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

Its ASN.1 definition in 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 --
 }

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 Details

    • TRAILER_FIELD_BC

      public static final int TRAILER_FIELD_BC
      The TrailerFieldBC constant as defined in PKCS#1
      Since:
      11
      See Also:
      Constant Field Values

    • DEFAULT

      public static final PSSParameterSpec DEFAULT
      The PSS parameter set with all default values
      Since:
      1.5

  • 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
      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 bytes to be used in PKCS#1 PSS encoding
      Throws:
      IllegalArgumentException - if saltLen is less than 0

  • 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