Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-2.6.git] / net / mac80211 / rx.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <net/mac80211.h>
20 #include <net/ieee80211_radiotap.h>
21
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "led.h"
25 #include "mesh.h"
26 #include "wep.h"
27 #include "wpa.h"
28 #include "tkip.h"
29 #include "wme.h"
30
31 /*
32  * monitor mode reception
33  *
34  * This function cleans up the SKB, i.e. it removes all the stuff
35  * only useful for monitoring.
36  */
37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
38                                            struct sk_buff *skb)
39 {
40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
41                 if (likely(skb->len > FCS_LEN))
42                         __pskb_trim(skb, skb->len - FCS_LEN);
43                 else {
44                         /* driver bug */
45                         WARN_ON(1);
46                         dev_kfree_skb(skb);
47                         skb = NULL;
48                 }
49         }
50
51         return skb;
52 }
53
54 static inline int should_drop_frame(struct sk_buff *skb,
55                                     int present_fcs_len)
56 {
57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
59
60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
61                 return 1;
62         if (unlikely(skb->len < 16 + present_fcs_len))
63                 return 1;
64         if (ieee80211_is_ctl(hdr->frame_control) &&
65             !ieee80211_is_pspoll(hdr->frame_control) &&
66             !ieee80211_is_back_req(hdr->frame_control))
67                 return 1;
68         return 0;
69 }
70
71 static int
72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
73                           struct ieee80211_rx_status *status)
74 {
75         int len;
76
77         /* always present fields */
78         len = sizeof(struct ieee80211_radiotap_header) + 9;
79
80         if (status->flag & RX_FLAG_TSFT)
81                 len += 8;
82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
83                 len += 1;
84
85         if (len & 1) /* padding for RX_FLAGS if necessary */
86                 len++;
87
88         return len;
89 }
90
91 /*
92  * ieee80211_add_rx_radiotap_header - add radiotap header
93  *
94  * add a radiotap header containing all the fields which the hardware provided.
95  */
96 static void
97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
98                                  struct sk_buff *skb,
99                                  struct ieee80211_rate *rate,
100                                  int rtap_len)
101 {
102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
103         struct ieee80211_radiotap_header *rthdr;
104         unsigned char *pos;
105         u16 rx_flags = 0;
106
107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
108         memset(rthdr, 0, rtap_len);
109
110         /* radiotap header, set always present flags */
111         rthdr->it_present =
112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
116         rthdr->it_len = cpu_to_le16(rtap_len);
117
118         pos = (unsigned char *)(rthdr+1);
119
120         /* the order of the following fields is important */
121
122         /* IEEE80211_RADIOTAP_TSFT */
123         if (status->flag & RX_FLAG_TSFT) {
124                 put_unaligned_le64(status->mactime, pos);
125                 rthdr->it_present |=
126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
127                 pos += 8;
128         }
129
130         /* IEEE80211_RADIOTAP_FLAGS */
131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
135         if (status->flag & RX_FLAG_SHORTPRE)
136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
137         pos++;
138
139         /* IEEE80211_RADIOTAP_RATE */
140         if (status->flag & RX_FLAG_HT) {
141                 /*
142                  * TODO: add following information into radiotap header once
143                  * suitable fields are defined for it:
144                  * - MCS index (status->rate_idx)
145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
147                  */
148                 *pos = 0;
149         } else {
150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
151                 *pos = rate->bitrate / 5;
152         }
153         pos++;
154
155         /* IEEE80211_RADIOTAP_CHANNEL */
156         put_unaligned_le16(status->freq, pos);
157         pos += 2;
158         if (status->band == IEEE80211_BAND_5GHZ)
159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
160                                    pos);
161         else if (status->flag & RX_FLAG_HT)
162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
163                                    pos);
164         else if (rate->flags & IEEE80211_RATE_ERP_G)
165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
166                                    pos);
167         else
168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
169                                    pos);
170         pos += 2;
171
172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
174                 *pos = status->signal;
175                 rthdr->it_present |=
176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
177                 pos++;
178         }
179
180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
181
182         /* IEEE80211_RADIOTAP_ANTENNA */
183         *pos = status->antenna;
184         pos++;
185
186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
187
188         /* IEEE80211_RADIOTAP_RX_FLAGS */
189         /* ensure 2 byte alignment for the 2 byte field as required */
190         if ((pos - (u8 *)rthdr) & 1)
191                 pos++;
192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
194         put_unaligned_le16(rx_flags, pos);
195         pos += 2;
196 }
197
198 /*
199  * This function copies a received frame to all monitor interfaces and
200  * returns a cleaned-up SKB that no longer includes the FCS nor the
201  * radiotap header the driver might have added.
202  */
203 static struct sk_buff *
204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
205                      struct ieee80211_rate *rate)
206 {
207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
208         struct ieee80211_sub_if_data *sdata;
209         int needed_headroom = 0;
210         struct sk_buff *skb, *skb2;
211         struct net_device *prev_dev = NULL;
212         int present_fcs_len = 0;
213
214         /*
215          * First, we may need to make a copy of the skb because
216          *  (1) we need to modify it for radiotap (if not present), and
217          *  (2) the other RX handlers will modify the skb we got.
218          *
219          * We don't need to, of course, if we aren't going to return
220          * the SKB because it has a bad FCS/PLCP checksum.
221          */
222
223         /* room for the radiotap header based on driver features */
224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
225
226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
227                 present_fcs_len = FCS_LEN;
228
229         /* make sure hdr->frame_control is on the linear part */
230         if (!pskb_may_pull(origskb, 2)) {
231                 dev_kfree_skb(origskb);
232                 return NULL;
233         }
234
235         if (!local->monitors) {
236                 if (should_drop_frame(origskb, present_fcs_len)) {
237                         dev_kfree_skb(origskb);
238                         return NULL;
239                 }
240
241                 return remove_monitor_info(local, origskb);
242         }
243
244         if (should_drop_frame(origskb, present_fcs_len)) {
245                 /* only need to expand headroom if necessary */
246                 skb = origskb;
247                 origskb = NULL;
248
249                 /*
250                  * This shouldn't trigger often because most devices have an
251                  * RX header they pull before we get here, and that should
252                  * be big enough for our radiotap information. We should
253                  * probably export the length to drivers so that we can have
254                  * them allocate enough headroom to start with.
255                  */
256                 if (skb_headroom(skb) < needed_headroom &&
257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
258                         dev_kfree_skb(skb);
259                         return NULL;
260                 }
261         } else {
262                 /*
263                  * Need to make a copy and possibly remove radiotap header
264                  * and FCS from the original.
265                  */
266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
267
268                 origskb = remove_monitor_info(local, origskb);
269
270                 if (!skb)
271                         return origskb;
272         }
273
274         /* prepend radiotap information */
275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
276
277         skb_reset_mac_header(skb);
278         skb->ip_summed = CHECKSUM_UNNECESSARY;
279         skb->pkt_type = PACKET_OTHERHOST;
280         skb->protocol = htons(ETH_P_802_2);
281
282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
284                         continue;
285
286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
287                         continue;
288
289                 if (!ieee80211_sdata_running(sdata))
290                         continue;
291
292                 if (prev_dev) {
293                         skb2 = skb_clone(skb, GFP_ATOMIC);
294                         if (skb2) {
295                                 skb2->dev = prev_dev;
296                                 netif_receive_skb(skb2);
297                         }
298                 }
299
300                 prev_dev = sdata->dev;
301                 sdata->dev->stats.rx_packets++;
302                 sdata->dev->stats.rx_bytes += skb->len;
303         }
304
305         if (prev_dev) {
306                 skb->dev = prev_dev;
307                 netif_receive_skb(skb);
308         } else
309                 dev_kfree_skb(skb);
310
311         return origskb;
312 }
313
314
315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
316 {
317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
318         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
319         int tid;
320
321         /* does the frame have a qos control field? */
322         if (ieee80211_is_data_qos(hdr->frame_control)) {
323                 u8 *qc = ieee80211_get_qos_ctl(hdr);
324                 /* frame has qos control */
325                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
326                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
327                         status->rx_flags |= IEEE80211_RX_AMSDU;
328         } else {
329                 /*
330                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
331                  *
332                  *      Sequence numbers for management frames, QoS data
333                  *      frames with a broadcast/multicast address in the
334                  *      Address 1 field, and all non-QoS data frames sent
335                  *      by QoS STAs are assigned using an additional single
336                  *      modulo-4096 counter, [...]
337                  *
338                  * We also use that counter for non-QoS STAs.
339                  */
340                 tid = NUM_RX_DATA_QUEUES - 1;
341         }
342
343         rx->queue = tid;
344         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
345          * For now, set skb->priority to 0 for other cases. */
346         rx->skb->priority = (tid > 7) ? 0 : tid;
347 }
348
349 /**
350  * DOC: Packet alignment
351  *
352  * Drivers always need to pass packets that are aligned to two-byte boundaries
353  * to the stack.
354  *
355  * Additionally, should, if possible, align the payload data in a way that
356  * guarantees that the contained IP header is aligned to a four-byte
357  * boundary. In the case of regular frames, this simply means aligning the
358  * payload to a four-byte boundary (because either the IP header is directly
359  * contained, or IV/RFC1042 headers that have a length divisible by four are
360  * in front of it).  If the payload data is not properly aligned and the
361  * architecture doesn't support efficient unaligned operations, mac80211
362  * will align the data.
363  *
364  * With A-MSDU frames, however, the payload data address must yield two modulo
365  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
366  * push the IP header further back to a multiple of four again. Thankfully, the
367  * specs were sane enough this time around to require padding each A-MSDU
368  * subframe to a length that is a multiple of four.
369  *
370  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
371  * the payload is not supported, the driver is required to move the 802.11
372  * header to be directly in front of the payload in that case.
