Merge branch 'devel' into next
[linux-2.6] / 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_DB ||
90             local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
91                 len += 1;
92         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
93                 len += 1;
94
95         if (len & 1) /* padding for RX_FLAGS if necessary */
96                 len++;
97
98         /* make sure radiotap starts at a naturally aligned address */
99         if (len % 8)
100                 len = roundup(len, 8);
101
102         return len;
103 }
104
105 /**
106  * ieee80211_add_rx_radiotap_header - add radiotap header
107  *
108  * add a radiotap header containing all the fields which the hardware provided.
109  */
110 static void
111 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
112                                  struct sk_buff *skb,
113                                  struct ieee80211_rx_status *status,
114                                  struct ieee80211_rate *rate,
115                                  int rtap_len)
116 {
117         struct ieee80211_radiotap_header *rthdr;
118         unsigned char *pos;
119
120         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
121         memset(rthdr, 0, rtap_len);
122
123         /* radiotap header, set always present flags */
124         rthdr->it_present =
125                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
126                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
127                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
128                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
129         rthdr->it_len = cpu_to_le16(rtap_len);
130
131         pos = (unsigned char *)(rthdr+1);
132
133         /* the order of the following fields is important */
134
135         /* IEEE80211_RADIOTAP_TSFT */
136         if (status->flag & RX_FLAG_TSFT) {
137                 *(__le64 *)pos = cpu_to_le64(status->mactime);
138                 rthdr->it_present |=
139                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
140                 pos += 8;
141         }
142
143         /* IEEE80211_RADIOTAP_FLAGS */
144         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
145                 *pos |= IEEE80211_RADIOTAP_F_FCS;
146         if (status->flag & RX_FLAG_SHORTPRE)
147                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
148         pos++;
149
150         /* IEEE80211_RADIOTAP_RATE */
151         if (status->flag & RX_FLAG_HT) {
152                 /*
153                  * TODO: add following information into radiotap header once
154                  * suitable fields are defined for it:
155                  * - MCS index (status->rate_idx)
156                  * - HT40 (status->flag & RX_FLAG_40MHZ)
157                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
158                  */
159                 *pos = 0;
160         } else {
161                 rthdr->it_present |= (1 << IEEE80211_RADIOTAP_RATE);
162                 *pos = rate->bitrate / 5;
163         }
164         pos++;
165
166         /* IEEE80211_RADIOTAP_CHANNEL */
167         *(__le16 *)pos = cpu_to_le16(status->freq);
168         pos += 2;
169         if (status->band == IEEE80211_BAND_5GHZ)
170                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
171                                              IEEE80211_CHAN_5GHZ);
172         else if (rate->flags & IEEE80211_RATE_ERP_G)
173                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
174                                              IEEE80211_CHAN_2GHZ);
175         else
176                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
177                                              IEEE80211_CHAN_2GHZ);
178         pos += 2;
179
180         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
181         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
182                 *pos = status->signal;
183                 rthdr->it_present |=
184                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
185                 pos++;
186         }
187
188         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
189         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
190                 *pos = status->noise;
191                 rthdr->it_present |=
192                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
193                 pos++;
194         }
195
196         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
197
198         /* IEEE80211_RADIOTAP_ANTENNA */
199         *pos = status->antenna;
200         pos++;
201
202         /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
203         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
204                 *pos = status->signal;
205                 rthdr->it_present |=
206                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
207                 pos++;
208         }
209
210         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
211
212         /* IEEE80211_RADIOTAP_RX_FLAGS */
213         /* ensure 2 byte alignment for the 2 byte field as required */
214         if ((pos - (unsigned char *)rthdr) & 1)
215                 pos++;
216         /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
217         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
218                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
219         pos += 2;
220 }
221
222 /*
223  * This function copies a received frame to all monitor interfaces and
224  * returns a cleaned-up SKB that no longer includes the FCS nor the
225  * radiotap header the driver might have added.
226  */
227 static struct sk_buff *
228 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
229                      struct ieee80211_rx_status *status,
230                      struct ieee80211_rate *rate)
231 {
232         struct ieee80211_sub_if_data *sdata;
233         int needed_headroom = 0;
234         struct sk_buff *skb, *skb2;
235         struct net_device *prev_dev = NULL;
236         int present_fcs_len = 0;
237         int rtap_len = 0;
238
239         /*
240          * First, we may need to make a copy of the skb because
241          *  (1) we need to modify it for radiotap (if not present), and
242          *  (2) the other RX handlers will modify the skb we got.
243          *
244          * We don't need to, of course, if we aren't going to return
245          * the SKB because it has a bad FCS/PLCP checksum.
246          */
247         if (status->flag & RX_FLAG_RADIOTAP)
248                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
249         else
250                 /* room for the radiotap header based on driver features */
251                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
252
253         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
254                 present_fcs_len = FCS_LEN;
255
256         if (!local->monitors) {
257                 if (should_drop_frame(status, origskb, present_fcs_len,
258                                       rtap_len)) {
259                         dev_kfree_skb(origskb);
260                         return NULL;
261                 }
262
263                 return remove_monitor_info(local, origskb, rtap_len);
264         }
265
266         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
267                 /* only need to expand headroom if necessary */
268                 skb = origskb;
269                 origskb = NULL;
270
271                 /*
272                  * This shouldn't trigger often because most devices have an
273                  * RX header they pull before we get here, and that should
274                  * be big enough for our radiotap information. We should
275                  * probably export the length to drivers so that we can have
276                  * them allocate enough headroom to start with.
277                  */
278                 if (skb_headroom(skb) < needed_headroom &&
279                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
280                         dev_kfree_skb(skb);
281                         return NULL;
282                 }
283         } else {
284                 /*
285                  * Need to make a copy and possibly remove radiotap header
286                  * and FCS from the original.
287                  */
288                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
289
290                 origskb = remove_monitor_info(local, origskb, rtap_len);
291
292                 if (!skb)
293                         return origskb;
294         }
295
296         /* if necessary, prepend radiotap information */
297         if (!(status->flag & RX_FLAG_RADIOTAP))
298                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
299                                                  needed_headroom);
300
301         skb_reset_mac_header(skb);
302         skb->ip_summed = CHECKSUM_UNNECESSARY;
303         skb->pkt_type = PACKET_OTHERHOST;
304         skb->protocol = htons(ETH_P_802_2);
305
306         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
307                 if (!netif_running(sdata->dev))
308                         continue;
309
310                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
311                         continue;
312
313                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
314                         continue;
315
316                 if (prev_dev) {
317                         skb2 = skb_clone(skb, GFP_ATOMIC);
318                         if (skb2) {
319                                 skb2->dev = prev_dev;
320                                 netif_rx(skb2);
321                         }
322                 }
323
324                 prev_dev = sdata->dev;
325                 sdata->dev->stats.rx_packets++;
326                 sdata->dev->stats.rx_bytes += skb->len;
327         }
328
329         if (prev_dev) {
330                 skb->dev = prev_dev;
331                 netif_rx(skb);
332         } else
333                 dev_kfree_skb(skb);
334
335         return origskb;
336 }
337
338
339 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
340 {
341         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
342         int tid;
343
344         /* does the frame have a qos control field? */
345         if (ieee80211_is_data_qos(hdr->frame_control)) {
346                 u8 *qc = ieee80211_get_qos_ctl(hdr);
347                 /* frame has qos control */
348                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
349                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
350                         rx->flags |= IEEE80211_RX_AMSDU;
351                 else
352                         rx->flags &= ~IEEE80211_RX_AMSDU;
353         } else {
354                 /*
355                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
356                  *
357                  *      Sequence numbers for management frames, QoS data
358                  *      frames with a broadcast/multicast address in the
359                  *      Address 1 field, and all non-QoS data frames sent
360                  *      by QoS STAs are assigned using an additional single
361                  *      modulo-4096 counter, [...]
362                  *
363                  * We also use that counter for non-QoS STAs.
364                  */
365                 tid = NUM_RX_DATA_QUEUES - 1;
366         }
367
368         rx->queue = tid;
369         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
370          * For now, set skb->priority to 0 for other cases. */
371         rx->skb->priority = (tid > 7) ? 0 : tid;
372 }
373
374 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
375 {
376 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
377         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
378         int hdrlen;
379
380         if (!ieee80211_is_data_present(hdr->frame_control))
381                 return;
382
383         /*
384          * Drivers are required to align the payload data in a way that
385          * guarantees that the contained IP header is aligned to a four-
386          * byte boundary. In the case of regular frames, this simply means
387          * aligning the payload to a four-byte boundary (because either
388          * the IP header is directly contained, or IV/RFC1042 headers that
389          * have a length divisible by four are in front of it.
