net/mac80211/key.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2008  Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  * Copyright 2015-2017  Intel Deutschland GmbH
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/if_ether.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/list.h>
  17 #include <linux/rcupdate.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/slab.h>
  20 #include <linux/export.h>
  21 #include <net/mac80211.h>
  22 #include <crypto/algapi.h>
  23 #include <asm/unaligned.h>
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "debugfs_key.h"
  27 #include "aes_ccm.h"
  28 #include "aes_cmac.h"
  29 #include "aes_gmac.h"
  30 #include "aes_gcm.h"
  31
  32
  33 /**
  34  * DOC: Key handling basics
  35  *
  36  * Key handling in mac80211 is done based on per-interface (sub_if_data)
  37  * keys and per-station keys. Since each station belongs to an interface,
  38  * each station key also belongs to that interface.
  39  *
  40  * Hardware acceleration is done on a best-effort basis for algorithms
  41  * that are implemented in software,  for each key the hardware is asked
  42  * to enable that key for offloading but if it cannot do that the key is
  43  * simply kept for software encryption (unless it is for an algorithm
  44  * that isn't implemented in software).
  45  * There is currently no way of knowing whether a key is handled in SW
  46  * or HW except by looking into debugfs.
  47  *
  48  * All key management is internally protected by a mutex. Within all
  49  * other parts of mac80211, key references are, just as STA structure
  50  * references, protected by RCU. Note, however, that some things are
  51  * unprotected, namely the key->sta dereferences within the hardware
  52  * acceleration functions. This means that sta_info_destroy() must
  53  * remove the key which waits for an RCU grace period.
  54  */
  55
  56 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  57
  58 static void assert_key_lock(struct ieee80211_local *local)
  59 {
  60         lockdep_assert_held(&local->key_mtx);
  61 }
  62
  63 static void
  64 update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
  65 {
  66         struct ieee80211_sub_if_data *vlan;
  67
  68         if (sdata->vif.type != NL80211_IFTYPE_AP)
  69                 return;
  70
  71         /* crypto_tx_tailroom_needed_cnt is protected by this */
  72         assert_key_lock(sdata->local);
  73
  74         rcu_read_lock();
  75
  76         list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
  77                 vlan->crypto_tx_tailroom_needed_cnt += delta;
  78
  79         rcu_read_unlock();
  80 }
  81
  82 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  83 {
  84         /*
  85          * When this count is zero, SKB resizing for allocating tailroom
  86          * for IV or MMIC is skipped. But, this check has created two race
  87          * cases in xmit path while transiting from zero count to one:
  88          *
  89          * 1. SKB resize was skipped because no key was added but just before
  90          * the xmit key is added and SW encryption kicks off.
  91          *
  92          * 2. SKB resize was skipped because all the keys were hw planted but
  93          * just before xmit one of the key is deleted and SW encryption kicks
  94          * off.
  95          *
  96          * In both the above case SW encryption will find not enough space for
  97          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  98          *
  99          * Solution has been explained at
 100          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
 101          */
 102
 103         assert_key_lock(sdata->local);
 104
 105         update_vlan_tailroom_need_count(sdata, 1);
 106
 107         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
 108                 /*
 109                  * Flush all XMIT packets currently using HW encryption or no
 110                  * encryption at all if the count transition is from 0 -> 1.
 111                  */
 112                 synchronize_net();
 113         }
 114 }
 115
 116 static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
 117                                          int delta)
 118 {
 119         assert_key_lock(sdata->local);
 120
 121         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
 122
 123         update_vlan_tailroom_need_count(sdata, -delta);
 124         sdata->crypto_tx_tailroom_needed_cnt -= delta;
 125 }
 126
 127 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
 128 {
 129         struct ieee80211_sub_if_data *sdata = key->sdata;
 130         struct sta_info *sta;
 131         int ret = -EOPNOTSUPP;
 132
 133         might_sleep();
 134
 135         if (key->flags & KEY_FLAG_TAINTED) {
 136                 /* If we get here, it's during resume and the key is
 137                  * tainted so shouldn't be used/programmed any more.
 138                  * However, its flags may still indicate that it was
 139                  * programmed into the device (since we're in resume)
 140                  * so clear that flag now to avoid trying to remove
 141                  * it again later.
