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

Nico Williams <nico@cryptonector.com> Wed, 15 April 2015 21:05 UTC

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Date: Wed, 15 Apr 2015 16:05:40 -0500
From: Nico Williams <nico@cryptonector.com>
To: Benjamin Kaduk <kaduk@MIT.EDU>
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Subject: Re: [kitten] WGLC on draft-ietf-kitten-aes-cts-hmac-sha2-06
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On Wed, Apr 15, 2015 at 04:58:08PM -0400, Benjamin Kaduk wrote:
> On Wed, 15 Apr 2015, Nico Williams wrote:
> >  - SHA-256 is used at the 192-bit security level, and the HMAC is
> >    truncated to 192 bits.  The keys for the HMAC are 192 bits at the
> >    192-bit security level.
> >
> >    AES-256 is used at the 192-bit security level because AES-192
> >    implementations are not as universally available as AES-256, or
> >    something.  In any case, I've no objection.
> >
> >    I also do not object to the use of HMAC-SHA256-192 with 192-bit keys
> >    at the 192 bit security level.
> 
> I think that some of these "256" should be "384", unless you have
> progressed from summarizing the document to describing what you would like
> to see...

Yes, sorry.

Nico
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