diff --git a/crypto/src/crypto/engines/NoekeonEngine.cs b/crypto/src/crypto/engines/NoekeonEngine.cs
index f64be50ba..65f6e3878 100644
--- a/crypto/src/crypto/engines/NoekeonEngine.cs
+++ b/crypto/src/crypto/engines/NoekeonEngine.cs
@@ -12,25 +12,13 @@ namespace Org.BouncyCastle.Crypto.Engines
public class NoekeonEngine
: IBlockCipher
{
- private const int GenericSize = 16; // Block and key size, as well as the amount of rounds.
+ // Block and key size, as well as the amount of rounds.
+ private const int Size = 16;
- private static readonly uint[] nullVector =
- {
- 0x00, 0x00, 0x00, 0x00 // Used in decryption
- };
-
- private static readonly uint[] roundConstants =
- {
- 0x80, 0x1b, 0x36, 0x6c,
- 0xd8, 0xab, 0x4d, 0x9a,
- 0x2f, 0x5e, 0xbc, 0x63,
- 0xc6, 0x97, 0x35, 0x6a,
- 0xd4
- };
+ private static readonly byte[] RoundConstants = { 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e,
+ 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4 };
- private uint[] state = new uint[4], // a
- subKeys = new uint[4], // k
- decryptKeys = new uint[4];
+ private readonly uint[] k = new uint[4];
private bool _initialised, _forEncryption;
@@ -55,7 +43,7 @@ namespace Org.BouncyCastle.Crypto.Engines
public virtual int GetBlockSize()
{
- return GenericSize;
+ return Size;
}
/**
@@ -66,20 +54,38 @@ namespace Org.BouncyCastle.Crypto.Engines
* @exception ArgumentException if the params argument is
* inappropriate.
*/
- public virtual void Init(
- bool forEncryption,
- ICipherParameters parameters)
+ public virtual void Init(bool forEncryption, ICipherParameters parameters)
{
if (!(parameters is KeyParameter))
throw new ArgumentException("Invalid parameters passed to Noekeon init - "
+ Platform.GetTypeName(parameters), "parameters");
- _forEncryption = forEncryption;
- _initialised = true;
+ this._forEncryption = forEncryption;
+ this._initialised = true;
KeyParameter p = (KeyParameter) parameters;
- setKey(p.GetKey());
+ Pack.BE_To_UInt32(p.GetKey(), 0, k, 0, 4);
+
+ if (!forEncryption)
+ {
+ // theta(k, new uint[]{ 0x00, 0x00, 0x00, 0x00 });
+ {
+ uint a0 = k[0], a1 = k[1], a2 = k[2], a3 = k[3];
+
+ uint t = a0 ^ a2;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a1 ^= t;
+ a3 ^= t;
+
+ t = a1 ^ a3;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a0 ^= t;
+ a2 ^= t;
+
+ k[0] = a0; k[1] = a1; k[2] = a2; k[3] = a3;
+ }
+ }
}
public virtual int ProcessBlock(
@@ -91,151 +97,158 @@ namespace Org.BouncyCastle.Crypto.Engines
if (!_initialised)
throw new InvalidOperationException(AlgorithmName + " not initialised");
- Check.DataLength(input, inOff, GenericSize, "input buffer too short");
- Check.OutputLength(output, outOff, GenericSize, "output buffer too short");
+ Check.DataLength(input, inOff, Size, "input buffer too short");
+ Check.OutputLength(output, outOff, Size, "output buffer too short");
return _forEncryption
- ? encryptBlock(input, inOff, output, outOff)
- : decryptBlock(input, inOff, output, outOff);
+ ? EncryptBlock(input, inOff, output, outOff)
+ : DecryptBlock(input, inOff, output, outOff);
}
public virtual void Reset()
{
- // TODO This should do something in case the encryption is aborted
}
- /**
- * Re-key the cipher.
