Re: [Cfrg] I-D Action: draft-irtf-cfrg-hpke-02.txt

Benjamin Kaduk <kaduk@mit.edu> Sat, 07 December 2019 03:11 UTC

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Date: Fri, 6 Dec 2019 19:11:01 -0800
From: Benjamin Kaduk <kaduk@mit.edu>
To: Michael Scott <mike.scott@miracl.com>
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Subject: Re: [Cfrg] I-D Action: draft-irtf-cfrg-hpke-02.txt
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On Wed, Dec 04, 2019 at 11:29:53AM +0000, Michael Scott wrote:
> 
> Some feed-back: It would be a good idea to explicitly warn the reader that
> the X25519/X448 keys are actually in little-endian format, whereas for
> P256/521 they are big-endian.

I think the general idea is that X25519 and X448 APIs act on fixed-length
byte strings and you are not supposed to care about the internal structure
or encoding.  I'm not sure that giving advice of this nature in a document
that solely consumes the algorithms is helpful, with that in mind.

-Ben