Re: [Cfrg] Proposed requirements for curve candidate evaluation

Benjamin Black <b@b3k.us> Thu, 07 August 2014 19:01 UTC

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From: Benjamin Black <b@b3k.us>
Date: Thu, 7 Aug 2014 12:01:06 -0700
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To: Michael Hamburg <mike@shiftleft.org>
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Subject: Re: [Cfrg] Proposed requirements for curve candidate evaluation
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On Thu, Aug 7, 2014 at 11:57 AM, Michael Hamburg <mike@shiftleft.org> wrote:

>
> > On Aug 7, 2014, at 7:20 AM, Brian LaMacchia <bal@microsoft.com> wrote:
> > 2.    At each security level, the CFRG-recommended curve must be
> specified in a single curve model that is used for both digital signatures
> and key exchange algorithms (in particular ECDSA and ECDHE), without
> transformation to other models.
>
> To be clear, this “requirement” means that the curve must be specified in
> short Weierstrass form, right?
>
>
This requirement permits twisted Edwards. What it excludes is using
different models for different purposes.


Ben