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path: root/java/com/tigervnc/vncviewer/VncViewer.java
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/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
 * Copyright 2011 Pierre Ossman <ossman@cendio.se> for Cendio AB
 * Copyright (C) 2011-2013 D. R. Commander.  All Rights Reserved.
 * Copyright (C) 2011-2014 Brian P. Hinz
 *
 * 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 of the License, or
 * (at your option) any later version.
 *
 * This software 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; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA.
 */

//
// VncViewer - the VNC viewer applet.  It can also be run from the
// command-line, when it behaves as much as possibly like the windows and unix
// viewers.
//
// Unfortunately, because of the way Java classes are loaded on demand, only
// configuration parameters defined in this file can be set from the command
// line or in applet parameters.

package com.tigervnc.vncviewer;

import java.awt.*;
import java.awt.event.*;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.io.InputStream;
import java.io.IOException;
import java.io.File;
import java.lang.Character;
import java.lang.reflect.*;
import java.util.jar.Attributes;
import java.util.jar.Manifest;
import java.util.*;
import javax.swing.*;
import javax.swing.plaf.FontUIResource;
import javax.swing.UIManager.*;

import com.tigervnc.rdr.*;
import com.tigervnc.rfb.*;
import com.tigervnc.network.*;

public class VncViewer extends javax.swing.JApplet 
  implements Runnable, ActionListener {

  public static final String aboutText = new String("TigerVNC Java Viewer v%s (%s)%n"+
                                                    "Built on %s at %s%n"+
                                                    "Copyright (C) 1999-2013 TigerVNC Team and many others (see README.txt)%n"+
                                                    "See http://www.tigervnc.org for information on TigerVNC.");

  public static String version = null;
  public static String build = null;
  public static String buildDate = null;
  public static String buildTime = null;
  static ImageIcon frameIconSrc =
    new ImageIcon(VncViewer.class.getResource("tigervnc.ico"));
  public static final Image frameIcon = frameIconSrc.getImage();
  public static final ImageIcon logoIcon =
    new ImageIcon(VncViewer.class.getResource("tigervnc.png"));
  public static final Image logoImage = logoIcon.getImage();
  public static final InputStream timestamp =
    VncViewer.class.getResourceAsStream("timestamp");
  public static final String os = 
    System.getProperty("os.name").toLowerCase();

  public static void setLookAndFeel() {
    try {
      if (os.startsWith("mac os x")) {
        Class appClass = Class.forName("com.apple.eawt.Application");
        Method getApplication = 
          appClass.getMethod("getApplication", (Class[])null);
        Object app = getApplication.invoke(appClass);
        Class paramTypes[] = new Class[1];
        paramTypes[0] = Image.class;
        Method setDockIconImage = 
          appClass.getMethod("setDockIconImage", paramTypes);
        setDockIconImage.invoke(app, VncViewer.logoImage);
      }
      // Use Nimbus LookAndFeel if it's available, otherwise fallback
      // to the native laf, or Metal if no native laf is available.
      String laf = System.getProperty("swing.defaultlaf");
      if (laf == null) {
        LookAndFeelInfo[] installedLafs = UIManager.getInstalledLookAndFeels();
        for (int i = 0; i < installedLafs.length; i++) {
          if (installedLafs[i].getName().equals("Nimbus"))
            laf = installedLafs[i].getClassName();
        }
        if (laf == null)
          UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
      }
      UIManager.setLookAndFeel(laf);
      UIManager.put("TitledBorder.titleColor",Color.blue);
      if (UIManager.getLookAndFeel().getName().equals("Metal")) {
        UIManager.put("swing.boldMetal", Boolean.FALSE);
        Enumeration<Object> keys = UIManager.getDefaults().keys();
        while (keys.hasMoreElements()) {
          Object key = keys.nextElement();
          Object value = UIManager.get(key);
          if (value instanceof FontUIResource) {
            String name = ((FontUIResource)value).getName();
            int style = ((FontUIResource)value).getStyle();
            int size = ((FontUIResource)value).getSize()-1;
            FontUIResource f = new FontUIResource(name, style, size);
            UIManager.put(key, f);
          }
        }
      } else if (UIManager.getLookAndFeel().getName().equals("Nimbus")) {
        Font f = UIManager.getFont("TitledBorder.font");
        String name = f.getName();
        int style = f.getStyle();
        int size = f.getSize()-2;
        FontUIResource r = new FontUIResource(name, style, size);
      	UIManager.put("TitledBorder.font", r);
      }
    } catch (java.lang.Exception e) {
      vlog.info(e.toString());
    }
  }

  public static void main(String[] argv) {
    setLookAndFeel();
    VncViewer viewer = new VncViewer(argv);
    viewer.start();
  }


  public VncViewer(String[] argv) {
    embed.setParam(false);

