sub filter {
  my $data = shift;
  open(FH, "filter") or die $!;
  my @words = <FH>;
  foreach my $word (@words) {
    #chomp $word;
    $word =~ s/\r//;
    $word =~ s/\n//;
    error('bad word found') if ($data =~ /$word/i);
  }
  return $data;
}