mac80211: clean up RX key checks
[linux-2.6.git] / net / mac80211 / rx.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010  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/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <net/mac80211.h>
20 #include <net/ieee80211_radiotap.h>
21
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "led.h"
25 #include "mesh.h"
26 #include "wep.h"
27 #include "wpa.h"
28 #include "tkip.h"
29 #include "wme.h"
30
31 /*
32  * monitor mode reception
33  *
34  * This function cleans up the SKB, i.e. it removes all the stuff
35  * only useful for monitoring.
36  */
37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
38                                            struct sk_buff *skb)
39 {
40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
41                 if (likely(skb->len > FCS_LEN))
42                         __pskb_trim(skb, skb->len - FCS_LEN);
43                 else {
44                         /* driver bug */
45                         WARN_ON(1);
46                         dev_kfree_skb(skb);
47                         skb = NULL;
48                 }
49         }
50
51         return skb;
52 }
53
54 static inline int should_drop_frame(struct sk_buff *skb,
55                                     int present_fcs_len)
56 {
57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
59
60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
61                 return 1;
62         if (unlikely(skb->len < 16 + present_fcs_len))
63                 return 1;
64         if (ieee80211_is_ctl(hdr->frame_control) &&
65             !ieee80211_is_pspoll(hdr->frame_control) &&
66             !ieee80211_is_back_req(hdr->frame_control))
67                 return 1;
68         return 0;
69 }
70
71 static int
72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
73                           struct ieee80211_rx_status *status)
74 {
75         int len;
76
77         /* always present fields */
78         len = sizeof(struct ieee80211_radiotap_header) + 9;
79
80         if (status->flag & RX_FLAG_TSFT)
81                 len += 8;
82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
83                 len += 1;
84
85         if (len & 1) /* padding for RX_FLAGS if necessary */
86                 len++;
87
88         return len;
89 }
90
91 /*
92  * ieee80211_add_rx_radiotap_header - add radiotap header
93  *
94  * add a radiotap header containing all the fields which the hardware provided.
95  */
96 static void
97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
98                                  struct sk_buff *skb,
99                                  struct ieee80211_rate *rate,
100                                  int rtap_len)
101 {
102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
103         struct ieee80211_radiotap_header *rthdr;
104         unsigned char *pos;
105         u16 rx_flags = 0;
106
107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
108         memset(rthdr, 0, rtap_len);
109
110         /* radiotap header, set always present flags */
111         rthdr->it_present =
112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
116         rthdr->it_len = cpu_to_le16(rtap_len);
117
118         pos = (unsigned char *)(rthdr+1);
119
120         /* the order of the following fields is important */
121
122         /* IEEE80211_RADIOTAP_TSFT */
123         if (status->flag & RX_FLAG_TSFT) {
124                 put_unaligned_le64(status->mactime, pos);
125                 rthdr->it_present |=
126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
127                 pos += 8;
128         }
129
130         /* IEEE80211_RADIOTAP_FLAGS */
131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
135         if (status->flag & RX_FLAG_SHORTPRE)
136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
137         pos++;
138
139         /* IEEE80211_RADIOTAP_RATE */
140         if (status->flag & RX_FLAG_HT) {
141                 /*
142                  * TODO: add following information into radiotap header once
143                  * suitable fields are defined for it:
144                  * - MCS index (status->rate_idx)
145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
147                  */
148                 *pos = 0;
149         } else {
150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
151                 *pos = rate->bitrate / 5;
152         }
153         pos++;
154
155         /* IEEE80211_RADIOTAP_CHANNEL */
156         put_unaligned_le16(status->freq, pos);
157         pos += 2;
158         if (status->band == IEEE80211_BAND_5GHZ)
159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
160                                    pos);
161         else if (status->flag & RX_FLAG_HT)
162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
163                                    pos);
164         else if (rate->flags & IEEE80211_RATE_ERP_G)
165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
166                                    pos);
167         else
168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
169                                    pos);
170         pos += 2;
171
172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
174                 *pos = status->signal;
175                 rthdr->it_present |=
176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
177                 pos++;
178         }
179
180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
181
182         /* IEEE80211_RADIOTAP_ANTENNA */
183         *pos = status->antenna;
184         pos++;
185
186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
187
188         /* IEEE80211_RADIOTAP_RX_FLAGS */
189         /* ensure 2 byte alignment for the 2 byte field as required */
190         if ((pos - (u8 *)rthdr) & 1)
191                 pos++;
192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
194         put_unaligned_le16(rx_flags, pos);
195         pos += 2;
196 }
197
198 /*
199  * This function copies a received frame to all monitor interfaces and
200  * returns a cleaned-up SKB that no longer includes the FCS nor the
201  * radiotap header the driver might have added.
202  */
203 static struct sk_buff *
204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
205                      struct ieee80211_rate *rate)
206 {
207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
208         struct ieee80211_sub_if_data *sdata;
209         int needed_headroom = 0;
210         struct sk_buff *skb, *skb2;
211         struct net_device *prev_dev = NULL;
212         int present_fcs_len = 0;
213
214         /*
215          * First, we may need to make a copy of the skb because
216          *  (1) we need to modify it for radiotap (if not present), and
217          *  (2) the other RX handlers will modify the skb we got.
218          *
219          * We don't need to, of course, if we aren't going to return
220          * the SKB because it has a bad FCS/PLCP checksum.
221          */
222
223         /* room for the radiotap header based on driver features */
224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
225
226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
227                 present_fcs_len = FCS_LEN;
228
229         /* make sure hdr->frame_control is on the linear part */
230         if (!pskb_may_pull(origskb, 2)) {
231                 dev_kfree_skb(origskb);
232                 return NULL;
233         }
234
235         if (!local->monitors) {
236                 if (should_drop_frame(origskb, present_fcs_len)) {
237                         dev_kfree_skb(origskb);
238                         return NULL;
239                 }
240
241                 return remove_monitor_info(local, origskb);
242         }
243
244         if (should_drop_frame(origskb, present_fcs_len)) {
245                 /* only need to expand headroom if necessary */
246                 skb = origskb;
247                 origskb = NULL;
248
249                 /*
250                  * This shouldn't trigger often because most devices have an
251                  * RX header they pull before we get here, and that should
252                  * be big enough for our radiotap information. We should
253                  * probably export the length to drivers so that we can have
254                  * them allocate enough headroom to start with.
255                  */
256                 if (skb_headroom(skb) < needed_headroom &&
257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
258                         dev_kfree_skb(skb);
259                         return NULL;
260                 }
261         } else {
262                 /*
263                  * Need to make a copy and possibly remove radiotap header
264                  * and FCS from the original.
265                  */
266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
267
268                 origskb = remove_monitor_info(local, origskb);
269
270                 if (!skb)
271                         return origskb;
272         }
273
274         /* prepend radiotap information */
275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
276
277         skb_reset_mac_header(skb);
278         skb->ip_summed = CHECKSUM_UNNECESSARY;
279         skb->pkt_type = PACKET_OTHERHOST;
280         skb->protocol = htons(ETH_P_802_2);
281
282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
284                         continue;
285
286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
287                         continue;
288
289                 if (!ieee80211_sdata_running(sdata))
290                         continue;
291
292                 if (prev_dev) {
293                         skb2 = skb_clone(skb, GFP_ATOMIC);
294                         if (skb2) {
295                                 skb2->dev = prev_dev;
296                                 netif_receive_skb(skb2);
297                         }
298                 }
299
300                 prev_dev = sdata->dev;
301                 sdata->dev->stats.rx_packets++;
302                 sdata->dev->stats.rx_bytes += skb->len;
303         }
304
305         if (prev_dev) {
306                 skb->dev = prev_dev;
307                 netif_receive_skb(skb);
308         } else
309                 dev_kfree_skb(skb);
310
311         return origskb;
312 }
313
314
315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
316 {
317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
318         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
319         int tid;
320
321         /* does the frame have a qos control field? */
322         if (ieee80211_is_data_qos(hdr->frame_control)) {
323                 u8 *qc = ieee80211_get_qos_ctl(hdr);
324                 /* frame has qos control */
325                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
326                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
327                         status->rx_flags |= IEEE80211_RX_AMSDU;
328         } else {
329                 /*
330                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
331                  *
332                  *      Sequence numbers for management frames, QoS data
333                  *      frames with a broadcast/multicast address in the
334                  *      Address 1 field, and all non-QoS data frames sent
335                  *      by QoS STAs are assigned using an additional single
336                  *      modulo-4096 counter, [...]
337                  *
338                  * We also use that counter for non-QoS STAs.
339                  */
340                 tid = NUM_RX_DATA_QUEUES - 1;
341         }
342
343         rx->queue = tid;
344         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
345          * For now, set skb->priority to 0 for other cases. */
346         rx->skb->priority = (tid > 7) ? 0 : tid;
347 }
348
349 /**
350  * DOC: Packet alignment
351  *
352  * Drivers always need to pass packets that are aligned to two-byte boundaries
353  * to the stack.
354  *
355  * Additionally, should, if possible, align the payload data in a way that
356  * guarantees that the contained IP header is aligned to a four-byte
357  * boundary. In the case of regular frames, this simply means aligning the
358  * payload to a four-byte boundary (because either the IP header is directly
359  * contained, or IV/RFC1042 headers that have a length divisible by four are
360  * in front of it).  If the payload data is not properly aligned and the
361  * architecture doesn't support efficient unaligned operations, mac80211
362  * will align the data.
363  *
364  * With A-MSDU frames, however, the payload data address must yield two modulo
365  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
366  * push the IP header further back to a multiple of four again. Thankfully, the
367  * specs were sane enough this time around to require padding each A-MSDU
368  * subframe to a length that is a multiple of four.
369  *
370  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
371  * the payload is not supported, the driver is required to move the 802.11
372  * header to be directly in front of the payload in that case.