390          *
391          * With A-MSDU frames, however, the payload data address must
392          * yield two modulo four because there are 14-byte 802.3 headers
393          * within the A-MSDU frames that push the IP header further back
394          * to a multiple of four again. Thankfully, the specs were sane
395          * enough this time around to require padding each A-MSDU subframe
396          * to a length that is a multiple of four.
397          *
398          * Padding like atheros hardware adds which is inbetween the 802.11
399          * header and the payload is not supported, the driver is required
400          * to move the 802.11 header further back in that case.
401          */
402         hdrlen = ieee80211_hdrlen(hdr->frame_control);
403         if (rx->flags & IEEE80211_RX_AMSDU)
404                 hdrlen += ETH_HLEN;
405         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
406 #endif
407 }
408
409
410 /* rx handlers */
411
412 static ieee80211_rx_result debug_noinline
413 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
414 {
415         struct ieee80211_local *local = rx->local;
416         struct sk_buff *skb = rx->skb;
417
418         if (unlikely(local->hw_scanning))
419                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
420
421         if (unlikely(local->sw_scanning)) {
422                 /* drop all the other packets during a software scan anyway */
423                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
424                     != RX_QUEUED)
425                         dev_kfree_skb(skb);
426                 return RX_QUEUED;
427         }
428
429         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
430                 /* scanning finished during invoking of handlers */
431                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
432                 return RX_DROP_UNUSABLE;
433         }
434
435         return RX_CONTINUE;
436 }
437
438 static ieee80211_rx_result
439 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
440 {
441         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
442         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
443
444         if (ieee80211_is_data(hdr->frame_control)) {
445                 if (!ieee80211_has_a4(hdr->frame_control))
446                         return RX_DROP_MONITOR;
447                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
448                         return RX_DROP_MONITOR;
449         }
450
451         /* If there is not an established peer link and this is not a peer link
452          * establisment frame, beacon or probe, drop the frame.
453          */
454
455         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
456                 struct ieee80211_mgmt *mgmt;
457
458                 if (!ieee80211_is_mgmt(hdr->frame_control))
459                         return RX_DROP_MONITOR;
460
461                 if (ieee80211_is_action(hdr->frame_control)) {
462                         mgmt = (struct ieee80211_mgmt *)hdr;
463                         if (mgmt->u.action.category != PLINK_CATEGORY)
464                                 return RX_DROP_MONITOR;
465                         return RX_CONTINUE;
466                 }
467
468                 if (ieee80211_is_probe_req(hdr->frame_control) ||
469                     ieee80211_is_probe_resp(hdr->frame_control) ||
470                     ieee80211_is_beacon(hdr->frame_control))
471                         return RX_CONTINUE;
472
473                 return RX_DROP_MONITOR;
474
475         }
476
477 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
478
479         if (ieee80211_is_data(hdr->frame_control) &&
480             is_multicast_ether_addr(hdr->addr1) &&
481             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
482                 return RX_DROP_MONITOR;
483 #undef msh_h_get
484
485         return RX_CONTINUE;
486 }
487
488
489 static ieee80211_rx_result debug_noinline
490 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
491 {
492         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
493
494         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
495         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
496                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
497                              rx->sta->last_seq_ctrl[rx->queue] ==
498                              hdr->seq_ctrl)) {
499                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
500                                 rx->local->dot11FrameDuplicateCount++;
501                                 rx->sta->num_duplicates++;
502                         }
503                         return RX_DROP_MONITOR;
504                 } else
505                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
506         }
507
508         if (unlikely(rx->skb->len < 16)) {
509                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
510                 return RX_DROP_MONITOR;
511         }
512
513         /* Drop disallowed frame classes based on STA auth/assoc state;
514          * IEEE 802.11, Chap 5.5.
515          *
516          * mac80211 filters only based on association state, i.e. it drops
517          * Class 3 frames from not associated stations. hostapd sends
518          * deauth/disassoc frames when needed. In addition, hostapd is
519          * responsible for filtering on both auth and assoc states.
520          */
521
522         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
523                 return ieee80211_rx_mesh_check(rx);
524
525         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
526                       ieee80211_is_pspoll(hdr->frame_control)) &&
527                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
528                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
529                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
530                      !ieee80211_has_tods(hdr->frame_control) &&
531                      ieee80211_is_data(hdr->frame_control)) ||
532                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
533                         /* Drop IBSS frames and frames for other hosts
534                          * silently. */
535                         return RX_DROP_MONITOR;
536                 }
537
538                 return RX_DROP_MONITOR;
539         }
540
541         return RX_CONTINUE;
542 }
543
544
545 static ieee80211_rx_result debug_noinline
546 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
547 {
548         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
549         int keyidx;
550         int hdrlen;
551         ieee80211_rx_result result = RX_DROP_UNUSABLE;
552         struct ieee80211_key *stakey = NULL;
553
554         /*
555          * Key selection 101
556          *
557          * There are three types of keys:
558          *  - GTK (group keys)
559          *  - PTK (pairwise keys)
560          *  - STK (station-to-station pairwise keys)
561          *
562          * When selecting a key, we have to distinguish between multicast
563          * (including broadcast) and unicast frames, the latter can only
564          * use PTKs and STKs while the former always use GTKs. Unless, of
565          * course, actual WEP keys ("pre-RSNA") are used, then unicast
566          * frames can also use key indizes like GTKs. Hence, if we don't
567          * have a PTK/STK we check the key index for a WEP key.
568          *
569          * Note that in a regular BSS, multicast frames are sent by the
570          * AP only, associated stations unicast the frame to the AP first
571          * which then multicasts it on their behalf.
572          *
573          * There is also a slight problem in IBSS mode: GTKs are negotiated
574          * with each station, that is something we don't currently handle.
575          * The spec seems to expect that one negotiates the same key with
576          * every station but there's no such requirement; VLANs could be
577          * possible.
578          */
579
580         if (!ieee80211_has_protected(hdr->frame_control))
581                 return RX_CONTINUE;
582
583         /*
584          * No point in finding a key and decrypting if the frame is neither
585          * addressed to us nor a multicast frame.
586          */
587         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
588                 return RX_CONTINUE;
589
590         if (rx->sta)
591                 stakey = rcu_dereference(rx->sta->key);
592
593         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
594                 rx->key = stakey;
595         } else {
596                 /*
597                  * The device doesn't give us the IV so we won't be
598                  * able to look up the key. That's ok though, we
599                  * don't need to decrypt the frame, we just won't
600                  * be able to keep statistics accurate.
601                  * Except for key threshold notifications, should
602                  * we somehow allow the driver to tell us which key
603                  * the hardware used if this flag is set?
604                  */
605                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
606                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
607                         return RX_CONTINUE;
608
609                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
610
611                 if (rx->skb->len < 8 + hdrlen)
612                         return RX_DROP_UNUSABLE; /* TODO: count this? */
613
614                 /*
615                  * no need to call ieee80211_wep_get_keyidx,
616                  * it verifies a bunch of things we've done already
617                  */
618                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
619
620                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
621
622                 /*
623                  * RSNA-protected unicast frames should always be sent with
624                  * pairwise or station-to-station keys, but for WEP we allow
625                  * using a key index as well.
