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htcleo: add Cotulla's fixes for non-android touchscreen!
[htc-linux.git] / net / mac80211 / rx.c
blob16c6cdc6e8af363b8ffeda0e6f301dead6440c83
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 int rtap_len)
44 {
45 skb_pull(skb, rtap_len);
46
47 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
48 if (likely(skb->len > FCS_LEN))
49 skb_trim(skb, skb->len - FCS_LEN);
50 else {
51 /* driver bug */
52 WARN_ON(1);
53 dev_kfree_skb(skb);
54 skb = NULL;
55 }
56 }
57
58 return skb;
59 }
60
61 static inline int should_drop_frame(struct sk_buff *skb,
62 int present_fcs_len,
63 int radiotap_len)
64 {
65 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
66 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
67
68 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
69 return 1;
70 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
71 return 1;
72 if (ieee80211_is_ctl(hdr->frame_control) &&
73 !ieee80211_is_pspoll(hdr->frame_control) &&
74 !ieee80211_is_back_req(hdr->frame_control))
75 return 1;
76 return 0;
77 }
78
79 static int
80 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
81 struct ieee80211_rx_status *status)
82 {
83 int len;
84
85 /* always present fields */
86 len = sizeof(struct ieee80211_radiotap_header) + 9;
87
88 if (status->flag & RX_FLAG_TSFT)
89 len += 8;
90 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
91 len += 1;
92 if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
93 len += 1;
94
95 if (len & 1) /* padding for RX_FLAGS if necessary */
96 len++;
97
98 /* make sure radiotap starts at a naturally aligned address */
99 if (len % 8)
100 len = roundup(len, 8);
101
102 return len;
103 }
104
105 /*
106 * ieee80211_add_rx_radiotap_header - add radiotap header
107 *
108 * add a radiotap header containing all the fields which the hardware provided.
109 */
110 static void
111 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
112 struct sk_buff *skb,
113 struct ieee80211_rate *rate,
114 int rtap_len)
115 {
116 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
117 struct ieee80211_radiotap_header *rthdr;
118 unsigned char *pos;
119
120 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
121 memset(rthdr, 0, rtap_len);
122
123 /* radiotap header, set always present flags */
124 rthdr->it_present =
125 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
126 (1 << IEEE80211_RADIOTAP_CHANNEL) |
127 (1 << IEEE80211_RADIOTAP_ANTENNA) |
128 (1 << IEEE80211_RADIOTAP_RX_FLAGS));
129 rthdr->it_len = cpu_to_le16(rtap_len);
130
131 pos = (unsigned char *)(rthdr+1);
132
133 /* the order of the following fields is important */
134
135 /* IEEE80211_RADIOTAP_TSFT */
136 if (status->flag & RX_FLAG_TSFT) {
137 *(__le64 *)pos = cpu_to_le64(status->mactime);
138 rthdr->it_present |=
139 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
140 pos += 8;
141 }
142
143 /* IEEE80211_RADIOTAP_FLAGS */
144 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
145 *pos |= IEEE80211_RADIOTAP_F_FCS;
146 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
147 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
148 if (status->flag & RX_FLAG_SHORTPRE)
149 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
150 pos++;
151
152 /* IEEE80211_RADIOTAP_RATE */
153 if (status->flag & RX_FLAG_HT) {
154 /*
155 * TODO: add following information into radiotap header once
156 * suitable fields are defined for it:
157 * - MCS index (status->rate_idx)
158 * - HT40 (status->flag & RX_FLAG_40MHZ)
159 * - short-GI (status->flag & RX_FLAG_SHORT_GI)
160 */
161 *pos = 0;
162 } else {
163 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
164 *pos = rate->bitrate / 5;
165 }
166 pos++;
167
168 /* IEEE80211_RADIOTAP_CHANNEL */
169 *(__le16 *)pos = cpu_to_le16(status->freq);
170 pos += 2;
171 if (status->band == IEEE80211_BAND_5GHZ)
172 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
173 IEEE80211_CHAN_5GHZ);
174 else if (rate->flags & IEEE80211_RATE_ERP_G)
175 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
176 IEEE80211_CHAN_2GHZ);
177 else
178 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
179 IEEE80211_CHAN_2GHZ);
180 pos += 2;
181
182 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
183 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
184 *pos = status->signal;
185 rthdr->it_present |=
186 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
187 pos++;
188 }
189
190 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
191 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
192 *pos = status->noise;
193 rthdr->it_present |=
194 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
195 pos++;
196 }
197
198 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
199
200 /* IEEE80211_RADIOTAP_ANTENNA */
201 *pos = status->antenna;
202 pos++;
203
204 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
205
206 /* IEEE80211_RADIOTAP_RX_FLAGS */
207 /* ensure 2 byte alignment for the 2 byte field as required */
208 if ((pos - (unsigned char *)rthdr) & 1)
209 pos++;
210 if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
211 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
212 pos += 2;
213 }
214
215 /*
216 * This function copies a received frame to all monitor interfaces and
217 * returns a cleaned-up SKB that no longer includes the FCS nor the
218 * radiotap header the driver might have added.
219 */
220 static struct sk_buff *
221 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
222 struct ieee80211_rate *rate)
223 {
224 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
225 struct ieee80211_sub_if_data *sdata;
226 int needed_headroom = 0;
227 struct sk_buff *skb, *skb2;
228 struct net_device *prev_dev = NULL;
229 int present_fcs_len = 0;
230 int rtap_len = 0;
231
232 /*
233 * First, we may need to make a copy of the skb because
234 * (1) we need to modify it for radiotap (if not present), and
235 * (2) the other RX handlers will modify the skb we got.
236 *
237 * We don't need to, of course, if we aren't going to return
238 * the SKB because it has a bad FCS/PLCP checksum.
239 */
240 if (status->flag & RX_FLAG_RADIOTAP)
241 rtap_len = ieee80211_get_radiotap_len(origskb->data);
242 else
243 /* room for the radiotap header based on driver features */
244 needed_headroom = ieee80211_rx_radiotap_len(local, status);
245
246 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
247 present_fcs_len = FCS_LEN;
248
249 if (!local->monitors) {
250 if (should_drop_frame(origskb, present_fcs_len, rtap_len)) {
251 dev_kfree_skb(origskb);
252 return NULL;
253 }
254
255 return remove_monitor_info(local, origskb, rtap_len);
256 }
257
258 if (should_drop_frame(origskb, present_fcs_len, rtap_len)) {
259 /* only need to expand headroom if necessary */
260 skb = origskb;
261 origskb = NULL;
262
263 /*
264 * This shouldn't trigger often because most devices have an
265 * RX header they pull before we get here, and that should
266 * be big enough for our radiotap information. We should
267 * probably export the length to drivers so that we can have
268 * them allocate enough headroom to start with.
269 */
270 if (skb_headroom(skb) < needed_headroom &&
271 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
272 dev_kfree_skb(skb);
273 return NULL;
274 }
275 } else {
276 /*
277 * Need to make a copy and possibly remove radiotap header
278 * and FCS from the original.
279 */
280 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
281
282 origskb = remove_monitor_info(local, origskb, rtap_len);
283
284 if (!skb)
285 return origskb;
286 }
287
288 /* if necessary, prepend radiotap information */
289 if (!(status->flag & RX_FLAG_RADIOTAP))
290 ieee80211_add_rx_radiotap_header(local, skb, rate,
291 needed_headroom);
292
293 skb_reset_mac_header(skb);
294 skb->ip_summed = CHECKSUM_UNNECESSARY;
295 skb->pkt_type = PACKET_OTHERHOST;
296 skb->protocol = htons(ETH_P_802_2);
297
298 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
299 if (!netif_running(sdata->dev))
300 continue;
301
302 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
303 continue;
304
305 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
306 continue;
307
308 if (prev_dev) {
309 skb2 = skb_clone(skb, GFP_ATOMIC);
310 if (skb2) {
311 skb2->dev = prev_dev;
312 netif_rx(skb2);
313 }
314 }
315
316 prev_dev = sdata->dev;
317 sdata->dev->stats.rx_packets++;
318 sdata->dev->stats.rx_bytes += skb->len;
319 }
320
321 if (prev_dev) {
322 skb->dev = prev_dev;
323 netif_rx(skb);
324 } else
325 dev_kfree_skb(skb);
326
327 return origskb;
328 }
329
330
331 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
332 {
333 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
334 int tid;
335
336 /* does the frame have a qos control field? */
337 if (ieee80211_is_data_qos(hdr->frame_control)) {
338 u8 *qc = ieee80211_get_qos_ctl(hdr);
339 /* frame has qos control */
340 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
341 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
342 rx->flags |= IEEE80211_RX_AMSDU;
343 else
344 rx->flags &= ~IEEE80211_RX_AMSDU;
345 } else {
346 /*
347 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
348 *
349 * Sequence numbers for management frames, QoS data
350 * frames with a broadcast/multicast address in the
351 * Address 1 field, and all non-QoS data frames sent
352 * by QoS STAs are assigned using an additional single
353 * modulo-4096 counter, [...]
354 *
355 * We also use that counter for non-QoS STAs.
356 */
357 tid = NUM_RX_DATA_QUEUES - 1;
358 }
359
360 rx->queue = tid;
361 /* Set skb->priority to 1d tag if highest order bit of TID is not set.
362 * For now, set skb->priority to 0 for other cases. */
363 rx->skb->priority = (tid > 7) ? 0 : tid;
364 }
365
366 /**
367 * DOC: Packet alignment
368 *
369 * Drivers always need to pass packets that are aligned to two-byte boundaries
370 * to the stack.
