code: func validateIPWhitelist(wl *protocol.AuthIPWhitelist) error {
  	for _, subnet := range wl.GetSubnets() {
  		if _, _, err := net.ParseCIDR(subnet); err != nil {
  			return fmt.Errorf("bad subnet %q - %s", subnet, err)
  		}
  	}
  	return nil
  }
docs: // validateIPWhitelist checks IPs in the whitelist are parsable.