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TOMOYO Linux Cross Reference
Linux/net/mac80211/key.c

Version: ~ [ linux-5.2-rc4 ] ~ [ linux-5.1.9 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.50 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.125 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.181 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.181 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.68 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
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  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       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 <asm/unaligned.h>
 23 #include "ieee80211_i.h"
 24 #include "driver-ops.h"
 25 #include "debugfs_key.h"
 26 #include "aes_ccm.h"
 27 #include "aes_cmac.h"
 28 #include "aes_gmac.h"
 29 #include "aes_gcm.h"
 30 
 31 
 32 /**
 33  * DOC: Key handling basics
 34  *
 35  * Key handling in mac80211 is done based on per-interface (sub_if_data)
 36  * keys and per-station keys. Since each station belongs to an interface,
 37  * each station key also belongs to that interface.
 38  *
 39  * Hardware acceleration is done on a best-effort basis for algorithms
 40  * that are implemented in software,  for each key the hardware is asked
 41  * to enable that key for offloading but if it cannot do that the key is
 42  * simply kept for software encryption (unless it is for an algorithm
 43  * that isn't implemented in software).
 44  * There is currently no way of knowing whether a key is handled in SW
 45  * or HW except by looking into debugfs.
 46  *
 47  * All key management is internally protected by a mutex. Within all
 48  * other parts of mac80211, key references are, just as STA structure
 49  * references, protected by RCU. Note, however, that some things are
 50  * unprotected, namely the key->sta dereferences within the hardware
 51  * acceleration functions. This means that sta_info_destroy() must
 52  * remove the key which waits for an RCU grace period.
 53  */
 54 
 55 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
 56 
 57 static void assert_key_lock(struct ieee80211_local *local)
 58 {
 59         lockdep_assert_held(&local->key_mtx);
 60 }
 61 
 62 static void
 63 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
 64 {
 65         struct ieee80211_sub_if_data *vlan;
 66 
 67         if (sdata->vif.type != NL80211_IFTYPE_AP)
 68                 return;
 69 
 70         /* crypto_tx_tailroom_needed_cnt is protected by this */
 71         assert_key_lock(sdata->local);
 72 
 73         rcu_read_lock();
 74 
 75         list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
 76                 vlan->crypto_tx_tailroom_needed_cnt += delta;
 77 
 78         rcu_read_unlock();
 79 }
 80 
 81 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
 82 {
 83         /*
 84          * When this count is zero, SKB resizing for allocating tailroom
 85          * for IV or MMIC is skipped. But, this check has created two race
 86          * cases in xmit path while transiting from zero count to one:
 87          *
 88          * 1. SKB resize was skipped because no key was added but just before
 89          * the xmit key is added and SW encryption kicks off.
 90          *
 91          * 2. SKB resize was skipped because all the keys were hw planted but
 92          * just before xmit one of the key is deleted and SW encryption kicks
 93          * off.
 94          *
 95          * In both the above case SW encryption will find not enough space for
 96          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
 97          *
 98          * Solution has been explained at
 99          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
100          */
101 
102         assert_key_lock(sdata->local);
103 
104         update_vlan_tailroom_need_count(sdata, 1);
105 
106         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
107                 /*
108                  * Flush all XMIT packets currently using HW encryption or no
109                  * encryption at all if the count transition is from 0 -> 1.
110                  */
111                 synchronize_net();
112         }
113 }
114 
115 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
116                                          int delta)
117 {
118         assert_key_lock(sdata->local);
119 
120         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
121 
122         update_vlan_tailroom_need_count(sdata, -delta);
123         sdata->crypto_tx_tailroom_needed_cnt -= delta;
124 }
125 
126 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
127 {
128         struct ieee80211_sub_if_data *sdata;
129         struct sta_info *sta;
130         int ret = -EOPNOTSUPP;
131 
132         might_sleep();
133 
134         if (key->flags & KEY_FLAG_TAINTED) {
135                 /* If we get here, it's during resume and the key is
136                  * tainted so shouldn't be used/programmed any more.
