Author: Robert Blayzor Date: To: exim-dev Subject: Re: [exim-dev] [Bug 1309] Headers included in dkim_sign_headers are
not in the signature when not in the message
On Sep 23, 2016, at 12:00 PM, Jeremy Harris <jgh@???> wrote: > ... and doesn't say you can't add other things as well, including
> headers not present.
>
> Yes, DKIM breaks mailinglists…
Well, not entirely true. It only breaks if original signed headers are modified. “most” should not be, and dual signing usually isn’t a problem.
But over signing most certainly does break it more. ie: Posting into a mailing list, over signing it with List-Id that doesn’t exist when sending but is added by the list server on the way back out.
>
>> Is there a knob to turn this back to the original functionality and “not oversign” ?
>
> Not a simple knob, no.
> You could construct a non-oversigning list for dkim_sign_headers by
> using a suitably complex expansion. Probably involving ${filter…}.
I guess the “work around” to make them break less would be something like:
