org.spongycastle.crypto.engines

Class IDEAEngine

java.lang.Object

org.spongycastle.crypto.engines.IDEAEngine

All Implemented Interfaces:

BlockCipher

public class IDEAEngine
extends java.lang.Object
implements BlockCipher

A class that provides a basic International Data Encryption Algorithm (IDEA) engine.

This implementation is based on the "HOWTO: INTERNATIONAL DATA ENCRYPTION ALGORITHM" implementation summary by Fauzan Mirza (F.U.Mirza@sheffield.ac.uk). (barring 1 typo at the end of the mulinv function!).

It can be found at ftp://ftp.funet.fi/pub/crypt/cryptography/symmetric/idea/

Note: This algorithm was patented in the USA, Japan and Europe. These patents expired in 2011/2012.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	BLOCK_SIZE

Constructor Summary

Constructors

Constructor and Description
IDEAEngine() standard constructor.

Method Summary

Modifier and Type	Method and Description
java.lang.String	getAlgorithmName() Return the name of the algorithm the cipher implements.
int	getBlockSize() Return the block size for this cipher (in bytes).
void	init(boolean forEncryption, CipherParameters params) initialise an IDEA cipher.
int	processBlock(byte[] in, int inOff, byte[] out, int outOff) Process one block of input from the array in and write it to the out array.
void	reset() Reset the cipher.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BLOCK_SIZE

protected static final int BLOCK_SIZE

See Also:

Constant Field Values

Constructor Detail

IDEAEngine

public IDEAEngine()

standard constructor.

Method Detail

init

public void init(boolean forEncryption,
                 CipherParameters params)

initialise an IDEA 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.

Throws:

java.lang.IllegalArgumentException - if the params argument is inappropriate.

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from interface: BlockCipher

Return the name of the algorithm the cipher implements.

Specified by:

getAlgorithmName in interface BlockCipher

Returns:

the name of the algorithm the cipher implements.

getBlockSize

public int getBlockSize()

Description copied from interface: BlockCipher

Return the block size for this cipher (in bytes).

Specified by:

getBlockSize in interface BlockCipher

Returns:

the block size for this cipher in bytes.

processBlock

public int processBlock(byte[] in,
                        int inOff,
                        byte[] out,
                        int outOff)

Description copied from interface: BlockCipher

Process one block of input from the array in and write it to the out array.

Specified by:

processBlock in interface BlockCipher

Parameters:

in - the array containing the input data.

inOff - offset into the in array the data starts at.

out - the array the output data will be copied into.

outOff - the offset into the out array the output will start at.

Returns:

the number of bytes processed and produced.

reset

public void reset()

Description copied from interface: BlockCipher

Reset the cipher. After resetting the cipher is in the same state as it was after the last init (if there was one).

Specified by:

reset in interface BlockCipher