diff options
Diffstat (limited to 'crypto/src')
| -rw-r--r-- | crypto/src/crypto/ec/CustomNamedCurves.cs | 23 | ||||
| -rw-r--r-- | crypto/src/math/ec/custom/sec/Nat384.cs | 46 | ||||
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP384R1Curve.cs | 95 | ||||
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP384R1Field.cs | 227 | ||||
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP384R1FieldElement.cs | 155 | ||||
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP384R1Point.cs | 287 |
6 files changed, 833 insertions, 0 deletions
diff --git a/crypto/src/crypto/ec/CustomNamedCurves.cs b/crypto/src/crypto/ec/CustomNamedCurves.cs index 7d6b00339..a4b21ab3d 100644 --- a/crypto/src/crypto/ec/CustomNamedCurves.cs +++ b/crypto/src/crypto/ec/CustomNamedCurves.cs @@ -156,6 +156,27 @@ namespace Org.BouncyCastle.Crypto.EC } /* + * secp384r1 + */ + internal class Secp384r1Holder + : X9ECParametersHolder + { + private Secp384r1Holder() { } + + internal static readonly X9ECParametersHolder Instance = new Secp384r1Holder(); + + protected override X9ECParameters CreateParameters() + { + byte[] S = Hex.Decode("A335926AA319A27A1D00896A6773A4827ACDAC73"); + ECCurve curve = ConfigureCurve(new SecP384R1Curve()); + ECPoint G = curve.DecodePoint(Hex.Decode("04" + + "AA87CA22BE8B05378EB1C71EF320AD746E1D3B628BA79B9859F741E082542A385502F25DBF55296C3A545E3872760AB7" + + "3617DE4A96262C6F5D9E98BF9292DC29F8F41DBD289A147CE9DA3113B5F0B8C00A60B1CE1D7E819D7A431D7C90EA0E5F")); + return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S); + } + } + + /* * secp521r1 */ internal class Secp521r1Holder @@ -195,11 +216,13 @@ namespace Org.BouncyCastle.Crypto.EC DefineCurve("secp224r1", SecObjectIdentifiers.SecP224r1, Secp224r1Holder.Instance); DefineCurve("secp256k1", SecObjectIdentifiers.SecP256k1, Secp256k1Holder.Instance); DefineCurve("secp256r1", SecObjectIdentifiers.SecP256r1, Secp256r1Holder.Instance); + DefineCurve("secp384r1", SecObjectIdentifiers.SecP384r1, Secp384r1Holder.Instance); DefineCurve("secp521r1", SecObjectIdentifiers.SecP521r1, Secp521r1Holder.Instance); objIds.Add(Platform.ToLowerInvariant("P-192"), SecObjectIdentifiers.SecP192r1); objIds.Add(Platform.ToLowerInvariant("P-224"), SecObjectIdentifiers.SecP224r1); objIds.Add(Platform.ToLowerInvariant("P-256"), SecObjectIdentifiers.SecP256r1); + objIds.Add(Platform.ToLowerInvariant("P-384"), SecObjectIdentifiers.SecP384r1); objIds.Add(Platform.ToLowerInvariant("P-521"), SecObjectIdentifiers.SecP521r1); } diff --git a/crypto/src/math/ec/custom/sec/Nat384.cs b/crypto/src/math/ec/custom/sec/Nat384.cs new file mode 100644 index 000000000..273ee2d65 --- /dev/null +++ b/crypto/src/math/ec/custom/sec/Nat384.cs @@ -0,0 +1,46 @@ +using System; +using System.Diagnostics; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal abstract class Nat384 + { + public static void Mul(uint[] x, uint[] y, uint[] zz) + { + Nat192.Mul(x, y, zz); + Nat192.Mul(x, 6, y, 6, zz, 12); + + uint c18 = Nat192.AddToEachOther(zz, 6, zz, 12); + uint c12 = c18 + Nat192.AddTo(zz, 0, zz, 6, 0); + c18 += Nat192.AddTo(zz, 18, zz, 