Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[pandora-kernel.git] / net / mac80211 / rx.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <net/mac80211.h>
20 #include <net/ieee80211_radiotap.h>
21
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "led.h"
25 #include "mesh.h"
26 #include "wep.h"
27 #include "wpa.h"
28 #include "tkip.h"
29 #include "wme.h"
30
31 /*
32  * monitor mode reception
33  *
34  * This function cleans up the SKB, i.e. it removes all the stuff
35  * only useful for monitoring.
36  */
37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
38                                            struct sk_buff *skb)
39 {
40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
41                 if (likely(skb->len > FCS_LEN))
42                         __pskb_trim(skb, skb->len - FCS_LEN);
43                 else {
44                         /* driver bug */
45                         WARN_ON(1);
46                         dev_kfree_skb(skb);
47                         skb = NULL;
48                 }
49         }
50
51         return skb;
52 }
53
54 static inline int should_drop_frame(struct sk_buff *skb,
55                                     int present_fcs_len)
56 {
57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
59
60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
61                 return 1;
62         if (unlikely(skb->len < 16 + present_fcs_len))
63                 return 1;
64         if (ieee80211_is_ctl(hdr->frame_control) &&
65             !ieee80211_is_pspoll(hdr->frame_control) &&
66             !ieee80211_is_back_req(hdr->frame_control))
67                 return 1;
68         return 0;
69 }
70
71 static int
72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
73                           struct ieee80211_rx_status *status)
74 {
75         int len;
76
77         /* always present fields */
78         len = sizeof(struct ieee80211_radiotap_header) + 9;
79
80         if (status->flag & RX_FLAG_TSFT)
81                 len += 8;
82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
83                 len += 1;
84
85         if (len & 1) /* padding for RX_FLAGS if necessary */
86                 len++;
87
88         return len;
89 }
90
91 /*
92  * ieee80211_add_rx_radiotap_header - add radiotap header
93  *
94  * add a radiotap header containing all the fields which the hardware provided.
95  */
96 static void
97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
98                                  struct sk_buff *skb,
99                                  struct ieee80211_rate *rate,
100                                  int rtap_len)
101 {
102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
103         struct ieee80211_radiotap_header *rthdr;
104         unsigned char *pos;
105         u16 rx_flags = 0;
106
107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
108         memset(rthdr, 0, rtap_len);
109
110         /* radiotap header, set always present flags */
111         rthdr->it_present =
112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
116         rthdr->it_len = cpu_to_le16(rtap_len);
117
118         pos = (unsigned char *)(rthdr+1);
119
120         /* the order of the following fields is important */
121
122         /* IEEE80211_RADIOTAP_TSFT */
123         if (status->flag & RX_FLAG_TSFT) {
124                 put_unaligned_le64(status->mactime, pos);
125                 rthdr->it_present |=
126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
127                 pos += 8;
128         }
129
130         /* IEEE80211_RADIOTAP_FLAGS */
131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
135         if (status->flag & RX_FLAG_SHORTPRE)
136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
137         pos++;
138
139         /* IEEE80211_RADIOTAP_RATE */
140         if (status->flag & RX_FLAG_HT) {
141                 /*
142                  * TODO: add following information into radiotap header once
143                  * suitable fields are defined for it:
144                  * - MCS index (status->rate_idx)
145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
147                  */
148                 *pos = 0;
149         } else {
150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
151                 *pos = rate->bitrate / 5;
152         }
153         pos++;
154
155         /* IEEE80211_RADIOTAP_CHANNEL */
156         put_unaligned_le16(status->freq, pos);
157         pos += 2;
158         if (status->band == IEEE80211_BAND_5GHZ)
159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
160                                    pos);
161         else if (status->flag & RX_FLAG_HT)
162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
163                                    pos);
164         else if (rate->flags & IEEE80211_RATE_ERP_G)
165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
166                                    pos);
167         else
168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
169                                    pos);
170         pos += 2;
171
172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
174                 *pos = status->signal;
175                 rthdr->it_present |=
176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
177                 pos++;
178         }
179
180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
181
182         /* IEEE80211_RADIOTAP_ANTENNA */
183         *pos = status->antenna;
184         pos++;
185
186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
187
188         /* IEEE80211_RADIOTAP_RX_FLAGS */
189         /* ensure 2 byte alignment for the 2 byte field as required */
190         if ((pos - (u8 *)rthdr) & 1)
191                 pos++;
192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
194         put_unaligned_le16(rx_flags, pos);
195         pos += 2;
196 }
197
198 /*
199  * This function copies a received frame to all monitor interfaces and
200  * returns a cleaned-up SKB that no longer includes the FCS nor the
201  * radiotap header the driver might have added.
202  */
203 static struct sk_buff *
204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
205                      struct ieee80211_rate *rate)
206 {
207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
208         struct ieee80211_sub_if_data *sdata;
209         int needed_headroom = 0;
210         struct sk_buff *skb, *skb2;
211         struct net_device *prev_dev = NULL;
212         int present_fcs_len = 0;
213
214         /*
215          * First, we may need to make a copy of the skb because
216          *  (1) we need to modify it for radiotap (if not present), and
217          *  (2) the other RX handlers will modify the skb we got.
218          *
219          * We don't need to, of course, if we aren't going to return
220          * the SKB because it has a bad FCS/PLCP checksum.
221          */
222
223         /* room for the radiotap header based on driver features */
224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
225
226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
227                 present_fcs_len = FCS_LEN;
228
229         /* make sure hdr->frame_control is on the linear part */
230         if (!pskb_may_pull(origskb, 2)) {
231                 dev_kfree_skb(origskb);
232                 return NULL;
233         }
234
235         if (!local->monitors) {
236                 if (should_drop_frame(origskb, present_fcs_len)) {
237                         dev_kfree_skb(origskb);
238                         return NULL;
239                 }
240
241                 return remove_monitor_info(local, origskb);
242         }
243
244         if (should_drop_frame(origskb, present_fcs_len)) {
245                 /* only need to expand headroom if necessary */
246                 skb = origskb;
247                 origskb = NULL;
248
249                 /*
250                  * This shouldn't trigger often because most devices have an
251                  * RX header they pull before we get here, and that should
252                  * be big enough for our radiotap information. We should
253                  * probably export the length to drivers so that we can have
254                  * them allocate enough headroom to start with.
255                  */
256                 if (skb_headroom(skb) < needed_headroom &&
257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
258                         dev_kfree_skb(skb);
259                         return NULL;
260                 }
261         } else {
262                 /*
263                  * Need to make a copy and possibly remove radiotap header
264                  * and FCS from the original.
265                  */
266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
267
268                 origskb = remove_monitor_info(local, origskb);
269
270                 if (!skb)
271                         return origskb;
272         }
273
274         /* prepend radiotap information */
275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
276
277         skb_reset_mac_header(skb);
278         skb->ip_summed = CHECKSUM_UNNECESSARY;
279         skb->pkt_type = PACKET_OTHERHOST;
280         skb->protocol = htons(ETH_P_802_2);
281
282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
284                         continue;
285
286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
287                         continue;
288
289                 if (!ieee80211_sdata_running(sdata))
290                         continue;
291
292                 if (prev_dev) {
293                         skb2 = skb_clone(skb, GFP_ATOMIC);
294                         if (skb2) {
295                                 skb2->dev = prev_dev;
296                                 netif_receive_skb(skb2);
297                         }
298                 }
299
300                 prev_dev = sdata->dev;
301                 sdata->dev->stats.rx_packets++;
302                 sdata->dev->stats.rx_bytes += skb->len;
303         }
304
305         if (prev_dev) {
306                 skb->dev = prev_dev;
307                 netif_receive_skb(skb);
308         } else
309                 dev_kfree_skb(skb);
310
311         return origskb;
312 }
313
314
315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
316 {
317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
318         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
319         int tid;
320
321         /* does the frame have a qos control field? */
322         if (ieee80211_is_data_qos(hdr->frame_control)) {
323                 u8 *qc = ieee80211_get_qos_ctl(hdr);
324                 /* frame has qos control */
325                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
326                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
327                         status->rx_flags |= IEEE80211_RX_AMSDU;
328         } else {
329                 /*
330                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
331                  *
332                  *      Sequence numbers for management frames, QoS data
333                  *      frames with a broadcast/multicast address in the
334                  *      Address 1 field, and all non-QoS data frames sent
335                  *      by QoS STAs are assigned using an additional single
336                  *      modulo-4096 counter, [...]
337                  *
338                  * We also use that counter for non-QoS STAs.
339                  */
340                 tid = NUM_RX_DATA_QUEUES - 1;
341         }
342
343         rx->queue = tid;
344         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
345          * For now, set skb->priority to 0 for other cases. */
346         rx->skb->priority = (tid > 7) ? 0 : tid;
347 }
348
349 /**
350  * DOC: Packet alignment
351  *
352  * Drivers always need to pass packets that are aligned to two-byte boundaries
353  * to the stack.
354  *
355  * Additionally, should, if possible, align the payload data in a way that
356  * guarantees that the contained IP header is aligned to a four-byte
357  * boundary. In the case of regular frames, this simply means aligning the
358  * payload to a four-byte boundary (because either the IP header is directly
359  * contained, or IV/RFC1042 headers that have a length divisible by four are
360  * in front of it).  If the payload data is not properly aligned and the
361  * architecture doesn't support efficient unaligned operations, mac80211
362  * will align the data.
363  *
364  * With A-MSDU frames, however, the payload data address must yield two modulo
365  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
366  * push the IP header further back to a multiple of four again. Thankfully, the
367  * specs were sane enough this time around to require padding each A-MSDU
368  * subframe to a length that is a multiple of four.
369  *
370  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
371  * the payload is not supported, the driver is required to move the 802.11
372  * header to be directly in front of the payload in that case.
