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  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/if_ether.h>
  14 #include <linux/etherdevice.h>
  15 #include <linux/list.h>
  16 #include <linux/rcupdate.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <asm/unaligned.h>
  22 #include "ieee80211_i.h"
  23 #include "driver-ops.h"
  24 #include "debugfs_key.h"
  25 #include "aes_ccm.h"
  26 #include "aes_cmac.h"
  27 #include "aes_gmac.h"
  28 #include "aes_gcm.h"
  29
  30
  31 /**
  32  * DOC: Key handling basics
  33  *
  34  * Key handling in mac80211 is done based on per-interface (sub_if_data)
  35  * keys and per-station keys. Since each station belongs to an interface,
  36  * each station key also belongs to that interface.
  37  *
  38  * Hardware acceleration is done on a best-effort basis for algorithms
  39  * that are implemented in software,  for each key the hardware is asked
  40  * to enable that key for offloading but if it cannot do that the key is
  41  * simply kept for software encryption (unless it is for an algorithm
  42  * that isn't implemented in software).
  43  * There is currently no way of knowing whether a key is handled in SW
  44  * or HW except by looking into debugfs.
  45  *
  46  * All key management is internally protected by a mutex. Within all
  47  * other parts of mac80211, key references are, just as STA structure
  48  * references, protected by RCU. Note, however, that some things are
  49  * unprotected, namely the key->sta dereferences within the hardware
  50  * acceleration functions. This means that sta_info_destroy() must
  51  * remove the key which waits for an RCU grace period.
  52  */
  53
  54 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  55
  56 static void assert_key_lock(struct ieee80211_local *local)
  57 {
  58         lockdep_assert_held(&local->key_mtx);
  59 }
  60
  61 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  62 {
  63         /*
  64          * When this count is zero, SKB resizing for allocating tailroom
  65          * for IV or MMIC is skipped. But, this check has created two race
  66          * cases in xmit path while transiting from zero count to one:
  67          *
  68          * 1. SKB resize was skipped because no key was added but just before
  69          * the xmit key is added and SW encryption kicks off.
  70          *
  71          * 2. SKB resize was skipped because all the keys were hw planted but
  72          * just before xmit one of the key is deleted and SW encryption kicks
  73          * off.
  74          *
  75          * In both the above case SW encryption will find not enough space for
  76          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  77          *
  78          * Solution has been explained at
  79          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
  80          */
  81
  82         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
  83                 /*
  84                  * Flush all XMIT packets currently using HW encryption or no
  85                  * encryption at all if the count transition is from 0 -> 1.
  86                  */
  87                 synchronize_net();
  88         }
  89 }
  90
  91 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
  92 {
  93         struct ieee80211_sub_if_data *sdata;
  94         struct sta_info *sta;
  95         int ret = -EOPNOTSUPP;
  96
  97         might_sleep();
  98
  99         if (key->flags & KEY_FLAG_TAINTED) {
 100                 /* If we get here, it's during resume and the key is
 101                  * tainted so shouldn't be used/programmed any more.
 102                  * However, its flags may still indicate that it was
 103                  * programmed into the device (since we're in resume)
 104                  * so clear that flag now to avoid trying to remove
 105                  * it again later.
 106                  */
 107                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 108                 return -EINVAL;
 109         }
 110
 111         if (!key->local->ops->set_key)
 112                 goto out_unsupported;
 113
 114         assert_key_lock(key->local);
 115
 116         sta = key->sta;
 117
 118         /*
 119          * If this is a per-STA GTK, check if it
 120          * is supported; if not, return.
 121          */
 122         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
 123             !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
 124                 goto out_unsupported;
 125
 126         if (sta && !sta->uploaded)
 127                 goto out_unsupported;
 128
 129         sdata = key->sdata;
 130         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 131                 /*
 132                  * The driver doesn't know anything about VLAN interfaces.
 133                  * Hence, don't send GTKs for VLAN interfaces to the driver.
