mac80211: remove mixed-cell and userspace MLME code
[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         sta->rx_fragments++;
860         sta->rx_bytes += rx->skb->len;
861         sta->last_signal = rx->status->signal;
862         sta->last_qual = rx->status->qual;
863         sta->last_noise = rx->status->noise;
864
865         /*
866          * Change STA power saving mode only at the end of a frame
867          * exchange sequence.
868          */
869         if (!ieee80211_has_morefrags(hdr->frame_control) &&
870             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
871              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
872                 if (test_sta_flags(sta, WLAN_STA_PS)) {
873                         /*
874                          * Ignore doze->wake transitions that are
875                          * indicated by non-data frames, the standard
876                          * is unclear here, but for example going to
877                          * PS mode and then scanning would cause a
878                          * doze->wake transition for the probe request,
879                          * and that is clearly undesirable.
880                          */
881                         if (ieee80211_is_data(hdr->frame_control) &&
882                             !ieee80211_has_pm(hdr->frame_control))
883                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
884                 } else {
885                         if (ieee80211_has_pm(hdr->frame_control))
886                                 ap_sta_ps_start(sta);
887                 }
888         }
889
890         /* Drop data::nullfunc frames silently, since they are used only to
891          * control station power saving mode. */
892         if (ieee80211_is_nullfunc(hdr->frame_control)) {
893                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
894                 /* Update counter and free packet here to avoid counting this
895                  * as a dropped packed. */
896                 sta->rx_packets++;
897                 dev_kfree_skb(rx->skb);
898                 return RX_QUEUED;
899         }
900
901         return RX_CONTINUE;
902 } /* ieee80211_rx_h_sta_process */
903
904 static inline struct ieee80211_fragment_entry *
905 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
906                          unsigned int frag, unsigned int seq, int rx_queue,
907                          struct sk_buff **skb)
908 {
909         struct ieee80211_fragment_entry *entry;
910         int idx;
911
912         idx = sdata->fragment_next;
913         entry = &sdata->fragments[sdata->fragment_next++];
914         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
915                 sdata->fragment_next = 0;
916
917         if (!skb_queue_empty(&entry->skb_list)) {
918 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
919                 struct ieee80211_hdr *hdr =
920                         (struct ieee80211_hdr *) entry->skb_list.next->data;
921                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
922                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
923                        "addr1=%pM addr2=%pM\n",
924                        sdata->dev->name, idx,
925                        jiffies - entry->first_frag_time, entry->seq,
926                        entry->last_frag, hdr->addr1, hdr->addr2);
927 #endif
928                 __skb_queue_purge(&entry->skb_list);
929         }
930
931         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
932         *skb = NULL;
933         entry->first_frag_time = jiffies;
934         entry->seq = seq;
935         entry->rx_queue = rx_queue;
936         entry->last_frag = frag;
937         entry->ccmp = 0;
938         entry->extra_len = 0;
939
940         return entry;
941 }
942
943 static inline struct ieee80211_fragment_entry *
944 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
945                           unsigned int frag, unsigned int seq,
946                           int rx_queue, struct ieee80211_hdr *hdr)
947 {
948         struct ieee80211_fragment_entry *entry;
949         int i, idx;
950
951         idx = sdata->fragment_next;
952         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
953                 struct ieee80211_hdr *f_hdr;
954
955                 idx--;
956                 if (idx < 0)
957                         idx = IEEE80211_FRAGMENT_MAX - 1;
958
959                 entry = &sdata->fragments[idx];
960                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
961                     entry->rx_queue != rx_queue ||
962                     entry->last_frag + 1 != frag)
963                         continue;
964
965                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
966
967                 /*
968                  * Check ftype and addresses are equal, else check next fragment
969                  */
970                 if (((hdr->frame_control ^ f_hdr->frame_control) &
971                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
972                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
973                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
974                         continue;
975
976                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
977                         __skb_queue_purge(&entry->skb_list);
978                         continue;
979                 }
980                 return entry;
981         }
982
983         return NULL;
984 }
985
986 static ieee80211_rx_result debug_noinline
987 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
988 {
989         struct ieee80211_hdr *hdr;
990         u16 sc;
991         __le16 fc;
992         unsigned int frag, seq;
993         struct ieee80211_fragment_entry *entry;
994         struct sk_buff *skb;
995
996         hdr = (struct ieee80211_hdr *)rx->skb->data;
997         fc = hdr->frame_control;
998         sc = le16_to_cpu(hdr->seq_ctrl);
999         frag = sc & IEEE80211_SCTL_FRAG;
1000
1001         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1002                    (rx->skb)->len < 24 ||
1003                    is_multicast_ether_addr(hdr->addr1))) {
1004                 /* not fragmented */
1005                 goto out;
1006         }
1007         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1008
1009         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1010
1011         if (frag == 0) {
1012                 /* This is the first fragment of a new frame. */
1013                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1014                                                  rx->queue, &(rx->skb));
1015                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1016                     ieee80211_has_protected(fc)) {
1017                         /* Store CCMP PN so that we can verify that the next
1018                          * fragment has a sequential PN value. */
1019                         entry->ccmp = 1;
1020                         memcpy(entry->last_pn,
1021                                rx->key->u.ccmp.rx_pn[rx->queue],
1022                                CCMP_PN_LEN);
1023                 }
1024                 return RX_QUEUED;
1025         }
1026
1027         /* This is a fragment for a frame that should already be pending in
1028          * fragment cache. Add this fragment to the end of the pending entry.
1029          */
1030         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1031         if (!entry) {
1032                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1033                 return RX_DROP_MONITOR;
1034         }
1035
1036         /* Verify that MPDUs within one MSDU have sequential PN values.
