1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <crypto/b128ops.h>
6 #include <crypto/internal/skcipher.h>
7 #include <linux/fips.h>
10 struct blkcipher_desc;
12 #define XTS_BLOCK_SIZE 16
14 struct xts_crypt_req {
19 void (*tweak_fn)(void *ctx, u8* dst, const u8* src);
21 void (*crypt_fn)(void *ctx, u8 *blks, unsigned int nbytes);
24 #define XTS_TWEAK_CAST(x) ((void (*)(void *, u8*, const u8*))(x))
26 int xts_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
27 struct scatterlist *src, unsigned int nbytes,
28 struct xts_crypt_req *req);
30 static inline int xts_check_key(struct crypto_tfm *tfm,
31 const u8 *key, unsigned int keylen)
33 u32 *flags = &tfm->crt_flags;
36 * key consists of keys of equal size concatenated, therefore
37 * the length must be even.
40 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
44 /* ensure that the AES and tweak key are not identical */
46 !crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
47 *flags |= CRYPTO_TFM_RES_WEAK_KEY;
54 static inline int xts_verify_key(struct crypto_skcipher *tfm,
55 const u8 *key, unsigned int keylen)
58 * key consists of keys of equal size concatenated, therefore
59 * the length must be even.
62 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
66 /* ensure that the AES and tweak key are not identical */
67 if ((fips_enabled || crypto_skcipher_get_flags(tfm) &
68 CRYPTO_TFM_REQ_WEAK_KEY) &&
69 !crypto_memneq(key, key + (keylen / 2), keylen / 2)) {
70 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY);
77 #endif /* _CRYPTO_XTS_H */