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Linux 4.19.133
[linux/fpc-iii.git] / net / mac80211 / key.c
blobf20bb39f492da989675ea2a4137cca056ac81689
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 = key->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 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
166 /*
167 * The driver doesn't know anything about VLAN interfaces.
168 * Hence, don't send GTKs for VLAN interfaces to the driver.
169 */
170 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
171 ret = 1;
172 goto out_unsupported;
173 }
174 }
175
176 ret = drv_set_key(key->local, SET_KEY, sdata,
177 sta ? &sta->sta : NULL, &key->conf);
178
179 if (!ret) {
180 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
181
182 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
183 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
184 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
185 decrease_tailroom_need_count(sdata, 1);
186
187 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
188 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
189
190 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
191 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
192
193 return 0;
194 }
195
196 if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
197 sdata_err(sdata,
198 "failed to set key (%d, %pM) to hardware (%d)\n",
199 key->conf.keyidx,
200 sta ? sta->sta.addr : bcast_addr, ret);
201
202 out_unsupported:
203 switch (key->conf.cipher) {
204 case WLAN_CIPHER_SUITE_WEP40:
205 case WLAN_CIPHER_SUITE_WEP104:
206 case WLAN_CIPHER_SUITE_TKIP:
207 case WLAN_CIPHER_SUITE_CCMP:
208 case WLAN_CIPHER_SUITE_CCMP_256:
209 case WLAN_CIPHER_SUITE_AES_CMAC:
210 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
211 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
212 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
213 case WLAN_CIPHER_SUITE_GCMP:
214 case WLAN_CIPHER_SUITE_GCMP_256:
215 /* all of these we can do in software - if driver can */
216 if (ret == 1)
217 return 0;
218 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
219 return -EINVAL;
220 return 0;
221 default:
222 return -EINVAL;
223 }
224 }
225
226 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
227 {
228 struct ieee80211_sub_if_data *sdata;
229 struct sta_info *sta;
230 int ret;
231
232 might_sleep();
233
234 if (!key || !key->local->ops->set_key)
235 return;
236
237 assert_key_lock(key->local);
238
239 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
240 return;
241
242 sta = key->sta;
243 sdata = key->sdata;
244
245 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
246 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
247 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
248 increment_tailroom_need_count(sdata);
249
250 ret = drv_set_key(key->local, DISABLE_KEY, sdata,
251 sta ? &sta->sta : NULL, &key->conf);
252
253 if (ret)
254 sdata_err(sdata,
255 "failed to remove key (%d, %pM) from hardware (%d)\n",
256 key->conf.keyidx,
257 sta ? sta->sta.addr : bcast_addr, ret);
258
259 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
260 }
261
262 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
263 int idx, bool uni, bool multi)
264 {
265 struct ieee80211_key *key = NULL;
266
267 assert_key_lock(sdata->local);
268
269 if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
270 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
271
272 if (uni) {
273 rcu_assign_pointer(sdata->default_unicast_key, key);
274 ieee80211_check_fast_xmit_iface(sdata);
275 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
276 drv_set_default_unicast_key(sdata->local, sdata, idx);
277 }
278
279 if (multi)
280 rcu_assign_pointer(sdata->default_multicast_key, key);
281
282 ieee80211_debugfs_key_update_default(sdata);
283 }
284
285 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
286 bool uni, bool multi)
287 {
288 mutex_lock(&sdata->local->key_mtx);
289 __ieee80211_set_default_key(sdata, idx, uni, multi);
290 mutex_unlock(&sdata->local->key_mtx);
291 }
292
293 static void
294 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
295 {
296 struct ieee80211_key *key = NULL;
297
298 assert_key_lock(sdata->local);
299
300 if (idx >= NUM_DEFAULT_KEYS &&
301 idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
302 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
303
304 rcu_assign_pointer(sdata->default_mgmt_key, key);
305
306 ieee80211_debugfs_key_update_default(sdata);
307 }
308
