ecrust-ec

Elliptic-curve abstractions and point arithmetic for the ecrust ecosystem.

This crate builds on ecrust-fp and provides reusable curve and point APIs together with concrete models such as Weierstrass, Montgomery, Edwards, Hessian, and Jacobi forms.

What is in this crate?

• CurveOps: trait for curve-level operations
• PointOps: trait for generic group operations on points
• concrete curve and point types for several models
• scalar multiplication helpers and model-specific arithmetic

Adding it to your project

[dependencies]
ec = { package = "ecrust-ec", version = "0.1" }
fp = { package = "ecrust-fp", version = "0.1" }

Or, with the umbrella crate:

[dependencies]
ecrust = "0.1"

and then import from ecrust::ec and ecrust::fp.

Minimal example

use crypto_bigint::{Uint, const_prime_monty_params};
use ec::curve_weierstrass::WeierstrassCurve;
use ec::point_weierstrass::AffinePoint;
use fp::fp_element::FpElement;

const_prime_monty_params!(Fp19Mod, Uint<1>, "0000000000000013", 2);
type F19 = FpElement<Fp19Mod, 1>;

let curve = WeierstrassCurve::new_short(F19::from_u64(2), F19::from_u64(3));
let p = AffinePoint::new(F19::from_u64(1), F19::from_u64(5));

assert!(curve.contains(&p.x, &p.y));
let q = p.double(&curve);
let _r = p.add(&q, &curve);

Status

This crate is suitable for experimentation, education, and API exploration. It is not yet a hardened production implementation. In particular, some backends still contain exceptional-case branching and should not be assumed to provide full side-channel resistance.

Related crates

• ecrust-fp: finite-field arithmetic
• ecrust-isogeny: isogeny scaffolding on top of this layer
• ecrust-protocol: higher-level protocols
• ecrust: umbrella crate re-exporting the full stack

Authors

• Gustavo Banegas
• Martin Azon
• Sam Frengley

License

Apache-2.0