projects / linux.git / blame
| 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 { | |
| e55318c8 | 14 | le128 *tbuf; |
| ce004556 JK |
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 */ |