org.bouncycastle.crypto.engines
Class ChaChaEngine

java.lang.Object
  org.bouncycastle.crypto.engines.Salsa20Engine
      org.bouncycastle.crypto.engines.ChaChaEngine

All Implemented Interfaces:

StreamCipher

public class ChaChaEngine
extends Salsa20Engine

Implementation of Daniel J. Bernstein's ChaCha stream cipher.

Field Summary

Fields inherited from class org.bouncycastle.crypto.engines.Salsa20Engine

DEFAULT_ROUNDS, engineState, rounds, sigma, tau, x

Constructor Summary

ChaChaEngine()
Creates a 20 rounds ChaCha engine.

ChaChaEngine(int rounds)
Creates a ChaCha engine with a specific number of rounds.

Method Summary

protected void	advanceCounter()
static void	chachaCore(int rounds, int[] input, int[] x) ChacCha function
protected void	generateKeyStream(byte[] output)
java.lang.String	getAlgorithmName() Return the name of the algorithm the cipher implements.
protected void	resetCounter()
protected void	setKey(byte[] keyBytes, byte[] ivBytes)

Methods inherited from class org.bouncycastle.crypto.engines.Salsa20Engine

getNonceSize, init, processBytes, reset, returnByte, rotl, salsaCore

Methods inherited from class java.lang.Object

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

Constructor Detail

ChaChaEngine

public ChaChaEngine()

Creates a 20 rounds ChaCha engine.

ChaChaEngine

public ChaChaEngine(int rounds)

Creates a ChaCha engine with a specific number of rounds.

Parameters:

rounds - the number of rounds (must be an even number).

Method Detail

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from interface: StreamCipher

Return the name of the algorithm the cipher implements.

Specified by:

getAlgorithmName in interface StreamCipher

Overrides:

getAlgorithmName in class Salsa20Engine

Returns:

the name of the algorithm the cipher implements.

advanceCounter

protected void advanceCounter()

Overrides:

advanceCounter in class Salsa20Engine

resetCounter

protected void resetCounter()

Overrides:

resetCounter in class Salsa20Engine

setKey

protected void setKey(byte[] keyBytes,
                      byte[] ivBytes)

Overrides:

setKey in class Salsa20Engine

generateKeyStream

protected void generateKeyStream(byte[] output)

Overrides:

generateKeyStream in class Salsa20Engine

chachaCore

public static void chachaCore(int rounds,
                              int[] input,
                              int[] x)

ChacCha function

Parameters:

input - input data