Inheritance: ECFieldElement
Example #1
0
        public Cypher GetCypher(string message)
        {
            BigInteger x = GeneralFunctions.H1hash(ID, prim);
            BigInteger y = x.Pow(3).Add(new BigInteger("7", 10)).Pow(2).ModInverse(prim);
            FpFieldElement x_Qid = new FpFieldElement(E.Q, x);
            FpFieldElement y_Qid = new FpFieldElement(E.Q, y);
            FpPoint Qid = new FpPoint(E, x_Qid, y_Qid);

            int r = 0;
            do
            {
                Random rnd = new Random();
                r = rnd.Next(1, int.MaxValue - 1);
            } while (r == 0);

            FpPoint rP = (FpPoint)P.Multiply(new BigInteger(r.ToString(), 10));

            BigInteger gid = GeneralFunctions.Pair(Qid, Ppub, k, prim);
            gid = gid.ModPow(new BigInteger(r.ToString(), 10), prim);

            char[] M = message.ToCharArray();
            char[] cArray = new char[M.Length];
            char[] hash = GeneralFunctions.H2hash(gid, prim).ToCharArray();
            for (int i = 0; i < message.Length; i++)
            {
                cArray[i] = (char)(M[i] ^ hash[i % hash.Length]);
            }

            string c = new String(cArray);

            return new Cypher { U = rP, V = c };
        }
Example #2
0
 public virtual bool Equals(FpFieldElement other)
 {
     if (q.Equals(other.q))
     {
         return(base.Equals(other));
     }
     return(false);
 }
Example #3
0
        /**
         * Decode a point on this curve from its ASN.1 encoding. The different
         * encodings are taken account of, including point compression for
         * <code>F<sub>p</sub><code> (X9.62 s 4.2.1 pg 17).
         * @return The decoded point.
         */
        public override ECPoint DecodePoint(
            byte[] encoded)
        {
            ECPoint p = null;

            switch (encoded[0])
            {
            // compressed
            case 0x02:
            case 0x03:
                int    ytilde = encoded[0] & 1;
                byte[] i      = new byte[encoded.Length - 1];

                Array.Copy(encoded, 1, i, 0, i.Length);

                ECFieldElement x     = new FpFieldElement(this.q, new BigInteger(1, i));
                ECFieldElement alpha = x.Multiply(x.Square()).Add(x.Multiply(a).Add(b));
                ECFieldElement beta  = alpha.Sqrt();

                //
                // if we can't find a sqrt we haven't got a point on the
                // curve - run!
                //
                if (beta == null)
                {
                    throw new ArithmeticException("Invalid point compression");
                }

                BigInteger betaValue = beta.ToBigInteger();
                int        bit0      = betaValue.TestBit(0) ? 1 : 0;

                if (bit0 != ytilde)
                {
                    // Use the other root
                    beta = new FpFieldElement(q, q.Subtract(betaValue));
                }

                p = new FpPoint(this, x, beta, true);
                break;

            case 0x04:
                byte[] xEnc = new byte[(encoded.Length - 1) / 2];
                byte[] yEnc = new byte[(encoded.Length - 1) / 2];

                Array.Copy(encoded, 1, xEnc, 0, xEnc.Length);
                Array.Copy(encoded, xEnc.Length + 1, yEnc, 0, yEnc.Length);

                p = new FpPoint(this,
                                new FpFieldElement(this.q, new BigInteger(1, xEnc)),
                                new FpFieldElement(this.q, new BigInteger(1, yEnc)));
                break;

            default:
                throw new FormatException("Invalid point encoding " + encoded[0]);
            }

            return(p);
        }
Example #4
0
        public override bool Equals(object obj)
        {
            if (obj == this)
            {
                return(true);
            }
            FpFieldElement fpFieldElement = obj as FpFieldElement;