 142                  */
 143                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 144                 return -EINVAL;
 145         }
 146
 147         if (!key->local->ops->set_key)
 148                 goto out_unsupported;
 149
 150         assert_key_lock(key->local);
 151
 152         sta = key->sta;
 153
 154         /*
 155          * If this is a per-STA GTK, check if it
 156          * is supported; if not, return.
 157          */
 158         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
 159             !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
 160                 goto out_unsupported;
 161
 162         if (sta && !sta->uploaded)
 163                 goto out_unsupported;
 164
 165         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 166                 /*
 167                  * The driver doesn't know anything about VLAN interfaces.
 168                  * Hence, don't send GTKs for VLAN interfaces to the driver.
 169                  */
 170                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
 171                         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                                            IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
 182                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 183                         decrease_tailroom_need_count(sdata, 1);
 184
 185                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 186                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 187
 188                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
 189                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
 190
 191                 return 0;
 192         }
 193
 194         if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
 195                 sdata_err(sdata,
 196                           "failed to set key (%d, %pM) to hardware (%d)\n",
 197                           key->conf.keyidx,
 198                           sta ? sta->sta.addr : bcast_addr, ret);
 199
 200  out_unsupported:
 201         switch (key->conf.cipher) {
 202         case WLAN_CIPHER_SUITE_WEP40:
 203         case WLAN_CIPHER_SUITE_WEP104:
 204         case WLAN_CIPHER_SUITE_TKIP:
 205         case WLAN_CIPHER_SUITE_CCMP:
 206         case WLAN_CIPHER_SUITE_CCMP_256:
 207         case WLAN_CIPHER_SUITE_AES_CMAC:
 208         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 209         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 210         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 211         case WLAN_CIPHER_SUITE_GCMP:
 212         case WLAN_CIPHER_SUITE_GCMP_256:
 213                 /* all of these we can do in software - if driver can */
 214                 if (ret == 1)
 215                         return 0;
 216                 if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL)) {
 217                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 218                                 return 0;
 219                         return -EINVAL;
 220                 }
 221                 return 0;
 222         default:
 223                 return -EINVAL;
 224         }
 225 }
 226
 227 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 228 {
 229         struct ieee80211_sub_if_data *sdata;
 230         struct sta_info *sta;
 231         int ret;
 232
 233         might_sleep();
 234
 235         if (!key || !key->local->ops->set_key)
 236                 return;
 237
 238         assert_key_lock(key->local);
 239
 240         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 241                 return;
 242
 243         sta = key->sta;
 244         sdata = key->sdata;
 245
 246         if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
 247                                    IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
 248               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 249                 increment_tailroom_need_count(sdata);
 250
 251         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 252                           sta ? &sta->sta : NULL, &key->conf);
 253
 254         if (ret)
 255                 sdata_err(sdata,
 256                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 257                           key->conf.keyidx,
 258                           sta ? sta->sta.addr : bcast_addr, ret);
 259
 260         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 261 }
 262
 263 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 264                                         int idx, bool uni, bool multi)
 265 {
 266         struct ieee80211_key *key = NULL;
 267
 268         assert_key_lock(sdata->local);
 269
 270         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 271                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 272
 273         if (uni) {
 274                 rcu_assign_pointer(sdata->default_unicast_key, key);
 275                 ieee80211_check_fast_xmit_iface(sdata);
 276                 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
 277                         drv_set_default_unicast_key(sdata->local, sdata, idx);
 278         }
 279
 280         if (multi)
 281                 rcu_assign_pointer(sdata->default_multicast_key, key);
 282
 283         ieee80211_debugfs_key_update_default(sdata);
 284 }
 285
 286 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 287                                bool uni, bool multi)
 288 {
 289         mutex_lock(&sdata->local->key_mtx);
 290         __ieee80211_set_default_key(sdata, idx, uni, multi);
 291         mutex_unlock(&sdata->local->key_mtx);
 292 }
 293
 294 static void
 295 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 296 {
 297         struct ieee80211_key *key = NULL;
 298
 299         assert_key_lock(sdata->local);
 300
 301         if (idx >= NUM_DEFAULT_KEYS &&
 302             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 303                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 304
