rand_chacha

A cryptographically secure random number generator that uses the ChaCha algorithm.

This implementation of ChaCha RNGs is built over ppv-lite86 by Kaz Wesley, and was formerly the implementation behind rand::rngs::StdRng.

ChaCha is a stream cipher designed by Daniel J. Bernstein¹, that we use as an RNG. It is an improved variant of the Salsa20 cipher family, which was selected as one of the "stream ciphers suitable for widespread adoption" by eSTREAM².

The RNGs provided by this crate are implemented via the fast stream ciphers of the c2-chacha crate.

Links:

• API documentation (docs.rs)
• Changelog

Crate Features

rand_chacha is no_std compatible when disabling default features; the std feature can be explicitly required to re-enable std support. Using std allows detection of CPU features and thus better optimisation.

License

rand_chacha is distributed under the terms of both the MIT license and the Apache License (Version 2.0).

See LICENSE-APACHE and LICENSE-MIT, and COPYRIGHT for details.

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1. D. J. Bernstein, ChaCha, a variant of Salsa20 ↩︎

2. eSTREAM: the ECRYPT Stream Cipher Project ↩︎