373  */
374 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
375 {
376 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
377         WARN_ONCE((unsigned long)rx->skb->data & 1,
378                   "unaligned packet at 0x%p\n", rx->skb->data);
379 #endif
380 }
381
382
383 /* rx handlers */
384
385 static ieee80211_rx_result debug_noinline
386 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
387 {
388         struct ieee80211_local *local = rx->local;
389         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
390         struct sk_buff *skb = rx->skb;
391
392         if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN)))
393                 return RX_CONTINUE;
394
395         if (test_bit(SCAN_HW_SCANNING, &local->scanning))
396                 return ieee80211_scan_rx(rx->sdata, skb);
397
398         if (test_bit(SCAN_SW_SCANNING, &local->scanning)) {
399                 /* drop all the other packets during a software scan anyway */
400                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
401                         dev_kfree_skb(skb);
402                 return RX_QUEUED;
403         }
404
405         /* scanning finished during invoking of handlers */
406         I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
407         return RX_DROP_UNUSABLE;
408 }
409
410
411 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
412 {
413         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
414
415         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
416                 return 0;
417
418         return ieee80211_is_robust_mgmt_frame(hdr);
419 }
420
421
422 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
423 {
424         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
425
426         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
427                 return 0;
428
429         return ieee80211_is_robust_mgmt_frame(hdr);
430 }
431
432
433 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
434 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
435 {
436         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
437         struct ieee80211_mmie *mmie;
438
439         if (skb->len < 24 + sizeof(*mmie) ||
440             !is_multicast_ether_addr(hdr->da))
441                 return -1;
442
443         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
444                 return -1; /* not a robust management frame */
445
446         mmie = (struct ieee80211_mmie *)
447                 (skb->data + skb->len - sizeof(*mmie));
448         if (mmie->element_id != WLAN_EID_MMIE ||
449             mmie->length != sizeof(*mmie) - 2)
450                 return -1;
451
452         return le16_to_cpu(mmie->key_id);
453 }
454
455
456 static ieee80211_rx_result
457 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
458 {
459         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
460         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
461         char *dev_addr = rx->sdata->vif.addr;
462
463         if (ieee80211_is_data(hdr->frame_control)) {
464                 if (is_multicast_ether_addr(hdr->addr1)) {
465                         if (ieee80211_has_tods(hdr->frame_control) ||
466                                 !ieee80211_has_fromds(hdr->frame_control))
467                                 return RX_DROP_MONITOR;
468                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
469                                 return RX_DROP_MONITOR;
470                 } else {
471                         if (!ieee80211_has_a4(hdr->frame_control))
472                                 return RX_DROP_MONITOR;
473                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
474                                 return RX_DROP_MONITOR;
475                 }
476         }
477
478         /* If there is not an established peer link and this is not a peer link
479          * establisment frame, beacon or probe, drop the frame.
480          */
481
482         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
483                 struct ieee80211_mgmt *mgmt;
484
485                 if (!ieee80211_is_mgmt(hdr->frame_control))
486                         return RX_DROP_MONITOR;
487
488                 if (ieee80211_is_action(hdr->frame_control)) {
489                         mgmt = (struct ieee80211_mgmt *)hdr;
490                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
491                                 return RX_DROP_MONITOR;
492                         return RX_CONTINUE;
493                 }
494
495                 if (ieee80211_is_probe_req(hdr->frame_control) ||
496                     ieee80211_is_probe_resp(hdr->frame_control) ||
497                     ieee80211_is_beacon(hdr->frame_control))
498                         return RX_CONTINUE;
499
500                 return RX_DROP_MONITOR;
501
502         }
503
504 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
505
506         if (ieee80211_is_data(hdr->frame_control) &&
507             is_multicast_ether_addr(hdr->addr1) &&
508             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
509                 return RX_DROP_MONITOR;
510 #undef msh_h_get
511
512         return RX_CONTINUE;
513 }
514
515 #define SEQ_MODULO 0x1000
516 #define SEQ_MASK   0xfff
517
518 static inline int seq_less(u16 sq1, u16 sq2)
519 {
520         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
521 }
522
523 static inline u16 seq_inc(u16 sq)
524 {
525         return (sq + 1) & SEQ_MASK;
526 }
527
528 static inline u16 seq_sub(u16 sq1, u16 sq2)
529 {
530         return (sq1 - sq2) & SEQ_MASK;
531 }
532
533
534 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
535                                             struct tid_ampdu_rx *tid_agg_rx,
536                                             int index)
537 {
538         struct ieee80211_local *local = hw_to_local(hw);
539         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
540         struct ieee80211_rx_status *status;
541
542         lockdep_assert_held(&tid_agg_rx->reorder_lock);
543
544         if (!skb)
545                 goto no_frame;
546
547         /* release the frame from the reorder ring buffer */
548         tid_agg_rx->stored_mpdu_num--;
549         tid_agg_rx->reorder_buf[index] = NULL;
550         status = IEEE80211_SKB_RXCB(skb);
551         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
552         skb_queue_tail(&local->rx_skb_queue, skb);
553
554 no_frame:
555         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
556 }
557
558 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
559                                              struct tid_ampdu_rx *tid_agg_rx,
560                                              u16 head_seq_num)
561 {
562         int index;
563
564         lockdep_assert_held(&tid_agg_rx->reorder_lock);
565
566         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
567                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
568                                                         tid_agg_rx->buf_size;
569                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
570         }
571 }
572
573 /*
574  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
575  * the skb was added to the buffer longer than this time ago, the earlier
576  * frames that have not yet been received are assumed to be lost and the skb
577  * can be released for processing. This may also release other skb's from the
578  * reorder buffer if there are no additional gaps between the frames.
579  *
580  * Callers must hold tid_agg_rx->reorder_lock.
581  */
582 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
583
584 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
585                                           struct tid_ampdu_rx *tid_agg_rx)
586 {
587         int index, j;
588
589         lockdep_assert_held(&tid_agg_rx->reorder_lock);
590
591         /* release the buffer until next missing frame */
592         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
593                                                 tid_agg_rx->buf_size;
594         if (!tid_agg_rx->reorder_buf[index] &&
595             tid_agg_rx->stored_mpdu_num > 1) {
596                 /*
597                  * No buffers ready to be released, but check whether any
598                  * frames in the reorder buffer have timed out.
599                  */
600                 int skipped = 1;
601                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
602                      j = (j + 1) % tid_agg_rx->buf_size) {
603                         if (!tid_agg_rx->reorder_buf[j]) {
604                                 skipped++;
605                                 continue;
606                         }
607                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
608                                         HT_RX_REORDER_BUF_TIMEOUT))
609                                 goto set_release_timer;
610
611 #ifdef CONFIG_MAC80211_HT_DEBUG
612                         if (net_ratelimit())
613                                 wiphy_debug(hw->wiphy,
614                                             "release an RX reorder frame due to timeout on earlier frames\n");
615 #endif
616                         ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
617
618                         /*
619                          * Increment the head seq# also for the skipped slots.
620                          */
621                         tid_agg_rx->head_seq_num =
622                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
623                         skipped = 0;
624                 }
625         } else while (tid_agg_rx->reorder_buf[index]) {
626                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
627                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
628                                                         tid_agg_rx->buf_size;
629         }
630
631         if (tid_agg_rx->stored_mpdu_num) {
632                 j = index = seq_sub(tid_agg_rx->head_seq_num,
633                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
634
635                 for (; j != (index - 1) % tid_agg_rx->buf_size;
636                      j = (j + 1) % tid_agg_rx->buf_size) {
637                         if (tid_agg_rx->reorder_buf[j])
638                                 break;
639                 }
640
641  set_release_timer:
642
643                 mod_timer(&tid_agg_rx->reorder_timer,
644                           tid_agg_rx->reorder_time[j] +
645                           HT_RX_REORDER_BUF_TIMEOUT);
646         } else {
647                 del_timer(&tid_agg_rx->reorder_timer);
648         }
649 }
650
651 /*
652  * As this function belongs to the RX path it must be under
653  * rcu_read_lock protection. It returns false if the frame
654  * can be processed immediately, true if it was consumed.
655  */
656 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
657                                              struct tid_ampdu_rx *tid_agg_rx,
658                                              struct sk_buff *skb)
659 {
660         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
661         u16 sc = le16_to_cpu(hdr->seq_ctrl);
662         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
663         u16 head_seq_num, buf_size;
664         int index;
665         bool ret = true;
666
667         spin_lock(&tid_agg_rx->reorder_lock);
668
669         buf_size = tid_agg_rx->buf_size;
670         head_seq_num = tid_agg_rx->head_seq_num;
671
672         /* frame with out of date sequence number */
673         if (seq_less(mpdu_seq_num, head_seq_num)) {
674                 dev_kfree_skb(skb);
675                 goto out;
676         }
677
678         /*
679          * If frame the sequence number exceeds our buffering window
680          * size release some previous frames to make room for this one.
681          */
682         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
683                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
684                 /* release stored frames up to new head to stack */
685                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
686         }
687
688         /* Now the new frame is always in the range of the reordering buffer */
689
690         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
691
692         /* check if we already stored this frame */
693         if (tid_agg_rx->reorder_buf[index]) {
694                 dev_kfree_skb(skb);
695                 goto out;
696         }
697
698         /*
699          * If the current MPDU is in the right order and nothing else
700          * is stored we can process it directly, no need to buffer it.
701          */
702         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
703             tid_agg_rx->stored_mpdu_num == 0) {
704                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
705                 ret = false;
706                 goto out;
707         }
708
709         /* put the frame in the reordering buffer */
710         tid_agg_rx->reorder_buf[index] = skb;
711         tid_agg_rx->reorder_time[index] = jiffies;
712         tid_agg_rx->stored_mpdu_num++;
713         ieee80211_sta_reorder_release(hw, tid_agg_rx);
714
715  out:
716         spin_unlock(&tid_agg_rx->reorder_lock);
717         return ret;
718 }
719
720 /*
721  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
722  * true if the MPDU was buffered, false if it should be processed.
723  */
724 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
725 {
726         struct sk_buff *skb = rx->skb;
727         struct ieee80211_local *local = rx->local;
728         struct ieee80211_hw *hw = &local->hw;
729         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
730         struct sta_info *sta = rx->sta;
731         struct tid_ampdu_rx *tid_agg_rx;
732         u16 sc;
733         int tid;
734
735         if (!ieee80211_is_data_qos(hdr->frame_control))
736                 goto dont_reorder;
737
738         /*
739          * filter the QoS data rx stream according to
740          * STA/TID and check if this STA/TID is on aggregation
741          */
742
743         if (!sta)
744                 goto dont_reorder;
745
746         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
747
748         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
749         if (!tid_agg_rx)
750                 goto dont_reorder;
751
752         /* qos null data frames are excluded */
753         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
754                 goto dont_reorder;
755
756         /* new, potentially un-ordered, ampdu frame - process it */
757
758         /* reset session timer */
759         if (tid_agg_rx->timeout)
760                 mod_timer(&tid_agg_rx->session_timer,
761                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
762
763         /* if this mpdu is fragmented - terminate rx aggregation session */
764         sc = le16_to_cpu(hdr->seq_ctrl);
765         if (sc & IEEE80211_SCTL_FRAG) {
766                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
767                 skb_queue_tail(&rx->sdata->skb_queue, skb);
768                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
769                 return;
770         }
771
772         /*
773          * No locking needed -- we will only ever process one
774          * RX packet at a time, and thus own tid_agg_rx. All
775          * other code manipulating it needs to (and does) make
776          * sure that we cannot get to it any more before doing
777          * anything with it.
