drivers/net/wireless/ath/ath9k/common.c

   1 /*
   2  * Copyright (c) 2009 Atheros Communications Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 /*
  18  * Module for common driver code between ath9k and ath9k_htc
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23
  24 #include "common.h"
  25
  26 MODULE_AUTHOR("Atheros Communications");
  27 MODULE_DESCRIPTION("Shared library for Atheros wireless 802.11n LAN cards.");
  28 MODULE_LICENSE("Dual BSD/GPL");
  29
  30 int ath9k_cmn_padpos(__le16 frame_control)
  31 {
  32         int padpos = 24;
  33         if (ieee80211_has_a4(frame_control)) {
  34                 padpos += ETH_ALEN;
  35         }
  36         if (ieee80211_is_data_qos(frame_control)) {
  37                 padpos += IEEE80211_QOS_CTL_LEN;
  38         }
  39
  40         return padpos;
  41 }
  42 EXPORT_SYMBOL(ath9k_cmn_padpos);
  43
  44 int ath9k_cmn_get_hw_crypto_keytype(struct sk_buff *skb)
  45 {
  46         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
  47
  48         if (tx_info->control.hw_key) {
  49                 if (tx_info->control.hw_key->alg == ALG_WEP)
  50                         return ATH9K_KEY_TYPE_WEP;
  51                 else if (tx_info->control.hw_key->alg == ALG_TKIP)
  52                         return ATH9K_KEY_TYPE_TKIP;
  53                 else if (tx_info->control.hw_key->alg == ALG_CCMP)
  54                         return ATH9K_KEY_TYPE_AES;
  55         }
  56
  57         return ATH9K_KEY_TYPE_CLEAR;
  58 }
  59 EXPORT_SYMBOL(ath9k_cmn_get_hw_crypto_keytype);
  60
  61 static u32 ath9k_get_extchanmode(struct ieee80211_channel *chan,
  62                                  enum nl80211_channel_type channel_type)
  63 {
  64         u32 chanmode = 0;
  65
  66         switch (chan->band) {
  67         case IEEE80211_BAND_2GHZ:
  68                 switch (channel_type) {
  69                 case NL80211_CHAN_NO_HT:
  70                 case NL80211_CHAN_HT20:
  71                         chanmode = CHANNEL_G_HT20;
  72                         break;
  73                 case NL80211_CHAN_HT40PLUS:
  74                         chanmode = CHANNEL_G_HT40PLUS;
  75                         break;
  76                 case NL80211_CHAN_HT40MINUS:
  77                         chanmode = CHANNEL_G_HT40MINUS;
  78                         break;
  79                 }
  80                 break;
  81         case IEEE80211_BAND_5GHZ:
  82                 switch (channel_type) {
  83                 case NL80211_CHAN_NO_HT:
  84                 case NL80211_CHAN_HT20:
  85                         chanmode = CHANNEL_A_HT20;
  86                         break;
  87                 case NL80211_CHAN_HT40PLUS:
  88                         chanmode = CHANNEL_A_HT40PLUS;
  89                         break;
  90                 case NL80211_CHAN_HT40MINUS:
  91                         chanmode = CHANNEL_A_HT40MINUS;
  92                         break;
  93                 }
  94                 break;
  95         default:
  96                 break;
  97         }
  98
  99         return chanmode;
 100 }
 101
 102 /*
 103  * Update internal channel flags.
 104  */
 105 void ath9k_cmn_update_ichannel(struct ieee80211_hw *hw,
 106                                struct ath9k_channel *ichan)
 107 {
 108         struct ieee80211_channel *chan = hw->conf.channel;
 109         struct ieee80211_conf *conf = &hw->conf;
 110
 111         ichan->channel = chan->center_freq;
 112         ichan->chan = chan;
 113
 114         if (chan->band == IEEE80211_BAND_2GHZ) {
 115                 ichan->chanmode = CHANNEL_G;
 116                 ichan->channelFlags = CHANNEL_2GHZ | CHANNEL_OFDM | CHANNEL_G;
 117         } else {
 118                 ichan->chanmode = CHANNEL_A;
 119                 ichan->channelFlags = CHANNEL_5GHZ | CHANNEL_OFDM;
 120         }
 121
 122         if (conf_is_ht(conf))
 123                 ichan->chanmode = ath9k_get_extchanmode(chan,
 124                                                         conf->channel_type);
 125 }
 126 EXPORT_SYMBOL(ath9k_cmn_update_ichannel);
 127
 128 /*
 129  * Get the internal channel reference.
