code: func (e *Entry) checkIPandProtocol(set *IPSet) bool {
  	// set default protocol to tcp if empty
  	if len(e.Protocol) == 0 {
  		e.Protocol = ProtocolTCP
  	} else if !validateProtocol(e.Protocol) {
  		return false
  	}
  
  	if net.ParseIP(e.IP) == nil {
  		klog.Errorf("Error parsing entry %v ip address %v for ipset %v", e, e.IP, set)
  		return false
  	}
  
  	return true
  }
docs: // checkIPandProtocol checks if IP and Protocol of Entry is valid.