Пример #1
0
        /// <summary>
        /// Evaluates the shared secrets of secret with polynom of degree t and numberOfPlayers players.
        /// </summary>
        public static ShareDetails DetailedShare(Zp secret,
            int numPlayers, int polynomDeg)
        {
            if (numPlayers <= polynomDeg)
                throw new ArgumentException("Polynomial degree cannot be bigger or equal to the number of  players");

            // Creating the Random Polynomial - f(x)
            var randomMatrix = ZpMatrix.GetRandomMatrix(1, polynomDeg + 1, secret.Prime);

            // The free variable in the Random Polynomial( f(x) ) is the seceret
            randomMatrix.SetMatrixCell(0, 0, secret);

            // Create vanderMonde matrix
            var vanderMonde = ZpMatrix.GetPrimitiveVandermondeMatrix(polynomDeg + 1, numPlayers, secret.Prime);

            // Compute f(i) for the i-th  player
            var sharesArr = randomMatrix.Times(vanderMonde).ZpVector;

            var details = new ShareDetails(randomMatrix.GetMatrixRow(0), sharesArr);
            return details;
        }
Пример #2
0
        /// <summary>
        /// Evaluates the shared secrets of secret with polynom of degree t and numberOfPlayers players.
        /// </summary>
        public static ShareDetails DetailedShare(Zp secret,
                                                 int numPlayers, int polynomDeg)
        {
            if (numPlayers <= polynomDeg)
            {
                throw new ArgumentException("Polynomial degree cannot be bigger or equal to the number of  players");
            }

            // Creating the Random Polynomial - f(x)
            var randomMatrix = ZpMatrix.GetRandomMatrix(1, polynomDeg + 1, secret.Prime);

            // The free variable in the Random Polynomial( f(x) ) is the seceret
            randomMatrix.SetMatrixCell(0, 0, secret);

            // Create vanderMonde matrix
            var vanderMonde = ZpMatrix.GetPrimitiveVandermondeMatrix(polynomDeg + 1, numPlayers, secret.Prime);

            // Compute f(i) for the i-th  player
            var sharesArr = randomMatrix.Times(vanderMonde).ZpVector;

            var details = new ShareDetails(randomMatrix.GetMatrixRow(0), sharesArr);

            return(details);
        }
Пример #3
0
        private IList<Zp> ConstructRxPolynomial(ShareDetails aSharesDetails,
			ShareDetails bSharesDetails, ShareDetails abSharesDetails, ShareDetails rSharesDetails)
        {
            var fax = aSharesDetails.RandomPolynomial;
            var fbx = bSharesDetails.RandomPolynomial;
            var hx = abSharesDetails.RandomPolynomial;
            var rx = rSharesDetails.RandomPolynomial;

            var RxPolynomial = new Zp[2 * PolynomialDeg + 1];
            /* Initialize RxPolynomial coefs with zeros  */
            for (int i = 0; i < 2 * PolynomialDeg + 1; i++)
                RxPolynomial[i] = new Zp(Prime, 0);

            /* First calculate fax*fbx - hx */
            for (int i = 0; i < fax.Count; i++)
            {
                Zp temp = fax[i];
                for (int j = 0; j < fax.Count; j++)
                    RxPolynomial[i + j].Add(temp.ConstMul(fbx[j]));

                RxPolynomial[i].Sub(hx[i]);
            }
            /* Calculate x*rx+fax*fbx - hx*/
            for (int i = 0; i < rx.Count; i++)
                RxPolynomial[i + 1].Add(rx[i]);

            return new List<Zp>(RxPolynomial);
        }