Subject: [Dcrup] Benjamin Kaduk's Discuss on draft-ietf-dcrup-dkim-crypto-12: (with DISCUSS and COMMENT)

From: Benjamin Kaduk <[email-masked]>
Date: Fri, 15 Jun 2018 11:42:54 -0700

Benjamin Kaduk has entered the following ballot position for
draft-ietf-dcrup-dkim-crypto-12: Discuss

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DISCUSS:
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This is basically pro-forma and should be easy to resolve: as pointed out in the secdir review,
"this is widely used, therefore it must be secure" does  not hold any weight.  The security
considerations should be adjusted to provide some actual justification of the primitive's
security or not make such a claim.

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COMMENT:
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Thanks for writing this document; it will be good to have ed25519 available for DKIM.

In addition to the above DISCUSS point, there were some other good remarks in the secdir
review (though I'm not sure about the "DKIM Hash Algorithms Registry" part) -- it would be
good to see a reply to them as well.

Section 3's Note may want to clarify that it is the public keys that
are 256 bits long (the relevant part, since those are what go in the
DNS).

In Section 4.2:

Typo, "mignt" for "might".
And maybe there's a better way to format the example than with a
selector of just "s"?