373  */
374 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
375 {
376 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
377         WARN_ONCE((unsigned long)rx->skb->data & 1,
378                   "unaligned packet at 0x%p\n", rx->skb->data);
379 #endif
380 }
381
382
383 /* rx handlers */
384
385 static ieee80211_rx_result debug_noinline
386 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
387 {
388         struct ieee80211_local *local = rx->local;
389         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
390         struct sk_buff *skb = rx->skb;
391
392         if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN)))
393                 return RX_CONTINUE;
394
395         if (test_bit(SCAN_HW_SCANNING, &local->scanning))
396                 return ieee80211_scan_rx(rx->sdata, skb);
397
398         if (test_bit(SCAN_SW_SCANNING, &local->scanning)) {
399                 /* drop all the other packets during a software scan anyway */
400                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
401                         dev_kfree_skb(skb);
402                 return RX_QUEUED;
403         }
404
405         /* scanning finished during invoking of handlers */
406         I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
407         return RX_DROP_UNUSABLE;
408 }
409
410
411 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
412 {
413         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
414
415         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
416                 return 0;
417
418         return ieee80211_is_robust_mgmt_frame(hdr);
419 }
420
421
422 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
423 {
424         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
425
426         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
427                 return 0;
428
429         return ieee80211_is_robust_mgmt_frame(hdr);
430 }
431
432
433 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
434 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
435 {
436         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
437         struct ieee80211_mmie *mmie;
438
439         if (skb->len < 24 + sizeof(*mmie) ||
440             !is_multicast_ether_addr(hdr->da))
441                 return -1;
442
443         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
444                 return -1; /* not a robust management frame */
445
446         mmie = (struct ieee80211_mmie *)
447                 (skb->data + skb->len - sizeof(*mmie));
448         if (mmie->element_id != WLAN_EID_MMIE ||
449             mmie->length != sizeof(*mmie) - 2)
450                 return -1;
451
452         return le16_to_cpu(mmie->key_id);
453 }
454
455
456 static ieee80211_rx_result
457 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
458 {
459         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
460         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
461         char *dev_addr = rx->sdata->vif.addr;
462
463         if (ieee80211_is_data(hdr->frame_control)) {
464                 if (is_multicast_ether_addr(hdr->addr1)) {
465                         if (ieee80211_has_tods(hdr->frame_control) ||
466                                 !ieee80211_has_fromds(hdr->frame_control))
467                                 return RX_DROP_MONITOR;
468                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
469                                 return RX_DROP_MONITOR;
470                 } else {
471                         if (!ieee80211_has_a4(hdr->frame_control))
472                                 return RX_DROP_MONITOR;
473                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
474                                 return RX_DROP_MONITOR;
475                 }
476         }
477
478         /* If there is not an established peer link and this is not a peer link
479          * establisment frame, beacon or probe, drop the frame.
480          */
481
482         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
483                 struct ieee80211_mgmt *mgmt;
484
485                 if (!ieee80211_is_mgmt(hdr->frame_control))
486                         return RX_DROP_MONITOR;
487
488                 if (ieee80211_is_action(hdr->frame_control)) {
489                         mgmt = (struct ieee80211_mgmt *)hdr;
490                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
491                                 return RX_DROP_MONITOR;
492                         return RX_CONTINUE;
493                 }
494
495                 if (ieee80211_is_probe_req(hdr->frame_control) ||
496                     ieee80211_is_probe_resp(hdr->frame_control) ||
497                     ieee80211_is_beacon(hdr->frame_control))
498                         return RX_CONTINUE;
499
500                 return RX_DROP_MONITOR;
501
502         }
503
504 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
505
506         if (ieee80211_is_data(hdr->frame_control) &&
507             is_multicast_ether_addr(hdr->addr1) &&
508             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
509                 return RX_DROP_MONITOR;
510 #undef msh_h_get
511
512         return RX_CONTINUE;
513 }
514
515 #define SEQ_MODULO 0x1000
516 #define SEQ_MASK   0xfff
517
518 static inline int seq_less(u16 sq1, u16 sq2)
519 {
520         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
521 }
522
523 static inline u16 seq_inc(u16 sq)
524 {
525         return (sq + 1) & SEQ_MASK;
526 }
527
528 static inline u16 seq_sub(u16 sq1, u16 sq2)
529 {
530         return (sq1 - sq2) & SEQ_MASK;
531 }
532
533
534 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
535                                             struct tid_ampdu_rx *tid_agg_rx,
536                                             int index,
537                                             struct sk_buff_head *frames)
538 {
539         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
540
541         lockdep_assert_held(&tid_agg_rx->reorder_lock);
542
543         if (!skb)
544                 goto no_frame;
545
546         /* release the frame from the reorder ring buffer */
547         tid_agg_rx->stored_mpdu_num--;
548         tid_agg_rx->reorder_buf[index] = NULL;
549         __skb_queue_tail(frames, skb);
550
551 no_frame:
552         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
553 }
554
555 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
556                                              struct tid_ampdu_rx *tid_agg_rx,
557                                              u16 head_seq_num,
558                                              struct sk_buff_head *frames)
559 {
560         int index;
561
562         lockdep_assert_held(&tid_agg_rx->reorder_lock);
563
564         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
565                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
566                                                         tid_agg_rx->buf_size;
567                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
568         }
569 }
570
571 /*
572  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
573  * the skb was added to the buffer longer than this time ago, the earlier
574  * frames that have not yet been received are assumed to be lost and the skb
575  * can be released for processing. This may also release other skb's from the
576  * reorder buffer if there are no additional gaps between the frames.
577  *
578  * Callers must hold tid_agg_rx->reorder_lock.
579  */
580 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
581
582 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
583                                           struct tid_ampdu_rx *tid_agg_rx,
584                                           struct sk_buff_head *frames)
585 {
586         int index, j;
587
588         lockdep_assert_held(&tid_agg_rx->reorder_lock);
589
590         /* release the buffer until next missing frame */
591         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
592                                                 tid_agg_rx->buf_size;
593         if (!tid_agg_rx->reorder_buf[index] &&
594             tid_agg_rx->stored_mpdu_num > 1) {
595                 /*
596                  * No buffers ready to be released, but check whether any
597                  * frames in the reorder buffer have timed out.
598                  */
599                 int skipped = 1;
600                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
601                      j = (j + 1) % tid_agg_rx->buf_size) {
602                         if (!tid_agg_rx->reorder_buf[j]) {
603                                 skipped++;
604                                 continue;
605                         }
606                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
607                                         HT_RX_REORDER_BUF_TIMEOUT))
608                                 goto set_release_timer;
609
610 #ifdef CONFIG_MAC80211_HT_DEBUG
611                         if (net_ratelimit())
612                                 wiphy_debug(hw->wiphy,
613                                             "release an RX reorder frame due to timeout on earlier frames\n");
614 #endif
615                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
616                                                         j, frames);
617
618                         /*
619                          * Increment the head seq# also for the skipped slots.
620                          */
621                         tid_agg_rx->head_seq_num =
622                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
623                         skipped = 0;
624                 }
625         } else while (tid_agg_rx->reorder_buf[index]) {
626                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
627                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
628                                                         tid_agg_rx->buf_size;
629         }
630
631         /*
632          * Disable the reorder release timer for now.
633          *
634          * The current implementation lacks a proper locking scheme
635          * which would protect vital statistic and debug counters
636          * from being updated by two different but concurrent BHs.
637          *
638          * More information about the topic is available from:
639          * - thread: http://marc.info/?t=128635927000001
640          *
641          * What was wrong:
642          * =>  http://marc.info/?l=linux-wireless&m=128636170811964
643          * "Basically the thing is that until your patch, the data
644          *  in the struct didn't actually need locking because it
645          *  was accessed by the RX path only which is not concurrent."
646          *
647          * List of what needs to be fixed:
648          * => http://marc.info/?l=linux-wireless&m=128656352920957
649          *
650
651         if (tid_agg_rx->stored_mpdu_num) {
652                 j = index = seq_sub(tid_agg_rx->head_seq_num,
653                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
654
655                 for (; j != (index - 1) % tid_agg_rx->buf_size;
656                      j = (j + 1) % tid_agg_rx->buf_size) {
657                         if (tid_agg_rx->reorder_buf[j])
658                                 break;
659                 }
660
661  set_release_timer:
662
663                 mod_timer(&tid_agg_rx->reorder_timer,
664                           tid_agg_rx->reorder_time[j] +
665                           HT_RX_REORDER_BUF_TIMEOUT);
666         } else {
667                 del_timer(&tid_agg_rx->reorder_timer);
668         }
669         */
670
671 set_release_timer:
672         return;
673 }
674
675 /*
676  * As this function belongs to the RX path it must be under
677  * rcu_read_lock protection. It returns false if the frame
678  * can be processed immediately, true if it was consumed.
679  */
680 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
681                                              struct tid_ampdu_rx *tid_agg_rx,
682                                              struct sk_buff *skb,
683                                              struct sk_buff_head *frames)
684 {
685         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
686         u16 sc = le16_to_cpu(hdr->seq_ctrl);
687         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
688         u16 head_seq_num, buf_size;
689         int index;
690         bool ret = true;
691
692         spin_lock(&tid_agg_rx->reorder_lock);
693
694         buf_size = tid_agg_rx->buf_size;
695         head_seq_num = tid_agg_rx->head_seq_num;
696
697         /* frame with out of date sequence number */
698         if (seq_less(mpdu_seq_num, head_seq_num)) {
699                 dev_kfree_skb(skb);
700                 goto out;
701         }
702
703         /*
704          * If frame the sequence number exceeds our buffering window
705          * size release some previous frames to make room for this one.
706          */
707         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
708                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
709                 /* release stored frames up to new head to stack */
710                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
711                                                  frames);
712         }
713
714         /* Now the new frame is always in the range of the reordering buffer */
715
716         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
717
718         /* check if we already stored this frame */
719         if (tid_agg_rx->reorder_buf[index]) {
720                 dev_kfree_skb(skb);
721                 goto out;
722         }
723
724         /*
725          * If the current MPDU is in the right order and nothing else
726          * is stored we can process it directly, no need to buffer it.
727          */
728         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
729             tid_agg_rx->stored_mpdu_num == 0) {
730                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
731                 ret = false;
732                 goto out;
733         }
734
735         /* put the frame in the reordering buffer */
736         tid_agg_rx->reorder_buf[index] = skb;
737         tid_agg_rx->reorder_time[index] = jiffies;
738         tid_agg_rx->stored_mpdu_num++;
739         ieee80211_sta_reorder_release(hw, tid_agg_rx, frames);
740
741  out:
742         spin_unlock(&tid_agg_rx->reorder_lock);
743         return ret;
744 }
745
746 /*
747  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
748  * true if the MPDU was buffered, false if it should be processed.
749  */
750 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
751                                        struct sk_buff_head *frames)
752 {
753         struct sk_buff *skb = rx->skb;
754         struct ieee80211_local *local = rx->local;
755         struct ieee80211_hw *hw = &local->hw;
756         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
757         struct sta_info *sta = rx->sta;
758         struct tid_ampdu_rx *tid_agg_rx;
759         u16 sc;
760         int tid;
761
762         if (!ieee80211_is_data_qos(hdr->frame_control))
763                 goto dont_reorder;
764
765         /*
766          * filter the QoS data rx stream according to
767          * STA/TID and check if this STA/TID is on aggregation
768          */
769
770         if (!sta)
771                 goto dont_reorder;
772
773         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
774
775         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
776         if (!tid_agg_rx)
777                 goto dont_reorder;
778
779         /* qos null data frames are excluded */
780         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
781                 goto dont_reorder;
782
783         /* new, potentially un-ordered, ampdu frame - process it */
784
785         /* reset session timer */
786         if (tid_agg_rx->timeout)
787                 mod_timer(&tid_agg_rx->session_timer,
788                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
789
790         /* if this mpdu is fragmented - terminate rx aggregation session */
791         sc = le16_to_cpu(hdr->seq_ctrl);
792         if (sc & IEEE80211_SCTL_FRAG) {
793                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
794                 skb_queue_tail(&rx->sdata->skb_queue, skb);
795                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
796                 return;
797         }
798
799         /*
800          * No locking needed -- we will only ever process one
801          * RX packet at a time, and thus own tid_agg_rx. All
802          * other code manipulating it needs to (and does) make
803          * sure that we cannot get to it any more before doing
804          * anything with it.
