- `impersonate_service_account` (string) - This allows service account impersonation as per the [docs](https://cloud.google.com/iam/docs/impersonating-service-accounts).
- `image_platform_key` (string) - A key used to establish the trust relationship between the platform owner and the firmware. You may only specify one platform key, and it must be a valid X.509 certificate.
- `image_key_exchange_key` ([]string) - A key used to establish a trust relationship between the firmware and the OS. You may specify multiple comma-separated keys for this value.
- `image_signatures_db` ([]string) - A database of certificates that have been revoked and will cause the system to stop booting if a boot file is signed with one of them. You may specify single or multiple comma-separated values for this value.
- `image_forbidden_signatures_db` ([]string) - A database of certificates that are trusted and can be used to sign boot files. You may specify single or multiple comma-separated values for this value.