drivers/net/wireless/ath/key.c

   1 /*
   2  * Copyright (c) 2009 Atheros Communications Inc.
   3  * Copyright (c) 2010 Bruno Randolf <br1@einfach.org>
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include <asm/unaligned.h>
  19 #include <net/mac80211.h>
  20
  21 #include "ath.h"
  22 #include "reg.h"
  23 #include "debug.h"
  24
  25 #define REG_READ                        (common->ops->read)
  26 #define REG_WRITE(_ah, _reg, _val)      (common->ops->write)(_ah, _val, _reg)
  27
  28 #define IEEE80211_WEP_NKID      4       /* number of key ids */
  29
  30 /************************/
  31 /* Key Cache Management */
  32 /************************/
  33
  34 bool ath_hw_keyreset(struct ath_common *common, u16 entry)
  35 {
  36         u32 keyType;
  37         void *ah = common->ah;
  38
  39         if (entry >= common->keymax) {
  40                 ath_print(common, ATH_DBG_FATAL,
  41                           "keychache entry %u out of range\n", entry);
  42                 return false;
  43         }
  44
  45         keyType = REG_READ(ah, AR_KEYTABLE_TYPE(entry));
  46
  47         REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
  48         REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
  49         REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
  50         REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
  51         REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
  52         REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
  53         REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
  54         REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);
  55
  56         if (keyType == AR_KEYTABLE_TYPE_TKIP) {
  57                 u16 micentry = entry + 64;
  58
  59                 REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
  60                 REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
  61                 REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
  62                 REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
  63
  64         }
  65
  66         return true;
  67 }
  68 EXPORT_SYMBOL(ath_hw_keyreset);
  69
  70 static bool ath_hw_keysetmac(struct ath_common *common,
  71                              u16 entry, const u8 *mac)
  72 {
  73         u32 macHi, macLo;
  74         u32 unicast_flag = AR_KEYTABLE_VALID;
  75         void *ah = common->ah;
  76
  77         if (entry >= common->keymax) {
  78                 ath_print(common, ATH_DBG_FATAL,
  79                           "keychache entry %u out of range\n", entry);
  80                 return false;
  81         }
  82
  83         if (mac != NULL) {
  84                 /*
  85                  * AR_KEYTABLE_VALID indicates that the address is a unicast
  86                  * address, which must match the transmitter address for
  87                  * decrypting frames.
  88                  * Not setting this bit allows the hardware to use the key
  89                  * for multicast frame decryption.
  90                  */
  91                 if (mac[0] & 0x01)
  92                         unicast_flag = 0;
  93
  94                 macHi = (mac[5] << 8) | mac[4];
  95                 macLo = (mac[3] << 24) |
  96                         (mac[2] << 16) |
  97                         (mac[1] << 8) |
  98                         mac[0];
  99                 macLo >>= 1;
 100                 macLo |= (macHi & 1) << 31;
 101                 macHi >>= 1;
 102         } else {
 103                 macLo = macHi = 0;
 104         }
 105         REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
 106         REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);
 107
 108         return true;
 109 }
 110
 111 bool ath_hw_set_keycache_entry(struct ath_common *common, u16 entry,
 112                                  const struct ath_keyval *k,
 113                                  const u8 *mac)
 114 {
 115         void *ah = common->ah;
 116         u32 key0, key1, key2, key3, key4;
 117         u32 keyType;
 118
 119         if (entry >= common->keymax) {
 120                 ath_print(common, ATH_DBG_FATAL,
 121                           "keycache entry %u out of range\n", entry);
 122                 return false;
 123         }
 124
 125         switch (k->kv_type) {
 126         case ATH_CIPHER_AES_OCB:
 127                 keyType = AR_KEYTABLE_TYPE_AES;
 128                 break;
 129         case ATH_CIPHER_AES_CCM:
 130                 if (!(common->crypt_caps & ATH_CRYPT_CAP_CIPHER_AESCCM)) {
 131                         ath_print(common, ATH_DBG_ANY,
 132                                   "AES-CCM not supported by this mac rev\n");
 133                         return false;
 134                 }
 135                 keyType = AR_KEYTABLE_TYPE_CCM;
 136                 break;
 137         case ATH_CIPHER_TKIP:
 138                 keyType = AR_KEYTABLE_TYPE_TKIP;
 139                 if (entry + 64 >= common->keymax) {
 140                         ath_print(common, ATH_DBG_ANY,
 141                                   "entry %u inappropriate for TKIP\n", entry);
 142                         return false;
 143                 }
 144                 break;
 145         case ATH_CIPHER_WEP:
 146                 if (k->kv_len < WLAN_KEY_LEN_WEP40) {
 147                         ath_print(common, ATH_DBG_ANY,
 148                                   "WEP key length %u too small\n", k->kv_len);
