drivers/net/wireless/ath/key.c - kernel/panda - Git at Google

 /*
  * Copyright (c) 2009 Atheros Communications Inc.
  * Copyright (c) 2010 Bruno Randolf <br1@einfach.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #include <linux/export.h>
 #include <asm/unaligned.h>
 #include <net/mac80211.h>

 #include "ath.h"
 #include "reg.h"

 #define REG_READ			(common->ops->read)
 #define REG_WRITE(_ah, _reg, _val)	(common->ops->write)(_ah, _val, _reg)
 #define ENABLE_REGWRITE_BUFFER(_ah)			\
 	if (common->ops->enable_write_buffer)		\
 		common->ops->enable_write_buffer((_ah));

 #define REGWRITE_BUFFER_FLUSH(_ah)			\
 	if (common->ops->write_flush)			\
 		common->ops->write_flush((_ah));


 #define IEEE80211_WEP_NKID      4       /* number of key ids */

 /************************/
 /* Key Cache Management */
 /************************/

 bool ath_hw_keyreset(struct ath_common *common, u16 entry)
 {
 	u32 keyType;
 	void *ah = common->ah;

 	if (entry >= common->keymax) {
 		ath_err(common, "keycache entry %u out of range\n", entry);
 		return false;
 	}

 	keyType = REG_READ(ah, AR_KEYTABLE_TYPE(entry));

 	ENABLE_REGWRITE_BUFFER(ah);

 	REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
 	REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
 	REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);

 	if (keyType == AR_KEYTABLE_TYPE_TKIP) {
 		u16 micentry = entry + 64;

 		REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
 		if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
 			REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0);
 			REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
 				  AR_KEYTABLE_TYPE_CLR);
 		}

 	}

 	REGWRITE_BUFFER_FLUSH(ah);

 	return true;
 }
 EXPORT_SYMBOL(ath_hw_keyreset);

 static bool ath_hw_keysetmac(struct ath_common *common,
 			     u16 entry, const u8 *mac)
 {
 	u32 macHi, macLo;
 	u32 unicast_flag = AR_KEYTABLE_VALID;
 	void *ah = common->ah;

 	if (entry >= common->keymax) {
 		ath_err(common, "keycache entry %u out of range\n", entry);
 		return false;
 	}

 	if (mac != NULL) {
 		/*
 		 * AR_KEYTABLE_VALID indicates that the address is a unicast
 		 * address, which must match the transmitter address for
 		 * decrypting frames.
 		 * Not setting this bit allows the hardware to use the key
 		 * for multicast frame decryption.
 		 */
 		if (mac[0] & 0x01)
 			unicast_flag = 0;

 		macLo = get_unaligned_le32(mac);
 		macHi = get_unaligned_le16(mac + 4);
 		macLo >>= 1;
 		macLo |= (macHi & 1) << 31;
 		macHi >>= 1;
 	} else {
 		macLo = macHi = 0;
 	}
 	ENABLE_REGWRITE_BUFFER(ah);

 	REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
 	REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);

 	REGWRITE_BUFFER_FLUSH(ah);

 	return true;
 }

 static bool ath_hw_set_keycache_entry(struct ath_common *common, u16 entry,
 				      const struct ath_keyval *k,
 				      const u8 *mac)
 {
 	void *ah = common->ah;
 	u32 key0, key1, key2, key3, key4;
 	u32 keyType;

 	if (entry >= common->keymax) {
 		ath_err(common, "keycache entry %u out of range\n", entry);
 		return false;
 	}

 	switch (k->kv_type) {
 	case ATH_CIPHER_AES_OCB:
 		keyType = AR_KEYTABLE_TYPE_AES;
 		break;
 	case ATH_CIPHER_AES_CCM:
 		if (!(common->crypt_caps & ATH_CRYPT_CAP_CIPHER_AESCCM)) {
 			ath_dbg(common, ATH_DBG_ANY,
 				"AES-CCM not supported by this mac rev\n");
 			return false;
 		}
 		keyType = AR_KEYTABLE_TYPE_CCM;
 		break;
 	case ATH_CIPHER_TKIP:
 		keyType = AR_KEYTABLE_TYPE_TKIP;
 		if (entry + 64 >= common->keymax) {
 			ath_dbg(common, ATH_DBG_ANY,
 				"entry %u inappropriate for TKIP\n", entry);
 			return false;
 		}
 		break;
 	case ATH_CIPHER_WEP:
 		if (k->kv_len < WLAN_KEY_LEN_WEP40) {
 			ath_dbg(common, ATH_DBG_ANY,
 				"WEP key length %u too small\n", k->kv_len);
 			return false;
 		}
 		if (k->kv_len <= WLAN_KEY_LEN_WEP40)
 			keyType = AR_KEYTABLE_TYPE_40;
 		else if (k->kv_len <= WLAN_KEY_LEN_WEP104)
 			keyType = AR_KEYTABLE_TYPE_104;
 		else
 			keyType = AR_KEYTABLE_TYPE_128;
 		break;
 	case ATH_CIPHER_CLR:
 		keyType = AR_KEYTABLE_TYPE_CLR;
 		break;
 	default:
 		ath_err(common, "cipher %u not supported\n", k->kv_type);
 		return false;
 	}

