cough

A library for building COFF object files.

Tutorial

Start with the ObjectModule class:

module = ObjectModule()

Now, let's create a '.text' section:

section = Section(b'.text', SectionFlags.MEM_EXECUTE)

Add a bit of code:

section.data = b'\x29\xC0\xC3'  # return 0
section.size_of_raw_data = len(section.data)

Good enough, let's add it to our module:

module.sections.append(section)

To make use of that bit of code, we are going to need an exported symbol:

main = SymbolRecord(b'main', section_number=1, storage_class=StorageClass.EXTERNAL)

Set the value to the offset in the section:

main.value = 0

And add it to our module:

module.symbols.append(main)

That's enough, let's write our module to a file:

with open('test.obj', 'wb') as obj_file:
    obj_file.write(module.get_buffer())