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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2002-2005, Instant802 Networks, Inc.
4  * Copyright 2005-2006, Devicescape Software, Inc.
5  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
6  * Copyright 2007-2008	Johannes Berg <johannes@sipsolutions.net>
7  * Copyright 2013-2014  Intel Mobile Communications GmbH
8  * Copyright 2015-2017	Intel Deutschland GmbH
9  * Copyright 2018-2020  Intel Corporation
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 <crypto/algapi.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 #include "aes_gmac.h"
28 #include "aes_gcm.h"
29 
30 
31 /**
32  * DOC: Key handling basics
33  *
34  * Key handling in mac80211 is done based on per-interface (sub_if_data)
35  * keys and per-station keys. Since each station belongs to an interface,
36  * each station key also belongs to that interface.
37  *
38  * Hardware acceleration is done on a best-effort basis for algorithms
39  * that are implemented in software,  for each key the hardware is asked
40  * to enable that key for offloading but if it cannot do that the key is
41  * simply kept for software encryption (unless it is for an algorithm
42  * that isn't implemented in software).
43  * There is currently no way of knowing whether a key is handled in SW
44  * or HW except by looking into debugfs.
45  *
46  * All key management is internally protected by a mutex. Within all
47  * other parts of mac80211, key references are, just as STA structure
48  * references, protected by RCU. Note, however, that some things are
49  * unprotected, namely the key->sta dereferences within the hardware
50  * acceleration functions. This means that sta_info_destroy() must
51  * remove the key which waits for an RCU grace period.
52  */
53 
54 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
55 
assert_key_lock(struct ieee80211_local * local)56 static void assert_key_lock(struct ieee80211_local *local)
57 {
58 	lockdep_assert_held(&local->key_mtx);
59 }
60 
61 static void
update_vlan_tailroom_need_count(struct ieee80211_sub_if_data * sdata,int delta)62 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
63 {
64 	struct ieee80211_sub_if_data *vlan;
65 
66 	if (sdata->vif.type != NL80211_IFTYPE_AP)
67 		return;
68 
69 	/* crypto_tx_tailroom_needed_cnt is protected by this */
70 	assert_key_lock(sdata->local);
71 
72 	rcu_read_lock();
73 
74 	list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
75 		vlan->crypto_tx_tailroom_needed_cnt += delta;
76 
77 	rcu_read_unlock();
78 }
79 
increment_tailroom_need_count(struct ieee80211_sub_if_data * sdata)80 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
81 {
82 	/*
83 	 * When this count is zero, SKB resizing for allocating tailroom
84 	 * for IV or MMIC is skipped. But, this check has created two race
85 	 * cases in xmit path while transiting from zero count to one:
86 	 *
87 	 * 1. SKB resize was skipped because no key was added but just before
88 	 * the xmit key is added and SW encryption kicks off.
89 	 *
90 	 * 2. SKB resize was skipped because all the keys were hw planted but
91 	 * just before xmit one of the key is deleted and SW encryption kicks
92 	 * off.
93 	 *
94 	 * In both the above case SW encryption will find not enough space for
95 	 * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
96 	 *
97 	 * Solution has been explained at
98 	 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
99 	 */
100 
101 	assert_key_lock(sdata->local);
102 
103 	update_vlan_tailroom_need_count(sdata, 1);
104 
105 	if (!sdata->crypto_tx_tailroom_needed_cnt++) {
106 		/*
107 		 * Flush all XMIT packets currently using HW encryption or no
108 		 * encryption at all if the count transition is from 0 -> 1.
109 		 */
110 		synchronize_net();
111 	}
112 }
113 
decrease_tailroom_need_count(struct ieee80211_sub_if_data * sdata,int delta)114 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
115 					 int delta)
116 {
117 	assert_key_lock(sdata->local);
118 
119 	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
120 
121 	update_vlan_tailroom_need_count(sdata, -delta);
122 	sdata->crypto_tx_tailroom_needed_cnt -= delta;
123 }
124 
ieee80211_key_enable_hw_accel(struct ieee80211_key * key)125 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
126 {
127 	struct ieee80211_sub_if_data *sdata = key->sdata;
128 	struct sta_info *sta;
129 	int ret = -EOPNOTSUPP;
130 
131 	might_sleep();
132 
133 	if (key->flags & KEY_FLAG_TAINTED) {
134 		/* If we get here, it's during resume and the key is
135 		 * tainted so shouldn't be used/programmed any more.
136 		 * However, its flags may still indicate that it was
137 		 * programmed into the device (since we're in resume)
138 		 * so clear that flag now to avoid trying to remove
139 		 * it again later.
140 		 */
141 		if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE &&
142 		    !(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
143 					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
144 					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
145 			increment_tailroom_need_count(sdata);
146 
147 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
148 		return -EINVAL;
149 	}
150 
151 	if (!key->local->ops->set_key)
152 		goto out_unsupported;
153 
154 	assert_key_lock(key->local);
155 
156 	sta = key->sta;
157 
158 	/*
159 	 * If this is a per-STA GTK, check if it
160 	 * is supported; if not, return.
161 	 */
162 	if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
163 	    !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
164 		goto out_unsupported;
165 
166 	if (sta && !sta->uploaded)
167 		goto out_unsupported;
168 
169 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
170 		/*
171 		 * The driver doesn't know anything about VLAN interfaces.
172 		 * Hence, don't send GTKs for VLAN interfaces to the driver.
