Re: [Cfrg] Adoption of draft-agl-cfrgcurve-00 as a RG document

"Blumenthal, Uri - 0558 - MITLL" <uri@ll.mit.edu> Mon, 05 January 2015 20:27 UTC

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From: "Blumenthal, Uri - 0558 - MITLL" <uri@ll.mit.edu>
To: Adam Langley <agl@imperialviolet.org>
Thread-Topic: [Cfrg] Adoption of draft-agl-cfrgcurve-00 as a RG document
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Date: Mon, 5 Jan 2015 20:25:42 +0000
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Subject: Re: [Cfrg] Adoption of draft-agl-cfrgcurve-00 as a RG document
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On 1/5/15, 14:49 , "Adam Langley" <agl@imperialviolet.org> wrote:

>The structure of the current draft anticipates an additional curve and
>also signature work so I'd like to point out a couple of changes to
>save others having to do so:
>
>1) If no other curves end up being recommended, then the current
>generation process is overly complicated and could well be replaced
>with a description that mirrors how curve25519 was actually chosen:
>i.e. that the minimal sensible A value in Montgomery form be chosen.
>It really depends on how important a generic procedure is seen to be.

It may be that no other curves are recommended *now*. IMHO it would still
make sense to keep the door open for the possible future need.

>2) The procedure for generating base points is currently unused and,
>if change (1) is done, it could be tweaked to reflect how the
>curve25519 base point was generated.

IMHO, it should not be done.

>3) If we don't end up saying anything about signatures, all mention of
>Edwards curves could conceivably be dropped.

Likewise. I’d keep this stuff in.