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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / net / mac80211 / key.c
blobaee05ec3f7ea903bd4a4254c70529e7740092726
1 /*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net>
6 * Copyright 2013-2014 Intel Mobile Communications GmbH
7 * Copyright 2015-2017 Intel Deutschland GmbH
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14 #include <linux/if_ether.h>
15 #include <linux/etherdevice.h>
16 #include <linux/list.h>
17 #include <linux/rcupdate.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/slab.h>
20 #include <linux/export.h>
21 #include <net/mac80211.h>
22 #include <crypto/algapi.h>
23 #include <asm/unaligned.h>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "debugfs_key.h"
27 #include "aes_ccm.h"
28 #include "aes_cmac.h"
29 #include "aes_gmac.h"
30 #include "aes_gcm.h"
31
32
33 /**
34 * DOC: Key handling basics
35 *
36 * Key handling in mac80211 is done based on per-interface (sub_if_data)
37 * keys and per-station keys. Since each station belongs to an interface,
38 * each station key also belongs to that interface.
39 *
40 * Hardware acceleration is done on a best-effort basis for algorithms
41 * that are implemented in software, for each key the hardware is asked
42 * to enable that key for offloading but if it cannot do that the key is
43 * simply kept for software encryption (unless it is for an algorithm
44 * that isn't implemented in software).
45 * There is currently no way of knowing whether a key is handled in SW
46 * or HW except by looking into debugfs.
47 *
48 * All key management is internally protected by a mutex. Within all
49 * other parts of mac80211, key references are, just as STA structure
50 * references, protected by RCU. Note, however, that some things are
51 * unprotected, namely the key->sta dereferences within the hardware
52 * acceleration functions. This means that sta_info_destroy() must
53 * remove the key which waits for an RCU grace period.
54 */
55
56 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
57
58 static void assert_key_lock(struct ieee80211_local *local)
59 {
60 lockdep_assert_held(&local->key_mtx);
61 }
62
63 static void
64 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
65 {
66 struct ieee80211_sub_if_data *vlan;
67
68 if (sdata->vif.type != NL80211_IFTYPE_AP)
69 return;
70
71 /* crypto_tx_tailroom_needed_cnt is protected by this */
72 assert_key_lock(sdata->local);
73
74 rcu_read_lock();
75
76 list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
77 vlan->crypto_tx_tailroom_needed_cnt += delta;
78
79 rcu_read_unlock();
80 }
81
82 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
83 {
84 /*
85 * When this count is zero, SKB resizing for allocating tailroom
86 * for IV or MMIC is skipped. But, this check has created two race
87 * cases in xmit path while transiting from zero count to one:
88 *
89 * 1. SKB resize was skipped because no key was added but just before
90 * the xmit key is added and SW encryption kicks off.
91 *
92 * 2. SKB resize was skipped because all the keys were hw planted but
93 * just before xmit one of the key is deleted and SW encryption kicks
94 * off.
95 *
96 * In both the above case SW encryption will find not enough space for
97 * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
98 *
99 * Solution has been explained at
100 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
101 */
102
103 assert_key_lock(sdata->local);
104
105 update_vlan_tailroom_need_count(sdata, 1);
106
107 if (!sdata->crypto_tx_tailroom_needed_cnt++) {
108 /*
109 * Flush all XMIT packets currently using HW encryption or no
110 * encryption at all if the count transition is from 0 -> 1.
111 */
112 synchronize_net();
113 }
114 }
115
116 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
117 int delta)
118 {
119 assert_key_lock(sdata->local);
120
121 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
122
123 update_vlan_tailroom_need_count(sdata, -delta);
124 sdata->crypto_tx_tailroom_needed_cnt -= delta;
125 }
126
127 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
128 {
129 struct ieee80211_sub_if_data *sdata;
130 struct sta_info *sta;
131 int ret = -EOPNOTSUPP;
132
133 might_sleep();
134
135 if (key->flags & KEY_FLAG_TAINTED) {
136 /* If we get here, it's during resume and the key is
137 * tainted so shouldn't be used/programmed any more.
138 * However, its flags may still indicate that it was
139 * programmed into the device (since we're in resume)
140 * so clear that flag now to avoid trying to remove
141 * it again later.
