b716fa2370b30a3c362f58a7f130bfda2c9575de
[linux-3.10.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_rx(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_rx(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         int tid;
319
320         /* does the frame have a qos control field? */
321         if (ieee80211_is_data_qos(hdr->frame_control)) {
322                 u8 *qc = ieee80211_get_qos_ctl(hdr);
323                 /* frame has qos control */
324                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
325                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
326                         rx->flags |= IEEE80211_RX_AMSDU;
327                 else
328                         rx->flags &= ~IEEE80211_RX_AMSDU;
329         } else {
330                 /*
331                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
332                  *
333                  *      Sequence numbers for management frames, QoS data
334                  *      frames with a broadcast/multicast address in the
335                  *      Address 1 field, and all non-QoS data frames sent
336                  *      by QoS STAs are assigned using an additional single
337                  *      modulo-4096 counter, [...]
338                  *
339                  * We also use that counter for non-QoS STAs.
340                  */
341                 tid = NUM_RX_DATA_QUEUES - 1;
342         }
343
344         rx->queue = tid;
345         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
346          * For now, set skb->priority to 0 for other cases. */
347         rx->skb->priority = (tid > 7) ? 0 : tid;
348 }
349
350 /**
351  * DOC: Packet alignment
352  *
353  * Drivers always need to pass packets that are aligned to two-byte boundaries
354  * to the stack.
355  *
356  * Additionally, should, if possible, align the payload data in a way that
357  * guarantees that the contained IP header is aligned to a four-byte
358  * boundary. In the case of regular frames, this simply means aligning the
359  * payload to a four-byte boundary (because either the IP header is directly
360  * contained, or IV/RFC1042 headers that have a length divisible by four are
361  * in front of it).  If the payload data is not properly aligned and the
362  * architecture doesn't support efficient unaligned operations, mac80211
363  * will align the data.
364  *
365  * With A-MSDU frames, however, the payload data address must yield two modulo
366  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
367  * push the IP header further back to a multiple of four again. Thankfully, the
368  * specs were sane enough this time around to require padding each A-MSDU
369  * subframe to a length that is a multiple of four.
370  *
371  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
372  * the payload is not supported, the driver is required to move the 802.11
373  * header to be directly in front of the payload in that case.
374  */
375 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
376 {
377 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
378         WARN_ONCE((unsigned long)rx->skb->data & 1,
379                   "unaligned packet at 0x%p\n", rx->skb->data);
380 #endif
381 }
382
383
384 /* rx handlers */
385
386 static ieee80211_rx_result debug_noinline
387 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
388 {
389         struct ieee80211_local *local = rx->local;
390         struct sk_buff *skb = rx->skb;
391
392         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
393                 return ieee80211_scan_rx(rx->sdata, skb);
394
395         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
396                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
397                 /* drop all the other packets during a software scan anyway */
398                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
399                         dev_kfree_skb(skb);
400                 return RX_QUEUED;
401         }
402
403         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
404                 /* scanning finished during invoking of handlers */
405                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
406                 return RX_DROP_UNUSABLE;
407         }
408
409         return RX_CONTINUE;
410 }
411
412
413 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
414 {
415         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
416
417         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
418                 return 0;
419
420         return ieee80211_is_robust_mgmt_frame(hdr);
421 }
422
423
424 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
425 {
426         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
427
428         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
429                 return 0;
430
431         return ieee80211_is_robust_mgmt_frame(hdr);
432 }
433
434
435 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
436 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
437 {
438         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
439         struct ieee80211_mmie *mmie;
440
441         if (skb->len < 24 + sizeof(*mmie) ||
442             !is_multicast_ether_addr(hdr->da))
443                 return -1;
444
445         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
446                 return -1; /* not a robust management frame */
447
448         mmie = (struct ieee80211_mmie *)
449                 (skb->data + skb->len - sizeof(*mmie));
450         if (mmie->element_id != WLAN_EID_MMIE ||
451             mmie->length != sizeof(*mmie) - 2)
452                 return -1;
453
454         return le16_to_cpu(mmie->key_id);
455 }
456
457
458 static ieee80211_rx_result
459 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
460 {
461         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
462         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
463         char *dev_addr = rx->sdata->vif.addr;
464
465         if (ieee80211_is_data(hdr->frame_control)) {
466                 if (is_multicast_ether_addr(hdr->addr1)) {
467                         if (ieee80211_has_tods(hdr->frame_control) ||
468                                 !ieee80211_has_fromds(hdr->frame_control))
469                                 return RX_DROP_MONITOR;
470                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
471                                 return RX_DROP_MONITOR;
472                 } else {
473                         if (!ieee80211_has_a4(hdr->frame_control))
474                                 return RX_DROP_MONITOR;
475                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
476                                 return RX_DROP_MONITOR;
477                 }
478         }
479
480         /* If there is not an established peer link and this is not a peer link
481          * establisment frame, beacon or probe, drop the frame.
482          */
483
484         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
485                 struct ieee80211_mgmt *mgmt;
486
487                 if (!ieee80211_is_mgmt(hdr->frame_control))
488                         return RX_DROP_MONITOR;
489
490                 if (ieee80211_is_action(hdr->frame_control)) {
491                         mgmt = (struct ieee80211_mgmt *)hdr;
492                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
493                                 return RX_DROP_MONITOR;
494                         return RX_CONTINUE;
495                 }
496
497                 if (ieee80211_is_probe_req(hdr->frame_control) ||
498                     ieee80211_is_probe_resp(hdr->frame_control) ||
499                     ieee80211_is_beacon(hdr->frame_control))
500                         return RX_CONTINUE;
501
502                 return RX_DROP_MONITOR;
503
504         }
505
506 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
507
508         if (ieee80211_is_data(hdr->frame_control) &&
509             is_multicast_ether_addr(hdr->addr1) &&
510             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
511                 return RX_DROP_MONITOR;
512 #undef msh_h_get
513
514         return RX_CONTINUE;
515 }
516
517 #define SEQ_MODULO 0x1000
518 #define SEQ_MASK   0xfff
519
520 static inline int seq_less(u16 sq1, u16 sq2)
521 {
522         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
523 }
524
525 static inline u16 seq_inc(u16 sq)
526 {
527         return (sq + 1) & SEQ_MASK;
528 }
529
530 static inline u16 seq_sub(u16 sq1, u16 sq2)
531 {
532         return (sq1 - sq2) & SEQ_MASK;
533 }
534
535
536 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
537                                             struct tid_ampdu_rx *tid_agg_rx,
538                                             int index,
539                                             struct sk_buff_head *frames)
540 {
541         struct ieee80211_supported_band *sband;
542         struct ieee80211_rate *rate = NULL;
543         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
544         struct ieee80211_rx_status *status;
545
546         if (!skb)
547                 goto no_frame;
548
549         status = IEEE80211_SKB_RXCB(skb);
550
551         /* release the reordered frames to stack */
552         sband = hw->wiphy->bands[status->band];
553         if (!(status->flag & RX_FLAG_HT))
554                 rate = &sband->bitrates[status->rate_idx];
555         tid_agg_rx->stored_mpdu_num--;
556         tid_agg_rx->reorder_buf[index] = NULL;
557         __skb_queue_tail(frames, skb);
558
559 no_frame:
560         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
561 }
562
563 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
564                                              struct tid_ampdu_rx *tid_agg_rx,
565                                              u16 head_seq_num,
566                                              struct sk_buff_head *frames)
567 {
568         int index;
569
570         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
571                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
572                                                         tid_agg_rx->buf_size;
573                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
574         }
575 }
576
577 /*
578  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
579  * the skb was added to the buffer longer than this time ago, the earlier
580  * frames that have not yet been received are assumed to be lost and the skb
581  * can be released for processing. This may also release other skb's from the
582  * reorder buffer if there are no additional gaps between the frames.
583  */
584 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
585
586 /*
587  * As this function belongs to the RX path it must be under
588  * rcu_read_lock protection. It returns false if the frame
589  * can be processed immediately, true if it was consumed.
590  */
591 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
592                                              struct tid_ampdu_rx *tid_agg_rx,
593                                              struct sk_buff *skb,
594                                              struct sk_buff_head *frames)
595 {
596         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
597         u16 sc = le16_to_cpu(hdr->seq_ctrl);
598         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
599         u16 head_seq_num, buf_size;
600         int index;
601
602         buf_size = tid_agg_rx->buf_size;
603         head_seq_num = tid_agg_rx->head_seq_num;
604
605         /* frame with out of date sequence number */
606         if (seq_less(mpdu_seq_num, head_seq_num)) {
607                 dev_kfree_skb(skb);
608                 return true;
609         }
610
611         /*
612          * If frame the sequence number exceeds our buffering window
613          * size release some previous frames to make room for this one.
614          */
615         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
616                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
617                 /* release stored frames up to new head to stack */
618                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
619                                                  frames);
620         }
621
622         /* Now the new frame is always in the range of the reordering buffer */
623
624         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
625
626         /* check if we already stored this frame */
627         if (tid_agg_rx->reorder_buf[index]) {
628                 dev_kfree_skb(skb);
629                 return true;
630         }
631
632         /*
633          * If the current MPDU is in the right order and nothing else
634          * is stored we can process it directly, no need to buffer it.
