4fdbed58ca2fcedd2ff18c9518b9e318f987a857
[linux-2.6.git] / net / mac80211 / rx.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/jiffies.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/skbuff.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rcupdate.h>
19 #include <net/mac80211.h>
20 #include <net/ieee80211_radiotap.h>
21
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "led.h"
25 #include "mesh.h"
26 #include "wep.h"
27 #include "wpa.h"
28 #include "tkip.h"
29 #include "wme.h"
30
31 /*
32  * monitor mode reception
33  *
34  * This function cleans up the SKB, i.e. it removes all the stuff
35  * only useful for monitoring.
36  */
37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
38                                            struct sk_buff *skb)
39 {
40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
41                 if (likely(skb->len > FCS_LEN))
42                         __pskb_trim(skb, skb->len - FCS_LEN);
43                 else {
44                         /* driver bug */
45                         WARN_ON(1);
46                         dev_kfree_skb(skb);
47                         skb = NULL;
48                 }
49         }
50
51         return skb;
52 }
53
54 static inline int should_drop_frame(struct sk_buff *skb,
55                                     int present_fcs_len)
56 {
57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
59
60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
61                 return 1;
62         if (unlikely(skb->len < 16 + present_fcs_len))
63                 return 1;
64         if (ieee80211_is_ctl(hdr->frame_control) &&
65             !ieee80211_is_pspoll(hdr->frame_control) &&
66             !ieee80211_is_back_req(hdr->frame_control))
67                 return 1;
68         return 0;
69 }
70
71 static int
72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
73                           struct ieee80211_rx_status *status)
74 {
75         int len;
76
77         /* always present fields */
78         len = sizeof(struct ieee80211_radiotap_header) + 9;
79
80         if (status->flag & RX_FLAG_TSFT)
81                 len += 8;
82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
83                 len += 1;
84
85         if (len & 1) /* padding for RX_FLAGS if necessary */
86                 len++;
87
88         return len;
89 }
90
91 /*
92  * ieee80211_add_rx_radiotap_header - add radiotap header
93  *
94  * add a radiotap header containing all the fields which the hardware provided.
95  */
96 static void
97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
98                                  struct sk_buff *skb,
99                                  struct ieee80211_rate *rate,
100                                  int rtap_len)
101 {
102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
103         struct ieee80211_radiotap_header *rthdr;
104         unsigned char *pos;
105         u16 rx_flags = 0;
106
107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
108         memset(rthdr, 0, rtap_len);
109
110         /* radiotap header, set always present flags */
111         rthdr->it_present =
112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
116         rthdr->it_len = cpu_to_le16(rtap_len);
117
118         pos = (unsigned char *)(rthdr+1);
119
120         /* the order of the following fields is important */
121
122         /* IEEE80211_RADIOTAP_TSFT */
123         if (status->flag & RX_FLAG_TSFT) {
124                 put_unaligned_le64(status->mactime, pos);
125                 rthdr->it_present |=
126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
127                 pos += 8;
128         }
129
130         /* IEEE80211_RADIOTAP_FLAGS */
131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
135         if (status->flag & RX_FLAG_SHORTPRE)
136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
137         pos++;
138
139         /* IEEE80211_RADIOTAP_RATE */
140         if (status->flag & RX_FLAG_HT) {
141                 /*
142                  * TODO: add following information into radiotap header once
143                  * suitable fields are defined for it:
144                  * - MCS index (status->rate_idx)
145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
147                  */
148                 *pos = 0;
149         } else {
150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
151                 *pos = rate->bitrate / 5;
152         }
153         pos++;
154
155         /* IEEE80211_RADIOTAP_CHANNEL */
156         put_unaligned_le16(status->freq, pos);
157         pos += 2;
158         if (status->band == IEEE80211_BAND_5GHZ)
159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
160                                    pos);
161         else if (status->flag & RX_FLAG_HT)
162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
163                                    pos);
164         else if (rate->flags & IEEE80211_RATE_ERP_G)
165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
166                                    pos);
167         else
168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
169                                    pos);
170         pos += 2;
171
172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
174                 *pos = status->signal;
175                 rthdr->it_present |=
176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
177                 pos++;
178         }
179
180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
181
182         /* IEEE80211_RADIOTAP_ANTENNA */
183         *pos = status->antenna;
184         pos++;
185
186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
187
188         /* IEEE80211_RADIOTAP_RX_FLAGS */
189         /* ensure 2 byte alignment for the 2 byte field as required */
190         if ((pos - (u8 *)rthdr) & 1)
191                 pos++;
192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
194         put_unaligned_le16(rx_flags, pos);
195         pos += 2;
196 }
197
198 /*
199  * This function copies a received frame to all monitor interfaces and
200  * returns a cleaned-up SKB that no longer includes the FCS nor the
201  * radiotap header the driver might have added.
202  */
203 static struct sk_buff *
204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
205                      struct ieee80211_rate *rate)
206 {
207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
208         struct ieee80211_sub_if_data *sdata;
209         int needed_headroom = 0;
210         struct sk_buff *skb, *skb2;
211         struct net_device *prev_dev = NULL;
212         int present_fcs_len = 0;
213
214         /*
215          * First, we may need to make a copy of the skb because
216          *  (1) we need to modify it for radiotap (if not present), and
217          *  (2) the other RX handlers will modify the skb we got.
218          *
219          * We don't need to, of course, if we aren't going to return
220          * the SKB because it has a bad FCS/PLCP checksum.
221          */
222
223         /* room for the radiotap header based on driver features */
224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
225
226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
227                 present_fcs_len = FCS_LEN;
228
229         /* make sure hdr->frame_control is on the linear part */
230         if (!pskb_may_pull(origskb, 2)) {
231                 dev_kfree_skb(origskb);
232                 return NULL;
233         }
234
235         if (!local->monitors) {
236                 if (should_drop_frame(origskb, present_fcs_len)) {
237                         dev_kfree_skb(origskb);
238                         return NULL;
239                 }
240
241                 return remove_monitor_info(local, origskb);
242         }
243
244         if (should_drop_frame(origskb, present_fcs_len)) {
245                 /* only need to expand headroom if necessary */
246                 skb = origskb;
247                 origskb = NULL;
248
249                 /*
250                  * This shouldn't trigger often because most devices have an
251                  * RX header they pull before we get here, and that should
252                  * be big enough for our radiotap information. We should
253                  * probably export the length to drivers so that we can have
254                  * them allocate enough headroom to start with.
255                  */
256                 if (skb_headroom(skb) < needed_headroom &&
257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
258                         dev_kfree_skb(skb);
259                         return NULL;
260                 }
261         } else {
262                 /*
263                  * Need to make a copy and possibly remove radiotap header
264                  * and FCS from the original.
265                  */
266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
267
268                 origskb = remove_monitor_info(local, origskb);
269
270                 if (!skb)
271                         return origskb;
272         }
273
274         /* prepend radiotap information */
275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
276
277         skb_reset_mac_header(skb);
278         skb->ip_summed = CHECKSUM_UNNECESSARY;
279         skb->pkt_type = PACKET_OTHERHOST;
280         skb->protocol = htons(ETH_P_802_2);
281
282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
284                         continue;
285
286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
287                         continue;
288
289                 if (!ieee80211_sdata_running(sdata))
290                         continue;
291
292                 if (prev_dev) {
293                         skb2 = skb_clone(skb, GFP_ATOMIC);
294                         if (skb2) {
295                                 skb2->dev = prev_dev;
296                                 netif_receive_skb(skb2);
297                         }
298                 }
299
300                 prev_dev = sdata->dev;
301                 sdata->dev->stats.rx_packets++;
302                 sdata->dev->stats.rx_bytes += skb->len;
303         }
304
305         if (prev_dev) {
306                 skb->dev = prev_dev;
307                 netif_receive_skb(skb);
308         } else
309                 dev_kfree_skb(skb);
310
311         return origskb;
312 }
313
314
315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
316 {
317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
318         int tid;
319
320         /* does the frame have a qos control field? */
321         if (ieee80211_is_data_qos(hdr->frame_control)) {
322                 u8 *qc = ieee80211_get_qos_ctl(hdr);
323                 /* frame has qos control */
324                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
325                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
326                         rx->flags |= IEEE80211_RX_AMSDU;
327                 else
328                         rx->flags &= ~IEEE80211_RX_AMSDU;
329         } else {
330                 /*
331                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
332                  *
333                  *      Sequence numbers for management frames, QoS data
334                  *      frames with a broadcast/multicast address in the
335                  *      Address 1 field, and all non-QoS data frames sent
336                  *      by QoS STAs are assigned using an additional single
337                  *      modulo-4096 counter, [...]
338                  *
339                  * We also use that counter for non-QoS STAs.
340                  */
341                 tid = NUM_RX_DATA_QUEUES - 1;
342         }
343
344         rx->queue = tid;
345         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
346          * For now, set skb->priority to 0 for other cases. */
347         rx->skb->priority = (tid > 7) ? 0 : tid;
348 }
349
350 /**
351  * DOC: Packet alignment
352  *
353  * Drivers always need to pass packets that are aligned to two-byte boundaries
354  * to the stack.
355  *
356  * Additionally, should, if possible, align the payload data in a way that
357  * guarantees that the contained IP header is aligned to a four-byte
358  * boundary. In the case of regular frames, this simply means aligning the
359  * payload to a four-byte boundary (because either the IP header is directly
360  * contained, or IV/RFC1042 headers that have a length divisible by four are
361  * in front of it).  If the payload data is not properly aligned and the
362  * architecture doesn't support efficient unaligned operations, mac80211
363  * will align the data.
364  *
365  * With A-MSDU frames, however, the payload data address must yield two modulo
366  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
367  * push the IP header further back to a multiple of four again. Thankfully, the
368  * specs were sane enough this time around to require padding each A-MSDU
369  * subframe to a length that is a multiple of four.
370  *
371  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
372  * the payload is not supported, the driver is required to move the 802.11
373  * header to be directly in front of the payload in that case.
