/*
* 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, 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, 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, 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_CCMP)
set_bit(idx, common->ccmp_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);
clear_bit(key->hw_key_idx, common->ccmp_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);
