Hello,
I run a small publishing company and for the sake of easing
communication between authors (who work in teams) I have provided each
of them with a local alias. Typically, mail sent to
<firstname>.<lastname>@<mydomain> is redirected to
<firstname>.<lastname>@gmail.com, the usual email address of the
author.
You can use a postfix policy service such as postfwd to create a list of
allowed senders for some particular recipient. This isn't difficult,
but will require manual intervention anytime a change is needed.
Postfwd may be kinda old, but is still widely used. http://postfwd.org/
(Reminder: my aim is to allow emails for our site's users only if the
emails come from a certain dynamic list of addresses. It's a tool to
Filter Unauthorized Communications with Keyholes, or in short, let's call
it f.u.c.k.)
I looked at the three solutions hinted at by Noel Jones. Postfwd was
closest to my needs but it seemed more straightforward to use Postfix'
SMTP Access Policy Delegation, which is mentioned in Postfwd's own
documentation. To this end I closely followed the instructions provided by
the documentation:
http://www.postfix.org/SMTPD_POLICY_README.html#client_config
In master.cf I added the lines
# service type private unpriv chroot wakeup maxproc command + args
policy unix - n n - 0 spawn
user=nobody argv=/home/seb/sandra/bin/fuck
(I tried writing this on 1 line or on 2 lines.)
In main.cf I extended smtpd_recipient_restrictions to:
smtpd_recipient_restrictions =
reject_invalid_helo_hostname,
[...]
check_policy_service inet:127.0.0.1:10023,
check_policy_service unix:/home/seb/sandra/bin/fuck,
permit
and, as the doc instructed, I also added:
policy_time_limit = 3600
As for the Perl script that would decide whether an email should go
through or not, for testing purposes I simply wrote:
#!/usr/bin/perl
print "action=dunno\n\n";
I then did a "chmod a+x" on /home/seb/sandra/bin/fuck and a "postfix
reload"; my postfix version is 2.11 (Debian 8).
This setup is as close to the documentation as I can make it. Yet I have
missed something because /var/log/mail.log says:
Nov 7 13:51:17 ns3358511 postfix/smtpd[14177]: warning: connect to
/home/seb/sandra/bin/fuck: No such file or directory
Nov 7 13:51:17 ns3358511 postfix/smtpd[14177]: warning: problem talking
to server /home/seb/sandra/bin/fuck: No such file or directory
although the file really exists:
~>ls -l /home/seb/sandra/bin/fuck
-rwxr-xr-x 1 seb seb 2880 Nov 7 16:31 /home/seb/sandra/bin/fuck
The problem could very well be something simple or so self-evident that it
was not deemed necessary to write it in the documentation.
I toyed with this as much as I dared on a live system, and still have no
clue what the message in mail.log really means.
Any help figuring this out would be very much appreciated, thank you!
Kind regards,
Sébastien.
