java.security.spec.PSSParameterSpec Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.security.spec;
/**
* The parameter specification for the RSA-PSS Signature scheme.
*
* Defined in the PKCS #1 v2.1
* standard.
*/
public class PSSParameterSpec implements AlgorithmParameterSpec {
/**
* The default parameter specification. It specifies the following parameters:
*
* - message digest: {@code "SHA-1"}
* - mask generation function (mgf): {@code "MGF1"}
* - parameters for the mgf: {@link MGF1ParameterSpec#SHA1}
* - salt length: {@code 20}
* - trailer field: {@code -1}
*
*/
public static final PSSParameterSpec DEFAULT = new PSSParameterSpec(20);
// Message digest algorithm name
private final String mdName;
// Mask generation function algorithm name
private final String mgfName;
// Mask generation function parameters
private final AlgorithmParameterSpec mgfSpec;
// Trailer field value
private final int trailerField;
// Salt length in bits
private final int saltLen;
/**
* Creates a new {@code PSSParameterSpec} with the specified salt length
* and the default values.
*
* @param saltLen
* the salt length (in bits).
* @throws IllegalArgumentException
* if {@code saltLen} is negative.
*/
public PSSParameterSpec(int saltLen) {
if (saltLen < 0) {
throw new IllegalArgumentException("saltLen < 0");
}
this.saltLen = saltLen;
this.mdName = "SHA-1";
this.mgfName = "MGF1";
this.mgfSpec = MGF1ParameterSpec.SHA1;
this.trailerField = 1;
}
/**
* Creates a new {@code PSSParameterSpec} with the specified message digest
* name, mask generation function name, mask generation function parameters,
* salt length, and trailer field value.
*
* @param mdName
* the name of the message digest algorithm.
* @param mgfName
* the name of the mask generation function algorithm.
* @param mgfSpec
* the parameter for the mask generation function algorithm.
* @param saltLen
* the salt length (in bits).
* @param trailerField
* the trailer field value.
* @throws IllegalArgumentException
* if {@code saltLen} or {@code trailerField} is negative.
*/
public PSSParameterSpec(String mdName, String mgfName,
AlgorithmParameterSpec mgfSpec, int saltLen, int trailerField) {
if (mdName == null) {
throw new NullPointerException("mdName == null");
}
if (mgfName == null) {
throw new NullPointerException("mgfName == null");
}
if (saltLen < 0) {
throw new IllegalArgumentException("saltLen < 0");
}
if (trailerField < 0) {
throw new IllegalArgumentException("trailerField < 0");
}
this.mdName = mdName;
this.mgfName = mgfName;
this.mgfSpec = mgfSpec;
this.saltLen = saltLen;
this.trailerField = trailerField;
}
/**
* Returns the length of the salt (in bits).
*
* @return the length of the salt (in bits).
*/
public int getSaltLength() {
return saltLen;
}
/**
* Returns the name of the message digest algorithm.
*
* @return the name of the message digest algorithm.
*/
public String getDigestAlgorithm() {
return mdName;
}
/**
* Returns the name of the mask generation function algorithm.
*
* @return the name of the mask generation function algorithm.
*/
public String getMGFAlgorithm() {
return mgfName;
}
/**
* Returns the parameter for the mask generation function algorithm.
*
* @return the parameter for the mask generation function algorithm, or
* {@code null} if none specified.
*/
public AlgorithmParameterSpec getMGFParameters() {
return mgfSpec;
}
/**
* Returns the trailer field value.
*
* @return the trailer field value.
*/
public int getTrailerField() {
return trailerField;
}
}