 	key0 = get_unaligned_le32(k->kv_val + 0);
 	key1 = get_unaligned_le16(k->kv_val + 4);
 	key2 = get_unaligned_le32(k->kv_val + 6);
 	key3 = get_unaligned_le16(k->kv_val + 10);
 	key4 = get_unaligned_le32(k->kv_val + 12);
 	if (k->kv_len <= WLAN_KEY_LEN_WEP104)
 		key4 &= 0xff;

 	/*
 	 * Note: Key cache registers access special memory area that requires
 	 * two 32-bit writes to actually update the values in the internal
 	 * memory. Consequently, the exact order and pairs used here must be
 	 * maintained.
 	 */

 	if (keyType == AR_KEYTABLE_TYPE_TKIP) {
 		u16 micentry = entry + 64;

 		/*
 		 * Write inverted key[47:0] first to avoid Michael MIC errors
 		 * on frames that could be sent or received at the same time.
 		 * The correct key will be written in the end once everything
 		 * else is ready.
 		 */
 		REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);

 		/* Write key[95:48] */
 		REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
 		REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);

 		/* Write key[127:96] and key type */
 		REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
 		REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);

 		/* Write MAC address for the entry */
 		(void) ath_hw_keysetmac(common, entry, mac);

 		if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
 			/*
 			 * TKIP uses two key cache entries:
 			 * Michael MIC TX/RX keys in the same key cache entry
 			 * (idx = main index + 64):
 			 * key0 [31:0] = RX key [31:0]
 			 * key1 [15:0] = TX key [31:16]
 			 * key1 [31:16] = reserved
 			 * key2 [31:0] = RX key [63:32]
 			 * key3 [15:0] = TX key [15:0]
 			 * key3 [31:16] = reserved
 			 * key4 [31:0] = TX key [63:32]
 			 */
 			u32 mic0, mic1, mic2, mic3, mic4;

 			mic0 = get_unaligned_le32(k->kv_mic + 0);
 			mic2 = get_unaligned_le32(k->kv_mic + 4);
 			mic1 = get_unaligned_le16(k->kv_txmic + 2) & 0xffff;
 			mic3 = get_unaligned_le16(k->kv_txmic + 0) & 0xffff;
 			mic4 = get_unaligned_le32(k->kv_txmic + 4);

 			ENABLE_REGWRITE_BUFFER(ah);

 			/* Write RX[31:0] and TX[31:16] */
 			REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
 			REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);

 			/* Write RX[63:32] and TX[15:0] */
 			REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
 			REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);

 			/* Write TX[63:32] and keyType(reserved) */
 			REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
 			REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
 				  AR_KEYTABLE_TYPE_CLR);

 			REGWRITE_BUFFER_FLUSH(ah);

 		} else {
 			/*
 			 * TKIP uses four key cache entries (two for group
 			 * keys):
 			 * Michael MIC TX/RX keys are in different key cache
 			 * entries (idx = main index + 64 for TX and
 			 * main index + 32 + 96 for RX):
 			 * key0 [31:0] = TX/RX MIC key [31:0]
 			 * key1 [31:0] = reserved
 			 * key2 [31:0] = TX/RX MIC key [63:32]
 			 * key3 [31:0] = reserved
 			 * key4 [31:0] = reserved
 			 *
 			 * Upper layer code will call this function separately
 			 * for TX and RX keys when these registers offsets are
 			 * used.
 			 */
 			u32 mic0, mic2;

 			mic0 = get_unaligned_le32(k->kv_mic + 0);
 			mic2 = get_unaligned_le32(k->kv_mic + 4);

 			ENABLE_REGWRITE_BUFFER(ah);

 			/* Write MIC key[31:0] */
 			REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
 			REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);

 			/* Write MIC key[63:32] */
 			REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
 			REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);

 			/* Write TX[63:32] and keyType(reserved) */
 			REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0);
 			REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
 				  AR_KEYTABLE_TYPE_CLR);

 			REGWRITE_BUFFER_FLUSH(ah);
 		}

 		ENABLE_REGWRITE_BUFFER(ah);

 		/* MAC address registers are reserved for the MIC entry */
 		REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
 		REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);

