Merge branch 'linus' into core/rcu
[linux-2.6] / net / mac80211 / wpa.c
1 /*
2  * Copyright 2002-2004, Instant802 Networks, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8
9 #include <linux/netdevice.h>
10 #include <linux/types.h>
11 #include <linux/slab.h>
12 #include <linux/skbuff.h>
13 #include <linux/compiler.h>
14 #include <net/mac80211.h>
15
16 #include "ieee80211_i.h"
17 #include "michael.h"
18 #include "tkip.h"
19 #include "aes_ccm.h"
20 #include "wpa.h"
21
22 static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da,
23                                   u8 *qos_tid, u8 **data, size_t *data_len)
24 {
25         struct ieee80211_hdr *hdr;
26         size_t hdrlen;
27         u16 fc;
28         int a4_included;
29         u8 *pos;
30
31         hdr = (struct ieee80211_hdr *) skb->data;
32         fc = le16_to_cpu(hdr->frame_control);
33
34         hdrlen = 24;
35         if ((fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) ==
36             (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
37                 hdrlen += ETH_ALEN;
38                 *sa = hdr->addr4;
39                 *da = hdr->addr3;
40         } else if (fc & IEEE80211_FCTL_FROMDS) {
41                 *sa = hdr->addr3;
42                 *da = hdr->addr1;
43         } else if (fc & IEEE80211_FCTL_TODS) {
44                 *sa = hdr->addr2;
45                 *da = hdr->addr3;
46         } else {
47                 *sa = hdr->addr2;
48                 *da = hdr->addr1;
49         }
50
51         if (fc & 0x80)
52                 hdrlen += 2;
53
54         *data = skb->data + hdrlen;
55         *data_len = skb->len - hdrlen;
56
57         a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
58                 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);
59         if ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
60             fc & IEEE80211_STYPE_QOS_DATA) {
61                 pos = (u8 *) &hdr->addr4;
62                 if (a4_included)
63                         pos += 6;
64                 *qos_tid = pos[0] & 0x0f;
65                 *qos_tid |= 0x80; /* qos_included flag */
66         } else
67                 *qos_tid = 0;
68
69         return skb->len < hdrlen ? -1 : 0;
70 }
71
72
73 ieee80211_tx_result
74 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
75 {
76         u8 *data, *sa, *da, *key, *mic, qos_tid;
77         size_t data_len;
78         u16 fc;
79         struct sk_buff *skb = tx->skb;
80         int authenticator;
81         int wpa_test = 0;
82
83         fc = tx->fc;
84
85         if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||
86             !WLAN_FC_DATA_PRESENT(fc))
87                 return TX_CONTINUE;
88
89         if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
90                 return TX_DROP;
91
92         if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
93             !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
94             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
95             !wpa_test) {
96                 /* hwaccel - with no need for preallocated room for Michael MIC
97                  */
98                 return TX_CONTINUE;
99         }
100
101         if (skb_tailroom(skb) < MICHAEL_MIC_LEN) {
102                 I802_DEBUG_INC(tx->local->tx_expand_skb_head);
103                 if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN,
104                                               MICHAEL_MIC_LEN + TKIP_ICV_LEN,
105                                               GFP_ATOMIC))) {
106                         printk(KERN_DEBUG "%s: failed to allocate more memory "
107                                "for Michael MIC\n", tx->dev->name);
108                         return TX_DROP;
109                 }
110         }
111
112 #if 0
113         authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
114 #else
115         authenticator = 1;
116 #endif
117         key = &tx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :
118                                  ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];
119         mic = skb_put(skb, MICHAEL_MIC_LEN);
120         michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
121
122         return TX_CONTINUE;
123 }
124
125
126 ieee80211_rx_result
127 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
128 {
129         u8 *data, *sa, *da, *key = NULL, qos_tid;
130         size_t data_len;
