diff options
| -rw-r--r-- | crypto/src/crypto/modes/gcm/BasicGcmMultiplier.cs | 5 | ||||
| -rw-r--r-- | crypto/src/crypto/modes/gcm/GcmUtilities.cs | 38 |
2 files changed, 4 insertions, 39 deletions
diff --git a/crypto/src/crypto/modes/gcm/BasicGcmMultiplier.cs b/crypto/src/crypto/modes/gcm/BasicGcmMultiplier.cs index bf19e173d..c93318524 100644 --- a/crypto/src/crypto/modes/gcm/BasicGcmMultiplier.cs +++ b/crypto/src/crypto/modes/gcm/BasicGcmMultiplier.cs @@ -14,7 +14,10 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm public void MultiplyH(byte[] x) { - GcmUtilities.Multiply(x, ref H); + GcmUtilities.FieldElement T; + GcmUtilities.AsFieldElement(x, out T); + GcmUtilities.Multiply(ref T, ref H); + GcmUtilities.AsBytes(ref T, x); } } } diff --git a/crypto/src/crypto/modes/gcm/GcmUtilities.cs b/crypto/src/crypto/modes/gcm/GcmUtilities.cs index 5bbf78d0a..3deed2fc1 100644 --- a/crypto/src/crypto/modes/gcm/GcmUtilities.cs +++ b/crypto/src/crypto/modes/gcm/GcmUtilities.cs @@ -161,44 +161,6 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm AsBytes(t1, x); } - internal static void Multiply(byte[] x, ref FieldElement y) - { - /* - * "Three-way recursion" as described in "Batch binary Edwards", Daniel J. Bernstein. - * - * Without access to the high part of a 64x64 product x * y, we use a bit reversal to calculate it: - * rev(x) * rev(y) == rev((x * y) << 1) - */ - - ulong x0 = Pack.BE_To_UInt64(x, 0); - ulong x1 = Pack.BE_To_UInt64(x, 8); - ulong y0 = y.n0, y1 = y.n1; - ulong x0r = Longs.Reverse(x0), x1r = Longs.Reverse(x1); - ulong y0r = Longs.Reverse(y0), y1r = Longs.Reverse(y1); - - ulong h0 = Longs.Reverse(ImplMul64(x0r, y0r)); - ulong h1 = ImplMul64(x0, y0) << 1; - ulong h2 = Longs.Reverse(ImplMul64(x1r, y1r)); - ulong h3 = ImplMul64(x1, y1) << 1; - ulong h4 = Longs.Reverse(ImplMul64(x0r ^ x1r, y0r ^ y1r)); - ulong h5 = ImplMul64(x0 ^ x1, y0 ^ y1) << 1; - - ulong z0 = h0; - ulong z1 = h1 ^ h0 ^ h2 ^ h4; - ulong z2 = h2 ^ h1 ^ h3 ^ h5; - ulong z3 = h3; - - z1 ^= z3 ^ (z3 >> 1) ^ (z3 >> 2) ^ (z3 >> 7); -// z2 ^= (z3 << 63) ^ (z3 << 62) ^ (z3 << 57); - z2 ^= (z3 << 62) ^ (z3 << 57); - - z0 ^= z2 ^ (z2 >> 1) ^ (z2 >> 2) ^ (z2 >> 7); - z1 ^= (z2 << 63) ^ (z2 << 62) ^ (z2 << 57); - - Pack.UInt64_To_BE(z0, x, 0); - Pack.UInt64_To_BE(z1, x, 8); - } - internal static void Multiply(uint[] x, uint[] y) { uint y0 = y[0], y1 = y[1], y2 = y[2], y3 = y[3]; |