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

Version: ~ [ linux-5.5-rc7 ] ~ [ linux-5.4.13 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.97 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.166 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.210 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.210 ] ~ [ 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-3.16.81 ] ~ [ 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-2.6.32.71 ] ~ [ 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                 drv_set_default_unicast_key(sdata->local, sdata, idx);
269         }
270 
271         if (multi)
272                 rcu_assign_pointer(sdata->default_multicast_key, key);
273 
274         ieee80211_debugfs_key_update_default(sdata);
275 }
276 
277 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
278                                bool uni, bool multi)
279 {
280         mutex_lock(&sdata->local->key_mtx);
281         __ieee80211_set_default_key(sdata, idx, uni, multi);
282         mutex_unlock(&sdata->local->key_mtx);
283 }
284 
285 static void
286 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
287 {
288         struct ieee80211_key *key = NULL;
289 
290         assert_key_lock(sdata->local);
291 
292         if (idx >= NUM_DEFAULT_KEYS &&
293             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
294                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
295 
296         rcu_assign_pointer(sdata->default_mgmt_key, key);
297 
298         ieee80211_debugfs_key_update_default(sdata);
299 }
300 
301 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
302                                     int idx)
303 {
304         mutex_lock(&sdata->local->key_mtx);
305         __ieee80211_set_default_mgmt_key(sdata, idx);
306         mutex_unlock(&sdata->local->key_mtx);
307 }
308 
309 
310 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
311                                   struct sta_info *sta,
312                                   bool pairwise,
313                                   struct ieee80211_key *old,
314                                   struct ieee80211_key *new)
315 {
316         int idx;
317         bool defunikey, defmultikey, defmgmtkey;
318 
319         /* caller must provide at least one old/new */
320         if (WARN_ON(!new && !old))
321                 return;
322 
323         if (new)
324                 list_add_tail_rcu(&new->list, &sdata->key_list);
325 
326         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
327 
328         if (old)
329                 idx = old->conf.keyidx;
330         else
331                 idx = new->conf.keyidx;
332 
333         if (sta) {
334                 if (pairwise) {
335                         rcu_assign_pointer(sta->ptk[idx], new);
336                         sta->ptk_idx = idx;
337                         ieee80211_check_fast_xmit(sta);
338                 } else {
339                         rcu_assign_pointer(sta->gtk[idx], new);
340                 }
341         } else {
342                 defunikey = old &&
343                         old == key_mtx_dereference(sdata->local,
344                                                 sdata->default_unicast_key);
345                 defmultikey = old &&
346                         old == key_mtx_dereference(sdata->local,
347                                                 sdata->default_multicast_key);
348                 defmgmtkey = old &&
349                         old == key_mtx_dereference(sdata->local,
350                                                 sdata->default_mgmt_key);
351 
352                 if (defunikey && !new)
353                         __ieee80211_set_default_key(sdata, -1, true, false);
354                 if (defmultikey && !new)
355                         __ieee80211_set_default_key(sdata, -1, false, true);
356                 if (defmgmtkey && !new)
357                         __ieee80211_set_default_mgmt_key(sdata, -1);
358 
359                 rcu_assign_pointer(sdata->keys[idx], new);
360                 if (defunikey && new)
361                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
362                                                     true, false);
363                 if (defmultikey && new)
364                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
365                                                     false, true);
366                 if (defmgmtkey && new)
367                         __ieee80211_set_default_mgmt_key(sdata,
368                                                          new->conf.keyidx);
369         }
370 
371         if (old)
372                 list_del_rcu(&old->list);
373 }
374 
375 struct ieee80211_key *
376 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
377                     const u8 *key_data,
378                     size_t seq_len, const u8 *seq,
379                     const struct ieee80211_cipher_scheme *cs)
380 {
381         struct ieee80211_key *key;
382         int i, j, err;
383 
384         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
385                 return ERR_PTR(-EINVAL);
386 
387         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
388         if (!key)
389                 return ERR_PTR(-ENOMEM);
390 
391         /*
392          * Default to software encryption; we'll later upload the
393          * key to the hardware if possible.