173 		 */
174 		if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
175 			ret = 1;
176 			goto out_unsupported;
177 		}
178 	}
179 
180 	ret = drv_set_key(key->local, SET_KEY, sdata,
181 			  sta ? &sta->sta : NULL, &key->conf);
182 
183 	if (!ret) {
184 		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
185 
186 		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
187 					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
188 					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
189 			decrease_tailroom_need_count(sdata, 1);
190 
191 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
192 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
193 
194 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
195 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
196 
197 		return 0;
198 	}
199 
200 	if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
201 		sdata_err(sdata,
202 			  "failed to set key (%d, %pM) to hardware (%d)\n",
203 			  key->conf.keyidx,
204 			  sta ? sta->sta.addr : bcast_addr, ret);
205 
206  out_unsupported:
207 	switch (key->conf.cipher) {
208 	case WLAN_CIPHER_SUITE_WEP40:
209 	case WLAN_CIPHER_SUITE_WEP104:
210 	case WLAN_CIPHER_SUITE_TKIP:
211 	case WLAN_CIPHER_SUITE_CCMP:
212 	case WLAN_CIPHER_SUITE_CCMP_256:
213 	case WLAN_CIPHER_SUITE_AES_CMAC:
214 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
215 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
216 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
217 	case WLAN_CIPHER_SUITE_GCMP:
218 	case WLAN_CIPHER_SUITE_GCMP_256:
219 		/* all of these we can do in software - if driver can */
220 		if (ret == 1)
221 			return 0;
222 		if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
223 			return -EINVAL;
224 		return 0;
225 	default:
226 		return -EINVAL;
227 	}
228 }
229 
ieee80211_key_disable_hw_accel(struct ieee80211_key * key)230 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
231 {
232 	struct ieee80211_sub_if_data *sdata;
233 	struct sta_info *sta;
234 	int ret;
235 
236 	might_sleep();
237 
238 	if (!key || !key->local->ops->set_key)
239 		return;
240 
241 	assert_key_lock(key->local);
242 
243 	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
244 		return;
245 
246 	sta = key->sta;
247 	sdata = key->sdata;
248 
249 	if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
250 				 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
251 				 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
252 		increment_tailroom_need_count(sdata);
253 
254 	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
255 	ret = drv_set_key(key->local, DISABLE_KEY, sdata,
256 			  sta ? &sta->sta : NULL, &key->conf);
257 
258 	if (ret)
259 		sdata_err(sdata,
260 			  "failed to remove key (%d, %pM) from hardware (%d)\n",
261 			  key->conf.keyidx,
262 			  sta ? sta->sta.addr : bcast_addr, ret);
263 }
264 
_ieee80211_set_tx_key(struct ieee80211_key * key,bool force)265 static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force)
266 {
267 	struct sta_info *sta = key->sta;
268 	struct ieee80211_local *local = key->local;
269 
270 	assert_key_lock(local);
271 
272 	set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION);
273 
274 	sta->ptk_idx = key->conf.keyidx;
275 
276 	if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
277 		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
278 	ieee80211_check_fast_xmit(sta);
279 
280 	return 0;
281 }
282 
ieee80211_set_tx_key(struct ieee80211_key * key)283 int ieee80211_set_tx_key(struct ieee80211_key *key)
284 {
285 	return _ieee80211_set_tx_key(key, false);
286 }
287 
ieee80211_pairwise_rekey(struct ieee80211_key * old,struct ieee80211_key * new)288 static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
289 				     struct ieee80211_key *new)
290 {
291 	struct ieee80211_local *local = new->local;
292 	struct sta_info *sta = new->sta;
293 	int i;
294 
295 	assert_key_lock(local);
296 
297 	if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) {
298 		/* Extended Key ID key install, initial one or rekey */
299 
300 		if (sta->ptk_idx != INVALID_PTK_KEYIDX &&
301 		    !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) {
302 			/* Aggregation Sessions with Extended Key ID must not
303 			 * mix MPDUs with different keyIDs within one A-MPDU.
304 			 * Tear down running Tx aggregation sessions and block
305 			 * new Rx/Tx aggregation requests during rekey to
306 			 * ensure there are no A-MPDUs when the driver is not
307 			 * supporting A-MPDU key borders. (Blocking Tx only
308 			 * would be sufficient but WLAN_STA_BLOCK_BA gets the
309 			 * job done for the few ms we need it.)
310 			 */
311 			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
312 			mutex_lock(&sta->ampdu_mlme.mtx);
313 			for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
314 				___ieee80211_stop_tx_ba_session(sta, i,
315 								AGG_STOP_LOCAL_REQUEST);
316 			mutex_unlock(&sta->ampdu_mlme.mtx);
317 		}
318 	} else if (old) {
319 		/* Rekey without Extended Key ID.
320 		 * Aggregation sessions are OK when running on SW crypto.
321 		 * A broken remote STA may cause issues not observed with HW
322 		 * crypto, though.
323 		 */
324 		if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
325 			return;
326 
327 		/* Stop Tx till we are on the new key */
328 		old->flags |= KEY_FLAG_TAINTED;
329 		ieee80211_clear_fast_xmit(sta);
330 		if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
331 			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
332 			ieee80211_sta_tear_down_BA_sessions(sta,
333 							    AGG_STOP_LOCAL_REQUEST);
334 		}
335 		if (!wiphy_ext_feature_isset(local->hw.wiphy,
336 					     NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) {
337 			pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.",
338 					    sta->sta.addr);
339 			/* Flushing the driver queues *may* help prevent
340 			 * the clear text leaks and freezes.
