projects / deliverable / linux.git / blob
? search:


a0dfafb4f38beb430317312d39db8d8774509863
[deliverable/linux.git] / net / mac80211 / rx.c
1 /*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/skbuff.h>
14 #include <linux/netdevice.h>
15 #include <linux/etherdevice.h>
16 #include <linux/rcupdate.h>
17 #include <net/mac80211.h>
18 #include <net/ieee80211_radiotap.h>
19
20 #include "ieee80211_i.h"
21 #include "ieee80211_led.h"
22 #include "ieee80211_common.h"
23 #include "wep.h"
24 #include "wpa.h"
25 #include "tkip.h"
26 #include "wme.h"
27
28 /*
29 * monitor mode reception
30 *
31 * This function cleans up the SKB, i.e. it removes all the stuff
32 * only useful for monitoring.
33 */
34 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
35 struct sk_buff *skb,
36 int rtap_len)
37 {
38 skb_pull(skb, rtap_len);
39
40 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
41 if (likely(skb->len > FCS_LEN))
42 skb_trim(skb, skb->len - FCS_LEN);
43 else {
44 /* driver bug */
45 WARN_ON(1);
46 dev_kfree_skb(skb);
47 skb = NULL;
48 }
49 }
50
51 return skb;
52 }
53
54 static inline int should_drop_frame(struct ieee80211_rx_status *status,
55 struct sk_buff *skb,
56 int present_fcs_len,
57 int radiotap_len)
58 {
59 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
60
61 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
62 return 1;
63 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
64 return 1;
65 if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
66 cpu_to_le16(IEEE80211_FTYPE_CTL))
67 return 1;
68 return 0;
69 }
70
71 /*
72 * This function copies a received frame to all monitor interfaces and
73 * returns a cleaned-up SKB that no longer includes the FCS nor the
74 * radiotap header the driver might have added.
75 */
76 static struct sk_buff *
77 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
78 struct ieee80211_rx_status *status)
79 {
80 struct ieee80211_sub_if_data *sdata;
81 struct ieee80211_rate *rate;
82 int needed_headroom = 0;
83 struct ieee80211_rtap_hdr {
84 struct ieee80211_radiotap_header hdr;
85 u8 flags;
86 u8 rate;
87 __le16 chan_freq;
88 __le16 chan_flags;
89 u8 antsignal;
90 u8 padding_for_rxflags;
91 __le16 rx_flags;
92 } __attribute__ ((packed)) *rthdr;
93 struct sk_buff *skb, *skb2;
94 struct net_device *prev_dev = NULL;
95 int present_fcs_len = 0;
96 int rtap_len = 0;
97
98 /*
99 * First, we may need to make a copy of the skb because
100 * (1) we need to modify it for radiotap (if not present), and
101 * (2) the other RX handlers will modify the skb we got.
102 *
103 * We don't need to, of course, if we aren't going to return
104 * the SKB because it has a bad FCS/PLCP checksum.
105 */
106 if (status->flag & RX_FLAG_RADIOTAP)
107 rtap_len = ieee80211_get_radiotap_len(origskb->data);
108 else
109 needed_headroom = sizeof(*rthdr);
110
111 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
112 present_fcs_len = FCS_LEN;
113
114 if (!local->monitors) {
115 if (should_drop_frame(status, origskb, present_fcs_len,
116 rtap_len)) {
117 dev_kfree_skb(origskb);
118 return NULL;
119 }
120
121 return remove_monitor_info(local, origskb, rtap_len);
122 }
123
124 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
125 /* only need to expand headroom if necessary */
126 skb = origskb;
127 origskb = NULL;
128
129 /*
130 * This shouldn't trigger often because most devices have an
131 * RX header they pull before we get here, and that should
132 * be big enough for our radiotap information. We should
133 * probably export the length to drivers so that we can have
134 * them allocate enough headroom to start with.
135 */
136 if (skb_headroom(skb) < needed_headroom &&
137 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) {
138 dev_kfree_skb(skb);
139 return NULL;
140 }
141 } else {
142 /*
143 * Need to make a copy and possibly remove radiotap header
144 * and FCS from the original.
145 */
146 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
147
148 origskb = remove_monitor_info(local, origskb, rtap_len);
149
150 if (!skb)
151 return origskb;
152 }
153
154 /* if necessary, prepend radiotap information */
155 if (!(status->flag & RX_FLAG_RADIOTAP)) {
156 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
157 memset(rthdr, 0, sizeof(*rthdr));
158 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
159 rthdr->hdr.it_present =
160 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
161 (1 << IEEE80211_RADIOTAP_RATE) |
162 (1 << IEEE80211_RADIOTAP_CHANNEL) |
163 (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
164 (1 << IEEE80211_RADIOTAP_RX_FLAGS));
165 rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ?
166 IEEE80211_RADIOTAP_F_FCS : 0;
167
168 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
169 rthdr->rx_flags = 0;
170 if (status->flag &
171 (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
172 rthdr->rx_flags |=
173 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
174
175 rate = ieee80211_get_rate(local, status->phymode,
176 status->rate);
177 if (rate)
178 rthdr->rate = rate->rate / 5;
179
180 rthdr->chan_freq = cpu_to_le16(status->freq);
181
182 if (status->phymode == MODE_IEEE80211A)
183 rthdr->chan_flags =
184 cpu_to_le16(IEEE80211_CHAN_OFDM |
185 IEEE80211_CHAN_5GHZ);
186 else
187 rthdr->chan_flags =
188 cpu_to_le16(IEEE80211_CHAN_DYN |
189 IEEE80211_CHAN_2GHZ);
190
191 rthdr->antsignal = status->ssi;
192 }
193
194 skb_set_mac_header(skb, 0);
195 skb->ip_summed = CHECKSUM_UNNECESSARY;
196 skb->pkt_type = PACKET_OTHERHOST;
197 skb->protocol = htons(ETH_P_802_2);
198
199 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
200 if (!netif_running(sdata->dev))
201 continue;
202
203 if (sdata->type != IEEE80211_IF_TYPE_MNTR)
204 continue;
205
206 if (prev_dev) {
207 skb2 = skb_clone(skb, GFP_ATOMIC);
208 if (skb2) {
209 skb2->dev = prev_dev;
210 netif_rx(skb2);
211 }
212 }
213
214 prev_dev = sdata->dev;
215 sdata->dev->stats.rx_packets++;
216 sdata->dev->stats.rx_bytes += skb->len;
217 }
218
219 if (prev_dev) {
220 skb->dev = prev_dev;
221 netif_rx(skb);
222 } else
223 dev_kfree_skb(skb);
224
225 return origskb;
226 }
227
228
229 /* pre-rx handlers
230 *
231 * these don't have dev/sdata fields in the rx data
232 * The sta value should also not be used because it may
233 * be NULL even though a STA (in IBSS mode) will be added.