12, c12); + + uint[] dx = Nat192.Create(), dy = Nat192.Create(); + bool neg = Nat192.Diff(x, 6, x, 0, dx, 0) != Nat192.Diff(y, 6, y, 0, dy, 0); + + uint[] tt = Nat192.CreateExt(); + Nat192.Mul(dx, dy, tt); + + c18 += neg ? Nat.AddTo(12, tt, 0, zz, 6) : (uint)Nat.SubFrom(12, tt, 0, zz, 6); + Nat.AddWordExt(12, c18, zz, 18); + } + + public static void Square(uint[] x, uint[] zz) + { + Nat192.Square(x, zz); + Nat192.Square(x, 6, zz, 12); + + uint c18 = Nat192.AddToEachOther(zz, 6, zz, 12); + uint c12 = c18 + Nat192.AddTo(zz, 0, zz, 6, 0); + c18 += Nat192.AddTo(zz, 18, zz, 12, c12); + + uint[] dx = Nat192.Create(); + Nat192.Diff(x, 6, x, 0, dx, 0); + + uint[] m = Nat192.CreateExt(); + Nat192.Square(dx, m); + + c18 += (uint)Nat.SubFrom(12, m, 0, zz, 6); + Nat.AddWordExt(12, c18, zz, 18); + } + } +} diff --git a/crypto/src/math/ec/custom/sec/SecP384R1Curve.cs b/crypto/src/math/ec/custom/sec/SecP384R1Curve.cs new file mode 100644 index 000000000..9366232c6 --- /dev/null +++ b/crypto/src/math/ec/custom/sec/SecP384R1Curve.cs @@ -0,0 +1,95 @@ +using System; + +using Org.BouncyCastle.Math.Field; +using Org.BouncyCastle.Utilities.Encoders; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal class SecP384R1Curve + : ECCurve + { + public static readonly BigInteger q = new BigInteger(1, + Hex.Decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFF")); + + private const int SecP384R1_DEFAULT_COORDS = COORD_JACOBIAN; + + protected readonly SecP384R1Point m_infinity; + + public SecP384R1Curve() + : base(FiniteFields.GetPrimeField(q)) + { + this.m_infinity = new SecP384R1Point(this, null, null); + + this.m_a = FromBigInteger(new BigInteger(1, + Hex.Decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFC"))); + this.m_b = FromBigInteger(new BigInteger(1, + Hex.Decode("B3312FA7E23EE7E4988E056BE3F82D19181D9C6EFE8141120314088F5013875AC656398D8A2ED19D2A85C8EDD3EC2AEF"))); + this.m_order = new BigInteger(1, Hex.Decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFC7634D81F4372DDF581A0DB248B0A77AECEC196ACCC52973")); + this.m_cofactor = BigInteger.One; + this.m_coord = SecP384R1_DEFAULT_COORDS; + } + + protected override ECCurve CloneCurve() + { + return new SecP384R1Curve(); + } + + public override bool SupportsCoordinateSystem(int coord) + { + switch (coord) + { + case COORD_JACOBIAN: + return true; + default: + return false; + } + } + + public virtual BigInteger Q + { + get { return q; } + } + + public override ECPoint Infinity + { + get { return m_infinity; } + } + + public override int FieldSize + { + get { return q.BitLength; } + } + + public override ECFieldElement FromBigInteger(BigInteger x) + { + return new SecP384R1FieldElement(x); + } + + protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, bool withCompression) + { + return new SecP384R1Point(this, x, y, withCompression); + } + + protected override ECPoint DecompressPoint(int yTilde, BigInteger X1) + { + ECFieldElement x = FromBigInteger(X1); + ECFieldElement alpha = x.Square().Add(A).Multiply(x).