371 *
372 * Additionally, should, if possible, align the payload data in a way that
373 * guarantees that the contained IP header is aligned to a four-byte
374 * boundary. In the case of regular frames, this simply means aligning the
375 * payload to a four-byte boundary (because either the IP header is directly
376 * contained, or IV/RFC1042 headers that have a length divisible by four are
377 * in front of it).
378 *
379 * With A-MSDU frames, however, the payload data address must yield two modulo
380 * four because there are 14-byte 802.3 headers within the A-MSDU frames that
381 * push the IP header further back to a multiple of four again. Thankfully, the
382 * specs were sane enough this time around to require padding each A-MSDU
383 * subframe to a length that is a multiple of four.
384 *
385 * Padding like Atheros hardware adds which is inbetween the 802.11 header and
386 * the payload is not supported, the driver is required to move the 802.11
387 * header to be directly in front of the payload in that case.
388 */
389 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
390 {
391 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
392 int hdrlen;
393
394 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
395 return;
396 #endif
397
398 if (WARN_ONCE((unsigned long)rx->skb->data & 1,
399 "unaligned packet at 0x%p\n", rx->skb->data))
400 return;
401
402 if (!ieee80211_is_data_present(hdr->frame_control))
403 return;
404
405 hdrlen = ieee80211_hdrlen(hdr->frame_control);
406 if (rx->flags & IEEE80211_RX_AMSDU)
407 hdrlen += ETH_HLEN;
408 WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
409 "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
410 }
411
412
413 /* rx handlers */
414
415 static ieee80211_rx_result debug_noinline
416 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
417 {
418 struct ieee80211_local *local = rx->local;
419 struct sk_buff *skb = rx->skb;
420
421 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
422 return ieee80211_scan_rx(rx->sdata, skb);
423
424 if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
425 (rx->flags & IEEE80211_RX_IN_SCAN))) {
426 /* drop all the other packets during a software scan anyway */
427 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
428 dev_kfree_skb(skb);
429 return RX_QUEUED;
430 }
431
432 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
433 /* scanning finished during invoking of handlers */
434 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
435 return RX_DROP_UNUSABLE;
436 }
437
438 return RX_CONTINUE;
439 }
440
441
442 static int ieee80211_is_unicast_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 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
454 {
455 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
456
457 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
458 return 0;
459
460 return ieee80211_is_robust_mgmt_frame(hdr);
461 }
462
463
464 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
465 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
466 {
467 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
468 struct ieee80211_mmie *mmie;
469
470 if (skb->len < 24 + sizeof(*mmie) ||
471 !is_multicast_ether_addr(hdr->da))
472 return -1;
473
474 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
475 return -1; /* not a robust management frame */
476
477 mmie = (struct ieee80211_mmie *)
478 (skb->data + skb->len - sizeof(*mmie));
479 if (mmie->element_id != WLAN_EID_MMIE ||
480 mmie->length != sizeof(*mmie) - 2)
481 return -1;
482
483 return le16_to_cpu(mmie->key_id);
484 }
485
486
487 static ieee80211_rx_result
488 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
489 {
490 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
491 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
492 char *dev_addr = rx->dev->dev_addr;
493
494 if (ieee80211_is_data(hdr->frame_control)) {
495 if (is_multicast_ether_addr(hdr->addr1)) {
496 if (ieee80211_has_tods(hdr->frame_control) ||
497 !ieee80211_has_fromds(hdr->frame_control))
498 return RX_DROP_MONITOR;
499 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
500 return RX_DROP_MONITOR;
501 } else {
502 if (!ieee80211_has_a4(hdr->frame_control))
503 return RX_DROP_MONITOR;
504 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
505 return RX_DROP_MONITOR;
506 }
507 }
508
509 /* If there is not an established peer link and this is not a peer link
510 * establisment frame, beacon or probe, drop the frame.
511 */
512
513 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
514 struct ieee80211_mgmt *mgmt;
515
516 if (!ieee80211_is_mgmt(hdr->frame_control))
517 return RX_DROP_MONITOR;
518
519 if (ieee80211_is_action(hdr->frame_control)) {
520 mgmt = (struct ieee80211_mgmt *)hdr;
521 if (mgmt->u.action.category != PLINK_CATEGORY)
522 return RX_DROP_MONITOR;
523 return RX_CONTINUE;
524 }
525
526 if (ieee80211_is_probe_req(hdr->frame_control) ||
527 ieee80211_is_probe_resp(hdr->frame_control) ||
528 ieee80211_is_beacon(hdr->frame_control))
529 return RX_CONTINUE;
530
531 return RX_DROP_MONITOR;
532
533 }
534
535 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
536
537 if (ieee80211_is_data(hdr->frame_control) &&
538 is_multicast_ether_addr(hdr->addr1) &&
539 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
540 return RX_DROP_MONITOR;
541 #undef msh_h_get
542
543 return RX_CONTINUE;
544 }
545
546
547 static ieee80211_rx_result debug_noinline
548 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
549 {
550 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
551
552 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
553 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
554 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
555 rx->sta->last_seq_ctrl[rx->queue] ==
556 hdr->seq_ctrl)) {
557 if (rx->flags & IEEE80211_RX_RA_MATCH) {
558 rx->local->dot11FrameDuplicateCount++;
559 rx->sta->num_duplicates++;
560 }
561 return RX_DROP_MONITOR;
562 } else
563 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
564 }
565
566 if (unlikely(rx->skb->len < 16)) {
567 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
568 return RX_DROP_MONITOR;
569 }
570
571 /* Drop disallowed frame classes based on STA auth/assoc state;
572 * IEEE 802.11, Chap 5.5.
573 *
574 * mac80211 filters only based on association state, i.e. it drops
575 * Class 3 frames from not associated stations. hostapd sends
576 * deauth/disassoc frames when needed. In addition, hostapd is
577 * responsible for filtering on both auth and assoc states.
578 */
579
580 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
581 return ieee80211_rx_mesh_check(rx);
582
583 if (unlikely((ieee80211_is_data(hdr->frame_control) ||
584 ieee80211_is_pspoll(hdr->frame_control)) &&
585 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
586 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
587 if ((!ieee80211_has_fromds(hdr->frame_control) &&
588 !ieee80211_has_tods(hdr->frame_control) &&
589 ieee80211_is_data(hdr->frame_control)) ||
590 !(rx->flags & IEEE80211_RX_RA_MATCH)) {
591 /* Drop IBSS frames and frames for other hosts
592 * silently. */
593 return RX_DROP_MONITOR;
594 }
595
596 return RX_DROP_MONITOR;
597 }
598
599 return RX_CONTINUE;
600 }
601
602
603 static ieee80211_rx_result debug_noinline
604 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
605 {
606 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
607 int keyidx;
608 int hdrlen;
609 ieee80211_rx_result result = RX_DROP_UNUSABLE;
610 struct ieee80211_key *stakey = NULL;
611 int mmie_keyidx = -1;
612
613 /*
614 * Key selection 101
615 *
616 * There are four types of keys:
617 * - GTK (group keys)
618 * - IGTK (group keys for management frames)
619 * - PTK (pairwise keys)
620 * - STK (station-to-station pairwise keys)
621 *
622 * When selecting a key, we have to distinguish between multicast
623 * (including broadcast) and unicast frames, the latter can only
624 * use PTKs and STKs while the former always use GTKs and IGTKs.
625 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
626 * unicast frames can also use key indices like GTKs. Hence, if we
627 * don't have a PTK/STK we check the key index for a WEP key.
628 *
629 * Note that in a regular BSS, multicast frames are sent by the
630 * AP only, associated stations unicast the frame to the AP first
631 * which then multicasts it on their behalf.
632 *
633 * There is also a slight problem in IBSS mode: GTKs are negotiated
634 * with each station, that is something we don't currently handle.
635 * The spec seems to expect that one negotiates the same key with
636 * every station but there's no such requirement; VLANs could be
637 * possible.
638 */
639
640 /*
641 * No point in finding a key and decrypting if the frame is neither
642 * addressed to us nor a multicast frame.
643 */
644 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
645 return RX_CONTINUE;
646
647 if (rx->sta)
648 stakey = rcu_dereference(rx->sta->key);
649
650 if (!ieee80211_has_protected(hdr->frame_control))
651 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
652
653 if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
654 rx->key = stakey;
655 /* Skip decryption if the frame is not protected. */
656 if (!ieee80211_has_protected(hdr->frame_control))
657 return RX_CONTINUE;
658 } else if (mmie_keyidx >= 0) {
659 /* Broadcast/multicast robust management frame / BIP */
660 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
661 (rx->status->flag & RX_FLAG_IV_STRIPPED))
662 return RX_CONTINUE;
663
664 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
665 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
666 return RX_DROP_MONITOR; /* unexpected BIP keyidx */
667 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
668 } else if (!ieee80211_has_protected(hdr->frame_control)) {
669 /*
670 * The frame was not protected, so skip decryption. However, we
671 * need to set rx->key if there is a key that could have been
672 * used so that the frame may be dropped if encryption would
673 * have been expected.
674 */
675 struct ieee80211_key *key = NULL;
676 if (ieee80211_is_mgmt(hdr->frame_control) &&
677 is_multicast_ether_addr(hdr->addr1) &&
678 (key = rcu_dereference(rx->sdata->default_mgmt_key)))
679 rx->key = key;
680 else if ((key = rcu_dereference(rx->sdata->default_key)))
681 rx->key = key;
682 return RX_CONTINUE;
683 } else {
684 /*
685 * The device doesn't give us the IV so we won't be
686 * able to look up the key. That's ok though, we
687 * don't need to decrypt the frame, we just won't
688 * be able to keep statistics accurate.
689 * Except for key threshold notifications, should
690 * we somehow allow the driver to tell us which key
691 * the hardware used if this flag is set?
