History

tersec 90708a8287 Prefer converting int` to uint64 and switch foo.len.uint64 to .len64 (#1375 ) * avoid converting from uint64 to int, and where most feasible, int type conversion at all * .len.uint64 -> .len64 * fix 32-bit compilation * try keeping state_sim loop variable/bounds as int for 32-bit Azure * len64 -> lenu64		2020-07-26 20:55:48 +02:00
..
README.md	Allow defects and assertions to propagate in fuzzing harnesses.	2020-01-08 13:46:14 +02:00
libnfuzz.h	[WIP] Fake bls at runtime (#735 )	2020-03-05 13:52:10 +01:00
libnfuzz.nim	Prefer converting int` to uint64 and switch foo.len.uint64 to .len64 (#1375 )	2020-07-26 20:55:48 +02:00

README.md

Introduction

libnfuzz is a wrapper library that exports to C, a set of fuzzing test cases written in Nim and making use of nim-beacon-chain.

Building

To build the wrapper library (for more details follow first the instructions from nim-beacon-chain):

git clone https://github.com/status-im/nim-beacon-chain.git
cd nim-beacon-chain
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.