1421                 skb_reset_network_header(xmit_skb);
1422                 skb_reset_mac_header(xmit_skb);
1423                 dev_queue_xmit(xmit_skb);
1424         }
1425 }
1426
1427 static ieee80211_rx_result debug_noinline
1428 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1429 {
1430         struct net_device *dev = rx->dev;
1431         struct ieee80211_local *local = rx->local;
1432         u16 ethertype;
1433         u8 *payload;
1434         struct sk_buff *skb = rx->skb, *frame = NULL;
1435         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1436         __le16 fc = hdr->frame_control;
1437         const struct ethhdr *eth;
1438         int remaining, err;
1439         u8 dst[ETH_ALEN];
1440         u8 src[ETH_ALEN];
1441
1442         if (unlikely(!ieee80211_is_data(fc)))
1443                 return RX_CONTINUE;
1444
1445         if (unlikely(!ieee80211_is_data_present(fc)))
1446                 return RX_DROP_MONITOR;
1447
1448         if (!(rx->flags & IEEE80211_RX_AMSDU))
1449                 return RX_CONTINUE;
1450
1451         err = ieee80211_data_to_8023(rx);
1452         if (unlikely(err))
1453                 return RX_DROP_UNUSABLE;
1454
1455         skb->dev = dev;
1456
1457         dev->stats.rx_packets++;
1458         dev->stats.rx_bytes += skb->len;
1459
1460         /* skip the wrapping header */
1461         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1462         if (!eth)
1463                 return RX_DROP_UNUSABLE;
1464
1465         while (skb != frame) {
1466                 u8 padding;
1467                 __be16 len = eth->h_proto;
1468                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1469
1470                 remaining = skb->len;
1471                 memcpy(dst, eth->h_dest, ETH_ALEN);
1472                 memcpy(src, eth->h_source, ETH_ALEN);
1473
1474                 padding = ((4 - subframe_len) & 0x3);
1475                 /* the last MSDU has no padding */
1476                 if (subframe_len > remaining)
1477                         return RX_DROP_UNUSABLE;
1478
1479                 skb_pull(skb, sizeof(struct ethhdr));
1480                 /* if last subframe reuse skb */
1481                 if (remaining <= subframe_len + padding)
1482                         frame = skb;
1483                 else {
1484                         /*
1485                          * Allocate and reserve two bytes more for payload
1486                          * alignment since sizeof(struct ethhdr) is 14.
1487                          */
1488                         frame = dev_alloc_skb(
1489                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1490                                 subframe_len + 2);
1491
1492                         if (frame == NULL)
1493                                 return RX_DROP_UNUSABLE;
1494
1495                         skb_reserve(frame,
1496                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1497                                     sizeof(struct ethhdr) + 2);
1498                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1499                                 ntohs(len));
1500
1501                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1502                                                         padding);
1503                         if (!eth) {
1504                                 dev_kfree_skb(frame);
1505                                 return RX_DROP_UNUSABLE;
1506                         }
1507                 }
1508
1509                 skb_reset_network_header(frame);
1510                 frame->dev = dev;
1511                 frame->priority = skb->priority;
1512                 rx->skb = frame;
1513
1514                 payload = frame->data;
1515                 ethertype = (payload[6] << 8) | payload[7];
1516
1517                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1518                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1519                            compare_ether_addr(payload,
1520                                               bridge_tunnel_header) == 0)) {
1521                         /* remove RFC1042 or Bridge-Tunnel
1522                          * encapsulation and replace EtherType */
1523                         skb_pull(frame, 6);
1524                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1525                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1526                 } else {
1527                         memcpy(skb_push(frame, sizeof(__be16)),
1528                                &len, sizeof(__be16));
1529                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1530                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1531                 }
1532
1533                 if (!ieee80211_frame_allowed(rx, fc)) {
1534                         if (skb == frame) /* last frame */
1535                                 return RX_DROP_UNUSABLE;
1536                         dev_kfree_skb(frame);
1537                         continue;
1538                 }
1539
1540                 ieee80211_deliver_skb(rx);
1541         }
1542
1543         return RX_QUEUED;
1544 }
1545
1546 #ifdef CONFIG_MAC80211_MESH
1547 static ieee80211_rx_result
1548 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1549 {
1550         struct ieee80211_hdr *hdr;
1551         struct ieee80211s_hdr *mesh_hdr;
1552         unsigned int hdrlen;
1553         struct sk_buff *skb = rx->skb, *fwd_skb;
1554
1555         hdr = (struct ieee80211_hdr *) skb->data;
1556         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1557         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1558
1559         if (!ieee80211_is_data(hdr->frame_control))
1560                 return RX_CONTINUE;
1561
1562         if (!mesh_hdr->ttl)
1563                 /* illegal frame */
1564                 return RX_DROP_MONITOR;
1565
1566         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1567                 struct ieee80211_sub_if_data *sdata;
1568                 struct mesh_path *mppath;
1569
1570                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1571                 rcu_read_lock();
1572                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1573                 if (!mppath) {
