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author | Peter Dettman <peter.dettman@bouncycastle.org> | 2014-03-17 15:45:27 +0700 |
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committer | Peter Dettman <peter.dettman@bouncycastle.org> | 2014-03-17 15:45:27 +0700 |
commit | c368e7ca8460a11d02d2a85588bac51ec71b0424 (patch) | |
tree | 5ab2b0ae196cc36404170807bbc8ec52ed4b315a /crypto/src/math/ec/custom/sec/Curve25519Field.cs | |
parent | Take advantage of GLV (when available) in sum-of-multiplies methods (diff) | |
download | BouncyCastle.NET-ed25519-c368e7ca8460a11d02d2a85588bac51ec71b0424.tar.xz |
Port of latest Curve25519 stuff from Java build
Diffstat (limited to 'crypto/src/math/ec/custom/sec/Curve25519Field.cs')
-rw-r--r-- | crypto/src/math/ec/custom/sec/Curve25519Field.cs | 210 |
1 files changed, 0 insertions, 210 deletions
diff --git a/crypto/src/math/ec/custom/sec/Curve25519Field.cs b/crypto/src/math/ec/custom/sec/Curve25519Field.cs deleted file mode 100644 index ee0f88311..000000000 --- a/crypto/src/math/ec/custom/sec/Curve25519Field.cs +++ /dev/null @@ -1,210 +0,0 @@ -using System; -using System.Diagnostics; - -namespace Org.BouncyCastle.Math.EC.Custom.Sec -{ - internal class Curve25519Field - { - // 2^255 - 2^4 - 2^1 - 1 - internal static readonly uint[] P = new uint[]{ 0xFFFFFFED, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, - 0xFFFFFFFF, 0x7FFFFFFF }; - private const int P7 = 0x7FFFFFFF; - private static readonly uint[] PExt = new uint[]{ 0x00000169, 0x00000000, 0x00000000, 0x00000000, 0x00000000, - 0x00000000, 0x00000000, 0x00000000, 0xFFFFFFED, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, - 0xFFFFFFFF, 0x3FFFFFFF }; - private const uint PInv = 0x13; - - public static void Add(uint[] x, uint[] y, uint[] z) - { - Nat256.Add(x, y, z); - if (Nat256.Gte(z, P)) - { - AddPInvTo(z); - } - } - - public static void AddExt(uint[] xx, uint[] yy, uint[] zz) - { - Nat.Add(16, xx, yy, zz); - if (Nat.Gte(16, zz, PExt)) - { - SubPExtFrom(zz); - } - } - - public static void AddOne(uint[] x, uint[] z) - { - Nat.Inc(8, x, z); - if (Nat256.Gte(z, P)) - { - AddPInvTo(z); - } - } - - public static uint[] FromBigInteger(BigInteger x) - { - uint[] z = Nat256.FromBigInteger(x); - while (Nat256.Gte(z, P)) - { - Nat256.SubFrom(P, z); - } - return z; - } - - public static void Half(uint[] x, uint[] z) - { - if ((x[0] & 1) == 0) - { - Nat.ShiftDownBit(8, x, 0, z); - } - else - { - Nat256.Add(x, P, z); - Nat.ShiftDownBit(8, z, 0); - } - } - - public static void Multiply(uint[] x, uint[] y, uint[] z) - { - uint[] tt = Nat256.CreateExt(); - Nat256.Mul(x, y, tt); - Reduce(tt, z); - } - - public static void Negate(uint[] x, uint[] z) - { - if (Nat256.IsZero(x)) - { - Nat256.Zero(z); - } - else - { - Nat256.Sub(P, x, z); - } - } - - public static void Reduce(uint[] xx, uint[] z) - { - Debug.Assert(xx[15] >> 30 == 0); - - uint xx07 = xx[7]; - Nat.ShiftUpBit(8, xx, 8, xx07, z, 0); - uint c = Nat256.MulByWordAddTo(PInv, xx, z) << 1; - uint z07 = z[7]; - z[7] = z07 & P7; - c += (z07 >> 31) - (xx07 >> 31); - Nat.AddWordTo(8, c * PInv, z); - if (Nat256.Gte(z, P)) - { - AddPInvTo(z); - } - } - - public static void Square(uint[] x, uint[] z) - { - uint[] tt = Nat256.CreateExt(); - Nat256.Square(x, tt); - Reduce(tt, z); - } - - public static void SquareN(uint[] x, int n, uint[] z) - { - // assert n > 0; - - uint[] tt = Nat256.CreateExt(); - Nat256.Square(x, tt); - Reduce(tt, z); - - while (--n > 0) - { - Nat256.Square(z, tt); - Reduce(tt, z); - } - } - - public static void Subtract(uint[] x, uint[] y, uint[] z) - { - int c = Nat256.Sub(x, y, z); - if (c != 0) - { - SubPInvFrom(z); - } - } - - public static void SubtractExt(uint[] xx, uint[] yy, uint[] zz) - { - int c = Nat.Sub(16, xx, yy, zz); - if (c != 0) - { - AddPExtTo(zz); - } - } - - public static void Twice(uint[] x, uint[] z) - { - Nat.ShiftUpBit(8, x, 0, z); - if (Nat256.Gte(z, P)) - { - AddPInvTo(z); - } - } - - private static void AddPExtTo(uint[] zz) - { - ulong c = (ulong)zz[0] + PExt[0]; - zz[0] = (uint)c; - c >>= 32; - - int i = 1 - (int)c; - i = (i << 3) - i; - - while (++i < 16) - { - c += (ulong)zz[i] + PExt[i]; - zz[i] = (uint)c; - c >>= 32; - } - } - - private static void SubPExtFrom(uint[] zz) - { - long c = (long)zz[0] - PExt[0]; - zz[0] = (uint)c; - c >>= 32; - - int i = 1 + (int)c; - i = (i << 3) - i; - - while (++i < 16) - { - c += (long)zz[i] - PExt[i]; - zz[i] = (uint)c; - c >>= 32; - } - } - - private static void AddPInvTo(uint[] z) - { - ulong c = (ulong)z[0] + PInv; - z[0] = (uint)c; - c >>= 32; - if (c != 0) - { - Nat.IncAt(7, z, 1); - } - z[7] &= P7; - } - - private static void SubPInvFrom(uint[] z) - { - long c = (long)z[0] - PInv; - z[0] = (uint)c; - c >>= 32; - if (c != 0) - { - Nat.DecAt(7, z, 1); - } - z[7] &= P7; - } - } -} |