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mac80211: also drop qos-nullfunc frames silently
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / mac80211 / rx.c
blob51cb8bc3af81e68e41d9d5c4101b5c980cca77a4
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 u16 mpdu_seq_num,
34 int bar_req);
35 /*
36 * monitor mode reception
37 *
38 * This function cleans up the SKB, i.e. it removes all the stuff
39 * only useful for monitoring.
40 */
41 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
42 struct sk_buff *skb)
43 {
44 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
45 if (likely(skb->len > FCS_LEN))
46 skb_trim(skb, skb->len - FCS_LEN);
47 else {
48 /* driver bug */
49 WARN_ON(1);
50 dev_kfree_skb(skb);
51 skb = NULL;
52 }
53 }
54
55 return skb;
56 }
57
58 static inline int should_drop_frame(struct sk_buff *skb,
59 int present_fcs_len)
60 {
61 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
62 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
63
64 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
65 return 1;
66 if (unlikely(skb->len < 16 + present_fcs_len))
67 return 1;
68 if (ieee80211_is_ctl(hdr->frame_control) &&
69 !ieee80211_is_pspoll(hdr->frame_control) &&
70 !ieee80211_is_back_req(hdr->frame_control))
71 return 1;
72 return 0;
73 }
74
75 static int
76 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
77 struct ieee80211_rx_status *status)
78 {
79 int len;
80
81 /* always present fields */
82 len = sizeof(struct ieee80211_radiotap_header) + 9;
83
84 if (status->flag & RX_FLAG_TSFT)
85 len += 8;
86 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
87 len += 1;
88 if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
89 len += 1;
90
91 if (len & 1) /* padding for RX_FLAGS if necessary */
92 len++;
93
94 return len;
95 }
96
97 /*
98 * ieee80211_add_rx_radiotap_header - add radiotap header
99 *
100 * add a radiotap header containing all the fields which the hardware provided.
101 */
102 static void
103 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
104 struct sk_buff *skb,
105 struct ieee80211_rate *rate,
106 int rtap_len)
107 {
108 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
109 struct ieee80211_radiotap_header *rthdr;
110 unsigned char *pos;
111 u16 rx_flags = 0;
112
113 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
114 memset(rthdr, 0, rtap_len);
115
116 /* radiotap header, set always present flags */
117 rthdr->it_present =
118 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
119 (1 << IEEE80211_RADIOTAP_CHANNEL) |
120 (1 << IEEE80211_RADIOTAP_ANTENNA) |
121 (1 << IEEE80211_RADIOTAP_RX_FLAGS));
122 rthdr->it_len = cpu_to_le16(rtap_len);
123
124 pos = (unsigned char *)(rthdr+1);
125
126 /* the order of the following fields is important */
127
128 /* IEEE80211_RADIOTAP_TSFT */
129 if (status->flag & RX_FLAG_TSFT) {
130 put_unaligned_le64(status->mactime, pos);
131 rthdr->it_present |=
132 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
133 pos += 8;
134 }
135
136 /* IEEE80211_RADIOTAP_FLAGS */
137 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
138 *pos |= IEEE80211_RADIOTAP_F_FCS;
139 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
140 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
141 if (status->flag & RX_FLAG_SHORTPRE)
142 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
143 pos++;
144
145 /* IEEE80211_RADIOTAP_RATE */
146 if (status->flag & RX_FLAG_HT) {
147 /*
148 * TODO: add following information into radiotap header once
149 * suitable fields are defined for it:
150 * - MCS index (status->rate_idx)
151 * - HT40 (status->flag & RX_FLAG_40MHZ)
152 * - short-GI (status->flag & RX_FLAG_SHORT_GI)
153 */
154 *pos = 0;
155 } else {
156 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
157 *pos = rate->bitrate / 5;
158 }
159 pos++;
160
161 /* IEEE80211_RADIOTAP_CHANNEL */
162 put_unaligned_le16(status->freq, pos);
163 pos += 2;
164 if (status->band == IEEE80211_BAND_5GHZ)
165 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
166 pos);
167 else if (rate->flags & IEEE80211_RATE_ERP_G)
168 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
169 pos);
170 else
171 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
172 pos);
173 pos += 2;
174
175 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
176 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
177 *pos = status->signal;
178 rthdr->it_present |=
179 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
180 pos++;
181 }
182
183 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
184 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
185 *pos = status->noise;
186 rthdr->it_present |=
187 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
188 pos++;
189 }
190
191 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
192
193 /* IEEE80211_RADIOTAP_ANTENNA */
194 *pos = status->antenna;
195 pos++;
196
197 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
198
199 /* IEEE80211_RADIOTAP_RX_FLAGS */
200 /* ensure 2 byte alignment for the 2 byte field as required */
201 if ((pos - (u8 *)rthdr) & 1)
202 pos++;
203 if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
204 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
205 put_unaligned_le16(rx_flags, pos);
206 pos += 2;
207 }
208
209 /*
210 * This function copies a received frame to all monitor interfaces and
211 * returns a cleaned-up SKB that no longer includes the FCS nor the
212 * radiotap header the driver might have added.
213 */
214 static struct sk_buff *
215 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
216 struct ieee80211_rate *rate)
217 {
218 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
219 struct ieee80211_sub_if_data *sdata;
220 int needed_headroom = 0;
221 struct sk_buff *skb, *skb2;
222 struct net_device *prev_dev = NULL;
223 int present_fcs_len = 0;
224
225 /*
226 * First, we may need to make a copy of the skb because
227 * (1) we need to modify it for radiotap (if not present), and
228 * (2) the other RX handlers will modify the skb we got.
229 *
230 * We don't need to, of course, if we aren't going to return
231 * the SKB because it has a bad FCS/PLCP checksum.
232 */
233
234 /* room for the radiotap header based on driver features */
235 needed_headroom = ieee80211_rx_radiotap_len(local, status);
236
237 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
238 present_fcs_len = FCS_LEN;
239
240 if (!local->monitors) {
241 if (should_drop_frame(origskb, present_fcs_len)) {
242 dev_kfree_skb(origskb);
243 return NULL;
244 }
245
246 return remove_monitor_info(local, origskb);
247 }
248
249 if (should_drop_frame(origskb, present_fcs_len)) {
250 /* only need to expand headroom if necessary */
251 skb = origskb;
252 origskb = NULL;
253
254 /*
255 * This shouldn't trigger often because most devices have an
256 * RX header they pull before we get here, and that should
257 * be big enough for our radiotap information. We should
258 * probably export the length to drivers so that we can have
259 * them allocate enough headroom to start with.
260 */
261 if (skb_headroom(skb) < needed_headroom &&
262 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
263 dev_kfree_skb(skb);
264 return NULL;
265 }
266 } else {
267 /*
268 * Need to make a copy and possibly remove radiotap header
269 * and FCS from the original.
270 */
271 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
272
273 origskb = remove_monitor_info(local, origskb);
274
275 if (!skb)
276 return origskb;
277 }
278
279 /* prepend radiotap information */
280 ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
281
282 skb_reset_mac_header(skb);
283 skb->ip_summed = CHECKSUM_UNNECESSARY;
284 skb->pkt_type = PACKET_OTHERHOST;
285 skb->protocol = htons(ETH_P_802_2);
286
287 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
288 if (!netif_running(sdata->dev))
289 continue;
290
291 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
292 continue;
293
294 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
295 continue;
296
297 if (prev_dev) {
298 skb2 = skb_clone(skb, GFP_ATOMIC);
299 if (skb2) {
300 skb2->dev = prev_dev;
301 netif_rx(skb2);
302 }
303 }
304
305 prev_dev = sdata->dev;
306 sdata->dev->stats.rx_packets++;
307 sdata->dev->stats.rx_bytes += skb->len;
308 }
309
310 if (prev_dev) {
311 skb->dev = prev_dev;
312 netif_rx(skb);
313 } else
314 dev_kfree_skb(skb);
315
316 return origskb;
317 }
318
319
320 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
321 {
322 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
323 int tid;
324
325 /* does the frame have a qos control field? */
326 if (ieee80211_is_data_qos(hdr->frame_control)) {
327 u8 *qc = ieee80211_get_qos_ctl(hdr);
328 /* frame has qos control */
329 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
330 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
331 rx->flags |= IEEE80211_RX_AMSDU;
332 else
333 rx->flags &= ~IEEE80211_RX_AMSDU;
334 } else {
335 /*
336 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
337 *
338 * Sequence numbers for management frames, QoS data
339 * frames with a broadcast/multicast address in the
340 * Address 1 field, and all non-QoS data frames sent
341 * by QoS STAs are assigned using an additional single
342 * modulo-4096 counter, [...]
343 *
344 * We also use that counter for non-QoS STAs.
345 */
346 tid = NUM_RX_DATA_QUEUES - 1;
347 }
348
349 rx->queue = tid;
350 /* Set skb->priority to 1d tag if highest order bit of TID is not set.
351 * For now, set skb->priority to 0 for other cases. */
352 rx->skb->priority = (tid > 7) ? 0 : tid;
353 }
354
355 /**
356 * DOC: Packet alignment
357 *
358 * Drivers always need to pass packets that are aligned to two-byte boundaries
359 * to the stack.
360 *
361 * Additionally, should, if possible, align the payload data in a way that
362 * guarantees that the contained IP header is aligned to a four-byte
363 * boundary. In the case of regular frames, this simply means aligning the
364 * payload to a four-byte boundary (because either the IP header is directly
365 * contained, or IV/RFC1042 headers that have a length divisible by four are
366 * in front of it).
367 *
368 * With A-MSDU frames, however, the payload data address must yield two modulo
369 * four because there are 14-byte 802.3 headers within the A-MSDU frames that
370 * push the IP header further back to a multiple of four again. Thankfully, the
371 * specs were sane enough this time around to require padding each A-MSDU
372 * subframe to a length that is a multiple of four.
