Some IDA scripts to assist with reverse engineering EFI executables.
This package contains the following files:
efiutils.py- IDAPython module with some helper functions
efiguids.py- A collection of known GUIDs for EFI protocols
efiguids_ami.py- A collection of known GUIDs for protocols used in the AMI BIOS
behemoth.h- A giant header containing a collection of type and structure definitions for EFI
structs.idc- An IDC script containing some struct definitions (superseded by
te_image.bt- An 010 Editor template for TE binary images
te_loader.py- An IDA Pro loader script for TE binary images
This is my first attempt at IDA scripting, so please forgive me and let me know if I've reinvented wheels/done anything silly.
The main useful functions are described below. See code and docstrings for more information on other functions.
Finds the first entry point for the binary, tries to track the parameters that were passed to the entry point function and rename global variables in which the key EFI tables are stored. The following renaming operations are performed:
ImageHandleends up is renamed to
SystemTableends up is renamed to
SystemTable->BootServicesends up is renamed to
SystemTable->RuntimeServicesends up is renamed to
Call instructions will only be followed one level deep, as most executables copy the table references in the entry point or a function called from the entry point. Change
MAX_STACK_DEPTH if necessary.
Finds cross-references to tables renamed above, and updates their names to be struct offsets from the appropriate structs. If
rename_tables() failed you'll need to rename things manually as above for this to work properly.
mov rax, cs:qword_whatever call qword ptr [rax+150h]
mov rax, cs:gBootServices call [rax+EFI_BOOT_SERVICES.UninstallMultipleProtocolInterfaces]
Finds GUIDs in data segments and renames them. 470 protocol GUIDs were pulled out of the TianoCore source, and proprietary Apple (and other vendor) GUIDs will be added as they are encountered.
Convenience method that does all of the above.
Load up your EFI binary in IDA Pro
behemoth.hto define the necessary data structures
Add the structures from local types to your IDB
efiutils.pyto add it to python's path (or do this by some other method)
Have a look at the code/docstrings, but probably:
import efiutils; efiutils.go()
To use the
te_loader.py TE image loader, install it as you would any other loader. On OS X this is done by copying or symlinking it inside the loaders folder at