394          */
395         key->conf.flags = 0;
396         key->flags = 0;
397 
398         key->conf.cipher = cipher;
399         key->conf.keyidx = idx;
400         key->conf.keylen = key_len;
401         switch (cipher) {
402         case WLAN_CIPHER_SUITE_WEP40:
403         case WLAN_CIPHER_SUITE_WEP104:
404                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
405                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
406                 break;
407         case WLAN_CIPHER_SUITE_TKIP:
408                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
409                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
410                 if (seq) {
411                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
412                                 key->u.tkip.rx[i].iv32 =
413                                         get_unaligned_le32(&seq[2]);
414                                 key->u.tkip.rx[i].iv16 =
415                                         get_unaligned_le16(seq);
416                         }
417                 }
418                 spin_lock_init(&key->u.tkip.txlock);
419                 break;
420         case WLAN_CIPHER_SUITE_CCMP:
421                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
422                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
423                 if (seq) {
424                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
425                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
426                                         key->u.ccmp.rx_pn[i][j] =
427                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
428                 }
429                 /*
430                  * Initialize AES key state here as an optimization so that
431                  * it does not need to be initialized for every packet.
432                  */
433                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
434                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
435                 if (IS_ERR(key->u.ccmp.tfm)) {
436                         err = PTR_ERR(key->u.ccmp.tfm);
437                         kfree(key);
438                         return ERR_PTR(err);
439                 }
440                 break;
441         case WLAN_CIPHER_SUITE_CCMP_256:
442                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
443                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
444                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
445                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
446                                 key->u.ccmp.rx_pn[i][j] =
447                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
448                 /* Initialize AES key state here as an optimization so that
449                  * it does not need to be initialized for every packet.
450                  */
451                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
452                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
453                 if (IS_ERR(key->u.ccmp.tfm)) {
454                         err = PTR_ERR(key->u.ccmp.tfm);
455                         kfree(key);
456                         return ERR_PTR(err);
457                 }
458                 break;
459         case WLAN_CIPHER_SUITE_AES_CMAC:
460         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
461                 key->conf.iv_len = 0;
462                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
463                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
464                 else
465                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
466                 if (seq)
467                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
468                                 key->u.aes_cmac.rx_pn[j] =
469                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
470                 /*
471                  * Initialize AES key state here as an optimization so that
472                  * it does not need to be initialized for every packet.
473                  */
474                 key->u.aes_cmac.tfm =
475                         ieee80211_aes_cmac_key_setup(key_data, key_len);
476                 if (IS_ERR(key->u.aes_cmac.tfm)) {
477                         err = PTR_ERR(key->u.aes_cmac.tfm);
478                         kfree(key);
479                         return ERR_PTR(err);
480                 }
481                 break;
482         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
483         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
484                 key->conf.iv_len = 0;
485                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
486                 if (seq)
487                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
488                                 key->u.aes_gmac.rx_pn[j] =
489                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
490                 /* Initialize AES key state here as an optimization so that
491                  * it does not need to be initialized for every packet.
492                  */
493                 key->u.aes_gmac.tfm =
494                         ieee80211_aes_gmac_key_setup(key_data, key_len);
495                 if (IS_ERR(key->u.aes_gmac.tfm)) {
496                         err = PTR_ERR(key->u.aes_gmac.tfm);
497                         kfree(key);
498                         return ERR_PTR(err);
499                 }
500                 break;
501         case WLAN_CIPHER_SUITE_GCMP:
502         case WLAN_CIPHER_SUITE_GCMP_256:
503                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
504                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
505                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
506                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
507                                 key->u.gcmp.rx_pn[i][j] =
508                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
509                 /* Initialize AES key state here as an optimization so that
510                  * it does not need to be initialized for every packet.
