diff --git a/Crypto/src/crypto/engines/TEAEngine.cs b/Crypto/src/crypto/engines/TEAEngine.cs
new file mode 100644
index 000000000..582dd0f73
--- /dev/null
+++ b/Crypto/src/crypto/engines/TEAEngine.cs
@@ -0,0 +1,168 @@
+using System;
+
+using Org.BouncyCastle.Crypto.Parameters;
+using Org.BouncyCastle.Crypto.Utilities;
+
+namespace Org.BouncyCastle.Crypto.Engines
+{
+ /**
+ * An TEA engine.
+ */
+ public class TeaEngine
+ : IBlockCipher
+ {
+ private const int
+ rounds = 32,
+ block_size = 8;
+// key_size = 16,
+
+ private const uint
+ delta = 0x9E3779B9,
+ d_sum = 0xC6EF3720; // sum on decrypt
+
+ /*
+ * the expanded key array of 4 subkeys
+ */
+ private uint _a, _b, _c, _d;
+ private bool _initialised;
+ private bool _forEncryption;
+
+ /**
+ * Create an instance of the TEA encryption algorithm
+ * and set some defaults
+ */
+ public TeaEngine()
+ {
+ _initialised = false;
+ }
+
+ public string AlgorithmName
+ {
+ get { return "TEA"; }
+ }
+
+ public bool IsPartialBlockOkay
+ {
+ get { return false; }
+ }
+
+ public int GetBlockSize()
+ {
+ return block_size;
+ }
+
+ /**
+ * initialise
+ *
+ * @param forEncryption whether or not we are for encryption.
+ * @param params the parameters required to set up the cipher.
+ * @exception ArgumentException if the params argument is
+ * inappropriate.
+ */
+ public void Init(
+ bool forEncryption,
+ ICipherParameters parameters)
+ {
+ if (!(parameters is KeyParameter))
+ {
+ throw new ArgumentException("invalid parameter passed to TEA init - "
+ + parameters.GetType().FullName);
+ }
+
+ _forEncryption = forEncryption;
+ _initialised = true;
+
+ KeyParameter p = (KeyParameter) parameters;
+
+ setKey(p.GetKey());
+ }
+
+ public int ProcessBlock(
+ byte[] inBytes,
+ int inOff,
+ byte[] outBytes,
+ int outOff)
+ {
+ if (!_initialised)
+ throw new InvalidOperationException(AlgorithmName + " not initialised");
+
+ if ((inOff + block_size) > inBytes.Length)
+ throw new DataLengthException("input buffer too short");
+
+ if ((outOff + block_size) > outBytes.Length)
+ throw new DataLengthException("output buffer too short");
+
+ return _forEncryption
+ ? encryptBlock(inBytes, inOff, outBytes, outOff)
+ : decryptBlock(inBytes, inOff, outBytes, outOff);
+ }
+
+ public void Reset()
+ {
+ }
+
+ /**
+ * Re-key the cipher.
+ *
+ * @param key the key to be used
+ */
+ private void setKey(
+ byte[] key)
+ {
+ _a = Pack.BE_To_UInt32(key, 0);
+ _b = Pack.BE_To_UInt32(key, 4);
+ _c = Pack.BE_To_UInt32(key, 8);
+ _d = Pack.BE_To_UInt32(key, 12);
+ }
+
+ private int encryptBlock(
+ byte[] inBytes,
+ int inOff,
+ byte[] outBytes,
+ int outOff)
+ {
+ // Pack bytes into integers
+ uint v0 = Pack.BE_To_UInt32(inBytes, inOff);
+ uint v1 = Pack.BE_To_UInt32(inBytes, inOff + 4);
+
+ uint sum = 0;
+
+ for (int i = 0; i != rounds; i++)
+ {
+ sum += delta;
+ v0 += ((v1 << 4) + _a) ^ (v1 + sum) ^ ((v1 >> 5) + _b);
+ v1 += ((v0 << 4) + _c) ^ (v0 + sum) ^ ((v0 >> 5) + _d);
+ }
+
+ Pack.UInt32_To_BE(v0, outBytes, outOff);
+ Pack.UInt32_To_BE(v1, outBytes, outOff + 4);
+
+ return block_size;
+ }
+
+ private int decryptBlock(
+ byte[] inBytes,
+ int inOff,
+ byte[] outBytes,
+ int outOff)
+ {
+ // Pack bytes into integers
+ uint v0 = Pack.BE_To_UInt32(inBytes, inOff);
+ uint v1 = Pack.BE_To_UInt32(inBytes, inOff + 4);
+
+ uint sum = d_sum;
+
+ for (int i = 0; i != rounds; i++)
+ {
+ v1 -= ((v0 << 4) + _c) ^ (v0 + sum) ^ ((v0 >> 5) + _d);
+ v0 -= ((v1 << 4) + _a) ^ (v1 + sum) ^ ((v1 >> 5) + _b);
+ sum -= delta;
+ }
+
+ Pack.UInt32_To_BE(v0, outBytes, outOff);
+ Pack.UInt32_To_BE(v1, outBytes, outOff + 4);
+
+ return block_size;
+ }
+ }
+}
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