692 */
693 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
694 (rx->status->flag & RX_FLAG_IV_STRIPPED))
695 return RX_CONTINUE;
696
697 hdrlen = ieee80211_hdrlen(hdr->frame_control);
698
699 if (rx->skb->len < 8 + hdrlen)
700 return RX_DROP_UNUSABLE; /* TODO: count this? */
701
702 /*
703 * no need to call ieee80211_wep_get_keyidx,
704 * it verifies a bunch of things we've done already
705 */
706 keyidx = rx->skb->data[hdrlen + 3] >> 6;
707
708 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
709
710 /*
711 * RSNA-protected unicast frames should always be sent with
712 * pairwise or station-to-station keys, but for WEP we allow
713 * using a key index as well.
714 */
715 if (rx->key && rx->key->conf.alg != ALG_WEP &&
716 !is_multicast_ether_addr(hdr->addr1))
717 rx->key = NULL;
718 }
719
720 if (rx->key) {
721 rx->key->tx_rx_count++;
722 /* TODO: add threshold stuff again */
723 } else {
724 return RX_DROP_MONITOR;
725 }
726
727 /* Check for weak IVs if possible */
728 if (rx->sta && rx->key->conf.alg == ALG_WEP &&
729 ieee80211_is_data(hdr->frame_control) &&
730 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
731 !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
732 ieee80211_wep_is_weak_iv(rx->skb, rx->key))
733 rx->sta->wep_weak_iv_count++;
734
735 switch (rx->key->conf.alg) {
736 case ALG_WEP:
737 result = ieee80211_crypto_wep_decrypt(rx);
738 break;
739 case ALG_TKIP:
740 result = ieee80211_crypto_tkip_decrypt(rx);
741 break;
742 case ALG_CCMP:
743 result = ieee80211_crypto_ccmp_decrypt(rx);
744 break;
745 case ALG_AES_CMAC:
746 result = ieee80211_crypto_aes_cmac_decrypt(rx);
747 break;
748 }
749
750 /* either the frame has been decrypted or will be dropped */
751 rx->status->flag |= RX_FLAG_DECRYPTED;
752
753 return result;
754 }
755
756 static ieee80211_rx_result debug_noinline
757 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
758 {
759 struct ieee80211_local *local;
760 struct ieee80211_hdr *hdr;
761 struct sk_buff *skb;
762
763 local = rx->local;
764 skb = rx->skb;
765 hdr = (struct ieee80211_hdr *) skb->data;
766
767 if (!local->pspolling)
768 return RX_CONTINUE;
769
770 if (!ieee80211_has_fromds(hdr->frame_control))
771 /* this is not from AP */
772 return RX_CONTINUE;
773
774 if (!ieee80211_is_data(hdr->frame_control))
775 return RX_CONTINUE;
776
777 if (!ieee80211_has_moredata(hdr->frame_control)) {
778 /* AP has no more frames buffered for us */
779 local->pspolling = false;
780 return RX_CONTINUE;
781 }
782
783 /* more data bit is set, let's request a new frame from the AP */
784 ieee80211_send_pspoll(local, rx->sdata);
785
786 return RX_CONTINUE;
787 }
788
789 static void ap_sta_ps_start(struct sta_info *sta)
790 {
791 struct ieee80211_sub_if_data *sdata = sta->sdata;
792 struct ieee80211_local *local = sdata->local;
793
794 atomic_inc(&sdata->bss->num_sta_ps);
795 set_sta_flags(sta, WLAN_STA_PS);
796 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
797 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
798 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
799 sdata->dev->name, sta->sta.addr, sta->sta.aid);
800 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
801 }
802
803 static int ap_sta_ps_end(struct sta_info *sta)
804 {
805 struct ieee80211_sub_if_data *sdata = sta->sdata;
806 struct ieee80211_local *local = sdata->local;
807 int sent, buffered;
808
809 atomic_dec(&sdata->bss->num_sta_ps);
810
811 clear_sta_flags(sta, WLAN_STA_PS);
812 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
813
814 if (!skb_queue_empty(&sta->ps_tx_buf))
815 sta_info_clear_tim_bit(sta);
816
817 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
818 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
819 sdata->dev->name, sta->sta.addr, sta->sta.aid);
820 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
821
822 /* Send all buffered frames to the station */
823 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
824 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf);
825 sent += buffered;
826 local->total_ps_buffered -= buffered;
827
828 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
829 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
830 "since STA not sleeping anymore\n", sdata->dev->name,
831 sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
832 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
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 /*
847 * Update last_rx only for IBSS packets which are for the current
848 * BSSID to avoid keeping the current IBSS network alive in cases
849 * where other STAs start using different BSSID.
850 */
851 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
852 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
853 NL80211_IFTYPE_ADHOC);
854 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
855 sta->last_rx = jiffies;
856 } else if (!is_multicast_ether_addr(hdr->addr1)) {
857 /*
858 * Mesh beacons will update last_rx when if they are found to
859 * match the current local configuration when processed.
860 */
861 sta->last_rx = jiffies;
862 }
863
864 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
865 return RX_CONTINUE;
866
867 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
868 ieee80211_sta_rx_notify(rx->sdata, hdr);
869
870 sta->rx_fragments++;
871 sta->rx_bytes += rx->skb->len;
872 sta->last_signal = rx->status->signal;
873 sta->last_qual = rx->status->qual;
874 sta->last_noise = rx->status->noise;
875
876 /*
877 * Change STA power saving mode only at the end of a frame
878 * exchange sequence.
879 */
880 if (!ieee80211_has_morefrags(hdr->frame_control) &&
881 (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
882 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
883 if (test_sta_flags(sta, WLAN_STA_PS)) {
884 /*
885 * Ignore doze->wake transitions that are
886 * indicated by non-data frames, the standard
887 * is unclear here, but for example going to
888 * PS mode and then scanning would cause a
889 * doze->wake transition for the probe request,
890 * and that is clearly undesirable.
891 */
892 if (ieee80211_is_data(hdr->frame_control) &&
893 !ieee80211_has_pm(hdr->frame_control))
894 rx->sent_ps_buffered += ap_sta_ps_end(sta);
895 } else {
896 if (ieee80211_has_pm(hdr->frame_control))
897 ap_sta_ps_start(sta);
898 }
899 }
900
901 /* Drop data::nullfunc frames silently, since they are used only to
902 * control station power saving mode. */
903 if (ieee80211_is_nullfunc(hdr->frame_control)) {
904 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
905 /* Update counter and free packet here to avoid counting this
906 * as a dropped packed. */
907 sta->rx_packets++;
908 dev_kfree_skb(rx->skb);
909 return RX_QUEUED;
910 }
911
912 return RX_CONTINUE;
913 } /* ieee80211_rx_h_sta_process */
914
915 static inline struct ieee80211_fragment_entry *
916 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
917 unsigned int frag, unsigned int seq, int rx_queue,
918 struct sk_buff **skb)
919 {
920 struct ieee80211_fragment_entry *entry;
921 int idx;
922
923 idx = sdata->fragment_next;
924 entry = &sdata->fragments[sdata->fragment_next++];
925 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
926 sdata->fragment_next = 0;
927
928 if (!skb_queue_empty(&entry->skb_list)) {
929 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
930 struct ieee80211_hdr *hdr =
931 (struct ieee80211_hdr *) entry->skb_list.next->data;
932 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
933 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
934 "addr1=%pM addr2=%pM\n",
935 sdata->dev->name, idx,
936 jiffies - entry->first_frag_time, entry->seq,
937 entry->last_frag, hdr->addr1, hdr->addr2);
938 #endif
939 __skb_queue_purge(&entry->skb_list);
940 }
941
942 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
943 *skb = NULL;
944 entry->first_frag_time = jiffies;
945 entry->seq = seq;
946 entry->rx_queue = rx_queue;
947 entry->last_frag = frag;
948 entry->ccmp = 0;
949 entry->extra_len = 0;
950
951 return entry;
952 }
953
954 static inline struct ieee80211_fragment_entry *
955 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
956 unsigned int frag, unsigned int seq,
957 int rx_queue, struct ieee80211_hdr *hdr)
958 {
959 struct ieee80211_fragment_entry *entry;
960 int i, idx;
961
962 idx = sdata->fragment_next;
963 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
964 struct ieee80211_hdr *f_hdr;
965
966 idx--;
967 if (idx < 0)
968 idx = IEEE80211_FRAGMENT_MAX - 1;
969
970 entry = &sdata->fragments[idx];
971 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
972 entry->rx_queue != rx_queue ||
973 entry->last_frag + 1 != frag)
974 continue;
975
976 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
977
978 /*
979 * Check ftype and addresses are equal, else check next fragment
980 */
981 if (((hdr->frame_control ^ f_hdr->frame_control) &
982 cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
983 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
984 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
985 continue;
986
987 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
988 __skb_queue_purge(&entry->skb_list);
989 continue;
990 }
991 return entry;
992 }
993
994 return NULL;
995 }
996
997 static ieee80211_rx_result debug_noinline
998 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
999 {
1000 struct ieee80211_hdr *hdr;
1001 u16 sc;
1002 __le16 fc;
1003 unsigned int frag, seq;
1004 struct ieee80211_fragment_entry *entry;
1005 struct sk_buff *skb;
1006
1007 hdr = (struct ieee80211_hdr *)rx->skb->data;
1008 fc = hdr->frame_control;
1009 sc = le16_to_cpu(hdr->seq_ctrl);
1010 frag = sc & IEEE80211_SCTL_FRAG;
1011
1012 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1013 (rx->skb)->len < 24 ||
1014 is_multicast_ether_addr(hdr->addr1))) {
1015 /* not fragmented */
1016 goto out;
1017 }
1018 I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1019
1020 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1021
1022 if (frag == 0) {
1023 /* This is the first fragment of a new frame. */
1024 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1025 rx->queue, &(rx->skb));
1026 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1027 ieee80211_has_protected(fc)) {
1028 /* Store CCMP PN so that we can verify that the next
1029 * fragment has a sequential PN value. */
1030 entry->ccmp = 1;
1031 memcpy(entry->last_pn,
1032 rx->key->u.ccmp.rx_pn[rx->queue],
1033 CCMP_PN_LEN);
1034 }
1035 return RX_QUEUED;
1036 }
1037
1038 /* This is a fragment for a frame that should already be pending in
1039 * fragment cache. Add this fragment to the end of the pending entry.
