/*
* 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.ftpserver.command;
import java.io.IOException;
import java.net.InetSocketAddress;
import org.apache.ftpserver.DataConnectionException;
import org.apache.ftpserver.ServerDataConnectionFactory;
import org.apache.ftpserver.ftplet.FtpReply;
import org.apache.ftpserver.ftplet.FtpRequest;
import org.apache.ftpserver.interfaces.FtpIoSession;
import org.apache.ftpserver.interfaces.FtpServerContext;
import org.apache.ftpserver.util.FtpReplyUtil;
/**
* The EPSV command requests that a server listen on a data port and
* wait for a connection. The EPSV command takes an optional argument.
* The response to this command includes only the TCP port number of the
* listening connection. The format of the response, however, is
* similar to the argument of the EPRT command. This allows the same
* parsing routines to be used for both commands. In addition, the
* format leaves a place holder for the network protocol and/or network
* address, which may be needed in the EPSV response in the future. The
* response code for entering passive mode using an extended address
* MUST be 229.
*/
public
class EPSV extends AbstractCommand {
/**
* Execute command.
*/
public void execute(final FtpIoSession session,
final FtpServerContext context,
final FtpRequest request) throws IOException {
// reset state variables
session.resetState();
// set data connection
ServerDataConnectionFactory dataCon = session.getDataConnection();
try {
InetSocketAddress dataConAddress = dataCon.initPassiveDataConnection();
// get connection info
int servPort = dataConAddress.getPort();
// send connection info to client
String portStr = "|||" + servPort + '|';
session.write(FtpReplyUtil.translate(session, request, context, 229, "EPSV", portStr));
} catch(DataConnectionException e) {
session.write(FtpReplyUtil.translate(session, request, context, FtpReply.REPLY_425_CANT_OPEN_DATA_CONNECTION, "EPSV", null));
return;
}
}
}