626                  */
627                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
628                     !is_multicast_ether_addr(hdr->addr1))
629                         rx->key = NULL;
630         }
631
632         if (rx->key) {
633                 rx->key->tx_rx_count++;
634                 /* TODO: add threshold stuff again */
635         } else {
636                 return RX_DROP_MONITOR;
637         }
638
639         /* Check for weak IVs if possible */
640         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
641             ieee80211_is_data(hdr->frame_control) &&
642             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
643              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
644             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
645                 rx->sta->wep_weak_iv_count++;
646
647         switch (rx->key->conf.alg) {
648         case ALG_WEP:
649                 result = ieee80211_crypto_wep_decrypt(rx);
650                 break;
651         case ALG_TKIP:
652                 result = ieee80211_crypto_tkip_decrypt(rx);
653                 break;
654         case ALG_CCMP:
655                 result = ieee80211_crypto_ccmp_decrypt(rx);
656                 break;
657         }
658
659         /* either the frame has been decrypted or will be dropped */
660         rx->status->flag |= RX_FLAG_DECRYPTED;
661
662         return result;
663 }
664
665 static void ap_sta_ps_start(struct sta_info *sta)
666 {
667         struct ieee80211_sub_if_data *sdata = sta->sdata;
668         struct ieee80211_local *local = sdata->local;
669
670         atomic_inc(&sdata->bss->num_sta_ps);
671         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
672         if (local->ops->sta_notify)
673                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
674                                         STA_NOTIFY_SLEEP, &sta->sta);
675 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
676         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
677                sdata->dev->name, sta->sta.addr, sta->sta.aid);
678 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
679 }
680
681 static int ap_sta_ps_end(struct sta_info *sta)
682 {
683         struct ieee80211_sub_if_data *sdata = sta->sdata;
684         struct ieee80211_local *local = sdata->local;
685         struct sk_buff *skb;
686         int sent = 0;
687
688         atomic_dec(&sdata->bss->num_sta_ps);
689
690         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
691         if (local->ops->sta_notify)
692                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
693                                         STA_NOTIFY_AWAKE, &sta->sta);
694
695         if (!skb_queue_empty(&sta->ps_tx_buf))
696                 sta_info_clear_tim_bit(sta);
697
698 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
699         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
700                sdata->dev->name, sta->sta.addr, sta->sta.aid);
701 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
702
703         /* Send all buffered frames to the station */
704         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
705                 sent++;
706                 skb->requeue = 1;
707                 dev_queue_xmit(skb);
708         }
709         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
710                 local->total_ps_buffered--;
711                 sent++;
712 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
713                 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
714                        "since STA not sleeping anymore\n", sdata->dev->name,
715                        sta->sta.addr, sta->sta.aid);
716 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
717                 skb->requeue = 1;
718                 dev_queue_xmit(skb);
719         }
720
721         return sent;
722 }
723
724 static ieee80211_rx_result debug_noinline
725 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
726 {
727         struct sta_info *sta = rx->sta;
728         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
729
730         if (!sta)
731                 return RX_CONTINUE;
732
733         /* Update last_rx only for IBSS packets which are for the current
734          * BSSID to avoid keeping the current IBSS network alive in cases where
735          * other STAs are using different BSSID. */
736         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
737                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
738                                                 NL80211_IFTYPE_ADHOC);
739                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
740                         sta->last_rx = jiffies;
741         } else
742         if (!is_multicast_ether_addr(hdr->addr1) ||
743             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
744                 /* Update last_rx only for unicast frames in order to prevent
745                  * the Probe Request frames (the only broadcast frames from a
746                  * STA in infrastructure mode) from keeping a connection alive.
747                  * Mesh beacons will update last_rx when if they are found to
748                  * match the current local configuration when processed.
749                  */
750                 sta->last_rx = jiffies;
751         }
752
753         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
754                 return RX_CONTINUE;
755
756         sta->rx_fragments++;
757         sta->rx_bytes += rx->skb->len;
758         sta->last_signal = rx->status->signal;
759         sta->last_qual = rx->status->qual;
760         sta->last_noise = rx->status->noise;
761
762         /*
763          * Change STA power saving mode only at the end of a frame
764          * exchange sequence.
765          */
766         if (!ieee80211_has_morefrags(hdr->frame_control) &&
767             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
768              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
769                 if (test_sta_flags(sta, WLAN_STA_PS)) {
770                         /*
771                          * Ignore doze->wake transitions that are
772                          * indicated by non-data frames, the standard
773                          * is unclear here, but for example going to
774                          * PS mode and then scanning would cause a
775                          * doze->wake transition for the probe request,
776                          * and that is clearly undesirable.
777                          */
778                         if (ieee80211_is_data(hdr->frame_control) &&
779                             !ieee80211_has_pm(hdr->frame_control))
780                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
781                 } else {
782                         if (ieee80211_has_pm(hdr->frame_control))
783                                 ap_sta_ps_start(sta);
784                 }
785         }
786
787         /* Drop data::nullfunc frames silently, since they are used only to
788          * control station power saving mode. */
789         if (ieee80211_is_nullfunc(hdr->frame_control)) {
790                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
791                 /* Update counter and free packet here to avoid counting this
792                  * as a dropped packed. */
793                 sta->rx_packets++;
794                 dev_kfree_skb(rx->skb);
795                 return RX_QUEUED;
796         }
797
798         return RX_CONTINUE;
799 } /* ieee80211_rx_h_sta_process */
800
801 static inline struct ieee80211_fragment_entry *
802 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
803                          unsigned int frag, unsigned int seq, int rx_queue,
804                          struct sk_buff **skb)
805 {
806         struct ieee80211_fragment_entry *entry;
807         int idx;
808
809         idx = sdata->fragment_next;
810         entry = &sdata->fragments[sdata->fragment_next++];
811         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
812                 sdata->fragment_next = 0;
813
814         if (!skb_queue_empty(&entry->skb_list)) {
815 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
816                 struct ieee80211_hdr *hdr =
817                         (struct ieee80211_hdr *) entry->skb_list.next->data;
818                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
819                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
820                        "addr1=%pM addr2=%pM\n",
821                        sdata->dev->name, idx,
822                        jiffies - entry->first_frag_time, entry->seq,
823                        entry->last_frag, hdr->addr1, hdr->addr2);
824 #endif
825                 __skb_queue_purge(&entry->skb_list);
826         }
827
828         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
829         *skb = NULL;
830         entry->first_frag_time = jiffies;
831         entry->seq = seq;
832         entry->rx_queue = rx_queue;
833         entry->last_frag = frag;
834         entry->ccmp = 0;
835         entry->extra_len = 0;
836
837         return entry;
838 }
839
840 static inline struct ieee80211_fragment_entry *
841 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
842                           unsigned int frag, unsigned int seq,
843                           int rx_queue, struct ieee80211_hdr *hdr)
844 {
845         struct ieee80211_fragment_entry *entry;
846         int i, idx;
847
848         idx = sdata->fragment_next;
849         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
850                 struct ieee80211_hdr *f_hdr;
851
852                 idx--;
853                 if (idx < 0)
854                         idx = IEEE80211_FRAGMENT_MAX - 1;
855
856                 entry = &sdata->fragments[idx];
857                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
858                     entry->rx_queue != rx_queue ||
859                     entry->last_frag + 1 != frag)
860                         continue;
861
862                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
863
864                 /*
865                  * Check ftype and addresses are equal, else check next fragment
866                  */
867                 if (((hdr->frame_control ^ f_hdr->frame_control) &
868                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
869                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
870                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
871                         continue;
872
873                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
874                         __skb_queue_purge(&entry->skb_list);
875                         continue;
876                 }
877                 return entry;
878         }
879
880         return NULL;
881 }
882
883 static ieee80211_rx_result debug_noinline
884 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
885 {
886         struct ieee80211_hdr *hdr;
887         u16 sc;
888         __le16 fc;
889         unsigned int frag, seq;
890         struct ieee80211_fragment_entry *entry;
891         struct sk_buff *skb;
892
893         hdr = (struct ieee80211_hdr *)rx->skb->data;
894         fc = hdr->frame_control;
895         sc = le16_to_cpu(hdr->seq_ctrl);
896         frag = sc & IEEE80211_SCTL_FRAG;
897
898         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
899                    (rx->skb)->len < 24 ||
900                    is_multicast_ether_addr(hdr->addr1))) {
901                 /* not fragmented */
902                 goto out;
903         }
904         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
905
906         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
907
908         if (frag == 0) {
909                 /* This is the first fragment of a new frame. */
910                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
911                                                  rx->queue, &(rx->skb));
912                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
913                     ieee80211_has_protected(fc)) {
914                         /* Store CCMP PN so that we can verify that the next
915                          * fragment has a sequential PN value. */
916                         entry->ccmp = 1;
917                         memcpy(entry->last_pn,
918                                rx->key->u.ccmp.rx_pn[rx->queue],
919                                CCMP_PN_LEN);
920                 }
921                 return RX_QUEUED;
922         }
923
924         /* This is a fragment for a frame that should already be pending in
925          * fragment cache. Add this fragment to the end of the pending entry.
926          */
927         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
928         if (!entry) {
929                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
930                 return RX_DROP_MONITOR;
931         }
932
933         /* Verify that MPDUs within one MSDU have sequential PN values.