1574                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1575                 } else {
1576                         spin_lock_bh(&mppath->state_lock);
1577                         mppath->exp_time = jiffies;
1578                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1579                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1580                         spin_unlock_bh(&mppath->state_lock);
1581                 }
1582                 rcu_read_unlock();
1583         }
1584
1585         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1586                 return RX_CONTINUE;
1587
1588         mesh_hdr->ttl--;
1589
1590         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1591                 if (!mesh_hdr->ttl)
1592                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1593                                                      dropped_frames_ttl);
1594                 else {
1595                         struct ieee80211_hdr *fwd_hdr;
1596                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1597
1598                         if (!fwd_skb && net_ratelimit())
1599                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1600                                                    rx->dev->name);
1601
1602                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1603                         /*
1604                          * Save TA to addr1 to send TA a path error if a
1605                          * suitable next hop is not found
1606                          */
1607                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1608                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1609                         fwd_skb->dev = rx->local->mdev;
1610                         fwd_skb->iif = rx->dev->ifindex;
1611                         dev_queue_xmit(fwd_skb);
1612                 }
1613         }
1614
1615         if (is_multicast_ether_addr(hdr->addr3) ||
1616             rx->dev->flags & IFF_PROMISC)
1617                 return RX_CONTINUE;
1618         else
1619                 return RX_DROP_MONITOR;
1620 }
1621 #endif
1622
1623 static ieee80211_rx_result debug_noinline
1624 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1625 {
1626         struct net_device *dev = rx->dev;
1627         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1628         __le16 fc = hdr->frame_control;
1629         int err;
1630
1631         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1632                 return RX_CONTINUE;
1633
1634         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1635                 return RX_DROP_MONITOR;
1636
1637         err = ieee80211_data_to_8023(rx);
1638         if (unlikely(err))
1639                 return RX_DROP_UNUSABLE;
1640
1641         if (!ieee80211_frame_allowed(rx, fc))
1642                 return RX_DROP_MONITOR;
1643
1644         rx->skb->dev = dev;
1645
1646         dev->stats.rx_packets++;
1647         dev->stats.rx_bytes += rx->skb->len;
1648
1649         ieee80211_deliver_skb(rx);
1650
1651         return RX_QUEUED;
1652 }
1653
1654 static ieee80211_rx_result debug_noinline
1655 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1656 {
1657         struct ieee80211_local *local = rx->local;
1658         struct ieee80211_hw *hw = &local->hw;
1659         struct sk_buff *skb = rx->skb;
1660         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1661         struct tid_ampdu_rx *tid_agg_rx;
1662         u16 start_seq_num;
1663         u16 tid;
1664
1665         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1666                 return RX_CONTINUE;
1667
1668         if (ieee80211_is_back_req(bar->frame_control)) {
1669                 if (!rx->sta)
1670                         return RX_CONTINUE;
1671                 tid = le16_to_cpu(bar->control) >> 12;
1672                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1673                                         != HT_AGG_STATE_OPERATIONAL)
1674                         return RX_CONTINUE;
1675                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1676
1677                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1678
1679                 /* reset session timer */
1680                 if (tid_agg_rx->timeout)
1681                         mod_timer(&tid_agg_rx->session_timer,
1682                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1683
1684                 /* manage reordering buffer according to requested */
1685                 /* sequence number */
1686                 rcu_read_lock();
1687                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1688                                                  start_seq_num, 1);
1689                 rcu_read_unlock();
1690                 return RX_DROP_UNUSABLE;
1691         }
1692
1693         return RX_CONTINUE;
1694 }
1695
1696 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1697                                            struct ieee80211_mgmt *mgmt,
1698                                            size_t len)
1699 {
1700         struct ieee80211_local *local = sdata->local;
1701         struct sk_buff *skb;
1702         struct ieee80211_mgmt *resp;
1703
1704         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1705                 /* Not to own unicast address */
1706                 return;
1707         }
1708
1709         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1710             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1711                 /* Not from the current AP. */
1712                 return;
1713         }
1714
1715         if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1716                 /* Association in progress; ignore SA Query */
1717                 return;
1718         }
1719
1720         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1721                 /* Too short SA Query request frame */
1722                 return;
1723         }
1724
1725         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1726         if (skb == NULL)
1727                 return;
1728
1729         skb_reserve(skb, local->hw.extra_tx_headroom);
1730         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1731         memset(resp, 0, 24);