 149                         return false;
 150                 }
 151                 if (k->kv_len <= WLAN_KEY_LEN_WEP40)
 152                         keyType = AR_KEYTABLE_TYPE_40;
 153                 else if (k->kv_len <= WLAN_KEY_LEN_WEP104)
 154                         keyType = AR_KEYTABLE_TYPE_104;
 155                 else
 156                         keyType = AR_KEYTABLE_TYPE_128;
 157                 break;
 158         case ATH_CIPHER_CLR:
 159                 keyType = AR_KEYTABLE_TYPE_CLR;
 160                 break;
 161         default:
 162                 ath_print(common, ATH_DBG_FATAL,
 163                           "cipher %u not supported\n", k->kv_type);
 164                 return false;
 165         }
 166
 167         key0 = get_unaligned_le32(k->kv_val + 0);
 168         key1 = get_unaligned_le16(k->kv_val + 4);
 169         key2 = get_unaligned_le32(k->kv_val + 6);
 170         key3 = get_unaligned_le16(k->kv_val + 10);
 171         key4 = get_unaligned_le32(k->kv_val + 12);
 172         if (k->kv_len <= WLAN_KEY_LEN_WEP104)
 173                 key4 &= 0xff;
 174
 175         /*
 176          * Note: Key cache registers access special memory area that requires
 177          * two 32-bit writes to actually update the values in the internal
 178          * memory. Consequently, the exact order and pairs used here must be
 179          * maintained.
 180          */
 181
 182         if (keyType == AR_KEYTABLE_TYPE_TKIP) {
 183                 u16 micentry = entry + 64;
 184
 185                 /*
 186                  * Write inverted key[47:0] first to avoid Michael MIC errors
 187                  * on frames that could be sent or received at the same time.
 188                  * The correct key will be written in the end once everything
 189                  * else is ready.
 190                  */
 191                 REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
 192                 REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);
 193
 194                 /* Write key[95:48] */
 195                 REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
 196                 REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
 197
 198                 /* Write key[127:96] and key type */
 199                 REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
 200                 REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
 201
 202                 /* Write MAC address for the entry */
 203                 (void) ath_hw_keysetmac(common, entry, mac);
 204
 205                 if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
 206                         /*
 207                          * TKIP uses two key cache entries:
 208                          * Michael MIC TX/RX keys in the same key cache entry
 209                          * (idx = main index + 64):
 210                          * key0 [31:0] = RX key [31:0]
 211                          * key1 [15:0] = TX key [31:16]
 212                          * key1 [31:16] = reserved
 213                          * key2 [31:0] = RX key [63:32]
 214                          * key3 [15:0] = TX key [15:0]
 215                          * key3 [31:16] = reserved
 216                          * key4 [31:0] = TX key [63:32]
 217                          */
 218                         u32 mic0, mic1, mic2, mic3, mic4;
 219
 220                         mic0 = get_unaligned_le32(k->kv_mic + 0);
 221                         mic2 = get_unaligned_le32(k->kv_mic + 4);
 222                         mic1 = get_unaligned_le16(k->kv_txmic + 2) & 0xffff;
 223                         mic3 = get_unaligned_le16(k->kv_txmic + 0) & 0xffff;
 224                         mic4 = get_unaligned_le32(k->kv_txmic + 4);
 225
 226                         /* Write RX[31:0] and TX[31:16] */
 227                         REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
 228                         REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);
 229
 230                         /* Write RX[63:32] and TX[15:0] */
 231                         REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
 232                         REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);
 233
 234                         /* Write TX[63:32] and keyType(reserved) */
 235                         REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
 236                         REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
 237                                   AR_KEYTABLE_TYPE_CLR);
 238
 239                 } else {
 240                         /*
 241                          * TKIP uses four key cache entries (two for group
 242                          * keys):
 243                          * Michael MIC TX/RX keys are in different key cache
 244                          * entries (idx = main index + 64 for TX and
 245                          * main index + 32 + 96 for RX):
 246                          * key0 [31:0] = TX/RX MIC key [31:0]
 247                          * key1 [31:0] = reserved
 248                          * key2 [31:0] = TX/RX MIC key [63:32]
 249                          * key3 [31:0] = reserved
 250                          * key4 [31:0] = reserved
 251                          *
 252                          * Upper layer code will call this function separately
 253                          * for TX and RX keys when these registers offsets are
 254                          * used.