309 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
310 int idx)
311 {
312 mutex_lock(&sdata->local->key_mtx);
313 __ieee80211_set_default_mgmt_key(sdata, idx);
314 mutex_unlock(&sdata->local->key_mtx);
315 }
316
317
318 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
319 struct sta_info *sta,
320 bool pairwise,
321 struct ieee80211_key *old,
322 struct ieee80211_key *new)
323 {
324 int idx;
325 bool defunikey, defmultikey, defmgmtkey;
326
327 /* caller must provide at least one old/new */
328 if (WARN_ON(!new && !old))
329 return;
330
331 if (new)
332 list_add_tail_rcu(&new->list, &sdata->key_list);
333
334 WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
335
336 if (old)
337 idx = old->conf.keyidx;
338 else
339 idx = new->conf.keyidx;
340
341 if (sta) {
342 if (pairwise) {
343 rcu_assign_pointer(sta->ptk[idx], new);
344 sta->ptk_idx = idx;
345 ieee80211_check_fast_xmit(sta);
346 } else {
347 rcu_assign_pointer(sta->gtk[idx], new);
348 }
349 ieee80211_check_fast_rx(sta);
350 } else {
351 defunikey = old &&
352 old == key_mtx_dereference(sdata->local,
353 sdata->default_unicast_key);
354 defmultikey = old &&
355 old == key_mtx_dereference(sdata->local,
356 sdata->default_multicast_key);
357 defmgmtkey = old &&
358 old == key_mtx_dereference(sdata->local,
359 sdata->default_mgmt_key);
360
361 if (defunikey && !new)
362 __ieee80211_set_default_key(sdata, -1, true, false);
363 if (defmultikey && !new)
364 __ieee80211_set_default_key(sdata, -1, false, true);
365 if (defmgmtkey && !new)
366 __ieee80211_set_default_mgmt_key(sdata, -1);
367
368 rcu_assign_pointer(sdata->keys[idx], new);
369 if (defunikey && new)
370 __ieee80211_set_default_key(sdata, new->conf.keyidx,
371 true, false);
372 if (defmultikey && new)
373 __ieee80211_set_default_key(sdata, new->conf.keyidx,
374 false, true);
375 if (defmgmtkey && new)
376 __ieee80211_set_default_mgmt_key(sdata,
377 new->conf.keyidx);
378 }
379
380 if (old)
381 list_del_rcu(&old->list);
382 }
383
384 struct ieee80211_key *
385 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
386 const u8 *key_data,
387 size_t seq_len, const u8 *seq,
388 const struct ieee80211_cipher_scheme *cs)
389 {
390 struct ieee80211_key *key;
391 int i, j, err;
392
393 if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
394 return ERR_PTR(-EINVAL);
395
396 key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
397 if (!key)
398 return ERR_PTR(-ENOMEM);
399
400 /*
401 * Default to software encryption; we'll later upload the
402 * key to the hardware if possible.
403 */
404 key->conf.flags = 0;
405 key->flags = 0;
406
407 key->conf.cipher = cipher;
408 key->conf.keyidx = idx;
409 key->conf.keylen = key_len;
410 switch (cipher) {
411 case WLAN_CIPHER_SUITE_WEP40:
412 case WLAN_CIPHER_SUITE_WEP104:
413 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
414 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
415 break;
416 case WLAN_CIPHER_SUITE_TKIP:
417 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
418 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
419 if (seq) {
420 for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
421 key->u.tkip.rx[i].iv32 =
422 get_unaligned_le32(&seq[2]);
423 key->u.tkip.rx[i].iv16 =
424 get_unaligned_le16(seq);
425 }
426 }
427 spin_lock_init(&key->u.tkip.txlock);
428 break;
429 case WLAN_CIPHER_SUITE_CCMP:
430 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
431 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
432 if (seq) {
433 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
434 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
435 key->u.ccmp.rx_pn[i][j] =
436 seq[IEEE80211_CCMP_PN_LEN - j - 1];
437 }
438 /*
439 * Initialize AES key state here as an optimization so that
440 * it does not need to be initialized for every packet.
441 */
442 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
443 key_data, key_len, IEEE80211_CCMP_MIC_LEN);
444 if (IS_ERR(key->u.ccmp.tfm)) {
445 err = PTR_ERR(key->u.ccmp.tfm);
446 kfree(key);
447 return ERR_PTR(err);
448 }
449 break;
450 case WLAN_CIPHER_SUITE_CCMP_256:
451 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
452 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
453 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
454 for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
455 key->u.ccmp.rx_pn[i][j] =
456 seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
457 /* Initialize AES key state here as an optimization so that
458 * it does not need to be initialized for every packet.
