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mac80211: MFP - Drop unprotected Action frames prior key setup
[GitHub/LineageOS/android_kernel_samsung_universal7580.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 Johannes Berg <johannes@sipsolutions.net>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/jiffies.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rcupdate.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20
21 #include "ieee80211_i.h"
22 #include "driver-ops.h"
23 #include "led.h"
24 #include "mesh.h"
25 #include "wep.h"
26 #include "wpa.h"
27 #include "tkip.h"
28 #include "wme.h"
29
30 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
31 struct tid_ampdu_rx *tid_agg_rx,
32 struct sk_buff *skb,
33 struct ieee80211_rx_status *status,
34 u16 mpdu_seq_num,
35 int bar_req);
36 /*
37 * monitor mode reception
38 *
39 * This function cleans up the SKB, i.e. it removes all the stuff
40 * only useful for monitoring.
41 */
42 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
43 struct sk_buff *skb,
44 int rtap_len)
45 {
46 skb_pull(skb, rtap_len);
47
48 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
49 if (likely(skb->len > FCS_LEN))
50 skb_trim(skb, skb->len - FCS_LEN);
51 else {
52 /* driver bug */
53 WARN_ON(1);
54 dev_kfree_skb(skb);
55 skb = NULL;
56 }
57 }
58
59 return skb;
60 }
61
62 static inline int should_drop_frame(struct ieee80211_rx_status *status,
63 struct sk_buff *skb,
64 int present_fcs_len,
65 int radiotap_len)
66 {
67 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
68
69 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
70 return 1;
71 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
72 return 1;
73 if (ieee80211_is_ctl(hdr->frame_control) &&
74 !ieee80211_is_pspoll(hdr->frame_control) &&
75 !ieee80211_is_back_req(hdr->frame_control))
76 return 1;
77 return 0;
78 }
79
80 static int
81 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
82 struct ieee80211_rx_status *status)
83 {
84 int len;
85
86 /* always present fields */
87 len = sizeof(struct ieee80211_radiotap_header) + 9;
88
89 if (status->flag & RX_FLAG_TSFT)
90 len += 8;
91 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
92 len += 1;
93 if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
94 len += 1;
95
96 if (len & 1) /* padding for RX_FLAGS if necessary */
97 len++;
98
99 /* make sure radiotap starts at a naturally aligned address */
100 if (len % 8)
101 len = roundup(len, 8);
102
103 return len;
104 }
105
106 /*
107 * ieee80211_add_rx_radiotap_header - add radiotap header
108 *
109 * add a radiotap header containing all the fields which the hardware provided.
110 */
111 static void
112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
113 struct sk_buff *skb,
114 struct ieee80211_rx_status *status,
115 struct ieee80211_rate *rate,
116 int rtap_len)
117 {
118 struct ieee80211_radiotap_header *rthdr;
119 unsigned char *pos;
120
121 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
122 memset(rthdr, 0, rtap_len);
123
124 /* radiotap header, set always present flags */
125 rthdr->it_present =
126 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
127 (1 << IEEE80211_RADIOTAP_CHANNEL) |
128 (1 << IEEE80211_RADIOTAP_ANTENNA) |
129 (1 << IEEE80211_RADIOTAP_RX_FLAGS));
130 rthdr->it_len = cpu_to_le16(rtap_len);
131
132 pos = (unsigned char *)(rthdr+1);
133
134 /* the order of the following fields is important */
135
136 /* IEEE80211_RADIOTAP_TSFT */
137 if (status->flag & RX_FLAG_TSFT) {
138 *(__le64 *)pos = cpu_to_le64(status->mactime);
139 rthdr->it_present |=
140 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
141 pos += 8;
142 }
143
144 /* IEEE80211_RADIOTAP_FLAGS */
145 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
146 *pos |= IEEE80211_RADIOTAP_F_FCS;
147 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
148 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
149 if (status->flag & RX_FLAG_SHORTPRE)
150 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
151 pos++;
152
153 /* IEEE80211_RADIOTAP_RATE */
154 if (status->flag & RX_FLAG_HT) {
155 /*
156 * TODO: add following information into radiotap header once
157 * suitable fields are defined for it:
158 * - MCS index (status->rate_idx)
159 * - HT40 (status->flag & RX_FLAG_40MHZ)
160 * - short-GI (status->flag & RX_FLAG_SHORT_GI)
161 */
162 *pos = 0;
163 } else {
164 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
165 *pos = rate->bitrate / 5;
166 }
167 pos++;
168
169 /* IEEE80211_RADIOTAP_CHANNEL */
170 *(__le16 *)pos = cpu_to_le16(status->freq);
171 pos += 2;
172 if (status->band == IEEE80211_BAND_5GHZ)
173 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
174 IEEE80211_CHAN_5GHZ);
175 else if (rate->flags & IEEE80211_RATE_ERP_G)
176 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
177 IEEE80211_CHAN_2GHZ);
178 else
179 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
180 IEEE80211_CHAN_2GHZ);
181 pos += 2;
182
183 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
184 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
185 *pos = status->signal;
186 rthdr->it_present |=
187 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
188 pos++;
189 }
190
191 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
192 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
193 *pos = status->noise;
194 rthdr->it_present |=
195 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
196 pos++;
197 }
198
199 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
200
201 /* IEEE80211_RADIOTAP_ANTENNA */
202 *pos = status->antenna;
203 pos++;
204
205 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
206
207 /* IEEE80211_RADIOTAP_RX_FLAGS */
208 /* ensure 2 byte alignment for the 2 byte field as required */
209 if ((pos - (unsigned char *)rthdr) & 1)
210 pos++;
211 if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
212 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
213 pos += 2;
214 }
215
216 /*
217 * This function copies a received frame to all monitor interfaces and
218 * returns a cleaned-up SKB that no longer includes the FCS nor the
219 * radiotap header the driver might have added.
220 */
221 static struct sk_buff *
222 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
223 struct ieee80211_rx_status *status,
224 struct ieee80211_rate *rate)
225 {
226 struct ieee80211_sub_if_data *sdata;
227 int needed_headroom = 0;
228 struct sk_buff *skb, *skb2;
229 struct net_device *prev_dev = NULL;
230 int present_fcs_len = 0;
231 int rtap_len = 0;
232
233 /*
234 * First, we may need to make a copy of the skb because
235 * (1) we need to modify it for radiotap (if not present), and
236 * (2) the other RX handlers will modify the skb we got.
237 *
238 * We don't need to, of course, if we aren't going to return
239 * the SKB because it has a bad FCS/PLCP checksum.
240 */
241 if (status->flag & RX_FLAG_RADIOTAP)
242 rtap_len = ieee80211_get_radiotap_len(origskb->data);
243 else
244 /* room for the radiotap header based on driver features */
245 needed_headroom = ieee80211_rx_radiotap_len(local, status);
246
247 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
248 present_fcs_len = FCS_LEN;
249
250 if (!local->monitors) {
251 if (should_drop_frame(status, origskb, present_fcs_len,
252 rtap_len)) {
253 dev_kfree_skb(origskb);
254 return NULL;
255 }
256
257 return remove_monitor_info(local, origskb, rtap_len);
258 }
259
260 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
261 /* only need to expand headroom if necessary */
262 skb = origskb;
263 origskb = NULL;
264
265 /*
266 * This shouldn't trigger often because most devices have an
267 * RX header they pull before we get here, and that should
268 * be big enough for our radiotap information. We should
269 * probably export the length to drivers so that we can have
270 * them allocate enough headroom to start with.
271 */
272 if (skb_headroom(skb) < needed_headroom &&
273 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
274 dev_kfree_skb(skb);
275 return NULL;
276 }
277 } else {
278 /*
279 * Need to make a copy and possibly remove radiotap header
280 * and FCS from the original.
281 */
282 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
283
284 origskb = remove_monitor_info(local, origskb, rtap_len);
285
286 if (!skb)
287 return origskb;
288 }
289
290 /* if necessary, prepend radiotap information */
291 if (!(status->flag & RX_FLAG_RADIOTAP))
292 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
293 needed_headroom);
294
295 skb_reset_mac_header(skb);
296 skb->ip_summed = CHECKSUM_UNNECESSARY;
297 skb->pkt_type = PACKET_OTHERHOST;
298 skb->protocol = htons(ETH_P_802_2);
299
300 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
301 if (!netif_running(sdata->dev))
302 continue;
303
304 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
305 continue;
306
307 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
308 continue;
309
310 if (prev_dev) {
311 skb2 = skb_clone(skb, GFP_ATOMIC);
312 if (skb2) {
313 skb2->dev = prev_dev;
314 netif_rx(skb2);
315 }
316 }
317
318 prev_dev = sdata->dev;
319 sdata->dev->stats.rx_packets++;
320 sdata->dev->stats.rx_bytes += skb->len;
321 }
322
323 if (prev_dev) {
324 skb->dev = prev_dev;
325 netif_rx(skb);
326 } else
327 dev_kfree_skb(skb);
328
329 return origskb;
330 }
331
332
333 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
334 {
335 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
336 int tid;
337
338 /* does the frame have a qos control field? */
339 if (ieee80211_is_data_qos(hdr->frame_control)) {
340 u8 *qc = ieee80211_get_qos_ctl(hdr);
341 /* frame has qos control */
342 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
343 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
344 rx->flags |= IEEE80211_RX_AMSDU;
345 else
346 rx->flags &= ~IEEE80211_RX_AMSDU;
347 } else {
348 /*
349 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
350 *
351 * Sequence numbers for management frames, QoS data
352 * frames with a broadcast/multicast address in the
353 * Address 1 field, and all non-QoS data frames sent
354 * by QoS STAs are assigned using an additional single
355 * modulo-4096 counter, [...]
356 *
357 * We also use that counter for non-QoS STAs.
358 */
359 tid = NUM_RX_DATA_QUEUES - 1;
360 }
361
362 rx->queue = tid;
363 /* Set skb->priority to 1d tag if highest order bit of TID is not set.