137                  * However, its flags may still indicate that it was
138                  * programmed into the device (since we're in resume)
139                  * so clear that flag now to avoid trying to remove
140                  * it again later.
141                  */
142                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
143                 return -EINVAL;
144         }
145 
146         if (!key->local->ops->set_key)
147                 goto out_unsupported;
148 
149         assert_key_lock(key->local);
150 
151         sta = key->sta;
152 
153         /*
154          * If this is a per-STA GTK, check if it
155          * is supported; if not, return.
156          */
157         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
158             !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
159                 goto out_unsupported;
160 
161         if (sta && !sta->uploaded)
162                 goto out_unsupported;
163 
164         sdata = key->sdata;
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                         goto out_unsupported;
172         }
173 
174         ret = drv_set_key(key->local, SET_KEY, sdata,
175                           sta ? &sta->sta : NULL, &key->conf);
176 
177         if (!ret) {
178                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
179 
180                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
181                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
182                         decrease_tailroom_need_count(sdata, 1);
183 
184                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
185                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
186 
187                 return 0;
188         }
189 
190         if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
191                 sdata_err(sdata,
192                           "failed to set key (%d, %pM) to hardware (%d)\n",
193                           key->conf.keyidx,
194                           sta ? sta->sta.addr : bcast_addr, ret);
195 
196  out_unsupported:
197         switch (key->conf.cipher) {
198         case WLAN_CIPHER_SUITE_WEP40:
199         case WLAN_CIPHER_SUITE_WEP104:
200         case WLAN_CIPHER_SUITE_TKIP:
201         case WLAN_CIPHER_SUITE_CCMP:
202         case WLAN_CIPHER_SUITE_CCMP_256:
203         case WLAN_CIPHER_SUITE_AES_CMAC:
204         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
205         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
206         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
207         case WLAN_CIPHER_SUITE_GCMP:
208         case WLAN_CIPHER_SUITE_GCMP_256:
209                 /* all of these we can do in software - if driver can */
210                 if (ret == 1)
211                         return 0;
212                 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
213                         return -EINVAL;
214                 return 0;
215         default:
216                 return -EINVAL;
217         }
218 }
219 
220 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
221 {
222         struct ieee80211_sub_if_data *sdata;
223         struct sta_info *sta;
224         int ret;
225 
226         might_sleep();
227 
228         if (!key || !key->local->ops->set_key)
229                 return;
230 
231         assert_key_lock(key->local);
232 
233         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
234                 return;
235 
236         sta = key->sta;
237         sdata = key->sdata;
238 
239         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
240               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
241                 increment_tailroom_need_count(sdata);
242 
243         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
244                           sta ? &sta->sta : NULL, &key->conf);
245 
246         if (ret)
247                 sdata_err(sdata,
248                           "failed to remove key (%d, %pM) from hardware (%d)\n",
249                           key->conf.keyidx,
250                           sta ? sta->sta.addr : bcast_addr, ret);
251 
252         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
253 }
254 
255 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
256                                         int idx, bool uni, bool multi)
257 {
258         struct ieee80211_key *key = NULL;
259 
260         assert_key_lock(sdata->local);
261 
262         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
263                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
264 
265         if (uni) {
266                 rcu_assign_pointer(sdata->default_unicast_key, key);
267                 ieee80211_check_fast_xmit_iface(sdata);
268                 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
269                         drv_set_default_unicast_key(sdata->local, sdata, idx);
270         }
271 
272         if (multi)
273                 rcu_assign_pointer(sdata->default_multicast_key, key);
274 
275         ieee80211_debugfs_key_update_default(sdata);
276 }
277 
278 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
279                                bool uni, bool multi)
280 {
281         mutex_lock(&sdata->local->key_mtx);
282         __ieee80211_set_default_key(sdata, idx, uni, multi);
283         mutex_unlock(&sdata->local->key_mtx);
284 }
285 
286 static void
287 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
288 {
289         struct ieee80211_key *key = NULL;
290 
291         assert_key_lock(sdata->local);
292 
293         if (idx >= NUM_DEFAULT_KEYS &&
294             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
295                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
296 
297         rcu_assign_pointer(sdata->default_mgmt_key, key);