459 */
460 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
461 key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
462 if (IS_ERR(key->u.ccmp.tfm)) {
463 err = PTR_ERR(key->u.ccmp.tfm);
464 kfree(key);
465 return ERR_PTR(err);
466 }
467 break;
468 case WLAN_CIPHER_SUITE_AES_CMAC:
469 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
470 key->conf.iv_len = 0;
471 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
472 key->conf.icv_len = sizeof(struct ieee80211_mmie);
473 else
474 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
475 if (seq)
476 for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
477 key->u.aes_cmac.rx_pn[j] =
478 seq[IEEE80211_CMAC_PN_LEN - j - 1];
479 /*
480 * Initialize AES key state here as an optimization so that
481 * it does not need to be initialized for every packet.
482 */
483 key->u.aes_cmac.tfm =
484 ieee80211_aes_cmac_key_setup(key_data, key_len);
485 if (IS_ERR(key->u.aes_cmac.tfm)) {
486 err = PTR_ERR(key->u.aes_cmac.tfm);
487 kfree(key);
488 return ERR_PTR(err);
489 }
490 break;
491 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
492 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
493 key->conf.iv_len = 0;
494 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
495 if (seq)
496 for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
497 key->u.aes_gmac.rx_pn[j] =
498 seq[IEEE80211_GMAC_PN_LEN - j - 1];
499 /* Initialize AES key state here as an optimization so that
500 * it does not need to be initialized for every packet.
501 */
502 key->u.aes_gmac.tfm =
503 ieee80211_aes_gmac_key_setup(key_data, key_len);
504 if (IS_ERR(key->u.aes_gmac.tfm)) {
505 err = PTR_ERR(key->u.aes_gmac.tfm);
506 kfree(key);
507 return ERR_PTR(err);
508 }
509 break;
510 case WLAN_CIPHER_SUITE_GCMP:
511 case WLAN_CIPHER_SUITE_GCMP_256:
512 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
513 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
514 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
515 for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
516 key->u.gcmp.rx_pn[i][j] =
517 seq[IEEE80211_GCMP_PN_LEN - j - 1];
518 /* Initialize AES key state here as an optimization so that
519 * it does not need to be initialized for every packet.
520 */
521 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
522 key_len);
523 if (IS_ERR(key->u.gcmp.tfm)) {
524 err = PTR_ERR(key->u.gcmp.tfm);
525 kfree(key);
526 return ERR_PTR(err);
527 }
528 break;
529 default:
530 if (cs) {
531 if (seq_len && seq_len != cs->pn_len) {
532 kfree(key);
533 return ERR_PTR(-EINVAL);
534 }
535
536 key->conf.iv_len = cs->hdr_len;
537 key->conf.icv_len = cs->mic_len;
538 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
539 for (j = 0; j < seq_len; j++)
540 key->u.gen.rx_pn[i][j] =
541 seq[seq_len - j - 1];
542 key->flags |= KEY_FLAG_CIPHER_SCHEME;
543 }
544 }
545 memcpy(key->conf.key, key_data, key_len);
546 INIT_LIST_HEAD(&key->list);
547
548 return key;
549 }
550
551 static void ieee80211_key_free_common(struct ieee80211_key *key)
552 {
553 switch (key->conf.cipher) {
554 case WLAN_CIPHER_SUITE_CCMP:
555 case WLAN_CIPHER_SUITE_CCMP_256:
556 ieee80211_aes_key_free(key->u.ccmp.tfm);
557 break;
558 case WLAN_CIPHER_SUITE_AES_CMAC:
559 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
560 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
561 break;
562 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
563 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
564 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
565 break;
566 case WLAN_CIPHER_SUITE_GCMP:
567 case WLAN_CIPHER_SUITE_GCMP_256:
568 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
569 break;
570 }
571 kzfree(key);
572 }
573
574 static void __ieee80211_key_destroy(struct ieee80211_key *key,
575 bool delay_tailroom)
576 {
577 if (key->local)
578 ieee80211_key_disable_hw_accel(key);
579
580 if (key->local) {
581 struct ieee80211_sub_if_data *sdata = key->sdata;
582
583 ieee80211_debugfs_key_remove(key);
584
585 if (delay_tailroom) {
586 /* see ieee80211_delayed_tailroom_dec */
587 sdata->crypto_tx_tailroom_pending_dec++;
588 schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
589 HZ/2);
590 } else {
591 decrease_tailroom_need_count(sdata, 1);
592 }
593 }
594
595 ieee80211_key_free_common(key);
596 }
597
598 static void ieee80211_key_destroy(struct ieee80211_key *key,
599 bool delay_tailroom)
600 {
601 if (!key)
602 return;
603
604 /*
605 * Synchronize so the TX path and rcu key iterators
606 * can no longer be using this key before we free/remove it.
