On 2022-09-29, Johnnie W Adams via Exim-users <exim-users@???> wrote:
> Hi, folks,
>
> We have an unusual mail routing topology, where mail passes through
> our SMTP server, through LISTSERV, and then back through our SMTP server.
>
> We are failing DMARC for reasons I think having to do with when the
> message is signed by DKIM.
>
> I +think+ the issue is that the DKIM signature from our SMTP server is
> from the first pass through and not the second pass. So what I would like
> to do is tell Exim to remove any DKIM signatures from inbound mail. That
> way, when mail leaves our data center, it'll be signed only at the point of
> departure.
>
> Can this be done? It's not obvious from the documentation.
headers can be stripped on arrivial using headers_remove in an ACL
or on delivery using remove_headers in a router or transport
You probablly want to strip the DKIM headers either before delivering
them to the listserver (in the transport) or upon receiving them from
it in an ACL.
--
Jasen.
