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)));
}
}
}
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