Module ibm.crypto.hdwrcca

Package com.ibm.crypto.hdwrCCA.provider

Class DESedeKeyGenerator

java.lang.Object

javax.crypto.KeyGeneratorSpi

com.ibm.crypto.hdwrCCA.provider.DESedeKeyGenerator

public final class DESedeKeyGenerator
extends KeyGeneratorSpi

This class generates a secret key for use with the Triple DES algorithm.

This documentation describes a Service Provider Interface. It is provided for implementation insight only. This class is not intended to be called directly by application developers. Please consult the 'Java Cryptography Architecture Standard' for details on how to use this interface through a public standard class.

NOTE:

Certain operations may require specific hardware or software, or specific key types. See the rest of this document and the z/OS Unique Considerations Hardware Crypto Reference Guide for more details. Unsupported operations and/or combinations may result in a RuntimeException Hardware Error.

For public interface details, consult the JCE API documentation for javax.crypto.KeyGenerator.

Constructor Summary

Constructors

Constructor	Description
DESedeKeyGenerator()	Verify the JCE framework in the constructor.

Method Summary

Modifier and Type	Method	Description
protected SecretKey	engineGenerateKey()	Generates and returns a Triple DES key.
protected void	engineInit(int keysize, SecureRandom random)	Initializes this key generator for generating clear keys of a certain key size in bits, using the given source of randomness.
protected void	engineInit(SecureRandom random)	Initializes this key generator with a source of randomness.
protected void	engineInit(AlgorithmParameterSpec params, SecureRandom random)	Initializes this key generator with the specified parameter set and a user-provided source of randomness.

Methods inherited from class java.lang.Object

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

Constructor Details

DESedeKeyGenerator

public DESedeKeyGenerator()

Verify the JCE framework in the constructor.

Throws:

SecurityException - if fails to verify the JCE framework.

Method Details

engineInit

protected void engineInit(SecureRandom random)

Initializes this key generator with a source of randomness. It is not valid to specify a source of randomness for a key that will be generated as a secret hardware key.

Specified by:

engineInit in class KeyGeneratorSpi

Parameters:

random - the source of randomness for this generator

engineInit

protected void engineInit(AlgorithmParameterSpec params,
 SecureRandom random)
                   throws InvalidAlgorithmParameterException

Initializes this key generator with the specified parameter set and a user-provided source of randomness. If a CCAAlgorithmParameterSpec is specified, and the requested key type is either CCAAlgorithmParameterSpec.SECURE_INTERNAL_TOKEN or CCAAlgorithmParameterSpec.CKDS, then the DESede key will be generated as a secret hardware key. Key generation parameters are validated, these validations include

• Key size must be one of valid DESede key sizes.
• Hardware keys must use a supported key token wrapping mode.
• Hardware keys must have key usage of SymmetricKeyConstants.KeyUsage.OP_DATA, SymmetricKeyConstants.KeyUsage.OPEX_EXPORTER_IMPORTER, SymmetricKeyConstants.KeyUsage.OPEX_IMPORTER_EXPORTER, or null (default).
• A key encrypting key must be provided if generating a key encrypting key pair.

Specified by:

engineInit in class KeyGeneratorSpi

Parameters:

params - the key generation parameters, clear key will be generated if the parameter is null

random - the source of randomness for this key generator

Throws:

InvalidAlgorithmParameterException - if params is inappropriate for this key generator.

InvalidParameterException - if any of the key generation parameters fail validation.

RuntimeException - if the key wrapping mode specified by the key generation parameters is not supported by the current system.

engineInit

protected void engineInit(int keysize,
 SecureRandom random)

Initializes this key generator for generating clear keys of a certain key size in bits, using the given source of randomness.

Specified by:

engineInit in class KeyGeneratorSpi

Parameters:

keysize - the size of the key to generate. This is an algorithm independent method of initialization. For Triple DES keys, a keysize with 112 bits of entropy corresponds to a Triple DES key with 2 intermediate keys, and a keysize with 168 bits of entropy corresponds to a Triple DES key with 3 intermediate keys

random - the source of randomness for this key generator

Throws:

InvalidParameterException - if the specified key size is not valid.

engineGenerateKey

protected SecretKey engineGenerateKey()

Generates and returns a Triple DES key.

Specified by:

engineGenerateKey in class KeyGeneratorSpi

Returns:

the generated Triple DES secret key.