Web-based Terminal Emulator

This program allows you to use terminal in the browser. Simply run the program and give it the command to execute when users connect via the browser. Interestingly, it allows others to view your interactive sessions as well. This could be useful to provide remote support and/or help. You can use the program to run any command line programs, such as bash, htop, vi, ssh. This following screenshot shows that six interactive session running by the server.

To use the program, you need to provide a TLS cert. You can request a free Let’s Encrypt cert or use a self-signed cert. The program currently does not support user authentication. Therefore, do not run it in untrusted networks or leave it running. A probably safe use of the program is to run ssh. Please ensure that you do not automatically login to the ssh server (e.g., via key authentication).

AGAIN, Do NOT run this in an untrusted network. You will expose your shell to anyone that can access your network and Do NOT leave the server running.

This program is written in the go programming language, using the Gin web framework, gorilla/websocket, pty, and the wonderful xterm.js! The workflow is simple, the client will initiate a terminal window (xterm.js) and create a websocket with the server, which relays the data between pty and xterm. You can customize the look and feel of the HTML pages by editing files under the assets directory.

Installation

1. Install the go compiler.

2. Download the release and unzip it, or clone the repo

   git clone https://github.com/syssecfsu/web_terminal.git

3. Go to the tls directory and create a self-signed cert

   # Generate a private key for a curve

   openssl ecparam -name prime256v1 -genkey -noout -out private-key.pem

   # Create a self-signed certificate

   openssl req -new -x509 -key private-key.pem -out cert.pem -days 360

4. Return to the root directory of the source code and build the program

   go build .

5. Start the server and give it the command to run. The server listens on 8080, for example:

   ./web_terminal htop or

   ./web_terminal ssh <your_server_ip> -l <user_name>

6. Connect to the server, for example

   https://your_ip_address:8080

The program has been tested on Linux, WSL2, Raspberry Pi 3B (Debian), and MacOSX using Google Chrome, Firefox, and Safari.

An Screencast _{featuring an older version of web_terminal}

Here is a screencast for sshing into Raspberry Pi running pi-hole (./web_terminal ssh 192.168.1.2 -l pi, web_terminal runs in a WSL2 VM on Windows):