341 			 */
342 			ieee80211_flush_queues(local, old->sdata, false);
343 		}
344 	}
345 }
346 
__ieee80211_set_default_key(struct ieee80211_sub_if_data * sdata,int idx,bool uni,bool multi)347 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
348 					int idx, bool uni, bool multi)
349 {
350 	struct ieee80211_key *key = NULL;
351 
352 	assert_key_lock(sdata->local);
353 
354 	if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
355 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
356 
357 	if (uni) {
358 		rcu_assign_pointer(sdata->default_unicast_key, key);
359 		ieee80211_check_fast_xmit_iface(sdata);
360 		if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
361 			drv_set_default_unicast_key(sdata->local, sdata, idx);
362 	}
363 
364 	if (multi)
365 		rcu_assign_pointer(sdata->default_multicast_key, key);
366 
367 	ieee80211_debugfs_key_update_default(sdata);
368 }
369 
ieee80211_set_default_key(struct ieee80211_sub_if_data * sdata,int idx,bool uni,bool multi)370 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
371 			       bool uni, bool multi)
372 {
373 	mutex_lock(&sdata->local->key_mtx);
374 	__ieee80211_set_default_key(sdata, idx, uni, multi);
375 	mutex_unlock(&sdata->local->key_mtx);
376 }
377 
378 static void
__ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data * sdata,int idx)379 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
380 {
381 	struct ieee80211_key *key = NULL;
382 
383 	assert_key_lock(sdata->local);
384 
385 	if (idx >= NUM_DEFAULT_KEYS &&
386 	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
387 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
388 
389 	rcu_assign_pointer(sdata->default_mgmt_key, key);
390 
391 	ieee80211_debugfs_key_update_default(sdata);
392 }
393 
ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data * sdata,int idx)394 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
395 				    int idx)
396 {
397 	mutex_lock(&sdata->local->key_mtx);
398 	__ieee80211_set_default_mgmt_key(sdata, idx);
399 	mutex_unlock(&sdata->local->key_mtx);
400 }
401 
ieee80211_key_replace(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,bool pairwise,struct ieee80211_key * old,struct ieee80211_key * new)402 static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
403 				  struct sta_info *sta,
404 				  bool pairwise,
405 				  struct ieee80211_key *old,
406 				  struct ieee80211_key *new)
407 {
408 	int idx;
409 	int ret = 0;
410 	bool defunikey, defmultikey, defmgmtkey;
411 
412 	/* caller must provide at least one old/new */
413 	if (WARN_ON(!new && !old))
414 		return 0;
415 
416 	if (new)
417 		list_add_tail_rcu(&new->list, &sdata->key_list);
418 
419 	WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
420 
421 	if (new && sta && pairwise) {
422 		/* Unicast rekey needs special handling. With Extended Key ID
423 		 * old is still NULL for the first rekey.
424 		 */
425 		ieee80211_pairwise_rekey(old, new);
426 	}
427 
428 	if (old) {
429 		idx = old->conf.keyidx;
430 
431 		if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
432 			ieee80211_key_disable_hw_accel(old);
433 
434 			if (new)
435 				ret = ieee80211_key_enable_hw_accel(new);
436 		}
437 	} else {
438 		/* new must be provided in case old is not */
439 		idx = new->conf.keyidx;
440 		if (!new->local->wowlan)
441 			ret = ieee80211_key_enable_hw_accel(new);
442 	}
443 
444 	if (ret)
445 		return ret;
446 
447 	if (sta) {
448 		if (pairwise) {
449 			rcu_assign_pointer(sta->ptk[idx], new);
450 			if (new &&
451 			    !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX))
452 				_ieee80211_set_tx_key(new, true);
453 		} else {
454 			rcu_assign_pointer(sta->gtk[idx], new);
455 		}
456 		/* Only needed for transition from no key -> key.
457 		 * Still triggers unnecessary when using Extended Key ID
458 		 * and installing the second key ID the first time.
459 		 */
460 		if (new && !old)
461 			ieee80211_check_fast_rx(sta);
462 	} else {
463 		defunikey = old &&
464 			old == key_mtx_dereference(sdata->local,
465 						sdata->default_unicast_key);
466 		defmultikey = old &&
467 			old == key_mtx_dereference(sdata->local,
468 						sdata->default_multicast_key);
469 		defmgmtkey = old &&
470 			old == key_mtx_dereference(sdata->local,
471 						sdata->default_mgmt_key);
472 
473 		if (defunikey && !new)
474 			__ieee80211_set_default_key(sdata, -1, true, false);
475 		if (defmultikey && !new)
476 			__ieee80211_set_default_key(sdata, -1, false, true);
477 		if (defmgmtkey && !new)
478 			__ieee80211_set_default_mgmt_key(sdata, -1);
479 
480 		rcu_assign_pointer(sdata->keys[idx], new);
481 		if (defunikey && new)
482 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
483 						    true, false);
484 		if (defmultikey && new)
485 			__ieee80211_set_default_key(sdata, new->conf.keyidx,
486 						    false, true);
487 		if (defmgmtkey && new)
488 			__ieee80211_set_default_mgmt_key(sdata,
489 							 new->conf.keyidx);
490 	}
491 
492 	if (old)
493 		list_del_rcu(&old->list);
494 
495 	return 0;
496 }
497 
498 struct ieee80211_key *
ieee80211_key_alloc(u32 cipher,int idx,size_t key_len,const u8 * key_data,size_t seq_len,const u8 * seq,const struct ieee80211_cipher_scheme * cs)499 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
500 		    const u8 *key_data,
501 		    size_t seq_len, const u8 *seq,
502 		    const struct ieee80211_cipher_scheme *cs)
503 {
504 	struct ieee80211_key *key;
505 	int i, j, err;
506 
507 	if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
508 		return ERR_PTR(-EINVAL);
509 
510 	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
511 	if (!key)
512 		return ERR_PTR(-ENOMEM);
513 
514 	/*
515 	 * Default to software encryption; we'll later upload the
516 	 * key to the hardware if possible.
