OAEPParameterSpec

AI-generated Key Takeaways

• OAEPParameterSpec defines parameters for OAEP padding as specified in the PKCS #1 standard.

• It includes the message digest algorithm, mask generation function, parameters for the MGF, and source of encoding input.

• A default parameter set OAEPParameterSpec.DEFAULT is available with pre-defined values.

• You can customize the parameters using the constructor OAEPParameterSpec(String mdName, String mgfName, AlgorithmParameterSpec mgfSpec, PSource pSrc).

• Methods like getDigestAlgorithm(), getMGFAlgorithm(), getMGFParameters(), and getPSource() allow accessing individual parameter values.

public class OAEPParameterSpec extends Object
implements AlgorithmParameterSpec

This class specifies the set of parameters used with OAEP Padding, as defined in the PKCS #1 standard. Its ASN.1 definition in PKCS#1 standard is described below:

 RSAES-OAEP-params ::= SEQUENCE {
   hashAlgorithm      [0] OAEP-PSSDigestAlgorithms     DEFAULT sha1,
   maskGenAlgorithm   [1] PKCS1MGFAlgorithms  DEFAULT mgf1SHA1,
   pSourceAlgorithm   [2] PKCS1PSourceAlgorithms  DEFAULT pSpecifiedEmpty
 }
 

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 --
 }
 PKCS1PSourceAlgorithms    ALGORITHM-IDENTIFIER ::= {
   { OID id-pSpecified PARAMETERS OCTET STRING },
   ...  -- Allows for future expansion --
 }
 

Note: the OAEPParameterSpec.DEFAULT uses the following: message digest -- "SHA-1" mask generation function (mgf) -- "MGF1" parameters for mgf -- MGF1ParameterSpec.SHA1 source of encoding input -- PSource.PSpecified.DEFAULT

See Also

• MGF1ParameterSpec
• PSource

Field Summary

public static final OAEPParameterSpec

DEFAULT

The OAEP parameter set with all default values.

Public Constructor Summary

OAEPParameterSpec(String mdName, String mgfName, AlgorithmParameterSpec mgfSpec, PSource pSrc) Constructs a parameter set for OAEP padding as defined in the PKCS #1 standard using the specified message digest algorithm mdName, mask generation function algorithm mgfName, parameters for the mask generation function mgfSpec, and source of the encoding input P pSrc.

Public 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.
PSource	getPSource() Returns the source of encoding input P.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Fields

public static final OAEPParameterSpec DEFAULT

The OAEP parameter set with all default values.

Public Constructors

public OAEPParameterSpec (String mdName, String mgfName, AlgorithmParameterSpec mgfSpec, PSource pSrc)

Constructs a parameter set for OAEP padding as defined in the PKCS #1 standard using the specified message digest algorithm mdName, mask generation function algorithm mgfName, parameters for the mask generation function mgfSpec, and source of the encoding input P pSrc.

Parameters

mdName	the algorithm name for the message digest.
mgfName	the algorithm name for the mask generation function.
mgfSpec	the parameters for the mask generation function. If null is specified, null will be returned by getMGFParameters().
pSrc	the source of the encoding input P.

Throws

NullPointerException	if mdName, mgfName, or pSrc is null.

Public Methods

public String getDigestAlgorithm ()

Returns the message digest algorithm name.

Returns

• the message digest algorithm name.

public String getMGFAlgorithm ()

Returns the mask generation function algorithm name.

Returns

• the mask generation function algorithm name.

public AlgorithmParameterSpec getMGFParameters ()

Returns the parameters for the mask generation function.

Returns

• the parameters for the mask generation function.

public PSource getPSource ()

Returns the source of encoding input P.

Returns

• the source of encoding input P.