373 *
374 * Padding like Atheros hardware adds which is inbetween the 802.11 header and
375 * the payload is not supported, the driver is required to move the 802.11
376 * header to be directly in front of the payload in that case.
377 */
378 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
379 {
380 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
381 int hdrlen;
382
383 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
384 return;
385 #endif
386
387 if (WARN_ONCE((unsigned long)rx->skb->data & 1,
388 "unaligned packet at 0x%p\n", rx->skb->data))
389 return;
390
391 if (!ieee80211_is_data_present(hdr->frame_control))
392 return;
393
394 hdrlen = ieee80211_hdrlen(hdr->frame_control);
395 if (rx->flags & IEEE80211_RX_AMSDU)
396 hdrlen += ETH_HLEN;
397 WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
398 "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
399 }
400
401
402 /* rx handlers */
403
404 static ieee80211_rx_result debug_noinline
405 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
406 {
407 struct ieee80211_local *local = rx->local;
408 struct sk_buff *skb = rx->skb;
409
410 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
411 return ieee80211_scan_rx(rx->sdata, skb);
412
413 if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
414 (rx->flags & IEEE80211_RX_IN_SCAN))) {
415 /* drop all the other packets during a software scan anyway */
416 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
417 dev_kfree_skb(skb);
418 return RX_QUEUED;
419 }
420
421 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
422 /* scanning finished during invoking of handlers */
423 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
424 return RX_DROP_UNUSABLE;
425 }
426
427 return RX_CONTINUE;
428 }
429
430
431 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
432 {
433 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
434
435 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
436 return 0;
437
438 return ieee80211_is_robust_mgmt_frame(hdr);
439 }
440
441
442 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
443 {
444 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
445
446 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
447 return 0;
448
449 return ieee80211_is_robust_mgmt_frame(hdr);
450 }
451
452
453 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
454 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
455 {
456 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
457 struct ieee80211_mmie *mmie;
458
459 if (skb->len < 24 + sizeof(*mmie) ||
460 !is_multicast_ether_addr(hdr->da))
461 return -1;
462
463 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
464 return -1; /* not a robust management frame */
465
466 mmie = (struct ieee80211_mmie *)
467 (skb->data + skb->len - sizeof(*mmie));
468 if (mmie->element_id != WLAN_EID_MMIE ||
469 mmie->length != sizeof(*mmie) - 2)
470 return -1;
471
472 return le16_to_cpu(mmie->key_id);
473 }
474
475
476 static ieee80211_rx_result
477 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
478 {
479 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
480 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
481 char *dev_addr = rx->dev->dev_addr;
482
483 if (ieee80211_is_data(hdr->frame_control)) {
484 if (is_multicast_ether_addr(hdr->addr1)) {
485 if (ieee80211_has_tods(hdr->frame_control) ||
486 !ieee80211_has_fromds(hdr->frame_control))
487 return RX_DROP_MONITOR;
488 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
489 return RX_DROP_MONITOR;
490 } else {
491 if (!ieee80211_has_a4(hdr->frame_control))
492 return RX_DROP_MONITOR;
493 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
494 return RX_DROP_MONITOR;
495 }
496 }
497
498 /* If there is not an established peer link and this is not a peer link
499 * establisment frame, beacon or probe, drop the frame.
500 */
501
502 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
503 struct ieee80211_mgmt *mgmt;
504
505 if (!ieee80211_is_mgmt(hdr->frame_control))
506 return RX_DROP_MONITOR;
507
508 if (ieee80211_is_action(hdr->frame_control)) {
509 mgmt = (struct ieee80211_mgmt *)hdr;
510 if (mgmt->u.action.category != PLINK_CATEGORY)
511 return RX_DROP_MONITOR;
512 return RX_CONTINUE;
513 }
514
515 if (ieee80211_is_probe_req(hdr->frame_control) ||
516 ieee80211_is_probe_resp(hdr->frame_control) ||
517 ieee80211_is_beacon(hdr->frame_control))
518 return RX_CONTINUE;
519
520 return RX_DROP_MONITOR;
521
522 }
523
524 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
525
526 if (ieee80211_is_data(hdr->frame_control) &&
527 is_multicast_ether_addr(hdr->addr1) &&
528 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
529 return RX_DROP_MONITOR;
530 #undef msh_h_get
531
532 return RX_CONTINUE;
533 }
534
535
536 static ieee80211_rx_result debug_noinline
537 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
538 {
539 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
540
541 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
542 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
543 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
544 rx->sta->last_seq_ctrl[rx->queue] ==
545 hdr->seq_ctrl)) {
546 if (rx->flags & IEEE80211_RX_RA_MATCH) {
547 rx->local->dot11FrameDuplicateCount++;
548 rx->sta->num_duplicates++;
549 }
550 return RX_DROP_MONITOR;
551 } else
552 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
553 }
554
555 if (unlikely(rx->skb->len < 16)) {
556 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
557 return RX_DROP_MONITOR;
558 }
559
560 /* Drop disallowed frame classes based on STA auth/assoc state;
561 * IEEE 802.11, Chap 5.5.
562 *
563 * mac80211 filters only based on association state, i.e. it drops
564 * Class 3 frames from not associated stations. hostapd sends
565 * deauth/disassoc frames when needed. In addition, hostapd is
566 * responsible for filtering on both auth and assoc states.
567 */
568
569 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
570 return ieee80211_rx_mesh_check(rx);
571
572 if (unlikely((ieee80211_is_data(hdr->frame_control) ||
573 ieee80211_is_pspoll(hdr->frame_control)) &&
574 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
575 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
576 if ((!ieee80211_has_fromds(hdr->frame_control) &&
577 !ieee80211_has_tods(hdr->frame_control) &&
578 ieee80211_is_data(hdr->frame_control)) ||
579 !(rx->flags & IEEE80211_RX_RA_MATCH)) {
580 /* Drop IBSS frames and frames for other hosts
581 * silently. */
582 return RX_DROP_MONITOR;
583 }
584
585 return RX_DROP_MONITOR;
586 }
587
588 return RX_CONTINUE;
589 }
590
591
592 static ieee80211_rx_result debug_noinline
593 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
594 {
595 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
596 int keyidx;
597 int hdrlen;
598 ieee80211_rx_result result = RX_DROP_UNUSABLE;
599 struct ieee80211_key *stakey = NULL;
600 int mmie_keyidx = -1;
601
602 /*
603 * Key selection 101
604 *
605 * There are four types of keys:
606 * - GTK (group keys)
607 * - IGTK (group keys for management frames)
608 * - PTK (pairwise keys)
609 * - STK (station-to-station pairwise keys)
610 *
611 * When selecting a key, we have to distinguish between multicast
612 * (including broadcast) and unicast frames, the latter can only
613 * use PTKs and STKs while the former always use GTKs and IGTKs.
614 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
615 * unicast frames can also use key indices like GTKs. Hence, if we
616 * don't have a PTK/STK we check the key index for a WEP key.
617 *
618 * Note that in a regular BSS, multicast frames are sent by the
619 * AP only, associated stations unicast the frame to the AP first
620 * which then multicasts it on their behalf.
621 *
622 * There is also a slight problem in IBSS mode: GTKs are negotiated
623 * with each station, that is something we don't currently handle.
624 * The spec seems to expect that one negotiates the same key with
625 * every station but there's no such requirement; VLANs could be
626 * possible.
627 */
628
629 /*
630 * No point in finding a key and decrypting if the frame is neither
631 * addressed to us nor a multicast frame.
632 */
633 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
634 return RX_CONTINUE;
635
636 if (rx->sta)
637 stakey = rcu_dereference(rx->sta->key);
638
639 if (!ieee80211_has_protected(hdr->frame_control))
640 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
641
642 if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
643 rx->key = stakey;
644 /* Skip decryption if the frame is not protected. */
645 if (!ieee80211_has_protected(hdr->frame_control))
646 return RX_CONTINUE;
647 } else if (mmie_keyidx >= 0) {
648 /* Broadcast/multicast robust management frame / BIP */
649 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
650 (rx->status->flag & RX_FLAG_IV_STRIPPED))
651 return RX_CONTINUE;
652
653 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
654 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
655 return RX_DROP_MONITOR; /* unexpected BIP keyidx */
656 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
657 } else if (!ieee80211_has_protected(hdr->frame_control)) {
658 /*
659 * The frame was not protected, so skip decryption. However, we
660 * need to set rx->key if there is a key that could have been
661 * used so that the frame may be dropped if encryption would
662 * have been expected.
663 */
664 struct ieee80211_key *key = NULL;
665 if (ieee80211_is_mgmt(hdr->frame_control) &&
666 is_multicast_ether_addr(hdr->addr1) &&
667 (key = rcu_dereference(rx->sdata->default_mgmt_key)))
668 rx->key = key;
669 else if ((key = rcu_dereference(rx->sdata->default_key)))
670 rx->key = key;
671 return RX_CONTINUE;
672 } else {
673 /*
674 * The device doesn't give us the IV so we won't be
675 * able to look up the key. That's ok though, we
676 * don't need to decrypt the frame, we just won't
677 * be able to keep statistics accurate.
678 * Except for key threshold notifications, should
679 * we somehow allow the driver to tell us which key
680 * the hardware used if this flag is set?
