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X2Go's HTML client makes use of HTML5, JavaScript, and WebSockets to provide graphical access to a remote host with no client-side requirements other than a modern browser. The x2gohtmlclient package, served by a web server, provides the JavaScript front-end. X2gohtmlclient works with the x2gowebrpc and x2gowswrapper packages, which run on the server. Aside from the aforementioned X2Go packages, the server-side requirements include
X2Go provides instructions for configuring the NGINX web server, but you can substitute another server if you prefer. Your operating system distribution likely provides packages containing the dependencies not provided by X2Go.
Client HTML page. This page can be modified or embedded in existing webpage. It has two modes: native client and embedded client. User can use native client if recent version of X2Go client is installed on the system. In this case, the page will generate x2go session file, which will be automatically opened with x2go client. Second mode is to use embedded HTML Client (only supports X2GoKdrive). The HTML page provides user input for the next settings:
X2Go Server address Username Password Command to execute (KDE, GNOME, ICEWM, etc) SSH Proxy (if not specified no proxy will be used) Proxy login Proxy password
The HTML page can be modified to predefine one or more of this settings. Important functions inside of this page should be defined:
function getServer() function getUname() function getPass() function getCommand() function getName() function getProxy() function getProxyUser() function getProxyPass()
The HTML Page to run X2Go client in separate window. By default the session's window is embedded in the start page. User can “detach” the session to separate window using “new window” button. After that session will be shown in the separate window and can be resized, opened in full screen, etc.
WEB styles for HTML pages
Image resources
Communication between HTML page and X2Go HTML Client
Communication between X2Go RPC script and X2Go HTML Client
X2GoKdrive JS client
CGI script for communication between HTML Client and X2Go server. It connects to X2Go server using ssh, starts/resuming sessions, opens SSH tunnels, etc
The application which is connecting TCP sockets of X2GoKdrive agent with web sockets for HTML Client.
JS classes should be compiled in one using script minify.sh. The resulting file x2goclient.js will be placed in subdir “dist”
Build using qmake
$qmake-qt5 && make
Prerequements: Web Browser with support for CGI and Web sockets (for example nginx).
Example of nginx configuration (in this case with fcgiwrap https://www.nginx.com/resources/wiki/start/topics/examples/fcgiwrap/)
/etc/nginx/sites-available/<your host>-ssl:
server { listen 443 ssl; server_name your_host; ssl_certificate <your SSL cert>; ssl_certificate_key <your SSL cert key>; ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384; ssl_protocols TLSv1.2; ssl_prefer_server_ciphers off; ssl_session_timeout 5m; ssl_session_cache builtin:1000 shared:SSL:10m; ssl_session_tickets off; root /var/www/html; proxy_read_timeout 300; location /assets/ { add_header Strict-Transport-Security "max-age=31536000"; add_header Content-Security-Policy "default-src 'self' 'unsafe-inline' data: blob: ws: wss:; script-src 'self' 'unsafe-inline' add_header Feature-Policy "vibrate 'none' ; microphone 'none' ; camera 'none' ; gyroscope 'none' ; magnetometer 'none' ; geolocation 'none' ; midi 'self' ; notifications 'self' ; push 'self' ; sync-xhr 'self'"; add_header Referrer-Policy "same-origin"; add_header X-Content-Type-Options "nosniff"; add_header X-Frame-Options "SAMEORIGIN"; } location ~* \.(pl|cgi)$ { gzip off; include /etc/nginx/fastcgi_params; fastcgi_pass unix:/var/run/fcgiwrap.socket; } location ~ ^/x2gows/(.*)$ { proxy_pass https://127.0.0.1:$1; proxy_set_header Upgrade $http_upgrade; proxy_set_header Connection "upgrade"; proxy_http_version 1.1; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header Host $http_host; proxy_intercept_errors on; proxy_redirect off; proxy_cache_bypass $http_upgrade; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-NginX-Proxy true; proxy_ssl_session_reuse off; } }
X2Go HTML client files:
<WEB ROOT>/assets/x2go-plugin/ CSS/x2gostyle.css IMG/*.png IMG/x2gobg.svg JS/x2goclient.js RPC/x2gorpc.cgi index.html x2gokdriveclient.html
This location can be changed, in this case the changes should be also done in the WEB Server configuration file and in index.html file:
var RPC_path="/assets/x2go-plugin/RPC/x2gorpc.cgi"; var asset_path="/assets/x2go-plugin/IMG/";
x2gorpc.cgi should be executable
install x2gowswrapper to /usr/bin
x2gowswarpper configuration:
/etc/x2go/x2gows/x2gows.options
ws_proto=wss ssl_cert=<your SSL cert> ssl_key=<your SSL cert key> ssl_only=true log_dir=/var/log/x2gows
the SSL key should be same which used for WEB server.
Because x2gowswrapper is started from CGI, be sure that config and SSL Certs are accessible for web server user (www-data in debian)
create log directory for x2gowswarpper:
#mkdir /var/log/x2gows #chown www-data /var/log/x2gows
to use x2go HTML client open in web browser:
https://<your host>/assets/x2go-plugin/