635          */
636         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
637             tid_agg_rx->stored_mpdu_num == 0) {
638                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
639                 return false;
640         }
641
642         /* put the frame in the reordering buffer */
643         tid_agg_rx->reorder_buf[index] = skb;
644         tid_agg_rx->reorder_time[index] = jiffies;
645         tid_agg_rx->stored_mpdu_num++;
646         /* release the buffer until next missing frame */
647         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
648                                                 tid_agg_rx->buf_size;
649         if (!tid_agg_rx->reorder_buf[index] &&
650             tid_agg_rx->stored_mpdu_num > 1) {
651                 /*
652                  * No buffers ready to be released, but check whether any
653                  * frames in the reorder buffer have timed out.
654                  */
655                 int j;
656                 int skipped = 1;
657                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
658                      j = (j + 1) % tid_agg_rx->buf_size) {
659                         if (!tid_agg_rx->reorder_buf[j]) {
660                                 skipped++;
661                                 continue;
662                         }
663                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
664                                         HT_RX_REORDER_BUF_TIMEOUT))
665                                 break;
666
667 #ifdef CONFIG_MAC80211_HT_DEBUG
668                         if (net_ratelimit())
669                                 printk(KERN_DEBUG "%s: release an RX reorder "
670                                        "frame due to timeout on earlier "
671                                        "frames\n",
672                                        wiphy_name(hw->wiphy));
673 #endif
674                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
675                                                         j, frames);
676
677                         /*
678                          * Increment the head seq# also for the skipped slots.
679                          */
680                         tid_agg_rx->head_seq_num =
681                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
682                         skipped = 0;
683                 }
684         } else while (tid_agg_rx->reorder_buf[index]) {
685                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
686                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
687                                                         tid_agg_rx->buf_size;
688         }
689
690         return true;
691 }
692
693 /*
694  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
695  * true if the MPDU was buffered, false if it should be processed.
696  */
697 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
698                                        struct sk_buff_head *frames)
699 {
700         struct sk_buff *skb = rx->skb;
701         struct ieee80211_local *local = rx->local;
702         struct ieee80211_hw *hw = &local->hw;
703         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
704         struct sta_info *sta = rx->sta;
705         struct tid_ampdu_rx *tid_agg_rx;
706         u16 sc;
707         int tid;
708
709         if (!ieee80211_is_data_qos(hdr->frame_control))
710                 goto dont_reorder;
711
712         /*
713          * filter the QoS data rx stream according to
714          * STA/TID and check if this STA/TID is on aggregation
715          */
716
717         if (!sta)
718                 goto dont_reorder;
719
720         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
721
722         spin_lock(&sta->lock);
723
724         if (!sta->ampdu_mlme.tid_active_rx[tid])
725                 goto dont_reorder_unlock;
726
727         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
728
729         /* qos null data frames are excluded */
730         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
731                 goto dont_reorder_unlock;
732
733         /* new, potentially un-ordered, ampdu frame - process it */
734
735         /* reset session timer */
736         if (tid_agg_rx->timeout)
737                 mod_timer(&tid_agg_rx->session_timer,
738                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
739
740         /* if this mpdu is fragmented - terminate rx aggregation session */
741         sc = le16_to_cpu(hdr->seq_ctrl);
742         if (sc & IEEE80211_SCTL_FRAG) {
743                 spin_unlock(&sta->lock);
744                 skb_queue_tail(&rx->sdata->skb_queue, skb);
745                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
746                 return;
747         }
748
749         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames)) {
750                 spin_unlock(&sta->lock);
751                 return;
752         }
753
754  dont_reorder_unlock:
755         spin_unlock(&sta->lock);
756  dont_reorder:
757         __skb_queue_tail(frames, skb);
758 }
759
760 static ieee80211_rx_result debug_noinline
761 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
762 {
763         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
764
765         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
766         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
767                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
768                              rx->sta->last_seq_ctrl[rx->queue] ==
769                              hdr->seq_ctrl)) {
770                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
771                                 rx->local->dot11FrameDuplicateCount++;
772                                 rx->sta->num_duplicates++;
773                         }
774                         return RX_DROP_MONITOR;
775                 } else
776                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
777         }
778
779         if (unlikely(rx->skb->len < 16)) {
780                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
781                 return RX_DROP_MONITOR;
782         }
783
784         /* Drop disallowed frame classes based on STA auth/assoc state;
785          * IEEE 802.11, Chap 5.5.
786          *
787          * mac80211 filters only based on association state, i.e. it drops
788          * Class 3 frames from not associated stations. hostapd sends
789          * deauth/disassoc frames when needed. In addition, hostapd is
790          * responsible for filtering on both auth and assoc states.
791          */
792
793         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
794                 return ieee80211_rx_mesh_check(rx);
795
796         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
797                       ieee80211_is_pspoll(hdr->frame_control)) &&
798                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
799                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
800                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
801                      !ieee80211_has_tods(hdr->frame_control) &&
802                      ieee80211_is_data(hdr->frame_control)) ||
803                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
804                         /* Drop IBSS frames and frames for other hosts
805                          * silently. */
806                         return RX_DROP_MONITOR;
807                 }
808
809                 return RX_DROP_MONITOR;
810         }
811
812         return RX_CONTINUE;
813 }
814
815
816 static ieee80211_rx_result debug_noinline
817 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
818 {
819         struct sk_buff *skb = rx->skb;
820         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
821         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
822         int keyidx;
823         int hdrlen;
824         ieee80211_rx_result result = RX_DROP_UNUSABLE;
825         struct ieee80211_key *stakey = NULL;
826         int mmie_keyidx = -1;
827         __le16 fc;
828
829         /*
830          * Key selection 101
831          *
832          * There are four types of keys:
833          *  - GTK (group keys)
834          *  - IGTK (group keys for management frames)
835          *  - PTK (pairwise keys)
836          *  - STK (station-to-station pairwise keys)
837          *
838          * When selecting a key, we have to distinguish between multicast
839          * (including broadcast) and unicast frames, the latter can only
840          * use PTKs and STKs while the former always use GTKs and IGTKs.
841          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
842          * unicast frames can also use key indices like GTKs. Hence, if we
843          * don't have a PTK/STK we check the key index for a WEP key.
844          *
845          * Note that in a regular BSS, multicast frames are sent by the
846          * AP only, associated stations unicast the frame to the AP first
847          * which then multicasts it on their behalf.
848          *
849          * There is also a slight problem in IBSS mode: GTKs are negotiated
850          * with each station, that is something we don't currently handle.
851          * The spec seems to expect that one negotiates the same key with
852          * every station but there's no such requirement; VLANs could be
853          * possible.
854          */
855
856         /*
857          * No point in finding a key and decrypting if the frame is neither
858          * addressed to us nor a multicast frame.
859          */
860         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
861                 return RX_CONTINUE;
862
863         /* start without a key */
864         rx->key = NULL;
865
866         if (rx->sta)
867                 stakey = rcu_dereference(rx->sta->key);
868
869         fc = hdr->frame_control;
870
871         if (!ieee80211_has_protected(fc))
872                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
873
874         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
875                 rx->key = stakey;
876                 /* Skip decryption if the frame is not protected. */
877                 if (!ieee80211_has_protected(fc))
878                         return RX_CONTINUE;
879         } else if (mmie_keyidx >= 0) {
880                 /* Broadcast/multicast robust management frame / BIP */
881                 if ((status->flag & RX_FLAG_DECRYPTED) &&
882                     (status->flag & RX_FLAG_IV_STRIPPED))
883                         return RX_CONTINUE;
884
885                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
886                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
887                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
888                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
889         } else if (!ieee80211_has_protected(fc)) {
890                 /*
891                  * The frame was not protected, so skip decryption. However, we
892                  * need to set rx->key if there is a key that could have been
893                  * used so that the frame may be dropped if encryption would
894                  * have been expected.
895                  */
896                 struct ieee80211_key *key = NULL;
897                 if (ieee80211_is_mgmt(fc) &&
898                     is_multicast_ether_addr(hdr->addr1) &&
899                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
900                         rx->key = key;
901                 else if ((key = rcu_dereference(rx->sdata->default_key)))
902                         rx->key = key;
903                 return RX_CONTINUE;
904         } else {
905                 u8 keyid;
906                 /*
907                  * The device doesn't give us the IV so we won't be
908                  * able to look up the key. That's ok though, we
909                  * don't need to decrypt the frame, we just won't
910                  * be able to keep statistics accurate.
911                  * Except for key threshold notifications, should
912                  * we somehow allow the driver to tell us which key
913                  * the hardware used if this flag is set?