298 
299         ieee80211_debugfs_key_update_default(sdata);
300 }
301 
302 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
303                                     int idx)
304 {
305         mutex_lock(&sdata->local->key_mtx);
306         __ieee80211_set_default_mgmt_key(sdata, idx);
307         mutex_unlock(&sdata->local->key_mtx);
308 }
309 
310 
311 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
312                                   struct sta_info *sta,
313                                   bool pairwise,
314                                   struct ieee80211_key *old,
315                                   struct ieee80211_key *new)
316 {
317         int idx;
318         bool defunikey, defmultikey, defmgmtkey;
319 
320         /* caller must provide at least one old/new */
321         if (WARN_ON(!new && !old))
322                 return;
323 
324         if (new)
325                 list_add_tail_rcu(&new->list, &sdata->key_list);
326 
327         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
328 
329         if (old)
330                 idx = old->conf.keyidx;
331         else
332                 idx = new->conf.keyidx;
333 
334         if (sta) {
335                 if (pairwise) {
336                         rcu_assign_pointer(sta->ptk[idx], new);
337                         sta->ptk_idx = idx;
338                         ieee80211_check_fast_xmit(sta);
339                 } else {
340                         rcu_assign_pointer(sta->gtk[idx], new);
341                 }
342                 ieee80211_check_fast_rx(sta);
343         } else {
344                 defunikey = old &&
345                         old == key_mtx_dereference(sdata->local,
346                                                 sdata->default_unicast_key);
347                 defmultikey = old &&
348                         old == key_mtx_dereference(sdata->local,
349                                                 sdata->default_multicast_key);
350                 defmgmtkey = old &&
351                         old == key_mtx_dereference(sdata->local,
352                                                 sdata->default_mgmt_key);
353 
354                 if (defunikey && !new)
355                         __ieee80211_set_default_key(sdata, -1, true, false);
356                 if (defmultikey && !new)
357                         __ieee80211_set_default_key(sdata, -1, false, true);
358                 if (defmgmtkey && !new)
359                         __ieee80211_set_default_mgmt_key(sdata, -1);
360 
361                 rcu_assign_pointer(sdata->keys[idx], new);
362                 if (defunikey && new)
363                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
364                                                     true, false);
365                 if (defmultikey && new)
366                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
367                                                     false, true);
368                 if (defmgmtkey && new)
369                         __ieee80211_set_default_mgmt_key(sdata,
370                                                          new->conf.keyidx);
371         }
372 
373         if (old)
374                 list_del_rcu(&old->list);
375 }
376 
377 struct ieee80211_key *
378 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
379                     const u8 *key_data,
380                     size_t seq_len, const u8 *seq,
381                     const struct ieee80211_cipher_scheme *cs)
382 {
383         struct ieee80211_key *key;
384         int i, j, err;
385 
386         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
387                 return ERR_PTR(-EINVAL);
388 
389         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
390         if (!key)
391                 return ERR_PTR(-ENOMEM);
392 
393         /*
394          * Default to software encryption; we'll later upload the
395          * key to the hardware if possible.
396          */
397         key->conf.flags = 0;
398         key->flags = 0;
399 
400         key->conf.cipher = cipher;
401         key->conf.keyidx = idx;
402         key->conf.keylen = key_len;
403         switch (cipher) {
404         case WLAN_CIPHER_SUITE_WEP40:
405         case WLAN_CIPHER_SUITE_WEP104:
406                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
407                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
408                 break;
409         case WLAN_CIPHER_SUITE_TKIP:
410                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
411                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
412                 if (seq) {
413                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
414                                 key->u.tkip.rx[i].iv32 =
415                                         get_unaligned_le32(&seq[2]);
416                                 key->u.tkip.rx[i].iv16 =
417                                         get_unaligned_le16(seq);
418                         }
419                 }
420                 spin_lock_init(&key->u.tkip.txlock);
421                 break;
422         case WLAN_CIPHER_SUITE_CCMP:
423                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
424                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
425                 if (seq) {
426                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
427                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
428                                         key->u.ccmp.rx_pn[i][j] =
429                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
430                 }
431                 /*
432                  * Initialize AES key state here as an optimization so that
433                  * it does not need to be initialized for every packet.
