1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright 2002-2005, Instant802 Networks, Inc.
4 * Copyright 2005-2006, Devicescape Software, Inc.
5 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
6 * Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net>
7 * Copyright 2013-2014 Intel Mobile Communications GmbH
8 * Copyright 2015-2017 Intel Deutschland GmbH
9 * Copyright 2018-2020 Intel Corporation
12 #include <linux/if_ether.h>
13 #include <linux/etherdevice.h>
14 #include <linux/list.h>
15 #include <linux/rcupdate.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 #include <net/mac80211.h>
20 #include <crypto/algapi.h>
21 #include <asm/unaligned.h>
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
24 #include "debugfs_key.h"
32 * DOC: Key handling basics
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.
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.
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.
54 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
56 static void assert_key_lock(struct ieee80211_local *local)
58 lockdep_assert_held(&local->key_mtx);
62 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
64 struct ieee80211_sub_if_data *vlan;
66 if (sdata->vif.type != NL80211_IFTYPE_AP)
69 /* crypto_tx_tailroom_needed_cnt is protected by this */
70 assert_key_lock(sdata->local);
74 list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
75 vlan->crypto_tx_tailroom_needed_cnt += delta;
80 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
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:
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.
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
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)
97 * Solution has been explained at
98 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
101 assert_key_lock(sdata->local);
103 update_vlan_tailroom_need_count(sdata, 1);
105 if (!sdata->crypto_tx_tailroom_needed_cnt++) {
107 * Flush all XMIT packets currently using HW encryption or no
108 * encryption at all if the count transition is from 0 -> 1.
114 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
117 assert_key_lock(sdata->local);
119 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
121 update_vlan_tailroom_need_count(sdata, -delta);
122 sdata->crypto_tx_tailroom_needed_cnt -= delta;
125 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
127 struct ieee80211_sub_if_data *sdata = key->sdata;
128 struct sta_info *sta;
129 int ret = -EOPNOTSUPP;
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
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);
147 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
151 if (!key->local->ops->set_key)
152 goto out_unsupported;
154 assert_key_lock(key->local);
159 * If this is a per-STA GTK, check if it
160 * is supported; if not, return.
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;
166 if (sta && !sta->uploaded)
167 goto out_unsupported;
169 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
171 * The driver doesn't know anything about VLAN interfaces.
172 * Hence, don't send GTKs for VLAN interfaces to the driver.
174 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
176 goto out_unsupported;
180 ret = drv_set_key(key->local, SET_KEY, sdata,
181 sta ? &sta->sta : NULL, &key->conf);
184 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
186 if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
187 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
188 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
189 decrease_tailroom_need_count(sdata, 1);
191 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
192 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
194 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
195 (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
200 if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
202 "failed to set key (%d, %pM) to hardware (%d)\n",
204 sta ? sta->sta.addr : bcast_addr, ret);
207 switch (key->conf.cipher) {
208 case WLAN_CIPHER_SUITE_WEP40:
209 case WLAN_CIPHER_SUITE_WEP104:
210 case WLAN_CIPHER_SUITE_TKIP:
211 case WLAN_CIPHER_SUITE_CCMP:
212 case WLAN_CIPHER_SUITE_CCMP_256:
213 case WLAN_CIPHER_SUITE_GCMP:
214 case WLAN_CIPHER_SUITE_GCMP_256:
215 case WLAN_CIPHER_SUITE_AES_CMAC:
216 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
217 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
218 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
219 /* all of these we can do in software - if driver can */
222 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
230 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
232 struct ieee80211_sub_if_data *sdata;
233 struct sta_info *sta;
238 if (!key || !key->local->ops->set_key)
241 assert_key_lock(key->local);
243 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
249 if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
250 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
251 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
252 increment_tailroom_need_count(sdata);
254 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
255 ret = drv_set_key(key->local, DISABLE_KEY, sdata,
256 sta ? &sta->sta : NULL, &key->conf);
260 "failed to remove key (%d, %pM) from hardware (%d)\n",
262 sta ? sta->sta.addr : bcast_addr, ret);
265 static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force)
267 struct sta_info *sta = key->sta;
268 struct ieee80211_local *local = key->local;
270 assert_key_lock(local);
272 set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION);
274 sta->ptk_idx = key->conf.keyidx;
276 if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
277 clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
278 ieee80211_check_fast_xmit(sta);
283 int ieee80211_set_tx_key(struct ieee80211_key *key)
285 return _ieee80211_set_tx_key(key, false);
288 static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
289 struct ieee80211_key *new)
291 struct ieee80211_local *local = new->local;
292 struct sta_info *sta = new->sta;
295 assert_key_lock(local);
297 if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) {
298 /* Extended Key ID key install, initial one or rekey */
300 if (sta->ptk_idx != INVALID_PTK_KEYIDX &&
301 !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) {
302 /* Aggregation Sessions with Extended Key ID must not
303 * mix MPDUs with different keyIDs within one A-MPDU.
