Example #1
0
 public static void AddOne(uint[] x, uint[] z)
 {
     if (Nat.Inc(4, x, z) != 0u || (z[3] == 4294967293u && Nat128.Gte(z, SecP128R1Field.P)))
     {
         SecP128R1Field.AddPInvTo(z);
     }
 }
 public override ECFieldElement Sqrt()
 {
     uint[] x = this.x;
     if (Nat128.IsZero(x) || Nat128.IsOne(x))
     {
         return(this);
     }
     uint[] z = Nat128.Create();
     SecP128R1Field.Square(x, z);
     SecP128R1Field.Multiply(z, x, z);
     uint[] numArray3 = Nat128.Create();
     SecP128R1Field.SquareN(z, 2, numArray3);
     SecP128R1Field.Multiply(numArray3, z, numArray3);
     uint[] numArray4 = Nat128.Create();
     SecP128R1Field.SquareN(numArray3, 4, numArray4);
     SecP128R1Field.Multiply(numArray4, numArray3, numArray4);
     uint[] numArray5 = numArray3;
     SecP128R1Field.SquareN(numArray4, 2, numArray5);
     SecP128R1Field.Multiply(numArray5, z, numArray5);
     uint[] numArray6 = z;
     SecP128R1Field.SquareN(numArray5, 10, numArray6);
     SecP128R1Field.Multiply(numArray6, numArray5, numArray6);
     uint[] numArray7 = numArray4;
     SecP128R1Field.SquareN(numArray6, 10, numArray7);
     SecP128R1Field.Multiply(numArray7, numArray5, numArray7);
     uint[] numArray8 = numArray5;
     SecP128R1Field.Square(numArray7, numArray8);
     SecP128R1Field.Multiply(numArray8, x, numArray8);
     uint[] numArray9 = numArray8;
     SecP128R1Field.SquareN(numArray9, 0x5f, numArray9);
     uint[] numArray10 = numArray7;
     SecP128R1Field.Square(numArray9, numArray10);
     return(!Nat128.Eq(x, numArray10) ? null : new SecP128R1FieldElement(numArray9));
 }
Example #3
0
 public override ECFieldElement Divide(ECFieldElement b)
 {
     uint[] z = Nat128.Create();
     Mod.Invert(SecP128R1Field.P, ((SecP128R1FieldElement)b).x, z);
     SecP128R1Field.Multiply(z, x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #4
0
        public static void Reduce(uint[] xx, uint[] z)
        {
            ulong num  = (ulong)xx[0];
            ulong num2 = (ulong)xx[1];
            ulong num3 = (ulong)xx[2];
            ulong num4 = (ulong)xx[3];
            ulong num5 = (ulong)xx[4];
            ulong num6 = (ulong)xx[5];
            ulong num7 = (ulong)xx[6];
            ulong num8 = (ulong)xx[7];

