From e7c2c2029676b6dd0f13560b56aa9611c51c99f7 Mon Sep 17 00:00:00 2001 From: Peter Dettman Date: Fri, 31 Jan 2014 19:05:46 +0700 Subject: Avoid modifying the input to the Reduce() methods --- crypto/src/math/ec/custom/sec/Nat192.cs | 33 ++++++++++---------- crypto/src/math/ec/custom/sec/Nat256.cs | 41 +++++++++++++------------ crypto/src/math/ec/custom/sec/SecP192K1Field.cs | 12 +++----- crypto/src/math/ec/custom/sec/SecP256K1Field.cs | 12 +++----- 4 files changed, 48 insertions(+), 50 deletions(-) (limited to 'crypto') diff --git a/crypto/src/math/ec/custom/sec/Nat192.cs b/crypto/src/math/ec/custom/sec/Nat192.cs index b61c7a468..29f6f28e6 100644 --- a/crypto/src/math/ec/custom/sec/Nat192.cs +++ b/crypto/src/math/ec/custom/sec/Nat192.cs @@ -321,37 +321,38 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec } } - public static ulong Mul33AddExt(uint x, uint[] yy, int yyOff, uint[] zz, int zzOff) + public static ulong Mul33AddExt(uint w, uint[] xx, int xxOff, uint[] yy, int yyOff, uint[] zz, int zzOff) { - Debug.Assert(x >> 31 == 0); + Debug.Assert(w >> 31 == 0); + Debug.Assert(xxOff <= 6); Debug.Assert(yyOff <= 6); Debug.Assert(zzOff <= 6); - ulong c = 0, xVal = x; - ulong yy00 = yy[yyOff + 0]; - c += xVal * yy00 + zz[zzOff + 0]; + ulong c = 0, wVal = w; + ulong xx00 = xx[xxOff + 0]; + c += wVal * xx00 + yy[yyOff + 0]; zz[zzOff + 0] = (uint)c; c >>= 32; - ulong yy01 = yy[yyOff + 1]; - c += xVal * yy01 + yy00 + zz[zzOff + 1]; + ulong xx01 = xx[xxOff + 1]; + c += wVal * xx01 + xx00 + yy[yyOff + 1]; zz[zzOff + 1] = (uint)c; c >>= 32; - ulong yy02 = yy[yyOff + 2]; - c += xVal * yy02 + yy01 + zz[zzOff + 2]; + ulong xx02 = xx[xxOff + 2]; + c += wVal * xx02 + xx01 + yy[yyOff + 2]; zz[zzOff + 2] = (uint)c; c >>= 32; - ulong yy03 = yy[yyOff + 3]; - c += xVal * yy03 + yy02 + zz[zzOff + 3]; + ulong xx03 = xx[xxOff + 3]; + c += wVal * xx03 + xx02 + yy[yyOff + 3]; zz[zzOff + 3] = (uint)c; c >>= 32; - ulong yy04 = yy[yyOff + 4]; - c += xVal * yy04 + yy03 + zz[zzOff + 4]; + ulong xx04 = xx[xxOff + 4]; + c += wVal * xx04 + xx03 + yy[yyOff + 4]; zz[zzOff + 4] = (uint)c; c >>= 32; - ulong yy05 = yy[yyOff + 5]; - c += xVal * yy05 + yy04 + zz[zzOff + 5]; + ulong xx05 = xx[xxOff + 5]; + c += wVal * xx05 + xx04 + yy[yyOff + 5]; zz[zzOff + 5] = (uint)c; c >>= 32; - c += yy05; + c += xx05; return c; } diff --git a/crypto/src/math/ec/custom/sec/Nat256.cs b/crypto/src/math/ec/custom/sec/Nat256.cs index c71bc8322..5837a8820 100644 --- a/crypto/src/math/ec/custom/sec/Nat256.cs +++ b/crypto/src/math/ec/custom/sec/Nat256.cs @@ -353,45 +353,46 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec } } - public static ulong Mul33AddExt(uint x, uint[] yy, int yyOff, uint[] zz, int zzOff) + public static ulong Mul33AddExt(uint w, uint[] xx, int xxOff, uint[] yy, int yyOff, uint[] zz, int zzOff) { - Debug.Assert(x >> 31 == 0); + Debug.Assert(w >> 31 == 0); + Debug.Assert(xxOff <= 8); Debug.Assert(yyOff <= 8); Debug.Assert(zzOff <= 8); - ulong c = 0, xVal = x; - ulong yy00 = yy[yyOff + 0]; - c += xVal * yy00 + zz[zzOff + 0]; + ulong c = 0, wVal = w; + ulong xx00 = xx[xxOff + 0]; + c += wVal * xx00 + yy[yyOff + 0]; zz[zzOff + 0] = (uint)c; c >>= 32; - ulong yy01 = yy[yyOff + 1]; - c += xVal * yy01 + yy00 + zz[zzOff + 1]; + ulong xx01 = xx[xxOff + 1]; + c += wVal * xx01 + xx00 + yy[yyOff + 1]; zz[zzOff + 1] = (uint)c; c >>= 32; - ulong yy02 = yy[yyOff + 2]; - c += xVal * yy02 + yy01 + zz[zzOff + 2]; + ulong xx02 = xx[xxOff + 2]; + c += wVal * xx02 + xx01 + yy[yyOff + 2]; zz[zzOff + 2] = (uint)c; c >>= 32; - ulong yy03 = yy[yyOff + 3]; - c += xVal * yy03 + yy02 + zz[zzOff + 3]; + ulong xx03 = xx[xxOff + 3]; + c += wVal * xx03 + xx02 + yy[yyOff + 3]; zz[zzOff + 3] = (uint)c; c >>= 32; - ulong yy04 = yy[yyOff + 4]; - c += xVal * yy04 + yy03 + zz[zzOff + 4]; + ulong xx04 = xx[xxOff + 4]; + c += wVal * xx04 + xx03 + yy[yyOff + 4]; zz[zzOff + 4] = (uint)c; c >>= 32; - ulong yy05 = yy[yyOff + 5]; - c += xVal * yy05 + yy04 + zz[zzOff + 5]; + ulong xx05 = xx[xxOff + 5]; + c += wVal * xx05 + xx04 + yy[yyOff + 5]; zz[zzOff + 5] = (uint)c; c >>= 32; - ulong yy06 = yy[yyOff + 6]; - c += xVal * yy06 + yy05 + zz[zzOff + 6]; + ulong xx06 = xx[xxOff + 6]; + c += wVal * xx06 + xx05 + yy[yyOff + 6]; zz[zzOff + 6] = (uint)c; c >>= 32; - ulong yy07 = yy[yyOff + 7]; - c += xVal * yy07 + yy06 + zz[zzOff + 7]; + ulong xx07 = xx[xxOff + 7]; + c += wVal * xx07 + xx06 + yy[yyOff + 7]; zz[zzOff + 7] = (uint)c; c >>= 32; - c += yy07; + c += xx07; return c; } diff --git a/crypto/src/math/ec/custom/sec/SecP192K1Field.cs b/crypto/src/math/ec/custom/sec/SecP192K1Field.cs index 9da3c0257..11bc11d8d 100644 --- a/crypto/src/math/ec/custom/sec/SecP192K1Field.cs +++ b/crypto/src/math/ec/custom/sec/SecP192K1Field.cs @@ -84,19 +84,17 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec } } - public static void Reduce(uint[] tt, uint[] z) + public static void Reduce(uint[] xx, uint[] z) { - ulong c = Nat192.Mul33AddExt(PInv33, tt, 6, tt, 0); - c = Nat192.Mul33DWordAdd(PInv33, c, tt, 0); + ulong c = Nat192.Mul33AddExt(PInv33, xx, 6, xx, 0, z, 0); + c = Nat192.Mul33DWordAdd(PInv33, c, z, 0); Debug.Assert(c == 0 || c == 1); - if (c != 0 || (tt[5] == P5 && Nat192.Gte(tt, P))) + if (c != 0 || (z[5] == P5 && Nat192.Gte(z, P))) { - Nat192.AddDWord(PInv, tt, 0); + Nat192.AddDWord(PInv, z, 0); } - - Array.Copy(tt, 0, z, 0, 6); } public static void Square(uint[] x, uint[] z) diff --git a/crypto/src/math/ec/custom/sec/SecP256K1Field.cs b/crypto/src/math/ec/custom/sec/SecP256K1Field.cs index e7a73359f..3f5437d4d 100644 --- a/crypto/src/math/ec/custom/sec/SecP256K1Field.cs +++ b/crypto/src/math/ec/custom/sec/SecP256K1Field.cs @@ -86,19 +86,17 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec } } - public static void Reduce(uint[] tt, uint[] z) + public static void Reduce(uint[] xx, uint[] z) { - ulong c = Nat256.Mul33AddExt(PInv33, tt, 8, tt, 0); - c = Nat256.Mul33DWordAdd(PInv33, c, tt, 0); + ulong c = Nat256.Mul33AddExt(PInv33, xx, 8, xx, 0, z, 0); + c = Nat256.Mul33DWordAdd(PInv33, c, z, 0); Debug.Assert(c == 0 || c == 1); - if (c != 0 || (tt[7] == P7 && Nat256.Gte(tt, P))) + if (c != 0 || (z[7] == P7 && Nat256.Gte(z, P))) { - Nat256.AddDWord(PInv, tt, 0); + Nat256.AddDWord(PInv, z, 0); } - - Array.Copy(tt, 0, z, 0, 8); } public static void Square(uint[] x, uint[] z) -- cgit 1.4.1