805          */
806         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
807                 return;
808
809  dont_reorder:
810         __skb_queue_tail(frames, skb);
811 }
812
813 static ieee80211_rx_result debug_noinline
814 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
815 {
816         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
817         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
818
819         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
820         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
821                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
822                              rx->sta->last_seq_ctrl[rx->queue] ==
823                              hdr->seq_ctrl)) {
824                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
825                                 rx->local->dot11FrameDuplicateCount++;
826                                 rx->sta->num_duplicates++;
827                         }
828                         return RX_DROP_MONITOR;
829                 } else
830                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
831         }
832
833         if (unlikely(rx->skb->len < 16)) {
834                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
835                 return RX_DROP_MONITOR;
836         }
837
838         /* Drop disallowed frame classes based on STA auth/assoc state;
839          * IEEE 802.11, Chap 5.5.
840          *
841          * mac80211 filters only based on association state, i.e. it drops
842          * Class 3 frames from not associated stations. hostapd sends
843          * deauth/disassoc frames when needed. In addition, hostapd is
844          * responsible for filtering on both auth and assoc states.
845          */
846
847         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
848                 return ieee80211_rx_mesh_check(rx);
849
850         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
851                       ieee80211_is_pspoll(hdr->frame_control)) &&
852                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
853                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
854                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
855                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
856                      !ieee80211_has_tods(hdr->frame_control) &&
857                      ieee80211_is_data(hdr->frame_control)) ||
858                     !(status->rx_flags & IEEE80211_RX_RA_MATCH)) {
859                         /* Drop IBSS frames and frames for other hosts
860                          * silently. */
861                         return RX_DROP_MONITOR;
862                 }
863
864                 return RX_DROP_MONITOR;
865         }
866
867         return RX_CONTINUE;
868 }
869
870
871 static ieee80211_rx_result debug_noinline
872 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
873 {
874         struct sk_buff *skb = rx->skb;
875         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
876         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
877         int keyidx;
878         int hdrlen;
879         ieee80211_rx_result result = RX_DROP_UNUSABLE;
880         struct ieee80211_key *sta_ptk = NULL;
881         int mmie_keyidx = -1;
882         __le16 fc;
883
884         /*
885          * Key selection 101
886          *
887          * There are four types of keys:
888          *  - GTK (group keys)
889          *  - IGTK (group keys for management frames)
890          *  - PTK (pairwise keys)
891          *  - STK (station-to-station pairwise keys)
892          *
893          * When selecting a key, we have to distinguish between multicast
894          * (including broadcast) and unicast frames, the latter can only
895          * use PTKs and STKs while the former always use GTKs and IGTKs.
896          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
897          * unicast frames can also use key indices like GTKs. Hence, if we
898          * don't have a PTK/STK we check the key index for a WEP key.
899          *
900          * Note that in a regular BSS, multicast frames are sent by the
901          * AP only, associated stations unicast the frame to the AP first
902          * which then multicasts it on their behalf.
903          *
904          * There is also a slight problem in IBSS mode: GTKs are negotiated
905          * with each station, that is something we don't currently handle.
906          * The spec seems to expect that one negotiates the same key with
907          * every station but there's no such requirement; VLANs could be
908          * possible.
909          */
910
911         /*
912          * No point in finding a key and decrypting if the frame is neither
913          * addressed to us nor a multicast frame.
914          */
915         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
916                 return RX_CONTINUE;
917
918         /* start without a key */
919         rx->key = NULL;
920
921         if (rx->sta)
922                 sta_ptk = rcu_dereference(rx->sta->ptk);
923
924         fc = hdr->frame_control;
925
926         if (!ieee80211_has_protected(fc))
927                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
928
929         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
930                 rx->key = sta_ptk;
931                 if ((status->flag & RX_FLAG_DECRYPTED) &&
932                     (status->flag & RX_FLAG_IV_STRIPPED))
933                         return RX_CONTINUE;
934                 /* Skip decryption if the frame is not protected. */
935                 if (!ieee80211_has_protected(fc))
936                         return RX_CONTINUE;
937         } else if (mmie_keyidx >= 0) {
938                 /* Broadcast/multicast robust management frame / BIP */
939                 if ((status->flag & RX_FLAG_DECRYPTED) &&
940                     (status->flag & RX_FLAG_IV_STRIPPED))
941                         return RX_CONTINUE;
942
943                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
944                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
945                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
946                 if (rx->sta)
947                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
948                 if (!rx->key)
949                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
950         } else if (!ieee80211_has_protected(fc)) {
951                 /*
952                  * The frame was not protected, so skip decryption. However, we
953                  * need to set rx->key if there is a key that could have been
954                  * used so that the frame may be dropped if encryption would
955                  * have been expected.
956                  */
957                 struct ieee80211_key *key = NULL;
958                 struct ieee80211_sub_if_data *sdata = rx->sdata;
959                 int i;
960
961                 if (ieee80211_is_mgmt(fc) &&
962                     is_multicast_ether_addr(hdr->addr1) &&
963                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
964                         rx->key = key;
965                 else {
966                         if (rx->sta) {
967                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
968                                         key = rcu_dereference(rx->sta->gtk[i]);
969                                         if (key)
970                                                 break;
971                                 }
972                         }
973                         if (!key) {
974                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
975                                         key = rcu_dereference(sdata->keys[i]);
976                                         if (key)
977                                                 break;
978                                 }
979                         }
980                         if (key)
981                                 rx->key = key;
982                 }
983                 return RX_CONTINUE;
984         } else {
985                 u8 keyid;
986                 /*
987                  * The device doesn't give us the IV so we won't be
988                  * able to look up the key. That's ok though, we
989                  * don't need to decrypt the frame, we just won't
990                  * be able to keep statistics accurate.
991                  * Except for key threshold notifications, should
992                  * we somehow allow the driver to tell us which key
993                  * the hardware used if this flag is set?
994                  */
995                 if ((status->flag & RX_FLAG_DECRYPTED) &&
996                     (status->flag & RX_FLAG_IV_STRIPPED))
997                         return RX_CONTINUE;
998
999                 hdrlen = ieee80211_hdrlen(fc);
1000
1001                 if (rx->skb->len < 8 + hdrlen)
1002                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1003
1004                 /*
1005                  * no need to call ieee80211_wep_get_keyidx,
1006                  * it verifies a bunch of things we've done already
1007                  */
1008                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1009                 keyidx = keyid >> 6;
1010
1011                 /* check per-station GTK first, if multicast packet */
1012                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1013                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1014
1015                 /* if not found, try default key */
1016                 if (!rx->key) {
1017                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1018
1019                         /*
1020                          * RSNA-protected unicast frames should always be
1021                          * sent with pairwise or station-to-station keys,
1022                          * but for WEP we allow using a key index as well.
1023                          */
1024                         if (rx->key &&
1025                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1026                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1027                             !is_multicast_ether_addr(hdr->addr1))
1028                                 rx->key = NULL;
1029                 }
1030         }
1031
1032         if (rx->key) {
1033                 rx->key->tx_rx_count++;
1034                 /* TODO: add threshold stuff again */
1035         } else {
1036                 return RX_DROP_MONITOR;
1037         }
1038
1039         if (skb_linearize(rx->skb))
1040                 return RX_DROP_UNUSABLE;
1041         /* the hdr variable is invalid now! */
1042
1043         switch (rx->key->conf.cipher) {
1044         case WLAN_CIPHER_SUITE_WEP40:
1045         case WLAN_CIPHER_SUITE_WEP104:
1046                 /* Check for weak IVs if possible */
1047                 if (rx->sta && ieee80211_is_data(fc) &&
1048                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
1049                      !(status->flag & RX_FLAG_DECRYPTED)) &&
1050                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1051                         rx->sta->wep_weak_iv_count++;
1052
1053                 result = ieee80211_crypto_wep_decrypt(rx);
1054                 break;
1055         case WLAN_CIPHER_SUITE_TKIP:
1056                 result = ieee80211_crypto_tkip_decrypt(rx);
1057                 break;
1058         case WLAN_CIPHER_SUITE_CCMP:
1059                 result = ieee80211_crypto_ccmp_decrypt(rx);
1060                 break;
1061         case WLAN_CIPHER_SUITE_AES_CMAC:
1062                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1063                 break;
1064         default:
1065                 /*
1066                  * We can reach here only with HW-only algorithms
1067                  * but why didn't it decrypt the frame?!
1068                  */
1069                 return RX_DROP_UNUSABLE;
1070         }
1071
1072         /* either the frame has been decrypted or will be dropped */
1073         status->flag |= RX_FLAG_DECRYPTED;
1074
1075         return result;
1076 }
1077
1078 static ieee80211_rx_result debug_noinline
1079 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1080 {
1081         struct ieee80211_local *local;
1082         struct ieee80211_hdr *hdr;
1083         struct sk_buff *skb;
1084
1085         local = rx->local;
1086         skb = rx->skb;
1087         hdr = (struct ieee80211_hdr *) skb->data;
1088
1089         if (!local->pspolling)
1090                 return RX_CONTINUE;
1091
1092         if (!ieee80211_has_fromds(hdr->frame_control))
1093                 /* this is not from AP */
1094                 return RX_CONTINUE;
1095
1096         if (!ieee80211_is_data(hdr->frame_control))
1097                 return RX_CONTINUE;
1098
1099         if (!ieee80211_has_moredata(hdr->frame_control)) {
1100                 /* AP has no more frames buffered for us */
1101                 local->pspolling = false;
1102                 return RX_CONTINUE;
1103         }
1104
1105         /* more data bit is set, let's request a new frame from the AP */
1106         ieee80211_send_pspoll(local, rx->sdata);
1107
1108         return RX_CONTINUE;
1109 }
1110
1111 static void ap_sta_ps_start(struct sta_info *sta)
1112 {
1113         struct ieee80211_sub_if_data *sdata = sta->sdata;
1114         struct ieee80211_local *local = sdata->local;
1115
1116         atomic_inc(&sdata->bss->num_sta_ps);
1117         set_sta_flags(sta, WLAN_STA_PS_STA);
1118         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1119 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1120         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1121                sdata->name, sta->sta.addr, sta->sta.aid);
1122 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1123 }
1124
1125 static void ap_sta_ps_end(struct sta_info *sta)
1126 {
1127         struct ieee80211_sub_if_data *sdata = sta->sdata;
1128
1129         atomic_dec(&sdata->bss->num_sta_ps);
1130
1131 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1132         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1133                sdata->name, sta->sta.addr, sta->sta.aid);
1134 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1135
1136         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1137 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1138                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1139                        sdata->name, sta->sta.addr, sta->sta.aid);
1140 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1141                 return;
1142         }
1143
1144         ieee80211_sta_ps_deliver_wakeup(sta);
1145 }
1146
1147 static ieee80211_rx_result debug_noinline
1148 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1149 {
1150         struct sta_info *sta = rx->sta;
1151         struct sk_buff *skb = rx->skb;
1152         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1153         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1154
1155         if (!sta)
1156                 return RX_CONTINUE;
1157
1158         /*
1159          * Update last_rx only for IBSS packets which are for the current
1160          * BSSID to avoid keeping the current IBSS network alive in cases
1161          * where other STAs start using different BSSID.