914                  */
915                 if ((status->flag & RX_FLAG_DECRYPTED) &&
916                     (status->flag & RX_FLAG_IV_STRIPPED))
917                         return RX_CONTINUE;
918
919                 hdrlen = ieee80211_hdrlen(fc);
920
921                 if (rx->skb->len < 8 + hdrlen)
922                         return RX_DROP_UNUSABLE; /* TODO: count this? */
923
924                 /*
925                  * no need to call ieee80211_wep_get_keyidx,
926                  * it verifies a bunch of things we've done already
927                  */
928                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
929                 keyidx = keyid >> 6;
930
931                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
932
933                 /*
934                  * RSNA-protected unicast frames should always be sent with
935                  * pairwise or station-to-station keys, but for WEP we allow
936                  * using a key index as well.
937                  */
938                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
939                     !is_multicast_ether_addr(hdr->addr1))
940                         rx->key = NULL;
941         }
942
943         if (rx->key) {
944                 rx->key->tx_rx_count++;
945                 /* TODO: add threshold stuff again */
946         } else {
947                 return RX_DROP_MONITOR;
948         }
949
950         if (skb_linearize(rx->skb))
951                 return RX_DROP_UNUSABLE;
952         /* the hdr variable is invalid now! */
953
954         switch (rx->key->conf.alg) {
955         case ALG_WEP:
956                 /* Check for weak IVs if possible */
957                 if (rx->sta && ieee80211_is_data(fc) &&
958                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
959                      !(status->flag & RX_FLAG_DECRYPTED)) &&
960                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
961                         rx->sta->wep_weak_iv_count++;
962
963                 result = ieee80211_crypto_wep_decrypt(rx);
964                 break;
965         case ALG_TKIP:
966                 result = ieee80211_crypto_tkip_decrypt(rx);
967                 break;
968         case ALG_CCMP:
969                 result = ieee80211_crypto_ccmp_decrypt(rx);
970                 break;
971         case ALG_AES_CMAC:
972                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
973                 break;
974         }
975
976         /* either the frame has been decrypted or will be dropped */
977         status->flag |= RX_FLAG_DECRYPTED;
978
979         return result;
980 }
981
982 static ieee80211_rx_result debug_noinline
983 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
984 {
985         struct ieee80211_local *local;
986         struct ieee80211_hdr *hdr;
987         struct sk_buff *skb;
988
989         local = rx->local;
990         skb = rx->skb;
991         hdr = (struct ieee80211_hdr *) skb->data;
992
993         if (!local->pspolling)
994                 return RX_CONTINUE;
995
996         if (!ieee80211_has_fromds(hdr->frame_control))
997                 /* this is not from AP */
998                 return RX_CONTINUE;
999
1000         if (!ieee80211_is_data(hdr->frame_control))
1001                 return RX_CONTINUE;
1002
1003         if (!ieee80211_has_moredata(hdr->frame_control)) {
1004                 /* AP has no more frames buffered for us */
1005                 local->pspolling = false;
1006                 return RX_CONTINUE;
1007         }
1008
1009         /* more data bit is set, let's request a new frame from the AP */
1010         ieee80211_send_pspoll(local, rx->sdata);
1011
1012         return RX_CONTINUE;
1013 }
1014
1015 static void ap_sta_ps_start(struct sta_info *sta)
1016 {
1017         struct ieee80211_sub_if_data *sdata = sta->sdata;
1018         struct ieee80211_local *local = sdata->local;
1019
1020         atomic_inc(&sdata->bss->num_sta_ps);
1021         set_sta_flags(sta, WLAN_STA_PS_STA);
1022         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1023 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1024         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1025                sdata->name, sta->sta.addr, sta->sta.aid);
1026 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1027 }
1028
1029 static void ap_sta_ps_end(struct sta_info *sta)
1030 {
1031         struct ieee80211_sub_if_data *sdata = sta->sdata;
1032
1033         atomic_dec(&sdata->bss->num_sta_ps);
1034
1035         clear_sta_flags(sta, WLAN_STA_PS_STA);
1036
1037 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1038         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1039                sdata->name, sta->sta.addr, sta->sta.aid);
1040 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1041
1042         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1043 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1044                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1045                        sdata->name, sta->sta.addr, sta->sta.aid);
1046 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1047                 return;
1048         }
1049
1050         ieee80211_sta_ps_deliver_wakeup(sta);
1051 }
1052
1053 static ieee80211_rx_result debug_noinline
1054 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1055 {
1056         struct sta_info *sta = rx->sta;
1057         struct sk_buff *skb = rx->skb;
1058         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1059         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1060
1061         if (!sta)
1062                 return RX_CONTINUE;
1063
1064         /*
1065          * Update last_rx only for IBSS packets which are for the current
1066          * BSSID to avoid keeping the current IBSS network alive in cases
1067          * where other STAs start using different BSSID.
1068          */
1069         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1070                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1071                                                 NL80211_IFTYPE_ADHOC);
1072                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1073                         sta->last_rx = jiffies;
1074         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1075                 /*
1076                  * Mesh beacons will update last_rx when if they are found to
1077                  * match the current local configuration when processed.
1078                  */
1079                 sta->last_rx = jiffies;
1080         }
1081
1082         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1083                 return RX_CONTINUE;
1084
1085         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1086                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1087
1088         sta->rx_fragments++;
1089         sta->rx_bytes += rx->skb->len;
1090         sta->last_signal = status->signal;
1091
1092         /*
1093          * Change STA power saving mode only at the end of a frame
1094          * exchange sequence.
1095          */
1096         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1097             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1098              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1099                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1100                         /*
1101                          * Ignore doze->wake transitions that are
1102                          * indicated by non-data frames, the standard
1103                          * is unclear here, but for example going to
1104                          * PS mode and then scanning would cause a
1105                          * doze->wake transition for the probe request,
1106                          * and that is clearly undesirable.
1107                          */
1108                         if (ieee80211_is_data(hdr->frame_control) &&
1109                             !ieee80211_has_pm(hdr->frame_control))
1110                                 ap_sta_ps_end(sta);
1111                 } else {
1112                         if (ieee80211_has_pm(hdr->frame_control))
1113                                 ap_sta_ps_start(sta);
1114                 }
1115         }
1116
1117         /*
1118          * Drop (qos-)data::nullfunc frames silently, since they
1119          * are used only to control station power saving mode.
1120          */
1121         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1122             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1123                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1124
1125                 /*
1126                  * If we receive a 4-addr nullfunc frame from a STA
1127                  * that was not moved to a 4-addr STA vlan yet, drop
1128                  * the frame to the monitor interface, to make sure
1129                  * that hostapd sees it
1130                  */
1131                 if (ieee80211_has_a4(hdr->frame_control) &&
1132                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1133                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1134                       !rx->sdata->u.vlan.sta)))
1135                         return RX_DROP_MONITOR;
1136                 /*
1137                  * Update counter and free packet here to avoid
1138                  * counting this as a dropped packed.
1139                  */
1140                 sta->rx_packets++;
1141                 dev_kfree_skb(rx->skb);
1142                 return RX_QUEUED;
1143         }
1144
1145         return RX_CONTINUE;
1146 } /* ieee80211_rx_h_sta_process */
1147
1148 static inline struct ieee80211_fragment_entry *
1149 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1150                          unsigned int frag, unsigned int seq, int rx_queue,
1151                          struct sk_buff **skb)
1152 {
1153         struct ieee80211_fragment_entry *entry;
1154         int idx;
1155
1156         idx = sdata->fragment_next;
1157         entry = &sdata->fragments[sdata->fragment_next++];
1158         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1159                 sdata->fragment_next = 0;
1160
1161         if (!skb_queue_empty(&entry->skb_list)) {
1162 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1163                 struct ieee80211_hdr *hdr =
1164                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1165                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1166                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1167                        "addr1=%pM addr2=%pM\n",
1168                        sdata->name, idx,
1169                        jiffies - entry->first_frag_time, entry->seq,
1170                        entry->last_frag, hdr->addr1, hdr->addr2);
1171 #endif
1172                 __skb_queue_purge(&entry->skb_list);
1173         }
1174
1175         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1176         *skb = NULL;
1177         entry->first_frag_time = jiffies;
1178         entry->seq = seq;
1179         entry->rx_queue = rx_queue;
1180         entry->last_frag = frag;
1181         entry->ccmp = 0;
1182         entry->extra_len = 0;
1183
1184         return entry;
1185 }
1186
1187 static inline struct ieee80211_fragment_entry *
1188 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1189                           unsigned int frag, unsigned int seq,
1190                           int rx_queue, struct ieee80211_hdr *hdr)
1191 {
1192         struct ieee80211_fragment_entry *entry;
1193         int i, idx;
1194
1195         idx = sdata->fragment_next;
1196         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1197                 struct ieee80211_hdr *f_hdr;
1198
1199                 idx--;
1200                 if (idx < 0)
1201                         idx = IEEE80211_FRAGMENT_MAX - 1;
1202
1203                 entry = &sdata->fragments[idx];
1204                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1205                     entry->rx_queue != rx_queue ||
1206                     entry->last_frag + 1 != frag)
1207                         continue;
1208
1209                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1210
1211                 /*
1212                  * Check ftype and addresses are equal, else check next fragment
1213                  */
1214                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1215                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1216                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1217                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1218                         continue;
1219
1220                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1221                         __skb_queue_purge(&entry->skb_list);
1222                         continue;
1223                 }
1224                 return entry;
1225         }
1226
1227         return NULL;
1228 }
1229
1230 static ieee80211_rx_result debug_noinline
1231 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1232 {
1233         struct ieee80211_hdr *hdr;
1234         u16 sc;
1235         __le16 fc;
1236         unsigned int frag, seq;
1237         struct ieee80211_fragment_entry *entry;
1238         struct sk_buff *skb;
1239
1240         hdr = (struct ieee80211_hdr *)rx->skb->data;
1241         fc = hdr->frame_control;
1242         sc = le16_to_cpu(hdr->seq_ctrl);
1243         frag = sc & IEEE80211_SCTL_FRAG;
1244
1245         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1246                    (rx->skb)->len < 24 ||
1247                    is_multicast_ether_addr(hdr->addr1))) {
1248                 /* not fragmented */
1249                 goto out;
1250         }
1251         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1252
1253         if (skb_linearize(rx->skb))
1254                 return RX_DROP_UNUSABLE;
1255
1256         /*
1257          *  skb_linearize() might change the skb->data and
1258          *  previously cached variables (in this case, hdr) need to
1259          *  be refreshed with the new data.
