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12#include <linux/if_ether.h>
13#include <linux/etherdevice.h>
14#include <linux/list.h>
15#include <linux/rcupdate.h>
16#include <linux/rtnetlink.h>
17#include <linux/slab.h>
18#include <linux/export.h>
19#include <net/mac80211.h>
20#include <asm/unaligned.h>
21#include "ieee80211_i.h"
22#include "driver-ops.h"
23#include "debugfs_key.h"
24#include "aes_ccm.h"
25#include "aes_cmac.h"
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51static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
52
53static void assert_key_lock(struct ieee80211_local *local)
54{
55 lockdep_assert_held(&local->key_mtx);
56}
57
58static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
59{
60
61
62
63
64
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66
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74
75
76
77
78
79 if (!sdata->crypto_tx_tailroom_needed_cnt++) {
80
81
82
83
84 synchronize_net();
85 }
86}
87
88static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
89{
90 struct ieee80211_sub_if_data *sdata;
91 struct sta_info *sta;
92 int ret;
93
94 might_sleep();
95
96 if (!key->local->ops->set_key)
97 goto out_unsupported;
98
99 assert_key_lock(key->local);
100
101 sta = key->sta;
102
103
104
105
106
107 if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
108 !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
109 goto out_unsupported;
110
111 if (sta && !sta->uploaded)
112 goto out_unsupported;
113
114 sdata = key->sdata;
115 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
116
117
118
119
120 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
121 goto out_unsupported;
122 }
123
124 ret = drv_set_key(key->local, SET_KEY, sdata,
125 sta ? &sta->sta : NULL, &key->conf);
126
127 if (!ret) {
128 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
129
130 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
131 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
132 (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
133 sdata->crypto_tx_tailroom_needed_cnt--;
134
135 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
136 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
137
138 return 0;
139 }
140
141 if (ret != -ENOSPC && ret != -EOPNOTSUPP)
142 sdata_err(sdata,
143 "failed to set key (%d, %pM) to hardware (%d)\n",
144 key->conf.keyidx,
145 sta ? sta->sta.addr : bcast_addr, ret);
146
147 out_unsupported:
148 switch (key->conf.cipher) {
149 case WLAN_CIPHER_SUITE_WEP40:
150 case WLAN_CIPHER_SUITE_WEP104:
151 case WLAN_CIPHER_SUITE_TKIP:
152 case WLAN_CIPHER_SUITE_CCMP:
153 case WLAN_CIPHER_SUITE_AES_CMAC:
154
155 return 0;
156 default:
157 return -EINVAL;
158 }
159}
160
161static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
162{
163 struct ieee80211_sub_if_data *sdata;
164 struct sta_info *sta;
165 int ret;
166
167 might_sleep();
168
169 if (!key || !key->local->ops->set_key)
170 return;
171
172 assert_key_lock(key->local);
173
174 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
175 return;
176
177 sta = key->sta;
178 sdata = key->sdata;
179
180 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
181 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
182 (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
183 increment_tailroom_need_count(sdata);
184
185 ret = drv_set_key(key->local, DISABLE_KEY, sdata,
186 sta ? &sta->sta : NULL, &key->conf);
187
188 if (ret)
189 sdata_err(sdata,
190 "failed to remove key (%d, %pM) from hardware (%d)\n",
191 key->conf.keyidx,
192 sta ? sta->sta.addr : bcast_addr, ret);