1732         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1733         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1734         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1735         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1736                                           IEEE80211_STYPE_ACTION);
1737         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1738         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1739         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1740         memcpy(resp->u.action.u.sa_query.trans_id,
1741                mgmt->u.action.u.sa_query.trans_id,
1742                WLAN_SA_QUERY_TR_ID_LEN);
1743
1744         ieee80211_tx_skb(sdata, skb, 1);
1745 }
1746
1747 static ieee80211_rx_result debug_noinline
1748 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1749 {
1750         struct ieee80211_local *local = rx->local;
1751         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1752         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1753         struct ieee80211_bss *bss;
1754         int len = rx->skb->len;
1755
1756         if (!ieee80211_is_action(mgmt->frame_control))
1757                 return RX_CONTINUE;
1758
1759         if (!rx->sta)
1760                 return RX_DROP_MONITOR;
1761
1762         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1763                 return RX_DROP_MONITOR;
1764
1765         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1766                 return RX_DROP_MONITOR;
1767
1768         /* all categories we currently handle have action_code */
1769         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1770                 return RX_DROP_MONITOR;
1771
1772         switch (mgmt->u.action.category) {
1773         case WLAN_CATEGORY_BACK:
1774                 /*
1775                  * The aggregation code is not prepared to handle
1776                  * anything but STA/AP due to the BSSID handling;
1777                  * IBSS could work in the code but isn't supported
1778                  * by drivers or the standard.
1779                  */
1780                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1781                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1782                     sdata->vif.type != NL80211_IFTYPE_AP)
1783                         return RX_DROP_MONITOR;
1784
1785                 switch (mgmt->u.action.u.addba_req.action_code) {
1786                 case WLAN_ACTION_ADDBA_REQ:
1787                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1788                                    sizeof(mgmt->u.action.u.addba_req)))
1789                                 return RX_DROP_MONITOR;
1790                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1791                         break;
1792                 case WLAN_ACTION_ADDBA_RESP:
1793                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1794                                    sizeof(mgmt->u.action.u.addba_resp)))
1795                                 return RX_DROP_MONITOR;
1796                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1797                         break;
1798                 case WLAN_ACTION_DELBA:
1799                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1800                                    sizeof(mgmt->u.action.u.delba)))
1801                                 return RX_DROP_MONITOR;
1802                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1803                         break;
1804                 }
1805                 break;
1806         case WLAN_CATEGORY_SPECTRUM_MGMT:
1807                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1808                         return RX_DROP_MONITOR;
1809
1810                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1811                         return RX_DROP_MONITOR;
1812
1813                 switch (mgmt->u.action.u.measurement.action_code) {
1814                 case WLAN_ACTION_SPCT_MSR_REQ:
1815                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1816                                    sizeof(mgmt->u.action.u.measurement)))
1817                                 return RX_DROP_MONITOR;
1818                         ieee80211_process_measurement_req(sdata, mgmt, len);
1819                         break;
1820                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1821                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1822                                    sizeof(mgmt->u.action.u.chan_switch)))
1823                                 return RX_DROP_MONITOR;
1824
1825                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1826                                 return RX_DROP_MONITOR;
1827
1828                         bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1829                                            local->hw.conf.channel->center_freq,
1830                                            sdata->u.mgd.ssid,
1831                                            sdata->u.mgd.ssid_len);
1832                         if (!bss)
1833                                 return RX_DROP_MONITOR;
1834
1835                         ieee80211_process_chanswitch(sdata,
1836                                      &mgmt->u.action.u.chan_switch.sw_elem, bss);
1837                         ieee80211_rx_bss_put(local, bss);
1838                         break;
1839                 }
1840                 break;
1841         case WLAN_CATEGORY_SA_QUERY:
1842                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1843                            sizeof(mgmt->u.action.u.sa_query)))
1844                         return RX_DROP_MONITOR;
1845                 switch (mgmt->u.action.u.sa_query.action) {
1846                 case WLAN_ACTION_SA_QUERY_REQUEST:
1847                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1848                                 return RX_DROP_MONITOR;
1849                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1850                         break;
1851                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1852                         /*
1853                          * SA Query response is currently only used in AP mode
1854                          * and it is processed in user space.
