How to block all internet traffic from China

The Perl module IP::China provides a way to block all web accesses from China using a Perl script. Here is an example CGI script which demonstrates sending a "forbidden" response if the remote user address is from China.

#!/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.
    }
}

Download it here.

You can test it by running it with a Chinese internet address:

REMOTE_ADDR=182.118.20.173 perl block-china.pl

It will print out

Content-Type: text/plain
Status: 403

Sorry!

At the Github repository there is a version in C as well. This Perl module is based on GeoLite Free Downloadable Databases.

Web links

Stop Traffic From China IP Address Blocks To Protect Your Web Server From Chinese Hackers
This provides an alternative method, based on the use of server configuration files for the Apache web server.
"Relatively easy way to block all traffic from a specific country?" at Serverfault.com
Contains some advice.
On blocking Chinese IP addresses
An article from 2005 describing some of the problems.

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