Loading multiple/all entries of a ".a" file? (Lumina signature generation)

IDA General
1

For generating Lumina signatures of a Mono runtime library which is often statically compiled into Xamarin/MAUI apps I extracted an .a file which contains all relevant functions.

The main problem is that when I open that .a file in IDA 9.1 it forces me to select one of ~200 compiled objects. So I would have to open that .a file more than 200 times each time selecting a different contained compiled object. This makes Lumina signature generation a pretty nasty job.

Is there some way to load all compiled object files of an .a file into one IDA database or alternatively automate the Lumina signature generation?

2

Currently you have these options to push Lumina metadata automatically:

  • Create a script similar to this:
class MyUiHook(idaapi.UI_Hooks):
    def __init__(self):
        idaapi.UI_Hooks.__init__(self)

    def ready_to_run(self):
        idaapi.process_ui_action("LuminaPushAllMds", 0)
        idaapi.qexit(0)

idaapi.auto_wait()
uihook = MyUiHook()
uihook.hook()
  • launch IDA in batch mode with: idat -A -Spush2lum.py input_file

Alternatively, the decompiler can push functions to Lumina:
idat -A -Ohexrays:-lumina:output.c:ALL input_file_or_idb
see Batch operation | Hex-Rays Docs for more info.

To process each object, you can either extract them beforehand using ar (lib on Windows), or use the the nested -T switch, e.g.
ida -TAR:/path/to/file.o library.a

More info: Command line switches | Hex-Rays Docs and Igor’s tip of the week #07: IDA command-line options cheatsheet

Yet another option: link the archive into an executable or DLL while forcing inclusion of all objects, then open it in IDA. With MS’ linker , it would looks similar to:
link.exe /DLL /OUT:mylib.dll /NOENTRY /FORCE /OPT:NOICF /OPT:NOREF /WHOLEARHIVE mylib.lib
The same is likely achievable with ld or lld, but I don’t have the specifics.