1855                          */
1856                         return RX_CONTINUE;
1857                 }
1858                 break;
1859         default:
1860                 return RX_CONTINUE;
1861         }
1862
1863         rx->sta->rx_packets++;
1864         dev_kfree_skb(rx->skb);
1865         return RX_QUEUED;
1866 }
1867
1868 static ieee80211_rx_result debug_noinline
1869 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1870 {
1871         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1872         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1873
1874         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1875                 return RX_DROP_MONITOR;
1876
1877         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1878                 return RX_DROP_MONITOR;
1879
1880         if (ieee80211_vif_is_mesh(&sdata->vif))
1881                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1882
1883         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1884                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1885
1886         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1887                 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1888
1889         return RX_DROP_MONITOR;
1890 }
1891
1892 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1893                                             struct ieee80211_hdr *hdr,
1894                                             struct ieee80211_rx_data *rx)
1895 {
1896         int keyidx;
1897         unsigned int hdrlen;
1898
1899         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1900         if (rx->skb->len >= hdrlen + 4)
1901                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1902         else
1903                 keyidx = -1;
1904
1905         if (!rx->sta) {
1906                 /*
1907                  * Some hardware seem to generate incorrect Michael MIC
1908                  * reports; ignore them to avoid triggering countermeasures.
1909                  */
1910                 goto ignore;
1911         }
1912
1913         if (!ieee80211_has_protected(hdr->frame_control))
1914                 goto ignore;
1915
1916         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1917                 /*
1918                  * APs with pairwise keys should never receive Michael MIC
1919                  * errors for non-zero keyidx because these are reserved for
1920                  * group keys and only the AP is sending real multicast
1921                  * frames in the BSS.
1922                  */
1923                 goto ignore;
1924         }
1925
1926         if (!ieee80211_is_data(hdr->frame_control) &&
1927             !ieee80211_is_auth(hdr->frame_control))
1928                 goto ignore;
1929
1930         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1931  ignore:
1932         dev_kfree_skb(rx->skb);
1933         rx->skb = NULL;
1934 }
1935
1936 /* TODO: use IEEE80211_RX_FRAGMENTED */
1937 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1938 {
1939         struct ieee80211_sub_if_data *sdata;
1940         struct ieee80211_local *local = rx->local;
1941         struct ieee80211_rtap_hdr {
1942                 struct ieee80211_radiotap_header hdr;
1943                 u8 flags;
1944                 u8 rate;
1945                 __le16 chan_freq;
1946                 __le16 chan_flags;
1947         } __attribute__ ((packed)) *rthdr;
1948         struct sk_buff *skb = rx->skb, *skb2;
1949         struct net_device *prev_dev = NULL;
1950         struct ieee80211_rx_status *status = rx->status;
1951
1952         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1953                 goto out_free_skb;
1954
1955         if (skb_headroom(skb) < sizeof(*rthdr) &&
1956             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1957                 goto out_free_skb;
1958
1959         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1960         memset(rthdr, 0, sizeof(*rthdr));
1961         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1962         rthdr->hdr.it_present =
1963                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1964                             (1 << IEEE80211_RADIOTAP_RATE) |
1965                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1966
1967         rthdr->rate = rx->rate->bitrate / 5;
1968         rthdr->chan_freq = cpu_to_le16(status->freq);
1969
1970         if (status->band == IEEE80211_BAND_5GHZ)
1971                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1972                                                 IEEE80211_CHAN_5GHZ);
1973         else
1974                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1975                                                 IEEE80211_CHAN_2GHZ);
1976
1977         skb_set_mac_header(skb, 0);
1978         skb->ip_summed = CHECKSUM_UNNECESSARY;
1979         skb->pkt_type = PACKET_OTHERHOST;
1980         skb->protocol = htons(ETH_P_802_2);
1981
1982         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1983                 if (!netif_running(sdata->dev))
1984                         continue;
1985
1986                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1987                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1988                         continue;
1989
1990                 if (prev_dev) {
1991                         skb2 = skb_clone(skb, GFP_ATOMIC);
1992                         if (skb2) {
1993                                 skb2->dev = prev_dev;
1994                                 netif_rx(skb2);
1995                         }
1996                 }
1997
1998                 prev_dev = sdata->dev;
1999                 sdata->dev->stats.rx_packets++;
2000                 sdata->dev->stats.rx_bytes += skb->len;
2001         }
2002
2003         if (prev_dev) {
2004                 skb->dev = prev_dev;
2005                 netif_rx(skb);
2006                 skb = NULL;
2007         } else
2008                 goto out_free_skb;
2009
2010         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2011         return;
2012
2013  out_free_skb:
2014         dev_kfree_skb(skb);
2015 }
2016
2017
2018 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2019                                          struct ieee80211_rx_data *rx,
2020                                          struct sk_buff *skb)
2021 {
2022         ieee80211_rx_result res = RX_DROP_MONITOR;
2023
2024         rx->skb = skb;
2025         rx->sdata = sdata;
2026         rx->dev = sdata->dev;