            return(fpFieldElement != null && this.Equals(fpFieldElement));
        }
Example #5
0
 public FpCurve(BigInteger q, BigInteger a, BigInteger b, BigInteger order, BigInteger cofactor) : base(q)
 {
     this.m_q        = q;
     this.m_r        = FpFieldElement.CalculateResidue(q);
     this.m_infinity = new FpPoint(this, null, null);
     base.m_a        = this.FromBigInteger(a);
     base.m_b        = this.FromBigInteger(b);
     base.m_order    = order;
     base.m_cofactor = cofactor;
     base.m_coord    = 4;
 }
Example #6
0
			/**
			 * Creates the points on the curve with literature values.
			 */
			internal static void createPoints()
			{
				for (int i = 0; i < pointSource.Length / 2; i++)
				{
					FpFieldElement x = new FpFieldElement(q, new BigInteger(
						pointSource[2 * i].ToString()));
					FpFieldElement y = new FpFieldElement(q, new BigInteger(
						pointSource[2 * i + 1].ToString()));
					p[i] = new FpPoint(curve, x, y);
				}
			}
Example #7
0
        public FpCurve(BigInteger q, BigInteger a, BigInteger b, BigInteger order, BigInteger cofactor)
            : base(FiniteFields.GetPrimeField(q))
        {
            this.m_q        = q;
            this.m_r        = FpFieldElement.CalculateResidue(q);
            this.m_infinity = new FpPoint(this, null, null);

            this.m_a        = FromBigInteger(a);
            this.m_b        = FromBigInteger(b);
            this.m_order    = order;
            this.m_cofactor = cofactor;
            this.m_coord    = FP_DEFAULT_COORDS;
        }
Example #8
0
        public override bool Equals(object obj)
        {
            if (obj == this)
            {
                return(true);
            }
            FpFieldElement fpFieldElement = obj as FpFieldElement;

            if (fpFieldElement == null)
            {
                return(false);
            }
            return(Equals(fpFieldElement));
        }
Example #9
0
        public override bool Equals(object obj)
        {
            if (obj == this)
            {
                return(true);
            }
            FpFieldElement other = obj as FpFieldElement;

            if (other == null)
            {
                return(false);
            }
            return(this.Equals(other));
        }
Example #10
0
        /**
         * Decode a point on this curve from its ASN.1 encoding. The different
         * encodings are taken account of, including point compression for
         * <code>F<sub>p</sub></code> (X9.62 s 4.2.1 pg 17).
         * @return The decoded point.
         */
        public override ECPoint DecodePoint(
			byte[] encoded)
        {
            ECPoint p = null;

            switch (encoded[0])
            {
                // compressed
                case 0x02:
                case 0x03:
                    int ytilde = encoded[0] & 1;
                    byte[] i = new byte[encoded.Length - 1];

                    Array.Copy(encoded, 1, i, 0, i.Length);

                    ECFieldElement x = new FpFieldElement(this.q, new BigInteger(1, i));
                    ECFieldElement alpha = x.Multiply(x.Square()).Add(x.Multiply(a).Add(b));
                    ECFieldElement beta = alpha.Sqrt();

                    //
                    // if we can't find a sqrt we haven't got a point on the
                    // curve - run!
                    //
                    if (beta == null)
                        throw new ArithmeticException("Invalid point compression");

                    BigInteger betaValue = beta.ToBigInteger();
                    int bit0 = betaValue.TestBit(0) ? 1 : 0;

                    if (bit0 != ytilde)
                    {
                        // Use the other root
                        beta = new FpFieldElement(q, q.Subtract(betaValue));
                    }

                    p = new FpPoint(this, x, beta, true);
                    break;
                case 0x04:
                    byte[] xEnc = new byte[(encoded.Length - 1) / 2];
                    byte[] yEnc = new byte[(encoded.Length - 1) / 2];

                    Array.Copy(encoded, 1, xEnc, 0, xEnc.Length);
                    Array.Copy(encoded, xEnc.Length + 1, yEnc, 0, yEnc.Length);

                    p = new FpPoint(this,
                        new FpFieldElement(this.q, new BigInteger(1, xEnc)),
                        new FpFieldElement(this.q, new BigInteger(1, yEnc)));
                    break;
                default:
                    throw new FormatException("Invalid point encoding " + encoded[0]);
            }

            return p;
        }
 protected bool Equals(
     FpFieldElement other)
 {
     return(q.Equals(other.q) && base.Equals(other));
 }
        // D.1.4 91

