Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / net / mac80211 / rx.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/jiffies.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rcupdate.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20
21 #include "ieee80211_i.h"
22 #include "driver-ops.h"
23 #include "led.h"
24 #include "mesh.h"
25 #include "wep.h"
26 #include "wpa.h"
27 #include "tkip.h"
28 #include "wme.h"
29
30 /*
31  * monitor mode reception
32  *
33  * This function cleans up the SKB, i.e. it removes all the stuff
34  * only useful for monitoring.
35  */
36 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
37                                            struct sk_buff *skb)
38 {
39         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
40                 if (likely(skb->len > FCS_LEN))
41                         skb_trim(skb, skb->len - FCS_LEN);
42                 else {
43                         /* driver bug */
44                         WARN_ON(1);
45                         dev_kfree_skb(skb);
46                         skb = NULL;
47                 }
48         }
49
50         return skb;
51 }
52
53 static inline int should_drop_frame(struct sk_buff *skb,
54                                     int present_fcs_len)
55 {
56         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
57         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
58
59         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
60                 return 1;
61         if (unlikely(skb->len < 16 + present_fcs_len))
62                 return 1;
63         if (ieee80211_is_ctl(hdr->frame_control) &&
64             !ieee80211_is_pspoll(hdr->frame_control) &&
65             !ieee80211_is_back_req(hdr->frame_control))
66                 return 1;
67         return 0;
68 }
69
70 static int
71 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
72                           struct ieee80211_rx_status *status)
73 {
74         int len;
75
76         /* always present fields */
77         len = sizeof(struct ieee80211_radiotap_header) + 9;
78
79         if (status->flag & RX_FLAG_TSFT)
80                 len += 8;
81         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
82                 len += 1;
83         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
84                 len += 1;
85
86         if (len & 1) /* padding for RX_FLAGS if necessary */
87                 len++;
88
89         return len;
90 }
91
92 /*
93  * ieee80211_add_rx_radiotap_header - add radiotap header
94  *
95  * add a radiotap header containing all the fields which the hardware provided.
96  */
97 static void
98 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
99                                  struct sk_buff *skb,
100                                  struct ieee80211_rate *rate,
101                                  int rtap_len)
102 {
103         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
104         struct ieee80211_radiotap_header *rthdr;
105         unsigned char *pos;
106         u16 rx_flags = 0;
107
108         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
109         memset(rthdr, 0, rtap_len);
110
111         /* radiotap header, set always present flags */
112         rthdr->it_present =
113                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
114                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
115                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
116                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
117         rthdr->it_len = cpu_to_le16(rtap_len);
118
119         pos = (unsigned char *)(rthdr+1);
120
121         /* the order of the following fields is important */
122
123         /* IEEE80211_RADIOTAP_TSFT */
124         if (status->flag & RX_FLAG_TSFT) {
125                 put_unaligned_le64(status->mactime, pos);
126                 rthdr->it_present |=
127                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
128                 pos += 8;
129         }
130
131         /* IEEE80211_RADIOTAP_FLAGS */
132         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
133                 *pos |= IEEE80211_RADIOTAP_F_FCS;
134         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
135                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
136         if (status->flag & RX_FLAG_SHORTPRE)
137                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
138         pos++;
139
140         /* IEEE80211_RADIOTAP_RATE */
141         if (status->flag & RX_FLAG_HT) {
142                 /*
143                  * TODO: add following information into radiotap header once
144                  * suitable fields are defined for it:
145                  * - MCS index (status->rate_idx)
146                  * - HT40 (status->flag & RX_FLAG_40MHZ)
147                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
148                  */
149                 *pos = 0;
150         } else {
151                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
152                 *pos = rate->bitrate / 5;
153         }
154         pos++;
155
156         /* IEEE80211_RADIOTAP_CHANNEL */
157         put_unaligned_le16(status->freq, pos);
158         pos += 2;
159         if (status->band == IEEE80211_BAND_5GHZ)
160                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
161                                    pos);
162         else if (status->flag & RX_FLAG_HT)
163                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
164                                    pos);
165         else if (rate->flags & IEEE80211_RATE_ERP_G)
166                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
167                                    pos);
168         else
169                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
170                                    pos);
171         pos += 2;
172
173         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
174         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
175                 *pos = status->signal;
176                 rthdr->it_present |=
177                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
178                 pos++;
179         }
180
181         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
182         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
183                 *pos = status->noise;
184                 rthdr->it_present |=
185                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
186                 pos++;
187         }
188
189         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
190
191         /* IEEE80211_RADIOTAP_ANTENNA */
192         *pos = status->antenna;
193         pos++;
194
195         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
196
197         /* IEEE80211_RADIOTAP_RX_FLAGS */
198         /* ensure 2 byte alignment for the 2 byte field as required */
199         if ((pos - (u8 *)rthdr) & 1)
200                 pos++;
201         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
202                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
203         put_unaligned_le16(rx_flags, pos);
204         pos += 2;
205 }
206
207 /*
208  * This function copies a received frame to all monitor interfaces and
209  * returns a cleaned-up SKB that no longer includes the FCS nor the
210  * radiotap header the driver might have added.
211  */
212 static struct sk_buff *
213 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
214                      struct ieee80211_rate *rate)
215 {
216         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
217         struct ieee80211_sub_if_data *sdata;
218         int needed_headroom = 0;
219         struct sk_buff *skb, *skb2;
220         struct net_device *prev_dev = NULL;
221         int present_fcs_len = 0;
222
223         /*
224          * First, we may need to make a copy of the skb because
225          *  (1) we need to modify it for radiotap (if not present), and
226          *  (2) the other RX handlers will modify the skb we got.
227          *
228          * We don't need to, of course, if we aren't going to return
229          * the SKB because it has a bad FCS/PLCP checksum.
230          */
231
232         /* room for the radiotap header based on driver features */
233         needed_headroom = ieee80211_rx_radiotap_len(local, status);
234
235         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
236                 present_fcs_len = FCS_LEN;
237
238         if (!local->monitors) {
239                 if (should_drop_frame(origskb, present_fcs_len)) {
240                         dev_kfree_skb(origskb);
241                         return NULL;
242                 }
243
244                 return remove_monitor_info(local, origskb);
245         }
246
247         if (should_drop_frame(origskb, present_fcs_len)) {
248                 /* only need to expand headroom if necessary */
249                 skb = origskb;
250                 origskb = NULL;
251
252                 /*
253                  * This shouldn't trigger often because most devices have an
254                  * RX header they pull before we get here, and that should
255                  * be big enough for our radiotap information. We should
256                  * probably export the length to drivers so that we can have
257                  * them allocate enough headroom to start with.
258                  */
259                 if (skb_headroom(skb) < needed_headroom &&
260                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
261                         dev_kfree_skb(skb);
262                         return NULL;
263                 }
264         } else {
265                 /*
266                  * Need to make a copy and possibly remove radiotap header
267                  * and FCS from the original.
268                  */
269                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
270
271                 origskb = remove_monitor_info(local, origskb);
272
273                 if (!skb)
274                         return origskb;
275         }
276
277         /* prepend radiotap information */
278         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
279
280         skb_reset_mac_header(skb);
281         skb->ip_summed = CHECKSUM_UNNECESSARY;
282         skb->pkt_type = PACKET_OTHERHOST;
283         skb->protocol = htons(ETH_P_802_2);
284
285         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
286                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
287                         continue;
288
289                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
290                         continue;
291
292                 if (!ieee80211_sdata_running(sdata))
293                         continue;
294
295                 if (prev_dev) {
296                         skb2 = skb_clone(skb, GFP_ATOMIC);
297                         if (skb2) {
298                                 skb2->dev = prev_dev;
299                                 netif_rx(skb2);
300                         }
301                 }
302
303                 prev_dev = sdata->dev;
304                 sdata->dev->stats.rx_packets++;
305                 sdata->dev->stats.rx_bytes += skb->len;
306         }
307
308         if (prev_dev) {
309                 skb->dev = prev_dev;
310                 netif_rx(skb);
311         } else
312                 dev_kfree_skb(skb);
313
314         return origskb;
315 }
316
317
318 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
319 {
320         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
321         int tid;
322
323         /* does the frame have a qos control field? */
324         if (ieee80211_is_data_qos(hdr->frame_control)) {
325                 u8 *qc = ieee80211_get_qos_ctl(hdr);
326                 /* frame has qos control */
327                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
328                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
329                         rx->flags |= IEEE80211_RX_AMSDU;
330                 else
331                         rx->flags &= ~IEEE80211_RX_AMSDU;
332         } else {
333                 /*
334                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
335                  *
336                  *      Sequence numbers for management frames, QoS data
337                  *      frames with a broadcast/multicast address in the
338                  *      Address 1 field, and all non-QoS data frames sent
339                  *      by QoS STAs are assigned using an additional single
340                  *      modulo-4096 counter, [...]
341                  *
342                  * We also use that counter for non-QoS STAs.
343                  */
344                 tid = NUM_RX_DATA_QUEUES - 1;
345         }
346
347         rx->queue = tid;
348         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
349          * For now, set skb->priority to 0 for other cases. */
350         rx->skb->priority = (tid > 7) ? 0 : tid;
351 }
352
353 /**
354  * DOC: Packet alignment
355  *
356  * Drivers always need to pass packets that are aligned to two-byte boundaries
357  * to the stack.
358  *
359  * Additionally, should, if possible, align the payload data in a way that
360  * guarantees that the contained IP header is aligned to a four-byte
361  * boundary. In the case of regular frames, this simply means aligning the
362  * payload to a four-byte boundary (because either the IP header is directly
363  * contained, or IV/RFC1042 headers that have a length divisible by four are
364  * in front of it).  If the payload data is not properly aligned and the
365  * architecture doesn't support efficient unaligned operations, mac80211
366  * will align the data.
