iaik.pkcs.pkcs5

Class KeyFactory

java.lang.Object

javax.crypto.SecretKeyFactorySpi

iaik.pkcs.pkcs5.KeyFactory

public final class KeyFactory
extends javax.crypto.SecretKeyFactorySpi

SecretKeyFactory implementation for the PBE ciphers (PKCS#5).

Keys may appear in two representations within the Java Security environment:

• opaque, of type java.security.Key
• transparent, of some ...Spec type (specification, key material), e.g. DESKeySpec

This SecretKey factory may be used for converting opaque secret keys (instances of javax.crypto.SecretKey, iaik.security.cipher.PBEKey) into transparent PBE key material (instances of javax.crypto.spec.PBEKeySpec) according to the PKCS #5: Password-Based Cryptography Specification Version 2.0 (RFC 2898).

An application shall use the getInstance factory method of the javax.crypto.SecretKeyFactory engine class for accessing this PBE KeyFactory, e.g.:

 PBEKeySpec keySpec = new PBEKeySpec("password".toCharArray());
 SecretKeyFactory kf = SecretKeyFactory.getInstance("PBE", "IAIK");
 SecretKey sk = kf.generateSecret(keySpec);
 

Constructor Summary

Constructors

Constructor and Description
KeyFactory() Default constructor.

Method Summary

Modifier and Type	Method and Description
protected javax.crypto.SecretKey	engineGenerateSecret(java.security.spec.KeySpec keySpec) Converts the given key specification (key material) into a SecretKey object.
protected java.security.spec.KeySpec	engineGetKeySpec(javax.crypto.SecretKey secretKey, java.lang.Class classSpec) Converts the given secret key into the requested key specification (key material).
protected javax.crypto.SecretKey	engineTranslateKey(javax.crypto.SecretKey secretKey) Translates a key object of some unknown or untrusted provider into a secret key object of this key factory.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyFactory

public KeyFactory()

Default constructor.

Method Detail

engineGenerateSecret

protected javax.crypto.SecretKey engineGenerateSecret(java.security.spec.KeySpec keySpec)
                                               throws java.security.spec.InvalidKeySpecException

Converts the given key specification (key material) into a SecretKey object.

The supplied keySpec has to be an instance of javax.crypto.spec.PBEKeySpec.

Specified by:

engineGenerateSecret in class javax.crypto.SecretKeyFactorySpi

Parameters:

keySpec - the specification (key material) to be converted into SecretKey representation.

Returns:

the SecretKey object as instance of iaik.security.cipher.PBEKey

Throws:

java.security.spec.InvalidKeySpecException - if the given key material cannot be converted into a SecretKey object by this key factory

engineGetKeySpec

protected java.security.spec.KeySpec engineGetKeySpec(javax.crypto.SecretKey secretKey,
                                                      java.lang.Class classSpec)
                                               throws java.security.spec.InvalidKeySpecException

Converts the given secret key into the requested key specification (key material).

This method may be used for getting a javax.crypto.spec.PBEKeySpec from the given secret key. The supplied secret key has to be an instance of iaik.security.cipher.PBEKey.

Specified by:

engineGetKeySpec in class javax.crypto.SecretKeyFactorySpi

Parameters:

secretKey - the secret key to be converted

classSpec - the class implementing the requested secret key spec

Returns:

the key specification (key material) derived from the given secret key

Throws:

java.security.spec.InvalidKeySpecException - if the given secret key cannot be converted into the requested key specification object by this key factory

engineTranslateKey

protected javax.crypto.SecretKey engineTranslateKey(javax.crypto.SecretKey secretKey)
                                             throws java.security.InvalidKeyException

Translates a key object of some unknown or untrusted provider into a secret key object of this key factory.

Specified by:

engineTranslateKey in class javax.crypto.SecretKeyFactorySpi

Parameters:

secretKey - the key of some unknown or untrusted provider

Returns:

the translated key as instance of iaik.security.cipher.PBEKey

Throws:

java.security.InvalidKeyException - if the given key cannot be translated by this key factory