Crate ed448_goldilocks_plus

Source
Expand description

This crate provides a pure Rust implementation of Curve448, Edwards, Decaf, and Ristretto. It is intended to be portable, fast, and safe.

§Usage

use ed448_goldilocks_plus::{EdwardsPoint, CompressedEdwardsY, Scalar, elliptic_curve::hash2curve::ExpandMsgXof, sha3::Shake256};
use rand_core::OsRng;

let secret_key = Scalar::TWO;
let public_key = EdwardsPoint::GENERATOR * &secret_key;

assert_eq!(public_key, EdwardsPoint::GENERATOR + EdwardsPoint::GENERATOR);

let secret_key = Scalar::random(&mut OsRng);
let public_key = EdwardsPoint::GENERATOR * &secret_key;
let compressed_public_key = public_key.compress();

assert_eq!(compressed_public_key.to_bytes().len(), 57);

let hashed_scalar = Scalar::hash::<ExpandMsgXof<Shake256>>(b"test", b"edwards448_XOF:SHAKE256_ELL2_RO_");
let input = hex_literal::hex!("c8c6c8f584e0c25efdb6af5ad234583c56dedd7c33e0c893468e96740fa0cf7f1a560667da40b7bde340a39252e89262fcf707d1180fd43400");
let expected_scalar = Scalar::from_canonical_bytes(&input.into()).unwrap();
assert_eq!(hashed_scalar, expected_scalar);

let hashed_point = EdwardsPoint::hash::<ExpandMsgXof<Shake256>>(b"test", b"edwards448_XOF:SHAKE256_ELL2_RO_");
let expected = hex_literal::hex!("d15c4427b5c5611a53593c2be611fd3635b90272d331c7e6721ad3735e95dd8b9821f8e4e27501ce01aa3c913114052dce2e91e8ca050f4980");
let expected_point = CompressedEdwardsY(expected).decompress().unwrap();
assert_eq!(hashed_point, expected_point);

let hashed_point = EdwardsPoint::hash_with_defaults(b"test");
assert_eq!(hashed_point, expected_point);

EdwardsPoint implements the elliptic_curve::Group and elliptic_curve::group::GroupEncoding and Scalar implements elliptic_curve::Field and elliptic_curve::PrimeField traits.

Re-exports§

Structs§

  • AffinePoint
    Affine point on untwisted curve
  • CompressedDecaf
    A compressed decaf point
  • CompressedEdwardsY
    Represents a point on the Compressed Twisted Edwards Curve in little endian format where the most significant bit is the sign bit and the remaining 448 bits represent the y-coordinate
  • CompressedRistretto
  • Decaf448
    Decaf448 curve.
  • DecafAffinePoint
    Affine point on the twisted curve
  • DecafPoint
  • Ed448
    Edwards448 curve.
  • EdwardsPoint
    Represent points on the (untwisted) edwards curve using Extended Homogenous Projective Co-ordinates (x, y) -> (X/Z, Y/Z, Z, T) a = 1, d = -39081 XXX: Make this more descriptive Should this be renamed to EdwardsPoint so that we are consistent with Dalek crypto? Necessary as ExtendedPoint is not regular lingo?
  • MontgomeryPoint
  • ProjectiveMontgomeryPoint
  • RistrettoPoint
  • Scalar
    This is the scalar field size = 4q = 2^446 - 0x8335dc163bb124b65129c96fde933d8d723a70aadc873d6d54a7bb0d We can therefore use 14 saturated 32-bit limbs

Constants§

Type Aliases§