xref: /openbmc/linux/net/mac80211/key.c (revision 02e0e426)
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, 2022-2023  Intel Corporation
10  */
11 
12 #include <crypto/utils.h>
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 #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 	if (key->conf.link_id >= 0 && sdata->vif.active_links &&
181 	    !(sdata->vif.active_links & BIT(key->conf.link_id)))
182 		return 0;
183 
184 	ret = drv_set_key(key->local, SET_KEY, sdata,
185 			  sta ? &sta->sta : NULL, &key->conf);
186 
187 	if (!ret) {
188 		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
189 
190 		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
191 					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
192 					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
193 			decrease_tailroom_need_count(sdata, 1);
194 
195 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
196 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
197 
198 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
199 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
200 
201 		return 0;
202 	}
203 
204 	if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
205 		sdata_err(sdata,
206 			  "failed to set key (%d, %pM) to hardware (%d)\n",
207 			  key->conf.keyidx,
208 			  sta ? sta->sta.addr : bcast_addr, ret);
209 
210  out_unsupported:
211 	switch (key->conf.cipher) {
212 	case WLAN_CIPHER_SUITE_WEP40:
213 	case WLAN_CIPHER_SUITE_WEP104:
214 	case WLAN_CIPHER_SUITE_TKIP:
215 	case WLAN_CIPHER_SUITE_CCMP:
216 	case WLAN_CIPHER_SUITE_CCMP_256:
217 	case WLAN_CIPHER_SUITE_GCMP:
218 	case WLAN_CIPHER_SUITE_GCMP_256:
219 	case WLAN_CIPHER_SUITE_AES_CMAC:
220 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
221 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
222 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
223 		/* all of these we can do in software - if driver can */
224 		if (ret == 1)
225 			return 0;
226 		if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
227 			return -EINVAL;
228 		return 0;
229 	default:
230 		return -EINVAL;
231 	}
232 }
233 
ieee80211_key_disable_hw_accel(struct ieee80211_key * key)234 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
235 {
236 	struct ieee80211_sub_if_data *sdata;
237 	struct sta_info *sta;
238 	int ret;
239 
240 	might_sleep();
241 
242 	if (!key || !key->local->ops->set_key)
243 		return;
244 
245 	assert_key_lock(key->local);
246 
247 	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
248 		return;
249 
250 	sta = key->sta;
251 	sdata = key->sdata;
252 
253 	if (key->conf.link_id >= 0 && sdata->vif.active_links &&
254 	    !(sdata->vif.active_links & BIT(key->conf.link_id)))
255 		return;
256 
257 	if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
258 				 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
259 				 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
260 		increment_tailroom_need_count(sdata);
261 
262 	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
263 	ret = drv_set_key(key->local, DISABLE_KEY, sdata,
264 			  sta ? &sta->sta : NULL, &key->conf);
265 
266 	if (ret)
267 		sdata_err(sdata,
268 			  "failed to remove key (%d, %pM) from hardware (%d)\n",
269 			  key->conf.keyidx,
270 			  sta ? sta->sta.addr : bcast_addr, ret);
271 }
272 
_ieee80211_set_tx_key(struct ieee80211_key * key,bool force)273 static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force)
274 {
275 	struct sta_info *sta = key->sta;
276 	struct ieee80211_local *local = key->local;
277 
278 	assert_key_lock(local);
279 
280 	set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION);
281 
282 	sta->ptk_idx = key->conf.keyidx;
283 
284 	if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
285 		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
286 	ieee80211_check_fast_xmit(sta);
287 
288 	return 0;
289 }
290 
ieee80211_set_tx_key(struct ieee80211_key * key)291 int ieee80211_set_tx_key(struct ieee80211_key *key)
292 {
293 	return _ieee80211_set_tx_key(key, false);
294 }
295 
ieee80211_pairwise_rekey(struct ieee80211_key * old,struct ieee80211_key * new)296 static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
297 				     struct ieee80211_key *new)
298 {
299 	struct ieee80211_local *local = new->local;
300 	struct sta_info *sta = new->sta;
301 	int i;
302 
303 	assert_key_lock(local);
304 
305 	if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) {
306 		/* Extended Key ID key install, initial one or rekey */
307 
308 		if (sta->ptk_idx != INVALID_PTK_KEYIDX &&
309 		    !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) {
310 			/* Aggregation Sessions with Extended Key ID must not
311 			 * mix MPDUs with different keyIDs within one A-MPDU.
312 			 * Tear down running Tx aggregation sessions and block
313 			 * new Rx/Tx aggregation requests during rekey to
314 			 * ensure there are no A-MPDUs when the driver is not
315 			 * supporting A-MPDU key borders. (Blocking Tx only
316 			 * would be sufficient but WLAN_STA_BLOCK_BA gets the
317 			 * job done for the few ms we need it.)
318 			 */
319 			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
320 			mutex_lock(&sta->ampdu_mlme.mtx);
321 			for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
322 				___ieee80211_stop_tx_ba_session(sta, i,
323 								AGG_STOP_LOCAL_REQUEST);
324 			mutex_unlock(&sta->ampdu_mlme.mtx);
325 		}
326 	} else if (old) {
327 		/* Rekey without Extended Key ID.
328 		 * Aggregation sessions are OK when running on SW crypto.
329 		 * A broken remote STA may cause issues not observed with HW
330 		 * crypto, though.
331 		 */
332 		if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
333 			return;
334 
335 		/* Stop Tx till we are on the new key */
336 		old->flags |= KEY_FLAG_TAINTED;
337 		ieee80211_clear_fast_xmit(sta);
338 		if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
339 			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
340 			ieee80211_sta_tear_down_BA_sessions(sta,
341 							    AGG_STOP_LOCAL_REQUEST);
342 		}
343 		if (!wiphy_ext_feature_isset(local->hw.wiphy,
344 					     NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) {
345 			pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.",
346 					    sta->sta.addr);
347 			/* Flushing the driver queues *may* help prevent
348 			 * the clear text leaks and freezes.