 		/*
 		 * Write the correct (un-inverted) key[47:0] last to enable
 		 * TKIP now that all other registers are set with correct
 		 * values.
 		 */
 		REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);

 		REGWRITE_BUFFER_FLUSH(ah);
 	} else {
 		ENABLE_REGWRITE_BUFFER(ah);

 		/* Write key[47:0] */
 		REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
 		REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);

 		/* Write key[95:48] */
 		REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
 		REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);

 		/* Write key[127:96] and key type */
 		REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
 		REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);

 		REGWRITE_BUFFER_FLUSH(ah);

 		/* Write MAC address for the entry */
 		(void) ath_hw_keysetmac(common, entry, mac);
 	}

 	return true;
 }

 static int ath_setkey_tkip(struct ath_common *common, u16 keyix, const u8 *key,
 			   struct ath_keyval *hk, const u8 *addr,
 			   bool authenticator)
 {
 	const u8 *key_rxmic;
 	const u8 *key_txmic;

 	key_txmic = key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
 	key_rxmic = key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;

 	if (addr == NULL) {
 		/*
 		 * Group key installation - only two key cache entries are used
 		 * regardless of splitmic capability since group key is only
 		 * used either for TX or RX.
 		 */
 		if (authenticator) {
 			memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 			memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_mic));
 		} else {
 			memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 			memcpy(hk->kv_txmic, key_rxmic, sizeof(hk->kv_mic));
 		}
 		return ath_hw_set_keycache_entry(common, keyix, hk, addr);
 	}
 	if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
 		/* TX and RX keys share the same key cache entry. */
 		memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 		memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_txmic));
 		return ath_hw_set_keycache_entry(common, keyix, hk, addr);
 	}

 	/* Separate key cache entries for TX and RX */

 	/* TX key goes at first index, RX key at +32. */
 	memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
 	if (!ath_hw_set_keycache_entry(common, keyix, hk, NULL)) {
 		/* TX MIC entry failed. No need to proceed further */
 		ath_err(common, "Setting TX MIC Key Failed\n");
 		return 0;
 	}

 	memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
 	/* XXX delete tx key on failure? */
 	return ath_hw_set_keycache_entry(common, keyix + 32, hk, addr);
 }

 static int ath_reserve_key_cache_slot_tkip(struct ath_common *common)
 {
 	int i;

 	for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 		if (test_bit(i, common->keymap) ||
 		    test_bit(i + 64, common->keymap))
 			continue; /* At least one part of TKIP key allocated */
 		if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) &&
 		    (test_bit(i + 32, common->keymap) ||
 		     test_bit(i + 64 + 32, common->keymap)))
 			continue; /* At least one part of TKIP key allocated */

 		/* Found a free slot for a TKIP key */
 		return i;
 	}
 	return -1;
 }

 static int ath_reserve_key_cache_slot(struct ath_common *common,
 				      u32 cipher)
 {
 	int i;

 	if (cipher == WLAN_CIPHER_SUITE_TKIP)
 		return ath_reserve_key_cache_slot_tkip(common);

 	/* First, try to find slots that would not be available for TKIP. */
 	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 		for (i = IEEE80211_WEP_NKID; i < common->keymax / 4; i++) {
 			if (!test_bit(i, common->keymap) &&
 			    (test_bit(i + 32, common->keymap) ||
 			     test_bit(i + 64, common->keymap) ||
 			     test_bit(i + 64 + 32, common->keymap)))
 				return i;
 			if (!test_bit(i + 32, common->keymap) &&
 			    (test_bit(i, common->keymap) ||
 			     test_bit(i + 64, common->keymap) ||
 			     test_bit(i + 64 + 32, common->keymap)))
 				return i + 32;
 			if (!test_bit(i + 64, common->keymap) &&
 			    (test_bit(i , common->keymap) ||
 			     test_bit(i + 32, common->keymap) ||
 			     test_bit(i + 64 + 32, common->keymap)))
 				return i + 64;
 			if (!test_bit(i + 64 + 32, common->keymap) &&
 			    (test_bit(i, common->keymap) ||
 			     test_bit(i + 32, common->keymap) ||
 			     test_bit(i + 64, common->keymap)))
 				return i + 64 + 32;
 		}
 	} else {
 		for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
 			if (!test_bit(i, common->keymap) &&
 			    test_bit(i + 64, common->keymap))
 				return i;
 			if (test_bit(i, common->keymap) &&
 			    !test_bit(i + 64, common->keymap))
 				return i + 64;
 		}
 	}

