Re: [PATCH 08/18] crypto: testmgr - run only subset of DH vectors based on config

[Hannes Reinecke <hare@suse.de>]

On 12/1/21 1:48 AM, Nicolai Stange wrote:
> With the previous patches, the testmgr now has up to four test vectors for
> DH which all test more or less the same thing:
> - the two vectors from before this series,
> - the vector for the ffdhe2048 group, enabled if
>    CONFIG_CRYPTO_DH_GROUPS_RFC7919 is set and
> - the vector for the modp2048 group, similarly enabled if
>    CONFIG_CRYPTO_DH_GROUPS_RFC3526 is set.
> 
> In order to avoid too much redundancy during DH testing, enable only a
> subset of these depending on the kernel config:
> - if CONFIG_CRYPTO_DH_GROUPS_RFC7919 is set, enable only the ffdhe2048
>    vector,
> - otherwise, if CONFIG_CRYPTO_DH_GROUPS_RFC3526 is set, enable only
>    the modp2048 vector and
> - only enable the original two vectors if neither of these options
>    has been selected.
> 
> Note that an upcoming patch will make the DH implementation to reject any
> domain parameters not corresponding to some safe-prime group approved by
> SP800-56Arev3 in FIPS mode. Thus, having CONFIG_FIPS enabled, but
> both of CONFIG_CRYPTO_DH_GROUPS_RFC7919 and
> CONFIG_CRYPTO_DH_GROUPS_RFC3526 unset wouldn't make much sense as it would
> render the DH implementation unusable in FIPS mode. Conversely, any
> reasonable configuration would ensure that the original, non-conforming
> test vectors would not get to run in FIPS mode.
> 

For some weird reason the NVMe spec mandates for its TLS profile the 
ffdhe3072 group, so I would prefer if you would be using that as the 
default group for testing.

> Signed-off-by: Nicolai Stange <nstange@suse.de>
> ---
>   crypto/testmgr.h | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/crypto/testmgr.h b/crypto/testmgr.h
> index d18844c7499e..b295512c8f22 100644
> --- a/crypto/testmgr.h
> +++ b/crypto/testmgr.h
> @@ -1331,8 +1331,7 @@ static const struct kpp_testvec dh_tv_template[] = {
>   	.expected_a_public_size = 256,
>   	.expected_ss_size = 256,
>   	},
> -#endif /* IS_ENABLED(CONFIG_CRYPTO_DH_GROUPS_RFC7919) */
> -#if IS_ENABLED(CONFIG_CRYPTO_DH_GROUPS_RFC3526)
> +#elif IS_ENABLED(CONFIG_CRYPTO_DH_GROUPS_RFC3526)
>   	{
>   	.secret =
>   #ifdef __LITTLE_ENDIAN
> @@ -1423,7 +1422,7 @@ static const struct kpp_testvec dh_tv_template[] = {
>   	.expected_a_public_size = 256,
>   	.expected_ss_size = 256,
>   	},
> -#endif /* IS_ENABLED(CONFIG_CRYPTO_DH_GROUPS_RFC3526) */
> +#else
>   	{
>   	.secret =
>   #ifdef __LITTLE_ENDIAN
> @@ -1642,6 +1641,7 @@ static const struct kpp_testvec dh_tv_template[] = {
>   	.expected_a_public_size = 256,
>   	.expected_ss_size = 256,
>   	},
> +#endif
>   };
>   
>   static const struct kpp_testvec curve25519_tv_template[] = {
> 
... and maybe add a config option to run a full test.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
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