367  *
368  * With A-MSDU frames, however, the payload data address must yield two modulo
369  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
370  * push the IP header further back to a multiple of four again. Thankfully, the
371  * specs were sane enough this time around to require padding each A-MSDU
372  * subframe to a length that is a multiple of four.
373  *
374  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
375  * the payload is not supported, the driver is required to move the 802.11
376  * header to be directly in front of the payload in that case.
377  */
378 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
379 {
380 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
381         WARN_ONCE((unsigned long)rx->skb->data & 1,
382                   "unaligned packet at 0x%p\n", rx->skb->data);
383 #endif
384 }
385
386
387 /* rx handlers */
388
389 static ieee80211_rx_result debug_noinline
390 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
391 {
392         struct ieee80211_local *local = rx->local;
393         struct sk_buff *skb = rx->skb;
394
395         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
396                 return ieee80211_scan_rx(rx->sdata, skb);
397
398         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
399                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
400                 /* drop all the other packets during a software scan anyway */
401                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
402                         dev_kfree_skb(skb);
403                 return RX_QUEUED;
404         }
405
406         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
407                 /* scanning finished during invoking of handlers */
408                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
409                 return RX_DROP_UNUSABLE;
410         }
411
412         return RX_CONTINUE;
413 }
414
415
416 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
417 {
418         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
419
420         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
421                 return 0;
422
423         return ieee80211_is_robust_mgmt_frame(hdr);
424 }
425
426
427 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
428 {
429         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
430
431         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
432                 return 0;
433
434         return ieee80211_is_robust_mgmt_frame(hdr);
435 }
436
437
438 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
439 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
440 {
441         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
442         struct ieee80211_mmie *mmie;
443
444         if (skb->len < 24 + sizeof(*mmie) ||
445             !is_multicast_ether_addr(hdr->da))
446                 return -1;
447
448         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
449                 return -1; /* not a robust management frame */
450
451         mmie = (struct ieee80211_mmie *)
452                 (skb->data + skb->len - sizeof(*mmie));
453         if (mmie->element_id != WLAN_EID_MMIE ||
454             mmie->length != sizeof(*mmie) - 2)
455                 return -1;
456
457         return le16_to_cpu(mmie->key_id);
458 }
459
460
461 static ieee80211_rx_result
462 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
463 {
464         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
465         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
466         char *dev_addr = rx->sdata->vif.addr;
467
468         if (ieee80211_is_data(hdr->frame_control)) {
469                 if (is_multicast_ether_addr(hdr->addr1)) {
470                         if (ieee80211_has_tods(hdr->frame_control) ||
471                                 !ieee80211_has_fromds(hdr->frame_control))
472                                 return RX_DROP_MONITOR;
473                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
474                                 return RX_DROP_MONITOR;
475                 } else {
476                         if (!ieee80211_has_a4(hdr->frame_control))
477                                 return RX_DROP_MONITOR;
478                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
479                                 return RX_DROP_MONITOR;
480                 }
481         }
482
483         /* If there is not an established peer link and this is not a peer link
484          * establisment frame, beacon or probe, drop the frame.
485          */
486
487         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
488                 struct ieee80211_mgmt *mgmt;
489
490                 if (!ieee80211_is_mgmt(hdr->frame_control))
491                         return RX_DROP_MONITOR;
492
493                 if (ieee80211_is_action(hdr->frame_control)) {
494                         mgmt = (struct ieee80211_mgmt *)hdr;
495                         if (mgmt->u.action.category != MESH_PLINK_CATEGORY)
496                                 return RX_DROP_MONITOR;
497                         return RX_CONTINUE;
498                 }
499
500                 if (ieee80211_is_probe_req(hdr->frame_control) ||
501                     ieee80211_is_probe_resp(hdr->frame_control) ||
502                     ieee80211_is_beacon(hdr->frame_control))
503                         return RX_CONTINUE;
504
505                 return RX_DROP_MONITOR;
506
507         }
508
509 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
510
511         if (ieee80211_is_data(hdr->frame_control) &&
512             is_multicast_ether_addr(hdr->addr1) &&
513             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
514                 return RX_DROP_MONITOR;
515 #undef msh_h_get
516
517         return RX_CONTINUE;
518 }
519
520 #define SEQ_MODULO 0x1000
521 #define SEQ_MASK   0xfff
522
523 static inline int seq_less(u16 sq1, u16 sq2)
524 {
525         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
526 }
527
528 static inline u16 seq_inc(u16 sq)
529 {
530         return (sq + 1) & SEQ_MASK;
531 }
532
533 static inline u16 seq_sub(u16 sq1, u16 sq2)
534 {
535         return (sq1 - sq2) & SEQ_MASK;
536 }
537
538
539 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
540                                             struct tid_ampdu_rx *tid_agg_rx,
541                                             int index,
542                                             struct sk_buff_head *frames)
543 {
544         struct ieee80211_supported_band *sband;
545         struct ieee80211_rate *rate = NULL;
546         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
547         struct ieee80211_rx_status *status;
548
549         if (!skb)
550                 goto no_frame;
551
552         status = IEEE80211_SKB_RXCB(skb);
553
554         /* release the reordered frames to stack */
555         sband = hw->wiphy->bands[status->band];
556         if (!(status->flag & RX_FLAG_HT))
557                 rate = &sband->bitrates[status->rate_idx];
558         tid_agg_rx->stored_mpdu_num--;
559         tid_agg_rx->reorder_buf[index] = NULL;
560         __skb_queue_tail(frames, skb);
561
562 no_frame:
563         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
564 }
565
566 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
567                                              struct tid_ampdu_rx *tid_agg_rx,
568                                              u16 head_seq_num,
569                                              struct sk_buff_head *frames)
570 {
571         int index;
572
573         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
574                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
575                                                         tid_agg_rx->buf_size;
576                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
577         }
578 }
579
580 /*
581  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
582  * the skb was added to the buffer longer than this time ago, the earlier
583  * frames that have not yet been received are assumed to be lost and the skb
584  * can be released for processing. This may also release other skb's from the
585  * reorder buffer if there are no additional gaps between the frames.
586  */
587 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
588
589 /*
590  * As this function belongs to the RX path it must be under
591  * rcu_read_lock protection. It returns false if the frame
592  * can be processed immediately, true if it was consumed.
593  */
594 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
595                                              struct tid_ampdu_rx *tid_agg_rx,
596                                              struct sk_buff *skb,
597                                              struct sk_buff_head *frames)
598 {
599         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
600         u16 sc = le16_to_cpu(hdr->seq_ctrl);
601         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
602         u16 head_seq_num, buf_size;
603         int index;
604
605         buf_size = tid_agg_rx->buf_size;
606         head_seq_num = tid_agg_rx->head_seq_num;
607
608         /* frame with out of date sequence number */
609         if (seq_less(mpdu_seq_num, head_seq_num)) {
610                 dev_kfree_skb(skb);
611                 return true;
612         }
613
614         /*
615          * If frame the sequence number exceeds our buffering window
616          * size release some previous frames to make room for this one.
617          */
618         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
619                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
620                 /* release stored frames up to new head to stack */
621                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
622                                                  frames);
623         }
624
625         /* Now the new frame is always in the range of the reordering buffer */
626
627         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
628
629         /* check if we already stored this frame */
630         if (tid_agg_rx->reorder_buf[index]) {
631                 dev_kfree_skb(skb);
632                 return true;
633         }
634
635         /*
636          * If the current MPDU is in the right order and nothing else
637          * is stored we can process it directly, no need to buffer it.
638          */
639         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
640             tid_agg_rx->stored_mpdu_num == 0) {
641                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
642                 return false;
643         }
644
645         /* put the frame in the reordering buffer */
646         tid_agg_rx->reorder_buf[index] = skb;
647         tid_agg_rx->reorder_time[index] = jiffies;
648         tid_agg_rx->stored_mpdu_num++;
649         /* release the buffer until next missing frame */
650         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
651                                                 tid_agg_rx->buf_size;
652         if (!tid_agg_rx->reorder_buf[index] &&
653             tid_agg_rx->stored_mpdu_num > 1) {
654                 /*
655                  * No buffers ready to be released, but check whether any
656                  * frames in the reorder buffer have timed out.
657                  */
658                 int j;
659                 int skipped = 1;
660                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
661                      j = (j + 1) % tid_agg_rx->buf_size) {
662                         if (!tid_agg_rx->reorder_buf[j]) {
663                                 skipped++;
664                                 continue;
665                         }
666                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
667                                         HT_RX_REORDER_BUF_TIMEOUT))
668                                 break;
669
670 #ifdef CONFIG_MAC80211_HT_DEBUG
671                         if (net_ratelimit())
672                                 printk(KERN_DEBUG "%s: release an RX reorder "
673                                        "frame due to timeout on earlier "
674                                        "frames\n",
675                                        wiphy_name(hw->wiphy));
676 #endif
677                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
678                                                         j, frames);
679
680                         /*
681                          * Increment the head seq# also for the skipped slots.
682                          */
683                         tid_agg_rx->head_seq_num =
684                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
685                         skipped = 0;
686                 }
687         } else while (tid_agg_rx->reorder_buf[index]) {
688                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
689                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
690                                                         tid_agg_rx->buf_size;
691         }
692
693         return true;
694 }
695
696 /*
697  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
698  * true if the MPDU was buffered, false if it should be processed.