778          */
779         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
780                 return;
781
782  dont_reorder:
783         skb_queue_tail(&local->rx_skb_queue, skb);
784 }
785
786 static ieee80211_rx_result debug_noinline
787 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
788 {
789         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
790         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
791
792         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
793         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
794                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
795                              rx->sta->last_seq_ctrl[rx->queue] ==
796                              hdr->seq_ctrl)) {
797                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
798                                 rx->local->dot11FrameDuplicateCount++;
799                                 rx->sta->num_duplicates++;
800                         }
801                         return RX_DROP_MONITOR;
802                 } else
803                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
804         }
805
806         if (unlikely(rx->skb->len < 16)) {
807                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
808                 return RX_DROP_MONITOR;
809         }
810
811         /* Drop disallowed frame classes based on STA auth/assoc state;
812          * IEEE 802.11, Chap 5.5.
813          *
814          * mac80211 filters only based on association state, i.e. it drops
815          * Class 3 frames from not associated stations. hostapd sends
816          * deauth/disassoc frames when needed. In addition, hostapd is
817          * responsible for filtering on both auth and assoc states.
818          */
819
820         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
821                 return ieee80211_rx_mesh_check(rx);
822
823         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
824                       ieee80211_is_pspoll(hdr->frame_control)) &&
825                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
826                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
827                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
828                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
829                      !ieee80211_has_tods(hdr->frame_control) &&
830                      ieee80211_is_data(hdr->frame_control)) ||
831                     !(status->rx_flags & IEEE80211_RX_RA_MATCH)) {
832                         /* Drop IBSS frames and frames for other hosts
833                          * silently. */
834                         return RX_DROP_MONITOR;
835                 }
836
837                 return RX_DROP_MONITOR;
838         }
839
840         return RX_CONTINUE;
841 }
842
843
844 static ieee80211_rx_result debug_noinline
845 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
846 {
847         struct sk_buff *skb = rx->skb;
848         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
849         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
850         int keyidx;
851         int hdrlen;
852         ieee80211_rx_result result = RX_DROP_UNUSABLE;
853         struct ieee80211_key *sta_ptk = NULL;
854         int mmie_keyidx = -1;
855         __le16 fc;
856
857         /*
858          * Key selection 101
859          *
860          * There are four types of keys:
861          *  - GTK (group keys)
862          *  - IGTK (group keys for management frames)
863          *  - PTK (pairwise keys)
864          *  - STK (station-to-station pairwise keys)
865          *
866          * When selecting a key, we have to distinguish between multicast
867          * (including broadcast) and unicast frames, the latter can only
868          * use PTKs and STKs while the former always use GTKs and IGTKs.
869          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
870          * unicast frames can also use key indices like GTKs. Hence, if we
871          * don't have a PTK/STK we check the key index for a WEP key.
872          *
873          * Note that in a regular BSS, multicast frames are sent by the
874          * AP only, associated stations unicast the frame to the AP first
875          * which then multicasts it on their behalf.
876          *
877          * There is also a slight problem in IBSS mode: GTKs are negotiated
878          * with each station, that is something we don't currently handle.
879          * The spec seems to expect that one negotiates the same key with
880          * every station but there's no such requirement; VLANs could be
881          * possible.
882          */
883
884         /*
885          * No point in finding a key and decrypting if the frame is neither
886          * addressed to us nor a multicast frame.
887          */
888         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
889                 return RX_CONTINUE;
890
891         /* start without a key */
892         rx->key = NULL;
893
894         if (rx->sta)
895                 sta_ptk = rcu_dereference(rx->sta->ptk);
896
897         fc = hdr->frame_control;
898
899         if (!ieee80211_has_protected(fc))
900                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
901
902         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
903                 rx->key = sta_ptk;
904                 if ((status->flag & RX_FLAG_DECRYPTED) &&
905                     (status->flag & RX_FLAG_IV_STRIPPED))
906                         return RX_CONTINUE;
907                 /* Skip decryption if the frame is not protected. */
908                 if (!ieee80211_has_protected(fc))
909                         return RX_CONTINUE;
910         } else if (mmie_keyidx >= 0) {
911                 /* Broadcast/multicast robust management frame / BIP */
912                 if ((status->flag & RX_FLAG_DECRYPTED) &&
913                     (status->flag & RX_FLAG_IV_STRIPPED))
914                         return RX_CONTINUE;
915
916                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
917                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
918                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
919                 if (rx->sta)
920                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
921                 if (!rx->key)
922                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
923         } else if (!ieee80211_has_protected(fc)) {
924                 /*
925                  * The frame was not protected, so skip decryption. However, we
926                  * need to set rx->key if there is a key that could have been
927                  * used so that the frame may be dropped if encryption would
928                  * have been expected.
929                  */
930                 struct ieee80211_key *key = NULL;
931                 struct ieee80211_sub_if_data *sdata = rx->sdata;
932                 int i;
933
934                 if (ieee80211_is_mgmt(fc) &&
935                     is_multicast_ether_addr(hdr->addr1) &&
936                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
937                         rx->key = key;
938                 else {
939                         if (rx->sta) {
940                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
941                                         key = rcu_dereference(rx->sta->gtk[i]);
942                                         if (key)
943                                                 break;
944                                 }
945                         }
946                         if (!key) {
947                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
948                                         key = rcu_dereference(sdata->keys[i]);
949                                         if (key)
950                                                 break;
951                                 }
952                         }
953                         if (key)
954                                 rx->key = key;
955                 }
956                 return RX_CONTINUE;
957         } else {
958                 u8 keyid;
959                 /*
960                  * The device doesn't give us the IV so we won't be
961                  * able to look up the key. That's ok though, we
962                  * don't need to decrypt the frame, we just won't
963                  * be able to keep statistics accurate.
964                  * Except for key threshold notifications, should
965                  * we somehow allow the driver to tell us which key
966                  * the hardware used if this flag is set?
967                  */
968                 if ((status->flag & RX_FLAG_DECRYPTED) &&
969                     (status->flag & RX_FLAG_IV_STRIPPED))
970                         return RX_CONTINUE;
971
972                 hdrlen = ieee80211_hdrlen(fc);
973
974                 if (rx->skb->len < 8 + hdrlen)
975                         return RX_DROP_UNUSABLE; /* TODO: count this? */
976
977                 /*
978                  * no need to call ieee80211_wep_get_keyidx,
979                  * it verifies a bunch of things we've done already
980                  */
981                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
982                 keyidx = keyid >> 6;
983
984                 /* check per-station GTK first, if multicast packet */
985                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
986                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
987
988                 /* if not found, try default key */
989                 if (!rx->key) {
990                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
991
992                         /*
993                          * RSNA-protected unicast frames should always be
994                          * sent with pairwise or station-to-station keys,
995                          * but for WEP we allow using a key index as well.
996                          */
997                         if (rx->key &&
998                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
999                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1000                             !is_multicast_ether_addr(hdr->addr1))
1001                                 rx->key = NULL;
1002                 }
1003         }
1004
1005         if (rx->key) {
1006                 rx->key->tx_rx_count++;
1007                 /* TODO: add threshold stuff again */
1008         } else {
1009                 return RX_DROP_MONITOR;
1010         }
1011
1012         if (skb_linearize(rx->skb))
1013                 return RX_DROP_UNUSABLE;
1014         /* the hdr variable is invalid now! */
1015
1016         switch (rx->key->conf.cipher) {
1017         case WLAN_CIPHER_SUITE_WEP40:
1018         case WLAN_CIPHER_SUITE_WEP104:
1019                 /* Check for weak IVs if possible */
1020                 if (rx->sta && ieee80211_is_data(fc) &&
1021                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
1022                      !(status->flag & RX_FLAG_DECRYPTED)) &&
1023                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1024                         rx->sta->wep_weak_iv_count++;
1025
1026                 result = ieee80211_crypto_wep_decrypt(rx);
1027                 break;
1028         case WLAN_CIPHER_SUITE_TKIP:
1029                 result = ieee80211_crypto_tkip_decrypt(rx);
1030                 break;
1031         case WLAN_CIPHER_SUITE_CCMP:
1032                 result = ieee80211_crypto_ccmp_decrypt(rx);
1033                 break;
1034         case WLAN_CIPHER_SUITE_AES_CMAC:
1035                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1036                 break;
1037         default:
1038                 /*
1039                  * We can reach here only with HW-only algorithms
1040                  * but why didn't it decrypt the frame?!
1041                  */
1042                 return RX_DROP_UNUSABLE;
1043         }
1044
1045         /* either the frame has been decrypted or will be dropped */
1046         status->flag |= RX_FLAG_DECRYPTED;
1047
1048         return result;
1049 }
1050
1051 static ieee80211_rx_result debug_noinline
1052 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1053 {
1054         struct ieee80211_local *local;
1055         struct ieee80211_hdr *hdr;
1056         struct sk_buff *skb;
1057
1058         local = rx->local;
1059         skb = rx->skb;
1060         hdr = (struct ieee80211_hdr *) skb->data;
1061
1062         if (!local->pspolling)
1063                 return RX_CONTINUE;
1064
1065         if (!ieee80211_has_fromds(hdr->frame_control))
1066                 /* this is not from AP */
1067                 return RX_CONTINUE;
1068
1069         if (!ieee80211_is_data(hdr->frame_control))
1070                 return RX_CONTINUE;
1071
1072         if (!ieee80211_has_moredata(hdr->frame_control)) {
1073                 /* AP has no more frames buffered for us */
1074                 local->pspolling = false;
1075                 return RX_CONTINUE;
1076         }
1077
1078         /* more data bit is set, let's request a new frame from the AP */
1079         ieee80211_send_pspoll(local, rx->sdata);
1080
1081         return RX_CONTINUE;
1082 }
1083
1084 static void ap_sta_ps_start(struct sta_info *sta)
1085 {
1086         struct ieee80211_sub_if_data *sdata = sta->sdata;
1087         struct ieee80211_local *local = sdata->local;
1088
1089         atomic_inc(&sdata->bss->num_sta_ps);
1090         set_sta_flags(sta, WLAN_STA_PS_STA);
1091         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1092 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1093         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1094                sdata->name, sta->sta.addr, sta->sta.aid);
1095 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1096 }
1097
1098 static void ap_sta_ps_end(struct sta_info *sta)
1099 {
1100         struct ieee80211_sub_if_data *sdata = sta->sdata;
1101
1102         atomic_dec(&sdata->bss->num_sta_ps);
1103
1104 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1105         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1106                sdata->name, sta->sta.addr, sta->sta.aid);
1107 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1108
1109         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1110 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1111                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1112                        sdata->name, sta->sta.addr, sta->sta.aid);
1113 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1114                 return;
1115         }
1116
1117         ieee80211_sta_ps_deliver_wakeup(sta);
1118 }
1119
1120 static ieee80211_rx_result debug_noinline
1121 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1122 {
1123         struct sta_info *sta = rx->sta;
1124         struct sk_buff *skb = rx->skb;
1125         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1126         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1127
1128         if (!sta)
1129                 return RX_CONTINUE;
1130
1131         /*
1132          * Update last_rx only for IBSS packets which are for the current
1133          * BSSID to avoid keeping the current IBSS network alive in cases
1134          * where other STAs start using different BSSID.