373  */
374 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
375 {
376 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
377         WARN_ONCE((unsigned long)rx->skb->data & 1,
378                   "unaligned packet at 0x%p\n", rx->skb->data);
379 #endif
380 }
381
382
383 /* rx handlers */
384
385 static ieee80211_rx_result debug_noinline
386 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
387 {
388         struct ieee80211_local *local = rx->local;
389         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
390         struct sk_buff *skb = rx->skb;
391
392         if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN)))
393                 return RX_CONTINUE;
394
395         if (test_bit(SCAN_HW_SCANNING, &local->scanning))
396                 return ieee80211_scan_rx(rx->sdata, skb);
397
398         if (test_bit(SCAN_SW_SCANNING, &local->scanning)) {
399                 /* drop all the other packets during a software scan anyway */
400                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
401                         dev_kfree_skb(skb);
402                 return RX_QUEUED;
403         }
404
405         /* scanning finished during invoking of handlers */
406         I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
407         return RX_DROP_UNUSABLE;
408 }
409
410
411 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
412 {
413         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
414
415         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
416                 return 0;
417
418         return ieee80211_is_robust_mgmt_frame(hdr);
419 }
420
421
422 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
423 {
424         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
425
426         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
427                 return 0;
428
429         return ieee80211_is_robust_mgmt_frame(hdr);
430 }
431
432
433 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
434 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
435 {
436         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
437         struct ieee80211_mmie *mmie;
438
439         if (skb->len < 24 + sizeof(*mmie) ||
440             !is_multicast_ether_addr(hdr->da))
441                 return -1;
442
443         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
444                 return -1; /* not a robust management frame */
445
446         mmie = (struct ieee80211_mmie *)
447                 (skb->data + skb->len - sizeof(*mmie));
448         if (mmie->element_id != WLAN_EID_MMIE ||
449             mmie->length != sizeof(*mmie) - 2)
450                 return -1;
451
452         return le16_to_cpu(mmie->key_id);
453 }
454
455
456 static ieee80211_rx_result
457 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
458 {
459         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
460         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
461         char *dev_addr = rx->sdata->vif.addr;
462
463         if (ieee80211_is_data(hdr->frame_control)) {
464                 if (is_multicast_ether_addr(hdr->addr1)) {
465                         if (ieee80211_has_tods(hdr->frame_control) ||
466                                 !ieee80211_has_fromds(hdr->frame_control))
467                                 return RX_DROP_MONITOR;
468                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
469                                 return RX_DROP_MONITOR;
470                 } else {
471                         if (!ieee80211_has_a4(hdr->frame_control))
472                                 return RX_DROP_MONITOR;
473                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
474                                 return RX_DROP_MONITOR;
475                 }
476         }
477
478         /* If there is not an established peer link and this is not a peer link
479          * establisment frame, beacon or probe, drop the frame.
480          */
481
482         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
483                 struct ieee80211_mgmt *mgmt;
484
485                 if (!ieee80211_is_mgmt(hdr->frame_control))
486                         return RX_DROP_MONITOR;
487
488                 if (ieee80211_is_action(hdr->frame_control)) {
489                         mgmt = (struct ieee80211_mgmt *)hdr;
490                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
491                                 return RX_DROP_MONITOR;
492                         return RX_CONTINUE;
493                 }
494
495                 if (ieee80211_is_probe_req(hdr->frame_control) ||
496                     ieee80211_is_probe_resp(hdr->frame_control) ||
497                     ieee80211_is_beacon(hdr->frame_control))
498                         return RX_CONTINUE;
499
500                 return RX_DROP_MONITOR;
501
502         }
503
504 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
505
506         if (ieee80211_is_data(hdr->frame_control) &&
507             is_multicast_ether_addr(hdr->addr1) &&
508             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
509                 return RX_DROP_MONITOR;
510 #undef msh_h_get
511
512         return RX_CONTINUE;
513 }
514
515 #define SEQ_MODULO 0x1000
516 #define SEQ_MASK   0xfff
517
518 static inline int seq_less(u16 sq1, u16 sq2)
519 {
520         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
521 }
522
523 static inline u16 seq_inc(u16 sq)
524 {
525         return (sq + 1) & SEQ_MASK;
526 }
527
528 static inline u16 seq_sub(u16 sq1, u16 sq2)
529 {
530         return (sq1 - sq2) & SEQ_MASK;
531 }
532
533
534 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
535                                             struct tid_ampdu_rx *tid_agg_rx,
536                                             int index,
537                                             struct sk_buff_head *frames)
538 {
539         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
540
541         if (!skb)
542                 goto no_frame;
543
544         /* release the frame from the reorder ring buffer */
545         tid_agg_rx->stored_mpdu_num--;
546         tid_agg_rx->reorder_buf[index] = NULL;
547         __skb_queue_tail(frames, skb);
548
549 no_frame:
550         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
551 }
552
553 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
554                                              struct tid_ampdu_rx *tid_agg_rx,
555                                              u16 head_seq_num,
556                                              struct sk_buff_head *frames)
557 {
558         int index;
559
560         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
561                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
562                                                         tid_agg_rx->buf_size;
563                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
564         }
565 }
566
567 /*
568  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
569  * the skb was added to the buffer longer than this time ago, the earlier
570  * frames that have not yet been received are assumed to be lost and the skb
571  * can be released for processing. This may also release other skb's from the
572  * reorder buffer if there are no additional gaps between the frames.
573  *
574  * Callers must hold tid_agg_rx->reorder_lock.
575  */
576 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
577
578 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
579                                           struct tid_ampdu_rx *tid_agg_rx,
580                                           struct sk_buff_head *frames)
581 {
582         int index, j;
583
584         /* release the buffer until next missing frame */
585         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
586                                                 tid_agg_rx->buf_size;
587         if (!tid_agg_rx->reorder_buf[index] &&
588             tid_agg_rx->stored_mpdu_num > 1) {
589                 /*
590                  * No buffers ready to be released, but check whether any
591                  * frames in the reorder buffer have timed out.
592                  */
593                 int skipped = 1;
594                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
595                      j = (j + 1) % tid_agg_rx->buf_size) {
596                         if (!tid_agg_rx->reorder_buf[j]) {
597                                 skipped++;
598                                 continue;
599                         }
600                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
601                                         HT_RX_REORDER_BUF_TIMEOUT))
602                                 goto set_release_timer;
603
604 #ifdef CONFIG_MAC80211_HT_DEBUG
605                         if (net_ratelimit())
606                                 wiphy_debug(hw->wiphy,
607                                             "release an RX reorder frame due to timeout on earlier frames\n");
608 #endif
609                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
610                                                         j, frames);
611
612                         /*
613                          * Increment the head seq# also for the skipped slots.
614                          */
615                         tid_agg_rx->head_seq_num =
616                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
617                         skipped = 0;
618                 }
619         } else while (tid_agg_rx->reorder_buf[index]) {
620                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
621                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
622                                                         tid_agg_rx->buf_size;
623         }
624
625         /*
626          * Disable the reorder release timer for now.
627          *
628          * The current implementation lacks a proper locking scheme
629          * which would protect vital statistic and debug counters
630          * from being updated by two different but concurrent BHs.
631          *
632          * More information about the topic is available from:
633          * - thread: http://marc.info/?t=128635927000001
634          *
635          * What was wrong:
636          * =>  http://marc.info/?l=linux-wireless&m=128636170811964
637          * "Basically the thing is that until your patch, the data
638          *  in the struct didn't actually need locking because it
639          *  was accessed by the RX path only which is not concurrent."
640          *
641          * List of what needs to be fixed:
642          * => http://marc.info/?l=linux-wireless&m=128656352920957
643          *
644
645         if (tid_agg_rx->stored_mpdu_num) {
646                 j = index = seq_sub(tid_agg_rx->head_seq_num,
647                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
648
649                 for (; j != (index - 1) % tid_agg_rx->buf_size;
650                      j = (j + 1) % tid_agg_rx->buf_size) {
651                         if (tid_agg_rx->reorder_buf[j])
652                                 break;
653                 }
654
655  set_release_timer:
656
657                 mod_timer(&tid_agg_rx->reorder_timer,
658                           tid_agg_rx->reorder_time[j] +
659                           HT_RX_REORDER_BUF_TIMEOUT);
660         } else {
661                 del_timer(&tid_agg_rx->reorder_timer);
662         }
663         */
664
665 set_release_timer:
666         return;
667 }
668
669 /*
670  * As this function belongs to the RX path it must be under
671  * rcu_read_lock protection. It returns false if the frame
672  * can be processed immediately, true if it was consumed.
673  */
674 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
675                                              struct tid_ampdu_rx *tid_agg_rx,
676                                              struct sk_buff *skb,
677                                              struct sk_buff_head *frames)
678 {
679         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
680         u16 sc = le16_to_cpu(hdr->seq_ctrl);
681         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
682         u16 head_seq_num, buf_size;
683         int index;
684         bool ret = true;
685
686         buf_size = tid_agg_rx->buf_size;
687         head_seq_num = tid_agg_rx->head_seq_num;
688
689         spin_lock(&tid_agg_rx->reorder_lock);
690         /* frame with out of date sequence number */
691         if (seq_less(mpdu_seq_num, head_seq_num)) {
692                 dev_kfree_skb(skb);
693                 goto out;
694         }
695
696         /*
697          * If frame the sequence number exceeds our buffering window
698          * size release some previous frames to make room for this one.
699          */
700         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
701                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
702                 /* release stored frames up to new head to stack */
703                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
704                                                  frames);
705         }
706
707         /* Now the new frame is always in the range of the reordering buffer */
708
709         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
710
711         /* check if we already stored this frame */
712         if (tid_agg_rx->reorder_buf[index]) {
713                 dev_kfree_skb(skb);
714                 goto out;
715         }
716
717         /*
718          * If the current MPDU is in the right order and nothing else
719          * is stored we can process it directly, no need to buffer it.
720          */
721         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
722             tid_agg_rx->stored_mpdu_num == 0) {
723                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
724                 ret = false;
725                 goto out;
726         }
727
728         /* put the frame in the reordering buffer */
729         tid_agg_rx->reorder_buf[index] = skb;
730         tid_agg_rx->reorder_time[index] = jiffies;
731         tid_agg_rx->stored_mpdu_num++;
732         ieee80211_sta_reorder_release(hw, tid_agg_rx, frames);
733
734  out:
735         spin_unlock(&tid_agg_rx->reorder_lock);
736         return ret;
737 }
738
739 /*
740  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
741  * true if the MPDU was buffered, false if it should be processed.
742  */
743 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
744                                        struct sk_buff_head *frames)
745 {
746         struct sk_buff *skb = rx->skb;
747         struct ieee80211_local *local = rx->local;
748         struct ieee80211_hw *hw = &local->hw;
749         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
750         struct sta_info *sta = rx->sta;
751         struct tid_ampdu_rx *tid_agg_rx;
752         u16 sc;
753         int tid;
754
755         if (!ieee80211_is_data_qos(hdr->frame_control))
756                 goto dont_reorder;
757
758         /*
759          * filter the QoS data rx stream according to
760          * STA/TID and check if this STA/TID is on aggregation
761          */
762
763         if (!sta)
764                 goto dont_reorder;
765
766         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
767
768         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
769         if (!tid_agg_rx)
770                 goto dont_reorder;
771
772         /* qos null data frames are excluded */
773         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
774                 goto dont_reorder;
775
776         /* new, potentially un-ordered, ampdu frame - process it */
777
778         /* reset session timer */
779         if (tid_agg_rx->timeout)
780                 mod_timer(&tid_agg_rx->session_timer,
781                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
782
783         /* if this mpdu is fragmented - terminate rx aggregation session */
784         sc = le16_to_cpu(hdr->seq_ctrl);
785         if (sc & IEEE80211_SCTL_FRAG) {
786                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
787                 skb_queue_tail(&rx->sdata->skb_queue, skb);
788                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
789                 return;
790         }
791
792         /*
793          * No locking needed -- we will only ever process one
794          * RX packet at a time, and thus own tid_agg_rx. All
795          * other code manipulating it needs to (and does) make
796          * sure that we cannot get to it any more before doing
797          * anything with it.
