org.apache.wss4j.common.derivedKey.DerivedKeyUtils Maven / Gradle / Ivy
/**
* 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 org.apache.wss4j.common.derivedKey;
import java.io.UnsupportedEncodingException;
import org.apache.wss4j.common.ext.WSSecurityException;
public final class DerivedKeyUtils {
private DerivedKeyUtils() {
// complete
}
/**
* Derive a key from this DerivedKeyToken instance
*
* @param length
* @param secret
* @throws org.apache.wss4j.stax.wss.ext.WSSecurityException
*
*/
public static byte[] deriveKey(String algorithm, String label, int length, byte[] secret, byte[] nonce, int offset)
throws WSSecurityException {
DerivationAlgorithm algo = AlgoFactory.getInstance(algorithm);
byte[] labelBytes;
try {
if (label == null || label.length() == 0) {
String defaultLabel = ConversationConstants.DEFAULT_LABEL + ConversationConstants.DEFAULT_LABEL;
labelBytes = defaultLabel.getBytes("UTF-8");
} else {
labelBytes = label.getBytes("UTF-8");
}
} catch (UnsupportedEncodingException ex) {
throw new WSSecurityException(WSSecurityException.ErrorCode.FAILURE, ex);
}
byte[] seed = new byte[labelBytes.length + nonce.length];
System.arraycopy(labelBytes, 0, seed, 0, labelBytes.length);
System.arraycopy(nonce, 0, seed, labelBytes.length, nonce.length);
long keyLength = length;
if (keyLength <= 0) {
keyLength = 32L;
}
return algo.createKey(secret, seed, offset, keyLength);
}
}