Crate k256

K-256 ([secp256k1]) elliptic curve.

⚠️ Security Warning

The elliptic curve arithmetic contained in this crate has never been independently audited!

This crate has been designed with the goal of ensuring that secret-dependent operations are performed in constant time (using the subtle crate and constant-time formulas). However, it has not been thoroughly assessed to ensure that generated assembly is constant time on common CPU architectures.

USE AT YOUR OWN RISK!

About K-256 (secp256k1)

K-256 is a Koblitz curve typically referred to as "[secp256k1]". The "K-256" name follows NIST notation where P = prime fields, B = binary fields, and K = Koblitz curves (defined over F₂).

The curve is specified as secp256k1 by Certicom's SECG in "SEC 2: Recommended Elliptic Curve Domain Parameters":

https://www.secg.org/sec2-v2.pdf

It's primarily notable for usage in Bitcoin and other cryptocurrencies.

Minimum Supported Rust Version

Rust 1.41 or higher.

Minimum supported Rust version can be changed in the future, but it will be done with a minor version bump.

Re-exports

pub use elliptic_curve;

Modules

ecdh	feature="ecdh" Elliptic Curve Diffie-Hellman (Ephemeral) Support.
ecdsa	feature="ecdsa-core" Elliptic Curve Digital Signature Algorithm (ECDSA).
test_vectors	feature="test-vectors" secp256k1 test vectors

Structs

AffinePoint	feature="arithmetic" A point on the secp256k1 curve in affine coordinates.
ProjectivePoint	feature="arithmetic" A point on the secp256k1 curve in projective coordinates.
Scalar	feature="arithmetic" An element in the finite field modulo curve order.
Secp256k1	K-256 (secp256k1) elliptic curve.

Type Definitions

CompressedPoint	K-256 Compressed Curve Point.
ElementBytes	K-256 Serialized Field Element.
NonZeroScalar	Non-zero scalar value.
PublicKey	K-256 (secp256k1) Public Key.
SecretKey	K-256 (secp256k1) Secret Key.
UncompressedPoint	K-256 Uncompressed Curve Point.