xref: /openbmc/linux/net/mac80211/key.c (revision 588b48ca)
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 2007-2008	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/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"
26 
27 
28 /**
29  * DOC: Key handling basics
30  *
31  * Key handling in mac80211 is done based on per-interface (sub_if_data)
32  * keys and per-station keys. Since each station belongs to an interface,
33  * each station key also belongs to that interface.
34  *
35  * Hardware acceleration is done on a best-effort basis for algorithms
36  * that are implemented in software,  for each key the hardware is asked
37  * to enable that key for offloading but if it cannot do that the key is
38  * simply kept for software encryption (unless it is for an algorithm
39  * that isn't implemented in software).
40  * There is currently no way of knowing whether a key is handled in SW
41  * or HW except by looking into debugfs.
42  *
43  * All key management is internally protected by a mutex. Within all
44  * other parts of mac80211, key references are, just as STA structure
45  * references, protected by RCU. Note, however, that some things are
46  * unprotected, namely the key->sta dereferences within the hardware
47  * acceleration functions. This means that sta_info_destroy() must
48  * remove the key which waits for an RCU grace period.
49  */
50 
51 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
52 
53 static void assert_key_lock(struct ieee80211_local *local)
54 {
55 	lockdep_assert_held(&local->key_mtx);
56 }
57 
58 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
59 {
60 	/*
61 	 * When this count is zero, SKB resizing for allocating tailroom
62 	 * for IV or MMIC is skipped. But, this check has created two race
63 	 * cases in xmit path while transiting from zero count to one:
64 	 *
65 	 * 1. SKB resize was skipped because no key was added but just before
66 	 * the xmit key is added and SW encryption kicks off.
67 	 *
68 	 * 2. SKB resize was skipped because all the keys were hw planted but
69 	 * just before xmit one of the key is deleted and SW encryption kicks
70 	 * off.
71 	 *
72 	 * In both the above case SW encryption will find not enough space for
73 	 * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
74 	 *
75 	 * Solution has been explained at
76 	 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
77 	 */
78 
79 	if (!sdata->crypto_tx_tailroom_needed_cnt++) {
80 		/*
81 		 * Flush all XMIT packets currently using HW encryption or no
82 		 * encryption at all if the count transition is from 0 -> 1.
83 		 */
84 		synchronize_net();
85 	}
86 }
87 
88 static 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->flags & KEY_FLAG_TAINTED)
97 		return -EINVAL;
98 
99 	if (!key->local->ops->set_key)
100 		goto out_unsupported;
101 
102 	assert_key_lock(key->local);
103 
104 	sta = key->sta;
105 
106 	/*
107 	 * If this is a per-STA GTK, check if it
108 	 * is supported; if not, return.
109 	 */
110 	if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
111 	    !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
112 		goto out_unsupported;
113 
114 	if (sta && !sta->uploaded)
115 		goto out_unsupported;
116 
117 	sdata = key->sdata;
118 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
119 		/*
120 		 * The driver doesn't know anything about VLAN interfaces.
121 		 * Hence, don't send GTKs for VLAN interfaces to the driver.