1040 */
1041 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1042 if (!entry) {
1043 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1044 return RX_DROP_MONITOR;
1045 }
1046
1047 /* Verify that MPDUs within one MSDU have sequential PN values.
1048 * (IEEE 802.11i, 8.3.3.4.5) */
1049 if (entry->ccmp) {
1050 int i;
1051 u8 pn[CCMP_PN_LEN], *rpn;
1052 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1053 return RX_DROP_UNUSABLE;
1054 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1055 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1056 pn[i]++;
1057 if (pn[i])
1058 break;
1059 }
1060 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1061 if (memcmp(pn, rpn, CCMP_PN_LEN))
1062 return RX_DROP_UNUSABLE;
1063 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1064 }
1065
1066 skb_pull(rx->skb, ieee80211_hdrlen(fc));
1067 __skb_queue_tail(&entry->skb_list, rx->skb);
1068 entry->last_frag = frag;
1069 entry->extra_len += rx->skb->len;
1070 if (ieee80211_has_morefrags(fc)) {
1071 rx->skb = NULL;
1072 return RX_QUEUED;
1073 }
1074
1075 rx->skb = __skb_dequeue(&entry->skb_list);
1076 if (skb_tailroom(rx->skb) < entry->extra_len) {
1077 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1078 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1079 GFP_ATOMIC))) {
1080 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1081 __skb_queue_purge(&entry->skb_list);
1082 return RX_DROP_UNUSABLE;
1083 }
1084 }
1085 while ((skb = __skb_dequeue(&entry->skb_list))) {
1086 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1087 dev_kfree_skb(skb);
1088 }
1089
1090 /* Complete frame has been reassembled - process it now */
1091 rx->flags |= IEEE80211_RX_FRAGMENTED;
1092
1093 out:
1094 if (rx->sta)
1095 rx->sta->rx_packets++;
1096 if (is_multicast_ether_addr(hdr->addr1))
1097 rx->local->dot11MulticastReceivedFrameCount++;
1098 else
1099 ieee80211_led_rx(rx->local);
1100 return RX_CONTINUE;
1101 }
1102
1103 static ieee80211_rx_result debug_noinline
1104 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1105 {
1106 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1107 struct sk_buff *skb;
1108 int no_pending_pkts;
1109 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1110
1111 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1112 !(rx->flags & IEEE80211_RX_RA_MATCH)))
1113 return RX_CONTINUE;
1114
1115 if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1116 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1117 return RX_DROP_UNUSABLE;
1118
1119 skb = skb_dequeue(&rx->sta->tx_filtered);
1120 if (!skb) {
1121 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1122 if (skb)
1123 rx->local->total_ps_buffered--;
1124 }
1125 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1126 skb_queue_empty(&rx->sta->ps_tx_buf);
1127
1128 if (skb) {
1129 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1130 struct ieee80211_hdr *hdr =
1131 (struct ieee80211_hdr *) skb->data;
1132
1133 /*
1134 * Tell TX path to send this frame even though the STA may
1135 * still remain is PS mode after this frame exchange.
1136 */
1137 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
1138
1139 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1140 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1141 rx->sta->sta.addr, rx->sta->sta.aid,
1142 skb_queue_len(&rx->sta->ps_tx_buf));
1143 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1144
1145 /* Use MoreData flag to indicate whether there are more
1146 * buffered frames for this STA */
1147 if (no_pending_pkts)
1148 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1149 else
1150 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1151
1152 ieee80211_add_pending_skb(rx->local, skb);
1153
1154 if (no_pending_pkts)
1155 sta_info_clear_tim_bit(rx->sta);
1156 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1157 } else if (!rx->sent_ps_buffered) {
1158 /*
1159 * FIXME: This can be the result of a race condition between
1160 * us expiring a frame and the station polling for it.
1161 * Should we send it a null-func frame indicating we
1162 * have nothing buffered for it?
1163 */
1164 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1165 "though there are no buffered frames for it\n",
1166 rx->dev->name, rx->sta->sta.addr);
1167 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1168 }
1169
1170 /* Free PS Poll skb here instead of returning RX_DROP that would
1171 * count as an dropped frame. */
1172 dev_kfree_skb(rx->skb);
1173
1174 return RX_QUEUED;
1175 }
1176
1177 static ieee80211_rx_result debug_noinline
1178 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1179 {
1180 u8 *data = rx->skb->data;
1181 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1182
1183 if (!ieee80211_is_data_qos(hdr->frame_control))
1184 return RX_CONTINUE;
1185
1186 /* remove the qos control field, update frame type and meta-data */
1187 memmove(data + IEEE80211_QOS_CTL_LEN, data,
1188 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1189 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1190 /* change frame type to non QOS */
1191 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1192
1193 return RX_CONTINUE;
1194 }
1195
1196 static int
1197 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1198 {
1199 if (unlikely(!rx->sta ||
1200 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1201 return -EACCES;
1202
1203 return 0;
1204 }
1205
1206 static int
1207 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1208 {
1209 /*
1210 * Pass through unencrypted frames if the hardware has
1211 * decrypted them already.
1212 */
1213 if (rx->status->flag & RX_FLAG_DECRYPTED)
1214 return 0;
1215
1216 /* Drop unencrypted frames if key is set. */
1217 if (unlikely(!ieee80211_has_protected(fc) &&
1218 !ieee80211_is_nullfunc(fc) &&
1219 ieee80211_is_data(fc) &&
1220 (rx->key || rx->sdata->drop_unencrypted)))
1221 return -EACCES;
1222 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1223 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1224 rx->key))
1225 return -EACCES;
1226 /* BIP does not use Protected field, so need to check MMIE */
1227 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
1228 && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1229 rx->key))
1230 return -EACCES;
1231 /*
1232 * When using MFP, Action frames are not allowed prior to
1233 * having configured keys.
1234 */
1235 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1236 ieee80211_is_robust_mgmt_frame(
1237 (struct ieee80211_hdr *) rx->skb->data)))
1238 return -EACCES;
1239 }
1240
1241 return 0;
1242 }
1243
1244 static int
1245 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1246 {
1247 struct net_device *dev = rx->dev;
1248 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1249
1250 return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type);
1251 }
1252
1253 /*
1254 * requires that rx->skb is a frame with ethernet header
1255 */
1256 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1257 {
1258 static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1259 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1260 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1261
1262 /*
1263 * Allow EAPOL frames to us/the PAE group address regardless
1264 * of whether the frame was encrypted or not.
1265 */
1266 if (ehdr->h_proto == htons(ETH_P_PAE) &&
1267 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1268 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1269 return true;
1270
1271 if (ieee80211_802_1x_port_control(rx) ||
1272 ieee80211_drop_unencrypted(rx, fc))
1273 return false;
1274
1275 return true;
1276 }
1277
1278 /*
1279 * requires that rx->skb is a frame with ethernet header
1280 */
1281 static void
1282 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1283 {
1284 struct net_device *dev = rx->dev;
1285 struct ieee80211_local *local = rx->local;
1286 struct sk_buff *skb, *xmit_skb;
1287 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1288 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1289 struct sta_info *dsta;
1290
1291 skb = rx->skb;
1292 xmit_skb = NULL;
1293
1294 if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1295 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1296 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1297 (rx->flags & IEEE80211_RX_RA_MATCH)) {
1298 if (is_multicast_ether_addr(ehdr->h_dest)) {
1299 /*
1300 * send multicast frames both to higher layers in
1301 * local net stack and back to the wireless medium
1302 */
1303 xmit_skb = skb_copy(skb, GFP_ATOMIC);
1304 if (!xmit_skb && net_ratelimit())
1305 printk(KERN_DEBUG "%s: failed to clone "
1306 "multicast frame\n", dev->name);
1307 } else {
1308 dsta = sta_info_get(local, skb->data);
1309 if (dsta && dsta->sdata->dev == dev) {
1310 /*
1311 * The destination station is associated to
1312 * this AP (in this VLAN), so send the frame
1313 * directly to it and do not pass it to local
1314 * net stack.
1315 */
1316 xmit_skb = skb;
1317 skb = NULL;
1318 }
1319 }
1320 }
1321
1322 if (skb) {
1323 int align __maybe_unused;
1324
1325 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1326 /*
1327 * 'align' will only take the values 0 or 2 here
1328 * since all frames are required to be aligned
1329 * to 2-byte boundaries when being passed to
1330 * mac80211. That also explains the __skb_push()
1331 * below.
