Re: [PATCH 1/8] crypto: hash: add zero length message hash for shax and md5

From: Herbert Xu
Date: Wed Oct 14 2015 - 06:08:37 EST


On Mon, Oct 12, 2015 at 06:53:39PM +0200, LABBE Corentin wrote:
> Some crypto drivers cannot process empty data message and return a
> precalculated hash for md5/sha1/sha224/sha256.
>
> This patch add thoses precalculated hash in include/crypto.
>
> Signed-off-by: LABBE Corentin <clabbe.montjoie@xxxxxxxxx>
> ---
> include/crypto/md5.h | 5 +++++
> include/crypto/sha.h | 20 ++++++++++++++++++++
> 2 files changed, 25 insertions(+)
>
> diff --git a/include/crypto/md5.h b/include/crypto/md5.h
> index 146af82..6496ee0 100644
> --- a/include/crypto/md5.h
> +++ b/include/crypto/md5.h
> @@ -13,6 +13,11 @@
> #define MD5_H2 0x98badcfeUL
> #define MD5_H3 0x10325476UL
>
> +static const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
> + 0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
> + 0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
> +};
> +

This potentially creates this structure in every file that includes
md5.h. How about putting it into md5_generic and exporting it?

> diff --git a/include/crypto/sha.h b/include/crypto/sha.h
> index dd7905a..02d7ffb 100644
> --- a/include/crypto/sha.h
> +++ b/include/crypto/sha.h
> @@ -64,6 +64,26 @@
> #define SHA512_H6 0x1f83d9abfb41bd6bULL
> #define SHA512_H7 0x5be0cd19137e2179ULL
>
> +static const u8 sha1_zero_message_hash[SHA1_DIGEST_SIZE] = {
> + 0xda, 0x39, 0xa3, 0xee, 0x5e, 0x6b, 0x4b, 0x0d,
> + 0x32, 0x55, 0xbf, 0xef, 0x95, 0x60, 0x18, 0x90,
> + 0xaf, 0xd8, 0x07, 0x09
> +};

Ditto.

Thanks,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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