Re: [Ietf-dkim] Adding an aim= tag to DKIM Signature Tag Specifications

Dave Crocker <dhc@dcrocker.net> Mon, 11 May 2020 17:30 UTC

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To: Alessandro Vesely <vesely@tana.it>
References: <80533fb3-75a2-1d60-801d-c54d735d4094@tana.it>
Cc: ietf-dkim@ietf.org
From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Mon, 11 May 2020 10:30:10 -0700
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Subject: Re: [Ietf-dkim] Adding an aim= tag to DKIM Signature Tag Specifications
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On 5/11/2020 10:21 AM, Alessandro Vesely wrote:
> The question is, what responsibility is being claimed?  
...
> Tagging keys with aim= would allow senders to choose an appropriate selector
> under different circumstances.


If signers want to have a standardized means of indicating the 
fine-grained semantics behind their signature, they can do that without 
modifying DKIM.

Rather, define and use a header field that specifies DKIM signing 
policy.  Cover it with the DKIM signature, of course.

The only interesting part of this task is deciding on a standard set of 
policy labels.

Oh, and then figuring out why and how they are useful to provide...

d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net