Re: [TLS] Last Call: <draft-ietf-tls-ssl2-must-not-03.txt> (Prohibiting SSL Version 2.0) to Proposed Standard

Michael D'Errico <mike-list@pobox.com> Thu, 02 December 2010 05:48 UTC

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Date: Wed, 01 Dec 2010 21:49:49 -0800
From: Michael D'Errico <mike-list@pobox.com>
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To: Matt McCutchen <matt@mattmccutchen.net>
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Cc: Glen Zorn <gwz@net-zen.net>, tls@ietf.org
Subject: Re: [TLS] Last Call: <draft-ietf-tls-ssl2-must-not-03.txt> (Prohibiting SSL Version 2.0) to Proposed Standard
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Matt McCutchen wrote:
> On Wed, 2010-12-01 at 21:01 -0800, Michael D'Errico wrote:
>> The reason it is OK to accept CLIENT-HELLO is because it can carry the SCSV
>> cipher suite value used to plug the renegotiation security hole (RFC 5746).
> 
> Why is that relevant?  The draft only retires SSL 2.0, for reasons
> unrelated to the renegotiation issue.

If you couldn't put the SCSV into the CLIENT-HELLO, then it would not
be OK for servers to accept that message; it would have to be a MUST
NOT.

Mike