681 */
682 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
683 (rx->status->flag & RX_FLAG_IV_STRIPPED))
684 return RX_CONTINUE;
685
686 hdrlen = ieee80211_hdrlen(hdr->frame_control);
687
688 if (rx->skb->len < 8 + hdrlen)
689 return RX_DROP_UNUSABLE; /* TODO: count this? */
690
691 /*
692 * no need to call ieee80211_wep_get_keyidx,
693 * it verifies a bunch of things we've done already
694 */
695 keyidx = rx->skb->data[hdrlen + 3] >> 6;
696
697 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
698
699 /*
700 * RSNA-protected unicast frames should always be sent with
701 * pairwise or station-to-station keys, but for WEP we allow
702 * using a key index as well.
703 */
704 if (rx->key && rx->key->conf.alg != ALG_WEP &&
705 !is_multicast_ether_addr(hdr->addr1))
706 rx->key = NULL;
707 }
708
709 if (rx->key) {
710 rx->key->tx_rx_count++;
711 /* TODO: add threshold stuff again */
712 } else {
713 return RX_DROP_MONITOR;
714 }
715
716 /* Check for weak IVs if possible */
717 if (rx->sta && rx->key->conf.alg == ALG_WEP &&
718 ieee80211_is_data(hdr->frame_control) &&
719 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
720 !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
721 ieee80211_wep_is_weak_iv(rx->skb, rx->key))
722 rx->sta->wep_weak_iv_count++;
723
724 switch (rx->key->conf.alg) {
725 case ALG_WEP:
726 result = ieee80211_crypto_wep_decrypt(rx);
727 break;
728 case ALG_TKIP:
729 result = ieee80211_crypto_tkip_decrypt(rx);
730 break;
731 case ALG_CCMP:
732 result = ieee80211_crypto_ccmp_decrypt(rx);
733 break;
734 case ALG_AES_CMAC:
735 result = ieee80211_crypto_aes_cmac_decrypt(rx);
736 break;
737 }
738
739 /* either the frame has been decrypted or will be dropped */
740 rx->status->flag |= RX_FLAG_DECRYPTED;
741
742 return result;
743 }
744
745 static ieee80211_rx_result debug_noinline
746 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
747 {
748 struct ieee80211_local *local;
749 struct ieee80211_hdr *hdr;
750 struct sk_buff *skb;
751
752 local = rx->local;
753 skb = rx->skb;
754 hdr = (struct ieee80211_hdr *) skb->data;
755
756 if (!local->pspolling)
757 return RX_CONTINUE;
758
759 if (!ieee80211_has_fromds(hdr->frame_control))
760 /* this is not from AP */
761 return RX_CONTINUE;
762
763 if (!ieee80211_is_data(hdr->frame_control))
764 return RX_CONTINUE;
765
766 if (!ieee80211_has_moredata(hdr->frame_control)) {
767 /* AP has no more frames buffered for us */
768 local->pspolling = false;
769 return RX_CONTINUE;
770 }
771
772 /* more data bit is set, let's request a new frame from the AP */
773 ieee80211_send_pspoll(local, rx->sdata);
774
775 return RX_CONTINUE;
776 }
777
778 static void ap_sta_ps_start(struct sta_info *sta)
779 {
780 struct ieee80211_sub_if_data *sdata = sta->sdata;
781 struct ieee80211_local *local = sdata->local;
782
783 atomic_inc(&sdata->bss->num_sta_ps);
784 set_sta_flags(sta, WLAN_STA_PS);
785 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
786 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
787 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
788 sdata->dev->name, sta->sta.addr, sta->sta.aid);
789 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
790 }
791
792 static int ap_sta_ps_end(struct sta_info *sta)
793 {
794 struct ieee80211_sub_if_data *sdata = sta->sdata;
795 struct ieee80211_local *local = sdata->local;
796 int sent, buffered;
797
798 atomic_dec(&sdata->bss->num_sta_ps);
799
800 clear_sta_flags(sta, WLAN_STA_PS);
801 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
802
803 if (!skb_queue_empty(&sta->ps_tx_buf))
804 sta_info_clear_tim_bit(sta);
805
806 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
807 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
808 sdata->dev->name, sta->sta.addr, sta->sta.aid);
809 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
810
811 /* Send all buffered frames to the station */
812 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
813 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf);
814 sent += buffered;
815 local->total_ps_buffered -= buffered;
816
817 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
818 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
819 "since STA not sleeping anymore\n", sdata->dev->name,
820 sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
821 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
822
823 return sent;
824 }
825
826 static ieee80211_rx_result debug_noinline
827 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
828 {
829 struct sta_info *sta = rx->sta;
830 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
831
832 if (!sta)
833 return RX_CONTINUE;
834
835 /*
836 * Update last_rx only for IBSS packets which are for the current
837 * BSSID to avoid keeping the current IBSS network alive in cases
838 * where other STAs start using different BSSID.
839 */
840 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
841 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
842 NL80211_IFTYPE_ADHOC);
843 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
844 sta->last_rx = jiffies;
845 } else if (!is_multicast_ether_addr(hdr->addr1)) {
846 /*
847 * Mesh beacons will update last_rx when if they are found to
848 * match the current local configuration when processed.
849 */
850 sta->last_rx = jiffies;
851 }
852
853 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
854 return RX_CONTINUE;
855
856 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
857 ieee80211_sta_rx_notify(rx->sdata, hdr);
858
859 sta->rx_fragments++;
860 sta->rx_bytes += rx->skb->len;
861 sta->last_signal = rx->status->signal;
862 sta->last_noise = rx->status->noise;
863
864 /*
865 * Change STA power saving mode only at the end of a frame
866 * exchange sequence.
867 */
868 if (!ieee80211_has_morefrags(hdr->frame_control) &&
869 (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
870 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
871 if (test_sta_flags(sta, WLAN_STA_PS)) {
872 /*
873 * Ignore doze->wake transitions that are
874 * indicated by non-data frames, the standard
875 * is unclear here, but for example going to
876 * PS mode and then scanning would cause a
877 * doze->wake transition for the probe request,
878 * and that is clearly undesirable.
879 */
880 if (ieee80211_is_data(hdr->frame_control) &&
881 !ieee80211_has_pm(hdr->frame_control))
882 rx->sent_ps_buffered += ap_sta_ps_end(sta);
883 } else {
884 if (ieee80211_has_pm(hdr->frame_control))
885 ap_sta_ps_start(sta);
886 }
887 }
888
889 /*
890 * Drop (qos-)data::nullfunc frames silently, since they
891 * are used only to control station power saving mode.
892 */
893 if (ieee80211_is_nullfunc(hdr->frame_control) ||
894 ieee80211_is_qos_nullfunc(hdr->frame_control)) {
895 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
896 /*
897 * Update counter and free packet here to avoid
898 * counting this as a dropped packed.
899 */
900 sta->rx_packets++;
901 dev_kfree_skb(rx->skb);
902 return RX_QUEUED;
903 }
904
905 return RX_CONTINUE;
906 } /* ieee80211_rx_h_sta_process */
907
908 static inline struct ieee80211_fragment_entry *
909 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
910 unsigned int frag, unsigned int seq, int rx_queue,
911 struct sk_buff **skb)
912 {
913 struct ieee80211_fragment_entry *entry;
914 int idx;
915
916 idx = sdata->fragment_next;
917 entry = &sdata->fragments[sdata->fragment_next++];
918 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
919 sdata->fragment_next = 0;
920
921 if (!skb_queue_empty(&entry->skb_list)) {
922 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
923 struct ieee80211_hdr *hdr =
924 (struct ieee80211_hdr *) entry->skb_list.next->data;
925 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
926 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
927 "addr1=%pM addr2=%pM\n",
928 sdata->dev->name, idx,
929 jiffies - entry->first_frag_time, entry->seq,
930 entry->last_frag, hdr->addr1, hdr->addr2);
931 #endif
932 __skb_queue_purge(&entry->skb_list);
933 }
934
935 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
936 *skb = NULL;
937 entry->first_frag_time = jiffies;
938 entry->seq = seq;
939 entry->rx_queue = rx_queue;
940 entry->last_frag = frag;
941 entry->ccmp = 0;
942 entry->extra_len = 0;
943
944 return entry;
945 }
946
947 static inline struct ieee80211_fragment_entry *
948 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
949 unsigned int frag, unsigned int seq,
950 int rx_queue, struct ieee80211_hdr *hdr)
951 {
952 struct ieee80211_fragment_entry *entry;
953 int i, idx;
954
955 idx = sdata->fragment_next;
956 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
957 struct ieee80211_hdr *f_hdr;
958
959 idx--;
960 if (idx < 0)
961 idx = IEEE80211_FRAGMENT_MAX - 1;
962
963 entry = &sdata->fragments[idx];
964 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
965 entry->rx_queue != rx_queue ||
966 entry->last_frag + 1 != frag)
967 continue;
968
969 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
970
971 /*
972 * Check ftype and addresses are equal, else check next fragment
973 */
974 if (((hdr->frame_control ^ f_hdr->frame_control) &
975 cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
976 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
977 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
978 continue;
979
980 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
981 __skb_queue_purge(&entry->skb_list);
982 continue;
983 }
984 return entry;
985 }
986
987 return NULL;
988 }
989
990 static ieee80211_rx_result debug_noinline
991 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
992 {
993 struct ieee80211_hdr *hdr;
994 u16 sc;
995 __le16 fc;
996 unsigned int frag, seq;
997 struct ieee80211_fragment_entry *entry;
998 struct sk_buff *skb;
999
1000 hdr = (struct ieee80211_hdr *)rx->skb->data;
1001 fc = hdr->frame_control;
1002 sc = le16_to_cpu(hdr->seq_ctrl);
1003 frag = sc & IEEE80211_SCTL_FRAG;
1004
1005 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1006 (rx->skb)->len < 24 ||
1007 is_multicast_ether_addr(hdr->addr1))) {
1008 /* not fragmented */
1009 goto out;
1010 }
1011 I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1012
1013 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1014
1015 if (frag == 0) {
1016 /* This is the first fragment of a new frame. */
1017 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1018 rx->queue, &(rx->skb));
1019 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1020 ieee80211_has_protected(fc)) {
1021 /* Store CCMP PN so that we can verify that the next
1022 * fragment has a sequential PN value. */
1023 entry->ccmp = 1;
1024 memcpy(entry->last_pn,
1025 rx->key->u.ccmp.rx_pn[rx->queue],
1026 CCMP_PN_LEN);
1027 }
1028 return RX_QUEUED;
1029 }
1030
1031 /* This is a fragment for a frame that should already be pending in
1032 * fragment cache. Add this fragment to the end of the pending entry.