1037          * (IEEE 802.11i, 8.3.3.4.5) */
1038         if (entry->ccmp) {
1039                 int i;
1040                 u8 pn[CCMP_PN_LEN], *rpn;
1041                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1042                         return RX_DROP_UNUSABLE;
1043                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1044                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1045                         pn[i]++;
1046                         if (pn[i])
1047                                 break;
1048                 }
1049                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1050                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1051                         return RX_DROP_UNUSABLE;
1052                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1053         }
1054
1055         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1056         __skb_queue_tail(&entry->skb_list, rx->skb);
1057         entry->last_frag = frag;
1058         entry->extra_len += rx->skb->len;
1059         if (ieee80211_has_morefrags(fc)) {
1060                 rx->skb = NULL;
1061                 return RX_QUEUED;
1062         }
1063
1064         rx->skb = __skb_dequeue(&entry->skb_list);
1065         if (skb_tailroom(rx->skb) < entry->extra_len) {
1066                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1067                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1068                                               GFP_ATOMIC))) {
1069                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1070                         __skb_queue_purge(&entry->skb_list);
1071                         return RX_DROP_UNUSABLE;
1072                 }
1073         }
1074         while ((skb = __skb_dequeue(&entry->skb_list))) {
1075                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1076                 dev_kfree_skb(skb);
1077         }
1078
1079         /* Complete frame has been reassembled - process it now */
1080         rx->flags |= IEEE80211_RX_FRAGMENTED;
1081
1082  out:
1083         if (rx->sta)
1084                 rx->sta->rx_packets++;
1085         if (is_multicast_ether_addr(hdr->addr1))
1086                 rx->local->dot11MulticastReceivedFrameCount++;
1087         else
1088                 ieee80211_led_rx(rx->local);
1089         return RX_CONTINUE;
1090 }
1091
1092 static ieee80211_rx_result debug_noinline
1093 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1094 {
1095         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1096         struct sk_buff *skb;
1097         int no_pending_pkts;
1098         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1099
1100         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1101                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1102                 return RX_CONTINUE;
1103
1104         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1105             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1106                 return RX_DROP_UNUSABLE;
1107
1108         skb = skb_dequeue(&rx->sta->tx_filtered);
1109         if (!skb) {
1110                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1111                 if (skb)
1112                         rx->local->total_ps_buffered--;
1113         }
1114         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1115                 skb_queue_empty(&rx->sta->ps_tx_buf);
1116
1117         if (skb) {
1118                 struct ieee80211_hdr *hdr =
1119                         (struct ieee80211_hdr *) skb->data;
1120
1121                 /*
1122                  * Tell TX path to send one frame even though the STA may
1123                  * still remain is PS mode after this frame exchange.
1124                  */
1125                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1126
1127 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1128                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1129                        rx->sta->sta.addr, rx->sta->sta.aid,
1130                        skb_queue_len(&rx->sta->ps_tx_buf));
1131 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1132
1133                 /* Use MoreData flag to indicate whether there are more
1134                  * buffered frames for this STA */
1135                 if (no_pending_pkts)
1136                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1137                 else
1138                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1139
1140                 dev_queue_xmit(skb);
1141
1142                 if (no_pending_pkts)
1143                         sta_info_clear_tim_bit(rx->sta);
1144 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1145         } else if (!rx->sent_ps_buffered) {
1146                 /*
1147                  * FIXME: This can be the result of a race condition between
1148                  *        us expiring a frame and the station polling for it.
1149                  *        Should we send it a null-func frame indicating we
1150                  *        have nothing buffered for it?
1151                  */
1152                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1153                        "though there are no buffered frames for it\n",
1154                        rx->dev->name, rx->sta->sta.addr);
1155 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1156         }
1157
1158         /* Free PS Poll skb here instead of returning RX_DROP that would
1159          * count as an dropped frame. */
1160         dev_kfree_skb(rx->skb);
1161
1162         return RX_QUEUED;
1163 }
1164
1165 static ieee80211_rx_result debug_noinline
1166 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1167 {
1168         u8 *data = rx->skb->data;
1169         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1170
1171         if (!ieee80211_is_data_qos(hdr->frame_control))
1172                 return RX_CONTINUE;
1173
1174         /* remove the qos control field, update frame type and meta-data */
1175         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1176                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1177         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1178         /* change frame type to non QOS */
1179         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1180
1181         return RX_CONTINUE;
1182 }
1183
1184 static int
1185 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1186 {
1187         if (unlikely(!rx->sta ||
1188             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1189                 return -EACCES;
1190
1191         return 0;
1192 }
1193
1194 static int
1195 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1196 {
1197         /*
1198          * Pass through unencrypted frames if the hardware has
1199          * decrypted them already.
1200          */
1201         if (rx->status->flag & RX_FLAG_DECRYPTED)
1202                 return 0;
1203
1204         /* Drop unencrypted frames if key is set. */
1205         if (unlikely(!ieee80211_has_protected(fc) &&
1206                      !ieee80211_is_nullfunc(fc) &&
1207                      (!ieee80211_is_mgmt(fc) ||
1208                       (ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1209                        rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP))) &&
1210                      (rx->key || rx->sdata->drop_unencrypted)))
1211                 return -EACCES;
1212         /* BIP does not use Protected field, so need to check MMIE */
1213         if (unlikely(rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP) &&
1214                      ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1215                      ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1216                      (rx->key || rx->sdata->drop_unencrypted)))
1217                 return -EACCES;
1218
1219         return 0;
1220 }
1221
1222 static int
1223 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1224 {
1225         struct net_device *dev = rx->dev;
1226         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1227         u16 hdrlen, ethertype;
1228         u8 *payload;
1229         u8 dst[ETH_ALEN];
1230         u8 src[ETH_ALEN] __aligned(2);
1231         struct sk_buff *skb = rx->skb;
1232         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1233
1234         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1235                 return -1;
1236
1237         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1238
1239         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1240          * header
1241          * IEEE 802.11 address fields:
1242          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1243          *   0     0   DA    SA    BSSID n/a
1244          *   0     1   DA    BSSID SA    n/a
1245          *   1     0   BSSID SA    DA    n/a
1246          *   1     1   RA    TA    DA    SA
1247          */
1248         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1249         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1250
1251         switch (hdr->frame_control &
1252                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1253         case cpu_to_le16(IEEE80211_FCTL_TODS):
1254                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1255                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1256                         return -1;
1257                 break;
1258         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1259                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1260                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1261                         return -1;
1262                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1263                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1264                                 (skb->data + hdrlen);
1265                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1266                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1267                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1268                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1269                         }
1270                 }
1271                 break;
1272         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1273                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1274                     (is_multicast_ether_addr(dst) &&
1275                      !compare_ether_addr(src, dev->dev_addr)))
1276                         return -1;
1277                 break;
1278         case cpu_to_le16(0):
1279                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1280                         return -1;
1281                 break;
1282         }
1283
1284         if (unlikely(skb->len - hdrlen < 8))
1285                 return -1;
1286
1287         payload = skb->data + hdrlen;
1288         ethertype = (payload[6] << 8) | payload[7];
1289
1290         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1291                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1292                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1293                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1294                  * replace EtherType */
1295                 skb_pull(skb, hdrlen + 6);
1296                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1297                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1298         } else {
1299                 struct ethhdr *ehdr;
1300                 __be16 len;
1301
1302                 skb_pull(skb, hdrlen);
1303                 len = htons(skb->len);
1304                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1305                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1306                 memcpy(ehdr->h_source, src, ETH_ALEN);
1307                 ehdr->h_proto = len;
1308         }
1309         return 0;
1310 }
1311
1312 /*
1313  * requires that rx->skb is a frame with ethernet header
1314  */
1315 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1316 {
1317         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1318                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1319         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1320
1321         /*
1322          * Allow EAPOL frames to us/the PAE group address regardless
1323          * of whether the frame was encrypted or not.
