mirror of
https://github.com/gyurix1968/guacamole-client.git
synced 2025-09-10 15:11:22 +00:00
Remove central guac-dev repo reference. Refactor net.sourceforge.guacamole to org.glyptodon.guacamole. Extensions are remaining with their classes in net.sourceforge.guacamole for compatibility's sake until we have a better system for extensions.
This commit is contained in:
Michael Jumper
@@ -0,0 +1,452 @@
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package org.glyptodon.guacamole.servlet;
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/* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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*
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* License.
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*
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* The Original Code is guacamole-common.
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*
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* The Initial Developer of the Original Code is
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* Michael Jumper.
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* Portions created by the Initial Developer are Copyright (C) 2010
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* the Initial Developer. All Rights Reserved.
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*
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* Contributor(s):
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*
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* Alternatively, the contents of this file may be used under the terms of
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* either the GNU General Public License Version 2 or later (the "GPL"), or
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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*
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* ***** END LICENSE BLOCK ***** */
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import java.io.BufferedWriter;
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import java.io.IOException;
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import java.io.InputStreamReader;
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import java.io.OutputStreamWriter;
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import java.io.Reader;
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import java.io.Writer;
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import javax.servlet.ServletException;
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import javax.servlet.http.HttpServlet;
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import javax.servlet.http.HttpServletRequest;
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import javax.servlet.http.HttpServletResponse;
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import javax.servlet.http.HttpSession;
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import org.glyptodon.guacamole.GuacamoleClientException;
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import org.glyptodon.guacamole.GuacamoleException;
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import org.glyptodon.guacamole.GuacamoleResourceNotFoundException;
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import org.glyptodon.guacamole.GuacamoleSecurityException;
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import org.glyptodon.guacamole.GuacamoleServerException;
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import org.glyptodon.guacamole.io.GuacamoleReader;
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import org.glyptodon.guacamole.io.GuacamoleWriter;
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import org.glyptodon.guacamole.net.GuacamoleTunnel;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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/**
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* A HttpServlet implementing and abstracting the operations required by the
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* HTTP implementation of the JavaScript Guacamole client's tunnel.
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*
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* @author Michael Jumper
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*/
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public abstract class GuacamoleHTTPTunnelServlet extends HttpServlet {
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/**
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* Logger for this class.
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*/
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private Logger logger = LoggerFactory.getLogger(GuacamoleHTTPTunnelServlet.class);
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/**
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* The prefix of the query string which denotes a tunnel read operation.
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*/
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private static final String READ_PREFIX = "read:";
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/**
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* The prefix of the query string which denotes a tunnel write operation.
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*/
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private static final String WRITE_PREFIX = "write:";
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/**
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* The length of the read prefix, in characters.
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*/
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private static final int READ_PREFIX_LENGTH = READ_PREFIX.length();
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/**
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* The length of the write prefix, in characters.
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*/
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private static final int WRITE_PREFIX_LENGTH = WRITE_PREFIX.length();
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/**
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* The length of every tunnel UUID, in characters.
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*/
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private static final int UUID_LENGTH = 36;
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@Override
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protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException {
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handleTunnelRequest(request, response);
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}
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@Override
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protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException {
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handleTunnelRequest(request, response);
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}
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/**
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* Sends an error on the given HTTP response with the given integer error
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* code.
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*
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* @param response The HTTP response to use to send the error.
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* @param code The HTTP status code of the error.
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* @throws ServletException If an error prevents sending of the error
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* code.
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*/
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private void sendError(HttpServletResponse response, int code) throws ServletException {
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try {
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// If response not committed, send error code
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if (!response.isCommitted())
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response.sendError(code);
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}
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catch (IOException ioe) {
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// If unable to send error at all due to I/O problems,
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// rethrow as servlet exception
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throw new ServletException(ioe);
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}
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}
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/**
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* Dispatches every HTTP GET and POST request to the appropriate handler
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* function based on the query string.
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*
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* @param request The HttpServletRequest associated with the GET or POST
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* request received.
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* @param response The HttpServletResponse associated with the GET or POST
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* request received.
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* @throws ServletException If an error occurs while servicing the request.
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*/
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protected void handleTunnelRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException {
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try {
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String query = request.getQueryString();
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if (query == null)
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throw new GuacamoleClientException("No query string provided.");
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// If connect operation, call doConnect() and return tunnel UUID
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// in response.