            num4 += num8;
            num7 += num8 << 1;
            num3 += num7;
            num6 += num7 << 1;
            num2 += num6;
            num5 += num6 << 1;
            num  += num5;
            num4 += num5 << 1;
            z[0]  = (uint)num;
            num2 += num >> 32;
            z[1]  = (uint)num2;
            num3 += num2 >> 32;
            z[2]  = (uint)num3;
            num4 += num3 >> 32;
            z[3]  = (uint)num4;
            SecP128R1Field.Reduce32((uint)(num4 >> 32), z);
        }
 public override ECFieldElement Sqrt()
 {
     uint[] y = x;
     if (Nat128.IsZero(y) || Nat128.IsOne(y))
     {
         return(this);
     }
     uint[] array = Nat128.Create();
     SecP128R1Field.Square(y, array);
     SecP128R1Field.Multiply(array, y, array);
     uint[] array2 = Nat128.Create();
     SecP128R1Field.SquareN(array, 2, array2);
     SecP128R1Field.Multiply(array2, array, array2);
     uint[] array3 = Nat128.Create();
     SecP128R1Field.SquareN(array2, 4, array3);
     SecP128R1Field.Multiply(array3, array2, array3);
     uint[] array4 = array2;
     SecP128R1Field.SquareN(array3, 2, array4);
     SecP128R1Field.Multiply(array4, array, array4);
     uint[] z = array;
     SecP128R1Field.SquareN(array4, 10, z);
     SecP128R1Field.Multiply(z, array4, z);
     uint[] array5 = array3;
     SecP128R1Field.SquareN(z, 10, array5);
     SecP128R1Field.Multiply(array5, array4, array5);
     uint[] array6 = array4;
     SecP128R1Field.Square(array5, array6);
     SecP128R1Field.Multiply(array6, y, array6);
     uint[] z2 = array6;
     SecP128R1Field.SquareN(z2, 95, z2);
     uint[] array7 = array5;
     SecP128R1Field.Square(z2, array7);
     return((!Nat128.Eq(y, array7)) ? null : new SecP128R1FieldElement(z2));
 }
 public override ECFieldElement Invert()
 {
     //        return new SecP128R1FieldElement(toBigInteger().modInverse(Q));
     uint[] z = Nat128.Create();
     SecP128R1Field.Inv(x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #7
0
 public static void Twice(uint[] x, uint[] z)
 {
     if (Nat.ShiftUpBit(4, x, 0u, z) != 0u || (z[3] == 4294967293u && Nat128.Gte(z, SecP128R1Field.P)))
     {
         SecP128R1Field.AddPInvTo(z);
     }
 }
 public override ECFieldElement Divide(ECFieldElement b)
 {
     //        return multiply(b.invert());
     uint[] z = Nat128.Create();
     SecP128R1Field.Inv(((SecP128R1FieldElement)b).x, z);
     SecP128R1Field.Multiply(z, x, z);
     return(new SecP128R1FieldElement(z));
 }
 public SecP128R1FieldElement(BigInteger x)
 {
     if (x == null || x.SignValue < 0 || x.CompareTo(Q) >= 0)
     {
         throw new ArgumentException("value invalid for SecP128R1FieldElement", "x");
     }
     this.x = SecP128R1Field.FromBigInteger(x);
 }
Example #10
0
        public override ECPoint Twice()
        {
            if (base.IsInfinity)
            {
                return(this);
            }
            ECCurve curve = this.Curve;
            SecP128R1FieldElement rawYCoord = (SecP128R1FieldElement)base.RawYCoord;

            if (rawYCoord.IsZero)
            {
                return(curve.Infinity);
            }
            SecP128R1FieldElement rawXCoord = (SecP128R1FieldElement)base.RawXCoord;
            SecP128R1FieldElement element3  = (SecP128R1FieldElement)base.RawZCoords[0];

            uint[] z         = Nat128.Create();
            uint[] numArray2 = Nat128.Create();
            uint[] numArray3 = Nat128.Create();
            SecP128R1Field.Square(rawYCoord.x, numArray3);
            uint[] numArray4 = Nat128.Create();
            SecP128R1Field.Square(numArray3, numArray4);
            bool isOne = element3.IsOne;

            uint[] x = element3.x;
            if (!isOne)
            {
                x = numArray2;
                SecP128R1Field.Square(element3.x, x);
            }
            SecP128R1Field.Subtract(rawXCoord.x, x, z);
            uint[] numArray6 = numArray2;
            SecP128R1Field.Add(rawXCoord.x, x, numArray6);
            SecP128R1Field.Multiply(numArray6, z, numArray6);
            SecP128R1Field.Reduce32(Nat128.AddBothTo(numArray6, numArray6, numArray6), numArray6);
            uint[] numArray7 = numArray3;
            SecP128R1Field.Multiply(numArray3, rawXCoord.x, numArray7);
            SecP128R1Field.Reduce32(Nat.ShiftUpBits(4, numArray7, 2, 0), numArray7);
            SecP128R1Field.Reduce32(Nat.ShiftUpBits(4, numArray4, 3, 0, z), z);
            SecP128R1FieldElement element4 = new SecP128R1FieldElement(numArray4);

            SecP128R1Field.Square(numArray6, element4.x);
            SecP128R1Field.Subtract(element4.x, numArray7, element4.x);
            SecP128R1Field.Subtract(element4.x, numArray7, element4.x);
            SecP128R1FieldElement y = new SecP128R1FieldElement(numArray7);

