Voting

The Note You're Voting On

19 years ago
Below is a merged form of all various notes, and a better (and correct) network matching function.

<?php

function net_match($network, $ip) {
      // determines if a network in the form of 192.168.17.1/16 or
      // 127.0.0.1/255.255.255.255 or 10.0.0.1 matches a given ip
      $ip_arr = explode('/', $network);
      $network_long = ip2long($ip_arr[0]);

      $x = ip2long($ip_arr[1]);
      $mask =  long2ip($x) == $ip_arr[1] ? $x : 0xffffffff << (32 - $ip_arr[1]);
      $ip_long = ip2long($ip);

      // echo ">".$ip_arr[1]."> ".decbin($mask)."\n";
      return ($ip_long & $mask) == ($network_long & $mask);
}

echo net_match('192.168.17.1/16', '192.168.15.1')."\n"; // returns true
echo net_match('127.0.0.1/255.255.255.255', '127.0.0.2')."\n"; // returns false
echo net_match('10.0.0.1', '10.0.0.1')."\n"; // returns true

?>
<< Back to user notes page