 255                          */
 256                         u32 mic0, mic2;
 257
 258                         mic0 = get_unaligned_le32(k->kv_mic + 0);
 259                         mic2 = get_unaligned_le32(k->kv_mic + 4);
 260
 261                         /* Write MIC key[31:0] */
 262                         REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
 263                         REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
 264
 265                         /* Write MIC key[63:32] */
 266                         REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
 267                         REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
 268
 269                         /* Write TX[63:32] and keyType(reserved) */
 270                         REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0);
 271                         REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
 272                                   AR_KEYTABLE_TYPE_CLR);
 273                 }
 274
 275                 /* MAC address registers are reserved for the MIC entry */
 276                 REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
 277                 REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);
 278
 279                 /*
 280                  * Write the correct (un-inverted) key[47:0] last to enable
 281                  * TKIP now that all other registers are set with correct
 282                  * values.
 283                  */
 284                 REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
 285                 REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
 286         } else {
 287                 /* Write key[47:0] */
 288                 REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
 289                 REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
 290
 291                 /* Write key[95:48] */
 292                 REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
 293                 REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
 294
 295                 /* Write key[127:96] and key type */
 296                 REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
 297                 REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
 298
 299                 /* Write MAC address for the entry */
 300                 (void) ath_hw_keysetmac(common, entry, mac);
 301         }
 302
 303         return true;
 304 }
 305
 306 static int ath_setkey_tkip(struct ath_common *common, u16 keyix, const u8 *key,
 307                            struct ath_keyval *hk, const u8 *addr,
 308                            bool authenticator)
 309 {
 310         const u8 *key_rxmic;
 311         const u8 *key_txmic;
 312
 313         key_txmic = key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
 314         key_rxmic = key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
 315
 316         if (addr == NULL) {
 317                 /*
 318                  * Group key installation - only two key cache entries are used
 319                  * regardless of splitmic capability since group key is only
 320                  * used either for TX or RX.
 321                  */
 322                 if (authenticator) {
 323                         memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 324                         memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_mic));
 325                 } else {
 326                         memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 327                         memcpy(hk->kv_txmic, key_rxmic, sizeof(hk->kv_mic));
 328                 }
 329                 return ath_hw_set_keycache_entry(common, keyix, hk, addr);
 330         }
 331         if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
 332                 /* TX and RX keys share the same key cache entry. */
 333                 memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 334                 memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_txmic));
 335                 return ath_hw_set_keycache_entry(common, keyix, hk, addr);
 336         }
 337
 338         /* Separate key cache entries for TX and RX */
 339
 340         /* TX key goes at first index, RX key at +32. */
 341         memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 342         if (!ath_hw_set_keycache_entry(common, keyix, hk, NULL)) {
 343                 /* TX MIC entry failed. No need to proceed further */
 344                 ath_print(common, ATH_DBG_FATAL,