    // load user preferences
    UserPreferences.load("global");

    SecurityClient.setDefaults();

    // Write about text to console, still using normal locale codeset
    getTimestamp();
    System.err.format("%n");
    System.err.format(aboutText, version, build, buildDate, buildTime);
    System.err.format("%n");

    Configuration.enableViewerParams();

    // Override defaults with command-line options
    for (int i = 0; i < argv.length; i++) {
      if (argv[i].length() == 0)
        continue;

      if (argv[i].equalsIgnoreCase("-config")) {
        if (++i >= argv.length) usage();
          Configuration.load(argv[i]);
        continue;
      }

      if (argv[i].equalsIgnoreCase("-log")) {
        if (++i >= argv.length) usage();
        System.err.println("Log setting: "+argv[i]);
        LogWriter.setLogParams(argv[i]);
        continue;
      }

      if (argv[i].equalsIgnoreCase("-tunnel") || argv[i].equalsIgnoreCase("-via")) {
        if (!tunnel.createTunnel(argv.length, argv, i))
          exit(1);
        if (argv[i].equalsIgnoreCase("-via")) i++;
        continue;
      }

      if (Configuration.setParam(argv[i]))
        continue;

      if (argv[i].charAt(0) == '-') {
        if (i+1 < argv.length) {
          if (Configuration.setParam(argv[i].substring(1), argv[i+1])) {
            i++;
            continue;
          }
        }
        usage();
      }

      if (vncServerName.getValue() != null)
        usage();
      vncServerName.setParam(argv[i]);
    }

    if (!autoSelect.hasBeenSet()) {
      // Default to AutoSelect=0 if -PreferredEncoding or -FullColor is used
      autoSelect.setParam(!preferredEncoding.hasBeenSet() &&
                          !fullColour.hasBeenSet() &&
                          !fullColourAlias.hasBeenSet());
    }
    if (!fullColour.hasBeenSet() && !fullColourAlias.hasBeenSet()) {
      // Default to FullColor=0 if AutoSelect=0 && LowColorLevel is set
      if (!autoSelect.getValue() && (lowColourLevel.hasBeenSet() ||
                          lowColourLevelAlias.hasBeenSet())) {
        fullColour.setParam(false);
      }
    }
    if (!customCompressLevel.hasBeenSet()) {
      // Default to CustomCompressLevel=1 if CompressLevel is used.
      customCompressLevel.setParam(compressLevel.hasBeenSet());
    }
  }

  public static void usage() {
    String usage = ("\nusage: vncviewer [options/parameters] "+
                    "[host:displayNum]\n"+
                    "       vncviewer [options/parameters] -listen [port] "+
                    "[options/parameters]\n"+
                    "\n"+
                    "Options:\n"+
                    "  -log <level>    configure logging level\n"+
                    "\n"+
                    "Parameters can be turned on with -<param> or off with "+
                    "-<param>=0\n"+
                    "Parameters which take a value can be specified as "+
                    "-<param> <value>\n"+
                    "Other valid forms are <param>=<value> -<param>=<value> "+
                    "--<param>=<value>\n"+
                    "Parameter names are case-insensitive.  The parameters "+
                    "are:\n"+
                    "\n");
    System.err.print(usage);

    Configuration.listParams(79, 14);
    String propertiesString = ("\n"+
"System Properties (adapted from the TurboVNC vncviewer man page)\n"+
"  When started with the -via option, vncviewer reads the VNC_VIA_CMD\n"+
"  System property, expands patterns beginning with the \"%\" character,\n"+
"  and uses the resulting command line to establish the secure tunnel\n"+
"  to the VNC gateway.  If VNC_VIA_CMD is not set, this command line\n"+
"  defaults to \"/usr/bin/ssh -f -L %L:%H:%R %G sleep 20\".\n"+
"\n"+
"  The following patterns are recognized in the VNC_VIA_CMD property\n"+
"  (note that all of the patterns %G, %H, %L and %R must be present in \n"+
"  the command template):\n"+
"\n"+
"  \t%%     A literal \"%\";\n"+
"\n"+
"  \t%G     gateway machine name;\n"+
"\n"+
"  \t%H     remote VNC machine name, (as known to the gateway);\n"+
"\n"+
"  \t%L     local TCP port number;\n"+
"\n"+
"  \t%R     remote TCP port number.\n"+
"\n"+
"  When started with the -tunnel option, vncviewer reads the VNC_TUNNEL_CMD\n"+
"  System property, expands patterns beginning with the \"%\" character, and\n"+
"  uses the resulting command line to establish the secure tunnel to the\n"+
"  VNC server.  If VNC_TUNNEL_CMD is not set, this command line defaults\n"+
"  to \"/usr/bin/ssh -f -L %L:localhost:%R %H sleep 20\".\n"+
"\n"+
"  The following patterns are recognized in the VNC_TUNNEL_CMD property\n"+
"  (note that all of the patterns %H, %L and %R must be present in \n"+
"  the command template):\n"+
"\n"+
"  \t%%     A literal \"%\";\n"+
"\n"+
"  \t%H     remote VNC machine name (as known to the client);\n"+
"\n"+
"  \t%L     local TCP port number;\n"+
"\n"+
"  \t%R     remote TCP port number.\n"+
"\n");
    System.err.print(propertiesString);
    // Technically, we shouldn't use System.exit here but if there is a parameter
    // error then the problem is in the index/html file anyway.
    System.exit(1);
  }