607 */
608 synchronize_net();
609
610 __ieee80211_key_destroy(key, delay_tailroom);
611 }
612
613 void ieee80211_key_free_unused(struct ieee80211_key *key)
614 {
615 WARN_ON(key->sdata || key->local);
616 ieee80211_key_free_common(key);
617 }
618
619 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
620 struct ieee80211_key *old,
621 struct ieee80211_key *new)
622 {
623 u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
624 u8 *tk_old, *tk_new;
625
626 if (!old || new->conf.keylen != old->conf.keylen)
627 return false;
628
629 tk_old = old->conf.key;
630 tk_new = new->conf.key;
631
632 /*
633 * In station mode, don't compare the TX MIC key, as it's never used
634 * and offloaded rekeying may not care to send it to the host. This
635 * is the case in iwlwifi, for example.
636 */
637 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
638 new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
639 new->conf.keylen == WLAN_KEY_LEN_TKIP &&
640 !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
641 memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
642 memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
643 memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
644 memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
645 tk_old = tkip_old;
646 tk_new = tkip_new;
647 }
648
649 return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
650 }
651
652 int ieee80211_key_link(struct ieee80211_key *key,
653 struct ieee80211_sub_if_data *sdata,
654 struct sta_info *sta)
655 {
656 struct ieee80211_local *local = sdata->local;
657 struct ieee80211_key *old_key;
658 int idx = key->conf.keyidx;
659 bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
660 /*
661 * We want to delay tailroom updates only for station - in that
662 * case it helps roaming speed, but in other cases it hurts and
663 * can cause warnings to appear.
664 */
665 bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
666 int ret;
667
668 mutex_lock(&sdata->local->key_mtx);
669
670 if (sta && pairwise)
671 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
672 else if (sta)
673 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
674 else
675 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
676
677 /*
678 * Silently accept key re-installation without really installing the
679 * new version of the key to avoid nonce reuse or replay issues.
680 */
681 if (ieee80211_key_identical(sdata, old_key, key)) {
682 ieee80211_key_free_unused(key);
683 ret = 0;
684 goto out;
685 }
686
687 key->local = sdata->local;
688 key->sdata = sdata;
689 key->sta = sta;
690
691 increment_tailroom_need_count(sdata);
692
693 ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
694 ieee80211_key_destroy(old_key, delay_tailroom);
695
696 ieee80211_debugfs_key_add(key);
697
698 if (!local->wowlan) {
699 ret = ieee80211_key_enable_hw_accel(key);
700 if (ret)
701 ieee80211_key_free(key, delay_tailroom);
702 } else {
703 ret = 0;
704 }
705
706 out:
707 mutex_unlock(&sdata->local->key_mtx);
708
709 return ret;
710 }
711
712 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
713 {
714 if (!key)
715 return;
716
717 /*
718 * Replace key with nothingness if it was ever used.