142 */
143 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
144 return -EINVAL;
145 }
146
147 if (!key->local->ops->set_key)
148 goto out_unsupported;
149
150 assert_key_lock(key->local);
151
152 sta = key->sta;
153
154 /*
155 * If this is a per-STA GTK, check if it
156 * is supported; if not, return.
157 */
158 if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
159 !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
160 goto out_unsupported;
161
162 if (sta && !sta->uploaded)
163 goto out_unsupported;
164
165 sdata = key->sdata;
166 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
167 /*
168 * The driver doesn't know anything about VLAN interfaces.
169 * Hence, don't send GTKs for VLAN interfaces to the driver.
170 */
171 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
172 goto out_unsupported;
173 }
174
175 ret = drv_set_key(key->local, SET_KEY, sdata,
176 sta ? &sta->sta : NULL, &key->conf);
177
178 if (!ret) {
179 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
180
181 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
182 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
183 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
184 decrease_tailroom_need_count(sdata, 1);
185
186 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
187 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
188
189 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
190 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
191
192 return 0;
193 }
194
195 if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
196 sdata_err(sdata,
197 "failed to set key (%d, %pM) to hardware (%d)\n",
198 key->conf.keyidx,
199 sta ? sta->sta.addr : bcast_addr, ret);
200
201 out_unsupported:
202 switch (key->conf.cipher) {
203 case WLAN_CIPHER_SUITE_WEP40:
204 case WLAN_CIPHER_SUITE_WEP104:
205 case WLAN_CIPHER_SUITE_TKIP:
206 case WLAN_CIPHER_SUITE_CCMP:
207 case WLAN_CIPHER_SUITE_CCMP_256:
208 case WLAN_CIPHER_SUITE_AES_CMAC:
209 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
210 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
211 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
212 case WLAN_CIPHER_SUITE_GCMP:
213 case WLAN_CIPHER_SUITE_GCMP_256:
214 /* all of these we can do in software - if driver can */
215 if (ret == 1)
216 return 0;
217 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
218 return -EINVAL;
219 return 0;
220 default:
221 return -EINVAL;
222 }
223 }
224
225 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
226 {
227 struct ieee80211_sub_if_data *sdata;
228 struct sta_info *sta;
229 int ret;
230
231 might_sleep();
232
233 if (!key || !key->local->ops->set_key)
234 return;
235
236 assert_key_lock(key->local);
237
238 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
239 return;
240
241 sta = key->sta;
242 sdata = key->sdata;
243
244 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
245 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
246 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
247 increment_tailroom_need_count(sdata);
248
249 ret = drv_set_key(key->local, DISABLE_KEY, sdata,
250 sta ? &sta->sta : NULL, &key->conf);
251
252 if (ret)
253 sdata_err(sdata,
254 "failed to remove key (%d, %pM) from hardware (%d)\n",
255 key->conf.keyidx,
256 sta ? sta->sta.addr : bcast_addr, ret);
257
258 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
259 }
260
261 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
262 int idx, bool uni, bool multi)
263 {
264 struct ieee80211_key *key = NULL;
265
266 assert_key_lock(sdata->local);
267
268 if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
269 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
270
271 if (uni) {
272 rcu_assign_pointer(sdata->default_unicast_key, key);
273 ieee80211_check_fast_xmit_iface(sdata);
274 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
275 drv_set_default_unicast_key(sdata->local, sdata, idx);
276 }
277
278 if (multi)
279 rcu_assign_pointer(sdata->default_multicast_key, key);
280
281 ieee80211_debugfs_key_update_default(sdata);
282 }
283
284 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
285 bool uni, bool multi)
286 {
287 mutex_lock(&sdata->local->key_mtx);
288 __ieee80211_set_default_key(sdata, idx, uni, multi);
