leetonidas/linearize

Control Flow Linearization

linearize

This Plugin performs Control Flow Linearization

Building

For building the obfuscator you habe two options:

1. build into llvm
2. standalone pass plugin

This obfuscation has only been tested on linux. both ways of building the obfuscation may work on Mac as well. On Windows only building the pass into llvm has a chance to succeed as to my knowledge pass plugins are not supported on windows in general.

build into llvm

First checkout version 16.0.6 of llvm-project. Then apply linearize_in_tree.patch in llvm-project, run cmake, and lastly build using ninja.

git clone --depth 1 --branch llvmorg-16.0.6 https://github.com/llvm/llvm-project
cd llvm-project
patch -p1 < ../linearize_in_tree.patch
cd -
mkdir build
cd build
cmake -DLLVM_ENABLE_PROJECTS=clang -DLLVM_ENABLE_ASSERTIONS=ON -G Ninja ../llvm-project/llvm
ninja
ninja install

build as pass plugin

Make sure you have llvm version 16.0.6 installed (minor version missmatches often times don't matter). If multiple llvm version are installed find the path to the cmake directory of llvm 16.0.6. Replace the path of the LLVM_DIR option with the pass to your installation

mkdir build
cd build
cmake -DLLVM_DIR=/usr/lib/cmake/llvm/ -G Ninja ..
ninja
ninja install

Usage

Usage depends on the build type

build into llvm

Just invoke clang with the -flinearize-cfg option on O1 or higher. In opt the pass is named --linearize.

Path application should be immediatly visible as the pass is very noise currently

pass plugin

Just invoke clang with the -fpass-plugin=Linearize.so option on O1 or higher. If plugin is not found you may need to use the full path to the plugin or make sure the directory containing the plugin is part of the library search path LD_LIBRARY_PATH