374  */
375 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
376 {
377 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
378         WARN_ONCE((unsigned long)rx->skb->data & 1,
379                   "unaligned packet at 0x%p\n", rx->skb->data);
380 #endif
381 }
382
383
384 /* rx handlers */
385
386 static ieee80211_rx_result debug_noinline
387 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
388 {
389         struct ieee80211_local *local = rx->local;
390         struct sk_buff *skb = rx->skb;
391
392         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
393                 return ieee80211_scan_rx(rx->sdata, skb);
394
395         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
396                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
397                 /* drop all the other packets during a software scan anyway */
398                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
399                         dev_kfree_skb(skb);
400                 return RX_QUEUED;
401         }
402
403         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
404                 /* scanning finished during invoking of handlers */
405                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
406                 return RX_DROP_UNUSABLE;
407         }
408
409         return RX_CONTINUE;
410 }
411
412
413 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
414 {
415         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
416
417         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
418                 return 0;
419
420         return ieee80211_is_robust_mgmt_frame(hdr);
421 }
422
423
424 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
425 {
426         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
427
428         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
429                 return 0;
430
431         return ieee80211_is_robust_mgmt_frame(hdr);
432 }
433
434
435 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
436 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
437 {
438         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
439         struct ieee80211_mmie *mmie;
440
441         if (skb->len < 24 + sizeof(*mmie) ||
442             !is_multicast_ether_addr(hdr->da))
443                 return -1;
444
445         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
446                 return -1; /* not a robust management frame */
447
448         mmie = (struct ieee80211_mmie *)
449                 (skb->data + skb->len - sizeof(*mmie));
450         if (mmie->element_id != WLAN_EID_MMIE ||
451             mmie->length != sizeof(*mmie) - 2)
452                 return -1;
453
454         return le16_to_cpu(mmie->key_id);
455 }
456
457
458 static ieee80211_rx_result
459 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
460 {
461         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
462         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
463         char *dev_addr = rx->sdata->vif.addr;
464
465         if (ieee80211_is_data(hdr->frame_control)) {
466                 if (is_multicast_ether_addr(hdr->addr1)) {
467                         if (ieee80211_has_tods(hdr->frame_control) ||
468                                 !ieee80211_has_fromds(hdr->frame_control))
469                                 return RX_DROP_MONITOR;
470                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
471                                 return RX_DROP_MONITOR;
472                 } else {
473                         if (!ieee80211_has_a4(hdr->frame_control))
474                                 return RX_DROP_MONITOR;
475                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
476                                 return RX_DROP_MONITOR;
477                 }
478         }
479
480         /* If there is not an established peer link and this is not a peer link
481          * establisment frame, beacon or probe, drop the frame.
482          */
483
484         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
485                 struct ieee80211_mgmt *mgmt;
486
487                 if (!ieee80211_is_mgmt(hdr->frame_control))
488                         return RX_DROP_MONITOR;
489
490                 if (ieee80211_is_action(hdr->frame_control)) {
491                         mgmt = (struct ieee80211_mgmt *)hdr;
492                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
493                                 return RX_DROP_MONITOR;
494                         return RX_CONTINUE;
495                 }
496
497                 if (ieee80211_is_probe_req(hdr->frame_control) ||
498                     ieee80211_is_probe_resp(hdr->frame_control) ||
499                     ieee80211_is_beacon(hdr->frame_control))
500                         return RX_CONTINUE;
501
502                 return RX_DROP_MONITOR;
503
504         }
505
506 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
507
508         if (ieee80211_is_data(hdr->frame_control) &&
509             is_multicast_ether_addr(hdr->addr1) &&
510             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
511                 return RX_DROP_MONITOR;
512 #undef msh_h_get
513
514         return RX_CONTINUE;
515 }
516
517 #define SEQ_MODULO 0x1000
518 #define SEQ_MASK   0xfff
519
520 static inline int seq_less(u16 sq1, u16 sq2)
521 {
522         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
523 }
524
525 static inline u16 seq_inc(u16 sq)
526 {
527         return (sq + 1) & SEQ_MASK;
528 }
529
530 static inline u16 seq_sub(u16 sq1, u16 sq2)
531 {
532         return (sq1 - sq2) & SEQ_MASK;
533 }
534
535
536 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
537                                             struct tid_ampdu_rx *tid_agg_rx,
538                                             int index,
539                                             struct sk_buff_head *frames)
540 {
541         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
542
543         if (!skb)
544                 goto no_frame;
545
546         /* release the frame from the reorder ring buffer */
547         tid_agg_rx->stored_mpdu_num--;
548         tid_agg_rx->reorder_buf[index] = NULL;
549         __skb_queue_tail(frames, skb);
550
551 no_frame:
552         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
553 }
554
555 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
556                                              struct tid_ampdu_rx *tid_agg_rx,
557                                              u16 head_seq_num,
558                                              struct sk_buff_head *frames)
559 {
560         int index;
561
562         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
563                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
564                                                         tid_agg_rx->buf_size;
565                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
566         }
567 }
568
569 /*
570  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
571  * the skb was added to the buffer longer than this time ago, the earlier
572  * frames that have not yet been received are assumed to be lost and the skb
573  * can be released for processing. This may also release other skb's from the
574  * reorder buffer if there are no additional gaps between the frames.
575  *
576  * Callers must hold tid_agg_rx->reorder_lock.
577  */
578 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
579
580 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
581                                           struct tid_ampdu_rx *tid_agg_rx,
582                                           struct sk_buff_head *frames)
583 {
584         int index, j;
585
586         /* release the buffer until next missing frame */
587         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
588                                                 tid_agg_rx->buf_size;
589         if (!tid_agg_rx->reorder_buf[index] &&
590             tid_agg_rx->stored_mpdu_num > 1) {
591                 /*
592                  * No buffers ready to be released, but check whether any
593                  * frames in the reorder buffer have timed out.
594                  */
595                 int skipped = 1;
596                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
597                      j = (j + 1) % tid_agg_rx->buf_size) {
598                         if (!tid_agg_rx->reorder_buf[j]) {
599                                 skipped++;
600                                 continue;
601                         }
602                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
603                                         HT_RX_REORDER_BUF_TIMEOUT))
604                                 goto set_release_timer;
605
606 #ifdef CONFIG_MAC80211_HT_DEBUG
607                         if (net_ratelimit())
608                                 printk(KERN_DEBUG "%s: release an RX reorder "
609                                        "frame due to timeout on earlier "
610                                        "frames\n",
611                                        wiphy_name(hw->wiphy));
612 #endif
613                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
614                                                         j, frames);
615
616                         /*
617                          * Increment the head seq# also for the skipped slots.
618                          */
619                         tid_agg_rx->head_seq_num =
620                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
621                         skipped = 0;
622                 }
623         } else while (tid_agg_rx->reorder_buf[index]) {
624                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
625                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
626                                                         tid_agg_rx->buf_size;
627         }
628
629         if (tid_agg_rx->stored_mpdu_num) {
630                 j = index = seq_sub(tid_agg_rx->head_seq_num,
631                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
632
633                 for (; j != (index - 1) % tid_agg_rx->buf_size;
634                      j = (j + 1) % tid_agg_rx->buf_size) {
635                         if (tid_agg_rx->reorder_buf[j])
636                                 break;
637                 }
638
639  set_release_timer:
640
641                 mod_timer(&tid_agg_rx->reorder_timer,
642                           tid_agg_rx->reorder_time[j] +
643                           HT_RX_REORDER_BUF_TIMEOUT);
644         } else {
645                 del_timer(&tid_agg_rx->reorder_timer);
646         }
647 }
648
649 /*
650  * As this function belongs to the RX path it must be under
651  * rcu_read_lock protection. It returns false if the frame
652  * can be processed immediately, true if it was consumed.
653  */
654 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
655                                              struct tid_ampdu_rx *tid_agg_rx,
656                                              struct sk_buff *skb,
657                                              struct sk_buff_head *frames)
658 {
659         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
660         u16 sc = le16_to_cpu(hdr->seq_ctrl);
661         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
662         u16 head_seq_num, buf_size;
663         int index;
664         bool ret = true;
665
666         buf_size = tid_agg_rx->buf_size;
667         head_seq_num = tid_agg_rx->head_seq_num;
668
669         spin_lock(&tid_agg_rx->reorder_lock);
670         /* frame with out of date sequence number */
671         if (seq_less(mpdu_seq_num, head_seq_num)) {
672                 dev_kfree_skb(skb);
673                 goto out;
674         }
675
676         /*
677          * If frame the sequence number exceeds our buffering window
678          * size release some previous frames to make room for this one.
679          */
680         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
681                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
682                 /* release stored frames up to new head to stack */
683                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
684                                                  frames);
685         }
686
687         /* Now the new frame is always in the range of the reordering buffer */
688
689         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
690
691         /* check if we already stored this frame */
692         if (tid_agg_rx->reorder_buf[index]) {
693                 dev_kfree_skb(skb);
694                 goto out;
695         }
696
697         /*
698          * If the current MPDU is in the right order and nothing else
699          * is stored we can process it directly, no need to buffer it.
700          */
701         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
702             tid_agg_rx->stored_mpdu_num == 0) {
703                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
704                 ret = false;
705                 goto out;
706         }
707
708         /* put the frame in the reordering buffer */
709         tid_agg_rx->reorder_buf[index] = skb;
710         tid_agg_rx->reorder_time[index] = jiffies;
711         tid_agg_rx->stored_mpdu_num++;
712         ieee80211_sta_reorder_release(hw, tid_agg_rx, frames);
713
714  out:
715         spin_unlock(&tid_agg_rx->reorder_lock);
716         return ret;
717 }
718
719 /*
720  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
721  * true if the MPDU was buffered, false if it should be processed.
722  */
723 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
724                                        struct sk_buff_head *frames)
725 {
726         struct sk_buff *skb = rx->skb;
727         struct ieee80211_local *local = rx->local;
728         struct ieee80211_hw *hw = &local->hw;
729         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
730         struct sta_info *sta = rx->sta;
731         struct tid_ampdu_rx *tid_agg_rx;
732         u16 sc;
733         int tid;
734
735         if (!ieee80211_is_data_qos(hdr->frame_control))
736                 goto dont_reorder;
737
738         /*
739          * filter the QoS data rx stream according to
740          * STA/TID and check if this STA/TID is on aggregation
741          */
742
743         if (!sta)
744                 goto dont_reorder;
745
746         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
747
748         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
749         if (!tid_agg_rx)
750                 goto dont_reorder;
751
752         /* qos null data frames are excluded */
753         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
754                 goto dont_reorder;
755
756         /* new, potentially un-ordered, ampdu frame - process it */
757
758         /* reset session timer */
759         if (tid_agg_rx->timeout)
760                 mod_timer(&tid_agg_rx->session_timer,
761                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
762
763         /* if this mpdu is fragmented - terminate rx aggregation session */
764         sc = le16_to_cpu(hdr->seq_ctrl);
765         if (sc & IEEE80211_SCTL_FRAG) {
766                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
767                 skb_queue_tail(&rx->sdata->skb_queue, skb);
768                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
769                 return;
770         }
771
772         /*
773          * No locking needed -- we will only ever process one
774          * RX packet at a time, and thus own tid_agg_rx. All
775          * other code manipulating it needs to (and does) make
776          * sure that we cannot get to it any more before doing
777          * anything with it.
