[TLS] Ed25519 for PKIX

Simon Josefsson <simon@josefsson.org> Tue, 24 September 2013 15:28 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: Rob Stradling <rob.stradling@comodo.com>
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Date: Tue, 24 Sep 2013 17:28:11 +0200
In-Reply-To: <522ED9A7.7080802@comodo.com> (Rob Stradling's message of "Tue, 10 Sep 2013 09:34:47 +0100")
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Cc: Patrick Pelletier <code@funwithsoftware.org>, "tls@ietf.org" <tls@ietf.org>
Subject: [TLS] Ed25519 for PKIX
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Rob Stradling <rob.stradling@comodo.com>; writes:

> Your draft defines a NamedCurve ID for Curve25519, thereby enabling it
> to be used for key exchange.  But what about "(client or server)
> authentication through reference in X.509 certificates..."?
>
> I'm not aware of an equivalent of RFC5639 for Curve25519.  Should we
> create one?  Or could we simply define some new ASN.1 Object
> Identifiers in your draft?

Curve25519 is not directly usable with ECDSA, I believe, so OIDs aren't
sufficient.  Ed25519 is more relevant, however it uses the EdDSA
signature system instead of ECDSA so possibly more of RFC 5480 has to be
duplicated/modified in order for Ed25519 to work.

Given the performance improvements with Ed25519, I think this is a
interesting topic to pursue.  Perhaps a small team of people can get
together and work out what is required.  It doesn't belong in the TLS WG
though.

/Simon