131         u16 fc;
132         u8 mic[MICHAEL_MIC_LEN];
133         struct sk_buff *skb = rx->skb;
134         int authenticator = 1, wpa_test = 0;
135         DECLARE_MAC_BUF(mac);
136
137         fc = rx->fc;
138
139         /*
140          * No way to verify the MIC if the hardware stripped it
141          */
142         if (rx->status->flag & RX_FLAG_MMIC_STRIPPED)
143                 return RX_CONTINUE;
144
145         if (!rx->key || rx->key->conf.alg != ALG_TKIP ||
146             !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc))
147                 return RX_CONTINUE;
148
149         if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
150             || data_len < MICHAEL_MIC_LEN)
151                 return RX_DROP_UNUSABLE;
152
153         data_len -= MICHAEL_MIC_LEN;
154
155 #if 0
156         authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
157 #else
158         authenticator = 1;
159 #endif
160         key = &rx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :
161                                  ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];
162         michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
163         if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
164                 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
165                         return RX_DROP_UNUSABLE;
166
167                 printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from "
168                        "%s\n", rx->dev->name, print_mac(mac, sa));
169
170                 mac80211_ev_michael_mic_failure(rx->dev, rx->key->conf.keyidx,
171                                                 (void *) skb->data);
172                 return RX_DROP_UNUSABLE;
173         }
174
175         /* remove Michael MIC from payload */
176         skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
177
178         /* update IV in key information to be able to detect replays */
179         rx->key->u.tkip.iv32_rx[rx->queue] = rx->tkip_iv32;
180         rx->key->u.tkip.iv16_rx[rx->queue] = rx->tkip_iv16;
181
182         return RX_CONTINUE;
183 }
184
185
186 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx,
187                             struct sk_buff *skb, int test)
188 {
189         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
190         struct ieee80211_key *key = tx->key;
191         int hdrlen, len, tailneed;
192         u16 fc;
193         u8 *pos;
194
195         fc = le16_to_cpu(hdr->frame_control);
196         hdrlen = ieee80211_get_hdrlen(fc);
197         len = skb->len - hdrlen;
198
199         if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
200                 tailneed = 0;
201         else
202                 tailneed = TKIP_ICV_LEN;
203
204         if ((skb_headroom(skb) < TKIP_IV_LEN ||
205              skb_tailroom(skb) < tailneed)) {
206                 I802_DEBUG_INC(tx->local->tx_expand_skb_head);
207                 if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,
208                                               GFP_ATOMIC)))
209                         return -1;
210         }
211
212         pos = skb_push(skb, TKIP_IV_LEN);
213         memmove(pos, pos + TKIP_IV_LEN, hdrlen);
214         pos += hdrlen;
215
216         /* Increase IV for the frame */
217         key->u.tkip.iv16++;
218         if (key->u.tkip.iv16 == 0)
219                 key->u.tkip.iv32++;
220
221         if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
222                 hdr = (struct ieee80211_hdr *)skb->data;
223
224                 /* hwaccel - with preallocated room for IV */
225                 ieee80211_tkip_add_iv(pos, key,
226                                       (u8) (key->u.tkip.iv16 >> 8),
227                                       (u8) (((key->u.tkip.iv16 >> 8) | 0x20) &
228                                             0x7f),
229                                       (u8) key->u.tkip.iv16);
230
231                 tx->control->key_idx = tx->key->conf.hw_key_idx;
232                 return 0;
233         }
234
235         /* Add room for ICV */
236         skb_put(skb, TKIP_ICV_LEN);
237
238         hdr = (struct ieee80211_hdr *) skb->data;
239         ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
240                                     key, pos, len, hdr->addr2);
241         return 0;
242 }
243
244
245 ieee80211_tx_result
246 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
