Re: [kitten] CAMMAC open issues

Jeffrey Hutzelman <jhutz@cmu.edu> Mon, 11 November 2013 21:51 UTC

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From: Jeffrey Hutzelman <jhutz@cmu.edu>
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Date: Mon, 11 Nov 2013 16:51:32 -0500
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Subject: Re: [kitten] CAMMAC open issues
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On Thu, 2013-11-07 at 10:56 -0500, Tom Yu wrote:
> Here are what I think are the remaining open issues for CAMMAC.
> 
> Wrapping of CAMMAC:
> 
> Do we recommend enclosing a CAMMAC inside an AD-IF-RELEVANT?  RFC 4120
> says that authorization data are critical, i.e., an implementaiton
> must reject unrecognized authorization data.  Alternatively, we could
> require that CAMMAC be enclosed in an AD-KDCIssued, and drop the
> consequently redundant "svc-verifier" from CAMMAC.

I fail to see how these are alternatives.  As a wrapper, AD-IF-RELEVANT
has special semantics which nullify the criticality of the element it
wraps.  AD-KDCIssued does not have this property.

-- Jeff