An easy to use installer for Tailscale on portable game consoles running Knulli OS.

knulli_tailscale_installer.sh

#!/bin/bash

SCRIPT_VERSION="1.3"
INSTALL_DIR="/userdata/system/tailscale"
UA_STRING="Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:40.0) Gecko/20100101 Firefox/40.0"

# Function to check device compatibility
function device_check {
	# Get OS_NAME variable from /etc/os-release
	local os_name=$(grep "^OS_NAME" /etc/os-release | awk -F'=' '{print $2}' | tr -d '"')
	
	if [[ "$os_name" == "knulli" ]]; then
		return 0
	fi
	
	local confirmation
	clear
	echo "          __        ___    ____  _   _ ___ _   _  ____    _ "
	echo "          \ \      / / \  |  _ \| \ | |_ _| \ | |/ ___|  | |"
	echo "           \ \ /\ / / _ \ | |_) |  \| || ||  \| | |  _   | |"
	echo "            \ V  V / ___ \|  _ <| |\  || || |\  | |_| |  |_|"
	echo "             \_/\_/_/   \_\_| \_\_| \_|___|_| \_|\____|  (_)"
	echo "                                                            "
	echo "This script was designed to be used on handheld game consoles running the "
	echo "Knulli operating system. It appears your device is not running Knulli OS."
	echo ""
	echo "If you believe this is a mistake and wish to continue using this script,"
	echo "type \"continue anyway\". To abort and exit the script, press Enter."
	echo ""
	echo -n "> "
	read confirmation
	
	if [[ "$confirmation" == "continue anyway" ]]; then
		return 0
	fi
	
	echo -e "Aborted!\n"
	
	exit 0
}

# Function to display an error message that can either be manually dismissed 
# by pressing Enter, or automatically after a certain amount of time (in seconds) 
# has passed (amount is given as the second argument in the function call).
#
# Usage: show_error <error_message_string> [timeout]
function show_error {
	if [[ ! -z $1 ]]; then
		echo -e "\nERROR: $1"
	fi
	
	if [[ $2 > 0 ]]; then
		sleep $2
	else
		echo -e "\nPress Enter to return to the main menu..."
		read
	fi
	
	return 0
}

# Function that creates a service file for the Tailscale daemon to run at system startup
function ts_create_service {
	echo -n "Installing service... "
	mkdir -p "/userdata/system/services"
	cat <<EOF > "/userdata/system/services/tailscale"
#!/bin/sh

RETVAL=0

start() {
	echo "Starting tailscaled service..."
	start-stop-daemon -S -b -q -x ${INSTALL_DIR}/tailscaled -- --state=${INSTALL_DIR}/tailscaled.state
	RETVAL=\$?
	echo "Done!"
	
	return \$RETVAL
}

stop() {
	echo -n "Shutting down tailscaled service: "
	start-stop-daemon -K -q -n tailscaled
	RETVAL=\$?
	echo "Done!"

	return \$RETVAL
}

restart() {
	stop
	start
}

reload() {
	echo -n "Reloading tailscaled service: "
	kill -HUP \$(pidof tailscaled)
	RETVAL=\$?
	echo "Done!"

	return \$RETVAL
}

case "\$1" in
	start)
  		start
	;;
	stop)
  		stop
	;;
	restart)
  		restart
	;;
	reload)
  		reload
	;;
  	*)
		echo "Usage: \$0 {start|stop|restart|reload}"
		exit 1
esac
EOF
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
		show_error "Failed to create service file!"
		return 5
	else
		echo "OK!"
	fi
	chmod +x "/userdata/system/services/tailscale"
	return 0;
}

# Function to get the latest version of Tailscale for ARM64 from Tailscale's
# official package repository: https://pkgs.tailscale.com/stable/
function ts_get_latest_version {
	# Fetch the HTML page that lists the stable packages
	local url="https://pkgs.tailscale.com/stable/"
	local page=$(curl -s "$url")

	# Extract the version numbers from the links
	local versions=$(echo "$page" | grep -oP 'tailscale_\d+\.\d+\.\d+_arm64\.tgz' | sed 's/tailscale_//g' | sed 's/_arm64.tgz//g')

	# Find the latest version
	local latest_version=$(echo "$versions" | sort -V | tail -n 1)
	
	echo "$latest_version"
	return 0
}

# Function to download the latest version of Tailscale and extract the package 
# into the installation directory.
function ts_install_package {
	echo -n "Downloading latest version... "
	local latest_version=$(ts_get_latest_version)
	local tmp_download="/tmp/tailscale_${latest_version}_arm64.tgz"
	wget -q --referer "https://pkgs.tailscale.com/" --user-agent "${UA_STRING}" -O "${tmp_download}" "https://pkgs.tailscale.com/stable/tailscale_${latest_version}_arm64.tgz"
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
		show_error "Failed to download the latest version of Tailscale!"
		rm -f "${tmp_download}"								# downloaded package file
		return 2
	else
		echo "OK!"
	fi
	
	# Extract package contents in /tmp because it contains a directory named 
	# after the current version, which we don't want
	echo -n "Extracting package... "
	tar -xvzf "${tmp_download}" -C "/tmp/" > /dev/null
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
		show_error "Failed to extract the package!"
		rm -f "${tmp_download}"								# downloaded package file
		rm -rf "/tmp/tailscale_${latest_version}_arm64/"	# extracted package contents
		return 3
	else
		echo "OK!"
	fi
	