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"); + + if (beta.TestBitZero() != (yTilde == 1)) + { + // Use the other root + beta = beta.Negate(); + } + + return new SecP384R1Point(this, x, beta, true); + } + } +} diff --git a/crypto/src/math/ec/custom/sec/SecP384R1Field.cs b/crypto/src/math/ec/custom/sec/SecP384R1Field.cs new file mode 100644 index 000000000..8f9094b5b --- /dev/null +++ b/crypto/src/math/ec/custom/sec/SecP384R1Field.cs @@ -0,0 +1,227 @@ +using System; +using System.Diagnostics; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal class SecP384R1Field + { + // 2^384 - 2^128 - 2^96 + 2^32 - 1 + internal static readonly uint[] P = new uint[]{ 0xFFFFFFFF, 0x00000000, 0x00000000, 0xFFFFFFFF, 0xFFFFFFFE, 0xFFFFFFFF, + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; + private const uint P11 = 0xFFFFFFFF; + private static readonly uint[] PExt = new uint[]{ 0x00000001, 0xFFFFFFFE, 0x00000000, 0x00000002, 0x00000000, 0xFFFFFFFE, + 0x00000000, 0x00000002, 0x00000001, 0x00000000, 0x00000000, 0x00000000, 0xFFFFFFFE, 0x00000001, 0x00000000, + 0xFFFFFFFE, 0xFFFFFFFD, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; + private const uint PExt23 = 0xFFFFFFFF; + + public static void Add(uint[] x, uint[] y, uint[] z) + { + uint c = Nat.Add(12, x, y, z); + if (c != 0 || (z[11] == P11 && Nat.Gte(12, z, P))) + { + Nat.Sub(12, z, P, z); + } + } + + public static void AddExt(uint[] xx, uint[] yy, uint[] zz) + { + uint c = Nat.Add(24, xx, yy, zz); + if (c != 0 || (zz[23] == PExt23 && Nat.Gte(24, zz, PExt))) + { + Nat.Sub(24, zz, PExt, zz); + } + } + + public static void AddOne(uint[] x, uint[] z) + { + Nat.Copy(12, x, z); + uint c = Nat.Inc(12, z, 0); + if (c != 0 || (z[11] == P11 && Nat.Gte(12, z, P))) + { + Nat.Sub(12, z, P, z); + } + } + + public static uint[] FromBigInteger(BigInteger x) + { + uint[] z = Nat.FromBigInteger(384, x); + if (z[11] == P11 && Nat.Gte(12, z, P)) + { + Nat.Sub(12, z, P, z); + } + return z; + } + + public static void Half(uint[] x, uint[] z) + { + if ((x[0] & 1) == 0) + { + Nat.ShiftDownBit(12, x, 0, z); + } + else + { + uint c = Nat.Add(12, x, P, z); + Nat.ShiftDownBit(12, z, c); + } + } + + public static void Multiply(uint[] x, uint[] y, uint[] z) + { + uint[] tt = Nat.Create(24); + Nat384.Mul(x, y, tt); + Reduce(tt, z); + } + + public static void Negate(uint[] x, uint[] z) + { + if (Nat.IsZero(12, x)) + { + Nat.Zero(12, z); + } + else + { + Nat.Sub(12, P, x, z); + } + } + + public static void Reduce(uint[] xx, uint[] z) + { + long xx12 = xx[12], xx13 = xx[13], xx14 = xx[14], xx15 = xx[15]; + long xx16 = xx[16], xx17 = xx[17], xx18 = xx[18], xx19 = xx[19]; + long xx20 = xx[20], xx21 = xx[21], xx22 = xx[22], xx23 = xx[23]; + + long cc = 0; + cc += (long)xx[0] + xx12 + xx20 + xx21 - xx23; + z[0] = (uint)cc; + cc >>= 32; + cc += (long)xx[1] + xx13 + xx22 + xx23 - xx12 - xx20; + z[1] = (uint)cc; + cc >>= 32; + cc += (long)xx[2] + xx14 + xx23 - xx13 - xx21; + z[2] = (uint)cc; + cc >>= 32; + cc += (long)xx[3] + xx12 + xx15 + xx20 + xx21 - xx14 - xx22 - xx23; + z[3] = (uint)cc; + cc >>= 32; + cc += (long)xx[4] + xx12 + xx13 + xx16 + xx20 + ((xx21 - xx23) << 1) + xx22 - xx15; + z[4] = (uint)cc; + cc >>= 32; + cc += (long)xx[5] + xx13 + xx14 + xx17 + xx21 + (xx22 << 1) + xx23 - xx16; + z[5] = (uint)cc; + cc >>= 32; + cc += (long)xx[6] + xx14 + xx15 + xx18 + xx22 + (xx23 << 1) - xx17; + z[6] = (uint)cc; + cc >>= 32; + cc += (long)xx[7] + xx15 + xx16 + xx19 + xx23 - xx18; + z[7] = (uint)cc; + cc >>= 32; + cc += (long)xx[8] + xx16 + xx17 + xx20 - xx19; + z[8] = (uint)cc; + cc >>= 32; + cc += (long)xx[9] + xx17 + xx18 + xx21 - xx20; + z[9] = (uint)cc; + cc >>= 32; + cc += (long)xx[10] + xx18 + xx19 + xx22 - xx21; + z[10] = (uint)cc; + cc >>= 32; + cc += (long)xx[11] + xx19 + xx20 + xx23 - xx22; + z[11] = (uint)cc; + cc >>= 32; + + int c = (int)cc; + if (c > 0) + { + Reduce32((uint)c, z); + } + else + { + while (c < 0) + { + c += (int)Nat256.Add(z, P, z); + } + } + } + + public static void Reduce32(uint x, uint[] z) + { + long xx12 = x; + + long cc = 0; + cc += (long)z[0] + xx12; + z[0] = (uint)cc; + cc >>= 32; + cc += (long)z[1] - xx12; + z[1] = (uint)cc; + cc >>= 32; + cc += (long)z[2]; + z[2] = (uint)cc; + cc >>= 32; + cc += (long)z[3] + xx12; + z[3] = (uint)cc; + cc >>= 32; + cc += (long)z[4] + xx12; + z[4] = (uint)cc; + cc >>= 32; + + Debug.Assert(cc >= 0); + + if (cc > 0) + { + uint c = Nat.AddWord(12, (uint)cc, z, 5); + if (c != 0 || (z[11] == P11 && Nat.Gte(12, z, P))) + { + Nat.Sub(12, z, P, z); + } + } + } + + public static void Square(uint[] x, uint[] z) + { + uint[] tt = Nat.Create(24); + Nat384.Square(x, tt); + Reduce(tt, z); + } + + public static void SquareN(uint[] x, int n, uint[] z) + { + Debug.Assert(n > 0); + + uint[] tt = Nat.Create(24); + Nat384.Square(x, tt); + Reduce(tt, z); + + while (--n > 0) + { + Nat384.Square(z, tt); + Reduce(tt, z); + } + } + + public static void Subtract(uint[] x, uint[] y, uint[] z) + { + int c = Nat.Sub(12, x, y, z); + if (c != 0) + { + Nat.Add(12, z, P, z); + } + } + + public static void SubtractExt(uint[] xx, uint[] yy, uint[] zz) + { + int c = Nat.Sub(24, xx, yy, zz); + if (c != 0) + { + Nat.Add(24, zz, PExt, zz); + } + } + + public static void Twice(uint[] x, uint[] z) + { + uint c = Nat.ShiftUpBit(12, x, 0, z); + if (c != 0 || (z[11] == P11 && Nat.Gte(12, z, P))) + { + Nat.Sub(12, z, P, z); + } + } + } +} diff --git a/crypto/src/math/ec/custom/sec/SecP384R1FieldElement.cs b/crypto/src/math/ec/custom/sec/SecP384R1FieldElement.cs new file mode 100644 index 000000000..bca260de9 --- /dev/null +++ b/crypto/src/math/ec/custom/sec/SecP384R1FieldElement.cs @@ -0,0 +1,155 @@ +using System; + +using Org.BouncyCastle.Utilities; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal class SecP384R1FieldElement + : ECFieldElement + { + public static readonly BigInteger Q = SecP384R1Curve.q; + + protected internal readonly uint[] x; + + public SecP384R1FieldElement(BigInteger x) + { + if (x == null || x.SignValue < 0 || x.CompareTo(Q) >= 0) + throw new ArgumentException("value invalid for SecP384R1FieldElement", "x"); + + this.x = SecP384R1Field.FromBigInteger(x); + } + + public SecP384R1FieldElement() + { + this.x = Nat.Create(12); + } + + protected internal SecP384R1FieldElement(uint[] x) + { + this.x = x; + } + + public override bool IsZero + { + get { return Nat.IsZero(12, x); } + } + + public override bool IsOne + { + get { return Nat.IsOne(12, x); } + } + + public override bool TestBitZero() + { + return Nat.GetBit(x, 0) == 1; + } + + public override BigInteger ToBigInteger() + { + return Nat.ToBigInteger(12, x); + } + + public override string FieldName + { + get { return "SecP384R1Field"; } + } + + public override int FieldSize + { + get { return Q.BitLength; } + } + + public override ECFieldElement Add(ECFieldElement b) + { + uint[] z = Nat.Create(12); + SecP384R1Field.Add(x, ((SecP384R1FieldElement)b).x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement AddOne() + { + uint[] z = Nat.Create(12); + SecP384R1Field.AddOne(x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Subtract(ECFieldElement b) + { + uint[] z = Nat.Create(12); + SecP384R1Field.Subtract(x, ((SecP384R1FieldElement)b).x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Multiply(ECFieldElement b) + { + uint[] z = Nat.Create(12); + SecP384R1Field.Multiply(x, ((SecP384R1FieldElement)b).x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Divide(ECFieldElement b) + { + //return Multiply(b.Invert()); + uint[] z = Nat.Create(12); + Mod.Invert(SecP384R1Field.P, ((SecP384R1FieldElement)b).x, z); + SecP384R1Field.Multiply(z, x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Negate() + { + uint[] z = Nat.Create(12); + SecP384R1Field.Negate(x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Square() + { + uint[] z = Nat.Create(12); + SecP384R1Field.Square(x, z); + return new SecP384R1FieldElement(z); + } + + public override ECFieldElement Invert() + { + //return new SecP384R1FieldElement(ToBigInteger().ModInverse(Q)); + uint[] z = Nat.Create(12); + Mod.Invert(SecP384R1Field.P, x, z); + return new SecP384R1FieldElement(z); + } + + /** + * return a sqrt root - the routine verifies that the calculation returns the right value - if + * none exists it returns null. + */ + public override ECFieldElement Sqrt() + { + ECFieldElement root = new FpFieldElement(Q, ToBigInteger()).Sqrt(); + return root == null ? null : new SecP384R1FieldElement(root.ToBigInteger()); + } + + public override bool Equals(object obj) + { + return Equals(obj as SecP384R1FieldElement); + } + + public override bool Equals(ECFieldElement other) + { + return Equals(other as SecP384R1FieldElement); + } + + public virtual bool Equals(SecP384R1FieldElement other) + { + if (this == other) + return true; + if (null == other) + return false; + return Arrays.AreEqual(x, other.x); + } + + public override int GetHashCode() + { + return Q.GetHashCode() ^ Arrays.GetHashCode(x); + } + } +} diff --git a/crypto/src/math/ec/custom/sec/SecP384R1Point.cs b/crypto/src/math/ec/custom/sec/SecP384R1Point.cs new file mode 100644 index 000000000..6547df20c --- /dev/null +++ b/crypto/src/math/ec/custom/sec/SecP384R1Point.cs @@ -0,0 +1,287 @@ +using System; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal class SecP384R1Point + : ECPointBase + { + /** + * Create a point which encodes with point compression. + * + * @param