1324          */
1325         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1326             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1327              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1328                 return true;
1329
1330         if (ieee80211_802_1x_port_control(rx) ||
1331             ieee80211_drop_unencrypted(rx, fc))
1332                 return false;
1333
1334         return true;
1335 }
1336
1337 /*
1338  * requires that rx->skb is a frame with ethernet header
1339  */
1340 static void
1341 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1342 {
1343         struct net_device *dev = rx->dev;
1344         struct ieee80211_local *local = rx->local;
1345         struct sk_buff *skb, *xmit_skb;
1346         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1347         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1348         struct sta_info *dsta;
1349
1350         skb = rx->skb;
1351         xmit_skb = NULL;
1352
1353         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1354              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1355             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1356             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1357                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1358                         /*
1359                          * send multicast frames both to higher layers in
1360                          * local net stack and back to the wireless medium
1361                          */
1362                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1363                         if (!xmit_skb && net_ratelimit())
1364                                 printk(KERN_DEBUG "%s: failed to clone "
1365                                        "multicast frame\n", dev->name);
1366                 } else {
1367                         dsta = sta_info_get(local, skb->data);
1368                         if (dsta && dsta->sdata->dev == dev) {
1369                                 /*
1370                                  * The destination station is associated to
1371                                  * this AP (in this VLAN), so send the frame
1372                                  * directly to it and do not pass it to local
1373                                  * net stack.
1374                                  */
1375                                 xmit_skb = skb;
1376                                 skb = NULL;
1377                         }
1378                 }
1379         }
1380
1381         if (skb) {
1382                 int align __maybe_unused;
1383
1384 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1385                 /*
1386                  * 'align' will only take the values 0 or 2 here
1387                  * since all frames are required to be aligned
1388                  * to 2-byte boundaries when being passed to
1389                  * mac80211. That also explains the __skb_push()
1390                  * below.
1391                  */
1392                 align = (unsigned long)skb->data & 4;
1393                 if (align) {
1394                         if (WARN_ON(skb_headroom(skb) < 3)) {
1395                                 dev_kfree_skb(skb);
1396                                 skb = NULL;
1397                         } else {
1398                                 u8 *data = skb->data;
1399                                 size_t len = skb->len;
1400                                 u8 *new = __skb_push(skb, align);
1401                                 memmove(new, data, len);
1402                                 __skb_trim(skb, len);
1403                         }
1404                 }
1405 #endif
1406
1407                 if (skb) {
1408                         /* deliver to local stack */
1409                         skb->protocol = eth_type_trans(skb, dev);
1410                         memset(skb->cb, 0, sizeof(skb->cb));
1411                         netif_rx(skb);
1412                 }
1413         }
1414
1415         if (xmit_skb) {
1416                 /* send to wireless media */
1417                 xmit_skb->protocol = htons(ETH_P_802_3);
1418                 skb_reset_network_header(xmit_skb);
1419                 skb_reset_mac_header(xmit_skb);
1420                 dev_queue_xmit(xmit_skb);
1421         }
1422 }
1423
1424 static ieee80211_rx_result debug_noinline
1425 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1426 {
1427         struct net_device *dev = rx->dev;
1428         struct ieee80211_local *local = rx->local;
1429         u16 ethertype;
1430         u8 *payload;
1431         struct sk_buff *skb = rx->skb, *frame = NULL;
1432         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1433         __le16 fc = hdr->frame_control;
1434         const struct ethhdr *eth;
1435         int remaining, err;
1436         u8 dst[ETH_ALEN];
1437         u8 src[ETH_ALEN];
1438
1439         if (unlikely(!ieee80211_is_data(fc)))
1440                 return RX_CONTINUE;
1441
1442         if (unlikely(!ieee80211_is_data_present(fc)))
1443                 return RX_DROP_MONITOR;
1444
1445         if (!(rx->flags & IEEE80211_RX_AMSDU))
1446                 return RX_CONTINUE;
1447
1448         err = ieee80211_data_to_8023(rx);
1449         if (unlikely(err))
1450                 return RX_DROP_UNUSABLE;
1451
1452         skb->dev = dev;
1453
1454         dev->stats.rx_packets++;
1455         dev->stats.rx_bytes += skb->len;
1456
1457         /* skip the wrapping header */
1458         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1459         if (!eth)
1460                 return RX_DROP_UNUSABLE;
1461
1462         while (skb != frame) {
1463                 u8 padding;
1464                 __be16 len = eth->h_proto;
1465                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1466
1467                 remaining = skb->len;
1468                 memcpy(dst, eth->h_dest, ETH_ALEN);
1469                 memcpy(src, eth->h_source, ETH_ALEN);
1470
1471                 padding = ((4 - subframe_len) & 0x3);
1472                 /* the last MSDU has no padding */
1473                 if (subframe_len > remaining)
1474                         return RX_DROP_UNUSABLE;
1475
1476                 skb_pull(skb, sizeof(struct ethhdr));
1477                 /* if last subframe reuse skb */
1478                 if (remaining <= subframe_len + padding)
1479                         frame = skb;
1480                 else {
1481                         /*
1482                          * Allocate and reserve two bytes more for payload
1483                          * alignment since sizeof(struct ethhdr) is 14.