517 	 */
518 	key->conf.flags = 0;
519 	key->flags = 0;
520 
521 	key->conf.cipher = cipher;
522 	key->conf.keyidx = idx;
523 	key->conf.keylen = key_len;
524 	switch (cipher) {
525 	case WLAN_CIPHER_SUITE_WEP40:
526 	case WLAN_CIPHER_SUITE_WEP104:
527 		key->conf.iv_len = IEEE80211_WEP_IV_LEN;
528 		key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
529 		break;
530 	case WLAN_CIPHER_SUITE_TKIP:
531 		key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
532 		key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
533 		if (seq) {
534 			for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
535 				key->u.tkip.rx[i].iv32 =
536 					get_unaligned_le32(&seq[2]);
537 				key->u.tkip.rx[i].iv16 =
538 					get_unaligned_le16(seq);
539 			}
540 		}
541 		spin_lock_init(&key->u.tkip.txlock);
542 		break;
543 	case WLAN_CIPHER_SUITE_CCMP:
544 		key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
545 		key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
546 		if (seq) {
547 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
548 				for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
549 					key->u.ccmp.rx_pn[i][j] =
550 						seq[IEEE80211_CCMP_PN_LEN - j - 1];
551 		}
552 		/*
553 		 * Initialize AES key state here as an optimization so that
554 		 * it does not need to be initialized for every packet.
555 		 */
556 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
557 			key_data, key_len, IEEE80211_CCMP_MIC_LEN);
558 		if (IS_ERR(key->u.ccmp.tfm)) {
559 			err = PTR_ERR(key->u.ccmp.tfm);
560 			kfree(key);
561 			return ERR_PTR(err);
562 		}
563 		break;
564 	case WLAN_CIPHER_SUITE_CCMP_256:
565 		key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
566 		key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
567 		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
568 			for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
569 				key->u.ccmp.rx_pn[i][j] =
570 					seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
571 		/* Initialize AES key state here as an optimization so that
572 		 * it does not need to be initialized for every packet.
573 		 */
574 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
575 			key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
576 		if (IS_ERR(key->u.ccmp.tfm)) {
577 			err = PTR_ERR(key->u.ccmp.tfm);
578 			kfree(key);
579 			return ERR_PTR(err);
580 		}
581 		break;
582 	case WLAN_CIPHER_SUITE_AES_CMAC:
583 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
584 		key->conf.iv_len = 0;
585 		if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
586 			key->conf.icv_len = sizeof(struct ieee80211_mmie);
587 		else
588 			key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
589 		if (seq)
590 			for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
591 				key->u.aes_cmac.rx_pn[j] =
592 					seq[IEEE80211_CMAC_PN_LEN - j - 1];
593 		/*
594 		 * Initialize AES key state here as an optimization so that
595 		 * it does not need to be initialized for every packet.
596 		 */
597 		key->u.aes_cmac.tfm =
598 			ieee80211_aes_cmac_key_setup(key_data, key_len);
599 		if (IS_ERR(key->u.aes_cmac.tfm)) {
600 			err = PTR_ERR(key->u.aes_cmac.tfm);
601 			kfree(key);
602 			return ERR_PTR(err);
603 		}
604 		break;
605 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
606 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
607 		key->conf.iv_len = 0;
608 		key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
609 		if (seq)
610 			for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
611 				key->u.aes_gmac.rx_pn[j] =
612 					seq[IEEE80211_GMAC_PN_LEN - j - 1];
613 		/* Initialize AES key state here as an optimization so that
614 		 * it does not need to be initialized for every packet.
615 		 */
616 		key->u.aes_gmac.tfm =
617 			ieee80211_aes_gmac_key_setup(key_data, key_len);
618 		if (IS_ERR(key->u.aes_gmac.tfm)) {
619 			err = PTR_ERR(key->u.aes_gmac.tfm);
620 			kfree(key);
621 			return ERR_PTR(err);
622 		}
623 		break;
624 	case WLAN_CIPHER_SUITE_GCMP:
625 	case WLAN_CIPHER_SUITE_GCMP_256:
626 		key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
627 		key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
628 		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
629 			for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
630 				key->u.gcmp.rx_pn[i][j] =
631 					seq[IEEE80211_GCMP_PN_LEN - j - 1];
632 		/* Initialize AES key state here as an optimization so that
633 		 * it does not need to be initialized for every packet.