289 mutex_unlock(&sdata->local->key_mtx);
290 }
291
292 static void
293 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
294 {
295 struct ieee80211_key *key = NULL;
296
297 assert_key_lock(sdata->local);
298
299 if (idx >= NUM_DEFAULT_KEYS &&
300 idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
301 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
302
303 rcu_assign_pointer(sdata->default_mgmt_key, key);
304
305 ieee80211_debugfs_key_update_default(sdata);
306 }
307
308 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
309 int idx)
310 {
311 mutex_lock(&sdata->local->key_mtx);
312 __ieee80211_set_default_mgmt_key(sdata, idx);
313 mutex_unlock(&sdata->local->key_mtx);
314 }
315
316
317 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
318 struct sta_info *sta,
319 bool pairwise,
320 struct ieee80211_key *old,
321 struct ieee80211_key *new)
322 {
323 int idx;
324 bool defunikey, defmultikey, defmgmtkey;
325
326 /* caller must provide at least one old/new */
327 if (WARN_ON(!new && !old))
328 return;
329
330 if (new)
331 list_add_tail_rcu(&new->list, &sdata->key_list);
332
333 WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
334
335 if (old)
336 idx = old->conf.keyidx;
337 else
338 idx = new->conf.keyidx;
339
340 if (sta) {
341 if (pairwise) {
342 rcu_assign_pointer(sta->ptk[idx], new);
343 sta->ptk_idx = idx;
344 ieee80211_check_fast_xmit(sta);
345 } else {
346 rcu_assign_pointer(sta->gtk[idx], new);
347 }
348 ieee80211_check_fast_rx(sta);
349 } else {
350 defunikey = old &&
351 old == key_mtx_dereference(sdata->local,
352 sdata->default_unicast_key);
353 defmultikey = old &&
354 old == key_mtx_dereference(sdata->local,
355 sdata->default_multicast_key);
356 defmgmtkey = old &&
357 old == key_mtx_dereference(sdata->local,
358 sdata->default_mgmt_key);
359
360 if (defunikey && !new)
361 __ieee80211_set_default_key(sdata, -1, true, false);
362 if (defmultikey && !new)
363 __ieee80211_set_default_key(sdata, -1, false, true);
364 if (defmgmtkey && !new)
365 __ieee80211_set_default_mgmt_key(sdata, -1);
366
367 rcu_assign_pointer(sdata->keys[idx], new);
368 if (defunikey && new)
369 __ieee80211_set_default_key(sdata, new->conf.keyidx,
370 true, false);
371 if (defmultikey && new)
372 __ieee80211_set_default_key(sdata, new->conf.keyidx,
373 false, true);
374 if (defmgmtkey && new)
375 __ieee80211_set_default_mgmt_key(sdata,
376 new->conf.keyidx);
377 }
378
379 if (old)
380 list_del_rcu(&old->list);
381 }
382
383 struct ieee80211_key *
384 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
385 const u8 *key_data,
386 size_t seq_len, const u8 *seq,
387 const struct ieee80211_cipher_scheme *cs)
388 {
389 struct ieee80211_key *key;
390 int i, j, err;
391
392 if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
393 return ERR_PTR(-EINVAL);
394
395 key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
396 if (!key)
397 return ERR_PTR(-ENOMEM);
398
399 /*
400 * Default to software encryption; we'll later upload the
401 * key to the hardware if possible.
402 */
403 key->conf.flags = 0;
404 key->flags = 0;
405
406 key->conf.cipher = cipher;
407 key->conf.keyidx = idx;
408 key->conf.keylen = key_len;
409 switch (cipher) {
410 case WLAN_CIPHER_SUITE_WEP40:
411 case WLAN_CIPHER_SUITE_WEP104:
412 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
413 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
414 break;
415 case WLAN_CIPHER_SUITE_TKIP:
416 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
417 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
418 if (seq) {
419 for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
420 key->u.tkip.rx[i].iv32 =
421 get_unaligned_le32(&seq[2]);
422 key->u.tkip.rx[i].iv16 =
423 get_unaligned_le16(seq);
424 }
425 }
426 spin_lock_init(&key->u.tkip.txlock);
427 break;
428 case WLAN_CIPHER_SUITE_CCMP:
429 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
430 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
431 if (seq) {
432 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
433 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
434 key->u.ccmp.rx_pn[i][j] =
435 seq[IEEE80211_CCMP_PN_LEN - j - 1];
436 }
437 /*
438 * Initialize AES key state here as an optimization so that
439 * it does not need to be initialized for every packet.