122 		 */
123 		if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
124 			goto out_unsupported;
125 	}
126 
127 	ret = drv_set_key(key->local, SET_KEY, sdata,
128 			  sta ? &sta->sta : NULL, &key->conf);
129 
130 	if (!ret) {
131 		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
132 
133 		if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
134 		      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
135 		      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
136 			sdata->crypto_tx_tailroom_needed_cnt--;
137 
138 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
139 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
140 
141 		return 0;
142 	}
143 
144 	if (ret != -ENOSPC && ret != -EOPNOTSUPP)
145 		sdata_err(sdata,
146 			  "failed to set key (%d, %pM) to hardware (%d)\n",
147 			  key->conf.keyidx,
148 			  sta ? sta->sta.addr : bcast_addr, ret);
149 
150  out_unsupported:
151 	switch (key->conf.cipher) {
152 	case WLAN_CIPHER_SUITE_WEP40:
153 	case WLAN_CIPHER_SUITE_WEP104:
154 	case WLAN_CIPHER_SUITE_TKIP:
155 	case WLAN_CIPHER_SUITE_CCMP:
156 	case WLAN_CIPHER_SUITE_AES_CMAC:
157 		/* all of these we can do in software */
158 		return 0;
159 	default:
160 		return -EINVAL;
161 	}
162 }
163 
164 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
165 {
166 	struct ieee80211_sub_if_data *sdata;
167 	struct sta_info *sta;
168 	int ret;
169 
170 	might_sleep();
171 
172 	if (!key || !key->local->ops->set_key)
173 		return;
174 
175 	assert_key_lock(key->local);
176 
177 	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
178 		return;
179 
180 	sta = key->sta;
181 	sdata = key->sdata;
182 
183 	if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
184 	      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
185 	      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
186 		increment_tailroom_need_count(sdata);
187 
188 	ret = drv_set_key(key->local, DISABLE_KEY, sdata,
189 			  sta ? &sta->sta : NULL, &key->conf);
190 
191 	if (ret)
192 		sdata_err(sdata,
193 			  "failed to remove key (%d, %pM) from hardware (%d)\n",
194 			  key->conf.keyidx,
195 			  sta ? sta->sta.addr : bcast_addr, ret);
196 
197 	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
198 }
199 
200 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
201 					int idx, bool uni, bool multi)
202 {
203 	struct ieee80211_key *key = NULL;
204 
205 	assert_key_lock(sdata->local);
206 
207 	if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
208 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
209 
210 	if (uni) {
211 		rcu_assign_pointer(sdata->default_unicast_key, key);
212 		drv_set_default_unicast_key(sdata->local, sdata, idx);
213 	}
214 
215 	if (multi)
216 		rcu_assign_pointer(sdata->default_multicast_key, key);
217 
218 	ieee80211_debugfs_key_update_default(sdata);
219 }
220 
221 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
222 			       bool uni, bool multi)
223 {
224 	mutex_lock(&sdata->local->key_mtx);
225 	__ieee80211_set_default_key(sdata, idx, uni, multi);
226 	mutex_unlock(&sdata->local->key_mtx);
227 }
228 
229 static void
230 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
231 {
232 	struct ieee80211_key *key = NULL;
233 
234 	assert_key_lock(sdata->local);
235 
236 	if (idx >= NUM_DEFAULT_KEYS &&
237 	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
238 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
239 
240 	rcu_assign_pointer(sdata->default_mgmt_key, key);
241 
242 	ieee80211_debugfs_key_update_default(sdata);
243 }
244 
245 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
246 				    int idx)
247 {
248 	mutex_lock(&sdata->local->key_mtx);
249 	__ieee80211_set_default_mgmt_key(sdata, idx);
250 	mutex_unlock(&sdata->local->key_mtx);
251 }
252 
253 
254 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
255 				  struct sta_info *sta,
256 				  bool pairwise,
257 				  struct ieee80211_key *old,
258 				  struct ieee80211_key *new)
259 {
260 	int idx;
261 	bool defunikey, defmultikey, defmgmtkey;
262 
263 	/* caller must provide at least one old/new */
264 	if (WARN_ON(!new && !old))
265 		return;
266 
267 	if (new)
268 		list_add_tail(&new->list, &sdata->key_list);
269 
270 	WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
