freebsd-dev/sys/dev/ath/ath_hal/ar5212/ar5212_keycache.c
Adrian Chadd be97670785 Fix the keycache behaviour for multicast keycache search.
The correct bit to set is 0x1 in the high MAC address byte, not 0x80.
The hardware isn't programmed with that bit (which is the multicast
adress bit.)

The linux ath9k keycache code uses that bit in the MAC as a "this is
a multicast key!" and doesn't set the AR_KEYTABLE_VALID bit.
This tells the hardware the MAC isn't to be used for unicast destination
matching but it can be used for multicast bssid traffic.

This fixes some encryption problems in station mode.

PR: kern/154598
2011-02-09 15:23:16 +00:00

303 lines
9.5 KiB
C

/*
* Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
* Copyright (c) 2002-2008 Atheros Communications, Inc.
*
* 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.
*
* $FreeBSD$
*/
#include "opt_ah.h"
#include "ah.h"
#include "ah_internal.h"
#include "ar5212/ar5212.h"
#include "ar5212/ar5212reg.h"
#include "ar5212/ar5212desc.h"
/*
* Note: The key cache hardware requires that each double-word
* pair be written in even/odd order (since the destination is
* a 64-bit register). Don't reorder the writes in this code
* w/o considering this!
*/
#define KEY_XOR 0xaa
#define IS_MIC_ENABLED(ah) \
(AH5212(ah)->ah_staId1Defaults & AR_STA_ID1_CRPT_MIC_ENABLE)
/*
* Return the size of the hardware key cache.
*/
uint32_t
ar5212GetKeyCacheSize(struct ath_hal *ah)
{
return AH_PRIVATE(ah)->ah_caps.halKeyCacheSize;
}
/*
* Return true if the specific key cache entry is valid.
*/
HAL_BOOL
ar5212IsKeyCacheEntryValid(struct ath_hal *ah, uint16_t entry)
{
if (entry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
uint32_t val = OS_REG_READ(ah, AR_KEYTABLE_MAC1(entry));
if (val & AR_KEYTABLE_VALID)
return AH_TRUE;
}
return AH_FALSE;
}
/*
* Clear the specified key cache entry and any associated MIC entry.
*/
HAL_BOOL
ar5212ResetKeyCacheEntry(struct ath_hal *ah, uint16_t entry)
{
uint32_t keyType;
if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
__func__, entry);
return AH_FALSE;
}
keyType = OS_REG_READ(ah, AR_KEYTABLE_TYPE(entry));
/* XXX why not clear key type/valid bit first? */
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);
if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
uint16_t micentry = entry+64; /* MIC goes at slot+64 */
HALASSERT(micentry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
/* NB: key type and MAC are known to be ok */
}
return AH_TRUE;
}
/*
* Sets the mac part of the specified key cache entry (and any
* associated MIC entry) and mark them valid.
*
* Since mac[0] is shifted off and not presented to the hardware,
* it does double duty as a "don't use for unicast, use for multicast
* matching" flag. This interface should later be extended to
* explicitly do that rather than overloading a bit in the MAC
* address.
*/
HAL_BOOL
ar5212SetKeyCacheEntryMac(struct ath_hal *ah, uint16_t entry, const uint8_t *mac)
{
uint32_t macHi, macLo;
uint32_t unicast_flag = AR_KEYTABLE_VALID;
if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
__func__, entry);
return AH_FALSE;
}
/*
* Set MAC address -- shifted right by 1. MacLo is
* the 4 MSBs, and MacHi is the 2 LSBs.
*/
if (mac != AH_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;
macHi = (mac[5] << 8) | mac[4];
macLo = (mac[3] << 24)| (mac[2] << 16)
| (mac[1] << 8) | mac[0];
macLo >>= 1;
macLo |= (macHi & 1) << 31; /* carry */
macHi >>= 1;
} else {
macLo = macHi = 0;
}
OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);
return AH_TRUE;
}
/*
* Sets the contents of the specified key cache entry
* and any associated MIC entry.
