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 "led.h"
23 #include "mesh.h"
24 #include "wep.h"
25 #include "wpa.h"
26 #include "tkip.h"
27 #include "wme.h"
28
29 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
30 struct tid_ampdu_rx *tid_agg_rx,
31 struct sk_buff *skb,
32 u16 mpdu_seq_num,
33 int bar_req);
34 /*
35 * monitor mode reception
36 *
37 * This function cleans up the SKB, i.e. it removes all the stuff
38 * only useful for monitoring.
39 */
remove_monitor_info(struct ieee80211_local * local,struct sk_buff * skb,int rtap_len)40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
41 struct sk_buff *skb,
42 int rtap_len)
43 {
44 skb_pull(skb, rtap_len);
45
46 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
47 if (likely(skb->len > FCS_LEN))
48 skb_trim(skb, skb->len - FCS_LEN);
49 else {
50 /* driver bug */
51 WARN_ON(1);
52 dev_kfree_skb(skb);
53 skb = NULL;
54 }
55 }
56
57 return skb;
58 }
59
should_drop_frame(struct ieee80211_rx_status * status,struct sk_buff * skb,int present_fcs_len,int radiotap_len)60 static inline int should_drop_frame(struct ieee80211_rx_status *status,
61 struct sk_buff *skb,
62 int present_fcs_len,
63 int radiotap_len)
64 {
65 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
66
67 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
68 return 1;
69 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
70 return 1;
71 if (ieee80211_is_ctl(hdr->frame_control) &&
72 !ieee80211_is_pspoll(hdr->frame_control) &&
73 !ieee80211_is_back_req(hdr->frame_control))
74 return 1;
75 return 0;
76 }
77
78 static int
ieee80211_rx_radiotap_len(struct ieee80211_local * local,struct ieee80211_rx_status * status)79 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
80 struct ieee80211_rx_status *status)
81 {
82 int len;
83
84 /* always present fields */
85 len = sizeof(struct ieee80211_radiotap_header) + 9;
86
87 if (status->flag & RX_FLAG_TSFT)
88 len += 8;
89 if (local->hw.flags & IEEE80211_HW_SIGNAL_DB ||
90 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
ieee80211_add_rx_radiotap_header(struct ieee80211_local * local,struct sk_buff * skb,struct ieee80211_rx_status * status,struct ieee80211_rate * rate,int rtap_len)111 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
112 struct sk_buff *skb,
113 struct ieee80211_rx_status *status,
114 struct ieee80211_rate *rate,
115 int rtap_len)
116 {
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_SHORTPRE)
147 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
148 pos++;
149
150 /* IEEE80211_RADIOTAP_RATE */
151 if (status->flag & RX_FLAG_HT) {
152 /*
153 * TODO: add following information into radiotap header once
154 * suitable fields are defined for it:
155 * - MCS index (status->rate_idx)
156 * - HT40 (status->flag & RX_FLAG_40MHZ)
157 * - short-GI (status->flag & RX_FLAG_SHORT_GI)
158 */
159 *pos = 0;
160 } else {
161 rthdr->it_present |= (1 << IEEE80211_RADIOTAP_RATE);
162 *pos = rate->bitrate / 5;
163 }
164 pos++;
165
166 /* IEEE80211_RADIOTAP_CHANNEL */
167 *(__le16 *)pos = cpu_to_le16(status->freq);
168 pos += 2;
169 if (status->band == IEEE80211_BAND_5GHZ)
170 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
171 IEEE80211_CHAN_5GHZ);
172 else if (rate->flags & IEEE80211_RATE_ERP_G)
173 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
174 IEEE80211_CHAN_2GHZ);
175 else
176 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
177 IEEE80211_CHAN_2GHZ);
178 pos += 2;
179
180 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
181 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
182 *pos = status->signal;
183 rthdr->it_present |=
184 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
185 pos++;
186 }
187
188 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
189 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
190 *pos = status->noise;
191 rthdr->it_present |=
192 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
193 pos++;
194 }
195
196 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
197
198 /* IEEE80211_RADIOTAP_ANTENNA */
199 *pos = status->antenna;
200 pos++;
201
202 /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
203 if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
204 *pos = status->signal;
205 rthdr->it_present |=
206 cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
207 pos++;
208 }
209
210 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
211
212 /* IEEE80211_RADIOTAP_RX_FLAGS */
213 /* ensure 2 byte alignment for the 2 byte field as required */
214 if ((pos - (unsigned char *)rthdr) & 1)
215 pos++;
216 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
217 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
218 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
219 pos += 2;
220 }
221
222 /*
223 * This function copies a received frame to all monitor interfaces and
224 * returns a cleaned-up SKB that no longer includes the FCS nor the
225 * radiotap header the driver might have added.
226 */
227 static struct sk_buff *
ieee80211_rx_monitor(struct ieee80211_local * local,struct sk_buff * origskb,struct ieee80211_rx_status * status,struct ieee80211_rate * rate)228 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
229 struct ieee80211_rx_status *status,
230 struct ieee80211_rate *rate)
231 {
232 struct ieee80211_sub_if_data *sdata;
233 int needed_headroom = 0;
234 struct sk_buff *skb, *skb2;
235 struct net_device *prev_dev = NULL;
236 int present_fcs_len = 0;
237 int rtap_len = 0;
238
239 /*
240 * First, we may need to make a copy of the skb because
241 * (1) we need to modify it for radiotap (if not present), and
242 * (2) the other RX handlers will modify the skb we got.
243 *
244 * We don't need to, of course, if we aren't going to return
245 * the SKB because it has a bad FCS/PLCP checksum.
246 */
247 if (status->flag & RX_FLAG_RADIOTAP)
248 rtap_len = ieee80211_get_radiotap_len(origskb->data);
249 else
250 /* room for the radiotap header based on driver features */
251 needed_headroom = ieee80211_rx_radiotap_len(local, status);
252
253 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
254 present_fcs_len = FCS_LEN;
255
256 if (!local->monitors) {
257 if (should_drop_frame(status, origskb, present_fcs_len,
258 rtap_len)) {
259 dev_kfree_skb(origskb);
260 return NULL;
261 }
262
263 return remove_monitor_info(local, origskb, rtap_len);
264 }
265
266 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
267 /* only need to expand headroom if necessary */
268 skb = origskb;
269 origskb = NULL;
270
271 /*
272 * This shouldn't trigger often because most devices have an
273 * RX header they pull before we get here, and that should
274 * be big enough for our radiotap information. We should
275 * probably export the length to drivers so that we can have
276 * them allocate enough headroom to start with.
277 */
278 if (skb_headroom(skb) < needed_headroom &&
279 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
280 dev_kfree_skb(skb);
281 return NULL;
282 }
283 } else {
284 /*
285 * Need to make a copy and possibly remove radiotap header
286 * and FCS from the original.
287 */
288 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
289
290 origskb = remove_monitor_info(local, origskb, rtap_len);
291
292 if (!skb)
293 return origskb;
294 }
295
296 /* if necessary, prepend radiotap information */
297 if (!(status->flag & RX_FLAG_RADIOTAP))
298 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
299 needed_headroom);
300
301 skb_reset_mac_header(skb);
302 skb->ip_summed = CHECKSUM_UNNECESSARY;
303 skb->pkt_type = PACKET_OTHERHOST;
304 skb->protocol = htons(ETH_P_802_2);
305
306 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
307 if (!netif_running(sdata->dev))
308 continue;
309
310 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
311 continue;
312
313 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
314 continue;
315
316 if (prev_dev) {
317 skb2 = skb_clone(skb, GFP_ATOMIC);
318 if (skb2) {
319 skb2->dev = prev_dev;
320 netif_rx(skb2);
321 }
322 }
323
324 prev_dev = sdata->dev;
325 sdata->dev->stats.rx_packets++;
326 sdata->dev->stats.rx_bytes += skb->len;
327 }
328
329 if (prev_dev) {
330 skb->dev = prev_dev;
331 netif_rx(skb);
332 } else
333 dev_kfree_skb(skb);
334
335 return origskb;
336 }
337
338
ieee80211_parse_qos(struct ieee80211_rx_data * rx)339 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
340 {
341 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
342 int tid;
343
344 /* does the frame have a qos control field? */
345 if (ieee80211_is_data_qos(hdr->frame_control)) {
346 u8 *qc = ieee80211_get_qos_ctl(hdr);
347 /* frame has qos control */
348 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
349 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
350 rx->flags |= IEEE80211_RX_AMSDU;
351 else
352 rx->flags &= ~IEEE80211_RX_AMSDU;
353 } else {
354 /*
355 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
356 *
357 * Sequence numbers for management frames, QoS data
358 * frames with a broadcast/multicast address in the
359 * Address 1 field, and all non-QoS data frames sent
360 * by QoS STAs are assigned using an additional single
361 * modulo-4096 counter, [...]
