1.5 KiB
Introduction
libnfuzz is a wrapper library that exports to C, a set of fuzzing test cases
written in Nim and making use of nimbus-eth2.
Building
To build the wrapper library (for more details follow first the instructions from nimbus-eth2):
git clone https://github.com/status-im/nimbus-eth2.git
cd nimbus-eth2
make
# static library
make libnfuzz.a
# dynamic loaded library
make libnfuzz.so
Default, the library is build with the minimal config. To select a specific config you can instead run:
# build with mainnet config
make libnfuzz.a NIMFLAGS="-d:const_preset=mainnet"
For the library to be useful for fuzzing with libFuzzer (e.g. for integration with beacon-fuzz) we can pass additional Nim arguments, e.g.:
make libnfuzz.a NIMFLAGS="--cc:clang --passC:'-fsanitize=fuzzer-no-link' --passL='-fsanitize=fuzzer'"
To disable BLS verification on deserialization of SSZ objects add -d:ssz_testing to the NIMFLAGS.
Other useful options might include: --clang.path:<path>, --clang.exe:<exe>, --clang.linkerexe:<exe>, -d:const_preset=mainnet
It might also deem useful to lower the log level, e.g. by adding -d:chronicles_log_level=fatal.
Usage
There is a libnfuzz.h file provided for easy including in C or C++ projects.
It is most important that before any of the exported tests are called, the
NimMain() call is done first. Additionally, all following library calls need
to be done from the same thread as from where the original NimMain() call was
done.