1 files changed, 90 insertions, 0 deletions
diff --git a/Crypto/src/crypto/modes/gcm/Tables8kGcmMultiplier.cs b/Crypto/src/crypto/modes/gcm/Tables8kGcmMultiplier.cs
new file mode 100644
index 000000000..91d58fab8
--- /dev/null
+++ b/Crypto/src/crypto/modes/gcm/Tables8kGcmMultiplier.cs
@@ -0,0 +1,90 @@
+using System;
+
+using Org.BouncyCastle.Crypto.Utilities;
+
+namespace Org.BouncyCastle.Crypto.Modes.Gcm
+{
+	public class Tables8kGcmMultiplier
+		: IGcmMultiplier
+	{
+		private readonly uint[][][] M = new uint[32][][];
+		
+		public void Init(byte[] H)
+		{
+			M[0] = new uint[16][];
+			M[1] = new uint[16][];
+			M[0][0] = new uint[4];
+			M[1][0] = new uint[4];
+			M[1][8] = GcmUtilities.AsUints(H);
+
+			for (int j = 4; j >= 1; j >>= 1)
+			{
+				uint[] tmp = (uint[])M[1][j + j].Clone();
+				GcmUtilities.MultiplyP(tmp);
+				M[1][j] = tmp;
+			}
+
+			{
+				uint[] tmp = (uint[])M[1][1].Clone();
+				GcmUtilities.MultiplyP(tmp);
+				M[0][8] = tmp;
+			}
+
+			for (int j = 4; j >= 1; j >>= 1)
+			{
+				uint[] tmp = (uint[])M[0][j + j].Clone();
+				GcmUtilities.MultiplyP(tmp);
+				M[0][j] = tmp;
+			}
+
+			for (int i = 0;;)
+			{
+				for (int j = 2; j < 16; j += j)
+				{
+					for (int k = 1; k < j; ++k)
+					{
+						uint[] tmp = (uint[])M[i][j].Clone();
+						GcmUtilities.Xor(tmp, M[i][k]);
+						M[i][j + k] = tmp;
+					}
+				}
+
+				if (++i == 32) return;
+
+				if (i > 1)
+				{
+					M[i] = new uint[16][];
+					M[i][0] = new uint[4];
+					for(int j = 8; j > 0; j >>= 1)
+					{
+						uint[] tmp = (uint[])M[i - 2][j].Clone();
+						GcmUtilities.MultiplyP8(tmp);
+						M[i][j] = tmp;
+					}
+				}
+			}
+		}
+
+		public void MultiplyH(byte[] x)
+		{
+			uint[] z = new uint[4];
+			for (int i = 15; i >= 0; --i)
+			{
+				//GcmUtilities.Xor(z, M[i + i][x[i] & 0x0f]);
+				uint[] m = M[i + i][x[i] & 0x0f];
+				z[0] ^= m[0];
+				z[1] ^= m[1];
+				z[2] ^= m[2];
+				z[3] ^= m[3];
+				//GcmUtilities.Xor(z, M[i + i + 1][(x[i] & 0xf0) >> 4]);
+				m = M[i + i + 1][(x[i] & 0xf0) >> 4];
+				z[0] ^= m[0];
+				z[1] ^= m[1];
+				z[2] ^= m[2];
+				z[3] ^= m[3];
+			}
+
+			Pack.UInt32_To_BE(z, x, 0);
+		}
+	}
+}