Re: [TLS] TLS renegotiation issue

Martin Rex <mrex@sap.com> Sat, 07 November 2009 00:27 UTC

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From: Martin Rex <mrex@sap.com>
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To: mike-list@pobox.com (Michael D'Errico)
Date: Sat, 7 Nov 2009 01:28:00 +0100 (MET)
In-Reply-To: <4AF4BD3A.6030507@pobox.com> from "Michael D'Errico" at Nov 6, 9 04:20:10 pm
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Cc: tls@ietf.org
Subject: Re: [TLS] TLS renegotiation issue
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Michael D'Errico wrote:
> 
> Martin Rex wrote:
> > 
> > Eric's proposal to make renegotiation secure does not need any
> > API-level changes, everything is completely internal to the
> > TLS protocol engine.
> 
> Having finished implementing the proposal, I can say that this is
> a true statement.  No API changes were required.

Nico has drawn a raw sketch about SSPI (Microsoft schannel),
and that API will probably require a minor change.
I have not personal experiences with schannel, but from what
Nico described, I think a single new API function and slight
modification of the context iteration functions might
be sufficient (as discussed earlier postings).

CreateRenegoSecurityContext(prev_context, options, &new_context);


-Martin