sftp.java

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        // K bytes per second calcul
        long elapsedTime = System.currentTimeMillis() - stime;

        // protect agains div by 0
        if (elapsedTime == 0)
            elapsedTime = 1;

        long kbpsec = (long)(((long)fileSize)/elapsedTime);

        float secs = (float)(((float)elapsedTime)/1000.0);

        println("\nSent: " + fileSize + " bytes in "  + secs + " secs[" +
                kbpsec + "Kbytes/sec]");

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

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


    private int registerNewUser(String[] args) {

        boolean secure = true;
        if( (args.length == 3) && ("-insecure".equals(args[2])) )
            secure = false;
        else
            if ((args.length != 2)) {
                return syntaxError();
            }

        String name = args[1];

        // Always secure
        String type = null;
        if( secure )
            type = PipeService.UnicastSecureType;
        else
            type = PipeService.UnicastType;

        // Check if there is already a registered user of the
        // same name.
        PipeAdvertisement adv = findUserAdv(name);
        if (adv != null) {
            consoleMessage("Sorry, user " + name + " is already registered");
            return ShellApp.appMiscError;
        }

        try {
            // Create a pipe advertisement for this pipe.
            adv = (PipeAdvertisement)
                  AdvertisementFactory.newAdvertisement(PipeAdvertisement.getAdvertisementType());
        } catch( Exception all ) {
            printStackTrace( "Advertisement document could not be created", all );
            return ShellApp.appMiscError;
        }

        ShellObject obj = env.get("stdgroup");
        // extract the advertisement
        PeerGroup group = (PeerGroup) obj.getObject();

        adv.setPipeID( IDFactory.newPipeID( (PeerGroupID) group.getPeerGroupID() ) );
        adv.setName(SftpNameTag + "." + name);
        adv.setType (type);

        try {
            // Save the document into the public folder
            discovery.publish(adv);
            discovery.remotePublish(adv);
        } catch (Exception e2) {
            printStackTrace( "Advertisement could not be saved", e2 );
            return ShellApp.appMiscError;
        }
        println("User : " + name + " is now registered");
        return ShellApp.appNoError;
    }

    // Make sure "name" is the advertised name
    private boolean checkUserAdv(PipeAdvertisement adv, String name) {

        if (adv == null)
            return false;
        if (adv.getName() == null)
            return false;

        String str = adv.getName();
        if (str.startsWith(SftpNameTag) &&  str.endsWith(name)) {
            return true;
        }
        return false;
    }


    private PipeAdvertisement findUserAdv(String name) {

        Enumeration each = null;

        // First look in the local storage
        try {
            each = discovery.getLocalAdvertisements(DiscoveryService.ADV,
                                                    PipeAdvertisement.NameTag,
                                                    SftpNameTag+".*");
            if ((each != null) && (each.hasMoreElements())) {
                PipeAdvertisement adv = null;
                while (each.hasMoreElements()) {
                    try {
                        adv = (PipeAdvertisement) each.nextElement();
                        if (adv.getName().endsWith(name)) {
                            if (checkUserAdv(adv, name)) {
                                return adv;
                            }
                        }
                    } catch(Exception e) {
                        continue;
                    }

                    if (checkUserAdv(adv, name)) {
                        return adv;
                    }
                }

            }
        } catch (Exception e) {
            printStackTrace( "Exception locating advertisement", e );
        }

        // Now, search remote
        discovery.getRemoteAdvertisements(null, DiscoveryService.ADV,
                                          PipeAdvertisement.NameTag,
                                          SftpNameTag + "." + name,
                                          2, null);

        // Wait a bit in order to get an answer.
        int i = 0;
        while (true) {
            try {
                if (i>MAXRETRIES) {
                    println("");
                    break;
                }
                Thread.sleep(WaitingTime);
                print(".");
                i++;
            } catch (Exception e) {
                printStackTrace( "Exception locating advertisement", e);
            }

