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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You may also need to compile/install libwebsockets from source if the libwebsockets-dev package is outdated.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 Gentoo: 
clone the repo at https://bitbucket.org/mgpagano/ttyd/src/master/ and follow the directions here for creating a local repository.

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:
1.4.4

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)
-a, –url-arg           Allow client to send command line arguments in URL (eg: http://localhost:7681?arg=foo&arg=bar)
-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.

Updated: May 8, 2019 — 4:00 am

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