699  */
700 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
701                                        struct sk_buff_head *frames)
702 {
703         struct sk_buff *skb = rx->skb;
704         struct ieee80211_local *local = rx->local;
705         struct ieee80211_hw *hw = &local->hw;
706         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
707         struct sta_info *sta = rx->sta;
708         struct tid_ampdu_rx *tid_agg_rx;
709         u16 sc;
710         int tid;
711
712         if (!ieee80211_is_data_qos(hdr->frame_control))
713                 goto dont_reorder;
714
715         /*
716          * filter the QoS data rx stream according to
717          * STA/TID and check if this STA/TID is on aggregation
718          */
719
720         if (!sta)
721                 goto dont_reorder;
722
723         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
724
725         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
726                 goto dont_reorder;
727
728         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
729
730         /* qos null data frames are excluded */
731         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
732                 goto dont_reorder;
733
734         /* new, potentially un-ordered, ampdu frame - process it */
735
736         /* reset session timer */
737         if (tid_agg_rx->timeout)
738                 mod_timer(&tid_agg_rx->session_timer,
739                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
740
741         /* if this mpdu is fragmented - terminate rx aggregation session */
742         sc = le16_to_cpu(hdr->seq_ctrl);
743         if (sc & IEEE80211_SCTL_FRAG) {
744                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
745                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
746                 dev_kfree_skb(skb);
747                 return;
748         }
749
750         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
751                 return;
752
753  dont_reorder:
754         __skb_queue_tail(frames, skb);
755 }
756
757 static ieee80211_rx_result debug_noinline
758 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
759 {
760         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
761
762         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
763         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
764                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
765                              rx->sta->last_seq_ctrl[rx->queue] ==
766                              hdr->seq_ctrl)) {
767                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
768                                 rx->local->dot11FrameDuplicateCount++;
769                                 rx->sta->num_duplicates++;
770                         }
771                         return RX_DROP_MONITOR;
772                 } else
773                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
774         }
775
776         if (unlikely(rx->skb->len < 16)) {
777                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
778                 return RX_DROP_MONITOR;
779         }
780
781         /* Drop disallowed frame classes based on STA auth/assoc state;
782          * IEEE 802.11, Chap 5.5.
783          *
784          * mac80211 filters only based on association state, i.e. it drops
785          * Class 3 frames from not associated stations. hostapd sends
786          * deauth/disassoc frames when needed. In addition, hostapd is
787          * responsible for filtering on both auth and assoc states.
788          */
789
790         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
791                 return ieee80211_rx_mesh_check(rx);
792
793         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
794                       ieee80211_is_pspoll(hdr->frame_control)) &&
795                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
796                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
797                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
798                      !ieee80211_has_tods(hdr->frame_control) &&
799                      ieee80211_is_data(hdr->frame_control)) ||
800                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
801                         /* Drop IBSS frames and frames for other hosts
802                          * silently. */
803                         return RX_DROP_MONITOR;
804                 }
805
806                 return RX_DROP_MONITOR;
807         }
808
809         return RX_CONTINUE;
810 }
811
812
813 static ieee80211_rx_result debug_noinline
814 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
815 {
816         struct sk_buff *skb = rx->skb;
817         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
818         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
819         int keyidx;
820         int hdrlen;
821         ieee80211_rx_result result = RX_DROP_UNUSABLE;
822         struct ieee80211_key *stakey = NULL;
823         int mmie_keyidx = -1;
824
825         /*
826          * Key selection 101
827          *
828          * There are four types of keys:
829          *  - GTK (group keys)
830          *  - IGTK (group keys for management frames)
831          *  - PTK (pairwise keys)
832          *  - STK (station-to-station pairwise keys)
833          *
834          * When selecting a key, we have to distinguish between multicast
835          * (including broadcast) and unicast frames, the latter can only
836          * use PTKs and STKs while the former always use GTKs and IGTKs.
837          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
838          * unicast frames can also use key indices like GTKs. Hence, if we
839          * don't have a PTK/STK we check the key index for a WEP key.
840          *
841          * Note that in a regular BSS, multicast frames are sent by the
842          * AP only, associated stations unicast the frame to the AP first
843          * which then multicasts it on their behalf.
844          *
845          * There is also a slight problem in IBSS mode: GTKs are negotiated
846          * with each station, that is something we don't currently handle.
847          * The spec seems to expect that one negotiates the same key with
848          * every station but there's no such requirement; VLANs could be
849          * possible.
850          */
851
852         /*
853          * No point in finding a key and decrypting if the frame is neither
854          * addressed to us nor a multicast frame.
855          */
856         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
857                 return RX_CONTINUE;
858
859         /* start without a key */
860         rx->key = NULL;
861
862         if (rx->sta)
863                 stakey = rcu_dereference(rx->sta->key);
864
865         if (!ieee80211_has_protected(hdr->frame_control))
866                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
867
868         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
869                 rx->key = stakey;
870                 /* Skip decryption if the frame is not protected. */
871                 if (!ieee80211_has_protected(hdr->frame_control))
872                         return RX_CONTINUE;
873         } else if (mmie_keyidx >= 0) {
874                 /* Broadcast/multicast robust management frame / BIP */
875                 if ((status->flag & RX_FLAG_DECRYPTED) &&
876                     (status->flag & RX_FLAG_IV_STRIPPED))
877                         return RX_CONTINUE;
878
879                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
880                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
881                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
882                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
883         } else if (!ieee80211_has_protected(hdr->frame_control)) {
884                 /*
885                  * The frame was not protected, so skip decryption. However, we
886                  * need to set rx->key if there is a key that could have been
887                  * used so that the frame may be dropped if encryption would
888                  * have been expected.
889                  */
890                 struct ieee80211_key *key = NULL;
891                 if (ieee80211_is_mgmt(hdr->frame_control) &&
892                     is_multicast_ether_addr(hdr->addr1) &&
893                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
894                         rx->key = key;
895                 else if ((key = rcu_dereference(rx->sdata->default_key)))
896                         rx->key = key;
897                 return RX_CONTINUE;
898         } else {
899                 /*
900                  * The device doesn't give us the IV so we won't be
901                  * able to look up the key. That's ok though, we
902                  * don't need to decrypt the frame, we just won't
903                  * be able to keep statistics accurate.
904                  * Except for key threshold notifications, should
905                  * we somehow allow the driver to tell us which key
906                  * the hardware used if this flag is set?
907                  */
908                 if ((status->flag & RX_FLAG_DECRYPTED) &&
909                     (status->flag & RX_FLAG_IV_STRIPPED))
910                         return RX_CONTINUE;
911
912                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
913
914                 if (rx->skb->len < 8 + hdrlen)
915                         return RX_DROP_UNUSABLE; /* TODO: count this? */
916
917                 /*
918                  * no need to call ieee80211_wep_get_keyidx,
919                  * it verifies a bunch of things we've done already
920                  */
921                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
922
923                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
924
925                 /*
926                  * RSNA-protected unicast frames should always be sent with
927                  * pairwise or station-to-station keys, but for WEP we allow
928                  * using a key index as well.
929                  */
930                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
931                     !is_multicast_ether_addr(hdr->addr1))
932                         rx->key = NULL;
933         }
934
935         if (rx->key) {
936                 rx->key->tx_rx_count++;
937                 /* TODO: add threshold stuff again */
938         } else {
939                 return RX_DROP_MONITOR;
940         }
941
942         /* Check for weak IVs if possible */
943         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
944             ieee80211_is_data(hdr->frame_control) &&
945             (!(status->flag & RX_FLAG_IV_STRIPPED) ||
946              !(status->flag & RX_FLAG_DECRYPTED)) &&
947             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
948                 rx->sta->wep_weak_iv_count++;
949
950         switch (rx->key->conf.alg) {
951         case ALG_WEP:
952                 result = ieee80211_crypto_wep_decrypt(rx);
953                 break;
954         case ALG_TKIP:
955                 result = ieee80211_crypto_tkip_decrypt(rx);
956                 break;
957         case ALG_CCMP:
958                 result = ieee80211_crypto_ccmp_decrypt(rx);
959                 break;
960         case ALG_AES_CMAC:
961                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
962                 break;
963         }
964
965         /* either the frame has been decrypted or will be dropped */
966         status->flag |= RX_FLAG_DECRYPTED;
967
968         return result;
969 }
970
971 static ieee80211_rx_result debug_noinline
972 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
973 {
974         struct ieee80211_local *local;
975         struct ieee80211_hdr *hdr;
976         struct sk_buff *skb;
977
978         local = rx->local;
979         skb = rx->skb;
980         hdr = (struct ieee80211_hdr *) skb->data;
981
982         if (!local->pspolling)
983                 return RX_CONTINUE;
984
985         if (!ieee80211_has_fromds(hdr->frame_control))
986                 /* this is not from AP */
987                 return RX_CONTINUE;
988
989         if (!ieee80211_is_data(hdr->frame_control))
990                 return RX_CONTINUE;
991
992         if (!ieee80211_has_moredata(hdr->frame_control)) {
993                 /* AP has no more frames buffered for us */
994                 local->pspolling = false;
995                 return RX_CONTINUE;
996         }
997
998         /* more data bit is set, let's request a new frame from the AP */
999         ieee80211_send_pspoll(local, rx->sdata);
1000
1001         return RX_CONTINUE;
1002 }
1003
1004 static void ap_sta_ps_start(struct sta_info *sta)
1005 {
1006         struct ieee80211_sub_if_data *sdata = sta->sdata;
1007         struct ieee80211_local *local = sdata->local;
1008
1009         atomic_inc(&sdata->bss->num_sta_ps);
1010         set_sta_flags(sta, WLAN_STA_PS_STA);
1011         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1012 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1013         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1014                sdata->name, sta->sta.addr, sta->sta.aid);
1015 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1016 }
1017
1018 static void ap_sta_ps_end(struct sta_info *sta)
1019 {
1020         struct ieee80211_sub_if_data *sdata = sta->sdata;
1021
1022         atomic_dec(&sdata->bss->num_sta_ps);
1023
1024         clear_sta_flags(sta, WLAN_STA_PS_STA);
1025
1026 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1027         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1028                sdata->name, sta->sta.addr, sta->sta.aid);
1029 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1030
1031         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1032 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1033                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1034                        sdata->name, sta->sta.addr, sta->sta.aid);
1035 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1036                 return;
1037         }
1038
1039         ieee80211_sta_ps_deliver_wakeup(sta);
1040 }
1041
1042 static ieee80211_rx_result debug_noinline
1043 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1044 {
1045         struct sta_info *sta = rx->sta;
1046         struct sk_buff *skb = rx->skb;
1047         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1048         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1049
1050         if (!sta)
1051                 return RX_CONTINUE;
1052
1053         /*
1054          * Update last_rx only for IBSS packets which are for the current
1055          * BSSID to avoid keeping the current IBSS network alive in cases
1056          * where other STAs start using different BSSID.
