Javascript / JQuery for testing if a given IP is in the IANA reserved range

example.js

alert( is_iana_reserved_ip("192.168.5.5") );
alert( is_iana_reserved_ip("192.200.5.5") );

is_iana_reserved_ip.js

  function IPnumber(IPaddress) {
    var ip = IPaddress.match(/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/);
    if(ip) {
        return (+ip[1]<<24) + (+ip[2]<<16) + (+ip[3]<<8) + (+ip[4]);
    }
    // else ... ?
    return null;
  }

  function IPmask(maskSize) {
      return -1<<(32-maskSize)
  }

  function is_iana_reserved_ip(ip){
    // "ip": maskbits
    // per http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml
    var reserved = {
      "0.0.0.0": 8, 
      "10.0.0.0": 8, 
      "100.64.0.0": 10, 
      "127.0.0.0": 8, 
      "169.254.0.0": 16,
      "172.16.0.0": 12, 
      "192.0.0.0": 24, 
      "192.0.2.0": 24,  
      "192.88.99.0": 24, 
      "192.168.0.0": 16, 
      "198.18.0.0": 15, 
      "198.51.100.0": 24, 
      "203.0.113.0": 24,  
      "224.0.0.0": 8, 
      "225.0.0.0": 8, 
      "226.0.0.0": 8, 
      "227.0.0.0": 8, 
      "228.0.0.0": 8, 
      "229.0.0.0": 8, 
      "230.0.0.0": 8, 
      "231.0.0.0": 8, 
      "232.0.0.0": 8, 
      "233.0.0.0": 8, 
      "234.0.0.0": 8, 
      "235.0.0.0": 8, 
      "236.0.0.0": 8, 
      "237.0.0.0": 8, 
      "238.0.0.0": 8, 
      "239.0.0.0": 8, 
      "255.255.255.255": 32, 
    };

    var results = $.map(reserved, function(m, i){ 
      return (IPnumber(i) & IPmask(m)) == (IPnumber(ip) & IPmask(m)); 
    });

    if( results.indexOf(true) > -1){
      return true;
    }
    else {
      return false;
    }
  }