234 */
235
236 static ieee80211_txrx_result
237 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
238 {
239 u8 *data = rx->skb->data;
240 int tid;
241
242 /* does the frame have a qos control field? */
243 if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
244 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
245 /* frame has qos control */
246 tid = qc[0] & QOS_CONTROL_TID_MASK;
247 } else {
248 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
249 /* Separate TID for management frames */
250 tid = NUM_RX_DATA_QUEUES - 1;
251 } else {
252 /* no qos control present */
253 tid = 0; /* 802.1d - Best Effort */
254 }
255 }
256
257 I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
258 /* only a debug counter, sta might not be assigned properly yet */
259 if (rx->sta)
260 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
261
262 rx->u.rx.queue = tid;
263 /* Set skb->priority to 1d tag if highest order bit of TID is not set.
264 * For now, set skb->priority to 0 for other cases. */
265 rx->skb->priority = (tid > 7) ? 0 : tid;
266
267 return TXRX_CONTINUE;
268 }
269
270 static ieee80211_txrx_result
271 ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx)
272 {
273 struct ieee80211_local *local = rx->local;
274 struct sk_buff *skb = rx->skb;
275 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
276 u32 load = 0, hdrtime;
277 struct ieee80211_rate *rate;
278 struct ieee80211_hw_mode *mode = local->hw.conf.mode;
279 int i;
280
281 /* Estimate total channel use caused by this frame */
282
283 if (unlikely(mode->num_rates < 0))
284 return TXRX_CONTINUE;
285
286 rate = &mode->rates[0];
287 for (i = 0; i < mode->num_rates; i++) {
288 if (mode->rates[i].val == rx->u.rx.status->rate) {
289 rate = &mode->rates[i];
290 break;
291 }
292 }
293
294 /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
295 * 1 usec = 1/8 * (1080 / 10) = 13.5 */
296
297 if (mode->mode == MODE_IEEE80211A ||
298 (mode->mode == MODE_IEEE80211G &&
299 rate->flags & IEEE80211_RATE_ERP))
300 hdrtime = CHAN_UTIL_HDR_SHORT;
301 else
302 hdrtime = CHAN_UTIL_HDR_LONG;
303
304 load = hdrtime;
305 if (!is_multicast_ether_addr(hdr->addr1))
306 load += hdrtime;
307
308 load += skb->len * rate->rate_inv;
309
310 /* Divide channel_use by 8 to avoid wrapping around the counter */
311 load >>= CHAN_UTIL_SHIFT;
312 local->channel_use_raw += load;
313 rx->u.rx.load = load;
314
315 return TXRX_CONTINUE;
316 }
317
318 ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
319 {
320 ieee80211_rx_h_parse_qos,
321 ieee80211_rx_h_load_stats,
322 NULL
323 };
324
325 /* rx handlers */
326
327 static ieee80211_txrx_result
328 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
329 {
330 if (rx->sta)
331 rx->sta->channel_use_raw += rx->u.rx.load;
332 rx->sdata->channel_use_raw += rx->u.rx.load;
333 return TXRX_CONTINUE;
334 }
335
336 static ieee80211_txrx_result
337 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
338 {
339 struct ieee80211_local *local = rx->local;
340 struct sk_buff *skb = rx->skb;
341
342 if (unlikely(local->sta_scanning != 0)) {
343 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
344 return TXRX_QUEUED;
345 }
346
347 if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
348 /* scanning finished during invoking of handlers */
349 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
350 return TXRX_DROP;
351 }
352
353 return TXRX_CONTINUE;
354 }
355
356 static ieee80211_txrx_result
357 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
358 {
359 struct ieee80211_hdr *hdr;
360 hdr = (struct ieee80211_hdr *) rx->skb->data;
361
362 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
363 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
364 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
365 rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
366 hdr->seq_ctrl)) {
367 if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
368 rx->local->dot11FrameDuplicateCount++;
369 rx->sta->num_duplicates++;
370 }
371 return TXRX_DROP;
372 } else
373 rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
374 }
375
376 if (unlikely(rx->skb->len < 16)) {
377 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
378 return TXRX_DROP;
379 }
380
381 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
382 rx->skb->pkt_type = PACKET_OTHERHOST;
383 else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
384 rx->skb->pkt_type = PACKET_HOST;
385 else if (is_multicast_ether_addr(hdr->addr1)) {
386 if (is_broadcast_ether_addr(hdr->addr1))
387 rx->skb->pkt_type = PACKET_BROADCAST;
388 else
389 rx->skb->pkt_type = PACKET_MULTICAST;
390 } else
391 rx->skb->pkt_type = PACKET_OTHERHOST;
392
393 /* Drop disallowed frame classes based on STA auth/assoc state;
394 * IEEE 802.11, Chap 5.5.
395 *
396 * 80211.o does filtering only based on association state, i.e., it
397 * drops Class 3 frames from not associated stations. hostapd sends
398 * deauth/disassoc frames when needed. In addition, hostapd is
399 * responsible for filtering on both auth and assoc states.