511                  */
512                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
513                                                                       key_len);
514                 if (IS_ERR(key->u.gcmp.tfm)) {
515                         err = PTR_ERR(key->u.gcmp.tfm);
516                         kfree(key);
517                         return ERR_PTR(err);
518                 }
519                 break;
520         default:
521                 if (cs) {
522                         if (seq_len && seq_len != cs->pn_len) {
523                                 kfree(key);
524                                 return ERR_PTR(-EINVAL);
525                         }
526 
527                         key->conf.iv_len = cs->hdr_len;
528                         key->conf.icv_len = cs->mic_len;
529                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
530                                 for (j = 0; j < seq_len; j++)
531                                         key->u.gen.rx_pn[i][j] =
532                                                         seq[seq_len - j - 1];
533                         key->flags |= KEY_FLAG_CIPHER_SCHEME;
534                 }
535         }
536         memcpy(key->conf.key, key_data, key_len);
537         INIT_LIST_HEAD(&key->list);
538 
539         return key;
540 }
541 
542 static void ieee80211_key_free_common(struct ieee80211_key *key)
543 {
544         switch (key->conf.cipher) {
545         case WLAN_CIPHER_SUITE_CCMP:
546         case WLAN_CIPHER_SUITE_CCMP_256:
547                 ieee80211_aes_key_free(key->u.ccmp.tfm);
548                 break;
549         case WLAN_CIPHER_SUITE_AES_CMAC:
550         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
551                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
552                 break;
553         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
554         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
555                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
556                 break;
557         case WLAN_CIPHER_SUITE_GCMP:
558         case WLAN_CIPHER_SUITE_GCMP_256:
559                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
560                 break;
561         }
562         kzfree(key);
563 }
564 
565 static void __ieee80211_key_destroy(struct ieee80211_key *key,
566                                     bool delay_tailroom)
567 {
568         if (key->local)
569                 ieee80211_key_disable_hw_accel(key);
570 
571         if (key->local) {
572                 struct ieee80211_sub_if_data *sdata = key->sdata;
573 
574                 ieee80211_debugfs_key_remove(key);
575 
576                 if (delay_tailroom) {
577                         /* see ieee80211_delayed_tailroom_dec */
578                         sdata->crypto_tx_tailroom_pending_dec++;
579                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
580                                               HZ/2);
581                 } else {
582                         decrease_tailroom_need_count(sdata, 1);
583                 }
584         }
585 
586         ieee80211_key_free_common(key);
587 }
588 
589 static void ieee80211_key_destroy(struct ieee80211_key *key,
590                                   bool delay_tailroom)
591 {
592         if (!key)
593                 return;
594 
595         /*
596          * Synchronize so the TX path and rcu key iterators
597          * can no longer be using this key before we free/remove it.
598          */
599         synchronize_net();
600 
601         __ieee80211_key_destroy(key, delay_tailroom);
602 }
603 
604 void ieee80211_key_free_unused(struct ieee80211_key *key)
605 {
606         WARN_ON(key->sdata || key->local);
607         ieee80211_key_free_common(key);
608 }
609 
610 int ieee80211_key_link(struct ieee80211_key *key,
611                        struct ieee80211_sub_if_data *sdata,
612                        struct sta_info *sta)
613 {
614         struct ieee80211_local *local = sdata->local;
615         struct ieee80211_key *old_key;
616         int idx, ret;
617         bool pairwise;
618 
619         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
620         idx = key->conf.keyidx;
621         key->local = sdata->local;
622         key->sdata = sdata;
623         key->sta = sta;
624 
625         mutex_lock(&sdata->local->key_mtx);
626 
627         if (sta && pairwise)
628                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
629         else if (sta)
630                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
631         else
632                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
633 
634         increment_tailroom_need_count(sdata);
635 
636         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
637         ieee80211_key_destroy(old_key, true);
638 
639         ieee80211_debugfs_key_add(key);
640 
641         if (!local->wowlan) {
642                 ret = ieee80211_key_enable_hw_accel(key);
643                 if (ret)
644                         ieee80211_key_free(key, true);
645         } else {
646                 ret = 0;
647         }
648 
649         mutex_unlock(&sdata->local->key_mtx);
650 
651         return ret;
652 }
653 
654 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
655 {
656         if (!key)
657                 return;
658 
659         /*
660          * Replace key with nothingness if it was ever used.
