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afl.rs

Fuzzing Rust code with AFLplusplus

## What is it? [Fuzz testing][] is a software testing technique used to find security and stability issues by providing pseudo-random data as input to the software. [AFLplusplus][] is a popular, effective, and modern fuzz testing tool based on [AFL][american-fuzzy-lop]. This library, afl.rs, allows one to run AFLplusplus on code written in [the Rust programming language][rust]. ## Documentation Documentation can be found in the [Rust Fuzz Book](https://rust-fuzz.github.io/book/afl.html). ## What does it look like? Screen recording of afl Screen recording of AFL running on Rust code. ## Hints Before starting to fuzz, you should reconfigure your system for optimal performance and better crash detection. This can be done with `cargo afl system-config`. But this subcommand requires root, so it uses sudo internally. Hence, you might need to enter your password. By default, the AFL++ [CMPLOG](https://github.com/AFLplusplus/AFLplusplus/blob/stable/instrumentation/README.cmplog.md) feature is activated, which helps to achieve good code coverage. However, it is not beneficial to activate CMPLOG on more than two instances. So if you run multiple AFL++ instances on your fuzzing target, you can disable CMPLOG by specifying the command line parameter '-c -'. This [document](https://github.com/AFLplusplus/AFLplusplus/blob/stable/docs/fuzzing_in_depth.md) will familiarize you with AFL++ features to help in running a successful fuzzing campaign. By default, the `fuzzing` config is set when `cargo-afl` is used to build. If you want to prevent this, just set the environment variable `AFL_NO_CFG_FUZZING` to `1` when building. [conditional compilation]: https://doc.rust-lang.org/reference.html#conditional-compilation [Cargo feature]: http://doc.crates.io/manifest.html#the-[features]-section [example-defer]: https://github.com/frewsxcv/afl.rs/blob/master/examples/deferred-init.rs [LLVM pass]: https://github.com/frewsxcv/afl.rs/blob/master/plugin/src/afl-llvm-pass.o.cc [example]: https://github.com/frewsxcv/afl.rs/blob/master/afl/examples/hello.rs [Cargo]: http://doc.crates.io/ [unresolved issue]: https://github.com/frewsxcv/afl.rs/issues/11 [fuzz testing]: https://en.wikipedia.org/wiki/Fuzz_testing [rustup]: https://rustup.rs/ [american-fuzzy-lop]: http://lcamtuf.coredump.cx/afl/ [AFLplusplus]: https://aflplus.plus/ [rust]: https://www.rust-lang.org