247 {
248         struct sk_buff *skb = tx->skb;
249         int wpa_test = 0, test = 0;
250
251         tx->control->icv_len = TKIP_ICV_LEN;
252         tx->control->iv_len = TKIP_IV_LEN;
253         ieee80211_tx_set_protected(tx);
254
255         if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
256             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
257             !wpa_test) {
258                 /* hwaccel - with no need for preallocated room for IV/ICV */
259                 tx->control->key_idx = tx->key->conf.hw_key_idx;
260                 return TX_CONTINUE;
261         }
262
263         if (tkip_encrypt_skb(tx, skb, test) < 0)
264                 return TX_DROP;
265
266         if (tx->extra_frag) {
267                 int i;
268                 for (i = 0; i < tx->num_extra_frag; i++) {
269                         if (tkip_encrypt_skb(tx, tx->extra_frag[i], test)
270                             < 0)
271                                 return TX_DROP;
272                 }
273         }
274
275         return TX_CONTINUE;
276 }
277
278
279 ieee80211_rx_result
280 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
281 {
282         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
283         u16 fc;
284         int hdrlen, res, hwaccel = 0, wpa_test = 0;
285         struct ieee80211_key *key = rx->key;
286         struct sk_buff *skb = rx->skb;
287         DECLARE_MAC_BUF(mac);
288
289         fc = le16_to_cpu(hdr->frame_control);
290         hdrlen = ieee80211_get_hdrlen(fc);
291
292         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
293                 return RX_CONTINUE;
294
295         if (!rx->sta || skb->len - hdrlen < 12)
296                 return RX_DROP_UNUSABLE;
297
298         if (rx->status->flag & RX_FLAG_DECRYPTED) {
299                 if (rx->status->flag & RX_FLAG_IV_STRIPPED) {
300                         /*
301                          * Hardware took care of all processing, including
302                          * replay protection, and stripped the ICV/IV so
303                          * we cannot do any checks here.
304                          */
305                         return RX_CONTINUE;
306                 }
307
308                 /* let TKIP code verify IV, but skip decryption */
309                 hwaccel = 1;
310         }
311
312         res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
313                                           key, skb->data + hdrlen,
314                                           skb->len - hdrlen, rx->sta->addr,
315                                           hdr->addr1, hwaccel, rx->queue,
316                                           &rx->tkip_iv32,
317                                           &rx->tkip_iv16);
318         if (res != TKIP_DECRYPT_OK || wpa_test) {
319 #ifdef CONFIG_MAC80211_DEBUG
320                 if (net_ratelimit())
321                         printk(KERN_DEBUG "%s: TKIP decrypt failed for RX "
322                                "frame from %s (res=%d)\n", rx->dev->name,
323                                print_mac(mac, rx->sta->addr), res);
324 #endif /* CONFIG_MAC80211_DEBUG */
325                 return RX_DROP_UNUSABLE;
326         }
327
328         /* Trim ICV */
329         skb_trim(skb, skb->len - TKIP_ICV_LEN);
330
331         /* Remove IV */
332         memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
333         skb_pull(skb, TKIP_IV_LEN);
334
335         return RX_CONTINUE;
336 }
337
338
339 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,
340                                 int encrypted)
341 {
342         u16 fc;
343         int a4_included, qos_included;
344         u8 qos_tid, *fc_pos, *data, *sa, *da;
345         int len_a;
346         size_t data_len;
347         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
348
349         fc_pos = (u8 *) &hdr->frame_control;
350         fc = fc_pos[0] ^ (fc_pos[1] << 8);
351         a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
352                 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);
353
354         ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len);
355         data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0);
356         if (qos_tid & 0x80) {
357                 qos_included = 1;
358                 qos_tid &= 0x0f;
359         } else
360                 qos_included = 0;
361         /* First block, b_0 */