304 * Tear down running Tx aggregation sessions and block
305 * new Rx/Tx aggregation requests during rekey to
306 * ensure there are no A-MPDUs when the driver is not
307 * supporting A-MPDU key borders. (Blocking Tx only
308 * would be sufficient but WLAN_STA_BLOCK_BA gets the
309 * job done for the few ms we need it.)
311 set_sta_flag(sta, WLAN_STA_BLOCK_BA);
312 mutex_lock(&sta->ampdu_mlme.mtx);
313 for (i = 0; i < IEEE80211_NUM_TIDS; i++)
314 ___ieee80211_stop_tx_ba_session(sta, i,
315 AGG_STOP_LOCAL_REQUEST);
316 mutex_unlock(&sta->ampdu_mlme.mtx);
319 /* Rekey without Extended Key ID.
320 * Aggregation sessions are OK when running on SW crypto.
321 * A broken remote STA may cause issues not observed with HW
324 if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
327 /* Stop Tx till we are on the new key */
328 old->flags |= KEY_FLAG_TAINTED;
329 ieee80211_clear_fast_xmit(sta);
330 if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
331 set_sta_flag(sta, WLAN_STA_BLOCK_BA);
332 ieee80211_sta_tear_down_BA_sessions(sta,
333 AGG_STOP_LOCAL_REQUEST);
335 if (!wiphy_ext_feature_isset(local->hw.wiphy,
336 NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) {
337 pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.",
339 /* Flushing the driver queues *may* help prevent
340 * the clear text leaks and freezes.
342 ieee80211_flush_queues(local, old->sdata, false);
347 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
348 int idx, bool uni, bool multi)
350 struct ieee80211_key *key = NULL;
352 assert_key_lock(sdata->local);
354 if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
355 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
358 rcu_assign_pointer(sdata->default_unicast_key, key);
359 ieee80211_check_fast_xmit_iface(sdata);
360 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
361 drv_set_default_unicast_key(sdata->local, sdata, idx);
365 rcu_assign_pointer(sdata->default_multicast_key, key);
367 ieee80211_debugfs_key_update_default(sdata);
370 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
371 bool uni, bool multi)
373 mutex_lock(&sdata->local->key_mtx);
374 __ieee80211_set_default_key(sdata, idx, uni, multi);
375 mutex_unlock(&sdata->local->key_mtx);
379 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
381 struct ieee80211_key *key = NULL;
383 assert_key_lock(sdata->local);
385 if (idx >= NUM_DEFAULT_KEYS &&
386 idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
387 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
389 rcu_assign_pointer(sdata->default_mgmt_key, key);
391 ieee80211_debugfs_key_update_default(sdata);
394 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
397 mutex_lock(&sdata->local->key_mtx);
398 __ieee80211_set_default_mgmt_key(sdata, idx);
399 mutex_unlock(&sdata->local->key_mtx);
403 __ieee80211_set_default_beacon_key(struct ieee80211_sub_if_data *sdata, int idx)
405 struct ieee80211_key *key = NULL;
407 assert_key_lock(sdata->local);
409 if (idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS &&
410 idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
411 NUM_DEFAULT_BEACON_KEYS)
412 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
414 rcu_assign_pointer(sdata->default_beacon_key, key);
416 ieee80211_debugfs_key_update_default(sdata);
419 void ieee80211_set_default_beacon_key(struct ieee80211_sub_if_data *sdata,
422 mutex_lock(&sdata->local->key_mtx);
423 __ieee80211_set_default_beacon_key(sdata, idx);
424 mutex_unlock(&sdata->local->key_mtx);
427 static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
428 struct sta_info *sta,
430 struct ieee80211_key *old,
431 struct ieee80211_key *new)
435 bool defunikey, defmultikey, defmgmtkey, defbeaconkey;
437 /* caller must provide at least one old/new */
438 if (WARN_ON(!new && !old))
442 list_add_tail_rcu(&new->list, &sdata->key_list);
444 WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
446 if (new && sta && pairwise) {
447 /* Unicast rekey needs special handling. With Extended Key ID
448 * old is still NULL for the first rekey.
