# libpermute

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[![Documentation](https://docs.rs/libpermute/badge.svg)](https://docs.rs/libpermute)

libpermute is a `no_std` compatible library that provides a function
to permute the items of a slice.

libpermute offers a few main features:

1. Stability. The permutation algorithm won't be changed without a
major version bump.

2. Re-implementability. It should be relatively straightforward to re-implement the algorithm
this library uses in another library or in another language.

3. Strength. Given an unpredictable permute_key, the permutation should also
be unpredictable - assuming that no one breaks the [Sha-256](https://en.wikipedia.org/wiki/SHA-2)
or [ChaChar20](https://en.wikipedia.org/wiki/Salsa20) algorithms.

# Example

```rust
use libpermute::permute;

fn main() {
    const KEY: &'static [u8] = &[0, 1, 2, 3, 4, 5, 6, 7];
    const INPUT: &str = "Hello World!";

    let mut buff = [0u8; INPUT.len()];
    buff.copy_from_slice(INPUT.as_bytes());

    permute(KEY, &mut buff);

    println!("RESULT: '{}'", std::str::from_utf8(&buff).unwrap());
}
```

## No_std

No_std mode may be activated by disabling the "std" feature.

## License

This project is licensed under either of

* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
  <https://www.apache.org/licenses/LICENSE-2.0>)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or
  <https://opensource.org/licenses/MIT>)

at your option.