dll-proxying.py

import os.path
import pefile

print('#pragma once')

target_dll = r'target.dll'
pe = pefile.PE(target_dll)
for export in pe.DIRECTORY_ENTRY_EXPORT.symbols:
    if export.name:
        name = export.name.decode()
        ordinal = export.ordinal
        basename = os.path.splitext(os.path.basename(target_dll))[0].replace('.', '_')
        print(f'#pragma comment(linker, "/export:{name}={basename}0.{name},@{ordinal}")')

print('''
VOID StartRoutine() {

}

BOOL APIENTRY DllMain(HMODULE hModule, DWORD fdwReason, LPVOID lpReserved)
{
    switch (fdwReason)
    {
    case DLL_PROCESS_ATTACH:
		if (!::OpenMutexA(SYNCHRONIZE, TRUE, ".text$mm"))
		{
			::CreateMutexA(NULL, TRUE, ".text$mm");
			::CreateThread(nullptr, 0, (LPTHREAD_START_ROUTINE)StartRoutine, nullptr, 0, nullptr);
		}
    case DLL_THREAD_ATTACH:
    case DLL_THREAD_DETACH:
    case DLL_PROCESS_DETACH:
        break;
    }
    return TRUE;
}
''')