sub inblock {
	my($block, $cidr, $target) = @_;
	my $result = 1, $machinebits = (32 - $cidr);
	my $lip1 = unpack("N", pack("c4", split(/\D/, $block,  4)));
	my $lip2 = unpack("N", pack("c4", split(/\D/, $target, 4)));

	$result = 0
		if (($lip1 >> $machinebits) != ($lip2 >> $machinebits));
	return($result);
}