org.bouncycastle.crypto.engines

Class AESEngine

Implemented Interfaces:
BlockCipher

public class AESEngine
extends java.lang.Object
implements BlockCipher

an implementation of the AES (Rijndael), from FIPS-197.

For further details see: http://csrc.nist.gov/encryption/aes/. This implementation is based on optimizations from Dr. Brian Gladman's paper and C code at http://fp.gladman.plus.com/cryptography_technology/rijndael/ There are three levels of tradeoff of speed vs memory Because java has no preprocessor, they are written as three separate classes from which to choose The fastest uses 8Kbytes of static tables to precompute round calculations, 4 256 word tables for encryption and 4 for decryption. The middle performance version uses only one 256 word table for each, for a total of 2Kbytes, adding 12 rotate operations per round to compute the values contained in the other tables from the contents of the first. The slowest version uses no static tables at all and computes the values in each round.

This file contains the middle performance version with 2Kbytes of static tables for round precomputation.

Constructor Summary

AESEngine()
default constructor - 128 bit block size.

Method Summary

String
getAlgorithmName()
int
getBlockSize()
void
init(boolean forEncryption, CipherParameters params)
initialise an AES cipher.
int
processBlock(byte[] in, int inOff, byte[] out, int outOff)
void
reset()

Constructor Details

AESEngine

public AESEngine()
default constructor - 128 bit block size.

Method Details

getAlgorithmName

public String getAlgorithmName()
Specified by:
getAlgorithmName in interface BlockCipher

getBlockSize

public int getBlockSize()
Specified by:
getBlockSize in interface BlockCipher

init

public void init(boolean forEncryption,
                 CipherParameters params)
initialise an AES cipher.
Specified by:
init in interface BlockCipher
Parameters:
forEncryption - whether or not we are for encryption.
params - the parameters required to set up the cipher.

processBlock

public int processBlock(byte[] in,
                        int inOff,
                        byte[] out,
                        int outOff)
Specified by:
processBlock in interface BlockCipher

reset

public void reset()
Specified by:
reset in interface BlockCipher