364 * For now, set skb->priority to 0 for other cases. */
365 rx->skb->priority = (tid > 7) ? 0 : tid;
366 }
367
368 /**
369 * DOC: Packet alignment
370 *
371 * Drivers always need to pass packets that are aligned to two-byte boundaries
372 * to the stack.
373 *
374 * Additionally, should, if possible, align the payload data in a way that
375 * guarantees that the contained IP header is aligned to a four-byte
376 * boundary. In the case of regular frames, this simply means aligning the
377 * payload to a four-byte boundary (because either the IP header is directly
378 * contained, or IV/RFC1042 headers that have a length divisible by four are
379 * in front of it).
380 *
381 * With A-MSDU frames, however, the payload data address must yield two modulo
382 * four because there are 14-byte 802.3 headers within the A-MSDU frames that
383 * push the IP header further back to a multiple of four again. Thankfully, the
384 * specs were sane enough this time around to require padding each A-MSDU
385 * subframe to a length that is a multiple of four.
386 *
387 * Padding like Atheros hardware adds which is inbetween the 802.11 header and
388 * the payload is not supported, the driver is required to move the 802.11
389 * header to be directly in front of the payload in that case.
390 */
391 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
392 {
393 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
394 int hdrlen;
395
396 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
397 return;
398 #endif
399
400 if (WARN_ONCE((unsigned long)rx->skb->data & 1,
401 "unaligned packet at 0x%p\n", rx->skb->data))
402 return;
403
404 if (!ieee80211_is_data_present(hdr->frame_control))
405 return;
406
407 hdrlen = ieee80211_hdrlen(hdr->frame_control);
408 if (rx->flags & IEEE80211_RX_AMSDU)
409 hdrlen += ETH_HLEN;
410 WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
411 "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
412 }
413
414
415 /* rx handlers */
416
417 static ieee80211_rx_result debug_noinline
418 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
419 {
420 struct ieee80211_local *local = rx->local;
421 struct sk_buff *skb = rx->skb;
422
423 if (unlikely(local->hw_scanning))
424 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
425
426 if (unlikely(local->sw_scanning)) {
427 /* drop all the other packets during a software scan anyway */
428 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
429 != RX_QUEUED)
430 dev_kfree_skb(skb);
431 return RX_QUEUED;
432 }
433
434 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
435 /* scanning finished during invoking of handlers */
436 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
437 return RX_DROP_UNUSABLE;
438 }
439
440 return RX_CONTINUE;
441 }
442
443
444 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
445 {
446 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
447
448 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
449 return 0;
450
451 return ieee80211_is_robust_mgmt_frame(hdr);
452 }
453
454
455 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
456 {
457 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
458
459 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
460 return 0;
461
462 return ieee80211_is_robust_mgmt_frame(hdr);
463 }
464
465
466 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
467 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
468 {
469 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
470 struct ieee80211_mmie *mmie;
471
472 if (skb->len < 24 + sizeof(*mmie) ||
473 !is_multicast_ether_addr(hdr->da))
474 return -1;
475
476 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
477 return -1; /* not a robust management frame */
478
479 mmie = (struct ieee80211_mmie *)
480 (skb->data + skb->len - sizeof(*mmie));
481 if (mmie->element_id != WLAN_EID_MMIE ||
482 mmie->length != sizeof(*mmie) - 2)
483 return -1;
484
485 return le16_to_cpu(mmie->key_id);
486 }
487
488
489 static ieee80211_rx_result
490 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
491 {
492 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
493 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
494
495 if (ieee80211_is_data(hdr->frame_control)) {
496 if (!ieee80211_has_a4(hdr->frame_control))
497 return RX_DROP_MONITOR;
498 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
499 return RX_DROP_MONITOR;
500 }
501
502 /* If there is not an established peer link and this is not a peer link
503 * establisment frame, beacon or probe, drop the frame.
504 */
505
506 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
507 struct ieee80211_mgmt *mgmt;
508
509 if (!ieee80211_is_mgmt(hdr->frame_control))
510 return RX_DROP_MONITOR;
511
512 if (ieee80211_is_action(hdr->frame_control)) {
513 mgmt = (struct ieee80211_mgmt *)hdr;
514 if (mgmt->u.action.category != PLINK_CATEGORY)
515 return RX_DROP_MONITOR;
516 return RX_CONTINUE;
517 }
518
519 if (ieee80211_is_probe_req(hdr->frame_control) ||
520 ieee80211_is_probe_resp(hdr->frame_control) ||
521 ieee80211_is_beacon(hdr->frame_control))
522 return RX_CONTINUE;
523
524 return RX_DROP_MONITOR;
525
526 }
527
528 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
529
530 if (ieee80211_is_data(hdr->frame_control) &&
531 is_multicast_ether_addr(hdr->addr1) &&
532 mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
533 return RX_DROP_MONITOR;
534 #undef msh_h_get
535
536 return RX_CONTINUE;
537 }
538
539
540 static ieee80211_rx_result debug_noinline
541 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
542 {
543 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
544
545 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
546 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
547 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
548 rx->sta->last_seq_ctrl[rx->queue] ==
549 hdr->seq_ctrl)) {
550 if (rx->flags & IEEE80211_RX_RA_MATCH) {
551 rx->local->dot11FrameDuplicateCount++;
552 rx->sta->num_duplicates++;
553 }
554 return RX_DROP_MONITOR;
555 } else
556 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
557 }
558
559 if (unlikely(rx->skb->len < 16)) {
560 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
561 return RX_DROP_MONITOR;
562 }
563
564 /* Drop disallowed frame classes based on STA auth/assoc state;
565 * IEEE 802.11, Chap 5.5.
566 *
567 * mac80211 filters only based on association state, i.e. it drops
568 * Class 3 frames from not associated stations. hostapd sends
569 * deauth/disassoc frames when needed. In addition, hostapd is
570 * responsible for filtering on both auth and assoc states.
571 */
572
573 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
574 return ieee80211_rx_mesh_check(rx);
575
576 if (unlikely((ieee80211_is_data(hdr->frame_control) ||
577 ieee80211_is_pspoll(hdr->frame_control)) &&
578 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
579 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
580 if ((!ieee80211_has_fromds(hdr->frame_control) &&
581 !ieee80211_has_tods(hdr->frame_control) &&
582 ieee80211_is_data(hdr->frame_control)) ||
583 !(rx->flags & IEEE80211_RX_RA_MATCH)) {
584 /* Drop IBSS frames and frames for other hosts
585 * silently. */
586 return RX_DROP_MONITOR;
587 }
588
589 return RX_DROP_MONITOR;
590 }
591
592 return RX_CONTINUE;
593 }
594
595
596 static ieee80211_rx_result debug_noinline
597 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
598 {
599 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
600 int keyidx;
601 int hdrlen;
602 ieee80211_rx_result result = RX_DROP_UNUSABLE;
603 struct ieee80211_key *stakey = NULL;
604 int mmie_keyidx = -1;
605
606 /*
607 * Key selection 101
608 *
609 * There are four types of keys:
610 * - GTK (group keys)
611 * - IGTK (group keys for management frames)
612 * - PTK (pairwise keys)
613 * - STK (station-to-station pairwise keys)
614 *
615 * When selecting a key, we have to distinguish between multicast
616 * (including broadcast) and unicast frames, the latter can only
617 * use PTKs and STKs while the former always use GTKs and IGTKs.
618 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
619 * unicast frames can also use key indices like GTKs. Hence, if we
620 * don't have a PTK/STK we check the key index for a WEP key.
621 *
622 * Note that in a regular BSS, multicast frames are sent by the
623 * AP only, associated stations unicast the frame to the AP first
624 * which then multicasts it on their behalf.
625 *
626 * There is also a slight problem in IBSS mode: GTKs are negotiated
627 * with each station, that is something we don't currently handle.
628 * The spec seems to expect that one negotiates the same key with
629 * every station but there's no such requirement; VLANs could be
630 * possible.
631 */
632
633 /*
634 * No point in finding a key and decrypting if the frame is neither
635 * addressed to us nor a multicast frame.
636 */
637 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
638 return RX_CONTINUE;
639
640 if (rx->sta)
641 stakey = rcu_dereference(rx->sta->key);
642
643 if (!ieee80211_has_protected(hdr->frame_control))
644 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
645
646 if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
647 rx->key = stakey;
648 /* Skip decryption if the frame is not protected. */
649 if (!ieee80211_has_protected(hdr->frame_control))
650 return RX_CONTINUE;
651 } else if (mmie_keyidx >= 0) {
652 /* Broadcast/multicast robust management frame / BIP */
653 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
654 (rx->status->flag & RX_FLAG_IV_STRIPPED))
655 return RX_CONTINUE;
656
657 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
658 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
659 return RX_DROP_MONITOR; /* unexpected BIP keyidx */
660 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
661 } else if (!ieee80211_has_protected(hdr->frame_control)) {
662 /*
663 * The frame was not protected, so skip decryption. However, we
664 * need to set rx->key if there is a key that could have been
665 * used so that the frame may be dropped if encryption would
666 * have been expected.
667 */
668 struct ieee80211_key *key = NULL;
669 if (ieee80211_is_mgmt(hdr->frame_control) &&
670 is_multicast_ether_addr(hdr->addr1) &&
671 (key = rcu_dereference(rx->sdata->default_mgmt_key)))
672 rx->key = key;
673 else if ((key = rcu_dereference(rx->sdata->default_key)))
674 rx->key = key;
675 return RX_CONTINUE;
676 } else {
677 /*
678 * The device doesn't give us the IV so we won't be
679 * able to look up the key. That's ok though, we
680 * don't need to decrypt the frame, we just won't
681 * be able to keep statistics accurate.
682 * Except for key threshold notifications, should
683 * we somehow allow the driver to tell us which key
684 * the hardware used if this flag is set?