 305         rcu_assign_pointer(sdata->default_mgmt_key, key);
 306
 307         ieee80211_debugfs_key_update_default(sdata);
 308 }
 309
 310 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 311                                     int idx)
 312 {
 313         mutex_lock(&sdata->local->key_mtx);
 314         __ieee80211_set_default_mgmt_key(sdata, idx);
 315         mutex_unlock(&sdata->local->key_mtx);
 316 }
 317
 318
 319 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 320                                   struct sta_info *sta,
 321                                   bool pairwise,
 322                                   struct ieee80211_key *old,
 323                                   struct ieee80211_key *new)
 324 {
 325         int idx;
 326         bool defunikey, defmultikey, defmgmtkey;
 327
 328         /* caller must provide at least one old/new */
 329         if (WARN_ON(!new && !old))
 330                 return;
 331
 332         if (new)
 333                 list_add_tail_rcu(&new->list, &sdata->key_list);
 334
 335         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 336
 337         if (old)
 338                 idx = old->conf.keyidx;
 339         else
 340                 idx = new->conf.keyidx;
 341
 342         if (sta) {
 343                 if (pairwise) {
 344                         rcu_assign_pointer(sta->ptk[idx], new);
 345                         sta->ptk_idx = idx;
 346                         ieee80211_check_fast_xmit(sta);
 347                 } else {
 348                         rcu_assign_pointer(sta->gtk[idx], new);
 349                 }
 350                 ieee80211_check_fast_rx(sta);
 351         } else {
 352                 defunikey = old &&
 353                         old == key_mtx_dereference(sdata->local,
 354                                                 sdata->default_unicast_key);
 355                 defmultikey = old &&
 356                         old == key_mtx_dereference(sdata->local,
 357                                                 sdata->default_multicast_key);
 358                 defmgmtkey = old &&
 359                         old == key_mtx_dereference(sdata->local,
 360                                                 sdata->default_mgmt_key);
 361
 362                 if (defunikey && !new)
 363                         __ieee80211_set_default_key(sdata, -1, true, false);
 364                 if (defmultikey && !new)
 365                         __ieee80211_set_default_key(sdata, -1, false, true);
 366                 if (defmgmtkey && !new)
 367                         __ieee80211_set_default_mgmt_key(sdata, -1);
 368
 369                 rcu_assign_pointer(sdata->keys[idx], new);
 370                 if (defunikey && new)
 371                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 372                                                     true, false);
 373                 if (defmultikey && new)
 374                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 375                                                     false, true);
 376                 if (defmgmtkey && new)
 377                         __ieee80211_set_default_mgmt_key(sdata,
 378                                                          new->conf.keyidx);
 379         }
 380
 381         if (old)
 382                 list_del_rcu(&old->list);
 383 }
 384
 385 struct ieee80211_key *
 386 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 387                     const u8 *key_data,
 388                     size_t seq_len, const u8 *seq,
 389                     const struct ieee80211_cipher_scheme *cs)
 390 {
 391         struct ieee80211_key *key;
 392         int i, j, err;
 393
 394         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 395                 return ERR_PTR(-EINVAL);
 396
 397         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 398         if (!key)
 399                 return ERR_PTR(-ENOMEM);
 400
 401         /*
 402          * Default to software encryption; we'll later upload the
 403          * key to the hardware if possible.
 404          */
 405         key->conf.flags = 0;
 406         key->flags = 0;
 407
 408         key->conf.cipher = cipher;
 409         key->conf.keyidx = idx;
 410         key->conf.keylen = key_len;
 411         switch (cipher) {
 412         case WLAN_CIPHER_SUITE_WEP40:
 413         case WLAN_CIPHER_SUITE_WEP104:
 414                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 415                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 416                 break;
 417         case WLAN_CIPHER_SUITE_TKIP:
 418                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 419                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 420                 if (seq) {
 421                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 422                                 key->u.tkip.rx[i].iv32 =
 423                                         get_unaligned_le32(&seq[2]);
 424                                 key->u.tkip.rx[i].iv16 =
 425                                         get_unaligned_le16(seq);
 426                         }
 427                 }
 428                 spin_lock_init(&key->u.tkip.txlock);
 429                 break;
 430         case WLAN_CIPHER_SUITE_CCMP:
 431                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 432                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 433                 if (seq) {
 434                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 435                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 436                                         key->u.ccmp.rx_pn[i][j] =
 437                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 438                 }
 439                 /*
 440                  * Initialize AES key state here as an optimization so that
 441                  * it does not need to be initialized for every packet.
