SaslServerCreationCallback.java

/*
 * Copyright 2011 the original author or authors.
 *
 * Licensed 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.springframework.remoting.avro.servers;

import org.apache.avro.ipc.Responder;
import org.apache.avro.ipc.SaslSocketServer;
import org.apache.avro.ipc.Server;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

import javax.security.auth.callback.CallbackHandler;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.util.HashMap;
import java.util.Map;

/**
 * <p/>
 * {@link org.springframework.remoting.avro.AvroExporter} that delegates to Avro's {@link org.apache.avro.ipc.SaslSocketServer},
 * which in turn implements SASL - the simple authentication and security layer.
 * <p/>
 * <P> See  http://en.wikipedia.org/wiki/Simple_Authentication_and_Security_Layer for details.
 *
 * @author Josh Long
 * @see org.springframework.remoting.avro.AvroExporter
 */
public class SaslServerCreationCallback implements ServerCreationCallback {

    private CallbackHandler callbackHandler;
    private String saslMechanism;
    private String saslProtocol;
    private String serverName;
    private Map<String, ?> saslProperties;

    public void setCallbackHandler(CallbackHandler callbackHandler) {
        this.callbackHandler = callbackHandler;
    }

    public void setSaslMechanism(String saslMechanism) {
        this.saslMechanism = saslMechanism;
    }

    public void setSaslProtocol(String saslProtocol) {
        this.saslProtocol = saslProtocol;
    }

    public void setServerName(String serverName) {
        this.serverName = serverName;
    }

    public void setSaslProperties(Map<String, ?> saslProperties) {
        this.saslProperties = saslProperties;
    }


    @Override
    public Server buildServer(InetSocketAddress address, Responder responder) throws Exception {
        try {
            boolean fullSasl = StringUtils.hasText(this.saslMechanism) || StringUtils.hasText(this.saslProtocol) ||
                                       StringUtils.hasText(serverName) || callbackHandler != null || saslProperties != null;
            SaslSocketServer saslSocketServer;
            if (fullSasl) {
                if (saslProperties == null) {
                    saslProperties = new HashMap<String, Object>();
                }
                saslSocketServer = new SaslSocketServer(responder, address, saslMechanism, saslProtocol, serverName, saslProperties, callbackHandler);
            } else {
                // default, anonymous SASL (nothing wrong with that!)
                saslSocketServer = new SaslSocketServer(responder, address);
            }
            Assert.notNull(saslSocketServer, "we experienced an error building the server");
            return saslSocketServer;
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}