362
363         b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
364         /* Nonce: QoS Priority | A2 | PN */
365         b_0[1] = qos_tid;
366         memcpy(&b_0[2], hdr->addr2, 6);
367         memcpy(&b_0[8], pn, CCMP_PN_LEN);
368         /* l(m) */
369         b_0[14] = (data_len >> 8) & 0xff;
370         b_0[15] = data_len & 0xff;
371
372
373         /* AAD (extra authenticate-only data) / masked 802.11 header
374          * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
375
376         len_a = a4_included ? 28 : 22;
377         if (qos_included)
378                 len_a += 2;
379
380         aad[0] = 0; /* (len_a >> 8) & 0xff; */
381         aad[1] = len_a & 0xff;
382         /* Mask FC: zero subtype b4 b5 b6 */
383         aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6));
384         /* Retry, PwrMgt, MoreData; set Protected */
385         aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6);
386         memcpy(&aad[4], &hdr->addr1, 18);
387
388         /* Mask Seq#, leave Frag# */
389         aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
390         aad[23] = 0;
391         if (a4_included) {
392                 memcpy(&aad[24], hdr->addr4, 6);
393                 aad[30] = 0;
394                 aad[31] = 0;
395         } else
396                 memset(&aad[24], 0, 8);
397         if (qos_included) {
398                 u8 *dpos = &aad[a4_included ? 30 : 24];
399
400                 /* Mask QoS Control field */
401                 dpos[0] = qos_tid;
402                 dpos[1] = 0;
403         }
404 }
405
406
407 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
408 {
409         hdr[0] = pn[5];
410         hdr[1] = pn[4];
411         hdr[2] = 0;
412         hdr[3] = 0x20 | (key_id << 6);
413         hdr[4] = pn[3];
414         hdr[5] = pn[2];
415         hdr[6] = pn[1];
416         hdr[7] = pn[0];
417 }
418
419
420 static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr)
421 {
422         pn[0] = hdr[7];
423         pn[1] = hdr[6];
424         pn[2] = hdr[5];
425         pn[3] = hdr[4];
426         pn[4] = hdr[1];
427         pn[5] = hdr[0];
428         return (hdr[3] >> 6) & 0x03;
429 }
430
431
432 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx,
433                             struct sk_buff *skb, int test)
434 {
435         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
436         struct ieee80211_key *key = tx->key;
437         int hdrlen, len, tailneed;
438         u16 fc;
439         u8 *pos, *pn, *b_0, *aad, *scratch;
440         int i;
441
442         scratch = key->u.ccmp.tx_crypto_buf;
443         b_0 = scratch + 3 * AES_BLOCK_LEN;
444         aad = scratch + 4 * AES_BLOCK_LEN;
445
446         fc = le16_to_cpu(hdr->frame_control);
447         hdrlen = ieee80211_get_hdrlen(fc);
448         len = skb->len - hdrlen;
449
450         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
451                 tailneed = 0;
452         else
453                 tailneed = CCMP_MIC_LEN;
454
455         if ((skb_headroom(skb) < CCMP_HDR_LEN ||
456              skb_tailroom(skb) < tailneed)) {
457                 I802_DEBUG_INC(tx->local->tx_expand_skb_head);
458                 if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,
459                                               GFP_ATOMIC)))
460                         return -1;
461         }
462
463         pos = skb_push(skb, CCMP_HDR_LEN);
464         memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
465         hdr = (struct ieee80211_hdr *) pos;
466         pos += hdrlen;
467
468         /* PN = PN + 1 */
469         pn = key->u.ccmp.tx_pn;
470
471         for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
472                 pn[i]++;
473                 if (pn[i])
474                         break;
475         }
476
477         ccmp_pn2hdr(pos, pn, key->conf.keyidx);
478
479         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
480                 /* hwaccel - with preallocated room for CCMP header */
481                 tx->control->key_idx = key->conf.hw_key_idx;
482                 return 0;
483         }
484
485         pos += CCMP_HDR_LEN;
486         ccmp_special_blocks(skb, pn, b_0, aad, 0);
487         ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
488                                   pos, skb_put(skb, CCMP_MIC_LEN));
489
490         return 0;
491 }
492
493
494 ieee80211_tx_result