1332 */
1333 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1334 if (align) {
1335 if (WARN_ON(skb_headroom(skb) < 3)) {
1336 dev_kfree_skb(skb);
1337 skb = NULL;
1338 } else {
1339 u8 *data = skb->data;
1340 size_t len = skb->len;
1341 u8 *new = __skb_push(skb, align);
1342 memmove(new, data, len);
1343 __skb_trim(skb, len);
1344 }
1345 }
1346 #endif
1347
1348 if (skb) {
1349 /* deliver to local stack */
1350 skb->protocol = eth_type_trans(skb, dev);
1351 memset(skb->cb, 0, sizeof(skb->cb));
1352 netif_rx(skb);
1353 }
1354 }
1355
1356 if (xmit_skb) {
1357 /* send to wireless media */
1358 xmit_skb->protocol = htons(ETH_P_802_3);
1359 skb_reset_network_header(xmit_skb);
1360 skb_reset_mac_header(xmit_skb);
1361 dev_queue_xmit(xmit_skb);
1362 }
1363 }
1364
1365 static ieee80211_rx_result debug_noinline
1366 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1367 {
1368 struct net_device *dev = rx->dev;
1369 struct ieee80211_local *local = rx->local;
1370 u16 ethertype;
1371 u8 *payload;
1372 struct sk_buff *skb = rx->skb, *frame = NULL;
1373 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1374 __le16 fc = hdr->frame_control;
1375 const struct ethhdr *eth;
1376 int remaining, err;
1377 u8 dst[ETH_ALEN];
1378 u8 src[ETH_ALEN];
1379
1380 if (unlikely(!ieee80211_is_data(fc)))
1381 return RX_CONTINUE;
1382
1383 if (unlikely(!ieee80211_is_data_present(fc)))
1384 return RX_DROP_MONITOR;
1385
1386 if (!(rx->flags & IEEE80211_RX_AMSDU))
1387 return RX_CONTINUE;
1388
1389 err = __ieee80211_data_to_8023(rx);
1390 if (unlikely(err))
1391 return RX_DROP_UNUSABLE;
1392
1393 skb->dev = dev;
1394
1395 dev->stats.rx_packets++;
1396 dev->stats.rx_bytes += skb->len;
1397
1398 /* skip the wrapping header */
1399 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1400 if (!eth)
1401 return RX_DROP_UNUSABLE;
1402
1403 while (skb != frame) {
1404 u8 padding;
1405 __be16 len = eth->h_proto;
1406 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1407
1408 remaining = skb->len;
1409 memcpy(dst, eth->h_dest, ETH_ALEN);
1410 memcpy(src, eth->h_source, ETH_ALEN);
1411
1412 padding = ((4 - subframe_len) & 0x3);
1413 /* the last MSDU has no padding */
1414 if (subframe_len > remaining)
1415 return RX_DROP_UNUSABLE;
1416
1417 skb_pull(skb, sizeof(struct ethhdr));
1418 /* if last subframe reuse skb */
1419 if (remaining <= subframe_len + padding)
1420 frame = skb;
1421 else {
1422 /*
1423 * Allocate and reserve two bytes more for payload
1424 * alignment since sizeof(struct ethhdr) is 14.
1425 */
1426 frame = dev_alloc_skb(
1427 ALIGN(local->hw.extra_tx_headroom, 4) +
1428 subframe_len + 2);
1429
1430 if (frame == NULL)
1431 return RX_DROP_UNUSABLE;
1432
1433 skb_reserve(frame,
1434 ALIGN(local->hw.extra_tx_headroom, 4) +
1435 sizeof(struct ethhdr) + 2);
1436 memcpy(skb_put(frame, ntohs(len)), skb->data,
1437 ntohs(len));
1438
1439 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1440 padding);
1441 if (!eth) {
1442 dev_kfree_skb(frame);
1443 return RX_DROP_UNUSABLE;
1444 }
1445 }
1446
1447 skb_reset_network_header(frame);
1448 frame->dev = dev;
1449 frame->priority = skb->priority;
1450 rx->skb = frame;
1451
1452 payload = frame->data;
1453 ethertype = (payload[6] << 8) | payload[7];
1454
1455 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1456 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1457 compare_ether_addr(payload,
1458 bridge_tunnel_header) == 0)) {
1459 /* remove RFC1042 or Bridge-Tunnel
1460 * encapsulation and replace EtherType */
1461 skb_pull(frame, 6);
1462 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1463 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1464 } else {
1465 memcpy(skb_push(frame, sizeof(__be16)),
1466 &len, sizeof(__be16));
1467 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1468 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1469 }
1470
1471 if (!ieee80211_frame_allowed(rx, fc)) {
1472 if (skb == frame) /* last frame */
1473 return RX_DROP_UNUSABLE;
1474 dev_kfree_skb(frame);
1475 continue;
1476 }
1477
1478 ieee80211_deliver_skb(rx);
1479 }
1480
1481 return RX_QUEUED;
1482 }
1483
1484 #ifdef CONFIG_MAC80211_MESH
1485 static ieee80211_rx_result
1486 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1487 {
1488 struct ieee80211_hdr *hdr;
1489 struct ieee80211s_hdr *mesh_hdr;
1490 unsigned int hdrlen;
1491 struct sk_buff *skb = rx->skb, *fwd_skb;
1492 struct ieee80211_local *local = rx->local;
1493 struct ieee80211_sub_if_data *sdata;
1494
1495 hdr = (struct ieee80211_hdr *) skb->data;
1496 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1497 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1498 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1499
1500 if (!ieee80211_is_data(hdr->frame_control))
1501 return RX_CONTINUE;
1502
1503 if (!mesh_hdr->ttl)
1504 /* illegal frame */
1505 return RX_DROP_MONITOR;
1506
1507 if (!is_multicast_ether_addr(hdr->addr1) &&
1508 (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6)) {
1509 struct mesh_path *mppath;
1510
1511 rcu_read_lock();
1512 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1513 if (!mppath) {
1514 mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1515 } else {
1516 spin_lock_bh(&mppath->state_lock);
1517 if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1518 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1519 spin_unlock_bh(&mppath->state_lock);
1520 }
1521 rcu_read_unlock();
1522 }
1523
1524 /* Frame has reached destination. Don't forward */
1525 if (!is_multicast_ether_addr(hdr->addr1) &&
1526 compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1527 return RX_CONTINUE;
1528
1529 mesh_hdr->ttl--;
1530
1531 if (rx->flags & IEEE80211_RX_RA_MATCH) {
1532 if (!mesh_hdr->ttl)
1533 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1534 dropped_frames_ttl);
1535 else {
1536 struct ieee80211_hdr *fwd_hdr;
1537 struct ieee80211_tx_info *info;
1538
1539 fwd_skb = skb_copy(skb, GFP_ATOMIC);
1540
1541 if (!fwd_skb && net_ratelimit())
1542 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1543 rx->dev->name);
1544
1545 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
1546 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1547 info = IEEE80211_SKB_CB(fwd_skb);
1548 memset(info, 0, sizeof(*info));
1549 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1550 info->control.vif = &rx->sdata->vif;
1551 skb_set_queue_mapping(skb,
1552 ieee80211_select_queue(rx->sdata, fwd_skb));
1553 ieee80211_set_qos_hdr(local, skb);
1554 if (is_multicast_ether_addr(fwd_hdr->addr1))
1555 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1556 fwded_mcast);
1557 else {
1558 int err;
1559 /*
1560 * Save TA to addr1 to send TA a path error if a
1561 * suitable next hop is not found
1562 */
1563 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1564 ETH_ALEN);
1565 err = mesh_nexthop_lookup(fwd_skb, sdata);
1566 /* Failed to immediately resolve next hop:
1567 * fwded frame was dropped or will be added
1568 * later to the pending skb queue. */
1569 if (err)
1570 return RX_DROP_MONITOR;
1571
1572 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1573 fwded_unicast);
1574 }
1575 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1576 fwded_frames);
1577 ieee80211_add_pending_skb(local, fwd_skb);
1578 }
1579 }
1580
1581 if (is_multicast_ether_addr(hdr->addr1) ||
1582 rx->dev->flags & IFF_PROMISC)
1583 return RX_CONTINUE;
1584 else
1585 return RX_DROP_MONITOR;
1586 }
1587 #endif
1588
1589 static ieee80211_rx_result debug_noinline
1590 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1591 {
1592 struct net_device *dev = rx->dev;
1593 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1594 __le16 fc = hdr->frame_control;
1595 int err;
1596
1597 if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1598 return RX_CONTINUE;
1599
1600 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1601 return RX_DROP_MONITOR;
1602
1603 err = __ieee80211_data_to_8023(rx);
1604 if (unlikely(err))
1605 return RX_DROP_UNUSABLE;
1606
1607 if (!ieee80211_frame_allowed(rx, fc))
1608 return RX_DROP_MONITOR;
1609
1610 rx->skb->dev = dev;
1611
1612 dev->stats.rx_packets++;
1613 dev->stats.rx_bytes += rx->skb->len;
1614
1615 ieee80211_deliver_skb(rx);
1616
1617 return RX_QUEUED;
1618 }
1619
1620 static ieee80211_rx_result debug_noinline
1621 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1622 {
1623 struct ieee80211_local *local = rx->local;
1624 struct ieee80211_hw *hw = &local->hw;
1625 struct sk_buff *skb = rx->skb;
1626 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1627 struct tid_ampdu_rx *tid_agg_rx;
1628 u16 start_seq_num;
1629 u16 tid;
1630
1631 if (likely(!ieee80211_is_ctl(bar->frame_control)))
1632 return RX_CONTINUE;
1633
1634 if (ieee80211_is_back_req(bar->frame_control)) {
1635 if (!rx->sta)
1636 return RX_CONTINUE;
1637 tid = le16_to_cpu(bar->control) >> 12;
1638 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1639 != HT_AGG_STATE_OPERATIONAL)
1640 return RX_CONTINUE;
1641 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1642
1643 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1644
1645 /* reset session timer */
1646 if (tid_agg_rx->timeout)
1647 mod_timer(&tid_agg_rx->session_timer,
1648 TU_TO_EXP_TIME(tid_agg_rx->timeout));
1649
1650 /* manage reordering buffer according to requested */
1651 /* sequence number */
1652 rcu_read_lock();
1653 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1654 start_seq_num, 1);
1655 rcu_read_unlock();
1656 return RX_DROP_UNUSABLE;
1657 }
1658
1659 return RX_CONTINUE;
1660 }
1661
1662 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1663 struct ieee80211_mgmt *mgmt,
1664 size_t len)
1665 {
1666 struct ieee80211_local *local = sdata->local;
1667 struct sk_buff *skb;
1668 struct ieee80211_mgmt *resp;
1669
1670 if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1671 /* Not to own unicast address */
1672 return;
1673 }
1674
1675 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1676 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1677 /* Not from the current AP or not associated yet. */
1678 return;
1679 }
1680
1681 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1682 /* Too short SA Query request frame */
1683 return;
1684 }
1685
1686 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1687 if (skb == NULL)
1688 return;
1689
1690 skb_reserve(skb, local->hw.extra_tx_headroom);
1691 resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1692 memset(resp, 0, 24);
1693 memcpy(resp->da, mgmt->sa, ETH_ALEN);
1694 memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1695 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1696 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1697 IEEE80211_STYPE_ACTION);
1698 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1699 resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1700 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1701 memcpy(resp->u.action.u.sa_query.trans_id,
1702 mgmt->u.action.u.sa_query.trans_id,
1703 WLAN_SA_QUERY_TR_ID_LEN);
1704
1705 ieee80211_tx_skb(sdata, skb, 1);
1706 }
1707
1708 static ieee80211_rx_result debug_noinline
1709 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1710 {
1711 struct ieee80211_local *local = rx->local;
1712 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1713 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1714 int len = rx->skb->len;
1715
1716 if (!ieee80211_is_action(mgmt->frame_control))
1717 return RX_CONTINUE;
1718
1719 if (!rx->sta)
1720 return RX_DROP_MONITOR;
1721
1722 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1723 return RX_DROP_MONITOR;
1724
1725 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1726 return RX_DROP_MONITOR;
1727
1728 /* all categories we currently handle have action_code */
1729 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1730 return RX_DROP_MONITOR;
1731
1732 switch (mgmt->u.action.category) {
1733 case WLAN_CATEGORY_BACK:
1734 /*
1735 * The aggregation code is not prepared to handle
1736 * anything but STA/AP due to the BSSID handling;
1737 * IBSS could work in the code but isn't supported
1738 * by drivers or the standard.
