Re: [TLS] (selection criteria for crypto primitives) Re: sect571r1

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Tue, 21 July 2015 14:47 UTC

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Date: Tue, 21 Jul 2015 17:47:05 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Johannes Merkle <johannes.merkle@secunet.com>
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Subject: Re: [TLS] (selection criteria for crypto primitives) Re: sect571r1
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On Tue, Jul 21, 2015 at 04:39:17PM +0200, Johannes Merkle wrote:
> 
> I absolutely back up this position. Currently, the TLS 1.3 draft only permits curves over special primes. It has become
> quite clear in the discussions in CFRG and at the NIST ECC workshop that some parties (major hardware manufacturers,
> certification bodies) prefer curves over random primes. And as Rene has pointed out, allowing both would also give more
> agility w.r.t potential future attacks on certain sub-classes.

I thought that Brainpool curves weren't removed (even if those aren't
explicitly in), which are random prime curves.

Also, the security of binary curves seems quite questionable.

And I would expect that if more curves croak, either relatively few
curves croak (in style of MOV or SASS), or almost everything croaks.


-Ilari