1162          */
1163         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1164                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1165                                                 NL80211_IFTYPE_ADHOC);
1166                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1167                         sta->last_rx = jiffies;
1168         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1169                 /*
1170                  * Mesh beacons will update last_rx when if they are found to
1171                  * match the current local configuration when processed.
1172                  */
1173                 sta->last_rx = jiffies;
1174         }
1175
1176         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1177                 return RX_CONTINUE;
1178
1179         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1180                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1181
1182         sta->rx_fragments++;
1183         sta->rx_bytes += rx->skb->len;
1184         sta->last_signal = status->signal;
1185         ewma_add(&sta->avg_signal, -status->signal);
1186
1187         /*
1188          * Change STA power saving mode only at the end of a frame
1189          * exchange sequence.
1190          */
1191         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1192             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1193              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1194                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1195                         /*
1196                          * Ignore doze->wake transitions that are
1197                          * indicated by non-data frames, the standard
1198                          * is unclear here, but for example going to
1199                          * PS mode and then scanning would cause a
1200                          * doze->wake transition for the probe request,
1201                          * and that is clearly undesirable.
1202                          */
1203                         if (ieee80211_is_data(hdr->frame_control) &&
1204                             !ieee80211_has_pm(hdr->frame_control))
1205                                 ap_sta_ps_end(sta);
1206                 } else {
1207                         if (ieee80211_has_pm(hdr->frame_control))
1208                                 ap_sta_ps_start(sta);
1209                 }
1210         }
1211
1212         /*
1213          * Drop (qos-)data::nullfunc frames silently, since they
1214          * are used only to control station power saving mode.
1215          */
1216         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1217             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1218                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1219
1220                 /*
1221                  * If we receive a 4-addr nullfunc frame from a STA
1222                  * that was not moved to a 4-addr STA vlan yet, drop
1223                  * the frame to the monitor interface, to make sure
1224                  * that hostapd sees it
1225                  */
1226                 if (ieee80211_has_a4(hdr->frame_control) &&
1227                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1228                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1229                       !rx->sdata->u.vlan.sta)))
1230                         return RX_DROP_MONITOR;
1231                 /*
1232                  * Update counter and free packet here to avoid
1233                  * counting this as a dropped packed.
1234                  */
1235                 sta->rx_packets++;
1236                 dev_kfree_skb(rx->skb);
1237                 return RX_QUEUED;
1238         }
1239
1240         return RX_CONTINUE;
1241 } /* ieee80211_rx_h_sta_process */
1242
1243 static inline struct ieee80211_fragment_entry *
1244 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1245                          unsigned int frag, unsigned int seq, int rx_queue,
1246                          struct sk_buff **skb)
1247 {
1248         struct ieee80211_fragment_entry *entry;
1249         int idx;
1250
1251         idx = sdata->fragment_next;
1252         entry = &sdata->fragments[sdata->fragment_next++];
1253         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1254                 sdata->fragment_next = 0;
1255
1256         if (!skb_queue_empty(&entry->skb_list)) {
1257 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1258                 struct ieee80211_hdr *hdr =
1259                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1260                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1261                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1262                        "addr1=%pM addr2=%pM\n",
1263                        sdata->name, idx,
1264                        jiffies - entry->first_frag_time, entry->seq,
1265                        entry->last_frag, hdr->addr1, hdr->addr2);
1266 #endif
1267                 __skb_queue_purge(&entry->skb_list);
1268         }
1269
1270         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1271         *skb = NULL;
1272         entry->first_frag_time = jiffies;
1273         entry->seq = seq;
1274         entry->rx_queue = rx_queue;
1275         entry->last_frag = frag;
1276         entry->ccmp = 0;
1277         entry->extra_len = 0;
1278
1279         return entry;
1280 }
1281
1282 static inline struct ieee80211_fragment_entry *
1283 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1284                           unsigned int frag, unsigned int seq,
1285                           int rx_queue, struct ieee80211_hdr *hdr)
1286 {
1287         struct ieee80211_fragment_entry *entry;
1288         int i, idx;
1289
1290         idx = sdata->fragment_next;
1291         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1292                 struct ieee80211_hdr *f_hdr;
1293
1294                 idx--;
1295                 if (idx < 0)
1296                         idx = IEEE80211_FRAGMENT_MAX - 1;
1297
1298                 entry = &sdata->fragments[idx];
1299                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1300                     entry->rx_queue != rx_queue ||
1301                     entry->last_frag + 1 != frag)
1302                         continue;
1303
1304                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1305
1306                 /*
1307                  * Check ftype and addresses are equal, else check next fragment
1308                  */
1309                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1310                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1311                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1312                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1313                         continue;
1314
1315                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1316                         __skb_queue_purge(&entry->skb_list);
1317                         continue;
1318                 }
1319                 return entry;
1320         }
1321
1322         return NULL;
1323 }
1324
1325 static ieee80211_rx_result debug_noinline
1326 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1327 {
1328         struct ieee80211_hdr *hdr;
1329         u16 sc;
1330         __le16 fc;
1331         unsigned int frag, seq;
1332         struct ieee80211_fragment_entry *entry;
1333         struct sk_buff *skb;
1334         struct ieee80211_rx_status *status;
1335
1336         hdr = (struct ieee80211_hdr *)rx->skb->data;
1337         fc = hdr->frame_control;
1338         sc = le16_to_cpu(hdr->seq_ctrl);
1339         frag = sc & IEEE80211_SCTL_FRAG;
1340
1341         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1342                    (rx->skb)->len < 24 ||
1343                    is_multicast_ether_addr(hdr->addr1))) {
1344                 /* not fragmented */
1345                 goto out;
1346         }
1347         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1348
1349         if (skb_linearize(rx->skb))
1350                 return RX_DROP_UNUSABLE;
1351
1352         /*
1353          *  skb_linearize() might change the skb->data and
1354          *  previously cached variables (in this case, hdr) need to
1355          *  be refreshed with the new data.
1356          */
1357         hdr = (struct ieee80211_hdr *)rx->skb->data;
1358         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1359
1360         if (frag == 0) {
1361                 /* This is the first fragment of a new frame. */
1362                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1363                                                  rx->queue, &(rx->skb));
1364                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1365                     ieee80211_has_protected(fc)) {
1366                         int queue = ieee80211_is_mgmt(fc) ?
1367                                 NUM_RX_DATA_QUEUES : rx->queue;
1368                         /* Store CCMP PN so that we can verify that the next
1369                          * fragment has a sequential PN value. */
1370                         entry->ccmp = 1;
1371                         memcpy(entry->last_pn,
1372                                rx->key->u.ccmp.rx_pn[queue],
1373                                CCMP_PN_LEN);
1374                 }
1375                 return RX_QUEUED;
1376         }
1377
1378         /* This is a fragment for a frame that should already be pending in
1379          * fragment cache. Add this fragment to the end of the pending entry.
1380          */
1381         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1382         if (!entry) {
1383                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1384                 return RX_DROP_MONITOR;
1385         }
1386
1387         /* Verify that MPDUs within one MSDU have sequential PN values.
1388          * (IEEE 802.11i, 8.3.3.4.5) */
1389         if (entry->ccmp) {
1390                 int i;
1391                 u8 pn[CCMP_PN_LEN], *rpn;
1392                 int queue;
1393                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1394                         return RX_DROP_UNUSABLE;
1395                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1396                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1397                         pn[i]++;
1398                         if (pn[i])
1399                                 break;
1400                 }
1401                 queue = ieee80211_is_mgmt(fc) ?
1402                         NUM_RX_DATA_QUEUES : rx->queue;
1403                 rpn = rx->key->u.ccmp.rx_pn[queue];
1404                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1405                         return RX_DROP_UNUSABLE;
1406                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1407         }
1408
1409         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1410         __skb_queue_tail(&entry->skb_list, rx->skb);
1411         entry->last_frag = frag;
1412         entry->extra_len += rx->skb->len;
1413         if (ieee80211_has_morefrags(fc)) {
1414                 rx->skb = NULL;
1415                 return RX_QUEUED;
1416         }
1417
1418         rx->skb = __skb_dequeue(&entry->skb_list);
1419         if (skb_tailroom(rx->skb) < entry->extra_len) {
1420                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1421                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1422                                               GFP_ATOMIC))) {
1423                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1424                         __skb_queue_purge(&entry->skb_list);
1425                         return RX_DROP_UNUSABLE;
1426                 }
1427         }
1428         while ((skb = __skb_dequeue(&entry->skb_list))) {
1429                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1430                 dev_kfree_skb(skb);
1431         }
1432
1433         /* Complete frame has been reassembled - process it now */
1434         status = IEEE80211_SKB_RXCB(rx->skb);
1435         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1436
1437  out:
1438         if (rx->sta)
1439                 rx->sta->rx_packets++;
1440         if (is_multicast_ether_addr(hdr->addr1))
1441                 rx->local->dot11MulticastReceivedFrameCount++;
1442         else
1443                 ieee80211_led_rx(rx->local);
1444         return RX_CONTINUE;
1445 }
1446
1447 static ieee80211_rx_result debug_noinline
1448 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1449 {
1450         struct ieee80211_sub_if_data *sdata = rx->sdata;
1451         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1452         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1453
1454         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1455                    !(status->rx_flags & IEEE80211_RX_RA_MATCH)))
1456                 return RX_CONTINUE;
1457
1458         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1459             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1460                 return RX_DROP_UNUSABLE;
1461
1462         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1463                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1464         else
1465                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1466
1467         /* Free PS Poll skb here instead of returning RX_DROP that would
1468          * count as an dropped frame. */
1469         dev_kfree_skb(rx->skb);
1470
1471         return RX_QUEUED;
1472 }
1473
1474 static ieee80211_rx_result debug_noinline
1475 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1476 {
1477         u8 *data = rx->skb->data;
1478         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1479
1480         if (!ieee80211_is_data_qos(hdr->frame_control))
1481                 return RX_CONTINUE;
1482
1483         /* remove the qos control field, update frame type and meta-data */
1484         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1485                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1486         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1487         /* change frame type to non QOS */
1488         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1489
1490         return RX_CONTINUE;
1491 }
1492
1493 static int
1494 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1495 {
1496         if (unlikely(!rx->sta ||
1497             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1498                 return -EACCES;
1499
1500         return 0;
1501 }
1502
1503 static int
1504 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1505 {
1506         struct sk_buff *skb = rx->skb;
1507         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1508
1509         /*
1510          * Pass through unencrypted frames if the hardware has
1511          * decrypted them already.