 134                  */
 135                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
 136                         goto out_unsupported;
 137         }
 138
 139         ret = drv_set_key(key->local, SET_KEY, sdata,
 140                           sta ? &sta->sta : NULL, &key->conf);
 141
 142         if (!ret) {
 143                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 144
 145                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 146                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 147                         sdata->crypto_tx_tailroom_needed_cnt--;
 148
 149                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 150                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 151
 152                 return 0;
 153         }
 154
 155         if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
 156                 sdata_err(sdata,
 157                           "failed to set key (%d, %pM) to hardware (%d)\n",
 158                           key->conf.keyidx,
 159                           sta ? sta->sta.addr : bcast_addr, ret);
 160
 161  out_unsupported:
 162         switch (key->conf.cipher) {
 163         case WLAN_CIPHER_SUITE_WEP40:
 164         case WLAN_CIPHER_SUITE_WEP104:
 165         case WLAN_CIPHER_SUITE_TKIP:
 166         case WLAN_CIPHER_SUITE_CCMP:
 167         case WLAN_CIPHER_SUITE_CCMP_256:
 168         case WLAN_CIPHER_SUITE_AES_CMAC:
 169         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 170         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 171         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 172         case WLAN_CIPHER_SUITE_GCMP:
 173         case WLAN_CIPHER_SUITE_GCMP_256:
 174                 /* all of these we can do in software - if driver can */
 175                 if (ret == 1)
 176                         return 0;
 177                 if (key->local->hw.flags & IEEE80211_HW_SW_CRYPTO_CONTROL)
 178                         return -EINVAL;
 179                 return 0;
 180         default:
 181                 return -EINVAL;
 182         }
 183 }
 184
 185 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 186 {
 187         struct ieee80211_sub_if_data *sdata;
 188         struct sta_info *sta;
 189         int ret;
 190
 191         might_sleep();
 192
 193         if (!key || !key->local->ops->set_key)
 194                 return;
 195
 196         assert_key_lock(key->local);
 197
 198         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 199                 return;
 200
 201         sta = key->sta;
 202         sdata = key->sdata;
 203
 204         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 205               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 206                 increment_tailroom_need_count(sdata);
 207
 208         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 209                           sta ? &sta->sta : NULL, &key->conf);
 210
 211         if (ret)
 212                 sdata_err(sdata,
 213                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 214                           key->conf.keyidx,
 215                           sta ? sta->sta.addr : bcast_addr, ret);
 216
 217         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 218 }
 219
 220 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 221                                         int idx, bool uni, bool multi)
 222 {
 223         struct ieee80211_key *key = NULL;
 224
 225         assert_key_lock(sdata->local);
 226
 227         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 228                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 229
 230         if (uni) {
 231                 rcu_assign_pointer(sdata->default_unicast_key, key);
 232                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 233         }
 234
 235         if (multi)
 236                 rcu_assign_pointer(sdata->default_multicast_key, key);
 237
 238         ieee80211_debugfs_key_update_default(sdata);
 239 }
 240
 241 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 242                                bool uni, bool multi)
 243 {
 244         mutex_lock(&sdata->local->key_mtx);
 245         __ieee80211_set_default_key(sdata, idx, uni, multi);
 246         mutex_unlock(&sdata->local->key_mtx);
 247 }
 248
 249 static void
 250 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 251 {
 252         struct ieee80211_key *key = NULL;
 253
 254         assert_key_lock(sdata->local);
 255
 256         if (idx >= NUM_DEFAULT_KEYS &&
 257             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 258                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 259
 260         rcu_assign_pointer(sdata->default_mgmt_key, key);
 261
 262         ieee80211_debugfs_key_update_default(sdata);
 263 }
 264
 265 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 266                                     int idx)
 267 {
 268         mutex_lock(&sdata->local->key_mtx);
 269         __ieee80211_set_default_mgmt_key(sdata, idx);
 270         mutex_unlock(&sdata->local->key_mtx);
 271 }
 272
 273
 274 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 275                                   struct sta_info *sta,
 276                                   bool pairwise,
 277                                   struct ieee80211_key *old,
 278                                   struct ieee80211_key *new)
 279 {
 280         int idx;
 281         bool defunikey, defmultikey, defmgmtkey;
 282
 283         /* caller must provide at least one old/new */
 284         if (WARN_ON(!new && !old))
 285                 return;
 286
 287         if (new)
 288                 list_add_tail(&new->list, &sdata->key_list);
 289
 290         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 291
 292         if (old)
 293                 idx = old->conf.keyidx;
 294         else
 295                 idx = new->conf.keyidx;
 296
 297         if (sta) {
 298                 if (pairwise) {
 299                         rcu_assign_pointer(sta->ptk[idx], new);
 300                         sta->ptk_idx = idx;
 301                 } else {
 302                         rcu_assign_pointer(sta->gtk[idx], new);
 303                         sta->gtk_idx = idx;
 304                 }
 305         } else {
 306                 defunikey = old &&
 307                         old == key_mtx_dereference(sdata->local,
