Re: [Cfrg] Point format endian

Alyssa Rowan <akr@akr.io> Sun, 25 January 2015 21:12 UTC

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Date: Sun, 25 Jan 2015 21:12:10 +0000
From: Alyssa Rowan <akr@akr.io>
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Subject: Re: [Cfrg] Point format endian
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On 24/01/2015 16:18, Salz, Rich wrote:

>> [DH] So a long-standing tradition of the on-the-wire format is
>> changed because of the way the first curve25519 library was
>> written? That's a weak justification.

So all the running code in every X25519 library out there (there are
several) should change its on-the-wire format because of the way some
other earlier wire protocols (with explicitly no relation to this one,
as Rich mentions) were written? ¬_¬

> [RS] The IETF should follow its tradition and drop its wire format
> tradition.

Agreed. To the extent it matters, there's no justification for
changing the X25519 wire format to big-endian at all; it'd just be
gratuitous incompatibility with existing libraries for no reason if we
did. I might not put it quite as sarcastically as djb, but I am not a
fan of that. Running code wins: and that's little-endian.

- -- 
/akr
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