        /**
         * return a sqrt root - the routine verifies that the calculation
         * returns the right value - if none exists it returns null.
         */
        public override ECFieldElement Sqrt()
        {
            if (!q.TestBit(0))
            {
                throw Platform.CreateNotImplementedException("even value of q");
            }

            // p mod 4 == 3
            if (q.TestBit(1))
            {
                // TODO Can this be optimised (inline the Square?)
                // z = g^(u+1) + p, p = 4u + 3
                ECFieldElement z = new FpFieldElement(q, x.ModPow(q.ShiftRight(2).Add(BigInteger.One), q));

                return(z.Square().Equals(this) ? z : null);
            }

            // p mod 4 == 1
            BigInteger qMinusOne = q.Subtract(BigInteger.One);

            BigInteger legendreExponent = qMinusOne.ShiftRight(1);

            if (!(x.ModPow(legendreExponent, q).Equals(BigInteger.One)))
            {
                return(null);
            }

            BigInteger u = qMinusOne.ShiftRight(2);
            BigInteger k = u.ShiftLeft(1).Add(BigInteger.One);

            BigInteger Q     = this.x;
            BigInteger fourQ = Q.ShiftLeft(2).Mod(q);

            BigInteger U, V;

            do
            {
                Random     rand = new Random();
                BigInteger P;
                do
                {
                    P = new BigInteger(q.BitLength, rand);
                }while (P.CompareTo(q) >= 0 ||
                        !(P.Multiply(P).Subtract(fourQ).ModPow(legendreExponent, q).Equals(qMinusOne)));

                BigInteger[] result = fastLucasSequence(q, P, Q, k);
                U = result[0];
                V = result[1];

                if (V.Multiply(V).Mod(q).Equals(fourQ))
                {
                    // Integer division by 2, mod q
                    if (V.TestBit(0))
                    {
                        V = V.Add(q);
                    }

                    V = V.ShiftRight(1);

                    Debug.Assert(V.Multiply(V).Mod(q).Equals(x));

                    return(new FpFieldElement(q, V));
                }
            }while (U.Equals(BigInteger.One) || U.Equals(qMinusOne));

            return(null);


//			BigInteger qMinusOne = q.Subtract(BigInteger.One);
//
//			BigInteger legendreExponent = qMinusOne.ShiftRight(1);
//			if (!(x.ModPow(legendreExponent, q).Equals(BigInteger.One)))
//				return null;
//
//			Random rand = new Random();
//			BigInteger fourX = x.ShiftLeft(2);
//
//			BigInteger r;
//			do
//			{
//				r = new BigInteger(q.BitLength, rand);
//			}
//			while (r.CompareTo(q) >= 0
//				|| !(r.Multiply(r).Subtract(fourX).ModPow(legendreExponent, q).Equals(qMinusOne)));
//
//			BigInteger n1 = qMinusOne.ShiftRight(2);
//			BigInteger n2 = n1.Add(BigInteger.One);
//
//			BigInteger wOne = WOne(r, x, q);
//			BigInteger wSum = W(n1, wOne, q).Add(W(n2, wOne, q)).Mod(q);
//			BigInteger twoR = r.ShiftLeft(1);
//
//			BigInteger root = twoR.ModPow(q.Subtract(BigInteger.Two), q)
//				.Multiply(x).Mod(q)
//				.Multiply(wSum).Mod(q);
//
//			return new FpFieldElement(q, root);
        }
Example #13
0
 public FpFieldElement(BigInteger q, BigInteger x) : this(q, FpFieldElement.CalculateResidue(q), x)
 {
 }
Example #14
0
 private FiniteFieldElement(FpFieldElement innerField)
 {
     _field = innerField;
 }
Example #15
0
 public virtual bool Equals(
     FpFieldElement other)
 {
     return q.Equals(other.q) && base.Equals(other);
 }
Example #16
0
		// D.1.4 91
		/**
		 * return a sqrt root - the routine verifies that the calculation
		 * returns the right value - if none exists it returns null.
		 */
		public override ECFieldElement Sqrt()
		{
			if (!q.TestBit(0))
				throw Platform.CreateNotImplementedException("even value of q");