 442                  */
 443                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 444                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
 445                 if (IS_ERR(key->u.ccmp.tfm)) {
 446                         err = PTR_ERR(key->u.ccmp.tfm);
 447                         kfree(key);
 448                         return ERR_PTR(err);
 449                 }
 450                 break;
 451         case WLAN_CIPHER_SUITE_CCMP_256:
 452                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
 453                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
 454                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 455                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
 456                                 key->u.ccmp.rx_pn[i][j] =
 457                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
 458                 /* Initialize AES key state here as an optimization so that
 459                  * it does not need to be initialized for every packet.
 460                  */
 461                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 462                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
 463                 if (IS_ERR(key->u.ccmp.tfm)) {
 464                         err = PTR_ERR(key->u.ccmp.tfm);
 465                         kfree(key);
 466                         return ERR_PTR(err);
 467                 }
 468                 break;
 469         case WLAN_CIPHER_SUITE_AES_CMAC:
 470         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 471                 key->conf.iv_len = 0;
 472                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 473                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
 474                 else
 475                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 476                 if (seq)
 477                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 478                                 key->u.aes_cmac.rx_pn[j] =
 479                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 480                 /*
 481                  * Initialize AES key state here as an optimization so that
 482                  * it does not need to be initialized for every packet.
 483                  */
 484                 key->u.aes_cmac.tfm =
 485                         ieee80211_aes_cmac_key_setup(key_data, key_len);
 486                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 487                         err = PTR_ERR(key->u.aes_cmac.tfm);
 488                         kfree(key);
 489                         return ERR_PTR(err);
 490                 }
 491                 break;
 492         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 493         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 494                 key->conf.iv_len = 0;
 495                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 496                 if (seq)
 497                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
 498                                 key->u.aes_gmac.rx_pn[j] =
 499                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
 500                 /* Initialize AES key state here as an optimization so that
 501                  * it does not need to be initialized for every packet.
 502                  */
 503                 key->u.aes_gmac.tfm =
 504                         ieee80211_aes_gmac_key_setup(key_data, key_len);
 505                 if (IS_ERR(key->u.aes_gmac.tfm)) {
 506                         err = PTR_ERR(key->u.aes_gmac.tfm);
 507                         kfree(key);
 508                         return ERR_PTR(err);
 509                 }
 510                 break;
 511         case WLAN_CIPHER_SUITE_GCMP:
 512         case WLAN_CIPHER_SUITE_GCMP_256:
 513                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
 514                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
 515                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 516                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
 517                                 key->u.gcmp.rx_pn[i][j] =
 518                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
 519                 /* Initialize AES key state here as an optimization so that
 520                  * it does not need to be initialized for every packet.