450 ieee80211_pairwise_rekey(old, new);
454 idx = old->conf.keyidx;
456 if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
457 ieee80211_key_disable_hw_accel(old);
460 ret = ieee80211_key_enable_hw_accel(new);
463 /* new must be provided in case old is not */
464 idx = new->conf.keyidx;
465 if (!new->local->wowlan)
466 ret = ieee80211_key_enable_hw_accel(new);
474 rcu_assign_pointer(sta->ptk[idx], new);
476 !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX))
477 _ieee80211_set_tx_key(new, true);
479 rcu_assign_pointer(sta->gtk[idx], new);
481 /* Only needed for transition from no key -> key.
482 * Still triggers unnecessary when using Extended Key ID
483 * and installing the second key ID the first time.
486 ieee80211_check_fast_rx(sta);
489 old == key_mtx_dereference(sdata->local,
490 sdata->default_unicast_key);
492 old == key_mtx_dereference(sdata->local,
493 sdata->default_multicast_key);
495 old == key_mtx_dereference(sdata->local,
496 sdata->default_mgmt_key);
497 defbeaconkey = old &&
498 old == key_mtx_dereference(sdata->local,
499 sdata->default_beacon_key);
501 if (defunikey && !new)
502 __ieee80211_set_default_key(sdata, -1, true, false);
503 if (defmultikey && !new)
504 __ieee80211_set_default_key(sdata, -1, false, true);
505 if (defmgmtkey && !new)
506 __ieee80211_set_default_mgmt_key(sdata, -1);
507 if (defbeaconkey && !new)
508 __ieee80211_set_default_beacon_key(sdata, -1);
510 rcu_assign_pointer(sdata->keys[idx], new);
511 if (defunikey && new)
512 __ieee80211_set_default_key(sdata, new->conf.keyidx,
514 if (defmultikey && new)
515 __ieee80211_set_default_key(sdata, new->conf.keyidx,
517 if (defmgmtkey && new)
518 __ieee80211_set_default_mgmt_key(sdata,
520 if (defbeaconkey && new)
521 __ieee80211_set_default_beacon_key(sdata,
526 list_del_rcu(&old->list);
531 struct ieee80211_key *
532 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
534 size_t seq_len, const u8 *seq,
535 const struct ieee80211_cipher_scheme *cs)
537 struct ieee80211_key *key;
540 if (WARN_ON(idx < 0 ||
541 idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
542 NUM_DEFAULT_BEACON_KEYS))
543 return ERR_PTR(-EINVAL);
545 key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
547 return ERR_PTR(-ENOMEM);
550 * Default to software encryption; we'll later upload the
551 * key to the hardware if possible.
556 key->conf.cipher = cipher;
557 key->conf.keyidx = idx;
558 key->conf.keylen = key_len;
560 case WLAN_CIPHER_SUITE_WEP40:
561 case WLAN_CIPHER_SUITE_WEP104:
562 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
563 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
565 case WLAN_CIPHER_SUITE_TKIP:
566 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
567 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
569 for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
570 key->u.tkip.rx[i].iv32 =
571 get_unaligned_le32(&seq[2]);
572 key->u.tkip.rx[i].iv16 =
573 get_unaligned_le16(seq);
576 spin_lock_init(&key->u.tkip.txlock);
578 case WLAN_CIPHER_SUITE_CCMP:
579 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
580 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
582 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
583 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
584 key->u.ccmp.rx_pn[i][j] =
585 seq[IEEE80211_CCMP_PN_LEN - j - 1];
588 * Initialize AES key state here as an optimization so that
589 * it does not need to be initialized for every packet.
591 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
592 key_data, key_len, IEEE80211_CCMP_MIC_LEN);
593 if (IS_ERR(key->u.ccmp.tfm)) {
594 err = PTR_ERR(key->u.ccmp.tfm);
599 case WLAN_CIPHER_SUITE_CCMP_256:
600 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
601 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
602 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
603 for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
604 key->u.ccmp.rx_pn[i][j] =
605 seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
606 /* Initialize AES key state here as an optimization so that
607 * it does not need to be initialized for every packet.
