Re: [PATCH] crypto: DRBG - switch to HMAC SHA512 DRBG as default DRBG

[Simo Sorce <simo@redhat.com>]

On Thu, 2021-05-20 at 21:31 +0200, Stephan Müller wrote:
> The default DRBG is the one that has the highest priority. The priority
> is defined based on the order of the list drbg_cores[] where the highest
> priority is given to the last entry by drbg_fill_array.
> 
> With this patch the default DRBG is switched from HMAC SHA256 to HMAC
> SHA512 to support compliance with SP800-90B and SP800-90C (current
> draft).
> 
> The user of the crypto API is completely unaffected by the change.
> 
> Signed-off-by: Stephan Mueller <smueller@chronox.de>
> ---
>  crypto/drbg.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/crypto/drbg.c b/crypto/drbg.c
> index 1b4587e0ddad..ea85d4a0fe9e 100644
> --- a/crypto/drbg.c
> +++ b/crypto/drbg.c
> @@ -176,18 +176,18 @@ static const struct drbg_core drbg_cores[] = {
>  		.blocklen_bytes = 48,
>  		.cra_name = "hmac_sha384",
>  		.backend_cra_name = "hmac(sha384)",
> -	}, {
> -		.flags = DRBG_HMAC | DRBG_STRENGTH256,
> -		.statelen = 64, /* block length of cipher */
> -		.blocklen_bytes = 64,
> -		.cra_name = "hmac_sha512",
> -		.backend_cra_name = "hmac(sha512)",
>  	}, {
>  		.flags = DRBG_HMAC | DRBG_STRENGTH256,
>  		.statelen = 32, /* block length of cipher */
>  		.blocklen_bytes = 32,
>  		.cra_name = "hmac_sha256",
>  		.backend_cra_name = "hmac(sha256)",
> +	}, {
> +		.flags = DRBG_HMAC | DRBG_STRENGTH256,
> +		.statelen = 64, /* block length of cipher */
> +		.blocklen_bytes = 64,
> +		.cra_name = "hmac_sha512",
> +		.backend_cra_name = "hmac(sha512)",
>  	},
>  #endif /* CONFIG_CRYPTO_DRBG_HMAC */
>  };

We'd like this to ease certification pains.
Acked-by: simo Sorce <simo@redhat.com>

-- 
Simo Sorce
RHEL Crypto Team
Red Hat, Inc