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| author | Peter Dettman <peter.dettman@bouncycastle.org> | 2014-02-26 20:13:52 +0700 |
|---|---|---|
| committer | Peter Dettman <peter.dettman@bouncycastle.org> | 2014-02-26 20:13:52 +0700 |
| commit | 57d401f1c1919e507eb42ac0964a8b5d61ee6049 (patch) | |
| tree | 413d79b8d57700b9270ab4533787474910e44822 /crypto/src/math/ec/custom/sec/Nat224.cs | |
| parent | Optimize Sqrt() for custom curve secp224k1 (diff) | |
| download | BouncyCastle.NET-ed25519-57d401f1c1919e507eb42ac0964a8b5d61ee6049.tar.xz | |
Optimization for custom curve reduction when only a few bits need reducing; used to delay reduction in point doubling.
Diffstat (limited to 'crypto/src/math/ec/custom/sec/Nat224.cs')
| -rw-r--r-- | crypto/src/math/ec/custom/sec/Nat224.cs | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/crypto/src/math/ec/custom/sec/Nat224.cs b/crypto/src/math/ec/custom/sec/Nat224.cs index 72950e8a6..a391fc248 100644 --- a/crypto/src/math/ec/custom/sec/Nat224.cs +++ b/crypto/src/math/ec/custom/sec/Nat224.cs @@ -730,6 +730,23 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec return c == 0 ? 0 : Inc(z, zOff + 4); } + public static uint Mul33WordAdd(uint x, uint y, uint[] z, int zOff) + { + Debug.Assert(x >> 31 == 0); + Debug.Assert(zOff <= 4); + ulong c = 0, yVal = y; + c += yVal * x + z[zOff + 0]; + z[zOff + 0] = (uint)c; + c >>= 32; + c += yVal + z[zOff + 1]; + z[zOff + 1] = (uint)c; + c >>= 32; + c += z[zOff + 2]; + z[zOff + 2] = (uint)c; + c >>= 32; + return c == 0 ? 0 : Inc(z, zOff + 3); + } + public static uint MulWordDwordAdd(uint x, ulong y, uint[] z, int zOff) { Debug.Assert(zOff <= 4); |