609 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
610 key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
611 if (IS_ERR(key->u.ccmp.tfm)) {
612 err = PTR_ERR(key->u.ccmp.tfm);
617 case WLAN_CIPHER_SUITE_AES_CMAC:
618 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
619 key->conf.iv_len = 0;
620 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
621 key->conf.icv_len = sizeof(struct ieee80211_mmie);
623 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
625 for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
626 key->u.aes_cmac.rx_pn[j] =
627 seq[IEEE80211_CMAC_PN_LEN - j - 1];
629 * Initialize AES key state here as an optimization so that
630 * it does not need to be initialized for every packet.
632 key->u.aes_cmac.tfm =
633 ieee80211_aes_cmac_key_setup(key_data, key_len);
634 if (IS_ERR(key->u.aes_cmac.tfm)) {
635 err = PTR_ERR(key->u.aes_cmac.tfm);
640 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
641 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
642 key->conf.iv_len = 0;
643 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
645 for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
646 key->u.aes_gmac.rx_pn[j] =
647 seq[IEEE80211_GMAC_PN_LEN - j - 1];
648 /* Initialize AES key state here as an optimization so that
649 * it does not need to be initialized for every packet.
651 key->u.aes_gmac.tfm =
652 ieee80211_aes_gmac_key_setup(key_data, key_len);
653 if (IS_ERR(key->u.aes_gmac.tfm)) {
654 err = PTR_ERR(key->u.aes_gmac.tfm);
659 case WLAN_CIPHER_SUITE_GCMP:
660 case WLAN_CIPHER_SUITE_GCMP_256:
661 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
662 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
663 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
664 for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
665 key->u.gcmp.rx_pn[i][j] =
666 seq[IEEE80211_GCMP_PN_LEN - j - 1];
667 /* Initialize AES key state here as an optimization so that
668 * it does not need to be initialized for every packet.
670 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
672 if (IS_ERR(key->u.gcmp.tfm)) {
673 err = PTR_ERR(key->u.gcmp.tfm);
680 if (seq_len && seq_len != cs->pn_len) {
682 return ERR_PTR(-EINVAL);
685 key->conf.iv_len = cs->hdr_len;
686 key->conf.icv_len = cs->mic_len;
687 for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
688 for (j = 0; j < seq_len; j++)
689 key->u.gen.rx_pn[i][j] =
690 seq[seq_len - j - 1];
691 key->flags |= KEY_FLAG_CIPHER_SCHEME;
694 memcpy(key->conf.key, key_data, key_len);
695 INIT_LIST_HEAD(&key->list);
700 static void ieee80211_key_free_common(struct ieee80211_key *key)
702 switch (key->conf.cipher) {
703 case WLAN_CIPHER_SUITE_CCMP:
704 case WLAN_CIPHER_SUITE_CCMP_256:
705 ieee80211_aes_key_free(key->u.ccmp.tfm);
707 case WLAN_CIPHER_SUITE_AES_CMAC:
708 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
709 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
711 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
712 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
713 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
715 case WLAN_CIPHER_SUITE_GCMP:
716 case WLAN_CIPHER_SUITE_GCMP_256:
717 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
720 kfree_sensitive(key);
723 static void __ieee80211_key_destroy(struct ieee80211_key *key,
727 struct ieee80211_sub_if_data *sdata = key->sdata;
729 ieee80211_debugfs_key_remove(key);
731 if (delay_tailroom) {
732 /* see ieee80211_delayed_tailroom_dec */
733 sdata->crypto_tx_tailroom_pending_dec++;
734 schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
737 decrease_tailroom_need_count(sdata, 1);
741 ieee80211_key_free_common(key);
744 static void ieee80211_key_destroy(struct ieee80211_key *key,
751 * Synchronize so the TX path and rcu key iterators
752 * can no longer be using this key before we free/remove it.