1739 */
1740 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1741 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1742 sdata->vif.type != NL80211_IFTYPE_AP)
1743 return RX_DROP_MONITOR;
1744
1745 switch (mgmt->u.action.u.addba_req.action_code) {
1746 case WLAN_ACTION_ADDBA_REQ:
1747 if (len < (IEEE80211_MIN_ACTION_SIZE +
1748 sizeof(mgmt->u.action.u.addba_req)))
1749 return RX_DROP_MONITOR;
1750 ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1751 break;
1752 case WLAN_ACTION_ADDBA_RESP:
1753 if (len < (IEEE80211_MIN_ACTION_SIZE +
1754 sizeof(mgmt->u.action.u.addba_resp)))
1755 return RX_DROP_MONITOR;
1756 ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1757 break;
1758 case WLAN_ACTION_DELBA:
1759 if (len < (IEEE80211_MIN_ACTION_SIZE +
1760 sizeof(mgmt->u.action.u.delba)))
1761 return RX_DROP_MONITOR;
1762 ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1763 break;
1764 }
1765 break;
1766 case WLAN_CATEGORY_SPECTRUM_MGMT:
1767 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1768 return RX_DROP_MONITOR;
1769
1770 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1771 return RX_DROP_MONITOR;
1772
1773 switch (mgmt->u.action.u.measurement.action_code) {
1774 case WLAN_ACTION_SPCT_MSR_REQ:
1775 if (len < (IEEE80211_MIN_ACTION_SIZE +
1776 sizeof(mgmt->u.action.u.measurement)))
1777 return RX_DROP_MONITOR;
1778 ieee80211_process_measurement_req(sdata, mgmt, len);
1779 break;
1780 case WLAN_ACTION_SPCT_CHL_SWITCH:
1781 if (len < (IEEE80211_MIN_ACTION_SIZE +
1782 sizeof(mgmt->u.action.u.chan_switch)))
1783 return RX_DROP_MONITOR;
1784
1785 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1786 return RX_DROP_MONITOR;
1787
1788 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1789 return RX_DROP_MONITOR;
1790
1791 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1792 }
1793 break;
1794 case WLAN_CATEGORY_SA_QUERY:
1795 if (len < (IEEE80211_MIN_ACTION_SIZE +
1796 sizeof(mgmt->u.action.u.sa_query)))
1797 return RX_DROP_MONITOR;
1798 switch (mgmt->u.action.u.sa_query.action) {
1799 case WLAN_ACTION_SA_QUERY_REQUEST:
1800 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1801 return RX_DROP_MONITOR;
1802 ieee80211_process_sa_query_req(sdata, mgmt, len);
1803 break;
1804 case WLAN_ACTION_SA_QUERY_RESPONSE:
1805 /*
1806 * SA Query response is currently only used in AP mode
1807 * and it is processed in user space.
1808 */
1809 return RX_CONTINUE;
1810 }
1811 break;
1812 default:
1813 /* do not process rejected action frames */
1814 if (mgmt->u.action.category & 0x80)
1815 return RX_DROP_MONITOR;
1816
1817 return RX_CONTINUE;
1818 }
1819
1820 rx->sta->rx_packets++;
1821 dev_kfree_skb(rx->skb);
1822 return RX_QUEUED;
1823 }
1824
1825 static ieee80211_rx_result debug_noinline
1826 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1827 {
1828 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1829 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1830
1831 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1832 return RX_DROP_MONITOR;
1833
1834 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1835 return RX_DROP_MONITOR;
1836
1837 if (ieee80211_vif_is_mesh(&sdata->vif))
1838 return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
1839
1840 if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1841 return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
1842
1843 if (sdata->vif.type == NL80211_IFTYPE_STATION)
1844 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1845
1846 return RX_DROP_MONITOR;
1847 }
1848
1849 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
1850 struct ieee80211_rx_data *rx)
1851 {
1852 int keyidx;
1853 unsigned int hdrlen;
1854
1855 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1856 if (rx->skb->len >= hdrlen + 4)
1857 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1858 else
1859 keyidx = -1;
1860
1861 if (!rx->sta) {
1862 /*
1863 * Some hardware seem to generate incorrect Michael MIC
1864 * reports; ignore them to avoid triggering countermeasures.
1865 */
1866 goto ignore;
1867 }
1868
1869 if (!ieee80211_has_protected(hdr->frame_control))
1870 goto ignore;
1871
1872 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1873 /*
1874 * APs with pairwise keys should never receive Michael MIC
1875 * errors for non-zero keyidx because these are reserved for
1876 * group keys and only the AP is sending real multicast
1877 * frames in the BSS.