1484                          */
1485                         frame = dev_alloc_skb(
1486                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1487                                 subframe_len + 2);
1488
1489                         if (frame == NULL)
1490                                 return RX_DROP_UNUSABLE;
1491
1492                         skb_reserve(frame,
1493                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1494                                     sizeof(struct ethhdr) + 2);
1495                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1496                                 ntohs(len));
1497
1498                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1499                                                         padding);
1500                         if (!eth) {
1501                                 dev_kfree_skb(frame);
1502                                 return RX_DROP_UNUSABLE;
1503                         }
1504                 }
1505
1506                 skb_reset_network_header(frame);
1507                 frame->dev = dev;
1508                 frame->priority = skb->priority;
1509                 rx->skb = frame;
1510
1511                 payload = frame->data;
1512                 ethertype = (payload[6] << 8) | payload[7];
1513
1514                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1515                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1516                            compare_ether_addr(payload,
1517                                               bridge_tunnel_header) == 0)) {
1518                         /* remove RFC1042 or Bridge-Tunnel
1519                          * encapsulation and replace EtherType */
1520                         skb_pull(frame, 6);
1521                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1522                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1523                 } else {
1524                         memcpy(skb_push(frame, sizeof(__be16)),
1525                                &len, sizeof(__be16));
1526                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1527                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1528                 }
1529
1530                 if (!ieee80211_frame_allowed(rx, fc)) {
1531                         if (skb == frame) /* last frame */
1532                                 return RX_DROP_UNUSABLE;
1533                         dev_kfree_skb(frame);
1534                         continue;
1535                 }
1536
1537                 ieee80211_deliver_skb(rx);
1538         }
1539
1540         return RX_QUEUED;
1541 }
1542
1543 #ifdef CONFIG_MAC80211_MESH
1544 static ieee80211_rx_result
1545 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1546 {
1547         struct ieee80211_hdr *hdr;
1548         struct ieee80211s_hdr *mesh_hdr;
1549         unsigned int hdrlen;
1550         struct sk_buff *skb = rx->skb, *fwd_skb;
1551
1552         hdr = (struct ieee80211_hdr *) skb->data;
1553         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1554         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1555
1556         if (!ieee80211_is_data(hdr->frame_control))
1557                 return RX_CONTINUE;
1558
1559         if (!mesh_hdr->ttl)
1560                 /* illegal frame */
1561                 return RX_DROP_MONITOR;
1562
1563         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1564                 struct ieee80211_sub_if_data *sdata;
1565                 struct mesh_path *mppath;
1566
1567                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1568                 rcu_read_lock();
1569                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1570                 if (!mppath) {
1571                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1572                 } else {
1573                         spin_lock_bh(&mppath->state_lock);
1574                         mppath->exp_time = jiffies;
1575                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1576                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1577                         spin_unlock_bh(&mppath->state_lock);
1578                 }
1579                 rcu_read_unlock();
1580         }
1581
1582         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1583                 return RX_CONTINUE;
1584
1585         mesh_hdr->ttl--;
1586
1587         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1588                 if (!mesh_hdr->ttl)
1589                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1590                                                      dropped_frames_ttl);
1591                 else {
1592                         struct ieee80211_hdr *fwd_hdr;
1593                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1594
1595                         if (!fwd_skb && net_ratelimit())
1596                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1597                                                    rx->dev->name);
1598
1599                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1600                         /*
1601                          * Save TA to addr1 to send TA a path error if a
1602                          * suitable next hop is not found
1603                          */
1604                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1605                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1606                         fwd_skb->dev = rx->local->mdev;
1607                         fwd_skb->iif = rx->dev->ifindex;
1608                         dev_queue_xmit(fwd_skb);
1609                 }
1610         }
1611
1612         if (is_multicast_ether_addr(hdr->addr3) ||
1613             rx->dev->flags & IFF_PROMISC)
1614                 return RX_CONTINUE;
1615         else
1616                 return RX_DROP_MONITOR;
1617 }
1618 #endif
1619
1620 static ieee80211_rx_result debug_noinline
1621 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1622 {
1623         struct net_device *dev = rx->dev;
1624         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1625         __le16 fc = hdr->frame_control;
1626         int err;
1627
1628         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1629                 return RX_CONTINUE;
1630
1631         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1632                 return RX_DROP_MONITOR;
1633
1634         err = ieee80211_data_to_8023(rx);
1635         if (unlikely(err))
1636                 return RX_DROP_UNUSABLE;
1637
1638         if (!ieee80211_frame_allowed(rx, fc))
1639                 return RX_DROP_MONITOR;
1640
1641         rx->skb->dev = dev;
1642
1643         dev->stats.rx_packets++;
1644         dev->stats.rx_bytes += rx->skb->len;
1645
1646         ieee80211_deliver_skb(rx);
1647
1648         return RX_QUEUED;
1649 }
1650
1651 static ieee80211_rx_result debug_noinline
1652 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1653 {
1654         struct ieee80211_local *local = rx->local;
1655         struct ieee80211_hw *hw = &local->hw;
1656         struct sk_buff *skb = rx->skb;
1657         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1658         struct tid_ampdu_rx *tid_agg_rx;
1659         u16 start_seq_num;
1660         u16 tid;
1661
1662         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1663                 return RX_CONTINUE;
1664
1665         if (ieee80211_is_back_req(bar->frame_control)) {
1666                 if (!rx->sta)
1667                         return RX_CONTINUE;
1668                 tid = le16_to_cpu(bar->control) >> 12;
1669                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1670                                         != HT_AGG_STATE_OPERATIONAL)
1671                         return RX_CONTINUE;
1672                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1673
1674                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1675
1676                 /* reset session timer */
1677                 if (tid_agg_rx->timeout)
1678                         mod_timer(&tid_agg_rx->session_timer,
1679                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1680
1681                 /* manage reordering buffer according to requested */
1682                 /* sequence number */
1683                 rcu_read_lock();
1684                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1685                                                  start_seq_num, 1);
1686                 rcu_read_unlock();
1687                 return RX_DROP_UNUSABLE;
1688         }
1689
1690         return RX_CONTINUE;
1691 }
1692
1693 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1694                                            struct ieee80211_mgmt *mgmt,
1695                                            size_t len)
1696 {
1697         struct ieee80211_local *local = sdata->local;
1698         struct sk_buff *skb;
1699         struct ieee80211_mgmt *resp;
1700
1701         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1702                 /* Not to own unicast address */
1703                 return;
1704         }
1705
1706         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1707             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1708                 /* Not from the current AP. */
1709                 return;
1710         }
1711
1712         if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1713                 /* Association in progress; ignore SA Query */
1714                 return;
1715         }
1716
1717         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1718                 /* Too short SA Query request frame */
1719                 return;
1720         }
1721
1722         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1723         if (skb == NULL)
1724                 return;
1725
1726         skb_reserve(skb, local->hw.extra_tx_headroom);
1727         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1728         memset(resp, 0, 24);
1729         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1730         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1731         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1732         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1733                                           IEEE80211_STYPE_ACTION);
1734         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1735         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1736         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1737         memcpy(resp->u.action.u.sa_query.trans_id,
1738                mgmt->u.action.u.sa_query.trans_id,
1739                WLAN_SA_QUERY_TR_ID_LEN);
1740
1741         ieee80211_tx_skb(sdata, skb, 1);
1742 }
1743
1744 static ieee80211_rx_result debug_noinline
1745 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1746 {
1747         struct ieee80211_local *local = rx->local;
1748         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1749         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1750         struct ieee80211_bss *bss;
1751         int len = rx->skb->len;
1752
1753         if (!ieee80211_is_action(mgmt->frame_control))
1754                 return RX_CONTINUE;
1755
1756         if (!rx->sta)
1757                 return RX_DROP_MONITOR;
1758
1759         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1760                 return RX_DROP_MONITOR;
1761
1762         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1763                 return RX_DROP_MONITOR;
1764
1765         /* all categories we currently handle have action_code */
1766         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1767                 return RX_DROP_MONITOR;
1768
1769         switch (mgmt->u.action.category) {
1770         case WLAN_CATEGORY_BACK:
1771                 /*
1772                  * The aggregation code is not prepared to handle
1773                  * anything but STA/AP due to the BSSID handling;
1774                  * IBSS could work in the code but isn't supported
1775                  * by drivers or the standard.