634 		 */
635 		key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
636 								      key_len);
637 		if (IS_ERR(key->u.gcmp.tfm)) {
638 			err = PTR_ERR(key->u.gcmp.tfm);
639 			kfree(key);
640 			return ERR_PTR(err);
641 		}
642 		break;
643 	default:
644 		if (cs) {
645 			if (seq_len && seq_len != cs->pn_len) {
646 				kfree(key);
647 				return ERR_PTR(-EINVAL);
648 			}
649 
650 			key->conf.iv_len = cs->hdr_len;
651 			key->conf.icv_len = cs->mic_len;
652 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
653 				for (j = 0; j < seq_len; j++)
654 					key->u.gen.rx_pn[i][j] =
655 							seq[seq_len - j - 1];
656 			key->flags |= KEY_FLAG_CIPHER_SCHEME;
657 		}
658 	}
659 	memcpy(key->conf.key, key_data, key_len);
660 	INIT_LIST_HEAD(&key->list);
661 
662 	return key;
663 }
664 
ieee80211_key_free_common(struct ieee80211_key * key)665 static void ieee80211_key_free_common(struct ieee80211_key *key)
666 {
667 	switch (key->conf.cipher) {
668 	case WLAN_CIPHER_SUITE_CCMP:
669 	case WLAN_CIPHER_SUITE_CCMP_256:
670 		ieee80211_aes_key_free(key->u.ccmp.tfm);
671 		break;
672 	case WLAN_CIPHER_SUITE_AES_CMAC:
673 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
674 		ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
675 		break;
676 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
677 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
678 		ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
679 		break;
680 	case WLAN_CIPHER_SUITE_GCMP:
681 	case WLAN_CIPHER_SUITE_GCMP_256:
682 		ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
683 		break;
684 	}
685 	kzfree(key);
686 }
687 
__ieee80211_key_destroy(struct ieee80211_key * key,bool delay_tailroom)688 static void __ieee80211_key_destroy(struct ieee80211_key *key,
689 				    bool delay_tailroom)
690 {
691 	if (key->local) {
692 		struct ieee80211_sub_if_data *sdata = key->sdata;
693 
694 		ieee80211_debugfs_key_remove(key);
695 
696 		if (delay_tailroom) {
697 			/* see ieee80211_delayed_tailroom_dec */
698 			sdata->crypto_tx_tailroom_pending_dec++;
699 			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
700 					      HZ/2);
701 		} else {
702 			decrease_tailroom_need_count(sdata, 1);
703 		}
704 	}
705 
706 	ieee80211_key_free_common(key);
707 }
708 
ieee80211_key_destroy(struct ieee80211_key * key,bool delay_tailroom)709 static void ieee80211_key_destroy(struct ieee80211_key *key,
710 				  bool delay_tailroom)
711 {
712 	if (!key)
713 		return;
714 
715 	/*
716 	 * Synchronize so the TX path and rcu key iterators
717 	 * can no longer be using this key before we free/remove it.
718 	 */
719 	synchronize_net();
720 
721 	__ieee80211_key_destroy(key, delay_tailroom);
722 }
723 
ieee80211_key_free_unused(struct ieee80211_key * key)724 void ieee80211_key_free_unused(struct ieee80211_key *key)
725 {
726 	WARN_ON(key->sdata || key->local);
727 	ieee80211_key_free_common(key);
728 }
729 
ieee80211_key_identical(struct ieee80211_sub_if_data * sdata,struct ieee80211_key * old,struct ieee80211_key * new)730 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
731 				    struct ieee80211_key *old,
732 				    struct ieee80211_key *new)
733 {
734 	u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
735 	u8 *tk_old, *tk_new;
736 
737 	if (!old || new->conf.keylen != old->conf.keylen)
738 		return false;
739 
740 	tk_old = old->conf.key;
741 	tk_new = new->conf.key;
742 
743 	/*
744 	 * In station mode, don't compare the TX MIC key, as it's never used
745 	 * and offloaded rekeying may not care to send it to the host. This
746 	 * is the case in iwlwifi, for example.
747 	 */
748 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
749 	    new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
750 	    new->conf.keylen == WLAN_KEY_LEN_TKIP &&
751 	    !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
752 		memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
753 		memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
754 		memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
755 		memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
756 		tk_old = tkip_old;
757 		tk_new = tkip_new;
758 	}
759 
760 	return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
761 }
762 
ieee80211_key_link(struct ieee80211_key * key,struct ieee80211_sub_if_data * sdata,struct sta_info * sta)763 int ieee80211_key_link(struct ieee80211_key *key,
764 		       struct ieee80211_sub_if_data *sdata,
765 		       struct sta_info *sta)
766 {
767 	static atomic_t key_color = ATOMIC_INIT(0);
768 	struct ieee80211_key *old_key;
769 	int idx = key->conf.keyidx;
770 	bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
771 	/*
772 	 * We want to delay tailroom updates only for station - in that
773 	 * case it helps roaming speed, but in other cases it hurts and
774 	 * can cause warnings to appear.
775 	 */
776 	bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
777 	int ret = -EOPNOTSUPP;
778 
779 	mutex_lock(&sdata->local->key_mtx);
780 
781 	if (sta && pairwise) {
782 		struct ieee80211_key *alt_key;
783 
784 		old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
785 		alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]);
786 
787 		/* The rekey code assumes that the old and new key are using
788 		 * the same cipher. Enforce the assumption for pairwise keys.
789 		 */
790 		if ((alt_key && alt_key->conf.cipher != key->conf.cipher) ||
791 		    (old_key && old_key->conf.cipher != key->conf.cipher))
792 			goto out;
793 	} else if (sta) {
794 		old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
795 	} else {
796 		old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
797 	}
798 
799 	/* Non-pairwise keys must also not switch the cipher on rekey */
800 	if (!pairwise) {
801 		if (old_key && old_key->conf.cipher != key->conf.cipher)
802 			goto out;
803 	}
804 
805 	/*
806 	 * Silently accept key re-installation without really installing the
807 	 * new version of the key to avoid nonce reuse or replay issues.