934          * (IEEE 802.11i, 8.3.3.4.5) */
935         if (entry->ccmp) {
936                 int i;
937                 u8 pn[CCMP_PN_LEN], *rpn;
938                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
939                         return RX_DROP_UNUSABLE;
940                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
941                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
942                         pn[i]++;
943                         if (pn[i])
944                                 break;
945                 }
946                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
947                 if (memcmp(pn, rpn, CCMP_PN_LEN))
948                         return RX_DROP_UNUSABLE;
949                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
950         }
951
952         skb_pull(rx->skb, ieee80211_hdrlen(fc));
953         __skb_queue_tail(&entry->skb_list, rx->skb);
954         entry->last_frag = frag;
955         entry->extra_len += rx->skb->len;
956         if (ieee80211_has_morefrags(fc)) {
957                 rx->skb = NULL;
958                 return RX_QUEUED;
959         }
960
961         rx->skb = __skb_dequeue(&entry->skb_list);
962         if (skb_tailroom(rx->skb) < entry->extra_len) {
963                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
964                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
965                                               GFP_ATOMIC))) {
966                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
967                         __skb_queue_purge(&entry->skb_list);
968                         return RX_DROP_UNUSABLE;
969                 }
970         }
971         while ((skb = __skb_dequeue(&entry->skb_list))) {
972                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
973                 dev_kfree_skb(skb);
974         }
975
976         /* Complete frame has been reassembled - process it now */
977         rx->flags |= IEEE80211_RX_FRAGMENTED;
978
979  out:
980         if (rx->sta)
981                 rx->sta->rx_packets++;
982         if (is_multicast_ether_addr(hdr->addr1))
983                 rx->local->dot11MulticastReceivedFrameCount++;
984         else
985                 ieee80211_led_rx(rx->local);
986         return RX_CONTINUE;
987 }
988
989 static ieee80211_rx_result debug_noinline
990 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
991 {
992         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
993         struct sk_buff *skb;
994         int no_pending_pkts;
995         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
996
997         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
998                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
999                 return RX_CONTINUE;
1000
1001         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1002             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1003                 return RX_DROP_UNUSABLE;
1004
1005         skb = skb_dequeue(&rx->sta->tx_filtered);
1006         if (!skb) {
1007                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1008                 if (skb)
1009                         rx->local->total_ps_buffered--;
1010         }
1011         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1012                 skb_queue_empty(&rx->sta->ps_tx_buf);
1013
1014         if (skb) {
1015                 struct ieee80211_hdr *hdr =
1016                         (struct ieee80211_hdr *) skb->data;
1017
1018                 /*
1019                  * Tell TX path to send one frame even though the STA may
1020                  * still remain is PS mode after this frame exchange.
1021                  */
1022                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1023
1024 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1025                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1026                        rx->sta->sta.addr, rx->sta->sta.aid,
1027                        skb_queue_len(&rx->sta->ps_tx_buf));
1028 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1029
1030                 /* Use MoreData flag to indicate whether there are more
1031                  * buffered frames for this STA */
1032                 if (no_pending_pkts)
1033                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1034                 else
1035                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1036
1037                 dev_queue_xmit(skb);
1038
1039                 if (no_pending_pkts)
1040                         sta_info_clear_tim_bit(rx->sta);
1041 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1042         } else if (!rx->sent_ps_buffered) {
1043                 /*
1044                  * FIXME: This can be the result of a race condition between
1045                  *        us expiring a frame and the station polling for it.
1046                  *        Should we send it a null-func frame indicating we
1047                  *        have nothing buffered for it?
1048                  */
1049                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1050                        "though there are no buffered frames for it\n",
1051                        rx->dev->name, rx->sta->sta.addr);
1052 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1053         }
1054
1055         /* Free PS Poll skb here instead of returning RX_DROP that would
1056          * count as an dropped frame. */
1057         dev_kfree_skb(rx->skb);
1058
1059         return RX_QUEUED;
1060 }
1061
1062 static ieee80211_rx_result debug_noinline
1063 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1064 {
1065         u8 *data = rx->skb->data;
1066         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1067
1068         if (!ieee80211_is_data_qos(hdr->frame_control))
1069                 return RX_CONTINUE;
1070
1071         /* remove the qos control field, update frame type and meta-data */
1072         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1073                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1074         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1075         /* change frame type to non QOS */
1076         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1077
1078         return RX_CONTINUE;
1079 }
1080
1081 static int
1082 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1083 {
1084         if (unlikely(!rx->sta ||
1085             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1086                 return -EACCES;
1087
1088         return 0;
1089 }
1090
1091 static int
1092 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1093 {
1094         /*
1095          * Pass through unencrypted frames if the hardware has
1096          * decrypted them already.
1097          */
1098         if (rx->status->flag & RX_FLAG_DECRYPTED)
1099                 return 0;
1100
1101         /* Drop unencrypted frames if key is set. */
1102         if (unlikely(!ieee80211_has_protected(fc) &&
1103                      !ieee80211_is_nullfunc(fc) &&
1104                      (rx->key || rx->sdata->drop_unencrypted)))
1105                 return -EACCES;
1106
1107         return 0;
1108 }
1109
1110 static int
1111 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1112 {
1113         struct net_device *dev = rx->dev;
1114         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1115         u16 hdrlen, ethertype;
1116         u8 *payload;
1117         u8 dst[ETH_ALEN];
1118         u8 src[ETH_ALEN] __aligned(2);
1119         struct sk_buff *skb = rx->skb;
1120         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1121
1122         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1123                 return -1;
1124
1125         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1126
1127         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1128          * header
1129          * IEEE 802.11 address fields:
1130          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1131          *   0     0   DA    SA    BSSID n/a
1132          *   0     1   DA    BSSID SA    n/a
1133          *   1     0   BSSID SA    DA    n/a
1134          *   1     1   RA    TA    DA    SA
1135          */
1136         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1137         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1138
1139         switch (hdr->frame_control &
1140                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1141         case __constant_cpu_to_le16(IEEE80211_FCTL_TODS):
1142                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1143                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1144                         return -1;
1145                 break;
1146         case __constant_cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1147                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1148                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1149                         return -1;
1150                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1151                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1152                                 (skb->data + hdrlen);
1153                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1154                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1155                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1156                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1157                         }
1158                 }
1159                 break;
1160         case __constant_cpu_to_le16(IEEE80211_FCTL_FROMDS):
1161                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1162                     (is_multicast_ether_addr(dst) &&
1163                      !compare_ether_addr(src, dev->dev_addr)))
1164                         return -1;
1165                 break;
1166         case __constant_cpu_to_le16(0):
1167                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1168                         return -1;
1169                 break;
1170         }
1171
1172         if (unlikely(skb->len - hdrlen < 8))
1173                 return -1;
1174
1175         payload = skb->data + hdrlen;
1176         ethertype = (payload[6] << 8) | payload[7];
1177
1178         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1179                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1180                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1181                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1182                  * replace EtherType */
1183                 skb_pull(skb, hdrlen + 6);
1184                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1185                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1186         } else {
1187                 struct ethhdr *ehdr;
1188                 __be16 len;
1189
1190                 skb_pull(skb, hdrlen);
1191                 len = htons(skb->len);
1192                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1193                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1194                 memcpy(ehdr->h_source, src, ETH_ALEN);
1195                 ehdr->h_proto = len;
1196         }
1197         return 0;
1198 }
1199
1200 /*
1201  * requires that rx->skb is a frame with ethernet header
1202  */
1203 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1204 {
1205         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1206                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1207         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1208
1209         /*
1210          * Allow EAPOL frames to us/the PAE group address regardless
1211          * of whether the frame was encrypted or not.
1212          */
1213         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1214             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1215              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1216                 return true;
1217
1218         if (ieee80211_802_1x_port_control(rx) ||
1219             ieee80211_drop_unencrypted(rx, fc))
1220                 return false;
1221
1222         return true;
1223 }
1224
1225 /*
1226  * requires that rx->skb is a frame with ethernet header
1227  */
1228 static void
1229 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1230 {
1231         struct net_device *dev = rx->dev;
1232         struct ieee80211_local *local = rx->local;
1233         struct sk_buff *skb, *xmit_skb;
1234         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1235         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1236         struct sta_info *dsta;
1237
1238         skb = rx->skb;
1239         xmit_skb = NULL;
1240
1241         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1242              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1243             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1244             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1245                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1246                         /*
1247                          * send multicast frames both to higher layers in
1248                          * local net stack and back to the wireless medium
1249                          */
1250                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1251                         if (!xmit_skb && net_ratelimit())
1252                                 printk(KERN_DEBUG "%s: failed to clone "
1253                                        "multicast frame\n", dev->name);
1254                 } else {
1255                         dsta = sta_info_get(local, skb->data);
1256                         if (dsta && dsta->sdata->dev == dev) {
1257                                 /*
1258                                  * The destination station is associated to
1259                                  * this AP (in this VLAN), so send the frame
1260                                  * directly to it and do not pass it to local
1261                                  * net stack.