798          */
799         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
800                 return;
801
802  dont_reorder:
803         __skb_queue_tail(frames, skb);
804 }
805
806 static ieee80211_rx_result debug_noinline
807 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
808 {
809         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
810         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
811
812         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
813         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
814                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
815                              rx->sta->last_seq_ctrl[rx->queue] ==
816                              hdr->seq_ctrl)) {
817                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
818                                 rx->local->dot11FrameDuplicateCount++;
819                                 rx->sta->num_duplicates++;
820                         }
821                         return RX_DROP_MONITOR;
822                 } else
823                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
824         }
825
826         if (unlikely(rx->skb->len < 16)) {
827                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
828                 return RX_DROP_MONITOR;
829         }
830
831         /* Drop disallowed frame classes based on STA auth/assoc state;
832          * IEEE 802.11, Chap 5.5.
833          *
834          * mac80211 filters only based on association state, i.e. it drops
835          * Class 3 frames from not associated stations. hostapd sends
836          * deauth/disassoc frames when needed. In addition, hostapd is
837          * responsible for filtering on both auth and assoc states.
838          */
839
840         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
841                 return ieee80211_rx_mesh_check(rx);
842
843         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
844                       ieee80211_is_pspoll(hdr->frame_control)) &&
845                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
846                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
847                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
848                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
849                      !ieee80211_has_tods(hdr->frame_control) &&
850                      ieee80211_is_data(hdr->frame_control)) ||
851                     !(status->rx_flags & IEEE80211_RX_RA_MATCH)) {
852                         /* Drop IBSS frames and frames for other hosts
853                          * silently. */
854                         return RX_DROP_MONITOR;
855                 }
856
857                 return RX_DROP_MONITOR;
858         }
859
860         return RX_CONTINUE;
861 }
862
863
864 static ieee80211_rx_result debug_noinline
865 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
866 {
867         struct sk_buff *skb = rx->skb;
868         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
869         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
870         int keyidx;
871         int hdrlen;
872         ieee80211_rx_result result = RX_DROP_UNUSABLE;
873         struct ieee80211_key *sta_ptk = NULL;
874         int mmie_keyidx = -1;
875         __le16 fc;
876
877         /*
878          * Key selection 101
879          *
880          * There are four types of keys:
881          *  - GTK (group keys)
882          *  - IGTK (group keys for management frames)
883          *  - PTK (pairwise keys)
884          *  - STK (station-to-station pairwise keys)
885          *
886          * When selecting a key, we have to distinguish between multicast
887          * (including broadcast) and unicast frames, the latter can only
888          * use PTKs and STKs while the former always use GTKs and IGTKs.
889          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
890          * unicast frames can also use key indices like GTKs. Hence, if we
891          * don't have a PTK/STK we check the key index for a WEP key.
892          *
893          * Note that in a regular BSS, multicast frames are sent by the
894          * AP only, associated stations unicast the frame to the AP first
895          * which then multicasts it on their behalf.
896          *
897          * There is also a slight problem in IBSS mode: GTKs are negotiated
898          * with each station, that is something we don't currently handle.
899          * The spec seems to expect that one negotiates the same key with
900          * every station but there's no such requirement; VLANs could be
901          * possible.
902          */
903
904         /*
905          * No point in finding a key and decrypting if the frame is neither
906          * addressed to us nor a multicast frame.
907          */
908         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
909                 return RX_CONTINUE;
910
911         /* start without a key */
912         rx->key = NULL;
913
914         if (rx->sta)
915                 sta_ptk = rcu_dereference(rx->sta->ptk);
916
917         fc = hdr->frame_control;
918
919         if (!ieee80211_has_protected(fc))
920                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
921
922         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
923                 rx->key = sta_ptk;
924                 if ((status->flag & RX_FLAG_DECRYPTED) &&
925                     (status->flag & RX_FLAG_IV_STRIPPED))
926                         return RX_CONTINUE;
927                 /* Skip decryption if the frame is not protected. */
928                 if (!ieee80211_has_protected(fc))
929                         return RX_CONTINUE;
930         } else if (mmie_keyidx >= 0) {
931                 /* Broadcast/multicast robust management frame / BIP */
932                 if ((status->flag & RX_FLAG_DECRYPTED) &&
933                     (status->flag & RX_FLAG_IV_STRIPPED))
934                         return RX_CONTINUE;
935
936                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
937                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
938                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
939                 if (rx->sta)
940                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
941                 if (!rx->key)
942                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
943         } else if (!ieee80211_has_protected(fc)) {
944                 /*
945                  * The frame was not protected, so skip decryption. However, we
946                  * need to set rx->key if there is a key that could have been
947                  * used so that the frame may be dropped if encryption would
948                  * have been expected.
949                  */
950                 struct ieee80211_key *key = NULL;
951                 if (ieee80211_is_mgmt(fc) &&
952                     is_multicast_ether_addr(hdr->addr1) &&
953                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
954                         rx->key = key;
955                 else if ((key = rcu_dereference(rx->sdata->default_key)))
956                         rx->key = key;
957                 return RX_CONTINUE;
958         } else {
959                 u8 keyid;
960                 /*
961                  * The device doesn't give us the IV so we won't be
962                  * able to look up the key. That's ok though, we
963                  * don't need to decrypt the frame, we just won't
964                  * be able to keep statistics accurate.
965                  * Except for key threshold notifications, should
966                  * we somehow allow the driver to tell us which key
967                  * the hardware used if this flag is set?
968                  */
969                 if ((status->flag & RX_FLAG_DECRYPTED) &&
970                     (status->flag & RX_FLAG_IV_STRIPPED))
971                         return RX_CONTINUE;
972
973                 hdrlen = ieee80211_hdrlen(fc);
974
975                 if (rx->skb->len < 8 + hdrlen)
976                         return RX_DROP_UNUSABLE; /* TODO: count this? */
977
978                 /*
979                  * no need to call ieee80211_wep_get_keyidx,
980                  * it verifies a bunch of things we've done already
981                  */
982                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
983                 keyidx = keyid >> 6;
984
985                 /* check per-station GTK first, if multicast packet */
986                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
987                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
988
989                 /* if not found, try default key */
990                 if (!rx->key) {
991                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
992
993                         /*
994                          * RSNA-protected unicast frames should always be
995                          * sent with pairwise or station-to-station keys,
996                          * but for WEP we allow using a key index as well.
997                          */
998                         if (rx->key &&
999                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1000                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1001                             !is_multicast_ether_addr(hdr->addr1))
1002                                 rx->key = NULL;
1003                 }
1004         }
1005
1006         if (rx->key) {
1007                 rx->key->tx_rx_count++;
1008                 /* TODO: add threshold stuff again */
1009         } else {
1010                 return RX_DROP_MONITOR;
1011         }
1012
1013         if (skb_linearize(rx->skb))
1014                 return RX_DROP_UNUSABLE;
1015         /* the hdr variable is invalid now! */
1016
1017         switch (rx->key->conf.cipher) {
1018         case WLAN_CIPHER_SUITE_WEP40:
1019         case WLAN_CIPHER_SUITE_WEP104:
1020                 /* Check for weak IVs if possible */
1021                 if (rx->sta && ieee80211_is_data(fc) &&
1022                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
1023                      !(status->flag & RX_FLAG_DECRYPTED)) &&
1024                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1025                         rx->sta->wep_weak_iv_count++;
1026
1027                 result = ieee80211_crypto_wep_decrypt(rx);
1028                 break;
1029         case WLAN_CIPHER_SUITE_TKIP:
1030                 result = ieee80211_crypto_tkip_decrypt(rx);
1031                 break;
1032         case WLAN_CIPHER_SUITE_CCMP:
1033                 result = ieee80211_crypto_ccmp_decrypt(rx);
1034                 break;
1035         case WLAN_CIPHER_SUITE_AES_CMAC:
1036                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1037                 break;
1038         default:
1039                 /*
1040                  * We can reach here only with HW-only algorithms
1041                  * but why didn't it decrypt the frame?!
1042                  */
1043                 return RX_DROP_UNUSABLE;
1044         }
1045
1046         /* either the frame has been decrypted or will be dropped */
1047         status->flag |= RX_FLAG_DECRYPTED;
1048
1049         return result;
1050 }
1051
1052 static ieee80211_rx_result debug_noinline
1053 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1054 {
1055         struct ieee80211_local *local;
1056         struct ieee80211_hdr *hdr;
1057         struct sk_buff *skb;
1058
1059         local = rx->local;
1060         skb = rx->skb;
1061         hdr = (struct ieee80211_hdr *) skb->data;
1062
1063         if (!local->pspolling)
1064                 return RX_CONTINUE;
1065
1066         if (!ieee80211_has_fromds(hdr->frame_control))
1067                 /* this is not from AP */
1068                 return RX_CONTINUE;
1069
1070         if (!ieee80211_is_data(hdr->frame_control))
1071                 return RX_CONTINUE;
1072
1073         if (!ieee80211_has_moredata(hdr->frame_control)) {
1074                 /* AP has no more frames buffered for us */
1075                 local->pspolling = false;
1076                 return RX_CONTINUE;
1077         }
1078
1079         /* more data bit is set, let's request a new frame from the AP */
1080         ieee80211_send_pspoll(local, rx->sdata);
1081
1082         return RX_CONTINUE;
1083 }
1084
1085 static void ap_sta_ps_start(struct sta_info *sta)
1086 {
1087         struct ieee80211_sub_if_data *sdata = sta->sdata;
1088         struct ieee80211_local *local = sdata->local;
1089
1090         atomic_inc(&sdata->bss->num_sta_ps);
1091         set_sta_flags(sta, WLAN_STA_PS_STA);
1092         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1093 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1094         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1095                sdata->name, sta->sta.addr, sta->sta.aid);
1096 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1097 }
1098
1099 static void ap_sta_ps_end(struct sta_info *sta)
1100 {
1101         struct ieee80211_sub_if_data *sdata = sta->sdata;
1102
1103         atomic_dec(&sdata->bss->num_sta_ps);
1104
1105         clear_sta_flags(sta, WLAN_STA_PS_STA);
1106
1107 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1108         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1109                sdata->name, sta->sta.addr, sta->sta.aid);
1110 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1111
1112         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1113 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1114                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1115                        sdata->name, sta->sta.addr, sta->sta.aid);
1116 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1117                 return;
1118         }
1119
1120         ieee80211_sta_ps_deliver_wakeup(sta);
1121 }
1122
1123 static ieee80211_rx_result debug_noinline
1124 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1125 {
1126         struct sta_info *sta = rx->sta;
1127         struct sk_buff *skb = rx->skb;
1128         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1129         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1130
1131         if (!sta)
1132                 return RX_CONTINUE;
1133
1134         /*
1135          * Update last_rx only for IBSS packets which are for the current
1136          * BSSID to avoid keeping the current IBSS network alive in cases
1137          * where other STAs start using different BSSID.
