Dear all,
I was tasked to mark all messages coming from unauthenticated clients
(ie: incoming emails) with a specific subject line.
While subject rewrite is trivial per-se (via header_checks), I am having
big issues rewriting only selected messages. I fully understand that
header_checks only works with single lines, and so I can not set a
if/endif block between multiple lines/conditions.
I was trying to achieve the desired behavior by using two postfix
processes: the first FILTERing external messages, tunneling them to the
second postfix instance to rewrite the subject line. Something as:
- receive all mails on port 25 by the main smtpd process;
- set "smtpd_sender_access=check_sender_access
regexp:/etc/postfix/custom, permit_sasl_authenticated,
permit_mynetworks, reject"
- set /etc/postfix/custom to FILTER non-local emails to another smtpd
process - FILTER custom:localhost:10025
- for the second smtpd process, relax smtpd_sender_access but enable
subject rewrite -
smtpd_sender_access=regexp:/etc/postfix/rewrite_headers
...but it does not work. I have some issues grasping how to configure
the second postfix process via master.cf. I tried something as:
localhost:10025 inet n - n - - smtpd
-o smtpd_sender_access=regexp:/etc/postfix/rewrite_headers
but withtout success.
I already read http://www.postfix.org/FILTER_README.html and
http://www.postfix.org/SMTPD_PROXY_README.html, but I am not sure how to
proceed further.
So I would ask if what I am trying to do is at all possible with plain
postfix (ie: without mimedefang or similar milter, as I am already using
rspamd for spam filtering) and, if so, how to configure master.cf and
the FILTER rule.
Thanks.
--
Danti Gionatan
Supporto Tecnico
Assyoma S.r.l. - www.assyoma.it
email: g.da...@assyoma.it - i...@assyoma.it
GPG public key ID: FF5F32A8
