/*
 *  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.tomcat.util.net.jsse;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.SocketException;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import javax.net.ssl.HandshakeCompletedEvent;
import javax.net.ssl.HandshakeCompletedListener;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocket;


/* JSSESupport

   Concrete implementation class for JSSE
   Support classes.

   This will only work with JDK 1.2 and up since it
   depends on JDK 1.2's certificate support

   @author EKR
   @author Craig R. McClanahan
   Parts cribbed from JSSECertCompat       
   Parts cribbed from CertificatesValve
*/

class JSSE14Support extends JSSESupport {

    private static org.apache.commons.logging.Log logger =
        org.apache.commons.logging.LogFactory.getLog(JSSE14Support.class);

    Listener listener = new Listener();

    public JSSE14Support(SSLSocket sock){
        super(sock);
        sock.addHandshakeCompletedListener(listener);
    }

    protected void handShake() throws IOException {
        if( ssl.getWantClientAuth() ) {
            logger.debug("No client cert sent for want");
        } else {
            ssl.setNeedClientAuth(true);
        }
        synchronousHandshake(ssl);
    }

    /**
     * JSSE in JDK 1.4 has an issue/feature that requires us to do a
     * read() to get the client-cert.  As suggested by Andreas
     * Sterbenz
     */
    private  void synchronousHandshake(SSLSocket socket) 
        throws IOException {
        InputStream in = socket.getInputStream();
        int oldTimeout = socket.getSoTimeout();
        socket.setSoTimeout(1000);
        byte[] b = new byte[0];
        listener.reset();
        socket.startHandshake();
        int maxTries = 60; // 60 * 1000 = example 1 minute time out
        for (int i = 0; i < maxTries; i++) {
	    if(logger.isTraceEnabled())
		logger.trace("Reading for try #" +i);
            try {
                int x = in.read(b);
            } catch(SSLException sslex) {
                logger.info("SSL Error getting client Certs",sslex);
                throw sslex;
            } catch (IOException e) {
                // ignore - presumably the timeout
            }
            if (listener.completed) {
                break;
            }
        }
        socket.setSoTimeout(oldTimeout);
        if (listener.completed == false) {
            throw new SocketException("SSL Cert handshake timeout");
        }
    }

    /** Return the X509certificates or null if we can't get them.
     *  XXX We should allow unverified certificates 
     */ 
    protected X509Certificate [] getX509Certificates(SSLSession session) 
	throws IOException 
    {
        Certificate [] certs=null;
        try {
	    certs = session.getPeerCertificates();
        } catch( Throwable t ) {
            logger.debug("Error getting client certs",t);
            return null;
        }
        if( certs==null ) return null;
        
        X509Certificate [] x509Certs = new X509Certificate[certs.length];
	for(int i=0; i < certs.length; i++) {
	    if( certs[i] instanceof X509Certificate ) {
		// always currently true with the JSSE 1.1.x
		x509Certs[i] = (X509Certificate)certs[i];
	    } else {
		try {
		    byte [] buffer = certs[i].getEncoded();
		    CertificateFactory cf =
			CertificateFactory.getInstance("X.509");
		    ByteArrayInputStream stream =
			new ByteArrayInputStream(buffer);
		    x509Certs[i] = (X509Certificate)
			cf.generateCertificate(stream);
		} catch(Exception ex) { 
		    logger.info("Error translating cert " + certs[i], ex);
		    return null;
		}
	    }
	    if(logger.isTraceEnabled())
		logger.trace("Cert #" + i + " = " + x509Certs[i]);
	}
	if(x509Certs.length < 1)
	    return null;
	return x509Certs;
    }


    private static class Listener implements HandshakeCompletedListener {
        volatile boolean completed = false;
        public void handshakeCompleted(HandshakeCompletedEvent event) {
            completed = true;
        }
        void reset() {
            completed = false;
        }
    }

}