lightbulb_outline Please take our October 2018 developer survey. Start survey

PSSParameterSpec

public class PSSParameterSpec
extends Object implements AlgorithmParameterSpec

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


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-sha224 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

Summary

Fields

public static final PSSParameterSpec DEFAULT

The PSS parameter set with all default values.

Public constructors

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.

PSSParameterSpec(int saltLen)

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

Public methods

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.

Inherited methods

Fields

DEFAULT

added in API level 1
public static final PSSParameterSpec DEFAULT

The PSS parameter set with all default values.

Public constructors

PSSParameterSpec

added in API level 1
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 String: the algorithm name of the hash function.

mgfName String: the algorithm name of the mask generation function.

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

saltLen int: the length of salt.

trailerField int: the value of the trailer field.

Throws
NullPointerException if mdName, or mgfName is null.
IllegalArgumentException if saltLen or trailerField is less than 0.

PSSParameterSpec

added in API level 1
public PSSParameterSpec (int saltLen)

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

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

Throws
IllegalArgumentException if saltLen is less than 0.

Public methods

getDigestAlgorithm

added in API level 1
public String getDigestAlgorithm ()

Returns the message digest algorithm name.

Returns
String the message digest algorithm name.

getMGFAlgorithm

added in API level 1
public String getMGFAlgorithm ()

Returns the mask generation function algorithm name.

Returns
String the mask generation function algorithm name.

getMGFParameters

added in API level 1
public AlgorithmParameterSpec getMGFParameters ()

Returns the parameters for the mask generation function.

Returns
AlgorithmParameterSpec the parameters for the mask generation function.

getSaltLength

added in API level 1
public int getSaltLength ()

Returns the salt length in bits.

Returns
int the salt length.

getTrailerField

added in API level 1
public int getTrailerField ()

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

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