An implementation of Trevor Perrin's Noise Protocol that is designed to be Hard To Fuck Up™.
What's it look like?
examples/simple.rs for a more complete TCP client/server example.
let mut noise = snow::Builder::new("Noise_NN_25519_ChaChaPoly_BLAKE2s".parse()?) .build_initiator()?; let mut buf = [0u8; 65535]; // write first handshake message noise.write_message(&, &mut buf)?; // receive response message let incoming = receive_message_from_the_mysterious_ether(); noise.read_message(&incoming, &mut buf)?; // complete handshake, and transition the state machine into transport mode let mut noise = noise.into_transport_mode()?;
See the full documentation at https://docs.rs/snow.
Snow is currently tracking against Noise spec revision 34.
However, a not all features have been implemented yet (pull requests welcome):
Cryptographic providers are swappable through
Builder::with_resolver(), but by default
it chooses select, artisanal pure-Rust implementations (see
Cargo.toml for a quick
ring is a crypto library based off of BoringSSL and is significantly faster than most of the pure-Rust implementations.
If you enable the
ring-resolver feature, Snow will include a
as well as a
RingAcceleratedResolver available to be used with
If you enable the
ring-accelerated feature, Snow will default to choosing
crypto implementations when available.
libsodium is a fork of NaCl focused on improved usability and regular maintenance.
libsodium blacklists a set of low-order points that it deems unsafe because they would output an all-zeroes result.
Noise does not validate Curve25519 points, so if another Noise implementation provides an all-zero (or another low-order) public key for some reason (be it testing, or a real life foot-shot), if you use the libsodium backend of snow, it will error in a way that's not fully compatible with the specification.
Resolver primitives supported