 308                                                 sdata->default_unicast_key);
 309                 defmultikey = old &&
 310                         old == key_mtx_dereference(sdata->local,
 311                                                 sdata->default_multicast_key);
 312                 defmgmtkey = old &&
 313                         old == key_mtx_dereference(sdata->local,
 314                                                 sdata->default_mgmt_key);
 315
 316                 if (defunikey && !new)
 317                         __ieee80211_set_default_key(sdata, -1, true, false);
 318                 if (defmultikey && !new)
 319                         __ieee80211_set_default_key(sdata, -1, false, true);
 320                 if (defmgmtkey && !new)
 321                         __ieee80211_set_default_mgmt_key(sdata, -1);
 322
 323                 rcu_assign_pointer(sdata->keys[idx], new);
 324                 if (defunikey && new)
 325                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 326                                                     true, false);
 327                 if (defmultikey && new)
 328                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 329                                                     false, true);
 330                 if (defmgmtkey && new)
 331                         __ieee80211_set_default_mgmt_key(sdata,
 332                                                          new->conf.keyidx);
 333         }
 334
 335         if (old)
 336                 list_del(&old->list);
 337 }
 338
 339 struct ieee80211_key *
 340 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 341                     const u8 *key_data,
 342                     size_t seq_len, const u8 *seq,
 343                     const struct ieee80211_cipher_scheme *cs)
 344 {
 345         struct ieee80211_key *key;
 346         int i, j, err;
 347
 348         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 349                 return ERR_PTR(-EINVAL);
 350
 351         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 352         if (!key)
 353                 return ERR_PTR(-ENOMEM);
 354
 355         /*
 356          * Default to software encryption; we'll later upload the
 357          * key to the hardware if possible.
 358          */
 359         key->conf.flags = 0;
 360         key->flags = 0;
 361
 362         key->conf.cipher = cipher;
 363         key->conf.keyidx = idx;
 364         key->conf.keylen = key_len;
 365         switch (cipher) {
 366         case WLAN_CIPHER_SUITE_WEP40:
 367         case WLAN_CIPHER_SUITE_WEP104:
 368                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 369                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 370                 break;
 371         case WLAN_CIPHER_SUITE_TKIP:
 372                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 373                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 374                 if (seq) {
 375                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 376                                 key->u.tkip.rx[i].iv32 =
 377                                         get_unaligned_le32(&seq[2]);
 378                                 key->u.tkip.rx[i].iv16 =
 379                                         get_unaligned_le16(seq);
 380                         }
 381                 }
 382                 spin_lock_init(&key->u.tkip.txlock);
 383                 break;
 384         case WLAN_CIPHER_SUITE_CCMP:
 385                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 386                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 387                 if (seq) {
 388                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 389                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 390                                         key->u.ccmp.rx_pn[i][j] =
 391                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 392                 }
 393                 /*
 394                  * Initialize AES key state here as an optimization so that
 395                  * it does not need to be initialized for every packet.
 396                  */
 397                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 398                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
 399                 if (IS_ERR(key->u.ccmp.tfm)) {
 400                         err = PTR_ERR(key->u.ccmp.tfm);
 401                         kfree(key);
 402                         return ERR_PTR(err);
 403                 }
 404                 break;
 405         case WLAN_CIPHER_SUITE_CCMP_256:
 406                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
 407                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
 408                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 409                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
 410                                 key->u.ccmp.rx_pn[i][j] =
 411                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
 412                 /* Initialize AES key state here as an optimization so that
 413                  * it does not need to be initialized for every packet.
 414                  */
 415                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 416                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
 417                 if (IS_ERR(key->u.ccmp.tfm)) {
 418                         err = PTR_ERR(key->u.ccmp.tfm);
 419                         kfree(key);
 420                         return ERR_PTR(err);
 421                 }
 422                 break;
 423         case WLAN_CIPHER_SUITE_AES_CMAC:
 424         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 425                 key->conf.iv_len = 0;
 426                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 427                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
 428                 else
 429                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 430                 if (seq)
 431                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 432                                 key->u.aes_cmac.rx_pn[j] =
 433                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 434                 /*
 435                  * Initialize AES key state here as an optimization so that
 436                  * it does not need to be initialized for every packet.