1057          */
1058         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1059                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1060                                                 NL80211_IFTYPE_ADHOC);
1061                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1062                         sta->last_rx = jiffies;
1063         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1064                 /*
1065                  * Mesh beacons will update last_rx when if they are found to
1066                  * match the current local configuration when processed.
1067                  */
1068                 sta->last_rx = jiffies;
1069         }
1070
1071         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1072                 return RX_CONTINUE;
1073
1074         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1075                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1076
1077         sta->rx_fragments++;
1078         sta->rx_bytes += rx->skb->len;
1079         sta->last_signal = status->signal;
1080         sta->last_noise = status->noise;
1081
1082         /*
1083          * Change STA power saving mode only at the end of a frame
1084          * exchange sequence.
1085          */
1086         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1087             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1088              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1089                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1090                         /*
1091                          * Ignore doze->wake transitions that are
1092                          * indicated by non-data frames, the standard
1093                          * is unclear here, but for example going to
1094                          * PS mode and then scanning would cause a
1095                          * doze->wake transition for the probe request,
1096                          * and that is clearly undesirable.
1097                          */
1098                         if (ieee80211_is_data(hdr->frame_control) &&
1099                             !ieee80211_has_pm(hdr->frame_control))
1100                                 ap_sta_ps_end(sta);
1101                 } else {
1102                         if (ieee80211_has_pm(hdr->frame_control))
1103                                 ap_sta_ps_start(sta);
1104                 }
1105         }
1106
1107         /*
1108          * Drop (qos-)data::nullfunc frames silently, since they
1109          * are used only to control station power saving mode.
1110          */
1111         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1112             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1113                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1114
1115                 /*
1116                  * If we receive a 4-addr nullfunc frame from a STA
1117                  * that was not moved to a 4-addr STA vlan yet, drop
1118                  * the frame to the monitor interface, to make sure
1119                  * that hostapd sees it
1120                  */
1121                 if (ieee80211_has_a4(hdr->frame_control) &&
1122                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1123                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1124                       !rx->sdata->u.vlan.sta)))
1125                         return RX_DROP_MONITOR;
1126                 /*
1127                  * Update counter and free packet here to avoid
1128                  * counting this as a dropped packed.
1129                  */
1130                 sta->rx_packets++;
1131                 dev_kfree_skb(rx->skb);
1132                 return RX_QUEUED;
1133         }
1134
1135         return RX_CONTINUE;
1136 } /* ieee80211_rx_h_sta_process */
1137
1138 static inline struct ieee80211_fragment_entry *
1139 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1140                          unsigned int frag, unsigned int seq, int rx_queue,
1141                          struct sk_buff **skb)
1142 {
1143         struct ieee80211_fragment_entry *entry;
1144         int idx;
1145
1146         idx = sdata->fragment_next;
1147         entry = &sdata->fragments[sdata->fragment_next++];
1148         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1149                 sdata->fragment_next = 0;
1150
1151         if (!skb_queue_empty(&entry->skb_list)) {
1152 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1153                 struct ieee80211_hdr *hdr =
1154                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1155                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1156                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1157                        "addr1=%pM addr2=%pM\n",
1158                        sdata->name, idx,
1159                        jiffies - entry->first_frag_time, entry->seq,
1160                        entry->last_frag, hdr->addr1, hdr->addr2);
1161 #endif
1162                 __skb_queue_purge(&entry->skb_list);
1163         }
1164
1165         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1166         *skb = NULL;
1167         entry->first_frag_time = jiffies;
1168         entry->seq = seq;
1169         entry->rx_queue = rx_queue;
1170         entry->last_frag = frag;
1171         entry->ccmp = 0;
1172         entry->extra_len = 0;
1173
1174         return entry;
1175 }
1176
1177 static inline struct ieee80211_fragment_entry *
1178 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1179                           unsigned int frag, unsigned int seq,
1180                           int rx_queue, struct ieee80211_hdr *hdr)
1181 {
1182         struct ieee80211_fragment_entry *entry;
1183         int i, idx;
1184
1185         idx = sdata->fragment_next;
1186         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1187                 struct ieee80211_hdr *f_hdr;
1188
1189                 idx--;
1190                 if (idx < 0)
1191                         idx = IEEE80211_FRAGMENT_MAX - 1;
1192
1193                 entry = &sdata->fragments[idx];
1194                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1195                     entry->rx_queue != rx_queue ||
1196                     entry->last_frag + 1 != frag)
1197                         continue;
1198
1199                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1200
1201                 /*
1202                  * Check ftype and addresses are equal, else check next fragment
1203                  */
1204                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1205                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1206                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1207                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1208                         continue;
1209
1210                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1211                         __skb_queue_purge(&entry->skb_list);
1212                         continue;
1213                 }
1214                 return entry;
1215         }
1216
1217         return NULL;
1218 }
1219
1220 static ieee80211_rx_result debug_noinline
1221 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1222 {
1223         struct ieee80211_hdr *hdr;
1224         u16 sc;
1225         __le16 fc;
1226         unsigned int frag, seq;
1227         struct ieee80211_fragment_entry *entry;
1228         struct sk_buff *skb;
1229
1230         hdr = (struct ieee80211_hdr *)rx->skb->data;
1231         fc = hdr->frame_control;
1232         sc = le16_to_cpu(hdr->seq_ctrl);
1233         frag = sc & IEEE80211_SCTL_FRAG;
1234
1235         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1236                    (rx->skb)->len < 24 ||
1237                    is_multicast_ether_addr(hdr->addr1))) {
1238                 /* not fragmented */
1239                 goto out;
1240         }
1241         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1242
1243         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1244
1245         if (frag == 0) {
1246                 /* This is the first fragment of a new frame. */
1247                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1248                                                  rx->queue, &(rx->skb));
1249                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1250                     ieee80211_has_protected(fc)) {
1251                         /* Store CCMP PN so that we can verify that the next
1252                          * fragment has a sequential PN value. */
1253                         entry->ccmp = 1;
1254                         memcpy(entry->last_pn,
1255                                rx->key->u.ccmp.rx_pn[rx->queue],
1256                                CCMP_PN_LEN);
1257                 }
1258                 return RX_QUEUED;
1259         }
1260
1261         /* This is a fragment for a frame that should already be pending in
1262          * fragment cache. Add this fragment to the end of the pending entry.
1263          */
1264         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1265         if (!entry) {
1266                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1267                 return RX_DROP_MONITOR;
1268         }
1269
1270         /* Verify that MPDUs within one MSDU have sequential PN values.
1271          * (IEEE 802.11i, 8.3.3.4.5) */
1272         if (entry->ccmp) {
1273                 int i;
1274                 u8 pn[CCMP_PN_LEN], *rpn;
1275                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1276                         return RX_DROP_UNUSABLE;
1277                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1278                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1279                         pn[i]++;
1280                         if (pn[i])
1281                                 break;
1282                 }
1283                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1284                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1285                         return RX_DROP_UNUSABLE;
1286                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1287         }
1288
1289         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1290         __skb_queue_tail(&entry->skb_list, rx->skb);
1291         entry->last_frag = frag;
1292         entry->extra_len += rx->skb->len;
1293         if (ieee80211_has_morefrags(fc)) {
1294                 rx->skb = NULL;
1295                 return RX_QUEUED;
1296         }
1297
1298         rx->skb = __skb_dequeue(&entry->skb_list);
1299         if (skb_tailroom(rx->skb) < entry->extra_len) {
1300                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1301                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1302                                               GFP_ATOMIC))) {
1303                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1304                         __skb_queue_purge(&entry->skb_list);
1305                         return RX_DROP_UNUSABLE;
1306                 }
1307         }
1308         while ((skb = __skb_dequeue(&entry->skb_list))) {
1309                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1310                 dev_kfree_skb(skb);
1311         }
1312
1313         /* Complete frame has been reassembled - process it now */
1314         rx->flags |= IEEE80211_RX_FRAGMENTED;
1315
1316  out:
1317         if (rx->sta)
1318                 rx->sta->rx_packets++;
1319         if (is_multicast_ether_addr(hdr->addr1))
1320                 rx->local->dot11MulticastReceivedFrameCount++;
1321         else
1322                 ieee80211_led_rx(rx->local);
1323         return RX_CONTINUE;
1324 }
1325
1326 static ieee80211_rx_result debug_noinline
1327 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1328 {
1329         struct ieee80211_sub_if_data *sdata = rx->sdata;
1330         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1331
1332         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1333                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1334                 return RX_CONTINUE;
1335
1336         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1337             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1338                 return RX_DROP_UNUSABLE;
1339
1340         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1341                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1342         else
1343                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1344
1345         /* Free PS Poll skb here instead of returning RX_DROP that would
1346          * count as an dropped frame. */
1347         dev_kfree_skb(rx->skb);
1348
1349         return RX_QUEUED;
1350 }
1351
1352 static ieee80211_rx_result debug_noinline
1353 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1354 {
1355         u8 *data = rx->skb->data;
1356         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1357
1358         if (!ieee80211_is_data_qos(hdr->frame_control))
1359                 return RX_CONTINUE;
1360
1361         /* remove the qos control field, update frame type and meta-data */
1362         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1363                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1364         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1365         /* change frame type to non QOS */
1366         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1367
1368         return RX_CONTINUE;
1369 }
1370
1371 static int
1372 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1373 {
1374         if (unlikely(!rx->sta ||
1375             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1376                 return -EACCES;
1377
1378         return 0;
1379 }
1380
1381 static int
1382 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1383 {
1384         struct sk_buff *skb = rx->skb;
1385         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1386
1387         /*
1388          * Pass through unencrypted frames if the hardware has
1389          * decrypted them already.