1033 */
1034 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1035 if (!entry) {
1036 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1037 return RX_DROP_MONITOR;
1038 }
1039
1040 /* Verify that MPDUs within one MSDU have sequential PN values.
1041 * (IEEE 802.11i, 8.3.3.4.5) */
1042 if (entry->ccmp) {
1043 int i;
1044 u8 pn[CCMP_PN_LEN], *rpn;
1045 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1046 return RX_DROP_UNUSABLE;
1047 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1048 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1049 pn[i]++;
1050 if (pn[i])
1051 break;
1052 }
1053 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1054 if (memcmp(pn, rpn, CCMP_PN_LEN))
1055 return RX_DROP_UNUSABLE;
1056 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1057 }
1058
1059 skb_pull(rx->skb, ieee80211_hdrlen(fc));
1060 __skb_queue_tail(&entry->skb_list, rx->skb);
1061 entry->last_frag = frag;
1062 entry->extra_len += rx->skb->len;
1063 if (ieee80211_has_morefrags(fc)) {
1064 rx->skb = NULL;
1065 return RX_QUEUED;
1066 }
1067
1068 rx->skb = __skb_dequeue(&entry->skb_list);
1069 if (skb_tailroom(rx->skb) < entry->extra_len) {
1070 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1071 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1072 GFP_ATOMIC))) {
1073 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1074 __skb_queue_purge(&entry->skb_list);
1075 return RX_DROP_UNUSABLE;
1076 }
1077 }
1078 while ((skb = __skb_dequeue(&entry->skb_list))) {
1079 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1080 dev_kfree_skb(skb);
1081 }
1082
1083 /* Complete frame has been reassembled - process it now */
1084 rx->flags |= IEEE80211_RX_FRAGMENTED;
1085
1086 out:
1087 if (rx->sta)
1088 rx->sta->rx_packets++;
1089 if (is_multicast_ether_addr(hdr->addr1))
1090 rx->local->dot11MulticastReceivedFrameCount++;
1091 else
1092 ieee80211_led_rx(rx->local);
1093 return RX_CONTINUE;
1094 }
1095
1096 static ieee80211_rx_result debug_noinline
1097 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1098 {
1099 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1100 struct sk_buff *skb;
1101 int no_pending_pkts;
1102 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1103
1104 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1105 !(rx->flags & IEEE80211_RX_RA_MATCH)))
1106 return RX_CONTINUE;
1107
1108 if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1109 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1110 return RX_DROP_UNUSABLE;
1111
1112 skb = skb_dequeue(&rx->sta->tx_filtered);
1113 if (!skb) {
1114 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1115 if (skb)
1116 rx->local->total_ps_buffered--;
1117 }
1118 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1119 skb_queue_empty(&rx->sta->ps_tx_buf);
1120
1121 if (skb) {
1122 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1123 struct ieee80211_hdr *hdr =
1124 (struct ieee80211_hdr *) skb->data;
1125
1126 /*
1127 * Tell TX path to send this frame even though the STA may
1128 * still remain is PS mode after this frame exchange.
1129 */
1130 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
1131
1132 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1133 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1134 rx->sta->sta.addr, rx->sta->sta.aid,
1135 skb_queue_len(&rx->sta->ps_tx_buf));
1136 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1137
1138 /* Use MoreData flag to indicate whether there are more
1139 * buffered frames for this STA */
1140 if (no_pending_pkts)
1141 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1142 else
1143 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1144
1145 ieee80211_add_pending_skb(rx->local, skb);
1146
1147 if (no_pending_pkts)
1148 sta_info_clear_tim_bit(rx->sta);
1149 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1150 } else if (!rx->sent_ps_buffered) {
1151 /*
1152 * FIXME: This can be the result of a race condition between
1153 * us expiring a frame and the station polling for it.
1154 * Should we send it a null-func frame indicating we
1155 * have nothing buffered for it?
1156 */
1157 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1158 "though there are no buffered frames for it\n",
1159 rx->dev->name, rx->sta->sta.addr);
1160 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1161 }
1162
1163 /* Free PS Poll skb here instead of returning RX_DROP that would
1164 * count as an dropped frame. */
1165 dev_kfree_skb(rx->skb);
1166
1167 return RX_QUEUED;
1168 }
1169
1170 static ieee80211_rx_result debug_noinline
1171 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1172 {
1173 u8 *data = rx->skb->data;
1174 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1175
1176 if (!ieee80211_is_data_qos(hdr->frame_control))
1177 return RX_CONTINUE;
1178
1179 /* remove the qos control field, update frame type and meta-data */
1180 memmove(data + IEEE80211_QOS_CTL_LEN, data,
1181 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1182 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1183 /* change frame type to non QOS */
1184 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1185
1186 return RX_CONTINUE;
1187 }
1188
1189 static int
1190 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1191 {
1192 if (unlikely(!rx->sta ||
1193 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1194 return -EACCES;
1195
1196 return 0;
1197 }
1198
1199 static int
1200 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1201 {
1202 /*
1203 * Pass through unencrypted frames if the hardware has
1204 * decrypted them already.
1205 */
1206 if (rx->status->flag & RX_FLAG_DECRYPTED)
1207 return 0;
1208
1209 /* Drop unencrypted frames if key is set. */
1210 if (unlikely(!ieee80211_has_protected(fc) &&
1211 !ieee80211_is_nullfunc(fc) &&
1212 ieee80211_is_data(fc) &&
1213 (rx->key || rx->sdata->drop_unencrypted)))
1214 return -EACCES;
1215 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1216 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1217 rx->key))
1218 return -EACCES;
1219 /* BIP does not use Protected field, so need to check MMIE */
1220 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
1221 && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1222 rx->key))
1223 return -EACCES;
1224 /*
1225 * When using MFP, Action frames are not allowed prior to
1226 * having configured keys.
1227 */
1228 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1229 ieee80211_is_robust_mgmt_frame(
1230 (struct ieee80211_hdr *) rx->skb->data)))
1231 return -EACCES;
1232 }
1233
1234 return 0;
1235 }
1236
1237 static int
1238 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1239 {
1240 struct net_device *dev = rx->dev;
1241 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1242
1243 return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type);
1244 }
1245
1246 /*
1247 * requires that rx->skb is a frame with ethernet header
1248 */
1249 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1250 {
1251 static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1252 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1253 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1254
1255 /*
1256 * Allow EAPOL frames to us/the PAE group address regardless
1257 * of whether the frame was encrypted or not.
1258 */
1259 if (ehdr->h_proto == htons(ETH_P_PAE) &&
1260 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1261 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1262 return true;
1263
1264 if (ieee80211_802_1x_port_control(rx) ||
1265 ieee80211_drop_unencrypted(rx, fc))
1266 return false;
1267
1268 return true;
1269 }
1270
1271 /*
1272 * requires that rx->skb is a frame with ethernet header
1273 */
1274 static void
1275 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1276 {
1277 struct net_device *dev = rx->dev;
1278 struct ieee80211_local *local = rx->local;
1279 struct sk_buff *skb, *xmit_skb;
1280 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1281 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1282 struct sta_info *dsta;
1283
1284 skb = rx->skb;
1285 xmit_skb = NULL;
1286
1287 if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1288 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1289 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1290 (rx->flags & IEEE80211_RX_RA_MATCH)) {
1291 if (is_multicast_ether_addr(ehdr->h_dest)) {
1292 /*
1293 * send multicast frames both to higher layers in
1294 * local net stack and back to the wireless medium
1295 */
1296 xmit_skb = skb_copy(skb, GFP_ATOMIC);
1297 if (!xmit_skb && net_ratelimit())
1298 printk(KERN_DEBUG "%s: failed to clone "
1299 "multicast frame\n", dev->name);
1300 } else {
1301 dsta = sta_info_get(local, skb->data);
1302 if (dsta && dsta->sdata->dev == dev) {
1303 /*
1304 * The destination station is associated to
1305 * this AP (in this VLAN), so send the frame
1306 * directly to it and do not pass it to local
1307 * net stack.
1308 */
1309 xmit_skb = skb;
1310 skb = NULL;
1311 }
1312 }
1313 }
1314
1315 if (skb) {
1316 int align __maybe_unused;
1317
1318 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1319 /*
1320 * 'align' will only take the values 0 or 2 here
1321 * since all frames are required to be aligned
1322 * to 2-byte boundaries when being passed to
1323 * mac80211. That also explains the __skb_push()
1324 * below.