			// p mod 4 == 3
			if (q.TestBit(1))
			{
				// TODO Can this be optimised (inline the Square?)
				// z = g^(u+1) + p, p = 4u + 3
				ECFieldElement z = new FpFieldElement(q, x.ModPow(q.ShiftRight(2).Add(BigInteger.One), q));

                return this.Equals(z.Square()) ? z : null;
			}

			// p mod 4 == 1
			BigInteger qMinusOne = q.Subtract(BigInteger.One);

			BigInteger legendreExponent = qMinusOne.ShiftRight(1);
			if (!(x.ModPow(legendreExponent, q).Equals(BigInteger.One)))
				return null;

			BigInteger u = qMinusOne.ShiftRight(2);
			BigInteger k = u.ShiftLeft(1).Add(BigInteger.One);

			BigInteger Q = this.x;
			BigInteger fourQ = Q.ShiftLeft(2).Mod(q);

			BigInteger U, V;
			do
			{
				Random rand = new Random();
				BigInteger P;
				do
				{
					P = new BigInteger(q.BitLength, rand);
				}
				while (P.CompareTo(q) >= 0
					|| !(P.Multiply(P).Subtract(fourQ).ModPow(legendreExponent, q).Equals(qMinusOne)));

				BigInteger[] result = fastLucasSequence(q, P, Q, k);
				U = result[0];
				V = result[1];

				if (V.Multiply(V).Mod(q).Equals(fourQ))
				{
					// Integer division by 2, mod q
					if (V.TestBit(0))
					{
						V = V.Add(q);
					}

					V = V.ShiftRight(1);

					Debug.Assert(V.Multiply(V).Mod(q).Equals(x));

					return new FpFieldElement(q, V);
				}
			}
			while (U.Equals(BigInteger.One) || U.Equals(qMinusOne));

			return null;


//			BigInteger qMinusOne = q.Subtract(BigInteger.One);
//
//			BigInteger legendreExponent = qMinusOne.ShiftRight(1);
//			if (!(x.ModPow(legendreExponent, q).Equals(BigInteger.One)))
//				return null;
//
//			Random rand = new Random();
//			BigInteger fourX = x.ShiftLeft(2);
//
//			BigInteger r;
//			do
//			{
//				r = new BigInteger(q.BitLength, rand);
//			}
//			while (r.CompareTo(q) >= 0
//				|| !(r.Multiply(r).Subtract(fourX).ModPow(legendreExponent, q).Equals(qMinusOne)));
//
//			BigInteger n1 = qMinusOne.ShiftRight(2);
//			BigInteger n2 = n1.Add(BigInteger.One);
//
//			BigInteger wOne = WOne(r, x, q);
//			BigInteger wSum = W(n1, wOne, q).Add(W(n2, wOne, q)).Mod(q);
//			BigInteger twoR = r.ShiftLeft(1);
//
//			BigInteger root = twoR.ModPow(q.Subtract(BigInteger.Two), q)
//				.Multiply(x).Mod(q)
//				.Multiply(wSum).Mod(q);
//
//			return new FpFieldElement(q, root);
		}
Example #17
0
            protected override X9ECParameters CreateParameters()
            {
                // p = 2^224 - 2^96 + 1
                BigInteger secp224r1P = new BigInteger(
                    "26959946667150639794667015087019630673557916260026308143510066298881");

                // a = -3, b = b4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4
                ECCurve secp224r1Curve = new FpCurve(secp224r1P,
                    new BigInteger("26959946667150639794667015087019630673557916260026308143510066298878"),
                    new BigInteger("b4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4", 16));

