iaik.security.cipher

Class IvParameterGenerator

java.lang.Object

java.security.AlgorithmParameterGeneratorSpi

iaik.security.cipher.IvParameterGenerator

Direct Known Subclasses:

AESIvParameterGenerator, CamelliaIvParameterGenerator

public class IvParameterGenerator
extends java.security.AlgorithmParameterGeneratorSpi

This class implements an AlgorithmParameterGenerator to be used for generating an initialization vector as used by many cipher algorithms/mode.

Applications shall use "IV" or the desired algorithm name for obtaining an AlgorithmParameterGenerator for generating IV parameters in opaque representation:

 AlgorithmParameterGenerator.getInstance("IV")
 

Once the generator has been created, it may be properly initialized by one of the several init methods. If none explicit initialization is done, per default the iv length is set to 8 bytes. After initializing the generator (or relying on default settings), the required parameters actually are created by calling the generateParameters method.

Version:

File Revision 13

Constructor Summary

Constructors

Constructor and Description
IvParameterGenerator() The default constructor.
IvParameterGenerator(int ivLength) Creates a IvParameterGenerator for the given iv length.

Method Summary

Methods

Modifier and Type	Method and Description
protected java.security.AlgorithmParameters	engineGenerateParameters() Actually generates the required IV AlgorithmParameters.
protected void	engineInit(java.security.spec.AlgorithmParameterSpec param, java.security.SecureRandom random) Initializes this generator with iv-specific parameter generation values and some random seed.
protected void	engineInit(int ivLength, java.security.SecureRandom random) Initializes the parameter generator with given iv length.

Methods inherited from class java.lang.Object

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

Constructor Detail

IvParameterGenerator

public IvParameterGenerator()

The default constructor.

Only internally used for creating a IvParameterGenerator object. Applications shall use one of the AlgorithmParameterGenerator.getInstance factory methods for obtaining an AlgorithmParamterGenerator for generating iv parameters.

IvParameterGenerator

public IvParameterGenerator(int ivLength)

Creates a IvParameterGenerator for the given iv length.

Only internally used for creating a IvParameterGenerator object. Applications shall use one of the AlgorithmParameterGenerator.getInstance factory methods for obtaining an AlgorithmParamterGenerator for generating iv parameters.

Parameters:

ivLength - the length of the initialization vector (in bytes)

Method Detail

engineInit

protected void engineInit(int ivLength,
              java.security.SecureRandom random)

Initializes the parameter generator with given iv length.

Specified by:

engineInit in class java.security.AlgorithmParameterGeneratorSpi

Parameters:

ivLength - the length of the initialization vector

random - the random seed to be used by this generator.

engineInit

protected void engineInit(java.security.spec.AlgorithmParameterSpec param,
              java.security.SecureRandom random)
                   throws java.security.InvalidAlgorithmParameterException

Initializes this generator with iv-specific parameter generation values and some random seed.

From the given parameter specification (which has to be of type IvGenParameterSpec) the iv length is obtained for generating the algorithm parameters.

Applications shall call init(param_spec, random) for provider independently accessing this method.

Specified by:

engineInit in class java.security.AlgorithmParameterGeneratorSpi

Parameters:

param - an instance of IvGenParameterSpec

random - the random seed to be used by this generator.

Throws:

java.security.InvalidAlgorithmParameterException - if param is not an instance of IvGenParameterSpec

engineGenerateParameters

protected java.security.AlgorithmParameters engineGenerateParameters()

Actually generates the required IV AlgorithmParameters.

Applications shall call generatePrameters() for provider independently accessing this method.

Specified by:

engineGenerateParameters in class java.security.AlgorithmParameterGeneratorSpi

Returns:

the new created AlgorithmParameters