440 */
441 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
442 key_data, key_len, IEEE80211_CCMP_MIC_LEN);
443 if (IS_ERR(key->u.ccmp.tfm)) {
444 err = PTR_ERR(key->u.ccmp.tfm);
445 kfree(key);
446 return ERR_PTR(err);
447 }
448 break;
449 case WLAN_CIPHER_SUITE_CCMP_256:
450 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
451 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
452 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
453 for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
454 key->u.ccmp.rx_pn[i][j] =
455 seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
456 /* Initialize AES key state here as an optimization so that
457 * it does not need to be initialized for every packet.
458 */
459 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
460 key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
461 if (IS_ERR(key->u.ccmp.tfm)) {
462 err = PTR_ERR(key->u.ccmp.tfm);
463 kfree(key);
464 return ERR_PTR(err);
465 }
466 break;
467 case WLAN_CIPHER_SUITE_AES_CMAC:
468 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
469 key->conf.iv_len = 0;
470 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
471 key->conf.icv_len = sizeof(struct ieee80211_mmie);
472 else
473 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
474 if (seq)
475 for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
476 key->u.aes_cmac.rx_pn[j] =
477 seq[IEEE80211_CMAC_PN_LEN - j - 1];
478 /*
479 * Initialize AES key state here as an optimization so that
480 * it does not need to be initialized for every packet.
481 */
482 key->u.aes_cmac.tfm =
483 ieee80211_aes_cmac_key_setup(key_data, key_len);
484 if (IS_ERR(key->u.aes_cmac.tfm)) {
485 err = PTR_ERR(key->u.aes_cmac.tfm);
486 kfree(key);
487 return ERR_PTR(err);
488 }
489 break;
490 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
491 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
492 key->conf.iv_len = 0;
493 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
494 if (seq)
495 for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
496 key->u.aes_gmac.rx_pn[j] =
497 seq[IEEE80211_GMAC_PN_LEN - j - 1];
498 /* Initialize AES key state here as an optimization so that
499 * it does not need to be initialized for every packet.
500 */
501 key->u.aes_gmac.tfm =
502 ieee80211_aes_gmac_key_setup(key_data, key_len);
503 if (IS_ERR(key->u.aes_gmac.tfm)) {
504 err = PTR_ERR(key->u.aes_gmac.tfm);
505 kfree(key);
506 return ERR_PTR(err);
507 }
508 break;
509 case WLAN_CIPHER_SUITE_GCMP:
510 case WLAN_CIPHER_SUITE_GCMP_256:
511 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
512 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
513 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
514 for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
515 key->u.gcmp.rx_pn[i][j] =
516 seq[IEEE80211_GCMP_PN_LEN - j - 1];
517 /* Initialize AES key state here as an optimization so that
518 * it does not need to be initialized for every packet.
519 */
520 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
521 key_len);
522 if (IS_ERR(key->u.gcmp.tfm)) {
523 err = PTR_ERR(key->u.gcmp.tfm);
524 kfree(key);
525 return ERR_PTR(err);
526 }
527 break;
528 default:
529 if (cs) {
530 if (seq_len && seq_len != cs->pn_len) {
531 kfree(key);
532 return ERR_PTR(-EINVAL);
533 }
534
535 key->conf.iv_len = cs->hdr_len;
536 key->conf.icv_len = cs->mic_len;
537 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
538 for (j = 0; j < seq_len; j++)
539 key->u.gen.rx_pn[i][j] =
540 seq[seq_len - j - 1];
541 key->flags |= KEY_FLAG_CIPHER_SCHEME;
542 }
543 }
544 memcpy(key->conf.key, key_data, key_len);
545 INIT_LIST_HEAD(&key->list);
546
547 return key;
548 }
549
550 static void ieee80211_key_free_common(struct ieee80211_key *key)
551 {
552 switch (key->conf.cipher) {
553 case WLAN_CIPHER_SUITE_CCMP:
554 case WLAN_CIPHER_SUITE_CCMP_256:
555 ieee80211_aes_key_free(key->u.ccmp.tfm);
556 break;
557 case WLAN_CIPHER_SUITE_AES_CMAC:
558 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
559 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
560 break;
561 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
