Example #1
0
 public virtual bool Equals(SecT571FieldElement other)
 {
     if (this == other)
     {
         return(true);
     }
     if (null == other)
     {
         return(false);
     }
     return(Nat576.Eq64(x, other.x));
 }
Example #2
0
 public virtual bool Equals(SecT571FieldElement other)
 {
     return(this == other || (other != null && Nat576.Eq64(this.x, other.x)));
 }
Example #3
0
        public override ECPoint Add(ECPoint b)
        {
            if (this.IsInfinity)
            {
                return(b);
            }
            if (b.IsInfinity)
            {
                return(this);
            }

            ECCurve curve = this.Curve;

            SecT571FieldElement X1 = (SecT571FieldElement)this.RawXCoord;
            SecT571FieldElement X2 = (SecT571FieldElement)b.RawXCoord;

            if (X1.IsZero)
            {
                if (X2.IsZero)
                {
                    return(curve.Infinity);
                }

                return(b.Add(this));
            }

            SecT571FieldElement L1 = (SecT571FieldElement)this.RawYCoord, Z1 = (SecT571FieldElement)this.RawZCoords[0];
            SecT571FieldElement L2 = (SecT571FieldElement)b.RawYCoord, Z2 = (SecT571FieldElement)b.RawZCoords[0];

            ulong[] t1 = Nat576.Create64();
            ulong[] t2 = Nat576.Create64();
            ulong[] t3 = Nat576.Create64();
            ulong[] t4 = Nat576.Create64();

            ulong[] Z1Precomp = Z1.IsOne ? null : SecT571Field.PrecompMultiplicand(Z1.x);
            ulong[] U2, S2;
            if (Z1Precomp == null)
            {
                U2 = X2.x;
                S2 = L2.x;
            }
            else
            {
                SecT571Field.MultiplyPrecomp(X2.x, Z1Precomp, U2 = t2);
                SecT571Field.MultiplyPrecomp(L2.x, Z1Precomp, S2 = t4);
            }

            ulong[] Z2Precomp = Z2.IsOne ? null : SecT571Field.PrecompMultiplicand(Z2.x);
            ulong[] U1, S1;
            if (Z2Precomp == null)
            {
                U1 = X1.x;
                S1 = L1.x;
            }
            else
            {
                SecT571Field.MultiplyPrecomp(X1.x, Z2Precomp, U1 = t1);
                SecT571Field.MultiplyPrecomp(L1.x, Z2Precomp, S1 = t3);
            }

            ulong[] A = t3;
            SecT571Field.Add(S1, S2, A);

            ulong[] B = t4;
            SecT571Field.Add(U1, U2, B);

            if (Nat576.IsZero64(B))
            {
                if (Nat576.IsZero64(A))
                {
                    return(Twice());
                }

                return(curve.Infinity);
            }

            SecT571FieldElement X3, L3, Z3;

            if (X2.IsZero)
            {
                // TODO This can probably be optimized quite a bit
                ECPoint p = this.Normalize();
                X1 = (SecT571FieldElement)p.XCoord;
                ECFieldElement Y1 = p.YCoord;

                ECFieldElement Y2 = L2;
                ECFieldElement L  = Y1.Add(Y2).Divide(X1);

                X3 = (SecT571FieldElement)L.Square().Add(L).Add(X1).AddOne();
                if (X3.IsZero)
                {
                    return(new SecT571R1Point(curve, X3, SecT571R1Curve.SecT571R1_B_SQRT, IsCompressed));
                }

                ECFieldElement Y3 = L.Multiply(X1.Add(X3)).Add(X3).Add(Y1);
                L3 = (SecT571FieldElement)Y3.Divide(X3).Add(X3);
                Z3 = (SecT571FieldElement)curve.FromBigInteger(BigInteger.One);
            }
            else
            {
                SecT571Field.Square(B, B);

                ulong[] APrecomp = SecT571Field.PrecompMultiplicand(A);

                ulong[] AU1 = t1;
                ulong[] AU2 = t2;

                SecT571Field.MultiplyPrecomp(U1, APrecomp, AU1);
                SecT571Field.MultiplyPrecomp(U2, APrecomp, AU2);