curve + * the curve to use + * @param x + * affine x co-ordinate + * @param y + * affine y co-ordinate + * + * @deprecated Use ECCurve.createPoint to construct points + */ + public SecP384R1Point(ECCurve curve, ECFieldElement x, ECFieldElement y) + : this(curve, x, y, false) + { + } + + /** + * Create a point that encodes with or without point compresion. + * + * @param curve + * the curve to use + * @param x + * affine x co-ordinate + * @param y + * affine y co-ordinate + * @param withCompression + * if true encode with point compression + * + * @deprecated per-point compression property will be removed, refer + * {@link #getEncoded(bool)} + */ + public SecP384R1Point(ECCurve curve, ECFieldElement x, ECFieldElement y, bool withCompression) + : base(curve, x, y, withCompression) + { + if ((x == null) != (y == null)) + throw new ArgumentException("Exactly one of the field elements is null"); + } + + internal SecP384R1Point(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression) + : base(curve, x, y, zs, withCompression) + { + } + + protected override ECPoint Detach() + { + return new SecP384R1Point(null, AffineXCoord, AffineYCoord); + } + + protected internal override bool CompressionYTilde + { + get { return this.AffineYCoord.TestBitZero(); } + } + + 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; + + SecP384R1FieldElement X1 = (SecP384R1FieldElement)this.RawXCoord, Y1 = (SecP384R1FieldElement)this.RawYCoord; + SecP384R1FieldElement X2 = (SecP384R1FieldElement)b.RawXCoord, Y2 = (SecP384R1FieldElement)b.RawYCoord; + + SecP384R1FieldElement Z1 = (SecP384R1FieldElement)this.RawZCoords[0]; + SecP384R1FieldElement Z2 = (SecP384R1FieldElement)b.RawZCoords[0]; + + uint[] tt1 = Nat.Create(24); + uint[] tt2 = Nat.Create(24); + uint[] t3 = Nat.Create(12); + uint[] t4 = Nat.Create(12); + + bool Z1IsOne = Z1.IsOne; + uint[] U2, S2; + if (Z1IsOne) + { + U2 = X2.x; + S2 = Y2.x; + } + else + { + S2 = t3; + SecP384R1Field.Square(Z1.x, S2); + + U2 = tt2; + SecP384R1Field.Multiply(S2, X2.x, U2); + + SecP384R1Field.Multiply(S2, Z1.x, S2); + SecP384R1Field.Multiply(S2, Y2.x, S2); + } + + bool Z2IsOne = Z2.IsOne; + uint[] U1, S1; + if (Z2IsOne) + { + U1 = X1.x; + S1 = Y1.x; + } + else + { + S1 = t4; + SecP384R1Field.Square(Z2.x, S1); + + U1 = tt1; + SecP384R1Field.Multiply(S1, X1.x, U1); + + SecP384R1Field.Multiply(S1, Z2.x, S1); + SecP384R1Field.Multiply(S1, Y1.x, S1); + } + + uint[] H = Nat.Create(12); + SecP384R1Field.Subtract(U1, U2, H); + + uint[] R = Nat.Create(12);// tt2; + SecP384R1Field.Subtract(S1, S2, R); + + // Check if b == this or b == -this + if (Nat.IsZero(12, H)) + { + if (Nat.IsZero(12, 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; + SecP384R1Field.Square(H, HSquared); + + uint[] G = Nat.Create(12); + SecP384R1Field.Multiply(HSquared, H, G); + + uint[] V = t3; + SecP384R1Field.Multiply(HSquared, U1, V); + + Nat384.Mul(S1, G, tt1); + + SecP384R1FieldElement X3 = new SecP384R1FieldElement(t4); + SecP384R1Field.Square(R, X3.x); + SecP384R1Field.Add(X3.x, G, X3.x); + SecP384R1Field.Subtract(X3.x, V, X3.x); + SecP384R1Field.Subtract(X3.x, V, X3.x); + + SecP384R1FieldElement