434                  */
435                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
436                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
437                 if (IS_ERR(key->u.ccmp.tfm)) {
438                         err = PTR_ERR(key->u.ccmp.tfm);
439                         kfree(key);
440                         return ERR_PTR(err);
441                 }
442                 break;
443         case WLAN_CIPHER_SUITE_CCMP_256:
444                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
445                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
446                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
447                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
448                                 key->u.ccmp.rx_pn[i][j] =
449                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
450                 /* Initialize AES key state here as an optimization so that
451                  * it does not need to be initialized for every packet.
452                  */
453                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
454                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
455                 if (IS_ERR(key->u.ccmp.tfm)) {
456                         err = PTR_ERR(key->u.ccmp.tfm);
457                         kfree(key);
458                         return ERR_PTR(err);
459                 }
460                 break;
461         case WLAN_CIPHER_SUITE_AES_CMAC:
462         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
463                 key->conf.iv_len = 0;
464                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
465                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
466                 else
467                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
468                 if (seq)
469                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
470                                 key->u.aes_cmac.rx_pn[j] =
471                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
472                 /*
473                  * Initialize AES key state here as an optimization so that
474                  * it does not need to be initialized for every packet.
475                  */
476                 key->u.aes_cmac.tfm =
477                         ieee80211_aes_cmac_key_setup(key_data, key_len);
478                 if (IS_ERR(key->u.aes_cmac.tfm)) {
479                         err = PTR_ERR(key->u.aes_cmac.tfm);
480                         kfree(key);
481                         return ERR_PTR(err);
482                 }
483                 break;
484         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
485         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
486                 key->conf.iv_len = 0;
487                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
488                 if (seq)
489                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
490                                 key->u.aes_gmac.rx_pn[j] =
491                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
492                 /* Initialize AES key state here as an optimization so that
493                  * it does not need to be initialized for every packet.
494                  */
495                 key->u.aes_gmac.tfm =
496                         ieee80211_aes_gmac_key_setup(key_data, key_len);
497                 if (IS_ERR(key->u.aes_gmac.tfm)) {
498                         err = PTR_ERR(key->u.aes_gmac.tfm);
499                         kfree(key);
500                         return ERR_PTR(err);
501                 }
502                 break;
503         case WLAN_CIPHER_SUITE_GCMP:
504         case WLAN_CIPHER_SUITE_GCMP_256:
505                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
506                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
507                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
508                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
509                                 key->u.gcmp.rx_pn[i][j] =
510                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
511                 /* Initialize AES key state here as an optimization so that
512                  * it does not need to be initialized for every packet.
513                  */
514                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
515                                                                       key_len);
516                 if (IS_ERR(key->u.gcmp.tfm)) {
517                         err = PTR_ERR(key->u.gcmp.tfm);
518                         kfree(key);
519                         return ERR_PTR(err);
520                 }
521                 break;
522         default:
523                 if (cs) {
524                         if (seq_len && seq_len != cs->pn_len) {