                X3 = new SecT571FieldElement(t1);
                SecT571Field.Multiply(AU1, AU2, X3.x);

                if (X3.IsZero)
                {
                    return(new SecT571R1Point(curve, X3, SecT571R1Curve.SecT571R1_B_SQRT, IsCompressed));
                }

                Z3 = new SecT571FieldElement(t3);
                SecT571Field.MultiplyPrecomp(B, APrecomp, Z3.x);

                if (Z2Precomp != null)
                {
                    SecT571Field.MultiplyPrecomp(Z3.x, Z2Precomp, Z3.x);
                }

                ulong[] tt = Nat576.CreateExt64();

                SecT571Field.Add(AU2, B, t4);
                SecT571Field.SquareAddToExt(t4, tt);

                SecT571Field.Add(L1.x, Z1.x, t4);
                SecT571Field.MultiplyAddToExt(t4, Z3.x, tt);

                L3 = new SecT571FieldElement(t4);
                SecT571Field.Reduce(tt, L3.x);

                if (Z1Precomp != null)
                {
                    SecT571Field.MultiplyPrecomp(Z3.x, Z1Precomp, Z3.x);
                }
            }

            return(new SecT571R1Point(curve, X3, L3, new ECFieldElement[] { Z3 }, IsCompressed));
        }
Example #4
0
        public override ECPoint Twice()
        {
            if (this.IsInfinity)
            {
                return(this);
            }

            ECCurve curve = this.Curve;

            SecT571FieldElement X1 = (SecT571FieldElement)this.RawXCoord;

            if (X1.IsZero)
            {
                // A point with X == 0 is its own additive inverse
                return(curve.Infinity);
            }

            SecT571FieldElement L1 = (SecT571FieldElement)this.RawYCoord, Z1 = (SecT571FieldElement)this.RawZCoords[0];

            ulong[] t1 = Nat576.Create64();
            ulong[] t2 = Nat576.Create64();

            ulong[] Z1Precomp = Z1.IsOne ? null : SecT571Field.PrecompMultiplicand(Z1.x);
            ulong[] L1Z1, Z1Sq;
            if (Z1Precomp == null)
            {
                L1Z1 = L1.x;
                Z1Sq = Z1.x;
            }
            else
            {
                SecT571Field.MultiplyPrecomp(L1.x, Z1Precomp, L1Z1 = t1);
                SecT571Field.Square(Z1.x, Z1Sq = t2);
            }

            ulong[] T = Nat576.Create64();
            SecT571Field.Square(L1.x, T);
            SecT571Field.AddBothTo(L1Z1, Z1Sq, T);

            if (Nat576.IsZero64(T))
            {
                return(new SecT571R1Point(curve, new SecT571FieldElement(T), SecT571R1Curve.SecT571R1_B_SQRT, IsCompressed));
            }

            ulong[] tt = Nat576.CreateExt64();
            SecT571Field.MultiplyAddToExt(T, L1Z1, tt);

            SecT571FieldElement X3 = new SecT571FieldElement(t1);

            SecT571Field.Square(T, X3.x);

            SecT571FieldElement Z3 = new SecT571FieldElement(T);

            if (Z1Precomp != null)
            {
                SecT571Field.Multiply(Z3.x, Z1Sq, Z3.x);
            }

            ulong[] X1Z1;
            if (Z1Precomp == null)
            {
                X1Z1 = X1.x;
            }
            else
            {
                SecT571Field.MultiplyPrecomp(X1.x, Z1Precomp, X1Z1 = t2);
            }

            SecT571Field.SquareAddToExt(X1Z1, tt);
            SecT571Field.Reduce(tt, t2);
            SecT571Field.AddBothTo(X3.x, Z3.x, t2);
            SecT571FieldElement L3 = new SecT571FieldElement(t2);

            return(new SecT571R1Point(curve, X3, L3, new ECFieldElement[] { Z3 }, IsCompressed));
        }
 public virtual bool Equals(SecT571FieldElement other)
 {
     if (this == other)
         return true;
     if (null == other)
         return false;
     return Nat576.Eq64(x, other.x);
 }