curve25519-dalek-source/src/constants.rs

// -*- mode: rust; -*-
//
// This file is part of ed25519-dalek.
// Copyright (c) 2017-2019 isis lovecruft
// See LICENSE for licensing information.
//
// Authors:
// - isis agora lovecruft <isis@patternsinthevoid.net>

//! Common constants such as buffer sizes for keypairs and signatures.

/// The length of a ed25519 `Signature`, in bytes.
pub const SIGNATURE_LENGTH: usize = 64;

/// The length of a ed25519 `SecretKey`, in bytes.
pub const SECRET_KEY_LENGTH: usize = 32;

/// The length of an ed25519 `PublicKey`, in bytes.
pub const PUBLIC_KEY_LENGTH: usize = 32;

/// The length of an ed25519 `Keypair`, in bytes.
pub const KEYPAIR_LENGTH: usize = SECRET_KEY_LENGTH + PUBLIC_KEY_LENGTH;

/// The length of the "key" portion of an "expanded" ed25519 secret key, in bytes.
const EXPANDED_SECRET_KEY_KEY_LENGTH: usize = 32;

/// The length of the "nonce" portion of an "expanded" ed25519 secret key, in bytes.
const EXPANDED_SECRET_KEY_NONCE_LENGTH: usize = 32;

/// The length of an "expanded" ed25519 key, `ExpandedSecretKey`, in bytes.
pub const EXPANDED_SECRET_KEY_LENGTH: usize =
    EXPANDED_SECRET_KEY_KEY_LENGTH + EXPANDED_SECRET_KEY_NONCE_LENGTH;