diff options
Diffstat (limited to 'crypto/src/math/ec/custom/sec/SecP384R1Field.cs')
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP384R1Field.cs | 227 |
1 files changed, 227 insertions, 0 deletions
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); + } + } + } +} |