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

Michael D'Errico <mike-list@pobox.com> Thu, 22 January 2015 00:45 UTC

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Date: Wed, 21 Jan 2015 16:45:31 -0800
From: Michael D'Errico <mike-list@pobox.com>
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Subject: Re: [TLS] Last Call: <draft-ietf-tls-downgrade-scsv-03.txt>
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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

Servers wouldn't have to change any logic or close the connection,
the client would make that call.

Mike