edu.vt.middleware.crypt.pbe
Class AbstractPKCSKeyGenerator

java.lang.Object
  edu.vt.middleware.crypt.pbe.AbstractPKCSKeyGenerator

All Implemented Interfaces:

KeyGenerator

Direct Known Subclasses:

PBKDF1KeyGenerator, PBKDF2KeyGenerator, PKCS12KeyGenerator

public abstract class AbstractPKCSKeyGenerator
extends Object
implements KeyGenerator

Base class for all PKCS key generators that use a key derivation function that performs iterative hashing operations on a salted password.

For a key derivation function f, the following formula applies:
derivedKey = f(password, salt, iterations)

Classes derived from this class are NOT thread safe.

Version:

$Revision: 2744 $

Author:

Middleware Services

Field Summary

static int	DEFAULT_ITERATION_COUNT Default number of iterations taken from examples in PKCS#5v2.
protected int	iterationCount Key derifcation function iteration count.
protected byte[]	salt Key derifcation function salt.

Constructor Summary

AbstractPKCSKeyGenerator()

Method Summary

byte[]	generate(char[] password, int size) Generates a symmetric key from a password for use in password-based encryption schemes.
protected abstract org.bouncycastle.crypto.PBEParametersGenerator	newParamGenerator() Creates a new BC parameter generator instance.
protected void	setIterationCount(int count) Gets the key derivation function iteration count.
protected abstract byte[]	toBytes(char[] password) Converts password characters to bytes in implementation-dependent fashion.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_ITERATION_COUNT

public static final int DEFAULT_ITERATION_COUNT

Default number of iterations taken from examples in PKCS#5v2.

See Also:

Constant Field Values

salt

protected byte[] salt

Key derifcation function salt.

iterationCount

protected int iterationCount

Key derifcation function iteration count.

Constructor Detail

AbstractPKCSKeyGenerator

public AbstractPKCSKeyGenerator()

Method Detail

generate

public byte[] generate(char[] password,
                       int size)

Generates a symmetric key from a password for use in password-based encryption schemes.

Specified by:

generate in interface KeyGenerator

Parameters:

password - Password used as basis for generated key.

size - Size of generated key in bits, unless otherwise noted.

Returns:

Secret key bytes.

setIterationCount

protected void setIterationCount(int count)

Gets the key derivation function iteration count.

Parameters:

count - Iteration count. MUST be positive integer.

newParamGenerator

protected abstract org.bouncycastle.crypto.PBEParametersGenerator newParamGenerator()

Creates a new BC parameter generator instance.

Returns:

New parameter generator.

toBytes

protected abstract byte[] toBytes(char[] password)

Converts password characters to bytes in implementation-dependent fashion.

Parameters:

password - Password to convert.

Returns:

Password bytes.