271 
272 	if (old)
273 		idx = old->conf.keyidx;
274 	else
275 		idx = new->conf.keyidx;
276 
277 	if (sta) {
278 		if (pairwise) {
279 			rcu_assign_pointer(sta->ptk[idx], new);
280 			sta->ptk_idx = idx;
281 		} else {
282 			rcu_assign_pointer(sta->gtk[idx], new);
283 			sta->gtk_idx = idx;
284 		}
285 	} else {
286 		defunikey = old &&
287 			old == key_mtx_dereference(sdata->local,
288 						sdata->default_unicast_key);
289 		defmultikey = old &&
290 			old == key_mtx_dereference(sdata->local,
291 						sdata->default_multicast_key);
292 		defmgmtkey = old &&
293 			old == key_mtx_dereference(sdata->local,
294 						sdata->default_mgmt_key);
295 
296 		if (defunikey && !new)
297 			__ieee80211_set_default_key(sdata, -1, true, false);
298 		if (defmultikey && !new)
299 			__ieee80211_set_default_key(sdata, -1, false, true);
300 		if (defmgmtkey && !new)
301 			__ieee80211_set_default_mgmt_key(sdata, -1);
302 
303 		rcu_assign_pointer(sdata->keys[idx], new);
304 		if (defunikey && new)
305 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
306 						    true, false);
307 		if (defmultikey && new)
308 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
309 						    false, true);
310 		if (defmgmtkey && new)
311 			__ieee80211_set_default_mgmt_key(sdata,
312 							 new->conf.keyidx);
313 	}
314 
315 	if (old)
316 		list_del(&old->list);
317 }
318 
319 struct ieee80211_key *
320 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
321 		    const u8 *key_data,
322 		    size_t seq_len, const u8 *seq,
323 		    const struct ieee80211_cipher_scheme *cs)
324 {
325 	struct ieee80211_key *key;
326 	int i, j, err;
327 
328 	if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
329 		return ERR_PTR(-EINVAL);
330 
331 	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
332 	if (!key)
333 		return ERR_PTR(-ENOMEM);
334 
335 	/*
336 	 * Default to software encryption; we'll later upload the
337 	 * key to the hardware if possible.
338 	 */
339 	key->conf.flags = 0;
340 	key->flags = 0;
341 
342 	key->conf.cipher = cipher;
343 	key->conf.keyidx = idx;
344 	key->conf.keylen = key_len;
345 	switch (cipher) {
346 	case WLAN_CIPHER_SUITE_WEP40:
347 	case WLAN_CIPHER_SUITE_WEP104:
348 		key->conf.iv_len = IEEE80211_WEP_IV_LEN;
349 		key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
350 		break;
351 	case WLAN_CIPHER_SUITE_TKIP:
352 		key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
353 		key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
354 		if (seq) {
355 			for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
356 				key->u.tkip.rx[i].iv32 =
357 					get_unaligned_le32(&seq[2]);
358 				key->u.tkip.rx[i].iv16 =
359 					get_unaligned_le16(seq);
360 			}
361 		}
362 		spin_lock_init(&key->u.tkip.txlock);
363 		break;
364 	case WLAN_CIPHER_SUITE_CCMP:
365 		key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
366 		key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
367 		if (seq) {
368 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
369 				for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
370 					key->u.ccmp.rx_pn[i][j] =
371 						seq[IEEE80211_CCMP_PN_LEN - j - 1];
372 		}
373 		/*
374 		 * Initialize AES key state here as an optimization so that
375 		 * it does not need to be initialized for every packet.
376 		 */
377 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
378 		if (IS_ERR(key->u.ccmp.tfm)) {
379 			err = PTR_ERR(key->u.ccmp.tfm);
380 			kfree(key);
381 			return ERR_PTR(err);
382 		}
383 		break;
384 	case WLAN_CIPHER_SUITE_AES_CMAC:
385 		key->conf.iv_len = 0;
386 		key->conf.icv_len = sizeof(struct ieee80211_mmie);
387 		if (seq)
388 			for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
389 				key->u.aes_cmac.rx_pn[j] =
390 					seq[IEEE80211_CMAC_PN_LEN - j - 1];
391 		/*
392 		 * Initialize AES key state here as an optimization so that
393 		 * it does not need to be initialized for every packet.
394 		 */
395 		key->u.aes_cmac.tfm =
396 			ieee80211_aes_cmac_key_setup(key_data);
397 		if (IS_ERR(key->u.aes_cmac.tfm)) {
398 			err = PTR_ERR(key->u.aes_cmac.tfm);
399 			kfree(key);
400 			return ERR_PTR(err);
401 		}
402 		break;
403 	default:
404 		if (cs) {
405 			size_t len = (seq_len > MAX_PN_LEN) ?
