net.sf.mmm.crypto.symmetric.key.spec

Class SymmetricKeySpecFactoryImplPbe

java.lang.Object

net.sf.mmm.crypto.symmetric.key.spec.SymmetricKeySpecFactoryImplPbe

All Implemented Interfaces:

SymmetricKeySpecFactory

public class SymmetricKeySpecFactoryImplPbe
extends Object
implements SymmetricKeySpecFactory

Implementation of SymmetricKeySpecFactory for PBE (PBEKeySpec). For sufficient security strength you should use a salt of 20 bytes, a key length of 256 bits (never use less than 128 bits) and a high number of iterations (e.g. 65536).

Since:

1.0.0

Author:

Joerg Hohwiller (hohwille at users.sourceforge.net)

Field Summary

Fields

Modifier and Type	Field and Description
private int	iterationCount
private int	keyLength
private byte[]	salt

Constructor Summary

Constructors

Constructor and Description
SymmetricKeySpecFactoryImplPbe() The constructor.
SymmetricKeySpecFactoryImplPbe(byte[] salt) The constructor.
SymmetricKeySpecFactoryImplPbe(byte[] salt, int iterationCount) The constructor.
SymmetricKeySpecFactoryImplPbe(byte[] salt, int iterationCount, int keyLength) The constructor.

Method Summary

Modifier and Type	Method and Description
KeySpec	createKeySpec(String password)
int	getIterationCount()
int	getKeyLength()

Methods inherited from class java.lang.Object

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

Field Detail

salt

private byte[] salt

iterationCount

private int iterationCount

keyLength

private int keyLength

Constructor Detail

SymmetricKeySpecFactoryImplPbe

public SymmetricKeySpecFactoryImplPbe()

The constructor.

SymmetricKeySpecFactoryImplPbe

public SymmetricKeySpecFactoryImplPbe(byte[] salt)

The constructor.

Parameters:

salt - the salt or null for no salting.

SymmetricKeySpecFactoryImplPbe

public SymmetricKeySpecFactoryImplPbe(byte[] salt,
                                      int iterationCount)

The constructor.

Parameters:

salt - the salt or null for no salting.

iterationCount - the iteration count.

SymmetricKeySpecFactoryImplPbe

public SymmetricKeySpecFactoryImplPbe(byte[] salt,
                                      int iterationCount,
                                      int keyLength)

The constructor.

Parameters:

salt - the salt or null for no salting.

iterationCount - the iteration count.

keyLength - the key length.

Method Detail

createKeySpec

public KeySpec createKeySpec(String password)

Specified by:

createKeySpec in interface SymmetricKeySpecFactory

Parameters:

password - the secret password.

Returns:

the KeySpec for the given password. May contain additional information like salt.

getIterationCount

public int getIterationCount()

Returns:

the iteration count or 0 for no iterations.

getKeyLength

public int getKeyLength()

Returns:

the key length in bits or 0 if unspecified (to use defaults).