193
194 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
195}
196
197static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
198 int idx, bool uni, bool multi)
199{
200 struct ieee80211_key *key = NULL;
201
202 assert_key_lock(sdata->local);
203
204 if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
205 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
206
207 if (uni) {
208 rcu_assign_pointer(sdata->default_unicast_key, key);
209 drv_set_default_unicast_key(sdata->local, sdata, idx);
210 }
211
212 if (multi)
213 rcu_assign_pointer(sdata->default_multicast_key, key);
214
215 ieee80211_debugfs_key_update_default(sdata);
216}
217
218void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
219 bool uni, bool multi)
220{
221 mutex_lock(&sdata->local->key_mtx);
222 __ieee80211_set_default_key(sdata, idx, uni, multi);
223 mutex_unlock(&sdata->local->key_mtx);
224}
225
226static void
227__ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
228{
229 struct ieee80211_key *key = NULL;
230
231 assert_key_lock(sdata->local);
232
233 if (idx >= NUM_DEFAULT_KEYS &&
234 idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
235 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
236
237 rcu_assign_pointer(sdata->default_mgmt_key, key);
238
239 ieee80211_debugfs_key_update_default(sdata);
240}
241
242void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
243 int idx)
244{
245 mutex_lock(&sdata->local->key_mtx);
246 __ieee80211_set_default_mgmt_key(sdata, idx);
247 mutex_unlock(&sdata->local->key_mtx);
248}
249
250
251static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
252 struct sta_info *sta,
253 bool pairwise,
254 struct ieee80211_key *old,
255 struct ieee80211_key *new)
256{
257 int idx;
258 bool defunikey, defmultikey, defmgmtkey;
259
260 if (new)
261 list_add_tail(&new->list, &sdata->key_list);
262
263 if (sta && pairwise) {
264 rcu_assign_pointer(sta->ptk, new);
265 } else if (sta) {
266 if (old)
267 idx = old->conf.keyidx;
268 else
269 idx = new->conf.keyidx;
270 rcu_assign_pointer(sta->gtk[idx], new);
271 } else {
272 WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
273
274 if (old)
275 idx = old->conf.keyidx;
276 else
277 idx = new->conf.keyidx;
278
279 defunikey = old &&
280 old == key_mtx_dereference(sdata->local,
281 sdata->default_unicast_key);
282 defmultikey = old &&
283 old == key_mtx_dereference(sdata->local,
284 sdata->default_multicast_key);
285 defmgmtkey = old &&
286 old == key_mtx_dereference(sdata->local,
287 sdata->default_mgmt_key);
288
289 if (defunikey && !new)
290 __ieee80211_set_default_key(sdata, -1, true, false);
291 if (defmultikey && !new)
292 __ieee80211_set_default_key(sdata, -1, false, true);
293 if (defmgmtkey && !new)
294 __ieee80211_set_default_mgmt_key(sdata, -1);
295
296 rcu_assign_pointer(sdata->keys[idx], new);
297 if (defunikey && new)
298 __ieee80211_set_default_key(sdata, new->conf.keyidx,
299 true, false);
300 if (defmultikey && new)
301 __ieee80211_set_default_key(sdata, new->conf.keyidx,
302 false, true);
303 if (defmgmtkey && new)
304 __ieee80211_set_default_mgmt_key(sdata,
305 new->conf.keyidx);
306 }
307
308 if (old)
309 list_del(&old->list);
310}
311
312struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
313 const u8 *key_data,
314 size_t seq_len, const u8 *seq)
315{
316 struct ieee80211_key *key;
317 int i, j, err;
318
319 BUG_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS);
320
321 key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
322 if (!key)
323 return ERR_PTR(-ENOMEM);
324
325
326
327
328
