@stellot/crypto/lib/esm/blindSignature/VoterSession.js

Crypto libraries for front and backend

import { ed25519 } from './index';
import { randomScalar } from './utils';
export default class VoterSession {
    constructor(P, R, a, b) {
        this.a = a || randomScalar();
        this.b = b || randomScalar();
        this.P = ed25519.decodePoint(P);
        this.R = ed25519.decodePoint(R)
            .add(ed25519.curve.g.mul(this.a).add(this.P.mul(this.b)));
    }
    challenge(message) {
        return ed25519
            .hashInt(ed25519.encodePoint(this.R), ed25519.encodePoint(this.P), message)
            .add(this.b)
            .umod(ed25519.curve.n);
    }
    proof() {
        return { a: this.a, b: this.b };
    }
    signature(s) {
        const S = s.add(this.a).umod(ed25519.curve.n);
        const signature = ed25519.encodePoint(this.R).concat(ed25519.encodeInt(S));
        return signature;
    }
    toJSON() {
        return {
            a: this.a,
            b: this.b,
            P: ed25519.encodePoint(this.P),
            R: ed25519.encodePoint(this.R),
        };
    }
}