 521                  */
 522                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
 523                                                                       key_len);
 524                 if (IS_ERR(key->u.gcmp.tfm)) {
 525                         err = PTR_ERR(key->u.gcmp.tfm);
 526                         kfree(key);
 527                         return ERR_PTR(err);
 528                 }
 529                 break;
 530         default:
 531                 if (cs) {
 532                         if (seq_len && seq_len != cs->pn_len) {
 533                                 kfree(key);
 534                                 return ERR_PTR(-EINVAL);
 535                         }
 536
 537                         key->conf.iv_len = cs->hdr_len;
 538                         key->conf.icv_len = cs->mic_len;
 539                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 540                                 for (j = 0; j < seq_len; j++)
 541                                         key->u.gen.rx_pn[i][j] =
 542                                                         seq[seq_len - j - 1];
 543                         key->flags |= KEY_FLAG_CIPHER_SCHEME;
 544                 }
 545         }
 546         memcpy(key->conf.key, key_data, key_len);
 547         INIT_LIST_HEAD(&key->list);
 548
 549         return key;
 550 }
 551
 552 static void ieee80211_key_free_common(struct ieee80211_key *key)
 553 {
 554         switch (key->conf.cipher) {
 555         case WLAN_CIPHER_SUITE_CCMP:
 556         case WLAN_CIPHER_SUITE_CCMP_256:
 557                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 558                 break;
 559         case WLAN_CIPHER_SUITE_AES_CMAC:
 560         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 561                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 562                 break;
 563         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 564         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 565                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
 566                 break;
 567         case WLAN_CIPHER_SUITE_GCMP:
 568         case WLAN_CIPHER_SUITE_GCMP_256:
 569                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
 570                 break;
 571         }
 572         kzfree(key);
 573 }
 574
 575 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 576                                     bool delay_tailroom)
 577 {
 578         if (key->local)
 579                 ieee80211_key_disable_hw_accel(key);
 580
 581         if (key->local) {
 582                 struct ieee80211_sub_if_data *sdata = key->sdata;
 583
 584                 ieee80211_debugfs_key_remove(key);
 585
 586                 if (delay_tailroom) {
 587                         /* see ieee80211_delayed_tailroom_dec */
 588                         sdata->crypto_tx_tailroom_pending_dec++;
 589                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 590                                               HZ/2);
 591                 } else {
 592                         decrease_tailroom_need_count(sdata, 1);
 593                 }
 594         }
 595
 596         ieee80211_key_free_common(key);
 597 }
 598
 599 static void ieee80211_key_destroy(struct ieee80211_key *key,
 600                                   bool delay_tailroom)
 601 {
 602         if (!key)
 603                 return;
 604
 605         /*
 606          * Synchronize so the TX path and rcu key iterators
 607          * can no longer be using this key before we free/remove it.
 608          */
 609         synchronize_net();
 610
 611         __ieee80211_key_destroy(key, delay_tailroom);
 612 }
 613
 614 void ieee80211_key_free_unused(struct ieee80211_key *key)
 615 {
 616         WARN_ON(key->sdata || key->local);
 617         ieee80211_key_free_common(key);
 618 }
 619
 620 static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
 621                                     struct ieee80211_key *old,
 622                                     struct ieee80211_key *new)
 623 {
 624         u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
 625         u8 *tk_old, *tk_new;
 626
 627         if (!old || new->conf.keylen != old->conf.keylen)
 628                 return false;
 629
 630         tk_old = old->conf.key;
 631         tk_new = new->conf.key;
 632
 633         /*
 634          * In station mode, don't compare the TX MIC key, as it's never used
 635          * and offloaded rekeying may not care to send it to the host. This
 636          * is the case in iwlwifi, for example.
 637          */
 638         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 639             new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
 640             new->conf.keylen == WLAN_KEY_LEN_TKIP &&
 641             !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
 642                 memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
 643                 memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
 644                 memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
 645                 memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
 646                 tk_old = tkip_old;
 647                 tk_new = tkip_new;
 648         }
 649
 650         return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
 651 }
 652
 653 int ieee80211_key_link(struct ieee80211_key *key,
 654                        struct ieee80211_sub_if_data *sdata,
 655                        struct sta_info *sta)
 656 {
 657         struct ieee80211_local *local = sdata->local;
 658         struct ieee80211_key *old_key;
 659         int idx, ret;
 660         bool pairwise;
 661
 662         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 663         idx = key->conf.keyidx;
 664
 665         mutex_lock(&sdata->local->key_mtx);
 666
 667         if (sta && pairwise)
 668                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 669         else if (sta)
 670                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 671         else
 672                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 673
 674         /*
 675          * Silently accept key re-installation without really installing the
 676          * new version of the key to avoid nonce reuse or replay issues.
 677          */
 678         if (ieee80211_key_identical(sdata, old_key, key)) {
 679                 ieee80211_key_free_unused(key);
 680                 ret = 0;
 681                 goto out;
 682         }
 683
 684         key->local = sdata->local;
 685         key->sdata = sdata;
 686         key->sta = sta;
 687
 688         increment_tailroom_need_count(sdata);
 689
 690         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 691         ieee80211_key_destroy(old_key, true);
 692
 693         ieee80211_debugfs_key_add(key);
 694
 695         if (!local->wowlan) {
 696                 ret = ieee80211_key_enable_hw_accel(key);
 697                 if (ret)
 698                         ieee80211_key_free(key, true);
 699         } else {
 700                 ret = 0;
 701         }
 702
 703  out:
 704         mutex_unlock(&sdata->local->key_mtx);
 705
 706         return ret;
 707 }
 708
 709 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 710 {
 711         if (!key)
 712                 return;
 713
 714         /*
 715          * Replace key with nothingness if it was ever used.
