Re: [PATCH 12/17] crypto/builtin: Merge qcrypto_cipher_aes_{ecb,xts}_{en,de}crypt

[Daniel P . Berrangé]

On Wed, Aug 12, 2020 at 08:25:32PM -0700, Richard Henderson wrote:
> There's no real reason we need two separate helper functions here.
> Standardize on the function signature required for xts_encrypt.
> Rename to do_aes_{en,de}crypt_ecb, since the helper does not
> itself do anything with respect to xts.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  crypto/cipher-builtin.inc.c | 69 ++++++++++---------------------------
>  1 file changed, 18 insertions(+), 51 deletions(-)
> 
> diff --git a/crypto/cipher-builtin.inc.c b/crypto/cipher-builtin.inc.c
> index e2ae5d090c..4d971a2b82 100644
> --- a/crypto/cipher-builtin.inc.c
> +++ b/crypto/cipher-builtin.inc.c
> @@ -72,65 +72,34 @@ static void qcrypto_cipher_free_aes(QCryptoCipher *cipher)
>      g_free(cipher);
>  }
>  
> -
> -static void qcrypto_cipher_aes_ecb_encrypt(const AES_KEY *key,
> -                                           const void *in,
> -                                           void *out,
> -                                           size_t len)
> +static void do_aes_encrypt_ecb(const void *vctx, size_t len,
> +                               uint8_t *out, const uint8_t *in)

nitpick - stick with the 1-arg-per-line style, instead of packing
args.

>  {
> -    const uint8_t *inptr = in;
> -    uint8_t *outptr = out;
> +    const QCryptoCipherBuiltinAESContext *ctx = vctx;
>  
>      /* We have already verified that len % AES_BLOCK_SIZE == 0. */
>      while (len) {
> -        AES_encrypt(inptr, outptr, key);
> -        inptr += AES_BLOCK_SIZE;
> -        outptr += AES_BLOCK_SIZE;
> +        AES_encrypt(in, out, &ctx->enc);
> +        in += AES_BLOCK_SIZE;
> +        out += AES_BLOCK_SIZE;
>          len -= AES_BLOCK_SIZE;
>      }
>  }
>  
> -
> -static void qcrypto_cipher_aes_ecb_decrypt(const AES_KEY *key,
> -                                           const void *in,
> -                                           void *out,
> -                                           size_t len)
> +static void do_aes_decrypt_ecb(const void *vctx, size_t len,
> +                               uint8_t *out, const uint8_t *in)
>  {
> -    const uint8_t *inptr = in;
> -    uint8_t *outptr = out;
> +    const QCryptoCipherBuiltinAESContext *ctx = vctx;
>  
>      /* We have already verified that len % AES_BLOCK_SIZE == 0. */
>      while (len) {
> -        AES_decrypt(inptr, outptr, key);
> -        inptr += AES_BLOCK_SIZE;
> -        outptr += AES_BLOCK_SIZE;
> +        AES_decrypt(in, out, &ctx->dec);
> +        in += AES_BLOCK_SIZE;
> +        out += AES_BLOCK_SIZE;
>          len -= AES_BLOCK_SIZE;
>      }
>  }
>  
> -
> -static void qcrypto_cipher_aes_xts_encrypt(const void *ctx,
> -                                           size_t length,
> -                                           uint8_t *dst,
> -                                           const uint8_t *src)
> -{
> -    const QCryptoCipherBuiltinAESContext *aesctx = ctx;
> -
> -    qcrypto_cipher_aes_ecb_encrypt(&aesctx->enc, src, dst, length);
> -}
> -
> -
> -static void qcrypto_cipher_aes_xts_decrypt(const void *ctx,
> -                                           size_t length,
> -                                           uint8_t *dst,
> -                                           const uint8_t *src)
> -{
> -    const QCryptoCipherBuiltinAESContext *aesctx = ctx;
> -
> -    qcrypto_cipher_aes_ecb_decrypt(&aesctx->dec, src, dst, length);
> -}
> -
> -

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
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