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Re: [TLS] Testing consensus for adding curve25519 to the EC named curve registry

Nick Mathewson <nickm@torproject.org> Mon, 09 September 2013 16:20 UTC

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From: Nick Mathewson <nickm@torproject.org>
To: Douglas Stebila <stebila@qut.edu.au>
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Subject: Re: [TLS] Testing consensus for adding curve25519 to the EC named curve registry
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On Mon, Sep 9, 2013 at 7:12 AM, Douglas Stebila <stebila@qut.edu.au> wrote:
 [...]
> - The curve parameters were generated "verifiably at random", meaning a seed was chosen, and then the curve parameters a and b were generated by hashing the seed a pre-determined number of times using SHA-1.  (Appendix 4 of http://csrc.nist.gov/groups/ST/toolkit/documents/dss/NISTReCur.pdf, or Section 3.1.3.1 of SEC1 http://secg.org, or ANSI X9.62)

A possibly foolish question, but I couldn't find the answer in any of
the documents you listed:

Is it documented how the seeds were chosen?



(In either case, +1 on trying to making curve25519 named. In the FOSS
cryptography world nowadays, I see many more new users of curve25519
than of the NIST curves, because of efficiency and
ease-of-implementation issues.)

yrs,
-- 
Nick Mathewson

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