2027
2028 #define CALL_RXH(rxh)                   \
2029         do {                            \
2030                 res = rxh(rx);          \
2031                 if (res != RX_CONTINUE) \
2032                         goto rxh_done;  \
2033         } while (0);
2034
2035         CALL_RXH(ieee80211_rx_h_passive_scan)
2036         CALL_RXH(ieee80211_rx_h_check)
2037         CALL_RXH(ieee80211_rx_h_decrypt)
2038         CALL_RXH(ieee80211_rx_h_check_more_data)
2039         CALL_RXH(ieee80211_rx_h_sta_process)
2040         CALL_RXH(ieee80211_rx_h_defragment)
2041         CALL_RXH(ieee80211_rx_h_ps_poll)
2042         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2043         /* must be after MMIC verify so header is counted in MPDU mic */
2044         CALL_RXH(ieee80211_rx_h_remove_qos_control)
2045         CALL_RXH(ieee80211_rx_h_amsdu)
2046 #ifdef CONFIG_MAC80211_MESH
2047         if (ieee80211_vif_is_mesh(&sdata->vif))
2048                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2049 #endif
2050         CALL_RXH(ieee80211_rx_h_data)
2051         CALL_RXH(ieee80211_rx_h_ctrl)
2052         CALL_RXH(ieee80211_rx_h_action)
2053         CALL_RXH(ieee80211_rx_h_mgmt)
2054
2055 #undef CALL_RXH
2056
2057  rxh_done:
2058         switch (res) {
2059         case RX_DROP_MONITOR:
2060                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2061                 if (rx->sta)
2062                         rx->sta->rx_dropped++;
2063                 /* fall through */
2064         case RX_CONTINUE:
2065                 ieee80211_rx_cooked_monitor(rx);
2066                 break;
2067         case RX_DROP_UNUSABLE:
2068                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2069                 if (rx->sta)
2070                         rx->sta->rx_dropped++;
2071                 dev_kfree_skb(rx->skb);
2072                 break;
2073         case RX_QUEUED:
2074                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2075                 break;
2076         }
2077 }
2078
2079 /* main receive path */
2080
2081 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2082                                 struct ieee80211_rx_data *rx,
2083                                 struct ieee80211_hdr *hdr)
2084 {
2085         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2086         int multicast = is_multicast_ether_addr(hdr->addr1);
2087
2088         switch (sdata->vif.type) {
2089         case NL80211_IFTYPE_STATION:
2090                 if (!bssid)
2091                         return 0;
2092                 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2093                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2094                                 return 0;
2095                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2096                 } else if (!multicast &&
2097                            compare_ether_addr(sdata->dev->dev_addr,
2098                                               hdr->addr1) != 0) {
2099                         if (!(sdata->dev->flags & IFF_PROMISC))
2100                                 return 0;
2101                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2102                 }
2103                 break;
2104         case NL80211_IFTYPE_ADHOC:
2105                 if (!bssid)
2106                         return 0;
2107                 if (ieee80211_is_beacon(hdr->frame_control)) {
2108                         return 1;
2109                 }
2110                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2111                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2112                                 return 0;
2113                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2114                 } else if (!multicast &&
2115                            compare_ether_addr(sdata->dev->dev_addr,
2116                                               hdr->addr1) != 0) {
2117                         if (!(sdata->dev->flags & IFF_PROMISC))
2118                                 return 0;
2119                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2120                 } else if (!rx->sta) {
2121                         int rate_idx;
2122                         if (rx->status->flag & RX_FLAG_HT)
2123                                 rate_idx = 0; /* TODO: HT rates */
2124                         else
2125                                 rate_idx = rx->status->rate_idx;
2126                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2127                                 BIT(rate_idx));
2128                 }
2129                 break;
2130         case NL80211_IFTYPE_MESH_POINT:
2131                 if (!multicast &&
2132                     compare_ether_addr(sdata->dev->dev_addr,
2133                                        hdr->addr1) != 0) {
2134                         if (!(sdata->dev->flags & IFF_PROMISC))
2135                                 return 0;
2136
2137                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2138                 }
2139                 break;
2140         case NL80211_IFTYPE_AP_VLAN:
2141         case NL80211_IFTYPE_AP:
2142                 if (!bssid) {
2143                         if (compare_ether_addr(sdata->dev->dev_addr,
2144                                                hdr->addr1))
2145                                 return 0;
2146                 } else if (!ieee80211_bssid_match(bssid,
2147                                         sdata->dev->dev_addr)) {
2148                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2149                                 return 0;
2150                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2151                 }
2152                 break;
2153         case NL80211_IFTYPE_WDS:
2154                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2155                         return 0;
2156                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2157                         return 0;
2158                 break;
2159         case NL80211_IFTYPE_MONITOR:
2160                 /* take everything */
2161                 break;
2162         case NL80211_IFTYPE_UNSPECIFIED:
2163         case __NL80211_IFTYPE_AFTER_LAST:
2164                 /* should never get here */
2165                 WARN_ON(1);
2166                 break;
2167         }
2168
2169         return 1;
2170 }
2171
2172 /*
2173  * This is the actual Rx frames handler. as it blongs to Rx path it must
2174  * be called with rcu_read_lock protection.