  public VncViewer() {
    UserPreferences.load("global");
    embed.setParam(true);
  }

  public static void newViewer(VncViewer oldViewer, Socket sock, boolean close) {
    VncViewer viewer = new VncViewer();
    viewer.embed.setParam(oldViewer.embed.getValue());
    viewer.sock = sock;
    viewer.start();
    if (close)
      oldViewer.exit(0);
  }

  public static void newViewer(VncViewer oldViewer, Socket sock) {
    newViewer(oldViewer, sock, false);
  }

  public static void newViewer(VncViewer oldViewer) {
    newViewer(oldViewer, null);
  }

  public boolean isAppletDragStart(MouseEvent e) {
    if(e.getID() == MouseEvent.MOUSE_DRAGGED) {
      // Drag undocking on Mac works, but introduces a host of
      // problems so disable it for now.
      if (os.startsWith("mac os x"))
        return false;
      else if (os.startsWith("windows"))
        return (e.getModifiersEx() & MouseEvent.ALT_DOWN_MASK) != 0;
      else
        return (e.getModifiersEx() & MouseEvent.SHIFT_DOWN_MASK) != 0;
    } else {
      return false;
    }
  }

  public void appletDragStarted() {
    embed.setParam(false);
    cc.recreateViewport();
    JFrame f = (JFrame)JOptionPane.getFrameForComponent(this);
    // The default JFrame created by the drag event will be
    // visible briefly between appletDragStarted and Finished.
    if (f != null)
      f.setSize(0, 0);
  }

  public void appletDragFinished() {
    cc.setEmbeddedFeatures(true);
    JFrame f = (JFrame)JOptionPane.getFrameForComponent(this);
    if (f != null)
      f.dispose();
  }

  public void setAppletCloseListener(ActionListener cl) {
    cc.setCloseListener(cl);
  }

  public void appletRestored() {
    cc.setEmbeddedFeatures(false);
    cc.setCloseListener(null);
  }

  public void init() {
    vlog.debug("init called");
    Container parent = getParent();
    while (!parent.isFocusCycleRoot()) {
      parent = parent.getParent();
    }
    ((Frame)parent).setModalExclusionType(null);
    parent.setFocusable(false);
    parent.setFocusTraversalKeysEnabled(false);
    setLookAndFeel();
    setBackground(Color.white);
  }

  private void getTimestamp() {
    if (version == null || build == null) {
      try {
        Manifest manifest = new Manifest(timestamp);
        Attributes attributes = manifest.getMainAttributes();
        version = attributes.getValue("Version");
        build = attributes.getValue("Build");
        buildDate = attributes.getValue("Package-Date");
        buildTime = attributes.getValue("Package-Time");
      } catch (java.io.IOException e) { }
    }
  }

  public void start() {
    vlog.debug("start called");
    getTimestamp();
    if (embed.getValue() && nViewers == 0) {
      alwaysShowServerDialog.setParam(true);
      Configuration.global().readAppletParams(this);
      fullScreen.setParam(false);
      scalingFactor.setParam("100");
      String host = getCodeBase().getHost();
      if (vncServerName.getValue() == null && vncServerPort.getValue() != 0) {
        int port = vncServerPort.getValue();
        vncServerName.setParam(host + ((port >= 5900 && port <= 5999)
                                       ? (":"+(port-5900))
                                       : ("::"+port)));
      }
    }
    nViewers++;
    thread = new Thread(this);
    thread.start();
  }

  public void exit(int n) {
    nViewers--;
    if (nViewers > 0)
      return;
    if (embed.getValue())
      destroy();
    else
      System.exit(n);
  }