1262                                  */
1263                                 xmit_skb = skb;
1264                                 skb = NULL;
1265                         }
1266                 }
1267         }
1268
1269         if (skb) {
1270                 /* deliver to local stack */
1271                 skb->protocol = eth_type_trans(skb, dev);
1272                 memset(skb->cb, 0, sizeof(skb->cb));
1273                 netif_rx(skb);
1274         }
1275
1276         if (xmit_skb) {
1277                 /* send to wireless media */
1278                 xmit_skb->protocol = htons(ETH_P_802_3);
1279                 skb_reset_network_header(xmit_skb);
1280                 skb_reset_mac_header(xmit_skb);
1281                 dev_queue_xmit(xmit_skb);
1282         }
1283 }
1284
1285 static ieee80211_rx_result debug_noinline
1286 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1287 {
1288         struct net_device *dev = rx->dev;
1289         struct ieee80211_local *local = rx->local;
1290         u16 ethertype;
1291         u8 *payload;
1292         struct sk_buff *skb = rx->skb, *frame = NULL;
1293         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1294         __le16 fc = hdr->frame_control;
1295         const struct ethhdr *eth;
1296         int remaining, err;
1297         u8 dst[ETH_ALEN];
1298         u8 src[ETH_ALEN];
1299
1300         if (unlikely(!ieee80211_is_data(fc)))
1301                 return RX_CONTINUE;
1302
1303         if (unlikely(!ieee80211_is_data_present(fc)))
1304                 return RX_DROP_MONITOR;
1305
1306         if (!(rx->flags & IEEE80211_RX_AMSDU))
1307                 return RX_CONTINUE;
1308
1309         err = ieee80211_data_to_8023(rx);
1310         if (unlikely(err))
1311                 return RX_DROP_UNUSABLE;
1312
1313         skb->dev = dev;
1314
1315         dev->stats.rx_packets++;
1316         dev->stats.rx_bytes += skb->len;
1317
1318         /* skip the wrapping header */
1319         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1320         if (!eth)
1321                 return RX_DROP_UNUSABLE;
1322
1323         while (skb != frame) {
1324                 u8 padding;
1325                 __be16 len = eth->h_proto;
1326                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1327
1328                 remaining = skb->len;
1329                 memcpy(dst, eth->h_dest, ETH_ALEN);
1330                 memcpy(src, eth->h_source, ETH_ALEN);
1331
1332                 padding = ((4 - subframe_len) & 0x3);
1333                 /* the last MSDU has no padding */
1334                 if (subframe_len > remaining)
1335                         return RX_DROP_UNUSABLE;
1336
1337                 skb_pull(skb, sizeof(struct ethhdr));
1338                 /* if last subframe reuse skb */
1339                 if (remaining <= subframe_len + padding)
1340                         frame = skb;
1341                 else {
1342                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1343                                               subframe_len);
1344
1345                         if (frame == NULL)
1346                                 return RX_DROP_UNUSABLE;
1347
1348                         skb_reserve(frame, local->hw.extra_tx_headroom +
1349                                     sizeof(struct ethhdr));
1350                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1351                                 ntohs(len));
1352
1353                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1354                                                         padding);
1355                         if (!eth) {
1356                                 dev_kfree_skb(frame);
1357                                 return RX_DROP_UNUSABLE;
1358                         }
1359                 }
1360
1361                 skb_reset_network_header(frame);
1362                 frame->dev = dev;
1363                 frame->priority = skb->priority;
1364                 rx->skb = frame;
1365
1366                 payload = frame->data;
1367                 ethertype = (payload[6] << 8) | payload[7];
1368
1369                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1370                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1371                            compare_ether_addr(payload,
1372                                               bridge_tunnel_header) == 0)) {
1373                         /* remove RFC1042 or Bridge-Tunnel
1374                          * encapsulation and replace EtherType */
1375                         skb_pull(frame, 6);
1376                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1377                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1378                 } else {
1379                         memcpy(skb_push(frame, sizeof(__be16)),
1380                                &len, sizeof(__be16));
1381                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1382                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1383                 }
1384
1385                 if (!ieee80211_frame_allowed(rx, fc)) {
1386                         if (skb == frame) /* last frame */
1387                                 return RX_DROP_UNUSABLE;
1388                         dev_kfree_skb(frame);
1389                         continue;
1390                 }
1391
1392                 ieee80211_deliver_skb(rx);
1393         }
1394
1395         return RX_QUEUED;
1396 }
1397
1398 #ifdef CONFIG_MAC80211_MESH
1399 static ieee80211_rx_result
1400 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1401 {
1402         struct ieee80211_hdr *hdr;
1403         struct ieee80211s_hdr *mesh_hdr;
1404         unsigned int hdrlen;
1405         struct sk_buff *skb = rx->skb, *fwd_skb;
1406
1407         hdr = (struct ieee80211_hdr *) skb->data;
1408         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1409         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1410
1411         if (!ieee80211_is_data(hdr->frame_control))
1412                 return RX_CONTINUE;
1413
1414         if (!mesh_hdr->ttl)
1415                 /* illegal frame */
1416                 return RX_DROP_MONITOR;
1417
1418         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1419                 struct ieee80211_sub_if_data *sdata;
1420                 struct mesh_path *mppath;
1421
1422                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1423                 rcu_read_lock();
1424                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1425                 if (!mppath) {
1426                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1427                 } else {
1428                         spin_lock_bh(&mppath->state_lock);
1429                         mppath->exp_time = jiffies;
1430                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1431                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1432                         spin_unlock_bh(&mppath->state_lock);
1433                 }
1434                 rcu_read_unlock();
1435         }
1436
1437         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1438                 return RX_CONTINUE;
1439
1440         mesh_hdr->ttl--;
1441
1442         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1443                 if (!mesh_hdr->ttl)
1444                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1445                                                      dropped_frames_ttl);
1446                 else {
1447                         struct ieee80211_hdr *fwd_hdr;
1448                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1449
1450                         if (!fwd_skb && net_ratelimit())
1451                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1452                                                    rx->dev->name);
1453
1454                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1455                         /*
1456                          * Save TA to addr1 to send TA a path error if a
1457                          * suitable next hop is not found
1458                          */
1459                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1460                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1461                         fwd_skb->dev = rx->local->mdev;
1462                         fwd_skb->iif = rx->dev->ifindex;
1463                         dev_queue_xmit(fwd_skb);
1464                 }
1465         }
1466
1467         if (is_multicast_ether_addr(hdr->addr3) ||
1468             rx->dev->flags & IFF_PROMISC)
1469                 return RX_CONTINUE;
1470         else
1471                 return RX_DROP_MONITOR;
1472 }
1473 #endif
1474
1475 static ieee80211_rx_result debug_noinline
1476 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1477 {
1478         struct net_device *dev = rx->dev;
1479         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1480         __le16 fc = hdr->frame_control;
1481         int err;
1482
1483         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1484                 return RX_CONTINUE;
1485
1486         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1487                 return RX_DROP_MONITOR;
1488
1489         err = ieee80211_data_to_8023(rx);
1490         if (unlikely(err))
1491                 return RX_DROP_UNUSABLE;
1492
1493         if (!ieee80211_frame_allowed(rx, fc))
1494                 return RX_DROP_MONITOR;
1495
1496         rx->skb->dev = dev;
1497
1498         dev->stats.rx_packets++;
1499         dev->stats.rx_bytes += rx->skb->len;
1500
1501         ieee80211_deliver_skb(rx);
1502
1503         return RX_QUEUED;
1504 }
1505
1506 static ieee80211_rx_result debug_noinline
1507 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1508 {
1509         struct ieee80211_local *local = rx->local;
1510         struct ieee80211_hw *hw = &local->hw;
1511         struct sk_buff *skb = rx->skb;
1512         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1513         struct tid_ampdu_rx *tid_agg_rx;
1514         u16 start_seq_num;
1515         u16 tid;
1516
1517         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1518                 return RX_CONTINUE;
1519
1520         if (ieee80211_is_back_req(bar->frame_control)) {
1521                 if (!rx->sta)
1522                         return RX_CONTINUE;