525                                 kfree(key);
526                                 return ERR_PTR(-EINVAL);
527                         }
528 
529                         key->conf.iv_len = cs->hdr_len;
530                         key->conf.icv_len = cs->mic_len;
531                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
532                                 for (j = 0; j < seq_len; j++)
533                                         key->u.gen.rx_pn[i][j] =
534                                                         seq[seq_len - j - 1];
535                         key->flags |= KEY_FLAG_CIPHER_SCHEME;
536                 }
537         }
538         memcpy(key->conf.key, key_data, key_len);
539         INIT_LIST_HEAD(&key->list);
540 
541         return key;
542 }
543 
544 static void ieee80211_key_free_common(struct ieee80211_key *key)
545 {
546         switch (key->conf.cipher) {
547         case WLAN_CIPHER_SUITE_CCMP:
548         case WLAN_CIPHER_SUITE_CCMP_256:
549                 ieee80211_aes_key_free(key->u.ccmp.tfm);
550                 break;
551         case WLAN_CIPHER_SUITE_AES_CMAC:
552         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
553                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
554                 break;
555         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
556         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
557                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
558                 break;
559         case WLAN_CIPHER_SUITE_GCMP:
560         case WLAN_CIPHER_SUITE_GCMP_256:
561                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
562                 break;
563         }
564         kzfree(key);
565 }
566 
567 static void __ieee80211_key_destroy(struct ieee80211_key *key,
568                                     bool delay_tailroom)
569 {
570         if (key->local)
571                 ieee80211_key_disable_hw_accel(key);
572 
573         if (key->local) {
574                 struct ieee80211_sub_if_data *sdata = key->sdata;
575 
576                 ieee80211_debugfs_key_remove(key);
577 
578                 if (delay_tailroom) {
579                         /* see ieee80211_delayed_tailroom_dec */
580                         sdata->crypto_tx_tailroom_pending_dec++;
581                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
582                                               HZ/2);
583                 } else {
584                         decrease_tailroom_need_count(sdata, 1);
585                 }
586         }
587 
588         ieee80211_key_free_common(key);
589 }
590 
591 static void ieee80211_key_destroy(struct ieee80211_key *key,
592                                   bool delay_tailroom)
593 {
594         if (!key)
595                 return;
596 
597         /*
598          * Synchronize so the TX path and rcu key iterators
599          * can no longer be using this key before we free/remove it.
600          */
601         synchronize_net();
602 
603         __ieee80211_key_destroy(key, delay_tailroom);
604 }
605 
606 void ieee80211_key_free_unused(struct ieee80211_key *key)
607 {
608         WARN_ON(key->sdata || key->local);
609         ieee80211_key_free_common(key);
610 }
611 
612 int ieee80211_key_link(struct ieee80211_key *key,
613                        struct ieee80211_sub_if_data *sdata,
614                        struct sta_info *sta)
615 {
616         struct ieee80211_local *local = sdata->local;
617         struct ieee80211_key *old_key;
618         int idx, ret;
619         bool pairwise;
620 
621         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
622         idx = key->conf.keyidx;
623         key->local = sdata->local;
624         key->sdata = sdata;
625         key->sta = sta;
626 
627         mutex_lock(&sdata->local->key_mtx);
628 
629         if (sta && pairwise)
630                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
631         else if (sta)
632                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
633         else
634                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
635 
636         increment_tailroom_need_count(sdata);
637 
638         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
639         ieee80211_key_destroy(old_key, true);
640 
641         ieee80211_debugfs_key_add(key);
642 
643         if (!local->wowlan) {
644                 ret = ieee80211_key_enable_hw_accel(key);
645                 if (ret)
646                         ieee80211_key_free(key, true);
647         } else {
648                 ret = 0;
649         }
650 
651         mutex_unlock(&sdata->local->key_mtx);
652 
653         return ret;
654 }
655 
656 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
657 {
658         if (!key)
659                 return;
660 
661         /*
662          * Replace key with nothingness if it was ever used.