1512          */
1513         if (status->flag & RX_FLAG_DECRYPTED)
1514                 return 0;
1515
1516         /* Drop unencrypted frames if key is set. */
1517         if (unlikely(!ieee80211_has_protected(fc) &&
1518                      !ieee80211_is_nullfunc(fc) &&
1519                      ieee80211_is_data(fc) &&
1520                      (rx->key || rx->sdata->drop_unencrypted)))
1521                 return -EACCES;
1522
1523         return 0;
1524 }
1525
1526 static int
1527 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1528 {
1529         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1530         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1531         __le16 fc = hdr->frame_control;
1532
1533         /*
1534          * Pass through unencrypted frames if the hardware has
1535          * decrypted them already.
1536          */
1537         if (status->flag & RX_FLAG_DECRYPTED)
1538                 return 0;
1539
1540         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1541                 if (unlikely(!ieee80211_has_protected(fc) &&
1542                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1543                              rx->key))
1544                         return -EACCES;
1545                 /* BIP does not use Protected field, so need to check MMIE */
1546                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1547                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1548                         return -EACCES;
1549                 /*
1550                  * When using MFP, Action frames are not allowed prior to
1551                  * having configured keys.
1552                  */
1553                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1554                              ieee80211_is_robust_mgmt_frame(
1555                                      (struct ieee80211_hdr *) rx->skb->data)))
1556                         return -EACCES;
1557         }
1558
1559         return 0;
1560 }
1561
1562 static int
1563 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1564 {
1565         struct ieee80211_sub_if_data *sdata = rx->sdata;
1566         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1567
1568         if (ieee80211_has_a4(hdr->frame_control) &&
1569             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1570                 return -1;
1571
1572         if (is_multicast_ether_addr(hdr->addr1) &&
1573             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1574              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1575                 return -1;
1576
1577         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1578 }
1579
1580 /*
1581  * requires that rx->skb is a frame with ethernet header
1582  */
1583 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1584 {
1585         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1586                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1587         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1588
1589         /*
1590          * Allow EAPOL frames to us/the PAE group address regardless
1591          * of whether the frame was encrypted or not.
1592          */
1593         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1594             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1595              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1596                 return true;
1597
1598         if (ieee80211_802_1x_port_control(rx) ||
1599             ieee80211_drop_unencrypted(rx, fc))
1600                 return false;
1601
1602         return true;
1603 }
1604
1605 /*
1606  * requires that rx->skb is a frame with ethernet header
1607  */
1608 static void
1609 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1610 {
1611         struct ieee80211_sub_if_data *sdata = rx->sdata;
1612         struct net_device *dev = sdata->dev;
1613         struct sk_buff *skb, *xmit_skb;
1614         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1615         struct sta_info *dsta;
1616         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1617
1618         skb = rx->skb;
1619         xmit_skb = NULL;
1620
1621         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1622              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1623             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1624             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1625             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1626                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1627                         /*
1628                          * send multicast frames both to higher layers in
1629                          * local net stack and back to the wireless medium
1630                          */
1631                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1632                         if (!xmit_skb && net_ratelimit())
1633                                 printk(KERN_DEBUG "%s: failed to clone "
1634                                        "multicast frame\n", dev->name);
1635                 } else {
1636                         dsta = sta_info_get(sdata, skb->data);
1637                         if (dsta) {
1638                                 /*
1639                                  * The destination station is associated to
1640                                  * this AP (in this VLAN), so send the frame
1641                                  * directly to it and do not pass it to local
1642                                  * net stack.
1643                                  */
1644                                 xmit_skb = skb;
1645                                 skb = NULL;
1646                         }
1647                 }
1648         }
1649
1650         if (skb) {
1651                 int align __maybe_unused;
1652
1653 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1654                 /*
1655                  * 'align' will only take the values 0 or 2 here
1656                  * since all frames are required to be aligned
1657                  * to 2-byte boundaries when being passed to
1658                  * mac80211. That also explains the __skb_push()
1659                  * below.
1660                  */
1661                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1662                 if (align) {
1663                         if (WARN_ON(skb_headroom(skb) < 3)) {
1664                                 dev_kfree_skb(skb);
1665                                 skb = NULL;
1666                         } else {
1667                                 u8 *data = skb->data;
1668                                 size_t len = skb_headlen(skb);
1669                                 skb->data -= align;
1670                                 memmove(skb->data, data, len);
1671                                 skb_set_tail_pointer(skb, len);
1672                         }
1673                 }
1674 #endif
1675
1676                 if (skb) {
1677                         /* deliver to local stack */
1678                         skb->protocol = eth_type_trans(skb, dev);
1679                         memset(skb->cb, 0, sizeof(skb->cb));
1680                         netif_receive_skb(skb);
1681                 }
1682         }
1683
1684         if (xmit_skb) {
1685                 /* send to wireless media */
1686                 xmit_skb->protocol = htons(ETH_P_802_3);
1687                 skb_reset_network_header(xmit_skb);
1688                 skb_reset_mac_header(xmit_skb);
1689                 dev_queue_xmit(xmit_skb);
1690         }
1691 }
1692
1693 static ieee80211_rx_result debug_noinline
1694 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1695 {
1696         struct net_device *dev = rx->sdata->dev;
1697         struct sk_buff *skb = rx->skb;
1698         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1699         __le16 fc = hdr->frame_control;
1700         struct sk_buff_head frame_list;
1701         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1702
1703         if (unlikely(!ieee80211_is_data(fc)))
1704                 return RX_CONTINUE;
1705
1706         if (unlikely(!ieee80211_is_data_present(fc)))
1707                 return RX_DROP_MONITOR;
1708
1709         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1710                 return RX_CONTINUE;
1711
1712         if (ieee80211_has_a4(hdr->frame_control) &&
1713             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1714             !rx->sdata->u.vlan.sta)
1715                 return RX_DROP_UNUSABLE;
1716
1717         if (is_multicast_ether_addr(hdr->addr1) &&
1718             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1719               rx->sdata->u.vlan.sta) ||
1720              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1721               rx->sdata->u.mgd.use_4addr)))
1722                 return RX_DROP_UNUSABLE;
1723
1724         skb->dev = dev;
1725         __skb_queue_head_init(&frame_list);
1726
1727         if (skb_linearize(skb))
1728                 return RX_DROP_UNUSABLE;
1729
1730         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1731                                  rx->sdata->vif.type,
1732                                  rx->local->hw.extra_tx_headroom);
1733
1734         while (!skb_queue_empty(&frame_list)) {
1735                 rx->skb = __skb_dequeue(&frame_list);
1736
1737                 if (!ieee80211_frame_allowed(rx, fc)) {
1738                         dev_kfree_skb(rx->skb);
1739                         continue;
1740                 }
1741                 dev->stats.rx_packets++;
1742                 dev->stats.rx_bytes += rx->skb->len;
1743
1744                 ieee80211_deliver_skb(rx);
1745         }
1746
1747         return RX_QUEUED;
1748 }
1749
1750 #ifdef CONFIG_MAC80211_MESH
1751 static ieee80211_rx_result
1752 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1753 {
1754         struct ieee80211_hdr *hdr;
1755         struct ieee80211s_hdr *mesh_hdr;
1756         unsigned int hdrlen;
1757         struct sk_buff *skb = rx->skb, *fwd_skb;
1758         struct ieee80211_local *local = rx->local;
1759         struct ieee80211_sub_if_data *sdata = rx->sdata;
1760         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1761
1762         hdr = (struct ieee80211_hdr *) skb->data;
1763         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1764         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1765
1766         if (!ieee80211_is_data(hdr->frame_control))
1767                 return RX_CONTINUE;
1768
1769         if (!mesh_hdr->ttl)
1770                 /* illegal frame */
1771                 return RX_DROP_MONITOR;
1772
1773         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1774                 struct mesh_path *mppath;
1775                 char *proxied_addr;
1776                 char *mpp_addr;
1777
1778                 if (is_multicast_ether_addr(hdr->addr1)) {
1779                         mpp_addr = hdr->addr3;
1780                         proxied_addr = mesh_hdr->eaddr1;
1781                 } else {
1782                         mpp_addr = hdr->addr4;
1783                         proxied_addr = mesh_hdr->eaddr2;
1784                 }
1785
1786                 rcu_read_lock();
1787                 mppath = mpp_path_lookup(proxied_addr, sdata);
1788                 if (!mppath) {
1789                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1790                 } else {
1791                         spin_lock_bh(&mppath->state_lock);
1792                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1793                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1794                         spin_unlock_bh(&mppath->state_lock);
1795                 }
1796                 rcu_read_unlock();
1797         }
1798
1799         /* Frame has reached destination.  Don't forward */
1800         if (!is_multicast_ether_addr(hdr->addr1) &&
1801             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1802                 return RX_CONTINUE;
1803
1804         mesh_hdr->ttl--;
1805
1806         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1807                 if (!mesh_hdr->ttl)
1808                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1809                                                      dropped_frames_ttl);
1810                 else {
1811                         struct ieee80211_hdr *fwd_hdr;
1812                         struct ieee80211_tx_info *info;
1813
1814                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1815
1816                         if (!fwd_skb && net_ratelimit())
1817                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1818                                                    sdata->name);
1819
1820                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1821                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1822                         info = IEEE80211_SKB_CB(fwd_skb);
1823                         memset(info, 0, sizeof(*info));
1824                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1825                         info->control.vif = &rx->sdata->vif;
1826                         skb_set_queue_mapping(skb,
1827                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1828                         ieee80211_set_qos_hdr(local, skb);
1829                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1830                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1831                                                                 fwded_mcast);
1832                         else {
1833                                 int err;
1834                                 /*
1835                                  * Save TA to addr1 to send TA a path error if a
1836                                  * suitable next hop is not found
1837                                  */
1838                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1839                                                 ETH_ALEN);
1840                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1841                                 /* Failed to immediately resolve next hop:
1842                                  * fwded frame was dropped or will be added
1843                                  * later to the pending skb queue.  */
1844                                 if (err)
1845                                         return RX_DROP_MONITOR;
1846
1847                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1848                                                                 fwded_unicast);
1849                         }
1850                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1851                                                      fwded_frames);
1852                         ieee80211_add_pending_skb(local, fwd_skb);