1523                 tid = le16_to_cpu(bar->control) >> 12;
1524                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1525                                         != HT_AGG_STATE_OPERATIONAL)
1526                         return RX_CONTINUE;
1527                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1528
1529                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1530
1531                 /* reset session timer */
1532                 if (tid_agg_rx->timeout) {
1533                         unsigned long expires =
1534                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1535                         mod_timer(&tid_agg_rx->session_timer, expires);
1536                 }
1537
1538                 /* manage reordering buffer according to requested */
1539                 /* sequence number */
1540                 rcu_read_lock();
1541                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1542                                                  start_seq_num, 1);
1543                 rcu_read_unlock();
1544                 return RX_DROP_UNUSABLE;
1545         }
1546
1547         return RX_CONTINUE;
1548 }
1549
1550 static ieee80211_rx_result debug_noinline
1551 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1552 {
1553         struct ieee80211_local *local = rx->local;
1554         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1555         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1556         int len = rx->skb->len;
1557
1558         if (!ieee80211_is_action(mgmt->frame_control))
1559                 return RX_CONTINUE;
1560
1561         if (!rx->sta)
1562                 return RX_DROP_MONITOR;
1563
1564         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1565                 return RX_DROP_MONITOR;
1566
1567         /* all categories we currently handle have action_code */
1568         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1569                 return RX_DROP_MONITOR;
1570
1571         switch (mgmt->u.action.category) {
1572         case WLAN_CATEGORY_BACK:
1573                 switch (mgmt->u.action.u.addba_req.action_code) {
1574                 case WLAN_ACTION_ADDBA_REQ:
1575                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1576                                    sizeof(mgmt->u.action.u.addba_req)))
1577                                 return RX_DROP_MONITOR;
1578                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1579                         break;
1580                 case WLAN_ACTION_ADDBA_RESP:
1581                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1582                                    sizeof(mgmt->u.action.u.addba_resp)))
1583                                 return RX_DROP_MONITOR;
1584                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1585                         break;
1586                 case WLAN_ACTION_DELBA:
1587                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1588                                    sizeof(mgmt->u.action.u.delba)))
1589                                 return RX_DROP_MONITOR;
1590                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1591                         break;
1592                 }
1593                 break;
1594         case WLAN_CATEGORY_SPECTRUM_MGMT:
1595                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1596                         return RX_DROP_MONITOR;
1597                 switch (mgmt->u.action.u.measurement.action_code) {
1598                 case WLAN_ACTION_SPCT_MSR_REQ:
1599                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1600                                    sizeof(mgmt->u.action.u.measurement)))
1601                                 return RX_DROP_MONITOR;
1602                         ieee80211_process_measurement_req(sdata, mgmt, len);
1603                         break;
1604                 }
1605                 break;
1606         default:
1607                 return RX_CONTINUE;
1608         }
1609
1610         rx->sta->rx_packets++;
1611         dev_kfree_skb(rx->skb);
1612         return RX_QUEUED;
1613 }
1614
1615 static ieee80211_rx_result debug_noinline
1616 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1617 {
1618         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1619
1620         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1621                 return RX_DROP_MONITOR;
1622
1623         if (ieee80211_vif_is_mesh(&sdata->vif))
1624                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1625
1626         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1627             sdata->vif.type != NL80211_IFTYPE_ADHOC)
1628                 return RX_DROP_MONITOR;
1629
1630         if (sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)
1631                 return RX_DROP_MONITOR;
1632
1633         ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1634         return RX_QUEUED;
1635 }
1636
1637 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1638                                             struct ieee80211_hdr *hdr,
1639                                             struct ieee80211_rx_data *rx)
1640 {
1641         int keyidx;
1642         unsigned int hdrlen;
1643
1644         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1645         if (rx->skb->len >= hdrlen + 4)
1646                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1647         else
1648                 keyidx = -1;
1649
1650         if (!rx->sta) {
1651                 /*
1652                  * Some hardware seem to generate incorrect Michael MIC
1653                  * reports; ignore them to avoid triggering countermeasures.
1654                  */
1655                 goto ignore;
1656         }
1657
1658         if (!ieee80211_has_protected(hdr->frame_control))
1659                 goto ignore;
1660
1661         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1662                 /*
1663                  * APs with pairwise keys should never receive Michael MIC
1664                  * errors for non-zero keyidx because these are reserved for
1665                  * group keys and only the AP is sending real multicast
1666                  * frames in the BSS.
1667                  */
1668                 goto ignore;
1669         }
1670
1671         if (!ieee80211_is_data(hdr->frame_control) &&
1672             !ieee80211_is_auth(hdr->frame_control))
1673                 goto ignore;
1674
1675         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1676  ignore:
1677         dev_kfree_skb(rx->skb);
1678         rx->skb = NULL;
1679 }
1680
1681 /* TODO: use IEEE80211_RX_FRAGMENTED */
1682 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1683 {
1684         struct ieee80211_sub_if_data *sdata;
1685         struct ieee80211_local *local = rx->local;
1686         struct ieee80211_rtap_hdr {
1687                 struct ieee80211_radiotap_header hdr;
1688                 u8 flags;
1689                 u8 rate;
1690                 __le16 chan_freq;
1691                 __le16 chan_flags;
1692         } __attribute__ ((packed)) *rthdr;
1693         struct sk_buff *skb = rx->skb, *skb2;
1694         struct net_device *prev_dev = NULL;
1695         struct ieee80211_rx_status *status = rx->status;
1696
1697         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1698                 goto out_free_skb;
1699
1700         if (skb_headroom(skb) < sizeof(*rthdr) &&
1701             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1702                 goto out_free_skb;
1703
1704         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1705         memset(rthdr, 0, sizeof(*rthdr));
1706         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1707         rthdr->hdr.it_present =
1708                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1709                             (1 << IEEE80211_RADIOTAP_RATE) |
1710                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1711
1712         rthdr->rate = rx->rate->bitrate / 5;
1713         rthdr->chan_freq = cpu_to_le16(status->freq);
1714
1715         if (status->band == IEEE80211_BAND_5GHZ)
1716                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1717                                                 IEEE80211_CHAN_5GHZ);
1718         else
1719                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1720                                                 IEEE80211_CHAN_2GHZ);
1721
1722         skb_set_mac_header(skb, 0);
1723         skb->ip_summed = CHECKSUM_UNNECESSARY;
1724         skb->pkt_type = PACKET_OTHERHOST;
1725         skb->protocol = htons(ETH_P_802_2);
1726
1727         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1728                 if (!netif_running(sdata->dev))
1729                         continue;
1730
1731                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1732                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1733                         continue;
1734
1735                 if (prev_dev) {
1736                         skb2 = skb_clone(skb, GFP_ATOMIC);
1737                         if (skb2) {
1738                                 skb2->dev = prev_dev;
1739                                 netif_rx(skb2);
1740                         }
1741                 }
1742
1743                 prev_dev = sdata->dev;
1744                 sdata->dev->stats.rx_packets++;
1745                 sdata->dev->stats.rx_bytes += skb->len;
1746         }
1747
1748         if (prev_dev) {
1749                 skb->dev = prev_dev;
1750                 netif_rx(skb);
1751                 skb = NULL;
1752         } else
1753                 goto out_free_skb;
1754
1755         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1756         return;
1757
1758  out_free_skb:
1759         dev_kfree_skb(skb);
1760 }
1761
1762
1763 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1764                                          struct ieee80211_rx_data *rx,
1765                                          struct sk_buff *skb)
1766 {
1767         ieee80211_rx_result res = RX_DROP_MONITOR;
1768
1769         rx->skb = skb;
1770         rx->sdata = sdata;
1771         rx->dev = sdata->dev;
1772
1773 #define CALL_RXH(rxh)                   \
1774         do {                            \
1775                 res = rxh(rx);          \
