Re: [CFRG] misuse-resistant AEAD and HPKE

Dan Harkins <dharkins@lounge.org> Tue, 03 November 2020 07:33 UTC

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Date: Mon, 02 Nov 2020 23:33:46 -0800
From: Dan Harkins <dharkins@lounge.org>
In-reply-to: <84EED12E-6EBB-469F-9FA4-D541D48C3D77@ll.mit.edu>
To: "Blumenthal, Uri - 0553 - MITLL" <uri@ll.mit.edu>
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Subject: Re: [CFRG] misuse-resistant AEAD and HPKE
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   Hi Uri,

On 11/2/20 5:00 PM, Blumenthal, Uri - 0553 - MITLL wrote:
> Would you consider some kind of merge with AES-GCM-SIV? To avoid the 
> need for double-wide key (which, IMHO, is a nuisance)?

   Ultimately it's the will of the group. If there's consensus for 
AES-GCM-SIV
then of course. Also if there's consensus for "don't bother with MRAE" then
it's all moot.

   I prefer AES-SIV over AES-GCM-SIV but for reasons that might not apply
to HPKE. Given that the Expand() can generate any length output, including
double-wide keys, I don't see the nuisance: just set Nk accordingly, there's
actually an existing column for that in table 5 so it's not like this is 
onerous.

   regards,

   Dan.

-- 
"The object of life is not to be on the side of the majority, but to
escape finding oneself in the ranks of the insane." -- Marcus Aurelius