756 __ieee80211_key_destroy(key, delay_tailroom);
759 void ieee80211_key_free_unused(struct ieee80211_key *key)
761 WARN_ON(key->sdata || key->local);
762 ieee80211_key_free_common(key);
765 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
766 struct ieee80211_key *old,
767 struct ieee80211_key *new)
769 u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
772 if (!old || new->conf.keylen != old->conf.keylen)
775 tk_old = old->conf.key;
776 tk_new = new->conf.key;
779 * In station mode, don't compare the TX MIC key, as it's never used
780 * and offloaded rekeying may not care to send it to the host. This
781 * is the case in iwlwifi, for example.
783 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
784 new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
785 new->conf.keylen == WLAN_KEY_LEN_TKIP &&
786 !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
787 memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
788 memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
789 memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
790 memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
795 return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
798 int ieee80211_key_link(struct ieee80211_key *key,
799 struct ieee80211_sub_if_data *sdata,
800 struct sta_info *sta)
802 static atomic_t key_color = ATOMIC_INIT(0);
803 struct ieee80211_key *old_key;
804 int idx = key->conf.keyidx;
805 bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
807 * We want to delay tailroom updates only for station - in that
808 * case it helps roaming speed, but in other cases it hurts and
809 * can cause warnings to appear.
811 bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
812 int ret = -EOPNOTSUPP;
814 mutex_lock(&sdata->local->key_mtx);
816 if (sta && pairwise) {
817 struct ieee80211_key *alt_key;
819 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
820 alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]);
822 /* The rekey code assumes that the old and new key are using
823 * the same cipher. Enforce the assumption for pairwise keys.
825 if ((alt_key && alt_key->conf.cipher != key->conf.cipher) ||
826 (old_key && old_key->conf.cipher != key->conf.cipher))
829 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
831 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
834 /* Non-pairwise keys must also not switch the cipher on rekey */
836 if (old_key && old_key->conf.cipher != key->conf.cipher)
841 * Silently accept key re-installation without really installing the
842 * new version of the key to avoid nonce reuse or replay issues.
844 if (ieee80211_key_identical(sdata, old_key, key)) {
845 ieee80211_key_free_unused(key);
850 key->local = sdata->local;
855 * Assign a unique ID to every key so we can easily prevent mixed
856 * key and fragment cache attacks.
858 key->color = atomic_inc_return(&key_color);
860 increment_tailroom_need_count(sdata);
862 ret = ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
865 ieee80211_debugfs_key_add(key);
866 ieee80211_key_destroy(old_key, delay_tailroom);
868 ieee80211_key_free(key, delay_tailroom);
872 mutex_unlock(&sdata->local->key_mtx);
877 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
883 * Replace key with nothingness if it was ever used.
886 ieee80211_key_replace(key->sdata, key->sta,
887 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
889 ieee80211_key_destroy(key, delay_tailroom);
892 void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata)
894 struct ieee80211_key *key;
895 struct ieee80211_sub_if_data *vlan;
899 mutex_lock(&sdata->local->key_mtx);
901 sdata->crypto_tx_tailroom_needed_cnt = 0;
902 sdata->crypto_tx_tailroom_pending_dec = 0;
904 if (sdata->vif.type == NL80211_IFTYPE_AP) {
905 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
906 vlan->crypto_tx_tailroom_needed_cnt = 0;
907 vlan->crypto_tx_tailroom_pending_dec = 0;
911 if (ieee80211_sdata_running(sdata)) {
912 list_for_each_entry(key, &sdata->key_list, list) {
913 increment_tailroom_need_count(sdata);
914 ieee80211_key_enable_hw_accel(key);
918 mutex_unlock(&sdata->local->key_mtx);
921 void ieee80211_iter_keys(struct ieee80211_hw *hw,
922 struct ieee80211_vif *vif,
923 void (*iter)(struct ieee80211_hw *hw,
924 struct ieee80211_vif *vif,
925 struct ieee80211_sta *sta,
926 struct ieee80211_key_conf *key,
930 struct ieee80211_local *local = hw_to_local(hw);
931 struct ieee80211_key *key, *tmp;
932 struct ieee80211_sub_if_data *sdata;
936 mutex_lock(&local->key_mtx);
938 sdata = vif_to_sdata(vif);
939 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
940 iter(hw, &sdata->vif,
941 key->sta ? &key->sta->sta : NULL,
942 &key->conf, iter_data);
944 list_for_each_entry(sdata, &local->interfaces, list)
945 list_for_each_entry_safe(key, tmp,