685 */
686 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
687 (rx->status->flag & RX_FLAG_IV_STRIPPED))
688 return RX_CONTINUE;
689
690 hdrlen = ieee80211_hdrlen(hdr->frame_control);
691
692 if (rx->skb->len < 8 + hdrlen)
693 return RX_DROP_UNUSABLE; /* TODO: count this? */
694
695 /*
696 * no need to call ieee80211_wep_get_keyidx,
697 * it verifies a bunch of things we've done already
698 */
699 keyidx = rx->skb->data[hdrlen + 3] >> 6;
700
701 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
702
703 /*
704 * RSNA-protected unicast frames should always be sent with
705 * pairwise or station-to-station keys, but for WEP we allow
706 * using a key index as well.
707 */
708 if (rx->key && rx->key->conf.alg != ALG_WEP &&
709 !is_multicast_ether_addr(hdr->addr1))
710 rx->key = NULL;
711 }
712
713 if (rx->key) {
714 rx->key->tx_rx_count++;
715 /* TODO: add threshold stuff again */
716 } else {
717 return RX_DROP_MONITOR;
718 }
719
720 /* Check for weak IVs if possible */
721 if (rx->sta && rx->key->conf.alg == ALG_WEP &&
722 ieee80211_is_data(hdr->frame_control) &&
723 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
724 !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
725 ieee80211_wep_is_weak_iv(rx->skb, rx->key))
726 rx->sta->wep_weak_iv_count++;
727
728 switch (rx->key->conf.alg) {
729 case ALG_WEP:
730 result = ieee80211_crypto_wep_decrypt(rx);
731 break;
732 case ALG_TKIP:
733 result = ieee80211_crypto_tkip_decrypt(rx);
734 break;
735 case ALG_CCMP:
736 result = ieee80211_crypto_ccmp_decrypt(rx);
737 break;
738 case ALG_AES_CMAC:
739 result = ieee80211_crypto_aes_cmac_decrypt(rx);
740 break;
741 }
742
743 /* either the frame has been decrypted or will be dropped */
744 rx->status->flag |= RX_FLAG_DECRYPTED;
745
746 return result;
747 }
748
749 static ieee80211_rx_result debug_noinline
750 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
751 {
752 struct ieee80211_local *local;
753 struct ieee80211_hdr *hdr;
754 struct sk_buff *skb;
755
756 local = rx->local;
757 skb = rx->skb;
758 hdr = (struct ieee80211_hdr *) skb->data;
759
760 if (!local->pspolling)
761 return RX_CONTINUE;
762
763 if (!ieee80211_has_fromds(hdr->frame_control))
764 /* this is not from AP */
765 return RX_CONTINUE;
766
767 if (!ieee80211_is_data(hdr->frame_control))
768 return RX_CONTINUE;
769
770 if (!ieee80211_has_moredata(hdr->frame_control)) {
771 /* AP has no more frames buffered for us */
772 local->pspolling = false;
773 return RX_CONTINUE;
774 }
775
776 /* more data bit is set, let's request a new frame from the AP */
777 ieee80211_send_pspoll(local, rx->sdata);
778
779 return RX_CONTINUE;
780 }
781
782 static void ap_sta_ps_start(struct sta_info *sta)
783 {
784 struct ieee80211_sub_if_data *sdata = sta->sdata;
785 struct ieee80211_local *local = sdata->local;
786
787 atomic_inc(&sdata->bss->num_sta_ps);
788 set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
789 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
790 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
791 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
792 sdata->dev->name, sta->sta.addr, sta->sta.aid);
793 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
794 }
795
796 static int ap_sta_ps_end(struct sta_info *sta)
797 {
798 struct ieee80211_sub_if_data *sdata = sta->sdata;
799 struct ieee80211_local *local = sdata->local;
800 struct sk_buff *skb;
801 int sent = 0;
802
803 atomic_dec(&sdata->bss->num_sta_ps);
804
805 clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
806 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
807
808 if (!skb_queue_empty(&sta->ps_tx_buf))
809 sta_info_clear_tim_bit(sta);
810
811 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
812 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
813 sdata->dev->name, sta->sta.addr, sta->sta.aid);
814 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
815
816 /* Send all buffered frames to the station */
817 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
818 sent++;
819 skb->requeue = 1;
820 dev_queue_xmit(skb);
821 }
822 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
823 local->total_ps_buffered--;
824 sent++;
825 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
826 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
827 "since STA not sleeping anymore\n", sdata->dev->name,
828 sta->sta.addr, sta->sta.aid);
829 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
830 skb->requeue = 1;
831 dev_queue_xmit(skb);
832 }
833
834 return sent;
835 }
836
837 static ieee80211_rx_result debug_noinline
838 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
839 {
840 struct sta_info *sta = rx->sta;
841 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
842
843 if (!sta)
844 return RX_CONTINUE;
845
846 /* Update last_rx only for IBSS packets which are for the current
847 * BSSID to avoid keeping the current IBSS network alive in cases where
848 * other STAs are using different BSSID. */
849 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
850 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
851 NL80211_IFTYPE_ADHOC);
852 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
853 sta->last_rx = jiffies;
854 } else
855 if (!is_multicast_ether_addr(hdr->addr1) ||
856 rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
857 /* Update last_rx only for unicast frames in order to prevent
858 * the Probe Request frames (the only broadcast frames from a
859 * STA in infrastructure mode) from keeping a connection alive.
860 * Mesh beacons will update last_rx when if they are found to
861 * match the current local configuration when processed.
862 */
863 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
864 ieee80211_is_beacon(hdr->frame_control)) {
865 rx->sdata->u.mgd.last_beacon = jiffies;
866 } else
867 sta->last_rx = jiffies;
868 }
869
870 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
871 return RX_CONTINUE;
872
873 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
874 ieee80211_sta_rx_notify(rx->sdata, hdr);
875
876 sta->rx_fragments++;
877 sta->rx_bytes += rx->skb->len;
878 sta->last_signal = rx->status->signal;
879 sta->last_qual = rx->status->qual;
880 sta->last_noise = rx->status->noise;
881
882 /*
883 * Change STA power saving mode only at the end of a frame
884 * exchange sequence.
885 */
886 if (!ieee80211_has_morefrags(hdr->frame_control) &&
887 (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
888 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
889 if (test_sta_flags(sta, WLAN_STA_PS)) {
890 /*
891 * Ignore doze->wake transitions that are
892 * indicated by non-data frames, the standard
893 * is unclear here, but for example going to
894 * PS mode and then scanning would cause a
895 * doze->wake transition for the probe request,
896 * and that is clearly undesirable.
897 */
898 if (ieee80211_is_data(hdr->frame_control) &&
899 !ieee80211_has_pm(hdr->frame_control))
900 rx->sent_ps_buffered += ap_sta_ps_end(sta);
901 } else {
902 if (ieee80211_has_pm(hdr->frame_control))
903 ap_sta_ps_start(sta);
904 }
905 }
906
907 /* Drop data::nullfunc frames silently, since they are used only to
908 * control station power saving mode. */
909 if (ieee80211_is_nullfunc(hdr->frame_control)) {
910 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
911 /* Update counter and free packet here to avoid counting this
912 * as a dropped packed. */
913 sta->rx_packets++;
914 dev_kfree_skb(rx->skb);
915 return RX_QUEUED;
916 }
917
918 return RX_CONTINUE;
919 } /* ieee80211_rx_h_sta_process */
920
921 static inline struct ieee80211_fragment_entry *
922 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
923 unsigned int frag, unsigned int seq, int rx_queue,
924 struct sk_buff **skb)
925 {
926 struct ieee80211_fragment_entry *entry;
927 int idx;
928
929 idx = sdata->fragment_next;
930 entry = &sdata->fragments[sdata->fragment_next++];
931 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
932 sdata->fragment_next = 0;
933
934 if (!skb_queue_empty(&entry->skb_list)) {
935 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
936 struct ieee80211_hdr *hdr =
937 (struct ieee80211_hdr *) entry->skb_list.next->data;
938 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
939 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
940 "addr1=%pM addr2=%pM\n",
941 sdata->dev->name, idx,
942 jiffies - entry->first_frag_time, entry->seq,
943 entry->last_frag, hdr->addr1, hdr->addr2);
944 #endif
945 __skb_queue_purge(&entry->skb_list);
946 }
947
948 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
949 *skb = NULL;
950 entry->first_frag_time = jiffies;
951 entry->seq = seq;
952 entry->rx_queue = rx_queue;
953 entry->last_frag = frag;
954 entry->ccmp = 0;
955 entry->extra_len = 0;
956
957 return entry;
958 }
959
960 static inline struct ieee80211_fragment_entry *
961 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
962 unsigned int frag, unsigned int seq,
963 int rx_queue, struct ieee80211_hdr *hdr)
964 {
965 struct ieee80211_fragment_entry *entry;
966 int i, idx;
967
968 idx = sdata->fragment_next;
969 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
970 struct ieee80211_hdr *f_hdr;
971
972 idx--;
973 if (idx < 0)
974 idx = IEEE80211_FRAGMENT_MAX - 1;
975
976 entry = &sdata->fragments[idx];
977 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
978 entry->rx_queue != rx_queue ||
979 entry->last_frag + 1 != frag)
980 continue;
981
982 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
983
984 /*
985 * Check ftype and addresses are equal, else check next fragment
986 */
987 if (((hdr->frame_control ^ f_hdr->frame_control) &
988 cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
989 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
990 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
991 continue;
992
993 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
994 __skb_queue_purge(&entry->skb_list);
995 continue;
996 }
997 return entry;
998 }
999
1000 return NULL;
1001 }
1002
1003 static ieee80211_rx_result debug_noinline
1004 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1005 {
1006 struct ieee80211_hdr *hdr;
1007 u16 sc;
1008 __le16 fc;
1009 unsigned int frag, seq;
1010 struct ieee80211_fragment_entry *entry;
1011 struct sk_buff *skb;
1012
1013 hdr = (struct ieee80211_hdr *)rx->skb->data;
1014 fc = hdr->frame_control;
1015 sc = le16_to_cpu(hdr->seq_ctrl);
1016 frag = sc & IEEE80211_SCTL_FRAG;
1017
1018 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1019 (rx->skb)->len < 24 ||
1020 is_multicast_ether_addr(hdr->addr1))) {
1021 /* not fragmented */
1022 goto out;
1023 }
1024 I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1025
1026 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1027
1028 if (frag == 0) {
1029 /* This is the first fragment of a new frame. */
1030 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1031 rx->queue, &(rx->skb));
1032 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1033 ieee80211_has_protected(fc)) {
1034 /* Store CCMP PN so that we can verify that the next
1035 * fragment has a sequential PN value. */
1036 entry->ccmp = 1;
1037 memcpy(entry->last_pn,
1038 rx->key->u.ccmp.rx_pn[rx->queue],
1039 CCMP_PN_LEN);
1040 }
1041 return RX_QUEUED;
1042 }
1043
1044 /* This is a fragment for a frame that should already be pending in
1045 * fragment cache. Add this fragment to the end of the pending entry.