663          */
664         if (key->sdata)
665                 ieee80211_key_replace(key->sdata, key->sta,
666                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
667                                 key, NULL);
668         ieee80211_key_destroy(key, delay_tailroom);
669 }
670 
671 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
672 {
673         struct ieee80211_key *key;
674         struct ieee80211_sub_if_data *vlan;
675 
676         ASSERT_RTNL();
677 
678         if (WARN_ON(!ieee80211_sdata_running(sdata)))
679                 return;
680 
681         mutex_lock(&sdata->local->key_mtx);
682 
683         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
684                      sdata->crypto_tx_tailroom_pending_dec);
685 
686         if (sdata->vif.type == NL80211_IFTYPE_AP) {
687                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
688                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
689                                      vlan->crypto_tx_tailroom_pending_dec);
690         }
691 
692         list_for_each_entry(key, &sdata->key_list, list) {
693                 increment_tailroom_need_count(sdata);
694                 ieee80211_key_enable_hw_accel(key);
695         }
696 
697         mutex_unlock(&sdata->local->key_mtx);
698 }
699 
700 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
701 {
702         struct ieee80211_sub_if_data *vlan;
703 
704         mutex_lock(&sdata->local->key_mtx);
705 
706         sdata->crypto_tx_tailroom_needed_cnt = 0;
707 
708         if (sdata->vif.type == NL80211_IFTYPE_AP) {
709                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
710                         vlan->crypto_tx_tailroom_needed_cnt = 0;
711         }
712 
713         mutex_unlock(&sdata->local->key_mtx);
714 }
715 
716 void ieee80211_iter_keys(struct ieee80211_hw *hw,
717                          struct ieee80211_vif *vif,
718                          void (*iter)(struct ieee80211_hw *hw,
719                                       struct ieee80211_vif *vif,
720                                       struct ieee80211_sta *sta,
721                                       struct ieee80211_key_conf *key,
722                                       void *data),
723                          void *iter_data)
724 {
725         struct ieee80211_local *local = hw_to_local(hw);
726         struct ieee80211_key *key, *tmp;
727         struct ieee80211_sub_if_data *sdata;
728 
729         ASSERT_RTNL();
730 
731         mutex_lock(&local->key_mtx);
732         if (vif) {
733                 sdata = vif_to_sdata(vif);
734                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
735                         iter(hw, &sdata->vif,
736                              key->sta ? &key->sta->sta : NULL,
737                              &key->conf, iter_data);
738         } else {
739                 list_for_each_entry(sdata, &local->interfaces, list)
740                         list_for_each_entry_safe(key, tmp,
741                                                  &sdata->key_list, list)
742                                 iter(hw, &sdata->vif,
743                                      key->sta ? &key->sta->sta : NULL,
744                                      &key->conf, iter_data);
745         }
746         mutex_unlock(&local->key_mtx);
747 }
748 EXPORT_SYMBOL(ieee80211_iter_keys);
749 
750 static void
751 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
752                          struct ieee80211_sub_if_data *sdata,
753                          void (*iter)(struct ieee80211_hw *hw,
754                                       struct ieee80211_vif *vif,
755                                       struct ieee80211_sta *sta,
756                                       struct ieee80211_key_conf *key,
757                                       void *data),
758                          void *iter_data)
759 {
760         struct ieee80211_key *key;
761 
762         list_for_each_entry_rcu(key, &sdata->key_list, list) {
763                 /* skip keys of station in removal process */
764                 if (key->sta && key->sta->removed)
765                         continue;
766                 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
767                         continue;
768 
769                 iter(hw, &sdata->vif,
770                      key->sta ? &key->sta->sta : NULL,
771                      &key->conf, iter_data);
772         }
773 }
774 
775 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
776                              struct ieee80211_vif *vif,
777                              void (*iter)(struct ieee80211_hw *hw,
778                                           struct ieee80211_vif *vif,
779                                           struct ieee80211_sta *sta,
780                                           struct ieee80211_key_conf *key,
781                                           void *data),
782                              void *iter_data)
783 {
784         struct ieee80211_local *local = hw_to_local(hw);
785         struct ieee80211_sub_if_data *sdata;
786 
787         if (vif) {
788                 sdata = vif_to_sdata(vif);
789                 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
790         } else {
791                 list_for_each_entry_rcu(sdata, &local->interfaces, list)