362 *
363 * We also use that counter for non-QoS STAs.
364 */
365 tid = NUM_RX_DATA_QUEUES - 1;
366 }
367
368 rx->queue = tid;
369 /* Set skb->priority to 1d tag if highest order bit of TID is not set.
370 * For now, set skb->priority to 0 for other cases. */
371 rx->skb->priority = (tid > 7) ? 0 : tid;
372 }
373
ieee80211_verify_ip_alignment(struct ieee80211_rx_data * rx)374 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
375 {
376 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
377 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
378 int hdrlen;
379
380 if (!ieee80211_is_data_present(hdr->frame_control))
381 return;
382
383 /*
384 * Drivers are required to align the payload data in a way that
385 * guarantees that the contained IP header is aligned to a four-
386 * byte boundary. In the case of regular frames, this simply means
387 * aligning the payload to a four-byte boundary (because either
388 * the IP header is directly contained, or IV/RFC1042 headers that
389 * have a length divisible by four are in front of it.
390 *
391 * With A-MSDU frames, however, the payload data address must
392 * yield two modulo four because there are 14-byte 802.3 headers
393 * within the A-MSDU frames that push the IP header further back
394 * to a multiple of four again. Thankfully, the specs were sane
395 * enough this time around to require padding each A-MSDU subframe
396 * to a length that is a multiple of four.
397 *
398 * Padding like atheros hardware adds which is inbetween the 802.11
399 * header and the payload is not supported, the driver is required
400 * to move the 802.11 header further back in that case.
401 */
402 hdrlen = ieee80211_hdrlen(hdr->frame_control);
403 if (rx->flags & IEEE80211_RX_AMSDU)
404 hdrlen += ETH_HLEN;
405 WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
406 #endif
407 }
408
409
410 /* rx handlers */
411
412 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_passive_scan(struct ieee80211_rx_data * rx)413 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
414 {
415 struct ieee80211_local *local = rx->local;
416 struct sk_buff *skb = rx->skb;
417
418 if (unlikely(local->hw_scanning))
419 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
420
421 if (unlikely(local->sw_scanning)) {
422 /* drop all the other packets during a software scan anyway */
423 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
424 != RX_QUEUED)
425 dev_kfree_skb(skb);
426 return RX_QUEUED;
427 }
428
429 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
430 /* scanning finished during invoking of handlers */
431 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
432 return RX_DROP_UNUSABLE;
433 }
434
435 return RX_CONTINUE;
436 }
437
438 static ieee80211_rx_result
ieee80211_rx_mesh_check(struct ieee80211_rx_data * rx)439 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
440 {
441 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
442 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
443
444 if (ieee80211_is_data(hdr->frame_control)) {
445 if (!ieee80211_has_a4(hdr->frame_control))
446 return RX_DROP_MONITOR;
447 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
448 return RX_DROP_MONITOR;
449 }
450
451 /* If there is not an established peer link and this is not a peer link
452 * establisment frame, beacon or probe, drop the frame.
453 */
454
455 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
456 struct ieee80211_mgmt *mgmt;
457
458 if (!ieee80211_is_mgmt(hdr->frame_control))
459 return RX_DROP_MONITOR;
460
461 if (ieee80211_is_action(hdr->frame_control)) {
462 mgmt = (struct ieee80211_mgmt *)hdr;
463 if (mgmt->u.action.category != PLINK_CATEGORY)
464 return RX_DROP_MONITOR;
465 return RX_CONTINUE;
466 }
467
468 if (ieee80211_is_probe_req(hdr->frame_control) ||
469 ieee80211_is_probe_resp(hdr->frame_control) ||
470 ieee80211_is_beacon(hdr->frame_control))
471 return RX_CONTINUE;
472
473 return RX_DROP_MONITOR;
474
475 }
476
477 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
478
479 if (ieee80211_is_data(hdr->frame_control) &&
480 is_multicast_ether_addr(hdr->addr1) &&
481 mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
482 return RX_DROP_MONITOR;
483 #undef msh_h_get
484
485 return RX_CONTINUE;
486 }
487
488
489 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_check(struct ieee80211_rx_data * rx)490 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
491 {
492 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
493
494 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
495 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
496 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
497 rx->sta->last_seq_ctrl[rx->queue] ==
498 hdr->seq_ctrl)) {
499 if (rx->flags & IEEE80211_RX_RA_MATCH) {
500 rx->local->dot11FrameDuplicateCount++;
501 rx->sta->num_duplicates++;
502 }
503 return RX_DROP_MONITOR;
504 } else
505 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
506 }
507
508 if (unlikely(rx->skb->len < 16)) {
509 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
510 return RX_DROP_MONITOR;
511 }
512
513 /* Drop disallowed frame classes based on STA auth/assoc state;
514 * IEEE 802.11, Chap 5.5.
515 *
516 * mac80211 filters only based on association state, i.e. it drops
517 * Class 3 frames from not associated stations. hostapd sends
518 * deauth/disassoc frames when needed. In addition, hostapd is
519 * responsible for filtering on both auth and assoc states.
520 */
521
522 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
523 return ieee80211_rx_mesh_check(rx);
524
525 if (unlikely((ieee80211_is_data(hdr->frame_control) ||
526 ieee80211_is_pspoll(hdr->frame_control)) &&
527 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
528 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
529 if ((!ieee80211_has_fromds(hdr->frame_control) &&
530 !ieee80211_has_tods(hdr->frame_control) &&
531 ieee80211_is_data(hdr->frame_control)) ||
532 !(rx->flags & IEEE80211_RX_RA_MATCH)) {
533 /* Drop IBSS frames and frames for other hosts
534 * silently. */
535 return RX_DROP_MONITOR;
536 }
537
538 return RX_DROP_MONITOR;
539 }
540
541 return RX_CONTINUE;
542 }
543
544
545 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_decrypt(struct ieee80211_rx_data * rx)546 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
547 {
548 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
549 int keyidx;
550 int hdrlen;
551 ieee80211_rx_result result = RX_DROP_UNUSABLE;
552 struct ieee80211_key *stakey = NULL;
553
554 /*
555 * Key selection 101
556 *
557 * There are three types of keys:
558 * - GTK (group keys)
559 * - PTK (pairwise keys)
560 * - STK (station-to-station pairwise keys)
561 *
562 * When selecting a key, we have to distinguish between multicast
563 * (including broadcast) and unicast frames, the latter can only
564 * use PTKs and STKs while the former always use GTKs. Unless, of
565 * course, actual WEP keys ("pre-RSNA") are used, then unicast
566 * frames can also use key indizes like GTKs. Hence, if we don't
567 * have a PTK/STK we check the key index for a WEP key.
568 *
569 * Note that in a regular BSS, multicast frames are sent by the
570 * AP only, associated stations unicast the frame to the AP first
571 * which then multicasts it on their behalf.
572 *
573 * There is also a slight problem in IBSS mode: GTKs are negotiated
574 * with each station, that is something we don't currently handle.
575 * The spec seems to expect that one negotiates the same key with
576 * every station but there's no such requirement; VLANs could be
577 * possible.
578 */
579
580 if (!ieee80211_has_protected(hdr->frame_control))
581 return RX_CONTINUE;
582
583 /*
584 * No point in finding a key and decrypting if the frame is neither
585 * addressed to us nor a multicast frame.
586 */
587 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
588 return RX_CONTINUE;
589
590 if (rx->sta)
591 stakey = rcu_dereference(rx->sta->key);
592
593 if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
594 rx->key = stakey;
595 } else {
596 /*
597 * The device doesn't give us the IV so we won't be
598 * able to look up the key. That's ok though, we
599 * don't need to decrypt the frame, we just won't
600 * be able to keep statistics accurate.
601 * Except for key threshold notifications, should
602 * we somehow allow the driver to tell us which key
603 * the hardware used if this flag is set?
604 */
605 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
606 (rx->status->flag & RX_FLAG_IV_STRIPPED))
607 return RX_CONTINUE;
608
609 hdrlen = ieee80211_hdrlen(hdr->frame_control);
610
611 if (rx->skb->len < 8 + hdrlen)
612 return RX_DROP_UNUSABLE; /* TODO: count this? */
613
614 /*
615 * no need to call ieee80211_wep_get_keyidx,
616 * it verifies a bunch of things we've done already
617 */
618 keyidx = rx->skb->data[hdrlen + 3] >> 6;
619
620 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
621
622 /*
623 * RSNA-protected unicast frames should always be sent with
624 * pairwise or station-to-station keys, but for WEP we allow
625 * using a key index as well.