 716          */
 717         if (key->sdata)
 718                 ieee80211_key_replace(key->sdata, key->sta,
 719                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 720                                 key, NULL);
 721         ieee80211_key_destroy(key, delay_tailroom);
 722 }
 723
 724 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 725 {
 726         struct ieee80211_key *key;
 727         struct ieee80211_sub_if_data *vlan;
 728
 729         ASSERT_RTNL();
 730
 731         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 732                 return;
 733
 734         mutex_lock(&sdata->local->key_mtx);
 735
 736         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 737                      sdata->crypto_tx_tailroom_pending_dec);
 738
 739         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 740                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 741                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 742                                      vlan->crypto_tx_tailroom_pending_dec);
 743         }
 744
 745         list_for_each_entry(key, &sdata->key_list, list) {
 746                 increment_tailroom_need_count(sdata);
 747                 ieee80211_key_enable_hw_accel(key);
 748         }
 749
 750         mutex_unlock(&sdata->local->key_mtx);
 751 }
 752
 753 void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
 754 {
 755         struct ieee80211_sub_if_data *vlan;
 756
 757         mutex_lock(&sdata->local->key_mtx);
 758
 759         sdata->crypto_tx_tailroom_needed_cnt = 0;
 760
 761         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 762                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 763                         vlan->crypto_tx_tailroom_needed_cnt = 0;
 764         }
 765
 766         mutex_unlock(&sdata->local->key_mtx);
 767 }
 768
 769 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 770                          struct ieee80211_vif *vif,
 771                          void (*iter)(struct ieee80211_hw *hw,
 772                                       struct ieee80211_vif *vif,
 773                                       struct ieee80211_sta *sta,
 774                                       struct ieee80211_key_conf *key,
 775                                       void *data),
 776                          void *iter_data)
 777 {
 778         struct ieee80211_local *local = hw_to_local(hw);
 779         struct ieee80211_key *key, *tmp;
 780         struct ieee80211_sub_if_data *sdata;
 781
 782         ASSERT_RTNL();
 783
 784         mutex_lock(&local->key_mtx);
 785         if (vif) {
 786                 sdata = vif_to_sdata(vif);
 787                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 788                         iter(hw, &sdata->vif,
 789                              key->sta ? &key->sta->sta : NULL,
 790                              &key->conf, iter_data);
 791         } else {
 792                 list_for_each_entry(sdata, &local->interfaces, list)
 793                         list_for_each_entry_safe(key, tmp,
 794                                                  &sdata->key_list, list)
 795                                 iter(hw, &sdata->vif,
 796                                      key->sta ? &key->sta->sta : NULL,
 797                                      &key->conf, iter_data);
 798         }
 799         mutex_unlock(&local->key_mtx);
 800 }
 801 EXPORT_SYMBOL(ieee80211_iter_keys);
 802
 803 static void
 804 _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
 805                          struct ieee80211_sub_if_data *sdata,
 806                          void (*iter)(struct ieee80211_hw *hw,
 807                                       struct ieee80211_vif *vif,
 808                                       struct ieee80211_sta *sta,
 809                                       struct ieee80211_key_conf *key,
 810                                       void *data),
 811                          void *iter_data)
 812 {
 813         struct ieee80211_key *key;
 814
 815         list_for_each_entry_rcu(key, &sdata->key_list, list) {
 816                 /* skip keys of station in removal process */
 817                 if (key->sta && key->sta->removed)
 818                         continue;
 819                 if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 820                         continue;
 821
 822                 iter(hw, &sdata->vif,
 823                      key->sta ? &key->sta->sta : NULL,
 824                      &key->conf, iter_data);
 825         }
 826 }
 827
 828 void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
 829                              struct ieee80211_vif *vif,
 830                              void (*iter)(struct ieee80211_hw *hw,
 831                                           struct ieee80211_vif *vif,
 832                                           struct ieee80211_sta *sta,
 833                                           struct ieee80211_key_conf *key,
 834                                           void *data),
 835                              void *iter_data)
 836 {
 837         struct ieee80211_local *local = hw_to_local(hw);
 838         struct ieee80211_sub_if_data *sdata;
 839
 840         if (vif) {
 841                 sdata = vif_to_sdata(vif);