1260          */
1261         hdr = (struct ieee80211_hdr *)rx->skb->data;
1262         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1263
1264         if (frag == 0) {
1265                 /* This is the first fragment of a new frame. */
1266                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1267                                                  rx->queue, &(rx->skb));
1268                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1269                     ieee80211_has_protected(fc)) {
1270                         /* Store CCMP PN so that we can verify that the next
1271                          * fragment has a sequential PN value. */
1272                         entry->ccmp = 1;
1273                         memcpy(entry->last_pn,
1274                                rx->key->u.ccmp.rx_pn[rx->queue],
1275                                CCMP_PN_LEN);
1276                 }
1277                 return RX_QUEUED;
1278         }
1279
1280         /* This is a fragment for a frame that should already be pending in
1281          * fragment cache. Add this fragment to the end of the pending entry.
1282          */
1283         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1284         if (!entry) {
1285                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1286                 return RX_DROP_MONITOR;
1287         }
1288
1289         /* Verify that MPDUs within one MSDU have sequential PN values.
1290          * (IEEE 802.11i, 8.3.3.4.5) */
1291         if (entry->ccmp) {
1292                 int i;
1293                 u8 pn[CCMP_PN_LEN], *rpn;
1294                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1295                         return RX_DROP_UNUSABLE;
1296                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1297                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1298                         pn[i]++;
1299                         if (pn[i])
1300                                 break;
1301                 }
1302                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1303                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1304                         return RX_DROP_UNUSABLE;
1305                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1306         }
1307
1308         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1309         __skb_queue_tail(&entry->skb_list, rx->skb);
1310         entry->last_frag = frag;
1311         entry->extra_len += rx->skb->len;
1312         if (ieee80211_has_morefrags(fc)) {
1313                 rx->skb = NULL;
1314                 return RX_QUEUED;
1315         }
1316
1317         rx->skb = __skb_dequeue(&entry->skb_list);
1318         if (skb_tailroom(rx->skb) < entry->extra_len) {
1319                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1320                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1321                                               GFP_ATOMIC))) {
1322                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1323                         __skb_queue_purge(&entry->skb_list);
1324                         return RX_DROP_UNUSABLE;
1325                 }
1326         }
1327         while ((skb = __skb_dequeue(&entry->skb_list))) {
1328                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1329                 dev_kfree_skb(skb);
1330         }
1331
1332         /* Complete frame has been reassembled - process it now */
1333         rx->flags |= IEEE80211_RX_FRAGMENTED;
1334
1335  out:
1336         if (rx->sta)
1337                 rx->sta->rx_packets++;
1338         if (is_multicast_ether_addr(hdr->addr1))
1339                 rx->local->dot11MulticastReceivedFrameCount++;
1340         else
1341                 ieee80211_led_rx(rx->local);
1342         return RX_CONTINUE;
1343 }
1344
1345 static ieee80211_rx_result debug_noinline
1346 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1347 {
1348         struct ieee80211_sub_if_data *sdata = rx->sdata;
1349         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1350
1351         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1352                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1353                 return RX_CONTINUE;
1354
1355         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1356             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1357                 return RX_DROP_UNUSABLE;
1358
1359         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1360                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1361         else
1362                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1363
1364         /* Free PS Poll skb here instead of returning RX_DROP that would
1365          * count as an dropped frame. */
1366         dev_kfree_skb(rx->skb);
1367
1368         return RX_QUEUED;
1369 }
1370
1371 static ieee80211_rx_result debug_noinline
1372 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1373 {
1374         u8 *data = rx->skb->data;
1375         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1376
1377         if (!ieee80211_is_data_qos(hdr->frame_control))
1378                 return RX_CONTINUE;
1379
1380         /* remove the qos control field, update frame type and meta-data */
1381         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1382                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1383         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1384         /* change frame type to non QOS */
1385         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1386
1387         return RX_CONTINUE;
1388 }
1389
1390 static int
1391 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1392 {
1393         if (unlikely(!rx->sta ||
1394             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1395                 return -EACCES;
1396
1397         return 0;
1398 }
1399
1400 static int
1401 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1402 {
1403         struct sk_buff *skb = rx->skb;
1404         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1405
1406         /*
1407          * Pass through unencrypted frames if the hardware has
1408          * decrypted them already.
1409          */
1410         if (status->flag & RX_FLAG_DECRYPTED)
1411                 return 0;
1412
1413         /* Drop unencrypted frames if key is set. */
1414         if (unlikely(!ieee80211_has_protected(fc) &&
1415                      !ieee80211_is_nullfunc(fc) &&
1416                      ieee80211_is_data(fc) &&
1417                      (rx->key || rx->sdata->drop_unencrypted)))
1418                 return -EACCES;
1419
1420         return 0;
1421 }
1422
1423 static int
1424 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1425 {
1426         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1427         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1428         __le16 fc = hdr->frame_control;
1429
1430         /*
1431          * Pass through unencrypted frames if the hardware has
1432          * decrypted them already.
1433          */
1434         if (status->flag & RX_FLAG_DECRYPTED)
1435                 return 0;
1436
1437         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1438                 if (unlikely(!ieee80211_has_protected(fc) &&
1439                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1440                              rx->key))
1441                         return -EACCES;
1442                 /* BIP does not use Protected field, so need to check MMIE */
1443                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1444                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1445                         return -EACCES;
1446                 /*
1447                  * When using MFP, Action frames are not allowed prior to
1448                  * having configured keys.
1449                  */
1450                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1451                              ieee80211_is_robust_mgmt_frame(
1452                                      (struct ieee80211_hdr *) rx->skb->data)))
1453                         return -EACCES;
1454         }
1455
1456         return 0;
1457 }
1458
1459 static int
1460 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1461 {
1462         struct ieee80211_sub_if_data *sdata = rx->sdata;
1463         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1464
1465         if (ieee80211_has_a4(hdr->frame_control) &&
1466             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1467                 return -1;
1468
1469         if (is_multicast_ether_addr(hdr->addr1) &&
1470             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1471              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1472                 return -1;
1473
1474         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1475 }
1476
1477 /*
1478  * requires that rx->skb is a frame with ethernet header
1479  */
1480 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1481 {
1482         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1483                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1484         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1485
1486         /*
1487          * Allow EAPOL frames to us/the PAE group address regardless
1488          * of whether the frame was encrypted or not.
1489          */
1490         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1491             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1492              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1493                 return true;
1494
1495         if (ieee80211_802_1x_port_control(rx) ||
1496             ieee80211_drop_unencrypted(rx, fc))
1497                 return false;
1498
1499         return true;
1500 }
1501
1502 /*
1503  * requires that rx->skb is a frame with ethernet header
1504  */
1505 static void
1506 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1507 {
1508         struct ieee80211_sub_if_data *sdata = rx->sdata;
1509         struct net_device *dev = sdata->dev;
1510         struct sk_buff *skb, *xmit_skb;
1511         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1512         struct sta_info *dsta;
1513
1514         skb = rx->skb;
1515         xmit_skb = NULL;
1516
1517         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1518              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1519             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1520             (rx->flags & IEEE80211_RX_RA_MATCH) &&
1521             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1522                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1523                         /*
1524                          * send multicast frames both to higher layers in
1525                          * local net stack and back to the wireless medium
1526                          */
1527                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1528                         if (!xmit_skb && net_ratelimit())
1529                                 printk(KERN_DEBUG "%s: failed to clone "
1530                                        "multicast frame\n", dev->name);
1531                 } else {
1532                         dsta = sta_info_get(sdata, skb->data);
1533                         if (dsta) {
1534                                 /*
1535                                  * The destination station is associated to
1536                                  * this AP (in this VLAN), so send the frame
1537                                  * directly to it and do not pass it to local
1538                                  * net stack.