 345                           "Setting TX MIC Key Failed\n");
 346                 return 0;
 347         }
 348
 349         memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 350         /* XXX delete tx key on failure? */
 351         return ath_hw_set_keycache_entry(common, keyix + 32, hk, addr);
 352 }
 353
 354 static int ath_reserve_key_cache_slot_tkip(struct ath_common *common)
 355 {
 356         int i;
 357
 358         for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 359                 if (test_bit(i, common->keymap) ||
 360                     test_bit(i + 64, common->keymap))
 361                         continue; /* At least one part of TKIP key allocated */
 362                 if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) &&
 363                     (test_bit(i + 32, common->keymap) ||
 364                      test_bit(i + 64 + 32, common->keymap)))
 365                         continue; /* At least one part of TKIP key allocated */
 366
 367                 /* Found a free slot for a TKIP key */
 368                 return i;
 369         }
 370         return -1;
 371 }
 372
 373 static int ath_reserve_key_cache_slot(struct ath_common *common,
 374                                       u32 cipher)
 375 {
 376         int i;
 377
 378         if (cipher == WLAN_CIPHER_SUITE_TKIP)
 379                 return ath_reserve_key_cache_slot_tkip(common);
 380
 381         /* First, try to find slots that would not be available for TKIP. */
 382         if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 383                 for (i = IEEE80211_WEP_NKID; i < common->keymax / 4; i++) {
 384                         if (!test_bit(i, common->keymap) &&
 385                             (test_bit(i + 32, common->keymap) ||
 386                              test_bit(i + 64, common->keymap) ||
 387                              test_bit(i + 64 + 32, common->keymap)))
 388                                 return i;
 389                         if (!test_bit(i + 32, common->keymap) &&
 390                             (test_bit(i, common->keymap) ||
 391                              test_bit(i + 64, common->keymap) ||
 392                              test_bit(i + 64 + 32, common->keymap)))
 393                                 return i + 32;
 394                         if (!test_bit(i + 64, common->keymap) &&
 395                             (test_bit(i , common->keymap) ||
 396                              test_bit(i + 32, common->keymap) ||
 397                              test_bit(i + 64 + 32, common->keymap)))
 398                                 return i + 64;
 399                         if (!test_bit(i + 64 + 32, common->keymap) &&
 400                             (test_bit(i, common->keymap) ||
 401                              test_bit(i + 32, common->keymap) ||
 402                              test_bit(i + 64, common->keymap)))
 403                                 return i + 64 + 32;
 404                 }
 405         } else {
 406                 for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 407                         if (!test_bit(i, common->keymap) &&
 408                             test_bit(i + 64, common->keymap))
 409                                 return i;
 410                         if (test_bit(i, common->keymap) &&
 411                             !test_bit(i + 64, common->keymap))
 412                                 return i + 64;
 413                 }
 414         }
 415
 416         /* No partially used TKIP slots, pick any available slot */
 417         for (i = IEEE80211_WEP_NKID; i < common->keymax; i++) {
 418                 /* Do not allow slots that could be needed for TKIP group keys
 419                  * to be used. This limitation could be removed if we know that
 420                  * TKIP will not be used. */
 421                 if (i >= 64 && i < 64 + IEEE80211_WEP_NKID)
 422                         continue;
 423                 if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 424                         if (i >= 32 && i < 32 + IEEE80211_WEP_NKID)
 425                                 continue;
 426                         if (i >= 64 + 32 && i < 64 + 32 + IEEE80211_WEP_NKID)
 427                                 continue;
 428                 }
 429
 430                 if (!test_bit(i, common->keymap))
 431                         return i; /* Found a free slot for a key */
 432         }
 433
 434         /* No free slot found */
 435         return -1;
 436 }
 437
 438 /*
 439  * Configure encryption in the HW.