1776                  */
1777                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1778                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1779                     sdata->vif.type != NL80211_IFTYPE_AP)
1780                         return RX_DROP_MONITOR;
1781
1782                 switch (mgmt->u.action.u.addba_req.action_code) {
1783                 case WLAN_ACTION_ADDBA_REQ:
1784                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1785                                    sizeof(mgmt->u.action.u.addba_req)))
1786                                 return RX_DROP_MONITOR;
1787                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1788                         break;
1789                 case WLAN_ACTION_ADDBA_RESP:
1790                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1791                                    sizeof(mgmt->u.action.u.addba_resp)))
1792                                 return RX_DROP_MONITOR;
1793                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1794                         break;
1795                 case WLAN_ACTION_DELBA:
1796                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1797                                    sizeof(mgmt->u.action.u.delba)))
1798                                 return RX_DROP_MONITOR;
1799                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1800                         break;
1801                 }
1802                 break;
1803         case WLAN_CATEGORY_SPECTRUM_MGMT:
1804                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1805                         return RX_DROP_MONITOR;
1806
1807                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1808                         return RX_DROP_MONITOR;
1809
1810                 switch (mgmt->u.action.u.measurement.action_code) {
1811                 case WLAN_ACTION_SPCT_MSR_REQ:
1812                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1813                                    sizeof(mgmt->u.action.u.measurement)))
1814                                 return RX_DROP_MONITOR;
1815                         ieee80211_process_measurement_req(sdata, mgmt, len);
1816                         break;
1817                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1818                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1819                                    sizeof(mgmt->u.action.u.chan_switch)))
1820                                 return RX_DROP_MONITOR;
1821
1822                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1823                                 return RX_DROP_MONITOR;
1824
1825                         bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1826                                            local->hw.conf.channel->center_freq,
1827                                            sdata->u.mgd.ssid,
1828                                            sdata->u.mgd.ssid_len);
1829                         if (!bss)
1830                                 return RX_DROP_MONITOR;
1831
1832                         ieee80211_process_chanswitch(sdata,
1833                                      &mgmt->u.action.u.chan_switch.sw_elem, bss);
1834                         ieee80211_rx_bss_put(local, bss);
1835                         break;
1836                 }
1837                 break;
1838         case WLAN_CATEGORY_SA_QUERY:
1839                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1840                            sizeof(mgmt->u.action.u.sa_query)))
1841                         return RX_DROP_MONITOR;
1842                 switch (mgmt->u.action.u.sa_query.action) {
1843                 case WLAN_ACTION_SA_QUERY_REQUEST:
1844                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1845                                 return RX_DROP_MONITOR;
1846                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1847                         break;
1848                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1849                         /*
1850                          * SA Query response is currently only used in AP mode
1851                          * and it is processed in user space.
1852                          */
1853                         return RX_CONTINUE;
1854                 }
1855                 break;
1856         default:
1857                 return RX_CONTINUE;
1858         }
1859
1860         rx->sta->rx_packets++;
1861         dev_kfree_skb(rx->skb);
1862         return RX_QUEUED;
1863 }
1864
1865 static ieee80211_rx_result debug_noinline
1866 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1867 {
1868         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1869         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1870
1871         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1872                 return RX_DROP_MONITOR;
1873
1874         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1875                 return RX_DROP_MONITOR;
1876
1877         if (ieee80211_vif_is_mesh(&sdata->vif))
1878                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1879
1880         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1881                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1882
1883         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1884                 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1885
1886         return RX_DROP_MONITOR;
1887 }
1888
1889 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1890                                             struct ieee80211_hdr *hdr,
1891                                             struct ieee80211_rx_data *rx)
1892 {
1893         int keyidx;
1894         unsigned int hdrlen;
1895
1896         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1897         if (rx->skb->len >= hdrlen + 4)
1898                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1899         else
1900                 keyidx = -1;
1901
1902         if (!rx->sta) {
1903                 /*
1904                  * Some hardware seem to generate incorrect Michael MIC
1905                  * reports; ignore them to avoid triggering countermeasures.
1906                  */
1907                 goto ignore;
1908         }
1909
1910         if (!ieee80211_has_protected(hdr->frame_control))
1911                 goto ignore;
1912
1913         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1914                 /*
1915                  * APs with pairwise keys should never receive Michael MIC
1916                  * errors for non-zero keyidx because these are reserved for
1917                  * group keys and only the AP is sending real multicast
1918                  * frames in the BSS.
