Re: [Gen-art] Gen-ART Review of draft-ietf-kitten-pkinit-freshness-07

Jari Arkko <jari.arkko@piuha.net> Thu, 01 December 2016 09:35 UTC

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From: Jari Arkko <jari.arkko@piuha.net>
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Date: Thu, 1 Dec 2016 11:30:29 +0200
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Cc: "Paul Miller \(NT\)" <paumil@microsoft.com>, Michiko Short <michikos@microsoft.com>, IETF Gen-ART <gen-art@ietf.org>, "draft-ietf-kitten-pkinit-freshness.all@ietf.org" <draft-ietf-kitten-pkinit-freshness.all@ietf.org>
Subject: Re: [Gen-art] Gen-ART Review of draft-ietf-kitten-pkinit-freshness-07
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Many thanks for your review, Russ, and for thinking about this space and what issues there might be.

I too am concerned about the issue that Russ Housley raised: bad practices in creating the freshness tokens creates a security issue. If this cannot be handled in the way that Russ initially suggested (setting a minimum number of bits) then a proper discussion of the issue and recommendations to avoid the problems need to be included in the security considerations section.

I fully recognise the point from the authors that different styles of creating the tokens result in different implications, and that setting a mere minimum number of bits may not be appropriate.

Jari