            SecP128R1Field.Subtract(numArray7, element4.x, y.x);
            SecP128R1Field.Multiply(y.x, numArray6, y.x);
            SecP128R1Field.Subtract(y.x, z, y.x);
            SecP128R1FieldElement element6 = new SecP128R1FieldElement(numArray6);

            SecP128R1Field.Twice(rawYCoord.x, element6.x);
            if (!isOne)
            {
                SecP128R1Field.Multiply(element6.x, element3.x, element6.x);
            }
            return(new SecP128R1Point(curve, element4, y, new ECFieldElement[] { element6 }, base.IsCompressed));
        }
Example #11
0
        public static void Subtract(uint[] x, uint[] y, uint[] z)
        {
            int num = Nat128.Sub(x, y, z);

            if (num != 0)
            {
                SecP128R1Field.SubPInvFrom(z);
            }
        }
Example #12
0
 public SecP128R1FieldElement(BigInteger x)
 {
     //IL_002a: Unknown result type (might be due to invalid IL or missing references)
     if (x == null || x.SignValue < 0 || x.CompareTo(Q) >= 0)
     {
         throw new ArgumentException("value invalid for SecP128R1FieldElement", "x");
     }
     this.x = SecP128R1Field.FromBigInteger(x);
 }
Example #13
0
 public static void SquareN(uint[] x, int n, uint[] z)
 {
     uint[] array = Nat128.CreateExt();
     Nat128.Square(x, array);
     SecP128R1Field.Reduce(array, z);
     while (--n > 0)
     {
         Nat128.Square(z, array);
         SecP128R1Field.Reduce(array, z);
     }
 }
Example #14
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()
        {
            /*
             * Raise this element to the exponent 2^126 - 2^95
             *
             * Breaking up the exponent's binary representation into "repunits", we get:
             *     { 31 1s } { 95 0s }
             *
             * Therefore we need an addition chain containing 31 (the length of the repunit) We use:
             *     1, 2, 4, 8, 10, 20, 30, [31]
             */

            uint[] x1 = this.x;
            if (Nat128.IsZero(x1) || Nat128.IsOne(x1))
            {
                return(this);
            }

            uint[] x2 = Nat128.Create();
            SecP128R1Field.Square(x1, x2);
            SecP128R1Field.Multiply(x2, x1, x2);
            uint[] x4 = Nat128.Create();
            SecP128R1Field.SquareN(x2, 2, x4);
            SecP128R1Field.Multiply(x4, x2, x4);
            uint[] x8 = Nat128.Create();
            SecP128R1Field.SquareN(x4, 4, x8);
            SecP128R1Field.Multiply(x8, x4, x8);
            uint[] x10 = x4;
            SecP128R1Field.SquareN(x8, 2, x10);
            SecP128R1Field.Multiply(x10, x2, x10);
            uint[] x20 = x2;
            SecP128R1Field.SquareN(x10, 10, x20);
            SecP128R1Field.Multiply(x20, x10, x20);
            uint[] x30 = x8;
            SecP128R1Field.SquareN(x20, 10, x30);
            SecP128R1Field.Multiply(x30, x10, x30);
            uint[] x31 = x10;
            SecP128R1Field.Square(x30, x31);
            SecP128R1Field.Multiply(x31, x1, x31);

            uint[] t1 = x31;
            SecP128R1Field.SquareN(t1, 95, t1);

            uint[] t2 = x30;
            SecP128R1Field.Square(t1, t2);

            return(Nat128.Eq(x1, t2) ? new SecP128R1FieldElement(t1) : null);
        }
Example #15
0
        public override ECPoint Twice()
        {
            if (base.IsInfinity)
            {
                return(this);
            }
            ECCurve curve = Curve;
            SecP128R1FieldElement secP128R1FieldElement = (SecP128R1FieldElement)base.RawYCoord;

            if (secP128R1FieldElement.IsZero)
            {
                return(curve.Infinity);
            }
            SecP128R1FieldElement secP128R1FieldElement2 = (SecP128R1FieldElement)base.RawXCoord;
            SecP128R1FieldElement secP128R1FieldElement3 = (SecP128R1FieldElement)base.RawZCoords[0];