1325 */
1326 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1327 if (align) {
1328 if (WARN_ON(skb_headroom(skb) < 3)) {
1329 dev_kfree_skb(skb);
1330 skb = NULL;
1331 } else {
1332 u8 *data = skb->data;
1333 size_t len = skb_headlen(skb);
1334 skb->data -= align;
1335 memmove(skb->data, data, len);
1336 skb_set_tail_pointer(skb, len);
1337 }
1338 }
1339 #endif
1340
1341 if (skb) {
1342 /* deliver to local stack */
1343 skb->protocol = eth_type_trans(skb, dev);
1344 memset(skb->cb, 0, sizeof(skb->cb));
1345 netif_rx(skb);
1346 }
1347 }
1348
1349 if (xmit_skb) {
1350 /* send to wireless media */
1351 xmit_skb->protocol = htons(ETH_P_802_3);
1352 skb_reset_network_header(xmit_skb);
1353 skb_reset_mac_header(xmit_skb);
1354 dev_queue_xmit(xmit_skb);
1355 }
1356 }
1357
1358 static ieee80211_rx_result debug_noinline
1359 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1360 {
1361 struct net_device *dev = rx->dev;
1362 struct ieee80211_local *local = rx->local;
1363 u16 ethertype;
1364 u8 *payload;
1365 struct sk_buff *skb = rx->skb, *frame = NULL;
1366 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1367 __le16 fc = hdr->frame_control;
1368 const struct ethhdr *eth;
1369 int remaining, err;
1370 u8 dst[ETH_ALEN];
1371 u8 src[ETH_ALEN];
1372
1373 if (unlikely(!ieee80211_is_data(fc)))
1374 return RX_CONTINUE;
1375
1376 if (unlikely(!ieee80211_is_data_present(fc)))
1377 return RX_DROP_MONITOR;
1378
1379 if (!(rx->flags & IEEE80211_RX_AMSDU))
1380 return RX_CONTINUE;
1381
1382 err = __ieee80211_data_to_8023(rx);
1383 if (unlikely(err))
1384 return RX_DROP_UNUSABLE;
1385
1386 skb->dev = dev;
1387
1388 dev->stats.rx_packets++;
1389 dev->stats.rx_bytes += skb->len;
1390
1391 /* skip the wrapping header */
1392 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1393 if (!eth)
1394 return RX_DROP_UNUSABLE;
1395
1396 while (skb != frame) {
1397 u8 padding;
1398 __be16 len = eth->h_proto;
1399 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1400
1401 remaining = skb->len;
1402 memcpy(dst, eth->h_dest, ETH_ALEN);
1403 memcpy(src, eth->h_source, ETH_ALEN);
1404
1405 padding = ((4 - subframe_len) & 0x3);
1406 /* the last MSDU has no padding */
1407 if (subframe_len > remaining)
1408 return RX_DROP_UNUSABLE;
1409
1410 skb_pull(skb, sizeof(struct ethhdr));
1411 /* if last subframe reuse skb */
1412 if (remaining <= subframe_len + padding)
1413 frame = skb;
1414 else {
1415 /*
1416 * Allocate and reserve two bytes more for payload
1417 * alignment since sizeof(struct ethhdr) is 14.
1418 */
1419 frame = dev_alloc_skb(
1420 ALIGN(local->hw.extra_tx_headroom, 4) +
1421 subframe_len + 2);
1422
1423 if (frame == NULL)
1424 return RX_DROP_UNUSABLE;
1425
1426 skb_reserve(frame,
1427 ALIGN(local->hw.extra_tx_headroom, 4) +
1428 sizeof(struct ethhdr) + 2);
1429 memcpy(skb_put(frame, ntohs(len)), skb->data,
1430 ntohs(len));
1431
1432 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1433 padding);
1434 if (!eth) {
1435 dev_kfree_skb(frame);
1436 return RX_DROP_UNUSABLE;
1437 }
1438 }
1439
1440 skb_reset_network_header(frame);
1441 frame->dev = dev;
1442 frame->priority = skb->priority;
1443 rx->skb = frame;
1444
1445 payload = frame->data;
1446 ethertype = (payload[6] << 8) | payload[7];
1447
1448 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1449 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1450 compare_ether_addr(payload,
1451 bridge_tunnel_header) == 0)) {
1452 /* remove RFC1042 or Bridge-Tunnel
1453 * encapsulation and replace EtherType */
1454 skb_pull(frame, 6);
1455 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1456 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1457 } else {
1458 memcpy(skb_push(frame, sizeof(__be16)),
1459 &len, sizeof(__be16));
1460 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1461 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1462 }
1463
1464 if (!ieee80211_frame_allowed(rx, fc)) {
1465 if (skb == frame) /* last frame */
1466 return RX_DROP_UNUSABLE;
1467 dev_kfree_skb(frame);
1468 continue;
1469 }
1470
1471 ieee80211_deliver_skb(rx);
1472 }
1473
1474 return RX_QUEUED;
1475 }
1476
1477 #ifdef CONFIG_MAC80211_MESH
1478 static ieee80211_rx_result
1479 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1480 {
1481 struct ieee80211_hdr *hdr;
1482 struct ieee80211s_hdr *mesh_hdr;
1483 unsigned int hdrlen;
1484 struct sk_buff *skb = rx->skb, *fwd_skb;
1485 struct ieee80211_local *local = rx->local;
1486 struct ieee80211_sub_if_data *sdata;
1487
1488 hdr = (struct ieee80211_hdr *) skb->data;
1489 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1490 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1491 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1492
1493 if (!ieee80211_is_data(hdr->frame_control))
1494 return RX_CONTINUE;
1495
1496 if (!mesh_hdr->ttl)
1497 /* illegal frame */
1498 return RX_DROP_MONITOR;
1499
1500 if (mesh_hdr->flags & MESH_FLAGS_AE) {
1501 struct mesh_path *mppath;
1502 char *proxied_addr;
1503 char *mpp_addr;
1504
1505 if (is_multicast_ether_addr(hdr->addr1)) {
1506 mpp_addr = hdr->addr3;
1507 proxied_addr = mesh_hdr->eaddr1;
1508 } else {
1509 mpp_addr = hdr->addr4;
1510 proxied_addr = mesh_hdr->eaddr2;
1511 }
1512
1513 rcu_read_lock();
1514 mppath = mpp_path_lookup(proxied_addr, sdata);
1515 if (!mppath) {
1516 mpp_path_add(proxied_addr, mpp_addr, sdata);
1517 } else {
1518 spin_lock_bh(&mppath->state_lock);
1519 mppath->exp_time = jiffies;
1520 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1521 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1522 spin_unlock_bh(&mppath->state_lock);
1523 }
1524 rcu_read_unlock();
1525 }
1526
1527 /* Frame has reached destination. Don't forward */
1528 if (!is_multicast_ether_addr(hdr->addr1) &&
1529 compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1530 return RX_CONTINUE;
1531
1532 mesh_hdr->ttl--;
1533
1534 if (rx->flags & IEEE80211_RX_RA_MATCH) {
1535 if (!mesh_hdr->ttl)
1536 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1537 dropped_frames_ttl);
1538 else {
1539 struct ieee80211_hdr *fwd_hdr;
1540 struct ieee80211_tx_info *info;
1541
1542 fwd_skb = skb_copy(skb, GFP_ATOMIC);
1543
1544 if (!fwd_skb && net_ratelimit())
1545 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1546 rx->dev->name);
1547
1548 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
1549 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1550 info = IEEE80211_SKB_CB(fwd_skb);
1551 memset(info, 0, sizeof(*info));
1552 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1553 info->control.vif = &rx->sdata->vif;
1554 ieee80211_select_queue(local, fwd_skb);
1555 if (is_multicast_ether_addr(fwd_hdr->addr1))
1556 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1557 fwded_mcast);
1558 else {
1559 int err;
1560 /*
1561 * Save TA to addr1 to send TA a path error if a
1562 * suitable next hop is not found
1563 */
1564 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1565 ETH_ALEN);
1566 err = mesh_nexthop_lookup(fwd_skb, sdata);
1567 /* Failed to immediately resolve next hop:
1568 * fwded frame was dropped or will be added
1569 * later to the pending skb queue. */
1570 if (err)
1571 return RX_DROP_MONITOR;
1572
1573 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1574 fwded_unicast);
1575 }
1576 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1577 fwded_frames);
1578 ieee80211_add_pending_skb(local, fwd_skb);
1579 }
1580 }
1581
1582 if (is_multicast_ether_addr(hdr->addr1) ||
1583 rx->dev->flags & IFF_PROMISC)
1584 return RX_CONTINUE;
1585 else
1586 return RX_DROP_MONITOR;
1587 }
1588 #endif
1589
1590 static ieee80211_rx_result debug_noinline
1591 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1592 {
1593 struct net_device *dev = rx->dev;
1594 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1595 __le16 fc = hdr->frame_control;
1596 int err;
1597
1598 if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1599 return RX_CONTINUE;
1600
1601 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1602 return RX_DROP_MONITOR;
1603
1604 err = __ieee80211_data_to_8023(rx);
1605 if (unlikely(err))
1606 return RX_DROP_UNUSABLE;
1607
1608 if (!ieee80211_frame_allowed(rx, fc))
1609 return RX_DROP_MONITOR;
1610
1611 rx->skb->dev = dev;
1612
1613 dev->stats.rx_packets++;
1614 dev->stats.rx_bytes += rx->skb->len;
1615
1616 ieee80211_deliver_skb(rx);
1617
1618 return RX_QUEUED;
1619 }
1620
1621 static ieee80211_rx_result debug_noinline
1622 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1623 {
1624 struct ieee80211_local *local = rx->local;
1625 struct ieee80211_hw *hw = &local->hw;
1626 struct sk_buff *skb = rx->skb;
1627 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1628 struct tid_ampdu_rx *tid_agg_rx;
1629 u16 start_seq_num;
1630 u16 tid;
1631
1632 if (likely(!ieee80211_is_ctl(bar->frame_control)))
1633 return RX_CONTINUE;
1634
1635 if (ieee80211_is_back_req(bar->frame_control)) {
1636 if (!rx->sta)
1637 return RX_CONTINUE;
1638 tid = le16_to_cpu(bar->control) >> 12;
1639 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1640 != HT_AGG_STATE_OPERATIONAL)
1641 return RX_CONTINUE;
1642 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1643
1644 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1645
1646 /* reset session timer */
1647 if (tid_agg_rx->timeout)
1648 mod_timer(&tid_agg_rx->session_timer,
1649 TU_TO_EXP_TIME(tid_agg_rx->timeout));
1650
1651 /* manage reordering buffer according to requested */
1652 /* sequence number */
1653 rcu_read_lock();
1654 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1655 start_seq_num, 1);
1656 rcu_read_unlock();
1657 return RX_DROP_UNUSABLE;
1658 }
1659
1660 return RX_CONTINUE;
1661 }
1662
1663 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1664 struct ieee80211_mgmt *mgmt,
1665 size_t len)
1666 {
1667 struct ieee80211_local *local = sdata->local;
1668 struct sk_buff *skb;
1669 struct ieee80211_mgmt *resp;
1670
1671 if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1672 /* Not to own unicast address */
1673 return;
1674 }
1675
1676 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1677 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1678 /* Not from the current AP or not associated yet. */
1679 return;
1680 }
1681
1682 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1683 /* Too short SA Query request frame */
1684 return;
1685 }
1686
1687 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1688 if (skb == NULL)
1689 return;
1690
1691 skb_reserve(skb, local->hw.extra_tx_headroom);
1692 resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1693 memset(resp, 0, 24);
1694 memcpy(resp->da, mgmt->sa, ETH_ALEN);
1695 memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1696 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1697 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1698 IEEE80211_STYPE_ACTION);
1699 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1700 resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1701 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1702 memcpy(resp->u.action.u.sa_query.trans_id,
1703 mgmt->u.action.u.sa_query.trans_id,
1704 WLAN_SA_QUERY_TR_ID_LEN);
1705
1706 ieee80211_tx_skb(sdata, skb, 1);
1707 }
1708
1709 static ieee80211_rx_result debug_noinline
1710 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1711 {
1712 struct ieee80211_local *local = rx->local;
1713 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1714 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1715 int len = rx->skb->len;
1716
1717 if (!ieee80211_is_action(mgmt->frame_control))
1718 return RX_CONTINUE;
1719
1720 if (!rx->sta)
1721 return RX_DROP_MONITOR;
1722
1723 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1724 return RX_DROP_MONITOR;
1725
1726 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1727 return RX_DROP_MONITOR;
1728
1729 /* all categories we currently handle have action_code */
1730 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1731 return RX_DROP_MONITOR;
1732
1733 switch (mgmt->u.action.category) {
1734 case WLAN_CATEGORY_BACK:
1735 /*
1736 * The aggregation code is not prepared to handle
1737 * anything but STA/AP due to the BSSID handling;
1738 * IBSS could work in the code but isn't supported
1739 * by drivers or the standard.