1853                 }
1854         }
1855
1856         if (is_multicast_ether_addr(hdr->addr1) ||
1857             sdata->dev->flags & IFF_PROMISC)
1858                 return RX_CONTINUE;
1859         else
1860                 return RX_DROP_MONITOR;
1861 }
1862 #endif
1863
1864 static ieee80211_rx_result debug_noinline
1865 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1866 {
1867         struct ieee80211_sub_if_data *sdata = rx->sdata;
1868         struct ieee80211_local *local = rx->local;
1869         struct net_device *dev = sdata->dev;
1870         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1871         __le16 fc = hdr->frame_control;
1872         int err;
1873
1874         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1875                 return RX_CONTINUE;
1876
1877         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1878                 return RX_DROP_MONITOR;
1879
1880         /*
1881          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1882          * that a 4-addr station can be detected and moved into a separate VLAN
1883          */
1884         if (ieee80211_has_a4(hdr->frame_control) &&
1885             sdata->vif.type == NL80211_IFTYPE_AP)
1886                 return RX_DROP_MONITOR;
1887
1888         err = __ieee80211_data_to_8023(rx);
1889         if (unlikely(err))
1890                 return RX_DROP_UNUSABLE;
1891
1892         if (!ieee80211_frame_allowed(rx, fc))
1893                 return RX_DROP_MONITOR;
1894
1895         rx->skb->dev = dev;
1896
1897         dev->stats.rx_packets++;
1898         dev->stats.rx_bytes += rx->skb->len;
1899
1900         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
1901             !is_multicast_ether_addr(((struct ethhdr *)rx->skb->data)->h_dest)) {
1902                         mod_timer(&local->dynamic_ps_timer, jiffies +
1903                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1904         }
1905
1906         ieee80211_deliver_skb(rx);
1907
1908         return RX_QUEUED;
1909 }
1910
1911 static ieee80211_rx_result debug_noinline
1912 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1913 {
1914         struct ieee80211_local *local = rx->local;
1915         struct ieee80211_hw *hw = &local->hw;
1916         struct sk_buff *skb = rx->skb;
1917         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1918         struct tid_ampdu_rx *tid_agg_rx;
1919         u16 start_seq_num;
1920         u16 tid;
1921
1922         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1923                 return RX_CONTINUE;
1924
1925         if (ieee80211_is_back_req(bar->frame_control)) {
1926                 struct {
1927                         __le16 control, start_seq_num;
1928                 } __packed bar_data;
1929
1930                 if (!rx->sta)
1931                         return RX_DROP_MONITOR;
1932
1933                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1934                                   &bar_data, sizeof(bar_data)))
1935                         return RX_DROP_MONITOR;
1936
1937                 tid = le16_to_cpu(bar_data.control) >> 12;
1938
1939                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1940                 if (!tid_agg_rx)
1941                         return RX_DROP_MONITOR;
1942
1943                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1944
1945                 /* reset session timer */
1946                 if (tid_agg_rx->timeout)
1947                         mod_timer(&tid_agg_rx->session_timer,
1948                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1949
1950                 spin_lock(&tid_agg_rx->reorder_lock);
1951                 /* release stored frames up to start of BAR */
1952                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1953                                                  frames);
1954                 spin_unlock(&tid_agg_rx->reorder_lock);
1955
1956                 kfree_skb(skb);
1957                 return RX_QUEUED;
1958         }
1959
1960         /*
1961          * After this point, we only want management frames,
1962          * so we can drop all remaining control frames to
1963          * cooked monitor interfaces.
1964          */
1965         return RX_DROP_MONITOR;
1966 }
1967
1968 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1969                                            struct ieee80211_mgmt *mgmt,
1970                                            size_t len)
1971 {
1972         struct ieee80211_local *local = sdata->local;
1973         struct sk_buff *skb;
1974         struct ieee80211_mgmt *resp;
1975
1976         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1977                 /* Not to own unicast address */
1978                 return;
1979         }
1980
1981         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1982             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1983                 /* Not from the current AP or not associated yet. */
1984                 return;
1985         }
1986
1987         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1988                 /* Too short SA Query request frame */
1989                 return;
1990         }
1991
1992         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1993         if (skb == NULL)
1994                 return;
1995
1996         skb_reserve(skb, local->hw.extra_tx_headroom);
1997         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1998         memset(resp, 0, 24);
1999         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2000         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2001         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2002         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2003                                           IEEE80211_STYPE_ACTION);
2004         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2005         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2006         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2007         memcpy(resp->u.action.u.sa_query.trans_id,
2008                mgmt->u.action.u.sa_query.trans_id,
2009                WLAN_SA_QUERY_TR_ID_LEN);
2010
2011         ieee80211_tx_skb(sdata, skb);
2012 }
2013
2014 static ieee80211_rx_result debug_noinline
2015 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2016 {
2017         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2018         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2019
2020         /*
2021          * From here on, look only at management frames.
2022          * Data and control frames are already handled,
2023          * and unknown (reserved) frames are useless.
2024          */
2025         if (rx->skb->len < 24)
2026                 return RX_DROP_MONITOR;
2027
2028         if (!ieee80211_is_mgmt(mgmt->frame_control))
2029                 return RX_DROP_MONITOR;
2030
2031         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2032                 return RX_DROP_MONITOR;
2033
2034         if (ieee80211_drop_unencrypted_mgmt(rx))
2035                 return RX_DROP_UNUSABLE;
2036
2037         return RX_CONTINUE;
2038 }
2039
2040 static ieee80211_rx_result debug_noinline
2041 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2042 {
2043         struct ieee80211_local *local = rx->local;
2044         struct ieee80211_sub_if_data *sdata = rx->sdata;
2045         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2046         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2047         int len = rx->skb->len;
2048
2049         if (!ieee80211_is_action(mgmt->frame_control))
2050                 return RX_CONTINUE;
2051
2052         /* drop too small frames */
2053         if (len < IEEE80211_MIN_ACTION_SIZE)
2054                 return RX_DROP_UNUSABLE;
2055
2056         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2057                 return RX_DROP_UNUSABLE;
2058
2059         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2060                 return RX_DROP_UNUSABLE;
2061
2062         switch (mgmt->u.action.category) {
2063         case WLAN_CATEGORY_BACK:
2064                 /*
2065                  * The aggregation code is not prepared to handle
2066                  * anything but STA/AP due to the BSSID handling;
2067                  * IBSS could work in the code but isn't supported
2068                  * by drivers or the standard.
2069                  */
2070                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2071                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2072                     sdata->vif.type != NL80211_IFTYPE_AP)
2073                         break;
2074
2075                 /* verify action_code is present */
2076                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2077                         break;
2078
2079                 switch (mgmt->u.action.u.addba_req.action_code) {
2080                 case WLAN_ACTION_ADDBA_REQ:
2081                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2082                                    sizeof(mgmt->u.action.u.addba_req)))
2083                                 goto invalid;
2084                         break;
2085                 case WLAN_ACTION_ADDBA_RESP:
2086                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2087                                    sizeof(mgmt->u.action.u.addba_resp)))
2088                                 goto invalid;
2089                         break;
2090                 case WLAN_ACTION_DELBA:
2091                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2092                                    sizeof(mgmt->u.action.u.delba)))
2093                                 goto invalid;
2094                         break;
2095                 default:
2096                         goto invalid;
2097                 }
2098
2099                 goto queue;
2100         case WLAN_CATEGORY_SPECTRUM_MGMT:
2101                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2102                         break;
2103
2104                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2105                         break;
2106
2107                 /* verify action_code is present */
2108                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2109                         break;
2110
2111                 switch (mgmt->u.action.u.measurement.action_code) {
2112                 case WLAN_ACTION_SPCT_MSR_REQ:
2113                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2114                                    sizeof(mgmt->u.action.u.measurement)))
2115                                 break;
2116                         ieee80211_process_measurement_req(sdata, mgmt, len);
2117                         goto handled;
2118                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2119                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2120                                    sizeof(mgmt->u.action.u.chan_switch)))
2121                                 break;
2122
2123                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2124                                 break;
2125
2126                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2127                                 break;
2128
2129                         goto queue;
2130                 }
2131                 break;
2132         case WLAN_CATEGORY_SA_QUERY:
2133                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2134                            sizeof(mgmt->u.action.u.sa_query)))
2135                         break;
2136
2137                 switch (mgmt->u.action.u.sa_query.action) {
2138                 case WLAN_ACTION_SA_QUERY_REQUEST:
2139                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2140                                 break;
2141                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2142                         goto handled;
2143                 }
2144                 break;
2145         case WLAN_CATEGORY_MESH_PLINK:
2146         case WLAN_CATEGORY_MESH_PATH_SEL:
2147                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2148                         break;
2149                 goto queue;
2150         }
2151
2152         return RX_CONTINUE;
2153
2154  invalid:
2155         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2156         /* will return in the next handlers */
2157         return RX_CONTINUE;
2158
2159  handled:
2160         if (rx->sta)
2161                 rx->sta->rx_packets++;
2162         dev_kfree_skb(rx->skb);
2163         return RX_QUEUED;
2164
2165  queue:
2166         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2167         skb_queue_tail(&sdata->skb_queue, rx->skb);
2168         ieee80211_queue_work(&local->hw, &sdata->work);
2169         if (rx->sta)
2170                 rx->sta->rx_packets++;
2171         return RX_QUEUED;
2172 }
2173
2174 static ieee80211_rx_result debug_noinline
2175 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2176 {
2177         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2178
2179         /* skip known-bad action frames and return them in the next handler */
2180         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2181                 return RX_CONTINUE;
2182
2183         /*
2184          * Getting here means the kernel doesn't know how to handle
2185          * it, but maybe userspace does ... include returned frames
2186          * so userspace can register for those to know whether ones
2187          * it transmitted were processed or returned.
2188          */
2189
2190         if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2191                              rx->skb->data, rx->skb->len,
2192                              GFP_ATOMIC)) {
2193                 if (rx->sta)
2194                         rx->sta->rx_packets++;
2195                 dev_kfree_skb(rx->skb);
2196                 return RX_QUEUED;
2197         }
2198
2199
2200         return RX_CONTINUE;
2201 }
2202
2203 static ieee80211_rx_result debug_noinline
2204 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2205 {
2206         struct ieee80211_local *local = rx->local;
2207         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2208         struct sk_buff *nskb;
2209         struct ieee80211_sub_if_data *sdata = rx->sdata;
2210         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2211
2212         if (!ieee80211_is_action(mgmt->frame_control))
2213                 return RX_CONTINUE;
2214
2215         /*
2216          * For AP mode, hostapd is responsible for handling any action
2217          * frames that we didn't handle, including returning unknown
2218          * ones. For all other modes we will return them to the sender,
2219          * setting the 0x80 bit in the action category, as required by
2220          * 802.11-2007 7.3.1.11.
