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

Tony Arcieri <bascule@gmail.com> Wed, 05 July 2017 23:29 UTC

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From: Tony Arcieri <bascule@gmail.com>
Date: Wed, 5 Jul 2017 16:29:00 -0700
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To: Phillip Hallam-Baker <phill@hallambaker.com>
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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.
>

Ephemeral Montgomery keys, of the sort used by TLS ECDHE, are another
example of a use case which (if proper deployment procedures are followed)
shouldn't be vulnerable to this sort of attack.

I would agree that for long-term static keys, for this and other reasons
perhaps Edwards would be preferable.

-- 
Tony Arcieri