org.bouncycastle.crypto.engines
Class RSABlindedEngine

java.lang.Object
  org.bouncycastle.crypto.engines.RSABlindedEngine

All Implemented Interfaces:

AsymmetricBlockCipher

public class RSABlindedEngine
extends java.lang.Object
implements AsymmetricBlockCipher

this does your basic RSA algorithm with blinding

Field Summary

private RSACoreEngine	core
private RSAKeyParameters	key
private java.security.SecureRandom	random
private static java.math.BigInteger	ZERO

Constructor Summary

RSABlindedEngine()

Method Summary

private java.math.BigInteger	calculateR(java.math.BigInteger m)
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

Field Detail

ZERO

private static java.math.BigInteger ZERO

core

private RSACoreEngine core

key

private RSAKeyParameters key

random

private java.security.SecureRandom random

Constructor Detail

RSABlindedEngine

public RSABlindedEngine()

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.

calculateR

private java.math.BigInteger calculateR(java.math.BigInteger m)