org.jose4j.jwe.kdf.ConcatKeyDerivationFunctionFactory Maven / Gradle / Ivy
/*
* Copyright 2012-2021 Brian Campbell
*
* Licensed 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.jose4j.jwe.kdf;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class ConcatKeyDerivationFunctionFactory
{
private final static Logger log = LoggerFactory.getLogger(ConcatKeyDerivationFunctionFactory.class);
private static Class customKdfClass;
static
{
String name = System.getProperty("org.jose4j.jwe.kdf.ConcatenationKeyDerivationFunctionWithSha256");
if (name != null)
{
try
{
customKdfClass = (Class)Class.forName(name);
ConcatenationKeyDerivationFunctionWithSha256 kdf = customKdfClass.newInstance();
byte[] z = new byte[] {124, -81, 43, 14, -71, -72, -84, 75, 115, 73, -52, -39, 74, -58, 77, -83};
kdf.kdf(z, 512, new byte[8]);
log.debug("Using custom ConcatenationKeyDerivationFunctionWithSha256 implementation: " + kdf.getClass());
}
catch (Throwable e)
{
customKdfClass = null;
log.debug("Using jose4j's concatenation key derivation function implementation because of problems with " + name, e);
}
}
}
static ConcatenationKeyDerivationFunctionWithSha256 make(String provider)
{
if (customKdfClass != null)
{
try
{
return customKdfClass.newInstance();
}
catch (Exception e)
{
log.debug("Unable to create new instance of " + customKdfClass, e);
}
}
return new ConcatKeyDerivationFunction("SHA-256", provider);
}
}