626 */
627 if (rx->key && rx->key->conf.alg != ALG_WEP &&
628 !is_multicast_ether_addr(hdr->addr1))
629 rx->key = NULL;
630 }
631
632 if (rx->key) {
633 rx->key->tx_rx_count++;
634 /* TODO: add threshold stuff again */
635 } else {
636 return RX_DROP_MONITOR;
637 }
638
639 /* Check for weak IVs if possible */
640 if (rx->sta && rx->key->conf.alg == ALG_WEP &&
641 ieee80211_is_data(hdr->frame_control) &&
642 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
643 !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
644 ieee80211_wep_is_weak_iv(rx->skb, rx->key))
645 rx->sta->wep_weak_iv_count++;
646
647 switch (rx->key->conf.alg) {
648 case ALG_WEP:
649 result = ieee80211_crypto_wep_decrypt(rx);
650 break;
651 case ALG_TKIP:
652 result = ieee80211_crypto_tkip_decrypt(rx);
653 break;
654 case ALG_CCMP:
655 result = ieee80211_crypto_ccmp_decrypt(rx);
656 break;
657 }
658
659 /* either the frame has been decrypted or will be dropped */
660 rx->status->flag |= RX_FLAG_DECRYPTED;
661
662 return result;
663 }
664
ap_sta_ps_start(struct sta_info * sta)665 static void ap_sta_ps_start(struct sta_info *sta)
666 {
667 struct ieee80211_sub_if_data *sdata = sta->sdata;
668 struct ieee80211_local *local = sdata->local;
669
670 atomic_inc(&sdata->bss->num_sta_ps);
671 set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
672 if (local->ops->sta_notify)
673 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
674 STA_NOTIFY_SLEEP, &sta->sta);
675 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
676 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
677 sdata->dev->name, sta->sta.addr, sta->sta.aid);
678 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
679 }
680
ap_sta_ps_end(struct sta_info * sta)681 static int ap_sta_ps_end(struct sta_info *sta)
682 {
683 struct ieee80211_sub_if_data *sdata = sta->sdata;
684 struct ieee80211_local *local = sdata->local;
685 struct sk_buff *skb;
686 int sent = 0;
687
688 atomic_dec(&sdata->bss->num_sta_ps);
689
690 clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
691 if (local->ops->sta_notify)
692 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
693 STA_NOTIFY_AWAKE, &sta->sta);
694
695 if (!skb_queue_empty(&sta->ps_tx_buf))
696 sta_info_clear_tim_bit(sta);
697
698 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
699 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
700 sdata->dev->name, sta->sta.addr, sta->sta.aid);
701 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
702
703 /* Send all buffered frames to the station */
704 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
705 sent++;
706 skb->requeue = 1;
707 dev_queue_xmit(skb);
708 }
709 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
710 local->total_ps_buffered--;
711 sent++;
712 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
713 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
714 "since STA not sleeping anymore\n", sdata->dev->name,
715 sta->sta.addr, sta->sta.aid);
716 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
717 skb->requeue = 1;
718 dev_queue_xmit(skb);
719 }
720
721 return sent;
722 }
723
724 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_sta_process(struct ieee80211_rx_data * rx)725 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
726 {
727 struct sta_info *sta = rx->sta;
728 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
729
730 if (!sta)
731 return RX_CONTINUE;
732
733 /* Update last_rx only for IBSS packets which are for the current
734 * BSSID to avoid keeping the current IBSS network alive in cases where
735 * other STAs are using different BSSID. */
736 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
737 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
738 NL80211_IFTYPE_ADHOC);
739 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
740 sta->last_rx = jiffies;
741 } else
742 if (!is_multicast_ether_addr(hdr->addr1) ||
743 rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
744 /* Update last_rx only for unicast frames in order to prevent
745 * the Probe Request frames (the only broadcast frames from a
746 * STA in infrastructure mode) from keeping a connection alive.
747 * Mesh beacons will update last_rx when if they are found to
748 * match the current local configuration when processed.
749 */
750 sta->last_rx = jiffies;
751 }
752
753 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
754 return RX_CONTINUE;
755
756 sta->rx_fragments++;
757 sta->rx_bytes += rx->skb->len;
758 sta->last_signal = rx->status->signal;
759 sta->last_qual = rx->status->qual;
760 sta->last_noise = rx->status->noise;
761
762 /*
763 * Change STA power saving mode only at the end of a frame
764 * exchange sequence.
765 */
766 if (!ieee80211_has_morefrags(hdr->frame_control) &&
767 (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
768 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
769 if (test_sta_flags(sta, WLAN_STA_PS)) {
770 /*
771 * Ignore doze->wake transitions that are
772 * indicated by non-data frames, the standard
773 * is unclear here, but for example going to
774 * PS mode and then scanning would cause a
775 * doze->wake transition for the probe request,
776 * and that is clearly undesirable.
777 */
778 if (ieee80211_is_data(hdr->frame_control) &&
779 !ieee80211_has_pm(hdr->frame_control))
780 rx->sent_ps_buffered += ap_sta_ps_end(sta);
781 } else {
782 if (ieee80211_has_pm(hdr->frame_control))
783 ap_sta_ps_start(sta);
784 }
785 }
786
787 /* Drop data::nullfunc frames silently, since they are used only to
788 * control station power saving mode. */
789 if (ieee80211_is_nullfunc(hdr->frame_control)) {
790 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
791 /* Update counter and free packet here to avoid counting this
792 * as a dropped packed. */
793 sta->rx_packets++;
794 dev_kfree_skb(rx->skb);
795 return RX_QUEUED;
796 }
797
798 return RX_CONTINUE;
799 } /* ieee80211_rx_h_sta_process */
800
801 static inline struct ieee80211_fragment_entry *
ieee80211_reassemble_add(struct ieee80211_sub_if_data * sdata,unsigned int frag,unsigned int seq,int rx_queue,struct sk_buff ** skb)802 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
803 unsigned int frag, unsigned int seq, int rx_queue,
804 struct sk_buff **skb)
805 {
806 struct ieee80211_fragment_entry *entry;
807 int idx;
808
809 idx = sdata->fragment_next;
810 entry = &sdata->fragments[sdata->fragment_next++];
811 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
812 sdata->fragment_next = 0;
813
814 if (!skb_queue_empty(&entry->skb_list)) {
815 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
816 struct ieee80211_hdr *hdr =
817 (struct ieee80211_hdr *) entry->skb_list.next->data;
818 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
819 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
820 "addr1=%pM addr2=%pM\n",
821 sdata->dev->name, idx,
822 jiffies - entry->first_frag_time, entry->seq,
823 entry->last_frag, hdr->addr1, hdr->addr2);
824 #endif
825 __skb_queue_purge(&entry->skb_list);
826 }
827
828 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
829 *skb = NULL;
830 entry->first_frag_time = jiffies;
831 entry->seq = seq;
832 entry->rx_queue = rx_queue;
833 entry->last_frag = frag;
834 entry->ccmp = 0;
835 entry->extra_len = 0;
836
837 return entry;
838 }
839
840 static inline struct ieee80211_fragment_entry *
ieee80211_reassemble_find(struct ieee80211_sub_if_data * sdata,unsigned int frag,unsigned int seq,int rx_queue,struct ieee80211_hdr * hdr)841 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
842 unsigned int frag, unsigned int seq,
843 int rx_queue, struct ieee80211_hdr *hdr)
844 {
845 struct ieee80211_fragment_entry *entry;
846 int i, idx;
847
848 idx = sdata->fragment_next;
849 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
850 struct ieee80211_hdr *f_hdr;
851
852 idx--;
853 if (idx < 0)
854 idx = IEEE80211_FRAGMENT_MAX - 1;
855
856 entry = &sdata->fragments[idx];
857 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
858 entry->rx_queue != rx_queue ||
859 entry->last_frag + 1 != frag)
860 continue;
861
862 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
863
864 /*
865 * Check ftype and addresses are equal, else check next fragment
866 */
867 if (((hdr->frame_control ^ f_hdr->frame_control) &
868 cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
869 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
870 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
871 continue;
872
873 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
874 __skb_queue_purge(&entry->skb_list);
875 continue;
876 }
877 return entry;
878 }
879
880 return NULL;
881 }
882
883 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_defragment(struct ieee80211_rx_data * rx)884 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
885 {
886 struct ieee80211_hdr *hdr;
887 u16 sc;
888 __le16 fc;
889 unsigned int frag, seq;
890 struct ieee80211_fragment_entry *entry;
891 struct sk_buff *skb;
892
893 hdr = (struct ieee80211_hdr *)rx->skb->data;
894 fc = hdr->frame_control;
895 sc = le16_to_cpu(hdr->seq_ctrl);
896 frag = sc & IEEE80211_SCTL_FRAG;
897
898 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
899 (rx->skb)->len < 24 ||
900 is_multicast_ether_addr(hdr->addr1))) {
901 /* not fragmented */
902 goto out;
903 }
904 I802_DEBUG_INC(rx->local->rx_handlers_fragments);
905
906 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
907
908 if (frag == 0) {
909 /* This is the first fragment of a new frame. */
910 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
911 rx->queue, &(rx->skb));
912 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
913 ieee80211_has_protected(fc)) {
914 /* Store CCMP PN so that we can verify that the next
915 * fragment has a sequential PN value. */
916 entry->ccmp = 1;
917 memcpy(entry->last_pn,
918 rx->key->u.ccmp.rx_pn[rx->queue],
919 CCMP_PN_LEN);
920 }
921 return RX_QUEUED;
922 }
923
924 /* This is a fragment for a frame that should already be pending in
925 * fragment cache. Add this fragment to the end of the pending entry.
