xref: /linux/net/mac80211/key.c (revision 5e8c0fb6a95728b852d56c0a9244425d474670c0)
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  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/if_ether.h>
14 #include <linux/etherdevice.h>
15 #include <linux/list.h>
16 #include <linux/rcupdate.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/slab.h>
19 #include <linux/export.h>
20 #include <net/mac80211.h>
21 #include <asm/unaligned.h>
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "debugfs_key.h"
25 #include "aes_ccm.h"
26 #include "aes_cmac.h"
27 
28 
29 /**
30  * DOC: Key handling basics
31  *
32  * Key handling in mac80211 is done based on per-interface (sub_if_data)
33  * keys and per-station keys. Since each station belongs to an interface,
34  * each station key also belongs to that interface.
35  *
36  * Hardware acceleration is done on a best-effort basis for algorithms
37  * that are implemented in software,  for each key the hardware is asked
38  * to enable that key for offloading but if it cannot do that the key is
39  * simply kept for software encryption (unless it is for an algorithm
40  * that isn't implemented in software).
41  * There is currently no way of knowing whether a key is handled in SW
42  * or HW except by looking into debugfs.
43  *
44  * All key management is internally protected by a mutex. Within all
45  * other parts of mac80211, key references are, just as STA structure
46  * references, protected by RCU. Note, however, that some things are
47  * unprotected, namely the key->sta dereferences within the hardware
48  * acceleration functions. This means that sta_info_destroy() must
49  * remove the key which waits for an RCU grace period.
50  */
51 
52 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
53 
54 static void assert_key_lock(struct ieee80211_local *local)
55 {
56 	lockdep_assert_held(&local->key_mtx);
57 }
58 
59 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
60 {
61 	/*
62 	 * When this count is zero, SKB resizing for allocating tailroom
63 	 * for IV or MMIC is skipped. But, this check has created two race
64 	 * cases in xmit path while transiting from zero count to one:
65 	 *
66 	 * 1. SKB resize was skipped because no key was added but just before
67 	 * the xmit key is added and SW encryption kicks off.
68 	 *
69 	 * 2. SKB resize was skipped because all the keys were hw planted but
70 	 * just before xmit one of the key is deleted and SW encryption kicks
71 	 * off.
72 	 *
73 	 * In both the above case SW encryption will find not enough space for
74 	 * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
75 	 *
76 	 * Solution has been explained at
77 	 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
78 	 */
79 
80 	if (!sdata->crypto_tx_tailroom_needed_cnt++) {
81 		/*
82 		 * Flush all XMIT packets currently using HW encryption or no
83 		 * encryption at all if the count transition is from 0 -> 1.
84 		 */
85 		synchronize_net();
86 	}
87 }
88 
89 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
90 {
91 	struct ieee80211_sub_if_data *sdata;
92 	struct sta_info *sta;
93 	int ret;
94 
95 	might_sleep();
96 
97 	if (key->flags & KEY_FLAG_TAINTED) {
98 		/* If we get here, it's during resume and the key is
99 		 * tainted so shouldn't be used/programmed any more.
100 		 * However, its flags may still indicate that it was
101 		 * programmed into the device (since we're in resume)
102 		 * so clear that flag now to avoid trying to remove
103 		 * it again later.
104 		 */
105 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
106 		return -EINVAL;
107 	}
108 
109 	if (!key->local->ops->set_key)
110 		goto out_unsupported;
111 
112 	assert_key_lock(key->local);
113 
114 	sta = key->sta;
115 
116 	/*
117 	 * If this is a per-STA GTK, check if it
118 	 * is supported; if not, return.
119 	 */
120 	if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
121 	    !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
122 		goto out_unsupported;
123 
124 	if (sta && !sta->uploaded)
125 		goto out_unsupported;
126 
127 	sdata = key->sdata;
128 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
129 		/*
130 		 * The driver doesn't know anything about VLAN interfaces.
131 		 * Hence, don't send GTKs for VLAN interfaces to the driver.