  // If "Reconnect" button is pressed
  public void actionPerformed(ActionEvent e) {
    getContentPane().removeAll();
    start();
  }

  void reportException(java.lang.Exception e) {
    String title, msg = e.getMessage();
    int msgType = JOptionPane.ERROR_MESSAGE;
    title = "TigerVNC Viewer : Error";
    e.printStackTrace();
    if (embed.getValue()) {
      getContentPane().removeAll();
      JLabel label = new JLabel("<html><center><b>" + title + "</b><p><i>" +
                                msg + "</i></center></html>", JLabel.CENTER);
      label.setFont(new Font("Helvetica", Font.PLAIN, 24));
      label.setMaximumSize(new Dimension(getSize().width, 100));
      label.setVerticalAlignment(JLabel.CENTER);
      label.setAlignmentX(Component.CENTER_ALIGNMENT);
      JButton button = new JButton("Reconnect");
      button.addActionListener(this);
      button.setMaximumSize(new Dimension(200, 30));
      button.setAlignmentX(Component.CENTER_ALIGNMENT);
      setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));
      add(label);
      add(button);
      validate();
      repaint();
    } else {
      JOptionPane.showMessageDialog(null, msg, title, msgType);
    }
  }

  CConn cc;
  public void run() {
    cc = null;

    if (listenMode.getValue()) {
      int port = 5500;

      if (vncServerName.getValue() != null &&
          Character.isDigit(vncServerName.getValue().charAt(0)))
        port = Integer.parseInt(vncServerName.getValue());

      TcpListener listener = null;
      try {
        listener = new TcpListener(null, port);
      } catch (java.lang.Exception e) {
        reportException(e);
        exit(1);
      }

      vlog.info("Listening on port "+port);

      while (true) {
        Socket new_sock = listener.accept();
        if (new_sock != null)
          newViewer(this, new_sock);
      }
    }

    try {
      cc = new CConn(this, sock, vncServerName.getValue());
      while (!cc.shuttingDown)
        cc.processMsg();
    } catch (java.lang.Exception e) {
      if (cc == null || !cc.shuttingDown) {
        reportException(e);
        if (cc != null)
          cc.deleteWindow();
        exit(1);
      } else if (embed.getValue()) {
        reportException(new java.lang.Exception("Connection closed"));
      } else {
        cc = null;
      }
    }
    exit(0);
  }

  // On Mac systems, setting this parameter will force the use of the old
  // (pre-Lion) full-screen mode, even if the viewer is running on OS X 10.7
  // "Lion" or later.
  static BoolParameter noLionFS
  = new BoolParameter("NoLionFS", null, false);

  BoolParameter embed
  = new BoolParameter("Embed",
  "If the viewer is being run as an applet, display its output to " +
  "an embedded frame in the browser window rather than to a dedicated " +
  "window.  This also has the effect of setting FullScreen=0, and Scale=100.",
  false);

