[PLUG] exim4 and tcp_wrappers

Jeff Abrahamson <jeff@purple.com> · Sun, 11 Jun 2006 11:35:14 -0400

I want to allow direct smtp to my machine, but only from a limited set
of hosts (who MX for me).  Since exim4 is not linked against libwrap,
I don't expect it to respect /etc/hosts.{deny,allow}, and it turns out
that it doesn't when I try it.

So I put exim4 in inetd.conf:

   smtp   stream    tcp    nowait    uucp    /sbin/exim4 exim4 -bs

I confirm that exim4 is not running, but inetd does start it, as I can
connect to it, but from anywhere I try, not just the special places.

    jeff@astra:etc $ egrep -v '^#' hosts.deny hosts.allow
    hosts.deny:
    hosts.deny:ALL: PARANOID
    hosts.deny:ALL: ALL
    hosts.deny:leafnode: ALL
    hosts.allow:sshd: <deleted for the archives>
    hosts.allow:leafnode: 127.0.0.1
    hosts.allow:
    hosts.allow:exim4: <some fully qualified host names>
    jeff@astra:etc $

I'd just as soon exim4 run as a daemon as it's snappier, but I'd also
like to avoid having my machine hammered by attempted relayers and
such.

Any thoughts on what I'm missing or on how to make this work the way I
want?

-- 
 Jeff

 Jeff Abrahamson  <http://jeff.purple.com/>          +1 215/837-2287
 GPG fingerprint: 1A1A BA95 D082 A558 A276  63C6 16BF 8C4C 0D1D AE4B