- *
- * @param key the key to be used
- */
- private void setKey(byte[] key)
+ private int EncryptBlock(byte[] input, int inOff, byte[] output, int outOff)
{
- subKeys[0] = Pack.BE_To_UInt32(key, 0);
- subKeys[1] = Pack.BE_To_UInt32(key, 4);
- subKeys[2] = Pack.BE_To_UInt32(key, 8);
- subKeys[3] = Pack.BE_To_UInt32(key, 12);
- }
+ uint a0 = Pack.BE_To_UInt32(input, inOff);
+ uint a1 = Pack.BE_To_UInt32(input, inOff + 4);
+ uint a2 = Pack.BE_To_UInt32(input, inOff + 8);
+ uint a3 = Pack.BE_To_UInt32(input, inOff + 12);
- private int encryptBlock(
- byte[] input,
- int inOff,
- byte[] output,
- int outOff)
- {
- state[0] = Pack.BE_To_UInt32(input, inOff);
- state[1] = Pack.BE_To_UInt32(input, inOff+4);
- state[2] = Pack.BE_To_UInt32(input, inOff+8);
- state[3] = Pack.BE_To_UInt32(input, inOff+12);
+ uint k0 = k[0], k1 = k[1], k2 = k[2], k3 = k[3];
- int i;
- for (i = 0; i < GenericSize; i++)
+ int round = 0;
+ uint t;
+ for (;;)
{
- state[0] ^= roundConstants[i];
- theta(state, subKeys);
- pi1(state);
- gamma(state);
- pi2(state);
+ a0 ^= RoundConstants[round];
+
+ // theta(a, k);
+ {
+ t = a0 ^ a2;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a1 ^= t;
+ a3 ^= t;
+
+ a0 ^= k0;
+ a1 ^= k1;
+ a2 ^= k2;
+ a3 ^= k3;
+
+ t = a1 ^ a3;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a0 ^= t;
+ a2 ^= t;
+ }
+
+ if (++round > Size)
+ break;
+
+ // pi1(a);
+ {
+ a1 = Integers.RotateLeft(a1, 1);
+ a2 = Integers.RotateLeft(a2, 5);
+ a3 = Integers.RotateLeft(a3, 2);
+ }
+
+ // gamma(a);
+ {
+ a1 ^= ~a3 & ~a2;
+ a0 ^= a2 & a1;
+
+ t = a3; a3 = a0; a0 = t;
+ a2 ^= a0 ^ a1 ^ a3;
+
+ a1 ^= ~a3 & ~a2;
+ a0 ^= a2 & a1;
+ }
+
+ // pi2(a);
+ {
+ a1 = Integers.RotateLeft(a1, 31);
+ a2 = Integers.RotateLeft(a2, 27);
+ a3 = Integers.RotateLeft(a3, 30);
+ }
}
- state[0] ^= roundConstants[i];
- theta(state, subKeys);
-
- Pack.UInt32_To_BE(state[0], output, outOff);
- Pack.UInt32_To_BE(state[1], output, outOff+4);
- Pack.UInt32_To_BE(state[2], output, outOff+8);
- Pack.UInt32_To_BE(state[3], output, outOff+12);
+ Pack.UInt32_To_BE(a0, output, outOff);
+ Pack.UInt32_To_BE(a1, output, outOff + 4);
+ Pack.UInt32_To_BE(a2, output, outOff + 8);
+ Pack.UInt32_To_BE(a3, output, outOff + 12);
- return GenericSize;
+ return Size;
}
- private int decryptBlock(
- byte[] input,
- int inOff,
- byte[] output,
- int outOff)
+ private int DecryptBlock(byte[] input, int inOff, byte[] output, int outOff)
{
- state[0] = Pack.BE_To_UInt32(input, inOff);
- state[1] = Pack.BE_To_UInt32(input, inOff+4);
- state[2] = Pack.BE_To_UInt32(input, inOff+8);
- state[3] = Pack.BE_To_UInt32(input, inOff+12);