1138          */
1139         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1140                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1141                                                 NL80211_IFTYPE_ADHOC);
1142                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1143                         sta->last_rx = jiffies;
1144         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1145                 /*
1146                  * Mesh beacons will update last_rx when if they are found to
1147                  * match the current local configuration when processed.
1148                  */
1149                 sta->last_rx = jiffies;
1150         }
1151
1152         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1153                 return RX_CONTINUE;
1154
1155         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1156                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1157
1158         sta->rx_fragments++;
1159         sta->rx_bytes += rx->skb->len;
1160         sta->last_signal = status->signal;
1161
1162         /*
1163          * Change STA power saving mode only at the end of a frame
1164          * exchange sequence.
1165          */
1166         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1167             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1168              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1169                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1170                         /*
1171                          * Ignore doze->wake transitions that are
1172                          * indicated by non-data frames, the standard
1173                          * is unclear here, but for example going to
1174                          * PS mode and then scanning would cause a
1175                          * doze->wake transition for the probe request,
1176                          * and that is clearly undesirable.
1177                          */
1178                         if (ieee80211_is_data(hdr->frame_control) &&
1179                             !ieee80211_has_pm(hdr->frame_control))
1180                                 ap_sta_ps_end(sta);
1181                 } else {
1182                         if (ieee80211_has_pm(hdr->frame_control))
1183                                 ap_sta_ps_start(sta);
1184                 }
1185         }
1186
1187         /*
1188          * Drop (qos-)data::nullfunc frames silently, since they
1189          * are used only to control station power saving mode.
1190          */
1191         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1192             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1193                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1194
1195                 /*
1196                  * If we receive a 4-addr nullfunc frame from a STA
1197                  * that was not moved to a 4-addr STA vlan yet, drop
1198                  * the frame to the monitor interface, to make sure
1199                  * that hostapd sees it
1200                  */
1201                 if (ieee80211_has_a4(hdr->frame_control) &&
1202                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1203                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1204                       !rx->sdata->u.vlan.sta)))
1205                         return RX_DROP_MONITOR;
1206                 /*
1207                  * Update counter and free packet here to avoid
1208                  * counting this as a dropped packed.
1209                  */
1210                 sta->rx_packets++;
1211                 dev_kfree_skb(rx->skb);
1212                 return RX_QUEUED;
1213         }
1214
1215         return RX_CONTINUE;
1216 } /* ieee80211_rx_h_sta_process */
1217
1218 static inline struct ieee80211_fragment_entry *
1219 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1220                          unsigned int frag, unsigned int seq, int rx_queue,
1221                          struct sk_buff **skb)
1222 {
1223         struct ieee80211_fragment_entry *entry;
1224         int idx;
1225
1226         idx = sdata->fragment_next;
1227         entry = &sdata->fragments[sdata->fragment_next++];
1228         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1229                 sdata->fragment_next = 0;
1230
1231         if (!skb_queue_empty(&entry->skb_list)) {
1232 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1233                 struct ieee80211_hdr *hdr =
1234                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1235                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1236                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1237                        "addr1=%pM addr2=%pM\n",
1238                        sdata->name, idx,
1239                        jiffies - entry->first_frag_time, entry->seq,
1240                        entry->last_frag, hdr->addr1, hdr->addr2);
1241 #endif
1242                 __skb_queue_purge(&entry->skb_list);
1243         }
1244
1245         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1246         *skb = NULL;
1247         entry->first_frag_time = jiffies;
1248         entry->seq = seq;
1249         entry->rx_queue = rx_queue;
1250         entry->last_frag = frag;
1251         entry->ccmp = 0;
1252         entry->extra_len = 0;
1253
1254         return entry;
1255 }
1256
1257 static inline struct ieee80211_fragment_entry *
1258 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1259                           unsigned int frag, unsigned int seq,
1260                           int rx_queue, struct ieee80211_hdr *hdr)
1261 {
1262         struct ieee80211_fragment_entry *entry;
1263         int i, idx;
1264
1265         idx = sdata->fragment_next;
1266         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1267                 struct ieee80211_hdr *f_hdr;
1268
1269                 idx--;
1270                 if (idx < 0)
1271                         idx = IEEE80211_FRAGMENT_MAX - 1;
1272
1273                 entry = &sdata->fragments[idx];
1274                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1275                     entry->rx_queue != rx_queue ||
1276                     entry->last_frag + 1 != frag)
1277                         continue;
1278
1279                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1280
1281                 /*
1282                  * Check ftype and addresses are equal, else check next fragment
1283                  */
1284                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1285                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1286                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1287                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1288                         continue;
1289
1290                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1291                         __skb_queue_purge(&entry->skb_list);
1292                         continue;
1293                 }
1294                 return entry;
1295         }
1296
1297         return NULL;
1298 }
1299
1300 static ieee80211_rx_result debug_noinline
1301 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1302 {
1303         struct ieee80211_hdr *hdr;
1304         u16 sc;
1305         __le16 fc;
1306         unsigned int frag, seq;
1307         struct ieee80211_fragment_entry *entry;
1308         struct sk_buff *skb;
1309         struct ieee80211_rx_status *status;
1310
1311         hdr = (struct ieee80211_hdr *)rx->skb->data;
1312         fc = hdr->frame_control;
1313         sc = le16_to_cpu(hdr->seq_ctrl);
1314         frag = sc & IEEE80211_SCTL_FRAG;
1315
1316         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1317                    (rx->skb)->len < 24 ||
1318                    is_multicast_ether_addr(hdr->addr1))) {
1319                 /* not fragmented */
1320                 goto out;
1321         }
1322         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1323
1324         if (skb_linearize(rx->skb))
1325                 return RX_DROP_UNUSABLE;
1326
1327         /*
1328          *  skb_linearize() might change the skb->data and
1329          *  previously cached variables (in this case, hdr) need to
1330          *  be refreshed with the new data.
1331          */
1332         hdr = (struct ieee80211_hdr *)rx->skb->data;
1333         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1334
1335         if (frag == 0) {
1336                 /* This is the first fragment of a new frame. */
1337                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1338                                                  rx->queue, &(rx->skb));
1339                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1340                     ieee80211_has_protected(fc)) {
1341                         int queue = ieee80211_is_mgmt(fc) ?
1342                                 NUM_RX_DATA_QUEUES : rx->queue;
1343                         /* Store CCMP PN so that we can verify that the next
1344                          * fragment has a sequential PN value. */
1345                         entry->ccmp = 1;
1346                         memcpy(entry->last_pn,
1347                                rx->key->u.ccmp.rx_pn[queue],
1348                                CCMP_PN_LEN);
1349                 }
1350                 return RX_QUEUED;
1351         }
1352
1353         /* This is a fragment for a frame that should already be pending in
1354          * fragment cache. Add this fragment to the end of the pending entry.
1355          */
1356         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1357         if (!entry) {
1358                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1359                 return RX_DROP_MONITOR;
1360         }
1361
1362         /* Verify that MPDUs within one MSDU have sequential PN values.
1363          * (IEEE 802.11i, 8.3.3.4.5) */
1364         if (entry->ccmp) {
1365                 int i;
1366                 u8 pn[CCMP_PN_LEN], *rpn;
1367                 int queue;
1368                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1369                         return RX_DROP_UNUSABLE;
1370                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1371                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1372                         pn[i]++;
1373                         if (pn[i])
1374                                 break;
1375                 }
1376                 queue = ieee80211_is_mgmt(fc) ?
1377                         NUM_RX_DATA_QUEUES : rx->queue;
1378                 rpn = rx->key->u.ccmp.rx_pn[queue];
1379                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1380                         return RX_DROP_UNUSABLE;
1381                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1382         }
1383
1384         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1385         __skb_queue_tail(&entry->skb_list, rx->skb);
1386         entry->last_frag = frag;
1387         entry->extra_len += rx->skb->len;
1388         if (ieee80211_has_morefrags(fc)) {
1389                 rx->skb = NULL;
1390                 return RX_QUEUED;
1391         }
1392
1393         rx->skb = __skb_dequeue(&entry->skb_list);
1394         if (skb_tailroom(rx->skb) < entry->extra_len) {
1395                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1396                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1397                                               GFP_ATOMIC))) {
1398                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1399                         __skb_queue_purge(&entry->skb_list);
1400                         return RX_DROP_UNUSABLE;
1401                 }
1402         }
1403         while ((skb = __skb_dequeue(&entry->skb_list))) {
1404                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1405                 dev_kfree_skb(skb);
1406         }
1407
1408         /* Complete frame has been reassembled - process it now */
1409         status = IEEE80211_SKB_RXCB(rx->skb);
1410         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1411
1412  out:
1413         if (rx->sta)
1414                 rx->sta->rx_packets++;
1415         if (is_multicast_ether_addr(hdr->addr1))
1416                 rx->local->dot11MulticastReceivedFrameCount++;
1417         else
1418                 ieee80211_led_rx(rx->local);
1419         return RX_CONTINUE;
1420 }
1421
1422 static ieee80211_rx_result debug_noinline
1423 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1424 {
1425         struct ieee80211_sub_if_data *sdata = rx->sdata;
1426         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1427         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1428
1429         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1430                    !(status->rx_flags & IEEE80211_RX_RA_MATCH)))
1431                 return RX_CONTINUE;
1432
1433         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1434             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1435                 return RX_DROP_UNUSABLE;
1436
1437         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1438                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1439         else
1440                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1441
1442         /* Free PS Poll skb here instead of returning RX_DROP that would
1443          * count as an dropped frame. */
1444         dev_kfree_skb(rx->skb);
1445
1446         return RX_QUEUED;
1447 }
1448
1449 static ieee80211_rx_result debug_noinline
1450 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1451 {
1452         u8 *data = rx->skb->data;
1453         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1454
1455         if (!ieee80211_is_data_qos(hdr->frame_control))
1456                 return RX_CONTINUE;
1457
1458         /* remove the qos control field, update frame type and meta-data */
1459         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1460                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1461         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1462         /* change frame type to non QOS */
1463         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1464
1465         return RX_CONTINUE;
1466 }
1467
1468 static int
1469 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1470 {
1471         if (unlikely(!rx->sta ||
1472             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1473                 return -EACCES;
1474
1475         return 0;
1476 }
1477
1478 static int
1479 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1480 {
1481         struct sk_buff *skb = rx->skb;
1482         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1483
1484         /*
1485          * Pass through unencrypted frames if the hardware has
1486          * decrypted them already.