349 			 */
350 			ieee80211_flush_queues(local, old->sdata, false);
351 		}
352 	}
353 }
354 
__ieee80211_set_default_key(struct ieee80211_link_data * link,int idx,bool uni,bool multi)355 static void __ieee80211_set_default_key(struct ieee80211_link_data *link,
356 					int idx, bool uni, bool multi)
357 {
358 	struct ieee80211_sub_if_data *sdata = link->sdata;
359 	struct ieee80211_key *key = NULL;
360 
361 	assert_key_lock(sdata->local);
362 
363 	if (idx >= 0 && idx < NUM_DEFAULT_KEYS) {
364 		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
365 		if (!key)
366 			key = key_mtx_dereference(sdata->local, link->gtk[idx]);
367 	}
368 
369 	if (uni) {
370 		rcu_assign_pointer(sdata->default_unicast_key, key);
371 		ieee80211_check_fast_xmit_iface(sdata);
372 		if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
373 			drv_set_default_unicast_key(sdata->local, sdata, idx);
374 	}
375 
376 	if (multi)
377 		rcu_assign_pointer(link->default_multicast_key, key);
378 
379 	ieee80211_debugfs_key_update_default(sdata);
380 }
381 
ieee80211_set_default_key(struct ieee80211_link_data * link,int idx,bool uni,bool multi)382 void ieee80211_set_default_key(struct ieee80211_link_data *link, int idx,
383 			       bool uni, bool multi)
384 {
385 	mutex_lock(&link->sdata->local->key_mtx);
386 	__ieee80211_set_default_key(link, idx, uni, multi);
387 	mutex_unlock(&link->sdata->local->key_mtx);
388 }
389 
390 static void
__ieee80211_set_default_mgmt_key(struct ieee80211_link_data * link,int idx)391 __ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link, int idx)
392 {
393 	struct ieee80211_sub_if_data *sdata = link->sdata;
394 	struct ieee80211_key *key = NULL;
395 
396 	assert_key_lock(sdata->local);
397 
398 	if (idx >= NUM_DEFAULT_KEYS &&
399 	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
400 		key = key_mtx_dereference(sdata->local, link->gtk[idx]);
401 
402 	rcu_assign_pointer(link->default_mgmt_key, key);
403 
404 	ieee80211_debugfs_key_update_default(sdata);
405 }
406 
ieee80211_set_default_mgmt_key(struct ieee80211_link_data * link,int idx)407 void ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link,
408 				    int idx)
409 {
410 	mutex_lock(&link->sdata->local->key_mtx);
411 	__ieee80211_set_default_mgmt_key(link, idx);
412 	mutex_unlock(&link->sdata->local->key_mtx);
413 }
414 
415 static void
__ieee80211_set_default_beacon_key(struct ieee80211_link_data * link,int idx)416 __ieee80211_set_default_beacon_key(struct ieee80211_link_data *link, int idx)
417 {
418 	struct ieee80211_sub_if_data *sdata = link->sdata;
419 	struct ieee80211_key *key = NULL;
420 
421 	assert_key_lock(sdata->local);
422 
423 	if (idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS &&
424 	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
425 	    NUM_DEFAULT_BEACON_KEYS)
426 		key = key_mtx_dereference(sdata->local, link->gtk[idx]);
427 
428 	rcu_assign_pointer(link->default_beacon_key, key);
429 
430 	ieee80211_debugfs_key_update_default(sdata);
431 }
432 
ieee80211_set_default_beacon_key(struct ieee80211_link_data * link,int idx)433 void ieee80211_set_default_beacon_key(struct ieee80211_link_data *link,
434 				      int idx)
435 {
436 	mutex_lock(&link->sdata->local->key_mtx);
437 	__ieee80211_set_default_beacon_key(link, idx);
438 	mutex_unlock(&link->sdata->local->key_mtx);
439 }
440 
ieee80211_key_replace(struct ieee80211_sub_if_data * sdata,struct ieee80211_link_data * link,struct sta_info * sta,bool pairwise,struct ieee80211_key * old,struct ieee80211_key * new)441 static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
442 				 struct ieee80211_link_data *link,
443 				 struct sta_info *sta,
444 				 bool pairwise,
445 				 struct ieee80211_key *old,
446 				 struct ieee80211_key *new)
447 {
448 	struct link_sta_info *link_sta = sta ? &sta->deflink : NULL;
449 	int link_id;
450 	int idx;
451 	int ret = 0;
452 	bool defunikey, defmultikey, defmgmtkey, defbeaconkey;
453 	bool is_wep;
454 
455 	/* caller must provide at least one old/new */
456 	if (WARN_ON(!new && !old))
457 		return 0;
458 
459 	if (new) {
460 		idx = new->conf.keyidx;
461 		is_wep = new->conf.cipher == WLAN_CIPHER_SUITE_WEP40 ||
462 			 new->conf.cipher == WLAN_CIPHER_SUITE_WEP104;
463 		link_id = new->conf.link_id;
464 	} else {
465 		idx = old->conf.keyidx;
466 		is_wep = old->conf.cipher == WLAN_CIPHER_SUITE_WEP40 ||
467 			 old->conf.cipher == WLAN_CIPHER_SUITE_WEP104;
468 		link_id = old->conf.link_id;
469 	}
470 
471 	if (WARN(old && old->conf.link_id != link_id,
472 		 "old link ID %d doesn't match new link ID %d\n",
473 		 old->conf.link_id, link_id))
474 		return -EINVAL;
475 
476 	if (link_id >= 0) {
477 		if (!link) {
478 			link = sdata_dereference(sdata->link[link_id], sdata);
479 			if (!link)
480 				return -ENOLINK;
481 		}
482 
483 		if (sta) {
484 			link_sta = rcu_dereference_protected(sta->link[link_id],
485 							     lockdep_is_held(&sta->local->sta_mtx));
486 			if (!link_sta)
487 				return -ENOLINK;
488 		}
489 	} else {
490 		link = &sdata->deflink;
491 	}
492 
493 	if ((is_wep || pairwise) && idx >= NUM_DEFAULT_KEYS)
494 		return -EINVAL;
495 
496 	WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
497 
498 	if (new && sta && pairwise) {
499 		/* Unicast rekey needs special handling. With Extended Key ID
500 		 * old is still NULL for the first rekey.