1878 */
1879 goto ignore;
1880 }
1881
1882 if (!ieee80211_is_data(hdr->frame_control) &&
1883 !ieee80211_is_auth(hdr->frame_control))
1884 goto ignore;
1885
1886 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
1887 GFP_ATOMIC);
1888 ignore:
1889 dev_kfree_skb(rx->skb);
1890 rx->skb = NULL;
1891 }
1892
1893 /* TODO: use IEEE80211_RX_FRAGMENTED */
1894 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1895 {
1896 struct ieee80211_sub_if_data *sdata;
1897 struct ieee80211_local *local = rx->local;
1898 struct ieee80211_rtap_hdr {
1899 struct ieee80211_radiotap_header hdr;
1900 u8 flags;
1901 u8 rate;
1902 __le16 chan_freq;
1903 __le16 chan_flags;
1904 } __attribute__ ((packed)) *rthdr;
1905 struct sk_buff *skb = rx->skb, *skb2;
1906 struct net_device *prev_dev = NULL;
1907 struct ieee80211_rx_status *status = rx->status;
1908
1909 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1910 goto out_free_skb;
1911
1912 if (skb_headroom(skb) < sizeof(*rthdr) &&
1913 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1914 goto out_free_skb;
1915
1916 rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1917 memset(rthdr, 0, sizeof(*rthdr));
1918 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1919 rthdr->hdr.it_present =
1920 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1921 (1 << IEEE80211_RADIOTAP_RATE) |
1922 (1 << IEEE80211_RADIOTAP_CHANNEL));
1923
1924 rthdr->rate = rx->rate->bitrate / 5;
1925 rthdr->chan_freq = cpu_to_le16(status->freq);
1926
1927 if (status->band == IEEE80211_BAND_5GHZ)
1928 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1929 IEEE80211_CHAN_5GHZ);
1930 else
1931 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1932 IEEE80211_CHAN_2GHZ);
1933
1934 skb_set_mac_header(skb, 0);
1935 skb->ip_summed = CHECKSUM_UNNECESSARY;
1936 skb->pkt_type = PACKET_OTHERHOST;
1937 skb->protocol = htons(ETH_P_802_2);
1938
1939 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1940 if (!netif_running(sdata->dev))
1941 continue;
1942
1943 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1944 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1945 continue;
1946
1947 if (prev_dev) {
1948 skb2 = skb_clone(skb, GFP_ATOMIC);
1949 if (skb2) {
1950 skb2->dev = prev_dev;
1951 netif_rx(skb2);
1952 }
1953 }
1954
1955 prev_dev = sdata->dev;
1956 sdata->dev->stats.rx_packets++;
1957 sdata->dev->stats.rx_bytes += skb->len;
1958 }
1959
1960 if (prev_dev) {
1961 skb->dev = prev_dev;
1962 netif_rx(skb);
1963 skb = NULL;
1964 } else
1965 goto out_free_skb;
1966
1967 rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1968 return;
1969
1970 out_free_skb:
1971 dev_kfree_skb(skb);
1972 }
1973
1974
1975 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1976 struct ieee80211_rx_data *rx,
1977 struct sk_buff *skb)
1978 {
1979 ieee80211_rx_result res = RX_DROP_MONITOR;
1980
1981 rx->skb = skb;
1982 rx->sdata = sdata;
1983 rx->dev = sdata->dev;
1984
1985 #define CALL_RXH(rxh) \
1986 do { \
1987 res = rxh(rx); \
1988 if (res != RX_CONTINUE) \
1989 goto rxh_done; \
1990 } while (0);
1991
1992 CALL_RXH(ieee80211_rx_h_passive_scan)
1993 CALL_RXH(ieee80211_rx_h_check)
1994 CALL_RXH(ieee80211_rx_h_decrypt)
1995 CALL_RXH(ieee80211_rx_h_check_more_data)
1996 CALL_RXH(ieee80211_rx_h_sta_process)
1997 CALL_RXH(ieee80211_rx_h_defragment)
1998 CALL_RXH(ieee80211_rx_h_ps_poll)
1999 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2000 /* must be after MMIC verify so header is counted in MPDU mic */
2001 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2002 CALL_RXH(ieee80211_rx_h_amsdu)
2003 #ifdef CONFIG_MAC80211_MESH
2004 if (ieee80211_vif_is_mesh(&sdata->vif))
2005 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2006 #endif
2007 CALL_RXH(ieee80211_rx_h_data)
2008 CALL_RXH(ieee80211_rx_h_ctrl)
2009 CALL_RXH(ieee80211_rx_h_action)
2010 CALL_RXH(ieee80211_rx_h_mgmt)
2011
2012 #undef CALL_RXH
2013
2014 rxh_done:
2015 switch (res) {
2016 case RX_DROP_MONITOR:
2017 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2018 if (rx->sta)
2019 rx->sta->rx_dropped++;
2020 /* fall through */
2021 case RX_CONTINUE:
2022 ieee80211_rx_cooked_monitor(rx);
2023 break;
2024 case RX_DROP_UNUSABLE:
2025 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2026 if (rx->sta)
2027 rx->sta->rx_dropped++;
2028 dev_kfree_skb(rx->skb);
2029 break;
2030 case RX_QUEUED:
2031 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2032 break;
2033 }
2034 }
2035
2036 /* main receive path */
2037
2038 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2039 struct ieee80211_rx_data *rx,
2040 struct ieee80211_hdr *hdr)
2041 {
2042 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2043 int multicast = is_multicast_ether_addr(hdr->addr1);
2044
2045 switch (sdata->vif.type) {
2046 case NL80211_IFTYPE_STATION:
2047 if (!bssid)
2048 return 0;
2049 if (!multicast &&
2050 compare_ether_addr(sdata->dev->dev_addr, hdr->addr1) != 0) {
2051 if (!(sdata->dev->flags & IFF_PROMISC))
2052 return 0;
2053 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2054 }
2055 break;
2056 case NL80211_IFTYPE_ADHOC:
2057 if (!bssid)
2058 return 0;
2059 if (ieee80211_is_beacon(hdr->frame_control)) {
2060 return 1;
2061 }
2062 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2063 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2064 return 0;
2065 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2066 } else if (!multicast &&
2067 compare_ether_addr(sdata->dev->dev_addr,
2068 hdr->addr1) != 0) {
2069 if (!(sdata->dev->flags & IFF_PROMISC))
2070 return 0;
2071 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2072 } else if (!rx->sta) {
2073 int rate_idx;
2074 if (rx->status->flag & RX_FLAG_HT)
2075 rate_idx = 0; /* TODO: HT rates */
2076 else
2077 rate_idx = rx->status->rate_idx;
2078 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2079 BIT(rate_idx));
2080 }
2081 break;
2082 case NL80211_IFTYPE_MESH_POINT:
2083 if (!multicast &&
2084 compare_ether_addr(sdata->dev->dev_addr,
2085 hdr->addr1) != 0) {
2086 if (!(sdata->dev->flags & IFF_PROMISC))
2087 return 0;
2088
2089 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2090 }
2091 break;
2092 case NL80211_IFTYPE_AP_VLAN:
2093 case NL80211_IFTYPE_AP:
2094 if (!bssid) {
2095 if (compare_ether_addr(sdata->dev->dev_addr,
2096 hdr->addr1))
2097 return 0;
2098 } else if (!ieee80211_bssid_match(bssid,
2099 sdata->dev->dev_addr)) {
2100 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2101 return 0;
2102 rx->flags &= ~IEEE80211_RX_RA_MATCH;
2103 }
2104 break;
2105 case NL80211_IFTYPE_WDS:
2106 if (bssid || !ieee80211_is_data(hdr->frame_control))
2107 return 0;
2108 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2109 return 0;
2110 break;
2111 case NL80211_IFTYPE_MONITOR:
2112 /* take everything */
2113 break;
2114 case NL80211_IFTYPE_UNSPECIFIED:
2115 case __NL80211_IFTYPE_AFTER_LAST:
2116 /* should never get here */
2117 WARN_ON(1);
2118 break;
2119 }
2120
2121 return 1;
2122 }
2123
2124 /*
2125 * This is the actual Rx frames handler. as it blongs to Rx path it must
2126 * be called with rcu_read_lock protection.
2127 */
2128 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2129 struct sk_buff *skb,
2130 struct ieee80211_rate *rate)
2131 {
2132 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2133 struct ieee80211_local *local = hw_to_local(hw);
2134 struct ieee80211_sub_if_data *sdata;
2135 struct ieee80211_hdr *hdr;
2136 struct ieee80211_rx_data rx;
2137 int prepares;
2138 struct ieee80211_sub_if_data *prev = NULL;
2139 struct sk_buff *skb_new;
2140
2141 hdr = (struct ieee80211_hdr *)skb->data;
2142 memset(&rx, 0, sizeof(rx));
2143 rx.skb = skb;
2144 rx.local = local;
2145
2146 rx.status = status;
2147 rx.rate = rate;
2148
2149 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2150 local->dot11ReceivedFragmentCount++;
2151
2152 rx.sta = sta_info_get(local, hdr->addr2);
2153 if (rx.sta) {
2154 rx.sdata = rx.sta->sdata;
2155 rx.dev = rx.sta->sdata->dev;
2156 }
2157
2158 if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2159 ieee80211_rx_michael_mic_report(hdr, &rx);
2160 return;
2161 }
2162
2163 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2164 test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2165 rx.flags |= IEEE80211_RX_IN_SCAN;
2166
2167 ieee80211_parse_qos(&rx);
2168 ieee80211_verify_alignment(&rx);
2169
2170 skb = rx.skb;
2171
2172 if (rx.sdata && ieee80211_is_data(hdr->frame_control)) {
2173 rx.flags |= IEEE80211_RX_RA_MATCH;
2174 prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2175 if (prepares)
2176 prev = rx.sdata;
2177 } else list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2178 if (!netif_running(sdata->dev))
2179 continue;
2180
2181 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2182 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2183 continue;
2184
2185 rx.flags |= IEEE80211_RX_RA_MATCH;
2186 prepares = prepare_for_handlers(sdata, &rx, hdr);
2187
2188 if (!prepares)
2189 continue;
2190
2191 /*
2192 * frame is destined for this interface, but if it's not
2193 * also for the previous one we handle that after the
2194 * loop to avoid copying the SKB once too much
2195 */
2196
2197 if (!prev) {
2198 prev = sdata;
2199 continue;
2200 }
2201
2202 /*
2203 * frame was destined for the previous interface
2204 * so invoke RX handlers for it
2205 */
2206
2207 skb_new = skb_copy(skb, GFP_ATOMIC);
2208 if (!skb_new) {
2209 if (net_ratelimit())
2210 printk(KERN_DEBUG "%s: failed to copy "
2211 "multicast frame for %s\n",
2212 wiphy_name(local->hw.wiphy),
2213 prev->dev->name);
2214 continue;
2215 }
2216 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2217 prev = sdata;
2218 }
2219 if (prev)
2220 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2221 else
2222 dev_kfree_skb(skb);
2223 }
2224
2225 #define SEQ_MODULO 0x1000
2226 #define SEQ_MASK 0xfff
2227
2228 static inline int seq_less(u16 sq1, u16 sq2)
2229 {
2230 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2231 }
2232
2233 static inline u16 seq_inc(u16 sq)
2234 {
2235 return (sq + 1) & SEQ_MASK;
2236 }
2237
2238 static inline u16 seq_sub(u16 sq1, u16 sq2)
2239 {
2240 return (sq1 - sq2) & SEQ_MASK;
2241 }
2242
2243
2244 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
2245 struct tid_ampdu_rx *tid_agg_rx,
2246 int index)
2247 {
2248 struct ieee80211_supported_band *sband;
2249 struct ieee80211_rate *rate;
2250 struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
2251 struct ieee80211_rx_status *status;
2252
2253 if (!skb)
2254 goto no_frame;
2255
2256 status = IEEE80211_SKB_RXCB(skb);
2257
2258 /* release the reordered frames to stack */
2259 sband = hw->wiphy->bands[status->band];
2260 if (status->flag & RX_FLAG_HT)
2261 rate = sband->bitrates; /* TODO: HT rates */
2262 else
2263 rate = &sband->bitrates[status->rate_idx];
2264 __ieee80211_rx_handle_packet(hw, skb, rate);
2265 tid_agg_rx->stored_mpdu_num--;
2266 tid_agg_rx->reorder_buf[index] = NULL;
2267
2268 no_frame:
2269 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2270 }
2271
2272
2273 /*
2274 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
2275 * the skb was added to the buffer longer than this time ago, the earlier
2276 * frames that have not yet been received are assumed to be lost and the skb
2277 * can be released for processing. This may also release other skb's from the
2278 * reorder buffer if there are no additional gaps between the frames.
