Re: [Cfrg] On the (non-)randomness of the S-box of Streebog and Kuznyechik

[Dmitry Belyavsky <[e-mail]>]

On Tue, Aug 6, 2019 at 5:13 PM Stephen Farrell <[e-mail]>
wrote:

>
> Hiya,
>
> On 06/08/2019 15:09, Dmitry Belyavsky wrote:
> > Dear Stephen,
> >
> > RFC 7091 seems to be a translation of the corresponding GOST standard.
> >
> > RFC 8624 contains a reference to RFC5933, where the GOST algorithms for
> > DNSSec were introduced.
> > The reference is correct, the reference to the superseding algorithms is
> > correct too.
>
> I'm not getting it. Why does 8624 need a normative
> reference to 6986 and an informative reference to
> 5933 when the code points refer to the algorithms
> defined in 5933?
>
> S.
>

In fact, the reference to 5933 is normative (in part of  DNSSec).

Then we have reference to the superseding algorithms which personally I
tend to treat as informative.
It explains why the GOST algorithms have the status MUST NOT for
signing/delegation.


>
> >
> > So it seems that no errata required here.
> >
> >
> > On Tue, Aug 6, 2019 at 4:56 PM Stanislav V. Smyshlyaev <
> [e-mail]>
> > wrote:
> >
> >> Dear Stephen,
> >>
> >>>> So that sounds like an erratum may be worthwhile for each of 8624 and
> >> 7901? I guess the code points defined for DNSSEC are really for the old
> >> algorithms and ought not point to the RFCs for the new ones?
> >>>> And that hasn't really got anything to do with the meat of Leo's
> >> findings - it's just that his work flagged up the erroneous references.
> >> Personally, I agree that it would be good to do the updates here. But,
> as
> >> for DNSSEC, I hope that the authors of RFC 5933 (or, maybe, Dmitry
> >> Belyavsky) can comment better.
> >>
> >>
> >>
> >> вт, 6 авг. 2019 г. в 16:33, Stephen Farrell <[e-mail]
> >:
> >>
> >>>
> >>> Hiya,
> >>>
> >>> On 06/08/2019 14:14, Stanislav V. Smyshlyaev wrote:
> >>>> Stephen, GOST R 34.11-94 is built using a completely different
> >>>> construction, so (Leo will correct me, if I am mistaken) the
> discovered
> >>>> properties are not related to GOST R 34.11-94. I’d also like to
> clarify
> >>>> that this GOST R 34.11-94 is an old hash function, which has been
> >>>> deprecated for about 7 years in Russia.
> >>>
> >>> So that sounds like an erratum may be worthwhile
> >>> for each of 8624 and 7901? I guess the code points
> >>> defined for DNSSEC are really for the old algorithms
> >>> and ought not point to the RFCs for the new ones?
> >>> Those'd be valid errata I reckon, as it was a bit
> >>> of a mistake (though entirely understandable) to
> >>> refer to the new RFCs when the code points are for
> >>> the old algorithms. Those errata would just say
> >>> that the normative references to the new RFC were
> >>> wrong and should've been to the old RFC. And that
> >>> hasn't really got anything to do with the meat of
> >>> Leo's findings - it's just that his work flagged
> >>> up the erroneous references.
> >>>
> >>> As to whether to deprecate the algorithms due to
> >>> Leo's findings, I agree that the existence of
> >>> deployments that'd be affected needs to be taken
> >>> into account in terms of the timing of when that
> >>> might reasonably be done. And the fact that the
> >>> algorithms in question are national standards is
> >>> also a relevant point, though of course deprecating
> >>> the RFCs has no formal effect on such national
> >>> standards.
> >>>
> >>> Personally though, I think discovery of undeclared
> >>> and unexplained structure such as this in a crypto
> >>> algorithm ought be taken as a negative, even if there
> >>> is no known attack at present, so I'd be for moving
> >>> to deprecate when that is practical, in this case,
> >>> as I would in any other similar case.
> >>>
> >>> Cheers,
> >>> S.
> >>>
> >>
> >
>


-- 
SY, Dmitry Belyavsky