Ultr@VNC 1.0.0 RC19 Java Viewer =================================== Copyright (C) 2002-2005 Ultr@VNC Team. All Rights Reserved. Copyright (C) 2004 Kenn Min Chong, John Witchel. All Rights Reserved. Copyright (C) 2004 Alban Chazot. All Rights Reserved. Copyright (C) 2001,2002 HorizonLive.com, Inc. All Rights Reserved. Copyright (C) 2001,2002 Constantin Kaplinsky. All Rights Reserved. Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved. This software is distributed under the GNU General Public Licence as published by the Free Software Foundation. See the file LICENCE.TXT for the conditions under which this software is made available. VNC also contains code from other sources. See the Acknowledgements section below, and the individual files for details of the conditions under which they are made available. **************************************************************************** This JavaViewer supports Ultr@VNC FileTransfer ( >= RC19 protocole version) as well as Ultr@VNC MS Logon. So even from a Unix or Mac machine you can use a simple Web browser and do some FileTransfer with the UltraVNC Win32 Server, as well as taking advantage of the more secure MSLogon authentication method. When loaded in the WebBrowser (browsing http://YourUltraServerIP:5800), the user is prompted to accept or reject the Ultr@VNC JavaViewer applet signed certificate. It is necessary as this new JavaViewer does some FileTransfer and consequently needs to access the user's local drives. WARNING: This JavaViewer Applet can't be loaded using the default MS IE JVM as it doesn't support Swing. You must install a Java JVM (v1.3 or >). What still needs to be implemented as soon as possible (that is already in the Win32 Viewer): - Add files datetime and size in the files lists - Add files multi-selection for transfer - Add a "Parent Directory" button the the files panels. - Directory transfer - Delta transfer - ... NEW: added support for more color modes, usefull on slow connections: 64 Colors, 8 Colors, 2 B/W, 8 and 4 Grey Scale colors. Compiling and Running the JavaViewer ==================================== ** To compile the JavaViewer 1. Edit the "mk.bat" file and replace the path "c:\soft" with the path where your Java sdk stands. 2. Save and execute your mk.bat 3. If you want to sign the generated applet so it can be embedded into Ultra winvnc.exe and injected into web browsers on connections to port 5800, use the keytool.exe and jarsigner.exe programs that can be found in the Java sdk. 4. To replace the winvnc JavaViewer applet with your modifed and signed applet, copy the generated .class files and the vncviewer.jar file into winvnc\res directory and recompile WinVNC. ** To run this JavaViewer as a Java application, you must have the Java Runtime installed. 1. Edit the "run.bat" file and replace the path "c:\Ultravnc\JavaViewer" with the path where you've copied the JavaViewer, then replace "127.0.0.1" with the IP adress or network name of the machine where WinVNC server is running. 2. Save and Execute run.bat => If the path and adress you've written are correct, you should be prompted for the VNC password. If MS Logon is required on the server, you will also be prompted for Windows Username. Under Linux and Mac, you can also make a batchfile that executes this command: java.exe -cp **YourJavaViewerFullPath** VncViewer HOST **YourServerIP** PORT 5900 As soon as this new JavaViewer reaches the "beta" stage we'll put the source code in Ultr@VNC CVS repository. For now, the source code is available on demand only. If you know Java, have time and want to improve the Ultr@VNC project, your help would be greatly appreciated. Compiling from the sources ========================== To compile all the .java files to .class files, simply do: % make all This will also generate a JAR (Java archive) file containing all the classes. Copy all the .class files, the .jar file and the .vnc files to an installation directory (e.g. /usr/local/vnc/classes): % cp *.class *.jar *.vnc /usr/local/vnc/classes Make sure that the vncserver script is configured to point to the installation directory. Configuration ============= Ultr@VNC Java viewer supports a number of parameters allowing you to customize its behaviour. Most parameter names copy settings available from the Options frame in the Java viewer. Both parameter names and their values are case-insensitive, with one exception for the "PASSWORD" parameter. Here is the full list of parameters supported in Ultr@VNC Java viewer: --> "HOST" (no GUI equivalent) Value: host name or IP address of the VNC server. Default: in applet mode, the host from which the applet was loaded. This parameter tells the viewer which server to connect to. Normally, it's not needed, because default Java security policy allow connections from applets to the only one host anyway, and that is the host from which the applet was loaded. --> "PORT" (no GUI equivalent) Value: TCP port number on the VNC server. Default: none. This parameter is required in all cases. Note that this port is not the one used for HTTP connection from the browser, it is the port used for RFB connection. Usually, VNC servers use ports 58xx for HTTP connections, and ports 59xx for RFB connections. Thus, most likely, this parameter should be set to something like 5900, 5901 etc. --> "PASSWORD" Value: session password in plan