61 lines
1.4 KiB
C
61 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _CRYPTO_XTS_H
|
|
#define _CRYPTO_XTS_H
|
|
|
|
#include <crypto/b128ops.h>
|
|
#include <crypto/internal/skcipher.h>
|
|
#include <linux/fips.h>
|
|
|
|
#define XTS_BLOCK_SIZE 16
|
|
|
|
#define XTS_TWEAK_CAST(x) ((void (*)(void *, u8*, const u8*))(x))
|
|
|
|
static inline int xts_check_key(struct crypto_tfm *tfm,
|
|
const u8 *key, unsigned int keylen)
|
|
{
|
|
u32 *flags = &tfm->crt_flags;
|
|
|
|
/*
|
|
* key consists of keys of equal size concatenated, therefore
|
|
* the length must be even.
|
|
*/
|
|
if (keylen % 2) {
|
|
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* ensure that the AES and tweak key are not identical */
|
|
if (fips_enabled &&
|
|
!crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
|
|
*flags |= CRYPTO_TFM_RES_WEAK_KEY;
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int xts_verify_key(struct crypto_skcipher *tfm,
|
|
const u8 *key, unsigned int keylen)
|
|
{
|
|
/*
|
|
* key consists of keys of equal size concatenated, therefore
|
|
* the length must be even.
|
|
*/
|
|
if (keylen % 2) {
|
|
crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* ensure that the AES and tweak key are not identical */
|
|
if ((fips_enabled || crypto_skcipher_get_flags(tfm) &
|
|
CRYPTO_TFM_REQ_WEAK_KEY) &&
|
|
!crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
|
|
crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif /* _CRYPTO_XTS_H */
|