1539                                  */
1540                                 xmit_skb = skb;
1541                                 skb = NULL;
1542                         }
1543                 }
1544         }
1545
1546         if (skb) {
1547                 int align __maybe_unused;
1548
1549 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1550                 /*
1551                  * 'align' will only take the values 0 or 2 here
1552                  * since all frames are required to be aligned
1553                  * to 2-byte boundaries when being passed to
1554                  * mac80211. That also explains the __skb_push()
1555                  * below.
1556                  */
1557                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1558                 if (align) {
1559                         if (WARN_ON(skb_headroom(skb) < 3)) {
1560                                 dev_kfree_skb(skb);
1561                                 skb = NULL;
1562                         } else {
1563                                 u8 *data = skb->data;
1564                                 size_t len = skb_headlen(skb);
1565                                 skb->data -= align;
1566                                 memmove(skb->data, data, len);
1567                                 skb_set_tail_pointer(skb, len);
1568                         }
1569                 }
1570 #endif
1571
1572                 if (skb) {
1573                         /* deliver to local stack */
1574                         skb->protocol = eth_type_trans(skb, dev);
1575                         memset(skb->cb, 0, sizeof(skb->cb));
1576                         netif_rx(skb);
1577                 }
1578         }
1579
1580         if (xmit_skb) {
1581                 /* send to wireless media */
1582                 xmit_skb->protocol = htons(ETH_P_802_3);
1583                 skb_reset_network_header(xmit_skb);
1584                 skb_reset_mac_header(xmit_skb);
1585                 dev_queue_xmit(xmit_skb);
1586         }
1587 }
1588
1589 static ieee80211_rx_result debug_noinline
1590 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1591 {
1592         struct net_device *dev = rx->sdata->dev;
1593         struct sk_buff *skb = rx->skb;
1594         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1595         __le16 fc = hdr->frame_control;
1596         struct sk_buff_head frame_list;
1597
1598         if (unlikely(!ieee80211_is_data(fc)))
1599                 return RX_CONTINUE;
1600
1601         if (unlikely(!ieee80211_is_data_present(fc)))
1602                 return RX_DROP_MONITOR;
1603
1604         if (!(rx->flags & IEEE80211_RX_AMSDU))
1605                 return RX_CONTINUE;
1606
1607         if (ieee80211_has_a4(hdr->frame_control) &&
1608             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1609             !rx->sdata->u.vlan.sta)
1610                 return RX_DROP_UNUSABLE;
1611
1612         if (is_multicast_ether_addr(hdr->addr1) &&
1613             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1614               rx->sdata->u.vlan.sta) ||
1615              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1616               rx->sdata->u.mgd.use_4addr)))
1617                 return RX_DROP_UNUSABLE;
1618
1619         skb->dev = dev;
1620         __skb_queue_head_init(&frame_list);
1621
1622         if (skb_linearize(skb))
1623                 return RX_DROP_UNUSABLE;
1624
1625         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1626                                  rx->sdata->vif.type,
1627                                  rx->local->hw.extra_tx_headroom);
1628
1629         while (!skb_queue_empty(&frame_list)) {
1630                 rx->skb = __skb_dequeue(&frame_list);
1631
1632                 if (!ieee80211_frame_allowed(rx, fc)) {
1633                         dev_kfree_skb(rx->skb);
1634                         continue;
1635                 }
1636                 dev->stats.rx_packets++;
1637                 dev->stats.rx_bytes += rx->skb->len;
1638
1639                 ieee80211_deliver_skb(rx);
1640         }
1641
1642         return RX_QUEUED;
1643 }
1644
1645 #ifdef CONFIG_MAC80211_MESH
1646 static ieee80211_rx_result
1647 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1648 {
1649         struct ieee80211_hdr *hdr;
1650         struct ieee80211s_hdr *mesh_hdr;
1651         unsigned int hdrlen;
1652         struct sk_buff *skb = rx->skb, *fwd_skb;
1653         struct ieee80211_local *local = rx->local;
1654         struct ieee80211_sub_if_data *sdata = rx->sdata;
1655
1656         hdr = (struct ieee80211_hdr *) skb->data;
1657         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1658         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1659
1660         if (!ieee80211_is_data(hdr->frame_control))
1661                 return RX_CONTINUE;
1662
1663         if (!mesh_hdr->ttl)
1664                 /* illegal frame */
1665                 return RX_DROP_MONITOR;
1666
1667         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1668                 struct mesh_path *mppath;
1669                 char *proxied_addr;
1670                 char *mpp_addr;
1671
1672                 if (is_multicast_ether_addr(hdr->addr1)) {
1673                         mpp_addr = hdr->addr3;
1674                         proxied_addr = mesh_hdr->eaddr1;
1675                 } else {
1676                         mpp_addr = hdr->addr4;
1677                         proxied_addr = mesh_hdr->eaddr2;
1678                 }
1679
1680                 rcu_read_lock();
1681                 mppath = mpp_path_lookup(proxied_addr, sdata);
1682                 if (!mppath) {
1683                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1684                 } else {
1685                         spin_lock_bh(&mppath->state_lock);
1686                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1687                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1688                         spin_unlock_bh(&mppath->state_lock);
1689                 }
1690                 rcu_read_unlock();
1691         }
1692
1693         /* Frame has reached destination.  Don't forward */
1694         if (!is_multicast_ether_addr(hdr->addr1) &&
1695             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1696                 return RX_CONTINUE;
1697
1698         mesh_hdr->ttl--;
1699
1700         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1701                 if (!mesh_hdr->ttl)
1702                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1703                                                      dropped_frames_ttl);
1704                 else {
1705                         struct ieee80211_hdr *fwd_hdr;
1706                         struct ieee80211_tx_info *info;
1707
1708                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1709
1710                         if (!fwd_skb && net_ratelimit())
1711                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1712                                                    sdata->name);
1713
1714                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1715                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1716                         info = IEEE80211_SKB_CB(fwd_skb);
1717                         memset(info, 0, sizeof(*info));
1718                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1719                         info->control.vif = &rx->sdata->vif;
1720                         skb_set_queue_mapping(skb,
1721                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1722                         ieee80211_set_qos_hdr(local, skb);
1723                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1724                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1725                                                                 fwded_mcast);
1726                         else {
1727                                 int err;
1728                                 /*
1729                                  * Save TA to addr1 to send TA a path error if a
1730                                  * suitable next hop is not found
1731                                  */
1732                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1733                                                 ETH_ALEN);
1734                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1735                                 /* Failed to immediately resolve next hop:
1736                                  * fwded frame was dropped or will be added
1737                                  * later to the pending skb queue.  */
1738                                 if (err)
1739                                         return RX_DROP_MONITOR;
1740
1741                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1742                                                                 fwded_unicast);
1743                         }
1744                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1745                                                      fwded_frames);
1746                         ieee80211_add_pending_skb(local, fwd_skb);
1747                 }
1748         }
1749
1750         if (is_multicast_ether_addr(hdr->addr1) ||
1751             sdata->dev->flags & IFF_PROMISC)
1752                 return RX_CONTINUE;
1753         else
1754                 return RX_DROP_MONITOR;
1755 }
1756 #endif
1757
1758 static ieee80211_rx_result debug_noinline
1759 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1760 {
1761         struct ieee80211_sub_if_data *sdata = rx->sdata;
1762         struct ieee80211_local *local = rx->local;
1763         struct net_device *dev = sdata->dev;
1764         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1765         __le16 fc = hdr->frame_control;
1766         int err;
1767
1768         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1769                 return RX_CONTINUE;
1770
1771         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1772                 return RX_DROP_MONITOR;
1773
1774         /*
1775          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1776          * that a 4-addr station can be detected and moved into a separate VLAN
1777          */
1778         if (ieee80211_has_a4(hdr->frame_control) &&
1779             sdata->vif.type == NL80211_IFTYPE_AP)
1780                 return RX_DROP_MONITOR;
1781
1782         err = __ieee80211_data_to_8023(rx);
1783         if (unlikely(err))
1784                 return RX_DROP_UNUSABLE;
1785
1786         if (!ieee80211_frame_allowed(rx, fc))
1787                 return RX_DROP_MONITOR;
1788
1789         rx->skb->dev = dev;
1790
1791         dev->stats.rx_packets++;
1792         dev->stats.rx_bytes += rx->skb->len;
1793
1794         if (ieee80211_is_data(hdr->frame_control) &&
1795             !is_multicast_ether_addr(hdr->addr1) &&
1796             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1797                         mod_timer(&local->dynamic_ps_timer, jiffies +
1798                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1799         }
1800
1801         ieee80211_deliver_skb(rx);
1802
1803         return RX_QUEUED;
1804 }
1805
1806 static ieee80211_rx_result debug_noinline
1807 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1808 {
1809         struct ieee80211_local *local = rx->local;
1810         struct ieee80211_hw *hw = &local->hw;
1811         struct sk_buff *skb = rx->skb;
1812         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1813         struct tid_ampdu_rx *tid_agg_rx;
1814         u16 start_seq_num;
1815         u16 tid;
1816
1817         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1818                 return RX_CONTINUE;
1819
1820         if (ieee80211_is_back_req(bar->frame_control)) {
1821                 struct {
1822                         __le16 control, start_seq_num;
1823                 } __packed bar_data;
1824
1825                 if (!rx->sta)
1826                         return RX_DROP_MONITOR;
1827
1828                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1829                                   &bar_data, sizeof(bar_data)))
1830                         return RX_DROP_MONITOR;
1831
1832                 spin_lock(&rx->sta->lock);
1833                 tid = le16_to_cpu(bar_data.control) >> 12;
1834                 if (!rx->sta->ampdu_mlme.tid_active_rx[tid]) {
1835                         spin_unlock(&rx->sta->lock);
1836                         return RX_DROP_MONITOR;
1837                 }
1838                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1839
1840                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1841
1842                 /* reset session timer */
1843                 if (tid_agg_rx->timeout)
1844                         mod_timer(&tid_agg_rx->session_timer,
1845                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1846
1847                 /* release stored frames up to start of BAR */
1848                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1849                                                  frames);
1850                 kfree_skb(skb);
1851                 spin_unlock(&rx->sta->lock);
1852                 return RX_QUEUED;
1853         }
1854
1855         /*
1856          * After this point, we only want management frames,
1857          * so we can drop all remaining control frames to
1858          * cooked monitor interfaces.
