Subject: [DNSOP] Roman Danyliw's No Objection on draft-ietf-dnsop-server-cookies-04: (with COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Tue, 15 Dec 2020 16:00:43 -0800

Roman Danyliw has entered the following ballot position for
draft-ietf-dnsop-server-cookies-04: No Objection

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COMMENT:
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Thank you to Stephen Farrell for the SECDIR review
(https://mailarchive.ietf.org/arch/msg/secdir/TV4Qw2ionRmJ8skKzgUWzRTeDtw/) and
the discussion around the appropriateness of SipHash, the associated reference
and the arithmetic around the timestamp.   A few comments on this thread
relevant as COMMENTs:

* Please do make clarifying editorial fixes noted here
https://mailarchive.ietf.org/arch/msg/secdir/eGSBMIwkaJjOy9EXtw5lqcgrZRM/

* Thanks for exploring URLs for the normative reference for for SipHash, but
pointing to a personal website is not appropriate (despite it providing a
direct link to the relevant paper).  Please use an authoritative citation in
Section 4.4.  I recommend (something to the effect of):

Aumasson JP., Bernstein D.J. SipHash: A Fast Short-Input PRF. Progress in
Cryptology - INDOCRYPT 2012. Lecture Notes in Computer Science, vol 7668.
Springer.  https://doi.org/10.1007/978-3-642-34931-7_28.

As an aside, while I concur with the sentiment that all crypto algorithms used
in standards track protocols should be reviewed by CRFG
(https://mailarchive.ietf.org/arch/msg/secdir/wZq9M2c3hrd5SpOc1KAM3TuPH0w/) as
a standard practice, this isn’t where we are as a community as of yet.  This
needed review of SipHash can be decoupled from this document. Additionally:

** Please also be clear on the notation that SipHash2.4.  Since the normative
reference uses the notation “SipHash-2-4” (with the dashes), please use that or
provide explicit text to explain it.

** Section 7.  For future agility, should a “recommended” column be
sub-registry just as was added to
https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4
or is the thinking that there will only be serial updates of the cookie
algorithm where concurrent use is not expected?