2221          * Newer versions of hostapd shall also use the management frame
2222          * registration mechanisms, but older ones still use cooked
2223          * monitor interfaces so push all frames there.
2224          */
2225         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2226             (sdata->vif.type == NL80211_IFTYPE_AP ||
2227              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2228                 return RX_DROP_MONITOR;
2229
2230         /* do not return rejected action frames */
2231         if (mgmt->u.action.category & 0x80)
2232                 return RX_DROP_UNUSABLE;
2233
2234         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2235                                GFP_ATOMIC);
2236         if (nskb) {
2237                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2238
2239                 nmgmt->u.action.category |= 0x80;
2240                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2241                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2242
2243                 memset(nskb->cb, 0, sizeof(nskb->cb));
2244
2245                 ieee80211_tx_skb(rx->sdata, nskb);
2246         }
2247         dev_kfree_skb(rx->skb);
2248         return RX_QUEUED;
2249 }
2250
2251 static ieee80211_rx_result debug_noinline
2252 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2253 {
2254         struct ieee80211_sub_if_data *sdata = rx->sdata;
2255         ieee80211_rx_result rxs;
2256         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2257         __le16 stype;
2258
2259         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2260         if (rxs != RX_CONTINUE)
2261                 return rxs;
2262
2263         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2264
2265         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2266             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2267             sdata->vif.type != NL80211_IFTYPE_STATION)
2268                 return RX_DROP_MONITOR;
2269
2270         switch (stype) {
2271         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2272         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2273                 /* process for all: mesh, mlme, ibss */
2274                 break;
2275         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2276         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2277                 if (is_multicast_ether_addr(mgmt->da) &&
2278                     !is_broadcast_ether_addr(mgmt->da))
2279                         return RX_DROP_MONITOR;
2280
2281                 /* process only for station */
2282                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2283                         return RX_DROP_MONITOR;
2284                 break;
2285         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2286         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2287                 /* process only for ibss */
2288                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2289                         return RX_DROP_MONITOR;
2290                 break;
2291         default:
2292                 return RX_DROP_MONITOR;
2293         }
2294
2295         /* queue up frame and kick off work to process it */
2296         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2297         skb_queue_tail(&sdata->skb_queue, rx->skb);
2298         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2299         if (rx->sta)
2300                 rx->sta->rx_packets++;
2301
2302         return RX_QUEUED;
2303 }
2304
2305 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2306                                             struct ieee80211_rx_data *rx)
2307 {
2308         int keyidx;
2309         unsigned int hdrlen;
2310
2311         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2312         if (rx->skb->len >= hdrlen + 4)
2313                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2314         else
2315                 keyidx = -1;
2316
2317         if (!rx->sta) {
2318                 /*
2319                  * Some hardware seem to generate incorrect Michael MIC
2320                  * reports; ignore them to avoid triggering countermeasures.
2321                  */
2322                 return;
2323         }
2324
2325         if (!ieee80211_has_protected(hdr->frame_control))
2326                 return;
2327
2328         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2329                 /*
2330                  * APs with pairwise keys should never receive Michael MIC
2331                  * errors for non-zero keyidx because these are reserved for
2332                  * group keys and only the AP is sending real multicast
2333                  * frames in the BSS.
2334                  */
2335                 return;
2336         }
2337
2338         if (!ieee80211_is_data(hdr->frame_control) &&
2339             !ieee80211_is_auth(hdr->frame_control))
2340                 return;
2341
2342         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2343                                         GFP_ATOMIC);
2344 }
2345
2346 /* TODO: use IEEE80211_RX_FRAGMENTED */
2347 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2348                                         struct ieee80211_rate *rate)
2349 {
2350         struct ieee80211_sub_if_data *sdata;
2351         struct ieee80211_local *local = rx->local;
2352         struct ieee80211_rtap_hdr {
2353                 struct ieee80211_radiotap_header hdr;
2354                 u8 flags;
2355                 u8 rate_or_pad;
2356                 __le16 chan_freq;
2357                 __le16 chan_flags;
2358         } __packed *rthdr;
2359         struct sk_buff *skb = rx->skb, *skb2;
2360         struct net_device *prev_dev = NULL;
2361         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2362
2363         /*
2364          * If cooked monitor has been processed already, then
2365          * don't do it again. If not, set the flag.
2366          */
2367         if (rx->flags & IEEE80211_RX_CMNTR)
2368                 goto out_free_skb;
2369         rx->flags |= IEEE80211_RX_CMNTR;
2370
2371         if (skb_headroom(skb) < sizeof(*rthdr) &&
2372             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2373                 goto out_free_skb;
2374
2375         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2376         memset(rthdr, 0, sizeof(*rthdr));
2377         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2378         rthdr->hdr.it_present =
2379                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2380                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2381
2382         if (rate) {
2383                 rthdr->rate_or_pad = rate->bitrate / 5;
2384                 rthdr->hdr.it_present |=
2385                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2386         }
2387         rthdr->chan_freq = cpu_to_le16(status->freq);
2388
2389         if (status->band == IEEE80211_BAND_5GHZ)
2390                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2391                                                 IEEE80211_CHAN_5GHZ);
2392         else
2393                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2394                                                 IEEE80211_CHAN_2GHZ);
2395
2396         skb_set_mac_header(skb, 0);
2397         skb->ip_summed = CHECKSUM_UNNECESSARY;
2398         skb->pkt_type = PACKET_OTHERHOST;
2399         skb->protocol = htons(ETH_P_802_2);
2400
2401         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2402                 if (!ieee80211_sdata_running(sdata))
2403                         continue;
2404
2405                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2406                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2407                         continue;
2408
2409                 if (prev_dev) {
2410                         skb2 = skb_clone(skb, GFP_ATOMIC);
2411                         if (skb2) {
2412                                 skb2->dev = prev_dev;
2413                                 netif_receive_skb(skb2);
2414                         }
2415                 }
2416
2417                 prev_dev = sdata->dev;
2418                 sdata->dev->stats.rx_packets++;
2419                 sdata->dev->stats.rx_bytes += skb->len;
2420         }
2421
2422         if (prev_dev) {
2423                 skb->dev = prev_dev;
2424                 netif_receive_skb(skb);
2425                 return;
2426         }
2427
2428  out_free_skb:
2429         dev_kfree_skb(skb);
2430 }
2431
2432 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2433                                          ieee80211_rx_result res)
2434 {
2435         switch (res) {
2436         case RX_DROP_MONITOR:
2437                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2438                 if (rx->sta)
2439                         rx->sta->rx_dropped++;
2440                 /* fall through */
2441         case RX_CONTINUE: {
2442                 struct ieee80211_rate *rate = NULL;
2443                 struct ieee80211_supported_band *sband;
2444                 struct ieee80211_rx_status *status;
2445
2446                 status = IEEE80211_SKB_RXCB((rx->skb));
2447
2448                 sband = rx->local->hw.wiphy->bands[status->band];
2449                 if (!(status->flag & RX_FLAG_HT))
2450                         rate = &sband->bitrates[status->rate_idx];
2451
2452                 ieee80211_rx_cooked_monitor(rx, rate);
2453                 break;
2454                 }
2455         case RX_DROP_UNUSABLE:
2456                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2457                 if (rx->sta)
2458                         rx->sta->rx_dropped++;
2459                 dev_kfree_skb(rx->skb);
2460                 break;
2461         case RX_QUEUED:
2462                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2463                 break;
2464         }
2465 }
2466
2467 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2468                                   struct sk_buff_head *frames)
2469 {
2470         ieee80211_rx_result res = RX_DROP_MONITOR;
2471         struct sk_buff *skb;
2472
2473 #define CALL_RXH(rxh)                   \
2474         do {                            \
2475                 res = rxh(rx);          \
2476                 if (res != RX_CONTINUE) \
2477                         goto rxh_next;  \
2478         } while (0);
2479
2480         while ((skb = __skb_dequeue(frames))) {
2481                 /*
2482                  * all the other fields are valid across frames
2483                  * that belong to an aMPDU since they are on the
2484                  * same TID from the same station
2485                  */
2486                 rx->skb = skb;
2487                 rx->flags = 0;
2488
2489                 CALL_RXH(ieee80211_rx_h_decrypt)
2490                 CALL_RXH(ieee80211_rx_h_check_more_data)
2491                 CALL_RXH(ieee80211_rx_h_sta_process)
2492                 CALL_RXH(ieee80211_rx_h_defragment)
2493                 CALL_RXH(ieee80211_rx_h_ps_poll)
2494                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2495                 /* must be after MMIC verify so header is counted in MPDU mic */
2496                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2497                 CALL_RXH(ieee80211_rx_h_amsdu)
2498 #ifdef CONFIG_MAC80211_MESH
2499                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2500                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2501 #endif
2502                 CALL_RXH(ieee80211_rx_h_data)
2503
2504                 /* special treatment -- needs the queue */
2505                 res = ieee80211_rx_h_ctrl(rx, frames);
2506                 if (res != RX_CONTINUE)
2507                         goto rxh_next;
2508
2509                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2510                 CALL_RXH(ieee80211_rx_h_action)
2511                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2512                 CALL_RXH(ieee80211_rx_h_action_return)
2513                 CALL_RXH(ieee80211_rx_h_mgmt)
2514
2515  rxh_next:
2516                 ieee80211_rx_handlers_result(rx, res);
2517
2518 #undef CALL_RXH
2519         }
2520 }
2521
2522 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2523 {
2524         struct sk_buff_head reorder_release;
2525         ieee80211_rx_result res = RX_DROP_MONITOR;
2526
2527         __skb_queue_head_init(&reorder_release);
2528
2529 #define CALL_RXH(rxh)                   \
2530         do {                            \
2531                 res = rxh(rx);          \
2532                 if (res != RX_CONTINUE) \
2533                         goto rxh_next;  \
2534         } while (0);
2535
2536         CALL_RXH(ieee80211_rx_h_passive_scan)
2537         CALL_RXH(ieee80211_rx_h_check)
2538
2539         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2540
2541         ieee80211_rx_handlers(rx, &reorder_release);
2542         return;
2543
2544  rxh_next:
2545         ieee80211_rx_handlers_result(rx, res);
2546
2547 #undef CALL_RXH
2548 }
2549
2550 /*
2551  * This function makes calls into the RX path, therefore
2552  * it has to be invoked under RCU read lock.