926 */
927 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
928 if (!entry) {
929 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
930 return RX_DROP_MONITOR;
931 }
932
933 /* Verify that MPDUs within one MSDU have sequential PN values.
934 * (IEEE 802.11i, 8.3.3.4.5) */
935 if (entry->ccmp) {
936 int i;
937 u8 pn[CCMP_PN_LEN], *rpn;
938 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
939 return RX_DROP_UNUSABLE;
940 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
941 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
942 pn[i]++;
943 if (pn[i])
944 break;
945 }
946 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
947 if (memcmp(pn, rpn, CCMP_PN_LEN))
948 return RX_DROP_UNUSABLE;
949 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
950 }
951
952 skb_pull(rx->skb, ieee80211_hdrlen(fc));
953 __skb_queue_tail(&entry->skb_list, rx->skb);
954 entry->last_frag = frag;
955 entry->extra_len += rx->skb->len;
956 if (ieee80211_has_morefrags(fc)) {
957 rx->skb = NULL;
958 return RX_QUEUED;
959 }
960
961 rx->skb = __skb_dequeue(&entry->skb_list);
962 if (skb_tailroom(rx->skb) < entry->extra_len) {
963 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
964 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
965 GFP_ATOMIC))) {
966 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
967 __skb_queue_purge(&entry->skb_list);
968 return RX_DROP_UNUSABLE;
969 }
970 }
971 while ((skb = __skb_dequeue(&entry->skb_list))) {
972 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
973 dev_kfree_skb(skb);
974 }
975
976 /* Complete frame has been reassembled - process it now */
977 rx->flags |= IEEE80211_RX_FRAGMENTED;
978
979 out:
980 if (rx->sta)
981 rx->sta->rx_packets++;
982 if (is_multicast_ether_addr(hdr->addr1))
983 rx->local->dot11MulticastReceivedFrameCount++;
984 else
985 ieee80211_led_rx(rx->local);
986 return RX_CONTINUE;
987 }
988
989 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_ps_poll(struct ieee80211_rx_data * rx)990 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
991 {
992 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
993 struct sk_buff *skb;
994 int no_pending_pkts;
995 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
996
997 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
998 !(rx->flags & IEEE80211_RX_RA_MATCH)))
999 return RX_CONTINUE;
1000
1001 if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1002 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1003 return RX_DROP_UNUSABLE;
1004
1005 skb = skb_dequeue(&rx->sta->tx_filtered);
1006 if (!skb) {
1007 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1008 if (skb)
1009 rx->local->total_ps_buffered--;
1010 }
1011 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1012 skb_queue_empty(&rx->sta->ps_tx_buf);
1013
1014 if (skb) {
1015 struct ieee80211_hdr *hdr =
1016 (struct ieee80211_hdr *) skb->data;
1017
1018 /*
1019 * Tell TX path to send one frame even though the STA may
1020 * still remain is PS mode after this frame exchange.
1021 */
1022 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1023
1024 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1025 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1026 rx->sta->sta.addr, rx->sta->sta.aid,
1027 skb_queue_len(&rx->sta->ps_tx_buf));
1028 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1029
1030 /* Use MoreData flag to indicate whether there are more
1031 * buffered frames for this STA */
1032 if (no_pending_pkts)
1033 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1034 else
1035 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1036
1037 dev_queue_xmit(skb);
1038
1039 if (no_pending_pkts)
1040 sta_info_clear_tim_bit(rx->sta);
1041 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1042 } else if (!rx->sent_ps_buffered) {
1043 /*
1044 * FIXME: This can be the result of a race condition between
1045 * us expiring a frame and the station polling for it.
1046 * Should we send it a null-func frame indicating we
1047 * have nothing buffered for it?
1048 */
1049 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1050 "though there are no buffered frames for it\n",
1051 rx->dev->name, rx->sta->sta.addr);
1052 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1053 }
1054
1055 /* Free PS Poll skb here instead of returning RX_DROP that would
1056 * count as an dropped frame. */
1057 dev_kfree_skb(rx->skb);
1058
1059 return RX_QUEUED;
1060 }
1061
1062 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data * rx)1063 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1064 {
1065 u8 *data = rx->skb->data;
1066 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1067
1068 if (!ieee80211_is_data_qos(hdr->frame_control))
1069 return RX_CONTINUE;
1070
1071 /* remove the qos control field, update frame type and meta-data */
1072 memmove(data + IEEE80211_QOS_CTL_LEN, data,
1073 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1074 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1075 /* change frame type to non QOS */
1076 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1077
1078 return RX_CONTINUE;
1079 }
1080
1081 static int
ieee80211_802_1x_port_control(struct ieee80211_rx_data * rx)1082 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1083 {
1084 if (unlikely(!rx->sta ||
1085 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1086 return -EACCES;
1087
1088 return 0;
1089 }
1090
1091 static int
ieee80211_drop_unencrypted(struct ieee80211_rx_data * rx,__le16 fc)1092 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1093 {
1094 /*
1095 * Pass through unencrypted frames if the hardware has
1096 * decrypted them already.
1097 */
1098 if (rx->status->flag & RX_FLAG_DECRYPTED)
1099 return 0;
1100
1101 /* Drop unencrypted frames if key is set. */
1102 if (unlikely(!ieee80211_has_protected(fc) &&
1103 !ieee80211_is_nullfunc(fc) &&
1104 (rx->key || rx->sdata->drop_unencrypted)))
1105 return -EACCES;
1106
1107 return 0;
1108 }
1109
1110 static int
ieee80211_data_to_8023(struct ieee80211_rx_data * rx)1111 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1112 {
1113 struct net_device *dev = rx->dev;
1114 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1115 u16 hdrlen, ethertype;
1116 u8 *payload;
1117 u8 dst[ETH_ALEN];
1118 u8 src[ETH_ALEN] __aligned(2);
1119 struct sk_buff *skb = rx->skb;
1120 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1121
1122 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1123 return -1;
1124
1125 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1126
1127 /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1128 * header
1129 * IEEE 802.11 address fields:
1130 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1131 * 0 0 DA SA BSSID n/a
1132 * 0 1 DA BSSID SA n/a
1133 * 1 0 BSSID SA DA n/a
1134 * 1 1 RA TA DA SA
1135 */
1136 memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1137 memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1138
1139 switch (hdr->frame_control &
1140 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1141 case __constant_cpu_to_le16(IEEE80211_FCTL_TODS):
1142 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1143 sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1144 return -1;
1145 break;
1146 case __constant_cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1147 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1148 sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1149 return -1;
1150 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1151 struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1152 (skb->data + hdrlen);
1153 hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1154 if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1155 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1156 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1157 }
1158 }
1159 break;
1160 case __constant_cpu_to_le16(IEEE80211_FCTL_FROMDS):
1161 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1162 (is_multicast_ether_addr(dst) &&
1163 !compare_ether_addr(src, dev->dev_addr)))
1164 return -1;
1165 break;
1166 case __constant_cpu_to_le16(0):
1167 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1168 return -1;
1169 break;
1170 }
1171
1172 if (unlikely(skb->len - hdrlen < 8))
1173 return -1;
1174
1175 payload = skb->data + hdrlen;
1176 ethertype = (payload[6] << 8) | payload[7];
1177
1178 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1179 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1180 compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1181 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1182 * replace EtherType */
1183 skb_pull(skb, hdrlen + 6);
1184 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1185 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1186 } else {
1187 struct ethhdr *ehdr;
1188 __be16 len;
1189
1190 skb_pull(skb, hdrlen);
1191 len = htons(skb->len);
1192 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1193 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1194 memcpy(ehdr->h_source, src, ETH_ALEN);
1195 ehdr->h_proto = len;
1196 }
1197 return 0;
1198 }
1199
1200 /*
1201 * requires that rx->skb is a frame with ethernet header
1202 */
ieee80211_frame_allowed(struct ieee80211_rx_data * rx,__le16 fc)1203 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1204 {
1205 static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1206 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1207 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1208
1209 /*
1210 * Allow EAPOL frames to us/the PAE group address regardless
1211 * of whether the frame was encrypted or not.
