Package org.bouncycastle.crypto.engines

Class Grain128Engine

java.lang.Object

org.bouncycastle.crypto.engines.Grain128Engine

All Implemented Interfaces:

StreamCipher

public class Grain128Engine
extends Object
implements StreamCipher

Implementation of Martin Hell's, Thomas Johansson's and Willi Meier's stream cipher, Grain-128.

Constructor Summary

Constructors

Constructor	Description
Grain128Engine()

Method Summary

Modifier and Type	Method	Description
String	getAlgorithmName()	Return the name of the algorithm the cipher implements.
void	init(boolean forEncryption, CipherParameters params)	Initialize a Grain-128 cipher.
int	processBytes(byte[] in, int inOff, int len, byte[] out, int outOff)	process a block of bytes from in putting the result into out.
void	reset()	reset the cipher.
byte	returnByte(byte in)	encrypt/decrypt a single byte returning the result.

Methods inherited from class java.lang.Object

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

Constructor Details

Grain128Engine

public Grain128Engine()

Method Details

getAlgorithmName

public String getAlgorithmName()

Description copied from interface: StreamCipher

Return the name of the algorithm the cipher implements.

Specified by:

getAlgorithmName in interface StreamCipher

Returns:

the name of the algorithm the cipher implements.

init

public void init(boolean forEncryption,
 CipherParameters params)
          throws IllegalArgumentException

Initialize a Grain-128 cipher.

Specified by:

init in interface StreamCipher

Parameters:

forEncryption - Whether or not we are for encryption.

params - The parameters required to set up the cipher.

Throws:

IllegalArgumentException - If the params argument is inappropriate.

processBytes

public int processBytes(byte[] in,
 int inOff,
 int len,
 byte[] out,
 int outOff)
                 throws DataLengthException

Description copied from interface: StreamCipher

process a block of bytes from in putting the result into out.

Specified by:

processBytes in interface StreamCipher

Parameters:

in - the input byte array.

inOff - the offset into the in array where the data to be processed starts.

len - the number of bytes to be processed.

out - the output buffer the processed bytes go into.

outOff - the offset into the output byte array the processed data starts at.

Returns:

the number of bytes produced - should always be len.

Throws:

DataLengthException - if the output buffer is too small.

reset

public void reset()

Description copied from interface: StreamCipher

reset the cipher. This leaves it in the same state it was at after the last init (if there was one).

Specified by:

reset in interface StreamCipher

returnByte

public byte returnByte(byte in)

Description copied from interface: StreamCipher

encrypt/decrypt a single byte returning the result.

Specified by:

returnByte in interface StreamCipher

Parameters:

in - the byte to be processed.

Returns:

the result of processing the input byte.