microdroid_manager/src/vm_config.cddl

; Configuration Descriptor used in the DICE node that describes the payload of a Microdroid virtual
; machine.
;
; See the Open DICE specification
; https://pigweed.googlesource.com/open-dice/+/HEAD/docs/specification.md,
; and the Android Profile for DICE
; https://pigweed.googlesource.com/open-dice/+/HEAD/docs/android.md.
;
; CDDL for the normal Configuration Descriptor can be found at
; https://cs.android.com/android/platform/superproject/main/+/main:hardware/interfaces/security/rkp/aidl/android/hardware/security/keymint/generateCertificateRequestV2.cddl

; The configuration descriptor node for a Microdroid VM, with extensions to describe the contents
; of the VM payload.
; The subcomponents describe the APKs and then the APEXes that are part of the VM. The main APK
; is first, followed by any extra APKs in the order they are specified in the VM config.
; The APEXes are listed in the order specified when the VM is created, which is normally alphabetic
; order by name.
VmConfigDescriptor = {
    -70002 : "Microdroid payload",      ; Component name
    (? -71000: tstr //                  ; Path to the payload config file
    ? -71001: PayloadConfig),
    ? -71002: [+ SubcomponentDescriptor],
}

PayloadConfig = {
    1: tstr                             ; Path to the binary file where payload execution starts
}

; Describes a unit of code (e.g. an APK or an APEX) present inside the VM.
;
; For an APK, the fields are as follows:
; - Component name: The string "apk:" followed by the package name.
; - Security version: The long version code from the APK manifest
;   (https://developer.android.com/reference/android/content/pm/PackageInfo#getLongVersionCode()).
; - Code hash: This is the root hash of a Merkle tree computed over all bytes of the APK, as used
;   in the APK Signature Scheme v4 (https://source.android.com/docs/security/features/apksigning/v4)
;   with empty salt and using SHA-256 as the hash algorithm.
; - Authority hash: The SHA-512 hash of the DER representation of the X.509 certificate for the
;   public key used to sign the APK.
;
; For an APEX, they are as follows:
; - Component name: The string "apex:" followed by the APEX name as specified in the APEX Manifest
;   (see https://source.android.com/docs/core/ota/apex).
; - Security version: The version number from the APEX Manifest.
; - Code hash: The root hash of the apex_payload.img file within the APEX, taken from the first
;   hashtree descriptor in the VBMeta image
;   (see https://android.googlesource.com/platform/external/avb/+/master/README.md).
; - Authority hash: The SHA-512 hash of the public key used to sign the file system image in the
;   APEX (as stored in the apex_pubkey file). The format is as described for AvbRSAPublicKeyHeader
;   in https://cs.android.com/android/platform/superproject/main/+/main:external/avb/libavb/avb_crypto.h.
SubcomponentDescriptor = {
  1: tstr,                              ; Component name
  2: uint,                              ; Security version
  3: bstr,                              ; Code hash
  4: bstr,                              ; Authority hash
}