            uint[] array  = Nat128.Create();
            uint[] array2 = Nat128.Create();
            uint[] array3 = Nat128.Create();
            SecP128R1Field.Square(secP128R1FieldElement.x, array3);
            uint[] array4 = Nat128.Create();
            SecP128R1Field.Square(array3, array4);
            bool isOne = secP128R1FieldElement3.IsOne;

            uint[] array5 = secP128R1FieldElement3.x;
            if (!isOne)
            {
                array5 = array2;
                SecP128R1Field.Square(secP128R1FieldElement3.x, array5);
            }
            SecP128R1Field.Subtract(secP128R1FieldElement2.x, array5, array);
            uint[] array6 = array2;
            SecP128R1Field.Add(secP128R1FieldElement2.x, array5, array6);
            SecP128R1Field.Multiply(array6, array, array6);
            uint x = Nat128.AddBothTo(array6, array6, array6);

            SecP128R1Field.Reduce32(x, array6);
            uint[] array7 = array3;
            SecP128R1Field.Multiply(array3, secP128R1FieldElement2.x, array7);
            x = Nat.ShiftUpBits(4, array7, 2, 0u);
            SecP128R1Field.Reduce32(x, array7);
            x = Nat.ShiftUpBits(4, array4, 3, 0u, array);
            SecP128R1Field.Reduce32(x, array);
            SecP128R1FieldElement secP128R1FieldElement4 = new SecP128R1FieldElement(array4);

            SecP128R1Field.Square(array6, secP128R1FieldElement4.x);
            SecP128R1Field.Subtract(secP128R1FieldElement4.x, array7, secP128R1FieldElement4.x);
            SecP128R1Field.Subtract(secP128R1FieldElement4.x, array7, secP128R1FieldElement4.x);
            SecP128R1FieldElement secP128R1FieldElement5 = new SecP128R1FieldElement(array7);

            SecP128R1Field.Subtract(array7, secP128R1FieldElement4.x, secP128R1FieldElement5.x);
            SecP128R1Field.Multiply(secP128R1FieldElement5.x, array6, secP128R1FieldElement5.x);
            SecP128R1Field.Subtract(secP128R1FieldElement5.x, array, secP128R1FieldElement5.x);
            SecP128R1FieldElement secP128R1FieldElement6 = new SecP128R1FieldElement(array6);

            SecP128R1Field.Twice(secP128R1FieldElement.x, secP128R1FieldElement6.x);
            if (!isOne)
            {
                SecP128R1Field.Multiply(secP128R1FieldElement6.x, secP128R1FieldElement3.x, secP128R1FieldElement6.x);
            }
            return(new SecP128R1Point(curve, secP128R1FieldElement4, secP128R1FieldElement5, new ECFieldElement[1] {
                secP128R1FieldElement6
            }, base.IsCompressed));
        }
Example #16
0
        public override ECPoint Add(ECPoint b)
        {
            if (base.IsInfinity)
            {
                return(b);
            }
            if (b.IsInfinity)
            {
                return(this);
            }
            if (this == b)
            {
                return(Twice());
            }
            ECCurve curve = Curve;
            SecP128R1FieldElement secP128R1FieldElement  = (SecP128R1FieldElement)base.RawXCoord;
            SecP128R1FieldElement secP128R1FieldElement2 = (SecP128R1FieldElement)base.RawYCoord;
            SecP128R1FieldElement secP128R1FieldElement3 = (SecP128R1FieldElement)b.RawXCoord;
            SecP128R1FieldElement secP128R1FieldElement4 = (SecP128R1FieldElement)b.RawYCoord;
            SecP128R1FieldElement secP128R1FieldElement5 = (SecP128R1FieldElement)base.RawZCoords[0];
            SecP128R1FieldElement secP128R1FieldElement6 = (SecP128R1FieldElement)b.RawZCoords[0];

            uint[] array  = Nat128.CreateExt();
            uint[] array2 = Nat128.Create();
            uint[] array3 = Nat128.Create();
            uint[] array4 = Nat128.Create();
            bool   isOne  = secP128R1FieldElement5.IsOne;