1046 */
1047 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1048 if (!entry) {
1049 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1050 return RX_DROP_MONITOR;
1051 }
1052
1053 /* Verify that MPDUs within one MSDU have sequential PN values.
1054 * (IEEE 802.11i, 8.3.3.4.5) */
1055 if (entry->ccmp) {
1056 int i;
1057 u8 pn[CCMP_PN_LEN], *rpn;
1058 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1059 return RX_DROP_UNUSABLE;
1060 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1061 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1062 pn[i]++;
1063 if (pn[i])
1064 break;
1065 }
1066 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1067 if (memcmp(pn, rpn, CCMP_PN_LEN))
1068 return RX_DROP_UNUSABLE;
1069 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1070 }
1071
1072 skb_pull(rx->skb, ieee80211_hdrlen(fc));
1073 __skb_queue_tail(&entry->skb_list, rx->skb);
1074 entry->last_frag = frag;
1075 entry->extra_len += rx->skb->len;
1076 if (ieee80211_has_morefrags(fc)) {
1077 rx->skb = NULL;
1078 return RX_QUEUED;
1079 }
1080
1081 rx->skb = __skb_dequeue(&entry->skb_list);
1082 if (skb_tailroom(rx->skb) < entry->extra_len) {
1083 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1084 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1085 GFP_ATOMIC))) {
1086 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1087 __skb_queue_purge(&entry->skb_list);
1088 return RX_DROP_UNUSABLE;
1089 }
1090 }
1091 while ((skb = __skb_dequeue(&entry->skb_list))) {
1092 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1093 dev_kfree_skb(skb);
1094 }
1095
1096 /* Complete frame has been reassembled - process it now */
1097 rx->flags |= IEEE80211_RX_FRAGMENTED;
1098
1099 out:
1100 if (rx->sta)
1101 rx->sta->rx_packets++;
1102 if (is_multicast_ether_addr(hdr->addr1))
1103 rx->local->dot11MulticastReceivedFrameCount++;
1104 else
1105 ieee80211_led_rx(rx->local);
1106 return RX_CONTINUE;
1107 }
1108
1109 static ieee80211_rx_result debug_noinline
1110 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1111 {
1112 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1113 struct sk_buff *skb;
1114 int no_pending_pkts;
1115 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1116
1117 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1118 !(rx->flags & IEEE80211_RX_RA_MATCH)))
1119 return RX_CONTINUE;
1120
1121 if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1122 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1123 return RX_DROP_UNUSABLE;
1124
1125 skb = skb_dequeue(&rx->sta->tx_filtered);
1126 if (!skb) {
1127 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1128 if (skb)
1129 rx->local->total_ps_buffered--;
1130 }
1131 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1132 skb_queue_empty(&rx->sta->ps_tx_buf);
1133
1134 if (skb) {
1135 struct ieee80211_hdr *hdr =
1136 (struct ieee80211_hdr *) skb->data;
1137
1138 /*
1139 * Tell TX path to send one frame even though the STA may
1140 * still remain is PS mode after this frame exchange.
1141 */
1142 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1143
1144 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1145 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1146 rx->sta->sta.addr, rx->sta->sta.aid,
1147 skb_queue_len(&rx->sta->ps_tx_buf));
1148 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1149
1150 /* Use MoreData flag to indicate whether there are more
1151 * buffered frames for this STA */
1152 if (no_pending_pkts)
1153 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1154 else
1155 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1156
1157 dev_queue_xmit(skb);
1158
1159 if (no_pending_pkts)
1160 sta_info_clear_tim_bit(rx->sta);
1161 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1162 } else if (!rx->sent_ps_buffered) {
1163 /*
1164 * FIXME: This can be the result of a race condition between
1165 * us expiring a frame and the station polling for it.
1166 * Should we send it a null-func frame indicating we
1167 * have nothing buffered for it?
1168 */
1169 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1170 "though there are no buffered frames for it\n",
1171 rx->dev->name, rx->sta->sta.addr);
1172 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1173 }
1174
1175 /* Free PS Poll skb here instead of returning RX_DROP that would
1176 * count as an dropped frame. */
1177 dev_kfree_skb(rx->skb);
1178
1179 return RX_QUEUED;
1180 }
1181
1182 static ieee80211_rx_result debug_noinline
1183 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1184 {
1185 u8 *data = rx->skb->data;
1186 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1187
1188 if (!ieee80211_is_data_qos(hdr->frame_control))
1189 return RX_CONTINUE;
1190
1191 /* remove the qos control field, update frame type and meta-data */
1192 memmove(data + IEEE80211_QOS_CTL_LEN, data,
1193 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1194 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1195 /* change frame type to non QOS */
1196 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1197
1198 return RX_CONTINUE;
1199 }
1200
1201 static int
1202 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1203 {
1204 if (unlikely(!rx->sta ||
1205 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1206 return -EACCES;
1207
1208 return 0;
1209 }
1210
1211 static int
1212 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1213 {
1214 /*
1215 * Pass through unencrypted frames if the hardware has
1216 * decrypted them already.
1217 */
1218 if (rx->status->flag & RX_FLAG_DECRYPTED)
1219 return 0;
1220
1221 /* Drop unencrypted frames if key is set. */
1222 if (unlikely(!ieee80211_has_protected(fc) &&
1223 !ieee80211_is_nullfunc(fc) &&
1224 ieee80211_is_data(fc) &&
1225 (rx->key || rx->sdata->drop_unencrypted)))
1226 return -EACCES;
1227 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1228 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1229 rx->key))
1230 return -EACCES;
1231 /* BIP does not use Protected field, so need to check MMIE */
1232 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
1233 && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1234 rx->key))
1235 return -EACCES;
1236 /*
1237 * When using MFP, Action frames are not allowed prior to
1238 * having configured keys.
1239 */
1240 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1241 ieee80211_is_robust_mgmt_frame(
1242 (struct ieee80211_hdr *) rx->skb->data)))
1243 return -EACCES;
1244 }
1245
1246 return 0;
1247 }
1248
1249 static int
1250 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1251 {
1252 struct net_device *dev = rx->dev;
1253 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1254 u16 hdrlen, ethertype;
1255 u8 *payload;
1256 u8 dst[ETH_ALEN];
1257 u8 src[ETH_ALEN] __aligned(2);
1258 struct sk_buff *skb = rx->skb;
1259 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1260
1261 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1262 return -1;
1263
1264 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1265
1266 /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1267 * header
1268 * IEEE 802.11 address fields:
1269 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1270 * 0 0 DA SA BSSID n/a
1271 * 0 1 DA BSSID SA n/a
1272 * 1 0 BSSID SA DA n/a
1273 * 1 1 RA TA DA SA
1274 */
1275 memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1276 memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1277
1278 switch (hdr->frame_control &
1279 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1280 case cpu_to_le16(IEEE80211_FCTL_TODS):
1281 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1282 sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1283 return -1;
1284 break;
1285 case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1286 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1287 sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1288 return -1;
1289 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1290 struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1291 (skb->data + hdrlen);
1292 hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1293 if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1294 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1295 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1296 }
1297 }
1298 break;
1299 case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1300 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1301 (is_multicast_ether_addr(dst) &&
1302 !compare_ether_addr(src, dev->dev_addr)))
1303 return -1;
1304 break;
1305 case cpu_to_le16(0):
1306 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1307 return -1;
1308 break;
1309 }
1310
1311 if (unlikely(skb->len - hdrlen < 8))
1312 return -1;
1313
1314 payload = skb->data + hdrlen;
1315 ethertype = (payload[6] << 8) | payload[7];
1316
1317 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1318 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1319 compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1320 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1321 * replace EtherType */
1322 skb_pull(skb, hdrlen + 6);
1323 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1324 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1325 } else {
1326 struct ethhdr *ehdr;
1327 __be16 len;
1328
1329 skb_pull(skb, hdrlen);
1330 len = htons(skb->len);
1331 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1332 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1333 memcpy(ehdr->h_source, src, ETH_ALEN);
1334 ehdr->h_proto = len;
1335 }
1336 return 0;
1337 }
1338
1339 /*
1340 * requires that rx->skb is a frame with ethernet header
1341 */
1342 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1343 {
1344 static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1345 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1346 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1347
1348 /*
1349 * Allow EAPOL frames to us/the PAE group address regardless
1350 * of whether the frame was encrypted or not.