329 key->conf.flags = 0;
330 key->flags = 0;
331
332 key->conf.cipher = cipher;
333 key->conf.keyidx = idx;
334 key->conf.keylen = key_len;
335 switch (cipher) {
336 case WLAN_CIPHER_SUITE_WEP40:
337 case WLAN_CIPHER_SUITE_WEP104:
338 key->conf.iv_len = WEP_IV_LEN;
339 key->conf.icv_len = WEP_ICV_LEN;
340 break;
341 case WLAN_CIPHER_SUITE_TKIP:
342 key->conf.iv_len = TKIP_IV_LEN;
343 key->conf.icv_len = TKIP_ICV_LEN;
344 if (seq) {
345 for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
346 key->u.tkip.rx[i].iv32 =
347 get_unaligned_le32(&seq[2]);
348 key->u.tkip.rx[i].iv16 =
349 get_unaligned_le16(seq);
350 }
351 }
352 spin_lock_init(&key->u.tkip.txlock);
353 break;
354 case WLAN_CIPHER_SUITE_CCMP:
355 key->conf.iv_len = CCMP_HDR_LEN;
356 key->conf.icv_len = CCMP_MIC_LEN;
357 if (seq) {
358 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
359 for (j = 0; j < CCMP_PN_LEN; j++)
360 key->u.ccmp.rx_pn[i][j] =
361 seq[CCMP_PN_LEN - j - 1];
362 }
363
364
365
366
367 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
368 if (IS_ERR(key->u.ccmp.tfm)) {
369 err = PTR_ERR(key->u.ccmp.tfm);
370 kfree(key);
371 return ERR_PTR(err);
372 }
373 break;
374 case WLAN_CIPHER_SUITE_AES_CMAC:
375 key->conf.iv_len = 0;
376 key->conf.icv_len = sizeof(struct ieee80211_mmie);
377 if (seq)
378 for (j = 0; j < CMAC_PN_LEN; j++)
379 key->u.aes_cmac.rx_pn[j] =
380 seq[CMAC_PN_LEN - j - 1];
381
382
383
384
385 key->u.aes_cmac.tfm =
386 ieee80211_aes_cmac_key_setup(key_data);
387 if (IS_ERR(key->u.aes_cmac.tfm)) {
388 err = PTR_ERR(key->u.aes_cmac.tfm);
389 kfree(key);
390 return ERR_PTR(err);
391 }
392 break;
393 }
394 memcpy(key->conf.key, key_data, key_len);
395 INIT_LIST_HEAD(&key->list);
396
397 return key;
398}
399
400static void ieee80211_key_free_common(struct ieee80211_key *key)
401{
402 if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
403 ieee80211_aes_key_free(key->u.ccmp.tfm);
404 if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
405 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
406 kfree(key);
407}
408
409static void __ieee80211_key_destroy(struct ieee80211_key *key,
410 bool delay_tailroom)
411{
412 if (key->local)
413 ieee80211_key_disable_hw_accel(key);
414
415 if (key->local) {
416 struct ieee80211_sub_if_data *sdata = key->sdata;
417
418 ieee80211_debugfs_key_remove(key);
419
420 if (delay_tailroom) {
421
422 sdata->crypto_tx_tailroom_pending_dec++;
423 schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
424 HZ/2);
425 } else {
426 sdata->crypto_tx_tailroom_needed_cnt--;
427 }
428 }
429
430 ieee80211_key_free_common(key);
431}
432
433static void ieee80211_key_destroy(struct ieee80211_key *key,
434 bool delay_tailroom)
435{
436 if (!key)
437 return;
438
439
440
441
442
443 synchronize_net();
444
445 __ieee80211_key_destroy(key, delay_tailroom);
446}
447
448void ieee80211_key_free_unused(struct ieee80211_key *key)
449{
450 WARN_ON(key->sdata || key->local);
451 ieee80211_key_free_common(key);
452}
453
454int ieee80211_key_link(struct ieee80211_key *key,
455 struct ieee80211_sub_if_data *sdata,
456 struct sta_info *sta)
457{
458 struct ieee80211_key *old_key;
459 int idx, ret;
460 bool pairwise;
461
462 BUG_ON(!sdata);
463 BUG_ON(!key);
464
465 pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
466 idx = key->conf.keyidx;
467 key->local = sdata->local;
468 key->sdata = sdata;
469 key->sta = sta;
470
471 mutex_lock(&sdata->local->key_mtx);
472
473 if (sta && pairwise)
474 old_key = key_mtx_dereference(sdata->local, sta->ptk);
475 else if (sta)