406 						MAX_PN_LEN : seq_len;
407 
408 			key->conf.iv_len = cs->hdr_len;
409 			key->conf.icv_len = cs->mic_len;
410 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
411 				for (j = 0; j < len; j++)
412 					key->u.gen.rx_pn[i][j] =
413 							seq[len - j - 1];
414 		}
415 	}
416 	memcpy(key->conf.key, key_data, key_len);
417 	INIT_LIST_HEAD(&key->list);
418 
419 	return key;
420 }
421 
422 static void ieee80211_key_free_common(struct ieee80211_key *key)
423 {
424 	if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
425 		ieee80211_aes_key_free(key->u.ccmp.tfm);
426 	if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
427 		ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
428 	kfree(key);
429 }
430 
431 static void __ieee80211_key_destroy(struct ieee80211_key *key,
432 				    bool delay_tailroom)
433 {
434 	if (key->local)
435 		ieee80211_key_disable_hw_accel(key);
436 
437 	if (key->local) {
438 		struct ieee80211_sub_if_data *sdata = key->sdata;
439 
440 		ieee80211_debugfs_key_remove(key);
441 
442 		if (delay_tailroom) {
443 			/* see ieee80211_delayed_tailroom_dec */
444 			sdata->crypto_tx_tailroom_pending_dec++;
445 			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
446 					      HZ/2);
447 		} else {
448 			sdata->crypto_tx_tailroom_needed_cnt--;
449 		}
450 	}
451 
452 	ieee80211_key_free_common(key);
453 }
454 
455 static void ieee80211_key_destroy(struct ieee80211_key *key,
456 				  bool delay_tailroom)
457 {
458 	if (!key)
459 		return;
460 
461 	/*
462 	 * Synchronize so the TX path can no longer be using
463 	 * this key before we free/remove it.
464 	 */
465 	synchronize_net();
466 
467 	__ieee80211_key_destroy(key, delay_tailroom);
468 }
469 
470 void ieee80211_key_free_unused(struct ieee80211_key *key)
471 {
472 	WARN_ON(key->sdata || key->local);
473 	ieee80211_key_free_common(key);
474 }
475 
476 int ieee80211_key_link(struct ieee80211_key *key,
477 		       struct ieee80211_sub_if_data *sdata,
478 		       struct sta_info *sta)
479 {
480 	struct ieee80211_local *local = sdata->local;
481 	struct ieee80211_key *old_key;
482 	int idx, ret;
483 	bool pairwise;
484 
485 	pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
486 	idx = key->conf.keyidx;
487 	key->local = sdata->local;
488 	key->sdata = sdata;
489 	key->sta = sta;
490 
491 	mutex_lock(&sdata->local->key_mtx);
492 
493 	if (sta && pairwise)
494 		old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
495 	else if (sta)
496 		old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
497 	else
498 		old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
499 
500 	increment_tailroom_need_count(sdata);
501 
502 	ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
503 	ieee80211_key_destroy(old_key, true);
504 
505 	ieee80211_debugfs_key_add(key);
506 
507 	if (!local->wowlan) {
508 		ret = ieee80211_key_enable_hw_accel(key);
509 		if (ret)
510 			ieee80211_key_free(key, true);
511 	} else {
512 		ret = 0;
513 	}
514 
515 	mutex_unlock(&sdata->local->key_mtx);
516 
517 	return ret;
518 }
519 
520 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
521 {
522 	if (!key)
523 		return;
524 
525 	/*
526 	 * Replace key with nothingness if it was ever used.