+ uint a0 = Pack.BE_To_UInt32(input, inOff);
+ uint a1 = Pack.BE_To_UInt32(input, inOff + 4);
+ uint a2 = Pack.BE_To_UInt32(input, inOff + 8);
+ uint a3 = Pack.BE_To_UInt32(input, inOff + 12);
- Array.Copy(subKeys, 0, decryptKeys, 0, subKeys.Length);
- theta(decryptKeys, nullVector);
+ uint k0 = k[0], k1 = k[1], k2 = k[2], k3 = k[3];
- int i;
- for (i = GenericSize; i > 0; i--)
+ int round = Size;
+ uint t;
+ for (;;)
{
- theta(state, decryptKeys);
- state[0] ^= roundConstants[i];
- pi1(state);
- gamma(state);
- pi2(state);
+ // theta(a, k);
+ {
+ t = a0 ^ a2;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a1 ^= t;
+ a3 ^= t;
+
+ a0 ^= k0;
+ a1 ^= k1;
+ a2 ^= k2;
+ a3 ^= k3;
+
+ t = a1 ^ a3;
+ t ^= Integers.RotateLeft(t, 8) ^ Integers.RotateLeft(t, 24);
+ a0 ^= t;
+ a2 ^= t;
+ }
+
+ a0 ^= RoundConstants[round];
+
+ if (--round < 0)
+ break;
+
+ // pi1(a);
+ {
+ a1 = Integers.RotateLeft(a1, 1);
+ a2 = Integers.RotateLeft(a2, 5);
+ a3 = Integers.RotateLeft(a3, 2);
+ }
+
+ // gamma(a);
+ {
+ a1 ^= ~a3 & ~a2;
+ a0 ^= a2 & a1;
+
+ t = a3; a3 = a0; a0 = t;
+ a2 ^= a0 ^ a1 ^ a3;
+
+ a1 ^= ~a3 & ~a2;
+ a0 ^= a2 & a1;
+ }
+
+ // pi2(a);
+ {
+ a1 = Integers.RotateLeft(a1, 31);
+ a2 = Integers.RotateLeft(a2, 27);
+ a3 = Integers.RotateLeft(a3, 30);
+ }
}
- theta(state, decryptKeys);
- state[0] ^= roundConstants[i];
+ Pack.UInt32_To_BE(a0, output, outOff);
+ Pack.UInt32_To_BE(a1, output, outOff + 4);
+ Pack.UInt32_To_BE(a2, output, outOff + 8);
+ Pack.UInt32_To_BE(a3, output, outOff + 12);
- Pack.UInt32_To_BE(state[0], output, outOff);
- Pack.UInt32_To_BE(state[1], output, outOff+4);
- Pack.UInt32_To_BE(state[2], output, outOff+8);
- Pack.UInt32_To_BE(state[3], output, outOff+12);
-
- return GenericSize;
- }
-
- private void gamma(uint[] a)
- {
- a[1] ^= ~a[3] & ~a[2];
- a[0] ^= a[2] & a[1];
-
- uint tmp = a[3];
- a[3] = a[0];
- a[0] = tmp;
- a[2] ^= a[0]^a[1]^a[3];
-
- a[1] ^= ~a[3] & ~a[2];
- a[0] ^= a[2] & a[1];
- }
-
- private void theta(uint[] a, uint[] k)
- {
- uint tmp;
- tmp = a[0]^a[2];
- tmp ^= rotl(tmp,8)^rotl(tmp,24);
- a[1] ^= tmp;
- a[3] ^= tmp;
-
- for (int i = 0; i < 4; i++)
- {
- a[i] ^= k[i];
- }
-
- tmp = a[1]^a[3];
- tmp ^= rotl(tmp,8)^rotl(tmp,24);
- a[0] ^= tmp;
- a[2] ^= tmp;
- }
-
- private void pi1(uint[] a)
- {
- a[1] = rotl(a[1], 1);
- a[2] = rotl(a[2], 5);
- a[3] = rotl(a[3], 2);
- }
-
- private void pi2(uint[] a)
- {
- a[1] = rotl(a[1], 31);
- a[2] = rotl(a[2], 27);
- a[3] = rotl(a[3], 30);
- }
-
- // Helpers
-
- private uint rotl(uint x, int y)
- {
- return (x << y) | (x >> (32-y));
+ return Size;
}
}
}
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