1212 */
1213 if (ehdr->h_proto == htons(ETH_P_PAE) &&
1214 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1215 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1216 return true;
1217
1218 if (ieee80211_802_1x_port_control(rx) ||
1219 ieee80211_drop_unencrypted(rx, fc))
1220 return false;
1221
1222 return true;
1223 }
1224
1225 /*
1226 * requires that rx->skb is a frame with ethernet header
1227 */
1228 static void
ieee80211_deliver_skb(struct ieee80211_rx_data * rx)1229 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1230 {
1231 struct net_device *dev = rx->dev;
1232 struct ieee80211_local *local = rx->local;
1233 struct sk_buff *skb, *xmit_skb;
1234 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1235 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1236 struct sta_info *dsta;
1237
1238 skb = rx->skb;
1239 xmit_skb = NULL;
1240
1241 if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1242 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1243 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1244 (rx->flags & IEEE80211_RX_RA_MATCH)) {
1245 if (is_multicast_ether_addr(ehdr->h_dest)) {
1246 /*
1247 * send multicast frames both to higher layers in
1248 * local net stack and back to the wireless medium
1249 */
1250 xmit_skb = skb_copy(skb, GFP_ATOMIC);
1251 if (!xmit_skb && net_ratelimit())
1252 printk(KERN_DEBUG "%s: failed to clone "
1253 "multicast frame\n", dev->name);
1254 } else {
1255 dsta = sta_info_get(local, skb->data);
1256 if (dsta && dsta->sdata->dev == dev) {
1257 /*
1258 * The destination station is associated to
1259 * this AP (in this VLAN), so send the frame
1260 * directly to it and do not pass it to local
1261 * net stack.
1262 */
1263 xmit_skb = skb;
1264 skb = NULL;
1265 }
1266 }
1267 }
1268
1269 if (skb) {
1270 /* deliver to local stack */
1271 skb->protocol = eth_type_trans(skb, dev);
1272 memset(skb->cb, 0, sizeof(skb->cb));
1273 netif_rx(skb);
1274 }
1275
1276 if (xmit_skb) {
1277 /* send to wireless media */
1278 xmit_skb->protocol = htons(ETH_P_802_3);
1279 skb_reset_network_header(xmit_skb);
1280 skb_reset_mac_header(xmit_skb);
1281 dev_queue_xmit(xmit_skb);
1282 }
1283 }
1284
1285 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_amsdu(struct ieee80211_rx_data * rx)1286 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1287 {
1288 struct net_device *dev = rx->dev;
1289 struct ieee80211_local *local = rx->local;
1290 u16 ethertype;
1291 u8 *payload;
1292 struct sk_buff *skb = rx->skb, *frame = NULL;
1293 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1294 __le16 fc = hdr->frame_control;
1295 const struct ethhdr *eth;
1296 int remaining, err;
1297 u8 dst[ETH_ALEN];
1298 u8 src[ETH_ALEN];
1299
1300 if (unlikely(!ieee80211_is_data(fc)))
1301 return RX_CONTINUE;
1302
1303 if (unlikely(!ieee80211_is_data_present(fc)))
1304 return RX_DROP_MONITOR;
1305
1306 if (!(rx->flags & IEEE80211_RX_AMSDU))
1307 return RX_CONTINUE;
1308
1309 err = ieee80211_data_to_8023(rx);
1310 if (unlikely(err))
1311 return RX_DROP_UNUSABLE;
1312
1313 skb->dev = dev;
1314
1315 dev->stats.rx_packets++;
1316 dev->stats.rx_bytes += skb->len;
1317
1318 /* skip the wrapping header */
1319 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1320 if (!eth)
1321 return RX_DROP_UNUSABLE;
1322
1323 while (skb != frame) {
1324 u8 padding;
1325 __be16 len = eth->h_proto;
1326 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1327
1328 remaining = skb->len;
1329 memcpy(dst, eth->h_dest, ETH_ALEN);
1330 memcpy(src, eth->h_source, ETH_ALEN);
1331
1332 padding = ((4 - subframe_len) & 0x3);
1333 /* the last MSDU has no padding */
1334 if (subframe_len > remaining)
1335 return RX_DROP_UNUSABLE;
1336
1337 skb_pull(skb, sizeof(struct ethhdr));
1338 /* if last subframe reuse skb */
1339 if (remaining <= subframe_len + padding)
1340 frame = skb;
1341 else {
1342 frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1343 subframe_len);
1344
1345 if (frame == NULL)
1346 return RX_DROP_UNUSABLE;
1347
1348 skb_reserve(frame, local->hw.extra_tx_headroom +
1349 sizeof(struct ethhdr));
1350 memcpy(skb_put(frame, ntohs(len)), skb->data,
1351 ntohs(len));
1352
1353 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1354 padding);
1355 if (!eth) {
1356 dev_kfree_skb(frame);
1357 return RX_DROP_UNUSABLE;
1358 }
1359 }
1360
1361 skb_reset_network_header(frame);
1362 frame->dev = dev;
1363 frame->priority = skb->priority;
1364 rx->skb = frame;
1365
1366 payload = frame->data;
1367 ethertype = (payload[6] << 8) | payload[7];
1368
1369 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1370 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1371 compare_ether_addr(payload,
1372 bridge_tunnel_header) == 0)) {
1373 /* remove RFC1042 or Bridge-Tunnel
1374 * encapsulation and replace EtherType */
1375 skb_pull(frame, 6);
1376 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1377 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1378 } else {
1379 memcpy(skb_push(frame, sizeof(__be16)),
1380 &len, sizeof(__be16));
1381 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1382 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1383 }
1384
1385 if (!ieee80211_frame_allowed(rx, fc)) {
1386 if (skb == frame) /* last frame */
1387 return RX_DROP_UNUSABLE;
1388 dev_kfree_skb(frame);
1389 continue;
1390 }
1391
1392 ieee80211_deliver_skb(rx);
1393 }
1394
1395 return RX_QUEUED;
1396 }
1397
1398 #ifdef CONFIG_MAC80211_MESH
1399 static ieee80211_rx_result
ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data * rx)1400 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1401 {
1402 struct ieee80211_hdr *hdr;
1403 struct ieee80211s_hdr *mesh_hdr;
1404 unsigned int hdrlen;
1405 struct sk_buff *skb = rx->skb, *fwd_skb;
1406
1407 hdr = (struct ieee80211_hdr *) skb->data;
1408 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1409 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1410
1411 if (!ieee80211_is_data(hdr->frame_control))
1412 return RX_CONTINUE;
1413
1414 if (!mesh_hdr->ttl)
1415 /* illegal frame */
1416 return RX_DROP_MONITOR;
1417
1418 if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1419 struct ieee80211_sub_if_data *sdata;
1420 struct mesh_path *mppath;
1421
1422 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1423 rcu_read_lock();
1424 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1425 if (!mppath) {
1426 mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1427 } else {
1428 spin_lock_bh(&mppath->state_lock);
1429 mppath->exp_time = jiffies;
1430 if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1431 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1432 spin_unlock_bh(&mppath->state_lock);
1433 }
1434 rcu_read_unlock();
1435 }
1436
1437 if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1438 return RX_CONTINUE;
1439
1440 mesh_hdr->ttl--;
1441
1442 if (rx->flags & IEEE80211_RX_RA_MATCH) {
1443 if (!mesh_hdr->ttl)
1444 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1445 dropped_frames_ttl);
1446 else {
1447 struct ieee80211_hdr *fwd_hdr;
1448 fwd_skb = skb_copy(skb, GFP_ATOMIC);
1449
1450 if (!fwd_skb && net_ratelimit())
1451 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1452 rx->dev->name);
1453
1454 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
1455 /*
1456 * Save TA to addr1 to send TA a path error if a
1457 * suitable next hop is not found
1458 */
1459 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1460 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1461 fwd_skb->dev = rx->local->mdev;
1462 fwd_skb->iif = rx->dev->ifindex;
1463 dev_queue_xmit(fwd_skb);
1464 }
1465 }
1466
1467 if (is_multicast_ether_addr(hdr->addr3) ||
1468 rx->dev->flags & IFF_PROMISC)
1469 return RX_CONTINUE;
1470 else
1471 return RX_DROP_MONITOR;
1472 }
1473 #endif
1474
1475 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_data(struct ieee80211_rx_data * rx)1476 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1477 {
1478 struct net_device *dev = rx->dev;
1479 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1480 __le16 fc = hdr->frame_control;
1481 int err;
1482
1483 if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1484 return RX_CONTINUE;