400 */
401 if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
402 ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
403 (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
404 rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
405 (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
406 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
407 !(rx->fc & IEEE80211_FCTL_TODS) &&
408 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
409 || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
410 /* Drop IBSS frames and frames for other hosts
411 * silently. */
412 return TXRX_DROP;
413 }
414
415 if (!rx->local->apdev)
416 return TXRX_DROP;
417
418 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
419 ieee80211_msg_sta_not_assoc);
420 return TXRX_QUEUED;
421 }
422
423 return TXRX_CONTINUE;
424 }
425
426
427 static ieee80211_txrx_result
428 ieee80211_rx_h_load_key(struct ieee80211_txrx_data *rx)
429 {
430 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
431 int keyidx;
432 int hdrlen;
433 struct ieee80211_key *stakey = NULL;
434
435 /*
436 * Key selection 101
437 *
438 * There are three types of keys:
439 * - GTK (group keys)
440 * - PTK (pairwise keys)
441 * - STK (station-to-station pairwise keys)
442 *
443 * When selecting a key, we have to distinguish between multicast
444 * (including broadcast) and unicast frames, the latter can only
445 * use PTKs and STKs while the former always use GTKs. Unless, of
446 * course, actual WEP keys ("pre-RSNA") are used, then unicast
447 * frames can also use key indizes like GTKs. Hence, if we don't
448 * have a PTK/STK we check the key index for a WEP key.
449 *
450 * Note that in a regular BSS, multicast frames are sent by the
451 * AP only, associated stations unicast the frame to the AP first
452 * which then multicasts it on their behalf.
453 *
454 * There is also a slight problem in IBSS mode: GTKs are negotiated
455 * with each station, that is something we don't currently handle.
456 * The spec seems to expect that one negotiates the same key with
457 * every station but there's no such requirement; VLANs could be
458 * possible.
459 */
460
461 if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
462 return TXRX_CONTINUE;
463
464 /*
465 * No point in finding a key if the frame is neither
466 * addressed to us nor a multicast frame.
467 */
468 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
469 return TXRX_CONTINUE;
470
471 if (rx->sta)
472 stakey = rcu_dereference(rx->sta->key);
473
474 if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
475 rx->key = stakey;
476 } else {
477 /*
478 * The device doesn't give us the IV so we won't be
479 * able to look up the key. That's ok though, we
480 * don't need to decrypt the frame, we just won't
481 * be able to keep statistics accurate.
482 * Except for key threshold notifications, should
483 * we somehow allow the driver to tell us which key
484 * the hardware used if this flag is set?
485 */
486 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
487 (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
488 return TXRX_CONTINUE;
489
490 hdrlen = ieee80211_get_hdrlen(rx->fc);
491
492 if (rx->skb->len < 8 + hdrlen)
493 return TXRX_DROP; /* TODO: count this? */
494
495 /*
496 * no need to call ieee80211_wep_get_keyidx,
497 * it verifies a bunch of things we've done already
498 */
499 keyidx = rx->skb->data[hdrlen + 3] >> 6;
500
501 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
502
503 /*
504 * RSNA-protected unicast frames should always be sent with
505 * pairwise or station-to-station keys, but for WEP we allow
506 * using a key index as well.
507 */
508 if (rx->key && rx->key->conf.alg != ALG_WEP &&
509 !is_multicast_ether_addr(hdr->addr1))
510 rx->key = NULL;
511 }
512
513 if (rx->key) {
514 rx->key->tx_rx_count++;
515 /* TODO: add threshold stuff again */
516 }
517
518 return TXRX_CONTINUE;
519 }
520
521 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
522 {
523 struct ieee80211_sub_if_data *sdata;
524 DECLARE_MAC_BUF(mac);
525
526 sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
527
528 if (sdata->bss)
529 atomic_inc(&sdata->bss->num_sta_ps);
530 sta->flags |= WLAN_STA_PS;
531 sta->pspoll = 0;
532 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
533 printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
534 dev->name, print_mac(mac, sta->addr), sta->aid);
535 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
536 }
537
538 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
539 {
540 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
541 struct sk_buff *skb;
542 int sent = 0;
543 struct ieee80211_sub_if_data *sdata;
544 struct ieee80211_tx_packet_data *pkt_data;
545 DECLARE_MAC_BUF(mac);
546
547 sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
548 if (sdata->bss)
549 atomic_dec(&sdata->bss->num_sta_ps);
550 sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
551 sta->pspoll = 0;
552 if (!skb_queue_empty(&sta->ps_tx_buf)) {
553 if (local->ops->set_tim)
554 local->ops->set_tim(local_to_hw(local), sta->aid, 0);
555 if (sdata->bss)
556 bss_tim_clear(local, sdata->bss, sta->aid);
557 }
558 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
559 printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
560 dev->name, print_mac(mac, sta->addr), sta->aid);
561 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
562 /* Send all buffered frames to the station */
563 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
564 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
565 sent++;
566 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
567 dev_queue_xmit(skb);
568 }
569 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
570 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
571 local->total_ps_buffered--;
572 sent++;
573 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
574 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
575 "since STA not sleeping anymore\n", dev->name,
576 print_mac(mac, sta->addr), sta->aid);
577 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
578 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
579 dev_queue_xmit(skb);
580 }
581
582 return sent;
583 }
584
585 static ieee80211_txrx_result
586 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
587 {
588 struct sta_info *sta = rx->sta;
589 struct net_device *dev = rx->dev;
590 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
591
592 if (!sta)
593 return TXRX_CONTINUE;
594
595 /* Update last_rx only for IBSS packets which are for the current
596 * BSSID to avoid keeping the current IBSS network alive in cases where
597 * other STAs are using different BSSID. */
598 if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
599 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
600 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
601 sta->last_rx = jiffies;
602 } else
603 if (!is_multicast_ether_addr(hdr->addr1) ||
604 rx->sdata->type == IEEE80211_IF_TYPE_STA) {
605 /* Update last_rx only for unicast frames in order to prevent
606 * the Probe Request frames (the only broadcast frames from a
607 * STA in infrastructure mode) from keeping a connection alive.
