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Re: [Cfrg] Point format for Edwards curves

Nico Williams <nico@cryptonector.com> Mon, 18 May 2015 17:59 UTC

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Date: Mon, 18 May 2015 12:58:58 -0500
From: Nico Williams <nico@cryptonector.com>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [Cfrg] Point format for Edwards curves
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On Mon, May 18, 2015 at 10:48:42AM -0700, Watson Ladd wrote:
> But I'm proposing we solve that right now, rather then adopt a workaround.
> There is no reason not to decide now.

Sure.  I was worried that CFRG might take a long time to reach consensus
on this.

> >
> > For the signature scheme I agree we need a generic point encoding that
> > permits addition, and for that I support your proposal (y plus sign of x).
> 
> That is extra byte for sign bit, little endian?

Yes, little-endian y, sign bit of x as an extra byte.

Nico
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