1919                  */
1920                 goto ignore;
1921         }
1922
1923         if (!ieee80211_is_data(hdr->frame_control) &&
1924             !ieee80211_is_auth(hdr->frame_control))
1925                 goto ignore;
1926
1927         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1928  ignore:
1929         dev_kfree_skb(rx->skb);
1930         rx->skb = NULL;
1931 }
1932
1933 /* TODO: use IEEE80211_RX_FRAGMENTED */
1934 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1935 {
1936         struct ieee80211_sub_if_data *sdata;
1937         struct ieee80211_local *local = rx->local;
1938         struct ieee80211_rtap_hdr {
1939                 struct ieee80211_radiotap_header hdr;
1940                 u8 flags;
1941                 u8 rate;
1942                 __le16 chan_freq;
1943                 __le16 chan_flags;
1944         } __attribute__ ((packed)) *rthdr;
1945         struct sk_buff *skb = rx->skb, *skb2;
1946         struct net_device *prev_dev = NULL;
1947         struct ieee80211_rx_status *status = rx->status;
1948
1949         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1950                 goto out_free_skb;
1951
1952         if (skb_headroom(skb) < sizeof(*rthdr) &&
1953             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1954                 goto out_free_skb;
1955
1956         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1957         memset(rthdr, 0, sizeof(*rthdr));
1958         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1959         rthdr->hdr.it_present =
1960                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1961                             (1 << IEEE80211_RADIOTAP_RATE) |
1962                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1963
1964         rthdr->rate = rx->rate->bitrate / 5;
1965         rthdr->chan_freq = cpu_to_le16(status->freq);
1966
1967         if (status->band == IEEE80211_BAND_5GHZ)
1968                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1969                                                 IEEE80211_CHAN_5GHZ);
1970         else
1971                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1972                                                 IEEE80211_CHAN_2GHZ);
1973
1974         skb_set_mac_header(skb, 0);
1975         skb->ip_summed = CHECKSUM_UNNECESSARY;
1976         skb->pkt_type = PACKET_OTHERHOST;
1977         skb->protocol = htons(ETH_P_802_2);
1978
1979         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1980                 if (!netif_running(sdata->dev))
1981                         continue;
1982
1983                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1984                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1985                         continue;
1986
1987                 if (prev_dev) {
1988                         skb2 = skb_clone(skb, GFP_ATOMIC);
1989                         if (skb2) {
1990                                 skb2->dev = prev_dev;
1991                                 netif_rx(skb2);
1992                         }
1993                 }
1994
1995                 prev_dev = sdata->dev;
1996                 sdata->dev->stats.rx_packets++;
1997                 sdata->dev->stats.rx_bytes += skb->len;
1998         }
1999
2000         if (prev_dev) {
2001                 skb->dev = prev_dev;
2002                 netif_rx(skb);
2003                 skb = NULL;
2004         } else
2005                 goto out_free_skb;
2006
2007         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2008         return;
2009
2010  out_free_skb:
2011         dev_kfree_skb(skb);
2012 }
2013
2014
2015 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2016                                          struct ieee80211_rx_data *rx,
2017                                          struct sk_buff *skb)
2018 {
2019         ieee80211_rx_result res = RX_DROP_MONITOR;
2020
2021         rx->skb = skb;
2022         rx->sdata = sdata;
2023         rx->dev = sdata->dev;
2024
2025 #define CALL_RXH(rxh)                   \
2026         do {                            \
2027                 res = rxh(rx);          \
2028                 if (res != RX_CONTINUE) \
2029                         goto rxh_done;  \
2030         } while (0);
2031
2032         CALL_RXH(ieee80211_rx_h_passive_scan)
2033         CALL_RXH(ieee80211_rx_h_check)
2034         CALL_RXH(ieee80211_rx_h_decrypt)
2035         CALL_RXH(ieee80211_rx_h_check_more_data)
2036         CALL_RXH(ieee80211_rx_h_sta_process)
2037         CALL_RXH(ieee80211_rx_h_defragment)
2038         CALL_RXH(ieee80211_rx_h_ps_poll)
2039         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2040         /* must be after MMIC verify so header is counted in MPDU mic */
2041         CALL_RXH(ieee80211_rx_h_remove_qos_control)
2042         CALL_RXH(ieee80211_rx_h_amsdu)
2043 #ifdef CONFIG_MAC80211_MESH
2044         if (ieee80211_vif_is_mesh(&sdata->vif))
2045                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2046 #endif
2047         CALL_RXH(ieee80211_rx_h_data)
2048         CALL_RXH(ieee80211_rx_h_ctrl)
2049         CALL_RXH(ieee80211_rx_h_action)
2050         CALL_RXH(ieee80211_rx_h_mgmt)
2051
2052 #undef CALL_RXH
2053
2054  rxh_done:
2055         switch (res) {
2056         case RX_DROP_MONITOR:
2057                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2058                 if (rx->sta)
2059                         rx->sta->rx_dropped++;
2060                 /* fall through */
2061         case RX_CONTINUE:
2062                 ieee80211_rx_cooked_monitor(rx);
2063                 break;
2064         case RX_DROP_UNUSABLE:
2065                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2066                 if (rx->sta)
2067                         rx->sta->rx_dropped++;
2068                 dev_kfree_skb(rx->skb);
2069                 break;
2070         case RX_QUEUED:
2071                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2072                 break;
2073         }
2074 }
2075
2076 /* main receive path */
2077
2078 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2079                                 struct ieee80211_rx_data *rx,
2080                                 struct ieee80211_hdr *hdr)
2081 {
2082         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2083         int multicast = is_multicast_ether_addr(hdr->addr1);
2084
2085         switch (sdata->vif.type) {
2086         case NL80211_IFTYPE_STATION:
2087                 if (!bssid)
2088                         return 0;
2089                 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2090                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2091                                 return 0;
2092                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2093                 } else if (!multicast &&
2094                            compare_ether_addr(sdata->dev->dev_addr,
2095                                               hdr->addr1) != 0) {
2096                         if (!(sdata->dev->flags & IFF_PROMISC))
2097                                 return 0;
2098                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2099                 }
2100                 break;
2101         case NL80211_IFTYPE_ADHOC:
2102                 if (!bssid)
2103                         return 0;
2104                 if (ieee80211_is_beacon(hdr->frame_control)) {
2105                         return 1;
2106                 }
2107                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2108                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2109                                 return 0;
2110                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2111                 } else if (!multicast &&
2112                            compare_ether_addr(sdata->dev->dev_addr,
2113                                               hdr->addr1) != 0) {
2114                         if (!(sdata->dev->flags & IFF_PROMISC))
2115                                 return 0;
2116                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2117                 } else if (!rx->sta) {
2118                         int rate_idx;
2119                         if (rx->status->flag & RX_FLAG_HT)
2120                                 rate_idx = 0; /* TODO: HT rates */
2121                         else
2122                                 rate_idx = rx->status->rate_idx;
2123                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2124                                 BIT(rate_idx));
2125                 }
2126                 break;
2127         case NL80211_IFTYPE_MESH_POINT:
2128                 if (!multicast &&
2129                     compare_ether_addr(sdata->dev->dev_addr,
2130                                        hdr->addr1) != 0) {
2131                         if (!(sdata->dev->flags & IFF_PROMISC))
2132                                 return 0;
2133
2134                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2135                 }
2136                 break;
2137         case NL80211_IFTYPE_AP_VLAN:
2138         case NL80211_IFTYPE_AP:
2139                 if (!bssid) {
2140                         if (compare_ether_addr(sdata->dev->dev_addr,
2141                                                hdr->addr1))
2142                                 return 0;
2143                 } else if (!ieee80211_bssid_match(bssid,
2144                                         sdata->dev->dev_addr)) {
2145                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2146                                 return 0;
2147                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2148                 }
2149                 break;
2150         case NL80211_IFTYPE_WDS:
2151                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2152                         return 0;
2153                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2154                         return 0;
2155                 break;
2156         case NL80211_IFTYPE_MONITOR:
2157                 /* take everything */
2158                 break;
2159         case NL80211_IFTYPE_UNSPECIFIED:
2160         case __NL80211_IFTYPE_AFTER_LAST:
2161                 /* should never get here */
2162                 WARN_ON(1);
2163                 break;
2164         }
2165
2166         return 1;
2167 }
2168
2169 /*
2170  * This is the actual Rx frames handler. as it blongs to Rx path it must
2171  * be called with rcu_read_lock protection.