661          */
662         if (key->sdata)
663                 ieee80211_key_replace(key->sdata, key->sta,
664                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
665                                 key, NULL);
666         ieee80211_key_destroy(key, delay_tailroom);
667 }
668 
669 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
670 {
671         struct ieee80211_key *key;
672         struct ieee80211_sub_if_data *vlan;
673 
674         ASSERT_RTNL();
675 
676         if (WARN_ON(!ieee80211_sdata_running(sdata)))
677                 return;
678 
679         mutex_lock(&sdata->local->key_mtx);
680 
681         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
682                      sdata->crypto_tx_tailroom_pending_dec);
683 
684         if (sdata->vif.type == NL80211_IFTYPE_AP) {
685                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
686                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
687                                      vlan->crypto_tx_tailroom_pending_dec);
688         }
689 
690         list_for_each_entry(key, &sdata->key_list, list) {
691                 increment_tailroom_need_count(sdata);
692                 ieee80211_key_enable_hw_accel(key);
693         }
694 
695         mutex_unlock(&sdata->local->key_mtx);
696 }
697 
698 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
699 {
700         struct ieee80211_sub_if_data *vlan;
701 
702         mutex_lock(&sdata->local->key_mtx);
703 
704         sdata->crypto_tx_tailroom_needed_cnt = 0;
705 
706         if (sdata->vif.type == NL80211_IFTYPE_AP) {
707                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
708                         vlan->crypto_tx_tailroom_needed_cnt = 0;
709         }
710 
711         mutex_unlock(&sdata->local->key_mtx);
712 }
713 
714 void ieee80211_iter_keys(struct ieee80211_hw *hw,
715                          struct ieee80211_vif *vif,
716                          void (*iter)(struct ieee80211_hw *hw,
717                                       struct ieee80211_vif *vif,
718                                       struct ieee80211_sta *sta,
719                                       struct ieee80211_key_conf *key,
720                                       void *data),
721                          void *iter_data)
722 {
723         struct ieee80211_local *local = hw_to_local(hw);
724         struct ieee80211_key *key, *tmp;
725         struct ieee80211_sub_if_data *sdata;
726 
727         ASSERT_RTNL();
728 
729         mutex_lock(&local->key_mtx);
730         if (vif) {
731                 sdata = vif_to_sdata(vif);
732                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
733                         iter(hw, &sdata->vif,
734                              key->sta ? &key->sta->sta : NULL,
735                              &key->conf, iter_data);
736         } else {
737                 list_for_each_entry(sdata, &local->interfaces, list)
738                         list_for_each_entry_safe(key, tmp,
739                                                  &sdata->key_list, list)
740                                 iter(hw, &sdata->vif,
741                                      key->sta ? &key->sta->sta : NULL,
742                                      &key->conf, iter_data);
743         }
744         mutex_unlock(&local->key_mtx);
745 }
746 EXPORT_SYMBOL(ieee80211_iter_keys);
747 
748 static void
749 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
750                          struct ieee80211_sub_if_data *sdata,
751                          void (*iter)(struct ieee80211_hw *hw,
752                                       struct ieee80211_vif *vif,
753                                       struct ieee80211_sta *sta,
754                                       struct ieee80211_key_conf *key,
755                                       void *data),
756                          void *iter_data)
757 {
758         struct ieee80211_key *key;
759 
760         list_for_each_entry_rcu(key, &sdata->key_list, list) {
761                 /* skip keys of station in removal process */
762                 if (key->sta && key->sta->removed)
763                         continue;
764                 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
765                         continue;
766 
767                 iter(hw, &sdata->vif,
768                      key->sta ? &key->sta->sta : NULL,
769                      &key->conf, iter_data);
770         }
771 }
772 
773 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
774                              struct ieee80211_vif *vif,
775                              void (*iter)(struct ieee80211_hw *hw,
776                                           struct ieee80211_vif *vif,
777                                           struct ieee80211_sta *sta,
778                                           struct ieee80211_key_conf *key,
779                                           void *data),
780                              void *iter_data)
781 {
782         struct ieee80211_local *local = hw_to_local(hw);
783         struct ieee80211_sub_if_data *sdata;
784 
785         if (vif) {
786                 sdata = vif_to_sdata(vif);
787                 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
788         } else {
789                 list_for_each_entry_rcu(sdata, &local->interfaces, list)