946 &sdata->key_list, list)
947 iter(hw, &sdata->vif,
948 key->sta ? &key->sta->sta : NULL,
949 &key->conf, iter_data);
951 mutex_unlock(&local->key_mtx);
953 EXPORT_SYMBOL(ieee80211_iter_keys);
956 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
957 struct ieee80211_sub_if_data *sdata,
958 void (*iter)(struct ieee80211_hw *hw,
959 struct ieee80211_vif *vif,
960 struct ieee80211_sta *sta,
961 struct ieee80211_key_conf *key,
965 struct ieee80211_key *key;
967 list_for_each_entry_rcu(key, &sdata->key_list, list) {
968 /* skip keys of station in removal process */
969 if (key->sta && key->sta->removed)
971 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
974 iter(hw, &sdata->vif,
975 key->sta ? &key->sta->sta : NULL,
976 &key->conf, iter_data);
980 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
981 struct ieee80211_vif *vif,
982 void (*iter)(struct ieee80211_hw *hw,
983 struct ieee80211_vif *vif,
984 struct ieee80211_sta *sta,
985 struct ieee80211_key_conf *key,
989 struct ieee80211_local *local = hw_to_local(hw);
990 struct ieee80211_sub_if_data *sdata;
993 sdata = vif_to_sdata(vif);
994 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
996 list_for_each_entry_rcu(sdata, &local->interfaces, list)
997 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
1000 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
1002 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
1003 struct list_head *keys)
1005 struct ieee80211_key *key, *tmp;
1007 decrease_tailroom_need_count(sdata,
1008 sdata->crypto_tx_tailroom_pending_dec);
1009 sdata->crypto_tx_tailroom_pending_dec = 0;
1011 ieee80211_debugfs_key_remove_mgmt_default(sdata);
1012 ieee80211_debugfs_key_remove_beacon_default(sdata);
1014 list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
1015 ieee80211_key_replace(key->sdata, key->sta,
1016 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1018 list_add_tail(&key->list, keys);
1021 ieee80211_debugfs_key_update_default(sdata);
1024 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
1025 bool force_synchronize)
1027 struct ieee80211_local *local = sdata->local;
1028 struct ieee80211_sub_if_data *vlan;
1029 struct ieee80211_sub_if_data *master;
1030 struct ieee80211_key *key, *tmp;
1033 cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
1035 mutex_lock(&local->key_mtx);
1037 ieee80211_free_keys_iface(sdata, &keys);
1039 if (sdata->vif.type == NL80211_IFTYPE_AP) {
1040 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1041 ieee80211_free_keys_iface(vlan, &keys);
1044 if (!list_empty(&keys) || force_synchronize)
1046 list_for_each_entry_safe(key, tmp, &keys, list)
1047 __ieee80211_key_destroy(key, false);
1049 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1051 master = container_of(sdata->bss,
1052 struct ieee80211_sub_if_data,
1055 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
1056 master->crypto_tx_tailroom_needed_cnt);
1059 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
1060 sdata->crypto_tx_tailroom_pending_dec);
1063 if (sdata->vif.type == NL80211_IFTYPE_AP) {
1064 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1065 WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
1066 vlan->crypto_tx_tailroom_pending_dec);
1069 mutex_unlock(&local->key_mtx);
1072 void ieee80211_free_sta_keys(struct ieee80211_local *local,
1073 struct sta_info *sta)
1075 struct ieee80211_key *key;
1078 mutex_lock(&local->key_mtx);
1079 for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
1080 key = key_mtx_dereference(local, sta->gtk[i]);
1083 ieee80211_key_replace(key->sdata, key->sta,
1084 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1086 __ieee80211_key_destroy(key, key->sdata->vif.type ==
1087 NL80211_IFTYPE_STATION);
1090 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1091 key = key_mtx_dereference(local, sta->ptk[i]);
1094 ieee80211_key_replace(key->sdata, key->sta,
1095 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
1097 __ieee80211_key_destroy(key, key->sdata->vif.type ==
1098 NL80211_IFTYPE_STATION);
1101 mutex_unlock(&local->key_mtx);
1104 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
1106 struct ieee80211_sub_if_data *sdata;
1108 sdata = container_of(wk, struct ieee80211_sub_if_data,
1109 dec_tailroom_needed_wk.work);
1112 * The reason for the delayed tailroom needed decrementing is to
1113 * make roaming faster: during roaming, all keys are first deleted
1114 * and then new keys are installed. The first new key causes the
1115 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
1116 * the cost of synchronize_net() (which can be slow). Avoid this
1117 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
1118 * key removal for a while, so if we roam the value is larger than
1119 * zero and no 0->1 transition happens.