                // x = b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21
                ECFieldElement secp224r1x = new FpFieldElement(
                    secp224r1P,
                    new BigInteger("b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21", 16));

                // y = bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34
                ECFieldElement secp224r1y = new FpFieldElement(
                    secp224r1P,
                    new BigInteger("bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34", 16));

                ECPoint secp224r1BasePoint = new FpPoint(
                    secp224r1Curve, secp224r1x, secp224r1y, false);

                BigInteger secp224r1n = new BigInteger("26959946667150639794667015087019625940457807714424391721682722368061");

                BigInteger secp224r1h = new BigInteger("1");

                //static readonly byte[] secp224r1Seed = (Hex.decode("bd71344799d5c7fcdc45b59fa3b9ab8f6a948bc5"));
                byte[] secp224r1Seed = null;

                return new X9ECParameters(
                    secp224r1Curve,
                    secp224r1BasePoint,
                    secp224r1n,
                    secp224r1h,
                    secp224r1Seed);
            }
Example #18
0
 public virtual bool Equals(FpFieldElement other) =>
 (this.q.Equals(other.q) && base.Equals((ECFieldElement)other));
Example #19
0
 public FiniteFieldElement Multiply(BigInteger x)
 {
     var xInnerField = new FpFieldElement(this._field.Q, x.ToBouncyCastleBigInteger());
     var xAsFiniteFieldElement = new FiniteFieldElement(xInnerField);
     return Multiply(xAsFiniteFieldElement);
 }
Example #20
0
        public FpPoint Exctract(string ID, bool decrypt = false)
        {
            if (decrypt)
            {
                string sStr = File.ReadAllText("mk");
                s = int.Parse(sStr);
            }

            //  y^2 = x^3 + 117050x^2 + x
            BigInteger x = GeneralFunctions.H1hash(ID, p);
            BigInteger y = x.Pow(3).Add(x.Pow(2).Multiply(new BigInteger("117050", 10))).Add(x).Pow(2).ModInverse(p);

            FpFieldElement x_Qid = new FpFieldElement(q, x);
            FpFieldElement y_Qid = new FpFieldElement(q, y);
            FpPoint Qid = new FpPoint(E, x_Qid, y_Qid);

            FpPoint d_id = (FpPoint)Qid.Multiply(new BigInteger(s.ToString(), 10));

            // privatni ključ
            return d_id;
        }
Example #21
0
            protected override X9ECParameters CreateParameters()
            {
                // p = 2^256 - 2^224 + 2^192 + 2^96 - 1
                BigInteger secp256r1P = new BigInteger(
                    "115792089210356248762697446949407573530086143415290314195533631308867097853951");

                // a = -3, b = 5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b
                ECCurve secp256r1Curve = new FpCurve(secp256r1P,
                    new BigInteger("115792089210356248762697446949407573530086143415290314195533631308867097853948"),
                    new BigInteger("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", 16));

                // x = 6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296
                ECFieldElement secp256r1x = new FpFieldElement(
                    secp256r1P,
                    new BigInteger("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", 16));

                // y = 4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5
                ECFieldElement secp256r1y = new FpFieldElement(
                    secp256r1P,
                    new BigInteger("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5", 16));

                ECPoint secp256r1BasePoint = new FpPoint(
                    secp256r1Curve, secp256r1x, secp256r1y, false);

                BigInteger secp256r1n = new BigInteger("115792089210356248762697446949407573529996955224135760342422259061068512044369");

                BigInteger secp256r1h = new BigInteger("1");

                //static readonly byte[] secp256r1Seed = (Hex.decode("c49d360886e704936a6678e1139d26b7819f7e90"));
                byte[] secp256r1Seed = null;

                return new X9ECParameters(
                    secp256r1Curve,
                    secp256r1BasePoint,
                    secp256r1n,
                    secp256r1h,
                    secp256r1Seed);
            }
Example #22
0
 public FiniteFieldElement(BigInteger value, BigInteger prime)
 {
     Org.BouncyCastle.Math.BigInteger bouncy_q = prime.ToBouncyCastleBigInteger();
     Org.BouncyCastle.Math.BigInteger bouncy_x = value.ToBouncyCastleBigInteger();
     _field = new FpFieldElement(bouncy_q, bouncy_x);
 }
Example #23
0
		protected bool Equals(
			FpFieldElement other)
		{
			return q.Equals(other.q) && base.Equals(other);
		}
Example #24
0
            protected override X9ECParameters CreateParameters()
            {
                // p = 2^384 - 2^128 - 2^96 + 2^32 - 1
                BigInteger secp384r1P = new BigInteger(
                    "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFF", 16);

