sftp.java

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/*
 * Copyright (c) 2001 Sun Microsystems, Inc.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *       Sun Microsystems, Inc. for Project JXTA."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact Project JXTA at http://www.jxta.org.
 *
 * 5. Products derived from this software may not be called "JXTA",
 *    nor may "JXTA" appear in their name, without prior written
 *    permission of Sun.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL SUN MICROSYSTEMS OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Project JXTA.  For more
 * information on Project JXTA, please see
 * <http://www.jxta.org/>.
 *
 * This license is based on the BSD license adopted by the Apache Foundation.
 *
 * $Id: sftp.java,v 1.9 2004/06/02 19:59:29 bondolo Exp $
 */


package net.jxta.impl.shell.bin.sftp;

import net.jxta.impl.shell.*;

import java.io.*;
import java.util.*;

import net.jxta.exception.*;
import net.jxta.discovery.*;
import net.jxta.endpoint.*;
import net.jxta.pipe.*;
import net.jxta.impl.pipe.*;
import net.jxta.peergroup.*;
import net.jxta.document.*;
import net.jxta.id.*;
import net.jxta.protocol.*;

/**
 * fsend Shell command: send a file to a user.
 *
 */

public class sftp extends ShellApp implements Runnable {

    private DiscoveryService discovery=null;

    private ShellEnv env = null;
    private PipeAdvertisement userAdv = null;
    private static final int WaitingTime = 2000;
    private static final int  MAXRETRIES = 5;
    public static final String SftpNameTag = "JxtaSftpUserName";
    public static final String SftpIDTag = "JxtaSftpPipeID";
    private static final String EnvName = "sftpd";
    // local user
    private String userName = null;

    private static final String SenderName = "JxtaSftpSenderName";
    private static final String JftpData = "JxtaSftpData";
    private static final String FileInfo = "JxtaSftpInfo";
    private Thread thread = null;

    // Some file stuff
    private String fsep = "";
    private static final String fdirname = "sftp";
    private String fdir = null;

    public sftp() {
        // Set up a directory path for sftp repository
        try {
            fsep = System.getProperty("file.separator");
        } catch (Exception e) {
            ;
        } // should never happen

        fdir = fdirname + fsep;
        File f = new File(fdir);
        if (!f.exists()) {
            try {
                if (!f.mkdir()) {
                    // try "home" directory as root
                    fdir = "";
                }
            } catch (Exception ex) {
                fdir = null;
                println("Exception = " + ex.getMessage() +
                        "while creating new file " + fdir);
            }
        }
    }

    public void stopApp() {}

    private int syntaxError() {

        println("Usage: sftp -register userName");
        println("       sftp -login userName ");
        println("       sftp -logout userName ");
        println("       sftp -s userName destUserName filename");
        println("       sftp -search");

        return ShellApp.appParamError;
    }
    public int startApp(String[] args) {

        if ((args == null) || (args.length == 0)) {
            return syntaxError();
        }

        env = getEnv();
        discovery= getGroup().getDiscoveryService();

        if (args[0].equals("-register")) {
            return registerNewUser(args);
        }

        if (args[0].equals("-login")) {
            return login(args);
        }

        if (args[0].equals("-logout")) {
            return logout(args);
        }
        if (args[0].equals("-search")) {
            return findUsers();
        }

        return sendFile(args);
    }


    private boolean daemonRunning(String name) {

        ShellObject obj = env.get(EnvName + "." + name + "@" +
                                  (getGroup().getPeerGroupAdvertisement()).getName());
        if (obj == null) {
            return false;
        } else {
            return true;
        }
    }

    private int login(String[] args) {

        if (args.length != 2) {
            return syntaxError();
        }

        String name = args[1];
        if (daemonRunning(name)) {
            println("sftp: user " + name + " is already listening");
            return ShellApp.appMiscError;
        }

        PipeAdvertisement adv = findUserAdv(name);
        if (adv == null) {
            println("ftpd: " + name + " is not a registered user");
            return ShellApp.appMiscError;
        } else
            discovery.remotePublish(adv);

        runDaemon(name, adv);

        return ShellApp.appNoError;
    }



    private int findUsers() {

        Enumeration each;
        int i =0;



        discovery.getRemoteAdvertisements(null, DiscoveryService.ADV,
                                          PipeAdvertisement.NameTag,
                                          SftpNameTag +".*",
                                          20, null);

        while (true) {
            try {
                if (i > MAXRETRIES) {
                    println("");
                    break;
                }
                Thread.sleep(WaitingTime);
                print(".");
                i++;
            } catch (Exception e) {
                println("findUsers, exception = " + e.getMessage());
            }
        }

        try {

            each = discovery.getLocalAdvertisements(DiscoveryService.ADV,
                                                    PipeAdvertisement.NameTag,
                                                    SftpNameTag +".*");
            if ((each != null) && (each.hasMoreElements())) {
                PipeAdvertisement adv = null;
                println("found the following registrations:");
                while (each.hasMoreElements()) {

                    try {

                        adv = (PipeAdvertisement) each.nextElement();
                        println(adv.getName());

                    } catch(Exception e) {

                        println("findUsers, exception = " + e.getMessage());