1776                 if (res != RX_CONTINUE) \
1777                         goto rxh_done;  \
1778         } while (0);
1779
1780         CALL_RXH(ieee80211_rx_h_passive_scan)
1781         CALL_RXH(ieee80211_rx_h_check)
1782         CALL_RXH(ieee80211_rx_h_decrypt)
1783         CALL_RXH(ieee80211_rx_h_sta_process)
1784         CALL_RXH(ieee80211_rx_h_defragment)
1785         CALL_RXH(ieee80211_rx_h_ps_poll)
1786         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1787         /* must be after MMIC verify so header is counted in MPDU mic */
1788         CALL_RXH(ieee80211_rx_h_remove_qos_control)
1789         CALL_RXH(ieee80211_rx_h_amsdu)
1790 #ifdef CONFIG_MAC80211_MESH
1791         if (ieee80211_vif_is_mesh(&sdata->vif))
1792                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
1793 #endif
1794         CALL_RXH(ieee80211_rx_h_data)
1795         CALL_RXH(ieee80211_rx_h_ctrl)
1796         CALL_RXH(ieee80211_rx_h_action)
1797         CALL_RXH(ieee80211_rx_h_mgmt)
1798
1799 #undef CALL_RXH
1800
1801  rxh_done:
1802         switch (res) {
1803         case RX_DROP_MONITOR:
1804                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1805                 if (rx->sta)
1806                         rx->sta->rx_dropped++;
1807                 /* fall through */
1808         case RX_CONTINUE:
1809                 ieee80211_rx_cooked_monitor(rx);
1810                 break;
1811         case RX_DROP_UNUSABLE:
1812                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1813                 if (rx->sta)
1814                         rx->sta->rx_dropped++;
1815                 dev_kfree_skb(rx->skb);
1816                 break;
1817         case RX_QUEUED:
1818                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1819                 break;
1820         }
1821 }
1822
1823 /* main receive path */
1824
1825 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1826                                 u8 *bssid, struct ieee80211_rx_data *rx,
1827                                 struct ieee80211_hdr *hdr)
1828 {
1829         int multicast = is_multicast_ether_addr(hdr->addr1);
1830
1831         switch (sdata->vif.type) {
1832         case NL80211_IFTYPE_STATION:
1833                 if (!bssid)
1834                         return 0;
1835                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1836                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1837                                 return 0;
1838                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1839                 } else if (!multicast &&
1840                            compare_ether_addr(sdata->dev->dev_addr,
1841                                               hdr->addr1) != 0) {
1842                         if (!(sdata->dev->flags & IFF_PROMISC))
1843                                 return 0;
1844                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1845                 }
1846                 break;
1847         case NL80211_IFTYPE_ADHOC:
1848                 if (!bssid)
1849                         return 0;
1850                 if (ieee80211_is_beacon(hdr->frame_control)) {
1851                         return 1;
1852                 }
1853                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1854                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1855                                 return 0;
1856                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1857                 } else if (!multicast &&
1858                            compare_ether_addr(sdata->dev->dev_addr,
1859                                               hdr->addr1) != 0) {
1860                         if (!(sdata->dev->flags & IFF_PROMISC))
1861                                 return 0;
1862                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1863                 } else if (!rx->sta) {
1864                         int rate_idx;
1865                         if (rx->status->flag & RX_FLAG_HT)
1866                                 rate_idx = 0; /* TODO: HT rates */
1867                         else
1868                                 rate_idx = rx->status->rate_idx;
1869                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
1870                                 BIT(rate_idx));
1871                 }
1872                 break;
1873         case NL80211_IFTYPE_MESH_POINT:
1874                 if (!multicast &&
1875                     compare_ether_addr(sdata->dev->dev_addr,
1876                                        hdr->addr1) != 0) {
1877                         if (!(sdata->dev->flags & IFF_PROMISC))
1878                                 return 0;
1879
1880                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1881                 }
1882                 break;
1883         case NL80211_IFTYPE_AP_VLAN:
1884         case NL80211_IFTYPE_AP:
1885                 if (!bssid) {
1886                         if (compare_ether_addr(sdata->dev->dev_addr,
1887                                                hdr->addr1))
1888                                 return 0;
1889                 } else if (!ieee80211_bssid_match(bssid,
1890                                         sdata->dev->dev_addr)) {
1891                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1892                                 return 0;
1893                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1894                 }
1895                 break;
1896         case NL80211_IFTYPE_WDS:
1897                 if (bssid || !ieee80211_is_data(hdr->frame_control))
1898                         return 0;
1899                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1900                         return 0;
1901                 break;
1902         case NL80211_IFTYPE_MONITOR:
1903                 /* take everything */
1904                 break;
1905         case NL80211_IFTYPE_UNSPECIFIED:
1906         case __NL80211_IFTYPE_AFTER_LAST:
1907                 /* should never get here */
1908                 WARN_ON(1);
1909                 break;
1910         }
1911
1912         return 1;
1913 }
1914
1915 /*
1916  * This is the actual Rx frames handler. as it blongs to Rx path it must
1917  * be called with rcu_read_lock protection.
1918  */
1919 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1920                                          struct sk_buff *skb,
1921                                          struct ieee80211_rx_status *status,
1922                                          struct ieee80211_rate *rate)
1923 {
1924         struct ieee80211_local *local = hw_to_local(hw);
1925         struct ieee80211_sub_if_data *sdata;
1926         struct ieee80211_hdr *hdr;
1927         struct ieee80211_rx_data rx;
1928         int prepares;
1929         struct ieee80211_sub_if_data *prev = NULL;
1930         struct sk_buff *skb_new;
1931         u8 *bssid;
1932
1933         hdr = (struct ieee80211_hdr *)skb->data;
1934         memset(&rx, 0, sizeof(rx));
1935         rx.skb = skb;
1936         rx.local = local;
1937
1938         rx.status = status;
1939         rx.rate = rate;
1940
1941         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
1942                 local->dot11ReceivedFragmentCount++;
1943
1944         rx.sta = sta_info_get(local, hdr->addr2);
1945         if (rx.sta) {
1946                 rx.sdata = rx.sta->sdata;
1947                 rx.dev = rx.sta->sdata->dev;
1948         }
1949
1950         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1951                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1952                 return;
1953         }
1954
1955         if (unlikely(local->sw_scanning || local->hw_scanning))
1956                 rx.flags |= IEEE80211_RX_IN_SCAN;
1957
1958         ieee80211_parse_qos(&rx);
1959         ieee80211_verify_ip_alignment(&rx);
1960
1961         skb = rx.skb;
1962
1963         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1964                 if (!netif_running(sdata->dev))
1965                         continue;
1966
1967                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
1968                         continue;
1969
1970                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1971                 rx.flags |= IEEE80211_RX_RA_MATCH;
1972                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1973
1974                 if (!prepares)
1975                         continue;
1976
1977                 /*
1978                  * frame is destined for this interface, but if it's not
1979                  * also for the previous one we handle that after the
1980                  * loop to avoid copying the SKB once too much
1981                  */
1982
1983                 if (!prev) {
1984                         prev = sdata;
1985                         continue;
1986                 }
1987
1988                 /*
1989                  * frame was destined for the previous interface
1990                  * so invoke RX handlers for it
1991                  */
1992
1993                 skb_new = skb_copy(skb, GFP_ATOMIC);
1994                 if (!skb_new) {
1995                         if (net_ratelimit())
1996                                 printk(KERN_DEBUG "%s: failed to copy "
1997                                        "multicast frame for %s\n",
1998                                        wiphy_name(local->hw.wiphy),
1999                                        prev->dev->name);
2000                         continue;
2001                 }
2002                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2003                 prev = sdata;
2004         }
2005         if (prev)
2006                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2007         else
2008                 dev_kfree_skb(skb);
2009 }
2010
2011 #define SEQ_MODULO 0x1000
2012 #define SEQ_MASK   0xfff
2013
2014 static inline int seq_less(u16 sq1, u16 sq2)
2015 {
2016         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2017 }
2018
2019 static inline u16 seq_inc(u16 sq)
2020 {
2021         return (sq + 1) & SEQ_MASK;
2022 }
2023
2024 static inline u16 seq_sub(u16 sq1, u16 sq2)
2025 {
2026         return (sq1 - sq2) & SEQ_MASK;
2027 }
2028
2029
2030 /*
2031  * As it function blongs to Rx path it must be called with
2032  * the proper rcu_read_lock protection for its flow.