132 		 */
133 		if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
134 			goto out_unsupported;
135 	}
136 
137 	ret = drv_set_key(key->local, SET_KEY, sdata,
138 			  sta ? &sta->sta : NULL, &key->conf);
139 
140 	if (!ret) {
141 		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
142 
143 		if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
144 		      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
145 		      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
146 			sdata->crypto_tx_tailroom_needed_cnt--;
147 
148 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
149 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
150 
151 		return 0;
152 	}
153 
154 	if (ret != -ENOSPC && ret != -EOPNOTSUPP)
155 		sdata_err(sdata,
156 			  "failed to set key (%d, %pM) to hardware (%d)\n",
157 			  key->conf.keyidx,
158 			  sta ? sta->sta.addr : bcast_addr, ret);
159 
160  out_unsupported:
161 	switch (key->conf.cipher) {
162 	case WLAN_CIPHER_SUITE_WEP40:
163 	case WLAN_CIPHER_SUITE_WEP104:
164 	case WLAN_CIPHER_SUITE_TKIP:
165 	case WLAN_CIPHER_SUITE_CCMP:
166 	case WLAN_CIPHER_SUITE_AES_CMAC:
167 		/* all of these we can do in software */
168 		return 0;
169 	default:
170 		return -EINVAL;
171 	}
172 }
173 
174 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
175 {
176 	struct ieee80211_sub_if_data *sdata;
177 	struct sta_info *sta;
178 	int ret;
179 
180 	might_sleep();
181 
182 	if (!key || !key->local->ops->set_key)
183 		return;
184 
185 	assert_key_lock(key->local);
186 
187 	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
188 		return;
189 
190 	sta = key->sta;
191 	sdata = key->sdata;
192 
193 	if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
194 	      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
195 	      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
196 		increment_tailroom_need_count(sdata);
197 
198 	ret = drv_set_key(key->local, DISABLE_KEY, sdata,
199 			  sta ? &sta->sta : NULL, &key->conf);
200 
201 	if (ret)
202 		sdata_err(sdata,
203 			  "failed to remove key (%d, %pM) from hardware (%d)\n",
204 			  key->conf.keyidx,
205 			  sta ? sta->sta.addr : bcast_addr, ret);
206 
207 	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
208 }
209 
210 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
211 					int idx, bool uni, bool multi)
212 {
213 	struct ieee80211_key *key = NULL;
214 
215 	assert_key_lock(sdata->local);
216 
217 	if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
218 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
219 
220 	if (uni) {
221 		rcu_assign_pointer(sdata->default_unicast_key, key);
222 		drv_set_default_unicast_key(sdata->local, sdata, idx);
223 	}
224 
225 	if (multi)
226 		rcu_assign_pointer(sdata->default_multicast_key, key);
227 
228 	ieee80211_debugfs_key_update_default(sdata);
229 }
230 
231 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
232 			       bool uni, bool multi)
233 {
234 	mutex_lock(&sdata->local->key_mtx);
235 	__ieee80211_set_default_key(sdata, idx, uni, multi);
236 	mutex_unlock(&sdata->local->key_mtx);
237 }
238 
239 static void
240 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
241 {
242 	struct ieee80211_key *key = NULL;
243 
244 	assert_key_lock(sdata->local);
245 
246 	if (idx >= NUM_DEFAULT_KEYS &&
247 	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
248 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
249 
250 	rcu_assign_pointer(sdata->default_mgmt_key, key);
251 
252 	ieee80211_debugfs_key_update_default(sdata);
253 }
254 
255 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
256 				    int idx)
257 {
258 	mutex_lock(&sdata->local->key_mtx);
259 	__ieee80211_set_default_mgmt_key(sdata, idx);
260 	mutex_unlock(&sdata->local->key_mtx);
261 }
262 
263 
264 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
265 				  struct sta_info *sta,
266 				  bool pairwise,
267 				  struct ieee80211_key *old,
268 				  struct ieee80211_key *new)
269 {
270 	int idx;
271 	bool defunikey, defmultikey, defmgmtkey;
272 
273 	/* caller must provide at least one old/new */
