iaik.pkcs.pkcs5

Class PBES2ParameterSpec

java.lang.Object

javax.crypto.spec.PBEParameterSpec

iaik.pkcs.pkcs5.PBKDF2ParameterSpec

iaik.pkcs.pkcs5.PBES2ParameterSpec

All Implemented Interfaces:

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

public class PBES2ParameterSpec
extends PBKDF2ParameterSpec
implements java.lang.Cloneable

This class represents a parameter specification for the PBES2 password based encryption scheme according to the PKCS#5 v2.1 Password-Based Cryptography Standard.

PBES2 parameters specify parameters for deriving a secret key from a password, and the encryption scheme for encrypting the data with the derived secret key:

 PBES2-params ::= SEQUENCE {
   keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
   encryptionScheme AlgorithmIdentifier {{PBES2-Encs}} }
   
 PBES2-KDFs ALGORITHM-IDENTIFIER ::=
   { {PBKDF2-params IDENTIFIED BY id-PBKDF2}, ... }
   
 PBES2-Encs ALGORITHM-IDENTIFIER ::= { ... }
 

The default key derivation function used by PBES2 is PBKDF2 which uses the following parameters: salt value, iteration count, length of the to-be-derived key (optional), and (MAC based) pseudo random function (default: HMCA/SHA1):

 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
PBES2ParameterSpec(byte[] salt, int iterationCount, int derivedKeyLength, AlgorithmID encryptionScheme) Creates a PBES2 parameter set for PBES2 encryption.

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.Object	clone() Returns a clone of this PBES2ParameterSpec.
java.lang.String	getAlgorithm() Gets the algorithm name for this PBES2ParameterSpec.
AlgorithmID	getEncryptionScheme() Gets the encryption scheme to be used.
java.security.spec.AlgorithmParameterSpec	getEncryptionSchemeParameters() Gets the cipher parameters used by the encryption scheme, if included.
java.security.spec.AlgorithmParameterSpec	getParameterSpec() Gets the cipher parameters used by the encryption scheme, if included.
void	setEncryptionSchemeParameters(java.security.spec.AlgorithmParameterSpec paramSpec) Sets the cipher parameters used by the encryption scheme.
java.lang.String	toString() Returns a String representation of this PBES2ParameterSpec object.
java.lang.String	toString(boolean detailed) Returns a String representation of this PBES2ParameterSpec object.

Methods inherited from class iaik.pkcs.pkcs5.PBKDF2ParameterSpec

getDerivedKeyLength, getIterationCount, getPrf, getSalt, setPrf

Methods inherited from class java.lang.Object

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

Constructor Detail

PBES2ParameterSpec

public PBES2ParameterSpec(byte[] salt,
                  int iterationCount,
                  int derivedKeyLength,
                  AlgorithmID encryptionScheme)

Creates a PBES2 parameter set for PBES2 encryption. 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

encryptionScheme - the encryption scheme to be used

Throws:

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

Method Detail

getEncryptionScheme

public AlgorithmID getEncryptionScheme()

Gets the encryption scheme to be used.

Returns:

the encryption scheme to be used

getEncryptionSchemeParameters

public java.security.spec.AlgorithmParameterSpec getEncryptionSchemeParameters()
                                                                        throws java.security.InvalidAlgorithmParameterException

Gets the cipher parameters used by the encryption scheme, if included.

Returns:

the parameters contained in the encryption scheme AlgorithmID as AlgorithmParameterSpec (e.g. IvParameterSpec), or null if no parameters are included

Throws:

java.security.InvalidAlgorithmParameterException - if the parameters cannot be got

getParameterSpec

public java.security.spec.AlgorithmParameterSpec getParameterSpec()

Gets the cipher parameters used by the encryption scheme, if included.

This method simply calls getEncryptionSchemeParameters, this it might be better to immediately call method getEncryptionSchemeParameters.

Returns:

the parameters contained in the encryption scheme AlgorithmID as AlgorithmParameterSpec (e.g. IvParameterSpec), or null if no parameters are included

Throws:

java.security.InvalidAlgorithmParameterException - if the parameters cannot be got

See Also:

getEncryptionSchemeParameters

setEncryptionSchemeParameters

public void setEncryptionSchemeParameters(java.security.spec.AlgorithmParameterSpec paramSpec)
                                   throws java.security.InvalidAlgorithmParameterException

Sets the cipher parameters used by the encryption scheme.

Parameters:

paramSpec - the parameters to be used for the encryption scheme (e.g. an IvParameterSpec)

Throws:

java.security.InvalidAlgorithmParameterException - if an error occurs when getting the algorithm parameters

clone

public java.lang.Object clone()

Returns a clone of this PBES2ParameterSpec.

Overrides:

clone in class PBKDF2ParameterSpec

Returns:

a clone of this PBES2ParameterSpec

getAlgorithm

public java.lang.String getAlgorithm()

Gets the algorithm name for this PBES2ParameterSpec.

Returns:

the algorithm name

toString

public java.lang.String toString()

Returns a String representation of this PBES2ParameterSpec object.

Overrides:

toString in class PBKDF2ParameterSpec

Returns:

a String representation of this PBES2ParameterSpec object

toString

public java.lang.String toString(boolean detailed)

Returns a String representation of this PBES2ParameterSpec object.

Returns:

a String representation of this PBES2ParameterSpec object