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Re: [Cfrg] draft-mcgrew-aead-aes-cbc-hmac-sha2-00: unsafe to optionally hash A's length

David McGrew <mcgrew@cisco.com> Fri, 15 June 2012 16:00 UTC

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From: David McGrew <mcgrew@cisco.com>
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Date: Fri, 15 Jun 2012 12:00:34 -0400
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To: Joachim@Strombergson.com
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Subject: Re: [Cfrg] draft-mcgrew-aead-aes-cbc-hmac-sha2-00: unsafe to optionally hash A's length
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Hi Joachim,

On Jun 14, 2012, at 7:25 AM, Joachim Strömbergson wrote:

> Aloha!
> 
> On 2012-06-13 22:31 , David McGrew wrote:
>> I should add that the test cases are all consistent with this change - they all have MIN_LEN_A = 0.
> 
> Would it make sense to add a TC for when MIN_LEN!=0?

I think it would be best to abandon the option of having a MIN_LEN_A parameter, use David Wagner's suggestion of dealing with cases in which interoperability with existing systems is needed by having a separately defined AEAD algorithm that is not intended for general-purpose use.  

thanks,

David

> 
> Yours
> JoachimS
> 
> -- 
> Med vänlig hälsning, Yours
> 
> Joachim Strömbergson - Alltid i harmonisk svängning.
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