608 */
609 sta->last_rx = jiffies;
610 }
611
612 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
613 return TXRX_CONTINUE;
614
615 sta->rx_fragments++;
616 sta->rx_bytes += rx->skb->len;
617 sta->last_rssi = rx->u.rx.status->ssi;
618 sta->last_signal = rx->u.rx.status->signal;
619 sta->last_noise = rx->u.rx.status->noise;
620
621 if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
622 /* Change STA power saving mode only in the end of a frame
623 * exchange sequence */
624 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
625 rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
626 else if (!(sta->flags & WLAN_STA_PS) &&
627 (rx->fc & IEEE80211_FCTL_PM))
628 ap_sta_ps_start(dev, sta);
629 }
630
631 /* Drop data::nullfunc frames silently, since they are used only to
632 * control station power saving mode. */
633 if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
634 (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
635 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
636 /* Update counter and free packet here to avoid counting this
637 * as a dropped packed. */
638 sta->rx_packets++;
639 dev_kfree_skb(rx->skb);
640 return TXRX_QUEUED;
641 }
642
643 return TXRX_CONTINUE;
644 } /* ieee80211_rx_h_sta_process */
645
646 static ieee80211_txrx_result
647 ieee80211_rx_h_wep_weak_iv_detection(struct ieee80211_txrx_data *rx)
648 {
649 if (!rx->sta || !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
650 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
651 !rx->key || rx->key->conf.alg != ALG_WEP ||
652 !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
653 return TXRX_CONTINUE;
654
655 /* Check for weak IVs, if hwaccel did not remove IV from the frame */
656 if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
657 !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED))
658 if (ieee80211_wep_is_weak_iv(rx->skb, rx->key))
659 rx->sta->wep_weak_iv_count++;
660
661 return TXRX_CONTINUE;
662 }
663
664 static ieee80211_txrx_result
665 ieee80211_rx_h_wep_decrypt(struct ieee80211_txrx_data *rx)
666 {
667 if ((rx->key && rx->key->conf.alg != ALG_WEP) ||
668 !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
669 ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
670 ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
671 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
672 return TXRX_CONTINUE;
673
674 if (!rx->key) {
675 if (net_ratelimit())
676 printk(KERN_DEBUG "%s: RX WEP frame, but no key set\n",
677 rx->dev->name);
678 return TXRX_DROP;
679 }
680
681 if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
682 if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
683 if (net_ratelimit())
684 printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
685 "failed\n", rx->dev->name);
686 return TXRX_DROP;
687 }
688 } else if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) {
689 ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
690 /* remove ICV */
691 skb_trim(rx->skb, rx->skb->len - 4);
692 }
693
694 return TXRX_CONTINUE;
695 }
696
697 static inline struct ieee80211_fragment_entry *
698 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
699 unsigned int frag, unsigned int seq, int rx_queue,
700 struct sk_buff **skb)
701 {
702 struct ieee80211_fragment_entry *entry;
703 int idx;
704
705 idx = sdata->fragment_next;
706 entry = &sdata->fragments[sdata->fragment_next++];
707 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
708 sdata->fragment_next = 0;
709
710 if (!skb_queue_empty(&entry->skb_list)) {
711 #ifdef CONFIG_MAC80211_DEBUG
712 struct ieee80211_hdr *hdr =
713 (struct ieee80211_hdr *) entry->skb_list.next->data;
714 DECLARE_MAC_BUF(mac);
715 DECLARE_MAC_BUF(mac2);
716 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
717 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
718 "addr1=%s addr2=%s\n",
719 sdata->dev->name, idx,
720 jiffies - entry->first_frag_time, entry->seq,
721 entry->last_frag, print_mac(mac, hdr->addr1),
722 print_mac(mac2, hdr->addr2));
723 #endif /* CONFIG_MAC80211_DEBUG */
724 __skb_queue_purge(&entry->skb_list);
725 }
726
727 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
728 *skb = NULL;
729 entry->first_frag_time = jiffies;
730 entry->seq = seq;
731 entry->rx_queue = rx_queue;
732 entry->last_frag = frag;
733 entry->ccmp = 0;
734 entry->extra_len = 0;
735
736 return entry;
737 }
738
739 static inline struct ieee80211_fragment_entry *
740 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
741 u16 fc, unsigned int frag, unsigned int seq,
742 int rx_queue, struct ieee80211_hdr *hdr)
743 {
744 struct ieee80211_fragment_entry *entry;
745 int i, idx;
746
747 idx = sdata->fragment_next;
748 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
749 struct ieee80211_hdr *f_hdr;
750 u16 f_fc;
751
752 idx--;
753 if (idx < 0)
754 idx = IEEE80211_FRAGMENT_MAX - 1;
755
756 entry = &sdata->fragments[idx];
757 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
758 entry->rx_queue != rx_queue ||
759 entry->last_frag + 1 != frag)
760 continue;
761
762 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
763 f_fc = le16_to_cpu(f_hdr->frame_control);
764
765 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
766 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
767 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
768 continue;
769
770 if (entry->first_frag_time + 2 * HZ < jiffies) {
771 __skb_queue_purge(&entry->skb_list);
772 continue;
773 }
774 return entry;
775 }
776
777 return NULL;
778 }
779
780 static ieee80211_txrx_result
781 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
782 {
783 struct ieee80211_hdr *hdr;
784 u16 sc;
785 unsigned int frag, seq;
786 struct ieee80211_fragment_entry *entry;
787 struct sk_buff *skb;
788 DECLARE_MAC_BUF(mac);
789
790 hdr = (struct ieee80211_hdr *) rx->skb->data;
791 sc = le16_to_cpu(hdr->seq_ctrl);
792 frag = sc & IEEE80211_SCTL_FRAG;
793
794 if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
795 (rx->skb)->len < 24 ||
796 is_multicast_ether_addr(hdr->addr1))) {
797 /* not fragmented */
798 goto out;
799 }
800 I802_DEBUG_INC(rx->local->rx_handlers_fragments);
801
802 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
803
804 if (frag == 0) {
805 /* This is the first fragment of a new frame. */
806 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
807 rx->u.rx.queue, &(rx->skb));
808 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
809 (rx->fc & IEEE80211_FCTL_PROTECTED)) {
810 /* Store CCMP PN so that we can verify that the next
811 * fragment has a sequential PN value. */
812 entry->ccmp = 1;
813 memcpy(entry->last_pn,
814 rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
815 CCMP_PN_LEN);
816 }
817 return TXRX_QUEUED;
818 }
819
820 /* This is a fragment for a frame that should already be pending in
821 * fragment cache. Add this fragment to the end of the pending entry.
822 */
823 entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
824 rx->u.rx.queue, hdr);
825 if (!entry) {
826 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
827 return TXRX_DROP;
828 }
829
830 /* Verify that MPDUs within one MSDU have sequential PN values.
