HoldOn

Description

HoldOn is a Windows x64 software designed to intercept and edit network packets before their sending/delivery from/to a process.

You must have installed the Visual Studio 2019 packages.
You must have installed the MinGW msys packages.
You must have installed the Java SE Development Kit 8.
You must have configured your environment variables the following way :
- JAVA_HOME: Must contain *\Java\jdk8XXXX-XXX\
- Path: Must contain *\MinGW\msys\1.0\bin\ and %JAVA_HOME%\bin\

prepare_env.bat :
- You must set WIN_KITS_VERSION to the name of the directory located under *\Windows Kits\XX\Include\ and that contains a directory named ucrt.
Makefile :
- You must set MSVC_VERSION to the name of the directory located under *\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\
- You must set WIN_KITS_VERSION to the name of the directory located under *\Windows Kits\XX\Include\ and that contains a directory named ucrt.

Open a terminal in HoldOn root directory.
Enter command prepare_env to setup your environment variables for the Makefile.
Enter command make clean to remove files from previous builds.
Enter command make or make HoldOn to run the Makefile that will compile all sources and produce the executable.

The first thing to do after HoldOn is started, is to attach to the 64-bit process of your choice.
If the process sends or receives network packets, you should see them in the console (left panel) and the graph (top right panel).
To start editing them, you need to press the pause button () and wait for the next packet to load.
Then, you can edit the packet by changing values in both the HEX and ASCII panels.
Finally, you need to resume the process by pressing the resume button () or wait for the next packet to load by pressing the single-step button ().