Crate ed25519_compact

A compact Ed25519 implementation for Rust.

• Formally-verified Curve25519 field arithmetic
• no_std-friendly
• WebAssembly-friendly
• Compute@Edge-friendly
• Lightweight
• Zero dependencies if randomness is provided by the application
• Only one portable dependency (getrandom) if not
• Safe and simple Rust interface.

Example usage:

use ed25519_compact::*;

// A message to sign and verify.
let message = b"test";

// Generates a new key pair using a random seed.
// A given seed will always produce the same key pair.
let key_pair = KeyPair::from_seed(Seed::generate());

// Computes a signature for this message using the secret part of the key pair.
let signature = key_pair.sk.sign(message, Some(Noise::generate()));

// Verifies the signature using the public part of the key pair.
key_pair
    .pk
    .verify(message, &signature)
    .expect("Signature didn't verify");

// Verification of a different message using the same signature and public key fails.
key_pair
    .pk
    .verify(b"A different message", &signature)
    .expect_err("Signature shouldn't verify");

// All these structures can be viewed as raw bytes simply by dereferencing them:
let signature_as_bytes: &[u8] = signature.as_ref();
println!("Signature as bytes: {:?}", signature_as_bytes);

Cargo features:

• self-verify: after having computed a new signature, verify that is it valid. This is slower, but improves resilience against fault attacks. It is enabled by default on WebAssembly targets.
• std: disables no_std compatibility in order to make errors implement the standard Error trait.
• random (enabled by default): adds Default and generate implementations to the Seed and Noise objects, in order to securely create random keys and noise.

Structs

KeyPair	A key pair.
Noise	Noise, for non-deterministic signatures.
PublicKey	A public key.
SecretKey	A secret key.
Seed	A seed, which a key pair can be derived from.
Signature	An Ed25519 signature.

Enums

Error