476 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
477 else
478 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
479
480 increment_tailroom_need_count(sdata);
481
482 ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
483 ieee80211_key_destroy(old_key, true);
484
485 ieee80211_debugfs_key_add(key);
486
487 ret = ieee80211_key_enable_hw_accel(key);
488
489 if (ret)
490 ieee80211_key_free(key, true);
491
492 mutex_unlock(&sdata->local->key_mtx);
493
494 return ret;
495}
496
497void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
498{
499 if (!key)
500 return;
501
502
503
504
505 if (key->sdata)
506 ieee80211_key_replace(key->sdata, key->sta,
507 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
508 key, NULL);
509 ieee80211_key_destroy(key, delay_tailroom);
510}
511
512void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
513{
514 struct ieee80211_key *key;
515
516 ASSERT_RTNL();
517
518 if (WARN_ON(!ieee80211_sdata_running(sdata)))
519 return;
520
521 mutex_lock(&sdata->local->key_mtx);
522
523 sdata->crypto_tx_tailroom_needed_cnt = 0;
524
525 list_for_each_entry(key, &sdata->key_list, list) {
526 increment_tailroom_need_count(sdata);
527 ieee80211_key_enable_hw_accel(key);
528 }
529
530 mutex_unlock(&sdata->local->key_mtx);
531}
532
533void ieee80211_iter_keys(struct ieee80211_hw *hw,
534 struct ieee80211_vif *vif,
535 void (*iter)(struct ieee80211_hw *hw,
536 struct ieee80211_vif *vif,
537 struct ieee80211_sta *sta,
538 struct ieee80211_key_conf *key,
539 void *data),
540 void *iter_data)
541{
542 struct ieee80211_local *local = hw_to_local(hw);
543 struct ieee80211_key *key;
544 struct ieee80211_sub_if_data *sdata;
545
546 ASSERT_RTNL();
547
548 mutex_lock(&local->key_mtx);
549 if (vif) {
550 sdata = vif_to_sdata(vif);
551 list_for_each_entry(key, &sdata->key_list, list)
552 iter(hw, &sdata->vif,
553 key->sta ? &key->sta->sta : NULL,
554 &key->conf, iter_data);
555 } else {
556 list_for_each_entry(sdata, &local->interfaces, list)
557 list_for_each_entry(key, &sdata->key_list, list)
558 iter(hw, &sdata->vif,
559 key->sta ? &key->sta->sta : NULL,
560 &key->conf, iter_data);
561 }
562 mutex_unlock(&local->key_mtx);
563}
564EXPORT_SYMBOL(ieee80211_iter_keys);
565
566void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata)
567{
568 struct ieee80211_key *key, *tmp;
569 LIST_HEAD(keys);
570
571 cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
572
573 mutex_lock(&sdata->local->key_mtx);
574
575 sdata->crypto_tx_tailroom_needed_cnt -=
576 sdata->crypto_tx_tailroom_pending_dec;
577 sdata->crypto_tx_tailroom_pending_dec = 0;
578
579 ieee80211_debugfs_key_remove_mgmt_default(sdata);
580
581 list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
582 ieee80211_key_replace(key->sdata, key->sta,
583 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
584 key, NULL);
585 list_add_tail(&key->list, &keys);
586 }
587
588 ieee80211_debugfs_key_update_default(sdata);
589
590 if (!list_empty(&keys)) {
591 synchronize_net();
592 list_for_each_entry_safe(key, tmp, &keys, list)
593 __ieee80211_key_destroy(key, false);
594 }
595
596 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
597 sdata->crypto_tx_tailroom_pending_dec);
598
599 mutex_unlock(&sdata->local->key_mtx);
600}
601
602void ieee80211_free_sta_keys(struct ieee80211_local *local,
603 struct sta_info *sta)
604{
605 struct ieee80211_key *key, *tmp;
606 LIST_HEAD(keys);
607 int i;
608
609 mutex_lock(&local->key_mtx);
610 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
611 key = key_mtx_dereference(local, sta->gtk[i]);
612 if (!key)
613 continue;
