Re: road warrior trying to simplify a mail setup

[kai.grossjohann@uni-duisburg.de (Kai Großjohann)]

Michel Schinz <Michel.Schinz@epfl.ch> writes:

> The major one is mail splitting. Gnus, Mail.app and IMP all have ways
> to sort mail, but of course they are not compatible. Which means that
> you either have to install an IMAP server with server-side splitting,
> or have to find another way. I didn't experiment with server-side
> splitting, but I fear that the solutions available now (i.e. SIEVE)
> are not powerful enough to filter SPAM using external tools
> (SpamAssassin or whatever).

I'm not a SpamAssassin poweruser (in fact, I just installed it and
then forgot about it until a few seconds ago), but my setup works
nicely with this: incoming mail is passed by Postfix through SA,
before ending up in the Cyrus server.  There, Sieve can be used to
split based on the headers added by SA.

I didn't know what I was doing, so I'm rather surprised it works.

In /etc/postfix/master.cf, augment the smtp line as follows:

smtp      inet  n       -       -       -       -       smtpd
        -o content_filter=filter:

And also add a filter line (okay, two lines), like this:

filter  unix    -       n       n       -       -       pipe
        flags=Rq user=spamassassin argv=/etc/postfix/spamassassin.sh -f ${sender} -- ${recipient}

Hm.  I'm not sure if the script does the right thing.  It seems it
should just frob the headers and dump the message to standard out.
But it invokes sendmail.  Hm.  I got the script from some readme or
other, or maybe from the web:

#!/bin/sh
INSPECT_DIR=/var/spool/spamassassin
SENDMAIL="/usr/sbin/sendmail -i"

# Exit codes (snarfed from sysexists.h)
EX_TEMPFAIL=75
EX_UNAVAILABLE=69

# Clean up when done or when aborting.
trap "rm -f in.$$ out.$$" 0 1 2 3 15

# Start processing.
cd $INSPECT_DIR || { echo $INSPECT_DIR does not exist; exit $EX_TEMPFAIL; }

cat >in.$$ || { echo Cannot save mail to file; exit $EX_TEMPFAIL; }

#( echo "X-Filtered: yes" ; cat in.$$ ) > out.$$ || \
#       { echo Filter failure; exit $EX_UNAVAILABLE; }
/usr/bin/spamc -f <in.$$ >out.$$ || \
    { echo Message content rejected; exit $EX_UNAVAILABLE; }

$SENDMAIL "$@" <out.$$

exit $?
-- 
A turnip curses Elvis