ttyd - Share your terminal over the web

ttyd is a simple command-line tool for sharing terminal over the web, inspired by GoTTY.

Features

• Built on top of Libwebsockets with C for speed
• Fully-featured terminal based on Xterm.js with CJK and IME support
• Graphical ZMODEM integration with lrzsz support
• SSL support based on OpenSSL
• Run any custom command with options
• Basic authentication support and many other custom options
• Cross platform: macOS, Linux, FreeBSD/OpenBSD, OpenWrt/LEDE, Windows

Installation

Install on macOS

Install with homebrew:

brew install ttyd

Install on Linux

• Binary version: download from the releases page.

• Build from source (debian/ubuntu):

  sudo apt-get install cmake g++ pkg-config git vim-common libwebsockets-dev libjson-c-dev libssl-dev
  git clone https://github.com/tsl0922/ttyd.git
  cd ttyd && mkdir build && cd build
  cmake ..
  make && make install

  You may also need to compile/install libwebsockets from source if the libwebsockets-dev package is outdated.

Install on Windows

ttyd can be built with MSYS2 on windows, The build instructions is here.

NOTE: Native windows console programs may not work correctly due to pty incompatibility issues. As a workaround, you can use winpty as a wrapper to invoke the windows program, eg: ttyd winpty cmd.

Install on OpenWrt/LEDE

LEDE 17.01.0 and later:

opkg install ttyd

You may want to compile it manually.

Usage

Command-line Options

ttyd is a tool for sharing terminal over the web

USAGE:
    ttyd [options] <command> [<arguments...>]

VERSION:
    1.4.2

OPTIONS:
    -p, --port              Port to listen (default: 7681, use `0` for random port)
    -i, --interface         Network interface to bind (eg: eth0), or UNIX domain socket path (eg: /var/run/ttyd.sock)
    -c, --credential        Credential for Basic Authentication (format: username:password)
    -u, --uid               User id to run with
    -g, --gid               Group id to run with
    -s, --signal            Signal to send to the command when exit it (default: 1, SIGHUP)
    -r, --reconnect         Time to reconnect for the client in seconds (default: 10)
    -R, --readonly          Do not allow clients to write to the TTY
    -t, --client-option     Send option to client (format: key=value), repeat to add more options
    -T, --terminal-type     Terminal type to report, default: xterm-256color
    -O, --check-origin      Do not allow websocket connection from different origin
    -m, --max-clients       Maximum clients to support (default: 0, no limit)
    -o, --once              Accept only one client and exit on disconnection
    -B, --browser           Open terminal with the default system browser
    -I, --index             Custom index.html path
    -6, --ipv6              Enable IPv6 support
    -S, --ssl               Enable SSL
    -C, --ssl-cert          SSL certificate file path
    -K, --ssl-key           SSL key file path
    -A, --ssl-ca            SSL CA file path for client certificate verification
    -d, --debug             Set log level (default: 7)
    -v, --version           Print the version and exit
    -h, --help              Print this text and exit

Visit https://github.com/tsl0922/ttyd to get more information and report bugs.

Example Usage

ttyd starts web server at port 7681 by default, you can use the -p option to change it, the command will be started with arguments as options. For example, run:

ttyd -p 8080 bash -x

Then open http://localhost:8080 with a browser, you will get a bash shell with debug mode enabled.

More Examples:

• If you want to login with your system accounts on the web browser, run ttyd login.
• You can even run a none shell command like vim, try: ttyd vim, the web browser will show you a vim editor.
• Sharing single process with multiple clients: ttyd tmux new -A -s ttyd vim, run tmux new -A -s ttyd to connect to the tmux session from terminal.

Browser Support

Modern browsers, See Browser Support.

SSL how-to

Generate SSL CA and self signed server/client certificates:

# CA certificate (FQDN must be different from server/client)
openssl genrsa -out ca.key 2048
openssl req -new -x509 -days 365 -key ca.key -subj "/C=CN/ST=GD/L=SZ/O=Acme, Inc./CN=Acme Root CA" -out ca.crt

# server certificate (for multiple domains, change subjectAltName to: DNS:example.com,DNS:www.example.com)
openssl req -newkey rsa:2048 -nodes -keyout server.key -subj "/C=CN/ST=GD/L=SZ/O=Acme, Inc./CN=localhost" -out server.csr
openssl x509 -req -extfile <(printf "subjectAltName=DNS:localhost") -days 365 -in server.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out server.crt

# client certificate (the p12/pem format may be useful for some clients)
openssl req -newkey rsa:2048 -nodes -keyout client.key -subj "/C=CN/ST=GD/L=SZ/O=Acme, Inc./CN=client" -out client.csr
openssl x509 -req -days 365 -in client.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out client.crt
openssl pkcs12 -export -clcerts -in client.crt -inkey client.key -out client.p12
openssl pkcs12 -in client.p12 -out client.pem -clcerts

Then start ttyd:

ttyd --ssl --ssl-cert server.crt --ssl-key server.key --ssl-ca ca.crt bash

You may want to test the client certificate verification with curl:

curl --insecure --cert client.p12[:password] -v https://localhost:7681

If you don't want to enable client certificate verification, remove the --ssl-ca option.

Docker and ttyd

Docker containers are jailed environments which are more secure, this is useful for protecting the host system, you may use ttyd with docker like this:

• Sharing single docker container with multiple clients: docker run -it --rm -p 7681:7681 tsl0922/ttyd.
• Creating new docker container for each client: ttyd docker run -it --rm ubuntu.

Credits

• GoTTY: ttyd is a port of GoTTY to C language with many improvements.
• Libwebsockets: is used to build the websocket server.
• Xterm.js: is used to run the terminal emulator on the web, hterm is used previously.