527 	 */
528 	if (key->sdata)
529 		ieee80211_key_replace(key->sdata, key->sta,
530 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
531 				key, NULL);
532 	ieee80211_key_destroy(key, delay_tailroom);
533 }
534 
535 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
536 {
537 	struct ieee80211_key *key;
538 
539 	ASSERT_RTNL();
540 
541 	if (WARN_ON(!ieee80211_sdata_running(sdata)))
542 		return;
543 
544 	mutex_lock(&sdata->local->key_mtx);
545 
546 	sdata->crypto_tx_tailroom_needed_cnt = 0;
547 
548 	list_for_each_entry(key, &sdata->key_list, list) {
549 		increment_tailroom_need_count(sdata);
550 		ieee80211_key_enable_hw_accel(key);
551 	}
552 
553 	mutex_unlock(&sdata->local->key_mtx);
554 }
555 
556 void ieee80211_iter_keys(struct ieee80211_hw *hw,
557 			 struct ieee80211_vif *vif,
558 			 void (*iter)(struct ieee80211_hw *hw,
559 				      struct ieee80211_vif *vif,
560 				      struct ieee80211_sta *sta,
561 				      struct ieee80211_key_conf *key,
562 				      void *data),
563 			 void *iter_data)
564 {
565 	struct ieee80211_local *local = hw_to_local(hw);
566 	struct ieee80211_key *key, *tmp;
567 	struct ieee80211_sub_if_data *sdata;
568 
569 	ASSERT_RTNL();
570 
571 	mutex_lock(&local->key_mtx);
572 	if (vif) {
573 		sdata = vif_to_sdata(vif);
574 		list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
575 			iter(hw, &sdata->vif,
576 			     key->sta ? &key->sta->sta : NULL,
577 			     &key->conf, iter_data);
578 	} else {
579 		list_for_each_entry(sdata, &local->interfaces, list)
580 			list_for_each_entry_safe(key, tmp,
581 						 &sdata->key_list, list)
582 				iter(hw, &sdata->vif,
583 				     key->sta ? &key->sta->sta : NULL,
584 				     &key->conf, iter_data);
585 	}
586 	mutex_unlock(&local->key_mtx);
587 }
588 EXPORT_SYMBOL(ieee80211_iter_keys);
589 
590 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
591 				      struct list_head *keys)
592 {
593 	struct ieee80211_key *key, *tmp;
594 
595 	sdata->crypto_tx_tailroom_needed_cnt -=
596 		sdata->crypto_tx_tailroom_pending_dec;
597 	sdata->crypto_tx_tailroom_pending_dec = 0;
598 
599 	ieee80211_debugfs_key_remove_mgmt_default(sdata);
600 
601 	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
602 		ieee80211_key_replace(key->sdata, key->sta,
603 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
604 				key, NULL);
605 		list_add_tail(&key->list, keys);
606 	}
607 
608 	ieee80211_debugfs_key_update_default(sdata);
609 }
610 
611 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
612 			 bool force_synchronize)
613 {
614 	struct ieee80211_local *local = sdata->local;
615 	struct ieee80211_sub_if_data *vlan;
616 	struct ieee80211_key *key, *tmp;
617 	LIST_HEAD(keys);
618 
619 	cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
620 
621 	mutex_lock(&local->key_mtx);
622 
623 	ieee80211_free_keys_iface(sdata, &keys);
624 
625 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
626 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
627 			ieee80211_free_keys_iface(vlan, &keys);
628 	}
629 
630 	if (!list_empty(&keys) || force_synchronize)
631 		synchronize_net();
632 	list_for_each_entry_safe(key, tmp, &keys, list)
633 		__ieee80211_key_destroy(key, false);
634 
635 	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
636 		     sdata->crypto_tx_tailroom_pending_dec);
637 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
638 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
639 			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
640 				     vlan->crypto_tx_tailroom_pending_dec);
641 	}
642 
643 	mutex_unlock(&local->key_mtx);
644 }
645 
646 void ieee80211_free_sta_keys(struct ieee80211_local *local,
647 			     struct sta_info *sta)
648 {
649 	struct ieee80211_key *key;
650 	int i;
651 
652 	mutex_lock(&local->key_mtx);
653 	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
654 		key = key_mtx_dereference(local, sta->gtk[i]);
655 		if (!key)
656 			continue;
657 		ieee80211_key_replace(key->sdata, key->sta,
658 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
659 				key, NULL);
660 		__ieee80211_key_destroy(key, true);
661 	}
662 
663 	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
664 		key = key_mtx_dereference(local, sta->ptk[i]);
665 		if (!key)
666 			continue;
667 		ieee80211_key_replace(key->sdata, key->sta,
668 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
669 				key, NULL);
670 		__ieee80211_key_destroy(key, true);
671 	}
672 
673 	mutex_unlock(&local->key_mtx);
674 }
675 
676 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
677 {
678 	struct ieee80211_sub_if_data *sdata;
679 
680 	sdata = container_of(wk, struct ieee80211_sub_if_data,
681 			     dec_tailroom_needed_wk.work);
682 
683 	/*
684 	 * The reason for the delayed tailroom needed decrementing is to
685 	 * make roaming faster: during roaming, all keys are first deleted
686 	 * and then new keys are installed. The first new key causes the
687 	 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
688 	 * the cost of synchronize_net() (which can be slow). Avoid this
689 	 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
690 	 * key removal for a while, so if we roam the value is larger than
691 	 * zero and no 0->1 transition happens.