            // Look in the local storage again
            try {
                each = discovery.getLocalAdvertisements(DiscoveryService.ADV,
                                                        PipeAdvertisement.NameTag,
                                                        SftpNameTag + "." + name);

                if ((each != null) && (each.hasMoreElements())) {
                    PipeAdvertisement adv = null;

                    while (each.hasMoreElements()) {

                        try {
                            adv = (PipeAdvertisement) each.nextElement();
                        } catch(Exception e) {
                            continue;
                        }

                        if (checkUserAdv(adv, name)) {
                            return adv;
                        }
                    }
                }
            } catch (Exception e) {
                printStackTrace( "Exception locating advertisement", e );
            }
        }
        // adv not found
        return null;
    }

    private void runDaemon(String name, PipeAdvertisement adv) {

        userAdv = adv;
        userName = name;
        thread = new Thread(this, "Jftpd:Jftpd Deamon" );
        thread.start();
        // Store this object
        ShellObject obj = env.add(EnvName + "." + name + "@" +
                                  (getGroup().getPeerGroupAdvertisement()).getName(),
                                  new ShellObject("Sftpd Deamon for " + name + "@" +
                                                  (getGroup().getPeerGroupAdvertisement()).getName(),
                                                  this));
    }

    private void stopDaemon(String name) {

        String dname = EnvName + "." + name + "@" +
                       (getGroup().getPeerGroupAdvertisement()).getName();

        ShellObject obj = env.get(dname);

        if (obj == null) {
            consoleMessage( "Daemon(" + dname + ") for " + name + " not found");
            return;
        }
        sftp d = null;
        try {
            d = (sftp) obj.getObject();
            d.thread.interrupt();
            env.remove(dname);
        } catch (Exception e) {
            printStackTrace( "cannot stop daemon for " + name, e );
        }
    }


    public void run() {

        try {

            InputPipe pipeIn = null;

            try {

                pipeIn = getGroup().getPipeService().createInputPipe(userAdv);

            } catch (Exception e) {
                return ;
            }

            if (pipeIn == null) {
                consoleMessage( "cannot open InputPipe");
                return;
            }

            // Listen on the pipe
            Message msg = null;

            // Message counter
            int i = 0;

            // Receive a file
            File f = null;
            FileOutputStream fout = null;
            String fileName = null;
            int fsize = 0;
            int offset = 0;
            long stime = 0;
            while (true) {

                try {
                    msg = pipeIn.waitForMessage();
                    if (msg == null) {
                        if (Thread.interrupted()) {
                            // We have been asked to stop
                            consoleMessage( "stop listening for user " + userName);
                            pipeIn.close();
                            return;
                        }
                        println("NULL msg");
                        continue;
                    }
                } catch (Exception e) {
                    // This exception probaly happened because the
                    // deamon has been interrupted. In any case, that
                    // shows that sftpd cannot receive messages anyway.
                    // clean up.
                    pipeIn.close();

                    return;
                }
                // Get the first tag
                InputStream ip = null;

                String senderName = "Anonymous";

                // Get the file information
                //   i == 0 on start or restart
                if (i++ == 0) {
                    fout = null;  // used as a flag
                    String fileInfo = (msg.getMessageElement(FileInfo)).toString();
                    if (fileInfo == null) {
                        // Something is broken
                        pipeIn.close();
                        consoleMessage( "bad message received. Stopping daemon for user :" +
                                        userName);
                        env.remove(EnvName + "." + userName + "@" +
                                   (getGroup().getPeerGroupAdvertisement()).getName());
                        return;
                    }

                    // open the file for output.
                    //   fileInfo == "filename\nfilesize"
                    int j = fileInfo.indexOf("\n");
                    fileName = fileInfo.substring(0, j);
                    String ofile = fdir + fileName;
                    try {
                        f = new File(ofile);
                        if (f.exists()) {
                            f.delete();
                        }
                        if (f.createNewFile()) {
                            fout = new FileOutputStream(f);
                        }
                    } catch (Exception e) {
                        printStackTrace( "Could not create output file " + ofile, e );
                        consoleMessage("Will receive but not write the data");
                        fout = null;
                    }