 	/* No partially used TKIP slots, pick any available slot */
 	for (i = IEEE80211_WEP_NKID; i < common->keymax; i++) {
 		/* Do not allow slots that could be needed for TKIP group keys
 		 * to be used. This limitation could be removed if we know that
 		 * TKIP will not be used. */
 		if (i >= 64 && i < 64 + IEEE80211_WEP_NKID)
 			continue;
 		if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 			if (i >= 32 && i < 32 + IEEE80211_WEP_NKID)
 				continue;
 			if (i >= 64 + 32 && i < 64 + 32 + IEEE80211_WEP_NKID)
 				continue;
 		}

 		if (!test_bit(i, common->keymap))
 			return i; /* Found a free slot for a key */
 	}

 	/* No free slot found */
 	return -1;
 }

 /*
  * Configure encryption in the HW.
  */
 int ath_key_config(struct ath_common *common,
 			  struct ieee80211_vif *vif,
 			  struct ieee80211_sta *sta,
 			  struct ieee80211_key_conf *key)
 {
 	struct ath_keyval hk;
 	const u8 *mac = NULL;
 	u8 gmac[ETH_ALEN];
 	int ret = 0;
 	int idx;

 	memset(&hk, 0, sizeof(hk));

 	switch (key->cipher) {
 	case 0:
 		hk.kv_type = ATH_CIPHER_CLR;
 		break;
 	case WLAN_CIPHER_SUITE_WEP40:
 	case WLAN_CIPHER_SUITE_WEP104:
 		hk.kv_type = ATH_CIPHER_WEP;
 		break;
 	case WLAN_CIPHER_SUITE_TKIP:
 		hk.kv_type = ATH_CIPHER_TKIP;
 		break;
 	case WLAN_CIPHER_SUITE_CCMP:
 		hk.kv_type = ATH_CIPHER_AES_CCM;
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}

 	hk.kv_len = key->keylen;
 	if (key->keylen)
 		memcpy(hk.kv_val, key->key, key->keylen);

 	if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
 		switch (vif->type) {
 		case NL80211_IFTYPE_AP:
 			memcpy(gmac, vif->addr, ETH_ALEN);
 			gmac[0] |= 0x01;
 			mac = gmac;
 			idx = ath_reserve_key_cache_slot(common, key->cipher);
 			break;
 		case NL80211_IFTYPE_ADHOC:
 			if (!sta) {
 				idx = key->keyidx;
 				break;
 			}
 			memcpy(gmac, sta->addr, ETH_ALEN);
 			gmac[0] |= 0x01;
 			mac = gmac;
 			idx = ath_reserve_key_cache_slot(common, key->cipher);
 			break;
 		default:
 			idx = key->keyidx;
 			break;
 		}
 	} else if (key->keyidx) {
 		if (WARN_ON(!sta))
 			return -EOPNOTSUPP;
 		mac = sta->addr;

 		if (vif->type != NL80211_IFTYPE_AP) {
 			/* Only keyidx 0 should be used with unicast key, but
 			 * allow this for client mode for now. */
 			idx = key->keyidx;
 		} else
 			return -EIO;
 	} else {
 		if (WARN_ON(!sta))
 			return -EOPNOTSUPP;
 		mac = sta->addr;

 		idx = ath_reserve_key_cache_slot(common, key->cipher);
 	}

 	if (idx < 0)
 		return -ENOSPC; /* no free key cache entries */

 	if (key->cipher == WLAN_CIPHER_SUITE_TKIP)
 		ret = ath_setkey_tkip(common, idx, key->key, &hk, mac,
 				      vif->type == NL80211_IFTYPE_AP);
 	else
 		ret = ath_hw_set_keycache_entry(common, idx, &hk, mac);

 	if (!ret)
 		return -EIO;

 	set_bit(idx, common->keymap);
 	if (key->cipher == WLAN_CIPHER_SUITE_TKIP) {
 		set_bit(idx + 64, common->keymap);
 		set_bit(idx, common->tkip_keymap);
 		set_bit(idx + 64, common->tkip_keymap);
 		if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 			set_bit(idx + 32, common->keymap);
 			set_bit(idx + 64 + 32, common->keymap);
 			set_bit(idx + 32, common->tkip_keymap);
 			set_bit(idx + 64 + 32, common->tkip_keymap);
 		}
 	}

 	return idx;
 }
 EXPORT_SYMBOL(ath_key_config);

 /*
  * Delete Key.
  */
 void ath_key_delete(struct ath_common *common, struct ieee80211_key_conf *key)
 {
 	ath_hw_keyreset(common, key->hw_key_idx);
 	if (key->hw_key_idx < IEEE80211_WEP_NKID)
 		return;

 	clear_bit(key->hw_key_idx, common->keymap);
 	if (key->cipher != WLAN_CIPHER_SUITE_TKIP)
 		return;

 	clear_bit(key->hw_key_idx + 64, common->keymap);

 	clear_bit(key->hw_key_idx, common->tkip_keymap);
 	clear_bit(key->hw_key_idx + 64, common->tkip_keymap);

