Re: review of draft-wierenga-ietf-sasl-saml-00

Simon Josefsson <simon@josefsson.org> Sat, 29 May 2010 09:35 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: Sam Hartman <hartmans-ietf@mit.edu>
Subject: Re: review of draft-wierenga-ietf-sasl-saml-00
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Date: Sat, 29 May 2010 11:34:49 +0200
In-Reply-To: <tslhblsxkq6.fsf@mit.edu> (Sam Hartman's message of "Fri, 28 May 2010 08:40:49 -0400")
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Sam Hartman <hartmans-ietf@mit.edu> writes:

> Simon, I think the IDP may end up involved in the channel binding
> discussion because the client and server may happen not to have another
> mechanism for an integrity protected channel.  In cases where the client
> and server directly share a key or a key falls out of the SAML exchange,
> I agree with you, no IDP interaction is required.

Right.  I think there is some advantage in having a key fall out of a
SAML exchange, but it may also make a SAML SASL mechanism unnecessarily
complex.  I'm concerned that IDPs (and potentially other middle parties)
can see the TLS Finished messages for connections between clients and
servers though.

/Simon