778          */
779         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
780                 return;
781
782  dont_reorder:
783         __skb_queue_tail(frames, skb);
784 }
785
786 static ieee80211_rx_result debug_noinline
787 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
788 {
789         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
790
791         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
792         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
793                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
794                              rx->sta->last_seq_ctrl[rx->queue] ==
795                              hdr->seq_ctrl)) {
796                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
797                                 rx->local->dot11FrameDuplicateCount++;
798                                 rx->sta->num_duplicates++;
799                         }
800                         return RX_DROP_MONITOR;
801                 } else
802                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
803         }
804
805         if (unlikely(rx->skb->len < 16)) {
806                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
807                 return RX_DROP_MONITOR;
808         }
809
810         /* Drop disallowed frame classes based on STA auth/assoc state;
811          * IEEE 802.11, Chap 5.5.
812          *
813          * mac80211 filters only based on association state, i.e. it drops
814          * Class 3 frames from not associated stations. hostapd sends
815          * deauth/disassoc frames when needed. In addition, hostapd is
816          * responsible for filtering on both auth and assoc states.
817          */
818
819         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
820                 return ieee80211_rx_mesh_check(rx);
821
822         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
823                       ieee80211_is_pspoll(hdr->frame_control)) &&
824                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
825                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
826                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
827                      !ieee80211_has_tods(hdr->frame_control) &&
828                      ieee80211_is_data(hdr->frame_control)) ||
829                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
830                         /* Drop IBSS frames and frames for other hosts
831                          * silently. */
832                         return RX_DROP_MONITOR;
833                 }
834
835                 return RX_DROP_MONITOR;
836         }
837
838         return RX_CONTINUE;
839 }
840
841
842 static ieee80211_rx_result debug_noinline
843 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
844 {
845         struct sk_buff *skb = rx->skb;
846         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
847         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
848         int keyidx;
849         int hdrlen;
850         ieee80211_rx_result result = RX_DROP_UNUSABLE;
851         struct ieee80211_key *stakey = NULL;
852         int mmie_keyidx = -1;
853         __le16 fc;
854
855         /*
856          * Key selection 101
857          *
858          * There are four types of keys:
859          *  - GTK (group keys)
860          *  - IGTK (group keys for management frames)
861          *  - PTK (pairwise keys)
862          *  - STK (station-to-station pairwise keys)
863          *
864          * When selecting a key, we have to distinguish between multicast
865          * (including broadcast) and unicast frames, the latter can only
866          * use PTKs and STKs while the former always use GTKs and IGTKs.
867          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
868          * unicast frames can also use key indices like GTKs. Hence, if we
869          * don't have a PTK/STK we check the key index for a WEP key.
870          *
871          * Note that in a regular BSS, multicast frames are sent by the
872          * AP only, associated stations unicast the frame to the AP first
873          * which then multicasts it on their behalf.
874          *
875          * There is also a slight problem in IBSS mode: GTKs are negotiated
876          * with each station, that is something we don't currently handle.
877          * The spec seems to expect that one negotiates the same key with
878          * every station but there's no such requirement; VLANs could be
879          * possible.
880          */
881
882         /*
883          * No point in finding a key and decrypting if the frame is neither
884          * addressed to us nor a multicast frame.
885          */
886         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
887                 return RX_CONTINUE;
888
889         /* start without a key */
890         rx->key = NULL;
891
892         if (rx->sta)
893                 stakey = rcu_dereference(rx->sta->key);
894
895         fc = hdr->frame_control;
896
897         if (!ieee80211_has_protected(fc))
898                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
899
900         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
901                 rx->key = stakey;
902                 if ((status->flag & RX_FLAG_DECRYPTED) &&
903                     (status->flag & RX_FLAG_IV_STRIPPED))
904                         return RX_CONTINUE;
905                 /* Skip decryption if the frame is not protected. */
906                 if (!ieee80211_has_protected(fc))
907                         return RX_CONTINUE;
908         } else if (mmie_keyidx >= 0) {
909                 /* Broadcast/multicast robust management frame / BIP */
910                 if ((status->flag & RX_FLAG_DECRYPTED) &&
911                     (status->flag & RX_FLAG_IV_STRIPPED))
912                         return RX_CONTINUE;
913
914                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
915                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
916                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
917                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
918         } else if (!ieee80211_has_protected(fc)) {
919                 /*
920                  * The frame was not protected, so skip decryption. However, we
921                  * need to set rx->key if there is a key that could have been
922                  * used so that the frame may be dropped if encryption would
923                  * have been expected.
924                  */
925                 struct ieee80211_key *key = NULL;
926                 if (ieee80211_is_mgmt(fc) &&
927                     is_multicast_ether_addr(hdr->addr1) &&
928                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
929                         rx->key = key;
930                 else if ((key = rcu_dereference(rx->sdata->default_key)))
931                         rx->key = key;
932                 return RX_CONTINUE;
933         } else {
934                 u8 keyid;
935                 /*
936                  * The device doesn't give us the IV so we won't be
937                  * able to look up the key. That's ok though, we
938                  * don't need to decrypt the frame, we just won't
939                  * be able to keep statistics accurate.
940                  * Except for key threshold notifications, should
941                  * we somehow allow the driver to tell us which key
942                  * the hardware used if this flag is set?
943                  */
944                 if ((status->flag & RX_FLAG_DECRYPTED) &&
945                     (status->flag & RX_FLAG_IV_STRIPPED))
946                         return RX_CONTINUE;
947
948                 hdrlen = ieee80211_hdrlen(fc);
949
950                 if (rx->skb->len < 8 + hdrlen)
951                         return RX_DROP_UNUSABLE; /* TODO: count this? */
952
953                 /*
954                  * no need to call ieee80211_wep_get_keyidx,
955                  * it verifies a bunch of things we've done already
956                  */
957                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
958                 keyidx = keyid >> 6;
959
960                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
961
962                 /*
963                  * RSNA-protected unicast frames should always be sent with
964                  * pairwise or station-to-station keys, but for WEP we allow
965                  * using a key index as well.
966                  */
967                 if (rx->key && rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
968                     rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
969                     !is_multicast_ether_addr(hdr->addr1))
970                         rx->key = NULL;
971         }
972
973         if (rx->key) {
974                 rx->key->tx_rx_count++;
975                 /* TODO: add threshold stuff again */
976         } else {
977                 return RX_DROP_MONITOR;
978         }
979
980         if (skb_linearize(rx->skb))
981                 return RX_DROP_UNUSABLE;
982         /* the hdr variable is invalid now! */
983
984         switch (rx->key->conf.cipher) {
985         case WLAN_CIPHER_SUITE_WEP40:
986         case WLAN_CIPHER_SUITE_WEP104:
987                 /* Check for weak IVs if possible */
988                 if (rx->sta && ieee80211_is_data(fc) &&
989                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
990                      !(status->flag & RX_FLAG_DECRYPTED)) &&
991                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
992                         rx->sta->wep_weak_iv_count++;
993
994                 result = ieee80211_crypto_wep_decrypt(rx);
995                 break;
996         case WLAN_CIPHER_SUITE_TKIP:
997                 result = ieee80211_crypto_tkip_decrypt(rx);
998                 break;
999         case WLAN_CIPHER_SUITE_CCMP:
1000                 result = ieee80211_crypto_ccmp_decrypt(rx);
1001                 break;
1002         case WLAN_CIPHER_SUITE_AES_CMAC:
1003                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1004                 break;
1005         }
1006
1007         /* either the frame has been decrypted or will be dropped */
1008         status->flag |= RX_FLAG_DECRYPTED;
1009
1010         return result;
1011 }
1012
1013 static ieee80211_rx_result debug_noinline
1014 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1015 {
1016         struct ieee80211_local *local;
1017         struct ieee80211_hdr *hdr;
1018         struct sk_buff *skb;
1019
1020         local = rx->local;
1021         skb = rx->skb;
1022         hdr = (struct ieee80211_hdr *) skb->data;
1023
1024         if (!local->pspolling)
1025                 return RX_CONTINUE;
1026
1027         if (!ieee80211_has_fromds(hdr->frame_control))
1028                 /* this is not from AP */
1029                 return RX_CONTINUE;
1030
1031         if (!ieee80211_is_data(hdr->frame_control))
1032                 return RX_CONTINUE;
1033
1034         if (!ieee80211_has_moredata(hdr->frame_control)) {
1035                 /* AP has no more frames buffered for us */
1036                 local->pspolling = false;
1037                 return RX_CONTINUE;
1038         }
1039
1040         /* more data bit is set, let's request a new frame from the AP */
1041         ieee80211_send_pspoll(local, rx->sdata);
1042
1043         return RX_CONTINUE;
1044 }
1045
1046 static void ap_sta_ps_start(struct sta_info *sta)
1047 {
1048         struct ieee80211_sub_if_data *sdata = sta->sdata;
1049         struct ieee80211_local *local = sdata->local;
1050
1051         atomic_inc(&sdata->bss->num_sta_ps);
1052         set_sta_flags(sta, WLAN_STA_PS_STA);
1053         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1054 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1055         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1056                sdata->name, sta->sta.addr, sta->sta.aid);
1057 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1058 }
1059
1060 static void ap_sta_ps_end(struct sta_info *sta)
1061 {
1062         struct ieee80211_sub_if_data *sdata = sta->sdata;
1063
1064         atomic_dec(&sdata->bss->num_sta_ps);
1065
1066         clear_sta_flags(sta, WLAN_STA_PS_STA);
1067
1068 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1069         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1070                sdata->name, sta->sta.addr, sta->sta.aid);
1071 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1072
1073         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1074 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1075                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1076                        sdata->name, sta->sta.addr, sta->sta.aid);
1077 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1078                 return;
1079         }
1080
1081         ieee80211_sta_ps_deliver_wakeup(sta);
1082 }
1083
1084 static ieee80211_rx_result debug_noinline
1085 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1086 {
1087         struct sta_info *sta = rx->sta;
1088         struct sk_buff *skb = rx->skb;
1089         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1090         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1091
1092         if (!sta)
1093                 return RX_CONTINUE;
1094
1095         /*
1096          * Update last_rx only for IBSS packets which are for the current
1097          * BSSID to avoid keeping the current IBSS network alive in cases
1098          * where other STAs start using different BSSID.