274 	if (WARN_ON(!new && !old))
275 		return;
276 
277 	if (new)
278 		list_add_tail(&new->list, &sdata->key_list);
279 
280 	WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
281 
282 	if (old)
283 		idx = old->conf.keyidx;
284 	else
285 		idx = new->conf.keyidx;
286 
287 	if (sta) {
288 		if (pairwise) {
289 			rcu_assign_pointer(sta->ptk[idx], new);
290 			sta->ptk_idx = idx;
291 		} else {
292 			rcu_assign_pointer(sta->gtk[idx], new);
293 			sta->gtk_idx = idx;
294 		}
295 	} else {
296 		defunikey = old &&
297 			old == key_mtx_dereference(sdata->local,
298 						sdata->default_unicast_key);
299 		defmultikey = old &&
300 			old == key_mtx_dereference(sdata->local,
301 						sdata->default_multicast_key);
302 		defmgmtkey = old &&
303 			old == key_mtx_dereference(sdata->local,
304 						sdata->default_mgmt_key);
305 
306 		if (defunikey && !new)
307 			__ieee80211_set_default_key(sdata, -1, true, false);
308 		if (defmultikey && !new)
309 			__ieee80211_set_default_key(sdata, -1, false, true);
310 		if (defmgmtkey && !new)
311 			__ieee80211_set_default_mgmt_key(sdata, -1);
312 
313 		rcu_assign_pointer(sdata->keys[idx], new);
314 		if (defunikey && new)
315 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
316 						    true, false);
317 		if (defmultikey && new)
318 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
319 						    false, true);
320 		if (defmgmtkey && new)
321 			__ieee80211_set_default_mgmt_key(sdata,
322 							 new->conf.keyidx);
323 	}
324 
325 	if (old)
326 		list_del(&old->list);
327 }
328 
329 struct ieee80211_key *
330 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
331 		    const u8 *key_data,
332 		    size_t seq_len, const u8 *seq,
333 		    const struct ieee80211_cipher_scheme *cs)
334 {
335 	struct ieee80211_key *key;
336 	int i, j, err;
337 
338 	if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
339 		return ERR_PTR(-EINVAL);
340 
341 	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
342 	if (!key)
343 		return ERR_PTR(-ENOMEM);
344 
345 	/*
346 	 * Default to software encryption; we'll later upload the
347 	 * key to the hardware if possible.
348 	 */
349 	key->conf.flags = 0;
350 	key->flags = 0;
351 
352 	key->conf.cipher = cipher;
353 	key->conf.keyidx = idx;
354 	key->conf.keylen = key_len;
355 	switch (cipher) {
356 	case WLAN_CIPHER_SUITE_WEP40:
357 	case WLAN_CIPHER_SUITE_WEP104:
358 		key->conf.iv_len = IEEE80211_WEP_IV_LEN;
359 		key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
360 		break;
361 	case WLAN_CIPHER_SUITE_TKIP:
362 		key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
363 		key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
364 		if (seq) {
365 			for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
366 				key->u.tkip.rx[i].iv32 =
367 					get_unaligned_le32(&seq[2]);
368 				key->u.tkip.rx[i].iv16 =
369 					get_unaligned_le16(seq);
370 			}
371 		}
372 		spin_lock_init(&key->u.tkip.txlock);
373 		break;
374 	case WLAN_CIPHER_SUITE_CCMP:
375 		key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
376 		key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
377 		if (seq) {
378 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
379 				for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
380 					key->u.ccmp.rx_pn[i][j] =
381 						seq[IEEE80211_CCMP_PN_LEN - j - 1];
382 		}
383 		/*
384 		 * Initialize AES key state here as an optimization so that
385 		 * it does not need to be initialized for every packet.
386 		 */
387 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
388 		if (IS_ERR(key->u.ccmp.tfm)) {
389 			err = PTR_ERR(key->u.ccmp.tfm);
390 			kfree(key);
391 			return ERR_PTR(err);
392 		}
393 		break;
394 	case WLAN_CIPHER_SUITE_AES_CMAC:
395 		key->conf.iv_len = 0;
396 		key->conf.icv_len = sizeof(struct ieee80211_mmie);
397 		if (seq)
398 			for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
399 				key->u.aes_cmac.rx_pn[j] =
400 					seq[IEEE80211_CMAC_PN_LEN - j - 1];
401 		/*
402 		 * Initialize AES key state here as an optimization so that
403 		 * it does not need to be initialized for every packet.
