#!/usr/bin/perl
use warnings;
use strict;
use IP::China 'chinese_ip';

my $remote_addr = $ENV{REMOTE_ADDR};
if ($remote_addr) {
    if (chinese_ip ($remote_addr)) {
        print <<EOF;
Content-Type: text/plain
Status: 403

Sorry!
EOF
        exit;
    }
    else {
        # Provide another response.
    }
}