            uint[] array5;
            uint[] array6;
            if (isOne)
            {
                array5 = secP128R1FieldElement3.x;
                array6 = secP128R1FieldElement4.x;
            }
            else
            {
                array6 = array3;
                SecP128R1Field.Square(secP128R1FieldElement5.x, array6);
                array5 = array2;
                SecP128R1Field.Multiply(array6, secP128R1FieldElement3.x, array5);
                SecP128R1Field.Multiply(array6, secP128R1FieldElement5.x, array6);
                SecP128R1Field.Multiply(array6, secP128R1FieldElement4.x, array6);
            }
            bool isOne2 = secP128R1FieldElement6.IsOne;

            uint[] array7;
            uint[] array8;
            if (isOne2)
            {
                array7 = secP128R1FieldElement.x;
                array8 = secP128R1FieldElement2.x;
            }
            else
            {
                array8 = array4;
                SecP128R1Field.Square(secP128R1FieldElement6.x, array8);
                array7 = array;
                SecP128R1Field.Multiply(array8, secP128R1FieldElement.x, array7);
                SecP128R1Field.Multiply(array8, secP128R1FieldElement6.x, array8);
                SecP128R1Field.Multiply(array8, secP128R1FieldElement2.x, array8);
            }
            uint[] array9 = Nat128.Create();
            SecP128R1Field.Subtract(array7, array5, array9);
            uint[] array10 = array2;
            SecP128R1Field.Subtract(array8, array6, array10);
            if (Nat128.IsZero(array9))
            {
                if (Nat128.IsZero(array10))
                {
                    return(Twice());
                }
                return(curve.Infinity);
            }
            uint[] array11 = array3;
            SecP128R1Field.Square(array9, array11);
            uint[] array12 = Nat128.Create();
            SecP128R1Field.Multiply(array11, array9, array12);
            uint[] array13 = array3;
            SecP128R1Field.Multiply(array11, array7, array13);
            SecP128R1Field.Negate(array12, array12);
            Nat128.Mul(array8, array12, array);
            uint x = Nat128.AddBothTo(array13, array13, array12);

            SecP128R1Field.Reduce32(x, array12);
            SecP128R1FieldElement secP128R1FieldElement7 = new SecP128R1FieldElement(array4);

            SecP128R1Field.Square(array10, secP128R1FieldElement7.x);
            SecP128R1Field.Subtract(secP128R1FieldElement7.x, array12, secP128R1FieldElement7.x);
            SecP128R1FieldElement secP128R1FieldElement8 = new SecP128R1FieldElement(array12);

            SecP128R1Field.Subtract(array13, secP128R1FieldElement7.x, secP128R1FieldElement8.x);
            SecP128R1Field.MultiplyAddToExt(secP128R1FieldElement8.x, array10, array);
            SecP128R1Field.Reduce(array, secP128R1FieldElement8.x);
            SecP128R1FieldElement secP128R1FieldElement9 = new SecP128R1FieldElement(array9);

            if (!isOne)
            {
                SecP128R1Field.Multiply(secP128R1FieldElement9.x, secP128R1FieldElement5.x, secP128R1FieldElement9.x);
            }
            if (!isOne2)
            {
                SecP128R1Field.Multiply(secP128R1FieldElement9.x, secP128R1FieldElement6.x, secP128R1FieldElement9.x);
            }
            ECFieldElement[] zs = new ECFieldElement[1] {
                secP128R1FieldElement9
            };
            return(new SecP128R1Point(curve, secP128R1FieldElement7, secP128R1FieldElement8, zs, base.IsCompressed));
        }
Example #17
0
 public static void Square(uint[] x, uint[] z)
 {
     uint[] array = Nat128.CreateExt();
     Nat128.Square(x, array);
     SecP128R1Field.Reduce(array, z);
 }
Example #18
0
        public override ECPoint Add(ECPoint b)
        {
            uint[] numArray5;
            uint[] numArray6;
            uint[] numArray7;
            uint[] numArray8;
            if (base.IsInfinity)
            {
                return(b);
            }
            if (b.IsInfinity)
            {
                return(this);
            }
            if (this == b)
            {
                return(this.Twice());
            }
            ECCurve curve = this.Curve;
            SecP128R1FieldElement rawXCoord = (SecP128R1FieldElement)base.RawXCoord;
            SecP128R1FieldElement rawYCoord = (SecP128R1FieldElement)base.RawYCoord;
            SecP128R1FieldElement element3  = (SecP128R1FieldElement)b.RawXCoord;
            SecP128R1FieldElement element4  = (SecP128R1FieldElement)b.RawYCoord;
            SecP128R1FieldElement element5  = (SecP128R1FieldElement)base.RawZCoords[0];
            SecP128R1FieldElement element6  = (SecP128R1FieldElement)b.RawZCoords[0];