text. Default: none, ask user. DO NOT EVER USE THIS PARAMETER, unless you really know what you are doing. It's extremely dangerous from the security point of view. When this parameter is set, the viewer won't ever ask for a password. --> "ENCPASSWORD" Value: encrypted session password in hex-ascii. Default: none, ask user. The same as the "PASSWORD" parameter but DES-encrypted using a fixed key. Its value should be represented in hex-ascii e.g. "494015f9a35e8b22". This parameter has higher priority over the "PASSWORD" parameter. DO NOT EVER USE THIS PARAMETER, unless you really know what you are doing. It's extremely dangerous from the security point of view, and encryption does not actually help here since the decryption key is always known. --> "Encoding" Values: "Raw", "RRE", "CoRRE", "Hextile", "Zlib", "Tight". Default: "Tight". The preferred encoding. "Hextile" is a good choice for fast networks, while "Tight" is better suited for low-bandwidth connections. From the other side, the "Tight" decoder in Ultr@VNC Java viewer seems to be more efficient than "Hextile" decoder so it's possible that this default setting can be ok for fast networks too. --> "Compression level" Values: "Default", "1", "2", "3", "4", "5", "6", "7", "8", "9". Default: "Default". ;-) Use specified compression level for "Tight" and "Zlib" encodings. Level 1 uses minimum of CPU time on the server but achieves weak compression ratios. Level 9 offers best compression but may be slow in terms of CPU time consumption on the server side. Use high levels with very slow network connections, and low levels when working over higher-speed networks. The "Default" value means that the server's default compression level should be used. --> "JPEG image quality" Values: "JPEG off", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9". Default: "6". Use the specified image quality level in "Tight" encoding. Quality level 0 denotes bad image quality but very impressive compression ratios, while level 9 offers very good image quality at lower compression ratios. If the value is "JPEG off", the server will not use lossy JPEG compression in "Tight" encoding. --> "Cursor shape updates" Values: "Enable", "Ignore", "Disable". Default: "Enable". Cursor shape updates is a protocol extension used to handle remote cursor movements locally on the client side, saving bandwidth and eliminating delays in mouse pointer movement. Note that current implementation of cursor shape updates does not allow a client to track mouse cursor position at the server side. This means that clients would not see mouse cursor movements if mouse was moved either locally on the server, or by another remote VNC client. Set this parameter to "Disable" if you always want to see real cursor position on the remote side. Setting this option to "Ignore" is similar to "Enable" but the remote cursor will not be visible at all. This can be a reasonable setting if you don't care about cursor shape and don't want to see two mouse cursors, one above another. --> "Use CopyRect" Values: "Yes", "No". Default: "Yes". The "CopyRect" encoding saves bandwidth and drawing time when parts of the remote screen are moving around. Most likely, you don't want to change this setting. --> "Restricted colors" Values: "Yes", "No". Default: "No". If set to "No", then 24-bit color format is used to represent pixel data. If set to "Yes", then only 8 bits are used to represent each pixel. 8-bit color format can save bandwidth, but colors may look very inaccurate. --> "Mouse buttons 2 and 3" Values: "Normal", "Reversed". Default: "Normal". If set to "Reversed", then right mouse button (button 2) will act as it was middle mouse button (button 3), and vice versa. --> "View only" Values: "Yes", "No". Default: "No". If set to "Yes", then all keyboard and mouse events in the desktop window will be silently ignored and will not be passed to the remote side. --> "Share desktop" Values: "Yes", "No". Default: "Yes". Share the connection with other clients on the same VNC server. The exact behaviour in each case depends on the server configuration. --> "Open new window" (no GUI equivalent, applicable only in the applet mode) Values: "Yes", "No". Default: "No". Operate in a separate window. This makes possible resizing the desktop, and adds scroll bars when necessary. If the server supports variable desktop size, the window will resize automatically when remote desktop size changes. --> "Show controls" (no GUI equivalent) Values: "Yes", "No". Default: "Yes". Set to "No" if you want to get rid of that button panel at the top. --> "Show offline desktop" (no GUI equivalent) Values: "Yes", "No". Default: "No". If set to "Yes", the viewer would continue to display desktop even if the remote side has closed the connection. In this case, if the button panel is enabled, then the "Disconnect" button would be changed to "Hide desktop" after the connection is lost. --> "Defer screen updates" (no GUI equivalent) Value: time in milliseconds. Default: "20". When updating the desktop contents after receiving an update from server, schedule repaint within the specified number of milliseconds. Small delay helps to coalesce several small updates into one drawing operation, improving CPU usage. Set this parameter to 0 to disable deferred updates. --> "Defer cursor updates" (no GUI equivalent) Value: time in milliseconds. Default: "10". When updating the desktop after moving the mouse, schedule repaint within the specified number of milliseconds. This setting makes sense only when "Cursor shape updates" parameter is set to "Enable". Small delay helps to coalesce several small updates into one drawing operation, improving CPU usage. Set this parameter to 0 to disable deferred cursor updates. --> "Defer update requests" (no GUI equivalent) Value: time in milliseconds. Default: "50". After processing an update received from server, wait for the specified number of milliseconds before requesting next screen update. Such delay will end immediately on every mouse or keyboard event if not in the "view only" mode. Small delay helps the server to coalesce several small updates into one framebuffer update, improving both bandwidth and CPU usage. Increasing the parameter value does not affect responsiveness on mouse and keyboard events, but causes delays in updating the screen when there is no mouse and keyboard activity on the client side. RECORDING VNC SESSIONS ====================== Current version of the Ultr@VNC Java viewer is able to record VNC (RFB) sessions in files for later playback. The data format in saved session files is compatible with the rfbproxy program written by Tim Waugh. Most important thing about session recording is that it's supported only if Java security manager allows access to local filesystem. Typically, it would not work for unsigned applets. To use this feature, either use Ultr@VNC Java viewer as a standalone application (Java Runtime Environment or Java Development Kit should be installed), or as a signed applet. The code checks if it's possible to support session recording, and if everything's fine, the new "Record" button should appear in the button panel. Pressing this button opens new window which controls session recording. The GUI is pretty self-explained. Other important facts about session recording: --> All sessions are recorded in the 24-bit color format. If you use restricted colors (8-bit format), it will be temporarly switched to 24-bit mode during session recording. --> All sessions are recorded with cursor shape updates turned off. This is necessary to represent remote cursor movements in recorded sessions. --> Closing and re-opening the recording control window does not affect the recording. It's not necessary to keep that window open during recording a session. --> Avoid using Zlib encoding when recording sessions. It's ok if you started recording BEFORE the connection to the VNC server has been established, but if you started recording during an active session, all Zlib sessions will be saved Raw-encoded (that is, without compression at all). Zlib decoding depends on the pixel data received earlier, thus saving the data received from the server at an arbitrary moment is not sufficient to decompress it correctly. And there is no way to say Zlib decoder to reset decompressor's state -- that's a limitation of the Zlib encoder. The viewer could re-compress raw pixel data again before saving Zlib-encoded sessions, but unfortunately Java API does not allow to flush zlib data streams making it impossible to save Zlib-encoded RFB pixel data without using native code. --> Usually, Tight encoding is the most suitable one for session recording, but some of the issues described above for the Zlib encoding affect the Tight encoding as well. Unlike Zlib sessions, Tight-encoded sessions are always saved Tight-encoded, but the viewer has to re-compress parts of data to synchronize encoder's and decoder's zlib streams. And, due to Java zlib API limitations, zlib streams' states have to be reset on each compressed rectangle, causing compression ratios to be lower than in the original VNC session. If you want to achieve the best possible performance, turn recording on BEFORE connecting to the VNC server, otherwise CPU usage and compression ratios may be notably less efficient. HINTS ===== --> To refresh remote desktop in the view-only mode, press "r" or "R" on the keyboard. ACKNOWLEDGEMENTS ================ This distribution contains Java DES software by Dave Zimmerman and Jef Poskanzer . This is: Copyright (c) 1996 Widget Workshop, Inc. All Rights Reserved. Permission to use, copy, modify, and distribute this software and its documentation for NON-COMMERCIAL or COMMERCIAL purposes and without fee is hereby granted, provided that this copyright notice is kept intact. WIDGET WORKSHOP MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. WIDGET WORKSHOP SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. THIS SOFTWARE IS NOT DESIGNED OR INTENDED FOR USE OR RESALE AS ON-LINE CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING FAIL-SAFE PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES, AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE SOFTWARE COULD LEAD DIRECTLY TO DEATH, PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH RISK ACTIVITIES"). WIDGET WORKSHOP SPECIFICALLY DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES. Copyright (C) 1996 by Jef Poskanzer . 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. THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS 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 THE AUTHOR OR 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. 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