Re: [Cfrg] I-D Action: draft-irtf-cfrg-spake2-03.txt

Adam Langley <agl@imperialviolet.org> Sat, 20 February 2016 01:53 UTC

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From: Adam Langley <agl@imperialviolet.org>
To: Alex Elsayed <eternaleye@gmail.com>
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Subject: Re: [Cfrg] I-D Action: draft-irtf-cfrg-spake2-03.txt
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On Fri, Feb 19, 2016 at 4:16 AM, Alex Elsayed <eternaleye@gmail.com> wrote:
> OOI, why not use HKDF, with the string as the IKM? Personally, I'd much
> prefer that to inventing Yet Another Ad-Hoc Way To Extract Arbitrary-
> Length Randomness.

The advantage of iterating SHA-256 is that it's trivial to do,
including in SAGE.

This is only for parameter generation, it's not part of the protocol.
HKDF would be overkill.


Cheers

AGL

-- 
Adam Langley agl@imperialviolet.org https://www.imperialviolet.org