1859          */
1860         return RX_DROP_MONITOR;
1861 }
1862
1863 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1864                                            struct ieee80211_mgmt *mgmt,
1865                                            size_t len)
1866 {
1867         struct ieee80211_local *local = sdata->local;
1868         struct sk_buff *skb;
1869         struct ieee80211_mgmt *resp;
1870
1871         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1872                 /* Not to own unicast address */
1873                 return;
1874         }
1875
1876         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1877             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1878                 /* Not from the current AP or not associated yet. */
1879                 return;
1880         }
1881
1882         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1883                 /* Too short SA Query request frame */
1884                 return;
1885         }
1886
1887         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1888         if (skb == NULL)
1889                 return;
1890
1891         skb_reserve(skb, local->hw.extra_tx_headroom);
1892         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1893         memset(resp, 0, 24);
1894         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1895         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1896         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1897         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1898                                           IEEE80211_STYPE_ACTION);
1899         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1900         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1901         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1902         memcpy(resp->u.action.u.sa_query.trans_id,
1903                mgmt->u.action.u.sa_query.trans_id,
1904                WLAN_SA_QUERY_TR_ID_LEN);
1905
1906         ieee80211_tx_skb(sdata, skb);
1907 }
1908
1909 static ieee80211_rx_result debug_noinline
1910 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1911 {
1912         struct ieee80211_local *local = rx->local;
1913         struct ieee80211_sub_if_data *sdata = rx->sdata;
1914         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1915         struct sk_buff *nskb;
1916         struct ieee80211_rx_status *status;
1917         int len = rx->skb->len;
1918
1919         if (!ieee80211_is_action(mgmt->frame_control))
1920                 return RX_CONTINUE;
1921
1922         /* drop too small frames */
1923         if (len < IEEE80211_MIN_ACTION_SIZE)
1924                 return RX_DROP_UNUSABLE;
1925
1926         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
1927                 return RX_DROP_UNUSABLE;
1928
1929         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1930                 return RX_DROP_UNUSABLE;
1931
1932         if (ieee80211_drop_unencrypted_mgmt(rx))
1933                 return RX_DROP_UNUSABLE;
1934
1935         switch (mgmt->u.action.category) {
1936         case WLAN_CATEGORY_BACK:
1937                 /*
1938                  * The aggregation code is not prepared to handle
1939                  * anything but STA/AP due to the BSSID handling;
1940                  * IBSS could work in the code but isn't supported
1941                  * by drivers or the standard.
1942                  */
1943                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1944                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1945                     sdata->vif.type != NL80211_IFTYPE_AP)
1946                         break;
1947
1948                 /* verify action_code is present */
1949                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1950                         break;
1951
1952                 switch (mgmt->u.action.u.addba_req.action_code) {
1953                 case WLAN_ACTION_ADDBA_REQ:
1954                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1955                                    sizeof(mgmt->u.action.u.addba_req)))
1956                                 goto invalid;
1957                         break;
1958                 case WLAN_ACTION_ADDBA_RESP:
1959                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1960                                    sizeof(mgmt->u.action.u.addba_resp)))
1961                                 goto invalid;
1962                         break;
1963                 case WLAN_ACTION_DELBA:
1964                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1965                                    sizeof(mgmt->u.action.u.delba)))
1966                                 goto invalid;
1967                         break;
1968                 default:
1969                         goto invalid;
1970                 }
1971
1972                 skb_queue_tail(&sdata->skb_queue, rx->skb);
1973                 ieee80211_queue_work(&local->hw, &sdata->work);
1974                 return RX_QUEUED;
1975         case WLAN_CATEGORY_SPECTRUM_MGMT:
1976                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1977                         break;
1978
1979                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1980                         break;
1981
1982                 /* verify action_code is present */
1983                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1984                         break;
1985
1986                 switch (mgmt->u.action.u.measurement.action_code) {
1987                 case WLAN_ACTION_SPCT_MSR_REQ:
1988                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1989                                    sizeof(mgmt->u.action.u.measurement)))
1990                                 break;
1991                         ieee80211_process_measurement_req(sdata, mgmt, len);
1992                         goto handled;
1993                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1994                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1995                                    sizeof(mgmt->u.action.u.chan_switch)))
1996                                 break;
1997
1998                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1999                                 break;
2000
2001                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2002                                 break;
2003
2004                         skb_queue_tail(&sdata->skb_queue, rx->skb);
2005                         ieee80211_queue_work(&local->hw, &sdata->work);
2006                         return RX_QUEUED;
2007                 }
2008                 break;
2009         case WLAN_CATEGORY_SA_QUERY:
2010                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2011                            sizeof(mgmt->u.action.u.sa_query)))
2012                         break;
2013
2014                 switch (mgmt->u.action.u.sa_query.action) {
2015                 case WLAN_ACTION_SA_QUERY_REQUEST:
2016                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2017                                 break;
2018                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2019                         goto handled;
2020                 }
2021                 break;
2022         case WLAN_CATEGORY_MESH_PLINK:
2023         case WLAN_CATEGORY_MESH_PATH_SEL:
2024                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2025                         break;
2026                 skb_queue_tail(&sdata->skb_queue, rx->skb);
2027                 ieee80211_queue_work(&local->hw, &sdata->work);
2028                 return RX_QUEUED;
2029         }
2030
2031  invalid:
2032         /*
2033          * For AP mode, hostapd is responsible for handling any action
2034          * frames that we didn't handle, including returning unknown
2035          * ones. For all other modes we will return them to the sender,
2036          * setting the 0x80 bit in the action category, as required by
2037          * 802.11-2007 7.3.1.11.
2038          */
2039         if (sdata->vif.type == NL80211_IFTYPE_AP ||
2040             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2041                 return RX_DROP_MONITOR;
2042
2043         /*
2044          * Getting here means the kernel doesn't know how to handle
2045          * it, but maybe userspace does ... include returned frames
2046          * so userspace can register for those to know whether ones
2047          * it transmitted were processed or returned.
2048          */
2049         status = IEEE80211_SKB_RXCB(rx->skb);
2050
2051         if (cfg80211_rx_action(rx->sdata->dev, status->freq,
2052                                rx->skb->data, rx->skb->len,
2053                                GFP_ATOMIC))
2054                 goto handled;
2055
2056         /* do not return rejected action frames */
2057         if (mgmt->u.action.category & 0x80)
2058                 return RX_DROP_UNUSABLE;
2059
2060         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2061                                GFP_ATOMIC);
2062         if (nskb) {
2063                 struct ieee80211_mgmt *mgmt = (void *)nskb->data;
2064
2065                 mgmt->u.action.category |= 0x80;
2066                 memcpy(mgmt->da, mgmt->sa, ETH_ALEN);
2067                 memcpy(mgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2068
2069                 memset(nskb->cb, 0, sizeof(nskb->cb));
2070
2071                 ieee80211_tx_skb(rx->sdata, nskb);
2072         }
2073
2074  handled:
2075         if (rx->sta)
2076                 rx->sta->rx_packets++;
2077         dev_kfree_skb(rx->skb);
2078         return RX_QUEUED;
2079 }
2080
2081 static ieee80211_rx_result debug_noinline
2082 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2083 {
2084         struct ieee80211_sub_if_data *sdata = rx->sdata;
2085         ieee80211_rx_result rxs;
2086         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2087         __le16 stype;
2088
2089         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
2090                 return RX_DROP_MONITOR;
2091
2092         if (rx->skb->len < 24)
2093                 return RX_DROP_MONITOR;
2094
2095         if (ieee80211_drop_unencrypted_mgmt(rx))
2096                 return RX_DROP_UNUSABLE;
2097
2098         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2099         if (rxs != RX_CONTINUE)
2100                 return rxs;
2101
2102         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2103
2104         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2105             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2106             sdata->vif.type != NL80211_IFTYPE_STATION)
2107                 return RX_DROP_MONITOR;
2108
2109         switch (stype) {
2110         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2111         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2112                 /* process for all: mesh, mlme, ibss */
2113                 break;
2114         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2115         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2116                 /* process only for station */
2117                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2118                         return RX_DROP_MONITOR;
2119                 break;
2120         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2121         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2122                 /* process only for ibss */
2123                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2124                         return RX_DROP_MONITOR;
2125                 break;
2126         default:
2127                 return RX_DROP_MONITOR;
2128         }
2129
2130         /* queue up frame and kick off work to process it */
2131         skb_queue_tail(&sdata->skb_queue, rx->skb);
2132         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2133
2134         return RX_QUEUED;
2135 }
2136
2137 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2138                                             struct ieee80211_rx_data *rx)
2139 {
2140         int keyidx;
2141         unsigned int hdrlen;
2142
2143         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2144         if (rx->skb->len >= hdrlen + 4)
2145                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2146         else
2147                 keyidx = -1;
2148
2149         if (!rx->sta) {
2150                 /*
2151                  * Some hardware seem to generate incorrect Michael MIC
2152                  * reports; ignore them to avoid triggering countermeasures.
2153                  */
2154                 return;
2155         }
2156
2157         if (!ieee80211_has_protected(hdr->frame_control))
2158                 return;
2159
2160         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2161                 /*
2162                  * APs with pairwise keys should never receive Michael MIC
2163                  * errors for non-zero keyidx because these are reserved for
2164                  * group keys and only the AP is sending real multicast
2165                  * frames in the BSS.
2166                  */
2167                 return;
2168         }
2169
2170         if (!ieee80211_is_data(hdr->frame_control) &&
2171             !ieee80211_is_auth(hdr->frame_control))
2172                 return;
2173
2174         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2175                                         GFP_ATOMIC);
2176 }
2177
2178 /* TODO: use IEEE80211_RX_FRAGMENTED */
2179 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2180                                         struct ieee80211_rate *rate)
2181 {
2182         struct ieee80211_sub_if_data *sdata;
2183         struct ieee80211_local *local = rx->local;
2184         struct ieee80211_rtap_hdr {
2185                 struct ieee80211_radiotap_header hdr;
2186                 u8 flags;
2187                 u8 rate_or_pad;
2188                 __le16 chan_freq;
2189                 __le16 chan_flags;
2190         } __attribute__ ((packed)) *rthdr;
2191         struct sk_buff *skb = rx->skb, *skb2;
2192         struct net_device *prev_dev = NULL;
2193         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2194
2195         if (status->flag & RX_FLAG_INTERNAL_CMTR)
2196                 goto out_free_skb;
2197
2198         if (skb_headroom(skb) < sizeof(*rthdr) &&
2199             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2200                 goto out_free_skb;
2201
2202         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2203         memset(rthdr, 0, sizeof(*rthdr));
2204         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2205         rthdr->hdr.it_present =
2206                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2207                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2208
2209         if (rate) {
2210                 rthdr->rate_or_pad = rate->bitrate / 5;
2211                 rthdr->hdr.it_present |=
2212                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2213         }
2214         rthdr->chan_freq = cpu_to_le16(status->freq);
2215
2216         if (status->band == IEEE80211_BAND_5GHZ)
2217                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2218                                                 IEEE80211_CHAN_5GHZ);
2219         else
2220                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2221                                                 IEEE80211_CHAN_2GHZ);
2222
2223         skb_set_mac_header(skb, 0);
2224         skb->ip_summed = CHECKSUM_UNNECESSARY;
2225         skb->pkt_type = PACKET_OTHERHOST;
2226         skb->protocol = htons(ETH_P_802_2);
2227
2228         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2229                 if (!ieee80211_sdata_running(sdata))
2230                         continue;
2231
2232                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2233                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2234                         continue;
2235
2236                 if (prev_dev) {
2237                         skb2 = skb_clone(skb, GFP_ATOMIC);
2238                         if (skb2) {
2239                                 skb2->dev = prev_dev;
2240                                 netif_rx(skb2);
2241                         }
2242                 }
2243
2244                 prev_dev = sdata->dev;
2245                 sdata->dev->stats.rx_packets++;
2246                 sdata->dev->stats.rx_bytes += skb->len;
2247         }
2248
2249         if (prev_dev) {
2250                 skb->dev = prev_dev;
2251                 netif_rx(skb);
2252                 skb = NULL;
2253         } else
2254                 goto out_free_skb;
2255
2256         status->flag |= RX_FLAG_INTERNAL_CMTR;
2257         return;
2258
2259  out_free_skb:
2260         dev_kfree_skb(skb);
2261 }
2262
2263
2264 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2265                                          struct ieee80211_rx_data *rx,
2266                                          struct sk_buff *skb,
2267                                          struct ieee80211_rate *rate)
2268 {
2269         struct sk_buff_head reorder_release;
2270         ieee80211_rx_result res = RX_DROP_MONITOR;
2271
2272         __skb_queue_head_init(&reorder_release);
2273
2274         rx->skb = skb;
2275         rx->sdata = sdata;
2276
2277 #define CALL_RXH(rxh)                   \
2278         do {                            \
2279                 res = rxh(rx);          \
2280                 if (res != RX_CONTINUE) \
2281                         goto rxh_next;  \
2282         } while (0);
2283
2284         /*
2285          * NB: the rxh_next label works even if we jump
2286          *     to it from here because then the list will
2287          *     be empty, which is a trivial check
2288          */
2289         CALL_RXH(ieee80211_rx_h_passive_scan)
2290         CALL_RXH(ieee80211_rx_h_check)
2291
2292         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2293
2294         while ((skb = __skb_dequeue(&reorder_release))) {
2295                 /*
2296                  * all the other fields are valid across frames
2297                  * that belong to an aMPDU since they are on the
2298                  * same TID from the same station
2299                  */
2300                 rx->skb = skb;
2301
2302                 CALL_RXH(ieee80211_rx_h_decrypt)
2303                 CALL_RXH(ieee80211_rx_h_check_more_data)
2304                 CALL_RXH(ieee80211_rx_h_sta_process)
2305                 CALL_RXH(ieee80211_rx_h_defragment)
2306                 CALL_RXH(ieee80211_rx_h_ps_poll)
2307                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2308                 /* must be after MMIC verify so header is counted in MPDU mic */
2309                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2310                 CALL_RXH(ieee80211_rx_h_amsdu)
2311 #ifdef CONFIG_MAC80211_MESH
2312                 if (ieee80211_vif_is_mesh(&sdata->vif))
2313                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2314 #endif
2315                 CALL_RXH(ieee80211_rx_h_data)
2316
2317                 /* special treatment -- needs the queue */
2318                 res = ieee80211_rx_h_ctrl(rx, &reorder_release);
2319                 if (res != RX_CONTINUE)
2320                         goto rxh_next;
2321
2322                 CALL_RXH(ieee80211_rx_h_action)
2323                 CALL_RXH(ieee80211_rx_h_mgmt)
2324
2325 #undef CALL_RXH
2326
2327  rxh_next:
2328                 switch (res) {
2329                 case RX_DROP_MONITOR:
2330                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2331                         if (rx->sta)
2332                                 rx->sta->rx_dropped++;
2333                         /* fall through */
2334                 case RX_CONTINUE:
2335                         ieee80211_rx_cooked_monitor(rx, rate);
2336                         break;
2337                 case RX_DROP_UNUSABLE:
2338                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2339                         if (rx->sta)
2340                                 rx->sta->rx_dropped++;
2341                         dev_kfree_skb(rx->skb);
2342                         break;
2343                 case RX_QUEUED:
2344                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2345                         break;
2346                 }
2347         }
2348 }
2349
2350 /* main receive path */
2351
2352 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2353                                 struct ieee80211_rx_data *rx,
2354                                 struct ieee80211_hdr *hdr)
2355 {
2356         struct sk_buff *skb = rx->skb;
2357         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2358         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2359         int multicast = is_multicast_ether_addr(hdr->addr1);
2360
2361         switch (sdata->vif.type) {
2362         case NL80211_IFTYPE_STATION:
2363                 if (!bssid && !sdata->u.mgd.use_4addr)
2364                         return 0;
2365                 if (!multicast &&
2366                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2367                         if (!(sdata->dev->flags & IFF_PROMISC))
2368                                 return 0;
2369                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2370                 }
2371                 break;
2372         case NL80211_IFTYPE_ADHOC:
2373                 if (!bssid)
2374                         return 0;
2375                 if (ieee80211_is_beacon(hdr->frame_control)) {
2376                         return 1;
2377                 }
2378                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2379                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2380                                 return 0;
2381                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2382                 } else if (!multicast &&
2383                            compare_ether_addr(sdata->vif.addr,
2384                                               hdr->addr1) != 0) {
2385                         if (!(sdata->dev->flags & IFF_PROMISC))
2386                                 return 0;
2387                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2388                 } else if (!rx->sta) {
2389                         int rate_idx;
2390                         if (status->flag & RX_FLAG_HT)
2391                                 rate_idx = 0; /* TODO: HT rates */
2392                         else
2393                                 rate_idx = status->rate_idx;
2394                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2395                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2396                 }
2397                 break;
2398         case NL80211_IFTYPE_MESH_POINT:
2399                 if (!multicast &&
2400                     compare_ether_addr(sdata->vif.addr,
2401                                        hdr->addr1) != 0) {
2402                         if (!(sdata->dev->flags & IFF_PROMISC))
2403                                 return 0;
2404
2405                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2406                 }
2407                 break;
2408         case NL80211_IFTYPE_AP_VLAN:
2409         case NL80211_IFTYPE_AP:
2410                 if (!bssid) {
2411                         if (compare_ether_addr(sdata->vif.addr,
2412                                                hdr->addr1))
2413                                 return 0;
2414                 } else if (!ieee80211_bssid_match(bssid,
2415                                         sdata->vif.addr)) {
2416                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2417                                 return 0;
2418                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2419                 }
2420                 break;
2421         case NL80211_IFTYPE_WDS:
2422                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2423                         return 0;
2424                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2425                         return 0;
2426                 break;
2427         case NL80211_IFTYPE_MONITOR:
2428         case NL80211_IFTYPE_UNSPECIFIED:
2429         case __NL80211_IFTYPE_AFTER_LAST:
2430                 /* should never get here */
2431                 WARN_ON(1);
2432                 break;
2433         }
2434
2435         return 1;
2436 }
2437
2438 /*
2439  * This is the actual Rx frames handler. as it blongs to Rx path it must
2440  * be called with rcu_read_lock protection.
2441  */
2442 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2443                                          struct sk_buff *skb,
2444                                          struct ieee80211_rate *rate)
2445 {
2446         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2447         struct ieee80211_local *local = hw_to_local(hw);
2448         struct ieee80211_sub_if_data *sdata;
2449         struct ieee80211_hdr *hdr;
2450         __le16 fc;
2451         struct ieee80211_rx_data rx;
2452         int prepares;
2453         struct ieee80211_sub_if_data *prev = NULL;
2454         struct sk_buff *skb_new;
2455         struct sta_info *sta, *tmp;
2456         bool found_sta = false;
2457         int err = 0;
2458
2459         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2460         memset(&rx, 0, sizeof(rx));
2461         rx.skb = skb;
2462         rx.local = local;
2463
2464         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2465                 local->dot11ReceivedFragmentCount++;
2466
2467         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2468                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2469                 rx.flags |= IEEE80211_RX_IN_SCAN;
2470
2471         if (ieee80211_is_mgmt(fc))
2472                 err = skb_linearize(skb);
2473         else
2474                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2475
2476         if (err) {
2477                 dev_kfree_skb(skb);
2478                 return;
2479         }
2480
2481         hdr = (struct ieee80211_hdr *)skb->data;
2482         ieee80211_parse_qos(&rx);
2483         ieee80211_verify_alignment(&rx);
2484
2485         if (ieee80211_is_data(fc)) {
2486                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2487                         rx.sta = sta;
2488                         found_sta = true;
2489                         rx.sdata = sta->sdata;
2490
2491                         rx.flags |= IEEE80211_RX_RA_MATCH;
2492                         prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2493                         if (prepares) {
2494                                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2495                                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2496                                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2497                                 } else
2498                                         prev = rx.sdata;
2499                         }
2500                 }
2501         }
2502         if (!found_sta) {
2503                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2504                         if (!ieee80211_sdata_running(sdata))
2505                                 continue;
2506
2507                         if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2508                             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2509                                 continue;
2510
2511                         /*
2512                          * frame is destined for this interface, but if it's
2513                          * not also for the previous one we handle that after
2514                          * the loop to avoid copying the SKB once too much
2515                          */
2516
2517                         if (!prev) {
2518                                 prev = sdata;
2519                                 continue;
2520                         }
2521
2522                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2523
2524                         rx.flags |= IEEE80211_RX_RA_MATCH;
2525                         prepares = prepare_for_handlers(prev, &rx, hdr);
2526
2527                         if (!prepares)
2528                                 goto next;
2529
2530                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2531                                 rx.sdata = prev;
2532                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2533                                         ieee80211_rx_michael_mic_report(hdr,
2534                                                                         &rx);
2535                                 goto next;
2536                         }
2537
2538                         /*
2539                          * frame was destined for the previous interface
2540                          * so invoke RX handlers for it
2541                          */
2542
2543                         skb_new = skb_copy(skb, GFP_ATOMIC);
2544                         if (!skb_new) {
2545                                 if (net_ratelimit())
2546                                         printk(KERN_DEBUG "%s: failed to copy "
2547                                                "multicast frame for %s\n",
2548                                                wiphy_name(local->hw.wiphy),
2549                                                prev->name);
2550                                 goto next;
2551                         }
2552                         ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
2553 next:
2554                         prev = sdata;
2555                 }
2556
2557                 if (prev) {
2558                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2559
2560                         rx.flags |= IEEE80211_RX_RA_MATCH;
2561                         prepares = prepare_for_handlers(prev, &rx, hdr);
2562
2563                         if (!prepares)
2564                                 prev = NULL;
2565                 }
2566         }
2567         if (prev)
2568                 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate);
2569         else
2570                 dev_kfree_skb(skb);
2571 }
2572
2573 /*
2574  * This is the receive path handler. It is called by a low level driver when an
2575  * 802.11 MPDU is received from the hardware.
2576  */
2577 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2578 {
2579         struct ieee80211_local *local = hw_to_local(hw);
2580         struct ieee80211_rate *rate = NULL;
2581         struct ieee80211_supported_band *sband;
2582         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2583
2584         WARN_ON_ONCE(softirq_count() == 0);
2585
2586         if (WARN_ON(status->band < 0 ||
2587                     status->band >= IEEE80211_NUM_BANDS))
2588                 goto drop;
2589
2590         sband = local->hw.wiphy->bands[status->band];
2591         if (WARN_ON(!sband))
2592                 goto drop;
2593
2594         /*
2595          * If we're suspending, it is possible although not too likely
2596          * that we'd be receiving frames after having already partially
2597          * quiesced the stack. We can't process such frames then since
2598          * that might, for example, cause stations to be added or other
2599          * driver callbacks be invoked.
2600          */
2601         if (unlikely(local->quiescing || local->suspended))
2602                 goto drop;
2603
2604         /*
2605          * The same happens when we're not even started,
2606          * but that's worth a warning.
2607          */
2608         if (WARN_ON(!local->started))
2609                 goto drop;
2610
2611         if (status->flag & RX_FLAG_HT) {
2612                 /*
2613                  * rate_idx is MCS index, which can be [0-76] as documented on:
2614                  *
2615                  * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2616                  *
2617                  * Anything else would be some sort of driver or hardware error.
2618                  * The driver should catch hardware errors.
2619                  */
2620                 if (WARN((status->rate_idx < 0 ||
2621                          status->rate_idx > 76),
2622                          "Rate marked as an HT rate but passed "
2623                          "status->rate_idx is not "
2624                          "an MCS index [0-76]: %d (0x%02x)\n",
2625                          status->rate_idx,
2626                          status->rate_idx))
2627                         goto drop;
2628         } else {
2629                 if (WARN_ON(status->rate_idx < 0 ||
2630                             status->rate_idx >= sband->n_bitrates))
2631                         goto drop;
2632                 rate = &sband->bitrates[status->rate_idx];
2633         }
2634
2635         /*
2636          * key references and virtual interfaces are protected using RCU
2637          * and this requires that we are in a read-side RCU section during
2638          * receive processing
2639          */
2640         rcu_read_lock();
2641
2642         /*
2643          * Frames with failed FCS/PLCP checksum are not returned,
2644          * all other frames are returned without radiotap header
2645          * if it was previously present.
2646          * Also, frames with less than 16 bytes are dropped.
2647          */
2648         skb = ieee80211_rx_monitor(local, skb, rate);
2649         if (!skb) {
2650                 rcu_read_unlock();
2651                 return;
2652         }
2653
2654         __ieee80211_rx_handle_packet(hw, skb, rate);
2655
2656         rcu_read_unlock();
2657
2658         return;
2659  drop:
2660         kfree_skb(skb);
2661 }
2662 EXPORT_SYMBOL(ieee80211_rx);
2663
2664 /* This is a version of the rx handler that can be called from hard irq
2665  * context. Post the skb on the queue and schedule the tasklet */
2666 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2667 {
2668         struct ieee80211_local *local = hw_to_local(hw);
2669
2670         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2671
2672         skb->pkt_type = IEEE80211_RX_MSG;
2673         skb_queue_tail(&local->skb_queue, skb);
2674         tasklet_schedule(&local->tasklet);
2675 }
2676 EXPORT_SYMBOL(ieee80211_rx_irqsafe);