790                         _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
791         }
792 }
793 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
794 
795 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
796                                       struct list_head *keys)
797 {
798         struct ieee80211_key *key, *tmp;
799 
800         decrease_tailroom_need_count(sdata,
801                                      sdata->crypto_tx_tailroom_pending_dec);
802         sdata->crypto_tx_tailroom_pending_dec = 0;
803 
804         ieee80211_debugfs_key_remove_mgmt_default(sdata);
805 
806         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
807                 ieee80211_key_replace(key->sdata, key->sta,
808                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
809                                 key, NULL);
810                 list_add_tail(&key->list, keys);
811         }
812 
813         ieee80211_debugfs_key_update_default(sdata);
814 }
815 
816 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
817                          bool force_synchronize)
818 {
819         struct ieee80211_local *local = sdata->local;
820         struct ieee80211_sub_if_data *vlan;
821         struct ieee80211_sub_if_data *master;
822         struct ieee80211_key *key, *tmp;
823         LIST_HEAD(keys);
824 
825         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
826 
827         mutex_lock(&local->key_mtx);
828 
829         ieee80211_free_keys_iface(sdata, &keys);
830 
831         if (sdata->vif.type == NL80211_IFTYPE_AP) {
832                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
833                         ieee80211_free_keys_iface(vlan, &keys);
834         }
835 
836         if (!list_empty(&keys) || force_synchronize)
837                 synchronize_net();
838         list_for_each_entry_safe(key, tmp, &keys, list)
839                 __ieee80211_key_destroy(key, false);
840 
841         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
842                 if (sdata->bss) {
843                         master = container_of(sdata->bss,
844                                               struct ieee80211_sub_if_data,
845                                               u.ap);
846 
847                         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
848                                      master->crypto_tx_tailroom_needed_cnt);
849                 }
850         } else {
851                 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
852                              sdata->crypto_tx_tailroom_pending_dec);
853         }
854 
855         if (sdata->vif.type == NL80211_IFTYPE_AP) {
856                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
857                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
858                                      vlan->crypto_tx_tailroom_pending_dec);
859         }
860 
861         mutex_unlock(&local->key_mtx);
862 }
863 
864 void ieee80211_free_sta_keys(struct ieee80211_local *local,
865                              struct sta_info *sta)
866 {
867         struct ieee80211_key *key;
868         int i;
869 
870         mutex_lock(&local->key_mtx);
871         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
872                 key = key_mtx_dereference(local, sta->gtk[i]);
873                 if (!key)
874                         continue;
875                 ieee80211_key_replace(key->sdata, key->sta,
876                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
877                                 key, NULL);
878                 __ieee80211_key_destroy(key, true);
879         }
880 
881         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
882                 key = key_mtx_dereference(local, sta->ptk[i]);
883                 if (!key)
884                         continue;
885                 ieee80211_key_replace(key->sdata, key->sta,
886                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
887                                 key, NULL);
888                 __ieee80211_key_destroy(key, true);
889         }
890 
891         mutex_unlock(&local->key_mtx);
892 }
893 
894 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
895 {
896         struct ieee80211_sub_if_data *sdata;
897 
898         sdata = container_of(wk, struct ieee80211_sub_if_data,
899                              dec_tailroom_needed_wk.work);
900 
901         /*
902          * The reason for the delayed tailroom needed decrementing is to
903          * make roaming faster: during roaming, all keys are first deleted
904          * and then new keys are installed. The first new key causes the
905          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
906          * the cost of synchronize_net() (which can be slow). Avoid this
907          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
908          * key removal for a while, so if we roam the value is larger than
909          * zero and no 0->1 transition happens.
910          *
911          * The cost is that if the AP switching was from an AP with keys
912          * to one without, we still allocate tailroom while it would no
913          * longer be needed. However, in the typical (fast) roaming case
914          * within an ESS this usually won't happen.