 	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
 		ath_hw_keyreset(common, key->hw_key_idx + 32);
 		clear_bit(key->hw_key_idx + 32, common->keymap);
 		clear_bit(key->hw_key_idx + 64 + 32, common->keymap);

 		clear_bit(key->hw_key_idx + 32, common->tkip_keymap);
 		clear_bit(key->hw_key_idx + 64 + 32, common->tkip_keymap);
 	}
 }
 EXPORT_SYMBOL(ath_key_delete);
	/*
	* Copyright (c) 2009 Atheros Communications Inc.
	* Copyright (c) 2010 Bruno Randolf <br1@einfach.org>
	*
	* Permission to use, copy, modify, and/or distribute this software for any
	* purpose with or without fee is hereby granted, provided that the above
	* copyright notice and this permission notice appear in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#include <linux/export.h>
	#include <asm/unaligned.h>
	#include <net/mac80211.h>

	#include "ath.h"
	#include "reg.h"

	#define REG_READ (common->ops->read)
	#define REG_WRITE(_ah, _reg, _val) (common->ops->write)(_ah, _val, _reg)
	#define ENABLE_REGWRITE_BUFFER(_ah) \
	if (common->ops->enable_write_buffer) \
	common->ops->enable_write_buffer((_ah));

	#define REGWRITE_BUFFER_FLUSH(_ah) \
	if (common->ops->write_flush) \
	common->ops->write_flush((_ah));


	#define IEEE80211_WEP_NKID 4 /* number of key ids */

	/************************/
	/* Key Cache Management */
	/************************/

	bool ath_hw_keyreset(struct ath_common *common, u16 entry)
	{
	u32 keyType;
	void *ah = common->ah;

	if (entry >= common->keymax) {
	ath_err(common, "keycache entry %u out of range\n", entry);
	return false;
	}

	keyType = REG_READ(ah, AR_KEYTABLE_TYPE(entry));

	ENABLE_REGWRITE_BUFFER(ah);

	REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
	REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
	REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);

	if (keyType == AR_KEYTABLE_TYPE_TKIP) {
	u16 micentry = entry + 64;

	REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
	if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
	REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
	AR_KEYTABLE_TYPE_CLR);
	}

	}

	REGWRITE_BUFFER_FLUSH(ah);

	return true;
	}
	EXPORT_SYMBOL(ath_hw_keyreset);

	static bool ath_hw_keysetmac(struct ath_common *common,
	u16 entry, const u8 *mac)
	{
	u32 macHi, macLo;
	u32 unicast_flag = AR_KEYTABLE_VALID;
	void *ah = common->ah;

	if (entry >= common->keymax) {
	ath_err(common, "keycache entry %u out of range\n", entry);
	return false;
	}

	if (mac != NULL) {
	/*
	* AR_KEYTABLE_VALID indicates that the address is a unicast
	* address, which must match the transmitter address for
	* decrypting frames.
	* Not setting this bit allows the hardware to use the key
	* for multicast frame decryption.
	*/
	if (mac[0] & 0x01)
	unicast_flag = 0;

	macLo = get_unaligned_le32(mac);
	macHi = get_unaligned_le16(mac + 4);
	macLo >>= 1;
	macLo \|= (macHi & 1) << 31;
	macHi >>= 1;
	} else {
	macLo = macHi = 0;
	}
	ENABLE_REGWRITE_BUFFER(ah);

	REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
	REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi \| unicast_flag);

	REGWRITE_BUFFER_FLUSH(ah);

	return true;
	}

	static bool ath_hw_set_keycache_entry(struct ath_common *common, u16 entry,
	const struct ath_keyval *k,
	const u8 *mac)
	{
	void *ah = common->ah;
	u32 key0, key1, key2, key3, key4;
	u32 keyType;

	if (entry >= common->keymax) {
	ath_err(common, "keycache entry %u out of range\n", entry);
	return false;
	}