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if (query.equals("connect")) {
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GuacamoleTunnel tunnel = doConnect(request);
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if (tunnel != null) {
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// Get session
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HttpSession httpSession = request.getSession(true);
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GuacamoleSession session = new GuacamoleSession(httpSession);
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// Attach tunnel to session
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session.attachTunnel(tunnel);
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logger.info("Connection from {} succeeded.", request.getRemoteAddr());
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try {
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// Ensure buggy browsers do not cache response
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response.setHeader("Cache-Control", "no-cache");
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// Send UUID to client
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response.getWriter().print(tunnel.getUUID().toString());
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}
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catch (IOException e) {
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throw new GuacamoleServerException(e);
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}
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}
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// Failed to connect
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else {
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logger.info("Connection from {} failed.", request.getRemoteAddr());
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throw new GuacamoleResourceNotFoundException("No tunnel created.");
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}
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}
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// If read operation, call doRead() with tunnel UUID, ignoring any
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// characters following the tunnel UUID.
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else if(query.startsWith(READ_PREFIX))
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doRead(request, response, query.substring(
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READ_PREFIX_LENGTH,
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READ_PREFIX_LENGTH + UUID_LENGTH));
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// If write operation, call doWrite() with tunnel UUID, ignoring any
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// characters following the tunnel UUID.
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else if(query.startsWith(WRITE_PREFIX))
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doWrite(request, response, query.substring(
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WRITE_PREFIX_LENGTH,
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WRITE_PREFIX_LENGTH + UUID_LENGTH));
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// Otherwise, invalid operation
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else
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throw new GuacamoleClientException("Invalid tunnel operation: " + query);
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}
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// Catch any thrown guacamole exception and attempt to pass within the
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// HTTP response, logging each error appropriately.
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catch (GuacamoleSecurityException e) {
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logger.warn("Authorization failed.", e);
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sendError(response, HttpServletResponse.SC_FORBIDDEN);
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}
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catch (GuacamoleResourceNotFoundException e) {
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logger.debug("Resource not found.", e);
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sendError(response, HttpServletResponse.SC_NOT_FOUND);
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}
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catch (GuacamoleClientException e) {
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logger.warn("Error in client request.", e);
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sendError(response, HttpServletResponse.SC_BAD_REQUEST);
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}
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catch (GuacamoleException e) {
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logger.error("Server error in tunnel", e);
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sendError(response, HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
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}
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}
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/**
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* Called whenever the JavaScript Guacamole client makes a connection
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* request. It it up to the implementor of this function to define what
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* conditions must be met for a tunnel to be configured and returned as a
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* result of this connection request (whether some sort of credentials must
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* be specified, for example).
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*
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* @param request The HttpServletRequest associated with the connection
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* request received. Any parameters specified along with
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* the connection request can be read from this object.
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* @return A newly constructed GuacamoleTunnel if successful,
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* null otherwise.
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* @throws GuacamoleException If an error occurs while constructing the
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* GuacamoleTunnel, or if the conditions
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* required for connection are not met.
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*/
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protected abstract GuacamoleTunnel doConnect(HttpServletRequest request) throws GuacamoleException;
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/**
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* Called whenever the JavaScript Guacamole client makes a read request.
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* This function should in general not be overridden, as it already
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* contains a proper implementation of the read operation.
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*
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* @param request The HttpServletRequest associated with the read request
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* received.
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* @param response The HttpServletResponse associated with the write request
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* received. Any data to be sent to the client in response
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* to the write request should be written to the response
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* body of this HttpServletResponse.
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* @param tunnelUUID The UUID of the tunnel to read from, as specified in
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* the write request. This tunnel must be attached to
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* the Guacamole session.
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* @throws GuacamoleException If an error occurs while handling the read
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* request.
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*/
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protected void doRead(HttpServletRequest request, HttpServletResponse response, String tunnelUUID) throws GuacamoleException {
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HttpSession httpSession = request.getSession(false);
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GuacamoleSession session = new GuacamoleSession(httpSession);
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// Get tunnel, ensure tunnel exists
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GuacamoleTunnel tunnel = session.getTunnel(tunnelUUID);
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if (tunnel == null)
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throw new GuacamoleResourceNotFoundException("No such tunnel.");
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// Ensure tunnel is open
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if (!tunnel.isOpen())
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throw new GuacamoleResourceNotFoundException("Tunnel is closed.");
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// Obtain exclusive read access
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GuacamoleReader reader = tunnel.acquireReader();
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try {
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// Note that although we are sending text, Webkit browsers will
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// buffer 1024 bytes before starting a normal stream if we use
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// anything but application/octet-stream.
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response.setContentType("application/octet-stream");
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response.setHeader("Cache-Control", "no-cache");
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// Get writer for response
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Writer out = new BufferedWriter(new OutputStreamWriter(
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response.getOutputStream(), "UTF-8"));
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// Stream data to response, ensuring output stream is closed
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try {
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// Detach tunnel and throw error if EOF (and we haven't sent any
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// data yet.