1485
1486 if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1487 return RX_DROP_MONITOR;
1488
1489 err = ieee80211_data_to_8023(rx);
1490 if (unlikely(err))
1491 return RX_DROP_UNUSABLE;
1492
1493 if (!ieee80211_frame_allowed(rx, fc))
1494 return RX_DROP_MONITOR;
1495
1496 rx->skb->dev = dev;
1497
1498 dev->stats.rx_packets++;
1499 dev->stats.rx_bytes += rx->skb->len;
1500
1501 ieee80211_deliver_skb(rx);
1502
1503 return RX_QUEUED;
1504 }
1505
1506 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_ctrl(struct ieee80211_rx_data * rx)1507 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1508 {
1509 struct ieee80211_local *local = rx->local;
1510 struct ieee80211_hw *hw = &local->hw;
1511 struct sk_buff *skb = rx->skb;
1512 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1513 struct tid_ampdu_rx *tid_agg_rx;
1514 u16 start_seq_num;
1515 u16 tid;
1516
1517 if (likely(!ieee80211_is_ctl(bar->frame_control)))
1518 return RX_CONTINUE;
1519
1520 if (ieee80211_is_back_req(bar->frame_control)) {
1521 if (!rx->sta)
1522 return RX_CONTINUE;
1523 tid = le16_to_cpu(bar->control) >> 12;
1524 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1525 != HT_AGG_STATE_OPERATIONAL)
1526 return RX_CONTINUE;
1527 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1528
1529 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1530
1531 /* reset session timer */
1532 if (tid_agg_rx->timeout) {
1533 unsigned long expires =
1534 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1535 mod_timer(&tid_agg_rx->session_timer, expires);
1536 }
1537
1538 /* manage reordering buffer according to requested */
1539 /* sequence number */
1540 rcu_read_lock();
1541 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1542 start_seq_num, 1);
1543 rcu_read_unlock();
1544 return RX_DROP_UNUSABLE;
1545 }
1546
1547 return RX_CONTINUE;
1548 }
1549
1550 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_action(struct ieee80211_rx_data * rx)1551 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1552 {
1553 struct ieee80211_local *local = rx->local;
1554 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1555 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1556 int len = rx->skb->len;
1557
1558 if (!ieee80211_is_action(mgmt->frame_control))
1559 return RX_CONTINUE;
1560
1561 if (!rx->sta)
1562 return RX_DROP_MONITOR;
1563
1564 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1565 return RX_DROP_MONITOR;
1566
1567 /* all categories we currently handle have action_code */
1568 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1569 return RX_DROP_MONITOR;
1570
1571 switch (mgmt->u.action.category) {
1572 case WLAN_CATEGORY_BACK:
1573 switch (mgmt->u.action.u.addba_req.action_code) {
1574 case WLAN_ACTION_ADDBA_REQ:
1575 if (len < (IEEE80211_MIN_ACTION_SIZE +
1576 sizeof(mgmt->u.action.u.addba_req)))
1577 return RX_DROP_MONITOR;
1578 ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1579 break;
1580 case WLAN_ACTION_ADDBA_RESP:
1581 if (len < (IEEE80211_MIN_ACTION_SIZE +
1582 sizeof(mgmt->u.action.u.addba_resp)))
1583 return RX_DROP_MONITOR;
1584 ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1585 break;
1586 case WLAN_ACTION_DELBA:
1587 if (len < (IEEE80211_MIN_ACTION_SIZE +
1588 sizeof(mgmt->u.action.u.delba)))
1589 return RX_DROP_MONITOR;
1590 ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1591 break;
1592 }
1593 break;
1594 case WLAN_CATEGORY_SPECTRUM_MGMT:
1595 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1596 return RX_DROP_MONITOR;
1597 switch (mgmt->u.action.u.measurement.action_code) {
1598 case WLAN_ACTION_SPCT_MSR_REQ:
1599 if (len < (IEEE80211_MIN_ACTION_SIZE +
1600 sizeof(mgmt->u.action.u.measurement)))
1601 return RX_DROP_MONITOR;
1602 ieee80211_process_measurement_req(sdata, mgmt, len);
1603 break;
1604 }
1605 break;
1606 default:
1607 return RX_CONTINUE;
1608 }
1609
1610 rx->sta->rx_packets++;
1611 dev_kfree_skb(rx->skb);
1612 return RX_QUEUED;
1613 }
1614
1615 static ieee80211_rx_result debug_noinline
ieee80211_rx_h_mgmt(struct ieee80211_rx_data * rx)1616 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1617 {
1618 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1619
1620 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1621 return RX_DROP_MONITOR;
1622
1623 if (ieee80211_vif_is_mesh(&sdata->vif))
1624 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1625
1626 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1627 sdata->vif.type != NL80211_IFTYPE_ADHOC)
1628 return RX_DROP_MONITOR;
1629
1630 if (sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)
1631 return RX_DROP_MONITOR;
1632
1633 ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1634 return RX_QUEUED;
1635 }
1636
ieee80211_rx_michael_mic_report(struct net_device * dev,struct ieee80211_hdr * hdr,struct ieee80211_rx_data * rx)1637 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1638 struct ieee80211_hdr *hdr,
1639 struct ieee80211_rx_data *rx)
1640 {
1641 int keyidx;
1642 unsigned int hdrlen;
1643
1644 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1645 if (rx->skb->len >= hdrlen + 4)
1646 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1647 else
1648 keyidx = -1;
1649
1650 if (!rx->sta) {
1651 /*
1652 * Some hardware seem to generate incorrect Michael MIC
1653 * reports; ignore them to avoid triggering countermeasures.
1654 */
1655 goto ignore;
1656 }
1657
1658 if (!ieee80211_has_protected(hdr->frame_control))
1659 goto ignore;
1660
1661 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1662 /*
1663 * APs with pairwise keys should never receive Michael MIC
1664 * errors for non-zero keyidx because these are reserved for
1665 * group keys and only the AP is sending real multicast
1666 * frames in the BSS.
1667 */
1668 goto ignore;
1669 }
1670
1671 if (!ieee80211_is_data(hdr->frame_control) &&
1672 !ieee80211_is_auth(hdr->frame_control))
1673 goto ignore;
1674
1675 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1676 ignore:
1677 dev_kfree_skb(rx->skb);
1678 rx->skb = NULL;
1679 }
1680
1681 /* TODO: use IEEE80211_RX_FRAGMENTED */
ieee80211_rx_cooked_monitor(struct ieee80211_rx_data * rx)1682 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1683 {
1684 struct ieee80211_sub_if_data *sdata;
1685 struct ieee80211_local *local = rx->local;
1686 struct ieee80211_rtap_hdr {
1687 struct ieee80211_radiotap_header hdr;
1688 u8 flags;
1689 u8 rate;
1690 __le16 chan_freq;
1691 __le16 chan_flags;
1692 } __attribute__ ((packed)) *rthdr;
1693 struct sk_buff *skb = rx->skb, *skb2;
1694 struct net_device *prev_dev = NULL;
1695 struct ieee80211_rx_status *status = rx->status;
1696
1697 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1698 goto out_free_skb;
1699
1700 if (skb_headroom(skb) < sizeof(*rthdr) &&
1701 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1702 goto out_free_skb;
1703
1704 rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1705 memset(rthdr, 0, sizeof(*rthdr));
1706 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1707 rthdr->hdr.it_present =
1708 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1709 (1 << IEEE80211_RADIOTAP_RATE) |
1710 (1 << IEEE80211_RADIOTAP_CHANNEL));
1711
1712 rthdr->rate = rx->rate->bitrate / 5;
1713 rthdr->chan_freq = cpu_to_le16(status->freq);
1714
1715 if (status->band == IEEE80211_BAND_5GHZ)
1716 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1717 IEEE80211_CHAN_5GHZ);
1718 else
1719 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1720 IEEE80211_CHAN_2GHZ);
1721
1722 skb_set_mac_header(skb, 0);
1723 skb->ip_summed = CHECKSUM_UNNECESSARY;
1724 skb->pkt_type = PACKET_OTHERHOST;
1725 skb->protocol = htons(ETH_P_802_2);
1726
1727 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1728 if (!netif_running(sdata->dev))
1729 continue;
1730
1731 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1732 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1733 continue;
1734
1735 if (prev_dev) {
1736 skb2 = skb_clone(skb, GFP_ATOMIC);
1737 if (skb2) {
1738 skb2->dev = prev_dev;
1739 netif_rx(skb2);
1740 }
1741 }
1742
1743 prev_dev = sdata->dev;
1744 sdata->dev->stats.rx_packets++;
1745 sdata->dev->stats.rx_bytes += skb->len;
1746 }