  BoolParameter useLocalCursor
  = new BoolParameter("UseLocalCursor",
                      "Render the mouse cursor locally",
                      true);
  BoolParameter sendLocalUsername
  = new BoolParameter("SendLocalUsername",
                      "Send the local username for SecurityTypes "+
                      "such as Plain rather than prompting",
                      true);
  StringParameter passwordFile
  = new StringParameter("PasswordFile",
                        "Password file for VNC authentication",
                        "");
  AliasParameter passwd
  = new AliasParameter("passwd",
                       "Alias for PasswordFile",
                       passwordFile);
  BoolParameter autoSelect
  = new BoolParameter("AutoSelect",
                      "Auto select pixel format and encoding",
                      true);
  BoolParameter fullColour
  = new BoolParameter("FullColour",
                      "Use full colour - otherwise 6-bit colour is "+
                      "used until AutoSelect decides the link is "+
                      "fast enough",
                      true);
  AliasParameter fullColourAlias
  = new AliasParameter("FullColor",
                       "Alias for FullColour",
                       fullColour);
  IntParameter lowColourLevel
  = new IntParameter("LowColorLevel",
                     "Color level to use on slow connections. "+
                     "0 = Very Low (8 colors), 1 = Low (64 colors), "+
                     "2 = Medium (256 colors)",
                     2);
  AliasParameter lowColourLevelAlias
  = new AliasParameter("LowColourLevel",
                       "Alias for LowColorLevel",
                       lowColourLevel);
  StringParameter preferredEncoding
  = new StringParameter("PreferredEncoding",
                        "Preferred encoding to use (Tight, ZRLE, "+
                        "hextile or raw) - implies AutoSelect=0",
                        "Tight");
  BoolParameter viewOnly
  = new BoolParameter("ViewOnly",
                      "Don't send any mouse or keyboard events to "+
                      "the server",
                      false);
  BoolParameter shared
  = new BoolParameter("Shared",
                      "Don't disconnect other viewers upon "+
                      "connection - share the desktop instead",
                      false);
  BoolParameter fullScreen
  = new BoolParameter("FullScreen",
                      "Full Screen Mode",
                      false);
  BoolParameter acceptClipboard
  = new BoolParameter("AcceptClipboard",
                      "Accept clipboard changes from the server",
                      true);
  BoolParameter sendClipboard
  = new BoolParameter("SendClipboard",
                      "Send clipboard changes to the server",
                      true);
  IntParameter maxCutText
  = new IntParameter("MaxCutText",
                     "Maximum permitted length of an outgoing clipboard update",
                     262144);
  StringParameter menuKey
  = new StringParameter("MenuKey",
                        "The key which brings up the popup menu",
                        "F8");
  StringParameter desktopSize
  = new StringParameter("DesktopSize",
                        "Reconfigure desktop size on the server on "+
                        "connect (if possible)", "");
  BoolParameter listenMode
  = new BoolParameter("listen",
                      "Listen for connections from VNC servers",
                      false);
  StringParameter scalingFactor
  = new StringParameter("ScalingFactor",
                        "Reduce or enlarge the remote desktop image. "+
                        "The value is interpreted as a scaling factor "+
                        "in percent. If the parameter is set to "+
                        "\"Auto\", then automatic scaling is "+
                        "performed. Auto-scaling tries to choose a "+
                        "scaling factor in such a way that the whole "+
                        "remote desktop will fit on the local screen. "+
                        "If the parameter is set to \"FixedRatio\", "+
                        "then automatic scaling is performed, but the "+
                        "original aspect ratio is preserved.",
                        "100");
  BoolParameter alwaysShowServerDialog
  = new BoolParameter("AlwaysShowServerDialog",
                      "Always show the server dialog even if a server "+
                      "has been specified in an applet parameter or on "+
                      "the command line",
                      false);
  StringParameter vncServerName
  = new StringParameter("Server",
                        "The VNC server <host>[:<dpyNum>] or "+
                        "<host>::<port>",
                        null);
  IntParameter vncServerPort
  = new IntParameter("Port",
                     "The VNC server's port number, assuming it is on "+
                     "the host from which the applet was downloaded",
                     0);
  BoolParameter acceptBell
  = new BoolParameter("AcceptBell",
                      "Produce a system beep when requested to by the server.",
                      true);
  StringParameter via
  = new StringParameter("via",
    "Automatically create an encrypted TCP tunnel to "+
    "machine gateway, then use that tunnel to connect "+
    "to a VNC server running on host. By default, "+
    "this option invokes SSH local port forwarding and "+
    "assumes that the SSH client binary is located at "+
    "/usr/bin/ssh. Note that when using the -via "+
    "option, the host machine name should be specified "+
    "from the point of view of the gateway machine. "+
    "For example, \"localhost\" denotes the gateway, "+
    "not the machine on which vncviewer was launched. "+
    "See the System Properties section below for "+
    "information on configuring the -via option.",
    null);

  StringParameter tunnelMode
  = new StringParameter("tunnel",
    "Automatically create an encrypted TCP tunnel to "+
    "remote gateway, then use that tunnel to connect "+
    "to the specified VNC server port on the remote "+
    "host. See the System Properties section below "+
    "for information on configuring the -tunnel option.",
    null);

  BoolParameter customCompressLevel
  = new BoolParameter("CustomCompressLevel",
                      "Use custom compression level. "+
                      "Default if CompressLevel is specified.",
                      false);
  IntParameter compressLevel
  = new IntParameter("CompressLevel",
                     "Use specified compression level "+
                     "0 = Low, 6 = High",
                     1);
  BoolParameter noJpeg
  = new BoolParameter("NoJPEG",
                      "Disable lossy JPEG compression in Tight encoding.",
                      false);
  IntParameter qualityLevel
  = new IntParameter("QualityLevel",
                     "JPEG quality level. "+
                     "0 = Low, 9 = High",
                     8);

  StringParameter config
  = new StringParameter("config",
  "Specifies a configuration file to load.", null);

  Thread thread;
  Socket sock;
  static int nViewers;
  static LogWriter vlog = new LogWriter("main");
}