Re: DSpam Content Filter via Header_Checks

On Thursday, May 05, 2005 at 11:12 CEST,
Jens Mittag <jens.mittag@prime23.de> wrote:

> I have a problem with header_checks and applying FILTER rules,
> depending on the header of the e-mail.
> At the moment, I am using content_filter on the smtp transport as
> specified in master.cf:
>=20
> ## master.cf:
> smtp inet n - - - - smtpd -o content_filter=3Ddspam:
> dspam unix - n n - 10 pipe
> flags=3DRu user=3Dvmail argv=3D/usr/local/bin/dspam --deliver=3Dinnoc=
ent=20
> --user ${recipient} -i -f $sender -- $recipient
>=20
> DSpam checks the mail and sends it back to postfix via sendmail. That
> works fine, but has the disadvantage, that every outgoing mail is
> checked too. I would like to have only incoming mail for my local
> domains get checked.

http://www.postfix.org/FILTER_README.html#remote_only

> I thought, let's decide that in the header_checks... to prevent "too
> many hops", I first check if the mails was already scanned by DSpam
> (X-DSPAM-Result Header) and if not, check if the mail is for my local
> domains and whether or not, send it through DSpam.
>=20
> ## main.cf
> header_checks =3D pcre:/etc/postfix/header_checks
>=20
> ## /etc/postfix/header_checks (version 1)
> if !/^X-DSPAM-Result/
> /for <.*@(domain1.tld|domain2.tld|domain3.tld)>/ FILTER dspam:
> endif

That's not how header_checks works. One line is inspected at a time.
The above means "if this line does not match /^X-DSPAM-Result/ and
THE SAME LINE matches /for <.*@(domain1.tld|domain2.tld|domain3.tld)>/
then apply the FILTER action".

There is no need to use something that complex. Example:

smtpd_client_restrictions =3D
check_client_access cidr:/path/to/file

/path/to/file:
# Your local subnet(s)
1.2.3.0/24 OK

# A catch-all for the rest
0.0.0.0/0 FILTER dspam:

[...]

--=20
Magnus B=E4ck
magnus@dsek.lth.se