1487          */
1488         if (status->flag & RX_FLAG_DECRYPTED)
1489                 return 0;
1490
1491         /* Drop unencrypted frames if key is set. */
1492         if (unlikely(!ieee80211_has_protected(fc) &&
1493                      !ieee80211_is_nullfunc(fc) &&
1494                      ieee80211_is_data(fc) &&
1495                      (rx->key || rx->sdata->drop_unencrypted)))
1496                 return -EACCES;
1497
1498         return 0;
1499 }
1500
1501 static int
1502 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1503 {
1504         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1505         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1506         __le16 fc = hdr->frame_control;
1507
1508         /*
1509          * Pass through unencrypted frames if the hardware has
1510          * decrypted them already.
1511          */
1512         if (status->flag & RX_FLAG_DECRYPTED)
1513                 return 0;
1514
1515         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1516                 if (unlikely(!ieee80211_has_protected(fc) &&
1517                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1518                              rx->key))
1519                         return -EACCES;
1520                 /* BIP does not use Protected field, so need to check MMIE */
1521                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1522                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1523                         return -EACCES;
1524                 /*
1525                  * When using MFP, Action frames are not allowed prior to
1526                  * having configured keys.
1527                  */
1528                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1529                              ieee80211_is_robust_mgmt_frame(
1530                                      (struct ieee80211_hdr *) rx->skb->data)))
1531                         return -EACCES;
1532         }
1533
1534         return 0;
1535 }
1536
1537 static int
1538 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1539 {
1540         struct ieee80211_sub_if_data *sdata = rx->sdata;
1541         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1542
1543         if (ieee80211_has_a4(hdr->frame_control) &&
1544             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1545                 return -1;
1546
1547         if (is_multicast_ether_addr(hdr->addr1) &&
1548             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1549              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1550                 return -1;
1551
1552         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1553 }
1554
1555 /*
1556  * requires that rx->skb is a frame with ethernet header
1557  */
1558 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1559 {
1560         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1561                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1562         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1563
1564         /*
1565          * Allow EAPOL frames to us/the PAE group address regardless
1566          * of whether the frame was encrypted or not.
1567          */
1568         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1569             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1570              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1571                 return true;
1572
1573         if (ieee80211_802_1x_port_control(rx) ||
1574             ieee80211_drop_unencrypted(rx, fc))
1575                 return false;
1576
1577         return true;
1578 }
1579
1580 /*
1581  * requires that rx->skb is a frame with ethernet header
1582  */
1583 static void
1584 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1585 {
1586         struct ieee80211_sub_if_data *sdata = rx->sdata;
1587         struct net_device *dev = sdata->dev;
1588         struct sk_buff *skb, *xmit_skb;
1589         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1590         struct sta_info *dsta;
1591         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1592
1593         skb = rx->skb;
1594         xmit_skb = NULL;
1595
1596         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1597              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1598             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1599             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1600             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1601                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1602                         /*
1603                          * send multicast frames both to higher layers in
1604                          * local net stack and back to the wireless medium
1605                          */
1606                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1607                         if (!xmit_skb && net_ratelimit())
1608                                 printk(KERN_DEBUG "%s: failed to clone "
1609                                        "multicast frame\n", dev->name);
1610                 } else {
1611                         dsta = sta_info_get(sdata, skb->data);
1612                         if (dsta) {
1613                                 /*
1614                                  * The destination station is associated to
1615                                  * this AP (in this VLAN), so send the frame
1616                                  * directly to it and do not pass it to local
1617                                  * net stack.
1618                                  */
1619                                 xmit_skb = skb;
1620                                 skb = NULL;
1621                         }
1622                 }
1623         }
1624
1625         if (skb) {
1626                 int align __maybe_unused;
1627
1628 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1629                 /*
1630                  * 'align' will only take the values 0 or 2 here
1631                  * since all frames are required to be aligned
1632                  * to 2-byte boundaries when being passed to
1633                  * mac80211. That also explains the __skb_push()
1634                  * below.
1635                  */
1636                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1637                 if (align) {
1638                         if (WARN_ON(skb_headroom(skb) < 3)) {
1639                                 dev_kfree_skb(skb);
1640                                 skb = NULL;
1641                         } else {
1642                                 u8 *data = skb->data;
1643                                 size_t len = skb_headlen(skb);
1644                                 skb->data -= align;
1645                                 memmove(skb->data, data, len);
1646                                 skb_set_tail_pointer(skb, len);
1647                         }
1648                 }
1649 #endif
1650
1651                 if (skb) {
1652                         /* deliver to local stack */
1653                         skb->protocol = eth_type_trans(skb, dev);
1654                         memset(skb->cb, 0, sizeof(skb->cb));
1655                         netif_receive_skb(skb);
1656                 }
1657         }
1658
1659         if (xmit_skb) {
1660                 /* send to wireless media */
1661                 xmit_skb->protocol = htons(ETH_P_802_3);
1662                 skb_reset_network_header(xmit_skb);
1663                 skb_reset_mac_header(xmit_skb);
1664                 dev_queue_xmit(xmit_skb);
1665         }
1666 }
1667
1668 static ieee80211_rx_result debug_noinline
1669 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1670 {
1671         struct net_device *dev = rx->sdata->dev;
1672         struct sk_buff *skb = rx->skb;
1673         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1674         __le16 fc = hdr->frame_control;
1675         struct sk_buff_head frame_list;
1676         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1677
1678         if (unlikely(!ieee80211_is_data(fc)))
1679                 return RX_CONTINUE;
1680
1681         if (unlikely(!ieee80211_is_data_present(fc)))
1682                 return RX_DROP_MONITOR;
1683
1684         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1685                 return RX_CONTINUE;
1686
1687         if (ieee80211_has_a4(hdr->frame_control) &&
1688             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1689             !rx->sdata->u.vlan.sta)
1690                 return RX_DROP_UNUSABLE;
1691
1692         if (is_multicast_ether_addr(hdr->addr1) &&
1693             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1694               rx->sdata->u.vlan.sta) ||
1695              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1696               rx->sdata->u.mgd.use_4addr)))
1697                 return RX_DROP_UNUSABLE;
1698
1699         skb->dev = dev;
1700         __skb_queue_head_init(&frame_list);
1701
1702         if (skb_linearize(skb))
1703                 return RX_DROP_UNUSABLE;
1704
1705         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1706                                  rx->sdata->vif.type,
1707                                  rx->local->hw.extra_tx_headroom);
1708
1709         while (!skb_queue_empty(&frame_list)) {
1710                 rx->skb = __skb_dequeue(&frame_list);
1711
1712                 if (!ieee80211_frame_allowed(rx, fc)) {
1713                         dev_kfree_skb(rx->skb);
1714                         continue;
1715                 }
1716                 dev->stats.rx_packets++;
1717                 dev->stats.rx_bytes += rx->skb->len;
1718
1719                 ieee80211_deliver_skb(rx);
1720         }
1721
1722         return RX_QUEUED;
1723 }
1724
1725 #ifdef CONFIG_MAC80211_MESH
1726 static ieee80211_rx_result
1727 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1728 {
1729         struct ieee80211_hdr *hdr;
1730         struct ieee80211s_hdr *mesh_hdr;
1731         unsigned int hdrlen;
1732         struct sk_buff *skb = rx->skb, *fwd_skb;
1733         struct ieee80211_local *local = rx->local;
1734         struct ieee80211_sub_if_data *sdata = rx->sdata;
1735         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1736
1737         hdr = (struct ieee80211_hdr *) skb->data;
1738         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1739         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1740
1741         if (!ieee80211_is_data(hdr->frame_control))
1742                 return RX_CONTINUE;
1743
1744         if (!mesh_hdr->ttl)
1745                 /* illegal frame */
1746                 return RX_DROP_MONITOR;
1747
1748         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1749                 struct mesh_path *mppath;
1750                 char *proxied_addr;
1751                 char *mpp_addr;
1752
1753                 if (is_multicast_ether_addr(hdr->addr1)) {
1754                         mpp_addr = hdr->addr3;
1755                         proxied_addr = mesh_hdr->eaddr1;
1756                 } else {
1757                         mpp_addr = hdr->addr4;
1758                         proxied_addr = mesh_hdr->eaddr2;
1759                 }
1760
1761                 rcu_read_lock();
1762                 mppath = mpp_path_lookup(proxied_addr, sdata);
1763                 if (!mppath) {
1764                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1765                 } else {
1766                         spin_lock_bh(&mppath->state_lock);
1767                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1768                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1769                         spin_unlock_bh(&mppath->state_lock);
1770                 }
1771                 rcu_read_unlock();
1772         }
1773
1774         /* Frame has reached destination.  Don't forward */
1775         if (!is_multicast_ether_addr(hdr->addr1) &&
1776             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1777                 return RX_CONTINUE;
1778
1779         mesh_hdr->ttl--;
1780
1781         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1782                 if (!mesh_hdr->ttl)
1783                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1784                                                      dropped_frames_ttl);
1785                 else {
1786                         struct ieee80211_hdr *fwd_hdr;
1787                         struct ieee80211_tx_info *info;
1788
1789                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1790
1791                         if (!fwd_skb && net_ratelimit())
1792                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1793                                                    sdata->name);
1794
1795                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1796                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1797                         info = IEEE80211_SKB_CB(fwd_skb);
1798                         memset(info, 0, sizeof(*info));
1799                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1800                         info->control.vif = &rx->sdata->vif;
1801                         skb_set_queue_mapping(skb,
1802                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1803                         ieee80211_set_qos_hdr(local, skb);
1804                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1805                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1806                                                                 fwded_mcast);
1807                         else {
1808                                 int err;
1809                                 /*
1810                                  * Save TA to addr1 to send TA a path error if a
1811                                  * suitable next hop is not found
1812                                  */
1813                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1814                                                 ETH_ALEN);
1815                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1816                                 /* Failed to immediately resolve next hop:
1817                                  * fwded frame was dropped or will be added
1818                                  * later to the pending skb queue.  */
1819                                 if (err)
1820                                         return RX_DROP_MONITOR;
1821
1822                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1823                                                                 fwded_unicast);
1824                         }
1825                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1826                                                      fwded_frames);
