[mirror_ubuntu-zesty-kernel.git] / include / crypto / xts.h

#ifndef _CRYPTO_XTS_H
#define _CRYPTO_XTS_H

#include <crypto/b128ops.h>
#include <crypto/internal/skcipher.h>
#include <linux/fips.h>

struct scatterlist;
struct blkcipher_desc;

#define XTS_BLOCK_SIZE 16

struct xts_crypt_req {
	be128 *tbuf;
	unsigned int tbuflen;

	void *tweak_ctx;
	void (*tweak_fn)(void *ctx, u8* dst, const u8* src);
	void *crypt_ctx;
	void (*crypt_fn)(void *ctx, u8 *blks, unsigned int nbytes);
};

#define XTS_TWEAK_CAST(x) ((void (*)(void *, u8*, const u8*))(x))

int xts_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
	      struct scatterlist *src, unsigned int nbytes,
	      struct xts_crypt_req *req);

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 */
Commit	Line	Data
ce004556 JK	1	#ifndef _CRYPTO_XTS_H
	2	#define _CRYPTO_XTS_H
	3
	4	#include <crypto/b128ops.h>
f1c131b4	5	#include <crypto/internal/skcipher.h>
28856a9e	6	#include <linux/fips.h>
ce004556 JK	7
	8	struct scatterlist;
	9	struct blkcipher_desc;
	10
	11	#define XTS_BLOCK_SIZE 16
	12
	13	struct xts_crypt_req {
	14	be128 *tbuf;
	15	unsigned int tbuflen;
	16
	17	void *tweak_ctx;
	18	void (tweak_fn)(void ctx, u8* dst, const u8* src);
	19	void *crypt_ctx;
	20	void (crypt_fn)(void ctx, u8 *blks, unsigned int nbytes);
	21	};
	22
	23	#define XTS_TWEAK_CAST(x) ((void ()(void , u8, const u8))(x))
	24
	25	int xts_crypt(struct blkcipher_desc desc, struct scatterlist dst,
	26	struct scatterlist *src, unsigned int nbytes,
	27	struct xts_crypt_req *req);
	28
28856a9e SM	29	static inline int xts_check_key(struct crypto_tfm *tfm,
	30	const u8 *key, unsigned int keylen)
	31	{
	32	u32 *flags = &tfm->crt_flags;
	33
	34	/*
	35	* key consists of keys of equal size concatenated, therefore
	36	* the length must be even.
	37	*/
	38	if (keylen % 2) {
	39	*flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	40	return -EINVAL;
	41	}
	42
	43	/* ensure that the AES and tweak key are not identical */
	44	if (fips_enabled &&
	45	!crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
	46	*flags \|= CRYPTO_TFM_RES_WEAK_KEY;
	47	return -EINVAL;
	48	}
	49
	50	return 0;
	51	}
	52
f1c131b4 HX	53	static inline int xts_verify_key(struct crypto_skcipher *tfm,
	54	const u8 *key, unsigned int keylen)
	55	{
	56	/*
	57	* key consists of keys of equal size concatenated, therefore
	58	* the length must be even.
	59	*/
	60	if (keylen % 2) {
	61	crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	62	return -EINVAL;
	63	}
	64
	65	/* ensure that the AES and tweak key are not identical */
	66	if ((fips_enabled \|\| crypto_skcipher_get_flags(tfm) &
	67	CRYPTO_TFM_REQ_WEAK_KEY) &&
	68	!crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
	69	crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY);
	70	return -EINVAL;
	71	}
	72
	73	return 0;
	74	}
	75
ce004556	76	#endif /* _CRYPTO_XTS_H */