de.flexiprovider.api
Class KeyDerivation

java.lang.Object
  |
  +--de.flexiprovider.api.KeyDerivation

Direct Known Subclasses:

KDF1, KDF2, PBKDF1, PBKDF1_PKCS12, PBKDF2, X963

public abstract class KeyDerivation

extends java.lang.Object

This class defines a key derivation function. All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a particular Key Derivation algorithm. A key derivation function is used to generate a longer or shorter secret key, with a second secret shared by both parties. The derived secret key may be used by other schemes which use different key length, to the normal secret keys.

Author:

Jochen Hechler, Marcus Stögbauer, Martin Döring

Constructor Summary

KeyDerivation()

Method Summary

abstract byte[]	deriveKey(int keySize) Start the derivation process and return the derived key.
abstract void	init(byte[] secret, AlgorithmParameterSpec params) Initialize this KDF with a secret and parameters.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyDerivation

public KeyDerivation()

Method Detail

init

public abstract void init(byte[] secret,
                          AlgorithmParameterSpec params)
                   throws InvalidKeyException,
                          InvalidAlgorithmParameterException

Initialize this KDF with a secret and parameters.

Parameters:

secret - the secret from which to derive the key

params - the parameters

Throws:

InvalidKeyException - if the secret is invalid.

InvalidAlgorithmParameterException - if the parameters are invalid.

deriveKey

public abstract byte[] deriveKey(int keySize)

Start the derivation process and return the derived key. If supported by the concrete implementation, the derived key will be of the specified length.

Parameters:

keySize - the desired length of the derived key

Returns:

the derived key with the specified length, or null if the key size is < 0.