Commit 51d8d6d0 authored by Herbert Xu's avatar Herbert Xu
Browse files

crypto: cipher - Add crypto_clone_cipher 



Allow simple ciphers to be cloned, if they don't have a cra_init
function.  This basically rules out those ciphers that require a
fallback.

In future simple ciphers will be eliminated, and replaced with a
linear skcipher interface.  When that happens this restriction will
disappear.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: default avatarArd Biesheuvel <ardb@kernel.org>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent cf2eddc9

crypto/cipher.c

+23 −0
Original line number Diff line number Diff line
@@ -90,3 +90,26 @@ void crypto_cipher_decrypt_one(struct crypto_cipher *tfm, 
	cipher_crypt_one(tfm, dst, src, false);

}

EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL);



struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher)

{

	struct crypto_tfm *tfm = crypto_cipher_tfm(cipher);

	struct crypto_alg *alg = tfm->__crt_alg;

	struct crypto_cipher *ncipher;

	struct crypto_tfm *ntfm;



	if (alg->cra_init)

		return ERR_PTR(-ENOSYS);



	ntfm = __crypto_alloc_tfm(alg, CRYPTO_ALG_TYPE_CIPHER,

				  CRYPTO_ALG_TYPE_MASK);

	if (IS_ERR(ntfm))

		return ERR_CAST(ntfm);



	ntfm->crt_flags = tfm->crt_flags;



	ncipher = __crypto_cipher_cast(ntfm);



	return ncipher;

}

EXPORT_SYMBOL_GPL(crypto_clone_cipher);

include/crypto/internal/cipher.h

+2 −0
Original line number Diff line number Diff line
@@ -176,6 +176,8 @@ void crypto_cipher_encrypt_one(struct crypto_cipher *tfm, 
void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,

			       u8 *dst, const u8 *src);



struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher);



struct crypto_cipher_spawn {

	struct crypto_spawn base;

};