 130  */
 131 struct ath9k_channel *ath9k_cmn_get_curchannel(struct ieee80211_hw *hw,
 132                                                struct ath_hw *ah)
 133 {
 134         struct ieee80211_channel *curchan = hw->conf.channel;
 135         struct ath9k_channel *channel;
 136         u8 chan_idx;
 137
 138         chan_idx = curchan->hw_value;
 139         channel = &ah->channels[chan_idx];
 140         ath9k_cmn_update_ichannel(hw, channel);
 141
 142         return channel;
 143 }
 144 EXPORT_SYMBOL(ath9k_cmn_get_curchannel);
 145
 146 static int ath_setkey_tkip(struct ath_common *common, u16 keyix, const u8 *key,
 147                            struct ath9k_keyval *hk, const u8 *addr,
 148                            bool authenticator)
 149 {
 150         struct ath_hw *ah = common->ah;
 151         const u8 *key_rxmic;
 152         const u8 *key_txmic;
 153
 154         key_txmic = key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
 155         key_rxmic = key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
 156
 157         if (addr == NULL) {
 158                 /*
 159                  * Group key installation - only two key cache entries are used
 160                  * regardless of splitmic capability since group key is only
 161                  * used either for TX or RX.
 162                  */
 163                 if (authenticator) {
 164                         memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 165                         memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_mic));
 166                 } else {
 167                         memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 168                         memcpy(hk->kv_txmic, key_rxmic, sizeof(hk->kv_mic));
 169                 }
 170                 return ath9k_hw_set_keycache_entry(ah, keyix, hk, addr);
 171         }
 172         if (!common->splitmic) {
 173                 /* TX and RX keys share the same key cache entry. */
 174                 memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 175                 memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_txmic));
 176                 return ath9k_hw_set_keycache_entry(ah, keyix, hk, addr);
 177         }
 178
 179         /* Separate key cache entries for TX and RX */
 180
 181         /* TX key goes at first index, RX key at +32. */
 182         memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 183         if (!ath9k_hw_set_keycache_entry(ah, keyix, hk, NULL)) {
 184                 /* TX MIC entry failed. No need to proceed further */
 185                 ath_print(common, ATH_DBG_FATAL,
 186                           "Setting TX MIC Key Failed\n");
 187                 return 0;
 188         }
 189
 190         memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 191         /* XXX delete tx key on failure? */
 192         return ath9k_hw_set_keycache_entry(ah, keyix + 32, hk, addr);
 193 }
 194
 195 static int ath_reserve_key_cache_slot_tkip(struct ath_common *common)
 196 {
 197         int i;
 198
 199         for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 200                 if (test_bit(i, common->keymap) ||
 201                     test_bit(i + 64, common->keymap))
 202                         continue; /* At least one part of TKIP key allocated */
 203                 if (common->splitmic &&
 204                     (test_bit(i + 32, common->keymap) ||
 205                      test_bit(i + 64 + 32, common->keymap)))
 206                         continue; /* At least one part of TKIP key allocated */
 207
 208                 /* Found a free slot for a TKIP key */
 209                 return i;
 210         }
 211         return -1;
 212 }
 213
 214 static int ath_reserve_key_cache_slot(struct ath_common *common,
 215                                       enum ieee80211_key_alg alg)
 216 {
 217         int i;
 218
 219         if (alg == ALG_TKIP)
 220                 return ath_reserve_key_cache_slot_tkip(common);
 221
 222         /* First, try to find slots that would not be available for TKIP. */
 223         if (common->splitmic) {
 224                 for (i = IEEE80211_WEP_NKID; i < common->keymax / 4; i++) {
 225                         if (!test_bit(i, common->keymap) &&