1135          */
1136         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1137                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1138                                                 NL80211_IFTYPE_ADHOC);
1139                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1140                         sta->last_rx = jiffies;
1141         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1142                 /*
1143                  * Mesh beacons will update last_rx when if they are found to
1144                  * match the current local configuration when processed.
1145                  */
1146                 sta->last_rx = jiffies;
1147         }
1148
1149         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1150                 return RX_CONTINUE;
1151
1152         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1153                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1154
1155         sta->rx_fragments++;
1156         sta->rx_bytes += rx->skb->len;
1157         sta->last_signal = status->signal;
1158         ewma_add(&sta->avg_signal, -status->signal);
1159
1160         /*
1161          * Change STA power saving mode only at the end of a frame
1162          * exchange sequence.
1163          */
1164         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1165             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1166             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1167              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1168                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1169                         /*
1170                          * Ignore doze->wake transitions that are
1171                          * indicated by non-data frames, the standard
1172                          * is unclear here, but for example going to
1173                          * PS mode and then scanning would cause a
1174                          * doze->wake transition for the probe request,
1175                          * and that is clearly undesirable.
1176                          */
1177                         if (ieee80211_is_data(hdr->frame_control) &&
1178                             !ieee80211_has_pm(hdr->frame_control))
1179                                 ap_sta_ps_end(sta);
1180                 } else {
1181                         if (ieee80211_has_pm(hdr->frame_control))
1182                                 ap_sta_ps_start(sta);
1183                 }
1184         }
1185
1186         /*
1187          * Drop (qos-)data::nullfunc frames silently, since they
1188          * are used only to control station power saving mode.
1189          */
1190         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1191             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1192                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1193
1194                 /*
1195                  * If we receive a 4-addr nullfunc frame from a STA
1196                  * that was not moved to a 4-addr STA vlan yet, drop
1197                  * the frame to the monitor interface, to make sure
1198                  * that hostapd sees it
1199                  */
1200                 if (ieee80211_has_a4(hdr->frame_control) &&
1201                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1202                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1203                       !rx->sdata->u.vlan.sta)))
1204                         return RX_DROP_MONITOR;
1205                 /*
1206                  * Update counter and free packet here to avoid
1207                  * counting this as a dropped packed.
1208                  */
1209                 sta->rx_packets++;
1210                 dev_kfree_skb(rx->skb);
1211                 return RX_QUEUED;
1212         }
1213
1214         return RX_CONTINUE;
1215 } /* ieee80211_rx_h_sta_process */
1216
1217 static inline struct ieee80211_fragment_entry *
1218 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1219                          unsigned int frag, unsigned int seq, int rx_queue,
1220                          struct sk_buff **skb)
1221 {
1222         struct ieee80211_fragment_entry *entry;
1223         int idx;
1224
1225         idx = sdata->fragment_next;
1226         entry = &sdata->fragments[sdata->fragment_next++];
1227         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1228                 sdata->fragment_next = 0;
1229
1230         if (!skb_queue_empty(&entry->skb_list)) {
1231 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1232                 struct ieee80211_hdr *hdr =
1233                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1234                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1235                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1236                        "addr1=%pM addr2=%pM\n",
1237                        sdata->name, idx,
1238                        jiffies - entry->first_frag_time, entry->seq,
1239                        entry->last_frag, hdr->addr1, hdr->addr2);
1240 #endif
1241                 __skb_queue_purge(&entry->skb_list);
1242         }
1243
1244         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1245         *skb = NULL;
1246         entry->first_frag_time = jiffies;
1247         entry->seq = seq;
1248         entry->rx_queue = rx_queue;
1249         entry->last_frag = frag;
1250         entry->ccmp = 0;
1251         entry->extra_len = 0;
1252
1253         return entry;
1254 }
1255
1256 static inline struct ieee80211_fragment_entry *
1257 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1258                           unsigned int frag, unsigned int seq,
1259                           int rx_queue, struct ieee80211_hdr *hdr)
1260 {
1261         struct ieee80211_fragment_entry *entry;
1262         int i, idx;
1263
1264         idx = sdata->fragment_next;
1265         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1266                 struct ieee80211_hdr *f_hdr;
1267
1268                 idx--;
1269                 if (idx < 0)
1270                         idx = IEEE80211_FRAGMENT_MAX - 1;
1271
1272                 entry = &sdata->fragments[idx];
1273                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1274                     entry->rx_queue != rx_queue ||
1275                     entry->last_frag + 1 != frag)
1276                         continue;
1277
1278                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1279
1280                 /*
1281                  * Check ftype and addresses are equal, else check next fragment
1282                  */
1283                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1284                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1285                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1286                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1287                         continue;
1288
1289                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1290                         __skb_queue_purge(&entry->skb_list);
1291                         continue;
1292                 }
1293                 return entry;
1294         }
1295
1296         return NULL;
1297 }
1298
1299 static ieee80211_rx_result debug_noinline
1300 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1301 {
1302         struct ieee80211_hdr *hdr;
1303         u16 sc;
1304         __le16 fc;
1305         unsigned int frag, seq;
1306         struct ieee80211_fragment_entry *entry;
1307         struct sk_buff *skb;
1308         struct ieee80211_rx_status *status;
1309
1310         hdr = (struct ieee80211_hdr *)rx->skb->data;
1311         fc = hdr->frame_control;
1312         sc = le16_to_cpu(hdr->seq_ctrl);
1313         frag = sc & IEEE80211_SCTL_FRAG;
1314
1315         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1316                    (rx->skb)->len < 24 ||
1317                    is_multicast_ether_addr(hdr->addr1))) {
1318                 /* not fragmented */
1319                 goto out;
1320         }
1321         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1322
1323         if (skb_linearize(rx->skb))
1324                 return RX_DROP_UNUSABLE;
1325
1326         /*
1327          *  skb_linearize() might change the skb->data and
1328          *  previously cached variables (in this case, hdr) need to
1329          *  be refreshed with the new data.
1330          */
1331         hdr = (struct ieee80211_hdr *)rx->skb->data;
1332         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1333
1334         if (frag == 0) {
1335                 /* This is the first fragment of a new frame. */
1336                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1337                                                  rx->queue, &(rx->skb));
1338                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1339                     ieee80211_has_protected(fc)) {
1340                         int queue = ieee80211_is_mgmt(fc) ?
1341                                 NUM_RX_DATA_QUEUES : rx->queue;
1342                         /* Store CCMP PN so that we can verify that the next
1343                          * fragment has a sequential PN value. */
1344                         entry->ccmp = 1;
1345                         memcpy(entry->last_pn,
1346                                rx->key->u.ccmp.rx_pn[queue],
1347                                CCMP_PN_LEN);
1348                 }
1349                 return RX_QUEUED;
1350         }
1351
1352         /* This is a fragment for a frame that should already be pending in
1353          * fragment cache. Add this fragment to the end of the pending entry.
1354          */
1355         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1356         if (!entry) {
1357                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1358                 return RX_DROP_MONITOR;
1359         }
1360
1361         /* Verify that MPDUs within one MSDU have sequential PN values.
1362          * (IEEE 802.11i, 8.3.3.4.5) */
1363         if (entry->ccmp) {
1364                 int i;
1365                 u8 pn[CCMP_PN_LEN], *rpn;
1366                 int queue;
1367                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1368                         return RX_DROP_UNUSABLE;
1369                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1370                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1371                         pn[i]++;
1372                         if (pn[i])
1373                                 break;
1374                 }
1375                 queue = ieee80211_is_mgmt(fc) ?
1376                         NUM_RX_DATA_QUEUES : rx->queue;
1377                 rpn = rx->key->u.ccmp.rx_pn[queue];
1378                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1379                         return RX_DROP_UNUSABLE;
1380                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1381         }
1382
1383         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1384         __skb_queue_tail(&entry->skb_list, rx->skb);
1385         entry->last_frag = frag;
1386         entry->extra_len += rx->skb->len;
1387         if (ieee80211_has_morefrags(fc)) {
1388                 rx->skb = NULL;
1389                 return RX_QUEUED;
1390         }
1391
1392         rx->skb = __skb_dequeue(&entry->skb_list);
1393         if (skb_tailroom(rx->skb) < entry->extra_len) {
1394                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1395                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1396                                               GFP_ATOMIC))) {
1397                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1398                         __skb_queue_purge(&entry->skb_list);
1399                         return RX_DROP_UNUSABLE;
1400                 }
1401         }
1402         while ((skb = __skb_dequeue(&entry->skb_list))) {
1403                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1404                 dev_kfree_skb(skb);
1405         }
1406
1407         /* Complete frame has been reassembled - process it now */
1408         status = IEEE80211_SKB_RXCB(rx->skb);
1409         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1410
1411  out:
1412         if (rx->sta)
1413                 rx->sta->rx_packets++;
1414         if (is_multicast_ether_addr(hdr->addr1))
1415                 rx->local->dot11MulticastReceivedFrameCount++;
1416         else
1417                 ieee80211_led_rx(rx->local);
1418         return RX_CONTINUE;
1419 }
1420
1421 static ieee80211_rx_result debug_noinline
1422 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1423 {
1424         struct ieee80211_sub_if_data *sdata = rx->sdata;
1425         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1426         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1427
1428         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1429                    !(status->rx_flags & IEEE80211_RX_RA_MATCH)))
1430                 return RX_CONTINUE;
1431
1432         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1433             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1434                 return RX_DROP_UNUSABLE;
1435
1436         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1437                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1438         else
1439                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1440
1441         /* Free PS Poll skb here instead of returning RX_DROP that would
1442          * count as an dropped frame. */
1443         dev_kfree_skb(rx->skb);
1444
1445         return RX_QUEUED;
1446 }
1447
1448 static ieee80211_rx_result debug_noinline
1449 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1450 {
1451         u8 *data = rx->skb->data;
1452         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1453
1454         if (!ieee80211_is_data_qos(hdr->frame_control))
1455                 return RX_CONTINUE;
1456
1457         /* remove the qos control field, update frame type and meta-data */
1458         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1459                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1460         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1461         /* change frame type to non QOS */
1462         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1463
1464         return RX_CONTINUE;
1465 }
1466
1467 static int
1468 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1469 {
1470         if (unlikely(!rx->sta ||
1471             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1472                 return -EACCES;
1473
1474         return 0;
1475 }
1476
1477 static int
1478 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1479 {
1480         struct sk_buff *skb = rx->skb;
1481         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1482
1483         /*
1484          * Pass through unencrypted frames if the hardware has
1485          * decrypted them already.
