iaik.pkcs.pkcs5

Class PBKDF2ParameterSpec

java.lang.Object

javax.crypto.spec.PBEParameterSpec

iaik.pkcs.pkcs5.PBKDF2ParameterSpec

All Implemented Interfaces:

java.lang.Cloneable, java.security.spec.AlgorithmParameterSpec

Direct Known Subclasses:

PBES2ParameterSpec

public class PBKDF2ParameterSpec
extends javax.crypto.spec.PBEParameterSpec
implements java.lang.Cloneable

This class represents a parameter specification for the PBKDF2 key derivation function according to the PKCS#5 v2.1.

PBKDF2 parameters specify salt value, iteration count, length of the to-be-derived key (optional), and (MAC based) pseudo random function (default: HMCA/SHA1) to be used by the PBKDF2 function for deriving a secret key from a password:

 PBKDF2-params ::= SEQUENCE {
   salt CHOICE {
     specified OCTET STRING,
     otherSource AlgorithmIdentifier {{PBKDF2-SaltSources}}
   },
   iterationCount INTEGER (1..MAX),
   keyLength INTEGER (1..MAX) OPTIONAL,
   prf AlgorithmIdentifier {{PBKDF2-PRFs}} DEFAULT
     algid-hmacWithSHA1 }
 

The PBKDF2-params ASN.1 definition allows to specify the salt value as OCTET STRING or otherSource algorithm id. However, this implementation does not support the otherSource alternative because until now it is not yet fully specified by PKCS#5 (version v2.1).

Version:

File Revision 11

Constructor Summary

Constructors

Constructor and Description
PBKDF2ParameterSpec(byte[] salt, int iterationCount, int derivedKeyLength) Creates a PBKDF2 parameter set for PBKDF2 key derivation.

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.Object	clone() Returns a clone of this PBKDF2ParameterSpec.
int	getDerivedKeyLength() Returns the length the derived key should have.
int	getIterationCount() Returns the iteration count.
AlgorithmID	getPrf() Gets the pseudo random function to be used.
byte[]	getSalt() Returns the salt.
void	setPrf(AlgorithmID prf) Sets the pseudo random function to be used.
java.lang.String	toString() Returns a String representation of this PBKDF2ParameterSpec object.

Methods inherited from class java.lang.Object

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

Constructor Detail

PBKDF2ParameterSpec

public PBKDF2ParameterSpec(byte[] salt,
                   int iterationCount,
                   int derivedKeyLength)

Creates a PBKDF2 parameter set for PBKDF2 key derivation. Note that the given salt will be cloned by this constructor.

Parameters:

salt - the salt

iterationCount - the iteration count

derivedKeyLength - the length the derived key should have

Throws:

java.lang.IllegalArgumentException - if salt is null, or iteration count or derived key length are < 1

Method Detail

setPrf

public void setPrf(AlgorithmID prf)

Sets the pseudo random function to be used.

Parameters:

prf - the pseudo random MAC function to be used

getPrf

public AlgorithmID getPrf()

Gets the pseudo random function to be used.

Returns:

the pseudo random MAC function to be used (default: HMAC/SHA1)

getIterationCount

public int getIterationCount()

Returns the iteration count.

Overrides:

getIterationCount in class javax.crypto.spec.PBEParameterSpec

Returns:

the iteration count, or 0 if no iteration count has been set

getDerivedKeyLength

public final int getDerivedKeyLength()

Returns the length the derived key should have.

Returns:

the length the derived key should have, or 0 if no key length has been set

getSalt

public final byte[] getSalt()

Returns the salt.

Overrides:

getSalt in class javax.crypto.spec.PBEParameterSpec

Returns:

the (cloned) salt value

clone

public java.lang.Object clone()

Returns a clone of this PBKDF2ParameterSpec.

Overrides:

clone in class java.lang.Object

Returns:

a clone of this PBKDF2ParameterSpec

toString

public java.lang.String toString()

Returns a String representation of this PBKDF2ParameterSpec object.

Overrides:

toString in class java.lang.Object

Returns:

a String representation of this PBKDF2ParameterSpec object