*/
HAL_BOOL
ar5212SetKeyCacheEntry(struct ath_hal *ah, uint16_t entry,
const HAL_KEYVAL *k, const uint8_t *mac,
int xorKey)
{
struct ath_hal_5212 *ahp = AH5212(ah);
const HAL_CAPABILITIES *pCap = &AH_PRIVATE(ah)->ah_caps;
uint32_t key0, key1, key2, key3, key4;
uint32_t keyType;
uint32_t xorMask = xorKey ?
(KEY_XOR << 24 | KEY_XOR << 16 | KEY_XOR << 8 | KEY_XOR) : 0;
if (entry >= pCap->halKeyCacheSize) {
HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
__func__, entry);
return AH_FALSE;
}
switch (k->kv_type) {
case HAL_CIPHER_AES_OCB:
keyType = AR_KEYTABLE_TYPE_AES;
break;
case HAL_CIPHER_AES_CCM:
if (!pCap->halCipherAesCcmSupport) {
HALDEBUG(ah, HAL_DEBUG_ANY,
"%s: AES-CCM not supported by mac rev 0x%x\n",
__func__, AH_PRIVATE(ah)->ah_macRev);
return AH_FALSE;
}
keyType = AR_KEYTABLE_TYPE_CCM;
break;
case HAL_CIPHER_TKIP:
keyType = AR_KEYTABLE_TYPE_TKIP;
if (IS_MIC_ENABLED(ah) && entry+64 >= pCap->halKeyCacheSize) {
HALDEBUG(ah, HAL_DEBUG_ANY,
"%s: entry %u inappropriate for TKIP\n",
__func__, entry);
return AH_FALSE;
}
break;
case HAL_CIPHER_WEP:
if (k->kv_len < 40 / NBBY) {
HALDEBUG(ah, HAL_DEBUG_ANY,
"%s: WEP key length %u too small\n",
__func__, k->kv_len);
return AH_FALSE;
}
if (k->kv_len <= 40 / NBBY)
keyType = AR_KEYTABLE_TYPE_40;
else if (k->kv_len <= 104 / NBBY)
keyType = AR_KEYTABLE_TYPE_104;
else
keyType = AR_KEYTABLE_TYPE_128;
break;
case HAL_CIPHER_CLR:
keyType = AR_KEYTABLE_TYPE_CLR;
break;
default:
HALDEBUG(ah, HAL_DEBUG_ANY, "%s: cipher %u not supported\n",
__func__, k->kv_type);
return AH_FALSE;
}
key0 = LE_READ_4(k->kv_val+0) ^ xorMask;
key1 = (LE_READ_2(k->kv_val+4) ^ xorMask) & 0xffff;
key2 = LE_READ_4(k->kv_val+6) ^ xorMask;
key3 = (LE_READ_2(k->kv_val+10) ^ xorMask) & 0xffff;
key4 = LE_READ_4(k->kv_val+12) ^ xorMask;
if (k->kv_len <= 104 / NBBY)
key4 &= 0xff;
/*
* Note: key cache hardware requires that each double-word
* pair be written in even/odd order (since the destination is
* a 64-bit register). Don't reorder these writes w/o
* considering this!
*/
if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
uint16_t micentry = entry+64; /* MIC goes at slot+64 */
uint32_t mic0, mic1, mic2, mic3, mic4;
/*
* Invalidate the encrypt/decrypt key until the MIC
* key is installed so pending rx frames will fail
* with decrypt errors rather than a MIC error.
*/
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
/*
* Write MIC entry according to new or old key layout.
* The MISC_MODE register is assumed already set so
* these writes will be handled properly (happens on
* attach and at every reset).
*/
/* RX mic */
mic0 = LE_READ_4(k->kv_mic+0);
mic2 = LE_READ_4(k->kv_mic+4);
if (ahp->ah_miscMode & AR_MISC_MODE_MIC_NEW_LOC_ENABLE) {
/*
* Both RX and TX mic values can be combined into
* one cache slot entry:
* 8*N + 800 31:0 RX Michael key 0
* 8*N + 804 15:0 TX Michael key 0 [31:16]
* 8*N + 808 31:0 RX Michael key 1
* 8*N + 80C 15:0 TX Michael key 0 [15:0]
* 8*N + 810 31:0 TX Michael key 1
* 8*N + 814 15:0 reserved
* 8*N + 818 31:0 reserved
* 8*N + 81C 14:0 reserved
* 15 key valid == 0
*/
/* TX mic */
mic1 = LE_READ_2(k->kv_txmic+2) & 0xffff;
mic3 = LE_READ_2(k->kv_txmic+0) & 0xffff;
mic4 = LE_READ_4(k->kv_txmic+4);
} else {
mic1 = mic3 = mic4 = 0;
}
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
AR_KEYTABLE_TYPE_CLR);
/* NB: MIC key is not marked valid and has no MAC address */
OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);
/* correct intentionally corrupted key */
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
} else {
OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
}
return AH_TRUE;
}