Re: [dmarc-ietf] Implementing psddmarc

Alessandro Vesely <> Fri, 27 September 2019 11:20 UTC

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From: Alessandro Vesely <>
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Date: Fri, 27 Sep 2019 13:19:59 +0200
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Subject: Re: [dmarc-ietf] Implementing psddmarc
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On Wed 25/Sep/2019 23:23:04 +0200 Scott Kitterman wrote:
> On Tuesday, September 24, 2019 10:16:08 AM EDT Alessandro Vesely wrote:
>> Hi all,
>> I added psddmarc to the latest zdkimfilter.
>> After some thought, I chose to use and distribute a file like the one
>> attached.  Two reasons for doing so are as follows:
>> 1. Avoid to invent yet another file format, specifying header line, initial
>> dot, comments, and the like.
>> 2. Reuse the library calls already available for parsing and searching the
>> PSL.
>> On the second call, the software passes the organizational domain resulting
>> from the first call, and thus retrieves the "super organizational" domain,
>> if any.  The file only contains the domain from registry which
>> actually sports a DMARC record.  While the experiment is ongoing, the file
>> will have to be updated.
>> It would be convenient, if more implementations will find the above reasons
>> convincing, if such a list would be maintained and distributed by
>> along with (or instead of) the csv format.  After all, since
>> this list extends the PSL, keeping the same format may make some sense.
> I think we should include this in the options for the experiment about how to 
> keep track of which PSDs are doing PSD DMARC.
> Can you provide what you'd like me to add about your implementation for 
> Appendix C?

If needed, a short characterization can be as follows:

    The zdkimfilter module is a separately available add-on to

    Mostly used for DKIM signing, it can be configured to also
    verify, apply DMARC policies, and send aggregate reports.