1747
1748 if (prev_dev) {
1749 skb->dev = prev_dev;
1750 netif_rx(skb);
1751 skb = NULL;
1752 } else
1753 goto out_free_skb;
1754
1755 rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1756 return;
1757
1758 out_free_skb:
1759 dev_kfree_skb(skb);
1760 }
1761
1762
ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data * sdata,struct ieee80211_rx_data * rx,struct sk_buff * skb)1763 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1764 struct ieee80211_rx_data *rx,
1765 struct sk_buff *skb)
1766 {
1767 ieee80211_rx_result res = RX_DROP_MONITOR;
1768
1769 rx->skb = skb;
1770 rx->sdata = sdata;
1771 rx->dev = sdata->dev;
1772
1773 #define CALL_RXH(rxh) \
1774 do { \
1775 res = rxh(rx); \
1776 if (res != RX_CONTINUE) \
1777 goto rxh_done; \
1778 } while (0);
1779
1780 CALL_RXH(ieee80211_rx_h_passive_scan)
1781 CALL_RXH(ieee80211_rx_h_check)
1782 CALL_RXH(ieee80211_rx_h_decrypt)
1783 CALL_RXH(ieee80211_rx_h_sta_process)
1784 CALL_RXH(ieee80211_rx_h_defragment)
1785 CALL_RXH(ieee80211_rx_h_ps_poll)
1786 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1787 /* must be after MMIC verify so header is counted in MPDU mic */
1788 CALL_RXH(ieee80211_rx_h_remove_qos_control)
1789 CALL_RXH(ieee80211_rx_h_amsdu)
1790 #ifdef CONFIG_MAC80211_MESH
1791 if (ieee80211_vif_is_mesh(&sdata->vif))
1792 CALL_RXH(ieee80211_rx_h_mesh_fwding);
1793 #endif
1794 CALL_RXH(ieee80211_rx_h_data)
1795 CALL_RXH(ieee80211_rx_h_ctrl)
1796 CALL_RXH(ieee80211_rx_h_action)
1797 CALL_RXH(ieee80211_rx_h_mgmt)
1798
1799 #undef CALL_RXH
1800
1801 rxh_done:
1802 switch (res) {
1803 case RX_DROP_MONITOR:
1804 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1805 if (rx->sta)
1806 rx->sta->rx_dropped++;
1807 /* fall through */
1808 case RX_CONTINUE:
1809 ieee80211_rx_cooked_monitor(rx);
1810 break;
1811 case RX_DROP_UNUSABLE:
1812 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1813 if (rx->sta)
1814 rx->sta->rx_dropped++;
1815 dev_kfree_skb(rx->skb);
1816 break;
1817 case RX_QUEUED:
1818 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1819 break;
1820 }
1821 }
1822
1823 /* main receive path */
1824
prepare_for_handlers(struct ieee80211_sub_if_data * sdata,u8 * bssid,struct ieee80211_rx_data * rx,struct ieee80211_hdr * hdr)1825 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1826 u8 *bssid, struct ieee80211_rx_data *rx,
1827 struct ieee80211_hdr *hdr)
1828 {
1829 int multicast = is_multicast_ether_addr(hdr->addr1);
1830
1831 switch (sdata->vif.type) {
1832 case NL80211_IFTYPE_STATION:
1833 if (!bssid)
1834 return 0;
1835 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1836 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1837 return 0;
1838 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1839 } else if (!multicast &&
1840 compare_ether_addr(sdata->dev->dev_addr,
1841 hdr->addr1) != 0) {
1842 if (!(sdata->dev->flags & IFF_PROMISC))
1843 return 0;
1844 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1845 }
1846 break;
1847 case NL80211_IFTYPE_ADHOC:
1848 if (!bssid)
1849 return 0;
1850 if (ieee80211_is_beacon(hdr->frame_control)) {
1851 return 1;
1852 }
1853 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1854 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1855 return 0;
1856 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1857 } else if (!multicast &&
1858 compare_ether_addr(sdata->dev->dev_addr,
1859 hdr->addr1) != 0) {
1860 if (!(sdata->dev->flags & IFF_PROMISC))
1861 return 0;
1862 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1863 } else if (!rx->sta) {
1864 int rate_idx;
1865 if (rx->status->flag & RX_FLAG_HT)
1866 rate_idx = 0; /* TODO: HT rates */
1867 else
1868 rate_idx = rx->status->rate_idx;
1869 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
1870 BIT(rate_idx));
1871 }
1872 break;
1873 case NL80211_IFTYPE_MESH_POINT:
1874 if (!multicast &&
1875 compare_ether_addr(sdata->dev->dev_addr,
1876 hdr->addr1) != 0) {
1877 if (!(sdata->dev->flags & IFF_PROMISC))
1878 return 0;
1879
1880 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1881 }
1882 break;
1883 case NL80211_IFTYPE_AP_VLAN:
1884 case NL80211_IFTYPE_AP:
1885 if (!bssid) {
1886 if (compare_ether_addr(sdata->dev->dev_addr,
1887 hdr->addr1))
1888 return 0;
1889 } else if (!ieee80211_bssid_match(bssid,
1890 sdata->dev->dev_addr)) {
1891 if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1892 return 0;
1893 rx->flags &= ~IEEE80211_RX_RA_MATCH;
1894 }
1895 break;
1896 case NL80211_IFTYPE_WDS:
1897 if (bssid || !ieee80211_is_data(hdr->frame_control))
1898 return 0;
1899 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1900 return 0;
1901 break;
1902 case NL80211_IFTYPE_MONITOR:
1903 /* take everything */
1904 break;
1905 case NL80211_IFTYPE_UNSPECIFIED:
1906 case __NL80211_IFTYPE_AFTER_LAST:
1907 /* should never get here */
1908 WARN_ON(1);
1909 break;
1910 }
1911
1912 return 1;
1913 }
1914
1915 /*
1916 * This is the actual Rx frames handler. as it blongs to Rx path it must
1917 * be called with rcu_read_lock protection.
1918 */
__ieee80211_rx_handle_packet(struct ieee80211_hw * hw,struct sk_buff * skb,struct ieee80211_rx_status * status,struct ieee80211_rate * rate)1919 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1920 struct sk_buff *skb,
1921 struct ieee80211_rx_status *status,
1922 struct ieee80211_rate *rate)
1923 {
1924 struct ieee80211_local *local = hw_to_local(hw);
1925 struct ieee80211_sub_if_data *sdata;
1926 struct ieee80211_hdr *hdr;
1927 struct ieee80211_rx_data rx;
1928 int prepares;
1929 struct ieee80211_sub_if_data *prev = NULL;
1930 struct sk_buff *skb_new;
1931 u8 *bssid;
1932
1933 hdr = (struct ieee80211_hdr *)skb->data;
1934 memset(&rx, 0, sizeof(rx));
1935 rx.skb = skb;
1936 rx.local = local;
1937
1938 rx.status = status;
1939 rx.rate = rate;
1940
1941 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
1942 local->dot11ReceivedFragmentCount++;
1943
1944 rx.sta = sta_info_get(local, hdr->addr2);
1945 if (rx.sta) {
1946 rx.sdata = rx.sta->sdata;
1947 rx.dev = rx.sta->sdata->dev;
1948 }
1949
1950 if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1951 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1952 return;
1953 }
1954
1955 if (unlikely(local->sw_scanning || local->hw_scanning))
1956 rx.flags |= IEEE80211_RX_IN_SCAN;
1957
1958 ieee80211_parse_qos(&rx);
1959 ieee80211_verify_ip_alignment(&rx);
1960
1961 skb = rx.skb;
1962
1963 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1964 if (!netif_running(sdata->dev))
1965 continue;
1966
1967 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
1968 continue;
1969
1970 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1971 rx.flags |= IEEE80211_RX_RA_MATCH;
1972 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1973
1974 if (!prepares)
1975 continue;
1976
1977 /*
1978 * frame is destined for this interface, but if it's not
1979 * also for the previous one we handle that after the
1980 * loop to avoid copying the SKB once too much
1981 */
1982
1983 if (!prev) {
1984 prev = sdata;
1985 continue;
1986 }
1987
1988 /*
1989 * frame was destined for the previous interface
1990 * so invoke RX handlers for it
1991 */
1992
1993 skb_new = skb_copy(skb, GFP_ATOMIC);
1994 if (!skb_new) {
1995 if (net_ratelimit())
1996 printk(KERN_DEBUG "%s: failed to copy "
1997 "multicast frame for %s\n",
1998 wiphy_name(local->hw.wiphy),
1999 prev->dev->name);
2000 continue;
2001 }
2002 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2003 prev = sdata;
2004 }
2005 if (prev)
2006 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2007 else
2008 dev_kfree_skb(skb);
2009 }
2010
2011 #define SEQ_MODULO 0x1000
2012 #define SEQ_MASK 0xfff
2013
seq_less(u16 sq1,u16 sq2)2014 static inline int seq_less(u16 sq1, u16 sq2)
2015 {
2016 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2017 }
2018
seq_inc(u16 sq)2019 static inline u16 seq_inc(u16 sq)
2020 {
2021 return (sq + 1) & SEQ_MASK;
2022 }
2023
seq_sub(u16 sq1,u16 sq2)2024 static inline u16 seq_sub(u16 sq1, u16 sq2)
2025 {
2026 return (sq1 - sq2) & SEQ_MASK;
2027 }
2028
2029
2030 /*
2031 * As it function blongs to Rx path it must be called with
2032 * the proper rcu_read_lock protection for its flow.