2172  */
2173 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2174                                          struct sk_buff *skb,
2175                                          struct ieee80211_rx_status *status,
2176                                          struct ieee80211_rate *rate)
2177 {
2178         struct ieee80211_local *local = hw_to_local(hw);
2179         struct ieee80211_sub_if_data *sdata;
2180         struct ieee80211_hdr *hdr;
2181         struct ieee80211_rx_data rx;
2182         int prepares;
2183         struct ieee80211_sub_if_data *prev = NULL;
2184         struct sk_buff *skb_new;
2185
2186         hdr = (struct ieee80211_hdr *)skb->data;
2187         memset(&rx, 0, sizeof(rx));
2188         rx.skb = skb;
2189         rx.local = local;
2190
2191         rx.status = status;
2192         rx.rate = rate;
2193
2194         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2195                 local->dot11ReceivedFragmentCount++;
2196
2197         rx.sta = sta_info_get(local, hdr->addr2);
2198         if (rx.sta) {
2199                 rx.sdata = rx.sta->sdata;
2200                 rx.dev = rx.sta->sdata->dev;
2201         }
2202
2203         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2204                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2205                 return;
2206         }
2207
2208         if (unlikely(local->sw_scanning || local->hw_scanning))
2209                 rx.flags |= IEEE80211_RX_IN_SCAN;
2210
2211         ieee80211_parse_qos(&rx);
2212         ieee80211_verify_alignment(&rx);
2213
2214         skb = rx.skb;
2215
2216         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2217                 if (!netif_running(sdata->dev))
2218                         continue;
2219
2220                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2221                         continue;
2222
2223                 rx.flags |= IEEE80211_RX_RA_MATCH;
2224                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2225
2226                 if (!prepares)
2227                         continue;
2228
2229                 /*
2230                  * frame is destined for this interface, but if it's not
2231                  * also for the previous one we handle that after the
2232                  * loop to avoid copying the SKB once too much
2233                  */
2234
2235                 if (!prev) {
2236                         prev = sdata;
2237                         continue;
2238                 }
2239
2240                 /*
2241                  * frame was destined for the previous interface
2242                  * so invoke RX handlers for it
2243                  */
2244
2245                 skb_new = skb_copy(skb, GFP_ATOMIC);
2246                 if (!skb_new) {
2247                         if (net_ratelimit())
2248                                 printk(KERN_DEBUG "%s: failed to copy "
2249                                        "multicast frame for %s\n",
2250                                        wiphy_name(local->hw.wiphy),
2251                                        prev->dev->name);
2252                         continue;
2253                 }
2254                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2255                 prev = sdata;
2256         }
2257         if (prev)
2258                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2259         else
2260                 dev_kfree_skb(skb);
2261 }
2262
2263 #define SEQ_MODULO 0x1000
2264 #define SEQ_MASK   0xfff
2265
2266 static inline int seq_less(u16 sq1, u16 sq2)
2267 {
2268         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2269 }
2270
2271 static inline u16 seq_inc(u16 sq)
2272 {
2273         return (sq + 1) & SEQ_MASK;
2274 }
2275
2276 static inline u16 seq_sub(u16 sq1, u16 sq2)
2277 {
2278         return (sq1 - sq2) & SEQ_MASK;
2279 }
2280
2281
2282 /*
2283  * As it function blongs to Rx path it must be called with
2284  * the proper rcu_read_lock protection for its flow.
2285  */
2286 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2287                                            struct tid_ampdu_rx *tid_agg_rx,
2288                                            struct sk_buff *skb,
2289                                            u16 mpdu_seq_num,
2290                                            int bar_req)
2291 {
2292         struct ieee80211_local *local = hw_to_local(hw);
2293         struct ieee80211_rx_status status;
2294         u16 head_seq_num, buf_size;
2295         int index;
2296         struct ieee80211_supported_band *sband;
2297         struct ieee80211_rate *rate;
2298
2299         buf_size = tid_agg_rx->buf_size;
2300         head_seq_num = tid_agg_rx->head_seq_num;
2301
2302         /* frame with out of date sequence number */
2303         if (seq_less(mpdu_seq_num, head_seq_num)) {
2304                 dev_kfree_skb(skb);
2305                 return 1;
2306         }
2307
2308         /* if frame sequence number exceeds our buffering window size or
2309          * block Ack Request arrived - release stored frames */
2310         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2311                 /* new head to the ordering buffer */
2312                 if (bar_req)
2313                         head_seq_num = mpdu_seq_num;
2314                 else
2315                         head_seq_num =
2316                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2317                 /* release stored frames up to new head to stack */
2318                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2319                         index = seq_sub(tid_agg_rx->head_seq_num,
2320                                 tid_agg_rx->ssn)
2321                                 % tid_agg_rx->buf_size;
2322
2323                         if (tid_agg_rx->reorder_buf[index]) {
2324                                 /* release the reordered frames to stack */
2325                                 memcpy(&status,
2326                                         tid_agg_rx->reorder_buf[index]->cb,
2327                                         sizeof(status));
2328                                 sband = local->hw.wiphy->bands[status.band];
2329                                 if (status.flag & RX_FLAG_HT) {
2330                                         /* TODO: HT rates */
2331                                         rate = sband->bitrates;
2332                                 } else {
2333                                         rate = &sband->bitrates
2334                                                 [status.rate_idx];
2335                                 }
2336                                 __ieee80211_rx_handle_packet(hw,
2337                                         tid_agg_rx->reorder_buf[index],
2338                                         &status, rate);
2339                                 tid_agg_rx->stored_mpdu_num--;
2340                                 tid_agg_rx->reorder_buf[index] = NULL;
2341                         }
2342                         tid_agg_rx->head_seq_num =
2343                                 seq_inc(tid_agg_rx->head_seq_num);
2344                 }
2345                 if (bar_req)
2346                         return 1;
2347         }
2348
2349         /* now the new frame is always in the range of the reordering */
2350         /* buffer window */
2351         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2352                                 % tid_agg_rx->buf_size;
