byte-mutator

byte-mutator is a crate for defining a set of rules by which to mutate byte arrays. It's intented to be used as part of a fuzzing workflow to configure how you want your input mutated. For example, you might want to do one pass where you don't mess with the header of your message, and you only mutate the body -- or you could mutate them differently.

Examples

BitFlipper

This example is configured to flip every bit in the bytes one at a time. ```rust let mut bytes = ByteMutator::new(b"foo").with_stages(vec![Stage { count: 0, iterations: Iterations::Bits, mutations: vec![Mutation { range: None, mutation: MutationType::BitFlipper { width: 1 }, }], }]);

// Bytes in their original state assert_eq!(bytes.read(), b"foo");

// Advance the mutation bytes.next();

// We've flipped the first bit (little endian) // 0b1100110 -> 0b1100111, 103 -> 102, f -> g assert_eq!(bytes.read(), b"goo"); ```

Load from config

This is an example of a mutator configured to flip bits forever. ```toml [[stages]] # Iteration count at which to start the loop (useful for starting over from a future state) count = 0 # Optional range to limit the number of times that this stage runs iterations = "Unlimited"

# A list of mutations to perform on this stage
[[stages.mutations]]
    # Must be a variant of the MutatorTypes enum
    mutation = {"BitFlipper" = {width = 1 }}

```

```rust let mut bytes = ByteMutator::newfromconfig(b"foo", FuzzConfig::from_file("config.toml"));

for _ in 0..20 { // this advances the state by one step bytes.next(); // each time this will be one bit different from the original dbg!(bytes.read()); } ```

Release History

0.1.0
- Initial release

Contributing

Always happy to see PRs or Issues.