Re: [TLS] no_renegotiation alert and SSLV3

Martin Rex <mrex@sap.com> Tue, 22 December 2009 13:57 UTC

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From: Martin Rex <mrex@sap.com>
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To: rdugal@certicom.com
Date: Tue, 22 Dec 2009 14:57:05 +0100
In-Reply-To: <7E1DF37F1F42AB4E877E492C308E6AC402EEF85C@XCH57YKF.rim.net> from "Robert Dugal" at Dec 22, 9 08:09:41 am
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Cc: tls@ietf.org
Subject: Re: [TLS] no_renegotiation alert and SSLV3
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Robert Dugal wrote:
> 
> I am wondering what to do for section 6.2 of
> draft-ietf-tls-renegotiation-02.txt when SSLv3 is negotiated and RI/SCSV
> was not in the ClientHello.   
> 
> The no_renegotiation alert was not defined in SSLv3. 

If you want to abort the handshake, you could send a fatal handshake alert.

I admit to have no relevant implementation experience in that
area, but if your objective is to permit the client to continue
without renegotiation, I would try the pragmatic approach and
send the no_renegotation alert with warning level anyway.

This could work at least for those clients that are merely configured
to use SSLv3 and not _limited_ to SSLv3.

-Martin