501 		 */
502 		ieee80211_pairwise_rekey(old, new);
503 	}
504 
505 	if (old) {
506 		if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
507 			ieee80211_key_disable_hw_accel(old);
508 
509 			if (new)
510 				ret = ieee80211_key_enable_hw_accel(new);
511 		}
512 	} else {
513 		if (!new->local->wowlan) {
514 			ret = ieee80211_key_enable_hw_accel(new);
515 		} else {
516 			assert_key_lock(new->local);
517 			new->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
518 		}
519 	}
520 
521 	if (ret)
522 		return ret;
523 
524 	if (new)
525 		list_add_tail_rcu(&new->list, &sdata->key_list);
526 
527 	if (sta) {
528 		if (pairwise) {
529 			rcu_assign_pointer(sta->ptk[idx], new);
530 			if (new &&
531 			    !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX))
532 				_ieee80211_set_tx_key(new, true);
533 		} else {
534 			rcu_assign_pointer(link_sta->gtk[idx], new);
535 		}
536 		/* Only needed for transition from no key -> key.
537 		 * Still triggers unnecessary when using Extended Key ID
538 		 * and installing the second key ID the first time.
539 		 */
540 		if (new && !old)
541 			ieee80211_check_fast_rx(sta);
542 	} else {
543 		defunikey = old &&
544 			old == key_mtx_dereference(sdata->local,
545 						sdata->default_unicast_key);
546 		defmultikey = old &&
547 			old == key_mtx_dereference(sdata->local,
548 						   link->default_multicast_key);
549 		defmgmtkey = old &&
550 			old == key_mtx_dereference(sdata->local,
551 						   link->default_mgmt_key);
552 		defbeaconkey = old &&
553 			old == key_mtx_dereference(sdata->local,
554 						   link->default_beacon_key);
555 
556 		if (defunikey && !new)
557 			__ieee80211_set_default_key(link, -1, true, false);
558 		if (defmultikey && !new)
559 			__ieee80211_set_default_key(link, -1, false, true);
560 		if (defmgmtkey && !new)
561 			__ieee80211_set_default_mgmt_key(link, -1);
562 		if (defbeaconkey && !new)
563 			__ieee80211_set_default_beacon_key(link, -1);
564 
565 		if (is_wep || pairwise)
566 			rcu_assign_pointer(sdata->keys[idx], new);
567 		else
568 			rcu_assign_pointer(link->gtk[idx], new);
569 
570 		if (defunikey && new)
571 			__ieee80211_set_default_key(link, new->conf.keyidx,
572 						    true, false);
573 		if (defmultikey && new)
574 			__ieee80211_set_default_key(link, new->conf.keyidx,
575 						    false, true);
576 		if (defmgmtkey && new)
577 			__ieee80211_set_default_mgmt_key(link,
578 							 new->conf.keyidx);
579 		if (defbeaconkey && new)
580 			__ieee80211_set_default_beacon_key(link,
581 							   new->conf.keyidx);
582 	}
583 
584 	if (old)
585 		list_del_rcu(&old->list);
586 
587 	return 0;
588 }
589 
590 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)591 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
592 		    const u8 *key_data,
593 		    size_t seq_len, const u8 *seq)
594 {
595 	struct ieee80211_key *key;
596 	int i, j, err;
597 
598 	if (WARN_ON(idx < 0 ||
599 		    idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
600 		    NUM_DEFAULT_BEACON_KEYS))
601 		return ERR_PTR(-EINVAL);
602 
603 	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
604 	if (!key)
605 		return ERR_PTR(-ENOMEM);
606 
607 	/*
608 	 * Default to software encryption; we'll later upload the
609 	 * key to the hardware if possible.
610 	 */
611 	key->conf.flags = 0;
612 	key->flags = 0;
613 
614 	key->conf.link_id = -1;
615 	key->conf.cipher = cipher;
616 	key->conf.keyidx = idx;
617 	key->conf.keylen = key_len;
618 	switch (cipher) {
619 	case WLAN_CIPHER_SUITE_WEP40:
620 	case WLAN_CIPHER_SUITE_WEP104:
621 		key->conf.iv_len = IEEE80211_WEP_IV_LEN;
622 		key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
623 		break;
624 	case WLAN_CIPHER_SUITE_TKIP:
625 		key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
626 		key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
627 		if (seq) {
628 			for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
629 				key->u.tkip.rx[i].iv32 =
630 					get_unaligned_le32(&seq[2]);
631 				key->u.tkip.rx[i].iv16 =
632 					get_unaligned_le16(seq);
633 			}
634 		}
635 		spin_lock_init(&key->u.tkip.txlock);
636 		break;
637 	case WLAN_CIPHER_SUITE_CCMP:
638 		key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
639 		key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
640 		if (seq) {
641 			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
642 				for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
643 					key->u.ccmp.rx_pn[i][j] =
644 						seq[IEEE80211_CCMP_PN_LEN - j - 1];
645 		}
646 		/*
647 		 * Initialize AES key state here as an optimization so that
648 		 * it does not need to be initialized for every packet.
649 		 */
650 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
651 			key_data, key_len, IEEE80211_CCMP_MIC_LEN);
652 		if (IS_ERR(key->u.ccmp.tfm)) {
653 			err = PTR_ERR(key->u.ccmp.tfm);
654 			kfree(key);
655 			return ERR_PTR(err);
656 		}
657 		break;
658 	case WLAN_CIPHER_SUITE_CCMP_256:
659 		key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
660 		key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
661 		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
662 			for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
663 				key->u.ccmp.rx_pn[i][j] =
664 					seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
665 		/* Initialize AES key state here as an optimization so that
666 		 * it does not need to be initialized for every packet.