1390          */
1391         if (status->flag & RX_FLAG_DECRYPTED)
1392                 return 0;
1393
1394         /* Drop unencrypted frames if key is set. */
1395         if (unlikely(!ieee80211_has_protected(fc) &&
1396                      !ieee80211_is_nullfunc(fc) &&
1397                      ieee80211_is_data(fc) &&
1398                      (rx->key || rx->sdata->drop_unencrypted)))
1399                 return -EACCES;
1400
1401         return 0;
1402 }
1403
1404 static int
1405 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1406 {
1407         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1408         __le16 fc = hdr->frame_control;
1409         int res;
1410
1411         res = ieee80211_drop_unencrypted(rx, fc);
1412         if (unlikely(res))
1413                 return res;
1414
1415         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1416                 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1417                              rx->key))
1418                         return -EACCES;
1419                 /* BIP does not use Protected field, so need to check MMIE */
1420                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1421                              ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1422                              rx->key))
1423                         return -EACCES;
1424                 /*
1425                  * When using MFP, Action frames are not allowed prior to
1426                  * having configured keys.
1427                  */
1428                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1429                              ieee80211_is_robust_mgmt_frame(
1430                                      (struct ieee80211_hdr *) rx->skb->data)))
1431                         return -EACCES;
1432         }
1433
1434         return 0;
1435 }
1436
1437 static int
1438 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1439 {
1440         struct ieee80211_sub_if_data *sdata = rx->sdata;
1441         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1442
1443         if (ieee80211_has_a4(hdr->frame_control) &&
1444             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1445                 return -1;
1446
1447         if (is_multicast_ether_addr(hdr->addr1) &&
1448             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1449              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1450                 return -1;
1451
1452         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1453 }
1454
1455 /*
1456  * requires that rx->skb is a frame with ethernet header
1457  */
1458 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1459 {
1460         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1461                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1462         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1463
1464         /*
1465          * Allow EAPOL frames to us/the PAE group address regardless
1466          * of whether the frame was encrypted or not.
1467          */
1468         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1469             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1470              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1471                 return true;
1472
1473         if (ieee80211_802_1x_port_control(rx) ||
1474             ieee80211_drop_unencrypted(rx, fc))
1475                 return false;
1476
1477         return true;
1478 }
1479
1480 /*
1481  * requires that rx->skb is a frame with ethernet header
1482  */
1483 static void
1484 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1485 {
1486         struct ieee80211_sub_if_data *sdata = rx->sdata;
1487         struct net_device *dev = sdata->dev;
1488         struct sk_buff *skb, *xmit_skb;
1489         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1490         struct sta_info *dsta;
1491
1492         skb = rx->skb;
1493         xmit_skb = NULL;
1494
1495         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1496              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1497             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1498             (rx->flags & IEEE80211_RX_RA_MATCH) &&
1499             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1500                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1501                         /*
1502                          * send multicast frames both to higher layers in
1503                          * local net stack and back to the wireless medium
1504                          */
1505                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1506                         if (!xmit_skb && net_ratelimit())
1507                                 printk(KERN_DEBUG "%s: failed to clone "
1508                                        "multicast frame\n", dev->name);
1509                 } else {
1510                         dsta = sta_info_get(sdata, skb->data);
1511                         if (dsta) {
1512                                 /*
1513                                  * The destination station is associated to
1514                                  * this AP (in this VLAN), so send the frame
1515                                  * directly to it and do not pass it to local
1516                                  * net stack.
1517                                  */
1518                                 xmit_skb = skb;
1519                                 skb = NULL;
1520                         }
1521                 }
1522         }
1523
1524         if (skb) {
1525                 int align __maybe_unused;
1526
1527 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1528                 /*
1529                  * 'align' will only take the values 0 or 2 here
1530                  * since all frames are required to be aligned
1531                  * to 2-byte boundaries when being passed to
1532                  * mac80211. That also explains the __skb_push()
1533                  * below.
1534                  */
1535                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1536                 if (align) {
1537                         if (WARN_ON(skb_headroom(skb) < 3)) {
1538                                 dev_kfree_skb(skb);
1539                                 skb = NULL;
1540                         } else {
1541                                 u8 *data = skb->data;
1542                                 size_t len = skb_headlen(skb);
1543                                 skb->data -= align;
1544                                 memmove(skb->data, data, len);
1545                                 skb_set_tail_pointer(skb, len);
1546                         }
1547                 }
1548 #endif
1549
1550                 if (skb) {
1551                         /* deliver to local stack */
1552                         skb->protocol = eth_type_trans(skb, dev);
1553                         memset(skb->cb, 0, sizeof(skb->cb));
1554                         netif_rx(skb);
1555                 }
1556         }
1557
1558         if (xmit_skb) {
1559                 /* send to wireless media */
1560                 xmit_skb->protocol = htons(ETH_P_802_3);
1561                 skb_reset_network_header(xmit_skb);
1562                 skb_reset_mac_header(xmit_skb);
1563                 dev_queue_xmit(xmit_skb);
1564         }
1565 }
1566
1567 static ieee80211_rx_result debug_noinline
1568 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1569 {
1570         struct net_device *dev = rx->sdata->dev;
1571         struct sk_buff *skb = rx->skb;
1572         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1573         __le16 fc = hdr->frame_control;
1574         struct sk_buff_head frame_list;
1575
1576         if (unlikely(!ieee80211_is_data(fc)))
1577                 return RX_CONTINUE;
1578
1579         if (unlikely(!ieee80211_is_data_present(fc)))
1580                 return RX_DROP_MONITOR;
1581
1582         if (!(rx->flags & IEEE80211_RX_AMSDU))
1583                 return RX_CONTINUE;
1584
1585         if (ieee80211_has_a4(hdr->frame_control) &&
1586             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1587             !rx->sdata->u.vlan.sta)
1588                 return RX_DROP_UNUSABLE;
1589
1590         if (is_multicast_ether_addr(hdr->addr1) &&
1591             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1592               rx->sdata->u.vlan.sta) ||
1593              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1594               rx->sdata->u.mgd.use_4addr)))
1595                 return RX_DROP_UNUSABLE;
1596
1597         skb->dev = dev;
1598         __skb_queue_head_init(&frame_list);
1599
1600         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1601                                  rx->sdata->vif.type,
1602                                  rx->local->hw.extra_tx_headroom);
1603
1604         while (!skb_queue_empty(&frame_list)) {
1605                 rx->skb = __skb_dequeue(&frame_list);
1606
1607                 if (!ieee80211_frame_allowed(rx, fc)) {
1608                         dev_kfree_skb(rx->skb);
1609                         continue;
1610                 }
1611                 dev->stats.rx_packets++;
1612                 dev->stats.rx_bytes += rx->skb->len;
1613
1614                 ieee80211_deliver_skb(rx);
1615         }
1616
1617         return RX_QUEUED;
1618 }
1619
1620 #ifdef CONFIG_MAC80211_MESH
1621 static ieee80211_rx_result
1622 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1623 {
1624         struct ieee80211_hdr *hdr;
1625         struct ieee80211s_hdr *mesh_hdr;
1626         unsigned int hdrlen;
1627         struct sk_buff *skb = rx->skb, *fwd_skb;
1628         struct ieee80211_local *local = rx->local;
1629         struct ieee80211_sub_if_data *sdata = rx->sdata;
1630
1631         hdr = (struct ieee80211_hdr *) skb->data;
1632         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1633         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1634
1635         if (!ieee80211_is_data(hdr->frame_control))
1636                 return RX_CONTINUE;
1637
1638         if (!mesh_hdr->ttl)
1639                 /* illegal frame */
1640                 return RX_DROP_MONITOR;
1641
1642         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1643                 struct mesh_path *mppath;
1644                 char *proxied_addr;
1645                 char *mpp_addr;
1646
1647                 if (is_multicast_ether_addr(hdr->addr1)) {
1648                         mpp_addr = hdr->addr3;
1649                         proxied_addr = mesh_hdr->eaddr1;
1650                 } else {
1651                         mpp_addr = hdr->addr4;
1652                         proxied_addr = mesh_hdr->eaddr2;
1653                 }
1654
1655                 rcu_read_lock();
1656                 mppath = mpp_path_lookup(proxied_addr, sdata);
1657                 if (!mppath) {
1658                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1659                 } else {
1660                         spin_lock_bh(&mppath->state_lock);
1661                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1662                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1663                         spin_unlock_bh(&mppath->state_lock);
1664                 }
1665                 rcu_read_unlock();
1666         }
1667
1668         /* Frame has reached destination.  Don't forward */
1669         if (!is_multicast_ether_addr(hdr->addr1) &&
1670             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1671                 return RX_CONTINUE;
1672
1673         mesh_hdr->ttl--;
1674
1675         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1676                 if (!mesh_hdr->ttl)
1677                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1678                                                      dropped_frames_ttl);
1679                 else {
1680                         struct ieee80211_hdr *fwd_hdr;
1681                         struct ieee80211_tx_info *info;
1682
1683                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1684
1685                         if (!fwd_skb && net_ratelimit())
1686                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1687                                                    sdata->name);
1688
1689                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1690                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1691                         info = IEEE80211_SKB_CB(fwd_skb);
1692                         memset(info, 0, sizeof(*info));
1693                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1694                         info->control.vif = &rx->sdata->vif;
1695                         skb_set_queue_mapping(skb,
