roaminro / ecvrf

Elliptic Curve Verifiable Random Function (VRF) using the secp256k1 curve

Verifiable Random Function (VRF)

This library has an implementation of an ECVRF based on the IETF draft 05 using the secp256k1 curve, SHA256 as hash function and try-and-increment as hash to curve method (cipher suite SECP256K1_SHA256_TAI). The cipher suite code used is 0xFE for compatibility with other implementations.

Node

# with npm
npm install @roamin/ecvrf

# with yarn
yarn add @roamin/ecvrf

Usage

const { prove, proofToHash, verify } = require('@roamin/ecvrf');
const elliptic = require('elliptic');

const EC = new elliptic.ec('secp256k1');

const SECRET = EC.keyPair({ priv: 'c9afa9d845ba75166b5c215767b1d6934e50c3db36e89b127b8a622b120f6721', privEnc: 'hex' });

const msg = Buffer.from('sample').toString('hex');

// VRF proof and hash output
const proof = prove(SECRET.getPrivate('hex'), msg);
const hash = proofToHash(proof);

// VRF proof verification (returns VRF hash output)
const beta = verify(SECRET.getPublic('hex'), proof, msg);