 226                             (test_bit(i + 32, common->keymap) ||
 227                              test_bit(i + 64, common->keymap) ||
 228                              test_bit(i + 64 + 32, common->keymap)))
 229                                 return i;
 230                         if (!test_bit(i + 32, common->keymap) &&
 231                             (test_bit(i, common->keymap) ||
 232                              test_bit(i + 64, common->keymap) ||
 233                              test_bit(i + 64 + 32, common->keymap)))
 234                                 return i + 32;
 235                         if (!test_bit(i + 64, common->keymap) &&
 236                             (test_bit(i , common->keymap) ||
 237                              test_bit(i + 32, common->keymap) ||
 238                              test_bit(i + 64 + 32, common->keymap)))
 239                                 return i + 64;
 240                         if (!test_bit(i + 64 + 32, common->keymap) &&
 241                             (test_bit(i, common->keymap) ||
 242                              test_bit(i + 32, common->keymap) ||
 243                              test_bit(i + 64, common->keymap)))
 244                                 return i + 64 + 32;
 245                 }
 246         } else {
 247                 for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 248                         if (!test_bit(i, common->keymap) &&
 249                             test_bit(i + 64, common->keymap))
 250                                 return i;
 251                         if (test_bit(i, common->keymap) &&
 252                             !test_bit(i + 64, common->keymap))
 253                                 return i + 64;
 254                 }
 255         }
 256
 257         /* No partially used TKIP slots, pick any available slot */
 258         for (i = IEEE80211_WEP_NKID; i < common->keymax; i++) {
 259                 /* Do not allow slots that could be needed for TKIP group keys
 260                  * to be used. This limitation could be removed if we know that
 261                  * TKIP will not be used. */
 262                 if (i >= 64 && i < 64 + IEEE80211_WEP_NKID)
 263                         continue;
 264                 if (common->splitmic) {
 265                         if (i >= 32 && i < 32 + IEEE80211_WEP_NKID)
 266                                 continue;
 267                         if (i >= 64 + 32 && i < 64 + 32 + IEEE80211_WEP_NKID)
 268                                 continue;
 269                 }
 270
 271                 if (!test_bit(i, common->keymap))
 272                         return i; /* Found a free slot for a key */
 273         }
 274
 275         /* No free slot found */
 276         return -1;
 277 }
 278
 279 /*
 280  * Configure encryption in the HW.
 281  */
 282 int ath9k_cmn_key_config(struct ath_common *common,
 283                          struct ieee80211_vif *vif,
 284                          struct ieee80211_sta *sta,
 285                          struct ieee80211_key_conf *key)
 286 {
 287         struct ath_hw *ah = common->ah;
 288         struct ath9k_keyval hk;
 289         const u8 *mac = NULL;
 290         u8 gmac[ETH_ALEN];
 291         int ret = 0;
 292         int idx;
 293
 294         memset(&hk, 0, sizeof(hk));
 295
 296         switch (key->alg) {
 297         case ALG_WEP:
 298                 hk.kv_type = ATH9K_CIPHER_WEP;
 299                 break;
 300         case ALG_TKIP:
 301                 hk.kv_type = ATH9K_CIPHER_TKIP;
 302                 break;
 303         case ALG_CCMP:
 304                 hk.kv_type = ATH9K_CIPHER_AES_CCM;
 305                 break;
 306         default:
 307                 return -EOPNOTSUPP;
 308         }
 309
 310         hk.kv_len = key->keylen;
 311         memcpy(hk.kv_val, key->key, key->keylen);
 312
 313         if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
 314                 switch (vif->type) {
 315                 case NL80211_IFTYPE_AP:
 316                         memcpy(gmac, vif->addr, ETH_ALEN);
 317                         gmac[0] |= 0x01;
 318                         mac = gmac;
 319                         idx = ath_reserve_key_cache_slot(common, key->alg);
 320                         break;