            uint[] zz        = Nat128.CreateExt();
            uint[] numArray2 = Nat128.Create();
            uint[] numArray3 = Nat128.Create();
            uint[] x         = Nat128.Create();
            bool   isOne     = element5.IsOne;

            if (isOne)
            {
                numArray5 = element3.x;
                numArray6 = element4.x;
            }
            else
            {
                numArray6 = numArray3;
                SecP128R1Field.Square(element5.x, numArray6);
                numArray5 = numArray2;
                SecP128R1Field.Multiply(numArray6, element3.x, numArray5);
                SecP128R1Field.Multiply(numArray6, element5.x, numArray6);
                SecP128R1Field.Multiply(numArray6, element4.x, numArray6);
            }
            bool flag2 = element6.IsOne;

            if (flag2)
            {
                numArray7 = rawXCoord.x;
                numArray8 = rawYCoord.x;
            }
            else
            {
                numArray8 = x;
                SecP128R1Field.Square(element6.x, numArray8);
                numArray7 = zz;
                SecP128R1Field.Multiply(numArray8, rawXCoord.x, numArray7);
                SecP128R1Field.Multiply(numArray8, element6.x, numArray8);
                SecP128R1Field.Multiply(numArray8, rawYCoord.x, numArray8);
            }
            uint[] z = Nat128.Create();
            SecP128R1Field.Subtract(numArray7, numArray5, z);
            uint[] numArray10 = numArray2;
            SecP128R1Field.Subtract(numArray8, numArray6, numArray10);
            if (Nat128.IsZero(z))
            {
                if (Nat128.IsZero(numArray10))
                {
                    return(this.Twice());
                }
                return(curve.Infinity);
            }
            uint[] numArray11 = numArray3;
            SecP128R1Field.Square(z, numArray11);
            uint[] numArray12 = Nat128.Create();
            SecP128R1Field.Multiply(numArray11, z, numArray12);
            uint[] numArray13 = numArray3;
            SecP128R1Field.Multiply(numArray11, numArray7, numArray13);
            SecP128R1Field.Negate(numArray12, numArray12);
            Nat128.Mul(numArray8, numArray12, zz);
            SecP128R1Field.Reduce32(Nat128.AddBothTo(numArray13, numArray13, numArray12), numArray12);
            SecP128R1FieldElement element7 = new SecP128R1FieldElement(x);

            SecP128R1Field.Square(numArray10, element7.x);
            SecP128R1Field.Subtract(element7.x, numArray12, element7.x);
            SecP128R1FieldElement y = new SecP128R1FieldElement(numArray12);

            SecP128R1Field.Subtract(numArray13, element7.x, y.x);
            SecP128R1Field.MultiplyAddToExt(y.x, numArray10, zz);
            SecP128R1Field.Reduce(zz, y.x);
            SecP128R1FieldElement element9 = new SecP128R1FieldElement(z);

            if (!isOne)
            {
                SecP128R1Field.Multiply(element9.x, element5.x, element9.x);
            }
            if (!flag2)
            {
                SecP128R1Field.Multiply(element9.x, element6.x, element9.x);
            }
            ECFieldElement[] zs = new ECFieldElement[] { element9 };
            return(new SecP128R1Point(curve, element7, y, zs, base.IsCompressed));
        }
        public override ECPoint Add(ECPoint b)
        {
            if (this.IsInfinity)
            {
                return(b);
            }
            if (b.IsInfinity)
            {
                return(this);
            }
            if (this == b)
            {
                return(Twice());
            }