404 		 */
405 		key->u.aes_cmac.tfm =
406 			ieee80211_aes_cmac_key_setup(key_data);
407 		if (IS_ERR(key->u.aes_cmac.tfm)) {
408 			err = PTR_ERR(key->u.aes_cmac.tfm);
409 			kfree(key);
410 			return ERR_PTR(err);
411 		}
412 		break;
413 	default:
414 		if (cs) {
415 			size_t len = (seq_len > MAX_PN_LEN) ?
416 						MAX_PN_LEN : seq_len;
417 
418 			key->conf.iv_len = cs->hdr_len;
419 			key->conf.icv_len = cs->mic_len;
420 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
421 				for (j = 0; j < len; j++)
422 					key->u.gen.rx_pn[i][j] =
423 							seq[len - j - 1];
424 		}
425 	}
426 	memcpy(key->conf.key, key_data, key_len);
427 	INIT_LIST_HEAD(&key->list);
428 
429 	return key;
430 }
431 
432 static void ieee80211_key_free_common(struct ieee80211_key *key)
433 {
434 	if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
435 		ieee80211_aes_key_free(key->u.ccmp.tfm);
436 	if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
437 		ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
438 	kzfree(key);
439 }
440 
441 static void __ieee80211_key_destroy(struct ieee80211_key *key,
442 				    bool delay_tailroom)
443 {
444 	if (key->local)
445 		ieee80211_key_disable_hw_accel(key);
446 
447 	if (key->local) {
448 		struct ieee80211_sub_if_data *sdata = key->sdata;
449 
450 		ieee80211_debugfs_key_remove(key);
451 
452 		if (delay_tailroom) {
453 			/* see ieee80211_delayed_tailroom_dec */
454 			sdata->crypto_tx_tailroom_pending_dec++;
455 			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
456 					      HZ/2);
457 		} else {
458 			sdata->crypto_tx_tailroom_needed_cnt--;
459 		}
460 	}
461 
462 	ieee80211_key_free_common(key);
463 }
464 
465 static void ieee80211_key_destroy(struct ieee80211_key *key,
466 				  bool delay_tailroom)
467 {
468 	if (!key)
469 		return;
470 
471 	/*
472 	 * Synchronize so the TX path can no longer be using
473 	 * this key before we free/remove it.
474 	 */
475 	synchronize_net();
476 
477 	__ieee80211_key_destroy(key, delay_tailroom);
478 }
479 
480 void ieee80211_key_free_unused(struct ieee80211_key *key)
481 {
482 	WARN_ON(key->sdata || key->local);
483 	ieee80211_key_free_common(key);
484 }
485 
486 int ieee80211_key_link(struct ieee80211_key *key,
487 		       struct ieee80211_sub_if_data *sdata,
488 		       struct sta_info *sta)
489 {
490 	struct ieee80211_local *local = sdata->local;
491 	struct ieee80211_key *old_key;
492 	int idx, ret;
493 	bool pairwise;
494 
495 	pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
496 	idx = key->conf.keyidx;
497 	key->local = sdata->local;
498 	key->sdata = sdata;
499 	key->sta = sta;
500 
501 	mutex_lock(&sdata->local->key_mtx);
502 
503 	if (sta && pairwise)
504 		old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
505 	else if (sta)
506 		old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
507 	else
508 		old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
509 
510 	increment_tailroom_need_count(sdata);
511 
512 	ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
513 	ieee80211_key_destroy(old_key, true);
514 
515 	ieee80211_debugfs_key_add(key);
516 
517 	if (!local->wowlan) {
518 		ret = ieee80211_key_enable_hw_accel(key);
519 		if (ret)
520 			ieee80211_key_free(key, true);
521 	} else {
522 		ret = 0;
523 	}
524 
525 	mutex_unlock(&sdata->local->key_mtx);
526 
527 	return ret;
528 }
529 
530 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
531 {
532 	if (!key)
533 		return;
534 
535 	/*
536 	 * Replace key with nothingness if it was ever used.