808 	 */
809 	if (ieee80211_key_identical(sdata, old_key, key)) {
810 		ieee80211_key_free_unused(key);
811 		ret = 0;
812 		goto out;
813 	}
814 
815 	key->local = sdata->local;
816 	key->sdata = sdata;
817 	key->sta = sta;
818 
819 	/*
820 	 * Assign a unique ID to every key so we can easily prevent mixed
821 	 * key and fragment cache attacks.
822 	 */
823 	key->color = atomic_inc_return(&key_color);
824 
825 	increment_tailroom_need_count(sdata);
826 
827 	ret = ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
828 
829 	if (!ret) {
830 		ieee80211_debugfs_key_add(key);
831 		ieee80211_key_destroy(old_key, delay_tailroom);
832 	} else {
833 		ieee80211_key_free(key, delay_tailroom);
834 	}
835 
836  out:
837 	mutex_unlock(&sdata->local->key_mtx);
838 
839 	return ret;
840 }
841 
ieee80211_key_free(struct ieee80211_key * key,bool delay_tailroom)842 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
843 {
844 	if (!key)
845 		return;
846 
847 	/*
848 	 * Replace key with nothingness if it was ever used.
849 	 */
850 	if (key->sdata)
851 		ieee80211_key_replace(key->sdata, key->sta,
852 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
853 				key, NULL);
854 	ieee80211_key_destroy(key, delay_tailroom);
855 }
856 
ieee80211_reenable_keys(struct ieee80211_sub_if_data * sdata)857 void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata)
858 {
859 	struct ieee80211_key *key;
860 	struct ieee80211_sub_if_data *vlan;
861 
862 	ASSERT_RTNL();
863 
864 	mutex_lock(&sdata->local->key_mtx);
865 
866 	sdata->crypto_tx_tailroom_needed_cnt = 0;
867 	sdata->crypto_tx_tailroom_pending_dec = 0;
868 
869 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
870 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
871 			vlan->crypto_tx_tailroom_needed_cnt = 0;
872 			vlan->crypto_tx_tailroom_pending_dec = 0;
873 		}
874 	}
875 
876 	if (ieee80211_sdata_running(sdata)) {
877 		list_for_each_entry(key, &sdata->key_list, list) {
878 			increment_tailroom_need_count(sdata);
879 			ieee80211_key_enable_hw_accel(key);
880 		}
881 	}
882 
883 	mutex_unlock(&sdata->local->key_mtx);
884 }
885 
ieee80211_iter_keys(struct ieee80211_hw * hw,struct ieee80211_vif * vif,void (* iter)(struct ieee80211_hw * hw,struct ieee80211_vif * vif,struct ieee80211_sta * sta,struct ieee80211_key_conf * key,void * data),void * iter_data)886 void ieee80211_iter_keys(struct ieee80211_hw *hw,
887 			 struct ieee80211_vif *vif,
888 			 void (*iter)(struct ieee80211_hw *hw,
889 				      struct ieee80211_vif *vif,
890 				      struct ieee80211_sta *sta,
891 				      struct ieee80211_key_conf *key,
892 				      void *data),
893 			 void *iter_data)
894 {
895 	struct ieee80211_local *local = hw_to_local(hw);
896 	struct ieee80211_key *key, *tmp;
897 	struct ieee80211_sub_if_data *sdata;
898 
899 	ASSERT_RTNL();
900 
901 	mutex_lock(&local->key_mtx);
902 	if (vif) {
903 		sdata = vif_to_sdata(vif);
904 		list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
905 			iter(hw, &sdata->vif,
906 			     key->sta ? &key->sta->sta : NULL,
907 			     &key->conf, iter_data);
908 	} else {
909 		list_for_each_entry(sdata, &local->interfaces, list)
910 			list_for_each_entry_safe(key, tmp,
911 						 &sdata->key_list, list)
912 				iter(hw, &sdata->vif,
913 				     key->sta ? &key->sta->sta : NULL,
914 				     &key->conf, iter_data);
915 	}
916 	mutex_unlock(&local->key_mtx);
917 }
918 EXPORT_SYMBOL(ieee80211_iter_keys);
919 
920 static void
_ieee80211_iter_keys_rcu(struct ieee80211_hw * hw,struct ieee80211_sub_if_data * sdata,void (* iter)(struct ieee80211_hw * hw,struct ieee80211_vif * vif,struct ieee80211_sta * sta,struct ieee80211_key_conf * key,void * data),void * iter_data)921 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
922 			 struct ieee80211_sub_if_data *sdata,
923 			 void (*iter)(struct ieee80211_hw *hw,
924 				      struct ieee80211_vif *vif,
925 				      struct ieee80211_sta *sta,
926 				      struct ieee80211_key_conf *key,
927 				      void *data),
928 			 void *iter_data)
929 {
930 	struct ieee80211_key *key;
931 
932 	list_for_each_entry_rcu(key, &sdata->key_list, list) {
933 		/* skip keys of station in removal process */
934 		if (key->sta && key->sta->removed)
935 			continue;
936 		if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
937 			continue;
938 
939 		iter(hw, &sdata->vif,
940 		     key->sta ? &key->sta->sta : NULL,
941 		     &key->conf, iter_data);
942 	}
943 }
944 
ieee80211_iter_keys_rcu(struct ieee80211_hw * hw,struct ieee80211_vif * vif,void (* iter)(struct ieee80211_hw * hw,struct ieee80211_vif * vif,struct ieee80211_sta * sta,struct ieee80211_key_conf * key,void * data),void * iter_data)945 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
946 			     struct ieee80211_vif *vif,
947 			     void (*iter)(struct ieee80211_hw *hw,
948 					  struct ieee80211_vif *vif,
949 					  struct ieee80211_sta *sta,
950 					  struct ieee80211_key_conf *key,
951 					  void *data),
952 			     void *iter_data)
953 {
