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package javax.crypto.spec;

import java.math.BigInteger;
import java.security.spec.AlgorithmParameterSpec;
import java.security.spec.MGF1ParameterSpec;

This class specifies the set of parameters used with OAEP Padding, as defined in the PKCS#1 v2.2 standard. Its ASN.1 definition in PKCS#1 standard is described below:
RSAES-OAEP-params ::= SEQUENCE {
  hashAlgorithm      [0] HashAlgorithm     DEFAULT sha1,
  maskGenAlgorithm   [1] MaskGenAlgorithm  DEFAULT mgf1SHA1,
  pSourceAlgorithm   [2] PSourceAlgorithm  DEFAULT pSpecifiedEmpty
}
where
HashAlgorithm ::= AlgorithmIdentifier {
  {OAEP-PSSDigestAlgorithms}
}
MaskGenAlgorithm ::= AlgorithmIdentifier { {PKCS1MGFAlgorithms} }
PSourceAlgorithm ::= AlgorithmIdentifier {
  {PKCS1PSourceAlgorithms}
}
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 --
}
PKCS1PSourceAlgorithms    ALGORITHM-IDENTIFIER ::= {
  { OID id-pSpecified PARAMETERS EncodingParameters },
  ...  -- Allows for future expansion --
}
EncodingParameters ::= OCTET STRING(SIZE(0..MAX))

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
Author:Valerie Peng
See Also:
Since:1.5
/** * This class specifies the set of parameters used with OAEP Padding, * as defined in the * <a href="https://tools.ietf.org/rfc/rfc8017.txt">PKCS#1 v2.2</a> standard. * * Its ASN.1 definition in PKCS#1 standard is described below: * <pre> * RSAES-OAEP-params ::= SEQUENCE { * hashAlgorithm [0] HashAlgorithm DEFAULT sha1, * maskGenAlgorithm [1] MaskGenAlgorithm DEFAULT mgf1SHA1, * pSourceAlgorithm [2] PSourceAlgorithm DEFAULT pSpecifiedEmpty * } * </pre> * where * <pre> * HashAlgorithm ::= AlgorithmIdentifier { * {OAEP-PSSDigestAlgorithms} * } * MaskGenAlgorithm ::= AlgorithmIdentifier { {PKCS1MGFAlgorithms} } * PSourceAlgorithm ::= AlgorithmIdentifier { * {PKCS1PSourceAlgorithms} * } * * 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 -- * } * PKCS1PSourceAlgorithms ALGORITHM-IDENTIFIER ::= { * { OID id-pSpecified PARAMETERS EncodingParameters }, * ... -- Allows for future expansion -- * } * EncodingParameters ::= OCTET STRING(SIZE(0..MAX)) * </pre> * <p>Note: the OAEPParameterSpec.DEFAULT uses the following: * <pre> * message digest -- "SHA-1" * mask generation function (mgf) -- "MGF1" * parameters for mgf -- MGF1ParameterSpec.SHA1 * source of encoding input -- PSource.PSpecified.DEFAULT * </pre> * * @see java.security.spec.MGF1ParameterSpec * @see PSource * * @author Valerie Peng * * @since 1.5 */
public class OAEPParameterSpec implements AlgorithmParameterSpec { private String mdName = "SHA-1"; private String mgfName = "MGF1"; private AlgorithmParameterSpec mgfSpec = MGF1ParameterSpec.SHA1; private PSource pSrc = PSource.PSpecified.DEFAULT;
The OAEP parameter set with all default values.
/** * The OAEP parameter set with all default values. */
public static final OAEPParameterSpec DEFAULT = new OAEPParameterSpec();
Constructs a parameter set for OAEP padding as defined in the PKCS #1 standard using the default values.
/** * Constructs a parameter set for OAEP padding as defined in * the PKCS #1 standard using the default values. */
private OAEPParameterSpec() { }
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.
Params:
  • 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:
/** * Constructs a parameter set for OAEP padding as defined in * the PKCS #1 standard using the specified message digest * algorithm <code>mdName</code>, mask generation function * algorithm <code>mgfName</code>, parameters for the mask * generation function <code>mgfSpec</code>, and source of * the encoding input P <code>pSrc</code>. * * @param mdName the algorithm name for the message digest. * @param mgfName the algorithm name for the mask generation * function. * @param mgfSpec the parameters for the mask generation function. * If null is specified, null will be returned by getMGFParameters(). * @param pSrc the source of the encoding input P. * @exception NullPointerException if <code>mdName</code>, * <code>mgfName</code>, or <code>pSrc</code> is null. */
public OAEPParameterSpec(String mdName, String mgfName, AlgorithmParameterSpec mgfSpec, PSource pSrc) { if (mdName == null) { throw new NullPointerException("digest algorithm is null"); } if (mgfName == null) { throw new NullPointerException("mask generation function " + "algorithm is null"); } if (pSrc == null) { throw new NullPointerException("source of the encoding input " + "is null"); } this.mdName = mdName; this.mgfName = mgfName; this.mgfSpec = mgfSpec; this.pSrc = pSrc; }
Returns the message digest algorithm name.
Returns:the message digest algorithm name.
/** * Returns the message digest algorithm name. * * @return the message digest algorithm name. */
public String getDigestAlgorithm() { return mdName; }
Returns the mask generation function algorithm name.
Returns:the mask generation function algorithm name.
/** * Returns the mask generation function algorithm name. * * @return the mask generation function algorithm name. */
public String getMGFAlgorithm() { return mgfName; }
Returns the parameters for the mask generation function.
Returns:the parameters for the mask generation function.
/** * Returns the parameters for the mask generation function. * * @return the parameters for the mask generation function. */
public AlgorithmParameterSpec getMGFParameters() { return mgfSpec; }
Returns the source of encoding input P.
Returns:the source of encoding input P.
/** * Returns the source of encoding input P. * * @return the source of encoding input P. */
public PSource getPSource() { return pSrc; } }