537 	 */
538 	if (key->sdata)
539 		ieee80211_key_replace(key->sdata, key->sta,
540 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
541 				key, NULL);
542 	ieee80211_key_destroy(key, delay_tailroom);
543 }
544 
545 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
546 {
547 	struct ieee80211_key *key;
548 
549 	ASSERT_RTNL();
550 
551 	if (WARN_ON(!ieee80211_sdata_running(sdata)))
552 		return;
553 
554 	mutex_lock(&sdata->local->key_mtx);
555 
556 	sdata->crypto_tx_tailroom_needed_cnt = 0;
557 
558 	list_for_each_entry(key, &sdata->key_list, list) {
559 		increment_tailroom_need_count(sdata);
560 		ieee80211_key_enable_hw_accel(key);
561 	}
562 
563 	mutex_unlock(&sdata->local->key_mtx);
564 }
565 
566 void ieee80211_iter_keys(struct ieee80211_hw *hw,
567 			 struct ieee80211_vif *vif,
568 			 void (*iter)(struct ieee80211_hw *hw,
569 				      struct ieee80211_vif *vif,
570 				      struct ieee80211_sta *sta,
571 				      struct ieee80211_key_conf *key,
572 				      void *data),
573 			 void *iter_data)
574 {
575 	struct ieee80211_local *local = hw_to_local(hw);
576 	struct ieee80211_key *key, *tmp;
577 	struct ieee80211_sub_if_data *sdata;
578 
579 	ASSERT_RTNL();
580 
581 	mutex_lock(&local->key_mtx);
582 	if (vif) {
583 		sdata = vif_to_sdata(vif);
584 		list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
585 			iter(hw, &sdata->vif,
586 			     key->sta ? &key->sta->sta : NULL,
587 			     &key->conf, iter_data);
588 	} else {
589 		list_for_each_entry(sdata, &local->interfaces, list)
590 			list_for_each_entry_safe(key, tmp,
591 						 &sdata->key_list, list)
592 				iter(hw, &sdata->vif,
593 				     key->sta ? &key->sta->sta : NULL,
594 				     &key->conf, iter_data);
595 	}
596 	mutex_unlock(&local->key_mtx);
597 }
598 EXPORT_SYMBOL(ieee80211_iter_keys);
599 
600 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
601 				      struct list_head *keys)
602 {
603 	struct ieee80211_key *key, *tmp;
604 
605 	sdata->crypto_tx_tailroom_needed_cnt -=
606 		sdata->crypto_tx_tailroom_pending_dec;
607 	sdata->crypto_tx_tailroom_pending_dec = 0;
608 
609 	ieee80211_debugfs_key_remove_mgmt_default(sdata);
610 
611 	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
612 		ieee80211_key_replace(key->sdata, key->sta,
613 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
614 				key, NULL);
615 		list_add_tail(&key->list, keys);
616 	}
617 
618 	ieee80211_debugfs_key_update_default(sdata);
619 }
620 
621 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
622 			 bool force_synchronize)
623 {
624 	struct ieee80211_local *local = sdata->local;
625 	struct ieee80211_sub_if_data *vlan;
626 	struct ieee80211_key *key, *tmp;
627 	LIST_HEAD(keys);
628 
629 	cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
630 
631 	mutex_lock(&local->key_mtx);
632 
633 	ieee80211_free_keys_iface(sdata, &keys);
634 
635 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
636 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
637 			ieee80211_free_keys_iface(vlan, &keys);
638 	}
639 
640 	if (!list_empty(&keys) || force_synchronize)
641 		synchronize_net();
642 	list_for_each_entry_safe(key, tmp, &keys, list)
643 		__ieee80211_key_destroy(key, false);
644 
645 	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
646 		     sdata->crypto_tx_tailroom_pending_dec);
647 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
648 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
649 			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
650 				     vlan->crypto_tx_tailroom_pending_dec);
651 	}
652 
653 	mutex_unlock(&local->key_mtx);
654 }
655 
656 void ieee80211_free_sta_keys(struct ieee80211_local *local,
657 			     struct sta_info *sta)
658 {
659 	struct ieee80211_key *key;
660 	int i;
661 
662 	mutex_lock(&local->key_mtx);
663 	for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
664 		key = key_mtx_dereference(local, sta->gtk[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 	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
674 		key = key_mtx_dereference(local, sta->ptk[i]);
675 		if (!key)
676 			continue;
677 		ieee80211_key_replace(key->sdata, key->sta,
678 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
679 				key, NULL);
680 		__ieee80211_key_destroy(key, true);
681 	}
682 
683 	mutex_unlock(&local->key_mtx);
684 }
685 
686 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
687 {
688 	struct ieee80211_sub_if_data *sdata;
689 
690 	sdata = container_of(wk, struct ieee80211_sub_if_data,
691 			     dec_tailroom_needed_wk.work);
692 
693 	/*
694 	 * The reason for the delayed tailroom needed decrementing is to
695 	 * make roaming faster: during roaming, all keys are first deleted
696 	 * and then new keys are installed. The first new key causes the
697 	 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
698 	 * the cost of synchronize_net() (which can be slow). Avoid this
699 	 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
700 	 * key removal for a while, so if we roam the value is larger than
701 	 * zero and no 0->1 transition happens.