719 */
720 if (key->sdata)
721 ieee80211_key_replace(key->sdata, key->sta,
722 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
723 key, NULL);
724 ieee80211_key_destroy(key, delay_tailroom);
725 }
726
727 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
728 {
729 struct ieee80211_key *key;
730 struct ieee80211_sub_if_data *vlan;
731
732 ASSERT_RTNL();
733
734 if (WARN_ON(!ieee80211_sdata_running(sdata)))
735 return;
736
737 mutex_lock(&sdata->local->key_mtx);
738
739 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
740 sdata->crypto_tx_tailroom_pending_dec);
741
742 if (sdata->vif.type == NL80211_IFTYPE_AP) {
743 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
744 WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
745 vlan->crypto_tx_tailroom_pending_dec);
746 }
747
748 list_for_each_entry(key, &sdata->key_list, list) {
749 increment_tailroom_need_count(sdata);
750 ieee80211_key_enable_hw_accel(key);
751 }
752
753 mutex_unlock(&sdata->local->key_mtx);
754 }
755
756 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
757 {
758 struct ieee80211_sub_if_data *vlan;
759
760 mutex_lock(&sdata->local->key_mtx);
761
762 sdata->crypto_tx_tailroom_needed_cnt = 0;
763
764 if (sdata->vif.type == NL80211_IFTYPE_AP) {
765 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
766 vlan->crypto_tx_tailroom_needed_cnt = 0;
767 }
768
769 mutex_unlock(&sdata->local->key_mtx);
770 }
771
772 void ieee80211_iter_keys(struct ieee80211_hw *hw,
773 struct ieee80211_vif *vif,
774 void (*iter)(struct ieee80211_hw *hw,
775 struct ieee80211_vif *vif,
776 struct ieee80211_sta *sta,
777 struct ieee80211_key_conf *key,
778 void *data),
779 void *iter_data)
780 {
781 struct ieee80211_local *local = hw_to_local(hw);
782 struct ieee80211_key *key, *tmp;
783 struct ieee80211_sub_if_data *sdata;
784
785 ASSERT_RTNL();
786
787 mutex_lock(&local->key_mtx);
788 if (vif) {
789 sdata = vif_to_sdata(vif);
790 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
791 iter(hw, &sdata->vif,
792 key->sta ? &key->sta->sta : NULL,
793 &key->conf, iter_data);
794 } else {
795 list_for_each_entry(sdata, &local->interfaces, list)
796 list_for_each_entry_safe(key, tmp,
797 &sdata->key_list, list)
798 iter(hw, &sdata->vif,
799 key->sta ? &key->sta->sta : NULL,
800 &key->conf, iter_data);
801 }
802 mutex_unlock(&local->key_mtx);
803 }
804 EXPORT_SYMBOL(ieee80211_iter_keys);
805
806 static void
807 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
808 struct ieee80211_sub_if_data *sdata,
809 void (*iter)(struct ieee80211_hw *hw,
810 struct ieee80211_vif *vif,
811 struct ieee80211_sta *sta,
812 struct ieee80211_key_conf *key,
813 void *data),
814 void *iter_data)
815 {
816 struct ieee80211_key *key;
817
818 list_for_each_entry_rcu(key, &sdata->key_list, list) {
819 /* skip keys of station in removal process */
820 if (key->sta && key->sta->removed)
821 continue;
822 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
823 continue;
824
825 iter(hw, &sdata->vif,
826 key->sta ? &key->sta->sta : NULL,
827 &key->conf, iter_data);
828 }
829 }
830
831 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
832 struct ieee80211_vif *vif,
833 void (*iter)(struct ieee80211_hw *hw,
834 struct ieee80211_vif *vif,
835 struct ieee80211_sta *sta,
836 struct ieee80211_key_conf *key,
837 void *data),
838 void *iter_data)
839 {
840 struct ieee80211_local *local = hw_to_local(hw);
841 struct ieee80211_sub_if_data *sdata;
842
843 if (vif) {
844 sdata = vif_to_sdata(vif);
845 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
846 } else {
847 list_for_each_entry_rcu(sdata, &local->interfaces, list)
848 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
849 }
850 }
851 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
852
853 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
854 struct list_head *keys)
855 {