1099          */
1100         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1101                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1102                                                 NL80211_IFTYPE_ADHOC);
1103                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1104                         sta->last_rx = jiffies;
1105         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1106                 /*
1107                  * Mesh beacons will update last_rx when if they are found to
1108                  * match the current local configuration when processed.
1109                  */
1110                 sta->last_rx = jiffies;
1111         }
1112
1113         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1114                 return RX_CONTINUE;
1115
1116         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1117                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1118
1119         sta->rx_fragments++;
1120         sta->rx_bytes += rx->skb->len;
1121         sta->last_signal = status->signal;
1122
1123         /*
1124          * Change STA power saving mode only at the end of a frame
1125          * exchange sequence.
1126          */
1127         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1128             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1129              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1130                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1131                         /*
1132                          * Ignore doze->wake transitions that are
1133                          * indicated by non-data frames, the standard
1134                          * is unclear here, but for example going to
1135                          * PS mode and then scanning would cause a
1136                          * doze->wake transition for the probe request,
1137                          * and that is clearly undesirable.
1138                          */
1139                         if (ieee80211_is_data(hdr->frame_control) &&
1140                             !ieee80211_has_pm(hdr->frame_control))
1141                                 ap_sta_ps_end(sta);
1142                 } else {
1143                         if (ieee80211_has_pm(hdr->frame_control))
1144                                 ap_sta_ps_start(sta);
1145                 }
1146         }
1147
1148         /*
1149          * Drop (qos-)data::nullfunc frames silently, since they
1150          * are used only to control station power saving mode.
1151          */
1152         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1153             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1154                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1155
1156                 /*
1157                  * If we receive a 4-addr nullfunc frame from a STA
1158                  * that was not moved to a 4-addr STA vlan yet, drop
1159                  * the frame to the monitor interface, to make sure
1160                  * that hostapd sees it
1161                  */
1162                 if (ieee80211_has_a4(hdr->frame_control) &&
1163                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1164                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1165                       !rx->sdata->u.vlan.sta)))
1166                         return RX_DROP_MONITOR;
1167                 /*
1168                  * Update counter and free packet here to avoid
1169                  * counting this as a dropped packed.
1170                  */
1171                 sta->rx_packets++;
1172                 dev_kfree_skb(rx->skb);
1173                 return RX_QUEUED;
1174         }
1175
1176         return RX_CONTINUE;
1177 } /* ieee80211_rx_h_sta_process */
1178
1179 static inline struct ieee80211_fragment_entry *
1180 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1181                          unsigned int frag, unsigned int seq, int rx_queue,
1182                          struct sk_buff **skb)
1183 {
1184         struct ieee80211_fragment_entry *entry;
1185         int idx;
1186
1187         idx = sdata->fragment_next;
1188         entry = &sdata->fragments[sdata->fragment_next++];
1189         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1190                 sdata->fragment_next = 0;
1191
1192         if (!skb_queue_empty(&entry->skb_list)) {
1193 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1194                 struct ieee80211_hdr *hdr =
1195                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1196                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1197                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1198                        "addr1=%pM addr2=%pM\n",
1199                        sdata->name, idx,
1200                        jiffies - entry->first_frag_time, entry->seq,
1201                        entry->last_frag, hdr->addr1, hdr->addr2);
1202 #endif
1203                 __skb_queue_purge(&entry->skb_list);
1204         }
1205
1206         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1207         *skb = NULL;
1208         entry->first_frag_time = jiffies;
1209         entry->seq = seq;
1210         entry->rx_queue = rx_queue;
1211         entry->last_frag = frag;
1212         entry->ccmp = 0;
1213         entry->extra_len = 0;
1214
1215         return entry;
1216 }
1217
1218 static inline struct ieee80211_fragment_entry *
1219 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1220                           unsigned int frag, unsigned int seq,
1221                           int rx_queue, struct ieee80211_hdr *hdr)
1222 {
1223         struct ieee80211_fragment_entry *entry;
1224         int i, idx;
1225
1226         idx = sdata->fragment_next;
1227         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1228                 struct ieee80211_hdr *f_hdr;
1229
1230                 idx--;
1231                 if (idx < 0)
1232                         idx = IEEE80211_FRAGMENT_MAX - 1;
1233
1234                 entry = &sdata->fragments[idx];
1235                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1236                     entry->rx_queue != rx_queue ||
1237                     entry->last_frag + 1 != frag)
1238                         continue;
1239
1240                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1241
1242                 /*
1243                  * Check ftype and addresses are equal, else check next fragment
1244                  */
1245                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1246                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1247                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1248                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1249                         continue;
1250
1251                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1252                         __skb_queue_purge(&entry->skb_list);
1253                         continue;
1254                 }
1255                 return entry;
1256         }
1257
1258         return NULL;
1259 }
1260
1261 static ieee80211_rx_result debug_noinline
1262 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1263 {
1264         struct ieee80211_hdr *hdr;
1265         u16 sc;
1266         __le16 fc;
1267         unsigned int frag, seq;
1268         struct ieee80211_fragment_entry *entry;
1269         struct sk_buff *skb;
1270
1271         hdr = (struct ieee80211_hdr *)rx->skb->data;
1272         fc = hdr->frame_control;
1273         sc = le16_to_cpu(hdr->seq_ctrl);
1274         frag = sc & IEEE80211_SCTL_FRAG;
1275
1276         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1277                    (rx->skb)->len < 24 ||
1278                    is_multicast_ether_addr(hdr->addr1))) {
1279                 /* not fragmented */
1280                 goto out;
1281         }
1282         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1283
1284         if (skb_linearize(rx->skb))
1285                 return RX_DROP_UNUSABLE;
1286
1287         /*
1288          *  skb_linearize() might change the skb->data and
1289          *  previously cached variables (in this case, hdr) need to
1290          *  be refreshed with the new data.
1291          */
1292         hdr = (struct ieee80211_hdr *)rx->skb->data;
1293         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1294
1295         if (frag == 0) {
1296                 /* This is the first fragment of a new frame. */
1297                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1298                                                  rx->queue, &(rx->skb));
1299                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1300                     ieee80211_has_protected(fc)) {
1301                         int queue = ieee80211_is_mgmt(fc) ?
1302                                 NUM_RX_DATA_QUEUES : rx->queue;
1303                         /* Store CCMP PN so that we can verify that the next
1304                          * fragment has a sequential PN value. */
1305                         entry->ccmp = 1;
1306                         memcpy(entry->last_pn,
1307                                rx->key->u.ccmp.rx_pn[queue],
1308                                CCMP_PN_LEN);
1309                 }
1310                 return RX_QUEUED;
1311         }
1312
1313         /* This is a fragment for a frame that should already be pending in
1314          * fragment cache. Add this fragment to the end of the pending entry.
1315          */
1316         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1317         if (!entry) {
1318                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1319                 return RX_DROP_MONITOR;
1320         }
1321
1322         /* Verify that MPDUs within one MSDU have sequential PN values.
1323          * (IEEE 802.11i, 8.3.3.4.5) */
1324         if (entry->ccmp) {
1325                 int i;
1326                 u8 pn[CCMP_PN_LEN], *rpn;
1327                 int queue;
1328                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1329                         return RX_DROP_UNUSABLE;
1330                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1331                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1332                         pn[i]++;
1333                         if (pn[i])
1334                                 break;
1335                 }
1336                 queue = ieee80211_is_mgmt(fc) ?
1337                         NUM_RX_DATA_QUEUES : rx->queue;
1338                 rpn = rx->key->u.ccmp.rx_pn[queue];
1339                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1340                         return RX_DROP_UNUSABLE;
1341                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1342         }
1343
1344         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1345         __skb_queue_tail(&entry->skb_list, rx->skb);
1346         entry->last_frag = frag;
1347         entry->extra_len += rx->skb->len;
1348         if (ieee80211_has_morefrags(fc)) {
1349                 rx->skb = NULL;
1350                 return RX_QUEUED;
1351         }
1352
1353         rx->skb = __skb_dequeue(&entry->skb_list);
1354         if (skb_tailroom(rx->skb) < entry->extra_len) {
1355                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1356                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1357                                               GFP_ATOMIC))) {
1358                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1359                         __skb_queue_purge(&entry->skb_list);
1360                         return RX_DROP_UNUSABLE;
1361                 }
1362         }
1363         while ((skb = __skb_dequeue(&entry->skb_list))) {
1364                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1365                 dev_kfree_skb(skb);
1366         }
1367
1368         /* Complete frame has been reassembled - process it now */
1369         rx->flags |= IEEE80211_RX_FRAGMENTED;
1370
1371  out:
1372         if (rx->sta)
1373                 rx->sta->rx_packets++;
1374         if (is_multicast_ether_addr(hdr->addr1))
1375                 rx->local->dot11MulticastReceivedFrameCount++;
1376         else
1377                 ieee80211_led_rx(rx->local);
1378         return RX_CONTINUE;
1379 }
1380
1381 static ieee80211_rx_result debug_noinline
1382 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1383 {
1384         struct ieee80211_sub_if_data *sdata = rx->sdata;
1385         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1386
1387         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1388                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1389                 return RX_CONTINUE;
1390
1391         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1392             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1393                 return RX_DROP_UNUSABLE;
1394
1395         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1396                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1397         else
1398                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1399
1400         /* Free PS Poll skb here instead of returning RX_DROP that would
1401          * count as an dropped frame. */
1402         dev_kfree_skb(rx->skb);
1403
1404         return RX_QUEUED;
1405 }
1406
1407 static ieee80211_rx_result debug_noinline
1408 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1409 {
1410         u8 *data = rx->skb->data;
1411         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1412
1413         if (!ieee80211_is_data_qos(hdr->frame_control))
1414                 return RX_CONTINUE;
1415
1416         /* remove the qos control field, update frame type and meta-data */
1417         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1418                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1419         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1420         /* change frame type to non QOS */
1421         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1422
1423         return RX_CONTINUE;
1424 }
1425
1426 static int
1427 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1428 {
1429         if (unlikely(!rx->sta ||
1430             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1431                 return -EACCES;
1432
1433         return 0;
1434 }
1435
1436 static int
1437 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1438 {
1439         struct sk_buff *skb = rx->skb;
1440         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1441
1442         /*
1443          * Pass through unencrypted frames if the hardware has
1444          * decrypted them already.