667 		 */
668 		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
669 			key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
670 		if (IS_ERR(key->u.ccmp.tfm)) {
671 			err = PTR_ERR(key->u.ccmp.tfm);
672 			kfree(key);
673 			return ERR_PTR(err);
674 		}
675 		break;
676 	case WLAN_CIPHER_SUITE_AES_CMAC:
677 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
678 		key->conf.iv_len = 0;
679 		if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
680 			key->conf.icv_len = sizeof(struct ieee80211_mmie);
681 		else
682 			key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
683 		if (seq)
684 			for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
685 				key->u.aes_cmac.rx_pn[j] =
686 					seq[IEEE80211_CMAC_PN_LEN - j - 1];
687 		/*
688 		 * Initialize AES key state here as an optimization so that
689 		 * it does not need to be initialized for every packet.
690 		 */
691 		key->u.aes_cmac.tfm =
692 			ieee80211_aes_cmac_key_setup(key_data, key_len);
693 		if (IS_ERR(key->u.aes_cmac.tfm)) {
694 			err = PTR_ERR(key->u.aes_cmac.tfm);
695 			kfree(key);
696 			return ERR_PTR(err);
697 		}
698 		break;
699 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
700 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
701 		key->conf.iv_len = 0;
702 		key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
703 		if (seq)
704 			for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
705 				key->u.aes_gmac.rx_pn[j] =
706 					seq[IEEE80211_GMAC_PN_LEN - j - 1];
707 		/* Initialize AES key state here as an optimization so that
708 		 * it does not need to be initialized for every packet.
709 		 */
710 		key->u.aes_gmac.tfm =
711 			ieee80211_aes_gmac_key_setup(key_data, key_len);
712 		if (IS_ERR(key->u.aes_gmac.tfm)) {
713 			err = PTR_ERR(key->u.aes_gmac.tfm);
714 			kfree(key);
715 			return ERR_PTR(err);
716 		}
717 		break;
718 	case WLAN_CIPHER_SUITE_GCMP:
719 	case WLAN_CIPHER_SUITE_GCMP_256:
720 		key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
721 		key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
722 		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
723 			for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
724 				key->u.gcmp.rx_pn[i][j] =
725 					seq[IEEE80211_GCMP_PN_LEN - j - 1];
726 		/* Initialize AES key state here as an optimization so that
727 		 * it does not need to be initialized for every packet.
728 		 */
729 		key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
730 								      key_len);
731 		if (IS_ERR(key->u.gcmp.tfm)) {
732 			err = PTR_ERR(key->u.gcmp.tfm);
733 			kfree(key);
734 			return ERR_PTR(err);
735 		}
736 		break;
737 	}
738 	memcpy(key->conf.key, key_data, key_len);
739 	INIT_LIST_HEAD(&key->list);
740 
741 	return key;
742 }
743 
ieee80211_key_free_common(struct ieee80211_key * key)744 static void ieee80211_key_free_common(struct ieee80211_key *key)
745 {
746 	switch (key->conf.cipher) {
747 	case WLAN_CIPHER_SUITE_CCMP:
748 	case WLAN_CIPHER_SUITE_CCMP_256:
749 		ieee80211_aes_key_free(key->u.ccmp.tfm);
750 		break;
751 	case WLAN_CIPHER_SUITE_AES_CMAC:
752 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
753 		ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
754 		break;
755 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
756 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
757 		ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
758 		break;
759 	case WLAN_CIPHER_SUITE_GCMP:
760 	case WLAN_CIPHER_SUITE_GCMP_256:
761 		ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
762 		break;
763 	}
764 	kfree_sensitive(key);
765 }
766 
__ieee80211_key_destroy(struct ieee80211_key * key,bool delay_tailroom)767 static void __ieee80211_key_destroy(struct ieee80211_key *key,
768 				    bool delay_tailroom)
769 {
770 	if (key->local) {
771 		struct ieee80211_sub_if_data *sdata = key->sdata;
772 
773 		ieee80211_debugfs_key_remove(key);
774 
775 		if (delay_tailroom) {
776 			/* see ieee80211_delayed_tailroom_dec */
777 			sdata->crypto_tx_tailroom_pending_dec++;
778 			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
779 					      HZ/2);
780 		} else {
781 			decrease_tailroom_need_count(sdata, 1);
782 		}
783 	}
784 
785 	ieee80211_key_free_common(key);
786 }
787 
ieee80211_key_destroy(struct ieee80211_key * key,bool delay_tailroom)788 static void ieee80211_key_destroy(struct ieee80211_key *key,
789 				  bool delay_tailroom)
790 {
791 	if (!key)
792 		return;
793 
794 	/*
795 	 * Synchronize so the TX path and rcu key iterators
796 	 * can no longer be using this key before we free/remove it.
797 	 */
798 	synchronize_net();
799 
800 	__ieee80211_key_destroy(key, delay_tailroom);
801 }
802 
ieee80211_key_free_unused(struct ieee80211_key * key)803 void ieee80211_key_free_unused(struct ieee80211_key *key)
804 {
805 	if (!key)
806 		return;
807 
808 	WARN_ON(key->sdata || key->local);
809 	ieee80211_key_free_common(key);
810 }
811 
ieee80211_key_identical(struct ieee80211_sub_if_data * sdata,struct ieee80211_key * old,struct ieee80211_key * new)812 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
813 				    struct ieee80211_key *old,
814 				    struct ieee80211_key *new)
815 {
816 	u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
817 	u8 *tk_old, *tk_new;
818 
819 	if (!old || new->conf.keylen != old->conf.keylen)
820 		return false;
821 
822 	tk_old = old->conf.key;
823 	tk_new = new->conf.key;
824 
825 	/*
826 	 * In station mode, don't compare the TX MIC key, as it's never used
827 	 * and offloaded rekeying may not care to send it to the host. This
828 	 * is the case in iwlwifi, for example.
