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Re: [TLS] Last Call: <draft-ietf-tls-downgrade-scsv-03.txt>

Hubert Kario <hkario@redhat.com> Thu, 22 January 2015 11:07 UTC

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From: Hubert Kario <hkario@redhat.com>
To: tls@ietf.org
Date: Thu, 22 Jan 2015 12:07:08 +0100
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Subject: Re: [TLS] Last Call: <draft-ietf-tls-downgrade-scsv-03.txt>
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On Wednesday 21 January 2015 16:45:31 Michael D'Errico wrote:
> Martin Rex wrote:
> > Rubber-Stamping the fallback-scsv hack onto the standards track is
> > IMHO a very bad idea.
> 
> I apologize if this has been discussed before (I have about 1400
> unread TLS mailing list messages in my queue), but it seems that
> a simpler SCSV or extension could just ask the server to echo its
> highest supported version:
> 
>      ClientHello w/SCSV    ----->
>                            <-----    ServerHello w/version extension

that's not allowed by the RFC's, the server can send back only the extension 
id's client has sent

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

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