1351 */
1352 if (ehdr->h_proto == htons(ETH_P_PAE) &&
1353 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1354 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1355 return true;
1356
1357 if (ieee80211_802_1x_port_control(rx) ||
1358 ieee80211_drop_unencrypted(rx, fc))
1359 return false;
1360
1361 return true;
1362 }
1363
1364 /*
1365 * requires that rx->skb is a frame with ethernet header
1366 */
1367 static void
1368 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1369 {
1370 struct net_device *dev = rx->dev;
1371 struct ieee80211_local *local = rx->local;
1372 struct sk_buff *skb, *xmit_skb;
1373 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1374 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1375 struct sta_info *dsta;
1376
1377 skb = rx->skb;
1378 xmit_skb = NULL;
1379
1380 if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1381 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1382 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1383 (rx->flags & IEEE80211_RX_RA_MATCH)) {
1384 if (is_multicast_ether_addr(ehdr->h_dest)) {
1385 /*
1386 * send multicast frames both to higher layers in
1387 * local net stack and back to the wireless medium
1388 */
1389 xmit_skb = skb_copy(skb, GFP_ATOMIC);
1390 if (!xmit_skb && net_ratelimit())
1391 printk(KERN_DEBUG "%s: failed to clone "
1392 "multicast frame\n", dev->name);
1393 } else {
1394 dsta = sta_info_get(local, skb->data);
1395 if (dsta && dsta->sdata->dev == dev) {
1396 /*
1397 * The destination station is associated to
1398 * this AP (in this VLAN), so send the frame
1399 * directly to it and do not pass it to local
1400 * net stack.
1401 */
1402 xmit_skb = skb;
1403 skb = NULL;
1404 }
1405 }
1406 }
1407
1408 if (skb) {
1409 int align __maybe_unused;
1410
1411 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1412 /*
1413 * 'align' will only take the values 0 or 2 here
1414 * since all frames are required to be aligned
1415 * to 2-byte boundaries when being passed to
1416 * mac80211. That also explains the __skb_push()
1417 * below.
1418 */
1419 align = (unsigned long)skb->data & 3;
1420 if (align) {
1421 if (WARN_ON(skb_headroom(skb) < 3)) {
1422 dev_kfree_skb(skb);
1423 skb = NULL;
1424 } else {
1425 u8 *data = skb->data;
1426 size_t len = skb->len;
1427 u8 *new = __skb_push(skb, align);
1428 memmove(new, data, len);
1429 __skb_trim(skb, len);
1430 }
1431 }
1432 #endif
1433
1434 if (skb) {
1435 /* deliver to local stack */
1436 skb->protocol = eth_type_trans(skb, dev);
1437 memset(skb->cb, 0, sizeof(skb->cb));
1438 netif_rx(skb);
1439 }
1440 }
1441
1442 if (xmit_skb) {
1443 /* send to wireless media */
1444 xmit_skb->protocol = htons(ETH_P_802_3);
1445 skb_reset_network_header(xmit_skb);
1446 skb_reset_mac_header(xmit_skb);
1447 dev_queue_xmit(xmit_skb);
1448 }
1449 }
1450
1451 static ieee80211_rx_result debug_noinline
1452 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1453 {
1454 struct net_device *dev = rx->dev;
1455 struct ieee80211_local *local = rx->local;
1456 u16 ethertype;
1457 u8 *payload;
1458 struct sk_buff *skb = rx->skb, *frame = NULL;
1459 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1460 __le16 fc = hdr->frame_control;
1461 const struct ethhdr *eth;
1462 int remaining, err;
1463 u8 dst[ETH_ALEN];
1464 u8 src[ETH_ALEN];
1465
1466 if (unlikely(!ieee80211_is_data(fc)))
1467 return RX_CONTINUE;
1468
1469 if (unlikely(!ieee80211_is_data_present(fc)))
1470 return RX_DROP_MONITOR;
1471
1472 if (!(rx->flags & IEEE80211_RX_AMSDU))
1473 return RX_CONTINUE;
1474
1475 err = ieee80211_data_to_8023(rx);
1476 if (unlikely(err))
1477 return RX_DROP_UNUSABLE;
1478
1479 skb->dev = dev;
1480
1481 dev->stats.rx_packets++;
1482 dev->stats.rx_bytes += skb->len;
1483
1484 /* skip the wrapping header */
1485 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1486 if (!eth)
1487 return RX_DROP_UNUSABLE;
1488
1489 while (skb != frame) {
1490 u8 padding;
1491 __be16 len = eth->h_proto;
1492 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1493
1494 remaining = skb->len;
1495 memcpy(dst, eth->h_dest, ETH_ALEN);
1496 memcpy(src, eth->h_source, ETH_ALEN);
1497
1498 padding = ((4 - subframe_len) & 0x3);
1499 /* the last MSDU has no padding */
1500 if (subframe_len > remaining)
1501 return RX_DROP_UNUSABLE;
1502
1503 skb_pull(skb, sizeof(struct ethhdr));
1504 /* if last subframe reuse skb */
1505 if (remaining <= subframe_len + padding)
1506 frame = skb;
1507 else {
1508 /*
1509 * Allocate and reserve two bytes more for payload
1510 * alignment since sizeof(struct ethhdr) is 14.
1511 */
1512 frame = dev_alloc_skb(
1513 ALIGN(local->hw.extra_tx_headroom, 4) +
1514 subframe_len + 2);
1515
1516 if (frame == NULL)
1517 return RX_DROP_UNUSABLE;
1518
1519 skb_reserve(frame,
1520 ALIGN(local->hw.extra_tx_headroom, 4) +
1521 sizeof(struct ethhdr) + 2);
1522 memcpy(skb_put(frame, ntohs(len)), skb->data,
1523 ntohs(len));
1524
1525 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1526 padding);
1527 if (!eth) {
1528 dev_kfree_skb(frame);
1529 return RX_DROP_UNUSABLE;
1530 }
1531 }
1532
1533 skb_reset_network_header(frame);
1534 frame->dev = dev;
1535 frame->priority = skb->priority;
1536 rx->skb = frame;
1537
1538 payload = frame->data;
1539 ethertype = (payload[6] << 8) | payload[7];
1540
1541 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1542 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1543 compare_ether_addr(payload,
1544 bridge_tunnel_header) == 0)) {
1545 /* remove RFC1042 or Bridge-Tunnel
1546 * encapsulation and replace EtherType */
1547 skb_pull(frame, 6);
1548 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1549 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1550 } else {
1551 memcpy(skb_push(frame, sizeof(__be16)),
1552 &len, sizeof(__be16));
1553 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1554 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1555 }
1556
1557 if (!ieee80211_frame_allowed(rx, fc)) {
1558 if (skb == frame) /* last frame */
1559 return RX_DROP_UNUSABLE;
1560 dev_kfree_skb(frame);
1561 continue;
1562 }
1563
1564 ieee80211_deliver_skb(rx);
1565 }
1566
1567 return RX_QUEUED;
1568 }
1569
1570 #ifdef CONFIG_MAC80211_MESH
1571 static ieee80211_rx_result
1572 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1573 {
1574 struct ieee80211_hdr *hdr;
1575 struct ieee80211s_hdr *mesh_hdr;
1576 unsigned int hdrlen;
1577 struct sk_buff *skb = rx->skb, *fwd_skb;
1578
1579 hdr = (struct ieee80211_hdr *) skb->data;
1580 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1581 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1582
1583 if (!ieee80211_is_data(hdr->frame_control))
1584 return RX_CONTINUE;
1585
1586 if (!mesh_hdr->ttl)
1587 /* illegal frame */
1588 return RX_DROP_MONITOR;
1589
1590 if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1591 struct ieee80211_sub_if_data *sdata;
1592 struct mesh_path *mppath;
1593
1594 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1595 rcu_read_lock();
1596 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1597 if (!mppath) {
1598 mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1599 } else {
1600 spin_lock_bh(&mppath->state_lock);
1601 mppath->exp_time = jiffies;
1602 if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1603 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1604 spin_unlock_bh(&mppath->state_lock);
1605 }
1606 rcu_read_unlock();
1607 }
1608
1609 if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1610 return RX_CONTINUE;
1611
1612 mesh_hdr->ttl--;
1613
1614 if (rx->flags & IEEE80211_RX_RA_MATCH) {
1615 if (!mesh_hdr->ttl)
1616 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1617 dropped_frames_ttl);
1618 else {
1619 struct ieee80211_hdr *fwd_hdr;
1620 fwd_skb = skb_copy(skb, GFP_ATOMIC);
1621
1622 if (!fwd_skb && net_ratelimit())
1623 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1624 rx->dev->name);
1625
1626 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
1627 /*
1628 * Save TA to addr1 to send TA a path error if a
1629 * suitable next hop is not found
1630 */
1631 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1632 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1633 fwd_skb->dev = rx->local->mdev;
1634 fwd_skb->iif = rx->dev->ifindex;
1635 dev_queue_xmit(fwd_skb);
1636 }
1637 }
1638
1639 if (is_multicast_ether_addr(hdr->addr3) ||
1640 rx->dev->flags & IFF_PROMISC)
1641 return RX_CONTINUE;
1642 else
1643 return RX_DROP_MONITOR;
1644 }
1645 #endif
1646
1647 static ieee80211_rx_result debug_noinline
1648 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1649 {
1650 struct net_device *dev = rx->dev;
1651 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1652 __le16 fc = hdr->frame_control;
1653 int err;
1654
1655 if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1656 return RX_CONTINUE;
1657
1658 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1659 return RX_DROP_MONITOR;