829 	 */
830 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
831 	    new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
832 	    new->conf.keylen == WLAN_KEY_LEN_TKIP &&
833 	    !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
834 		memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
835 		memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
836 		memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
837 		memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
838 		tk_old = tkip_old;
839 		tk_new = tkip_new;
840 	}
841 
842 	return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
843 }
844 
ieee80211_key_link(struct ieee80211_key * key,struct ieee80211_link_data * link,struct sta_info * sta)845 int ieee80211_key_link(struct ieee80211_key *key,
846 		       struct ieee80211_link_data *link,
847 		       struct sta_info *sta)
848 {
849 	struct ieee80211_sub_if_data *sdata = link->sdata;
850 	static atomic_t key_color = ATOMIC_INIT(0);
851 	struct ieee80211_key *old_key = NULL;
852 	int idx = key->conf.keyidx;
853 	bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
854 	/*
855 	 * We want to delay tailroom updates only for station - in that
856 	 * case it helps roaming speed, but in other cases it hurts and
857 	 * can cause warnings to appear.
858 	 */
859 	bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
860 	int ret;
861 
862 	mutex_lock(&sdata->local->key_mtx);
863 
864 	if (sta && pairwise) {
865 		struct ieee80211_key *alt_key;
866 
867 		old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
868 		alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]);
869 
870 		/* The rekey code assumes that the old and new key are using
871 		 * the same cipher. Enforce the assumption for pairwise keys.
872 		 */
873 		if ((alt_key && alt_key->conf.cipher != key->conf.cipher) ||
874 		    (old_key && old_key->conf.cipher != key->conf.cipher)) {
875 			ret = -EOPNOTSUPP;
876 			goto out;
877 		}
878 	} else if (sta) {
879 		struct link_sta_info *link_sta = &sta->deflink;
880 		int link_id = key->conf.link_id;
881 
882 		if (link_id >= 0) {
883 			link_sta = rcu_dereference_protected(sta->link[link_id],
884 							     lockdep_is_held(&sta->local->sta_mtx));
885 			if (!link_sta) {
886 				ret = -ENOLINK;
887 				goto out;
888 			}
889 		}
890 
891 		old_key = key_mtx_dereference(sdata->local, link_sta->gtk[idx]);
892 	} else {
893 		if (idx < NUM_DEFAULT_KEYS)
894 			old_key = key_mtx_dereference(sdata->local,
895 						      sdata->keys[idx]);
896 		if (!old_key)
897 			old_key = key_mtx_dereference(sdata->local,
898 						      link->gtk[idx]);
899 	}
900 
901 	/* Non-pairwise keys must also not switch the cipher on rekey */
902 	if (!pairwise) {
903 		if (old_key && old_key->conf.cipher != key->conf.cipher) {
904 			ret = -EOPNOTSUPP;
905 			goto out;
906 		}
907 	}
908 
909 	/*
910 	 * Silently accept key re-installation without really installing the
911 	 * new version of the key to avoid nonce reuse or replay issues.
912 	 */
913 	if (ieee80211_key_identical(sdata, old_key, key)) {
914 		ret = -EALREADY;
915 		goto out;
916 	}
917 
918 	key->local = sdata->local;
919 	key->sdata = sdata;
920 	key->sta = sta;
921 
922 	/*
923 	 * Assign a unique ID to every key so we can easily prevent mixed
924 	 * key and fragment cache attacks.
925 	 */
926 	key->color = atomic_inc_return(&key_color);
927 
928 	increment_tailroom_need_count(sdata);
929 
930 	ret = ieee80211_key_replace(sdata, link, sta, pairwise, old_key, key);
931 
932 	if (!ret) {
933 		ieee80211_debugfs_key_add(key);
934 		ieee80211_key_destroy(old_key, delay_tailroom);
935 	} else {
936 		ieee80211_key_free(key, delay_tailroom);
937 	}
938 
939 	key = NULL;
940 
941  out:
942 	ieee80211_key_free_unused(key);
943 	mutex_unlock(&sdata->local->key_mtx);
944 
945 	return ret;
946 }
947 
ieee80211_key_free(struct ieee80211_key * key,bool delay_tailroom)948 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
949 {
950 	if (!key)
951 		return;
952 
953 	/*
954 	 * Replace key with nothingness if it was ever used.
955 	 */
956 	if (key->sdata)
957 		ieee80211_key_replace(key->sdata, NULL, key->sta,
958 				      key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
959 				      key, NULL);
960 	ieee80211_key_destroy(key, delay_tailroom);
961 }
962 
ieee80211_reenable_keys(struct ieee80211_sub_if_data * sdata)963 void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata)
964 {
965 	struct ieee80211_key *key;
966 	struct ieee80211_sub_if_data *vlan;
967 
968 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
969 
970 	mutex_lock(&sdata->local->key_mtx);
971 
972 	sdata->crypto_tx_tailroom_needed_cnt = 0;
973 	sdata->crypto_tx_tailroom_pending_dec = 0;
974 
975 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
976 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
977 			vlan->crypto_tx_tailroom_needed_cnt = 0;
978 			vlan->crypto_tx_tailroom_pending_dec = 0;
979 		}
980 	}
981 
982 	if (ieee80211_sdata_running(sdata)) {
983 		list_for_each_entry(key, &sdata->key_list, list) {
984 			increment_tailroom_need_count(sdata);
985 			ieee80211_key_enable_hw_accel(key);
986 		}
987 	}
988 
989 	mutex_unlock(&sdata->local->key_mtx);
990 }
991 
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)992 void ieee80211_iter_keys(struct ieee80211_hw *hw,
993 			 struct ieee80211_vif *vif,
994 			 void (*iter)(struct ieee80211_hw *hw,
995 				      struct ieee80211_vif *vif,
996 				      struct ieee80211_sta *sta,
997 				      struct ieee80211_key_conf *key,
998 				      void *data),
999 			 void *iter_data)
1000 {
1001 	struct ieee80211_local *local = hw_to_local(hw);
1002 	struct ieee80211_key *key, *tmp;
1003 	struct ieee80211_sub_if_data *sdata;
1004 
1005 	lockdep_assert_wiphy(hw->wiphy);
1006 
1007 	mutex_lock(&local->key_mtx);
1008 	if (vif) {