 842                 _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
 843         } else {
 844                 list_for_each_entry_rcu(sdata, &local->interfaces, list)
 845                         _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
 846         }
 847 }
 848 EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
 849
 850 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 851                                       struct list_head *keys)
 852 {
 853         struct ieee80211_key *key, *tmp;
 854
 855         decrease_tailroom_need_count(sdata,
 856                                      sdata->crypto_tx_tailroom_pending_dec);
 857         sdata->crypto_tx_tailroom_pending_dec = 0;
 858
 859         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 860
 861         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 862                 ieee80211_key_replace(key->sdata, key->sta,
 863                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 864                                 key, NULL);
 865                 list_add_tail(&key->list, keys);
 866         }
 867
 868         ieee80211_debugfs_key_update_default(sdata);
 869 }
 870
 871 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 872                          bool force_synchronize)
 873 {
 874         struct ieee80211_local *local = sdata->local;
 875         struct ieee80211_sub_if_data *vlan;
 876         struct ieee80211_sub_if_data *master;
 877         struct ieee80211_key *key, *tmp;
 878         LIST_HEAD(keys);
 879
 880         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 881
 882         mutex_lock(&local->key_mtx);
 883
 884         ieee80211_free_keys_iface(sdata, &keys);
 885
 886         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 887                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 888                         ieee80211_free_keys_iface(vlan, &keys);
 889         }
 890
 891         if (!list_empty(&keys) || force_synchronize)
 892                 synchronize_net();
 893         list_for_each_entry_safe(key, tmp, &keys, list)
 894                 __ieee80211_key_destroy(key, false);
 895
 896         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 897                 if (sdata->bss) {
 898                         master = container_of(sdata->bss,
 899                                               struct ieee80211_sub_if_data,
 900                                               u.ap);
 901
 902                         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
 903                                      master->crypto_tx_tailroom_needed_cnt);
 904                 }
 905         } else {
 906                 WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 907                              sdata->crypto_tx_tailroom_pending_dec);
 908         }
 909
 910         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 911                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 912                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 913                                      vlan->crypto_tx_tailroom_pending_dec);
 914         }
 915
 916         mutex_unlock(&local->key_mtx);
 917 }
 918
 919 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 920                              struct sta_info *sta)
 921 {
 922         struct ieee80211_key *key;
 923         int i;
 924
 925         mutex_lock(&local->key_mtx);
 926         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 927                 key = key_mtx_dereference(local, sta->gtk[i]);
 928                 if (!key)
 929                         continue;
 930                 ieee80211_key_replace(key->sdata, key->sta,
 931                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 932                                 key, NULL);
 933                 __ieee80211_key_destroy(key, true);
 934         }
 935
 936         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 937                 key = key_mtx_dereference(local, sta->ptk[i]);
 938                 if (!key)
 939                         continue;
 940                 ieee80211_key_replace(key->sdata, key->sta,
 941                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 942                                 key, NULL);
 943                 __ieee80211_key_destroy(key, true);
 944         }
 945
 946         mutex_unlock(&local->key_mtx);
 947 }
 948
 949 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 950 {
 951         struct ieee80211_sub_if_data *sdata;
 952
 953         sdata = container_of(wk, struct ieee80211_sub_if_data,
 954                              dec_tailroom_needed_wk.work);
 955
 956         /*
 957          * The reason for the delayed tailroom needed decrementing is to
 958          * make roaming faster: during roaming, all keys are first deleted
 959          * and then new keys are installed. The first new key causes the
 960          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 961          * the cost of synchronize_net() (which can be slow). Avoid this
 962          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 963          * key removal for a while, so if we roam the value is larger than
 964          * zero and no 0->1 transition happens.