 437                  */
 438                 key->u.aes_cmac.tfm =
 439                         ieee80211_aes_cmac_key_setup(key_data, key_len);
 440                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 441                         err = PTR_ERR(key->u.aes_cmac.tfm);
 442                         kfree(key);
 443                         return ERR_PTR(err);
 444                 }
 445                 break;
 446         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 447         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 448                 key->conf.iv_len = 0;
 449                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 450                 if (seq)
 451                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
 452                                 key->u.aes_gmac.rx_pn[j] =
 453                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
 454                 /* Initialize AES key state here as an optimization so that
 455                  * it does not need to be initialized for every packet.
 456                  */
 457                 key->u.aes_gmac.tfm =
 458                         ieee80211_aes_gmac_key_setup(key_data, key_len);
 459                 if (IS_ERR(key->u.aes_gmac.tfm)) {
 460                         err = PTR_ERR(key->u.aes_gmac.tfm);
 461                         kfree(key);
 462                         return ERR_PTR(err);
 463                 }
 464                 break;
 465         case WLAN_CIPHER_SUITE_GCMP:
 466         case WLAN_CIPHER_SUITE_GCMP_256:
 467                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
 468                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
 469                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 470                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
 471                                 key->u.gcmp.rx_pn[i][j] =
 472                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
 473                 /* Initialize AES key state here as an optimization so that
 474                  * it does not need to be initialized for every packet.
 475                  */
 476                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
 477                                                                       key_len);
 478                 if (IS_ERR(key->u.gcmp.tfm)) {
 479                         err = PTR_ERR(key->u.gcmp.tfm);
 480                         kfree(key);
 481                         return ERR_PTR(err);
 482                 }
 483                 break;
 484         default:
 485                 if (cs) {
 486                         size_t len = (seq_len > MAX_PN_LEN) ?
 487                                                 MAX_PN_LEN : seq_len;
 488
 489                         key->conf.iv_len = cs->hdr_len;
 490                         key->conf.icv_len = cs->mic_len;
 491                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 492                                 for (j = 0; j < len; j++)
 493                                         key->u.gen.rx_pn[i][j] =
 494                                                         seq[len - j - 1];
 495                 }
 496         }
 497         memcpy(key->conf.key, key_data, key_len);
 498         INIT_LIST_HEAD(&key->list);
 499
 500         return key;
 501 }
 502
 503 static void ieee80211_key_free_common(struct ieee80211_key *key)
 504 {
 505         switch (key->conf.cipher) {
 506         case WLAN_CIPHER_SUITE_CCMP:
 507         case WLAN_CIPHER_SUITE_CCMP_256:
 508                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 509                 break;
 510         case WLAN_CIPHER_SUITE_AES_CMAC:
 511         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 512                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 513                 break;
 514         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 515         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 516                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
 517                 break;
 518         case WLAN_CIPHER_SUITE_GCMP:
 519         case WLAN_CIPHER_SUITE_GCMP_256:
 520                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
 521                 break;
 522         }
 523         kzfree(key);
 524 }
 525
 526 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 527                                     bool delay_tailroom)
 528 {
 529         if (key->local)
 530                 ieee80211_key_disable_hw_accel(key);
 531
 532         if (key->local) {
 533                 struct ieee80211_sub_if_data *sdata = key->sdata;
 534
 535                 ieee80211_debugfs_key_remove(key);
 536
 537                 if (delay_tailroom) {
 538                         /* see ieee80211_delayed_tailroom_dec */
 539                         sdata->crypto_tx_tailroom_pending_dec++;
 540                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 541                                               HZ/2);
 542                 } else {
 543                         sdata->crypto_tx_tailroom_needed_cnt--;
 544                 }
 545         }
 546
 547         ieee80211_key_free_common(key);
 548 }
 549
 550 static void ieee80211_key_destroy(struct ieee80211_key *key,
 551                                   bool delay_tailroom)
 552 {
 553         if (!key)
 554                 return;
 555
 556         /*
 557          * Synchronize so the TX path can no longer be using
 558          * this key before we free/remove it.