1486          */
1487         if (status->flag & RX_FLAG_DECRYPTED)
1488                 return 0;
1489
1490         /* Drop unencrypted frames if key is set. */
1491         if (unlikely(!ieee80211_has_protected(fc) &&
1492                      !ieee80211_is_nullfunc(fc) &&
1493                      ieee80211_is_data(fc) &&
1494                      (rx->key || rx->sdata->drop_unencrypted)))
1495                 return -EACCES;
1496
1497         return 0;
1498 }
1499
1500 static int
1501 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1502 {
1503         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1504         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1505         __le16 fc = hdr->frame_control;
1506
1507         /*
1508          * Pass through unencrypted frames if the hardware has
1509          * decrypted them already.
1510          */
1511         if (status->flag & RX_FLAG_DECRYPTED)
1512                 return 0;
1513
1514         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1515                 if (unlikely(!ieee80211_has_protected(fc) &&
1516                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1517                              rx->key)) {
1518                         if (ieee80211_is_deauth(fc))
1519                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1520                                                             rx->skb->data,
1521                                                             rx->skb->len);
1522                         else if (ieee80211_is_disassoc(fc))
1523                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1524                                                               rx->skb->data,
1525                                                               rx->skb->len);
1526                         return -EACCES;
1527                 }
1528                 /* BIP does not use Protected field, so need to check MMIE */
1529                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1530                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1531                         if (ieee80211_is_deauth(fc))
1532                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1533                                                             rx->skb->data,
1534                                                             rx->skb->len);
1535                         else if (ieee80211_is_disassoc(fc))
1536                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1537                                                               rx->skb->data,
1538                                                               rx->skb->len);
1539                         return -EACCES;
1540                 }
1541                 /*
1542                  * When using MFP, Action frames are not allowed prior to
1543                  * having configured keys.
1544                  */
1545                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1546                              ieee80211_is_robust_mgmt_frame(
1547                                      (struct ieee80211_hdr *) rx->skb->data)))
1548                         return -EACCES;
1549         }
1550
1551         return 0;
1552 }
1553
1554 static int
1555 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1556 {
1557         struct ieee80211_sub_if_data *sdata = rx->sdata;
1558         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1559
1560         if (ieee80211_has_a4(hdr->frame_control) &&
1561             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1562                 return -1;
1563
1564         if (is_multicast_ether_addr(hdr->addr1) &&
1565             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1566              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1567                 return -1;
1568
1569         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1570 }
1571
1572 /*
1573  * requires that rx->skb is a frame with ethernet header
1574  */
1575 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1576 {
1577         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1578                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1579         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1580
1581         /*
1582          * Allow EAPOL frames to us/the PAE group address regardless
1583          * of whether the frame was encrypted or not.
1584          */
1585         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1586             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1587              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1588                 return true;
1589
1590         if (ieee80211_802_1x_port_control(rx) ||
1591             ieee80211_drop_unencrypted(rx, fc))
1592                 return false;
1593
1594         return true;
1595 }
1596
1597 /*
1598  * requires that rx->skb is a frame with ethernet header
1599  */
1600 static void
1601 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1602 {
1603         struct ieee80211_sub_if_data *sdata = rx->sdata;
1604         struct net_device *dev = sdata->dev;
1605         struct sk_buff *skb, *xmit_skb;
1606         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1607         struct sta_info *dsta;
1608         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1609
1610         skb = rx->skb;
1611         xmit_skb = NULL;
1612
1613         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1614              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1615             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1616             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1617             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1618                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1619                         /*
1620                          * send multicast frames both to higher layers in
1621                          * local net stack and back to the wireless medium
1622                          */
1623                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1624                         if (!xmit_skb && net_ratelimit())
1625                                 printk(KERN_DEBUG "%s: failed to clone "
1626                                        "multicast frame\n", dev->name);
1627                 } else {
1628                         dsta = sta_info_get(sdata, skb->data);
1629                         if (dsta) {
1630                                 /*
1631                                  * The destination station is associated to
1632                                  * this AP (in this VLAN), so send the frame
1633                                  * directly to it and do not pass it to local
1634                                  * net stack.
1635                                  */
1636                                 xmit_skb = skb;
1637                                 skb = NULL;
1638                         }
1639                 }
1640         }
1641
1642         if (skb) {
1643                 int align __maybe_unused;
1644
1645 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1646                 /*
1647                  * 'align' will only take the values 0 or 2 here
1648                  * since all frames are required to be aligned
1649                  * to 2-byte boundaries when being passed to
1650                  * mac80211. That also explains the __skb_push()
1651                  * below.
1652                  */
1653                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1654                 if (align) {
1655                         if (WARN_ON(skb_headroom(skb) < 3)) {
1656                                 dev_kfree_skb(skb);
1657                                 skb = NULL;
1658                         } else {
1659                                 u8 *data = skb->data;
1660                                 size_t len = skb_headlen(skb);
1661                                 skb->data -= align;
1662                                 memmove(skb->data, data, len);
1663                                 skb_set_tail_pointer(skb, len);
1664                         }
1665                 }
1666 #endif
1667
1668                 if (skb) {
1669                         /* deliver to local stack */
1670                         skb->protocol = eth_type_trans(skb, dev);
1671                         memset(skb->cb, 0, sizeof(skb->cb));
1672                         netif_receive_skb(skb);
1673                 }
1674         }
1675
1676         if (xmit_skb) {
1677                 /* send to wireless media */
1678                 xmit_skb->protocol = htons(ETH_P_802_3);
1679                 skb_reset_network_header(xmit_skb);
1680                 skb_reset_mac_header(xmit_skb);
1681                 dev_queue_xmit(xmit_skb);
1682         }
1683 }
1684
1685 static ieee80211_rx_result debug_noinline
1686 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1687 {
1688         struct net_device *dev = rx->sdata->dev;
1689         struct sk_buff *skb = rx->skb;
1690         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1691         __le16 fc = hdr->frame_control;
1692         struct sk_buff_head frame_list;
1693         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1694
1695         if (unlikely(!ieee80211_is_data(fc)))
1696                 return RX_CONTINUE;
1697
1698         if (unlikely(!ieee80211_is_data_present(fc)))
1699                 return RX_DROP_MONITOR;
1700
1701         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1702                 return RX_CONTINUE;
1703
1704         if (ieee80211_has_a4(hdr->frame_control) &&
1705             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1706             !rx->sdata->u.vlan.sta)
1707                 return RX_DROP_UNUSABLE;
1708
1709         if (is_multicast_ether_addr(hdr->addr1) &&
1710             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1711               rx->sdata->u.vlan.sta) ||
1712              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1713               rx->sdata->u.mgd.use_4addr)))
1714                 return RX_DROP_UNUSABLE;
1715
1716         skb->dev = dev;
1717         __skb_queue_head_init(&frame_list);
1718
1719         if (skb_linearize(skb))
1720                 return RX_DROP_UNUSABLE;
1721
1722         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1723                                  rx->sdata->vif.type,
1724                                  rx->local->hw.extra_tx_headroom);
1725
1726         while (!skb_queue_empty(&frame_list)) {
1727                 rx->skb = __skb_dequeue(&frame_list);
1728
1729                 if (!ieee80211_frame_allowed(rx, fc)) {
1730                         dev_kfree_skb(rx->skb);
1731                         continue;
1732                 }
1733                 dev->stats.rx_packets++;
1734                 dev->stats.rx_bytes += rx->skb->len;
1735
1736                 ieee80211_deliver_skb(rx);
1737         }
1738
1739         return RX_QUEUED;
1740 }
1741
1742 #ifdef CONFIG_MAC80211_MESH
1743 static ieee80211_rx_result
1744 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1745 {
1746         struct ieee80211_hdr *hdr;
1747         struct ieee80211s_hdr *mesh_hdr;
1748         unsigned int hdrlen;
1749         struct sk_buff *skb = rx->skb, *fwd_skb;
1750         struct ieee80211_local *local = rx->local;
1751         struct ieee80211_sub_if_data *sdata = rx->sdata;
1752         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1753
1754         hdr = (struct ieee80211_hdr *) skb->data;
1755         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1756         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1757
1758         if (!ieee80211_is_data(hdr->frame_control))
1759                 return RX_CONTINUE;
1760
1761         if (!mesh_hdr->ttl)
1762                 /* illegal frame */
1763                 return RX_DROP_MONITOR;
1764
1765         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1766                 struct mesh_path *mppath;
1767                 char *proxied_addr;
1768                 char *mpp_addr;
1769
1770                 if (is_multicast_ether_addr(hdr->addr1)) {
1771                         mpp_addr = hdr->addr3;
1772                         proxied_addr = mesh_hdr->eaddr1;
1773                 } else {
1774                         mpp_addr = hdr->addr4;
1775                         proxied_addr = mesh_hdr->eaddr2;
1776                 }
1777
1778                 rcu_read_lock();
1779                 mppath = mpp_path_lookup(proxied_addr, sdata);
1780                 if (!mppath) {
1781                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1782                 } else {
1783                         spin_lock_bh(&mppath->state_lock);
1784                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1785                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1786                         spin_unlock_bh(&mppath->state_lock);
1787                 }
1788                 rcu_read_unlock();
1789         }
1790
1791         /* Frame has reached destination.  Don't forward */
1792         if (!is_multicast_ether_addr(hdr->addr1) &&
1793             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1794                 return RX_CONTINUE;
1795
1796         mesh_hdr->ttl--;
1797
1798         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1799                 if (!mesh_hdr->ttl)
1800                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1801                                                      dropped_frames_ttl);
1802                 else {
1803                         struct ieee80211_hdr *fwd_hdr;
1804                         struct ieee80211_tx_info *info;
1805
1806                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1807
1808                         if (!fwd_skb && net_ratelimit())
1809                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1810                                                    sdata->name);
1811                         if (!fwd_skb)
1812                                 goto out;
1813
1814                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1815                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1816                         info = IEEE80211_SKB_CB(fwd_skb);
1817                         memset(info, 0, sizeof(*info));
1818                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1819                         info->control.vif = &rx->sdata->vif;
1820                         skb_set_queue_mapping(skb,
1821                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1822                         ieee80211_set_qos_hdr(local, skb);
1823                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1824                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1825                                                                 fwded_mcast);
1826                         else {
1827                                 int err;
1828                                 /*
1829                                  * Save TA to addr1 to send TA a path error if a
1830                                  * suitable next hop is not found
1831                                  */
1832                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1833                                                 ETH_ALEN);
1834                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1835                                 /* Failed to immediately resolve next hop:
1836                                  * fwded frame was dropped or will be added
1837                                  * later to the pending skb queue.  */
1838                                 if (err)
1839                                         return RX_DROP_MONITOR;
1840
1841                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1842                                                                 fwded_unicast);
1843                         }
1844                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1845                                                      fwded_frames);
1846                         ieee80211_add_pending_skb(local, fwd_skb);
1847                 }
1848         }
1849
1850  out:
1851         if (is_multicast_ether_addr(hdr->addr1) ||
1852             sdata->dev->flags & IFF_PROMISC)
1853                 return RX_CONTINUE;
1854         else
1855                 return RX_DROP_MONITOR;
1856 }
1857 #endif
1858
1859 static ieee80211_rx_result debug_noinline
1860 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1861 {
1862         struct ieee80211_sub_if_data *sdata = rx->sdata;
1863         struct ieee80211_local *local = rx->local;
1864         struct net_device *dev = sdata->dev;
1865         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1866         __le16 fc = hdr->frame_control;
1867         int err;
1868
1869         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1870                 return RX_CONTINUE;
1871
1872         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1873                 return RX_DROP_MONITOR;
1874
1875         /*
1876          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1877          * that a 4-addr station can be detected and moved into a separate VLAN
1878          */
1879         if (ieee80211_has_a4(hdr->frame_control) &&
1880             sdata->vif.type == NL80211_IFTYPE_AP)
1881                 return RX_DROP_MONITOR;
1882
1883         err = __ieee80211_data_to_8023(rx);
1884         if (unlikely(err))
1885                 return RX_DROP_UNUSABLE;
1886
1887         if (!ieee80211_frame_allowed(rx, fc))
1888                 return RX_DROP_MONITOR;
1889
1890         rx->skb->dev = dev;
1891
1892         dev->stats.rx_packets++;
1893         dev->stats.rx_bytes += rx->skb->len;
1894
1895         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
1896             !is_multicast_ether_addr(((struct ethhdr *)rx->skb->data)->h_dest)) {
1897                         mod_timer(&local->dynamic_ps_timer, jiffies +
1898                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1899         }
1900
1901         ieee80211_deliver_skb(rx);
1902
1903         return RX_QUEUED;
1904 }
1905
1906 static ieee80211_rx_result debug_noinline
1907 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1908 {
1909         struct ieee80211_local *local = rx->local;
1910         struct ieee80211_hw *hw = &local->hw;
1911         struct sk_buff *skb = rx->skb;
1912         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1913         struct tid_ampdu_rx *tid_agg_rx;
1914         u16 start_seq_num;
1915         u16 tid;
1916
1917         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1918                 return RX_CONTINUE;
1919
1920         if (ieee80211_is_back_req(bar->frame_control)) {
1921                 struct {
1922                         __le16 control, start_seq_num;
1923                 } __packed bar_data;
1924
1925                 if (!rx->sta)
1926                         return RX_DROP_MONITOR;
1927
1928                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1929                                   &bar_data, sizeof(bar_data)))
1930                         return RX_DROP_MONITOR;
1931
1932                 tid = le16_to_cpu(bar_data.control) >> 12;
1933
1934                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1935                 if (!tid_agg_rx)
1936                         return RX_DROP_MONITOR;
1937
1938                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1939
1940                 /* reset session timer */
1941                 if (tid_agg_rx->timeout)
1942                         mod_timer(&tid_agg_rx->session_timer,
1943                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1944
1945                 spin_lock(&tid_agg_rx->reorder_lock);
1946                 /* release stored frames up to start of BAR */
1947                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
1948                 spin_unlock(&tid_agg_rx->reorder_lock);
1949
1950                 kfree_skb(skb);
1951                 return RX_QUEUED;
1952         }
1953
1954         /*
1955          * After this point, we only want management frames,
1956          * so we can drop all remaining control frames to
1957          * cooked monitor interfaces.
