ExtJS VType For Public IP Addresses Complying With RFC 1918

publicip.js

Ext.apply(Ext.form.VTypes, {
  publicip: function(v) {
    var errorMessage = 'Invalid public IP address',
        i,
        parts = [];
    v = Ext.util.Format.trim(v || '').split('.');
    for (i = 0; i < v.length; i++) {
      var num = parseInt(v[i]);
      if (Ext.isNumber(num) && num >= 0 && num <= 255) {
        parts.push(num);
      } else {
        return errorMessage;
      }
    }
    if (parts.length === 4) {
      if (parts[0] === 127 || parts[0] === 10 || (parts[0] === 192 && parts[1] === 168) || (parts[0] === 172 && parts[1] >= 16 && parts[1] <= 31)) { // RFC 1918
        return errorMessage;
      } else {
        return true;
      }
    } else {
      return errorMessage;
    }
  }
});