2033 */
ieee80211_sta_manage_reorder_buf(struct ieee80211_hw * hw,struct tid_ampdu_rx * tid_agg_rx,struct sk_buff * skb,u16 mpdu_seq_num,int bar_req)2034 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2035 struct tid_ampdu_rx *tid_agg_rx,
2036 struct sk_buff *skb,
2037 u16 mpdu_seq_num,
2038 int bar_req)
2039 {
2040 struct ieee80211_local *local = hw_to_local(hw);
2041 struct ieee80211_rx_status status;
2042 u16 head_seq_num, buf_size;
2043 int index;
2044 struct ieee80211_supported_band *sband;
2045 struct ieee80211_rate *rate;
2046
2047 buf_size = tid_agg_rx->buf_size;
2048 head_seq_num = tid_agg_rx->head_seq_num;
2049
2050 /* frame with out of date sequence number */
2051 if (seq_less(mpdu_seq_num, head_seq_num)) {
2052 dev_kfree_skb(skb);
2053 return 1;
2054 }
2055
2056 /* if frame sequence number exceeds our buffering window size or
2057 * block Ack Request arrived - release stored frames */
2058 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2059 /* new head to the ordering buffer */
2060 if (bar_req)
2061 head_seq_num = mpdu_seq_num;
2062 else
2063 head_seq_num =
2064 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2065 /* release stored frames up to new head to stack */
2066 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2067 index = seq_sub(tid_agg_rx->head_seq_num,
2068 tid_agg_rx->ssn)
2069 % tid_agg_rx->buf_size;
2070
2071 if (tid_agg_rx->reorder_buf[index]) {
2072 /* release the reordered frames to stack */
2073 memcpy(&status,
2074 tid_agg_rx->reorder_buf[index]->cb,
2075 sizeof(status));
2076 sband = local->hw.wiphy->bands[status.band];
2077 if (status.flag & RX_FLAG_HT) {
2078 /* TODO: HT rates */
2079 rate = sband->bitrates;
2080 } else {
2081 rate = &sband->bitrates
2082 [status.rate_idx];
2083 }
2084 __ieee80211_rx_handle_packet(hw,
2085 tid_agg_rx->reorder_buf[index],
2086 &status, rate);
2087 tid_agg_rx->stored_mpdu_num--;
2088 tid_agg_rx->reorder_buf[index] = NULL;
2089 }
2090 tid_agg_rx->head_seq_num =
2091 seq_inc(tid_agg_rx->head_seq_num);
2092 }
2093 if (bar_req)
2094 return 1;
2095 }
2096
2097 /* now the new frame is always in the range of the reordering */
2098 /* buffer window */
2099 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2100 % tid_agg_rx->buf_size;
2101 /* check if we already stored this frame */
2102 if (tid_agg_rx->reorder_buf[index]) {
2103 dev_kfree_skb(skb);
2104 return 1;
2105 }
2106
2107 /* if arrived mpdu is in the right order and nothing else stored */
2108 /* release it immediately */
2109 if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2110 tid_agg_rx->stored_mpdu_num == 0) {
2111 tid_agg_rx->head_seq_num =
2112 seq_inc(tid_agg_rx->head_seq_num);
2113 return 0;
2114 }
2115
2116 /* put the frame in the reordering buffer */
2117 tid_agg_rx->reorder_buf[index] = skb;
2118 tid_agg_rx->stored_mpdu_num++;
2119 /* release the buffer until next missing frame */
2120 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2121 % tid_agg_rx->buf_size;
2122 while (tid_agg_rx->reorder_buf[index]) {
2123 /* release the reordered frame back to stack */
2124 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2125 sizeof(status));
2126 sband = local->hw.wiphy->bands[status.band];
2127 if (status.flag & RX_FLAG_HT)
2128 rate = sband->bitrates; /* TODO: HT rates */
2129 else
2130 rate = &sband->bitrates[status.rate_idx];
2131 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2132 &status, rate);
2133 tid_agg_rx->stored_mpdu_num--;
2134 tid_agg_rx->reorder_buf[index] = NULL;
2135 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2136 index = seq_sub(tid_agg_rx->head_seq_num,
2137 tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2138 }
2139 return 1;
2140 }
2141
ieee80211_rx_reorder_ampdu(struct ieee80211_local * local,struct sk_buff * skb)2142 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2143 struct sk_buff *skb)
2144 {
2145 struct ieee80211_hw *hw = &local->hw;
2146 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2147 struct sta_info *sta;
2148 struct tid_ampdu_rx *tid_agg_rx;
2149 u16 sc;
2150 u16 mpdu_seq_num;
2151 u8 ret = 0;
2152 int tid;
2153
2154 sta = sta_info_get(local, hdr->addr2);
2155 if (!sta)
2156 return ret;
2157
2158 /* filter the QoS data rx stream according to
2159 * STA/TID and check if this STA/TID is on aggregation */
2160 if (!ieee80211_is_data_qos(hdr->frame_control))
2161 goto end_reorder;
2162
2163 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2164
2165 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2166 goto end_reorder;
2167
2168 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2169
2170 /* qos null data frames are excluded */
2171 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2172 goto end_reorder;
2173
2174 /* new un-ordered ampdu frame - process it */
2175
2176 /* reset session timer */
2177 if (tid_agg_rx->timeout) {
2178 unsigned long expires =
2179 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2180 mod_timer(&tid_agg_rx->session_timer, expires);
2181 }
2182
2183 /* if this mpdu is fragmented - terminate rx aggregation session */
2184 sc = le16_to_cpu(hdr->seq_ctrl);
2185 if (sc & IEEE80211_SCTL_FRAG) {
2186 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2187 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2188 ret = 1;
2189 goto end_reorder;
2190 }
2191
2192 /* according to mpdu sequence number deal with reordering buffer */
2193 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2194 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2195 mpdu_seq_num, 0);
2196 end_reorder:
2197 return ret;
2198 }
2199
2200 /*
2201 * This is the receive path handler. It is called by a low level driver when an
2202 * 802.11 MPDU is received from the hardware.
2203 */
__ieee80211_rx(struct ieee80211_hw * hw,struct sk_buff * skb,struct ieee80211_rx_status * status)2204 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2205 struct ieee80211_rx_status *status)
2206 {
2207 struct ieee80211_local *local = hw_to_local(hw);
2208 struct ieee80211_rate *rate = NULL;
2209 struct ieee80211_supported_band *sband;
2210
2211 if (status->band < 0 ||
2212 status->band >= IEEE80211_NUM_BANDS) {
2213 WARN_ON(1);
2214 return;
2215 }
2216
2217 sband = local->hw.wiphy->bands[status->band];
2218 if (!sband) {
2219 WARN_ON(1);
2220 return;
2221 }
2222
2223 if (status->flag & RX_FLAG_HT) {
2224 /* rate_idx is MCS index */
2225 if (WARN_ON(status->rate_idx < 0 ||
2226 status->rate_idx >= 76))
2227 return;
2228 /* HT rates are not in the table - use the highest legacy rate
2229 * for now since other parts of mac80211 may not yet be fully
2230 * MCS aware. */
2231 rate = &sband->bitrates[sband->n_bitrates - 1];
2232 } else {
2233 if (WARN_ON(status->rate_idx < 0 ||
2234 status->rate_idx >= sband->n_bitrates))
2235 return;
2236 rate = &sband->bitrates[status->rate_idx];
2237 }
2238
2239 /*
2240 * key references and virtual interfaces are protected using RCU
2241 * and this requires that we are in a read-side RCU section during
2242 * receive processing
2243 */
2244 rcu_read_lock();
2245
2246 /*
2247 * Frames with failed FCS/PLCP checksum are not returned,
2248 * all other frames are returned without radiotap header
2249 * if it was previously present.
2250 * Also, frames with less than 16 bytes are dropped.
2251 */
2252 skb = ieee80211_rx_monitor(local, skb, status, rate);
2253 if (!skb) {
2254 rcu_read_unlock();
2255 return;
2256 }
2257
2258 if (!ieee80211_rx_reorder_ampdu(local, skb))
2259 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2260
2261 rcu_read_unlock();
2262 }
2263 EXPORT_SYMBOL(__ieee80211_rx);
2264
2265 /* This is a version of the rx handler that can be called from hard irq
2266 * context. Post the skb on the queue and schedule the tasklet */
ieee80211_rx_irqsafe(struct ieee80211_hw * hw,struct sk_buff * skb,struct ieee80211_rx_status * status)2267 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2268 struct ieee80211_rx_status *status)
2269 {
2270 struct ieee80211_local *local = hw_to_local(hw);
2271
2272 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2273
2274 skb->dev = local->mdev;
2275 /* copy status into skb->cb for use by tasklet */
2276 memcpy(skb->cb, status, sizeof(*status));
2277 skb->pkt_type = IEEE80211_RX_MSG;
2278 skb_queue_tail(&local->skb_queue, skb);
2279 tasklet_schedule(&local->tasklet);
2280 }
2281 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
2282