1740 */
1741 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1742 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1743 sdata->vif.type != NL80211_IFTYPE_AP)
1744 return RX_DROP_MONITOR;
1745
1746 switch (mgmt->u.action.u.addba_req.action_code) {
1747 case WLAN_ACTION_ADDBA_REQ:
1748 if (len < (IEEE80211_MIN_ACTION_SIZE +
1749 sizeof(mgmt->u.action.u.addba_req)))
1750 return RX_DROP_MONITOR;
1751 ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1752 break;
1753 case WLAN_ACTION_ADDBA_RESP:
1754 if (len < (IEEE80211_MIN_ACTION_SIZE +
1755 sizeof(mgmt->u.action.u.addba_resp)))
1756 return RX_DROP_MONITOR;
1757 ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1758 break;
1759 case WLAN_ACTION_DELBA:
1760 if (len < (IEEE80211_MIN_ACTION_SIZE +
1761 sizeof(mgmt->u.action.u.delba)))
1762 return RX_DROP_MONITOR;
1763 ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1764 break;
1765 }
1766 break;
1767 case WLAN_CATEGORY_SPECTRUM_MGMT:
1768 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1769 return RX_DROP_MONITOR;
1770
1771 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1772 return RX_DROP_MONITOR;
1773
1774 switch (mgmt->u.action.u.measurement.action_code) {
1775 case WLAN_ACTION_SPCT_MSR_REQ:
1776 if (len < (IEEE80211_MIN_ACTION_SIZE +
1777 sizeof(mgmt->u.action.u.measurement)))
1778 return RX_DROP_MONITOR;
1779 ieee80211_process_measurement_req(sdata, mgmt, len);
1780 break;
1781 case WLAN_ACTION_SPCT_CHL_SWITCH:
1782 if (len < (IEEE80211_MIN_ACTION_SIZE +
1783 sizeof(mgmt->u.action.u.chan_switch)))
1784 return RX_DROP_MONITOR;
1785
1786 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1787 return RX_DROP_MONITOR;
1788
1789 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1790 return RX_DROP_MONITOR;
1791
1792 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1793 }
1794 break;
1795 case WLAN_CATEGORY_SA_QUERY:
1796 if (len < (IEEE80211_MIN_ACTION_SIZE +
1797 sizeof(mgmt->u.action.u.sa_query)))
1798 return RX_DROP_MONITOR;
1799 switch (mgmt->u.action.u.sa_query.action) {
1800 case WLAN_ACTION_SA_QUERY_REQUEST:
1801 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1802 return RX_DROP_MONITOR;
1803 ieee80211_process_sa_query_req(sdata, mgmt, len);
1804 break;
1805 case WLAN_ACTION_SA_QUERY_RESPONSE:
1806 /*
1807 * SA Query response is currently only used in AP mode
1808 * and it is processed in user space.
1809 */
1810 return RX_CONTINUE;
1811 }
1812 break;
1813 default:
1814 return RX_CONTINUE;
1815 }
1816
1817 rx->sta->rx_packets++;
1818 dev_kfree_skb(rx->skb);
1819 return RX_QUEUED;
1820 }
1821
1822 static ieee80211_rx_result debug_noinline
1823 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1824 {
1825 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1826 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1827
1828 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1829 return RX_DROP_MONITOR;
1830
1831 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1832 return RX_DROP_MONITOR;
1833
1834 if (ieee80211_vif_is_mesh(&sdata->vif))
1835 return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
1836
1837 if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1838 return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
1839
1840 if (sdata->vif.type == NL80211_IFTYPE_STATION)
1841 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1842
1843 return RX_DROP_MONITOR;
1844 }
1845
1846 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
1847 struct ieee80211_rx_data *rx)
1848 {
1849 int keyidx;
1850 unsigned int hdrlen;
1851
1852 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1853 if (rx->skb->len >= hdrlen + 4)
1854 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1855 else
1856 keyidx = -1;
1857
1858 if (!rx->sta) {
1859 /*
1860 * Some hardware seem to generate incorrect Michael MIC
1861 * reports; ignore them to avoid triggering countermeasures.
1862 */
1863 goto ignore;
1864 }
1865
1866 if (!ieee80211_has_protected(hdr->frame_control))
1867 goto ignore;
1868
1869 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1870 /*
1871 * APs with pairwise keys should never receive Michael MIC
1872 * errors for non-zero keyidx because these are reserved for
1873 * group keys and only the AP is sending real multicast
1874 * frames in the BSS.