1121 * The cost is that if the AP switching was from an AP with keys
1122 * to one without, we still allocate tailroom while it would no
1123 * longer be needed. However, in the typical (fast) roaming case
1124 * within an ESS this usually won't happen.
1127 mutex_lock(&sdata->local->key_mtx);
1128 decrease_tailroom_need_count(sdata,
1129 sdata->crypto_tx_tailroom_pending_dec);
1130 sdata->crypto_tx_tailroom_pending_dec = 0;
1131 mutex_unlock(&sdata->local->key_mtx);
1134 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
1135 const u8 *replay_ctr, gfp_t gfp)
1137 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1139 trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
1141 cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
1143 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
1145 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
1146 int tid, struct ieee80211_key_seq *seq)
1148 struct ieee80211_key *key;
1151 key = container_of(keyconf, struct ieee80211_key, conf);
1153 switch (key->conf.cipher) {
1154 case WLAN_CIPHER_SUITE_TKIP:
1155 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1157 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1158 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
1160 case WLAN_CIPHER_SUITE_CCMP:
1161 case WLAN_CIPHER_SUITE_CCMP_256:
1162 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1165 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1167 pn = key->u.ccmp.rx_pn[tid];
1168 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
1170 case WLAN_CIPHER_SUITE_AES_CMAC:
1171 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1172 if (WARN_ON(tid != 0))
1174 pn = key->u.aes_cmac.rx_pn;
1175 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
1177 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1178 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1179 if (WARN_ON(tid != 0))
1181 pn = key->u.aes_gmac.rx_pn;
1182 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
1184 case WLAN_CIPHER_SUITE_GCMP:
1185 case WLAN_CIPHER_SUITE_GCMP_256:
1186 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1189 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1191 pn = key->u.gcmp.rx_pn[tid];
1192 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1196 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1198 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1199 int tid, struct ieee80211_key_seq *seq)
1201 struct ieee80211_key *key;
1204 key = container_of(keyconf, struct ieee80211_key, conf);
1206 switch (key->conf.cipher) {
1207 case WLAN_CIPHER_SUITE_TKIP:
1208 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1210 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1211 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1213 case WLAN_CIPHER_SUITE_CCMP:
1214 case WLAN_CIPHER_SUITE_CCMP_256:
1215 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1218 pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1220 pn = key->u.ccmp.rx_pn[tid];
1221 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1223 case WLAN_CIPHER_SUITE_AES_CMAC:
1224 case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1225 if (WARN_ON(tid != 0))
1227 pn = key->u.aes_cmac.rx_pn;
1228 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1230 case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1231 case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1232 if (WARN_ON(tid != 0))
1234 pn = key->u.aes_gmac.rx_pn;
1235 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1237 case WLAN_CIPHER_SUITE_GCMP:
1238 case WLAN_CIPHER_SUITE_GCMP_256:
1239 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1242 pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1244 pn = key->u.gcmp.rx_pn[tid];
1245 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1252 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1254 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1256 struct ieee80211_key *key;
1258 key = container_of(keyconf, struct ieee80211_key, conf);
1260 assert_key_lock(key->local);
1263 * if key was uploaded, we assume the driver will/has remove(d)
1264 * it, so adjust bookkeeping accordingly
1266 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1267 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1269 if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1270 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
1271 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1272 increment_tailroom_need_count(key->sdata);
1275 ieee80211_key_free(key, false);
1277 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1279 struct ieee80211_key_conf *
1280 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1281 struct ieee80211_key_conf *keyconf)
1283 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1284 struct ieee80211_local *local = sdata->local;
1285 struct ieee80211_key *key;
1288 if (WARN_ON(!local->wowlan))
1289 return ERR_PTR(-EINVAL);
1291 if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1292 return ERR_PTR(-EINVAL);
1294 key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1295 keyconf->keylen, keyconf->key,
1298 return ERR_CAST(key);
1300 if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1301 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1303 err = ieee80211_key_link(key, sdata, NULL);
1305 return ERR_PTR(err);
1309 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);