Re: [TLS] SHA-3 in SignatureScheme

Hubert Kario <hkario@redhat.com> Fri, 02 September 2016 11:09 UTC

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From: Hubert Kario <hkario@redhat.com>
To: Ilari Liusvaara <ilariliusvaara@welho.com>
Date: Fri, 02 Sep 2016 13:09:36 +0200
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Subject: Re: [TLS] SHA-3 in SignatureScheme
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On Friday, 2 September 2016 13:42:40 CEST Ilari Liusvaara wrote:
> On Fri, Sep 02, 2016 at 12:08:47PM +0200, Hubert Kario wrote:
> > On Thursday, 1 September 2016 19:22:18 CEST Dave Garrett wrote:
> > > The reason I see is that we currently specify exactly one valid hash
> > > algorithm (in a variety of sizes). The precedent argument is good enough
> > > for me. I think adding it in this document is definitely worth
> > > considering.
> > > I don't want to wait until SHA-2 is considered weak to provide an
> > > alternative, if we can avoid it.
> > 
> > I've created a PR for it: https://github.com/tlswg/tls13-spec/pull/616
> > 
> > I haven't changed any recommendations, the recommended hashes to implement
> > are still SHA-2 based, and I don't think we should change that given that
> > certificates just now are transitioning to SHA-256 because of
> > incompatibility fears.
> 
> Just tweaking the signatures is not enough. There is also the PRF hash,
> and using weak hash there has, umm... rather bad consequences.

SHA-3 ciphersuites added

-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purky┼łova 99/71, 612 45, Brno, Czech Republic