915          */
916 
917         mutex_lock(&sdata->local->key_mtx);
918         decrease_tailroom_need_count(sdata,
919                                      sdata->crypto_tx_tailroom_pending_dec);
920         sdata->crypto_tx_tailroom_pending_dec = 0;
921         mutex_unlock(&sdata->local->key_mtx);
922 }
923 
924 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
925                                 const u8 *replay_ctr, gfp_t gfp)
926 {
927         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
928 
929         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
930 
931         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
932 }
933 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
934 
935 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
936                               int tid, struct ieee80211_key_seq *seq)
937 {
938         struct ieee80211_key *key;
939         const u8 *pn;
940 
941         key = container_of(keyconf, struct ieee80211_key, conf);
942 
943         switch (key->conf.cipher) {
944         case WLAN_CIPHER_SUITE_TKIP:
945                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
946                         return;
947                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
948                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
949                 break;
950         case WLAN_CIPHER_SUITE_CCMP:
951         case WLAN_CIPHER_SUITE_CCMP_256:
952                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
953                         return;
954                 if (tid < 0)
955                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
956                 else
957                         pn = key->u.ccmp.rx_pn[tid];
958                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
959                 break;
960         case WLAN_CIPHER_SUITE_AES_CMAC:
961         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
962                 if (WARN_ON(tid != 0))
963                         return;
964                 pn = key->u.aes_cmac.rx_pn;
965                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
966                 break;
967         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
968         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
969                 if (WARN_ON(tid != 0))
970                         return;
971                 pn = key->u.aes_gmac.rx_pn;
972                 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
973                 break;
974         case WLAN_CIPHER_SUITE_GCMP:
975         case WLAN_CIPHER_SUITE_GCMP_256:
976                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
977                         return;
978                 if (tid < 0)
979                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
980                 else
981                         pn = key->u.gcmp.rx_pn[tid];
982                 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
983                 break;
984         }
985 }
986 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
987 
988 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
989                               int tid, struct ieee80211_key_seq *seq)
990 {
991         struct ieee80211_key *key;
992         u8 *pn;
993 
994         key = container_of(keyconf, struct ieee80211_key, conf);
995 
996         switch (key->conf.cipher) {
997         case WLAN_CIPHER_SUITE_TKIP:
998                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
999                         return;
1000                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1001                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1002                 break;
1003         case WLAN_CIPHER_SUITE_CCMP:
1004         case WLAN_CIPHER_SUITE_CCMP_256:
1005                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1006                         return;
1007                 if (tid < 0)
1008                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1009                 else
1010                         pn = key->u.ccmp.rx_pn[tid];
1011                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1012                 break;
1013         case WLAN_CIPHER_SUITE_AES_CMAC:
1014         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1015                 if (WARN_ON(tid != 0))
1016                         return;
1017                 pn = key->u.aes_cmac.rx_pn;
1018                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1019                 break;
1020         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1021         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1022                 if (WARN_ON(tid != 0))
1023                         return;
1024                 pn = key->u.aes_gmac.rx_pn;
1025                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1026                 break;
1027         case WLAN_CIPHER_SUITE_GCMP:
1028         case WLAN_CIPHER_SUITE_GCMP_256:
1029                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1030                         return;
1031                 if (tid < 0)
1032                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1033                 else
1034                         pn = key->u.gcmp.rx_pn[tid];
1035                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1036                 break;
1037         default:
1038                 WARN_ON(1);
1039                 break;
1040         }
1041 }
1042 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1043 
1044 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1045 {
1046         struct ieee80211_key *key;
1047 
1048         key = container_of(keyconf, struct ieee80211_key, conf);
1049 
1050         assert_key_lock(key->local);
1051 
1052         /*
1053          * if key was uploaded, we assume the driver will/has remove(d)
1054          * it, so adjust bookkeeping accordingly
1055          */
1056         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1057                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1058 
1059                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
1060                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1061                         increment_tailroom_need_count(key->sdata);
1062         }
1063 
1064         ieee80211_key_free(key, false);
1065 }
1066 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1067 
1068 struct ieee80211_key_conf *
1069 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1070                         struct ieee80211_key_conf *keyconf)
1071 {
1072         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1073         struct ieee80211_local *local = sdata->local;
1074         struct ieee80211_key *key;
1075         int err;
1076 
1077         if (WARN_ON(!local->wowlan))
1078                 return ERR_PTR(-EINVAL);
1079 
1080         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1081                 return ERR_PTR(-EINVAL);
1082 
1083         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1084                                   keyconf->keylen, keyconf->key,
1085                                   0, NULL, NULL);
1086         if (IS_ERR(key))
1087                 return ERR_CAST(key);
1088 
1089         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1090                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1091 
1092         err = ieee80211_key_link(key, sdata, NULL);
1093         if (err)
1094                 return ERR_PTR(err);
1095 
1096         return &key->conf;
1097 }
1098 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
1099 

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