702 	 *
703 	 * The cost is that if the AP switching was from an AP with keys
704 	 * to one without, we still allocate tailroom while it would no
705 	 * longer be needed. However, in the typical (fast) roaming case
706 	 * within an ESS this usually won't happen.
707 	 */
708 
709 	mutex_lock(&sdata->local->key_mtx);
710 	sdata->crypto_tx_tailroom_needed_cnt -=
711 		sdata->crypto_tx_tailroom_pending_dec;
712 	sdata->crypto_tx_tailroom_pending_dec = 0;
713 	mutex_unlock(&sdata->local->key_mtx);
714 }
715 
716 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
717 				const u8 *replay_ctr, gfp_t gfp)
718 {
719 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
720 
721 	trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
722 
723 	cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
724 }
725 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
726 
727 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
728 			      struct ieee80211_key_seq *seq)
729 {
730 	struct ieee80211_key *key;
731 	u64 pn64;
732 
733 	if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
734 		return;
735 
736 	key = container_of(keyconf, struct ieee80211_key, conf);
737 
738 	switch (key->conf.cipher) {
739 	case WLAN_CIPHER_SUITE_TKIP:
740 		seq->tkip.iv32 = key->u.tkip.tx.iv32;
741 		seq->tkip.iv16 = key->u.tkip.tx.iv16;
742 		break;
743 	case WLAN_CIPHER_SUITE_CCMP:
744 		pn64 = atomic64_read(&key->u.ccmp.tx_pn);
745 		seq->ccmp.pn[5] = pn64;
746 		seq->ccmp.pn[4] = pn64 >> 8;
747 		seq->ccmp.pn[3] = pn64 >> 16;
748 		seq->ccmp.pn[2] = pn64 >> 24;
749 		seq->ccmp.pn[1] = pn64 >> 32;
750 		seq->ccmp.pn[0] = pn64 >> 40;
751 		break;
752 	case WLAN_CIPHER_SUITE_AES_CMAC:
753 		pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
754 		seq->ccmp.pn[5] = pn64;
755 		seq->ccmp.pn[4] = pn64 >> 8;
756 		seq->ccmp.pn[3] = pn64 >> 16;
757 		seq->ccmp.pn[2] = pn64 >> 24;
758 		seq->ccmp.pn[1] = pn64 >> 32;
759 		seq->ccmp.pn[0] = pn64 >> 40;
760 		break;
761 	default:
762 		WARN_ON(1);
763 	}
764 }
765 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
766 
767 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
768 			      int tid, struct ieee80211_key_seq *seq)
769 {
770 	struct ieee80211_key *key;
771 	const u8 *pn;
772 
773 	key = container_of(keyconf, struct ieee80211_key, conf);
774 
775 	switch (key->conf.cipher) {
776 	case WLAN_CIPHER_SUITE_TKIP:
777 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
778 			return;
779 		seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
780 		seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
781 		break;
782 	case WLAN_CIPHER_SUITE_CCMP:
783 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
784 			return;
785 		if (tid < 0)
786 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
787 		else
788 			pn = key->u.ccmp.rx_pn[tid];
789 		memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
790 		break;
791 	case WLAN_CIPHER_SUITE_AES_CMAC:
792 		if (WARN_ON(tid != 0))
793 			return;
794 		pn = key->u.aes_cmac.rx_pn;
795 		memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
796 		break;
797 	}
798 }
799 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
800 
801 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
802 			      struct ieee80211_key_seq *seq)
803 {
804 	struct ieee80211_key *key;
805 	u64 pn64;
806 
807 	key = container_of(keyconf, struct ieee80211_key, conf);
808 
809 	switch (key->conf.cipher) {
810 	case WLAN_CIPHER_SUITE_TKIP:
811 		key->u.tkip.tx.iv32 = seq->tkip.iv32;
812 		key->u.tkip.tx.iv16 = seq->tkip.iv16;
813 		break;
814 	case WLAN_CIPHER_SUITE_CCMP:
815 		pn64 = (u64)seq->ccmp.pn[5] |
816 		       ((u64)seq->ccmp.pn[4] << 8) |