2353         /* check if we already stored this frame */
2354         if (tid_agg_rx->reorder_buf[index]) {
2355                 dev_kfree_skb(skb);
2356                 return 1;
2357         }
2358
2359         /* if arrived mpdu is in the right order and nothing else stored */
2360         /* release it immediately */
2361         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2362                         tid_agg_rx->stored_mpdu_num == 0) {
2363                 tid_agg_rx->head_seq_num =
2364                         seq_inc(tid_agg_rx->head_seq_num);
2365                 return 0;
2366         }
2367
2368         /* put the frame in the reordering buffer */
2369         tid_agg_rx->reorder_buf[index] = skb;
2370         tid_agg_rx->stored_mpdu_num++;
2371         /* release the buffer until next missing frame */
2372         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2373                                                 % tid_agg_rx->buf_size;
2374         while (tid_agg_rx->reorder_buf[index]) {
2375                 /* release the reordered frame back to stack */
2376                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2377                         sizeof(status));
2378                 sband = local->hw.wiphy->bands[status.band];
2379                 if (status.flag & RX_FLAG_HT)
2380                         rate = sband->bitrates; /* TODO: HT rates */
2381                 else
2382                         rate = &sband->bitrates[status.rate_idx];
2383                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2384                                              &status, rate);
2385                 tid_agg_rx->stored_mpdu_num--;
2386                 tid_agg_rx->reorder_buf[index] = NULL;
2387                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2388                 index = seq_sub(tid_agg_rx->head_seq_num,
2389                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2390         }
2391         return 1;
2392 }
2393
2394 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2395                                      struct sk_buff *skb)
2396 {
2397         struct ieee80211_hw *hw = &local->hw;
2398         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2399         struct sta_info *sta;
2400         struct tid_ampdu_rx *tid_agg_rx;
2401         u16 sc;
2402         u16 mpdu_seq_num;
2403         u8 ret = 0;
2404         int tid;
2405
2406         sta = sta_info_get(local, hdr->addr2);
2407         if (!sta)
2408                 return ret;
2409
2410         /* filter the QoS data rx stream according to
2411          * STA/TID and check if this STA/TID is on aggregation */
2412         if (!ieee80211_is_data_qos(hdr->frame_control))
2413                 goto end_reorder;
2414
2415         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2416
2417         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2418                 goto end_reorder;
2419
2420         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2421
2422         /* qos null data frames are excluded */
2423         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2424                 goto end_reorder;
2425
2426         /* new un-ordered ampdu frame - process it */
2427
2428         /* reset session timer */
2429         if (tid_agg_rx->timeout)
2430                 mod_timer(&tid_agg_rx->session_timer,
2431                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2432
2433         /* if this mpdu is fragmented - terminate rx aggregation session */
2434         sc = le16_to_cpu(hdr->seq_ctrl);
2435         if (sc & IEEE80211_SCTL_FRAG) {
2436                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2437                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2438                 ret = 1;
2439                 goto end_reorder;
2440         }
2441
2442         /* according to mpdu sequence number deal with reordering buffer */
2443         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2444         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2445                                                 mpdu_seq_num, 0);
2446  end_reorder:
2447         return ret;
2448 }
2449
2450 /*
2451  * This is the receive path handler. It is called by a low level driver when an
2452  * 802.11 MPDU is received from the hardware.
2453  */
2454 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2455                     struct ieee80211_rx_status *status)
2456 {
2457         struct ieee80211_local *local = hw_to_local(hw);
2458         struct ieee80211_rate *rate = NULL;
2459         struct ieee80211_supported_band *sband;
2460
2461         if (status->band < 0 ||
2462             status->band >= IEEE80211_NUM_BANDS) {
2463                 WARN_ON(1);
2464                 return;
2465         }
2466
2467         sband = local->hw.wiphy->bands[status->band];
2468         if (!sband) {
2469                 WARN_ON(1);
2470                 return;
2471         }
2472
2473         if (status->flag & RX_FLAG_HT) {
2474                 /* rate_idx is MCS index */
2475                 if (WARN_ON(status->rate_idx < 0 ||
2476                             status->rate_idx >= 76))
2477                         return;
2478                 /* HT rates are not in the table - use the highest legacy rate
2479                  * for now since other parts of mac80211 may not yet be fully
2480                  * MCS aware. */
2481                 rate = &sband->bitrates[sband->n_bitrates - 1];
2482         } else {
2483                 if (WARN_ON(status->rate_idx < 0 ||
2484                             status->rate_idx >= sband->n_bitrates))
2485                         return;
2486                 rate = &sband->bitrates[status->rate_idx];
2487         }
2488
2489         /*
2490          * key references and virtual interfaces are protected using RCU
2491          * and this requires that we are in a read-side RCU section during
2492          * receive processing
2493          */
2494         rcu_read_lock();
2495
2496         /*
2497          * Frames with failed FCS/PLCP checksum are not returned,
2498          * all other frames are returned without radiotap header
2499          * if it was previously present.
2500          * Also, frames with less than 16 bytes are dropped.
2501          */
2502         skb = ieee80211_rx_monitor(local, skb, status, rate);
2503         if (!skb) {
2504                 rcu_read_unlock();
2505                 return;
2506         }
2507
2508         if (!ieee80211_rx_reorder_ampdu(local, skb))
2509                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2510
2511         rcu_read_unlock();
2512 }
2513 EXPORT_SYMBOL(__ieee80211_rx);
2514
2515 /* This is a version of the rx handler that can be called from hard irq
2516  * context. Post the skb on the queue and schedule the tasklet */
2517 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2518                           struct ieee80211_rx_status *status)
2519 {
2520         struct ieee80211_local *local = hw_to_local(hw);
2521
2522         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2523
2524         skb->dev = local->mdev;
2525         /* copy status into skb->cb for use by tasklet */
2526         memcpy(skb->cb, status, sizeof(*status));
2527         skb->pkt_type = IEEE80211_RX_MSG;
2528         skb_queue_tail(&local->skb_queue, skb);
2529         tasklet_schedule(&local->tasklet);
2530 }
2531 EXPORT_SYMBOL(ieee80211_rx_irqsafe);