1875 */
1876 goto ignore;
1877 }
1878
1879 if (!ieee80211_is_data(hdr->frame_control) &&
1880 !ieee80211_is_auth(hdr->frame_control))
1881 goto ignore;
1882
1883 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
1884 GFP_ATOMIC);
1885 ignore:
1886 dev_kfree_skb(rx->skb);
1887 rx->skb = NULL;
1888 }
1889
1890 /* TODO: use IEEE80211_RX_FRAGMENTED */
1891 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1892 {
1893 struct ieee80211_sub_if_data *sdata;
1894 struct ieee80211_local *local = rx->local;
1895 struct ieee80211_rtap_hdr {
1896 struct ieee80211_radiotap_header hdr;
1897 u8 flags;
1898 u8 rate;
1899 __le16 chan_freq;
1900 __le16 chan_flags;
1901 } __attribute__ ((packed)) *rthdr;
1902 struct sk_buff *skb = rx->skb, *skb2;
1903 struct net_device *prev_dev = NULL;
1904 struct ieee80211_rx_status *status = rx->status;
1905
1906 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1907 goto out_free_skb;
1908
1909 if (skb_headroom(skb) < sizeof(*rthdr) &&
1910 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1911 goto out_free_skb;
1912
1913 rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1914 memset(rthdr, 0, sizeof(*rthdr));
1915 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1916 rthdr->hdr.it_present =
1917 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1918 (1 << IEEE80211_RADIOTAP_RATE) |
1919 (1 << IEEE80211_RADIOTAP_CHANNEL));
1920
1921 rthdr->rate = rx->rate->bitrate / 5;
1922 rthdr->chan_freq = cpu_to_le16(status->freq);
1923
1924 if (status->band == IEEE80211_BAND_5GHZ)
1925 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1926 IEEE80211_CHAN_5GHZ);
1927 else
1928 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1929 IEEE80211_CHAN_2GHZ);
1930
1931 skb_set_mac_header(skb, 0);
1932 skb->ip_summed = CHECKSUM_UNNECESSARY;
1933 skb->pkt_type = PACKET_OTHERHOST;
1934 skb->protocol = htons(ETH_P_802_2);
1935
1936 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1937 if (!netif_running(sdata->dev))
1938 continue;
1939
1940 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1941 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1942 continue;
1943
1944 if (prev_dev) {
1945 skb2 = skb_clone(skb, GFP_ATOMIC);
1946 if (skb2) {
1947 skb2->dev = prev_dev;
1948 netif_rx(skb2);
1949 }
1950 }
1951
1952 prev_dev = sdata->dev;
1953 sdata->dev->stats.rx_packets++;
1954 sdata->dev->stats.rx_bytes += skb->len;
1955 }
1956
1957 if (prev_dev) {
1958 skb->dev = prev_dev;
1959 netif_rx(skb);
1960 skb = NULL;
1961 } else
1962 goto out_free_skb;
1963
1964 rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1965 return;
1966
1967 out_free_skb:
1968 dev_kfree_skb(skb);
1969 }
1970
1971
1972 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1973 struct ieee80211_rx_data *rx,
1974 struct sk_buff *skb)
1975 {
1976 ieee80211_rx_result res = RX_DROP_MONITOR;
1977
1978 rx->skb = skb;
1979 rx->sdata = sdata;
1980 rx->dev = sdata->dev;
1981
1982 #define CALL_RXH(rxh) \
1983 do { \
1984 res = rxh(rx); \
1985 if (res != RX_CONTINUE) \
1986 goto rxh_done; \
1987 } while (0);
1988
1989 CALL_RXH(ieee80211_rx_h_passive_scan)
1990 CALL_RXH(ieee80211_rx_h_check)
1991 CALL_RXH(ieee80211_rx_h_decrypt)
1992 CALL_RXH(ieee80211_rx_h_check_more_data)
1993 CALL_RXH(ieee80211_rx_h_sta_process)
1994 CALL_RXH(ieee80211_rx_h_defragment)
1995 CALL_RXH(ieee80211_rx_h_ps_poll)
1996 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1997 /* must be after MMIC verify so header is counted in MPDU mic */
1998 CALL_RXH(ieee80211_rx_h_remove_qos_control)
1999 CALL_RXH(ieee80211_rx_h_amsdu)
2000 #ifdef CONFIG_MAC80211_MESH
2001 if (ieee80211_vif_is_mesh(&sdata->vif))
2002 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2003 #endif
2004 CALL_RXH(ieee80211_rx_h_data)
2005 CALL_RXH(ieee80211_rx_h_ctrl)
2006 CALL_RXH(ieee80211_rx_h_action)
2007 CALL_RXH(ieee80211_rx_h_mgmt)
2008
2009 #undef CALL_RXH
2010
2011 rxh_done:
2012 switch (res) {
2013 case RX_DROP_MONITOR:
2014 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2015 if (rx->sta)
2016 rx->sta->rx_dropped++;
2017 /* fall through */
2018 case RX_CONTINUE:
2019 ieee80211_rx_cooked_monitor(rx);
2020 break;
2021 case RX_DROP_UNUSABLE:
2022 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2023 if (rx->sta)
2024 rx->sta->rx_dropped++;
2025 dev_kfree_skb(rx->skb);
2026 break;
2027 case RX_QUEUED:
2028 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2029 break;
2030 }
2031 }
2032
2033 /* main receive path */
2034
2035 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2036 struct ieee80211_rx_data *rx,
2037 struct ieee80211_hdr *hdr)
2038 {
2039 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2040 int multicast = is_multicast_ether_addr(hdr->addr1);
2041
2042 switch (sdata->vif.type) {
2043 case NL80211_IFTYPE_STATION:
2044 if (!bssid)
2045 return 0;
2046 if (!multicast &&
2047 compare_ether_addr(sdata->dev->dev_addr, hdr->addr1) != 0) {
2048 if (!(sdata->dev->flags & IFF_PROMISC))
2049 return 0;
2050 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2051 }
2052 break;
2053 case NL80211_IFTYPE_ADHOC:
2054 if (!bssid)
2055 return 0;
2056 if (ieee80211_is_beacon(hdr->frame_control)) {
2057 return 1;
2058 }
2059 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2060 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2061 return 0;
2062 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2063 } else if (!multicast &&
2064 compare_ether_addr(sdata->dev->dev_addr,
2065 hdr->addr1) != 0) {
2066 if (!(sdata->dev->flags & IFF_PROMISC))
2067 return 0;
2068 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2069 } else if (!rx->sta) {
2070 int rate_idx;
2071 if (rx->status->flag & RX_FLAG_HT)
2072 rate_idx = 0; /* TODO: HT rates */
2073 else
2074 rate_idx = rx->status->rate_idx;
2075 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2076 BIT(rate_idx));
2077 }
2078 break;
2079 case NL80211_IFTYPE_MESH_POINT:
2080 if (!multicast &&
2081 compare_ether_addr(sdata->dev->dev_addr,
2082 hdr->addr1) != 0) {
2083 if (!(sdata->dev->flags & IFF_PROMISC))
2084 return 0;
2085
2086 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2087 }
2088 break;
2089 case NL80211_IFTYPE_AP_VLAN:
2090 case NL80211_IFTYPE_AP:
2091 if (!bssid) {
2092 if (compare_ether_addr(sdata->dev->dev_addr,
2093 hdr->addr1))
2094 return 0;
2095 } else if (!ieee80211_bssid_match(bssid,
2096 sdata->dev->dev_addr)) {
2097 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2098 return 0;
2099 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2100 }
2101 break;
2102 case NL80211_IFTYPE_WDS:
2103 if (bssid || !ieee80211_is_data(hdr->frame_control))
2104 return 0;
2105 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2106 return 0;
2107 break;
2108 case NL80211_IFTYPE_MONITOR:
2109 /* take everything */
2110 break;
2111 case NL80211_IFTYPE_UNSPECIFIED:
2112 case __NL80211_IFTYPE_AFTER_LAST:
2113 /* should never get here */
2114 WARN_ON(1);
2115 break;
2116 }
2117
2118 return 1;
2119 }
2120
2121 /*
2122 * This is the actual Rx frames handler. as it blongs to Rx path it must
2123 * be called with rcu_read_lock protection.
2124 */
2125 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2126 struct sk_buff *skb,
2127 struct ieee80211_rate *rate)
2128 {
2129 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2130 struct ieee80211_local *local = hw_to_local(hw);
2131 struct ieee80211_sub_if_data *sdata;
2132 struct ieee80211_hdr *hdr;
2133 struct ieee80211_rx_data rx;
2134 int prepares;
2135 struct ieee80211_sub_if_data *prev = NULL;
2136 struct sk_buff *skb_new;
2137
2138 hdr = (struct ieee80211_hdr *)skb->data;
2139 memset(&rx, 0, sizeof(rx));
2140 rx.skb = skb;
2141 rx.local = local;
2142
2143 rx.status = status;
2144 rx.rate = rate;
2145
2146 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2147 local->dot11ReceivedFragmentCount++;
2148
2149 rx.sta = sta_info_get(local, hdr->addr2);
2150 if (rx.sta) {
2151 rx.sdata = rx.sta->sdata;
2152 rx.dev = rx.sta->sdata->dev;
2153 }
2154
2155 if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2156 ieee80211_rx_michael_mic_report(hdr, &rx);
2157 return;
2158 }
2159
2160 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2161 test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2162 rx.flags |= IEEE80211_RX_IN_SCAN;
2163
2164 ieee80211_parse_qos(&rx);
2165 ieee80211_verify_alignment(&rx);
2166
2167 skb = rx.skb;
2168
2169 if (rx.sdata && ieee80211_is_data(hdr->frame_control)) {
2170 rx.flags |= IEEE80211_RX_RA_MATCH;
2171 prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2172 if (prepares)
2173 prev = rx.sdata;
2174 } else list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2175 if (!netif_running(sdata->dev))
2176 continue;
2177
2178 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2179 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2180 continue;
2181
2182 rx.flags |= IEEE80211_RX_RA_MATCH;
2183 prepares = prepare_for_handlers(sdata, &rx, hdr);
2184
2185 if (!prepares)
2186 continue;
2187
2188 /*
2189 * frame is destined for this interface, but if it's not
2190 * also for the previous one we handle that after the
2191 * loop to avoid copying the SKB once too much
2192 */
2193
2194 if (!prev) {
2195 prev = sdata;
2196 continue;
2197 }
2198
2199 /*
2200 * frame was destined for the previous interface
2201 * so invoke RX handlers for it
2202 */
2203
2204 skb_new = skb_copy(skb, GFP_ATOMIC);
2205 if (!skb_new) {
2206 if (net_ratelimit())
2207 printk(KERN_DEBUG "%s: failed to copy "
2208 "multicast frame for %s\n",
2209 wiphy_name(local->hw.wiphy),
2210 prev->dev->name);
2211 continue;
2212 }
2213 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2214 prev = sdata;
2215 }
2216 if (prev)
2217 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2218 else
2219 dev_kfree_skb(skb);
2220 }
2221
2222 #define SEQ_MODULO 0x1000
2223 #define SEQ_MASK 0xfff
2224
2225 static inline int seq_less(u16 sq1, u16 sq2)
2226 {
2227 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2228 }
2229
2230 static inline u16 seq_inc(u16 sq)
2231 {
2232 return (sq + 1) & SEQ_MASK;
2233 }
2234
2235 static inline u16 seq_sub(u16 sq1, u16 sq2)
2236 {
2237 return (sq1 - sq2) & SEQ_MASK;
2238 }
2239
2240
2241 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
2242 struct tid_ampdu_rx *tid_agg_rx,
2243 int index)
2244 {
2245 struct ieee80211_supported_band *sband;
2246 struct ieee80211_rate *rate;
2247 struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
2248 struct ieee80211_rx_status *status;
2249
2250 if (!skb)
2251 goto no_frame;
2252
2253 status = IEEE80211_SKB_RXCB(skb);
2254
2255 /* release the reordered frames to stack */
2256 sband = hw->wiphy->bands[status->band];
2257 if (status->flag & RX_FLAG_HT)
2258 rate = sband->bitrates; /* TODO: HT rates */
2259 else
2260 rate = &sband->bitrates[status->rate_idx];
2261 __ieee80211_rx_handle_packet(hw, skb, rate);
2262 tid_agg_rx->stored_mpdu_num--;
2263 tid_agg_rx->reorder_buf[index] = NULL;
2264
2265 no_frame:
2266 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2267 }
2268
2269
2270 /*
2271 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
2272 * the skb was added to the buffer longer than this time ago, the earlier
2273 * frames that have not yet been received are assumed to be lost and the skb
2274 * can be released for processing. This may also release other skb's from the
2275 * reorder buffer if there are no additional gaps between the frames.