	switch (k->kv_type) {
	case ATH_CIPHER_AES_OCB:
	keyType = AR_KEYTABLE_TYPE_AES;
	break;
	case ATH_CIPHER_AES_CCM:
	if (!(common->crypt_caps & ATH_CRYPT_CAP_CIPHER_AESCCM)) {
	ath_dbg(common, ATH_DBG_ANY,
	"AES-CCM not supported by this mac rev\n");
	return false;
	}
	keyType = AR_KEYTABLE_TYPE_CCM;
	break;
	case ATH_CIPHER_TKIP:
	keyType = AR_KEYTABLE_TYPE_TKIP;
	if (entry + 64 >= common->keymax) {
	ath_dbg(common, ATH_DBG_ANY,
	"entry %u inappropriate for TKIP\n", entry);
	return false;
	}
	break;
	case ATH_CIPHER_WEP:
	if (k->kv_len < WLAN_KEY_LEN_WEP40) {
	ath_dbg(common, ATH_DBG_ANY,
	"WEP key length %u too small\n", k->kv_len);
	return false;
	}
	if (k->kv_len <= WLAN_KEY_LEN_WEP40)
	keyType = AR_KEYTABLE_TYPE_40;
	else if (k->kv_len <= WLAN_KEY_LEN_WEP104)
	keyType = AR_KEYTABLE_TYPE_104;
	else
	keyType = AR_KEYTABLE_TYPE_128;
	break;
	case ATH_CIPHER_CLR:
	keyType = AR_KEYTABLE_TYPE_CLR;
	break;
	default:
	ath_err(common, "cipher %u not supported\n", k->kv_type);
	return false;
	}

	key0 = get_unaligned_le32(k->kv_val + 0);
	key1 = get_unaligned_le16(k->kv_val + 4);
	key2 = get_unaligned_le32(k->kv_val + 6);
	key3 = get_unaligned_le16(k->kv_val + 10);
	key4 = get_unaligned_le32(k->kv_val + 12);
	if (k->kv_len <= WLAN_KEY_LEN_WEP104)
	key4 &= 0xff;

	/*
	* Note: Key cache registers access special memory area that requires
	* two 32-bit writes to actually update the values in the internal
	* memory. Consequently, the exact order and pairs used here must be
	* maintained.
	*/

	if (keyType == AR_KEYTABLE_TYPE_TKIP) {
	u16 micentry = entry + 64;

	/*
	* Write inverted key[47:0] first to avoid Michael MIC errors
	* on frames that could be sent or received at the same time.
	* The correct key will be written in the end once everything
	* else is ready.
	*/
	REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);

	/* Write key[95:48] */
	REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);

	/* Write key[127:96] and key type */
	REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);

	/* Write MAC address for the entry */
	(void) ath_hw_keysetmac(common, entry, mac);

	if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
	/*
	* TKIP uses two key cache entries:
	* Michael MIC TX/RX keys in the same key cache entry
	* (idx = main index + 64):
	* key0 [31:0] = RX key [31:0]
	* key1 [15:0] = TX key [31:16]
	* key1 [31:16] = reserved
	* key2 [31:0] = RX key [63:32]
	* key3 [15:0] = TX key [15:0]
	* key3 [31:16] = reserved
	* key4 [31:0] = TX key [63:32]
	*/
	u32 mic0, mic1, mic2, mic3, mic4;

	mic0 = get_unaligned_le32(k->kv_mic + 0);
	mic2 = get_unaligned_le32(k->kv_mic + 4);
	mic1 = get_unaligned_le16(k->kv_txmic + 2) & 0xffff;
	mic3 = get_unaligned_le16(k->kv_txmic + 0) & 0xffff;
	mic4 = get_unaligned_le32(k->kv_txmic + 4);

	ENABLE_REGWRITE_BUFFER(ah);

	/* Write RX[31:0] and TX[31:16] */
	REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);

	/* Write RX[63:32] and TX[15:0] */
	REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);

	/* Write TX[63:32] and keyType(reserved) */
	REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
	AR_KEYTABLE_TYPE_CLR);

	REGWRITE_BUFFER_FLUSH(ah);

	} else {
	/*
	* TKIP uses four key cache entries (two for group
	* keys):
	* Michael MIC TX/RX keys are in different key cache
	* entries (idx = main index + 64 for TX and
	* main index + 32 + 96 for RX):
	* key0 [31:0] = TX/RX MIC key [31:0]
	* key1 [31:0] = reserved
	* key2 [31:0] = TX/RX MIC key [63:32]
	* key3 [31:0] = reserved
	* key4 [31:0] = reserved
	*
	* Upper layer code will call this function separately
	* for TX and RX keys when these registers offsets are
	* used.
	*/
	u32 mic0, mic2;

	mic0 = get_unaligned_le32(k->kv_mic + 0);
	mic2 = get_unaligned_le32(k->kv_mic + 4);

	ENABLE_REGWRITE_BUFFER(ah);

	/* Write MIC key[31:0] */
	REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);

	/* Write MIC key[63:32] */
	REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);

	/* Write TX[63:32] and keyType(reserved) */
	REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
	AR_KEYTABLE_TYPE_CLR);

	REGWRITE_BUFFER_FLUSH(ah);
	}

	ENABLE_REGWRITE_BUFFER(ah);

	/* MAC address registers are reserved for the MIC entry */
	REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
	REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);

	/*
	* Write the correct (un-inverted) key[47:0] last to enable
	* TKIP now that all other registers are set with correct
	* values.
	*/
	REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);