1958          */
1959         return RX_DROP_MONITOR;
1960 }
1961
1962 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1963                                            struct ieee80211_mgmt *mgmt,
1964                                            size_t len)
1965 {
1966         struct ieee80211_local *local = sdata->local;
1967         struct sk_buff *skb;
1968         struct ieee80211_mgmt *resp;
1969
1970         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1971                 /* Not to own unicast address */
1972                 return;
1973         }
1974
1975         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1976             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1977                 /* Not from the current AP or not associated yet. */
1978                 return;
1979         }
1980
1981         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1982                 /* Too short SA Query request frame */
1983                 return;
1984         }
1985
1986         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1987         if (skb == NULL)
1988                 return;
1989
1990         skb_reserve(skb, local->hw.extra_tx_headroom);
1991         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1992         memset(resp, 0, 24);
1993         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1994         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1995         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1996         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1997                                           IEEE80211_STYPE_ACTION);
1998         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1999         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2000         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2001         memcpy(resp->u.action.u.sa_query.trans_id,
2002                mgmt->u.action.u.sa_query.trans_id,
2003                WLAN_SA_QUERY_TR_ID_LEN);
2004
2005         ieee80211_tx_skb(sdata, skb);
2006 }
2007
2008 static ieee80211_rx_result debug_noinline
2009 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2010 {
2011         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2012         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2013
2014         /*
2015          * From here on, look only at management frames.
2016          * Data and control frames are already handled,
2017          * and unknown (reserved) frames are useless.
2018          */
2019         if (rx->skb->len < 24)
2020                 return RX_DROP_MONITOR;
2021
2022         if (!ieee80211_is_mgmt(mgmt->frame_control))
2023                 return RX_DROP_MONITOR;
2024
2025         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2026                 return RX_DROP_MONITOR;
2027
2028         if (ieee80211_drop_unencrypted_mgmt(rx))
2029                 return RX_DROP_UNUSABLE;
2030
2031         return RX_CONTINUE;
2032 }
2033
2034 static ieee80211_rx_result debug_noinline
2035 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2036 {
2037         struct ieee80211_local *local = rx->local;
2038         struct ieee80211_sub_if_data *sdata = rx->sdata;
2039         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2040         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2041         int len = rx->skb->len;
2042
2043         if (!ieee80211_is_action(mgmt->frame_control))
2044                 return RX_CONTINUE;
2045
2046         /* drop too small frames */
2047         if (len < IEEE80211_MIN_ACTION_SIZE)
2048                 return RX_DROP_UNUSABLE;
2049
2050         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2051                 return RX_DROP_UNUSABLE;
2052
2053         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2054                 return RX_DROP_UNUSABLE;
2055
2056         switch (mgmt->u.action.category) {
2057         case WLAN_CATEGORY_BACK:
2058                 /*
2059                  * The aggregation code is not prepared to handle
2060                  * anything but STA/AP due to the BSSID handling;
2061                  * IBSS could work in the code but isn't supported
2062                  * by drivers or the standard.
2063                  */
2064                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2065                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2066                     sdata->vif.type != NL80211_IFTYPE_AP)
2067                         break;
2068
2069                 /* verify action_code is present */
2070                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2071                         break;
2072
2073                 switch (mgmt->u.action.u.addba_req.action_code) {
2074                 case WLAN_ACTION_ADDBA_REQ:
2075                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2076                                    sizeof(mgmt->u.action.u.addba_req)))
2077                                 goto invalid;
2078                         break;
2079                 case WLAN_ACTION_ADDBA_RESP:
2080                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2081                                    sizeof(mgmt->u.action.u.addba_resp)))
2082                                 goto invalid;
2083                         break;
2084                 case WLAN_ACTION_DELBA:
2085                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2086                                    sizeof(mgmt->u.action.u.delba)))
2087                                 goto invalid;
2088                         break;
2089                 default:
2090                         goto invalid;
2091                 }
2092
2093                 goto queue;
2094         case WLAN_CATEGORY_SPECTRUM_MGMT:
2095                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2096                         break;
2097
2098                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2099                         break;
2100
2101                 /* verify action_code is present */
2102                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2103                         break;
2104
2105                 switch (mgmt->u.action.u.measurement.action_code) {
2106                 case WLAN_ACTION_SPCT_MSR_REQ:
2107                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2108                                    sizeof(mgmt->u.action.u.measurement)))
2109                                 break;
2110                         ieee80211_process_measurement_req(sdata, mgmt, len);
2111                         goto handled;
2112                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2113                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2114                                    sizeof(mgmt->u.action.u.chan_switch)))
2115                                 break;
2116
2117                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2118                                 break;
2119
2120                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2121                                 break;
2122
2123                         goto queue;
2124                 }
2125                 break;
2126         case WLAN_CATEGORY_SA_QUERY:
2127                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2128                            sizeof(mgmt->u.action.u.sa_query)))
2129                         break;
2130
2131                 switch (mgmt->u.action.u.sa_query.action) {
2132                 case WLAN_ACTION_SA_QUERY_REQUEST:
2133                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2134                                 break;
2135                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2136                         goto handled;
2137                 }
2138                 break;
2139         case WLAN_CATEGORY_MESH_PLINK:
2140                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2141                         break;
2142                 goto queue;
2143         case WLAN_CATEGORY_MESH_PATH_SEL:
2144                 if (!mesh_path_sel_is_hwmp(sdata))
2145                         break;
2146                 goto queue;
2147         }
2148
2149         return RX_CONTINUE;
2150
2151  invalid:
2152         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2153         /* will return in the next handlers */
2154         return RX_CONTINUE;
2155
2156  handled:
2157         if (rx->sta)
2158                 rx->sta->rx_packets++;
2159         dev_kfree_skb(rx->skb);
2160         return RX_QUEUED;
2161
2162  queue:
2163         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2164         skb_queue_tail(&sdata->skb_queue, rx->skb);
2165         ieee80211_queue_work(&local->hw, &sdata->work);
2166         if (rx->sta)
2167                 rx->sta->rx_packets++;
2168         return RX_QUEUED;
2169 }
2170
2171 static ieee80211_rx_result debug_noinline
2172 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2173 {
2174         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2175
2176         /* skip known-bad action frames and return them in the next handler */
2177         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2178                 return RX_CONTINUE;
2179
2180         /*
2181          * Getting here means the kernel doesn't know how to handle
2182          * it, but maybe userspace does ... include returned frames
2183          * so userspace can register for those to know whether ones
2184          * it transmitted were processed or returned.
2185          */
2186
2187         if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2188                              rx->skb->data, rx->skb->len,
2189                              GFP_ATOMIC)) {
2190                 if (rx->sta)
2191                         rx->sta->rx_packets++;
2192                 dev_kfree_skb(rx->skb);
2193                 return RX_QUEUED;
2194         }
2195
2196
2197         return RX_CONTINUE;
2198 }
2199
2200 static ieee80211_rx_result debug_noinline
2201 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2202 {
2203         struct ieee80211_local *local = rx->local;
2204         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2205         struct sk_buff *nskb;
2206         struct ieee80211_sub_if_data *sdata = rx->sdata;
2207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2208
2209         if (!ieee80211_is_action(mgmt->frame_control))
2210                 return RX_CONTINUE;
2211
2212         /*
2213          * For AP mode, hostapd is responsible for handling any action
2214          * frames that we didn't handle, including returning unknown
2215          * ones. For all other modes we will return them to the sender,
2216          * setting the 0x80 bit in the action category, as required by
2217          * 802.11-2007 7.3.1.11.
2218          * Newer versions of hostapd shall also use the management frame
2219          * registration mechanisms, but older ones still use cooked
2220          * monitor interfaces so push all frames there.
