/*
 * 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.catalina.tribes.membership.cloud;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;

import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.net.jsse.PEMFile;

/**
 * Provider for SSL socket factory using certificate streams.
 */
public class CertificateStreamProvider extends AbstractStreamProvider {

    private static final Log log = LogFactory.getLog(CertificateStreamProvider.class);

    private final SSLSocketFactory factory;

    CertificateStreamProvider(String clientCertFile, String clientKeyFile, String clientKeyPassword,
            String clientKeyAlgo, String caCertFile) throws Exception {
        char[] password = (clientKeyPassword != null) ? clientKeyPassword.toCharArray() : new char[0];
        KeyManager[] keyManagers = configureClientCert(clientCertFile, clientKeyFile, password, clientKeyAlgo);
        TrustManager[] trustManagers = configureCaCert(caCertFile);
        SSLContext context = SSLContext.getInstance("TLS");
        context.init(keyManagers, trustManagers, null);
        factory = context.getSocketFactory();
    }

    @Override
    protected SSLSocketFactory getSocketFactory() {
        return factory;
    }

    private static KeyManager[] configureClientCert(String clientCertFile, String clientKeyFile,
            char[] clientKeyPassword, String clientKeyAlgo) throws Exception {
        try (InputStream certInputStream = new FileInputStream(clientCertFile)) {
            CertificateFactory certFactory = CertificateFactory.getInstance("X509");
            X509Certificate cert = (X509Certificate) certFactory.generateCertificate(certInputStream);

            PEMFile pemFile = new PEMFile(clientKeyFile, new String(clientKeyPassword), clientKeyAlgo);
            PrivateKey privKey = pemFile.getPrivateKey();

            KeyStore keyStore = KeyStore.getInstance("JKS");
            keyStore.load(null, null);

            String alias = cert.getSubjectX500Principal().getName();
            keyStore.setKeyEntry(alias, privKey, clientKeyPassword, new Certificate[] { cert });

            KeyManagerFactory keyManagerFactory =
                    KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
            keyManagerFactory.init(keyStore, clientKeyPassword);

            return keyManagerFactory.getKeyManagers();
        } catch (IOException ioe) {
            log.error(sm.getString("certificateStream.clientCertError", clientCertFile, clientKeyFile));
            throw ioe;
        }
    }

}