1660
1661 err = ieee80211_data_to_8023(rx);
1662 if (unlikely(err))
1663 return RX_DROP_UNUSABLE;
1664
1665 if (!ieee80211_frame_allowed(rx, fc))
1666 return RX_DROP_MONITOR;
1667
1668 rx->skb->dev = dev;
1669
1670 dev->stats.rx_packets++;
1671 dev->stats.rx_bytes += rx->skb->len;
1672
1673 ieee80211_deliver_skb(rx);
1674
1675 return RX_QUEUED;
1676 }
1677
1678 static ieee80211_rx_result debug_noinline
1679 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1680 {
1681 struct ieee80211_local *local = rx->local;
1682 struct ieee80211_hw *hw = &local->hw;
1683 struct sk_buff *skb = rx->skb;
1684 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1685 struct tid_ampdu_rx *tid_agg_rx;
1686 u16 start_seq_num;
1687 u16 tid;
1688
1689 if (likely(!ieee80211_is_ctl(bar->frame_control)))
1690 return RX_CONTINUE;
1691
1692 if (ieee80211_is_back_req(bar->frame_control)) {
1693 if (!rx->sta)
1694 return RX_CONTINUE;
1695 tid = le16_to_cpu(bar->control) >> 12;
1696 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1697 != HT_AGG_STATE_OPERATIONAL)
1698 return RX_CONTINUE;
1699 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1700
1701 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1702
1703 /* reset session timer */
1704 if (tid_agg_rx->timeout)
1705 mod_timer(&tid_agg_rx->session_timer,
1706 TU_TO_EXP_TIME(tid_agg_rx->timeout));
1707
1708 /* manage reordering buffer according to requested */
1709 /* sequence number */
1710 rcu_read_lock();
1711 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, NULL,
1712 start_seq_num, 1);
1713 rcu_read_unlock();
1714 return RX_DROP_UNUSABLE;
1715 }
1716
1717 return RX_CONTINUE;
1718 }
1719
1720 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1721 struct ieee80211_mgmt *mgmt,
1722 size_t len)
1723 {
1724 struct ieee80211_local *local = sdata->local;
1725 struct sk_buff *skb;
1726 struct ieee80211_mgmt *resp;
1727
1728 if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1729 /* Not to own unicast address */
1730 return;
1731 }
1732
1733 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1734 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1735 /* Not from the current AP. */
1736 return;
1737 }
1738
1739 if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1740 /* Association in progress; ignore SA Query */
1741 return;
1742 }
1743
1744 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1745 /* Too short SA Query request frame */
1746 return;
1747 }
1748
1749 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1750 if (skb == NULL)
1751 return;
1752
1753 skb_reserve(skb, local->hw.extra_tx_headroom);
1754 resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1755 memset(resp, 0, 24);
1756 memcpy(resp->da, mgmt->sa, ETH_ALEN);
1757 memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1758 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1759 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1760 IEEE80211_STYPE_ACTION);
1761 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1762 resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1763 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1764 memcpy(resp->u.action.u.sa_query.trans_id,
1765 mgmt->u.action.u.sa_query.trans_id,
1766 WLAN_SA_QUERY_TR_ID_LEN);
1767
1768 ieee80211_tx_skb(sdata, skb, 1);
1769 }
1770
1771 static ieee80211_rx_result debug_noinline
1772 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1773 {
1774 struct ieee80211_local *local = rx->local;
1775 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1776 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1777 struct ieee80211_bss *bss;
1778 int len = rx->skb->len;
1779
1780 if (!ieee80211_is_action(mgmt->frame_control))
1781 return RX_CONTINUE;
1782
1783 if (!rx->sta)
1784 return RX_DROP_MONITOR;
1785
1786 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1787 return RX_DROP_MONITOR;
1788
1789 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1790 return RX_DROP_MONITOR;
1791
1792 /* all categories we currently handle have action_code */
1793 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1794 return RX_DROP_MONITOR;
1795
1796 switch (mgmt->u.action.category) {
1797 case WLAN_CATEGORY_BACK:
1798 /*
1799 * The aggregation code is not prepared to handle
1800 * anything but STA/AP due to the BSSID handling;
1801 * IBSS could work in the code but isn't supported
1802 * by drivers or the standard.
1803 */
1804 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1805 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1806 sdata->vif.type != NL80211_IFTYPE_AP)
1807 return RX_DROP_MONITOR;
1808
1809 switch (mgmt->u.action.u.addba_req.action_code) {
1810 case WLAN_ACTION_ADDBA_REQ:
1811 if (len < (IEEE80211_MIN_ACTION_SIZE +
1812 sizeof(mgmt->u.action.u.addba_req)))
1813 return RX_DROP_MONITOR;
1814 ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1815 break;
1816 case WLAN_ACTION_ADDBA_RESP:
1817 if (len < (IEEE80211_MIN_ACTION_SIZE +
1818 sizeof(mgmt->u.action.u.addba_resp)))
1819 return RX_DROP_MONITOR;
1820 ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1821 break;
1822 case WLAN_ACTION_DELBA:
1823 if (len < (IEEE80211_MIN_ACTION_SIZE +
1824 sizeof(mgmt->u.action.u.delba)))
1825 return RX_DROP_MONITOR;
1826 ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1827 break;
1828 }
1829 break;
1830 case WLAN_CATEGORY_SPECTRUM_MGMT:
1831 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1832 return RX_DROP_MONITOR;
1833
1834 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1835 return RX_DROP_MONITOR;
1836
1837 switch (mgmt->u.action.u.measurement.action_code) {
1838 case WLAN_ACTION_SPCT_MSR_REQ:
1839 if (len < (IEEE80211_MIN_ACTION_SIZE +
1840 sizeof(mgmt->u.action.u.measurement)))
1841 return RX_DROP_MONITOR;
1842 ieee80211_process_measurement_req(sdata, mgmt, len);
1843 break;
1844 case WLAN_ACTION_SPCT_CHL_SWITCH:
1845 if (len < (IEEE80211_MIN_ACTION_SIZE +
1846 sizeof(mgmt->u.action.u.chan_switch)))
1847 return RX_DROP_MONITOR;
1848
1849 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1850 return RX_DROP_MONITOR;
1851
1852 bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1853 local->hw.conf.channel->center_freq,
1854 sdata->u.mgd.ssid,
1855 sdata->u.mgd.ssid_len);
1856 if (!bss)
1857 return RX_DROP_MONITOR;
1858
1859 ieee80211_process_chanswitch(sdata,
1860 &mgmt->u.action.u.chan_switch.sw_elem, bss);
1861 ieee80211_rx_bss_put(local, bss);
1862 break;
1863 }
1864 break;
1865 case WLAN_CATEGORY_SA_QUERY:
1866 if (len < (IEEE80211_MIN_ACTION_SIZE +
1867 sizeof(mgmt->u.action.u.sa_query)))
1868 return RX_DROP_MONITOR;
1869 switch (mgmt->u.action.u.sa_query.action) {
1870 case WLAN_ACTION_SA_QUERY_REQUEST:
1871 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1872 return RX_DROP_MONITOR;
1873 ieee80211_process_sa_query_req(sdata, mgmt, len);
1874 break;
1875 case WLAN_ACTION_SA_QUERY_RESPONSE:
1876 /*
1877 * SA Query response is currently only used in AP mode
1878 * and it is processed in user space.
1879 */
1880 return RX_CONTINUE;
1881 }
1882 break;
1883 default:
1884 return RX_CONTINUE;
1885 }
1886
1887 rx->sta->rx_packets++;
1888 dev_kfree_skb(rx->skb);
1889 return RX_QUEUED;
1890 }
1891
1892 static ieee80211_rx_result debug_noinline
1893 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1894 {
1895 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1896 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1897
1898 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1899 return RX_DROP_MONITOR;
1900
1901 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1902 return RX_DROP_MONITOR;
1903
1904 if (ieee80211_vif_is_mesh(&sdata->vif))
1905 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1906
1907 if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1908 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1909
1910 if (sdata->vif.type == NL80211_IFTYPE_STATION)
1911 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1912
1913 return RX_DROP_MONITOR;
1914 }
1915
1916 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1917 struct ieee80211_hdr *hdr,
1918 struct ieee80211_rx_data *rx)
1919 {
1920 int keyidx;
1921 unsigned int hdrlen;
1922
1923 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1924 if (rx->skb->len >= hdrlen + 4)
1925 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1926 else
1927 keyidx = -1;
1928
1929 if (!rx->sta) {
1930 /*
1931 * Some hardware seem to generate incorrect Michael MIC
1932 * reports; ignore them to avoid triggering countermeasures.
1933 */
1934 goto ignore;
1935 }
1936
1937 if (!ieee80211_has_protected(hdr->frame_control))
1938 goto ignore;
1939
1940 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1941 /*
1942 * APs with pairwise keys should never receive Michael MIC
1943 * errors for non-zero keyidx because these are reserved for
1944 * group keys and only the AP is sending real multicast
1945 * frames in the BSS.
