<!-- Code generated from the comments of the GuestAdditionsConfig struct in builder/virtualbox/common/guest_additions_config.go; DO NOT EDIT MANUALLY -->

-   `communicator` (string) - Communicator
-   `guest_additions_mode` (string) - The method by which guest additions are
    made available to the guest for installation. Valid options are upload,
    attach, or disable. If the mode is attach the guest additions ISO will
    be attached as a CD device to the virtual machine. If the mode is upload
    the guest additions ISO will be uploaded to the path specified by
    guest_additions_path. The default value is upload. If disable is used,
    guest additions won't be downloaded, either.
    