src/org/gnunet/voting/TallyKeyShare.java


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package org.gnunet.voting;

import java.math.BigInteger;

/**
 * ...
 *
 * @author Florian Dold
 */
public class TallyKeyShare {
    final public BigInteger w;

    final public BigInteger sigma;

    final public BigInteger c1;
    final public BigInteger a, b, c, r;

    final VotingParameters parameters;

    public TallyKeyShare(BigInteger c1, BigInteger share, VotingParameters parameters) {
        this.parameters = parameters;
        this.c1 = c1;

        sigma = parameters.g.modPow(share, parameters.p);

        w = c1.modPow(share, parameters.p);

        BigInteger p = parameters.p;
        BigInteger g = parameters.g;

        // prover
        BigInteger beta = parameters.generateZq();
        a = g.modPow(beta, p);
        b = c1.modPow(beta, p);
        // verifier
        c = CryptoUtil.hash(a, b);
        // prover
        r = beta.add(share.multiply(c));
    }
}