495 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
496 {
497         struct sk_buff *skb = tx->skb;
498         int test = 0;
499
500         tx->control->icv_len = CCMP_MIC_LEN;
501         tx->control->iv_len = CCMP_HDR_LEN;
502         ieee80211_tx_set_protected(tx);
503
504         if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
505             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
506                 /* hwaccel - with no need for preallocated room for CCMP "
507                  * header or MIC fields */
508                 tx->control->key_idx = tx->key->conf.hw_key_idx;
509                 return TX_CONTINUE;
510         }
511
512         if (ccmp_encrypt_skb(tx, skb, test) < 0)
513                 return TX_DROP;
514
515         if (tx->extra_frag) {
516                 int i;
517                 for (i = 0; i < tx->num_extra_frag; i++) {
518                         if (ccmp_encrypt_skb(tx, tx->extra_frag[i], test)
519                             < 0)
520                                 return TX_DROP;
521                 }
522         }
523
524         return TX_CONTINUE;
525 }
526
527
528 ieee80211_rx_result
529 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
530 {
531         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
532         u16 fc;
533         int hdrlen;
534         struct ieee80211_key *key = rx->key;
535         struct sk_buff *skb = rx->skb;
536         u8 pn[CCMP_PN_LEN];
537         int data_len;
538         DECLARE_MAC_BUF(mac);
539
540         fc = le16_to_cpu(hdr->frame_control);
541         hdrlen = ieee80211_get_hdrlen(fc);
542
543         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
544                 return RX_CONTINUE;
545
546         data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
547         if (!rx->sta || data_len < 0)
548                 return RX_DROP_UNUSABLE;
549
550         if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
551             (rx->status->flag & RX_FLAG_IV_STRIPPED))
552                 return RX_CONTINUE;
553
554         (void) ccmp_hdr2pn(pn, skb->data + hdrlen);
555
556         if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
557 #ifdef CONFIG_MAC80211_DEBUG
558                 u8 *ppn = key->u.ccmp.rx_pn[rx->queue];
559
560                 printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from "
561                        "%s (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "
562                        "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name,
563                        print_mac(mac, rx->sta->addr),
564                        pn[0], pn[1], pn[2], pn[3], pn[4], pn[5],
565                        ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]);
566 #endif /* CONFIG_MAC80211_DEBUG */
567                 key->u.ccmp.replays++;
568                 return RX_DROP_UNUSABLE;
569         }
570
571         if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
572                 /* hardware didn't decrypt/verify MIC */
573                 u8 *scratch, *b_0, *aad;
574
575                 scratch = key->u.ccmp.rx_crypto_buf;
576                 b_0 = scratch + 3 * AES_BLOCK_LEN;
577                 aad = scratch + 4 * AES_BLOCK_LEN;
578
579                 ccmp_special_blocks(skb, pn, b_0, aad, 1);
580
581                 if (ieee80211_aes_ccm_decrypt(
582                             key->u.ccmp.tfm, scratch, b_0, aad,
583                             skb->data + hdrlen + CCMP_HDR_LEN, data_len,
584                             skb->data + skb->len - CCMP_MIC_LEN,
585                             skb->data + hdrlen + CCMP_HDR_LEN)) {
586 #ifdef CONFIG_MAC80211_DEBUG
587                         if (net_ratelimit())
588                                 printk(KERN_DEBUG "%s: CCMP decrypt failed "
589                                        "for RX frame from %s\n", rx->dev->name,
590                                        print_mac(mac, rx->sta->addr));
591 #endif /* CONFIG_MAC80211_DEBUG */
592                         return RX_DROP_UNUSABLE;
593                 }
594         }
595
596         memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);
597
598         /* Remove CCMP header and MIC */
599         skb_trim(skb, skb->len - CCMP_MIC_LEN);
600         memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
601         skb_pull(skb, CCMP_HDR_LEN);
602
603         return RX_CONTINUE;
604 }