diff options
Diffstat (limited to 'crypto/src/math/ec/Nat.cs')
| -rw-r--r-- | crypto/src/math/ec/Nat.cs | 97 |
1 files changed, 65 insertions, 32 deletions
diff --git a/crypto/src/math/ec/Nat.cs b/crypto/src/math/ec/Nat.cs index 819979473..821d5065d 100644 --- a/crypto/src/math/ec/Nat.cs +++ b/crypto/src/math/ec/Nat.cs @@ -2,7 +2,6 @@ using System.Diagnostics; using Org.BouncyCastle.Crypto.Utilities; -using Org.BouncyCastle.Math; namespace Org.BouncyCastle.Math.EC { @@ -32,6 +31,18 @@ namespace Org.BouncyCastle.Math.EC return (uint)c; } + public static uint AddBothTo(int len, uint[] x, int xOff, uint[] y, int yOff, uint[] z, int zOff) + { + ulong c = 0; + for (int i = 0; i < len; ++i) + { + c += (ulong)x[xOff + i] + y[yOff + i] + z[zOff + i]; + z[zOff + i] = (uint)c; + c >>= 32; + } + return (uint)c; + } + // TODO Re-write to allow full range for x? public static uint AddDWord(int len, ulong x, uint[] z, int zOff) { @@ -46,14 +57,13 @@ namespace Org.BouncyCastle.Math.EC return c == 0 ? 0 : Inc(len, z, zOff + 2); } - public static uint AddToExt(int len, uint[] x, int xOff, uint[] zz, int zzOff) + public static uint AddTo(int len, uint[] x, int xOff, uint[] z, int zOff) { - Debug.Assert(zzOff <= len); ulong c = 0; for (int i = 0; i < len; ++i) { - c += (ulong)x[xOff + i] + zz[zzOff + i]; - zz[zzOff + i] = (uint)c; + c += (ulong)x[xOff + i] + z[zOff + i]; + z[zOff + i] = (uint)c; c >>= 32; } return (uint)c; @@ -205,23 +215,50 @@ namespace Org.BouncyCastle.Math.EC public static void Mul(int len, uint[] x, uint[] y, uint[] zz) { - zz[len] = (uint)MulWordExt(len, x[0], y, zz, 0); + zz[len] = (uint)MulWord(len, x[0], y, zz, 0); for (int i = 1; i < len; ++i) { - zz[i + len] = (uint)MulWordAddExt(len, x[i], y, zz, i); + zz[i + len] = (uint)MulWordAdd(len, x[i], y, zz, i); + } + } + + public static uint Mul31BothAdd(int len, uint a, uint[] x, uint b, uint[] y, uint[] z, int zOff) + { + ulong c = 0, aVal = (ulong)a, bVal = (ulong)b; + int i = 0; + do + { + c += aVal * x[i] + bVal * y[i] + z[zOff + i]; + z[zOff + i] = (uint)c; + c >>= 32; + } + while (++i < len); + return (uint)c; + } + + public static uint MulWord(int len, uint x, uint[] y, uint[] z, int zOff) + { + ulong c = 0, xVal = (ulong)x; + int i = 0; + do + { + c += xVal * y[i]; + z[zOff + i] = (uint)c; + c >>= 32; } + while (++i < len); + return (uint)c; } - public static uint MulWordAddExt(int len, uint x, uint[] y, uint[] zz, int zzOff) + public static uint MulWordAdd(int len, uint x, uint[] y, uint[] z, int zOff) { - Debug.Assert(zzOff <= len); ulong c = 0, xVal = (ulong)x; int i = 0; do { - c += xVal * y[i] + zz[zzOff + i]; - zz[zzOff + i] = (uint)c; + c += xVal * y[i] + z[zOff + i]; + z[zOff + i] = (uint)c; c >>= 32; } while (++i < len); @@ -244,21 +281,6 @@ namespace Org.BouncyCastle.Math.EC return c == 0 ? 0 : Inc(len, z, zOff + 3); } - public static uint MulWordExt(int len, uint x, uint[] y, uint[] zz, int zzOff) - { - Debug.Assert(zzOff <= len); - ulong c = 0, xVal = (ulong)x; - int i = 0; - do - { - c += xVal * y[i]; - zz[zzOff + i] = (uint)c; - c >>= 32; - } - while (++i < len); - return (uint)c; - } - public static uint ShiftDownBit(int len, uint[] z, uint c) { int i = len; @@ -296,13 +318,13 @@ namespace Org.BouncyCastle.Math.EC return c << -bits; } - public static uint ShiftDownBitsExt(int len, uint[] xx, int xxOff, int bits, uint c, uint[] z) + public static uint ShiftDownBits(int len, uint[] x, int xOff, int bits, uint c, uint[] z) { Debug.Assert(bits > 0 && bits < 32); int i = len; while (--i >= 0) { - uint next = xx[xxOff + i]; + uint next = x[xOff + i]; z[i] = (next >> bits) | (c << -bits); c = next; } @@ -430,6 +452,18 @@ namespace Org.BouncyCastle.Math.EC return (int)c; } + public static int SubBothFrom(int len, uint[] x, int xOff, uint[] y, int yOff, uint[] z, int zOff) + { + long c = 0; + for (int i = 0; i < len; ++i) + { + c += (long)z[zOff + i] - x[xOff + i] - y[yOff + i]; + z[zOff + i] = (uint)c; + c >>= 32; + } + return (int)c; + } + // TODO Re-write to allow full range for x? public static int SubDWord(int len, ulong x, uint[] z) { @@ -444,14 +478,13 @@ namespace Org.BouncyCastle.Math.EC return c == 0 ? 0 : Dec(len, z, 2); } - public static int SubFromExt(int len, uint[] x, int xOff, uint[] zz, int zzOff) + public static int SubFrom(int len, uint[] x, int xOff, uint[] z, int zOff) { - Debug.Assert(zzOff <= len); long c = 0; for (int i = 0; i < len; ++i) { - c += (long)zz[zzOff + i] - x[xOff + i]; - zz[zzOff + i] = (uint)c; + c += (long)z[zOff + i] - x[xOff + i]; + z[zOff + i] = (uint)c; c >>= 32; } return (int)c; |