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DetoursNT

DetoursNT is a simple project with one goal - make Detours dependent only on NTDLL.DLL without any modifications of the original code.

Why?

  • Because this way you can hook native processes.
  • Because this way you can load your hooking library right after load of NTDLL.DLL
    • This can be achieved in many ways - for example using Windows Driver via so-called APC injection. You can look at my project injdrv to get an idea about how is this done.

How?

This repository has attached original git repository of Detours from Microsoft as a submodule. Therefore, the original code hasn't been touched in any way.

NTDLL-only dependency been achieved by creating a C header file DetoursNT.h which has been force-included (/FI switch of MSVC) into every compilation unit of Detours. This header mocks functions of KERNEL32.DLL to custom implementation defined in DetoursNT.cpp.

I'd like to thank authors of following projects:

  • ReactOS - used for implementation of KERNEL32.DLL functions
  • ProcessHacker - used for prototypes of NTDLL.DLL functions

Compilation

Because original Detours source code is attached as a git submodule, you must not forget to fetch it:

git clone --recurse-submodules https://github.com/wbenny/DetoursNT

After that, compile DetoursNT using Visual Studio 2017. Solution file is included. No other dependencies are required.

Usage

After you hit F7 in Visual Studio and have everything compiled, you can check that SampleHookDLL.dll indeed depends only on NTDLL.DLL:

Dependency Walker

This hooking DLL only hooks NtTestAlert function for demonstrative purposes. In this repository there is also Sample project. It's only purpose is to call LoadLibrary(TEXT("SampleHookDLL.dll")), NtTestAlert() and FreeLibrary() to show you that the hook is working.

Sample

Remarks

  • This implementation intentionally crashes on SEH exceptions which occur inside of Detours. This is because SEH handlers are usually located in CRT (which is ommited here).
  • Supported architectures are: x86, x64, ARM (32-bit) and ARM64.

License

This software is open-source under the MIT license. See the LICENSE.txt file in this repository.

Detours is licensed under MIT license (a copy of the license is included in separate git submodule)

If you find this project interesting, you can buy me a coffee

  BTC 3GwZMNGvLCZMi7mjL8K6iyj6qGbhkVMNMF
  LTC MQn5YC7bZd4KSsaj8snSg4TetmdKDkeCYk