2221          */
2222         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2223             (sdata->vif.type == NL80211_IFTYPE_AP ||
2224              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2225                 return RX_DROP_MONITOR;
2226
2227         /* do not return rejected action frames */
2228         if (mgmt->u.action.category & 0x80)
2229                 return RX_DROP_UNUSABLE;
2230
2231         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2232                                GFP_ATOMIC);
2233         if (nskb) {
2234                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2235
2236                 nmgmt->u.action.category |= 0x80;
2237                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2238                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2239
2240                 memset(nskb->cb, 0, sizeof(nskb->cb));
2241
2242                 ieee80211_tx_skb(rx->sdata, nskb);
2243         }
2244         dev_kfree_skb(rx->skb);
2245         return RX_QUEUED;
2246 }
2247
2248 static ieee80211_rx_result debug_noinline
2249 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2250 {
2251         struct ieee80211_sub_if_data *sdata = rx->sdata;
2252         ieee80211_rx_result rxs;
2253         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2254         __le16 stype;
2255
2256         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2257         if (rxs != RX_CONTINUE)
2258                 return rxs;
2259
2260         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2261
2262         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2263             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2264             sdata->vif.type != NL80211_IFTYPE_STATION)
2265                 return RX_DROP_MONITOR;
2266
2267         switch (stype) {
2268         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2269         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2270                 /* process for all: mesh, mlme, ibss */
2271                 break;
2272         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2273         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2274                 if (is_multicast_ether_addr(mgmt->da) &&
2275                     !is_broadcast_ether_addr(mgmt->da))
2276                         return RX_DROP_MONITOR;
2277
2278                 /* process only for station */
2279                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2280                         return RX_DROP_MONITOR;
2281                 break;
2282         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2283         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2284                 /* process only for ibss */
2285                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2286                         return RX_DROP_MONITOR;
2287                 break;
2288         default:
2289                 return RX_DROP_MONITOR;
2290         }
2291
2292         /* queue up frame and kick off work to process it */
2293         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2294         skb_queue_tail(&sdata->skb_queue, rx->skb);
2295         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2296         if (rx->sta)
2297                 rx->sta->rx_packets++;
2298
2299         return RX_QUEUED;
2300 }
2301
2302 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2303                                             struct ieee80211_rx_data *rx)
2304 {
2305         int keyidx;
2306         unsigned int hdrlen;
2307
2308         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2309         if (rx->skb->len >= hdrlen + 4)
2310                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2311         else
2312                 keyidx = -1;
2313
2314         if (!rx->sta) {
2315                 /*
2316                  * Some hardware seem to generate incorrect Michael MIC
2317                  * reports; ignore them to avoid triggering countermeasures.
2318                  */
2319                 return;
2320         }
2321
2322         if (!ieee80211_has_protected(hdr->frame_control))
2323                 return;
2324
2325         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2326                 /*
2327                  * APs with pairwise keys should never receive Michael MIC
2328                  * errors for non-zero keyidx because these are reserved for
2329                  * group keys and only the AP is sending real multicast
2330                  * frames in the BSS.
2331                  */
2332                 return;
2333         }
2334
2335         if (!ieee80211_is_data(hdr->frame_control) &&
2336             !ieee80211_is_auth(hdr->frame_control))
2337                 return;
2338
2339         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2340                                         GFP_ATOMIC);
2341 }
2342
2343 /* TODO: use IEEE80211_RX_FRAGMENTED */
2344 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2345                                         struct ieee80211_rate *rate)
2346 {
2347         struct ieee80211_sub_if_data *sdata;
2348         struct ieee80211_local *local = rx->local;
2349         struct ieee80211_rtap_hdr {
2350                 struct ieee80211_radiotap_header hdr;
2351                 u8 flags;
2352                 u8 rate_or_pad;
2353                 __le16 chan_freq;
2354                 __le16 chan_flags;
2355         } __packed *rthdr;
2356         struct sk_buff *skb = rx->skb, *skb2;
2357         struct net_device *prev_dev = NULL;
2358         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2359
2360         /*
2361          * If cooked monitor has been processed already, then
2362          * don't do it again. If not, set the flag.
2363          */
2364         if (rx->flags & IEEE80211_RX_CMNTR)
2365                 goto out_free_skb;
2366         rx->flags |= IEEE80211_RX_CMNTR;
2367
2368         if (skb_headroom(skb) < sizeof(*rthdr) &&
2369             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2370                 goto out_free_skb;
2371
2372         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2373         memset(rthdr, 0, sizeof(*rthdr));
2374         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2375         rthdr->hdr.it_present =
2376                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2377                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2378
2379         if (rate) {
2380                 rthdr->rate_or_pad = rate->bitrate / 5;
2381                 rthdr->hdr.it_present |=
2382                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2383         }
2384         rthdr->chan_freq = cpu_to_le16(status->freq);
2385
2386         if (status->band == IEEE80211_BAND_5GHZ)
2387                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2388                                                 IEEE80211_CHAN_5GHZ);
2389         else
2390                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2391                                                 IEEE80211_CHAN_2GHZ);
2392
2393         skb_set_mac_header(skb, 0);
2394         skb->ip_summed = CHECKSUM_UNNECESSARY;
2395         skb->pkt_type = PACKET_OTHERHOST;
2396         skb->protocol = htons(ETH_P_802_2);
2397
2398         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2399                 if (!ieee80211_sdata_running(sdata))
2400                         continue;
2401
2402                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2403                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2404                         continue;
2405
2406                 if (prev_dev) {
2407                         skb2 = skb_clone(skb, GFP_ATOMIC);
2408                         if (skb2) {
2409                                 skb2->dev = prev_dev;
2410                                 netif_receive_skb(skb2);
2411                         }
2412                 }
2413
2414                 prev_dev = sdata->dev;
2415                 sdata->dev->stats.rx_packets++;
2416                 sdata->dev->stats.rx_bytes += skb->len;
2417         }
2418
2419         if (prev_dev) {
2420                 skb->dev = prev_dev;
2421                 netif_receive_skb(skb);
2422                 return;
2423         }
2424
2425  out_free_skb:
2426         dev_kfree_skb(skb);
2427 }
2428
2429 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2430                                          ieee80211_rx_result res)
2431 {
2432         switch (res) {
2433         case RX_DROP_MONITOR:
2434                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2435                 if (rx->sta)
2436                         rx->sta->rx_dropped++;
2437                 /* fall through */
2438         case RX_CONTINUE: {
2439                 struct ieee80211_rate *rate = NULL;
2440                 struct ieee80211_supported_band *sband;
2441                 struct ieee80211_rx_status *status;
2442
2443                 status = IEEE80211_SKB_RXCB((rx->skb));
2444
2445                 sband = rx->local->hw.wiphy->bands[status->band];
2446                 if (!(status->flag & RX_FLAG_HT))
2447                         rate = &sband->bitrates[status->rate_idx];
2448
2449                 ieee80211_rx_cooked_monitor(rx, rate);
2450                 break;
2451                 }
2452         case RX_DROP_UNUSABLE:
2453                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2454                 if (rx->sta)
2455                         rx->sta->rx_dropped++;
2456                 dev_kfree_skb(rx->skb);
2457                 break;
2458         case RX_QUEUED:
2459                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2460                 break;
2461         }
2462 }
2463
2464 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2465 {
2466         ieee80211_rx_result res = RX_DROP_MONITOR;
2467         struct sk_buff *skb;
2468
2469 #define CALL_RXH(rxh)                   \
2470         do {                            \
2471                 res = rxh(rx);          \
2472                 if (res != RX_CONTINUE) \
2473                         goto rxh_next;  \
2474         } while (0);
2475
2476         spin_lock(&rx->local->rx_skb_queue.lock);
2477         if (rx->local->running_rx_handler)
2478                 goto unlock;
2479
2480         rx->local->running_rx_handler = true;
2481
2482         while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2483                 spin_unlock(&rx->local->rx_skb_queue.lock);
2484
2485                 /*
2486                  * all the other fields are valid across frames
2487                  * that belong to an aMPDU since they are on the
2488                  * same TID from the same station
2489                  */
2490                 rx->skb = skb;
2491                 rx->flags = 0;
2492
2493                 CALL_RXH(ieee80211_rx_h_decrypt)
2494                 CALL_RXH(ieee80211_rx_h_check_more_data)
2495                 CALL_RXH(ieee80211_rx_h_sta_process)
2496                 CALL_RXH(ieee80211_rx_h_defragment)
2497                 CALL_RXH(ieee80211_rx_h_ps_poll)
2498                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2499                 /* must be after MMIC verify so header is counted in MPDU mic */
2500                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2501                 CALL_RXH(ieee80211_rx_h_amsdu)
2502 #ifdef CONFIG_MAC80211_MESH
2503                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2504                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2505 #endif
2506                 CALL_RXH(ieee80211_rx_h_data)
2507                 CALL_RXH(ieee80211_rx_h_ctrl);
2508                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2509                 CALL_RXH(ieee80211_rx_h_action)
2510                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2511                 CALL_RXH(ieee80211_rx_h_action_return)
2512                 CALL_RXH(ieee80211_rx_h_mgmt)
2513
2514  rxh_next:
2515                 ieee80211_rx_handlers_result(rx, res);
2516                 spin_lock(&rx->local->rx_skb_queue.lock);
2517 #undef CALL_RXH
2518         }
2519
2520         rx->local->running_rx_handler = false;
2521
2522  unlock:
2523         spin_unlock(&rx->local->rx_skb_queue.lock);
2524 }
2525
2526 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2527 {
2528         ieee80211_rx_result res = RX_DROP_MONITOR;
2529
2530 #define CALL_RXH(rxh)                   \
2531         do {                            \
2532                 res = rxh(rx);          \
2533                 if (res != RX_CONTINUE) \
2534                         goto rxh_next;  \
2535         } while (0);
2536
2537         CALL_RXH(ieee80211_rx_h_passive_scan)
2538         CALL_RXH(ieee80211_rx_h_check)
2539
2540         ieee80211_rx_reorder_ampdu(rx);
2541
2542         ieee80211_rx_handlers(rx);
2543         return;
2544
2545  rxh_next:
2546         ieee80211_rx_handlers_result(rx, res);
2547
2548 #undef CALL_RXH
2549 }
2550
2551 /*
2552  * This function makes calls into the RX path, therefore
2553  * it has to be invoked under RCU read lock.