614 ieee80211_key_replace(key->sdata, key->sta,
615 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
616 key, NULL);
617 list_add(&key->list, &keys);
618 }
619
620 key = key_mtx_dereference(local, sta->ptk);
621 if (key) {
622 ieee80211_key_replace(key->sdata, key->sta,
623 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
624 key, NULL);
625 list_add(&key->list, &keys);
626 }
627
628
629
630
631
632 synchronize_net();
633
634 list_for_each_entry_safe(key, tmp, &keys, list)
635 __ieee80211_key_destroy(key, true);
636
637 mutex_unlock(&local->key_mtx);
638}
639
640void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
641{
642 struct ieee80211_sub_if_data *sdata;
643
644 sdata = container_of(wk, struct ieee80211_sub_if_data,
645 dec_tailroom_needed_wk.work);
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663 mutex_lock(&sdata->local->key_mtx);
664 sdata->crypto_tx_tailroom_needed_cnt -=
665 sdata->crypto_tx_tailroom_pending_dec;
666 sdata->crypto_tx_tailroom_pending_dec = 0;
667 mutex_unlock(&sdata->local->key_mtx);
668}
669
670void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
671 const u8 *replay_ctr, gfp_t gfp)
672{
673 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
674
675 trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
676
677 cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
678}
679EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
680
681void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
682 struct ieee80211_key_seq *seq)
683{
684 struct ieee80211_key *key;
685 u64 pn64;
686
687 if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
688 return;
689
690 key = container_of(keyconf, struct ieee80211_key, conf);
691
692 switch (key->conf.cipher) {
693 case WLAN_CIPHER_SUITE_TKIP:
694 seq->tkip.iv32 = key->u.tkip.tx.iv32;
695 seq->tkip.iv16 = key->u.tkip.tx.iv16;
696 break;
697 case WLAN_CIPHER_SUITE_CCMP:
698 pn64 = atomic64_read(&key->u.ccmp.tx_pn);
699 seq->ccmp.pn[5] = pn64;
700 seq->ccmp.pn[4] = pn64 >> 8;
701 seq->ccmp.pn[3] = pn64 >> 16;
702 seq->ccmp.pn[2] = pn64 >> 24;
703 seq->ccmp.pn[1] = pn64 >> 32;
704 seq->ccmp.pn[0] = pn64 >> 40;
705 break;
706 case WLAN_CIPHER_SUITE_AES_CMAC:
707 pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
708 seq->ccmp.pn[5] = pn64;
709 seq->ccmp.pn[4] = pn64 >> 8;
710 seq->ccmp.pn[3] = pn64 >> 16;
711 seq->ccmp.pn[2] = pn64 >> 24;
712 seq->ccmp.pn[1] = pn64 >> 32;
713 seq->ccmp.pn[0] = pn64 >> 40;
714 break;
715 default:
716 WARN_ON(1);
717 }
718}
719EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
720
721void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
722 int tid, struct ieee80211_key_seq *seq)
723{
724 struct ieee80211_key *key;
725 const u8 *pn;
726
727 key = container_of(keyconf, struct ieee80211_key, conf);
728
729 switch (key->conf.cipher) {
730 case WLAN_CIPHER_SUITE_TKIP:
731 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
732 return;
733 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
734 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
735 break;
736 case WLAN_CIPHER_SUITE_CCMP:
737 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
738 return;
739 if (tid < 0)
740 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
741 else
742 pn = key->u.ccmp.rx_pn[tid];
743 memcpy(seq->ccmp.pn, pn, CCMP_PN_LEN);
744 break;
745 case WLAN_CIPHER_SUITE_AES_CMAC:
746 if (WARN_ON(tid != 0))
747 return;
748 pn = key->u.aes_cmac.rx_pn;
749 memcpy(seq->aes_cmac.pn, pn, CMAC_PN_LEN);
750 break;
751 }
752}
753EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
754