 440  */
 441 int ath_key_config(struct ath_common *common,
 442                           struct ieee80211_vif *vif,
 443                           struct ieee80211_sta *sta,
 444                           struct ieee80211_key_conf *key)
 445 {
 446         struct ath_keyval hk;
 447         const u8 *mac = NULL;
 448         u8 gmac[ETH_ALEN];
 449         int ret = 0;
 450         int idx;
 451
 452         memset(&hk, 0, sizeof(hk));
 453
 454         switch (key->cipher) {
 455         case WLAN_CIPHER_SUITE_WEP40:
 456         case WLAN_CIPHER_SUITE_WEP104:
 457                 hk.kv_type = ATH_CIPHER_WEP;
 458                 break;
 459         case WLAN_CIPHER_SUITE_TKIP:
 460                 hk.kv_type = ATH_CIPHER_TKIP;
 461                 break;
 462         case WLAN_CIPHER_SUITE_CCMP:
 463                 hk.kv_type = ATH_CIPHER_AES_CCM;
 464                 break;
 465         default:
 466                 return -EOPNOTSUPP;
 467         }
 468
 469         hk.kv_len = key->keylen;
 470         memcpy(hk.kv_val, key->key, key->keylen);
 471
 472         if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
 473                 switch (vif->type) {
 474                 case NL80211_IFTYPE_AP:
 475                         memcpy(gmac, vif->addr, ETH_ALEN);
 476                         gmac[0] |= 0x01;
 477                         mac = gmac;
 478                         idx = ath_reserve_key_cache_slot(common, key->cipher);
 479                         break;
 480                 case NL80211_IFTYPE_ADHOC:
 481                         if (!sta) {
 482                                 idx = key->keyidx;
 483                                 break;
 484                         }
 485                         memcpy(gmac, sta->addr, ETH_ALEN);
 486                         gmac[0] |= 0x01;
 487                         mac = gmac;
 488                         idx = ath_reserve_key_cache_slot(common, key->cipher);
 489                         break;
 490                 default:
 491                         idx = key->keyidx;
 492                         break;
 493                 }
 494         } else if (key->keyidx) {
 495                 if (WARN_ON(!sta))
 496                         return -EOPNOTSUPP;
 497                 mac = sta->addr;
 498
 499                 if (vif->type != NL80211_IFTYPE_AP) {
 500                         /* Only keyidx 0 should be used with unicast key, but
 501                          * allow this for client mode for now. */
 502                         idx = key->keyidx;
 503                 } else
 504                         return -EIO;
 505         } else {
 506                 if (WARN_ON(!sta))
 507                         return -EOPNOTSUPP;
 508                 mac = sta->addr;
 509
 510                 idx = ath_reserve_key_cache_slot(common, key->cipher);
 511         }
 512
 513         if (idx < 0)
 514                 return -ENOSPC; /* no free key cache entries */
 515
 516         if (key->cipher == WLAN_CIPHER_SUITE_TKIP)
 517                 ret = ath_setkey_tkip(common, idx, key->key, &hk, mac,
 518                                       vif->type == NL80211_IFTYPE_AP);
 519         else
 520                 ret = ath_hw_set_keycache_entry(common, idx, &hk, mac);
 521
 522         if (!ret)
 523                 return -EIO;
 524
 525         set_bit(idx, common->keymap);
 526         if (key->cipher == WLAN_CIPHER_SUITE_TKIP) {
 527                 set_bit(idx + 64, common->keymap);
 528                 set_bit(idx, common->tkip_keymap);
 529                 set_bit(idx + 64, common->tkip_keymap);
 530                 if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 531                         set_bit(idx + 32, common->keymap);
 532                         set_bit(idx + 64 + 32, common->keymap);
 533                         set_bit(idx + 32, common->tkip_keymap);
 534                         set_bit(idx + 64 + 32, common->tkip_keymap);
 535                 }
 536         }
 537
 538         return idx;
 539 }
 540 EXPORT_SYMBOL(ath_key_config);
 541
 542 /*
 543  * Delete Key.
 544  */
 545 void ath_key_delete(struct ath_common *common, struct ieee80211_key_conf *key)
 546 {
 547         ath_hw_keyreset(common, key->hw_key_idx);
 548         if (key->hw_key_idx < IEEE80211_WEP_NKID)
 549                 return;
 550
 551         clear_bit(key->hw_key_idx, common->keymap);
 552         if (key->cipher != WLAN_CIPHER_SUITE_TKIP)
 553                 return;
 554
 555         clear_bit(key->hw_key_idx + 64, common->keymap);
 556
 557         clear_bit(key->hw_key_idx, common->tkip_keymap);
 558         clear_bit(key->hw_key_idx + 64, common->tkip_keymap);
 559
 560         if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 561                 ath_hw_keyreset(common, key->hw_key_idx + 32);
 562                 clear_bit(key->hw_key_idx + 32, common->keymap);
 563                 clear_bit(key->hw_key_idx + 64 + 32, common->keymap);
 564
 565                 clear_bit(key->hw_key_idx + 32, common->tkip_keymap);
 566                 clear_bit(key->hw_key_idx + 64 + 32, common->tkip_keymap);
 567         }
 568 }
 569 EXPORT_SYMBOL(ath_key_delete);