1445          */
1446         if (status->flag & RX_FLAG_DECRYPTED)
1447                 return 0;
1448
1449         /* Drop unencrypted frames if key is set. */
1450         if (unlikely(!ieee80211_has_protected(fc) &&
1451                      !ieee80211_is_nullfunc(fc) &&
1452                      ieee80211_is_data(fc) &&
1453                      (rx->key || rx->sdata->drop_unencrypted)))
1454                 return -EACCES;
1455
1456         return 0;
1457 }
1458
1459 static int
1460 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1461 {
1462         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1463         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1464         __le16 fc = hdr->frame_control;
1465
1466         /*
1467          * Pass through unencrypted frames if the hardware has
1468          * decrypted them already.
1469          */
1470         if (status->flag & RX_FLAG_DECRYPTED)
1471                 return 0;
1472
1473         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1474                 if (unlikely(!ieee80211_has_protected(fc) &&
1475                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1476                              rx->key))
1477                         return -EACCES;
1478                 /* BIP does not use Protected field, so need to check MMIE */
1479                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1480                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1481                         return -EACCES;
1482                 /*
1483                  * When using MFP, Action frames are not allowed prior to
1484                  * having configured keys.
1485                  */
1486                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1487                              ieee80211_is_robust_mgmt_frame(
1488                                      (struct ieee80211_hdr *) rx->skb->data)))
1489                         return -EACCES;
1490         }
1491
1492         return 0;
1493 }
1494
1495 static int
1496 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1497 {
1498         struct ieee80211_sub_if_data *sdata = rx->sdata;
1499         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1500
1501         if (ieee80211_has_a4(hdr->frame_control) &&
1502             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1503                 return -1;
1504
1505         if (is_multicast_ether_addr(hdr->addr1) &&
1506             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1507              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1508                 return -1;
1509
1510         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1511 }
1512
1513 /*
1514  * requires that rx->skb is a frame with ethernet header
1515  */
1516 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1517 {
1518         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1519                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1520         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1521
1522         /*
1523          * Allow EAPOL frames to us/the PAE group address regardless
1524          * of whether the frame was encrypted or not.
1525          */
1526         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1527             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1528              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1529                 return true;
1530
1531         if (ieee80211_802_1x_port_control(rx) ||
1532             ieee80211_drop_unencrypted(rx, fc))
1533                 return false;
1534
1535         return true;
1536 }
1537
1538 /*
1539  * requires that rx->skb is a frame with ethernet header
1540  */
1541 static void
1542 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1543 {
1544         struct ieee80211_sub_if_data *sdata = rx->sdata;
1545         struct net_device *dev = sdata->dev;
1546         struct sk_buff *skb, *xmit_skb;
1547         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1548         struct sta_info *dsta;
1549
1550         skb = rx->skb;
1551         xmit_skb = NULL;
1552
1553         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1554              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1555             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1556             (rx->flags & IEEE80211_RX_RA_MATCH) &&
1557             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1558                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1559                         /*
1560                          * send multicast frames both to higher layers in
1561                          * local net stack and back to the wireless medium
1562                          */
1563                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1564                         if (!xmit_skb && net_ratelimit())
1565                                 printk(KERN_DEBUG "%s: failed to clone "
1566                                        "multicast frame\n", dev->name);
1567                 } else {
1568                         dsta = sta_info_get(sdata, skb->data);
1569                         if (dsta) {
1570                                 /*
1571                                  * The destination station is associated to
1572                                  * this AP (in this VLAN), so send the frame
1573                                  * directly to it and do not pass it to local
1574                                  * net stack.
1575                                  */
1576                                 xmit_skb = skb;
1577                                 skb = NULL;
1578                         }
1579                 }
1580         }
1581
1582         if (skb) {
1583                 int align __maybe_unused;
1584
1585 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1586                 /*
1587                  * 'align' will only take the values 0 or 2 here
1588                  * since all frames are required to be aligned
1589                  * to 2-byte boundaries when being passed to
1590                  * mac80211. That also explains the __skb_push()
1591                  * below.
1592                  */
1593                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1594                 if (align) {
1595                         if (WARN_ON(skb_headroom(skb) < 3)) {
1596                                 dev_kfree_skb(skb);
1597                                 skb = NULL;
1598                         } else {
1599                                 u8 *data = skb->data;
1600                                 size_t len = skb_headlen(skb);
1601                                 skb->data -= align;
1602                                 memmove(skb->data, data, len);
1603                                 skb_set_tail_pointer(skb, len);
1604                         }
1605                 }
1606 #endif
1607
1608                 if (skb) {
1609                         /* deliver to local stack */
1610                         skb->protocol = eth_type_trans(skb, dev);
1611                         memset(skb->cb, 0, sizeof(skb->cb));
1612                         netif_receive_skb(skb);
1613                 }
1614         }
1615
1616         if (xmit_skb) {
1617                 /* send to wireless media */
1618                 xmit_skb->protocol = htons(ETH_P_802_3);
1619                 skb_reset_network_header(xmit_skb);
1620                 skb_reset_mac_header(xmit_skb);
1621                 dev_queue_xmit(xmit_skb);
1622         }
1623 }
1624
1625 static ieee80211_rx_result debug_noinline
1626 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1627 {
1628         struct net_device *dev = rx->sdata->dev;
1629         struct sk_buff *skb = rx->skb;
1630         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1631         __le16 fc = hdr->frame_control;
1632         struct sk_buff_head frame_list;
1633
1634         if (unlikely(!ieee80211_is_data(fc)))
1635                 return RX_CONTINUE;
1636
1637         if (unlikely(!ieee80211_is_data_present(fc)))
1638                 return RX_DROP_MONITOR;
1639
1640         if (!(rx->flags & IEEE80211_RX_AMSDU))
1641                 return RX_CONTINUE;
1642
1643         if (ieee80211_has_a4(hdr->frame_control) &&
1644             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1645             !rx->sdata->u.vlan.sta)
1646                 return RX_DROP_UNUSABLE;
1647
1648         if (is_multicast_ether_addr(hdr->addr1) &&
1649             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1650               rx->sdata->u.vlan.sta) ||
1651              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1652               rx->sdata->u.mgd.use_4addr)))
1653                 return RX_DROP_UNUSABLE;
1654
1655         skb->dev = dev;
1656         __skb_queue_head_init(&frame_list);
1657
1658         if (skb_linearize(skb))
1659                 return RX_DROP_UNUSABLE;
1660
1661         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1662                                  rx->sdata->vif.type,
1663                                  rx->local->hw.extra_tx_headroom);
1664
1665         while (!skb_queue_empty(&frame_list)) {
1666                 rx->skb = __skb_dequeue(&frame_list);
1667
1668                 if (!ieee80211_frame_allowed(rx, fc)) {
1669                         dev_kfree_skb(rx->skb);
1670                         continue;
1671                 }
1672                 dev->stats.rx_packets++;
1673                 dev->stats.rx_bytes += rx->skb->len;
1674
1675                 ieee80211_deliver_skb(rx);
1676         }
1677
1678         return RX_QUEUED;
1679 }
1680
1681 #ifdef CONFIG_MAC80211_MESH
1682 static ieee80211_rx_result
1683 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1684 {
1685         struct ieee80211_hdr *hdr;
1686         struct ieee80211s_hdr *mesh_hdr;
1687         unsigned int hdrlen;
1688         struct sk_buff *skb = rx->skb, *fwd_skb;
1689         struct ieee80211_local *local = rx->local;
1690         struct ieee80211_sub_if_data *sdata = rx->sdata;
1691
1692         hdr = (struct ieee80211_hdr *) skb->data;
1693         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1694         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1695
1696         if (!ieee80211_is_data(hdr->frame_control))
1697                 return RX_CONTINUE;
1698
1699         if (!mesh_hdr->ttl)
1700                 /* illegal frame */
1701                 return RX_DROP_MONITOR;
1702
1703         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1704                 struct mesh_path *mppath;
1705                 char *proxied_addr;
1706                 char *mpp_addr;
1707
1708                 if (is_multicast_ether_addr(hdr->addr1)) {
1709                         mpp_addr = hdr->addr3;
1710                         proxied_addr = mesh_hdr->eaddr1;
1711                 } else {
1712                         mpp_addr = hdr->addr4;
1713                         proxied_addr = mesh_hdr->eaddr2;
1714                 }
1715
1716                 rcu_read_lock();
1717                 mppath = mpp_path_lookup(proxied_addr, sdata);
1718                 if (!mppath) {
1719                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1720                 } else {
1721                         spin_lock_bh(&mppath->state_lock);
1722                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1723                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1724                         spin_unlock_bh(&mppath->state_lock);
1725                 }
1726                 rcu_read_unlock();
1727         }
1728
1729         /* Frame has reached destination.  Don't forward */
1730         if (!is_multicast_ether_addr(hdr->addr1) &&
1731             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1732                 return RX_CONTINUE;
1733
1734         mesh_hdr->ttl--;
1735
1736         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1737                 if (!mesh_hdr->ttl)
1738                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1739                                                      dropped_frames_ttl);
1740                 else {
1741                         struct ieee80211_hdr *fwd_hdr;
1742                         struct ieee80211_tx_info *info;
1743
1744                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1745
1746                         if (!fwd_skb && net_ratelimit())
1747                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1748                                                    sdata->name);
1749
1750                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1751                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1752                         info = IEEE80211_SKB_CB(fwd_skb);
1753                         memset(info, 0, sizeof(*info));
1754                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1755                         info->control.vif = &rx->sdata->vif;
1756                         skb_set_queue_mapping(skb,
1757                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1758                         ieee80211_set_qos_hdr(local, skb);
1759                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1760                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1761                                                                 fwded_mcast);
1762                         else {
