[Mailman-Users] Rejecting spam at the SMTP level?

[Jim Popovitch]

On Sat, Aug 8, 2015 at 11:43 AM, Jim Popovitch <jimpop at gmail.com> wrote:
> On Wed, Aug 5, 2015 at 3:15 AM, Jayson Smith <jaybird at bluegrasspals.com> wrote:
>>
>> A few months ago I did some Googling and found a project called
>> Mailman-Milter which claims to reject unwanted list mail i.e., nonmember
>> postings at the SMTP level. I would love to use this, but there's virtually
>> no documentation and I've never been able to get it working. Has anyone else
>> had any better luck, or do you know of any other solutions? I'm using
>> Sendmail, by the way.
>
> I'm not exactly sure how to do it in Sendmail (been a long time since
> I've used that) but in Postfix it can be done by setting up a custom
> master.cf service(s) and restriction class(es).
>
> /etc/postfix/master.cf:
>     # Mailman list member checks
>     127.0.0.1:27015 inet    n       n       n       -       1       spawn
>            user=mailman
> argv=/usr/local/lib/mailman/scripts/check_subscriber mylist
>     127.0.0.1:27016 inet    n       n       n       -       1       spawn
>            user=mailman
> argv=/usr/local/lib/mailman/scripts/check_subscriber mylist2
>
> You can get a copy of the check_subscriber script here:
> http://paste.debian.net/plainh/95fd6c08
>
> You then need to setup a restriction class that matches a mailinglist
> posting address and then hooks into the master.cf service on
> 127.0.0.1:27015 listed above.  The restriction class matches just the
> mailinglist posting address (not the -bounce, -owner, -subscribe,
> etc).
>
> /etc/postfix/check_recipients:
> mylist at mydomain.tld             mailman_subscribers_mylist
> mylist2 at mydomain.tld           mailman_subscribers_mylist2
>
> /etc/postfix/main.cf
>     smtpd_client_restrictions=
>         permit_mynetworks,
>         ......
>         check_recipient_access hash:/etc/postfix/check_recipients,
>         permit,
>
>     # declare our custom restriction classes
>     smtpd_restriction_classes =
>         mailman_subscribers_mylist
>         mailman_subscribers_mylist2
>
>    # define our custom restriction class for mylist
>   mailman_subscribers_mylist =
>         check_sender_access tcp:127.0.0.1:27015,
>         permit
>
>    # define our custom restriction class for mylist2
>    mailman_subscribers_mylist2 =
>         check_sender_access tcp:127.0.0.1:27016,
>         permit
>
>
> I would be interested in hearing/learning about how to make that work
> in sendmail if you get the oppty to shoehorn something like this it
> into your setup.
>

BTW, here's what happens as you get older:   you forget that this has
already been documented  :-)

http://bazaar.launchpad.net/~jimpop/mailman/check_subscriber/view/head:/README.check_subscriber

-Jim P.