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Re: [Cfrg] Side channel attack and Edwards curves...

Tony Arcieri <bascule@gmail.com> Thu, 06 July 2017 00:07 UTC

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From: Tony Arcieri <bascule@gmail.com>
Date: Wed, 05 Jul 2017 17:07:01 -0700
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To: Phillip Hallam-Baker <phill@hallambaker.com>
Cc: "cfrg@irtf.org" <cfrg@irtf.org>
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Subject: Re: [Cfrg] Side channel attack and Edwards curves...
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On Wed, Jul 5, 2017 at 4:16 PM, Phillip Hallam-Baker <phill@hallambaker.com>
wrote:

> ​You can blind in either. But if you are going to blind then a lot of the
> advantages of Montgomery start to collapse. because you have to do that add
> stage.
>

What if you blinded kP with r using:

    r*([k r^-1]*P)

which only requires inversions?

-- 
Tony Arcieri

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