1827                         ieee80211_add_pending_skb(local, fwd_skb);
1828                 }
1829         }
1830
1831         if (is_multicast_ether_addr(hdr->addr1) ||
1832             sdata->dev->flags & IFF_PROMISC)
1833                 return RX_CONTINUE;
1834         else
1835                 return RX_DROP_MONITOR;
1836 }
1837 #endif
1838
1839 static ieee80211_rx_result debug_noinline
1840 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1841 {
1842         struct ieee80211_sub_if_data *sdata = rx->sdata;
1843         struct ieee80211_local *local = rx->local;
1844         struct net_device *dev = sdata->dev;
1845         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1846         __le16 fc = hdr->frame_control;
1847         int err;
1848
1849         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1850                 return RX_CONTINUE;
1851
1852         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1853                 return RX_DROP_MONITOR;
1854
1855         /*
1856          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1857          * that a 4-addr station can be detected and moved into a separate VLAN
1858          */
1859         if (ieee80211_has_a4(hdr->frame_control) &&
1860             sdata->vif.type == NL80211_IFTYPE_AP)
1861                 return RX_DROP_MONITOR;
1862
1863         err = __ieee80211_data_to_8023(rx);
1864         if (unlikely(err))
1865                 return RX_DROP_UNUSABLE;
1866
1867         if (!ieee80211_frame_allowed(rx, fc))
1868                 return RX_DROP_MONITOR;
1869
1870         rx->skb->dev = dev;
1871
1872         dev->stats.rx_packets++;
1873         dev->stats.rx_bytes += rx->skb->len;
1874
1875         if (ieee80211_is_data(hdr->frame_control) &&
1876             !is_multicast_ether_addr(hdr->addr1) &&
1877             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1878                         mod_timer(&local->dynamic_ps_timer, jiffies +
1879                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1880         }
1881
1882         ieee80211_deliver_skb(rx);
1883
1884         return RX_QUEUED;
1885 }
1886
1887 static ieee80211_rx_result debug_noinline
1888 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1889 {
1890         struct ieee80211_local *local = rx->local;
1891         struct ieee80211_hw *hw = &local->hw;
1892         struct sk_buff *skb = rx->skb;
1893         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1894         struct tid_ampdu_rx *tid_agg_rx;
1895         u16 start_seq_num;
1896         u16 tid;
1897
1898         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1899                 return RX_CONTINUE;
1900
1901         if (ieee80211_is_back_req(bar->frame_control)) {
1902                 struct {
1903                         __le16 control, start_seq_num;
1904                 } __packed bar_data;
1905
1906                 if (!rx->sta)
1907                         return RX_DROP_MONITOR;
1908
1909                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1910                                   &bar_data, sizeof(bar_data)))
1911                         return RX_DROP_MONITOR;
1912
1913                 tid = le16_to_cpu(bar_data.control) >> 12;
1914
1915                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1916                 if (!tid_agg_rx)
1917                         return RX_DROP_MONITOR;
1918
1919                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1920
1921                 /* reset session timer */
1922                 if (tid_agg_rx->timeout)
1923                         mod_timer(&tid_agg_rx->session_timer,
1924                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1925
1926                 /* release stored frames up to start of BAR */
1927                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1928                                                  frames);
1929                 kfree_skb(skb);
1930                 return RX_QUEUED;
1931         }
1932
1933         /*
1934          * After this point, we only want management frames,
1935          * so we can drop all remaining control frames to
1936          * cooked monitor interfaces.
1937          */
1938         return RX_DROP_MONITOR;
1939 }
1940
1941 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1942                                            struct ieee80211_mgmt *mgmt,
1943                                            size_t len)
1944 {
1945         struct ieee80211_local *local = sdata->local;
1946         struct sk_buff *skb;
1947         struct ieee80211_mgmt *resp;
1948
1949         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1950                 /* Not to own unicast address */
1951                 return;
1952         }
1953
1954         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1955             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1956                 /* Not from the current AP or not associated yet. */
1957                 return;
1958         }
1959
1960         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1961                 /* Too short SA Query request frame */
1962                 return;
1963         }
1964
1965         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1966         if (skb == NULL)
1967                 return;
1968
1969         skb_reserve(skb, local->hw.extra_tx_headroom);
1970         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1971         memset(resp, 0, 24);
1972         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1973         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1974         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1975         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1976                                           IEEE80211_STYPE_ACTION);
1977         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1978         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1979         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1980         memcpy(resp->u.action.u.sa_query.trans_id,
1981                mgmt->u.action.u.sa_query.trans_id,
1982                WLAN_SA_QUERY_TR_ID_LEN);
1983
1984         ieee80211_tx_skb(sdata, skb);
1985 }
1986
1987 static ieee80211_rx_result debug_noinline
1988 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
1989 {
1990         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1991         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1992
1993         /*
1994          * From here on, look only at management frames.
1995          * Data and control frames are already handled,
1996          * and unknown (reserved) frames are useless.
1997          */
1998         if (rx->skb->len < 24)
1999                 return RX_DROP_MONITOR;
2000
2001         if (!ieee80211_is_mgmt(mgmt->frame_control))
2002                 return RX_DROP_MONITOR;
2003
2004         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2005                 return RX_DROP_MONITOR;
2006
2007         if (ieee80211_drop_unencrypted_mgmt(rx))
2008                 return RX_DROP_UNUSABLE;
2009
2010         return RX_CONTINUE;
2011 }
2012
2013 static ieee80211_rx_result debug_noinline
2014 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2015 {
2016         struct ieee80211_local *local = rx->local;
2017         struct ieee80211_sub_if_data *sdata = rx->sdata;
2018         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2019         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2020         int len = rx->skb->len;
2021
2022         if (!ieee80211_is_action(mgmt->frame_control))
2023                 return RX_CONTINUE;
2024
2025         /* drop too small frames */
2026         if (len < IEEE80211_MIN_ACTION_SIZE)
2027                 return RX_DROP_UNUSABLE;
2028
2029         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2030                 return RX_DROP_UNUSABLE;
2031
2032         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2033                 return RX_DROP_UNUSABLE;
2034
2035         switch (mgmt->u.action.category) {
2036         case WLAN_CATEGORY_BACK:
2037                 /*
2038                  * The aggregation code is not prepared to handle
2039                  * anything but STA/AP due to the BSSID handling;
2040                  * IBSS could work in the code but isn't supported
2041                  * by drivers or the standard.
2042                  */
2043                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2044                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2045                     sdata->vif.type != NL80211_IFTYPE_AP)
2046                         break;
2047
2048                 /* verify action_code is present */
2049                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2050                         break;
2051
2052                 switch (mgmt->u.action.u.addba_req.action_code) {
2053                 case WLAN_ACTION_ADDBA_REQ:
2054                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2055                                    sizeof(mgmt->u.action.u.addba_req)))
2056                                 goto invalid;
2057                         break;
2058                 case WLAN_ACTION_ADDBA_RESP:
2059                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2060                                    sizeof(mgmt->u.action.u.addba_resp)))
2061                                 goto invalid;
2062                         break;
2063                 case WLAN_ACTION_DELBA:
2064                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2065                                    sizeof(mgmt->u.action.u.delba)))
2066                                 goto invalid;
2067                         break;
2068                 default:
2069                         goto invalid;
2070                 }
2071
2072                 goto queue;
2073         case WLAN_CATEGORY_SPECTRUM_MGMT:
2074                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2075                         break;
2076
2077                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2078                         break;
2079
2080                 /* verify action_code is present */
2081                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2082                         break;
2083
2084                 switch (mgmt->u.action.u.measurement.action_code) {
2085                 case WLAN_ACTION_SPCT_MSR_REQ:
2086                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2087                                    sizeof(mgmt->u.action.u.measurement)))
2088                                 break;
2089                         ieee80211_process_measurement_req(sdata, mgmt, len);
2090                         goto handled;
2091                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2092                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2093                                    sizeof(mgmt->u.action.u.chan_switch)))
2094                                 break;
2095
2096                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2097                                 break;
2098
2099                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2100                                 break;
2101
2102                         goto queue;
2103                 }
2104                 break;
2105         case WLAN_CATEGORY_SA_QUERY:
2106                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2107                            sizeof(mgmt->u.action.u.sa_query)))
2108                         break;
2109
2110                 switch (mgmt->u.action.u.sa_query.action) {
2111                 case WLAN_ACTION_SA_QUERY_REQUEST:
2112                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2113                                 break;
2114                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2115                         goto handled;
2116                 }
2117                 break;
2118         case WLAN_CATEGORY_MESH_PLINK:
2119         case WLAN_CATEGORY_MESH_PATH_SEL:
2120                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2121                         break;
2122                 goto queue;
2123         }
2124
2125         return RX_CONTINUE;
2126
2127  invalid:
2128         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2129         /* will return in the next handlers */
2130         return RX_CONTINUE;
2131
2132  handled:
2133         if (rx->sta)
2134                 rx->sta->rx_packets++;
2135         dev_kfree_skb(rx->skb);
2136         return RX_QUEUED;
2137
2138  queue:
2139         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2140         skb_queue_tail(&sdata->skb_queue, rx->skb);
2141         ieee80211_queue_work(&local->hw, &sdata->work);
2142         if (rx->sta)
2143                 rx->sta->rx_packets++;
2144         return RX_QUEUED;
2145 }
2146
2147 static ieee80211_rx_result debug_noinline
2148 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2149 {
2150         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2151
2152         /* skip known-bad action frames and return them in the next handler */
2153         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2154                 return RX_CONTINUE;
2155
2156         /*
2157          * Getting here means the kernel doesn't know how to handle
2158          * it, but maybe userspace does ... include returned frames
2159          * so userspace can register for those to know whether ones
2160          * it transmitted were processed or returned.
2161          */
2162
2163         if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2164                              rx->skb->data, rx->skb->len,
2165                              GFP_ATOMIC)) {
2166                 if (rx->sta)
2167                         rx->sta->rx_packets++;
2168                 dev_kfree_skb(rx->skb);
2169                 return RX_QUEUED;
2170         }
2171
2172
2173         return RX_CONTINUE;
2174 }
2175
2176 static ieee80211_rx_result debug_noinline
2177 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2178 {
2179         struct ieee80211_local *local = rx->local;
2180         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2181         struct sk_buff *nskb;
2182         struct ieee80211_sub_if_data *sdata = rx->sdata;
2183         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2184
2185         if (!ieee80211_is_action(mgmt->frame_control))
2186                 return RX_CONTINUE;
2187
2188         /*
2189          * For AP mode, hostapd is responsible for handling any action
2190          * frames that we didn't handle, including returning unknown
2191          * ones. For all other modes we will return them to the sender,
2192          * setting the 0x80 bit in the action category, as required by
2193          * 802.11-2007 7.3.1.11.