562 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
563 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
564 break;
565 case WLAN_CIPHER_SUITE_GCMP:
566 case WLAN_CIPHER_SUITE_GCMP_256:
567 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
568 break;
569 }
570 kzfree(key);
571 }
572
573 static void __ieee80211_key_destroy(struct ieee80211_key *key,
574 bool delay_tailroom)
575 {
576 if (key->local)
577 ieee80211_key_disable_hw_accel(key);
578
579 if (key->local) {
580 struct ieee80211_sub_if_data *sdata = key->sdata;
581
582 ieee80211_debugfs_key_remove(key);
583
584 if (delay_tailroom) {
585 /* see ieee80211_delayed_tailroom_dec */
586 sdata->crypto_tx_tailroom_pending_dec++;
587 schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
588 HZ/2);
589 } else {
590 decrease_tailroom_need_count(sdata, 1);
591 }
592 }
593
594 ieee80211_key_free_common(key);
595 }
596
597 static void ieee80211_key_destroy(struct ieee80211_key *key,
598 bool delay_tailroom)
599 {
600 if (!key)
601 return;
602
603 /*
604 * Synchronize so the TX path and rcu key iterators
605 * can no longer be using this key before we free/remove it.
606 */
607 synchronize_net();
608
609 __ieee80211_key_destroy(key, delay_tailroom);
610 }
611
612 void ieee80211_key_free_unused(struct ieee80211_key *key)
613 {
614 WARN_ON(key->sdata || key->local);
615 ieee80211_key_free_common(key);
616 }
617
618 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
619 struct ieee80211_key *old,
620 struct ieee80211_key *new)
621 {
622 u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
623 u8 *tk_old, *tk_new;
624
625 if (!old || new->conf.keylen != old->conf.keylen)
626 return false;
627
628 tk_old = old->conf.key;
629 tk_new = new->conf.key;
630
631 /*
632 * In station mode, don't compare the TX MIC key, as it's never used
633 * and offloaded rekeying may not care to send it to the host. This
634 * is the case in iwlwifi, for example.
635 */
636 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
637 new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
638 new->conf.keylen == WLAN_KEY_LEN_TKIP &&
639 !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
640 memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
641 memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
642 memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
643 memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
644 tk_old = tkip_old;
645 tk_new = tkip_new;
646 }
647
648 return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
649 }
650
651 int ieee80211_key_link(struct ieee80211_key *key,
652 struct ieee80211_sub_if_data *sdata,
653 struct sta_info *sta)
654 {
655 struct ieee80211_local *local = sdata->local;
656 struct ieee80211_key *old_key;
657 int idx, ret;
658 bool pairwise;
659
660 pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
661 idx = key->conf.keyidx;
662
663 mutex_lock(&sdata->local->key_mtx);
664
665 if (sta && pairwise)
666 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
667 else if (sta)
668 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
669 else
670 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
671
672 /*
673 * Silently accept key re-installation without really installing the
674 * new version of the key to avoid nonce reuse or replay issues.
675 */
676 if (ieee80211_key_identical(sdata, old_key, key)) {
677 ieee80211_key_free_unused(key);
678 ret = 0;
679 goto out;
680 }
681
682 key->local = sdata->local;
683 key->sdata = sdata;
684 key->sta = sta;
685
686 increment_tailroom_need_count(sdata);
687
688 ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
689 ieee80211_key_destroy(old_key, true);
690
691 ieee80211_debugfs_key_add(key);
692
693 if (!local->wowlan) {
694 ret = ieee80211_key_enable_hw_accel(key);
695 if (ret)
696 ieee80211_key_free(key, true);
697 } else {
698 ret = 0;
699 }
700
701 out:
702 mutex_unlock(&sdata->local->key_mtx);
703
704 return ret;
705 }
706
707 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
708 {
709 if (!key)
710 return;
711
712 /*
713 * Replace key with nothingness if it was ever used.