Y3 = new SecP384R1FieldElement(G); + SecP384R1Field.Subtract(V, X3.x, Y3.x); + Nat384.Mul(Y3.x, R, tt2); + SecP384R1Field.SubtractExt(tt2, tt1, tt2); + SecP384R1Field.Reduce(tt2, Y3.x); + + SecP384R1FieldElement Z3 = new SecP384R1FieldElement(H); + if (!Z1IsOne) + { + SecP384R1Field.Multiply(Z3.x, Z1.x, Z3.x); + } + if (!Z2IsOne) + { + SecP384R1Field.Multiply(Z3.x, Z2.x, Z3.x); + } + + ECFieldElement[] zs = new ECFieldElement[] { Z3 }; + + return new SecP384R1Point(curve, X3, Y3, zs, IsCompressed); + } + + public override ECPoint Twice() + { + if (this.IsInfinity) + return this; + + ECCurve curve = this.Curve; + + SecP384R1FieldElement Y1 = (SecP384R1FieldElement)this.RawYCoord; + if (Y1.IsZero) + return curve.Infinity; + + SecP384R1FieldElement X1 = (SecP384R1FieldElement)this.RawXCoord, Z1 = (SecP384R1FieldElement)this.RawZCoords[0]; + + uint[] t1 = Nat.Create(12); + uint[] t2 = Nat.Create(12); + + uint[] Y1Squared = Nat.Create(12); + SecP384R1Field.Square(Y1.x, Y1Squared); + + uint[] T = Nat.Create(12); + SecP384R1Field.Square(Y1Squared, T); + + bool Z1IsOne = Z1.IsOne; + + uint[] Z1Squared = Z1.x; + if (!Z1IsOne) + { + Z1Squared = t2; + SecP384R1Field.Square(Z1.x, Z1Squared); + } + + SecP384R1Field.Subtract(X1.x, Z1Squared, t1); + + uint[] M = t2; + SecP384R1Field.Add(X1.x, Z1Squared, M); + SecP384R1Field.Multiply(M, t1, M); + SecP384R1Field.Twice(M, t1); + SecP384R1Field.Add(M, t1, M); + + uint[] S = Y1Squared; + SecP384R1Field.Multiply(Y1Squared, X1.x, S); + uint c = Nat.ShiftUpBits(12, S, 2, 0); + SecP384R1Field.Reduce32(c, S); + + c = Nat.ShiftUpBits(12, T, 3, 0, t1); + SecP384R1Field.Reduce32(c, t1); + + SecP384R1FieldElement X3 = new SecP384R1FieldElement(T); + SecP384R1Field.Square(M, X3.x); + SecP384R1Field.Subtract(X3.x, S, X3.x); + SecP384R1Field.Subtract(X3.x, S, X3.x); + + SecP384R1FieldElement Y3 = new SecP384R1FieldElement(S); + SecP384R1Field.Subtract(S, X3.x, Y3.x); + SecP384R1Field.Multiply(Y3.x, M, Y3.x); + SecP384R1Field.Subtract(Y3.x, t1, Y3.x); + + SecP384R1FieldElement Z3 = new SecP384R1FieldElement(M); + SecP384R1Field.Twice(Y1.x, Z3.x); + if (!Z1IsOne) + { + SecP384R1Field.Multiply(Z3.x, Z1.x, Z3.x); + } + + return new SecP384R1Point(curve, X3, Y3, new ECFieldElement[] { Z3 }, IsCompressed); + } + + public override ECPoint TwicePlus(ECPoint b) + { + if (this == b) + return ThreeTimes(); + if (this.IsInfinity) + return b; + if (b.IsInfinity) + return Twice(); + + ECFieldElement Y1 = this.RawYCoord; + if (Y1.IsZero) + return b; + + return Twice().Add(b); + } + + public override ECPoint ThreeTimes() + { + if (this.IsInfinity || this.RawYCoord.IsZero) + return this; + + // NOTE: Be careful about recursions between TwicePlus and ThreeTimes + return Twice().Add(this); + } + + public override ECPoint Subtract(ECPoint b) + { + if (b.IsInfinity) + return this; + + return Add(b.Negate()); + } + + public override ECPoint Negate() + { + if (IsInfinity) + return this; + + return new SecP384R1Point(Curve, RawXCoord, RawYCoord.Negate(), RawZCoords, IsCompressed); + } + } +} |