Re: [Curdle] new-AD review comments on draft-ietf-curdle-gss-keyex-sha2-08

[Hubert Kario <[e-mail]>]

On Wednesday, 8 May 2019 17:06:04 CEST Benjamin Kaduk wrote:
> Hi all,
> 
> I'm almost ready to send draft-ietf-curdle-gss-keyex-sha2 to the IESG for
> evaluation, but would like to see a new revision posted first, mostly for
> the Abstract changes.  In addition to the changes mentioned below, please
> also go ahead and make the editorial changes mentioned in the last
> call/directorate reviews.
> 
> -Ben
> 
> Abstract
> 
>    This document specifies additions and amendments to RFC4462.  It
>    defines a new key exchange method that uses SHA-2 for integrity and
>    deprecates weak DH groups.  The purpose of this specification is to
> 
> I think we need to remove this statement about "deprecates weak DH groups";
> I didn't see any further discussion of such deprecations in any revision of
> the document.


we've done that by not listing them, would you prefer to list them explicitly 
in section 6 and Section 4 with a "MUST NOT" in "Implementation Support" and 
"Implementation Recommendations"?
 
> Section 2
> 
>                                                            Following the
>    rationale of [RFC8268] only SHA-256 and SHA-512 hashes are used for
>    DH groups.  For NIST curves the same curve-to-hashing algorithm
>    pairing used in [RFC5656] is adopted for consistency.
> 
> 8268 doesn't provide a whole lot of rationale for using SHA-256, rather,
> the closest thing to guidance would be in Section 1 where it cites the NSA
> IAD FAQ that wants to *avoid* using SHA-256.  So perhaps it's better to say
> that this just follows the practice of 8268, rather than the rationale from
> it, especially since we are just using a "consistency" argument for the
> NIST curves' hashes.

yes, "practice" would work better in this context

-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purkyňova 115, 612 00  Brno, Czech Republic