792                         _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
793         }
794 }
795 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
796 
797 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
798                                       struct list_head *keys)
799 {
800         struct ieee80211_key *key, *tmp;
801 
802         decrease_tailroom_need_count(sdata,
803                                      sdata->crypto_tx_tailroom_pending_dec);
804         sdata->crypto_tx_tailroom_pending_dec = 0;
805 
806         ieee80211_debugfs_key_remove_mgmt_default(sdata);
807 
808         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
809                 ieee80211_key_replace(key->sdata, key->sta,
810                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
811                                 key, NULL);
812                 list_add_tail(&key->list, keys);
813         }
814 
815         ieee80211_debugfs_key_update_default(sdata);
816 }
817 
818 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
819                          bool force_synchronize)
820 {
821         struct ieee80211_local *local = sdata->local;
822         struct ieee80211_sub_if_data *vlan;
823         struct ieee80211_sub_if_data *master;
824         struct ieee80211_key *key, *tmp;
825         LIST_HEAD(keys);
826 
827         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
828 
829         mutex_lock(&local->key_mtx);
830 
831         ieee80211_free_keys_iface(sdata, &keys);
832 
833         if (sdata->vif.type == NL80211_IFTYPE_AP) {
834                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
835                         ieee80211_free_keys_iface(vlan, &keys);
836         }
837 
838         if (!list_empty(&keys) || force_synchronize)
839                 synchronize_net();
840         list_for_each_entry_safe(key, tmp, &keys, list)
841                 __ieee80211_key_destroy(key, false);
842 
843         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
844                 if (sdata->bss) {
845                         master = container_of(sdata->bss,
846                                               struct ieee80211_sub_if_data,
847                                               u.ap);
848 
849                         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
850                                      master->crypto_tx_tailroom_needed_cnt);
851                 }
852         } else {
853                 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
854                              sdata->crypto_tx_tailroom_pending_dec);
855         }
856 
857         if (sdata->vif.type == NL80211_IFTYPE_AP) {
858                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
859                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
860                                      vlan->crypto_tx_tailroom_pending_dec);
861         }
862 
863         mutex_unlock(&local->key_mtx);
864 }
865 
866 void ieee80211_free_sta_keys(struct ieee80211_local *local,
867                              struct sta_info *sta)
868 {
869         struct ieee80211_key *key;
870         int i;
871 
872         mutex_lock(&local->key_mtx);
873         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
874                 key = key_mtx_dereference(local, sta->gtk[i]);
875                 if (!key)
876                         continue;
877                 ieee80211_key_replace(key->sdata, key->sta,
878                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
879                                 key, NULL);
880                 __ieee80211_key_destroy(key, true);
881         }
882 
883         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
884                 key = key_mtx_dereference(local, sta->ptk[i]);
885                 if (!key)
886                         continue;
887                 ieee80211_key_replace(key->sdata, key->sta,
888                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
889                                 key, NULL);
890                 __ieee80211_key_destroy(key, true);
891         }
892 
893         mutex_unlock(&local->key_mtx);
894 }
895 
896 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
897 {
898         struct ieee80211_sub_if_data *sdata;
899 
900         sdata = container_of(wk, struct ieee80211_sub_if_data,
901                              dec_tailroom_needed_wk.work);
902 
903         /*
904          * The reason for the delayed tailroom needed decrementing is to
905          * make roaming faster: during roaming, all keys are first deleted
906          * and then new keys are installed. The first new key causes the
907          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
908          * the cost of synchronize_net() (which can be slow). Avoid this
909          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
910          * key removal for a while, so if we roam the value is larger than
911          * zero and no 0->1 transition happens.
912          *
913          * The cost is that if the AP switching was from an AP with keys
914          * to one without, we still allocate tailroom while it would no
915          * longer be needed. However, in the typical (fast) roaming case
916          * within an ESS this usually won't happen.