            ECCurve curve = this.Curve;

            SecP128R1FieldElement X1 = (SecP128R1FieldElement)this.RawXCoord, Y1 = (SecP128R1FieldElement)this.RawYCoord;
            SecP128R1FieldElement X2 = (SecP128R1FieldElement)b.RawXCoord, Y2 = (SecP128R1FieldElement)b.RawYCoord;

            SecP128R1FieldElement Z1 = (SecP128R1FieldElement)this.RawZCoords[0];
            SecP128R1FieldElement Z2 = (SecP128R1FieldElement)b.RawZCoords[0];

            uint c;

            uint[] tt1 = Nat128.CreateExt();
            uint[] t2  = Nat128.Create();
            uint[] t3  = Nat128.Create();
            uint[] t4  = Nat128.Create();

            bool Z1IsOne = Z1.IsOne;

            uint[] U2, S2;
            if (Z1IsOne)
            {
                U2 = X2.x;
                S2 = Y2.x;
            }
            else
            {
                S2 = t3;
                SecP128R1Field.Square(Z1.x, S2);

                U2 = t2;
                SecP128R1Field.Multiply(S2, X2.x, U2);

                SecP128R1Field.Multiply(S2, Z1.x, S2);
                SecP128R1Field.Multiply(S2, Y2.x, S2);
            }

            bool Z2IsOne = Z2.IsOne;

            uint[] U1, S1;
            if (Z2IsOne)
            {
                U1 = X1.x;
                S1 = Y1.x;
            }
            else
            {
                S1 = t4;
                SecP128R1Field.Square(Z2.x, S1);

                U1 = tt1;
                SecP128R1Field.Multiply(S1, X1.x, U1);

                SecP128R1Field.Multiply(S1, Z2.x, S1);
                SecP128R1Field.Multiply(S1, Y1.x, S1);
            }

            uint[] H = Nat128.Create();
            SecP128R1Field.Subtract(U1, U2, H);

            uint[] R = t2;
            SecP128R1Field.Subtract(S1, S2, R);

            // Check if b == this or b == -this
            if (Nat128.IsZero(H))
            {
                if (Nat128.IsZero(R))
                {
                    // this == b, i.e. this must be doubled
                    return(this.Twice());
                }

                // this == -b, i.e. the result is the point at infinity
                return(curve.Infinity);
            }

            uint[] HSquared = t3;
            SecP128R1Field.Square(H, HSquared);

            uint[] G = Nat128.Create();
            SecP128R1Field.Multiply(HSquared, H, G);

            uint[] V = t3;
            SecP128R1Field.Multiply(HSquared, U1, V);

            SecP128R1Field.Negate(G, G);
            Nat128.Mul(S1, G, tt1);

            c = Nat128.AddBothTo(V, V, G);
            SecP128R1Field.Reduce32(c, G);

            SecP128R1FieldElement X3 = new SecP128R1FieldElement(t4);

            SecP128R1Field.Square(R, X3.x);
            SecP128R1Field.Subtract(X3.x, G, X3.x);

            SecP128R1FieldElement Y3 = new SecP128R1FieldElement(G);

            SecP128R1Field.Subtract(V, X3.x, Y3.x);
            SecP128R1Field.MultiplyAddToExt(Y3.x, R, tt1);
            SecP128R1Field.Reduce(tt1, Y3.x);

            SecP128R1FieldElement Z3 = new SecP128R1FieldElement(H);

            if (!Z1IsOne)
            {
                SecP128R1Field.Multiply(Z3.x, Z1.x, Z3.x);
            }
            if (!Z2IsOne)
            {
                SecP128R1Field.Multiply(Z3.x, Z2.x, Z3.x);
            }

            ECFieldElement[] zs = new ECFieldElement[] { Z3 };

            return(new SecP128R1Point(curve, X3, Y3, zs, IsCompressed));
        }
        public override ECPoint Twice()
        {
            if (this.IsInfinity)
            {
                return(this);
            }

            ECCurve curve = this.Curve;