1946 */
1947 goto ignore;
1948 }
1949
1950 if (!ieee80211_is_data(hdr->frame_control) &&
1951 !ieee80211_is_auth(hdr->frame_control))
1952 goto ignore;
1953
1954 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL);
1955 ignore:
1956 dev_kfree_skb(rx->skb);
1957 rx->skb = NULL;
1958 }
1959
1960 /* TODO: use IEEE80211_RX_FRAGMENTED */
1961 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1962 {
1963 struct ieee80211_sub_if_data *sdata;
1964 struct ieee80211_local *local = rx->local;
1965 struct ieee80211_rtap_hdr {
1966 struct ieee80211_radiotap_header hdr;
1967 u8 flags;
1968 u8 rate;
1969 __le16 chan_freq;
1970 __le16 chan_flags;
1971 } __attribute__ ((packed)) *rthdr;
1972 struct sk_buff *skb = rx->skb, *skb2;
1973 struct net_device *prev_dev = NULL;
1974 struct ieee80211_rx_status *status = rx->status;
1975
1976 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1977 goto out_free_skb;
1978
1979 if (skb_headroom(skb) < sizeof(*rthdr) &&
1980 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1981 goto out_free_skb;
1982
1983 rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1984 memset(rthdr, 0, sizeof(*rthdr));
1985 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1986 rthdr->hdr.it_present =
1987 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1988 (1 << IEEE80211_RADIOTAP_RATE) |
1989 (1 << IEEE80211_RADIOTAP_CHANNEL));
1990
1991 rthdr->rate = rx->rate->bitrate / 5;
1992 rthdr->chan_freq = cpu_to_le16(status->freq);
1993
1994 if (status->band == IEEE80211_BAND_5GHZ)
1995 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1996 IEEE80211_CHAN_5GHZ);
1997 else
1998 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1999 IEEE80211_CHAN_2GHZ);
2000
2001 skb_set_mac_header(skb, 0);
2002 skb->ip_summed = CHECKSUM_UNNECESSARY;
2003 skb->pkt_type = PACKET_OTHERHOST;
2004 skb->protocol = htons(ETH_P_802_2);
2005
2006 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2007 if (!netif_running(sdata->dev))
2008 continue;
2009
2010 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2011 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2012 continue;
2013
2014 if (prev_dev) {
2015 skb2 = skb_clone(skb, GFP_ATOMIC);
2016 if (skb2) {
2017 skb2->dev = prev_dev;
2018 netif_rx(skb2);
2019 }
2020 }
2021
2022 prev_dev = sdata->dev;
2023 sdata->dev->stats.rx_packets++;
2024 sdata->dev->stats.rx_bytes += skb->len;
2025 }
2026
2027 if (prev_dev) {
2028 skb->dev = prev_dev;
2029 netif_rx(skb);
2030 skb = NULL;
2031 } else
2032 goto out_free_skb;
2033
2034 rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2035 return;
2036
2037 out_free_skb:
2038 dev_kfree_skb(skb);
2039 }
2040
2041
2042 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2043 struct ieee80211_rx_data *rx,
2044 struct sk_buff *skb)
2045 {
2046 ieee80211_rx_result res = RX_DROP_MONITOR;
2047
2048 rx->skb = skb;
2049 rx->sdata = sdata;
2050 rx->dev = sdata->dev;
2051
2052 #define CALL_RXH(rxh) \
2053 do { \
2054 res = rxh(rx); \
2055 if (res != RX_CONTINUE) \
2056 goto rxh_done; \
2057 } while (0);
2058
2059 CALL_RXH(ieee80211_rx_h_passive_scan)
2060 CALL_RXH(ieee80211_rx_h_check)
2061 CALL_RXH(ieee80211_rx_h_decrypt)
2062 CALL_RXH(ieee80211_rx_h_check_more_data)
2063 CALL_RXH(ieee80211_rx_h_sta_process)
2064 CALL_RXH(ieee80211_rx_h_defragment)
2065 CALL_RXH(ieee80211_rx_h_ps_poll)
2066 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2067 /* must be after MMIC verify so header is counted in MPDU mic */
2068 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2069 CALL_RXH(ieee80211_rx_h_amsdu)
2070 #ifdef CONFIG_MAC80211_MESH
2071 if (ieee80211_vif_is_mesh(&sdata->vif))
2072 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2073 #endif
2074 CALL_RXH(ieee80211_rx_h_data)
2075 CALL_RXH(ieee80211_rx_h_ctrl)
2076 CALL_RXH(ieee80211_rx_h_action)
2077 CALL_RXH(ieee80211_rx_h_mgmt)
2078
2079 #undef CALL_RXH
2080
2081 rxh_done:
2082 switch (res) {
2083 case RX_DROP_MONITOR:
2084 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2085 if (rx->sta)
2086 rx->sta->rx_dropped++;
2087 /* fall through */
2088 case RX_CONTINUE:
2089 ieee80211_rx_cooked_monitor(rx);
2090 break;
2091 case RX_DROP_UNUSABLE:
2092 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2093 if (rx->sta)
2094 rx->sta->rx_dropped++;
2095 dev_kfree_skb(rx->skb);
2096 break;
2097 case RX_QUEUED:
2098 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2099 break;
2100 }
2101 }
2102
2103 /* main receive path */
2104
2105 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2106 struct ieee80211_rx_data *rx,
2107 struct ieee80211_hdr *hdr)
2108 {
2109 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2110 int multicast = is_multicast_ether_addr(hdr->addr1);
2111
2112 switch (sdata->vif.type) {
2113 case NL80211_IFTYPE_STATION:
2114 if (!bssid)
2115 return 0;
2116 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2117 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2118 return 0;
2119 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2120 } else if (!multicast &&
2121 compare_ether_addr(sdata->dev->dev_addr,
2122 hdr->addr1) != 0) {
2123 if (!(sdata->dev->flags & IFF_PROMISC))
2124 return 0;
2125 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2126 }
2127 break;
2128 case NL80211_IFTYPE_ADHOC:
2129 if (!bssid)
2130 return 0;
2131 if (ieee80211_is_beacon(hdr->frame_control)) {
2132 return 1;
2133 }
2134 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2135 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2136 return 0;
2137 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2138 } else if (!multicast &&
2139 compare_ether_addr(sdata->dev->dev_addr,
2140 hdr->addr1) != 0) {
2141 if (!(sdata->dev->flags & IFF_PROMISC))
2142 return 0;
2143 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2144 } else if (!rx->sta) {
2145 int rate_idx;
2146 if (rx->status->flag & RX_FLAG_HT)
2147 rate_idx = 0; /* TODO: HT rates */
2148 else
2149 rate_idx = rx->status->rate_idx;
2150 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2151 BIT(rate_idx));
2152 }
2153 break;
2154 case NL80211_IFTYPE_MESH_POINT:
2155 if (!multicast &&
2156 compare_ether_addr(sdata->dev->dev_addr,
2157 hdr->addr1) != 0) {
2158 if (!(sdata->dev->flags & IFF_PROMISC))
2159 return 0;
2160
2161 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2162 }
2163 break;
2164 case NL80211_IFTYPE_AP_VLAN:
2165 case NL80211_IFTYPE_AP:
2166 if (!bssid) {
2167 if (compare_ether_addr(sdata->dev->dev_addr,
2168 hdr->addr1))
2169 return 0;
2170 } else if (!ieee80211_bssid_match(bssid,
2171 sdata->dev->dev_addr)) {
2172 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2173 return 0;
2174 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2175 }
2176 break;
2177 case NL80211_IFTYPE_WDS:
2178 if (bssid || !ieee80211_is_data(hdr->frame_control))
2179 return 0;
2180 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2181 return 0;
2182 break;
2183 case NL80211_IFTYPE_MONITOR:
2184 /* take everything */
2185 break;
2186 case NL80211_IFTYPE_UNSPECIFIED:
2187 case __NL80211_IFTYPE_AFTER_LAST:
2188 /* should never get here */
2189 WARN_ON(1);
2190 break;
2191 }
2192
2193 return 1;
2194 }
2195
2196 /*
2197 * This is the actual Rx frames handler. as it blongs to Rx path it must
2198 * be called with rcu_read_lock protection.
2199 */
2200 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2201 struct sk_buff *skb,
2202 struct ieee80211_rx_status *status,
2203 struct ieee80211_rate *rate)
2204 {
2205 struct ieee80211_local *local = hw_to_local(hw);
2206 struct ieee80211_sub_if_data *sdata;
2207 struct ieee80211_hdr *hdr;
2208 struct ieee80211_rx_data rx;
2209 int prepares;
2210 struct ieee80211_sub_if_data *prev = NULL;
2211 struct sk_buff *skb_new;
2212
2213 hdr = (struct ieee80211_hdr *)skb->data;
2214 memset(&rx, 0, sizeof(rx));
2215 rx.skb = skb;
2216 rx.local = local;
2217
2218 rx.status = status;
2219 rx.rate = rate;
2220
2221 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2222 local->dot11ReceivedFragmentCount++;
2223
2224 rx.sta = sta_info_get(local, hdr->addr2);
2225 if (rx.sta) {
2226 rx.sdata = rx.sta->sdata;
2227 rx.dev = rx.sta->sdata->dev;
2228 }
2229
2230 if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2231 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2232 return;
2233 }
2234
2235 if (unlikely(local->sw_scanning || local->hw_scanning))
2236 rx.flags |= IEEE80211_RX_IN_SCAN;
2237
2238 ieee80211_parse_qos(&rx);
2239 ieee80211_verify_alignment(&rx);
2240
2241 skb = rx.skb;
2242
2243 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2244 if (!netif_running(sdata->dev))
2245 continue;
2246
2247 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2248 continue;
2249
2250 rx.flags |= IEEE80211_RX_RA_MATCH;
2251 prepares = prepare_for_handlers(sdata, &rx, hdr);
2252
2253 if (!prepares)
2254 continue;
2255
2256 /*
2257 * frame is destined for this interface, but if it's not
2258 * also for the previous one we handle that after the
2259 * loop to avoid copying the SKB once too much
2260 */
2261
2262 if (!prev) {
2263 prev = sdata;
2264 continue;
2265 }
2266
2267 /*
2268 * frame was destined for the previous interface
2269 * so invoke RX handlers for it
2270 */
2271
2272 skb_new = skb_copy(skb, GFP_ATOMIC);
2273 if (!skb_new) {
2274 if (net_ratelimit())
2275 printk(KERN_DEBUG "%s: failed to copy "
2276 "multicast frame for %s\n",
2277 wiphy_name(local->hw.wiphy),
2278 prev->dev->name);
2279 continue;
2280 }
2281 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2282 prev = sdata;
2283 }
2284 if (prev)
2285 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2286 else
2287 dev_kfree_skb(skb);
2288 }
2289
2290 #define SEQ_MODULO 0x1000
2291 #define SEQ_MASK 0xfff
2292
2293 static inline int seq_less(u16 sq1, u16 sq2)
2294 {
2295 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2296 }
2297
2298 static inline u16 seq_inc(u16 sq)
2299 {
2300 return (sq + 1) & SEQ_MASK;
2301 }
2302
2303 static inline u16 seq_sub(u16 sq1, u16 sq2)
2304 {
2305 return (sq1 - sq2) & SEQ_MASK;
2306 }
2307
2308
2309 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
2310 struct tid_ampdu_rx *tid_agg_rx,
2311 int index)
2312 {
2313 struct ieee80211_supported_band *sband;
2314 struct ieee80211_rate *rate;
2315 struct ieee80211_rx_status status;
2316
2317 if (!tid_agg_rx->reorder_buf[index])
2318 goto no_frame;
2319
2320 /* release the reordered frames to stack */
2321 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb, sizeof(status));
2322 sband = hw->wiphy->bands[status.band];
2323 if (status.flag & RX_FLAG_HT)
2324 rate = sband->bitrates; /* TODO: HT rates */
2325 else
2326 rate = &sband->bitrates[status.rate_idx];
2327 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2328 &status, rate);
2329 tid_agg_rx->stored_mpdu_num--;
2330 tid_agg_rx->reorder_buf[index] = NULL;
2331
2332 no_frame:
2333 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2334 }
2335
2336
2337 /*
2338 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
2339 * the skb was added to the buffer longer than this time ago, the earlier
2340 * frames that have not yet been received are assumed to be lost and the skb
2341 * can be released for processing. This may also release other skb's from the
2342 * reorder buffer if there are no additional gaps between the frames.
