/*
* 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.server.keyprovider;
import java.io.Closeable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import org.apache.sshd.common.keyprovider.AbstractKeyPairProvider;
import org.apache.sshd.common.util.SecurityUtils;
/**
* TODO Add javadoc
*
* @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
*/
public abstract class AbstractGeneratorHostKeyProvider extends AbstractKeyPairProvider {
private String path;
private String algorithm = "DSA";
private int keySize;
private KeyPair keyPair;
protected AbstractGeneratorHostKeyProvider() {
}
protected AbstractGeneratorHostKeyProvider(String path) {
this.path = path;
}
protected AbstractGeneratorHostKeyProvider(String path, String algorithm) {
this.path = path;
this.algorithm = algorithm;
}
protected AbstractGeneratorHostKeyProvider(String path, String algorithm, int keySize) {
this.path = path;
this.algorithm = algorithm;
this.keySize = keySize;
}
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
public String getAlgorithm() {
return algorithm;
}
public void setAlgorithm(String algorithm) {
this.algorithm = algorithm;
}
public int getKeySize() {
return keySize;
}
public void setKeySize(int keySize) {
this.keySize = keySize;
}
protected abstract KeyPair doReadKeyPair(InputStream is) throws Exception;
protected abstract void doWriteKeyPair(KeyPair kp, OutputStream os) throws Exception;
public synchronized KeyPair[] loadKeys() {
if (keyPair == null) {
if (path != null) {
File f = new File(path);
if (f.exists() && f.isFile()) {
keyPair = readKeyPair(f);
}
}
if (keyPair == null) {
keyPair = generateKeyPair(algorithm);
if (keyPair != null && path != null) {
writeKeyPair(keyPair, new File(path));
}
}
if (keyPair == null) {
return new KeyPair[0];
}
}
return new KeyPair[] { keyPair };
}
private KeyPair readKeyPair(File f) {
InputStream is = null;
try {
is = new FileInputStream(f);
return doReadKeyPair(is);
} catch (Exception e) {
log.warn("Unable to read key {}: {}", path, e);
} finally {
close(is);
}
return null;
}
private void writeKeyPair(KeyPair kp, File f) {
OutputStream os = null;
try {
os = new FileOutputStream(f);
doWriteKeyPair(kp, os);
} catch (Exception e) {
log.warn("Unable to write key {}: {}", path, e);
} finally {
close(os);
}
}
private KeyPair generateKeyPair(String algorithm) {
try {
KeyPairGenerator generator = SecurityUtils.getKeyPairGenerator(algorithm);
if (keySize != 0) {
generator.initialize(keySize);
}
log.info("Generating host key...");
KeyPair kp = generator.generateKeyPair();
return kp;
} catch (Exception e) {
log.warn("Unable to generate keypair", e);
return null;
}
}
private void close(Closeable c) {
try {
if (c != null) {
c.close();
}
} catch (IOException e) {
// Ignore
}
}
}