Re: [TLS] Analysis of Interop scenarios TLS extension RI w/MCSV
David-Sarah Hopwood <david-sarah@jacaranda.org> Fri, 11 December 2009 03:44 UTC
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Date: Fri, 11 Dec 2009 03:43:49 +0000
From: David-Sarah Hopwood <david-sarah@jacaranda.org>
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Subject: Re: [TLS] Analysis of Interop scenarios TLS extension RI w/MCSV
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Martin Rex wrote: > Michael Gray wrote: >>> in order to reliably provide this, >>> >>> - MCSV is defined to represent an empty TLS extension RI >>> >>> - MSCV MUST be included in *ALL* initial ClientHello handshakes >>> messages _plus_ all renegotiation ClientHellos in backwards >>> interop scenarios (independent of full handshake or session resume). >>> >>> - empty TLS extension RI MUST NOT be sent, ever! >> >> This looks good to me, the only thing I would change is I think MUST NOT >> would be better as SHOULD NOT as the later requires that the implementer >> examine the conditions and implications etc to make the best decision. > > You are right. I'm sorry. I got a little carried away. > > A SHOULD NOT for sending _empty_ TLS extension RI is more appropriate. Why? What is the point of allowing the client to send an empty extension, when a patched client MUST send the MSCV, and a patched server MUST use *only* the MSCV to determine whether the client is patched? You'd just be adding the option to send an extension that has no defined meaning. -- David-Sarah Hopwood ⚥ http://davidsarah.livejournal.com
- [TLS] Analysis of Interop scenarios TLS extension… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Marsh Ray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Michael Gray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Marsh Ray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Dieter Bratko
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Marsh Ray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Nelson B Bolyard
- Re: [TLS] Analysis of Interop scenarios TLS exten… Nelson B Bolyard
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Nelson B Bolyard
- Re: [TLS] Analysis of Interop scenarios TLS exten… David-Sarah Hopwood
- Re: [TLS] Analysis of Interop scenarios TLS exten… Michael Gray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Marsh Ray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… David-Sarah Hopwood
- Re: [TLS] Analysis of Interop scenarios TLS exten… tom.petch
- Re: [TLS] Analysis of Interop scenarios TLS exten… Nelson B Bolyard
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Nelson B Bolyard
- Re: [TLS] Analysis of Interop scenarios TLS exten… Steve Checkoway
- [TLS] Black hole was Re: Analysis of Interop scen… tom.petch
- Re: [TLS] Analysis of Interop scenarios TLS exten… Michael Gray
- Re: [TLS] Analysis of Interop scenarios TLS exten… David-Sarah Hopwood
- Re: [TLS] Analysis of Interop scenarios TLS exten… Michael Gray
- Re: [TLS] Analysis of Interop scenarios TLS exten… Pasi.Eronen
- Re: [TLS] Black hole was Re: Analysis of Interop … Martin Rex
- Re: [TLS] Black hole was Re: Analysis of Interop … Pasi.Eronen
- Re: [TLS] Black hole was Re: Analysis of Interop … Martin Rex
- Re: [TLS] Black hole was Re: Analysis of Interop … Bill Frantz
- Re: [TLS] Analysis of Interop scenarios TLS exten… Martin Rex
- Re: [TLS] Analysis of Interop scenarios TLS exten… Marsh Ray