1009 		sdata = vif_to_sdata(vif);
1010 		list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
1011 			iter(hw, &sdata->vif,
1012 			     key->sta ? &key->sta->sta : NULL,
1013 			     &key->conf, iter_data);
1014 	} else {
1015 		list_for_each_entry(sdata, &local->interfaces, list)
1016 			list_for_each_entry_safe(key, tmp,
1017 						 &sdata->key_list, list)
1018 				iter(hw, &sdata->vif,
1019 				     key->sta ? &key->sta->sta : NULL,
1020 				     &key->conf, iter_data);
1021 	}
1022 	mutex_unlock(&local->key_mtx);
1023 }
1024 EXPORT_SYMBOL(ieee80211_iter_keys);
1025 
1026 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)1027 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
1028 			 struct ieee80211_sub_if_data *sdata,
1029 			 void (*iter)(struct ieee80211_hw *hw,
1030 				      struct ieee80211_vif *vif,
1031 				      struct ieee80211_sta *sta,
1032 				      struct ieee80211_key_conf *key,
1033 				      void *data),
1034 			 void *iter_data)
1035 {
1036 	struct ieee80211_key *key;
1037 
1038 	list_for_each_entry_rcu(key, &sdata->key_list, list) {
1039 		/* skip keys of station in removal process */
1040 		if (key->sta && key->sta->removed)
1041 			continue;
1042 		if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
1043 			continue;
1044 
1045 		iter(hw, &sdata->vif,
1046 		     key->sta ? &key->sta->sta : NULL,
1047 		     &key->conf, iter_data);
1048 	}
1049 }
1050 
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)1051 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
1052 			     struct ieee80211_vif *vif,
1053 			     void (*iter)(struct ieee80211_hw *hw,
1054 					  struct ieee80211_vif *vif,
1055 					  struct ieee80211_sta *sta,
1056 					  struct ieee80211_key_conf *key,
1057 					  void *data),
1058 			     void *iter_data)
1059 {
1060 	struct ieee80211_local *local = hw_to_local(hw);
1061 	struct ieee80211_sub_if_data *sdata;
1062 
1063 	if (vif) {
1064 		sdata = vif_to_sdata(vif);
1065 		_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
1066 	} else {
1067 		list_for_each_entry_rcu(sdata, &local->interfaces, list)
1068 			_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
1069 	}
1070 }
1071 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
1072 
ieee80211_free_keys_iface(struct ieee80211_sub_if_data * sdata,struct list_head * keys)1073 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
1074 				      struct list_head *keys)
1075 {
1076 	struct ieee80211_key *key, *tmp;
1077 
1078 	decrease_tailroom_need_count(sdata,
1079 				     sdata->crypto_tx_tailroom_pending_dec);
1080 	sdata->crypto_tx_tailroom_pending_dec = 0;
1081 
1082 	ieee80211_debugfs_key_remove_mgmt_default(sdata);
1083 	ieee80211_debugfs_key_remove_beacon_default(sdata);
1084 
1085 	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
1086 		ieee80211_key_replace(key->sdata, NULL, key->sta,
1087 				      key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1088 				      key, NULL);
1089 		list_add_tail(&key->list, keys);
1090 	}
1091 
1092 	ieee80211_debugfs_key_update_default(sdata);
1093 }
1094 
ieee80211_remove_link_keys(struct ieee80211_link_data * link,struct list_head * keys)1095 void ieee80211_remove_link_keys(struct ieee80211_link_data *link,
1096 				struct list_head *keys)
1097 {
1098 	struct ieee80211_sub_if_data *sdata = link->sdata;
1099 	struct ieee80211_local *local = sdata->local;
1100 	struct ieee80211_key *key, *tmp;
1101 
1102 	mutex_lock(&local->key_mtx);
1103 	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
1104 		if (key->conf.link_id != link->link_id)
1105 			continue;
1106 		ieee80211_key_replace(key->sdata, link, key->sta,
1107 				      key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1108 				      key, NULL);
1109 		list_add_tail(&key->list, keys);
1110 	}
1111 	mutex_unlock(&local->key_mtx);
1112 }
1113 
ieee80211_free_key_list(struct ieee80211_local * local,struct list_head * keys)1114 void ieee80211_free_key_list(struct ieee80211_local *local,
1115 			     struct list_head *keys)
1116 {
1117 	struct ieee80211_key *key, *tmp;
1118 
1119 	mutex_lock(&local->key_mtx);
1120 	list_for_each_entry_safe(key, tmp, keys, list)
1121 		__ieee80211_key_destroy(key, false);
1122 	mutex_unlock(&local->key_mtx);
1123 }
1124 
ieee80211_free_keys(struct ieee80211_sub_if_data * sdata,bool force_synchronize)1125 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
1126 			 bool force_synchronize)
1127 {
1128 	struct ieee80211_local *local = sdata->local;
1129 	struct ieee80211_sub_if_data *vlan;
1130 	struct ieee80211_sub_if_data *master;
1131 	struct ieee80211_key *key, *tmp;
1132 	LIST_HEAD(keys);
1133 
1134 	cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
1135 
1136 	mutex_lock(&local->key_mtx);
1137 
1138 	ieee80211_free_keys_iface(sdata, &keys);
1139 
1140 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
1141 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1142 			ieee80211_free_keys_iface(vlan, &keys);
1143 	}
1144 
1145 	if (!list_empty(&keys) || force_synchronize)
1146 		synchronize_net();
1147 	list_for_each_entry_safe(key, tmp, &keys, list)
1148 		__ieee80211_key_destroy(key, false);
1149 
1150 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1151 		if (sdata->bss) {
1152 			master = container_of(sdata->bss,
1153 					      struct ieee80211_sub_if_data,
1154 					      u.ap);
1155 
1156 			WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
1157 				     master->crypto_tx_tailroom_needed_cnt);
1158 		}
1159 	} else {
1160 		WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
1161 			     sdata->crypto_tx_tailroom_pending_dec);
1162 	}
1163 
1164 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
1165 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1166 			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
1167 				     vlan->crypto_tx_tailroom_pending_dec);