856 struct ieee80211_key *key, *tmp;
857
858 decrease_tailroom_need_count(sdata,
859 sdata->crypto_tx_tailroom_pending_dec);
860 sdata->crypto_tx_tailroom_pending_dec = 0;
861
862 ieee80211_debugfs_key_remove_mgmt_default(sdata);
863
864 list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
865 ieee80211_key_replace(key->sdata, key->sta,
866 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
867 key, NULL);
868 list_add_tail(&key->list, keys);
869 }
870
871 ieee80211_debugfs_key_update_default(sdata);
872 }
873
874 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
875 bool force_synchronize)
876 {
877 struct ieee80211_local *local = sdata->local;
878 struct ieee80211_sub_if_data *vlan;
879 struct ieee80211_sub_if_data *master;
880 struct ieee80211_key *key, *tmp;
881 LIST_HEAD(keys);
882
883 cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
884
885 mutex_lock(&local->key_mtx);
886
887 ieee80211_free_keys_iface(sdata, &keys);
888
889 if (sdata->vif.type == NL80211_IFTYPE_AP) {
890 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
891 ieee80211_free_keys_iface(vlan, &keys);
892 }
893
894 if (!list_empty(&keys) || force_synchronize)
895 synchronize_net();
896 list_for_each_entry_safe(key, tmp, &keys, list)
897 __ieee80211_key_destroy(key, false);
898
899 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
900 if (sdata->bss) {
901 master = container_of(sdata->bss,
902 struct ieee80211_sub_if_data,
903 u.ap);
904
905 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
906 master->crypto_tx_tailroom_needed_cnt);
907 }
908 } else {
909 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
910 sdata->crypto_tx_tailroom_pending_dec);
911 }
912
913 if (sdata->vif.type == NL80211_IFTYPE_AP) {
914 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
915 WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
916 vlan->crypto_tx_tailroom_pending_dec);
917 }
918
919 mutex_unlock(&local->key_mtx);
920 }
921
922 void ieee80211_free_sta_keys(struct ieee80211_local *local,
923 struct sta_info *sta)
924 {
925 struct ieee80211_key *key;
926 int i;
927
928 mutex_lock(&local->key_mtx);
929 for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
930 key = key_mtx_dereference(local, sta->gtk[i]);
931 if (!key)
932 continue;
933 ieee80211_key_replace(key->sdata, key->sta,
934 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
935 key, NULL);
936 __ieee80211_key_destroy(key, key->sdata->vif.type ==
937 NL80211_IFTYPE_STATION);
938 }
939
940 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
941 key = key_mtx_dereference(local, sta->ptk[i]);
942 if (!key)
943 continue;
944 ieee80211_key_replace(key->sdata, key->sta,
945 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
946 key, NULL);
947 __ieee80211_key_destroy(key, key->sdata->vif.type ==
948 NL80211_IFTYPE_STATION);
949 }
950
951 mutex_unlock(&local->key_mtx);
952 }
953
954 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
955 {
956 struct ieee80211_sub_if_data *sdata;
957
958 sdata = container_of(wk, struct ieee80211_sub_if_data,
959 dec_tailroom_needed_wk.work);
960
961 /*
962 * The reason for the delayed tailroom needed decrementing is to
963 * make roaming faster: during roaming, all keys are first deleted
964 * and then new keys are installed. The first new key causes the
965 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
966 * the cost of synchronize_net() (which can be slow). Avoid this
967 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
968 * key removal for a while, so if we roam the value is larger than
969 * zero and no 0->1 transition happens.
970 *
971 * The cost is that if the AP switching was from an AP with keys
972 * to one without, we still allocate tailroom while it would no
973 * longer be needed. However, in the typical (fast) roaming case
974 * within an ESS this usually won't happen.