 321                 case NL80211_IFTYPE_ADHOC:
 322                         if (!sta) {
 323                                 idx = key->keyidx;
 324                                 break;
 325                         }
 326                         memcpy(gmac, sta->addr, ETH_ALEN);
 327                         gmac[0] |= 0x01;
 328                         mac = gmac;
 329                         idx = ath_reserve_key_cache_slot(common, key->alg);
 330                         break;
 331                 default:
 332                         idx = key->keyidx;
 333                         break;
 334                 }
 335         } else if (key->keyidx) {
 336                 if (WARN_ON(!sta))
 337                         return -EOPNOTSUPP;
 338                 mac = sta->addr;
 339
 340                 if (vif->type != NL80211_IFTYPE_AP) {
 341                         /* Only keyidx 0 should be used with unicast key, but
 342                          * allow this for client mode for now. */
 343                         idx = key->keyidx;
 344                 } else
 345                         return -EIO;
 346         } else {
 347                 if (WARN_ON(!sta))
 348                         return -EOPNOTSUPP;
 349                 mac = sta->addr;
 350
 351                 idx = ath_reserve_key_cache_slot(common, key->alg);
 352         }
 353
 354         if (idx < 0)
 355                 return -ENOSPC; /* no free key cache entries */
 356
 357         if (key->alg == ALG_TKIP)
 358                 ret = ath_setkey_tkip(common, idx, key->key, &hk, mac,
 359                                       vif->type == NL80211_IFTYPE_AP);
 360         else
 361                 ret = ath9k_hw_set_keycache_entry(ah, idx, &hk, mac);
 362
 363         if (!ret)
 364                 return -EIO;
 365
 366         set_bit(idx, common->keymap);
 367         if (key->alg == ALG_TKIP) {
 368                 set_bit(idx + 64, common->keymap);
 369                 set_bit(idx, common->tkip_keymap);
 370                 set_bit(idx + 64, common->tkip_keymap);
 371                 if (common->splitmic) {
 372                         set_bit(idx + 32, common->keymap);
 373                         set_bit(idx + 64 + 32, common->keymap);
 374                         set_bit(idx + 32, common->tkip_keymap);
 375                         set_bit(idx + 64 + 32, common->tkip_keymap);
 376                 }
 377         }
 378
 379         return idx;
 380 }
 381 EXPORT_SYMBOL(ath9k_cmn_key_config);
 382
 383 /*
 384  * Delete Key.
 385  */
 386 void ath9k_cmn_key_delete(struct ath_common *common,
 387                           struct ieee80211_key_conf *key)
 388 {
 389         struct ath_hw *ah = common->ah;
 390
 391         ath9k_hw_keyreset(ah, key->hw_key_idx);
 392         if (key->hw_key_idx < IEEE80211_WEP_NKID)
 393                 return;
 394
 395         clear_bit(key->hw_key_idx, common->keymap);
 396         if (key->alg != ALG_TKIP)
 397                 return;
 398
 399         clear_bit(key->hw_key_idx + 64, common->keymap);
 400
 401         clear_bit(key->hw_key_idx, common->tkip_keymap);
 402         clear_bit(key->hw_key_idx + 64, common->tkip_keymap);
 403
 404         if (common->splitmic) {
 405                 ath9k_hw_keyreset(ah, key->hw_key_idx + 32);
 406                 clear_bit(key->hw_key_idx + 32, common->keymap);
 407                 clear_bit(key->hw_key_idx + 64 + 32, common->keymap);
 408
 409                 clear_bit(key->hw_key_idx + 32, common->tkip_keymap);
 410                 clear_bit(key->hw_key_idx + 64 + 32, common->tkip_keymap);
 411         }
 412 }
 413 EXPORT_SYMBOL(ath9k_cmn_key_delete);
 414
 415 int ath9k_cmn_count_streams(unsigned int chainmask, int max)
 416 {
 417         int streams = 0;
 418
 419         do {
 420                 if (++streams == max)
 421                         break;
 422         } while ((chainmask = chainmask & (chainmask - 1)));
 423
 424         return streams;
 425 }
 426 EXPORT_SYMBOL(ath9k_cmn_count_streams);
 427
 428 static int __init ath9k_cmn_init(void)
 429 {
 430         return 0;
 431 }
 432 module_init(ath9k_cmn_init);
 433
 434 static void __exit ath9k_cmn_exit(void)
 435 {
 436         return;
 437 }
 438 module_exit(ath9k_cmn_exit);