831 * (IEEE 802.11i, 8.3.3.4.5) */
832 if (entry->ccmp) {
833 int i;
834 u8 pn[CCMP_PN_LEN], *rpn;
835 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
836 return TXRX_DROP;
837 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
838 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
839 pn[i]++;
840 if (pn[i])
841 break;
842 }
843 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
844 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
845 if (net_ratelimit())
846 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
847 "sequential A2=%s"
848 " PN=%02x%02x%02x%02x%02x%02x "
849 "(expected %02x%02x%02x%02x%02x%02x)\n",
850 rx->dev->name, print_mac(mac, hdr->addr2),
851 rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
852 rpn[5], pn[0], pn[1], pn[2], pn[3],
853 pn[4], pn[5]);
854 return TXRX_DROP;
855 }
856 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
857 }
858
859 skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
860 __skb_queue_tail(&entry->skb_list, rx->skb);
861 entry->last_frag = frag;
862 entry->extra_len += rx->skb->len;
863 if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
864 rx->skb = NULL;
865 return TXRX_QUEUED;
866 }
867
868 rx->skb = __skb_dequeue(&entry->skb_list);
869 if (skb_tailroom(rx->skb) < entry->extra_len) {
870 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
871 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
872 GFP_ATOMIC))) {
873 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
874 __skb_queue_purge(&entry->skb_list);
875 return TXRX_DROP;
876 }
877 }
878 while ((skb = __skb_dequeue(&entry->skb_list))) {
879 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
880 dev_kfree_skb(skb);
881 }
882
883 /* Complete frame has been reassembled - process it now */
884 rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
885
886 out:
887 if (rx->sta)
888 rx->sta->rx_packets++;
889 if (is_multicast_ether_addr(hdr->addr1))
890 rx->local->dot11MulticastReceivedFrameCount++;
891 else
892 ieee80211_led_rx(rx->local);
893 return TXRX_CONTINUE;
894 }
895
896 static ieee80211_txrx_result
897 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
898 {
899 struct sk_buff *skb;
900 int no_pending_pkts;
901 DECLARE_MAC_BUF(mac);
902
903 if (likely(!rx->sta ||
904 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
905 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
906 !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
907 return TXRX_CONTINUE;
908
909 skb = skb_dequeue(&rx->sta->tx_filtered);
910 if (!skb) {
911 skb = skb_dequeue(&rx->sta->ps_tx_buf);
912 if (skb)
913 rx->local->total_ps_buffered--;
914 }
915 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
916 skb_queue_empty(&rx->sta->ps_tx_buf);
917
918 if (skb) {
919 struct ieee80211_hdr *hdr =
920 (struct ieee80211_hdr *) skb->data;
921
922 /* tell TX path to send one frame even though the STA may
923 * still remain is PS mode after this frame exchange */
924 rx->sta->pspoll = 1;
925
926 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
927 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
928 print_mac(mac, rx->sta->addr), rx->sta->aid,
929 skb_queue_len(&rx->sta->ps_tx_buf));
930 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
931
932 /* Use MoreData flag to indicate whether there are more
933 * buffered frames for this STA */
934 if (no_pending_pkts) {
935 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
936 rx->sta->flags &= ~WLAN_STA_TIM;
937 } else
938 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
939
940 dev_queue_xmit(skb);
941
942 if (no_pending_pkts) {
943 if (rx->local->ops->set_tim)
944 rx->local->ops->set_tim(local_to_hw(rx->local),
945 rx->sta->aid, 0);
946 if (rx->sdata->bss)
947 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
948 }
949 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
950 } else if (!rx->u.rx.sent_ps_buffered) {
951 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
952 "though there is no buffered frames for it\n",
953 rx->dev->name, print_mac(mac, rx->sta->addr));
954 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
955
956 }
957
958 /* Free PS Poll skb here instead of returning TXRX_DROP that would
959 * count as an dropped frame. */
960 dev_kfree_skb(rx->skb);
961
962 return TXRX_QUEUED;
963 }
964
965 static ieee80211_txrx_result
966 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
967 {
968 u16 fc = rx->fc;
969 u8 *data = rx->skb->data;
970 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
971
972 if (!WLAN_FC_IS_QOS_DATA(fc))
973 return TXRX_CONTINUE;
974
975 /* remove the qos control field, update frame type and meta-data */
976 memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
977 hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
978 /* change frame type to non QOS */
979 rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
980 hdr->frame_control = cpu_to_le16(fc);
981
982 return TXRX_CONTINUE;
983 }
984
985 static ieee80211_txrx_result
986 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
987 {
988 if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
989 rx->sdata->type != IEEE80211_IF_TYPE_STA &&
990 (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
991 /* Pass both encrypted and unencrypted EAPOL frames to user
992 * space for processing. */
993 if (!rx->local->apdev)
994 return TXRX_DROP;
995 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
996 ieee80211_msg_normal);
997 return TXRX_QUEUED;
998 }
999
1000 if (unlikely(rx->sdata->ieee802_1x &&
1001 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1002 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1003 (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
1004 !ieee80211_is_eapol(rx->skb))) {
1005 #ifdef CONFIG_MAC80211_DEBUG
1006 struct ieee80211_hdr *hdr =
1007 (struct ieee80211_hdr *) rx->skb->data;
1008 DECLARE_MAC_BUF(mac);
1009 printk(KERN_DEBUG "%s: dropped frame from %s"
1010 " (unauthorized port)\n", rx->dev->name,
1011 print_mac(mac, hdr->addr2));
1012 #endif /* CONFIG_MAC80211_DEBUG */
1013 return TXRX_DROP;
1014 }
1015
1016 return TXRX_CONTINUE;
1017 }
1018
1019 static ieee80211_txrx_result
1020 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
1021 {
1022 /*
1023 * Pass through unencrypted frames if the hardware has
1024 * decrypted them already.