	REGWRITE_BUFFER_FLUSH(ah);
	} else {
	ENABLE_REGWRITE_BUFFER(ah);

	/* Write key[47:0] */
	REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
	REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);

	/* Write key[95:48] */
	REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
	REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);

	/* Write key[127:96] and key type */
	REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
	REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);

	REGWRITE_BUFFER_FLUSH(ah);

	/* Write MAC address for the entry */
	(void) ath_hw_keysetmac(common, entry, mac);
	}

	return true;
	}

	static int ath_setkey_tkip(struct ath_common common, u16 keyix, const u8 key,
	struct ath_keyval hk, const u8 addr,
	bool authenticator)
	{
	const u8 *key_rxmic;
	const u8 *key_txmic;

	key_txmic = key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
	key_rxmic = key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;

	if (addr == NULL) {
	/*
	* Group key installation - only two key cache entries are used
	* regardless of splitmic capability since group key is only
	* used either for TX or RX.
	*/
	if (authenticator) {
	memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
	memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_mic));
	} else {
	memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
	memcpy(hk->kv_txmic, key_rxmic, sizeof(hk->kv_mic));
	}
	return ath_hw_set_keycache_entry(common, keyix, hk, addr);
	}
	if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) {
	/* TX and RX keys share the same key cache entry. */
	memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
	memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_txmic));
	return ath_hw_set_keycache_entry(common, keyix, hk, addr);
	}

	/* Separate key cache entries for TX and RX */

	/* TX key goes at first index, RX key at +32. */
	memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic));
	if (!ath_hw_set_keycache_entry(common, keyix, hk, NULL)) {
	/* TX MIC entry failed. No need to proceed further */
	ath_err(common, "Setting TX MIC Key Failed\n");
	return 0;
	}

	memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic));
	/* XXX delete tx key on failure? */
	return ath_hw_set_keycache_entry(common, keyix + 32, hk, addr);
	}

	static int ath_reserve_key_cache_slot_tkip(struct ath_common *common)
	{
	int i;

	for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
	if (test_bit(i, common->keymap) \|\|
	test_bit(i + 64, common->keymap))
	continue; /* At least one part of TKIP key allocated */
	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) &&
	(test_bit(i + 32, common->keymap) \|\|
	test_bit(i + 64 + 32, common->keymap)))
	continue; /* At least one part of TKIP key allocated */

	/* Found a free slot for a TKIP key */
	return i;
	}
	return -1;
	}

	static int ath_reserve_key_cache_slot(struct ath_common *common,
	u32 cipher)
	{
	int i;

	if (cipher == WLAN_CIPHER_SUITE_TKIP)
	return ath_reserve_key_cache_slot_tkip(common);

	/* First, try to find slots that would not be available for TKIP. */
	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
	for (i = IEEE80211_WEP_NKID; i < common->keymax / 4; i++) {
	if (!test_bit(i, common->keymap) &&
	(test_bit(i + 32, common->keymap) \|\|
	test_bit(i + 64, common->keymap) \|\|
	test_bit(i + 64 + 32, common->keymap)))
	return i;
	if (!test_bit(i + 32, common->keymap) &&
	(test_bit(i, common->keymap) \|\|
	test_bit(i + 64, common->keymap) \|\|
	test_bit(i + 64 + 32, common->keymap)))
	return i + 32;
	if (!test_bit(i + 64, common->keymap) &&
	(test_bit(i , common->keymap) \|\|
	test_bit(i + 32, common->keymap) \|\|
	test_bit(i + 64 + 32, common->keymap)))
	return i + 64;
	if (!test_bit(i + 64 + 32, common->keymap) &&
	(test_bit(i, common->keymap) \|\|
	test_bit(i + 32, common->keymap) \|\|
	test_bit(i + 64, common->keymap)))
	return i + 64 + 32;
	}
	} else {
	for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) {
	if (!test_bit(i, common->keymap) &&
	test_bit(i + 64, common->keymap))
	return i;
	if (test_bit(i, common->keymap) &&
	!test_bit(i + 64, common->keymap))
	return i + 64;
	}
	}

	/* No partially used TKIP slots, pick any available slot */
	for (i = IEEE80211_WEP_NKID; i < common->keymax; i++) {
	/* Do not allow slots that could be needed for TKIP group keys
	* to be used. This limitation could be removed if we know that
	* TKIP will not be used. */
	if (i >= 64 && i < 64 + IEEE80211_WEP_NKID)
	continue;
	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
	if (i >= 32 && i < 32 + IEEE80211_WEP_NKID)
	continue;
	if (i >= 64 + 32 && i < 64 + 32 + IEEE80211_WEP_NKID)
	continue;
	}

	if (!test_bit(i, common->keymap))
	return i; /* Found a free slot for a key */
	}

