/* * This file is part of "The Java Telnet Application". * * This is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * "The Java Telnet Application" is distributed in the hope that it will be  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. *  * You should have received a copy of the GNU General Public License * along with this software; see the file COPYING.  If not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */package de.mud.jta.plugin;import de.mud.jta.Plugin;import de.mud.jta.FilterPlugin;import de.mud.jta.PluginBus;import de.mud.jta.PluginConfig;import de.mud.jta.event.ConfigurationListener;import de.mud.jta.event.OnlineStatusListener;import de.mud.jta.event.TerminalTypeRequest;import de.mud.jta.event.WindowSizeRequest;import de.mud.jta.event.LocalEchoRequest;import de.mud.ssh.SshIO;import java.awt.Dimension;import java.awt.Frame;import java.awt.Dialog;import java.awt.Panel;import java.awt.Button;import java.awt.Label;import java.awt.TextField;import java.awt.GridLayout;import java.awt.event.ActionListener;import java.awt.event.ActionEvent;import java.io.IOException;/** * Secure Shell plugin for the Java Telnet Application. This is a plugin * to be used instead of Telnet for secure remote terminal sessions over * insecure networks. The implementation uses code that was derived from * </I>Cedric Gourio</I>'s implementation that used parts of the old Java * Telnet Applet. Have a look at the package de.mud.ssh for further information * about ssh or look at the official ssh homepage: * <A HREF="http://www.ssh.org/">http://www.ssh.fi/</A>. * <P> * <B>Maintainer:</B> Matthias L. Jugel * * @version $Id: SSH.java,v 1.15 2001/05/09 12:52:45 leo Exp $ * @author Matthias L. Jugel, Marcus Mei遪er */public class SSH extends Plugin implements FilterPlugin {  protected FilterPlugin source;  protected SshIO handler;  protected String user, pass;  private final static int debug = 0;  private boolean auth = false;  /**   * Create a new ssh plugin.   */  public SSH(final PluginBus bus, final String id) {    super(bus, id);    // create a new telnet protocol handler    handler = new SshIO() {      /** get the current terminal type */      public String getTerminalType() {        return (String)bus.broadcast(new TerminalTypeRequest());      }      /** get the current window size */      public Dimension getWindowSize() {        return (Dimension)bus.broadcast(new WindowSizeRequest());      }      /** notify about local echo */      public void setLocalEcho(boolean echo) {        bus.broadcast(new LocalEchoRequest(echo));      }      /** write data to our back end */      public void write(byte[] b) throws IOException {        source.write(b);      }    };    bus.registerPluginListener(new ConfigurationListener() {      public void setConfiguration(PluginConfig config) {        user = config.getProperty("SSH", id, "user");	pass = config.getProperty("SSH", id, "password");      }    });    // reset the protocol handler just in case :-)    bus.registerPluginListener(new OnlineStatusListener() {      public void online() {	if(pass == null) {          final Frame frame = new Frame("SSH User Authentication");          Panel panel = new Panel(new GridLayout(3,1));	  panel.add(new Label("SSH Authorization required"));	  panel.add(new Label("SSH implementation 1998 by Cedric Gourio"));          panel.add(new Label("Adapted 1999 to the JTA by Matthias L. Jugel"));	  frame.add("North", panel);          panel = new Panel(new GridLayout(2,2));	  final TextField login = new TextField(user, 10);	  final TextField passw = new TextField(10);	  login.addActionListener(new ActionListener() {	    public void actionPerformed(ActionEvent evt) {	      passw.requestFocus();	    }	  });	  passw.setEchoChar('*');	  panel.add(new Label("User name")); panel.add(login);	  panel.add(new Label("Password")); panel.add(passw);	  frame.add("Center", panel);	  panel = new Panel();	  Button cancel = new Button("Cancel");	  Button ok = new Button("Login");	  ActionListener enter = new ActionListener() {	    public void actionPerformed(ActionEvent evt) {	      handler.setLogin(login.getText());	      handler.setPassword(passw.getText());	      frame.dispose();	      auth = true;	    }	  };	  ok.addActionListener(enter);	  passw.addActionListener(enter);	  cancel.addActionListener(new ActionListener() {	    public void actionPerformed(ActionEvent evt) {	      frame.dispose();	    }	  });	  panel.add(cancel);	  panel.add(ok);	  frame.add("South", panel);  	  frame.pack();	  frame.show();	  frame.setLocation(frame.getToolkit().getScreenSize().width/2 -	                    frame.getSize().width/2, 	                    frame.getToolkit().getScreenSize().height/2 -	                    frame.getSize().height/2);	} else {	  error(user+":"+pass);	  handler.setLogin(user);	  handler.setPassword(pass);	  auth = true;	}      }      public void offline() {        handler.disconnect();	auth=false;      }    });  }  public void setFilterSource(FilterPlugin source) {     if(debug>0) System.err.println("ssh: connected to: "+source);    this.source = source;  }  private byte buffer[];  private int pos;  /**   * Read data from the backend and decrypt it. This is a buffering read   * as the encrypted information is usually smaller than its decrypted   * pendant. So it will not read from the backend as long as there is   * data in the buffer.   * @param b the buffer where to read the decrypted data in   * @return the amount of bytes actually read.   */  public int read(byte[] b) throws IOException {    // we don't want to read from the pipeline without authorization    while(!auth) try {      Thread.sleep(1000);    } catch(InterruptedException e) {      e.printStackTrace();    }    // empty the buffer before we do anything else    if(buffer != null) {      int amount = (buffer.length - pos) <= b.length ?                       buffer.length - pos : b.length;      System.arraycopy(buffer, pos, b, 0, amount);      if(pos + amount < buffer.length) {        pos += amount;      } else         buffer = null;      return amount;    }     // now that the buffer is empty let's read more data and decrypt it    int n = source.read(b);    if(n > 0) {      byte[] tmp = new byte[n];      System.arraycopy(b, 0, tmp, 0, n);      buffer = handler.handleSSH(tmp);      if(debug > 0 && buffer != null && buffer.length > 0)        System.err.println("ssh: "+new String(buffer));      if(buffer != null && buffer.length > 0) {        if(debug > 0) 	  System.err.println("ssh: incoming="+n+" now="+buffer.length);	int amount = buffer.length <= b.length ?  buffer.length : b.length;        System.arraycopy(buffer, 0, b, 0, amount);	pos = n = amount;	if(amount == buffer.length) {	  buffer = null;	  pos = 0;	}      } else        return 0;    }    return n;  }  /**   * Write data to the back end. This hands the data over to the ssh   * protocol handler who encrypts the information and writes it to   * the actual back end pipe.   * @param b the unencrypted data to be encrypted and sent   */  public void write(byte[] b) throws IOException {    // no write until authorization is done    if(!auth) return;    for (int i=0;i<b.length;i++) {    	switch (b[i]) { 	case 10: /* \n -> \r */		b[i] = 13;		break;	}    }    handler.sendData(new String(b));  }}