java.security.spec
Class PSSParameterSpec

java.lang.Object
  java.security.spec.PSSParameterSpec

All Implemented Interfaces:

AlgorithmParameterSpec

public class PSSParameterSpec
extends Object
implements AlgorithmParameterSpec

This class specifies a parameter spec for RSA-PSS signature scheme, as defined in the PKCS#1 v2.1 standard.

Its ASN.1 definition in PKCS#1 standard is described below:

 RSASSA-PSS-params ::= SEQUENCE {
   hashAlgorithm      [0] OAEP-PSSDigestAlgorithms  DEFAULT sha1,
   maskGenAlgorithm   [1] PKCS1MGFAlgorithms  DEFAULT mgf1SHA1,
   saltLength         [2] INTEGER  DEFAULT 20,
   trailerField       [3] INTEGER  DEFAULT 1
 }
 

where

 OAEP-PSSDigestAlgorithms    ALGORITHM-IDENTIFIER ::= {
   { OID id-sha1 PARAMETERS NULL   }|
   { OID id-sha256 PARAMETERS NULL }|
   { OID id-sha384 PARAMETERS NULL }|
   { OID id-sha512 PARAMETERS NULL },
   ...  -- Allows for future expansion --
 }

 PKCS1MGFAlgorithms    ALGORITHM-IDENTIFIER ::= {
   { OID id-mgf1 PARAMETERS OAEP-PSSDigestAlgorithms },
   ...  -- Allows for future expansion --
 }
 

Note: the PSSParameterSpec.DEFAULT uses the following: message digest -- "SHA-1" mask generation function (mgf) -- "MGF1" parameters for mgf -- MGF1ParameterSpec.SHA1 SaltLength -- 20 TrailerField -- 1

Since:

1.4

See Also:

MGF1ParameterSpec, AlgorithmParameterSpec, Signature

Field Summary

static PSSParameterSpec

DEFAULT The PSS parameter set with all default values.

Constructor Summary

PSSParameterSpec(int saltLen)
Creates a new PSSParameterSpec using the specified salt length and other default values as defined in PKCS#1.

PSSParameterSpec(String mdName, String mgfName, AlgorithmParameterSpec mgfSpec, int saltLen, int trailerField)
Creates a new PSSParameterSpec as defined in the PKCS #1 standard using the specified message digest, mask generation function, parameters for mask generation function, salt length, and trailer field values.

Method Summary

String	getDigestAlgorithm() Returns the message digest algorithm name.
String	getMGFAlgorithm() Returns the mask generation function algorithm name.
AlgorithmParameterSpec	getMGFParameters() Returns the parameters for the mask generation function.
int	getSaltLength() Returns the salt length in bits.
int	getTrailerField() Returns the value for the trailer field, i.e.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT

public static final PSSParameterSpec DEFAULT

The PSS parameter set with all default values.

Constructor Detail

PSSParameterSpec

public PSSParameterSpec(String mdName,
                        String mgfName,
                        AlgorithmParameterSpec mgfSpec,
                        int saltLen,
                        int trailerField)

Creates a new PSSParameterSpec as defined in the PKCS #1 standard using the specified message digest, mask generation function, parameters for mask generation function, salt length, and trailer field values.

Parameters:

mdName - the algorithm name of the hash function.

mgfName - the algorithm name of the mask generation function.

mgfSpec - the parameters for the mask generation function. If null is specified, null will be returned by getMGFParameters().

saltLen - the length of salt.

trailerField - the value of the trailer field.

Throws:

NullPointerException - if mdName, or mgfName is null.

IllegalArgumentException - if saltLen or trailerField is less than 0.

Since:

1.5

PSSParameterSpec

public PSSParameterSpec(int saltLen)

Creates a new PSSParameterSpec using the specified salt length and other default values as defined in PKCS#1.

Parameters:

saltLen - the length of salt in bits to be used in PKCS#1 PSS encoding.

Throws:

IllegalArgumentException - if saltLen is less than 0.

Method Detail

getDigestAlgorithm

public String getDigestAlgorithm()

Returns the message digest algorithm name.

Returns:

the message digest algorithm name.

Since:

1.5

getMGFAlgorithm

public String getMGFAlgorithm()

Returns the mask generation function algorithm name.

Returns:

the mask generation function algorithm name.

Since:

1.5

getMGFParameters

public AlgorithmParameterSpec getMGFParameters()

Returns the parameters for the mask generation function.

Returns:

the parameters for the mask generation function.

Since:

1.5

getSaltLength

public int getSaltLength()

Returns the salt length in bits.

Returns:

the salt length.

getTrailerField

public int getTrailerField()

Returns the value for the trailer field, i.e. bc in PKCS#1 v2.1.

Returns:

the value for the trailer field, i.e. bc in PKCS#1 v2.1.

Since:

1.5