2194          * Newer versions of hostapd shall also use the management frame
2195          * registration mechanisms, but older ones still use cooked
2196          * monitor interfaces so push all frames there.
2197          */
2198         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2199             (sdata->vif.type == NL80211_IFTYPE_AP ||
2200              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2201                 return RX_DROP_MONITOR;
2202
2203         /* do not return rejected action frames */
2204         if (mgmt->u.action.category & 0x80)
2205                 return RX_DROP_UNUSABLE;
2206
2207         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2208                                GFP_ATOMIC);
2209         if (nskb) {
2210                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2211
2212                 nmgmt->u.action.category |= 0x80;
2213                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2214                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2215
2216                 memset(nskb->cb, 0, sizeof(nskb->cb));
2217
2218                 ieee80211_tx_skb(rx->sdata, nskb);
2219         }
2220         dev_kfree_skb(rx->skb);
2221         return RX_QUEUED;
2222 }
2223
2224 static ieee80211_rx_result debug_noinline
2225 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2226 {
2227         struct ieee80211_sub_if_data *sdata = rx->sdata;
2228         ieee80211_rx_result rxs;
2229         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2230         __le16 stype;
2231
2232         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2233         if (rxs != RX_CONTINUE)
2234                 return rxs;
2235
2236         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2237
2238         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2239             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2240             sdata->vif.type != NL80211_IFTYPE_STATION)
2241                 return RX_DROP_MONITOR;
2242
2243         switch (stype) {
2244         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2245         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2246                 /* process for all: mesh, mlme, ibss */
2247                 break;
2248         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2249         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2250                 /* process only for station */
2251                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2252                         return RX_DROP_MONITOR;
2253                 break;
2254         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2255         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2256                 /* process only for ibss */
2257                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2258                         return RX_DROP_MONITOR;
2259                 break;
2260         default:
2261                 return RX_DROP_MONITOR;
2262         }
2263
2264         /* queue up frame and kick off work to process it */
2265         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2266         skb_queue_tail(&sdata->skb_queue, rx->skb);
2267         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2268         if (rx->sta)
2269                 rx->sta->rx_packets++;
2270
2271         return RX_QUEUED;
2272 }
2273
2274 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2275                                             struct ieee80211_rx_data *rx)
2276 {
2277         int keyidx;
2278         unsigned int hdrlen;
2279
2280         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2281         if (rx->skb->len >= hdrlen + 4)
2282                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2283         else
2284                 keyidx = -1;
2285
2286         if (!rx->sta) {
2287                 /*
2288                  * Some hardware seem to generate incorrect Michael MIC
2289                  * reports; ignore them to avoid triggering countermeasures.
2290                  */
2291                 return;
2292         }
2293
2294         if (!ieee80211_has_protected(hdr->frame_control))
2295                 return;
2296
2297         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2298                 /*
2299                  * APs with pairwise keys should never receive Michael MIC
2300                  * errors for non-zero keyidx because these are reserved for
2301                  * group keys and only the AP is sending real multicast
2302                  * frames in the BSS.
2303                  */
2304                 return;
2305         }
2306
2307         if (!ieee80211_is_data(hdr->frame_control) &&
2308             !ieee80211_is_auth(hdr->frame_control))
2309                 return;
2310
2311         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2312                                         GFP_ATOMIC);
2313 }
2314
2315 /* TODO: use IEEE80211_RX_FRAGMENTED */
2316 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2317                                         struct ieee80211_rate *rate)
2318 {
2319         struct ieee80211_sub_if_data *sdata;
2320         struct ieee80211_local *local = rx->local;
2321         struct ieee80211_rtap_hdr {
2322                 struct ieee80211_radiotap_header hdr;
2323                 u8 flags;
2324                 u8 rate_or_pad;
2325                 __le16 chan_freq;
2326                 __le16 chan_flags;
2327         } __packed *rthdr;
2328         struct sk_buff *skb = rx->skb, *skb2;
2329         struct net_device *prev_dev = NULL;
2330         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2331
2332         /*
2333          * If cooked monitor has been processed already, then
2334          * don't do it again. If not, set the flag.
2335          */
2336         if (rx->flags & IEEE80211_RX_CMNTR)
2337                 goto out_free_skb;
2338         rx->flags |= IEEE80211_RX_CMNTR;
2339
2340         if (skb_headroom(skb) < sizeof(*rthdr) &&
2341             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2342                 goto out_free_skb;
2343
2344         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2345         memset(rthdr, 0, sizeof(*rthdr));
2346         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2347         rthdr->hdr.it_present =
2348                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2349                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2350
2351         if (rate) {
2352                 rthdr->rate_or_pad = rate->bitrate / 5;
2353                 rthdr->hdr.it_present |=
2354                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2355         }
2356         rthdr->chan_freq = cpu_to_le16(status->freq);
2357
2358         if (status->band == IEEE80211_BAND_5GHZ)
2359                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2360                                                 IEEE80211_CHAN_5GHZ);
2361         else
2362                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2363                                                 IEEE80211_CHAN_2GHZ);
2364
2365         skb_set_mac_header(skb, 0);
2366         skb->ip_summed = CHECKSUM_UNNECESSARY;
2367         skb->pkt_type = PACKET_OTHERHOST;
2368         skb->protocol = htons(ETH_P_802_2);
2369
2370         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2371                 if (!ieee80211_sdata_running(sdata))
2372                         continue;
2373
2374                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2375                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2376                         continue;
2377
2378                 if (prev_dev) {
2379                         skb2 = skb_clone(skb, GFP_ATOMIC);
2380                         if (skb2) {
2381                                 skb2->dev = prev_dev;
2382                                 netif_receive_skb(skb2);
2383                         }
2384                 }
2385
2386                 prev_dev = sdata->dev;
2387                 sdata->dev->stats.rx_packets++;
2388                 sdata->dev->stats.rx_bytes += skb->len;
2389         }
2390
2391         if (prev_dev) {
2392                 skb->dev = prev_dev;
2393                 netif_receive_skb(skb);
2394                 return;
2395         }
2396
2397  out_free_skb:
2398         dev_kfree_skb(skb);
2399 }
2400
2401 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2402                                          ieee80211_rx_result res)
2403 {
2404         switch (res) {
2405         case RX_DROP_MONITOR:
2406                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2407                 if (rx->sta)
2408                         rx->sta->rx_dropped++;
2409                 /* fall through */
2410         case RX_CONTINUE: {
2411                 struct ieee80211_rate *rate = NULL;
2412                 struct ieee80211_supported_band *sband;
2413                 struct ieee80211_rx_status *status;
2414
2415                 status = IEEE80211_SKB_RXCB((rx->skb));
2416
2417                 sband = rx->local->hw.wiphy->bands[status->band];
2418                 if (!(status->flag & RX_FLAG_HT))
2419                         rate = &sband->bitrates[status->rate_idx];
2420
2421                 ieee80211_rx_cooked_monitor(rx, rate);
2422                 break;
2423                 }
2424         case RX_DROP_UNUSABLE:
2425                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2426                 if (rx->sta)
2427                         rx->sta->rx_dropped++;
2428                 dev_kfree_skb(rx->skb);
2429                 break;
2430         case RX_QUEUED:
2431                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2432                 break;
2433         }
2434 }
2435
2436 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2437                                   struct sk_buff_head *frames)
2438 {
2439         ieee80211_rx_result res = RX_DROP_MONITOR;
2440         struct sk_buff *skb;
2441
2442 #define CALL_RXH(rxh)                   \
2443         do {                            \
2444                 res = rxh(rx);          \
2445                 if (res != RX_CONTINUE) \
2446                         goto rxh_next;  \
2447         } while (0);
2448
2449         while ((skb = __skb_dequeue(frames))) {
2450                 /*
2451                  * all the other fields are valid across frames
2452                  * that belong to an aMPDU since they are on the
2453                  * same TID from the same station
2454                  */
2455                 rx->skb = skb;
2456                 rx->flags = 0;
2457
2458                 CALL_RXH(ieee80211_rx_h_decrypt)
2459                 CALL_RXH(ieee80211_rx_h_check_more_data)
2460                 CALL_RXH(ieee80211_rx_h_sta_process)
2461                 CALL_RXH(ieee80211_rx_h_defragment)
2462                 CALL_RXH(ieee80211_rx_h_ps_poll)
2463                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2464                 /* must be after MMIC verify so header is counted in MPDU mic */
2465                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2466                 CALL_RXH(ieee80211_rx_h_amsdu)
2467 #ifdef CONFIG_MAC80211_MESH
2468                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2469                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2470 #endif
2471                 CALL_RXH(ieee80211_rx_h_data)
2472
2473                 /* special treatment -- needs the queue */
2474                 res = ieee80211_rx_h_ctrl(rx, frames);
2475                 if (res != RX_CONTINUE)
2476                         goto rxh_next;
2477
2478                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2479                 CALL_RXH(ieee80211_rx_h_action)
2480                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2481                 CALL_RXH(ieee80211_rx_h_action_return)
2482                 CALL_RXH(ieee80211_rx_h_mgmt)
2483
2484  rxh_next:
2485                 ieee80211_rx_handlers_result(rx, res);
2486
2487 #undef CALL_RXH
2488         }
2489 }
2490
2491 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2492 {
2493         struct sk_buff_head reorder_release;
2494         ieee80211_rx_result res = RX_DROP_MONITOR;
2495
2496         __skb_queue_head_init(&reorder_release);
2497
2498 #define CALL_RXH(rxh)                   \
2499         do {                            \
2500                 res = rxh(rx);          \
2501                 if (res != RX_CONTINUE) \
2502                         goto rxh_next;  \
2503         } while (0);
2504
2505         CALL_RXH(ieee80211_rx_h_passive_scan)
2506         CALL_RXH(ieee80211_rx_h_check)
2507
2508         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2509
2510         ieee80211_rx_handlers(rx, &reorder_release);
2511         return;
2512
2513  rxh_next:
2514         ieee80211_rx_handlers_result(rx, res);
2515
2516 #undef CALL_RXH
2517 }
2518
2519 /*
2520  * This function makes calls into the RX path. Therefore the
2521  * caller must hold the sta_info->lock and everything has to
2522  * be under rcu_read_lock protection as well.
