#!/bin/sh
#
# filter.sh
#
# Simple filter to plug Anomy Sanitizer and SpamAssassin
# into the Postfix MTA
#
# From http://advosys.ca/papers/postfix-filtering.html
# Advosys Consulting Inc., Ottawa
#
# For use with:
#    Postfix 20010228 or later
#    Anomy Sanitizer revision 1.49 or later
#    SpamAssassin 2.42 or later
#
# Note: Modify the file locations to match your particular 
#       server and installation of SpamAssassin.

# File locations: 
# (CHANGE AS REQUIRED TO MATCH YOUR SERVER)
INSPECT_DIR=/var/spool/filter
SENDMAIL="/usr/lib/sendmail -i"
ANOMY=/usr/local/anomy
SANITIZER=/usr/local/anomy/bin/sanitizer.pl
ANOMY_CONF=/usr/local/anomy/anomy.conf
ANOMY_LOG=/dev/null
SPAMASSASSIN=/usr/bin/spamassassin

export ANOMY

# Exit codes from <sysexits.h>
EX_TEMPFAIL=75
EX_UNAVAILABLE=69

cd $INSPECT_DIR || { echo $INSPECT_DIR does not exist; exit $EX_TEMPFAIL; }

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

cat | $SPAMASSASSIN -x | $SANITIZER \
   $ANOMY_CONF 2>>$ANOMY_LOG > out.$$ || \
   { echo Message content rejected; exit $EX_UNAVAILABLE; }

$SENDMAIL "$@" < out.$$

exit $?