1168 	}
1169 
1170 	mutex_unlock(&local->key_mtx);
1171 }
1172 
ieee80211_free_sta_keys(struct ieee80211_local * local,struct sta_info * sta)1173 void ieee80211_free_sta_keys(struct ieee80211_local *local,
1174 			     struct sta_info *sta)
1175 {
1176 	struct ieee80211_key *key;
1177 	int i;
1178 
1179 	mutex_lock(&local->key_mtx);
1180 	for (i = 0; i < ARRAY_SIZE(sta->deflink.gtk); i++) {
1181 		key = key_mtx_dereference(local, sta->deflink.gtk[i]);
1182 		if (!key)
1183 			continue;
1184 		ieee80211_key_replace(key->sdata, NULL, key->sta,
1185 				      key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1186 				      key, NULL);
1187 		__ieee80211_key_destroy(key, key->sdata->vif.type ==
1188 					NL80211_IFTYPE_STATION);
1189 	}
1190 
1191 	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1192 		key = key_mtx_dereference(local, sta->ptk[i]);
1193 		if (!key)
1194 			continue;
1195 		ieee80211_key_replace(key->sdata, NULL, key->sta,
1196 				      key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1197 				      key, NULL);
1198 		__ieee80211_key_destroy(key, key->sdata->vif.type ==
1199 					NL80211_IFTYPE_STATION);
1200 	}
1201 
1202 	mutex_unlock(&local->key_mtx);
1203 }
1204 
ieee80211_delayed_tailroom_dec(struct work_struct * wk)1205 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
1206 {
1207 	struct ieee80211_sub_if_data *sdata;
1208 
1209 	sdata = container_of(wk, struct ieee80211_sub_if_data,
1210 			     dec_tailroom_needed_wk.work);
1211 
1212 	/*
1213 	 * The reason for the delayed tailroom needed decrementing is to
1214 	 * make roaming faster: during roaming, all keys are first deleted
1215 	 * and then new keys are installed. The first new key causes the
1216 	 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
1217 	 * the cost of synchronize_net() (which can be slow). Avoid this
1218 	 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
1219 	 * key removal for a while, so if we roam the value is larger than
1220 	 * zero and no 0->1 transition happens.
1221 	 *
1222 	 * The cost is that if the AP switching was from an AP with keys
1223 	 * to one without, we still allocate tailroom while it would no
1224 	 * longer be needed. However, in the typical (fast) roaming case
1225 	 * within an ESS this usually won't happen.
1226 	 */
1227 
1228 	mutex_lock(&sdata->local->key_mtx);
1229 	decrease_tailroom_need_count(sdata,
1230 				     sdata->crypto_tx_tailroom_pending_dec);
1231 	sdata->crypto_tx_tailroom_pending_dec = 0;
1232 	mutex_unlock(&sdata->local->key_mtx);
1233 }
1234 
ieee80211_gtk_rekey_notify(struct ieee80211_vif * vif,const u8 * bssid,const u8 * replay_ctr,gfp_t gfp)1235 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
1236 				const u8 *replay_ctr, gfp_t gfp)
1237 {
1238 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1239 
1240 	trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
1241 
1242 	cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
1243 }
1244 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
1245 
ieee80211_get_key_rx_seq(struct ieee80211_key_conf * keyconf,int tid,struct ieee80211_key_seq * seq)1246 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
1247 			      int tid, struct ieee80211_key_seq *seq)
1248 {
1249 	struct ieee80211_key *key;
1250 	const u8 *pn;
1251 
1252 	key = container_of(keyconf, struct ieee80211_key, conf);
1253 
1254 	switch (key->conf.cipher) {
1255 	case WLAN_CIPHER_SUITE_TKIP:
1256 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1257 			return;
1258 		seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1259 		seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1260 		break;
1261 	case WLAN_CIPHER_SUITE_CCMP:
1262 	case WLAN_CIPHER_SUITE_CCMP_256:
1263 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1264 			return;
1265 		if (tid < 0)
1266 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1267 		else
1268 			pn = key->u.ccmp.rx_pn[tid];
1269 		memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1270 		break;
1271 	case WLAN_CIPHER_SUITE_AES_CMAC:
1272 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1273 		if (WARN_ON(tid != 0))
1274 			return;
1275 		pn = key->u.aes_cmac.rx_pn;
1276 		memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1277 		break;
1278 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1279 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1280 		if (WARN_ON(tid != 0))
1281 			return;
1282 		pn = key->u.aes_gmac.rx_pn;
1283 		memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1284 		break;
1285 	case WLAN_CIPHER_SUITE_GCMP:
1286 	case WLAN_CIPHER_SUITE_GCMP_256:
1287 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1288 			return;
1289 		if (tid < 0)
1290 			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1291 		else
1292 			pn = key->u.gcmp.rx_pn[tid];
1293 		memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1294 		break;
1295 	}
1296 }
1297 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1298 
ieee80211_set_key_rx_seq(struct ieee80211_key_conf * keyconf,int tid,struct ieee80211_key_seq * seq)1299 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1300 			      int tid, struct ieee80211_key_seq *seq)
1301 {
1302 	struct ieee80211_key *key;
1303 	u8 *pn;
1304 
1305 	key = container_of(keyconf, struct ieee80211_key, conf);
1306 
1307 	switch (key->conf.cipher) {
1308 	case WLAN_CIPHER_SUITE_TKIP:
1309 		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1310 			return;
1311 		key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1312 		key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1313 		break;
1314 	case WLAN_CIPHER_SUITE_CCMP:
1315 	case WLAN_CIPHER_SUITE_CCMP_256:
1316 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1317 			return;
1318 		if (tid < 0)
1319 			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1320 		else