692 	 *
693 	 * The cost is that if the AP switching was from an AP with keys
694 	 * to one without, we still allocate tailroom while it would no
695 	 * longer be needed. However, in the typical (fast) roaming case
696 	 * within an ESS this usually won't happen.
697 	 */
698 
699 	mutex_lock(&sdata->local->key_mtx);
700 	sdata->crypto_tx_tailroom_needed_cnt -=
701 		sdata->crypto_tx_tailroom_pending_dec;
702 	sdata->crypto_tx_tailroom_pending_dec = 0;
703 	mutex_unlock(&sdata->local->key_mtx);
704 }
705 
706 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
707 				const u8 *replay_ctr, gfp_t gfp)
708 {
709 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
710 
711 	trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
712 
713 	cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
714 }
715 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
716 
717 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
718 			      struct ieee80211_key_seq *seq)
719 {
720 	struct ieee80211_key *key;
721 	u64 pn64;
722 
723 	if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
724 		return;
725 
726 	key = container_of(keyconf, struct ieee80211_key, conf);
727 
728 	switch (key->conf.cipher) {
729 	case WLAN_CIPHER_SUITE_TKIP:
730 		seq->tkip.iv32 = key->u.tkip.tx.iv32;
731 		seq->tkip.iv16 = key->u.tkip.tx.iv16;
732 		break;
733 	case WLAN_CIPHER_SUITE_CCMP:
734 		pn64 = atomic64_read(&key->u.ccmp.tx_pn);
735 		seq->ccmp.pn[5] = pn64;
736 		seq->ccmp.pn[4] = pn64 >> 8;
737 		seq->ccmp.pn[3] = pn64 >> 16;
738 		seq->ccmp.pn[2] = pn64 >> 24;
739 		seq->ccmp.pn[1] = pn64 >> 32;
740 		seq->ccmp.pn[0] = pn64 >> 40;
741 		break;
742 	case WLAN_CIPHER_SUITE_AES_CMAC:
743 		pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
744 		seq->ccmp.pn[5] = pn64;
745 		seq->ccmp.pn[4] = pn64 >> 8;
746 		seq->ccmp.pn[3] = pn64 >> 16;
747 		seq->ccmp.pn[2] = pn64 >> 24;
748 		seq->ccmp.pn[1] = pn64 >> 32;
749 		seq->ccmp.pn[0] = pn64 >> 40;
750 		break;
751 	default:
752 		WARN_ON(1);
753 	}
754 }
755 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
756 
757 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
758 			      int tid, struct ieee80211_key_seq *seq)
759 {
760 	struct ieee80211_key *key;
761 	const u8 *pn;
762 
763 	key = container_of(keyconf, struct ieee80211_key, conf);
764 
765 	switch (key->conf.cipher) {
766 	case WLAN_CIPHER_SUITE_TKIP:
767 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
768 			return;
769 		seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
770 		seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
771 		break;
772 	case WLAN_CIPHER_SUITE_CCMP:
773 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
774 			return;
775 		if (tid < 0)
776 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
777 		else
778 			pn = key->u.ccmp.rx_pn[tid];
779 		memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
780 		break;
781 	case WLAN_CIPHER_SUITE_AES_CMAC:
782 		if (WARN_ON(tid != 0))
783 			return;
784 		pn = key->u.aes_cmac.rx_pn;
785 		memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
786 		break;
787 	}
788 }
789 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
790 
791 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
792 			      struct ieee80211_key_seq *seq)
793 {
794 	struct ieee80211_key *key;
795 	u64 pn64;
796 
797 	key = container_of(keyconf, struct ieee80211_key, conf);
798 
799 	switch (key->conf.cipher) {
800 	case WLAN_CIPHER_SUITE_TKIP:
801 		key->u.tkip.tx.iv32 = seq->tkip.iv32;
802 		key->u.tkip.tx.iv16 = seq->tkip.iv16;
803 		break;
804 	case WLAN_CIPHER_SUITE_CCMP:
805 		pn64 = (u64)seq->ccmp.pn[5] |
806 		       ((u64)seq->ccmp.pn[4] << 8) |