1696                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1697                         ieee80211_set_qos_hdr(local, skb);
1698                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1699                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1700                                                                 fwded_mcast);
1701                         else {
1702                                 int err;
1703                                 /*
1704                                  * Save TA to addr1 to send TA a path error if a
1705                                  * suitable next hop is not found
1706                                  */
1707                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1708                                                 ETH_ALEN);
1709                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1710                                 /* Failed to immediately resolve next hop:
1711                                  * fwded frame was dropped or will be added
1712                                  * later to the pending skb queue.  */
1713                                 if (err)
1714                                         return RX_DROP_MONITOR;
1715
1716                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1717                                                                 fwded_unicast);
1718                         }
1719                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1720                                                      fwded_frames);
1721                         ieee80211_add_pending_skb(local, fwd_skb);
1722                 }
1723         }
1724
1725         if (is_multicast_ether_addr(hdr->addr1) ||
1726             sdata->dev->flags & IFF_PROMISC)
1727                 return RX_CONTINUE;
1728         else
1729                 return RX_DROP_MONITOR;
1730 }
1731 #endif
1732
1733 static ieee80211_rx_result debug_noinline
1734 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1735 {
1736         struct ieee80211_sub_if_data *sdata = rx->sdata;
1737         struct ieee80211_local *local = rx->local;
1738         struct net_device *dev = sdata->dev;
1739         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1740         __le16 fc = hdr->frame_control;
1741         int err;
1742
1743         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1744                 return RX_CONTINUE;
1745
1746         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1747                 return RX_DROP_MONITOR;
1748
1749         /*
1750          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1751          * that a 4-addr station can be detected and moved into a separate VLAN
1752          */
1753         if (ieee80211_has_a4(hdr->frame_control) &&
1754             sdata->vif.type == NL80211_IFTYPE_AP)
1755                 return RX_DROP_MONITOR;
1756
1757         err = __ieee80211_data_to_8023(rx);
1758         if (unlikely(err))
1759                 return RX_DROP_UNUSABLE;
1760
1761         if (!ieee80211_frame_allowed(rx, fc))
1762                 return RX_DROP_MONITOR;
1763
1764         rx->skb->dev = dev;
1765
1766         dev->stats.rx_packets++;
1767         dev->stats.rx_bytes += rx->skb->len;
1768
1769         if (ieee80211_is_data(hdr->frame_control) &&
1770             !is_multicast_ether_addr(hdr->addr1) &&
1771             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1772                         mod_timer(&local->dynamic_ps_timer, jiffies +
1773                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1774         }
1775
1776         ieee80211_deliver_skb(rx);
1777
1778         return RX_QUEUED;
1779 }
1780
1781 static ieee80211_rx_result debug_noinline
1782 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1783 {
1784         struct ieee80211_local *local = rx->local;
1785         struct ieee80211_hw *hw = &local->hw;
1786         struct sk_buff *skb = rx->skb;
1787         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1788         struct tid_ampdu_rx *tid_agg_rx;
1789         u16 start_seq_num;
1790         u16 tid;
1791
1792         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1793                 return RX_CONTINUE;
1794
1795         if (ieee80211_is_back_req(bar->frame_control)) {
1796                 if (!rx->sta)
1797                         return RX_DROP_MONITOR;
1798                 tid = le16_to_cpu(bar->control) >> 12;
1799                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1800                                         != HT_AGG_STATE_OPERATIONAL)
1801                         return RX_DROP_MONITOR;
1802                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1803
1804                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1805
1806                 /* reset session timer */
1807                 if (tid_agg_rx->timeout)
1808                         mod_timer(&tid_agg_rx->session_timer,
1809                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1810
1811                 /* release stored frames up to start of BAR */
1812                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1813                                                  frames);
1814                 kfree_skb(skb);
1815                 return RX_QUEUED;
1816         }
1817
1818         return RX_CONTINUE;
1819 }
1820
1821 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1822                                            struct ieee80211_mgmt *mgmt,
1823                                            size_t len)
1824 {
1825         struct ieee80211_local *local = sdata->local;
1826         struct sk_buff *skb;
1827         struct ieee80211_mgmt *resp;
1828
1829         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1830                 /* Not to own unicast address */
1831                 return;
1832         }
1833
1834         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1835             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1836                 /* Not from the current AP or not associated yet. */
1837                 return;
1838         }
1839
1840         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1841                 /* Too short SA Query request frame */
1842                 return;
1843         }
1844
1845         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1846         if (skb == NULL)
1847                 return;
1848
1849         skb_reserve(skb, local->hw.extra_tx_headroom);
1850         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1851         memset(resp, 0, 24);
1852         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1853         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1854         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1855         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1856                                           IEEE80211_STYPE_ACTION);
1857         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1858         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1859         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1860         memcpy(resp->u.action.u.sa_query.trans_id,
1861                mgmt->u.action.u.sa_query.trans_id,
1862                WLAN_SA_QUERY_TR_ID_LEN);
1863
1864         ieee80211_tx_skb(sdata, skb);
1865 }
1866
1867 static ieee80211_rx_result debug_noinline
1868 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1869 {
1870         struct ieee80211_local *local = rx->local;
1871         struct ieee80211_sub_if_data *sdata = rx->sdata;
1872         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1873         struct sk_buff *nskb;
1874         struct ieee80211_rx_status *status;
1875         int len = rx->skb->len;
1876
1877         if (!ieee80211_is_action(mgmt->frame_control))
1878                 return RX_CONTINUE;
1879
1880         /* drop too small frames */
1881         if (len < IEEE80211_MIN_ACTION_SIZE)
1882                 return RX_DROP_UNUSABLE;
1883
1884         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
1885                 return RX_DROP_UNUSABLE;
1886
1887         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1888                 return RX_DROP_UNUSABLE;
1889
1890         if (ieee80211_drop_unencrypted_mgmt(rx))
1891                 return RX_DROP_UNUSABLE;
1892
1893         switch (mgmt->u.action.category) {
1894         case WLAN_CATEGORY_BACK:
1895                 /*
1896                  * The aggregation code is not prepared to handle
1897                  * anything but STA/AP due to the BSSID handling;
1898                  * IBSS could work in the code but isn't supported
1899                  * by drivers or the standard.
1900                  */
1901                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1902                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1903                     sdata->vif.type != NL80211_IFTYPE_AP)
1904                         break;
1905
1906                 /* verify action_code is present */
1907                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1908                         break;
1909
1910                 switch (mgmt->u.action.u.addba_req.action_code) {
1911                 case WLAN_ACTION_ADDBA_REQ:
1912                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1913                                    sizeof(mgmt->u.action.u.addba_req)))
1914                                 return RX_DROP_MONITOR;
1915                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1916                         goto handled;
1917                 case WLAN_ACTION_ADDBA_RESP:
1918                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1919                                    sizeof(mgmt->u.action.u.addba_resp)))
1920                                 break;
1921                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1922                         goto handled;
1923                 case WLAN_ACTION_DELBA:
1924                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1925                                    sizeof(mgmt->u.action.u.delba)))
1926                                 break;
1927                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1928                         goto handled;
1929                 }
1930                 break;
1931         case WLAN_CATEGORY_SPECTRUM_MGMT:
1932                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1933                         break;
1934
1935                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1936                         break;
1937
1938                 /* verify action_code is present */
1939                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1940                         break;
1941
1942                 switch (mgmt->u.action.u.measurement.action_code) {
1943                 case WLAN_ACTION_SPCT_MSR_REQ:
1944                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1945                                    sizeof(mgmt->u.action.u.measurement)))
1946                                 break;
1947                         ieee80211_process_measurement_req(sdata, mgmt, len);
1948                         goto handled;
1949                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1950                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1951                                    sizeof(mgmt->u.action.u.chan_switch)))
1952                                 break;
1953
1954                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1955                                 break;
1956
1957                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1958                                 break;
1959
1960                         return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1961                 }
1962                 break;
1963         case WLAN_CATEGORY_SA_QUERY:
1964                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1965                            sizeof(mgmt->u.action.u.sa_query)))
1966                         break;
1967
1968                 switch (mgmt->u.action.u.sa_query.action) {
1969                 case WLAN_ACTION_SA_QUERY_REQUEST:
1970                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1971                                 break;
1972                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1973                         goto handled;
1974                 }
1975                 break;
1976         }
1977
1978         /*
1979          * For AP mode, hostapd is responsible for handling any action
1980          * frames that we didn't handle, including returning unknown
1981          * ones. For all other modes we will return them to the sender,
1982          * setting the 0x80 bit in the action category, as required by
1983          * 802.11-2007 7.3.1.11.
