diff options
| -rw-r--r-- | crypto/src/pqc/crypto/cmce/Benes.cs | 87 | ||||
| -rw-r--r-- | crypto/src/pqc/crypto/cmce/GF.cs | 6 |
2 files changed, 37 insertions, 56 deletions
diff --git a/crypto/src/pqc/crypto/cmce/Benes.cs b/crypto/src/pqc/crypto/cmce/Benes.cs index 455d7946f..a0c38980b 100644 --- a/crypto/src/pqc/crypto/cmce/Benes.cs +++ b/crypto/src/pqc/crypto/cmce/Benes.cs @@ -1,11 +1,18 @@ +using System; + +using Org.BouncyCastle.Math.Raw; + namespace Org.BouncyCastle.Pqc.Crypto.Cmce { internal abstract class Benes { - protected int SYS_N; - protected int SYS_T; - protected int GFBITS; + private static readonly ulong[] TransposeMasks = { 0x5555555555555555UL, 0x3333333333333333UL, + 0x0F0F0F0F0F0F0F0FUL, 0x00FF00FF00FF00FFUL, 0x0000FFFF0000FFFFUL, 0x00000000FFFFFFFFUL }; + + protected readonly int SYS_N; + protected readonly int SYS_T; + protected readonly int GFBITS; internal Benes(int n, int t, int m) { @@ -18,72 +25,44 @@ namespace Org.BouncyCastle.Pqc.Crypto.Cmce /* outputput: output, transpose of in */ internal static void Transpose64x64(ulong[] output, ulong[] input) { - int i, j, s, d; - - ulong x, y; - ulong[,] masks = - { - {0x5555555555555555L, 0xAAAAAAAAAAAAAAAAL}, - {0x3333333333333333L, 0xCCCCCCCCCCCCCCCCL}, - {0x0F0F0F0F0F0F0F0FL, 0xF0F0F0F0F0F0F0F0L}, - {0x00FF00FF00FF00FFL, 0xFF00FF00FF00FF00L}, - {0x0000FFFF0000FFFFL, 0xFFFF0000FFFF0000L}, - {0x00000000FFFFFFFFL, 0xFFFFFFFF00000000L} - }; + Transpose64x64(output, input, 0); + } - for (i = 0; i < 64; i++) - output[i] = input[i]; + internal static void Transpose64x64(ulong[] output, ulong[] input, int offset) + { + Array.Copy(input, offset, output, offset, 64); - for (d = 5; d >= 0; d--) + int d = 5; + do { - s = 1 << d; - for (i = 0; i < 64; i += s * 2) + ulong m = TransposeMasks[d]; + int s = 1 << d; + for (int i = offset; i < offset + 64; i += s * 2) { - for (j = i; j < i + s; j++) + for (int j = i; j < i + s; j += 4) { - x = (output[j] & masks[d, 0]) | ((output[j + s] & masks[d, 0]) << s); - y = ((output[j] & masks[d, 1]) >> s) | (output[j + s] & masks[d, 1]); - - output[j + 0] = x; - output[j + s] = y; + Bits.BitPermuteStep2(ref output[j + s + 0], ref output[j + 0], m, s); + Bits.BitPermuteStep2(ref output[j + s + 1], ref output[j + 1], m, s); + Bits.BitPermuteStep2(ref output[j + s + 2], ref output[j + 2], m, s); + Bits.BitPermuteStep2(ref output[j + s + 3], ref output[j + 3], m, s); } } } - } - - internal static void Transpose64x64(ulong[] output, ulong[] input, int offset) - { - int i, j, s, d; + while (--d >= 2); - ulong x, y; - ulong[,] masks = + do { - {0x5555555555555555L, 0xAAAAAAAAAAAAAAAAL}, - {0x3333333333333333L, 0xCCCCCCCCCCCCCCCCL}, - {0x0F0F0F0F0F0F0F0FL, 0xF0F0F0F0F0F0F0F0L}, - {0x00FF00FF00FF00FFL, 0xFF00FF00FF00FF00L}, - {0x0000FFFF0000FFFFL, 0xFFFF0000FFFF0000L}, - {0x00000000FFFFFFFFL, 0xFFFFFFFF00000000L} - }; - - for (i = 0; i < 64; i++) - output[i + offset] = input[i + offset]; - - for (d = 5; d >= 0; d--) - { - s = 1 << d; - for (i = 0; i < 64; i += s * 2) + ulong m = TransposeMasks[d]; + int s = 1 << d; + for (int i = offset; i < offset + 64; i += s * 2) { - for (j = i; j < i + s; j++) + for (int j = i; j < i + s; ++j) { - x = (output[j + offset] & masks[d, 0]) | ((output[j + s + offset] & masks[d, 0]) << s); - y = ((output[j + offset] & masks[d, 1]) >> s) | (output[j + s + offset] & masks[d, 1]); - - output[j + 0 + offset] = x; - output[j + s + offset] = y; + Bits.BitPermuteStep2(ref output[j + s], ref output[j], m, s); } } } + while (--d >= 0); } internal abstract void SupportGen(ushort[] s, byte[] c); diff --git a/crypto/src/pqc/crypto/cmce/GF.cs b/crypto/src/pqc/crypto/cmce/GF.cs index 8c5123107..687624ba2 100644 --- a/crypto/src/pqc/crypto/cmce/GF.cs +++ b/crypto/src/pqc/crypto/cmce/GF.cs @@ -50,7 +50,8 @@ namespace Org.BouncyCastle.Pqc.Crypto.Cmce temp[i - length + poly[j]] ^= temp_i; } { - temp[i - length] ^= GFMulExt(GFReduce(temp_i), 2); + // NOTE: Safe because GFReduce allows up to 24 bits, but GFMulExt(Par) only produces 23. + temp[i - length] ^= temp_i << 1; } } @@ -79,7 +80,8 @@ namespace Org.BouncyCastle.Pqc.Crypto.Cmce temp[i - length + poly[j]] ^= temp_i; } { - temp[i - length] ^= GFMulExt(GFReduce(temp_i), 2); + // NOTE: Safe because GFReduce allows up to 24 bits, but GFSqExt only produces 23. + temp[i - length] ^= temp_i << 1; } } |