#!/usr/bin/perl
# check for black holes

use Socket;

open(IN, "formail -c -x received:|") || die "Cant open input";
close(STDIN);
while (<IN>) {
  m/[[]([0-9.]+)[]]/ && push @hosts, $1;
}
# we have now hosts at @hosts
# $host[0] = where we receive
# $host[$#host] = original sender

for ($i = 0; $i <= $#hosts; $i++) {
  @ia = split(/\./, $hosts[$i]);
  $iaddr = pack('C4', @ia);
  $name = gethostbyaddr ($iaddr, AF_INET);
  printf "%d: %s [%s]\n", $i,$name?$name:"unknown",$hosts[$i];
  if (gethostbyname(sprintf("%d.%d.%d.%d.rbl.maps.vix.com", 
			    $ia[3],$ia[2], $ia[1], $ia[0]))) {
    printf "\t%s [%s] IN RBL\n", $name?$name:"unknown",$hosts[$i];
    exit (1);
  } 
  if (gethostbyname(sprintf("%d.%d.%d.%d.relays.mail-abuse.org", 
			    $ia[3],$ia[2], $ia[1], $ia[0]))) {
    printf "\t%s [%s] IN RSS\n", $name?$name:"unknown",$hosts[$i];
    exit (1);
  }
  if ($i < $#hosts && # not the first host
      $i < 2 && # no hut.fi || iki.fi
      gethostbyname(sprintf("%d.%d.%d.%d.dul.mail-abuse.org", 
			    $ia[3],$ia[2], $ia[1], $ia[0]))) {
    printf "\t%s [%s] IN DUL\n", $name?$name:"unknown",$hosts[$i];
    exit (1);
  }
}
exit(0);