1025 */
1026 if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1027 return TXRX_CONTINUE;
1028
1029 /* Drop unencrypted frames if key is set. */
1030 if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1031 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1032 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1033 (rx->key || rx->sdata->drop_unencrypted) &&
1034 (rx->sdata->eapol == 0 ||
1035 !ieee80211_is_eapol(rx->skb)))) {
1036 if (net_ratelimit())
1037 printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1038 "encryption\n", rx->dev->name);
1039 return TXRX_DROP;
1040 }
1041 return TXRX_CONTINUE;
1042 }
1043
1044 static ieee80211_txrx_result
1045 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1046 {
1047 struct net_device *dev = rx->dev;
1048 struct ieee80211_local *local = rx->local;
1049 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1050 u16 fc, hdrlen, ethertype;
1051 u8 *payload;
1052 u8 dst[ETH_ALEN];
1053 u8 src[ETH_ALEN];
1054 struct sk_buff *skb = rx->skb, *skb2;
1055 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1056 DECLARE_MAC_BUF(mac);
1057 DECLARE_MAC_BUF(mac2);
1058 DECLARE_MAC_BUF(mac3);
1059 DECLARE_MAC_BUF(mac4);
1060
1061 fc = rx->fc;
1062 if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1063 return TXRX_CONTINUE;
1064
1065 if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1066 return TXRX_DROP;
1067
1068 hdrlen = ieee80211_get_hdrlen(fc);
1069
1070 /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1071 * header
1072 * IEEE 802.11 address fields:
1073 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1074 * 0 0 DA SA BSSID n/a
1075 * 0 1 DA BSSID SA n/a
1076 * 1 0 BSSID SA DA n/a
1077 * 1 1 RA TA DA SA
1078 */
1079
1080 switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1081 case IEEE80211_FCTL_TODS:
1082 /* BSSID SA DA */
1083 memcpy(dst, hdr->addr3, ETH_ALEN);
1084 memcpy(src, hdr->addr2, ETH_ALEN);
1085
1086 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
1087 sdata->type != IEEE80211_IF_TYPE_VLAN)) {
1088 if (net_ratelimit())
1089 printk(KERN_DEBUG "%s: dropped ToDS frame "
1090 "(BSSID=%s SA=%s DA=%s)\n",
1091 dev->name,
1092 print_mac(mac, hdr->addr1),
1093 print_mac(mac2, hdr->addr2),
1094 print_mac(mac3, hdr->addr3));
1095 return TXRX_DROP;
1096 }
1097 break;
1098 case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1099 /* RA TA DA SA */
1100 memcpy(dst, hdr->addr3, ETH_ALEN);
1101 memcpy(src, hdr->addr4, ETH_ALEN);
1102
1103 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
1104 if (net_ratelimit())
1105 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1106 "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1107 rx->dev->name,
1108 print_mac(mac, hdr->addr1),
1109 print_mac(mac2, hdr->addr2),
1110 print_mac(mac3, hdr->addr3),
1111 print_mac(mac4, hdr->addr4));
1112 return TXRX_DROP;
1113 }
1114 break;
1115 case IEEE80211_FCTL_FROMDS:
1116 /* DA BSSID SA */
1117 memcpy(dst, hdr->addr1, ETH_ALEN);
1118 memcpy(src, hdr->addr3, ETH_ALEN);
1119
1120 if (sdata->type != IEEE80211_IF_TYPE_STA ||
1121 (is_multicast_ether_addr(dst) &&
1122 !compare_ether_addr(src, dev->dev_addr)))
1123 return TXRX_DROP;
1124 break;
1125 case 0:
1126 /* DA SA BSSID */
1127 memcpy(dst, hdr->addr1, ETH_ALEN);
1128 memcpy(src, hdr->addr2, ETH_ALEN);
1129
1130 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1131 if (net_ratelimit()) {
1132 printk(KERN_DEBUG "%s: dropped IBSS frame "
1133 "(DA=%s SA=%s BSSID=%s)\n",
1134 dev->name,
1135 print_mac(mac, hdr->addr1),
1136 print_mac(mac2, hdr->addr2),
1137 print_mac(mac3, hdr->addr3));
1138 }
1139 return TXRX_DROP;
1140 }
1141 break;
1142 }
1143
1144 payload = skb->data + hdrlen;
1145
1146 if (unlikely(skb->len - hdrlen < 8)) {
1147 if (net_ratelimit()) {
1148 printk(KERN_DEBUG "%s: RX too short data frame "
1149 "payload\n", dev->name);
1150 }
1151 return TXRX_DROP;
1152 }
1153
1154 ethertype = (payload[6] << 8) | payload[7];
1155
1156 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1157 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1158 compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1159 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1160 * replace EtherType */
1161 skb_pull(skb, hdrlen + 6);
1162 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1163 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1164 } else {
1165 struct ethhdr *ehdr;
1166 __be16 len;
1167 skb_pull(skb, hdrlen);
1168 len = htons(skb->len);
1169 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1170 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1171 memcpy(ehdr->h_source, src, ETH_ALEN);
1172 ehdr->h_proto = len;
1173 }
1174 skb->dev = dev;
1175
1176 skb2 = NULL;
1177
1178 dev->stats.rx_packets++;
1179 dev->stats.rx_bytes += skb->len;
1180
1181 if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1182 || sdata->type == IEEE80211_IF_TYPE_VLAN) &&
1183 (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1184 if (is_multicast_ether_addr(skb->data)) {
1185 /* send multicast frames both to higher layers in
1186 * local net stack and back to the wireless media */
1187 skb2 = skb_copy(skb, GFP_ATOMIC);
1188 if (!skb2 && net_ratelimit())
1189 printk(KERN_DEBUG "%s: failed to clone "
1190 "multicast frame\n", dev->name);
1191 } else {
1192 struct sta_info *dsta;
1193 dsta = sta_info_get(local, skb->data);
1194 if (dsta && !dsta->dev) {
1195 if (net_ratelimit())
1196 printk(KERN_DEBUG "Station with null "
1197 "dev structure!\n");
1198 } else if (dsta && dsta->dev == dev) {
1199 /* Destination station is associated to this
1200 * AP, so send the frame directly to it and
1201 * do not pass the frame to local net stack.
