Fix 64-bit multiply (not used)

- correct weird shift lengths in 32-bit multiply (no bug)

2 files changed, 73 insertions, 5 deletions

diff --git a/crypto/src/crypto/modes/gcm/GcmUtilities.cs b/crypto/src/crypto/modes/gcm/GcmUtilities.cs
index de41d88f4..d8ab2ca73 100644
--- a/crypto/src/crypto/modes/gcm/GcmUtilities.cs
+++ b/crypto/src/crypto/modes/gcm/GcmUtilities.cs
@@ -46,6 +46,13 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
             return tmp;
         }
 
+        internal static ulong[] OneAsUlongs()
+        {
+            ulong[] tmp = new ulong[2];
+            tmp[0] = 1UL << 63;
+            return tmp;
+        }
+
         internal static byte[] AsBytes(uint[] x)
         {
             return Pack.UInt32_To_BE(x);
@@ -56,6 +63,18 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
             Pack.UInt32_To_BE(x, z, 0);
         }
 
+        internal static byte[] AsBytes(ulong[] x)
+        {
+            byte[] z = new byte[16];
+            Pack.UInt64_To_BE(x, z, 0);
+            return z;
+        }
+
+        internal static void AsBytes(ulong[] x, byte[] z)
+        {
+            Pack.UInt64_To_BE(x, z, 0);
+        }
+
         internal static uint[] AsUints(byte[] bs)
         {
             uint[] output = new uint[4];
@@ -68,6 +87,18 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
             Pack.BE_To_UInt32(bs, 0, output);
         }
 
+        internal static ulong[] AsUlongs(byte[] x)
+        {
+            ulong[] z = new ulong[2];
+            Pack.BE_To_UInt64(x, 0, z);
+            return z;
+        }
+
+        public static void AsUlongs(byte[] x, ulong[] z)
+        {
+            Pack.BE_To_UInt64(x, 0, z);
+        }
+
         internal static void Multiply(byte[] x, byte[] y)
         {
             uint[] t1 = GcmUtilities.AsUints(x);
@@ -80,7 +111,7 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
         {
             uint r00 = x[0], r01 = x[1], r02 = x[2], r03 = x[3];
             uint r10 = 0, r11 = 0, r12 = 0, r13 = 0;
-        
+
             for (int i = 0; i < 4; ++i)
             {
                 int bits = (int)y[i];
@@ -93,9 +124,9 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
                     r13 ^= (r03 & m1);
 
                     uint m2 = (uint)((int)(r03 << 31) >> 8);
-                    r03 = (r03 >> 1) | (r02 << 63);
-                    r02 = (r02 >> 1) | (r01 << 63);
-                    r01 = (r01 >> 1) | (r00 << 63);
+                    r03 = (r03 >> 1) | (r02 << 31);
+                    r02 = (r02 >> 1) | (r01 << 31);
+                    r01 = (r01 >> 1) | (r00 << 31);
                     r00 = (r00 >> 1) ^ (m2 & E1);
                 }
             }
@@ -119,7 +150,7 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
                     r10 ^= (r00 & m1);
                     r11 ^= (r01 & m1);
 
-                    ulong m2 = (r01 << 63) >> 8;
+                    ulong m2 = (ulong)((long)(r01 << 63) >> 8);
                     r01 = (r01 >> 1) | (r00 << 63);
                     r00 = (r00 >> 1) ^ (m2 & E1L);
                 }
@@ -272,5 +303,17 @@ namespace Org.BouncyCastle.Crypto.Modes.Gcm
             z[2] = x[2] ^ y[2];
             z[3] = x[3] ^ y[3];
         }
+
+        internal static void Xor(ulong[] x, ulong[] y)
+        {
+            x[0] ^= y[0];
+            x[1] ^= y[1];
+        }
+
+        internal static void Xor(ulong[] x, ulong[] y, ulong[] z)
+        {
+            z[0] = x[0] ^ y[0];
+            z[1] = x[1] ^ y[1];
+        }
     }
 }
diff --git a/crypto/src/crypto/util/Pack.cs b/crypto/src/crypto/util/Pack.cs
index 087cb7cea..dc00ab450 100644
--- a/crypto/src/crypto/util/Pack.cs
+++ b/crypto/src/crypto/util/Pack.cs
@@ -117,6 +117,22 @@ namespace Org.BouncyCastle.Crypto.Utilities
             UInt32_To_BE((uint)(n), bs, off + 4);
         }
 
+        internal static byte[] UInt64_To_BE(ulong[] ns)
+        {
+            byte[] bs = new byte[8 * ns.Length];
+            UInt64_To_BE(ns, bs, 0);
+            return bs;
+        }
+
+        internal static void UInt64_To_BE(ulong[] ns, byte[] bs, int off)
+        {
+            for (int i = 0; i < ns.Length; ++i)
+            {
+                UInt64_To_BE(ns[i], bs, off);
+                off += 8;
+            }
+        }
+
         internal static ulong BE_To_UInt64(byte[] bs)
         {
             uint hi = BE_To_UInt32(bs);
@@ -131,6 +147,15 @@ namespace Org.BouncyCastle.Crypto.Utilities
             return ((ulong)hi << 32) | (ulong)lo;
         }
 
+        internal static void BE_To_UInt64(byte[] bs, int off, ulong[] ns)
+        {
+            for (int i = 0; i < ns.Length; ++i)
+            {
+                ns[i] = BE_To_UInt64(bs, off);
+                off += 8;
+            }
+        }
+
         internal static void UInt16_To_LE(ushort n, byte[] bs)
         {
             bs[0] = (byte)(n);