This repository contains scripts for building a Clang toolchain that can target
LFI. The build process here does not build or include Clang, and expects you to
already have a version of Clang installed on your system. These scripts use
your version of Clang to build the following runtime libraries for use with
LFI: compiler-rt, musl-libc, libc++ (and dependencies). This means that
the resulting toolchain can compile C and C++ programs.
The runtime libraries are currently built from LLVM 16.0.6, so your local Clang
should match this version (ideally), but you can change this version number in
install-toolchain.sh.
To run the build, you must have lld, ninja, and cmake installed.
Additionally, in order to build libc++, you may need to symlink
/usr/include/asm-generic to /usr/include/asm.
sudo ln -s /usr/include/asm-generic /usr/include/asm
First, you must install lfi-compile and lfi-leg-arm64 from the LFI project.
Next, run the scripts:
$ ./install-toolchain.sh $PWD/lfi-clang
Once the build is complete, you can use your new toolchain to build programs for LFI.
$ ./lfi-clang/bin/lfi-clang -O2 test.c
$ lfi-run ./a.out
Hello world: 0x1e00050000
$ ./lfi-clang/bin/lfi-clang++ -O2 test.cc
$ lfi-run ./a.out
done!