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How to Redirect Visitors based on IP Location

Tags: location based redirectionredirectionredirection based on country

Scenario:

Location Based Redirection

Location based redirection is a technique that is useful when you want to redirect traffic to your website to different parts of your websites or to your sub-domains based on the visitor’s geographic location. Let us see how to redirect visitors based on IP location

The redirection method I am using here is done with the help of 2 files,i.e, a PHP script file and a text file.

Text File:

The text file contains the IP ranges that is specific to a country. For example, the text file containing the IP ranges specific to Germany looks like the following. This is just representative data, you need to get the actual ones for the proper functioning of the script

2.16.6.0/23
2.16.12.0/23
2.16.22.0/23
2.16.24.0/23
2.16.28.0/22
2.16.32.0/23
2.16.36.0/23
2.16.46.0/23
2.16.48.0/23
2.16.61.0/24
2.16.62.0/24
2.16.64.0/24

PHP Script:

The PHP script is used to fetch the list of IPs from these CIDR ranges and redirect the user based on their IP. The script is given below.

<?php
function checkUserIP($user_ip, $cidrs) {      // Function to get IP list from range
    $ipu = explode('.', $user_ip);
    foreach ($ipu as &$v)
    $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
    $ipu = join('', $ipu);
    $res = false;
    foreach ($cidrs as $cidr) {
                $parts = explode('/', $cidr);
                $ipc = explode('.', $parts[0]);
                foreach ($ipc as &$v)
                $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
                $ipc = substr(join('', $ipc), 0, $parts[1]);
                $ipux = substr($ipu, 0, $parts[1]);
                $res = ($ipc === $ipux);
                if ($res) break;
    }
  return $res;
}
 
 
$user_ip = $_SERVER['REMOTE_ADDR']; // get user ip
 
// Don't change the above part
 
 
// Custom code suited to your setup.
 
$f1 = 'ip.txt';  // Text file with IP ranges.
 
if (checkUserIP($user_ip, file($f1, FILE_IGNORE_NEW_LINES))) {  // Compare user IP with the IP list from text file.
 header("Location: <location>");   // Specify the location to which to redirect to.
}

The above script will compare the user’s IP with the IP ranges in the text file ‘ip.txt’ and performs redirection based on the output.

How it works?

I am going to show an example of a situation which uses the above script to redirect users based on their country.

For testing purpose, I have created a simple website iptestsite.cf. It has an index file for the main site and there are two directories ‘de’ and ‘fr’.

The following are the contents of the public_html directory.

[/home/u538987939/public_html/] ls -l
drwxr-xr-x 2 u538987939 u538987939   4096 Mar 23 02:20 de         
-rw-r--r-- 1 u538987939 u538987939 883690 Mar 23 01:52 deip.txt
drwxr-xr-x 2 u538987939 u538987939   4096 Mar 23 02:27 fr
-rw-r--r-- 1 u538987939 u538987939 468112 Mar 23 01:51 frip.txt
-rw-r--r-- 1 u538987939 u538987939     37 Mar 23 01:41 index.php

-rw-r--r-- 1 u538987939 u538987939   1009 Mar 23 02:16 ip.php   

I am going to redirect the visitors from Germany to the directory ‘de‘ and visitors from France to the directory ‘fr‘ and everyone else to public_html/index.php.

The public_html/index.php file contains the following contents.

<?php require("ip.php"); // The index.php will only work after the execution of ip.php
?>    
Home Page

The ‘ip.php’ file contains the PHP script mentioned earlier modified to suit our current purpose.

