| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * DES & Triple DES EDE key verification helpers |
| */ |
| |
| #ifndef __CRYPTO_INTERNAL_DES_H |
| #define __CRYPTO_INTERNAL_DES_H |
| |
| #include <linux/crypto.h> |
| #include <linux/fips.h> |
| #include <crypto/des.h> |
| #include <crypto/aead.h> |
| #include <crypto/skcipher.h> |
| |
| /** |
| * crypto_des_verify_key - Check whether a DES key is weak |
| * @tfm: the crypto algo |
| * @key: the key buffer |
| * |
| * Returns -EINVAL if the key is weak and the crypto TFM does not permit weak |
| * keys. Otherwise, 0 is returned. |
| * |
| * It is the job of the caller to ensure that the size of the key equals |
| * DES_KEY_SIZE. |
| */ |
| static inline int crypto_des_verify_key(struct crypto_tfm *tfm, const u8 *key) |
| { |
| struct des_ctx tmp; |
| int err; |
| |
| err = des_expand_key(&tmp, key, DES_KEY_SIZE); |
| if (err == -ENOKEY) { |
| if (crypto_tfm_get_flags(tfm) & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS) |
| err = -EINVAL; |
| else |
| err = 0; |
| } |
| |
| if (err) |
| crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY); |
| |
| memzero_explicit(&tmp, sizeof(tmp)); |
| return err; |
| } |
| |
| /* |
| * RFC2451: |
| * |
| * For DES-EDE3, there is no known need to reject weak or |
| * complementation keys. Any weakness is obviated by the use of |
| * multiple keys. |
| * |
| * However, if the first two or last two independent 64-bit keys are |
| * equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the |
| * same as DES. Implementers MUST reject keys that exhibit this |
| * property. |
| * |
| */ |
| static inline int des3_ede_verify_key(const u8 *key, unsigned int key_len, |
| bool check_weak) |
| { |
| int ret = fips_enabled ? -EINVAL : -ENOKEY; |
| u32 K[6]; |
| |
| memcpy(K, key, DES3_EDE_KEY_SIZE); |
| |
| if ((!((K[0] ^ K[2]) | (K[1] ^ K[3])) || |
| !((K[2] ^ K[4]) | (K[3] ^ K[5]))) && |
| (fips_enabled || check_weak)) |
| goto bad; |
| |
| if ((!((K[0] ^ K[4]) | (K[1] ^ K[5]))) && fips_enabled) |
| goto bad; |
| |
| ret = 0; |
| bad: |
| memzero_explicit(K, DES3_EDE_KEY_SIZE); |
| |
| return ret; |
| } |
| |
| /** |
| * crypto_des3_ede_verify_key - Check whether a DES3-EDE key is weak |
| * @tfm: the crypto algo |
| * @key: the key buffer |
| * |
| * Returns -EINVAL if the key is weak and the crypto TFM does not permit weak |
| * keys or when running in FIPS mode. Otherwise, 0 is returned. Note that some |
| * keys are rejected in FIPS mode even if weak keys are permitted by the TFM |
| * flags. |
| * |
| * It is the job of the caller to ensure that the size of the key equals |
| * DES3_EDE_KEY_SIZE. |
| */ |
| static inline int crypto_des3_ede_verify_key(struct crypto_tfm *tfm, |
| const u8 *key) |
| { |
| int err; |
| |
| err = des3_ede_verify_key(key, DES3_EDE_KEY_SIZE, |
| crypto_tfm_get_flags(tfm) & |
| CRYPTO_TFM_REQ_FORBID_WEAK_KEYS); |
| if (err) |
| crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY); |
| return err; |
| } |
| |
| static inline int verify_skcipher_des_key(struct crypto_skcipher *tfm, |
| const u8 *key) |
| { |
| return crypto_des_verify_key(crypto_skcipher_tfm(tfm), key); |
| } |
| |
| static inline int verify_skcipher_des3_key(struct crypto_skcipher *tfm, |
| const u8 *key) |
| { |
| return crypto_des3_ede_verify_key(crypto_skcipher_tfm(tfm), key); |
| } |
| |
| static inline int verify_ablkcipher_des_key(struct crypto_ablkcipher *tfm, |
| const u8 *key) |
| { |
| return crypto_des_verify_key(crypto_ablkcipher_tfm(tfm), key); |
| } |
| |
| static inline int verify_ablkcipher_des3_key(struct crypto_ablkcipher *tfm, |
| const u8 *key) |
| { |
| return crypto_des3_ede_verify_key(crypto_ablkcipher_tfm(tfm), key); |
| } |
| |
| static inline int verify_aead_des_key(struct crypto_aead *tfm, const u8 *key, |
| int keylen) |
| { |
| if (keylen != DES_KEY_SIZE) { |
| crypto_aead_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
| return -EINVAL; |
| } |
| return crypto_des_verify_key(crypto_aead_tfm(tfm), key); |
| } |
| |
| static inline int verify_aead_des3_key(struct crypto_aead *tfm, const u8 *key, |
| int keylen) |
| { |
| if (keylen != DES3_EDE_KEY_SIZE) { |
| crypto_aead_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
| return -EINVAL; |
| } |
| return crypto_des3_ede_verify_key(crypto_aead_tfm(tfm), key); |
| } |
| |
| #endif /* __CRYPTO_INTERNAL_DES_H */ |