714 */
715 if (key->sdata)
716 ieee80211_key_replace(key->sdata, key->sta,
717 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
718 key, NULL);
719 ieee80211_key_destroy(key, delay_tailroom);
720 }
721
722 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
723 {
724 struct ieee80211_key *key;
725 struct ieee80211_sub_if_data *vlan;
726
727 ASSERT_RTNL();
728
729 if (WARN_ON(!ieee80211_sdata_running(sdata)))
730 return;
731
732 mutex_lock(&sdata->local->key_mtx);
733
734 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
735 sdata->crypto_tx_tailroom_pending_dec);
736
737 if (sdata->vif.type == NL80211_IFTYPE_AP) {
738 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
739 WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
740 vlan->crypto_tx_tailroom_pending_dec);
741 }
742
743 list_for_each_entry(key, &sdata->key_list, list) {
744 increment_tailroom_need_count(sdata);
745 ieee80211_key_enable_hw_accel(key);
746 }
747
748 mutex_unlock(&sdata->local->key_mtx);
749 }
750
751 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
752 {
753 struct ieee80211_sub_if_data *vlan;
754
755 mutex_lock(&sdata->local->key_mtx);
756
757 sdata->crypto_tx_tailroom_needed_cnt = 0;
758
759 if (sdata->vif.type == NL80211_IFTYPE_AP) {
760 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
761 vlan->crypto_tx_tailroom_needed_cnt = 0;
762 }
763
764 mutex_unlock(&sdata->local->key_mtx);
765 }
766
767 void ieee80211_iter_keys(struct ieee80211_hw *hw,
768 struct ieee80211_vif *vif,
769 void (*iter)(struct ieee80211_hw *hw,
770 struct ieee80211_vif *vif,
771 struct ieee80211_sta *sta,
772 struct ieee80211_key_conf *key,
773 void *data),
774 void *iter_data)
775 {
776 struct ieee80211_local *local = hw_to_local(hw);
777 struct ieee80211_key *key, *tmp;
778 struct ieee80211_sub_if_data *sdata;
779
780 ASSERT_RTNL();
781
782 mutex_lock(&local->key_mtx);
783 if (vif) {
784 sdata = vif_to_sdata(vif);
785 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
786 iter(hw, &sdata->vif,
787 key->sta ? &key->sta->sta : NULL,
788 &key->conf, iter_data);
789 } else {
790 list_for_each_entry(sdata, &local->interfaces, list)
791 list_for_each_entry_safe(key, tmp,
792 &sdata->key_list, list)
793 iter(hw, &sdata->vif,
794 key->sta ? &key->sta->sta : NULL,
795 &key->conf, iter_data);
796 }
797 mutex_unlock(&local->key_mtx);
798 }
799 EXPORT_SYMBOL(ieee80211_iter_keys);
800
801 static void
802 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
803 struct ieee80211_sub_if_data *sdata,
804 void (*iter)(struct ieee80211_hw *hw,
805 struct ieee80211_vif *vif,
806 struct ieee80211_sta *sta,
807 struct ieee80211_key_conf *key,
808 void *data),
809 void *iter_data)
810 {
811 struct ieee80211_key *key;
812
813 list_for_each_entry_rcu(key, &sdata->key_list, list) {
814 /* skip keys of station in removal process */
815 if (key->sta && key->sta->removed)
816 continue;
817 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
818 continue;
819
820 iter(hw, &sdata->vif,
821 key->sta ? &key->sta->sta : NULL,
822 &key->conf, iter_data);
823 }
824 }
825
826 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
827 struct ieee80211_vif *vif,
828 void (*iter)(struct ieee80211_hw *hw,
829 struct ieee80211_vif *vif,
830 struct ieee80211_sta *sta,
831 struct ieee80211_key_conf *key,
832 void *data),
833 void *iter_data)
834 {
835 struct ieee80211_local *local = hw_to_local(hw);
836 struct ieee80211_sub_if_data *sdata;
837
838 if (vif) {
839 sdata = vif_to_sdata(vif);
840 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
841 } else {
842 list_for_each_entry_rcu(sdata, &local->interfaces, list)
843 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
844 }
845 }
846 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
847
848 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