2523  */
2524 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2525 {
2526         struct sk_buff_head frames;
2527         struct ieee80211_rx_data rx = {
2528                 .sta = sta,
2529                 .sdata = sta->sdata,
2530                 .local = sta->local,
2531                 .queue = tid,
2532         };
2533         struct tid_ampdu_rx *tid_agg_rx;
2534
2535         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2536         if (!tid_agg_rx)
2537                 return;
2538
2539         __skb_queue_head_init(&frames);
2540
2541         spin_lock(&tid_agg_rx->reorder_lock);
2542         ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx, &frames);
2543         spin_unlock(&tid_agg_rx->reorder_lock);
2544
2545         ieee80211_rx_handlers(&rx, &frames);
2546 }
2547
2548 /* main receive path */
2549
2550 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2551                                 struct ieee80211_hdr *hdr)
2552 {
2553         struct ieee80211_sub_if_data *sdata = rx->sdata;
2554         struct sk_buff *skb = rx->skb;
2555         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2556         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2557         int multicast = is_multicast_ether_addr(hdr->addr1);
2558
2559         switch (sdata->vif.type) {
2560         case NL80211_IFTYPE_STATION:
2561                 if (!bssid && !sdata->u.mgd.use_4addr)
2562                         return 0;
2563                 if (!multicast &&
2564                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2565                         if (!(sdata->dev->flags & IFF_PROMISC))
2566                                 return 0;
2567                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2568                 }
2569                 break;
2570         case NL80211_IFTYPE_ADHOC:
2571                 if (!bssid)
2572                         return 0;
2573                 if (ieee80211_is_beacon(hdr->frame_control)) {
2574                         return 1;
2575                 }
2576                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2577                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2578                                 return 0;
2579                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2580                 } else if (!multicast &&
2581                            compare_ether_addr(sdata->vif.addr,
2582                                               hdr->addr1) != 0) {
2583                         if (!(sdata->dev->flags & IFF_PROMISC))
2584                                 return 0;
2585                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2586                 } else if (!rx->sta) {
2587                         int rate_idx;
2588                         if (status->flag & RX_FLAG_HT)
2589                                 rate_idx = 0; /* TODO: HT rates */
2590                         else
2591                                 rate_idx = status->rate_idx;
2592                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2593                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2594                 }
2595                 break;
2596         case NL80211_IFTYPE_MESH_POINT:
2597                 if (!multicast &&
2598                     compare_ether_addr(sdata->vif.addr,
2599                                        hdr->addr1) != 0) {
2600                         if (!(sdata->dev->flags & IFF_PROMISC))
2601                                 return 0;
2602
2603                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2604                 }
2605                 break;
2606         case NL80211_IFTYPE_AP_VLAN:
2607         case NL80211_IFTYPE_AP:
2608                 if (!bssid) {
2609                         if (compare_ether_addr(sdata->vif.addr,
2610                                                hdr->addr1))
2611                                 return 0;
2612                 } else if (!ieee80211_bssid_match(bssid,
2613                                         sdata->vif.addr)) {
2614                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2615                                 return 0;
2616                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2617                 }
2618                 break;
2619         case NL80211_IFTYPE_WDS:
2620                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2621                         return 0;
2622                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2623                         return 0;
2624                 break;
2625         default:
2626                 /* should never get here */
2627                 WARN_ON(1);
2628                 break;
2629         }
2630
2631         return 1;
2632 }
2633
2634 /*
2635  * This function returns whether or not the SKB
2636  * was destined for RX processing or not, which,
2637  * if consume is true, is equivalent to whether
2638  * or not the skb was consumed.
2639  */
2640 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2641                                             struct sk_buff *skb, bool consume)
2642 {
2643         struct ieee80211_local *local = rx->local;
2644         struct ieee80211_sub_if_data *sdata = rx->sdata;
2645         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2646         struct ieee80211_hdr *hdr = (void *)skb->data;
2647         int prepares;
2648
2649         rx->skb = skb;
2650         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2651         prepares = prepare_for_handlers(rx, hdr);
2652
2653         if (!prepares)
2654                 return false;
2655
2656         if (status->flag & RX_FLAG_MMIC_ERROR) {
2657                 if (status->rx_flags & IEEE80211_RX_RA_MATCH)
2658                         ieee80211_rx_michael_mic_report(hdr, rx);
2659                 return false;
2660         }
2661
2662         if (!consume) {
2663                 skb = skb_copy(skb, GFP_ATOMIC);
2664                 if (!skb) {
2665                         if (net_ratelimit())
2666                                 wiphy_debug(local->hw.wiphy,
2667                                         "failed to copy multicast frame for %s\n",
2668                                         sdata->name);
2669                         return true;
2670                 }
2671
2672                 rx->skb = skb;
2673         }
2674
2675         ieee80211_invoke_rx_handlers(rx);
2676         return true;
2677 }
2678
2679 /*
2680  * This is the actual Rx frames handler. as it blongs to Rx path it must
2681  * be called with rcu_read_lock protection.
2682  */
2683 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2684                                          struct sk_buff *skb)
2685 {
2686         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2687         struct ieee80211_local *local = hw_to_local(hw);
2688         struct ieee80211_sub_if_data *sdata;
2689         struct ieee80211_hdr *hdr;
2690         __le16 fc;
2691         struct ieee80211_rx_data rx;
2692         struct ieee80211_sub_if_data *prev;
2693         struct sta_info *sta, *tmp, *prev_sta;
2694         int err = 0;
2695
2696         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2697         memset(&rx, 0, sizeof(rx));
2698         rx.skb = skb;
2699         rx.local = local;
2700
2701         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2702                 local->dot11ReceivedFragmentCount++;
2703
2704         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2705                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2706                 status->rx_flags |= IEEE80211_RX_IN_SCAN;
2707
2708         if (ieee80211_is_mgmt(fc))
2709                 err = skb_linearize(skb);
2710         else
2711                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2712
2713         if (err) {
2714                 dev_kfree_skb(skb);
2715                 return;
2716         }
2717
2718         hdr = (struct ieee80211_hdr *)skb->data;
2719         ieee80211_parse_qos(&rx);
2720         ieee80211_verify_alignment(&rx);
2721
2722         if (ieee80211_is_data(fc)) {
2723                 prev_sta = NULL;
2724
2725                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2726                         if (!prev_sta) {
2727                                 prev_sta = sta;
2728                                 continue;
2729                         }
2730
2731                         rx.sta = prev_sta;
2732                         rx.sdata = prev_sta->sdata;
2733                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2734
2735                         prev_sta = sta;
2736                 }
2737
2738                 if (prev_sta) {
2739                         rx.sta = prev_sta;
2740                         rx.sdata = prev_sta->sdata;
2741
2742                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2743                                 return;
2744                 }
2745         }
2746
2747         prev = NULL;
2748
2749         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2750                 if (!ieee80211_sdata_running(sdata))
2751                         continue;
2752
2753                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2754                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2755                         continue;
2756
2757                 /*
2758                  * frame is destined for this interface, but if it's
2759                  * not also for the previous one we handle that after
2760                  * the loop to avoid copying the SKB once too much
2761                  */
2762
2763                 if (!prev) {
2764                         prev = sdata;
2765                         continue;
2766                 }
2767
2768                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2769                 rx.sdata = prev;
2770                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2771
2772                 prev = sdata;
2773         }
2774
2775         if (prev) {
2776                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2777                 rx.sdata = prev;
2778
2779                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2780                         return;
2781         }
2782
2783         dev_kfree_skb(skb);
2784 }
2785
2786 /*
2787  * This is the receive path handler. It is called by a low level driver when an
2788  * 802.11 MPDU is received from the hardware.
2789  */
2790 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2791 {
2792         struct ieee80211_local *local = hw_to_local(hw);
2793         struct ieee80211_rate *rate = NULL;
2794         struct ieee80211_supported_band *sband;
2795         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2796
2797         WARN_ON_ONCE(softirq_count() == 0);
2798
2799         if (WARN_ON(status->band < 0 ||
2800                     status->band >= IEEE80211_NUM_BANDS))
2801                 goto drop;
2802
2803         sband = local->hw.wiphy->bands[status->band];
2804         if (WARN_ON(!sband))
2805                 goto drop;
2806
2807         /*
2808          * If we're suspending, it is possible although not too likely
2809          * that we'd be receiving frames after having already partially
2810          * quiesced the stack. We can't process such frames then since
2811          * that might, for example, cause stations to be added or other
2812          * driver callbacks be invoked.
2813          */
2814         if (unlikely(local->quiescing || local->suspended))
2815                 goto drop;
2816
2817         /*
2818          * The same happens when we're not even started,
2819          * but that's worth a warning.
2820          */
2821         if (WARN_ON(!local->started))
2822                 goto drop;
2823
2824         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2825                 /*
2826                  * Validate the rate, unless a PLCP error means that
2827                  * we probably can't have a valid rate here anyway.
2828                  */
2829
2830                 if (status->flag & RX_FLAG_HT) {
2831                         /*
2832                          * rate_idx is MCS index, which can be [0-76]
2833                          * as documented on:
2834                          *
2835                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2836                          *
2837                          * Anything else would be some sort of driver or
2838                          * hardware error. The driver should catch hardware
2839                          * errors.
2840                          */
2841                         if (WARN((status->rate_idx < 0 ||
2842                                  status->rate_idx > 76),
2843                                  "Rate marked as an HT rate but passed "
2844                                  "status->rate_idx is not "
2845                                  "an MCS index [0-76]: %d (0x%02x)\n",
2846                                  status->rate_idx,
2847                                  status->rate_idx))
2848                                 goto drop;
2849                 } else {
2850                         if (WARN_ON(status->rate_idx < 0 ||
2851                                     status->rate_idx >= sband->n_bitrates))
2852                                 goto drop;
2853                         rate = &sband->bitrates[status->rate_idx];
2854                 }
2855         }
2856
2857         status->rx_flags = 0;
2858
2859         /*
2860          * key references and virtual interfaces are protected using RCU
2861          * and this requires that we are in a read-side RCU section during
2862          * receive processing
2863          */
2864         rcu_read_lock();
2865
2866         /*
2867          * Frames with failed FCS/PLCP checksum are not returned,
2868          * all other frames are returned without radiotap header
2869          * if it was previously present.
2870          * Also, frames with less than 16 bytes are dropped.
2871          */
2872         skb = ieee80211_rx_monitor(local, skb, rate);
2873         if (!skb) {
2874                 rcu_read_unlock();
2875                 return;
2876         }
2877
2878         __ieee80211_rx_handle_packet(hw, skb);
2879
2880         rcu_read_unlock();
2881
2882         return;
2883  drop:
2884         kfree_skb(skb);
2885 }
2886 EXPORT_SYMBOL(ieee80211_rx);
2887
2888 /* This is a version of the rx handler that can be called from hard irq
2889  * context. Post the skb on the queue and schedule the tasklet */
2890 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2891 {
2892         struct ieee80211_local *local = hw_to_local(hw);
2893
2894         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2895
2896         skb->pkt_type = IEEE80211_RX_MSG;
2897         skb_queue_tail(&local->skb_queue, skb);
2898         tasklet_schedule(&local->tasklet);
2899 }
2900 EXPORT_SYMBOL(ieee80211_rx_irqsafe);