807 		       ((u64)seq->ccmp.pn[3] << 16) |
808 		       ((u64)seq->ccmp.pn[2] << 24) |
809 		       ((u64)seq->ccmp.pn[1] << 32) |
810 		       ((u64)seq->ccmp.pn[0] << 40);
811 		atomic64_set(&key->u.ccmp.tx_pn, pn64);
812 		break;
813 	case WLAN_CIPHER_SUITE_AES_CMAC:
814 		pn64 = (u64)seq->aes_cmac.pn[5] |
815 		       ((u64)seq->aes_cmac.pn[4] << 8) |
816 		       ((u64)seq->aes_cmac.pn[3] << 16) |
817 		       ((u64)seq->aes_cmac.pn[2] << 24) |
818 		       ((u64)seq->aes_cmac.pn[1] << 32) |
819 		       ((u64)seq->aes_cmac.pn[0] << 40);
820 		atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
821 		break;
822 	default:
823 		WARN_ON(1);
824 		break;
825 	}
826 }
827 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
828 
829 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
830 			      int tid, struct ieee80211_key_seq *seq)
831 {
832 	struct ieee80211_key *key;
833 	u8 *pn;
834 
835 	key = container_of(keyconf, struct ieee80211_key, conf);
836 
837 	switch (key->conf.cipher) {
838 	case WLAN_CIPHER_SUITE_TKIP:
839 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
840 			return;
841 		key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
842 		key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
843 		break;
844 	case WLAN_CIPHER_SUITE_CCMP:
845 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
846 			return;
847 		if (tid < 0)
848 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
849 		else
850 			pn = key->u.ccmp.rx_pn[tid];
851 		memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
852 		break;
853 	case WLAN_CIPHER_SUITE_AES_CMAC:
854 		if (WARN_ON(tid != 0))
855 			return;
856 		pn = key->u.aes_cmac.rx_pn;
857 		memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
858 		break;
859 	default:
860 		WARN_ON(1);
861 		break;
862 	}
863 }
864 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
865 
866 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
867 {
868 	struct ieee80211_key *key;
869 
870 	key = container_of(keyconf, struct ieee80211_key, conf);
871 
872 	assert_key_lock(key->local);
873 
874 	/*
875 	 * if key was uploaded, we assume the driver will/has remove(d)
876 	 * it, so adjust bookkeeping accordingly
877 	 */
878 	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
879 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
880 
881 		if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
882 		      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
883 		      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
884 			increment_tailroom_need_count(key->sdata);
885 	}
886 
887 	ieee80211_key_free(key, false);
888 }
889 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
890 
891 struct ieee80211_key_conf *
892 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
893 			struct ieee80211_key_conf *keyconf)
894 {
895 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
896 	struct ieee80211_local *local = sdata->local;
897 	struct ieee80211_key *key;
898 	int err;
899 
900 	if (WARN_ON(!local->wowlan))
901 		return ERR_PTR(-EINVAL);
902 
903 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
904 		return ERR_PTR(-EINVAL);
905 
906 	key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
907 				  keyconf->keylen, keyconf->key,
908 				  0, NULL, NULL);
909 	if (IS_ERR(key))
910 		return ERR_CAST(key);
911 
912 	if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
913 		key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
914 
915 	err = ieee80211_key_link(key, sdata, NULL);
916 	if (err)
917 		return ERR_PTR(err);
918 
919 	return &key->conf;
920 }
921 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
922