2276 */
2277 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
2278
2279 /*
2280 * As it function blongs to Rx path it must be called with
2281 * the proper rcu_read_lock protection for its flow.
2282 */
2283 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2284 struct tid_ampdu_rx *tid_agg_rx,
2285 struct sk_buff *skb,
2286 u16 mpdu_seq_num,
2287 int bar_req)
2288 {
2289 u16 head_seq_num, buf_size;
2290 int index;
2291
2292 buf_size = tid_agg_rx->buf_size;
2293 head_seq_num = tid_agg_rx->head_seq_num;
2294
2295 /* frame with out of date sequence number */
2296 if (seq_less(mpdu_seq_num, head_seq_num)) {
2297 dev_kfree_skb(skb);
2298 return 1;
2299 }
2300
2301 /* if frame sequence number exceeds our buffering window size or
2302 * block Ack Request arrived - release stored frames */
2303 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2304 /* new head to the ordering buffer */
2305 if (bar_req)
2306 head_seq_num = mpdu_seq_num;
2307 else
2308 head_seq_num =
2309 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2310 /* release stored frames up to new head to stack */
2311 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2312 index = seq_sub(tid_agg_rx->head_seq_num,
2313 tid_agg_rx->ssn)
2314 % tid_agg_rx->buf_size;
2315 ieee80211_release_reorder_frame(hw, tid_agg_rx,
2316 index);
2317 }
2318 if (bar_req)
2319 return 1;
2320 }
2321
2322 /* now the new frame is always in the range of the reordering */
2323 /* buffer window */
2324 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2325 % tid_agg_rx->buf_size;
2326 /* check if we already stored this frame */
2327 if (tid_agg_rx->reorder_buf[index]) {
2328 dev_kfree_skb(skb);
2329 return 1;
2330 }
2331
2332 /* if arrived mpdu is in the right order and nothing else stored */
2333 /* release it immediately */
2334 if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2335 tid_agg_rx->stored_mpdu_num == 0) {
2336 tid_agg_rx->head_seq_num =
2337 seq_inc(tid_agg_rx->head_seq_num);
2338 return 0;
2339 }
2340
2341 /* put the frame in the reordering buffer */
2342 tid_agg_rx->reorder_buf[index] = skb;
2343 tid_agg_rx->reorder_time[index] = jiffies;
2344 tid_agg_rx->stored_mpdu_num++;
2345 /* release the buffer until next missing frame */
2346 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2347 % tid_agg_rx->buf_size;
2348 if (!tid_agg_rx->reorder_buf[index] &&
2349 tid_agg_rx->stored_mpdu_num > 1) {
2350 /*
2351 * No buffers ready to be released, but check whether any
2352 * frames in the reorder buffer have timed out.
2353 */
2354 int j;
2355 int skipped = 1;
2356 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
2357 j = (j + 1) % tid_agg_rx->buf_size) {
2358 if (tid_agg_rx->reorder_buf[j] == NULL) {
2359 skipped++;
2360 continue;
2361 }
2362 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
2363 HZ / 10))
2364 break;
2365
2366 #ifdef CONFIG_MAC80211_HT_DEBUG
2367 if (net_ratelimit())
2368 printk(KERN_DEBUG "%s: release an RX reorder "
2369 "frame due to timeout on earlier "
2370 "frames\n",
2371 wiphy_name(hw->wiphy));
2372 #endif
2373 ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
2374
2375 /*
2376 * Increment the head seq# also for the skipped slots.
2377 */
2378 tid_agg_rx->head_seq_num =
2379 (tid_agg_rx->head_seq_num + skipped) &
2380 SEQ_MASK;
2381 skipped = 0;
2382 }
2383 } else while (tid_agg_rx->reorder_buf[index]) {
2384 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
2385 index = seq_sub(tid_agg_rx->head_seq_num,
2386 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2387 }
2388 return 1;
2389 }
2390
2391 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2392 struct sk_buff *skb)
2393 {
2394 struct ieee80211_hw *hw = &local->hw;
2395 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2396 struct sta_info *sta;
2397 struct tid_ampdu_rx *tid_agg_rx;
2398 u16 sc;
2399 u16 mpdu_seq_num;
2400 u8 ret = 0;
2401 int tid;
2402
2403 sta = sta_info_get(local, hdr->addr2);
2404 if (!sta)
2405 return ret;
2406
2407 /* filter the QoS data rx stream according to
2408 * STA/TID and check if this STA/TID is on aggregation */
2409 if (!ieee80211_is_data_qos(hdr->frame_control))
2410 goto end_reorder;
2411
2412 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2413
2414 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2415 goto end_reorder;
2416
2417 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2418
2419 /* qos null data frames are excluded */
2420 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2421 goto end_reorder;
2422
2423 /* new un-ordered ampdu frame - process it */
2424
2425 /* reset session timer */
2426 if (tid_agg_rx->timeout)
2427 mod_timer(&tid_agg_rx->session_timer,
2428 TU_TO_EXP_TIME(tid_agg_rx->timeout));
2429
2430 /* if this mpdu is fragmented - terminate rx aggregation session */
2431 sc = le16_to_cpu(hdr->seq_ctrl);
2432 if (sc & IEEE80211_SCTL_FRAG) {
2433 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2434 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2435 ret = 1;
2436 goto end_reorder;
2437 }
2438
2439 /* according to mpdu sequence number deal with reordering buffer */
2440 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2441 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2442 mpdu_seq_num, 0);
2443 end_reorder:
2444 return ret;
2445 }
2446
2447 /*
2448 * This is the receive path handler. It is called by a low level driver when an
2449 * 802.11 MPDU is received from the hardware.
2450 */
2451 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2452 {
2453 struct ieee80211_local *local = hw_to_local(hw);
2454 struct ieee80211_rate *rate = NULL;
2455 struct ieee80211_supported_band *sband;
2456 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2457
2458 WARN_ON_ONCE(softirq_count() == 0);
2459
2460 if (WARN_ON(status->band < 0 ||
2461 status->band >= IEEE80211_NUM_BANDS))
2462 goto drop;
2463
2464 sband = local->hw.wiphy->bands[status->band];
2465 if (WARN_ON(!sband))
2466 goto drop;
2467
2468 /*
2469 * If we're suspending, it is possible although not too likely
2470 * that we'd be receiving frames after having already partially
2471 * quiesced the stack. We can't process such frames then since
2472 * that might, for example, cause stations to be added or other
2473 * driver callbacks be invoked.
2474 */
2475 if (unlikely(local->quiescing || local->suspended))
2476 goto drop;
2477
2478 /*
2479 * The same happens when we're not even started,
2480 * but that's worth a warning.
2481 */
2482 if (WARN_ON(!local->started))
2483 goto drop;
2484
2485 if (status->flag & RX_FLAG_HT) {
2486 /* rate_idx is MCS index */
2487 if (WARN_ON(status->rate_idx < 0 ||
2488 status->rate_idx >= 76))
2489 goto drop;
2490 /* HT rates are not in the table - use the highest legacy rate
2491 * for now since other parts of mac80211 may not yet be fully
2492 * MCS aware. */
2493 rate = &sband->bitrates[sband->n_bitrates - 1];
2494 } else {
2495 if (WARN_ON(status->rate_idx < 0 ||
2496 status->rate_idx >= sband->n_bitrates))
2497 goto drop;
2498 rate = &sband->bitrates[status->rate_idx];
2499 }
2500
2501 /*
2502 * key references and virtual interfaces are protected using RCU
2503 * and this requires that we are in a read-side RCU section during
2504 * receive processing
2505 */
2506 rcu_read_lock();
2507
2508 /*
2509 * Frames with failed FCS/PLCP checksum are not returned,
2510 * all other frames are returned without radiotap header
2511 * if it was previously present.
2512 * Also, frames with less than 16 bytes are dropped.
2513 */
2514 skb = ieee80211_rx_monitor(local, skb, rate);
2515 if (!skb) {
2516 rcu_read_unlock();
2517 return;
2518 }
2519
2520 /*
2521 * In theory, the block ack reordering should happen after duplicate
2522 * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
2523 * the call to ieee80211_rx_reorder_ampdu() should really be moved to
2524 * happen as a new RX handler between ieee80211_rx_h_check and
2525 * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
2526 * the time being, the call can be here since RX reorder buf processing
2527 * will implicitly skip duplicates. We could, in theory at least,
2528 * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
2529 * frames from other than operational channel), but that should not
2530 * happen in normal networks.
2531 */
2532 if (!ieee80211_rx_reorder_ampdu(local, skb))
2533 __ieee80211_rx_handle_packet(hw, skb, rate);
2534
2535 rcu_read_unlock();
2536
2537 return;
2538 drop:
2539 kfree_skb(skb);
2540 }
2541 EXPORT_SYMBOL(ieee80211_rx);
2542
2543 /* This is a version of the rx handler that can be called from hard irq
2544 * context. Post the skb on the queue and schedule the tasklet */
2545 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2546 {
2547 struct ieee80211_local *local = hw_to_local(hw);
2548
2549 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2550
2551 skb->pkt_type = IEEE80211_RX_MSG;
2552 skb_queue_tail(&local->skb_queue, skb);
2553 tasklet_schedule(&local->tasklet);
2554 }
2555 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree