The mailing list for listmasters using Sympa

[Steve Shipway <address@concealed>]

Sorry, by ‘we’ I meant my site (University of Auckland).  I am not affiliated with the Sympa project other than as having submitted a few patches for consideration.  Apologies if any confusion there.

 

To strip incoming DKIM headers, use something like:

 

remove_headers DKIM-Signature

 

in the list configuration.  This is a comma separated list; this example strips the DKIM header. 

 

If your sender is using SIDF with a badly designed record, or the recipient has a bad SIDF checking implementation,  then the From line gets checked against SPF and fails, though the PRA checks Should use the Sender header (which identifies Sympa) instead of the From line.  In this case you’d need to set the list to anonymise the sender by replacing the From line.

 

Steve

 

Steve Shipway

address@concealed

 

From: address@concealed [mailto:address@concealed] On Behalf Of Erik Olson
Sent: Monday, 7 April 2014 8:36 p.m.
To: address@concealed
Subject: Re: [sympa-users] problems with DMARC?

 

When you say "we", do you mean sympa as a whole, or your site's implementation details?

From what I have read thus far this evening, if the "From:" line is not mangled to remove the original sender "address@concealed", this will cause the reject, because the recipient will check the DMARC records against the From: line.

  - Erik

On 2014-04-07 07:45, Steve Shipway wrote:

If a message has a DMARC header, but is relayed via your list which will change the message, you'll get an invalid DMARC signature and some sites will therefore reject it.

What we do is to strip any incoming DMARC and DKIM headers from messages going to lists using the remove headers option in Sympa.  Then, we add our own DKIM signatures on the way out.

Steve

 

Steve Shipway

University of Auckland ITS

UNIX Systems Design Lead

address@concealed

Ph: +64 9 373 7599 ext 86487

 

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Erik Olson
Proudly joining 21st Century e-mail in 2013

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