Math.Raw support for custom binary curves

- Also migrate the 'raw' stuff into Math.Raw following Java build

1 files changed, 100 insertions, 0 deletions

diff --git a/crypto/src/math/raw/Nat448.cs b/crypto/src/math/raw/Nat448.cs
new file mode 100644
index 000000000..52a253f1b
--- /dev/null
+++ b/crypto/src/math/raw/Nat448.cs
@@ -0,0 +1,100 @@
+using System;
+using System.Diagnostics;
+
+using Org.BouncyCastle.Crypto.Utilities;
+
+namespace Org.BouncyCastle.Math.Raw
+{
+    internal abstract class Nat448
+    {
+        public static void Copy64(ulong[] x, ulong[] z)
+        {
+            z[0] = x[0];
+            z[1] = x[1];
+            z[2] = x[2];
+            z[3] = x[3];
+            z[4] = x[4];
+            z[5] = x[5];
+            z[6] = x[6];
+        }
+
+        public static ulong[] Create64()
+        {
+            return new ulong[7];
+        }
+
+        public static ulong[] CreateExt64()
+        {
+            return new ulong[14];
+        }
+
+        public static bool Eq64(ulong[] x, ulong[] y)
+        {
+            for (int i = 6; i >= 0; --i)
+            {
+                if (x[i] != y[i])
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        public static ulong[] FromBigInteger64(BigInteger x)
+        {
+            if (x.SignValue < 0 || x.BitLength > 448)
+                throw new ArgumentException();
+
+            ulong[] z = Create64();
+            int i = 0;
+            while (x.SignValue != 0)
+            {
+                z[i++] = (ulong)x.LongValue;
+                x = x.ShiftRight(64);
+            }
+            return z;
+        }
+
+        public static bool IsOne64(ulong[] x)
+        {
+            if (x[0] != 1UL)
+            {
+                return false;
+            }
+            for (int i = 1; i < 7; ++i)
+            {
+                if (x[i] != 0UL)
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        public static bool IsZero64(ulong[] x)
+        {
+            for (int i = 0; i < 7; ++i)
+            {
+                if (x[i] != 0UL)
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        public static BigInteger ToBigInteger64(ulong[] x)
+        {
+            byte[] bs = new byte[56];
+            for (int i = 0; i < 7; ++i)
+            {
+                ulong x_i = x[i];
+                if (x_i != 0L)
+                {
+                    Pack.UInt64_To_BE(x_i, bs, (6 - i) << 3);
+                }
+            }
+            return new BigInteger(1, bs);
+        }
+    }
+}