 965          *
 966          * The cost is that if the AP switching was from an AP with keys
 967          * to one without, we still allocate tailroom while it would no
 968          * longer be needed. However, in the typical (fast) roaming case
 969          * within an ESS this usually won't happen.
 970          */
 971
 972         mutex_lock(&sdata->local->key_mtx);
 973         decrease_tailroom_need_count(sdata,
 974                                      sdata->crypto_tx_tailroom_pending_dec);
 975         sdata->crypto_tx_tailroom_pending_dec = 0;
 976         mutex_unlock(&sdata->local->key_mtx);
 977 }
 978
 979 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 980                                 const u8 *replay_ctr, gfp_t gfp)
 981 {
 982         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 983
 984         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 985
 986         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 987 }
 988 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 989
 990 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 991                               int tid, struct ieee80211_key_seq *seq)
 992 {
 993         struct ieee80211_key *key;
 994         const 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                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
1003                 seq->tkip.iv16 = key->u.tkip.rx[tid].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(seq->ccmp.pn, 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(seq->aes_cmac.pn, 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(seq->aes_gmac.pn, 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(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
1038                 break;
1039         }
1040 }
1041 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
1042
1043 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
1044                               int tid, struct ieee80211_key_seq *seq)
1045 {
1046         struct ieee80211_key *key;
1047         u8 *pn;
1048
1049         key = container_of(keyconf, struct ieee80211_key, conf);
1050
1051         switch (key->conf.cipher) {
1052         case WLAN_CIPHER_SUITE_TKIP:
1053                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
1054                         return;
1055                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1056                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1057                 break;
1058         case WLAN_CIPHER_SUITE_CCMP:
1059         case WLAN_CIPHER_SUITE_CCMP_256:
1060                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1061                         return;
1062                 if (tid < 0)
1063                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1064                 else
1065                         pn = key->u.ccmp.rx_pn[tid];
1066                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1067                 break;
1068         case WLAN_CIPHER_SUITE_AES_CMAC:
1069         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1070                 if (WARN_ON(tid != 0))
1071                         return;
1072                 pn = key->u.aes_cmac.rx_pn;
1073                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1074                 break;
1075         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1076         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1077                 if (WARN_ON(tid != 0))
1078                         return;
1079                 pn = key->u.aes_gmac.rx_pn;
1080                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1081                 break;
1082         case WLAN_CIPHER_SUITE_GCMP:
1083         case WLAN_CIPHER_SUITE_GCMP_256:
1084                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1085                         return;
1086                 if (tid < 0)
1087                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1088                 else
1089                         pn = key->u.gcmp.rx_pn[tid];
1090                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1091                 break;
1092         default:
1093                 WARN_ON(1);
1094                 break;
1095         }
1096 }
1097 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1098
1099 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1100 {
1101         struct ieee80211_key *key;
1102
1103         key = container_of(keyconf, struct ieee80211_key, conf);
1104
1105         assert_key_lock(key->local);
1106
1107         /*
1108          * if key was uploaded, we assume the driver will/has remove(d)
1109          * it, so adjust bookkeeping accordingly
1110          */
1111         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1112                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1113
1114                 if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
1115                                            IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
1116                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1117                         increment_tailroom_need_count(key->sdata);
1118         }
1119
1120         ieee80211_key_free(key, false);
1121 }
1122 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1123
1124 struct ieee80211_key_conf *
1125 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1126                         struct ieee80211_key_conf *keyconf)
1127 {
1128         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1129         struct ieee80211_local *local = sdata->local;
1130         struct ieee80211_key *key;
1131         int err;
1132
1133         if (WARN_ON(!local->wowlan))
1134                 return ERR_PTR(-EINVAL);
1135
1136         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1137                 return ERR_PTR(-EINVAL);
1138
1139         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1140                                   keyconf->keylen, keyconf->key,
1141                                   0, NULL, NULL);
1142         if (IS_ERR(key))
1143                 return ERR_CAST(key);
1144
1145         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1146                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1147
1148         err = ieee80211_key_link(key, sdata, NULL);
1149         if (err)
1150                 return ERR_PTR(err);
1151
1152         return &key->conf;
1153 }
1154 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);