org.gudy.bouncycastle.crypto.engines
Class RSAEngine

java.lang.Object
  extended by org.gudy.bouncycastle.crypto.engines.RSAEngine
All Implemented Interfaces:
AsymmetricBlockCipher

public class RSAEngine
extends Object
implements AsymmetricBlockCipher

this does your basic RSA algorithm.


Constructor Summary
RSAEngine()
           
 
Method Summary
 int getInputBlockSize()
          Return the maximum size for an input block to this engine.
 int getOutputBlockSize()
          Return the maximum size for an output block to this engine.
 void init(boolean forEncryption, CipherParameters param)
          initialise the RSA engine.
 byte[] processBlock(byte[] in, int inOff, int inLen)
          Process a single block using the basic RSA algorithm.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

RSAEngine

public RSAEngine()
Method Detail

init

public void init(boolean forEncryption,
                 CipherParameters param)
initialise the RSA engine.

Specified by:
init in interface AsymmetricBlockCipher
Parameters:
forEncryption - true if we are encrypting, false otherwise.
param - the necessary RSA key parameters.

getInputBlockSize

public int getInputBlockSize()
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.

Specified by:
getInputBlockSize in interface AsymmetricBlockCipher
Returns:
maximum size for an input block.

getOutputBlockSize

public int getOutputBlockSize()
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.

Specified by:
getOutputBlockSize in interface AsymmetricBlockCipher
Returns:
maximum size for an output block.

processBlock

public byte[] processBlock(byte[] in,
                           int inOff,
                           int inLen)
Process a single block using the basic RSA algorithm.

Specified by:
processBlock in interface AsymmetricBlockCipher
Parameters:
in - the input array.
inOff - the offset into the input buffer where the data starts.
inLen - the length of the data to be processed.
Returns:
the result of the RSA process.
Throws:
DataLengthException - the input block is too large.