 559          */
 560         synchronize_net();
 561
 562         __ieee80211_key_destroy(key, delay_tailroom);
 563 }
 564
 565 void ieee80211_key_free_unused(struct ieee80211_key *key)
 566 {
 567         WARN_ON(key->sdata || key->local);
 568         ieee80211_key_free_common(key);
 569 }
 570
 571 int ieee80211_key_link(struct ieee80211_key *key,
 572                        struct ieee80211_sub_if_data *sdata,
 573                        struct sta_info *sta)
 574 {
 575         struct ieee80211_local *local = sdata->local;
 576         struct ieee80211_key *old_key;
 577         int idx, ret;
 578         bool pairwise;
 579
 580         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 581         idx = key->conf.keyidx;
 582         key->local = sdata->local;
 583         key->sdata = sdata;
 584         key->sta = sta;
 585
 586         mutex_lock(&sdata->local->key_mtx);
 587
 588         if (sta && pairwise)
 589                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 590         else if (sta)
 591                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 592         else
 593                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 594
 595         increment_tailroom_need_count(sdata);
 596
 597         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 598         ieee80211_key_destroy(old_key, true);
 599
 600         ieee80211_debugfs_key_add(key);
 601
 602         if (!local->wowlan) {
 603                 ret = ieee80211_key_enable_hw_accel(key);
 604                 if (ret)
 605                         ieee80211_key_free(key, true);
 606         } else {
 607                 ret = 0;
 608         }
 609
 610         mutex_unlock(&sdata->local->key_mtx);
 611
 612         return ret;
 613 }
 614
 615 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 616 {
 617         if (!key)
 618                 return;
 619
 620         /*
 621          * Replace key with nothingness if it was ever used.
 622          */
 623         if (key->sdata)
 624                 ieee80211_key_replace(key->sdata, key->sta,
 625                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 626                                 key, NULL);
 627         ieee80211_key_destroy(key, delay_tailroom);
 628 }
 629
 630 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 631 {
 632         struct ieee80211_key *key;
 633
 634         ASSERT_RTNL();
 635
 636         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 637                 return;
 638
 639         mutex_lock(&sdata->local->key_mtx);
 640
 641         sdata->crypto_tx_tailroom_needed_cnt = 0;
 642
 643         list_for_each_entry(key, &sdata->key_list, list) {
 644                 increment_tailroom_need_count(sdata);
 645                 ieee80211_key_enable_hw_accel(key);
 646         }
 647
 648         mutex_unlock(&sdata->local->key_mtx);
 649 }
 650
 651 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 652                          struct ieee80211_vif *vif,
 653                          void (*iter)(struct ieee80211_hw *hw,
 654                                       struct ieee80211_vif *vif,
 655                                       struct ieee80211_sta *sta,
 656                                       struct ieee80211_key_conf *key,
 657                                       void *data),
 658                          void *iter_data)
 659 {
 660         struct ieee80211_local *local = hw_to_local(hw);
 661         struct ieee80211_key *key, *tmp;
 662         struct ieee80211_sub_if_data *sdata;
 663
 664         ASSERT_RTNL();
 665
 666         mutex_lock(&local->key_mtx);
 667         if (vif) {
 668                 sdata = vif_to_sdata(vif);
 669                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 670                         iter(hw, &sdata->vif,
 671                              key->sta ? &key->sta->sta : NULL,
 672                              &key->conf, iter_data);
 673         } else {
 674                 list_for_each_entry(sdata, &local->interfaces, list)
 675                         list_for_each_entry_safe(key, tmp,
 676                                                  &sdata->key_list, list)
 677                                 iter(hw, &sdata->vif,
 678                                      key->sta ? &key->sta->sta : NULL,
 679                                      &key->conf, iter_data);
 680         }
 681         mutex_unlock(&local->key_mtx);
 682 }
 683 EXPORT_SYMBOL(ieee80211_iter_keys);
 684
 685 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 686                                       struct list_head *keys)
 687 {
 688         struct ieee80211_key *key, *tmp;
 689
 690         sdata->crypto_tx_tailroom_needed_cnt -=
 691                 sdata->crypto_tx_tailroom_pending_dec;
 692         sdata->crypto_tx_tailroom_pending_dec = 0;
 693
 694         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 695
 696         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 697                 ieee80211_key_replace(key->sdata, key->sta,
 698                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 699                                 key, NULL);
 700                 list_add_tail(&key->list, keys);
 701         }
 702
 703         ieee80211_debugfs_key_update_default(sdata);
 704 }
 705
 706 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 707                          bool force_synchronize)
 708 {
 709         struct ieee80211_local *local = sdata->local;
 710         struct ieee80211_sub_if_data *vlan;
 711         struct ieee80211_key *key, *tmp;