            SecP128R1FieldElement Y1 = (SecP128R1FieldElement)this.RawYCoord;

            if (Y1.IsZero)
            {
                return(curve.Infinity);
            }

            SecP128R1FieldElement X1 = (SecP128R1FieldElement)this.RawXCoord, Z1 = (SecP128R1FieldElement)this.RawZCoords[0];

            uint c;

            uint[] t1 = Nat128.Create();
            uint[] t2 = Nat128.Create();

            uint[] Y1Squared = Nat128.Create();
            SecP128R1Field.Square(Y1.x, Y1Squared);

            uint[] T = Nat128.Create();
            SecP128R1Field.Square(Y1Squared, T);

            bool Z1IsOne = Z1.IsOne;

            uint[] Z1Squared = Z1.x;
            if (!Z1IsOne)
            {
                Z1Squared = t2;
                SecP128R1Field.Square(Z1.x, Z1Squared);
            }

            SecP128R1Field.Subtract(X1.x, Z1Squared, t1);

            uint[] M = t2;
            SecP128R1Field.Add(X1.x, Z1Squared, M);
            SecP128R1Field.Multiply(M, t1, M);
            c = Nat128.AddBothTo(M, M, M);
            SecP128R1Field.Reduce32(c, M);

            uint[] S = Y1Squared;
            SecP128R1Field.Multiply(Y1Squared, X1.x, S);
            c = Nat.ShiftUpBits(4, S, 2, 0);
            SecP128R1Field.Reduce32(c, S);

            c = Nat.ShiftUpBits(4, T, 3, 0, t1);
            SecP128R1Field.Reduce32(c, t1);

            SecP128R1FieldElement X3 = new SecP128R1FieldElement(T);

            SecP128R1Field.Square(M, X3.x);
            SecP128R1Field.Subtract(X3.x, S, X3.x);
            SecP128R1Field.Subtract(X3.x, S, X3.x);

            SecP128R1FieldElement Y3 = new SecP128R1FieldElement(S);

            SecP128R1Field.Subtract(S, X3.x, Y3.x);
            SecP128R1Field.Multiply(Y3.x, M, Y3.x);
            SecP128R1Field.Subtract(Y3.x, t1, Y3.x);

            SecP128R1FieldElement Z3 = new SecP128R1FieldElement(M);

            SecP128R1Field.Twice(Y1.x, Z3.x);
            if (!Z1IsOne)
            {
                SecP128R1Field.Multiply(Z3.x, Z1.x, Z3.x);
            }

            return(new SecP128R1Point(curve, X3, Y3, new ECFieldElement[] { Z3 }, IsCompressed));
        }
Example #21
0
 public override ECFieldElement Multiply(ECFieldElement b)
 {
     uint[] z = Nat128.Create();
     SecP128R1Field.Multiply(x, ((SecP128R1FieldElement)b).x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #22
0
 public override ECFieldElement AddOne()
 {
     uint[] z = Nat128.Create();
     SecP128R1Field.AddOne(x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #23
0
 public override ECFieldElement RandomFieldElement(SecureRandom r)
 {
     uint[] x = Nat128.Create();
     SecP128R1Field.Random(r, x);
     return(new SecP128R1FieldElement(x));
 }
Example #24
0
 public override ECFieldElement Square()
 {
     uint[] z = Nat128.Create();
     SecP128R1Field.Square(this.x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #25
0
 public static void Multiply(uint[] x, uint[] y, uint[] z)
 {
     uint[] array = Nat128.CreateExt();
     Nat128.Mul(x, y, array);
     SecP128R1Field.Reduce(array, z);
 }
Example #26
0
 public override ECFieldElement Subtract(ECFieldElement b)
 {
     uint[] z = Nat128.Create();
     SecP128R1Field.Subtract(x, ((SecP128R1FieldElement)b).x, z);
     return(new SecP128R1FieldElement(z));
 }
Example #27
0
 public override ECFieldElement Add(ECFieldElement b)
 {
     uint[] z = Nat128.Create();
     SecP128R1Field.Add(this.x, ((SecP128R1FieldElement)b).x, z);
     return(new SecP128R1FieldElement(z));
 }