817 		       ((u64)seq->ccmp.pn[3] << 16) |
818 		       ((u64)seq->ccmp.pn[2] << 24) |
819 		       ((u64)seq->ccmp.pn[1] << 32) |
820 		       ((u64)seq->ccmp.pn[0] << 40);
821 		atomic64_set(&key->u.ccmp.tx_pn, pn64);
822 		break;
823 	case WLAN_CIPHER_SUITE_AES_CMAC:
824 		pn64 = (u64)seq->aes_cmac.pn[5] |
825 		       ((u64)seq->aes_cmac.pn[4] << 8) |
826 		       ((u64)seq->aes_cmac.pn[3] << 16) |
827 		       ((u64)seq->aes_cmac.pn[2] << 24) |
828 		       ((u64)seq->aes_cmac.pn[1] << 32) |
829 		       ((u64)seq->aes_cmac.pn[0] << 40);
830 		atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
831 		break;
832 	default:
833 		WARN_ON(1);
834 		break;
835 	}
836 }
837 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
838 
839 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
840 			      int tid, struct ieee80211_key_seq *seq)
841 {
842 	struct ieee80211_key *key;
843 	u8 *pn;
844 
845 	key = container_of(keyconf, struct ieee80211_key, conf);
846 
847 	switch (key->conf.cipher) {
848 	case WLAN_CIPHER_SUITE_TKIP:
849 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
850 			return;
851 		key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
852 		key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
853 		break;
854 	case WLAN_CIPHER_SUITE_CCMP:
855 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
856 			return;
857 		if (tid < 0)
858 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
859 		else
860 			pn = key->u.ccmp.rx_pn[tid];
861 		memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
862 		break;
863 	case WLAN_CIPHER_SUITE_AES_CMAC:
864 		if (WARN_ON(tid != 0))
865 			return;
866 		pn = key->u.aes_cmac.rx_pn;
867 		memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
868 		break;
869 	default:
870 		WARN_ON(1);
871 		break;
872 	}
873 }
874 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
875 
876 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
877 {
878 	struct ieee80211_key *key;
879 
880 	key = container_of(keyconf, struct ieee80211_key, conf);
881 
882 	assert_key_lock(key->local);
883 
884 	/*
885 	 * if key was uploaded, we assume the driver will/has remove(d)
886 	 * it, so adjust bookkeeping accordingly
887 	 */
888 	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
889 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
890 
891 		if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
892 		      (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
893 		      (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
894 			increment_tailroom_need_count(key->sdata);
895 	}
896 
897 	ieee80211_key_free(key, false);
898 }
899 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
900 
901 struct ieee80211_key_conf *
902 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
903 			struct ieee80211_key_conf *keyconf)
904 {
905 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
906 	struct ieee80211_local *local = sdata->local;
907 	struct ieee80211_key *key;
908 	int err;
909 
910 	if (WARN_ON(!local->wowlan))
911 		return ERR_PTR(-EINVAL);
912 
913 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
914 		return ERR_PTR(-EINVAL);
915 
916 	key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
917 				  keyconf->keylen, keyconf->key,
918 				  0, NULL, NULL);
919 	if (IS_ERR(key))
920 		return ERR_CAST(key);
921 
922 	if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
923 		key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
924 
925 	err = ieee80211_key_link(key, sdata, NULL);
926 	if (err)
927 		return ERR_PTR(err);
928 
929 	return &key->conf;
930 }
931 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
932