1ce004556SJussi Kivilinna #ifndef _CRYPTO_XTS_H 2ce004556SJussi Kivilinna #define _CRYPTO_XTS_H 3ce004556SJussi Kivilinna 4ce004556SJussi Kivilinna #include <crypto/b128ops.h> 5*28856a9eSStephan Mueller #include <linux/crypto.h> 6*28856a9eSStephan Mueller #include <crypto/algapi.h> 7*28856a9eSStephan Mueller #include <linux/fips.h> 8ce004556SJussi Kivilinna 9ce004556SJussi Kivilinna struct scatterlist; 10ce004556SJussi Kivilinna struct blkcipher_desc; 11ce004556SJussi Kivilinna 12ce004556SJussi Kivilinna #define XTS_BLOCK_SIZE 16 13ce004556SJussi Kivilinna 14ce004556SJussi Kivilinna struct xts_crypt_req { 15ce004556SJussi Kivilinna be128 *tbuf; 16ce004556SJussi Kivilinna unsigned int tbuflen; 17ce004556SJussi Kivilinna 18ce004556SJussi Kivilinna void *tweak_ctx; 19ce004556SJussi Kivilinna void (*tweak_fn)(void *ctx, u8* dst, const u8* src); 20ce004556SJussi Kivilinna void *crypt_ctx; 21ce004556SJussi Kivilinna void (*crypt_fn)(void *ctx, u8 *blks, unsigned int nbytes); 22ce004556SJussi Kivilinna }; 23ce004556SJussi Kivilinna 24ce004556SJussi Kivilinna #define XTS_TWEAK_CAST(x) ((void (*)(void *, u8*, const u8*))(x)) 25ce004556SJussi Kivilinna 26ce004556SJussi Kivilinna int xts_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, 27ce004556SJussi Kivilinna struct scatterlist *src, unsigned int nbytes, 28ce004556SJussi Kivilinna struct xts_crypt_req *req); 29ce004556SJussi Kivilinna 30*28856a9eSStephan Mueller static inline int xts_check_key(struct crypto_tfm *tfm, 31*28856a9eSStephan Mueller const u8 *key, unsigned int keylen) 32*28856a9eSStephan Mueller { 33*28856a9eSStephan Mueller u32 *flags = &tfm->crt_flags; 34*28856a9eSStephan Mueller 35*28856a9eSStephan Mueller /* 36*28856a9eSStephan Mueller * key consists of keys of equal size concatenated, therefore 37*28856a9eSStephan Mueller * the length must be even. 38*28856a9eSStephan Mueller */ 39*28856a9eSStephan Mueller if (keylen % 2) { 40*28856a9eSStephan Mueller *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 41*28856a9eSStephan Mueller return -EINVAL; 42*28856a9eSStephan Mueller } 43*28856a9eSStephan Mueller 44*28856a9eSStephan Mueller /* ensure that the AES and tweak key are not identical */ 45*28856a9eSStephan Mueller if (fips_enabled && 46*28856a9eSStephan Mueller !crypto_memneq(key, key + (keylen / 2), keylen / 2)) { 47*28856a9eSStephan Mueller *flags |= CRYPTO_TFM_RES_WEAK_KEY; 48*28856a9eSStephan Mueller return -EINVAL; 49*28856a9eSStephan Mueller } 50*28856a9eSStephan Mueller 51*28856a9eSStephan Mueller return 0; 52*28856a9eSStephan Mueller } 53*28856a9eSStephan Mueller 54ce004556SJussi Kivilinna #endif /* _CRYPTO_XTS_H */ 55