2175  */
2176 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2177                                          struct sk_buff *skb,
2178                                          struct ieee80211_rx_status *status,
2179                                          struct ieee80211_rate *rate)
2180 {
2181         struct ieee80211_local *local = hw_to_local(hw);
2182         struct ieee80211_sub_if_data *sdata;
2183         struct ieee80211_hdr *hdr;
2184         struct ieee80211_rx_data rx;
2185         int prepares;
2186         struct ieee80211_sub_if_data *prev = NULL;
2187         struct sk_buff *skb_new;
2188
2189         hdr = (struct ieee80211_hdr *)skb->data;
2190         memset(&rx, 0, sizeof(rx));
2191         rx.skb = skb;
2192         rx.local = local;
2193
2194         rx.status = status;
2195         rx.rate = rate;
2196
2197         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2198                 local->dot11ReceivedFragmentCount++;
2199
2200         rx.sta = sta_info_get(local, hdr->addr2);
2201         if (rx.sta) {
2202                 rx.sdata = rx.sta->sdata;
2203                 rx.dev = rx.sta->sdata->dev;
2204         }
2205
2206         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2207                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2208                 return;
2209         }
2210
2211         if (unlikely(local->sw_scanning || local->hw_scanning))
2212                 rx.flags |= IEEE80211_RX_IN_SCAN;
2213
2214         ieee80211_parse_qos(&rx);
2215         ieee80211_verify_alignment(&rx);
2216
2217         skb = rx.skb;
2218
2219         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2220                 if (!netif_running(sdata->dev))
2221                         continue;
2222
2223                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2224                         continue;
2225
2226                 rx.flags |= IEEE80211_RX_RA_MATCH;
2227                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2228
2229                 if (!prepares)
2230                         continue;
2231
2232                 /*
2233                  * frame is destined for this interface, but if it's not
2234                  * also for the previous one we handle that after the
2235                  * loop to avoid copying the SKB once too much
2236                  */
2237
2238                 if (!prev) {
2239                         prev = sdata;
2240                         continue;
2241                 }
2242
2243                 /*
2244                  * frame was destined for the previous interface
2245                  * so invoke RX handlers for it
2246                  */
2247
2248                 skb_new = skb_copy(skb, GFP_ATOMIC);
2249                 if (!skb_new) {
2250                         if (net_ratelimit())
2251                                 printk(KERN_DEBUG "%s: failed to copy "
2252                                        "multicast frame for %s\n",
2253                                        wiphy_name(local->hw.wiphy),
2254                                        prev->dev->name);
2255                         continue;
2256                 }
2257                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2258                 prev = sdata;
2259         }
2260         if (prev)
2261                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2262         else
2263                 dev_kfree_skb(skb);
2264 }
2265
2266 #define SEQ_MODULO 0x1000
2267 #define SEQ_MASK   0xfff
2268
2269 static inline int seq_less(u16 sq1, u16 sq2)
2270 {
2271         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2272 }
2273
2274 static inline u16 seq_inc(u16 sq)
2275 {
2276         return (sq + 1) & SEQ_MASK;
2277 }
2278
2279 static inline u16 seq_sub(u16 sq1, u16 sq2)
2280 {
2281         return (sq1 - sq2) & SEQ_MASK;
2282 }
2283
2284
2285 /*
2286  * As it function blongs to Rx path it must be called with
2287  * the proper rcu_read_lock protection for its flow.