1202 */
1203 skb2 = skb;
1204 skb = NULL;
1205 }
1206 if (dsta)
1207 sta_info_put(dsta);
1208 }
1209 }
1210
1211 if (skb) {
1212 /* deliver to local stack */
1213 skb->protocol = eth_type_trans(skb, dev);
1214 memset(skb->cb, 0, sizeof(skb->cb));
1215 netif_rx(skb);
1216 }
1217
1218 if (skb2) {
1219 /* send to wireless media */
1220 skb2->protocol = __constant_htons(ETH_P_802_3);
1221 skb_set_network_header(skb2, 0);
1222 skb_set_mac_header(skb2, 0);
1223 dev_queue_xmit(skb2);
1224 }
1225
1226 return TXRX_QUEUED;
1227 }
1228
1229 static ieee80211_txrx_result
1230 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1231 {
1232 struct ieee80211_sub_if_data *sdata;
1233
1234 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1235 return TXRX_DROP;
1236
1237 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1238 if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1239 sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1240 !rx->local->user_space_mlme) {
1241 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1242 } else {
1243 /* Management frames are sent to hostapd for processing */
1244 if (!rx->local->apdev)
1245 return TXRX_DROP;
1246 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
1247 ieee80211_msg_normal);
1248 }
1249 return TXRX_QUEUED;
1250 }
1251
1252 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1253 struct ieee80211_local *local,
1254 ieee80211_rx_handler *handlers,
1255 struct ieee80211_txrx_data *rx,
1256 struct sta_info *sta)
1257 {
1258 ieee80211_rx_handler *handler;
1259 ieee80211_txrx_result res = TXRX_DROP;
1260
1261 for (handler = handlers; *handler != NULL; handler++) {
1262 res = (*handler)(rx);
1263
1264 switch (res) {
1265 case TXRX_CONTINUE:
1266 continue;
1267 case TXRX_DROP:
1268 I802_DEBUG_INC(local->rx_handlers_drop);
1269 if (sta)
1270 sta->rx_dropped++;
1271 break;
1272 case TXRX_QUEUED:
1273 I802_DEBUG_INC(local->rx_handlers_queued);
1274 break;
1275 }
1276 break;
1277 }
1278
1279 if (res == TXRX_DROP)
1280 dev_kfree_skb(rx->skb);
1281 return res;
1282 }
1283
1284 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1285 ieee80211_rx_handler *handlers,
1286 struct ieee80211_txrx_data *rx,
1287 struct sta_info *sta)
1288 {
1289 if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1290 TXRX_CONTINUE)
1291 dev_kfree_skb(rx->skb);
1292 }
1293
1294 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1295 struct ieee80211_hdr *hdr,
1296 struct sta_info *sta,
1297 struct ieee80211_txrx_data *rx)
1298 {
1299 int keyidx, hdrlen;
1300 DECLARE_MAC_BUF(mac);
1301 DECLARE_MAC_BUF(mac2);
1302
1303 hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1304 if (rx->skb->len >= hdrlen + 4)
1305 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1306 else
1307 keyidx = -1;
1308
1309 if (net_ratelimit())
1310 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1311 "failure from %s to %s keyidx=%d\n",
1312 dev->name, print_mac(mac, hdr->addr2),
1313 print_mac(mac2, hdr->addr1), keyidx);
1314
1315 if (!sta) {
1316 /*
1317 * Some hardware seem to generate incorrect Michael MIC
1318 * reports; ignore them to avoid triggering countermeasures.
1319 */
1320 if (net_ratelimit())
1321 printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1322 "error for unknown address %s\n",
1323 dev->name, print_mac(mac, hdr->addr2));
1324 goto ignore;
1325 }
1326
1327 if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1328 if (net_ratelimit())
1329 printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1330 "error for a frame with no PROTECTED flag (src "
1331 "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1332 goto ignore;
1333 }
1334
1335 if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1336 /*
1337 * APs with pairwise keys should never receive Michael MIC
1338 * errors for non-zero keyidx because these are reserved for
1339 * group keys and only the AP is sending real multicast
1340 * frames in the BSS.
1341 */
1342 if (net_ratelimit())
1343 printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1344 "a frame with non-zero keyidx (%d)"
1345 " (src %s)\n", dev->name, keyidx,
1346 print_mac(mac, hdr->addr2));
1347 goto ignore;
1348 }
1349
1350 if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1351 ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1352 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1353 if (net_ratelimit())
1354 printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1355 "error for a frame that cannot be encrypted "
1356 "(fc=0x%04x) (src %s)\n",
1357 dev->name, rx->fc, print_mac(mac, hdr->addr2));
1358 goto ignore;
1359 }
1360
1361 mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1362 ignore:
1363 dev_kfree_skb(rx->skb);
1364 rx->skb = NULL;
1365 }
1366
1367 ieee80211_rx_handler ieee80211_rx_handlers[] =
1368 {
1369 ieee80211_rx_h_if_stats,
1370 ieee80211_rx_h_passive_scan,
1371 ieee80211_rx_h_check,
1372 ieee80211_rx_h_load_key,
1373 ieee80211_rx_h_sta_process,
1374 ieee80211_rx_h_ccmp_decrypt,
1375 ieee80211_rx_h_tkip_decrypt,
1376 ieee80211_rx_h_wep_weak_iv_detection,
1377 ieee80211_rx_h_wep_decrypt,
1378 ieee80211_rx_h_defragment,
1379 ieee80211_rx_h_ps_poll,
1380 ieee80211_rx_h_michael_mic_verify,
1381 /* this must be after decryption - so header is counted in MPDU mic
1382 * must be before pae and data, so QOS_DATA format frames
1383 * are not passed to user space by these functions
1384 */
1385 ieee80211_rx_h_remove_qos_control,
1386 ieee80211_rx_h_802_1x_pae,
1387 ieee80211_rx_h_drop_unencrypted,
1388 ieee80211_rx_h_data,
1389 ieee80211_rx_h_mgmt,
1390 NULL
1391 };
1392
1393 /* main receive path */
1394
1395 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1396 u8 *bssid, struct ieee80211_txrx_data *rx,
1397 struct ieee80211_hdr *hdr)
1398 {
1399 int multicast = is_multicast_ether_addr(hdr->addr1);
1400
1401 switch (sdata->type) {
1402 case IEEE80211_IF_TYPE_STA:
1403 if (!bssid)
1404 return 0;
1405 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1406 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1407 return 0;
1408 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1409 } else if (!multicast &&
1410 compare_ether_addr(sdata->dev->dev_addr,
1411 hdr->addr1) != 0) {
1412 if (!(sdata->dev->flags & IFF_PROMISC))
1413 return 0;
1414 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1415 }
1416 break;
1417 case IEEE80211_IF_TYPE_IBSS:
1418 if (!bssid)
1419 return 0;
1420 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1421 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1422 return 0;
1423 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1424 } else if (!multicast &&
1425 compare_ether_addr(sdata->dev->dev_addr,
1426 hdr->addr1) != 0) {
1427 if (!(sdata->dev->flags & IFF_PROMISC))
1428 return 0;
1429 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1430 } else if (!rx->sta)
1431 rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1432 bssid, hdr->addr2);
1433 break;
1434 case IEEE80211_IF_TYPE_AP:
1435 if (!bssid) {
1436 if (compare_ether_addr(sdata->dev->dev_addr,
1437 hdr->addr1))
1438 return 0;
1439 } else if (!ieee80211_bssid_match(bssid,
1440 sdata->dev->dev_addr)) {
1441 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1442 return 0;
1443 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1444 }
1445 if (sdata->dev == sdata->local->mdev &&
1446 !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1447 /* do not receive anything via
1448 * master device when not scanning */
1449 return 0;
1450 break;
1451 case IEEE80211_IF_TYPE_WDS:
1452 if (bssid ||
1453 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1454 return 0;
1455 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1456 return 0;
1457 break;
1458 }
1459
1460 return 1;
1461 }
1462
1463 /*
1464 * This is the receive path handler. It is called by a low level driver when an
1465 * 802.11 MPDU is received from the hardware.
