How to limit ip address range in php, php limit ip range_PHP tutorial

function get_real_ipaddress() {
 if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
  return $_SERVER['HTTP_CLIENT_IP'];
 } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
  return $_SERVER['HTTP_X_FORWARDED_FOR'];
 }
 return $_SERVER['REMOTE_ADDR'];
}
function in_ip_range($ip, $ip_one, $ip_two = false) {
 if(!$ip_two) {
  return $ip_one === $ip;
 }
 return ip2long($ip_one) * -1 >= ip2long($ip) * -1 && ip2long($ip_two) * -1 <= ip2long($ip) * -1;
}
function validate_ip() {
 $ip = explode(':', get_real_ipaddress());
 $ip = $ip[0];
 if(in_ip_range($ip, '212.76.229.115', '212.76.229.120')) {
  return true;
 } else if(in_ip_range($ip, '194.78.4.66', '194.78.4.79')) {
  return true;
 } else if(in_ip_range($ip, '194.8.4.78', '194.8.4.78')) {
  return true;
 } else if(in_ip_range($ip, '0', '1')) { // local
  return true;
 }
 header('Location: http://www.bkjia.com');
}