2288  */
2289 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2290                                            struct tid_ampdu_rx *tid_agg_rx,
2291                                            struct sk_buff *skb,
2292                                            u16 mpdu_seq_num,
2293                                            int bar_req)
2294 {
2295         struct ieee80211_local *local = hw_to_local(hw);
2296         struct ieee80211_rx_status status;
2297         u16 head_seq_num, buf_size;
2298         int index;
2299         struct ieee80211_supported_band *sband;
2300         struct ieee80211_rate *rate;
2301
2302         buf_size = tid_agg_rx->buf_size;
2303         head_seq_num = tid_agg_rx->head_seq_num;
2304
2305         /* frame with out of date sequence number */
2306         if (seq_less(mpdu_seq_num, head_seq_num)) {
2307                 dev_kfree_skb(skb);
2308                 return 1;
2309         }
2310
2311         /* if frame sequence number exceeds our buffering window size or
2312          * block Ack Request arrived - release stored frames */
2313         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2314                 /* new head to the ordering buffer */
2315                 if (bar_req)
2316                         head_seq_num = mpdu_seq_num;
2317                 else
2318                         head_seq_num =
2319                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2320                 /* release stored frames up to new head to stack */
2321                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2322                         index = seq_sub(tid_agg_rx->head_seq_num,
2323                                 tid_agg_rx->ssn)
2324                                 % tid_agg_rx->buf_size;
2325
2326                         if (tid_agg_rx->reorder_buf[index]) {
2327                                 /* release the reordered frames to stack */
2328                                 memcpy(&status,
2329                                         tid_agg_rx->reorder_buf[index]->cb,
2330                                         sizeof(status));
2331                                 sband = local->hw.wiphy->bands[status.band];
2332                                 if (status.flag & RX_FLAG_HT) {
2333                                         /* TODO: HT rates */
2334                                         rate = sband->bitrates;
2335                                 } else {
2336                                         rate = &sband->bitrates
2337                                                 [status.rate_idx];
2338                                 }
2339                                 __ieee80211_rx_handle_packet(hw,
2340                                         tid_agg_rx->reorder_buf[index],
2341                                         &status, rate);
2342                                 tid_agg_rx->stored_mpdu_num--;
2343                                 tid_agg_rx->reorder_buf[index] = NULL;
2344                         }
2345                         tid_agg_rx->head_seq_num =
2346                                 seq_inc(tid_agg_rx->head_seq_num);
2347                 }
2348                 if (bar_req)
2349                         return 1;
2350         }
2351
2352         /* now the new frame is always in the range of the reordering */
2353         /* buffer window */
2354         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2355                                 % tid_agg_rx->buf_size;
2356         /* check if we already stored this frame */
2357         if (tid_agg_rx->reorder_buf[index]) {
2358                 dev_kfree_skb(skb);
2359                 return 1;
2360         }
2361
2362         /* if arrived mpdu is in the right order and nothing else stored */
2363         /* release it immediately */
2364         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2365                         tid_agg_rx->stored_mpdu_num == 0) {
2366                 tid_agg_rx->head_seq_num =
2367                         seq_inc(tid_agg_rx->head_seq_num);
2368                 return 0;
2369         }
2370
2371         /* put the frame in the reordering buffer */
2372         tid_agg_rx->reorder_buf[index] = skb;
2373         tid_agg_rx->stored_mpdu_num++;
2374         /* release the buffer until next missing frame */
2375         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2376                                                 % tid_agg_rx->buf_size;
2377         while (tid_agg_rx->reorder_buf[index]) {
2378                 /* release the reordered frame back to stack */
2379                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2380                         sizeof(status));
2381                 sband = local->hw.wiphy->bands[status.band];
2382                 if (status.flag & RX_FLAG_HT)
2383                         rate = sband->bitrates; /* TODO: HT rates */
2384                 else
2385                         rate = &sband->bitrates[status.rate_idx];
2386                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2387                                              &status, rate);
2388                 tid_agg_rx->stored_mpdu_num--;
2389                 tid_agg_rx->reorder_buf[index] = NULL;
2390                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2391                 index = seq_sub(tid_agg_rx->head_seq_num,
2392                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2393         }
2394         return 1;
2395 }
2396