849 struct list_head *keys)
850 {
851 struct ieee80211_key *key, *tmp;
852
853 decrease_tailroom_need_count(sdata,
854 sdata->crypto_tx_tailroom_pending_dec);
855 sdata->crypto_tx_tailroom_pending_dec = 0;
856
857 ieee80211_debugfs_key_remove_mgmt_default(sdata);
858
859 list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
860 ieee80211_key_replace(key->sdata, key->sta,
861 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
862 key, NULL);
863 list_add_tail(&key->list, keys);
864 }
865
866 ieee80211_debugfs_key_update_default(sdata);
867 }
868
869 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
870 bool force_synchronize)
871 {
872 struct ieee80211_local *local = sdata->local;
873 struct ieee80211_sub_if_data *vlan;
874 struct ieee80211_sub_if_data *master;
875 struct ieee80211_key *key, *tmp;
876 LIST_HEAD(keys);
877
878 cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
879
880 mutex_lock(&local->key_mtx);
881
882 ieee80211_free_keys_iface(sdata, &keys);
883
884 if (sdata->vif.type == NL80211_IFTYPE_AP) {
885 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
886 ieee80211_free_keys_iface(vlan, &keys);
887 }
888
889 if (!list_empty(&keys) || force_synchronize)
890 synchronize_net();
891 list_for_each_entry_safe(key, tmp, &keys, list)
892 __ieee80211_key_destroy(key, false);
893
894 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
895 if (sdata->bss) {
896 master = container_of(sdata->bss,
897 struct ieee80211_sub_if_data,
898 u.ap);
899
900 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
901 master->crypto_tx_tailroom_needed_cnt);
902 }
903 } else {
904 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
905 sdata->crypto_tx_tailroom_pending_dec);
906 }
907
908 if (sdata->vif.type == NL80211_IFTYPE_AP) {
909 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
910 WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
911 vlan->crypto_tx_tailroom_pending_dec);
912 }
913
914 mutex_unlock(&local->key_mtx);
915 }
916
917 void ieee80211_free_sta_keys(struct ieee80211_local *local,
918 struct sta_info *sta)
919 {
920 struct ieee80211_key *key;
921 int i;
922
923 mutex_lock(&local->key_mtx);
924 for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
925 key = key_mtx_dereference(local, sta->gtk[i]);
926 if (!key)
927 continue;
928 ieee80211_key_replace(key->sdata, key->sta,
929 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
930 key, NULL);
931 __ieee80211_key_destroy(key, true);
932 }
933
934 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
935 key = key_mtx_dereference(local, sta->ptk[i]);
936 if (!key)
937 continue;
938 ieee80211_key_replace(key->sdata, key->sta,
939 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
940 key, NULL);
941 __ieee80211_key_destroy(key, true);
942 }
943
944 mutex_unlock(&local->key_mtx);
945 }
946
947 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
948 {
949 struct ieee80211_sub_if_data *sdata;
950
951 sdata = container_of(wk, struct ieee80211_sub_if_data,
952 dec_tailroom_needed_wk.work);
953
954 /*
955 * The reason for the delayed tailroom needed decrementing is to
956 * make roaming faster: during roaming, all keys are first deleted
957 * and then new keys are installed. The first new key causes the
958 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
959 * the cost of synchronize_net() (which can be slow). Avoid this
960 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
961 * key removal for a while, so if we roam the value is larger than
962 * zero and no 0->1 transition happens.
963 *
964 * The cost is that if the AP switching was from an AP with keys
965 * to one without, we still allocate tailroom while it would no
966 * longer be needed. However, in the typical (fast) roaming case
967 * within an ESS this usually won't happen.