2343 */
2344 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
2345
2346 /*
2347 * As it function blongs to Rx path it must be called with
2348 * the proper rcu_read_lock protection for its flow.
2349 */
2350 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2351 struct tid_ampdu_rx *tid_agg_rx,
2352 struct sk_buff *skb,
2353 struct ieee80211_rx_status *rxstatus,
2354 u16 mpdu_seq_num,
2355 int bar_req)
2356 {
2357 u16 head_seq_num, buf_size;
2358 int index;
2359
2360 buf_size = tid_agg_rx->buf_size;
2361 head_seq_num = tid_agg_rx->head_seq_num;
2362
2363 /* frame with out of date sequence number */
2364 if (seq_less(mpdu_seq_num, head_seq_num)) {
2365 dev_kfree_skb(skb);
2366 return 1;
2367 }
2368
2369 /* if frame sequence number exceeds our buffering window size or
2370 * block Ack Request arrived - release stored frames */
2371 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2372 /* new head to the ordering buffer */
2373 if (bar_req)
2374 head_seq_num = mpdu_seq_num;
2375 else
2376 head_seq_num =
2377 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2378 /* release stored frames up to new head to stack */
2379 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2380 index = seq_sub(tid_agg_rx->head_seq_num,
2381 tid_agg_rx->ssn)
2382 % tid_agg_rx->buf_size;
2383 ieee80211_release_reorder_frame(hw, tid_agg_rx,
2384 index);
2385 }
2386 if (bar_req)
2387 return 1;
2388 }
2389
2390 /* now the new frame is always in the range of the reordering */
2391 /* buffer window */
2392 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2393 % tid_agg_rx->buf_size;
2394 /* check if we already stored this frame */
2395 if (tid_agg_rx->reorder_buf[index]) {
2396 dev_kfree_skb(skb);
2397 return 1;
2398 }
2399
2400 /* if arrived mpdu is in the right order and nothing else stored */
2401 /* release it immediately */
2402 if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2403 tid_agg_rx->stored_mpdu_num == 0) {
2404 tid_agg_rx->head_seq_num =
2405 seq_inc(tid_agg_rx->head_seq_num);
2406 return 0;
2407 }
2408
2409 /* put the frame in the reordering buffer */
2410 tid_agg_rx->reorder_buf[index] = skb;
2411 tid_agg_rx->reorder_time[index] = jiffies;
2412 memcpy(tid_agg_rx->reorder_buf[index]->cb, rxstatus,
2413 sizeof(*rxstatus));
2414 tid_agg_rx->stored_mpdu_num++;
2415 /* release the buffer until next missing frame */
2416 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2417 % tid_agg_rx->buf_size;
2418 if (!tid_agg_rx->reorder_buf[index] &&
2419 tid_agg_rx->stored_mpdu_num > 1) {
2420 /*
2421 * No buffers ready to be released, but check whether any
2422 * frames in the reorder buffer have timed out.
2423 */
2424 int j;
2425 int skipped = 1;
2426 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
2427 j = (j + 1) % tid_agg_rx->buf_size) {
2428 if (tid_agg_rx->reorder_buf[j] == NULL) {
2429 skipped++;
2430 continue;
2431 }
2432 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
2433 HZ / 10))
2434 break;
2435
2436 #ifdef CONFIG_MAC80211_HT_DEBUG
2437 if (net_ratelimit())
2438 printk(KERN_DEBUG "%s: release an RX reorder "
2439 "frame due to timeout on earlier "
2440 "frames\n",
2441 wiphy_name(hw->wiphy));
2442 #endif
2443 ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
2444
2445 /*
2446 * Increment the head seq# also for the skipped slots.
2447 */
2448 tid_agg_rx->head_seq_num =
2449 (tid_agg_rx->head_seq_num + skipped) &
2450 SEQ_MASK;
2451 skipped = 0;
2452 }
2453 } else while (tid_agg_rx->reorder_buf[index]) {
2454 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
2455 index = seq_sub(tid_agg_rx->head_seq_num,
2456 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2457 }
2458 return 1;
2459 }
2460
2461 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2462 struct sk_buff *skb,
2463 struct ieee80211_rx_status *status)
2464 {
2465 struct ieee80211_hw *hw = &local->hw;
2466 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2467 struct sta_info *sta;
2468 struct tid_ampdu_rx *tid_agg_rx;
2469 u16 sc;
2470 u16 mpdu_seq_num;
2471 u8 ret = 0;
2472 int tid;
2473
2474 sta = sta_info_get(local, hdr->addr2);
2475 if (!sta)
2476 return ret;
2477
2478 /* filter the QoS data rx stream according to
2479 * STA/TID and check if this STA/TID is on aggregation */
2480 if (!ieee80211_is_data_qos(hdr->frame_control))
2481 goto end_reorder;
2482
2483 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2484
2485 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2486 goto end_reorder;
2487
2488 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2489
2490 /* qos null data frames are excluded */
2491 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2492 goto end_reorder;
2493
2494 /* new un-ordered ampdu frame - process it */
2495
2496 /* reset session timer */
2497 if (tid_agg_rx->timeout)
2498 mod_timer(&tid_agg_rx->session_timer,
2499 TU_TO_EXP_TIME(tid_agg_rx->timeout));
2500
2501 /* if this mpdu is fragmented - terminate rx aggregation session */
2502 sc = le16_to_cpu(hdr->seq_ctrl);
2503 if (sc & IEEE80211_SCTL_FRAG) {
2504 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2505 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2506 ret = 1;
2507 goto end_reorder;
2508 }
2509
2510 /* according to mpdu sequence number deal with reordering buffer */
2511 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2512 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, status,
2513 mpdu_seq_num, 0);
2514 end_reorder:
2515 return ret;
2516 }
2517
2518 /*
2519 * This is the receive path handler. It is called by a low level driver when an
2520 * 802.11 MPDU is received from the hardware.
2521 */
2522 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2523 struct ieee80211_rx_status *status)
2524 {
2525 struct ieee80211_local *local = hw_to_local(hw);
2526 struct ieee80211_rate *rate = NULL;
2527 struct ieee80211_supported_band *sband;
2528
2529 if (status->band < 0 ||
2530 status->band >= IEEE80211_NUM_BANDS) {
2531 WARN_ON(1);
2532 return;
2533 }
2534
2535 sband = local->hw.wiphy->bands[status->band];
2536 if (!sband) {
2537 WARN_ON(1);
2538 return;
2539 }
2540
2541 if (status->flag & RX_FLAG_HT) {
2542 /* rate_idx is MCS index */
2543 if (WARN_ON(status->rate_idx < 0 ||
2544 status->rate_idx >= 76))
2545 return;
2546 /* HT rates are not in the table - use the highest legacy rate
2547 * for now since other parts of mac80211 may not yet be fully
2548 * MCS aware. */
2549 rate = &sband->bitrates[sband->n_bitrates - 1];
2550 } else {
2551 if (WARN_ON(status->rate_idx < 0 ||
2552 status->rate_idx >= sband->n_bitrates))
2553 return;
2554 rate = &sband->bitrates[status->rate_idx];
2555 }
2556
2557 /*
2558 * key references and virtual interfaces are protected using RCU
2559 * and this requires that we are in a read-side RCU section during
2560 * receive processing
2561 */
2562 rcu_read_lock();
2563
2564 /*
2565 * Frames with failed FCS/PLCP checksum are not returned,
2566 * all other frames are returned without radiotap header
2567 * if it was previously present.
2568 * Also, frames with less than 16 bytes are dropped.
2569 */
2570 skb = ieee80211_rx_monitor(local, skb, status, rate);
2571 if (!skb) {
2572 rcu_read_unlock();
2573 return;
2574 }
2575
2576 /*
2577 * In theory, the block ack reordering should happen after duplicate
2578 * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
2579 * the call to ieee80211_rx_reorder_ampdu() should really be moved to
2580 * happen as a new RX handler between ieee80211_rx_h_check and
2581 * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
2582 * the time being, the call can be here since RX reorder buf processing
2583 * will implicitly skip duplicates. We could, in theory at least,
2584 * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
2585 * frames from other than operational channel), but that should not
2586 * happen in normal networks.
2587 */
2588 if (!ieee80211_rx_reorder_ampdu(local, skb, status))
2589 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2590
2591 rcu_read_unlock();
2592 }
2593 EXPORT_SYMBOL(__ieee80211_rx);
2594
2595 /* This is a version of the rx handler that can be called from hard irq
2596 * context. Post the skb on the queue and schedule the tasklet */
2597 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2598 struct ieee80211_rx_status *status)
2599 {
2600 struct ieee80211_local *local = hw_to_local(hw);
2601
2602 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2603
2604 skb->dev = local->mdev;
2605 /* copy status into skb->cb for use by tasklet */
2606 memcpy(skb->cb, status, sizeof(*status));
2607 skb->pkt_type = IEEE80211_RX_MSG;
2608 skb_queue_tail(&local->skb_queue, skb);
2609 tasklet_schedule(&local->tasklet);
2610 }
2611 EXPORT_SYMBOL(ieee80211_rx_irqsafe);