954 	struct ieee80211_local *local = hw_to_local(hw);
955 	struct ieee80211_sub_if_data *sdata;
956 
957 	if (vif) {
958 		sdata = vif_to_sdata(vif);
959 		_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
960 	} else {
961 		list_for_each_entry_rcu(sdata, &local->interfaces, list)
962 			_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
963 	}
964 }
965 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
966 
ieee80211_free_keys_iface(struct ieee80211_sub_if_data * sdata,struct list_head * keys)967 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
968 				      struct list_head *keys)
969 {
970 	struct ieee80211_key *key, *tmp;
971 
972 	decrease_tailroom_need_count(sdata,
973 				     sdata->crypto_tx_tailroom_pending_dec);
974 	sdata->crypto_tx_tailroom_pending_dec = 0;
975 
976 	ieee80211_debugfs_key_remove_mgmt_default(sdata);
977 
978 	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
979 		ieee80211_key_replace(key->sdata, key->sta,
980 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
981 				key, NULL);
982 		list_add_tail(&key->list, keys);
983 	}
984 
985 	ieee80211_debugfs_key_update_default(sdata);
986 }
987 
ieee80211_free_keys(struct ieee80211_sub_if_data * sdata,bool force_synchronize)988 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
989 			 bool force_synchronize)
990 {
991 	struct ieee80211_local *local = sdata->local;
992 	struct ieee80211_sub_if_data *vlan;
993 	struct ieee80211_sub_if_data *master;
994 	struct ieee80211_key *key, *tmp;
995 	LIST_HEAD(keys);
996 
997 	cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
998 
999 	mutex_lock(&local->key_mtx);
1000 
1001 	ieee80211_free_keys_iface(sdata, &keys);
1002 
1003 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
1004 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1005 			ieee80211_free_keys_iface(vlan, &keys);
1006 	}
1007 
1008 	if (!list_empty(&keys) || force_synchronize)
1009 		synchronize_net();
1010 	list_for_each_entry_safe(key, tmp, &keys, list)
1011 		__ieee80211_key_destroy(key, false);
1012 
1013 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1014 		if (sdata->bss) {
1015 			master = container_of(sdata->bss,
1016 					      struct ieee80211_sub_if_data,
1017 					      u.ap);
1018 
1019 			WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
1020 				     master->crypto_tx_tailroom_needed_cnt);
1021 		}
1022 	} else {
1023 		WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
1024 			     sdata->crypto_tx_tailroom_pending_dec);
1025 	}
1026 
1027 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
1028 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1029 			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
1030 				     vlan->crypto_tx_tailroom_pending_dec);
1031 	}
1032 
1033 	mutex_unlock(&local->key_mtx);
1034 }
1035 
ieee80211_free_sta_keys(struct ieee80211_local * local,struct sta_info * sta)1036 void ieee80211_free_sta_keys(struct ieee80211_local *local,
1037 			     struct sta_info *sta)
1038 {
1039 	struct ieee80211_key *key;
1040 	int i;
1041 
1042 	mutex_lock(&local->key_mtx);
1043 	for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
1044 		key = key_mtx_dereference(local, sta->gtk[i]);
1045 		if (!key)
1046 			continue;
1047 		ieee80211_key_replace(key->sdata, key->sta,
1048 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1049 				key, NULL);
1050 		__ieee80211_key_destroy(key, key->sdata->vif.type ==
1051 					NL80211_IFTYPE_STATION);
1052 	}
1053 
1054 	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1055 		key = key_mtx_dereference(local, sta->ptk[i]);
1056 		if (!key)
1057 			continue;
1058 		ieee80211_key_replace(key->sdata, key->sta,
1059 				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1060 				key, NULL);
1061 		__ieee80211_key_destroy(key, key->sdata->vif.type ==
1062 					NL80211_IFTYPE_STATION);
1063 	}
1064 
1065 	mutex_unlock(&local->key_mtx);
1066 }
1067 
ieee80211_delayed_tailroom_dec(struct work_struct * wk)1068 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
1069 {
1070 	struct ieee80211_sub_if_data *sdata;
1071 
1072 	sdata = container_of(wk, struct ieee80211_sub_if_data,
1073 			     dec_tailroom_needed_wk.work);
1074 
1075 	/*
1076 	 * The reason for the delayed tailroom needed decrementing is to
1077 	 * make roaming faster: during roaming, all keys are first deleted
1078 	 * and then new keys are installed. The first new key causes the
1079 	 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
1080 	 * the cost of synchronize_net() (which can be slow). Avoid this
1081 	 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
1082 	 * key removal for a while, so if we roam the value is larger than
1083 	 * zero and no 0->1 transition happens.
1084 	 *
1085 	 * The cost is that if the AP switching was from an AP with keys
1086 	 * to one without, we still allocate tailroom while it would no
1087 	 * longer be needed. However, in the typical (fast) roaming case
1088 	 * within an ESS this usually won't happen.