2033  */
2034 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2035                                            struct tid_ampdu_rx *tid_agg_rx,
2036                                            struct sk_buff *skb,
2037                                            u16 mpdu_seq_num,
2038                                            int bar_req)
2039 {
2040         struct ieee80211_local *local = hw_to_local(hw);
2041         struct ieee80211_rx_status status;
2042         u16 head_seq_num, buf_size;
2043         int index;
2044         struct ieee80211_supported_band *sband;
2045         struct ieee80211_rate *rate;
2046
2047         buf_size = tid_agg_rx->buf_size;
2048         head_seq_num = tid_agg_rx->head_seq_num;
2049
2050         /* frame with out of date sequence number */
2051         if (seq_less(mpdu_seq_num, head_seq_num)) {
2052                 dev_kfree_skb(skb);
2053                 return 1;
2054         }
2055
2056         /* if frame sequence number exceeds our buffering window size or
2057          * block Ack Request arrived - release stored frames */
2058         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2059                 /* new head to the ordering buffer */
2060                 if (bar_req)
2061                         head_seq_num = mpdu_seq_num;
2062                 else
2063                         head_seq_num =
2064                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2065                 /* release stored frames up to new head to stack */
2066                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2067                         index = seq_sub(tid_agg_rx->head_seq_num,
2068                                 tid_agg_rx->ssn)
2069                                 % tid_agg_rx->buf_size;
2070
2071                         if (tid_agg_rx->reorder_buf[index]) {
2072                                 /* release the reordered frames to stack */
2073                                 memcpy(&status,
2074                                         tid_agg_rx->reorder_buf[index]->cb,
2075                                         sizeof(status));
2076                                 sband = local->hw.wiphy->bands[status.band];
2077                                 if (status.flag & RX_FLAG_HT) {
2078                                         /* TODO: HT rates */
2079                                         rate = sband->bitrates;
2080                                 } else {
2081                                         rate = &sband->bitrates
2082                                                 [status.rate_idx];
2083                                 }
2084                                 __ieee80211_rx_handle_packet(hw,
2085                                         tid_agg_rx->reorder_buf[index],
2086                                         &status, rate);
2087                                 tid_agg_rx->stored_mpdu_num--;
2088                                 tid_agg_rx->reorder_buf[index] = NULL;
2089                         }
2090                         tid_agg_rx->head_seq_num =
2091                                 seq_inc(tid_agg_rx->head_seq_num);
2092                 }
2093                 if (bar_req)
2094                         return 1;
2095         }
2096
2097         /* now the new frame is always in the range of the reordering */
2098         /* buffer window */
2099         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2100                                 % tid_agg_rx->buf_size;
2101         /* check if we already stored this frame */
2102         if (tid_agg_rx->reorder_buf[index]) {
2103                 dev_kfree_skb(skb);
2104                 return 1;
2105         }
2106
2107         /* if arrived mpdu is in the right order and nothing else stored */
2108         /* release it immediately */
2109         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2110                         tid_agg_rx->stored_mpdu_num == 0) {
2111                 tid_agg_rx->head_seq_num =
2112                         seq_inc(tid_agg_rx->head_seq_num);
2113                 return 0;
2114         }
2115
2116         /* put the frame in the reordering buffer */
2117         tid_agg_rx->reorder_buf[index] = skb;
2118         tid_agg_rx->stored_mpdu_num++;
2119         /* release the buffer until next missing frame */
2120         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2121                                                 % tid_agg_rx->buf_size;
2122         while (tid_agg_rx->reorder_buf[index]) {
2123                 /* release the reordered frame back to stack */
2124                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2125                         sizeof(status));
2126                 sband = local->hw.wiphy->bands[status.band];
2127                 if (status.flag & RX_FLAG_HT)
2128                         rate = sband->bitrates; /* TODO: HT rates */
2129                 else
2130                         rate = &sband->bitrates[status.rate_idx];
2131                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2132                                              &status, rate);
2133                 tid_agg_rx->stored_mpdu_num--;
2134                 tid_agg_rx->reorder_buf[index] = NULL;
2135                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2136                 index = seq_sub(tid_agg_rx->head_seq_num,
2137                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2138         }
2139         return 1;
2140 }
2141
2142 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2143                                      struct sk_buff *skb)
2144 {
2145         struct ieee80211_hw *hw = &local->hw;
2146         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2147         struct sta_info *sta;
2148         struct tid_ampdu_rx *tid_agg_rx;
2149         u16 sc;
2150         u16 mpdu_seq_num;
2151         u8 ret = 0;
2152         int tid;
2153
2154         sta = sta_info_get(local, hdr->addr2);
2155         if (!sta)
2156                 return ret;
2157
2158         /* filter the QoS data rx stream according to
2159          * STA/TID and check if this STA/TID is on aggregation */
2160         if (!ieee80211_is_data_qos(hdr->frame_control))
2161                 goto end_reorder;
2162
2163         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2164
2165         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2166                 goto end_reorder;
2167
2168         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2169
2170         /* qos null data frames are excluded */
2171         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2172                 goto end_reorder;
2173
2174         /* new un-ordered ampdu frame - process it */
2175
2176         /* reset session timer */
2177         if (tid_agg_rx->timeout) {
2178                 unsigned long expires =
2179                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2180                 mod_timer(&tid_agg_rx->session_timer, expires);
2181         }
2182
2183         /* if this mpdu is fragmented - terminate rx aggregation session */
2184         sc = le16_to_cpu(hdr->seq_ctrl);
2185         if (sc & IEEE80211_SCTL_FRAG) {
2186                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2187                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2188                 ret = 1;
2189                 goto end_reorder;
2190         }
2191
2192         /* according to mpdu sequence number deal with reordering buffer */
2193         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2194         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2195                                                 mpdu_seq_num, 0);
2196  end_reorder:
2197         return ret;
2198 }
2199
2200 /*
2201  * This is the receive path handler. It is called by a low level driver when an
2202  * 802.11 MPDU is received from the hardware.
2203  */
2204 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2205                     struct ieee80211_rx_status *status)
2206 {
2207         struct ieee80211_local *local = hw_to_local(hw);
2208         struct ieee80211_rate *rate = NULL;
2209         struct ieee80211_supported_band *sband;
2210
2211         if (status->band < 0 ||
2212             status->band >= IEEE80211_NUM_BANDS) {
2213                 WARN_ON(1);
2214                 return;
2215         }
2216
2217         sband = local->hw.wiphy->bands[status->band];
2218         if (!sband) {
2219                 WARN_ON(1);
2220                 return;
2221         }
2222
2223         if (status->flag & RX_FLAG_HT) {
2224                 /* rate_idx is MCS index */
2225                 if (WARN_ON(status->rate_idx < 0 ||
2226                             status->rate_idx >= 76))
2227                         return;
2228                 /* HT rates are not in the table - use the highest legacy rate
2229                  * for now since other parts of mac80211 may not yet be fully
2230                  * MCS aware. */
2231                 rate = &sband->bitrates[sband->n_bitrates - 1];
2232         } else {
2233                 if (WARN_ON(status->rate_idx < 0 ||
2234                             status->rate_idx >= sband->n_bitrates))
2235                         return;
2236                 rate = &sband->bitrates[status->rate_idx];
2237         }
2238
2239         /*
2240          * key references and virtual interfaces are protected using RCU
2241          * and this requires that we are in a read-side RCU section during
2242          * receive processing
2243          */
2244         rcu_read_lock();
2245
2246         /*
2247          * Frames with failed FCS/PLCP checksum are not returned,
2248          * all other frames are returned without radiotap header
2249          * if it was previously present.
2250          * Also, frames with less than 16 bytes are dropped.
2251          */
2252         skb = ieee80211_rx_monitor(local, skb, status, rate);
2253         if (!skb) {
2254                 rcu_read_unlock();
2255                 return;
2256         }
2257
2258         if (!ieee80211_rx_reorder_ampdu(local, skb))
2259                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2260
2261         rcu_read_unlock();
2262 }
2263 EXPORT_SYMBOL(__ieee80211_rx);
2264
2265 /* This is a version of the rx handler that can be called from hard irq
2266  * context. Post the skb on the queue and schedule the tasklet */
2267 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2268                           struct ieee80211_rx_status *status)
2269 {
2270         struct ieee80211_local *local = hw_to_local(hw);
2271
2272         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2273
2274         skb->dev = local->mdev;
2275         /* copy status into skb->cb for use by tasklet */
2276         memcpy(skb->cb, status, sizeof(*status));
2277         skb->pkt_type = IEEE80211_RX_MSG;
2278         skb_queue_tail(&local->skb_queue, skb);
2279         tasklet_schedule(&local->tasklet);
2280 }
2281 EXPORT_SYMBOL(ieee80211_rx_irqsafe);