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 the RSASSA-PSS signature scheme, as defined in the PKCS#1 v2.2 standard.

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

RSASSA-PSS-params ::= SEQUENCE {
  hashAlgorithm      [0] HashAlgorithm      DEFAULT sha1,
  maskGenAlgorithm   [1] MaskGenAlgorithm   DEFAULT mgf1SHA1,
  saltLength         [2] INTEGER            DEFAULT 20,
  trailerField       [3] TrailerField       DEFAULT trailerFieldBC(1)
}

where

HashAlgorithm ::= AlgorithmIdentifier {
  {OAEP-PSSDigestAlgorithms}
}
MaskGenAlgorithm ::= AlgorithmIdentifier { {PKCS1MGFAlgorithms} }
TrailerField ::= INTEGER { trailerFieldBC(1) }

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 }|
  { OID id-sha512-224 PARAMETERS NULL }|
  { OID id-sha512-256 PARAMETERS NULL },
  ...  -- Allows for future expansion --
}
PKCS1MGFAlgorithms    ALGORITHM-IDENTIFIER ::= {
  { OID id-mgf1 PARAMETERS HashAlgorithm },
  ...  -- Allows for future expansion --
}

Since:

1.4

External Specifications

• RFC 8017: PKCS #1: RSA Cryptography Specifications Version 2.2

See Also:

• MGF1ParameterSpec
• AlgorithmParameterSpec
• Signature

Field Summary

Fields

Modifier and Type	Field	Description
static final PSSParameterSpec	DEFAULT	Deprecated. This field uses the default values defined in the PKCS #1 standard.
static final int	TRAILER_FIELD_BC	The TrailerFieldBC constant as defined in the PKCS #1 standard.

Constructor Summary

Constructors

Constructor	Description
PSSParameterSpec(int saltLen)	Deprecated. This constructor uses the default values defined in the PKCS #1 standard except for the salt length.
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

Modifier and Type	Method	Description
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 bytes.
int	getTrailerField()	Returns the value for the trailer field.

Methods declared in class Object

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

Modifier and Type	Method	Description
protected Object	clone()	Creates and returns a copy of this object.
boolean	equals(Object obj)	Indicates whether some other object is "equal to" this one.
protected void	finalize()	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
final Class<?>	getClass()	Returns the runtime class of this Object.
int	hashCode()	Returns a hash code value for this object.
final void	notify()	Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll()	Wakes up all threads that are waiting on this object's monitor.
String	toString()	Returns a string representation of the object.
final void	wait()	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
final void	wait(long timeoutMillis)	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
final void	wait(long timeoutMillis, int nanos)	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Field Details

TRAILER_FIELD_BC

public static final int TRAILER_FIELD_BC

The TrailerFieldBC constant as defined in the PKCS #1 standard.

Since:

11

See Also:

• Constant Field Values

DEFAULT

@Deprecated(since="19")
public static final PSSParameterSpec DEFAULT

Deprecated.

This field uses the default values defined in the PKCS #1 standard. Some of these defaults are no longer recommended due to advances in cryptanalysis -- see the PKCS#1 v2.2 standard for more details. Thus, it is recommended to create a new PSSParameterSpec with the desired parameter values using the PSSParameterSpec(String, String, AlgorithmParameterSpec, int, int) constructor.

The PSS parameter set with all default values.

Since:

1.5

External Specifications

• RFC 8017: PKCS #1: RSA Cryptography Specifications Version 2.2

Constructor Details

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. See the PSSParameterSpec section of the Java Security Standard Algorithm Names Specification for information about standard names for the hash function.

mgfName - the algorithm name of the mask generation function. See the PSSParameterSpec section of the Java Security Standard Algorithm Names Specification for information about standard names for 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 in bytes

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

External Specifications

• Java Security Standard Algorithm Names

PSSParameterSpec

@Deprecated(since="19")
public PSSParameterSpec(int saltLen)

Deprecated.

This constructor uses the default values defined in the PKCS #1 standard except for the salt length. Some of these defaults are no longer recommended due to advances in cryptanalysis -- see the PKCS#1 v2.2 standard for more details. Thus, it is recommended to explicitly specify all desired parameter values with the PSSParameterSpec(String, String, AlgorithmParameterSpec, int, int) constructor.

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

Parameters:

saltLen - the length of salt in bytes

Throws:

IllegalArgumentException - if saltLen is less than 0

External Specifications

• RFC 8017: PKCS #1: RSA Cryptography Specifications Version 2.2

Method Details

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 bytes.

Returns:

the salt length

getTrailerField

public int getTrailerField()

Returns the value for the trailer field.

Returns:

the value for the trailer field

Since:

1.5