                // a, b
                ECCurve secp384r1Curve = new FpCurve(secp384r1P,
                    new BigInteger("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFC", 16),
                    new BigInteger("B3312FA7E23EE7E4988E056BE3F82D19181D9C6EFE8141120314088F5013875AC656398D8A2ED19D2A85C8EDD3EC2AEF", 16));

                // x
                ECFieldElement secp384r1x = new FpFieldElement(
                    secp384r1P,
                    new BigInteger("AA87CA22BE8B05378EB1C71EF320AD746E1D3B628BA79B9859F741E082542A385502F25DBF55296C3A545E3872760AB7", 16));

                // y
                ECFieldElement secp384r1y = new FpFieldElement(
                    secp384r1P,
                    new BigInteger("3617DE4A96262C6F5D9E98BF9292DC29F8F41DBD289A147CE9DA3113B5F0B8C00A60B1CE1D7E819D7A431D7C90EA0E5F", 16));

                ECPoint secp384r1BasePoint = new FpPoint(
                    secp384r1Curve, secp384r1x, secp384r1y, false);

                BigInteger secp384r1n = new BigInteger("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFC7634D81F4372DDF581A0DB248B0A77AECEC196ACCC52973", 16);

                BigInteger secp384r1h = BigInteger.One;

                //static readonly byte[] secp384r1Seed = (Hex.decode("A335926AA319A27A1D00896A6773A4827ACDAC73"));
                byte[] secp384r1Seed = null;

                return new X9ECParameters(
                    secp384r1Curve,
                    secp384r1BasePoint,
                    secp384r1n,
                    secp384r1h,
                    secp384r1Seed);
            }
Example #25
0
 public virtual bool Equals(
     FpFieldElement other)
 {
     return(q.Equals(other.q) && base.Equals(other));
 }
Example #26
0
            protected override X9ECParameters CreateParameters()
            {
                // p = 2^521 - 1
                BigInteger secp521r1P = new BigInteger(
                    "6864797660130609714981900799081393217269435300143305409394463459185543183397656052122559640661454554977296311391480858037121987999716643812574028291115057151");

                // a = -3, b = 051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00
                ECCurve secp521r1Curve = new FpCurve(secp521r1P,
                    new BigInteger("6864797660130609714981900799081393217269435300143305409394463459185543183397656052122559640661454554977296311391480858037121987999716643812574028291115057148"),
                    new BigInteger("051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00", 16));

                // x = c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66
                ECFieldElement secp521r1x = new FpFieldElement(
                    secp521r1P,
                    new BigInteger("c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66", 16));

                // y = 11839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650
                ECFieldElement secp521r1y = new FpFieldElement(
                    secp521r1P,
                    new BigInteger("11839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650", 16));

                ECPoint secp521r1BasePoint = new FpPoint(
                    secp521r1Curve, secp521r1x, secp521r1y, false);

                BigInteger secp521r1n = new BigInteger("6864797660130609714981900799081393217269435300143305409394463459185543183397655394245057746333217197532963996371363321113864768612440380340372808892707005449");

                BigInteger secp521r1h = new BigInteger("1");

                //static readonly byte[] secp521r1Seed = (Hex.decode("d09e8800291cb85396cc6717393284aaa0da64ba"));
                byte[] secp521r1Seed = null;

                return new X9ECParameters(
                    secp521r1Curve,
                    secp521r1BasePoint,
                    secp521r1n,
                    secp521r1h,
                    secp521r1Seed);
            }