Re: [TLS] TLS renegotiation issue

Nicolas Williams <Nicolas.Williams@sun.com> Fri, 06 November 2009 00:40 UTC

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Date: Thu, 5 Nov 2009 18:29:28 -0600
From: Nicolas Williams <Nicolas.Williams@sun.com>
To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] TLS renegotiation issue
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Note, there's a way to implement Eric's proposal as-is and in an
SSPI/GGF-GSS-API way that doesn't suck, but which does require a
layering violation, though one that I could live with:

 - client and server apps both extract the 'tls-unique-for-telnet'
   channel binding from the outer connection, prefix that with the
   RFC5056-required prefix, and pass that to the init/accept_sec_context
   functions.

 - The TLS init/accept_sec_context implementation checks to see if the
   channel binding input starts with "tls-unique-for-telnet:" (the
   RFC5056-required prefix when using that channel binding type), and,
   if it does, then split the rest of the channel binding input
   accordingly and use the two halfs as per-Eric's proposal.

I can live with that.  I'd like to have a generic channel binding
facility in TLS.  I'd like to not have to implement such a layering
violation.

Nico
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