                        continue;
                    }
                }
            }
        } catch (Exception e) {

            println("findUsers, exception = " + e.getMessage());

        }

        return ShellApp.appNoError;
    }

    private int logout(String[] args) {

        if (args.length != 2) {
            return syntaxError();
        }

        String name = args[1];
        if (!daemonRunning(name)) {
            println("ftpd: user " + name + " is not listening");
            return ShellApp.appMiscError;
        }
        stopDaemon(name);
        return ShellApp.appNoError;
    }

    // sftp -s <source pipe> <dest pipe> <filename>
    // is required
    private static final int OBUFLEN = 15000;

    private int sendFile(String[] args) {

        if (!args[0].equals("-s") || args.length != 4) {
            return syntaxError();
        }

        String srcName = args[1];
        String name = args[2];
        String fileName = args[3];

        // check if the srcName is registered
        if (!daemonRunning(srcName)) {

            println("sftpd: user " + srcName + " is not logged in");

            return ShellApp.appMiscError;
        }

        // Locate target name
        PipeAdvertisement adv = findUserAdv(name);
        if (adv == null) {
            println("sftp: " + name + " is not a registered user");
            return ShellApp.appMiscError;
        }

        // Try and connect to target
        OutputPipe pipeOut = null;
        try {
            println("found user's advertisement attempting to connect");
            pipeOut = getGroup().getPipeService().createOutputPipe(adv, 120000);
            println("Please be patient ...");
            if (pipeOut == null) {
                println("sftp:  user " + name + " is not listening. Try again later");
                return ShellApp.appMiscError;
            }
        } catch (Exception e) {
            println("sftp: user " + name + " is not listening. Try again later" +
                    "\n      Exception = " + e.getMessage());
            return ShellApp.appMiscError;
        }

        // Try and open the file
        File f = null;
        DataInputStream fs = null;
        try {
            f = new File(fileName);
            fs = new DataInputStream( new FileInputStream(f) );
        } catch (Exception e) {
            println("sftp: Could not open " +  fileName +
                    "\n      Exception = " + e.getMessage());
            pipeOut.close();
            return ShellApp.appMiscError;
        }


        // Get the user text
        long fileSize = f.length();

        // fileinfo message
        //  Strip any path info
        int pix = fileName.lastIndexOf(fsep);
        String stripped = null;
        if (pix != -1)
            stripped = fileName.substring(pix+1);
        else
            stripped = fileName;

        // Make file info element for first message only
        String start = stripped + "\n" + fileSize;

        Message msg = null;
        byte[] buf = new byte[OBUFLEN];
        int n16kbufs = (int)(fileSize/OBUFLEN);
        int lastBufSize = (int)(fileSize % OBUFLEN);
        boolean infoDone = false;
        int offset = 0;
        long stime = System.currentTimeMillis();

        int chunks = n16kbufs + (int)(lastBufSize == 0 ? 0 : 1);

        println("sftp is connected to user " + name);
        println("Sending file " + fileName + ", size = " + fileSize + " bytes" +
                " in " +  chunks + " chunks");

        for (int i = 0; i < n16kbufs; i++) {
            try {
                // Build a message
                msg =  new Message();

                // set file info element in first message
                if (i == 0) {
                    infoDone = true;
                    // file info
                    msg.addMessageElement( new ByteArrayMessageElement( FileInfo, null, start.getBytes(), null ) );
                }
                // read the data
                fs.readFully(buf, 0, OBUFLEN);

                offset += OBUFLEN;

                // data elements
                msg.addMessageElement( new ByteArrayMessageElement( JftpData, null, buf, null) );

                // src name
                msg.addMessageElement( new ByteArrayMessageElement( SenderName, null, srcName.getBytes(), null) );

                pipeOut.send(msg);
                print("!");

            } catch (Exception e) {
                printStackTrace( "Failed to send file " + fileName + " to user :" + name, e );

                try {
                    fs.close();
                } catch (Exception ex) {
                    printStackTrace( "Close failed for " + fileName, ex );
                }
                pipeOut.close();
                return ShellApp.appMiscError;
            }
        }

        // See if we have one more buffer to send
        if (lastBufSize != 0) {
            try {
                // Build a message
                msg = new Message();

                // set file info element in first message only
                if (!infoDone) {
                    // file info
                    msg.addMessageElement( new ByteArrayMessageElement( FileInfo, null, start.getBytes(), null ) );
                }
                // read the data
                fs.readFully(buf, 0, lastBufSize);

                // data element
                msg.addMessageElement( new ByteArrayMessageElement( JftpData, null, buf, 0, lastBufSize, null ) );

                // src name element
                msg.addMessageElement( new ByteArrayMessageElement( SenderName, null, srcName.getBytes(), null ) );

                pipeOut.send(msg);
                print("!");

            } catch (Exception e) {
                printStackTrace( "Failed to send file " + fileName + " to user :" + name, e );
                try {
                    fs.close();
                } catch (Exception ex) {
                    printStackTrace( "Close failed for " + fileName, ex );
                }

                pipeOut.close();
                return ShellApp.appMiscError;
            }
        }