2554  */
2555 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2556 {
2557         struct ieee80211_rx_data rx = {
2558                 .sta = sta,
2559                 .sdata = sta->sdata,
2560                 .local = sta->local,
2561                 .queue = tid,
2562         };
2563         struct tid_ampdu_rx *tid_agg_rx;
2564
2565         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2566         if (!tid_agg_rx)
2567                 return;
2568
2569         spin_lock(&tid_agg_rx->reorder_lock);
2570         ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
2571         spin_unlock(&tid_agg_rx->reorder_lock);
2572
2573         ieee80211_rx_handlers(&rx);
2574 }
2575
2576 /* main receive path */
2577
2578 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2579                                 struct ieee80211_hdr *hdr)
2580 {
2581         struct ieee80211_sub_if_data *sdata = rx->sdata;
2582         struct sk_buff *skb = rx->skb;
2583         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2584         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2585         int multicast = is_multicast_ether_addr(hdr->addr1);
2586
2587         switch (sdata->vif.type) {
2588         case NL80211_IFTYPE_STATION:
2589                 if (!bssid && !sdata->u.mgd.use_4addr)
2590                         return 0;
2591                 if (!multicast &&
2592                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2593                         if (!(sdata->dev->flags & IFF_PROMISC))
2594                                 return 0;
2595                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2596                 }
2597                 break;
2598         case NL80211_IFTYPE_ADHOC:
2599                 if (!bssid)
2600                         return 0;
2601                 if (ieee80211_is_beacon(hdr->frame_control)) {
2602                         return 1;
2603                 }
2604                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2605                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2606                                 return 0;
2607                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2608                 } else if (!multicast &&
2609                            compare_ether_addr(sdata->vif.addr,
2610                                               hdr->addr1) != 0) {
2611                         if (!(sdata->dev->flags & IFF_PROMISC))
2612                                 return 0;
2613                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2614                 } else if (!rx->sta) {
2615                         int rate_idx;
2616                         if (status->flag & RX_FLAG_HT)
2617                                 rate_idx = 0; /* TODO: HT rates */
2618                         else
2619                                 rate_idx = status->rate_idx;
2620                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2621                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2622                 }
2623                 break;
2624         case NL80211_IFTYPE_MESH_POINT:
2625                 if (!multicast &&
2626                     compare_ether_addr(sdata->vif.addr,
2627                                        hdr->addr1) != 0) {
2628                         if (!(sdata->dev->flags & IFF_PROMISC))
2629                                 return 0;
2630
2631                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2632                 }
2633                 break;
2634         case NL80211_IFTYPE_AP_VLAN:
2635         case NL80211_IFTYPE_AP:
2636                 if (!bssid) {
2637                         if (compare_ether_addr(sdata->vif.addr,
2638                                                hdr->addr1))
2639                                 return 0;
2640                 } else if (!ieee80211_bssid_match(bssid,
2641                                         sdata->vif.addr)) {
2642                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2643                                 return 0;
2644                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2645                 }
2646                 break;
2647         case NL80211_IFTYPE_WDS:
2648                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2649                         return 0;
2650                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2651                         return 0;
2652                 break;
2653         default:
2654                 /* should never get here */
2655                 WARN_ON(1);
2656                 break;
2657         }
2658
2659         return 1;
2660 }
2661
2662 /*
2663  * This function returns whether or not the SKB
2664  * was destined for RX processing or not, which,
2665  * if consume is true, is equivalent to whether
2666  * or not the skb was consumed.
2667  */
2668 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2669                                             struct sk_buff *skb, bool consume)
2670 {
2671         struct ieee80211_local *local = rx->local;
2672         struct ieee80211_sub_if_data *sdata = rx->sdata;
2673         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2674         struct ieee80211_hdr *hdr = (void *)skb->data;
2675         int prepares;
2676
2677         rx->skb = skb;
2678         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2679         prepares = prepare_for_handlers(rx, hdr);
2680
2681         if (!prepares)
2682                 return false;
2683
2684         if (status->flag & RX_FLAG_MMIC_ERROR) {
2685                 if (status->rx_flags & IEEE80211_RX_RA_MATCH)
2686                         ieee80211_rx_michael_mic_report(hdr, rx);
2687                 return false;
2688         }
2689
2690         if (!consume) {
2691                 skb = skb_copy(skb, GFP_ATOMIC);
2692                 if (!skb) {
2693                         if (net_ratelimit())
2694                                 wiphy_debug(local->hw.wiphy,
2695                                         "failed to copy multicast frame for %s\n",
2696                                         sdata->name);
2697                         return true;
2698                 }
2699
2700                 rx->skb = skb;
2701         }
2702
2703         ieee80211_invoke_rx_handlers(rx);
2704         return true;
2705 }
2706
2707 /*
2708  * This is the actual Rx frames handler. as it blongs to Rx path it must
2709  * be called with rcu_read_lock protection.
2710  */
2711 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2712                                          struct sk_buff *skb)
2713 {
2714         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2715         struct ieee80211_local *local = hw_to_local(hw);
2716         struct ieee80211_sub_if_data *sdata;
2717         struct ieee80211_hdr *hdr;
2718         __le16 fc;
2719         struct ieee80211_rx_data rx;
2720         struct ieee80211_sub_if_data *prev;
2721         struct sta_info *sta, *tmp, *prev_sta;
2722         int err = 0;
2723
2724         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2725         memset(&rx, 0, sizeof(rx));
2726         rx.skb = skb;
2727         rx.local = local;
2728
2729         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2730                 local->dot11ReceivedFragmentCount++;
2731
2732         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2733                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2734                 status->rx_flags |= IEEE80211_RX_IN_SCAN;
2735
2736         if (ieee80211_is_mgmt(fc))
2737                 err = skb_linearize(skb);
2738         else
2739                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2740
2741         if (err) {
2742                 dev_kfree_skb(skb);
2743                 return;
2744         }
2745
2746         hdr = (struct ieee80211_hdr *)skb->data;
2747         ieee80211_parse_qos(&rx);
2748         ieee80211_verify_alignment(&rx);
2749
2750         if (ieee80211_is_data(fc)) {
2751                 prev_sta = NULL;
2752
2753                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2754                         if (!prev_sta) {
2755                                 prev_sta = sta;
2756                                 continue;
2757                         }
2758
2759                         rx.sta = prev_sta;
2760                         rx.sdata = prev_sta->sdata;
2761                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2762
2763                         prev_sta = sta;
2764                 }
2765
2766                 if (prev_sta) {
2767                         rx.sta = prev_sta;
2768                         rx.sdata = prev_sta->sdata;
2769
2770                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2771                                 return;
2772                         goto out;
2773                 }
2774         }
2775
2776         prev = NULL;
2777
2778         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2779                 if (!ieee80211_sdata_running(sdata))
2780                         continue;
2781
2782                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2783                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2784                         continue;
2785
2786                 /*
2787                  * frame is destined for this interface, but if it's
2788                  * not also for the previous one we handle that after
2789                  * the loop to avoid copying the SKB once too much
2790                  */
2791
2792                 if (!prev) {
2793                         prev = sdata;
2794                         continue;
2795                 }
2796
2797                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2798                 rx.sdata = prev;
2799                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2800
2801                 prev = sdata;
2802         }
2803
2804         if (prev) {
2805                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2806                 rx.sdata = prev;
2807
2808                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2809                         return;
2810         }
2811
2812  out:
2813         dev_kfree_skb(skb);
2814 }
2815
2816 /*
2817  * This is the receive path handler. It is called by a low level driver when an
2818  * 802.11 MPDU is received from the hardware.
2819  */
2820 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2821 {
2822         struct ieee80211_local *local = hw_to_local(hw);
2823         struct ieee80211_rate *rate = NULL;
2824         struct ieee80211_supported_band *sband;
2825         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2826
2827         WARN_ON_ONCE(softirq_count() == 0);
2828
2829         if (WARN_ON(status->band < 0 ||
2830                     status->band >= IEEE80211_NUM_BANDS))
2831                 goto drop;
2832
2833         sband = local->hw.wiphy->bands[status->band];
2834         if (WARN_ON(!sband))
2835                 goto drop;
2836
2837         /*
2838          * If we're suspending, it is possible although not too likely
2839          * that we'd be receiving frames after having already partially
2840          * quiesced the stack. We can't process such frames then since
2841          * that might, for example, cause stations to be added or other
2842          * driver callbacks be invoked.
2843          */
2844         if (unlikely(local->quiescing || local->suspended))
2845                 goto drop;
2846
2847         /*
2848          * The same happens when we're not even started,
2849          * but that's worth a warning.
2850          */
2851         if (WARN_ON(!local->started))
2852                 goto drop;
2853
2854         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2855                 /*
2856                  * Validate the rate, unless a PLCP error means that
2857                  * we probably can't have a valid rate here anyway.
2858                  */
2859
2860                 if (status->flag & RX_FLAG_HT) {
2861                         /*
2862                          * rate_idx is MCS index, which can be [0-76]
2863                          * as documented on:
2864                          *
2865                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2866                          *
2867                          * Anything else would be some sort of driver or
2868                          * hardware error. The driver should catch hardware
2869                          * errors.
2870                          */
2871                         if (WARN((status->rate_idx < 0 ||
2872                                  status->rate_idx > 76),
2873                                  "Rate marked as an HT rate but passed "
2874                                  "status->rate_idx is not "
2875                                  "an MCS index [0-76]: %d (0x%02x)\n",
2876                                  status->rate_idx,
2877                                  status->rate_idx))
2878                                 goto drop;
2879                 } else {
2880                         if (WARN_ON(status->rate_idx < 0 ||
2881                                     status->rate_idx >= sband->n_bitrates))
2882                                 goto drop;
2883                         rate = &sband->bitrates[status->rate_idx];
2884                 }
2885         }
2886
2887         status->rx_flags = 0;
2888
2889         /*
2890          * key references and virtual interfaces are protected using RCU
2891          * and this requires that we are in a read-side RCU section during
2892          * receive processing
2893          */
2894         rcu_read_lock();
2895
2896         /*
2897          * Frames with failed FCS/PLCP checksum are not returned,
2898          * all other frames are returned without radiotap header
2899          * if it was previously present.
2900          * Also, frames with less than 16 bytes are dropped.
2901          */
2902         skb = ieee80211_rx_monitor(local, skb, rate);
2903         if (!skb) {
2904                 rcu_read_unlock();
2905                 return;
2906         }
2907
2908         ieee80211_tpt_led_trig_rx(local,
2909                         ((struct ieee80211_hdr *)skb->data)->frame_control,
2910                         skb->len);
2911         __ieee80211_rx_handle_packet(hw, skb);
2912
2913         rcu_read_unlock();
2914
2915         return;
2916  drop:
2917         kfree_skb(skb);
2918 }
2919 EXPORT_SYMBOL(ieee80211_rx);
2920
2921 /* This is a version of the rx handler that can be called from hard irq
2922  * context. Post the skb on the queue and schedule the tasklet */
2923 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2924 {
2925         struct ieee80211_local *local = hw_to_local(hw);
2926
2927         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2928
2929         skb->pkt_type = IEEE80211_RX_MSG;
2930         skb_queue_tail(&local->skb_queue, skb);
2931         tasklet_schedule(&local->tasklet);
2932 }
2933 EXPORT_SYMBOL(ieee80211_rx_irqsafe);