 712         LIST_HEAD(keys);
 713
 714         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 715
 716         mutex_lock(&local->key_mtx);
 717
 718         ieee80211_free_keys_iface(sdata, &keys);
 719
 720         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 721                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 722                         ieee80211_free_keys_iface(vlan, &keys);
 723         }
 724
 725         if (!list_empty(&keys) || force_synchronize)
 726                 synchronize_net();
 727         list_for_each_entry_safe(key, tmp, &keys, list)
 728                 __ieee80211_key_destroy(key, false);
 729
 730         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 731                      sdata->crypto_tx_tailroom_pending_dec);
 732         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 733                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 734                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 735                                      vlan->crypto_tx_tailroom_pending_dec);
 736         }
 737
 738         mutex_unlock(&local->key_mtx);
 739 }
 740
 741 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 742                              struct sta_info *sta)
 743 {
 744         struct ieee80211_key *key;
 745         int i;
 746
 747         mutex_lock(&local->key_mtx);
 748         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 749                 key = key_mtx_dereference(local, sta->gtk[i]);
 750                 if (!key)
 751                         continue;
 752                 ieee80211_key_replace(key->sdata, key->sta,
 753                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 754                                 key, NULL);
 755                 __ieee80211_key_destroy(key, true);
 756         }
 757
 758         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 759                 key = key_mtx_dereference(local, sta->ptk[i]);
 760                 if (!key)
 761                         continue;
 762                 ieee80211_key_replace(key->sdata, key->sta,
 763                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 764                                 key, NULL);
 765                 __ieee80211_key_destroy(key, true);
 766         }
 767
 768         mutex_unlock(&local->key_mtx);
 769 }
 770
 771 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 772 {
 773         struct ieee80211_sub_if_data *sdata;
 774
 775         sdata = container_of(wk, struct ieee80211_sub_if_data,
 776                              dec_tailroom_needed_wk.work);
 777
 778         /*
 779          * The reason for the delayed tailroom needed decrementing is to
 780          * make roaming faster: during roaming, all keys are first deleted
 781          * and then new keys are installed. The first new key causes the
 782          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 783          * the cost of synchronize_net() (which can be slow). Avoid this
 784          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 785          * key removal for a while, so if we roam the value is larger than
 786          * zero and no 0->1 transition happens.
 787          *
 788          * The cost is that if the AP switching was from an AP with keys
 789          * to one without, we still allocate tailroom while it would no
 790          * longer be needed. However, in the typical (fast) roaming case
 791          * within an ESS this usually won't happen.
 792          */
 793
 794         mutex_lock(&sdata->local->key_mtx);
 795         sdata->crypto_tx_tailroom_needed_cnt -=
 796                 sdata->crypto_tx_tailroom_pending_dec;
 797         sdata->crypto_tx_tailroom_pending_dec = 0;
 798         mutex_unlock(&sdata->local->key_mtx);
 799 }
 800
 801 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 802                                 const u8 *replay_ctr, gfp_t gfp)
 803 {
 804         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 805
 806         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 807
 808         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 809 }
 810 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 811
 812 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
 813                               struct ieee80211_key_seq *seq)
 814 {
 815         struct ieee80211_key *key;
 816         u64 pn64;
 817
 818         if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
 819                 return;
 820
 821         key = container_of(keyconf, struct ieee80211_key, conf);
 822
 823         switch (key->conf.cipher) {
 824         case WLAN_CIPHER_SUITE_TKIP:
 825                 seq->tkip.iv32 = key->u.tkip.tx.iv32;
 826                 seq->tkip.iv16 = key->u.tkip.tx.iv16;
 827                 break;
 828         case WLAN_CIPHER_SUITE_CCMP:
 829         case WLAN_CIPHER_SUITE_CCMP_256:
 830                 pn64 = atomic64_read(&key->u.ccmp.tx_pn);
 831                 seq->ccmp.pn[5] = pn64;
 832                 seq->ccmp.pn[4] = pn64 >> 8;
 833                 seq->ccmp.pn[3] = pn64 >> 16;
 834                 seq->ccmp.pn[2] = pn64 >> 24;
 835                 seq->ccmp.pn[1] = pn64 >> 32;
 836                 seq->ccmp.pn[0] = pn64 >> 40;
 837                 break;
 838         case WLAN_CIPHER_SUITE_AES_CMAC:
 839         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 840                 pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
 841                 seq->ccmp.pn[5] = pn64;
 842                 seq->ccmp.pn[4] = pn64 >> 8;
 843                 seq->ccmp.pn[3] = pn64 >> 16;