1984          */
1985         if (sdata->vif.type == NL80211_IFTYPE_AP ||
1986             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1987                 return RX_DROP_MONITOR;
1988
1989         /*
1990          * Getting here means the kernel doesn't know how to handle
1991          * it, but maybe userspace does ... include returned frames
1992          * so userspace can register for those to know whether ones
1993          * it transmitted were processed or returned.
1994          */
1995         status = IEEE80211_SKB_RXCB(rx->skb);
1996
1997         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1998             cfg80211_rx_action(rx->sdata->dev, status->freq,
1999                                rx->skb->data, rx->skb->len,
2000                                GFP_ATOMIC))
2001                 goto handled;
2002
2003         /* do not return rejected action frames */
2004         if (mgmt->u.action.category & 0x80)
2005                 return RX_DROP_UNUSABLE;
2006
2007         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2008                                GFP_ATOMIC);
2009         if (nskb) {
2010                 struct ieee80211_mgmt *mgmt = (void *)nskb->data;
2011
2012                 mgmt->u.action.category |= 0x80;
2013                 memcpy(mgmt->da, mgmt->sa, ETH_ALEN);
2014                 memcpy(mgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2015
2016                 memset(nskb->cb, 0, sizeof(nskb->cb));
2017
2018                 ieee80211_tx_skb(rx->sdata, nskb);
2019         }
2020
2021  handled:
2022         if (rx->sta)
2023                 rx->sta->rx_packets++;
2024         dev_kfree_skb(rx->skb);
2025         return RX_QUEUED;
2026 }
2027
2028 static ieee80211_rx_result debug_noinline
2029 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2030 {
2031         struct ieee80211_sub_if_data *sdata = rx->sdata;
2032         ieee80211_rx_result rxs;
2033
2034         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
2035                 return RX_DROP_MONITOR;
2036
2037         if (ieee80211_drop_unencrypted_mgmt(rx))
2038                 return RX_DROP_UNUSABLE;
2039
2040         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2041         if (rxs != RX_CONTINUE)
2042                 return rxs;
2043
2044         if (ieee80211_vif_is_mesh(&sdata->vif))
2045                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
2046
2047         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
2048                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
2049
2050         if (sdata->vif.type == NL80211_IFTYPE_STATION)
2051                 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
2052
2053         return RX_DROP_MONITOR;
2054 }
2055
2056 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2057                                             struct ieee80211_rx_data *rx)
2058 {
2059         int keyidx;
2060         unsigned int hdrlen;
2061
2062         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2063         if (rx->skb->len >= hdrlen + 4)
2064                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2065         else
2066                 keyidx = -1;
2067
2068         if (!rx->sta) {
2069                 /*
2070                  * Some hardware seem to generate incorrect Michael MIC
2071                  * reports; ignore them to avoid triggering countermeasures.
2072                  */
2073                 return;
2074         }
2075
2076         if (!ieee80211_has_protected(hdr->frame_control))
2077                 return;
2078
2079         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2080                 /*
2081                  * APs with pairwise keys should never receive Michael MIC
2082                  * errors for non-zero keyidx because these are reserved for
2083                  * group keys and only the AP is sending real multicast
2084                  * frames in the BSS.
2085                  */
2086                 return;
2087         }
2088
2089         if (!ieee80211_is_data(hdr->frame_control) &&
2090             !ieee80211_is_auth(hdr->frame_control))
2091                 return;
2092
2093         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2094                                         GFP_ATOMIC);
2095 }
2096
2097 /* TODO: use IEEE80211_RX_FRAGMENTED */
2098 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2099                                         struct ieee80211_rate *rate)
2100 {
2101         struct ieee80211_sub_if_data *sdata;
2102         struct ieee80211_local *local = rx->local;
2103         struct ieee80211_rtap_hdr {
2104                 struct ieee80211_radiotap_header hdr;
2105                 u8 flags;
2106                 u8 rate_or_pad;
2107                 __le16 chan_freq;
2108                 __le16 chan_flags;
2109         } __attribute__ ((packed)) *rthdr;
2110         struct sk_buff *skb = rx->skb, *skb2;
2111         struct net_device *prev_dev = NULL;
2112         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2113
2114         if (status->flag & RX_FLAG_INTERNAL_CMTR)
2115                 goto out_free_skb;
2116
2117         if (skb_headroom(skb) < sizeof(*rthdr) &&
2118             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2119                 goto out_free_skb;
2120
2121         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2122         memset(rthdr, 0, sizeof(*rthdr));
2123         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2124         rthdr->hdr.it_present =
2125                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2126                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2127
2128         if (rate) {
2129                 rthdr->rate_or_pad = rate->bitrate / 5;
2130                 rthdr->hdr.it_present |=
2131                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2132         }
2133         rthdr->chan_freq = cpu_to_le16(status->freq);
2134
2135         if (status->band == IEEE80211_BAND_5GHZ)
2136                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2137                                                 IEEE80211_CHAN_5GHZ);
2138         else
2139                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2140                                                 IEEE80211_CHAN_2GHZ);
2141
2142         skb_set_mac_header(skb, 0);
2143         skb->ip_summed = CHECKSUM_UNNECESSARY;
2144         skb->pkt_type = PACKET_OTHERHOST;
2145         skb->protocol = htons(ETH_P_802_2);
2146
2147         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2148                 if (!ieee80211_sdata_running(sdata))
2149                         continue;
2150
2151                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2152                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2153                         continue;
2154
2155                 if (prev_dev) {
2156                         skb2 = skb_clone(skb, GFP_ATOMIC);
2157                         if (skb2) {
2158                                 skb2->dev = prev_dev;
2159                                 netif_rx(skb2);
2160                         }
2161                 }
2162
2163                 prev_dev = sdata->dev;
2164                 sdata->dev->stats.rx_packets++;
2165                 sdata->dev->stats.rx_bytes += skb->len;
2166         }
2167
2168         if (prev_dev) {
2169                 skb->dev = prev_dev;
2170                 netif_rx(skb);
2171                 skb = NULL;
2172         } else
2173                 goto out_free_skb;
2174
2175         status->flag |= RX_FLAG_INTERNAL_CMTR;
2176         return;
2177
2178  out_free_skb:
2179         dev_kfree_skb(skb);
2180 }
2181
2182
2183 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2184                                          struct ieee80211_rx_data *rx,
2185                                          struct sk_buff *skb,
2186                                          struct ieee80211_rate *rate)
2187 {
2188         struct sk_buff_head reorder_release;
2189         ieee80211_rx_result res = RX_DROP_MONITOR;
2190
2191         __skb_queue_head_init(&reorder_release);
2192
2193         rx->skb = skb;
2194         rx->sdata = sdata;
2195
2196 #define CALL_RXH(rxh)                   \
2197         do {                            \
2198                 res = rxh(rx);          \
2199                 if (res != RX_CONTINUE) \
2200                         goto rxh_next;  \
2201         } while (0);
2202
2203         /*
2204          * NB: the rxh_next label works even if we jump
2205          *     to it from here because then the list will
2206          *     be empty, which is a trivial check
2207          */
2208         CALL_RXH(ieee80211_rx_h_passive_scan)
2209         CALL_RXH(ieee80211_rx_h_check)
2210
2211         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2212
2213         while ((skb = __skb_dequeue(&reorder_release))) {
2214                 /*
2215                  * all the other fields are valid across frames
2216                  * that belong to an aMPDU since they are on the
2217                  * same TID from the same station
2218                  */
2219                 rx->skb = skb;
2220
2221                 CALL_RXH(ieee80211_rx_h_decrypt)
2222                 CALL_RXH(ieee80211_rx_h_check_more_data)
2223                 CALL_RXH(ieee80211_rx_h_sta_process)
2224                 CALL_RXH(ieee80211_rx_h_defragment)
2225                 CALL_RXH(ieee80211_rx_h_ps_poll)
2226                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2227                 /* must be after MMIC verify so header is counted in MPDU mic */
2228                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2229                 CALL_RXH(ieee80211_rx_h_amsdu)
2230 #ifdef CONFIG_MAC80211_MESH
2231                 if (ieee80211_vif_is_mesh(&sdata->vif))
2232                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2233 #endif
2234                 CALL_RXH(ieee80211_rx_h_data)
2235
2236                 /* special treatment -- needs the queue */
2237                 res = ieee80211_rx_h_ctrl(rx, &reorder_release);
2238                 if (res != RX_CONTINUE)
2239                         goto rxh_next;
2240
2241                 CALL_RXH(ieee80211_rx_h_action)
2242                 CALL_RXH(ieee80211_rx_h_mgmt)
2243
2244 #undef CALL_RXH
2245
2246  rxh_next:
2247                 switch (res) {
2248                 case RX_DROP_MONITOR:
2249                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2250                         if (rx->sta)
2251                                 rx->sta->rx_dropped++;
2252                         /* fall through */
2253                 case RX_CONTINUE:
2254                         ieee80211_rx_cooked_monitor(rx, rate);
2255                         break;
2256                 case RX_DROP_UNUSABLE:
2257                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2258                         if (rx->sta)
2259                                 rx->sta->rx_dropped++;
2260                         dev_kfree_skb(rx->skb);
2261                         break;
2262                 case RX_QUEUED:
2263                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2264                         break;
2265                 }
2266         }
2267 }
2268
2269 /* main receive path */
2270
2271 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2272                                 struct ieee80211_rx_data *rx,
2273                                 struct ieee80211_hdr *hdr)
2274 {
2275         struct sk_buff *skb = rx->skb;
2276         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2277         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2278         int multicast = is_multicast_ether_addr(hdr->addr1);
2279
2280         switch (sdata->vif.type) {
2281         case NL80211_IFTYPE_STATION:
2282                 if (!bssid && !sdata->u.mgd.use_4addr)
2283                         return 0;
2284                 if (!multicast &&
2285                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2286                         if (!(sdata->dev->flags & IFF_PROMISC))
2287                                 return 0;
2288                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2289                 }
2290                 break;
2291         case NL80211_IFTYPE_ADHOC:
2292                 if (!bssid)
2293                         return 0;
2294                 if (ieee80211_is_beacon(hdr->frame_control)) {
2295                         return 1;
2296                 }
2297                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2298                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2299                                 return 0;
2300                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2301                 } else if (!multicast &&
2302                            compare_ether_addr(sdata->vif.addr,
2303                                               hdr->addr1) != 0) {
2304                         if (!(sdata->dev->flags & IFF_PROMISC))
2305                                 return 0;
2306                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2307                 } else if (!rx->sta) {
2308                         int rate_idx;
2309                         if (status->flag & RX_FLAG_HT)
2310                                 rate_idx = 0; /* TODO: HT rates */
2311                         else
2312                                 rate_idx = status->rate_idx;
2313                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2314                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2315                 }
2316                 break;
2317         case NL80211_IFTYPE_MESH_POINT:
2318                 if (!multicast &&
2319                     compare_ether_addr(sdata->vif.addr,
2320                                        hdr->addr1) != 0) {
2321                         if (!(sdata->dev->flags & IFF_PROMISC))
2322                                 return 0;
2323
2324                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2325                 }
2326                 break;
2327         case NL80211_IFTYPE_AP_VLAN:
2328         case NL80211_IFTYPE_AP:
2329                 if (!bssid) {
2330                         if (compare_ether_addr(sdata->vif.addr,
2331                                                hdr->addr1))
2332                                 return 0;
2333                 } else if (!ieee80211_bssid_match(bssid,
2334                                         sdata->vif.addr)) {
2335                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2336                                 return 0;
2337                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2338                 }
2339                 break;
2340         case NL80211_IFTYPE_WDS:
2341                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2342                         return 0;
2343                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2344                         return 0;
2345                 break;
2346         case NL80211_IFTYPE_MONITOR:
2347         case NL80211_IFTYPE_UNSPECIFIED:
2348         case __NL80211_IFTYPE_AFTER_LAST:
2349                 /* should never get here */
2350                 WARN_ON(1);
2351                 break;
2352         }
2353
2354         return 1;
2355 }
2356
2357 /*
2358  * This is the actual Rx frames handler. as it blongs to Rx path it must
2359  * be called with rcu_read_lock protection.
