Re: [kitten] WGLC on draft-ietf-kitten-aes-cts-hmac-sha2-06

[Jeffrey Altman <[e-mail]>]

On 4/17/2015 5:23 PM, Benjamin Kaduk wrote:
> We got a number of comments and questions in this last call.  I will try
> to summarize them and the response to them, below.  Please let me know if
> I have missed something or inaccurately represented someone's statements.


> * Jeff A. asked if we have independent cryptographic review
> 
> Nico and I claim that we are using well-understood building blocks in
> well-understood ways, and no additional review is needed.  Jeff A. has not
> had a chance to reply to these claims yet.

I am happy with the current level of review activity.

> 
> * Jeff A. cares strongly about interoperability and test vector
> verification.
> 
> Greg and Weijun have published python and java code respectively, which
> verify the test vectors, but are not quite enough for interoperability
> testing (?).  The authors had java and python implementations to verify
> the test vectors, which are not (?) published.  I claim this is sufficient
> for now, and Jeff A. has not had a chance to reply yet.

I care enough about interoperability that I have agreed to fund an
implementation for Heimdal.  I would like to see someone commit to a
second implementation.

> * Michael plans to update the draft in response to comments, and expand
> the test vectors.
> 
> There is much rejoicing.

Thank you.

> =======================================================
> 
> That seems to leave us with the following action items:
> 
> For the document editor:
> * remove truncation from the PRF output and use the natural hash output
> length
> * remove the use of random-to-key() and discussion of constant values from
> section 3
> * add an output length argument to KDF-HMAC-SHA2() and adjust text
> accordingly
> * update test vectors to include base keys and key usage values for all
> test cases
> * reword the text discussing aes256 with 192-bit keys
> 
> For Jeffrey Altman:
> * comment about the status of the crypto review and the interoperability
> testing in light of other comments that have come in on those points.

Done.