968 */
969
970 mutex_lock(&sdata->local->key_mtx);
971 decrease_tailroom_need_count(sdata,
972 sdata->crypto_tx_tailroom_pending_dec);
973 sdata->crypto_tx_tailroom_pending_dec = 0;
974 mutex_unlock(&sdata->local->key_mtx);
975 }
976
977 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
978 const u8 *replay_ctr, gfp_t gfp)
979 {
980 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
981
982 trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
983
984 cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
985 }
986 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
987
988 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
989 int tid, struct ieee80211_key_seq *seq)
990 {
991 struct ieee80211_key *key;
992 const u8 *pn;
993
994 key = container_of(keyconf, struct ieee80211_key, conf);
995
996 switch (key->conf.cipher) {
997 case WLAN_CIPHER_SUITE_TKIP:
998 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
999 return;
1000 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1001 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1002 break;
1003 case WLAN_CIPHER_SUITE_CCMP:
1004 case WLAN_CIPHER_SUITE_CCMP_256:
1005 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1006 return;
1007 if (tid < 0)
1008 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1009 else
1010 pn = key->u.ccmp.rx_pn[tid];
1011 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1012 break;
1013 case WLAN_CIPHER_SUITE_AES_CMAC:
1014 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1015 if (WARN_ON(tid != 0))
1016 return;
1017 pn = key->u.aes_cmac.rx_pn;
1018 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1019 break;
1020 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1021 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1022 if (WARN_ON(tid != 0))
1023 return;
1024 pn = key->u.aes_gmac.rx_pn;
1025 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1026 break;
1027 case WLAN_CIPHER_SUITE_GCMP:
1028 case WLAN_CIPHER_SUITE_GCMP_256:
1029 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1030 return;
1031 if (tid < 0)
1032 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1033 else
1034 pn = key->u.gcmp.rx_pn[tid];
1035 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1036 break;
1037 }
1038 }
1039 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1040
1041 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1042 int tid, struct ieee80211_key_seq *seq)
1043 {
1044 struct ieee80211_key *key;
1045 u8 *pn;
1046
1047 key = container_of(keyconf, struct ieee80211_key, conf);
1048
1049 switch (key->conf.cipher) {
1050 case WLAN_CIPHER_SUITE_TKIP:
1051 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1052 return;
1053 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1054 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1055 break;
1056 case WLAN_CIPHER_SUITE_CCMP:
1057 case WLAN_CIPHER_SUITE_CCMP_256:
1058 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1059 return;
1060 if (tid < 0)
1061 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1062 else
1063 pn = key->u.ccmp.rx_pn[tid];
1064 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1065 break;
1066 case WLAN_CIPHER_SUITE_AES_CMAC:
1067 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1068 if (WARN_ON(tid != 0))
1069 return;
1070 pn = key->u.aes_cmac.rx_pn;
1071 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1072 break;
1073 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1074 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1075 if (WARN_ON(tid != 0))
1076 return;
1077 pn = key->u.aes_gmac.rx_pn;
1078 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1079 break;
1080 case WLAN_CIPHER_SUITE_GCMP:
1081 case WLAN_CIPHER_SUITE_GCMP_256:
1082 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1083 return;
1084 if (tid < 0)
1085 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1086 else
1087 pn = key->u.gcmp.rx_pn[tid];
1088 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1089 break;
1090 default:
1091 WARN_ON(1);
1092 break;
1093 }
1094 }
1095 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1096
1097 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1098 {
1099 struct ieee80211_key *key;
1100
1101 key = container_of(keyconf, struct ieee80211_key, conf);
1102
1103 assert_key_lock(key->local);
1104
1105 /*
1106 * if key was uploaded, we assume the driver will/has remove(d)
1107 * it, so adjust bookkeeping accordingly
1108 */
1109 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1110 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1111
1112 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1113 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
1114 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1115 increment_tailroom_need_count(key->sdata);
1116 }
1117
1118 ieee80211_key_free(key, false);
1119 }
1120 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1121
1122 struct ieee80211_key_conf *
1123 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1124 struct ieee80211_key_conf *keyconf)
1125 {
1126 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1127 struct ieee80211_local *local = sdata->local;
1128 struct ieee80211_key *key;
1129 int err;
1130
1131 if (WARN_ON(!local->wowlan))
1132 return ERR_PTR(-EINVAL);
1133
1134 if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1135 return ERR_PTR(-EINVAL);
1136
1137 key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1138 keyconf->keylen, keyconf->key,
1139 0, NULL, NULL);
1140 if (IS_ERR(key))
1141 return ERR_CAST(key);
1142
1143 if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1144 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1145
1146 err = ieee80211_key_link(key, sdata, NULL);
1147 if (err)
1148 return ERR_PTR(err);
1149
1150 return &key->conf;
1151 }
1152 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
CRIS linux kernel tree