How to integrate MSDM-table in UEFI-bios?

Discussion in 'BIOS Mods' started by Lutschpuppe, Jan 21, 2024.

  1. Lutschpuppe

    Lutschpuppe MDL Member

    Dec 23, 2014
    211
    57
    10
  2. Lutschpuppe

    Lutschpuppe MDL Member

    Dec 23, 2014
    211
    57
    10
    #2 Lutschpuppe, Jan 22, 2024
    Last edited: Jan 22, 2024
    (OP)
    Success! :cool:

    I compared 2 different OA3-PE-images in IDA and found some similarities, but wasn't able to find the location for key-insertion or structure. Fortunately, i have the matching bios-dump containing the correct structure, so it might work to copy it to the right offset.

    This is what i found in IDA Pro:
    ida-pro.JPG

    Corresponding RW-report after modding my own machine, i added a generic key for MS Windows 10 Pro:
    rw-msdm.JPG

    The key-string has to be added inside padding-area (AMI-bios), address found in IDA:
    uefi-tool-padding.JPG
    Take care to find the correct offset ; my first attempt was also succesful, but the address was not at the beginning of pad-area, because i worked with rom with empty NVRAM, so the free space was added on-top to the whole padding-area and i had to calculate the offset inside the pad-area.

    I don't know if this mod is permanent and will survive updates, but i guess it will.
    I'm sure most AMI-bios containing the same or similar OA3-module could be modded this way.