 844                 seq->ccmp.pn[2] = pn64 >> 24;
 845                 seq->ccmp.pn[1] = pn64 >> 32;
 846                 seq->ccmp.pn[0] = pn64 >> 40;
 847                 break;
 848         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 849         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 850                 pn64 = atomic64_read(&key->u.aes_gmac.tx_pn);
 851                 seq->ccmp.pn[5] = pn64;
 852                 seq->ccmp.pn[4] = pn64 >> 8;
 853                 seq->ccmp.pn[3] = pn64 >> 16;
 854                 seq->ccmp.pn[2] = pn64 >> 24;
 855                 seq->ccmp.pn[1] = pn64 >> 32;
 856                 seq->ccmp.pn[0] = pn64 >> 40;
 857                 break;
 858         case WLAN_CIPHER_SUITE_GCMP:
 859         case WLAN_CIPHER_SUITE_GCMP_256:
 860                 pn64 = atomic64_read(&key->u.gcmp.tx_pn);
 861                 seq->gcmp.pn[5] = pn64;
 862                 seq->gcmp.pn[4] = pn64 >> 8;
 863                 seq->gcmp.pn[3] = pn64 >> 16;
 864                 seq->gcmp.pn[2] = pn64 >> 24;
 865                 seq->gcmp.pn[1] = pn64 >> 32;
 866                 seq->gcmp.pn[0] = pn64 >> 40;
 867                 break;
 868         default:
 869                 WARN_ON(1);
 870         }
 871 }
 872 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
 873
 874 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 875                               int tid, struct ieee80211_key_seq *seq)
 876 {
 877         struct ieee80211_key *key;
 878         const u8 *pn;
 879
 880         key = container_of(keyconf, struct ieee80211_key, conf);
 881
 882         switch (key->conf.cipher) {
 883         case WLAN_CIPHER_SUITE_TKIP:
 884                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 885                         return;
 886                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
 887                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
 888                 break;
 889         case WLAN_CIPHER_SUITE_CCMP:
 890         case WLAN_CIPHER_SUITE_CCMP_256:
 891                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 892                         return;
 893                 if (tid < 0)
 894                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 895                 else
 896                         pn = key->u.ccmp.rx_pn[tid];
 897                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
 898                 break;
 899         case WLAN_CIPHER_SUITE_AES_CMAC:
 900         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 901                 if (WARN_ON(tid != 0))
 902                         return;
 903                 pn = key->u.aes_cmac.rx_pn;
 904                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
 905                 break;
 906         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 907         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 908                 if (WARN_ON(tid != 0))
 909                         return;
 910                 pn = key->u.aes_gmac.rx_pn;
 911                 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
 912                 break;
 913         case WLAN_CIPHER_SUITE_GCMP:
 914         case WLAN_CIPHER_SUITE_GCMP_256:
 915                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 916                         return;
 917                 if (tid < 0)
 918                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
 919                 else
 920                         pn = key->u.gcmp.rx_pn[tid];
 921                 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
 922                 break;
 923         }
 924 }
 925 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
 926
 927 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
 928                               struct ieee80211_key_seq *seq)
 929 {
 930         struct ieee80211_key *key;
 931         u64 pn64;
 932
 933         key = container_of(keyconf, struct ieee80211_key, conf);
 934
 935         switch (key->conf.cipher) {
 936         case WLAN_CIPHER_SUITE_TKIP:
 937                 key->u.tkip.tx.iv32 = seq->tkip.iv32;
 938                 key->u.tkip.tx.iv16 = seq->tkip.iv16;
 939                 break;
 940         case WLAN_CIPHER_SUITE_CCMP:
 941         case WLAN_CIPHER_SUITE_CCMP_256:
 942                 pn64 = (u64)seq->ccmp.pn[5] |
 943                        ((u64)seq->ccmp.pn[4] << 8) |
 944                        ((u64)seq->ccmp.pn[3] << 16) |
 945                        ((u64)seq->ccmp.pn[2] << 24) |
 946                        ((u64)seq->ccmp.pn[1] << 32) |
 947                        ((u64)seq->ccmp.pn[0] << 40);
 948                 atomic64_set(&key->u.ccmp.tx_pn, pn64);
 949                 break;
 950         case WLAN_CIPHER_SUITE_AES_CMAC:
 951         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 952                 pn64 = (u64)seq->aes_cmac.pn[5] |
 953                        ((u64)seq->aes_cmac.pn[4] << 8) |
 954                        ((u64)seq->aes_cmac.pn[3] << 16) |
 955                        ((u64)seq->aes_cmac.pn[2] << 24) |
 956                        ((u64)seq->aes_cmac.pn[1] << 32) |
 957                        ((u64)seq->aes_cmac.pn[0] << 40);
 958                 atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
 959                 break;
 960         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 961         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 962                 pn64 = (u64)seq->aes_gmac.pn[5] |
 963                        ((u64)seq->aes_gmac.pn[4] << 8) |