1466 */
1467 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1468 struct ieee80211_rx_status *status)
1469 {
1470 struct ieee80211_local *local = hw_to_local(hw);
1471 struct ieee80211_sub_if_data *sdata;
1472 struct sta_info *sta;
1473 struct ieee80211_hdr *hdr;
1474 struct ieee80211_txrx_data rx;
1475 u16 type;
1476 int prepres;
1477 struct ieee80211_sub_if_data *prev = NULL;
1478 struct sk_buff *skb_new;
1479 u8 *bssid;
1480
1481 /*
1482 * key references and virtual interfaces are protected using RCU
1483 * and this requires that we are in a read-side RCU section during
1484 * receive processing
1485 */
1486 rcu_read_lock();
1487
1488 /*
1489 * Frames with failed FCS/PLCP checksum are not returned,
1490 * all other frames are returned without radiotap header
1491 * if it was previously present.
1492 * Also, frames with less than 16 bytes are dropped.
1493 */
1494 skb = ieee80211_rx_monitor(local, skb, status);
1495 if (!skb) {
1496 rcu_read_unlock();
1497 return;
1498 }
1499
1500 hdr = (struct ieee80211_hdr *) skb->data;
1501 memset(&rx, 0, sizeof(rx));
1502 rx.skb = skb;
1503 rx.local = local;
1504
1505 rx.u.rx.status = status;
1506 rx.fc = le16_to_cpu(hdr->frame_control);
1507 type = rx.fc & IEEE80211_FCTL_FTYPE;
1508
1509 if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1510 local->dot11ReceivedFragmentCount++;
1511
1512 sta = rx.sta = sta_info_get(local, hdr->addr2);
1513 if (sta) {
1514 rx.dev = rx.sta->dev;
1515 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1516 }
1517
1518 if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1519 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1520 goto end;
1521 }
1522
1523 if (unlikely(local->sta_scanning))
1524 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1525
1526 if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1527 sta) != TXRX_CONTINUE)
1528 goto end;
1529 skb = rx.skb;
1530
1531 if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1532 !local->iff_promiscs && !is_multicast_ether_addr(hdr->addr1)) {
1533 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1534 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1535 rx.sta);
1536 sta_info_put(sta);
1537 rcu_read_unlock();
1538 return;
1539 }
1540
1541 bssid = ieee80211_get_bssid(hdr, skb->len);
1542
1543 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1544 if (!netif_running(sdata->dev))
1545 continue;
1546
1547 if (sdata->type == IEEE80211_IF_TYPE_MNTR)
1548 continue;
1549
1550 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1551 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1552 /* prepare_for_handlers can change sta */
1553 sta = rx.sta;
1554
1555 if (!prepres)
1556 continue;
1557
1558 /*
1559 * frame is destined for this interface, but if it's not
1560 * also for the previous one we handle that after the
1561 * loop to avoid copying the SKB once too much
1562 */
1563
1564 if (!prev) {
1565 prev = sdata;
1566 continue;
1567 }
1568
1569 /*
1570 * frame was destined for the previous interface
1571 * so invoke RX handlers for it
1572 */
1573
1574 skb_new = skb_copy(skb, GFP_ATOMIC);
1575 if (!skb_new) {
1576 if (net_ratelimit())
1577 printk(KERN_DEBUG "%s: failed to copy "
1578 "multicast frame for %s",
1579 wiphy_name(local->hw.wiphy),
1580 prev->dev->name);
1581 continue;
1582 }
1583 rx.skb = skb_new;
1584 rx.dev = prev->dev;
1585 rx.sdata = prev;
1586 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1587 &rx, sta);
1588 prev = sdata;
1589 }
1590 if (prev) {
1591 rx.skb = skb;
1592 rx.dev = prev->dev;
1593 rx.sdata = prev;
1594 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1595 &rx, sta);
1596 } else
1597 dev_kfree_skb(skb);
1598
1599 end:
1600 rcu_read_unlock();
1601
1602 if (sta)
1603 sta_info_put(sta);
1604 }
1605 EXPORT_SYMBOL(__ieee80211_rx);
1606
1607 /* This is a version of the rx handler that can be called from hard irq
1608 * context. Post the skb on the queue and schedule the tasklet */
1609 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1610 struct ieee80211_rx_status *status)
1611 {
1612 struct ieee80211_local *local = hw_to_local(hw);
1613
1614 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1615
1616 skb->dev = local->mdev;
1617 /* copy status into skb->cb for use by tasklet */
1618 memcpy(skb->cb, status, sizeof(*status));
1619 skb->pkt_type = IEEE80211_RX_MSG;
1620 skb_queue_tail(&local->skb_queue, skb);
1621 tasklet_schedule(&local->tasklet);
1622 }
1623 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
Linux kernel - Deliverables
This page took 0.068465 seconds and 4 git commands to generate.