1763                                 int err;
1764                                 /*
1765                                  * Save TA to addr1 to send TA a path error if a
1766                                  * suitable next hop is not found
1767                                  */
1768                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1769                                                 ETH_ALEN);
1770                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1771                                 /* Failed to immediately resolve next hop:
1772                                  * fwded frame was dropped or will be added
1773                                  * later to the pending skb queue.  */
1774                                 if (err)
1775                                         return RX_DROP_MONITOR;
1776
1777                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1778                                                                 fwded_unicast);
1779                         }
1780                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1781                                                      fwded_frames);
1782                         ieee80211_add_pending_skb(local, fwd_skb);
1783                 }
1784         }
1785
1786         if (is_multicast_ether_addr(hdr->addr1) ||
1787             sdata->dev->flags & IFF_PROMISC)
1788                 return RX_CONTINUE;
1789         else
1790                 return RX_DROP_MONITOR;
1791 }
1792 #endif
1793
1794 static ieee80211_rx_result debug_noinline
1795 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1796 {
1797         struct ieee80211_sub_if_data *sdata = rx->sdata;
1798         struct ieee80211_local *local = rx->local;
1799         struct net_device *dev = sdata->dev;
1800         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1801         __le16 fc = hdr->frame_control;
1802         int err;
1803
1804         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1805                 return RX_CONTINUE;
1806
1807         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1808                 return RX_DROP_MONITOR;
1809
1810         /*
1811          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1812          * that a 4-addr station can be detected and moved into a separate VLAN
1813          */
1814         if (ieee80211_has_a4(hdr->frame_control) &&
1815             sdata->vif.type == NL80211_IFTYPE_AP)
1816                 return RX_DROP_MONITOR;
1817
1818         err = __ieee80211_data_to_8023(rx);
1819         if (unlikely(err))
1820                 return RX_DROP_UNUSABLE;
1821
1822         if (!ieee80211_frame_allowed(rx, fc))
1823                 return RX_DROP_MONITOR;
1824
1825         rx->skb->dev = dev;
1826
1827         dev->stats.rx_packets++;
1828         dev->stats.rx_bytes += rx->skb->len;
1829
1830         if (ieee80211_is_data(hdr->frame_control) &&
1831             !is_multicast_ether_addr(hdr->addr1) &&
1832             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1833                         mod_timer(&local->dynamic_ps_timer, jiffies +
1834                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1835         }
1836
1837         ieee80211_deliver_skb(rx);
1838
1839         return RX_QUEUED;
1840 }
1841
1842 static ieee80211_rx_result debug_noinline
1843 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1844 {
1845         struct ieee80211_local *local = rx->local;
1846         struct ieee80211_hw *hw = &local->hw;
1847         struct sk_buff *skb = rx->skb;
1848         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1849         struct tid_ampdu_rx *tid_agg_rx;
1850         u16 start_seq_num;
1851         u16 tid;
1852
1853         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1854                 return RX_CONTINUE;
1855
1856         if (ieee80211_is_back_req(bar->frame_control)) {
1857                 struct {
1858                         __le16 control, start_seq_num;
1859                 } __packed bar_data;
1860
1861                 if (!rx->sta)
1862                         return RX_DROP_MONITOR;
1863
1864                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1865                                   &bar_data, sizeof(bar_data)))
1866                         return RX_DROP_MONITOR;
1867
1868                 tid = le16_to_cpu(bar_data.control) >> 12;
1869
1870                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1871                 if (!tid_agg_rx)
1872                         return RX_DROP_MONITOR;
1873
1874                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1875
1876                 /* reset session timer */
1877                 if (tid_agg_rx->timeout)
1878                         mod_timer(&tid_agg_rx->session_timer,
1879                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1880
1881                 /* release stored frames up to start of BAR */
1882                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1883                                                  frames);
1884                 kfree_skb(skb);
1885                 return RX_QUEUED;
1886         }
1887
1888         /*
1889          * After this point, we only want management frames,
1890          * so we can drop all remaining control frames to
1891          * cooked monitor interfaces.
1892          */
1893         return RX_DROP_MONITOR;
1894 }
1895
1896 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1897                                            struct ieee80211_mgmt *mgmt,
1898                                            size_t len)
1899 {
1900         struct ieee80211_local *local = sdata->local;
1901         struct sk_buff *skb;
1902         struct ieee80211_mgmt *resp;
1903
1904         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1905                 /* Not to own unicast address */
1906                 return;
1907         }
1908
1909         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1910             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1911                 /* Not from the current AP or not associated yet. */
1912                 return;
1913         }
1914
1915         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1916                 /* Too short SA Query request frame */
1917                 return;
1918         }
1919
1920         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1921         if (skb == NULL)
1922                 return;
1923
1924         skb_reserve(skb, local->hw.extra_tx_headroom);
1925         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1926         memset(resp, 0, 24);
1927         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1928         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1929         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1930         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1931                                           IEEE80211_STYPE_ACTION);
1932         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1933         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1934         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1935         memcpy(resp->u.action.u.sa_query.trans_id,
1936                mgmt->u.action.u.sa_query.trans_id,
1937                WLAN_SA_QUERY_TR_ID_LEN);
1938
1939         ieee80211_tx_skb(sdata, skb);
1940 }
1941
1942 static ieee80211_rx_result debug_noinline
1943 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1944 {
1945         struct ieee80211_local *local = rx->local;
1946         struct ieee80211_sub_if_data *sdata = rx->sdata;
1947         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1948         struct sk_buff *nskb;
1949         struct ieee80211_rx_status *status;
1950         int len = rx->skb->len;
1951
1952         if (!ieee80211_is_action(mgmt->frame_control))
1953                 return RX_CONTINUE;
1954
1955         /* drop too small frames */
1956         if (len < IEEE80211_MIN_ACTION_SIZE)
1957                 return RX_DROP_UNUSABLE;
1958
1959         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
1960                 return RX_DROP_UNUSABLE;
1961
1962         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1963                 return RX_DROP_UNUSABLE;
1964
1965         if (ieee80211_drop_unencrypted_mgmt(rx))
1966                 return RX_DROP_UNUSABLE;
1967
1968         switch (mgmt->u.action.category) {
1969         case WLAN_CATEGORY_BACK:
1970                 /*
1971                  * The aggregation code is not prepared to handle
1972                  * anything but STA/AP due to the BSSID handling;
1973                  * IBSS could work in the code but isn't supported
1974                  * by drivers or the standard.
1975                  */
1976                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1977                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1978                     sdata->vif.type != NL80211_IFTYPE_AP)
1979                         break;
1980
1981                 /* verify action_code is present */
1982                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1983                         break;
1984
1985                 switch (mgmt->u.action.u.addba_req.action_code) {
1986                 case WLAN_ACTION_ADDBA_REQ:
1987                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1988                                    sizeof(mgmt->u.action.u.addba_req)))
1989                                 goto invalid;
1990                         break;
1991                 case WLAN_ACTION_ADDBA_RESP:
1992                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1993                                    sizeof(mgmt->u.action.u.addba_resp)))
1994                                 goto invalid;
1995                         break;
1996                 case WLAN_ACTION_DELBA:
1997                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1998                                    sizeof(mgmt->u.action.u.delba)))
1999                                 goto invalid;
2000                         break;
2001                 default:
2002                         goto invalid;
2003                 }
2004
2005                 goto queue;
2006         case WLAN_CATEGORY_SPECTRUM_MGMT:
2007                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2008                         break;
2009
2010                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2011                         break;
2012
2013                 /* verify action_code is present */
2014                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2015                         break;
2016
2017                 switch (mgmt->u.action.u.measurement.action_code) {
2018                 case WLAN_ACTION_SPCT_MSR_REQ:
2019                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2020                                    sizeof(mgmt->u.action.u.measurement)))
2021                                 break;
2022                         ieee80211_process_measurement_req(sdata, mgmt, len);
2023                         goto handled;
2024                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2025                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2026                                    sizeof(mgmt->u.action.u.chan_switch)))
2027                                 break;
2028
2029                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2030                                 break;
2031
2032                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2033                                 break;
2034
2035                         goto queue;
2036                 }
2037                 break;
2038         case WLAN_CATEGORY_SA_QUERY:
2039                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2040                            sizeof(mgmt->u.action.u.sa_query)))
2041                         break;
2042
2043                 switch (mgmt->u.action.u.sa_query.action) {
2044                 case WLAN_ACTION_SA_QUERY_REQUEST:
2045                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2046                                 break;
2047                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2048                         goto handled;
2049                 }
2050                 break;
2051         case WLAN_CATEGORY_MESH_PLINK:
2052         case WLAN_CATEGORY_MESH_PATH_SEL:
2053                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2054                         break;
2055                 goto queue;
2056         }
2057
2058  invalid:
2059         /*
2060          * For AP mode, hostapd is responsible for handling any action
2061          * frames that we didn't handle, including returning unknown
2062          * ones. For all other modes we will return them to the sender,
2063          * setting the 0x80 bit in the action category, as required by
2064          * 802.11-2007 7.3.1.11.
2065          */
2066         if (sdata->vif.type == NL80211_IFTYPE_AP ||
2067             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2068                 return RX_DROP_MONITOR;
2069
2070         /*
2071          * Getting here means the kernel doesn't know how to handle
2072          * it, but maybe userspace does ... include returned frames
2073          * so userspace can register for those to know whether ones
2074          * it transmitted were processed or returned.
