Re: [Cfrg] Point format endian (was: Adoption of draft-ladd-spake2 as a RG document)

Alyssa Rowan <akr@akr.io> Mon, 26 January 2015 10:41 UTC

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Date: Mon, 26 Jan 2015 10:41:47 +0000
From: Alyssa Rowan <akr@akr.io>
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Subject: Re: [Cfrg] Point format endian (was: Adoption of draft-ladd-spake2 as a RG document)
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On 26/01/2015 10:20, Peter Gutmann wrote:

> The universal standard for external representations of bignums in 
> IETF protocols is big- endian.

They are NOT bignums. As per TLS WG discussion, all new curves' wire
formats are opaque octet strings.

> Even the PGP and S/MIME, and SSH and TLS, folks have managed to 
> agree on that one.

GnuPG and SSH folks are using 25519's native big-endian formats.

If we try to change it arbitrarily and confusingly, everyone will
ignore CFRG - we're late to the party anyway - and will use the native
format.

- -- 
/akr
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