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char[] message = reader.read();
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if (message == null)
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throw new GuacamoleResourceNotFoundException("Tunnel reached end of stream.");
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// For all messages, until another stream is ready (we send at least one message)
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do {
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// Get message output bytes
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out.write(message, 0, message.length);
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// Flush if we expect to wait
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if (!reader.available()) {
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out.flush();
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response.flushBuffer();
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}
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// No more messages another stream can take over
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if (tunnel.hasQueuedReaderThreads())
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break;
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} while (tunnel.isOpen() && (message = reader.read()) != null);
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// Close tunnel immediately upon EOF
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if (message == null)
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tunnel.close();
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// End-of-instructions marker
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out.write("0.;");
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out.flush();
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response.flushBuffer();
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}
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// Always close output stream
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finally {
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out.close();
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}
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}
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catch (GuacamoleException e) {
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// Detach and close
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session.detachTunnel(tunnel);
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tunnel.close();
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throw e;
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}
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catch (IOException e) {
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// Log typically frequent I/O error if desired
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logger.debug("Error writing to servlet output stream", e);
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// Detach and close
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session.detachTunnel(tunnel);
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tunnel.close();
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}
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finally {
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tunnel.releaseReader();
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}
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}
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/**
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* Called whenever the JavaScript Guacamole client makes a write request.
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* This function should in general not be overridden, as it already
|
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* contains a proper implementation of the write operation.
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*
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* @param request The HttpServletRequest associated with the write request
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* received. Any data to be written will be specified within
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* the body of this request.
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* @param response The HttpServletResponse associated with the write request
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* received.
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* @param tunnelUUID The UUID of the tunnel to write to, as specified in
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* the write request. This tunnel must be attached to
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* the Guacamole session.
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* @throws GuacamoleException If an error occurs while handling the write
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* request.
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*/
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protected void doWrite(HttpServletRequest request, HttpServletResponse response, String tunnelUUID) throws GuacamoleException {
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HttpSession httpSession = request.getSession(false);
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GuacamoleSession session = new GuacamoleSession(httpSession);
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GuacamoleTunnel tunnel = session.getTunnel(tunnelUUID);
|
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if (tunnel == null)
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throw new GuacamoleResourceNotFoundException("No such tunnel.");
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// We still need to set the content type to avoid the default of
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// text/html, as such a content type would cause some browsers to
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// attempt to parse the result, even though the JavaScript client
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// does not explicitly request such parsing.
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response.setContentType("application/octet-stream");
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response.setHeader("Cache-Control", "no-cache");
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response.setContentLength(0);
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// Send data
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try {
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// Get writer from tunnel
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GuacamoleWriter writer = tunnel.acquireWriter();
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// Get input reader for HTTP stream
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Reader input = new InputStreamReader(
|
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request.getInputStream(), "UTF-8");
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|
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// Transfer data from input stream to tunnel output, ensuring
|
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// input is always closed
|
||||
try {
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|
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// Buffer
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int length;
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char[] buffer = new char[8192];
|
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// Transfer data using buffer
|
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while (tunnel.isOpen() &&
|
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(length = input.read(buffer, 0, buffer.length)) != -1)
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writer.write(buffer, 0, length);
|
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|
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}
|
||||
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// Close input stream in all cases
|
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finally {
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input.close();
|
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}
|
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|
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}
|
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catch (IOException e) {
|
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|
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// Detach and close
|
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session.detachTunnel(tunnel);
|
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tunnel.close();
|
||||
|
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throw new GuacamoleServerException("I/O Error sending data to server: " + e.getMessage(), e);
|
||||
}
|
||||
finally {
|
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tunnel.releaseWriter();
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* \example ExampleTunnelServlet.java
|
||||
*
|
||||
* A basic example demonstrating extending GuacamoleTunnelServlet and
|
||||
* implementing doConnect() to configure the Guacamole connection as
|
||||
* desired.
|
||||
*/
|
||||
|
||||
@@ -0,0 +1,125 @@
|
||||
|
||||
package org.glyptodon.guacamole.servlet;
|
||||
|
||||
/* ***** BEGIN LICENSE BLOCK *****
|
||||
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
|
||||
*
|
||||
* The contents of this file are subject to the Mozilla Public License Version
|
||||
* 1.1 (the "License"); you may not use this file except in compliance with
|
||||
* the License. You may obtain a copy of the License at
|
||||
* http://www.mozilla.org/MPL/
|
||||
*
|
||||
* Software distributed under the License is distributed on an "AS IS" basis,
|
||||
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
||||
* for the specific language governing rights and limitations under the
|
||||
* License.
|
||||
*
|
||||
* The Original Code is guacamole-common.
|
||||
*
|
||||
* The Initial Developer of the Original Code is
|
||||
* Michael Jumper.
|
||||
* Portions created by the Initial Developer are Copyright (C) 2010
|
||||
* the Initial Developer. All Rights Reserved.