2075          */
2076         status = IEEE80211_SKB_RXCB(rx->skb);
2077
2078         if (cfg80211_rx_action(rx->sdata->dev, status->freq,
2079                                rx->skb->data, rx->skb->len,
2080                                GFP_ATOMIC))
2081                 goto handled;
2082
2083         /* do not return rejected action frames */
2084         if (mgmt->u.action.category & 0x80)
2085                 return RX_DROP_UNUSABLE;
2086
2087         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2088                                GFP_ATOMIC);
2089         if (nskb) {
2090                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2091
2092                 nmgmt->u.action.category |= 0x80;
2093                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2094                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2095
2096                 memset(nskb->cb, 0, sizeof(nskb->cb));
2097
2098                 ieee80211_tx_skb(rx->sdata, nskb);
2099         }
2100
2101  handled:
2102         if (rx->sta)
2103                 rx->sta->rx_packets++;
2104         dev_kfree_skb(rx->skb);
2105         return RX_QUEUED;
2106
2107  queue:
2108         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2109         skb_queue_tail(&sdata->skb_queue, rx->skb);
2110         ieee80211_queue_work(&local->hw, &sdata->work);
2111         if (rx->sta)
2112                 rx->sta->rx_packets++;
2113         return RX_QUEUED;
2114 }
2115
2116 static ieee80211_rx_result debug_noinline
2117 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2118 {
2119         struct ieee80211_sub_if_data *sdata = rx->sdata;
2120         ieee80211_rx_result rxs;
2121         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2122         __le16 stype;
2123
2124         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
2125                 return RX_DROP_MONITOR;
2126
2127         if (rx->skb->len < 24)
2128                 return RX_DROP_MONITOR;
2129
2130         if (ieee80211_drop_unencrypted_mgmt(rx))
2131                 return RX_DROP_UNUSABLE;
2132
2133         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2134         if (rxs != RX_CONTINUE)
2135                 return rxs;
2136
2137         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2138
2139         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2140             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2141             sdata->vif.type != NL80211_IFTYPE_STATION)
2142                 return RX_DROP_MONITOR;
2143
2144         switch (stype) {
2145         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2146         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2147                 /* process for all: mesh, mlme, ibss */
2148                 break;
2149         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2150         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2151                 /* process only for station */
2152                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2153                         return RX_DROP_MONITOR;
2154                 break;
2155         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2156         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2157                 /* process only for ibss */
2158                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2159                         return RX_DROP_MONITOR;
2160                 break;
2161         default:
2162                 return RX_DROP_MONITOR;
2163         }
2164
2165         /* queue up frame and kick off work to process it */
2166         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2167         skb_queue_tail(&sdata->skb_queue, rx->skb);
2168         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2169         if (rx->sta)
2170                 rx->sta->rx_packets++;
2171
2172         return RX_QUEUED;
2173 }
2174
2175 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2176                                             struct ieee80211_rx_data *rx)
2177 {
2178         int keyidx;
2179         unsigned int hdrlen;
2180
2181         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2182         if (rx->skb->len >= hdrlen + 4)
2183                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2184         else
2185                 keyidx = -1;
2186
2187         if (!rx->sta) {
2188                 /*
2189                  * Some hardware seem to generate incorrect Michael MIC
2190                  * reports; ignore them to avoid triggering countermeasures.
2191                  */
2192                 return;
2193         }
2194
2195         if (!ieee80211_has_protected(hdr->frame_control))
2196                 return;
2197
2198         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2199                 /*
2200                  * APs with pairwise keys should never receive Michael MIC
2201                  * errors for non-zero keyidx because these are reserved for
2202                  * group keys and only the AP is sending real multicast
2203                  * frames in the BSS.
2204                  */
2205                 return;
2206         }
2207
2208         if (!ieee80211_is_data(hdr->frame_control) &&
2209             !ieee80211_is_auth(hdr->frame_control))
2210                 return;
2211
2212         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2213                                         GFP_ATOMIC);
2214 }
2215
2216 /* TODO: use IEEE80211_RX_FRAGMENTED */
2217 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2218                                         struct ieee80211_rate *rate)
2219 {
2220         struct ieee80211_sub_if_data *sdata;
2221         struct ieee80211_local *local = rx->local;
2222         struct ieee80211_rtap_hdr {
2223                 struct ieee80211_radiotap_header hdr;
2224                 u8 flags;
2225                 u8 rate_or_pad;
2226                 __le16 chan_freq;
2227                 __le16 chan_flags;
2228         } __packed *rthdr;
2229         struct sk_buff *skb = rx->skb, *skb2;
2230         struct net_device *prev_dev = NULL;
2231         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2232
2233         if (status->flag & RX_FLAG_INTERNAL_CMTR)
2234                 goto out_free_skb;
2235
2236         if (skb_headroom(skb) < sizeof(*rthdr) &&
2237             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2238                 goto out_free_skb;
2239
2240         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2241         memset(rthdr, 0, sizeof(*rthdr));
2242         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2243         rthdr->hdr.it_present =
2244                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2245                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2246
2247         if (rate) {
2248                 rthdr->rate_or_pad = rate->bitrate / 5;
2249                 rthdr->hdr.it_present |=
2250                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2251         }
2252         rthdr->chan_freq = cpu_to_le16(status->freq);
2253
2254         if (status->band == IEEE80211_BAND_5GHZ)
2255                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2256                                                 IEEE80211_CHAN_5GHZ);
2257         else
2258                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2259                                                 IEEE80211_CHAN_2GHZ);
2260
2261         skb_set_mac_header(skb, 0);
2262         skb->ip_summed = CHECKSUM_UNNECESSARY;
2263         skb->pkt_type = PACKET_OTHERHOST;
2264         skb->protocol = htons(ETH_P_802_2);
2265
2266         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2267                 if (!ieee80211_sdata_running(sdata))
2268                         continue;
2269
2270                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2271                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2272                         continue;
2273
2274                 if (prev_dev) {
2275                         skb2 = skb_clone(skb, GFP_ATOMIC);
2276                         if (skb2) {
2277                                 skb2->dev = prev_dev;
2278                                 netif_receive_skb(skb2);
2279                         }
2280                 }
2281
2282                 prev_dev = sdata->dev;
2283                 sdata->dev->stats.rx_packets++;
2284                 sdata->dev->stats.rx_bytes += skb->len;
2285         }
2286
2287         if (prev_dev) {
2288                 skb->dev = prev_dev;
2289                 netif_receive_skb(skb);
2290                 skb = NULL;
2291         } else
2292                 goto out_free_skb;
2293
2294         status->flag |= RX_FLAG_INTERNAL_CMTR;
2295         return;
2296
2297  out_free_skb:
2298         dev_kfree_skb(skb);
2299 }
2300
2301 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2302                                          ieee80211_rx_result res)
2303 {
2304         switch (res) {
2305         case RX_DROP_MONITOR:
2306                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2307                 if (rx->sta)
2308                         rx->sta->rx_dropped++;
2309                 /* fall through */
2310         case RX_CONTINUE: {
2311                 struct ieee80211_rate *rate = NULL;
2312                 struct ieee80211_supported_band *sband;
2313                 struct ieee80211_rx_status *status;
2314
2315                 status = IEEE80211_SKB_RXCB((rx->skb));
2316
2317                 sband = rx->local->hw.wiphy->bands[status->band];
2318                 if (!(status->flag & RX_FLAG_HT))
2319                         rate = &sband->bitrates[status->rate_idx];
2320
2321                 ieee80211_rx_cooked_monitor(rx, rate);
2322                 break;
2323                 }
2324         case RX_DROP_UNUSABLE:
2325                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2326                 if (rx->sta)
2327                         rx->sta->rx_dropped++;
2328                 dev_kfree_skb(rx->skb);
2329                 break;
2330         case RX_QUEUED:
2331                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2332                 break;
2333         }
2334 }
2335
2336 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2337                                   struct sk_buff_head *frames)
2338 {
2339         ieee80211_rx_result res = RX_DROP_MONITOR;
2340         struct sk_buff *skb;
2341
2342 #define CALL_RXH(rxh)                   \
2343         do {                            \
2344                 res = rxh(rx);          \
2345                 if (res != RX_CONTINUE) \
2346                         goto rxh_next;  \
2347         } while (0);
2348
2349         while ((skb = __skb_dequeue(frames))) {
2350                 /*
2351                  * all the other fields are valid across frames
2352                  * that belong to an aMPDU since they are on the
2353                  * same TID from the same station
2354                  */
2355                 rx->skb = skb;
2356
2357                 CALL_RXH(ieee80211_rx_h_decrypt)
2358                 CALL_RXH(ieee80211_rx_h_check_more_data)
2359                 CALL_RXH(ieee80211_rx_h_sta_process)
2360                 CALL_RXH(ieee80211_rx_h_defragment)
2361                 CALL_RXH(ieee80211_rx_h_ps_poll)
2362                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2363                 /* must be after MMIC verify so header is counted in MPDU mic */
2364                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2365                 CALL_RXH(ieee80211_rx_h_amsdu)
2366 #ifdef CONFIG_MAC80211_MESH
2367                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2368                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2369 #endif
2370                 CALL_RXH(ieee80211_rx_h_data)
2371
2372                 /* special treatment -- needs the queue */
2373                 res = ieee80211_rx_h_ctrl(rx, frames);
2374                 if (res != RX_CONTINUE)
2375                         goto rxh_next;
2376
2377                 CALL_RXH(ieee80211_rx_h_action)
2378                 CALL_RXH(ieee80211_rx_h_mgmt)
2379
2380  rxh_next:
2381                 ieee80211_rx_handlers_result(rx, res);
2382
2383 #undef CALL_RXH
2384         }
2385 }
2386
2387 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2388                                          struct ieee80211_rx_data *rx,
2389                                          struct sk_buff *skb)
2390 {
2391         struct sk_buff_head reorder_release;
2392         ieee80211_rx_result res = RX_DROP_MONITOR;
2393
2394         __skb_queue_head_init(&reorder_release);
2395
2396         rx->skb = skb;
2397         rx->sdata = sdata;
2398
2399 #define CALL_RXH(rxh)                   \
2400         do {                            \
2401                 res = rxh(rx);          \
2402                 if (res != RX_CONTINUE) \
2403                         goto rxh_next;  \
2404         } while (0);
2405
2406         CALL_RXH(ieee80211_rx_h_passive_scan)
2407         CALL_RXH(ieee80211_rx_h_check)
2408
2409         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2410
2411         ieee80211_rx_handlers(rx, &reorder_release);
2412         return;
2413
2414  rxh_next:
2415         ieee80211_rx_handlers_result(rx, res);
2416
2417 #undef CALL_RXH
2418 }
2419
2420 /*
2421  * This function makes calls into the RX path. Therefore the
2422  * caller must hold the sta_info->lock and everything has to
2423  * be under rcu_read_lock protection as well.
