/*
* 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.sshd.common.digest;
import java.security.MessageDigest;
import org.apache.sshd.common.Digest;
import org.apache.sshd.common.util.SecurityUtils;
/**
* Base class for Digest algorithms based on the JCE provider.
*
* @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
*/
public class BaseDigest implements Digest {
private final String algorithm;
private int bsize;
private MessageDigest md;
/**
* Create a new digest using the given algorithm and block size.
* The initialization and creation of the underlying {@link MessageDigest}
* object will be done in the {@link #init()} method.
*
* @param algorithm the JCE algorithm to use for this digest
* @param bsize the block size of this digest
*/
public BaseDigest(String algorithm, int bsize) {
this.algorithm = algorithm;
this.bsize = bsize;
}
public int getBlockSize() {
return bsize;
}
public void init() throws Exception {
this.md = SecurityUtils.getMessageDigest(algorithm);
}
public void update(byte[] foo, int start, int len) throws Exception {
md.update(foo, start, len);
}
public byte[] digest() throws Exception {
return md.digest();
}
}