|
||||
*
|
||||
* Contributor(s):
|
||||
*
|
||||
* Alternatively, the contents of this file may be used under the terms of
|
||||
* either the GNU General Public License Version 2 or later (the "GPL"), or
|
||||
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
||||
* in which case the provisions of the GPL or the LGPL are applicable instead
|
||||
* of those above. If you wish to allow use of your version of this file only
|
||||
* under the terms of either the GPL or the LGPL, and not to allow others to
|
||||
* use your version of this file under the terms of the MPL, indicate your
|
||||
* decision by deleting the provisions above and replace them with the notice
|
||||
* and other provisions required by the GPL or the LGPL. If you do not delete
|
||||
* the provisions above, a recipient may use your version of this file under
|
||||
* the terms of any one of the MPL, the GPL or the LGPL.
|
||||
*
|
||||
* ***** END LICENSE BLOCK ***** */
|
||||
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
import java.util.concurrent.ConcurrentMap;
|
||||
import javax.servlet.http.HttpSession;
|
||||
import org.glyptodon.guacamole.GuacamoleException;
|
||||
import org.glyptodon.guacamole.GuacamoleSecurityException;
|
||||
import org.glyptodon.guacamole.net.GuacamoleTunnel;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/**
|
||||
* Provides abstract access to the tunnels associated with a Guacamole session.
|
||||
*
|
||||
* @author Michael Jumper
|
||||
*/
|
||||
public class GuacamoleSession {
|
||||
|
||||
/**
|
||||
* Logger for this class.
|
||||
*/
|
||||
private Logger logger = LoggerFactory.getLogger(GuacamoleSession.class);
|
||||
|
||||
/**
|
||||
* Map of all currently attached tunnels, indexed by tunnel UUID.
|
||||
*/
|
||||
private ConcurrentMap<String, GuacamoleTunnel> tunnels;
|
||||
|
||||
/**
|
||||
* Creates a new GuacamoleSession, storing and retrieving tunnels from the
|
||||
* given HttpSession. Note that the true Guacamole session is tied to the
|
||||
* HttpSession provided, thus creating a new GuacamoleSession does not
|
||||
* create a new Guacamole session; it merely creates a new object for
|
||||
* accessing the tunnels of an existing Guacamole session represented by
|
||||
* the provided HttpSession.
|
||||
*
|
||||
* @param session The HttpSession to use as tunnel storage.
|
||||
* @throws GuacamoleException If session is null.
|
||||
*/
|
||||
@SuppressWarnings("unchecked")
|
||||
public GuacamoleSession(HttpSession session) throws GuacamoleException {
|
||||
|
||||
if (session == null)
|
||||
throw new GuacamoleSecurityException("User has no session.");
|
||||
|
||||
synchronized (session) {
|
||||
|
||||
tunnels = (ConcurrentMap<String, GuacamoleTunnel>) session.getAttribute("GUAC_TUNNELS");
|
||||
if (tunnels == null) {
|
||||
tunnels = new ConcurrentHashMap<String, GuacamoleTunnel>();
|
||||
session.setAttribute("GUAC_TUNNELS", tunnels);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Attaches the given tunnel to this GuacamoleSession.
|
||||
* @param tunnel The tunnel to attach to this GucacamoleSession.
|
||||
*/
|
||||
public void attachTunnel(GuacamoleTunnel tunnel) {
|
||||
tunnels.put(tunnel.getUUID().toString(), tunnel);
|
||||
logger.debug("Attached tunnel {}.", tunnel.getUUID());
|
||||
}
|
||||
|
||||
/**
|
||||
* Detaches the given tunnel to this GuacamoleSession.
|
||||
* @param tunnel The tunnel to detach to this GucacamoleSession.
|
||||
*/
|
||||
public void detachTunnel(GuacamoleTunnel tunnel) {
|
||||
tunnels.remove(tunnel.getUUID().toString());
|
||||
logger.debug("Detached tunnel {}.", tunnel.getUUID());
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the tunnel with the given UUID attached to this GuacamoleSession,
|
||||
* if any.
|
||||
*
|
||||
* @param tunnelUUID The UUID of an attached tunnel.
|
||||
* @return The tunnel corresponding to the given UUID, if attached, or null
|
||||
* if no such tunnel is attached.
|
||||
*/
|
||||
public GuacamoleTunnel getTunnel(String tunnelUUID) {
|
||||
return tunnels.get(tunnelUUID);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,7 @@
|
||||
|
||||
/**
|
||||
* Classes which build upon the Java Servlet API, providing an HTTP-based
|
||||
* tunnel and session management.
|
||||
*/
|
||||
package org.glyptodon.guacamole.servlet;
|
||||
|
||||
Reference in New Issue
Block a user