	/* No free slot found */
	return -1;
	}

	/*
	* Configure encryption in the HW.
	*/
	int ath_key_config(struct ath_common *common,
	struct ieee80211_vif *vif,
	struct ieee80211_sta *sta,
	struct ieee80211_key_conf *key)
	{
	struct ath_keyval hk;
	const u8 *mac = NULL;
	u8 gmac[ETH_ALEN];
	int ret = 0;
	int idx;

	memset(&hk, 0, sizeof(hk));

	switch (key->cipher) {
	case 0:
	hk.kv_type = ATH_CIPHER_CLR;
	break;
	case WLAN_CIPHER_SUITE_WEP40:
	case WLAN_CIPHER_SUITE_WEP104:
	hk.kv_type = ATH_CIPHER_WEP;
	break;
	case WLAN_CIPHER_SUITE_TKIP:
	hk.kv_type = ATH_CIPHER_TKIP;
	break;
	case WLAN_CIPHER_SUITE_CCMP:
	hk.kv_type = ATH_CIPHER_AES_CCM;
	break;
	default:
	return -EOPNOTSUPP;
	}

	hk.kv_len = key->keylen;
	if (key->keylen)
	memcpy(hk.kv_val, key->key, key->keylen);

	if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
	switch (vif->type) {
	case NL80211_IFTYPE_AP:
	memcpy(gmac, vif->addr, ETH_ALEN);
	gmac[0] \|= 0x01;
	mac = gmac;
	idx = ath_reserve_key_cache_slot(common, key->cipher);
	break;
	case NL80211_IFTYPE_ADHOC:
	if (!sta) {
	idx = key->keyidx;
	break;
	}
	memcpy(gmac, sta->addr, ETH_ALEN);
	gmac[0] \|= 0x01;
	mac = gmac;
	idx = ath_reserve_key_cache_slot(common, key->cipher);
	break;
	default:
	idx = key->keyidx;
	break;
	}
	} else if (key->keyidx) {
	if (WARN_ON(!sta))
	return -EOPNOTSUPP;
	mac = sta->addr;

	if (vif->type != NL80211_IFTYPE_AP) {
	/* Only keyidx 0 should be used with unicast key, but
	* allow this for client mode for now. */
	idx = key->keyidx;
	} else
	return -EIO;
	} else {
	if (WARN_ON(!sta))
	return -EOPNOTSUPP;
	mac = sta->addr;

	idx = ath_reserve_key_cache_slot(common, key->cipher);
	}

	if (idx < 0)
	return -ENOSPC; /* no free key cache entries */

	if (key->cipher == WLAN_CIPHER_SUITE_TKIP)
	ret = ath_setkey_tkip(common, idx, key->key, &hk, mac,
	vif->type == NL80211_IFTYPE_AP);
	else
	ret = ath_hw_set_keycache_entry(common, idx, &hk, mac);

	if (!ret)
	return -EIO;

	set_bit(idx, common->keymap);
	if (key->cipher == WLAN_CIPHER_SUITE_TKIP) {
	set_bit(idx + 64, common->keymap);
	set_bit(idx, common->tkip_keymap);
	set_bit(idx + 64, common->tkip_keymap);
	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
	set_bit(idx + 32, common->keymap);
	set_bit(idx + 64 + 32, common->keymap);
	set_bit(idx + 32, common->tkip_keymap);
	set_bit(idx + 64 + 32, common->tkip_keymap);
	}
	}

	return idx;
	}
	EXPORT_SYMBOL(ath_key_config);

	/*
	* Delete Key.
	*/
	void ath_key_delete(struct ath_common common, struct ieee80211_key_conf key)
	{
	ath_hw_keyreset(common, key->hw_key_idx);
	if (key->hw_key_idx < IEEE80211_WEP_NKID)
	return;

	clear_bit(key->hw_key_idx, common->keymap);
	if (key->cipher != WLAN_CIPHER_SUITE_TKIP)
	return;

	clear_bit(key->hw_key_idx + 64, common->keymap);

	clear_bit(key->hw_key_idx, common->tkip_keymap);
	clear_bit(key->hw_key_idx + 64, common->tkip_keymap);

	if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) {
	ath_hw_keyreset(common, key->hw_key_idx + 32);
	clear_bit(key->hw_key_idx + 32, common->keymap);
	clear_bit(key->hw_key_idx + 64 + 32, common->keymap);

	clear_bit(key->hw_key_idx + 32, common->tkip_keymap);
	clear_bit(key->hw_key_idx + 64 + 32, common->tkip_keymap);
	}
	}
	EXPORT_SYMBOL(ath_key_delete);