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 * regarding copyright ownership.  The ASF licenses this file   *
 * to you under the Apache License, Version 2.0 (the            *
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 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
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 * under the License.                                           *
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package org.apache.james.protocols.netty;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;

import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.handler.execution.ExecutionHandler;
import org.jboss.netty.handler.ssl.SslHandler;
import org.jboss.netty.util.HashedWheelTimer;

/**
 * Abstract base class for {@link ChannelPipeline} implementations which use TLS 
 * 
 *
 */
public abstract class AbstractSSLAwareChannelPipelineFactory extends AbstractChannelPipelineFactory {

    
    private String[] enabledCipherSuites = null;

    public AbstractSSLAwareChannelPipelineFactory(int timeout,
                                                  int maxConnections, int maxConnectsPerIp, ChannelGroup group, ExecutionHandler eHandler,
                                                  ChannelHandlerFactory frameHandlerFactory, HashedWheelTimer hashedWheelTimer) {
        super(timeout, maxConnections, maxConnectsPerIp, group, eHandler, frameHandlerFactory, hashedWheelTimer);
    }

    public AbstractSSLAwareChannelPipelineFactory(int timeout,
            int maxConnections, int maxConnectsPerIp, ChannelGroup group, String[] enabledCipherSuites, ExecutionHandler eHandler,
            ChannelHandlerFactory frameHandlerFactory, HashedWheelTimer hashedWheelTimer) {
        this(timeout, maxConnections, maxConnectsPerIp, group, eHandler, frameHandlerFactory, hashedWheelTimer);
        
        // We need to copy the String array becuase of possible security issues.
        // See https://issues.apache.org/jira/browse/PROTOCOLS-18
        if (enabledCipherSuites != null) {
            this.enabledCipherSuites = new String[enabledCipherSuites.length];
            for (int i = 0; i < enabledCipherSuites.length; i++) {
                this.enabledCipherSuites[i] = new String(enabledCipherSuites[i]);
            }
        }
    }

    
    @Override
    public ChannelPipeline getPipeline() throws Exception {
        ChannelPipeline pipeline =  super.getPipeline();

        if (isSSLSocket()) {
            // We need to set clientMode to false.
            // See https://issues.apache.org/jira/browse/JAMES-1025
            SSLEngine engine = getSSLContext().createSSLEngine();
            engine.setUseClientMode(false);
            if (enabledCipherSuites != null && enabledCipherSuites.length > 0) {
                engine.setEnabledCipherSuites(enabledCipherSuites);
            }
            pipeline.addFirst(HandlerConstants.SSL_HANDLER, new SslHandler(engine));
        }
        return pipeline;
    }

    /**
     * Return if the socket is using SSL/TLS
     * 
     * @return isSSL
     */
    protected abstract boolean isSSLSocket();
    
    /**
     * Return the SSL context
     * 
     * @return context
     */
    protected abstract SSLContext getSSLContext();
}
