Re: [dmarc-ietf] ARC questions

John Levine <johnl@taugh.com> Sun, 22 November 2020 20:01 UTC

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From: John Levine <johnl@taugh.com>
To: dmarc@ietf.org
Cc: mike@mtcc.com
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Subject: Re: [dmarc-ietf] ARC questions
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In article <bb13f0db-362b-78dd-c005-279ac1776672@mtcc.com> you write:
>-=-=-=-=-=-
>
>
>On 11/22/20 11:18 AM, Douglas E. Foster wrote:
>> ARC has a very limited set of items included in the signature.� �Body 
>> hash is purposefully excluded.� So it is the same signature algorithm 
>> but with different parameters and a different purpose.� Therefore it 
>> has a different header label .
>
>Now wait, Kurt just said that the body hash is included. Somebody has to 
>be wrong here.

Doug is mistaken. The ARC-Message-Signature (AMS) header has the same
body hash as a DKIM signature.