Vendor Authorized Boot Image Manifest (Type 0x1C) Rules

VAB Image Manifest (Type 0x1C) entry in the FIT is required only for platforms which support Vendor Authorized Boot. It contains an Image Manifest Header and an Image Manifest. The VAB Image Manifest (Type 0x1C) is signed by a key in the VAB Key Manifest (Type 0x1B). The Image Manifest Header defines the number of Image Manifests. The Image Manifest contains hashes of firmware to be authorized. There can only be zero or one Type 0x1C record present in the FIT:

1. The Version field should be set to 0x0100.
2. The C_​V bit in this entry should be clear
3. The Checksum field is set to 0.
4. The entry must be 64 byte aligned.
5. Address + size must be under (4GB – 1) and above (4GB – 16MB).