Subject: [trill] Eric Rescorla's No Objection on draft-ietf-trill-over-ip-15: (with COMMENT)

From: Eric Rescorla <[email-masked]>
Date: Sun, 18 Mar 2018 06:49:04 -0700

Eric Rescorla has entered the following ballot position for
draft-ietf-trill-over-ip-15: No Objection

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COMMENT:
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Based on my conversation with DEE, I understand that the HMAC is always
computed over a value which is disjoint with the HKDF-Label. This is not really
cryptographically ideal -- as I stated in my review, you should be HKDFing two
keys off the same key -- but it does imply that the trivial attack doesn't
work, so I'm removing my DISCUSS. As we discussed, please add some explanation
of why this is a non-issue to the document.