Subject: [Curdle] Adam Roach's No Objection on draft-ietf-curdle-rsa-sha2-11: (with COMMENT)

From: Adam Roach <[email-masked]>
Date: Tue, 10 Oct 2017 15:56:24 -0700

Adam Roach has entered the following ballot position for
draft-ietf-curdle-rsa-sha2-11: No Objection

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COMMENT:
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Section 3.2:
  The signature field, if present, encodes a signature using an
  algorithm name that MUST match the SSH authentication request - either
  "rsa-sha2-256", or "rsa-sha2-512".

It might be that I'm not familiar enough with SSH to know what recipients do
when receiving unexpected values and the the proper behavior here would be
obvious to implementors. If that's not the case, I would think that additional
text here telling recipients what to do in the case of a mismatch would be
helpful.

The reference [EXT-INFO] needs to be normative rather than informative, as it
is part of a normative behavior described in this document.

Both section 1 and Section 5.1 describe NIST recommendations regarding key
length, while not endorsing them (normatively or otherwise). This strikes me as
notable, given that the NIST recommendations regarding SHA-1 seem to form part
of the rationale for its replacement. Is the lack of endorsing NIST-recommended
key lengths intentional?

Nits:

RFC6979 is in the references section, but does not appear to be referenced.

One of the lines in the Acknowledgements section is too long.