<?php
function checkUserIP($user_ip, $cidrs) {
    $ipu = explode('.', $user_ip);
    foreach ($ipu as &$v)
    $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
    $ipu = join('', $ipu);
    $res = false;
    foreach ($cidrs as $cidr) {
                $parts = explode('/', $cidr);
                $ipc = explode('.', $parts[0]);
                foreach ($ipc as &$v)
                $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
                $ipc = substr(join('', $ipc), 0, $parts[1]);
                $ipux = substr($ipu, 0, $parts[1]);
                $res = ($ipc === $ipux);
                if ($res) break;
    }
  return $res;
}
 
$f1 = 'frip.txt';        // File that contains IP ranges specific to France.
$f2 = 'deip.txt';        // File that contains IP ranges specific to Germany.
$user_ip = $_SERVER['REMOTE_ADDR']; // get user ip
// checking user ip address redirect
 
if (checkUserIP($user_ip, file($f1, FILE_IGNORE_NEW_LINES))) {
 header("Location: http://iptestsite.cf/fr");  // Redirect to 'fr' if user IP belongs to frip.txt
}
 
elseif (checkUserIP($user_ip, file($f2, FILE_IGNORE_NEW_LINES))) {
 header("Location: http://iptestsite.cf/de");  // Redirect to 'de' if user IP belongs to deip.txt
}
?>

The ‘frip.txt’ contains IP ranges specific to France and ‘deip.txt’ contains IP ranges specific to Germany in the format mentioned earlier. You can get the IP ranges list from the URL http://www.ip2location.com/blockvisitorsbycountry.aspx. From there select the country and choose output format as CIDR.

Here are the contents of the directories ‘de’ and ‘fr’.

$[/home/u538987939/public_html/] ls-l de
total 8
-rw-r--r-- 1 u538987939 u538987939 877 Mar 23 02:23 deip.php
-rw-r--r-- 1 u538987939 u538987939  38 Mar 23 02:25 index.php
u538987939$ [/home/u538987939/public_html/] ls-l fr
total 8
-rw-r--r-- 1 u538987939 u538987939 877 Mar 23 02:27 frip.php

-rw-r--r-- 1 u538987939 u538987939  38 Mar 23 02:26 index.php

The public_html/de/index.php file contains the following.

<?php require("deip.php"); 
?>
DE Home

The ‘public_html/de/deip.php‘ file is used to redirect the IPs that does not belong to Germany to main site.

<?php
function checkUserIP($user_ip, $cidrs) {
    $ipu = explode('.', $user_ip);
    foreach ($ipu as &$v)
    $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
    $ipu = join('', $ipu);
    $res = false;
    foreach ($cidrs as $cidr) {
                $parts = explode('/', $cidr);
                $ipc = explode('.', $parts[0]);
                foreach ($ipc as &$v)
                $v = str_pad(decbin($v), 8, '0', STR_PAD_LEFT);
 
                $ipc = substr(join('', $ipc), 0, $parts[1]);
                $ipux = substr($ipu, 0, $parts[1]);
                $res = ($ipc === $ipux);
                if ($res) break;
    }
  return $res;
}
 
 
$f1 = '../deip.txt';
 
 
$user_ip = $_SERVER['REMOTE_ADDR']; // get user ip
 
// checking user ip address redirect
 
 
if (!checkUserIP($user_ip, file($f1, FILE_IGNORE_NEW_LINES))) { 
 header("Location: http://iptestsite.cf"); // Redirect IPs that does not belong to Germany to main site.
}
 
?>

The directory ‘fr’ uses a similar setup to redirect the IPs that does not belong to France to main site.

Testing:

For testing the site from multiple locations, I am going to use http://www.locabrowser.com/. I am going to test the website from France, Germany, US, Singapore.

First we will access the main site ( http://iptestsite.cf ) from these locations.

We get the following outputs.

As you can see, the IP from Germany is being redirected to ‘de’ and the IP from France ‘fr’.

Now we will try accessing one of the subdirectories ( http://iptestsite.cf/fr ) directly from these locations.

We get the following output.

As you can see, the output looks same as before. What happened was, the IPs that does not belong to France was redirected to the main website. From there, the IP that belongs to Germany was again redirected to ‘de’.

Category : Linux