1089 	 */
1090 
1091 	mutex_lock(&sdata->local->key_mtx);
1092 	decrease_tailroom_need_count(sdata,
1093 				     sdata->crypto_tx_tailroom_pending_dec);
1094 	sdata->crypto_tx_tailroom_pending_dec = 0;
1095 	mutex_unlock(&sdata->local->key_mtx);
1096 }
1097 
ieee80211_gtk_rekey_notify(struct ieee80211_vif * vif,const u8 * bssid,const u8 * replay_ctr,gfp_t gfp)1098 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
1099 				const u8 *replay_ctr, gfp_t gfp)
1100 {
1101 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1102 
1103 	trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
1104 
1105 	cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
1106 }
1107 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
1108 
ieee80211_get_key_rx_seq(struct ieee80211_key_conf * keyconf,int tid,struct ieee80211_key_seq * seq)1109 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
1110 			      int tid, struct ieee80211_key_seq *seq)
1111 {
1112 	struct ieee80211_key *key;
1113 	const u8 *pn;
1114 
1115 	key = container_of(keyconf, struct ieee80211_key, conf);
1116 
1117 	switch (key->conf.cipher) {
1118 	case WLAN_CIPHER_SUITE_TKIP:
1119 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1120 			return;
1121 		seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1122 		seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1123 		break;
1124 	case WLAN_CIPHER_SUITE_CCMP:
1125 	case WLAN_CIPHER_SUITE_CCMP_256:
1126 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1127 			return;
1128 		if (tid < 0)
1129 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1130 		else
1131 			pn = key->u.ccmp.rx_pn[tid];
1132 		memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1133 		break;
1134 	case WLAN_CIPHER_SUITE_AES_CMAC:
1135 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1136 		if (WARN_ON(tid != 0))
1137 			return;
1138 		pn = key->u.aes_cmac.rx_pn;
1139 		memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1140 		break;
1141 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1142 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1143 		if (WARN_ON(tid != 0))
1144 			return;
1145 		pn = key->u.aes_gmac.rx_pn;
1146 		memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1147 		break;
1148 	case WLAN_CIPHER_SUITE_GCMP:
1149 	case WLAN_CIPHER_SUITE_GCMP_256:
1150 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1151 			return;
1152 		if (tid < 0)
1153 			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1154 		else
1155 			pn = key->u.gcmp.rx_pn[tid];
1156 		memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1157 		break;
1158 	}
1159 }
1160 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1161 
ieee80211_set_key_rx_seq(struct ieee80211_key_conf * keyconf,int tid,struct ieee80211_key_seq * seq)1162 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1163 			      int tid, struct ieee80211_key_seq *seq)
1164 {
1165 	struct ieee80211_key *key;
1166 	u8 *pn;
1167 
1168 	key = container_of(keyconf, struct ieee80211_key, conf);
1169 
1170 	switch (key->conf.cipher) {
1171 	case WLAN_CIPHER_SUITE_TKIP:
1172 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1173 			return;
1174 		key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1175 		key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1176 		break;
1177 	case WLAN_CIPHER_SUITE_CCMP:
1178 	case WLAN_CIPHER_SUITE_CCMP_256:
1179 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1180 			return;
1181 		if (tid < 0)
1182 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1183 		else
1184 			pn = key->u.ccmp.rx_pn[tid];
1185 		memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1186 		break;
1187 	case WLAN_CIPHER_SUITE_AES_CMAC:
1188 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1189 		if (WARN_ON(tid != 0))
1190 			return;
1191 		pn = key->u.aes_cmac.rx_pn;
1192 		memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1193 		break;
1194 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1195 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1196 		if (WARN_ON(tid != 0))
1197 			return;
1198 		pn = key->u.aes_gmac.rx_pn;
1199 		memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1200 		break;
1201 	case WLAN_CIPHER_SUITE_GCMP:
1202 	case WLAN_CIPHER_SUITE_GCMP_256:
1203 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1204 			return;
1205 		if (tid < 0)
1206 			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1207 		else
1208 			pn = key->u.gcmp.rx_pn[tid];
1209 		memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1210 		break;
1211 	default:
1212 		WARN_ON(1);
1213 		break;
1214 	}
1215 }
1216 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1217 
ieee80211_remove_key(struct ieee80211_key_conf * keyconf)1218 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1219 {
1220 	struct ieee80211_key *key;
1221 
1222 	key = container_of(keyconf, struct ieee80211_key, conf);
1223 
1224 	assert_key_lock(key->local);
1225 
1226 	/*
1227 	 * if key was uploaded, we assume the driver will/has remove(d)
1228 	 * it, so adjust bookkeeping accordingly
1229 	 */
1230 	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1231 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1232 
1233 		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1234 					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
1235 					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1236 			increment_tailroom_need_count(key->sdata);
1237 	}
1238 
1239 	ieee80211_key_free(key, false);
1240 }
1241 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1242 
1243 struct ieee80211_key_conf *
ieee80211_gtk_rekey_add(struct ieee80211_vif * vif,struct ieee80211_key_conf * keyconf)1244 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1245 			struct ieee80211_key_conf *keyconf)
1246 {
1247 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1248 	struct ieee80211_local *local = sdata->local;
1249 	struct ieee80211_key *key;
1250 	int err;
1251 
1252 	if (WARN_ON(!local->wowlan))
1253 		return ERR_PTR(-EINVAL);
1254 
1255 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1256 		return ERR_PTR(-EINVAL);
1257 
1258 	key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1259 				  keyconf->keylen, keyconf->key,
1260 				  0, NULL, NULL);
1261 	if (IS_ERR(key))
1262 		return ERR_CAST(key);
1263 
1264 	if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1265 		key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1266 
1267 	err = ieee80211_key_link(key, sdata, NULL);
1268 	if (err)
1269 		return ERR_PTR(err);
1270 
1271 	return &key->conf;
1272 }
1273 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
1274