2397 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2398                                      struct sk_buff *skb)
2399 {
2400         struct ieee80211_hw *hw = &local->hw;
2401         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2402         struct sta_info *sta;
2403         struct tid_ampdu_rx *tid_agg_rx;
2404         u16 sc;
2405         u16 mpdu_seq_num;
2406         u8 ret = 0;
2407         int tid;
2408
2409         sta = sta_info_get(local, hdr->addr2);
2410         if (!sta)
2411                 return ret;
2412
2413         /* filter the QoS data rx stream according to
2414          * STA/TID and check if this STA/TID is on aggregation */
2415         if (!ieee80211_is_data_qos(hdr->frame_control))
2416                 goto end_reorder;
2417
2418         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2419
2420         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2421                 goto end_reorder;
2422
2423         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2424
2425         /* qos null data frames are excluded */
2426         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2427                 goto end_reorder;
2428
2429         /* new un-ordered ampdu frame - process it */
2430
2431         /* reset session timer */
2432         if (tid_agg_rx->timeout)
2433                 mod_timer(&tid_agg_rx->session_timer,
2434                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2435
2436         /* if this mpdu is fragmented - terminate rx aggregation session */
2437         sc = le16_to_cpu(hdr->seq_ctrl);
2438         if (sc & IEEE80211_SCTL_FRAG) {
2439                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2440                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2441                 ret = 1;
2442                 goto end_reorder;
2443         }
2444
2445         /* according to mpdu sequence number deal with reordering buffer */
2446         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2447         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2448                                                 mpdu_seq_num, 0);
2449  end_reorder:
2450         return ret;
2451 }
2452
2453 /*
2454  * This is the receive path handler. It is called by a low level driver when an
2455  * 802.11 MPDU is received from the hardware.
2456  */
2457 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2458                     struct ieee80211_rx_status *status)
2459 {
2460         struct ieee80211_local *local = hw_to_local(hw);
2461         struct ieee80211_rate *rate = NULL;
2462         struct ieee80211_supported_band *sband;
2463
2464         if (status->band < 0 ||
2465             status->band >= IEEE80211_NUM_BANDS) {
2466                 WARN_ON(1);
2467                 return;
2468         }
2469
2470         sband = local->hw.wiphy->bands[status->band];
2471         if (!sband) {
2472                 WARN_ON(1);
2473                 return;
2474         }
2475
2476         if (status->flag & RX_FLAG_HT) {
2477                 /* rate_idx is MCS index */
2478                 if (WARN_ON(status->rate_idx < 0 ||
2479                             status->rate_idx >= 76))
2480                         return;
2481                 /* HT rates are not in the table - use the highest legacy rate
2482                  * for now since other parts of mac80211 may not yet be fully
2483                  * MCS aware. */
2484                 rate = &sband->bitrates[sband->n_bitrates - 1];
2485         } else {
2486                 if (WARN_ON(status->rate_idx < 0 ||
2487                             status->rate_idx >= sband->n_bitrates))
2488                         return;
2489                 rate = &sband->bitrates[status->rate_idx];
2490         }
2491
2492         /*
2493          * key references and virtual interfaces are protected using RCU
2494          * and this requires that we are in a read-side RCU section during
2495          * receive processing
2496          */
2497         rcu_read_lock();
2498
2499         /*
2500          * Frames with failed FCS/PLCP checksum are not returned,
2501          * all other frames are returned without radiotap header
2502          * if it was previously present.
2503          * Also, frames with less than 16 bytes are dropped.
2504          */
2505         skb = ieee80211_rx_monitor(local, skb, status, rate);
2506         if (!skb) {
2507                 rcu_read_unlock();
2508                 return;
2509         }
2510
2511         if (!ieee80211_rx_reorder_ampdu(local, skb))
2512                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2513
2514         rcu_read_unlock();
2515 }
2516 EXPORT_SYMBOL(__ieee80211_rx);
2517
2518 /* This is a version of the rx handler that can be called from hard irq
2519  * context. Post the skb on the queue and schedule the tasklet */
2520 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2521                           struct ieee80211_rx_status *status)
2522 {
2523         struct ieee80211_local *local = hw_to_local(hw);
2524
2525         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2526
2527         skb->dev = local->mdev;
2528         /* copy status into skb->cb for use by tasklet */
2529         memcpy(skb->cb, status, sizeof(*status));
2530         skb->pkt_type = IEEE80211_RX_MSG;
2531         skb_queue_tail(&local->skb_queue, skb);
2532         tasklet_schedule(&local->tasklet);
2533 }
2534 EXPORT_SYMBOL(ieee80211_rx_irqsafe);