917          */
918 
919         mutex_lock(&sdata->local->key_mtx);
920         decrease_tailroom_need_count(sdata,
921                                      sdata->crypto_tx_tailroom_pending_dec);
922         sdata->crypto_tx_tailroom_pending_dec = 0;
923         mutex_unlock(&sdata->local->key_mtx);
924 }
925 
926 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
927                                 const u8 *replay_ctr, gfp_t gfp)
928 {
929         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
930 
931         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
932 
933         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
934 }
935 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
936 
937 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
938                               int tid, struct ieee80211_key_seq *seq)
939 {
940         struct ieee80211_key *key;
941         const u8 *pn;
942 
943         key = container_of(keyconf, struct ieee80211_key, conf);
944 
945         switch (key->conf.cipher) {
946         case WLAN_CIPHER_SUITE_TKIP:
947                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
948                         return;
949                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
950                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
951                 break;
952         case WLAN_CIPHER_SUITE_CCMP:
953         case WLAN_CIPHER_SUITE_CCMP_256:
954                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
955                         return;
956                 if (tid < 0)
957                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
958                 else
959                         pn = key->u.ccmp.rx_pn[tid];
960                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
961                 break;
962         case WLAN_CIPHER_SUITE_AES_CMAC:
963         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
964                 if (WARN_ON(tid != 0))
965                         return;
966                 pn = key->u.aes_cmac.rx_pn;
967                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
968                 break;
969         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
970         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
971                 if (WARN_ON(tid != 0))
972                         return;
973                 pn = key->u.aes_gmac.rx_pn;
974                 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
975                 break;
976         case WLAN_CIPHER_SUITE_GCMP:
977         case WLAN_CIPHER_SUITE_GCMP_256:
978                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
979                         return;
980                 if (tid < 0)
981                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
982                 else
983                         pn = key->u.gcmp.rx_pn[tid];
984                 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
985                 break;
986         }
987 }
988 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
989 
990 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
991                               int tid, struct ieee80211_key_seq *seq)
992 {
993         struct ieee80211_key *key;
994         u8 *pn;
995 
996         key = container_of(keyconf, struct ieee80211_key, conf);
997 
998         switch (key->conf.cipher) {
999         case WLAN_CIPHER_SUITE_TKIP:
1000                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1001                         return;
1002                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1003                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1004                 break;
1005         case WLAN_CIPHER_SUITE_CCMP:
1006         case WLAN_CIPHER_SUITE_CCMP_256:
1007                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1008                         return;
1009                 if (tid < 0)
1010                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1011                 else
1012                         pn = key->u.ccmp.rx_pn[tid];
1013                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1014                 break;
1015         case WLAN_CIPHER_SUITE_AES_CMAC:
1016         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1017                 if (WARN_ON(tid != 0))
1018                         return;
1019                 pn = key->u.aes_cmac.rx_pn;
1020                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1021                 break;
1022         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1023         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1024                 if (WARN_ON(tid != 0))
1025                         return;
1026                 pn = key->u.aes_gmac.rx_pn;
1027                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1028                 break;
1029         case WLAN_CIPHER_SUITE_GCMP:
1030         case WLAN_CIPHER_SUITE_GCMP_256:
1031                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1032                         return;
1033                 if (tid < 0)
1034                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1035                 else
1036                         pn = key->u.gcmp.rx_pn[tid];
1037                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1038                 break;
1039         default:
1040                 WARN_ON(1);
1041                 break;
1042         }
1043 }
1044 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1045 
1046 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1047 {
1048         struct ieee80211_key *key;
1049 
1050         key = container_of(keyconf, struct ieee80211_key, conf);
1051 
1052         assert_key_lock(key->local);
1053 
1054         /*
1055          * if key was uploaded, we assume the driver will/has remove(d)
1056          * it, so adjust bookkeeping accordingly
1057          */
1058         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1059                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1060 
1061                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
1062                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1063                         increment_tailroom_need_count(key->sdata);
1064         }
1065 
1066         ieee80211_key_free(key, false);
1067 }
1068 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1069 
1070 struct ieee80211_key_conf *
1071 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1072                         struct ieee80211_key_conf *keyconf)
1073 {
1074         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1075         struct ieee80211_local *local = sdata->local;
1076         struct ieee80211_key *key;
1077         int err;
1078 
1079         if (WARN_ON(!local->wowlan))
1080                 return ERR_PTR(-EINVAL);
1081 
1082         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1083                 return ERR_PTR(-EINVAL);
1084 
1085         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1086                                   keyconf->keylen, keyconf->key,
1087                                   0, NULL, NULL);
1088         if (IS_ERR(key))
1089                 return ERR_CAST(key);
1090 
1091         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1092                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1093 
1094         err = ieee80211_key_link(key, sdata, NULL);
1095         if (err)
1096                 return ERR_PTR(err);
1097 
1098         return &key->conf;
1099 }
1100 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
1101 

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