Re: [dmarc-ietf] Call for Adoption: DMARC Use of the RFC5322.Sender Header Field

[Dave Crocker <[e-mail]>]

On 9/29/2020 10:46 AM, Alessandro Vesely wrote:
> On Tue 29/Sep/2020 19:26:21 +0200 Dave Crocker wrote:
>> On 9/29/2020 6:40 AM, Hector Santos wrote:
>>> On 9/27/2020 11:44 PM, Dave Crocker wrote:
>>> DKIM has a single signature binding requirement, the 5322.From
>>>> DMARC establishes the relationship.
>>> I don't read it that way.
>>>
>>> DKIM binds the signer d= domain and the from.domain with no 
>>> enforcement on it nor any indication that they are related when they 
>>> not the same (the missing link). 
>>
>>
>> Absolutely not.  Please re-read the DKIM specification more 
>> carefully. It is quite explicit that it is doing not doing this.
>
>
> I think that by "binding" Hector meant this:
>
> 5.4.  Determine the Header Fields to Sign
>
>    The From header field MUST be signed (that is, included in the "h="
>    tag of the resulting DKIM-Signature header field).
> https://tools.ietf.org/html/rfc6376#section-3.4
>
> The spec doesn't say why, but obviously holds that the From: domain is 
> a specially meaningful one.  There are various other passages, for 
> example:


Sigh,  yes. It has caused this misunderstanding, from the start.

It was imposed on the working group by an IETF Area Director and was 
agreed to as an expedient.

But, sigh, no. It does not carry any of the semantic import being 
claimed in the current discussion.



d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net