 964                        ((u64)seq->aes_gmac.pn[3] << 16) |
 965                        ((u64)seq->aes_gmac.pn[2] << 24) |
 966                        ((u64)seq->aes_gmac.pn[1] << 32) |
 967                        ((u64)seq->aes_gmac.pn[0] << 40);
 968                 atomic64_set(&key->u.aes_gmac.tx_pn, pn64);
 969                 break;
 970         case WLAN_CIPHER_SUITE_GCMP:
 971         case WLAN_CIPHER_SUITE_GCMP_256:
 972                 pn64 = (u64)seq->gcmp.pn[5] |
 973                        ((u64)seq->gcmp.pn[4] << 8) |
 974                        ((u64)seq->gcmp.pn[3] << 16) |
 975                        ((u64)seq->gcmp.pn[2] << 24) |
 976                        ((u64)seq->gcmp.pn[1] << 32) |
 977                        ((u64)seq->gcmp.pn[0] << 40);
 978                 atomic64_set(&key->u.gcmp.tx_pn, pn64);
 979                 break;
 980         default:
 981                 WARN_ON(1);
 982                 break;
 983         }
 984 }
 985 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
 986
 987 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
 988                               int tid, struct ieee80211_key_seq *seq)
 989 {
 990         struct ieee80211_key *key;
 991         u8 *pn;
 992
 993         key = container_of(keyconf, struct ieee80211_key, conf);
 994
 995         switch (key->conf.cipher) {
 996         case WLAN_CIPHER_SUITE_TKIP:
 997                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 998                         return;
 999                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
1000                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
1001                 break;
1002         case WLAN_CIPHER_SUITE_CCMP:
1003         case WLAN_CIPHER_SUITE_CCMP_256:
1004                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1005                         return;
1006                 if (tid < 0)
1007                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
1008                 else
1009                         pn = key->u.ccmp.rx_pn[tid];
1010                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
1011                 break;
1012         case WLAN_CIPHER_SUITE_AES_CMAC:
1013         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1014                 if (WARN_ON(tid != 0))
1015                         return;
1016                 pn = key->u.aes_cmac.rx_pn;
1017                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
1018                 break;
1019         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1020         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1021                 if (WARN_ON(tid != 0))
1022                         return;
1023                 pn = key->u.aes_gmac.rx_pn;
1024                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
1025                 break;
1026         case WLAN_CIPHER_SUITE_GCMP:
1027         case WLAN_CIPHER_SUITE_GCMP_256:
1028                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
1029                         return;
1030                 if (tid < 0)
1031                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1032                 else
1033                         pn = key->u.gcmp.rx_pn[tid];
1034                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1035                 break;
1036         default:
1037                 WARN_ON(1);
1038                 break;
1039         }
1040 }
1041 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1042
1043 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1044 {
1045         struct ieee80211_key *key;
1046
1047         key = container_of(keyconf, struct ieee80211_key, conf);
1048
1049         assert_key_lock(key->local);
1050
1051         /*
1052          * if key was uploaded, we assume the driver will/has remove(d)
1053          * it, so adjust bookkeeping accordingly
1054          */
1055         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1056                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1057
1058                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
1059                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1060                         increment_tailroom_need_count(key->sdata);
1061         }
1062
1063         ieee80211_key_free(key, false);
1064 }
1065 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1066
1067 struct ieee80211_key_conf *
1068 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1069                         struct ieee80211_key_conf *keyconf)
1070 {
1071         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1072         struct ieee80211_local *local = sdata->local;
1073         struct ieee80211_key *key;
1074         int err;
1075
1076         if (WARN_ON(!local->wowlan))
1077                 return ERR_PTR(-EINVAL);
1078
1079         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1080                 return ERR_PTR(-EINVAL);
1081
1082         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1083                                   keyconf->keylen, keyconf->key,
1084                                   0, NULL, NULL);
1085         if (IS_ERR(key))
1086                 return ERR_CAST(key);
1087
1088         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1089                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1090
1091         err = ieee80211_key_link(key, sdata, NULL);
1092         if (err)
1093                 return ERR_PTR(err);
1094
1095         return &key->conf;
1096 }
1097 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);