1321 			pn = key->u.ccmp.rx_pn[tid];
1322 		memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1323 		break;
1324 	case WLAN_CIPHER_SUITE_AES_CMAC:
1325 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1326 		if (WARN_ON(tid != 0))
1327 			return;
1328 		pn = key->u.aes_cmac.rx_pn;
1329 		memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1330 		break;
1331 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1332 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1333 		if (WARN_ON(tid != 0))
1334 			return;
1335 		pn = key->u.aes_gmac.rx_pn;
1336 		memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1337 		break;
1338 	case WLAN_CIPHER_SUITE_GCMP:
1339 	case WLAN_CIPHER_SUITE_GCMP_256:
1340 		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1341 			return;
1342 		if (tid < 0)
1343 			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1344 		else
1345 			pn = key->u.gcmp.rx_pn[tid];
1346 		memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1347 		break;
1348 	default:
1349 		WARN_ON(1);
1350 		break;
1351 	}
1352 }
1353 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1354 
ieee80211_remove_key(struct ieee80211_key_conf * keyconf)1355 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1356 {
1357 	struct ieee80211_key *key;
1358 
1359 	key = container_of(keyconf, struct ieee80211_key, conf);
1360 
1361 	assert_key_lock(key->local);
1362 
1363 	/*
1364 	 * if key was uploaded, we assume the driver will/has remove(d)
1365 	 * it, so adjust bookkeeping accordingly
1366 	 */
1367 	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1368 		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1369 
1370 		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1371 					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
1372 					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1373 			increment_tailroom_need_count(key->sdata);
1374 	}
1375 
1376 	ieee80211_key_free(key, false);
1377 }
1378 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1379 
1380 struct ieee80211_key_conf *
ieee80211_gtk_rekey_add(struct ieee80211_vif * vif,struct ieee80211_key_conf * keyconf)1381 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1382 			struct ieee80211_key_conf *keyconf)
1383 {
1384 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1385 	struct ieee80211_local *local = sdata->local;
1386 	struct ieee80211_key *key;
1387 	int err;
1388 
1389 	if (WARN_ON(!local->wowlan))
1390 		return ERR_PTR(-EINVAL);
1391 
1392 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1393 		return ERR_PTR(-EINVAL);
1394 
1395 	key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1396 				  keyconf->keylen, keyconf->key,
1397 				  0, NULL);
1398 	if (IS_ERR(key))
1399 		return ERR_CAST(key);
1400 
1401 	if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1402 		key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1403 
1404 	/* FIXME: this function needs to get a link ID */
1405 	err = ieee80211_key_link(key, &sdata->deflink, NULL);
1406 	if (err)
1407 		return ERR_PTR(err);
1408 
1409 	return &key->conf;
1410 }
1411 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
1412 
ieee80211_key_mic_failure(struct ieee80211_key_conf * keyconf)1413 void ieee80211_key_mic_failure(struct ieee80211_key_conf *keyconf)
1414 {
1415 	struct ieee80211_key *key;
1416 
1417 	key = container_of(keyconf, struct ieee80211_key, conf);
1418 
1419 	switch (key->conf.cipher) {
1420 	case WLAN_CIPHER_SUITE_AES_CMAC:
1421 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1422 		key->u.aes_cmac.icverrors++;
1423 		break;
1424 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1425 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1426 		key->u.aes_gmac.icverrors++;
1427 		break;
1428 	default:
1429 		/* ignore the others for now, we don't keep counters now */
1430 		break;
1431 	}
1432 }
1433 EXPORT_SYMBOL_GPL(ieee80211_key_mic_failure);
1434 
ieee80211_key_replay(struct ieee80211_key_conf * keyconf)1435 void ieee80211_key_replay(struct ieee80211_key_conf *keyconf)
1436 {
1437 	struct ieee80211_key *key;
1438 
1439 	key = container_of(keyconf, struct ieee80211_key, conf);
1440 
1441 	switch (key->conf.cipher) {
1442 	case WLAN_CIPHER_SUITE_CCMP:
1443 	case WLAN_CIPHER_SUITE_CCMP_256:
1444 		key->u.ccmp.replays++;
1445 		break;
1446 	case WLAN_CIPHER_SUITE_AES_CMAC:
1447 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1448 		key->u.aes_cmac.replays++;
1449 		break;
1450 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1451 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1452 		key->u.aes_gmac.replays++;
1453 		break;
1454 	case WLAN_CIPHER_SUITE_GCMP:
1455 	case WLAN_CIPHER_SUITE_GCMP_256:
1456 		key->u.gcmp.replays++;
1457 		break;
1458 	}
1459 }
1460 EXPORT_SYMBOL_GPL(ieee80211_key_replay);
1461 
ieee80211_key_switch_links(struct ieee80211_sub_if_data * sdata,unsigned long del_links_mask,unsigned long add_links_mask)1462 int ieee80211_key_switch_links(struct ieee80211_sub_if_data *sdata,
1463 			       unsigned long del_links_mask,
1464 			       unsigned long add_links_mask)
1465 {
1466 	struct ieee80211_key *key;
1467 	int ret;
1468 
1469 	list_for_each_entry(key, &sdata->key_list, list) {
1470 		if (key->conf.link_id < 0 ||
1471 		    !(del_links_mask & BIT(key->conf.link_id)))
1472 			continue;
1473 
1474 		/* shouldn't happen for per-link keys */
1475 		WARN_ON(key->sta);
1476 
1477 		ieee80211_key_disable_hw_accel(key);
1478 	}
1479 
1480 	list_for_each_entry(key, &sdata->key_list, list) {
1481 		if (key->conf.link_id < 0 ||
1482 		    !(add_links_mask & BIT(key->conf.link_id)))
1483 			continue;
1484 
1485 		/* shouldn't happen for per-link keys */
1486 		WARN_ON(key->sta);
1487 
1488 		ret = ieee80211_key_enable_hw_accel(key);
1489 		if (ret)
1490 			return ret;
1491 	}
1492 
1493 	return 0;
1494 }
1495