2424  */
2425 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2426 {
2427         struct sk_buff_head frames;
2428         struct ieee80211_rx_data rx = { };
2429
2430         __skb_queue_head_init(&frames);
2431
2432         /* construct rx struct */
2433         rx.sta = sta;
2434         rx.sdata = sta->sdata;
2435         rx.local = sta->local;
2436         rx.queue = tid;
2437         rx.flags |= IEEE80211_RX_RA_MATCH;
2438
2439         if (unlikely(test_bit(SCAN_HW_SCANNING, &sta->local->scanning) ||
2440                      test_bit(SCAN_OFF_CHANNEL, &sta->local->scanning)))
2441                 rx.flags |= IEEE80211_RX_IN_SCAN;
2442
2443         spin_lock(&sta->ampdu_mlme.tid_rx[tid]->reorder_lock);
2444         ieee80211_sta_reorder_release(&sta->local->hw,
2445                 sta->ampdu_mlme.tid_rx[tid], &frames);
2446         spin_unlock(&sta->ampdu_mlme.tid_rx[tid]->reorder_lock);
2447
2448         ieee80211_rx_handlers(&rx, &frames);
2449 }
2450
2451 /* main receive path */
2452
2453 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2454                                 struct ieee80211_rx_data *rx,
2455                                 struct ieee80211_hdr *hdr)
2456 {
2457         struct sk_buff *skb = rx->skb;
2458         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2459         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2460         int multicast = is_multicast_ether_addr(hdr->addr1);
2461
2462         switch (sdata->vif.type) {
2463         case NL80211_IFTYPE_STATION:
2464                 if (!bssid && !sdata->u.mgd.use_4addr)
2465                         return 0;
2466                 if (!multicast &&
2467                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2468                         if (!(sdata->dev->flags & IFF_PROMISC))
2469                                 return 0;
2470                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2471                 }
2472                 break;
2473         case NL80211_IFTYPE_ADHOC:
2474                 if (!bssid)
2475                         return 0;
2476                 if (ieee80211_is_beacon(hdr->frame_control)) {
2477                         return 1;
2478                 }
2479                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2480                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2481                                 return 0;
2482                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2483                 } else if (!multicast &&
2484                            compare_ether_addr(sdata->vif.addr,
2485                                               hdr->addr1) != 0) {
2486                         if (!(sdata->dev->flags & IFF_PROMISC))
2487                                 return 0;
2488                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2489                 } else if (!rx->sta) {
2490                         int rate_idx;
2491                         if (status->flag & RX_FLAG_HT)
2492                                 rate_idx = 0; /* TODO: HT rates */
2493                         else
2494                                 rate_idx = status->rate_idx;
2495                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2496                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2497                 }
2498                 break;
2499         case NL80211_IFTYPE_MESH_POINT:
2500                 if (!multicast &&
2501                     compare_ether_addr(sdata->vif.addr,
2502                                        hdr->addr1) != 0) {
2503                         if (!(sdata->dev->flags & IFF_PROMISC))
2504                                 return 0;
2505
2506                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2507                 }
2508                 break;
2509         case NL80211_IFTYPE_AP_VLAN:
2510         case NL80211_IFTYPE_AP:
2511                 if (!bssid) {
2512                         if (compare_ether_addr(sdata->vif.addr,
2513                                                hdr->addr1))
2514                                 return 0;
2515                 } else if (!ieee80211_bssid_match(bssid,
2516                                         sdata->vif.addr)) {
2517                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2518                                 return 0;
2519                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2520                 }
2521                 break;
2522         case NL80211_IFTYPE_WDS:
2523                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2524                         return 0;
2525                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2526                         return 0;
2527                 break;
2528         case NL80211_IFTYPE_MONITOR:
2529         case NL80211_IFTYPE_UNSPECIFIED:
2530         case __NL80211_IFTYPE_AFTER_LAST:
2531                 /* should never get here */
2532                 WARN_ON(1);
2533                 break;
2534         }
2535
2536         return 1;
2537 }
2538
2539 /*
2540  * This is the actual Rx frames handler. as it blongs to Rx path it must
2541  * be called with rcu_read_lock protection.
2542  */
2543 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2544                                          struct sk_buff *skb)
2545 {
2546         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2547         struct ieee80211_local *local = hw_to_local(hw);
2548         struct ieee80211_sub_if_data *sdata;
2549         struct ieee80211_hdr *hdr;
2550         __le16 fc;
2551         struct ieee80211_rx_data rx;
2552         int prepares;
2553         struct ieee80211_sub_if_data *prev = NULL;
2554         struct sk_buff *skb_new;
2555         struct sta_info *sta, *tmp;
2556         bool found_sta = false;
2557         int err = 0;
2558
2559         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2560         memset(&rx, 0, sizeof(rx));
2561         rx.skb = skb;
2562         rx.local = local;
2563
2564         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2565                 local->dot11ReceivedFragmentCount++;
2566
2567         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2568                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2569                 rx.flags |= IEEE80211_RX_IN_SCAN;
2570
2571         if (ieee80211_is_mgmt(fc))
2572                 err = skb_linearize(skb);
2573         else
2574                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2575
2576         if (err) {
2577                 dev_kfree_skb(skb);
2578                 return;
2579         }
2580
2581         hdr = (struct ieee80211_hdr *)skb->data;
2582         ieee80211_parse_qos(&rx);
2583         ieee80211_verify_alignment(&rx);
2584
2585         if (ieee80211_is_data(fc)) {
2586                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2587                         rx.sta = sta;
2588                         found_sta = true;
2589                         rx.sdata = sta->sdata;
2590
2591                         rx.flags |= IEEE80211_RX_RA_MATCH;
2592                         prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2593                         if (prepares) {
2594                                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2595                                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2596                                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2597                                 } else
2598                                         prev = rx.sdata;
2599                         }
2600                 }
2601         }
2602         if (!found_sta) {
2603                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2604                         if (!ieee80211_sdata_running(sdata))
2605                                 continue;
2606
2607                         if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2608                             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2609                                 continue;
2610
2611                         /*
2612                          * frame is destined for this interface, but if it's
2613                          * not also for the previous one we handle that after
2614                          * the loop to avoid copying the SKB once too much
2615                          */
2616
2617                         if (!prev) {
2618                                 prev = sdata;
2619                                 continue;
2620                         }
2621
2622                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2623
2624                         rx.flags |= IEEE80211_RX_RA_MATCH;
2625                         prepares = prepare_for_handlers(prev, &rx, hdr);
2626
2627                         if (!prepares)
2628                                 goto next;
2629
2630                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2631                                 rx.sdata = prev;
2632                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2633                                         ieee80211_rx_michael_mic_report(hdr,
2634                                                                         &rx);
2635                                 goto next;
2636                         }
2637
2638                         /*
2639                          * frame was destined for the previous interface
2640                          * so invoke RX handlers for it
2641                          */
2642
2643                         skb_new = skb_copy(skb, GFP_ATOMIC);
2644                         if (!skb_new) {
2645                                 if (net_ratelimit())
2646                                         printk(KERN_DEBUG "%s: failed to copy "
2647                                                "multicast frame for %s\n",
2648                                                wiphy_name(local->hw.wiphy),
2649                                                prev->name);
2650                                 goto next;
2651                         }
2652                         ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2653 next:
2654                         prev = sdata;
2655                 }
2656
2657                 if (prev) {
2658                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2659
2660                         rx.flags |= IEEE80211_RX_RA_MATCH;
2661                         prepares = prepare_for_handlers(prev, &rx, hdr);
2662
2663                         if (!prepares)
2664                                 prev = NULL;
2665                 }
2666         }
2667         if (prev)
2668                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2669         else
2670                 dev_kfree_skb(skb);
2671 }
2672
2673 /*
2674  * This is the receive path handler. It is called by a low level driver when an
2675  * 802.11 MPDU is received from the hardware.
2676  */
2677 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2678 {
2679         struct ieee80211_local *local = hw_to_local(hw);
2680         struct ieee80211_rate *rate = NULL;
2681         struct ieee80211_supported_band *sband;
2682         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2683
2684         WARN_ON_ONCE(softirq_count() == 0);
2685
2686         if (WARN_ON(status->band < 0 ||
2687                     status->band >= IEEE80211_NUM_BANDS))
2688                 goto drop;
2689
2690         sband = local->hw.wiphy->bands[status->band];
2691         if (WARN_ON(!sband))
2692                 goto drop;
2693
2694         /*
2695          * If we're suspending, it is possible although not too likely
2696          * that we'd be receiving frames after having already partially
2697          * quiesced the stack. We can't process such frames then since
2698          * that might, for example, cause stations to be added or other
2699          * driver callbacks be invoked.
2700          */
2701         if (unlikely(local->quiescing || local->suspended))
2702                 goto drop;
2703
2704         /*
2705          * The same happens when we're not even started,
2706          * but that's worth a warning.
2707          */
2708         if (WARN_ON(!local->started))
2709                 goto drop;
2710
2711         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2712                 /*
2713                  * Validate the rate, unless a PLCP error means that
2714                  * we probably can't have a valid rate here anyway.
2715                  */
2716
2717                 if (status->flag & RX_FLAG_HT) {
2718                         /*
2719                          * rate_idx is MCS index, which can be [0-76]
2720                          * as documented on:
2721                          *
2722                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2723                          *
2724                          * Anything else would be some sort of driver or
2725                          * hardware error. The driver should catch hardware
2726                          * errors.
2727                          */
2728                         if (WARN((status->rate_idx < 0 ||
2729                                  status->rate_idx > 76),
2730                                  "Rate marked as an HT rate but passed "
2731                                  "status->rate_idx is not "
2732                                  "an MCS index [0-76]: %d (0x%02x)\n",
2733                                  status->rate_idx,
2734                                  status->rate_idx))
2735                                 goto drop;
2736                 } else {
2737                         if (WARN_ON(status->rate_idx < 0 ||
2738                                     status->rate_idx >= sband->n_bitrates))
2739                                 goto drop;
2740                         rate = &sband->bitrates[status->rate_idx];
2741                 }
2742         }
2743
2744         /*
2745          * key references and virtual interfaces are protected using RCU
2746          * and this requires that we are in a read-side RCU section during
2747          * receive processing
2748          */
2749         rcu_read_lock();
2750
2751         /*
2752          * Frames with failed FCS/PLCP checksum are not returned,
2753          * all other frames are returned without radiotap header
2754          * if it was previously present.
2755          * Also, frames with less than 16 bytes are dropped.
2756          */
2757         skb = ieee80211_rx_monitor(local, skb, rate);
2758         if (!skb) {
2759                 rcu_read_unlock();
2760                 return;
2761         }
2762
2763         __ieee80211_rx_handle_packet(hw, skb);
2764
2765         rcu_read_unlock();
2766
2767         return;
2768  drop:
2769         kfree_skb(skb);
2770 }
2771 EXPORT_SYMBOL(ieee80211_rx);
2772
2773 /* This is a version of the rx handler that can be called from hard irq
2774  * context. Post the skb on the queue and schedule the tasklet */
2775 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2776 {
2777         struct ieee80211_local *local = hw_to_local(hw);
2778
2779         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2780
2781         skb->pkt_type = IEEE80211_RX_MSG;
2782         skb_queue_tail(&local->skb_queue, skb);
2783         tasklet_schedule(&local->tasklet);
2784 }
2785 EXPORT_SYMBOL(ieee80211_rx_irqsafe);