Initial Commit

iTechSharp/srcbc/crypto/engines/RsaEngine.cs

@@ -0,0 +1,78 @@
+using System;
+
+namespace Org.BouncyCastle.Crypto.Engines
+{
+    /**
+    * this does your basic RSA algorithm.
+    */
+    public class RsaEngine
+		: IAsymmetricBlockCipher
+    {
+		private RsaCoreEngine core;
+
+        public string AlgorithmName
+        {
+            get { return "RSA"; }
+        }
+
+		/**
+        * initialise the RSA engine.
+        *
+        * @param forEncryption true if we are encrypting, false otherwise.
+        * @param param the necessary RSA key parameters.
+        */
+        public void Init(
+            bool				forEncryption,
+            ICipherParameters	parameters)
+        {
+			if (core == null)
+				core = new RsaCoreEngine();
+
+			core.Init(forEncryption, parameters);
+		}
+
+		/**
+        * Return the maximum size for an input block to this engine.
+        * For RSA this is always one byte less than the key size on
+        * encryption, and the same length as the key size on decryption.
+        *
+        * @return maximum size for an input block.
+        */
+        public int GetInputBlockSize()
+        {
+			return core.GetInputBlockSize();
+        }
+
+		/**
+        * Return the maximum size for an output block to this engine.
+        * For RSA this is always one byte less than the key size on
+        * decryption, and the same length as the key size on encryption.
+        *
+        * @return maximum size for an output block.
+        */
+        public int GetOutputBlockSize()
+        {
+			return core.GetOutputBlockSize();
+        }
+
+		/**
+        * Process a single block using the basic RSA algorithm.
+        *
+        * @param inBuf the input array.
+        * @param inOff the offset into the input buffer where the data starts.
+        * @param inLen the length of the data to be processed.
+        * @return the result of the RSA process.
+        * @exception DataLengthException the input block is too large.
+        */
+        public byte[] ProcessBlock(
+            byte[]	inBuf,
+            int		inOff,
+            int		inLen)
+        {
+			if (core == null)
+				throw new InvalidOperationException("RSA engine not initialised");
+
+			return core.ConvertOutput(core.ProcessBlock(core.ConvertInput(inBuf, inOff, inLen)));
+        }
+    }
+}