Example #1
0
        public static bool VerifySignature(BigInteger[] publicKey, byte[] hash, BigInteger r, BigInteger s)
        {
            if (r >= Secp256k1.q || r.IsZero || s >= Secp256k1.q || s.IsZero)
            {
                return(false);
            }

            var  z  = Bytes32.ConvetToBigInteger(hash);;
            var  w  = s.ModInverse(Secp256k1.q);
            var  u1 = (z * w) % Secp256k1.q;
            var  u2 = (r * w) % Secp256k1.q;
            bool isZero;
            var  pt = Calculate.pointPlus(Calculate.getPublicByPrivate(u1), Calculate.getMulValue(u2, publicKey), out isZero);// (publicKey.Multiply(u2));

            if (pt == null)
            {
                return(false);
            }
            else
            {
                var pmod = pt[0] % Secp256k1.q;

                return(pmod == r);
            }
        }
Example #2
0
        public static string verify_message(string signature, string message, int addrtype)
        {
            byte[] sig;
            //try
            {
                sig = Convert.FromBase64String(signature);
            }
            //catch (err)
            //{
            //    return false;
            //}

            if (sig.Length != 65)
            {
                return("Error e");
            }

            // extract r,s from signature
            var r = Bytes32.ConvetToBigInteger(sig.Skip(1).Take(32).ToArray());
            var s = Bytes32.ConvetToBigInteger(sig.Skip(33).Take(32).ToArray());
            // var s = BigInteger.fromByteArrayUnsigned(sig.slice(33, 33 + 32));

            // get recid
            //  var compressed = false;
            var nV = Convert.ToInt32(sig[0]);

            if (nV < 27 || nV >= 35)
            {
                return("Error e");
            }
            if (nV >= 31)
            {
                //    compressed = true;
                nV -= 4;
            }
            var recid = new BigInteger(nV - 27);


            {
                //var z = Bytes32.ConvetToBigInteger(hash); ;
                //var w = s.ModInverse(Secp256k1.q);
                //var u1 = (z * w) % Secp256k1.q;
                //var u2 = (r * w) % Secp256k1.q;
                //bool isZero;
                //var pt = Calculate.pointPlus(Calculate.getPublicByPrivate(u1), Calculate.getMulValue(u2, publicKey), out isZero);// (publicKey.Multiply(u2));

                //if (pt == null)
                //{
                //    return false;
                //}
                //else
                //{
                //    var pmod = pt[0] % Secp256k1.q;

                //    return pmod == r;
                //}
            }
            //var ecparams = getSECCurveByName("secp256k1");
            //var curve = ecparams.getCurve();
            //var a = curve.getA().toBigInteger();
            //var b = curve.getB().toBigInteger();
            //var p = curve.getQ();
            //var G = ecparams.getG();
            //var order = ecparams.getN();

            //var x = r.add(order.multiply(recid.divide(BigInteger.valueOf(2))));
            var x = recid / 2 * Secp256k1.q + r;

            //Calculate.getMulValue(,recid / 2);
            // var alpha = x.multiply(x).multiply(x).add(a.multiply(x)).add(b).mod(p);
            var alpha = (x * x * x + Secp256k1.a * x + Secp256k1.b) % Secp256k1.p;
            //var beta = alpha.modPow(p.add(BigInteger.ONE).divide(BigInteger.valueOf(4)), p);
            var beta = BigInteger.ModPow(alpha, (Secp256k1.p + 1) / 4, Secp256k1.p);//Calculate.Pow((Secp256k1.p + 1) / 4, alpha);
            var y    = (beta - recid).IsEven ? beta : (Secp256k1.p - beta);
            //var y = beta.subtract(recid).isEven() ? beta : p.subtract(beta);

            //   var R = new ECPointFp(curve, curve.fromBigInteger(x), curve.fromBigInteger(y));
            // var e = BigInteger.fromByteArrayUnsigned(msg_digest(message));
            var e = Bytes32.ConvetToBigInteger(msg_digest(message));
            //    var minus_e = BigInteger.Negate(e)+ % Secp256k1.q;
            var minus_e = ((Secp256k1.q - e) % Secp256k1.q + Secp256k1.q) % Secp256k1.q;
            var inv_r   = ECCMain.Inverse.ex_gcd(r, Secp256k1.q);////BigInteger.mo r.modInverse(order);
            //var Q = (R.multiply(s).add(G.multiply(minus_e))).multiply(inv_r);
            bool isZero;
            var  Q__ = Calculate.pointPlus(Calculate.getMulValue(s, new BigInteger[] { x, y }),
                                           Calculate.getPublicByPrivate(minus_e), out isZero);

            if (isZero)
            {
                return("Error e");
            }
            else
            {
                var Q          = Calculate.getMulValue(inv_r, Q__);
                var public_key = PublicKeyF.GetAddressOfcompressed(Q);
                if (addrtype == 0)
                {
                    return(PublicKeyF.GetAddressOfUncompressed(Q));
                }
                else if (addrtype == 1)
                {
                    return(PublicKeyF.GetAddressOfcompressed(Q));
                }
                else
                {
                    return("Error e");
                }
            }
        }