Check if an IP address is private

Question

I like to check if an IP address is in a private network. It doesn't work.

My code:

<?php $ip = $_SERVER['REMOTE_ADDR'];  function _isPrivate($ip)  {     $i = explode('.', $ip);      if ($i[0] == 10) {         return true;     } else if ($i[0] == 172 && $i[1] > 15 && $i[1] < 32) {         return true;     } else if ($i[0] == 192 && $i[1] == 168) {         return true;     }     return false; } ?> 

The other one:

<?php $ip = $_SERVER['REMOTE_ADDR'];  function _isPrivate($ip)  {     $ip = ip2long($ip);     $net_a = ip2long('10.255.255.255') >> 24;      $net_b = ip2long('172.31.255.255') >> 20;      $net_c = ip2long('192.168.255.255') >> 16;       return $ip >> 24 === $net_a || $ip >> 20 === $net_b || $ip >> 16 === $net_c;  } ?> 

Any help would be much appreciated, thanks!

Answer 1

I think this should solve the problem.

filter_var used with the following validation rules will return false if the IP address is a private one.

$user_ip = '127.0.0.1'; filter_var(     $user_ip,      FILTER_VALIDATE_IP,      FILTER_FLAG_IPV4 | FILTER_FLAG_NO_PRIV_RANGE |  FILTER_FLAG_NO_RES_RANGE ) 

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