                    // file size
                    String filesize = fileInfo.substring(j+1);
                    Integer isize = new Integer(filesize);
                    fsize = isize.intValue();

                    // start at BOF
                    offset = 0;
                    stime = System.currentTimeMillis();
                }

                // Get sender information
                senderName = (msg.getMessageElement(SenderName)).toString();
                if (i == 1) {
                    println("\nReceive " + fileName + "[" + fsize + " bytes] from " +
                            senderName);
                }

                // write data to file
                byte[] data = (msg.getMessageElement(JftpData)).getBytes(false);
                if (data == null) {
                    println("sftpd: user " + senderName + " sent empty data");
                    continue;
                }

                if (fout != null) {
                    fout.write(data, 0, data.length);
                }

                // See if the file transfer is done
                offset += data.length;
                if (offset == fsize) {
                    println("! Done");
                    i = 0;
                    if (fout != null)
                        fout.close();

                    // elapsed time and bytes per sec.
                    long elapsedTime = System.currentTimeMillis() - stime;

                    // div by 0 check
                    if (elapsedTime == 0)
                        elapsedTime = 1;

                    long kbpsec = (long)(((long)fsize)/elapsedTime);
                    float secs = (float)(((float)elapsedTime)/1000.0);

                    println("Received: " + fsize + " bytes in "  + secs + " secs[" +
                            kbpsec + "Kbytes/sec]");
                } else {

                    print("!");

                }
            }
        } catch( Throwable all ) {
            printStackTrace( "Uncaught Throwable in thread :" + Thread.currentThread().getName(), all );
        }
    }

    public String getDescription() {
        return "Send a file to another peer";
    }

    public void help() {
        println("NAME");
        println("    sftp - send a file to another peer ");
        println(" ");
        println("SYNOPSIS");
        println(" ");
        println("    sftp -register <userName>");
        println("    sftp -login <userName>");
        println("    sftp -logout <userName>");
        println("    sftp -s <user> <userName> <fileName>");
        println(" ");
        println("DESCRIPTION");
        println(" ");
        println("The 'sftp command implements a secure file transfer");
        println("where one peer can send a file to a second.");
        println("to use 'sftp'. The user needs to register himself. This is done");
        println("via the following steps:");
        println("Step 1: Register via 'sftp -register <username>' command. This command");
        println("        creates a secure sftp advertisement for that user. This has to");
        println("        be done only once, the first time the user registers with");
        println("        sftp. The system remembers it across reboot.");
        println(" ");
        println("Step 2: Login  via 'sftp -login <username>' command. This command");
        println("        login the user and start a listener daemon. This has to");
        println("        to be done everytime the peer is restarted.");
        println(" ");
        println("Step 3: User can securely send a file to another user via the command");
        println("        'sftp -s <myusername> <destusername> <filename>'. This will send the");
        println("        file <filename> to the dest. The file is written on the sftp");
        println("        subdirectory of the directory where the shell is started.");
        println(" ");
        println("         JXTA>sftp -s moi mike photo.gif");
        println("         sftp is connected to user mike");
        println("         Sending file photo.gif, size = 55692 bytes");
        println("  ");
        println("To stop receiving any more files the user can stop the sftp");
        println("listener daemon by entering the command 'sftp -logout <username>'");
        println(" ");
        println("OPTIONS");
        println(" ");
        println("    -register register a new user name  ");
        println("    -login    log user and set default user");
        println("    -logout   logout");
        println("    -s        specify current user, and file names");
        println(" ");
        println("EXAMPLE");
        println(" ");
        println("      JXTA>sftp -register me");
        println("      JXTA>sftp -login me");
        println("      JXTA>sftp -s me you /tmp/nihow.jpg");
        println(" ");
        println("This example shows how a new user 'me'  can register and log into sftp,");
        println("and send a file to the user 'you'. User 'you' needs to be similarly");
        println("registered and logged on. The above file is written as sftp/nihow.jpg");
        println(" ");
        println("SEE ALSO");
    }

}