2279 */
2280 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
2281
2282 /*
2283 * As it function blongs to Rx path it must be called with
2284 * the proper rcu_read_lock protection for its flow.
2285 */
2286 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2287 struct tid_ampdu_rx *tid_agg_rx,
2288 struct sk_buff *skb,
2289 u16 mpdu_seq_num,
2290 int bar_req)
2291 {
2292 u16 head_seq_num, buf_size;
2293 int index;
2294
2295 buf_size = tid_agg_rx->buf_size;
2296 head_seq_num = tid_agg_rx->head_seq_num;
2297
2298 /* frame with out of date sequence number */
2299 if (seq_less(mpdu_seq_num, head_seq_num)) {
2300 dev_kfree_skb(skb);
2301 return 1;
2302 }
2303
2304 /* if frame sequence number exceeds our buffering window size or
2305 * block Ack Request arrived - release stored frames */
2306 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2307 /* new head to the ordering buffer */
2308 if (bar_req)
2309 head_seq_num = mpdu_seq_num;
2310 else
2311 head_seq_num =
2312 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2313 /* release stored frames up to new head to stack */
2314 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2315 index = seq_sub(tid_agg_rx->head_seq_num,
2316 tid_agg_rx->ssn)
2317 % tid_agg_rx->buf_size;
2318 ieee80211_release_reorder_frame(hw, tid_agg_rx,
2319 index);
2320 }
2321 if (bar_req)
2322 return 1;
2323 }
2324
2325 /* now the new frame is always in the range of the reordering */
2326 /* buffer window */
2327 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2328 % tid_agg_rx->buf_size;
2329 /* check if we already stored this frame */
2330 if (tid_agg_rx->reorder_buf[index]) {
2331 dev_kfree_skb(skb);
2332 return 1;
2333 }
2334
2335 /* if arrived mpdu is in the right order and nothing else stored */
2336 /* release it immediately */
2337 if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2338 tid_agg_rx->stored_mpdu_num == 0) {
2339 tid_agg_rx->head_seq_num =
2340 seq_inc(tid_agg_rx->head_seq_num);
2341 return 0;
2342 }
2343
2344 /* put the frame in the reordering buffer */
2345 tid_agg_rx->reorder_buf[index] = skb;
2346 tid_agg_rx->reorder_time[index] = jiffies;
2347 tid_agg_rx->stored_mpdu_num++;
2348 /* release the buffer until next missing frame */
2349 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2350 % tid_agg_rx->buf_size;
2351 if (!tid_agg_rx->reorder_buf[index] &&
2352 tid_agg_rx->stored_mpdu_num > 1) {
2353 /*
2354 * No buffers ready to be released, but check whether any
2355 * frames in the reorder buffer have timed out.
2356 */
2357 int j;
2358 int skipped = 1;
2359 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
2360 j = (j + 1) % tid_agg_rx->buf_size) {
2361 if (tid_agg_rx->reorder_buf[j] == NULL) {
2362 skipped++;
2363 continue;
2364 }
2365 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
2366 HZ / 10))
2367 break;
2368
2369 #ifdef CONFIG_MAC80211_HT_DEBUG
2370 if (net_ratelimit())
2371 printk(KERN_DEBUG "%s: release an RX reorder "
2372 "frame due to timeout on earlier "
2373 "frames\n",
2374 wiphy_name(hw->wiphy));
2375 #endif
2376 ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
2377
2378 /*
2379 * Increment the head seq# also for the skipped slots.
2380 */
2381 tid_agg_rx->head_seq_num =
2382 (tid_agg_rx->head_seq_num + skipped) &
2383 SEQ_MASK;
2384 skipped = 0;
2385 }
2386 } else while (tid_agg_rx->reorder_buf[index]) {
2387 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
2388 index = seq_sub(tid_agg_rx->head_seq_num,
2389 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2390 }
2391 return 1;
2392 }
2393
2394 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2395 struct sk_buff *skb)
2396 {
2397 struct ieee80211_hw *hw = &local->hw;
2398 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2399 struct sta_info *sta;
2400 struct tid_ampdu_rx *tid_agg_rx;
2401 u16 sc;
2402 u16 mpdu_seq_num;
2403 u8 ret = 0;
2404 int tid;
2405
2406 sta = sta_info_get(local, hdr->addr2);
2407 if (!sta)
2408 return ret;
2409
2410 /* filter the QoS data rx stream according to
2411 * STA/TID and check if this STA/TID is on aggregation */
2412 if (!ieee80211_is_data_qos(hdr->frame_control))
2413 goto end_reorder;
2414
2415 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2416
2417 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2418 goto end_reorder;
2419
2420 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2421
2422 /* qos null data frames are excluded */
2423 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2424 goto end_reorder;
2425
2426 /* new un-ordered ampdu frame - process it */
2427
2428 /* reset session timer */
2429 if (tid_agg_rx->timeout)
2430 mod_timer(&tid_agg_rx->session_timer,
2431 TU_TO_EXP_TIME(tid_agg_rx->timeout));
2432
2433 /* if this mpdu is fragmented - terminate rx aggregation session */
2434 sc = le16_to_cpu(hdr->seq_ctrl);
2435 if (sc & IEEE80211_SCTL_FRAG) {
2436 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2437 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2438 ret = 1;
2439 goto end_reorder;
2440 }
2441
2442 /* according to mpdu sequence number deal with reordering buffer */
2443 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2444 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2445 mpdu_seq_num, 0);
2446 end_reorder:
2447 return ret;
2448 }
2449
2450 /*
2451 * This is the receive path handler. It is called by a low level driver when an
2452 * 802.11 MPDU is received from the hardware.
2453 */
2454 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2455 {
2456 struct ieee80211_local *local = hw_to_local(hw);
2457 struct ieee80211_rate *rate = NULL;
2458 struct ieee80211_supported_band *sband;
2459 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2460
2461 WARN_ON_ONCE(softirq_count() == 0);
2462
2463 if (WARN_ON(status->band < 0 ||
2464 status->band >= IEEE80211_NUM_BANDS))
2465 goto drop;
2466
2467 sband = local->hw.wiphy->bands[status->band];
2468 if (WARN_ON(!sband))
2469 goto drop;
2470
2471 /*
2472 * If we're suspending, it is possible although not too likely
2473 * that we'd be receiving frames after having already partially
2474 * quiesced the stack. We can't process such frames then since
2475 * that might, for example, cause stations to be added or other
2476 * driver callbacks be invoked.
2477 */
2478 if (unlikely(local->quiescing || local->suspended))
2479 goto drop;
2480
2481 /*
2482 * The same happens when we're not even started,
2483 * but that's worth a warning.
2484 */
2485 if (WARN_ON(!local->started))
2486 goto drop;
2487
2488 if (status->flag & RX_FLAG_HT) {
2489 /* rate_idx is MCS index */
2490 if (WARN_ON(status->rate_idx < 0 ||
2491 status->rate_idx >= 76))
2492 goto drop;
2493 /* HT rates are not in the table - use the highest legacy rate
2494 * for now since other parts of mac80211 may not yet be fully
2495 * MCS aware. */
2496 rate = &sband->bitrates[sband->n_bitrates - 1];
2497 } else {
2498 if (WARN_ON(status->rate_idx < 0 ||
2499 status->rate_idx >= sband->n_bitrates))
2500 goto drop;
2501 rate = &sband->bitrates[status->rate_idx];
2502 }
2503
2504 /*
2505 * key references and virtual interfaces are protected using RCU
2506 * and this requires that we are in a read-side RCU section during
2507 * receive processing
2508 */
2509 rcu_read_lock();
2510
2511 /*
2512 * Frames with failed FCS/PLCP checksum are not returned,
2513 * all other frames are returned without radiotap header
2514 * if it was previously present.
2515 * Also, frames with less than 16 bytes are dropped.
2516 */
2517 skb = ieee80211_rx_monitor(local, skb, rate);
2518 if (!skb) {
2519 rcu_read_unlock();
2520 return;
2521 }
2522
2523 /*
2524 * In theory, the block ack reordering should happen after duplicate
2525 * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
2526 * the call to ieee80211_rx_reorder_ampdu() should really be moved to
2527 * happen as a new RX handler between ieee80211_rx_h_check and
2528 * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
2529 * the time being, the call can be here since RX reorder buf processing
2530 * will implicitly skip duplicates. We could, in theory at least,
2531 * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
2532 * frames from other than operational channel), but that should not
2533 * happen in normal networks.
2534 */
2535 if (!ieee80211_rx_reorder_ampdu(local, skb))
2536 __ieee80211_rx_handle_packet(hw, skb, rate);
2537
2538 rcu_read_unlock();
2539
2540 return;
2541 drop:
2542 kfree_skb(skb);
2543 }
2544 EXPORT_SYMBOL(ieee80211_rx);
2545
2546 /* This is a version of the rx handler that can be called from hard irq
2547 * context. Post the skb on the queue and schedule the tasklet */
2548 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2549 {
2550 struct ieee80211_local *local = hw_to_local(hw);
2551
2552 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2553
2554 skb->pkt_type = IEEE80211_RX_MSG;
2555 skb_queue_tail(&local->skb_queue, skb);
2556 tasklet_schedule(&local->tasklet);
2557 }
2558 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
kernels