2360  */
2361 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2362                                          struct sk_buff *skb,
2363                                          struct ieee80211_rate *rate)
2364 {
2365         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2366         struct ieee80211_local *local = hw_to_local(hw);
2367         struct ieee80211_sub_if_data *sdata;
2368         struct ieee80211_hdr *hdr;
2369         struct ieee80211_rx_data rx;
2370         int prepares;
2371         struct ieee80211_sub_if_data *prev = NULL;
2372         struct sk_buff *skb_new;
2373         struct sta_info *sta, *tmp;
2374         bool found_sta = false;
2375
2376         hdr = (struct ieee80211_hdr *)skb->data;
2377         memset(&rx, 0, sizeof(rx));
2378         rx.skb = skb;
2379         rx.local = local;
2380
2381         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2382                 local->dot11ReceivedFragmentCount++;
2383
2384         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2385                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2386                 rx.flags |= IEEE80211_RX_IN_SCAN;
2387
2388         ieee80211_parse_qos(&rx);
2389         ieee80211_verify_alignment(&rx);
2390
2391         if (ieee80211_is_data(hdr->frame_control)) {
2392                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2393                         rx.sta = sta;
2394                         found_sta = true;
2395                         rx.sdata = sta->sdata;
2396
2397                         rx.flags |= IEEE80211_RX_RA_MATCH;
2398                         prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2399                         if (prepares) {
2400                                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2401                                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2402                                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2403                                 } else
2404                                         prev = rx.sdata;
2405                         }
2406                 }
2407         }
2408         if (!found_sta) {
2409                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2410                         if (!ieee80211_sdata_running(sdata))
2411                                 continue;
2412
2413                         if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2414                             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2415                                 continue;
2416
2417                         /*
2418                          * frame is destined for this interface, but if it's
2419                          * not also for the previous one we handle that after
2420                          * the loop to avoid copying the SKB once too much
2421                          */
2422
2423                         if (!prev) {
2424                                 prev = sdata;
2425                                 continue;
2426                         }
2427
2428                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2429
2430                         rx.flags |= IEEE80211_RX_RA_MATCH;
2431                         prepares = prepare_for_handlers(prev, &rx, hdr);
2432
2433                         if (!prepares)
2434                                 goto next;
2435
2436                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2437                                 rx.sdata = prev;
2438                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2439                                         ieee80211_rx_michael_mic_report(hdr,
2440                                                                         &rx);
2441                                 goto next;
2442                         }
2443
2444                         /*
2445                          * frame was destined for the previous interface
2446                          * so invoke RX handlers for it
2447                          */
2448
2449                         skb_new = skb_copy(skb, GFP_ATOMIC);
2450                         if (!skb_new) {
2451                                 if (net_ratelimit())
2452                                         printk(KERN_DEBUG "%s: failed to copy "
2453                                                "multicast frame for %s\n",
2454                                                wiphy_name(local->hw.wiphy),
2455                                                prev->name);
2456                                 goto next;
2457                         }
2458                         ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
2459 next:
2460                         prev = sdata;
2461                 }
2462
2463                 if (prev) {
2464                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2465
2466                         rx.flags |= IEEE80211_RX_RA_MATCH;
2467                         prepares = prepare_for_handlers(prev, &rx, hdr);
2468
2469                         if (!prepares)
2470                                 prev = NULL;
2471                 }
2472         }
2473         if (prev)
2474                 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate);
2475         else
2476                 dev_kfree_skb(skb);
2477 }
2478
2479 /*
2480  * This is the receive path handler. It is called by a low level driver when an
2481  * 802.11 MPDU is received from the hardware.
2482  */
2483 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2484 {
2485         struct ieee80211_local *local = hw_to_local(hw);
2486         struct ieee80211_rate *rate = NULL;
2487         struct ieee80211_supported_band *sband;
2488         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2489
2490         WARN_ON_ONCE(softirq_count() == 0);
2491
2492         if (WARN_ON(status->band < 0 ||
2493                     status->band >= IEEE80211_NUM_BANDS))
2494                 goto drop;
2495
2496         sband = local->hw.wiphy->bands[status->band];
2497         if (WARN_ON(!sband))
2498                 goto drop;
2499
2500         /*
2501          * If we're suspending, it is possible although not too likely
2502          * that we'd be receiving frames after having already partially
2503          * quiesced the stack. We can't process such frames then since
2504          * that might, for example, cause stations to be added or other
2505          * driver callbacks be invoked.
2506          */
2507         if (unlikely(local->quiescing || local->suspended))
2508                 goto drop;
2509
2510         /*
2511          * The same happens when we're not even started,
2512          * but that's worth a warning.
2513          */
2514         if (WARN_ON(!local->started))
2515                 goto drop;
2516
2517         if (status->flag & RX_FLAG_HT) {
2518                 /*
2519                  * rate_idx is MCS index, which can be [0-76] as documented on:
2520                  *
2521                  * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2522                  *
2523                  * Anything else would be some sort of driver or hardware error.
2524                  * The driver should catch hardware errors.
2525                  */
2526                 if (WARN((status->rate_idx < 0 ||
2527                          status->rate_idx > 76),
2528                          "Rate marked as an HT rate but passed "
2529                          "status->rate_idx is not "
2530                          "an MCS index [0-76]: %d (0x%02x)\n",
2531                          status->rate_idx,
2532                          status->rate_idx))
2533                         goto drop;
2534         } else {
2535                 if (WARN_ON(status->rate_idx < 0 ||
2536                             status->rate_idx >= sband->n_bitrates))
2537                         goto drop;
2538                 rate = &sband->bitrates[status->rate_idx];
2539         }
2540
2541         /*
2542          * key references and virtual interfaces are protected using RCU
2543          * and this requires that we are in a read-side RCU section during
2544          * receive processing
2545          */
2546         rcu_read_lock();
2547
2548         /*
2549          * Frames with failed FCS/PLCP checksum are not returned,
2550          * all other frames are returned without radiotap header
2551          * if it was previously present.
2552          * Also, frames with less than 16 bytes are dropped.
2553          */
2554         skb = ieee80211_rx_monitor(local, skb, rate);
2555         if (!skb) {
2556                 rcu_read_unlock();
2557                 return;
2558         }
2559
2560         __ieee80211_rx_handle_packet(hw, skb, rate);
2561
2562         rcu_read_unlock();
2563
2564         return;
2565  drop:
2566         kfree_skb(skb);
2567 }
2568 EXPORT_SYMBOL(ieee80211_rx);
2569
2570 /* This is a version of the rx handler that can be called from hard irq
2571  * context. Post the skb on the queue and schedule the tasklet */
2572 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2573 {
2574         struct ieee80211_local *local = hw_to_local(hw);
2575
2576         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2577
2578         skb->pkt_type = IEEE80211_RX_MSG;
2579         skb_queue_tail(&local->skb_queue, skb);
2580         tasklet_schedule(&local->tasklet);
2581 }
2582 EXPORT_SYMBOL(ieee80211_rx_irqsafe);