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Diffstat (limited to '')
| -rw-r--r-- | include/crypto/xts.h | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/include/crypto/xts.h b/include/crypto/xts.h new file mode 100644 index 000000000..0f8dba69f --- /dev/null +++ b/include/crypto/xts.h @@ -0,0 +1,47 @@ +/* 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 + +static inline int xts_check_key(struct crypto_tfm *tfm, + const u8 *key, unsigned int keylen) +{ + /* + * key consists of keys of equal size concatenated, therefore + * the length must be even. + */ + if (keylen % 2) + return -EINVAL; + + /* ensure that the AES and tweak key are not identical */ + if (fips_enabled && !crypto_memneq(key, key + (keylen / 2), keylen / 2)) + 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) + return -EINVAL; + + /* ensure that the AES and tweak key are not identical */ + if ((fips_enabled || (crypto_skcipher_get_flags(tfm) & + CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)) && + !crypto_memneq(key, key + (keylen / 2), keylen / 2)) + return -EINVAL; + + return 0; +} + +#endif /* _CRYPTO_XTS_H */ |