Crate snow

The snow crate is a straightforward, Hard To Fuck Up™ Noise Protocol implementation.

Read the Noise Protocol Framework Spec for more information.

The typical usage flow is to use Builder to construct a HandshakeState, where you will complete the handshake phase and convert into either a TransportState or StatelessTransportState.

Examples

See examples/simple.rs for a more complete TCP client/server example with static keys.

static PATTERN: &'static str = "Noise_NN_25519_ChaChaPoly_BLAKE2s";

let mut initiator = snow::Builder::new(PATTERN.parse()?)
    .build_initiator()?;
let mut responder = snow::Builder::new(PATTERN.parse()?)
    .build_responder()?;

let (mut read_buf, mut first_msg, mut second_msg) =
    ([0u8; 1024], [0u8; 1024], [0u8; 1024]);

// -> e
let len = initiator.write_message(&[], &mut first_msg)?;

// responder processes the first message...
responder.read_message(&first_msg[..len], &mut read_buf)?;

// <- e, ee
let len = responder.write_message(&[], &mut second_msg)?;

// initiator processes the response...
initiator.read_message(&second_msg[..len], &mut read_buf)?;

// NN handshake complete, transition into transport mode.
let initiator = initiator.into_transport_mode();
let responder = responder.into_transport_mode();

Re-exports

• pub use crate::error::Error;

Modules

• error
  All error types used by Snow operations.
• params
  All structures related to Noise parameter definitions (cryptographic primitive choices, protocol patterns/names)
• resolvers
  The wrappers around the default collection of cryptography and entropy providers.
• types
  The traits for cryptographic implementations that can be used by Noise.

Structs

• Builder
  Generates a HandshakeState and also validates that all the prerequisites for the given parameters are satisfied.
• HandshakeState
  A state machine encompassing the handshake phase of a Noise session.
• Keypair
  A keypair object returned by Builder::generate_keypair()
• StatelessTransportState
  A state machine encompassing the transport phase of a Noise session, using the two CipherStates (for sending and receiving) that were spawned from the SymmetricState’s Split() method, called after a handshake has been finished.
• TransportState
  A state machine encompassing the transport phase of a Noise session, using the two CipherStates (for sending and receiving) that were spawned from the SymmetricState’s Split() method, called after a handshake has been finished.