2553  */
2554 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2555 {
2556         struct sk_buff_head frames;
2557         struct ieee80211_rx_data rx = {
2558                 .sta = sta,
2559                 .sdata = sta->sdata,
2560                 .local = sta->local,
2561                 .queue = tid,
2562         };
2563         struct tid_ampdu_rx *tid_agg_rx;
2564
2565         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2566         if (!tid_agg_rx)
2567                 return;
2568
2569         __skb_queue_head_init(&frames);
2570
2571         spin_lock(&tid_agg_rx->reorder_lock);
2572         ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx, &frames);
2573         spin_unlock(&tid_agg_rx->reorder_lock);
2574
2575         ieee80211_rx_handlers(&rx, &frames);
2576 }
2577
2578 /* main receive path */
2579
2580 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2581                                 struct ieee80211_hdr *hdr)
2582 {
2583         struct ieee80211_sub_if_data *sdata = rx->sdata;
2584         struct sk_buff *skb = rx->skb;
2585         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2586         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2587         int multicast = is_multicast_ether_addr(hdr->addr1);
2588
2589         switch (sdata->vif.type) {
2590         case NL80211_IFTYPE_STATION:
2591                 if (!bssid && !sdata->u.mgd.use_4addr)
2592                         return 0;
2593                 if (!multicast &&
2594                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2595                         if (!(sdata->dev->flags & IFF_PROMISC))
2596                                 return 0;
2597                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2598                 }
2599                 break;
2600         case NL80211_IFTYPE_ADHOC:
2601                 if (!bssid)
2602                         return 0;
2603                 if (ieee80211_is_beacon(hdr->frame_control)) {
2604                         return 1;
2605                 }
2606                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2607                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2608                                 return 0;
2609                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2610                 } else if (!multicast &&
2611                            compare_ether_addr(sdata->vif.addr,
2612                                               hdr->addr1) != 0) {
2613                         if (!(sdata->dev->flags & IFF_PROMISC))
2614                                 return 0;
2615                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2616                 } else if (!rx->sta) {
2617                         int rate_idx;
2618                         if (status->flag & RX_FLAG_HT)
2619                                 rate_idx = 0; /* TODO: HT rates */
2620                         else
2621                                 rate_idx = status->rate_idx;
2622                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2623                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2624                 }
2625                 break;
2626         case NL80211_IFTYPE_MESH_POINT:
2627                 if (!multicast &&
2628                     compare_ether_addr(sdata->vif.addr,
2629                                        hdr->addr1) != 0) {
2630                         if (!(sdata->dev->flags & IFF_PROMISC))
2631                                 return 0;
2632
2633                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2634                 }
2635                 break;
2636         case NL80211_IFTYPE_AP_VLAN:
2637         case NL80211_IFTYPE_AP:
2638                 if (!bssid) {
2639                         if (compare_ether_addr(sdata->vif.addr,
2640                                                hdr->addr1))
2641                                 return 0;
2642                 } else if (!ieee80211_bssid_match(bssid,
2643                                         sdata->vif.addr)) {
2644                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2645                                 return 0;
2646                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2647                 }
2648                 break;
2649         case NL80211_IFTYPE_WDS:
2650                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2651                         return 0;
2652                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2653                         return 0;
2654                 break;
2655         default:
2656                 /* should never get here */
2657                 WARN_ON(1);
2658                 break;
2659         }
2660
2661         return 1;
2662 }
2663
2664 /*
2665  * This function returns whether or not the SKB
2666  * was destined for RX processing or not, which,
2667  * if consume is true, is equivalent to whether
2668  * or not the skb was consumed.
2669  */
2670 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2671                                             struct sk_buff *skb, bool consume)
2672 {
2673         struct ieee80211_local *local = rx->local;
2674         struct ieee80211_sub_if_data *sdata = rx->sdata;
2675         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2676         struct ieee80211_hdr *hdr = (void *)skb->data;
2677         int prepares;
2678
2679         rx->skb = skb;
2680         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2681         prepares = prepare_for_handlers(rx, hdr);
2682
2683         if (!prepares)
2684                 return false;
2685
2686         if (status->flag & RX_FLAG_MMIC_ERROR) {
2687                 if (status->rx_flags & IEEE80211_RX_RA_MATCH)
2688                         ieee80211_rx_michael_mic_report(hdr, rx);
2689                 return false;
2690         }
2691
2692         if (!consume) {
2693                 skb = skb_copy(skb, GFP_ATOMIC);
2694                 if (!skb) {
2695                         if (net_ratelimit())
2696                                 wiphy_debug(local->hw.wiphy,
2697                                         "failed to copy multicast frame for %s\n",
2698                                         sdata->name);
2699                         return true;
2700                 }
2701
2702                 rx->skb = skb;
2703         }
2704
2705         ieee80211_invoke_rx_handlers(rx);
2706         return true;
2707 }
2708
2709 /*
2710  * This is the actual Rx frames handler. as it blongs to Rx path it must
2711  * be called with rcu_read_lock protection.
2712  */
2713 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2714                                          struct sk_buff *skb)
2715 {
2716         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2717         struct ieee80211_local *local = hw_to_local(hw);
2718         struct ieee80211_sub_if_data *sdata;
2719         struct ieee80211_hdr *hdr;
2720         __le16 fc;
2721         struct ieee80211_rx_data rx;
2722         struct ieee80211_sub_if_data *prev;
2723         struct sta_info *sta, *tmp, *prev_sta;
2724         int err = 0;
2725
2726         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2727         memset(&rx, 0, sizeof(rx));
2728         rx.skb = skb;
2729         rx.local = local;
2730
2731         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2732                 local->dot11ReceivedFragmentCount++;
2733
2734         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2735                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2736                 status->rx_flags |= IEEE80211_RX_IN_SCAN;
2737
2738         if (ieee80211_is_mgmt(fc))
2739                 err = skb_linearize(skb);
2740         else
2741                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2742
2743         if (err) {
2744                 dev_kfree_skb(skb);
2745                 return;
2746         }
2747
2748         hdr = (struct ieee80211_hdr *)skb->data;
2749         ieee80211_parse_qos(&rx);
2750         ieee80211_verify_alignment(&rx);
2751
2752         if (ieee80211_is_data(fc)) {
2753                 prev_sta = NULL;
2754
2755                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2756                         if (!prev_sta) {
2757                                 prev_sta = sta;
2758                                 continue;
2759                         }
2760
2761                         rx.sta = prev_sta;
2762                         rx.sdata = prev_sta->sdata;
2763                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2764
2765                         prev_sta = sta;
2766                 }
2767
2768                 if (prev_sta) {
2769                         rx.sta = prev_sta;
2770                         rx.sdata = prev_sta->sdata;
2771
2772                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2773                                 return;
2774                         goto out;
2775                 }
2776         }
2777
2778         prev = NULL;
2779
2780         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2781                 if (!ieee80211_sdata_running(sdata))
2782                         continue;
2783
2784                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2785                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2786                         continue;
2787
2788                 /*
2789                  * frame is destined for this interface, but if it's
2790                  * not also for the previous one we handle that after
2791                  * the loop to avoid copying the SKB once too much
2792                  */
2793
2794                 if (!prev) {
2795                         prev = sdata;
2796                         continue;
2797                 }
2798
2799                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2800                 rx.sdata = prev;
2801                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2802
2803                 prev = sdata;
2804         }
2805
2806         if (prev) {
2807                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2808                 rx.sdata = prev;
2809
2810                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2811                         return;
2812         }
2813
2814  out:
2815         dev_kfree_skb(skb);
2816 }
2817
2818 /*
2819  * This is the receive path handler. It is called by a low level driver when an
2820  * 802.11 MPDU is received from the hardware.
2821  */
2822 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2823 {
2824         struct ieee80211_local *local = hw_to_local(hw);
2825         struct ieee80211_rate *rate = NULL;
2826         struct ieee80211_supported_band *sband;
2827         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2828
2829         WARN_ON_ONCE(softirq_count() == 0);
2830
2831         if (WARN_ON(status->band < 0 ||
2832                     status->band >= IEEE80211_NUM_BANDS))
2833                 goto drop;
2834
2835         sband = local->hw.wiphy->bands[status->band];
2836         if (WARN_ON(!sband))
2837                 goto drop;
2838
2839         /*
2840          * If we're suspending, it is possible although not too likely
2841          * that we'd be receiving frames after having already partially
2842          * quiesced the stack. We can't process such frames then since
2843          * that might, for example, cause stations to be added or other
2844          * driver callbacks be invoked.
2845          */
2846         if (unlikely(local->quiescing || local->suspended))
2847                 goto drop;
2848
2849         /*
2850          * The same happens when we're not even started,
2851          * but that's worth a warning.
2852          */
2853         if (WARN_ON(!local->started))
2854                 goto drop;
2855
2856         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2857                 /*
2858                  * Validate the rate, unless a PLCP error means that
2859                  * we probably can't have a valid rate here anyway.
2860                  */
2861
2862                 if (status->flag & RX_FLAG_HT) {
2863                         /*
2864                          * rate_idx is MCS index, which can be [0-76]
2865                          * as documented on:
2866                          *
2867                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2868                          *
2869                          * Anything else would be some sort of driver or
2870                          * hardware error. The driver should catch hardware
2871                          * errors.
2872                          */
2873                         if (WARN((status->rate_idx < 0 ||
2874                                  status->rate_idx > 76),
2875                                  "Rate marked as an HT rate but passed "
2876                                  "status->rate_idx is not "
2877                                  "an MCS index [0-76]: %d (0x%02x)\n",
2878                                  status->rate_idx,
2879                                  status->rate_idx))
2880                                 goto drop;
2881                 } else {
2882                         if (WARN_ON(status->rate_idx < 0 ||
2883                                     status->rate_idx >= sband->n_bitrates))
2884                                 goto drop;
2885                         rate = &sband->bitrates[status->rate_idx];
2886                 }
2887         }
2888
2889         status->rx_flags = 0;
2890
2891         /*
2892          * key references and virtual interfaces are protected using RCU
2893          * and this requires that we are in a read-side RCU section during
2894          * receive processing
2895          */
2896         rcu_read_lock();
2897
2898         /*
2899          * Frames with failed FCS/PLCP checksum are not returned,
2900          * all other frames are returned without radiotap header
2901          * if it was previously present.
2902          * Also, frames with less than 16 bytes are dropped.
2903          */
2904         skb = ieee80211_rx_monitor(local, skb, rate);
2905         if (!skb) {
2906                 rcu_read_unlock();
2907                 return;
2908         }
2909
2910         __ieee80211_rx_handle_packet(hw, skb);
2911
2912         rcu_read_unlock();
2913
2914         return;
2915  drop:
2916         kfree_skb(skb);
2917 }
2918 EXPORT_SYMBOL(ieee80211_rx);
2919
2920 /* This is a version of the rx handler that can be called from hard irq
2921  * context. Post the skb on the queue and schedule the tasklet */
2922 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2923 {
2924         struct ieee80211_local *local = hw_to_local(hw);
2925
2926         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2927
2928         skb->pkt_type = IEEE80211_RX_MSG;
2929         skb_queue_tail(&local->skb_queue, skb);
2930         tasklet_schedule(&local->tasklet);
2931 }
2932 EXPORT_SYMBOL(ieee80211_rx_irqsafe);