975 */
976
977 mutex_lock(&sdata->local->key_mtx);
978 decrease_tailroom_need_count(sdata,
979 sdata->crypto_tx_tailroom_pending_dec);
980 sdata->crypto_tx_tailroom_pending_dec = 0;
981 mutex_unlock(&sdata->local->key_mtx);
982 }
983
984 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
985 const u8 *replay_ctr, gfp_t gfp)
986 {
987 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
988
989 trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
990
991 cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
992 }
993 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
994
995 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
996 int tid, struct ieee80211_key_seq *seq)
997 {
998 struct ieee80211_key *key;
999 const u8 *pn;
1000
1001 key = container_of(keyconf, struct ieee80211_key, conf);
1002
1003 switch (key->conf.cipher) {
1004 case WLAN_CIPHER_SUITE_TKIP:
1005 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1006 return;
1007 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1008 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1009 break;
1010 case WLAN_CIPHER_SUITE_CCMP:
1011 case WLAN_CIPHER_SUITE_CCMP_256:
1012 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1013 return;
1014 if (tid < 0)
1015 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1016 else
1017 pn = key->u.ccmp.rx_pn[tid];
1018 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1019 break;
1020 case WLAN_CIPHER_SUITE_AES_CMAC:
1021 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1022 if (WARN_ON(tid != 0))
1023 return;
1024 pn = key->u.aes_cmac.rx_pn;
1025 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1026 break;
1027 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1028 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1029 if (WARN_ON(tid != 0))
1030 return;
1031 pn = key->u.aes_gmac.rx_pn;
1032 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1033 break;
1034 case WLAN_CIPHER_SUITE_GCMP:
1035 case WLAN_CIPHER_SUITE_GCMP_256:
1036 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1037 return;
1038 if (tid < 0)
1039 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1040 else
1041 pn = key->u.gcmp.rx_pn[tid];
1042 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1043 break;
1044 }
1045 }
1046 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1047
1048 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1049 int tid, struct ieee80211_key_seq *seq)
1050 {
1051 struct ieee80211_key *key;
1052 u8 *pn;
1053
1054 key = container_of(keyconf, struct ieee80211_key, conf);
1055
1056 switch (key->conf.cipher) {
1057 case WLAN_CIPHER_SUITE_TKIP:
1058 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1059 return;
1060 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1061 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1062 break;
1063 case WLAN_CIPHER_SUITE_CCMP:
1064 case WLAN_CIPHER_SUITE_CCMP_256:
1065 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1066 return;
1067 if (tid < 0)
1068 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1069 else
1070 pn = key->u.ccmp.rx_pn[tid];
1071 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1072 break;
1073 case WLAN_CIPHER_SUITE_AES_CMAC:
1074 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1075 if (WARN_ON(tid != 0))
1076 return;
1077 pn = key->u.aes_cmac.rx_pn;
1078 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1079 break;
1080 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1081 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1082 if (WARN_ON(tid != 0))
1083 return;
1084 pn = key->u.aes_gmac.rx_pn;
1085 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1086 break;
1087 case WLAN_CIPHER_SUITE_GCMP:
1088 case WLAN_CIPHER_SUITE_GCMP_256:
1089 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1090 return;
1091 if (tid < 0)
1092 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1093 else
1094 pn = key->u.gcmp.rx_pn[tid];
1095 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1096 break;
1097 default:
1098 WARN_ON(1);
1099 break;
1100 }
1101 }
1102 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1103
1104 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1105 {
1106 struct ieee80211_key *key;
1107
1108 key = container_of(keyconf, struct ieee80211_key, conf);
1109
1110 assert_key_lock(key->local);
1111
1112 /*
1113 * if key was uploaded, we assume the driver will/has remove(d)
1114 * it, so adjust bookkeeping accordingly
1115 */
1116 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1117 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1118
1119 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1120 IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
1121 (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1122 increment_tailroom_need_count(key->sdata);
1123 }
1124
1125 ieee80211_key_free(key, false);
1126 }
1127 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1128
1129 struct ieee80211_key_conf *
1130 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1131 struct ieee80211_key_conf *keyconf)
1132 {
1133 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1134 struct ieee80211_local *local = sdata->local;
1135 struct ieee80211_key *key;
1136 int err;
1137
1138 if (WARN_ON(!local->wowlan))
1139 return ERR_PTR(-EINVAL);
1140
1141 if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1142 return ERR_PTR(-EINVAL);
1143
1144 key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1145 keyconf->keylen, keyconf->key,
1146 0, NULL, NULL);
1147 if (IS_ERR(key))
1148 return ERR_CAST(key);
1149
1150 if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1151 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1152
1153 err = ieee80211_key_link(key, sdata, NULL);
1154 if (err)
1155 return ERR_PTR(err);
1156
1157 return &key->conf;
1158 }
1159 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
Linux with added FPC-III support