	# Copy extracted files from the package to the installation directory
	echo -n "Installing package... "
	mkdir -p "${INSTALL_DIR}"
	rsync -aq --remove-source-files "/tmp/tailscale_${latest_version}_arm64/" "${INSTALL_DIR}/"	
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
		show_error "Failed to install the package!"
		rm -f "${tmp_download}"								# downloaded package file
		rm -rf "/tmp/tailscale_${latest_version}_arm64/"	# extracted package contents
		rm -rf "${INSTALL_DIR}/"							# installation directory
		return 4
	else
		echo "OK!"
	fi
	
	# Clean up downloaded package after installation
	echo -n "Cleaning up... "
	rm -f "${tmp_download}"
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
	else
		echo "OK!"
	fi
	
	# Make the "tailscale" and "tailscaled" binaries executable
	chmod +x "${INSTALL_DIR}/tailscale"
	chmod +x "${INSTALL_DIR}/tailscaled"
}

# Menu option: Install Tailscale on this device
#
# This function starts the installation process for Tailscale and guides the user
# through the initial setup process.
function ts_install {
	echo -n "Checking for existing Tailscale installation... "
	if [[ -d "${INSTALL_DIR}" || -e "/userdata/system/services/tailscale" ]]; then
		echo "FAIL!"
		echo "Tailscale already appears to be installed! If you previously tried to "
		echo "install Tailscale and the process was unsuccessful, first uninstall it "
		echo "by choosing option 3 in the main menu, then retry the installation."
		echo ""
		echo "To update an existing installation, choose option 2 from the main menu."
		echo ""
		echo "Press Enter to return to the main menu..."
		read
		return 1
	else
		echo "OK!"
	fi
	
	# Call ts_install_package and abort installation on failure
	ts_install_package
	local ret=$?
	if [[ $ret -ne 0 ]]; then 
		return $ret
	fi
	
	# Call ts_create_service and abort installation on failure
	ts_create_service
	local ret=$?
	if [[ $ret -ne 0 ]]; then
		rm -rf "${INSTALL_DIR}/"
		return $ret
	fi
	
	echo ""
	echo "Tailscale installed successfully!"
	echo "The installation directory is \"${INSTALL_DIR}\"."
	echo "If you need to make changes to your Tailscale configuration or reauthenticate, "
	echo "you will need to navigate to this directory and run the \"tailscale\" binary."
	
	# Setup: Step 1 - Service activation
	echo ""
	echo "On your console, open the Main Menu and navigate to System Settings > Services, "
	echo "and enable \"tailscale\" from the list of services."
	echo ""
	echo -n "Once you're done, press Enter to continue to the setup..."
	read
	
	# Setup: Step 2 - Authenticate into Tailscale
	echo ""
	echo "A URL will be shown below that you need to visit in your browser in order to "
	echo "add your game console to the list of devices in your Tailscale account. If you "
	echo "don't already have an account, you can create one for free after visiting the "
	echo "link."
	${INSTALL_DIR}/tailscale up
	if [[ $? -ne 0 ]]; then 
		echo "Something went wrong during the setup!"
		echo "Please manually navigate to ${INSTALL_DIR} and run"
		echo "\"./tailscale up\" to try authenticating again."
		echo ""
		echo "Press Enter to return to the main menu..."
		read
		return 6
	else
		echo "Setup complete!"
		sleep 5
	fi
	
	return 0
}

# Menu option: Uninstall Tailscale
#
# This function uninstalls Tailscale from the device.
# NOTE: On failures, this function doesn't exit and proceeds regardless. This
#		has been done in order to allow the user to clean up after broken 
#		installation attempts.
function ts_uninstall {
	# Stop the Tailscale daemon service or kill its process
	if [[ -e "/userdata/system/services/tailscale" ]]; then
		/userdata/system/services/tailscale stop
		if [[ $? -ne 0 ]]; then 
			echo -n "Killing tailscaled processes... "
			killall -qw tailscaled
			echo "OK!"
		fi
	else
		echo -n "Killing tailscaled processes... "
		killall -qw tailscaled
		echo "OK!"
	fi
	
	# Delete service file from "/userdata/system/services/"
	echo -n "Removing service file... "
	rm -f "/userdata/system/services/tailscale"
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
	else
		echo "OK!"
	fi
	
	# Delete Tailscale's install folder from "/userdata/system/"
	echo -n "Removing program files... "
	rm -rf "${INSTALL_DIR}"
	if [[ $? -ne 0 ]]; then 
		echo "FAIL!"
	else
		echo "OK!"
	fi
	echo ""
	echo "Tailscale has been uninstalled!"
	sleep 5
	return 0
}

# Menu option: Update the existing Tailscale installation
#
# This function installs the latest version of Tailscale on top of the old
# one's files. This ensures that the session located in the installation
# folder is not lost and the user doesn't need to reauthenticate.
function ts_update {
	echo -n "Checking for existing Tailscale installation... "
	if [[ ! -d "${INSTALL_DIR}" || ! -e "/userdata/system/services/tailscale" ]]; then
		echo "FAIL!"
		echo "Tailscale does not appear to be installed! If you previously tried to "
		echo "install Tailscale and the process was unsuccessful, first uninstall it "
		echo "by choosing option 3 in the main menu, then retry the installation."
		echo ""
		echo "Press Enter to return to the main menu..."
		read
		return 1
	else
		echo "OK!"
	fi

	# Stop the Tailscale daemon service or kill its process
	/userdata/system/services/tailscale stop
	if [[ $? -ne 0 ]]; then 
		echo -n "Killing tailscaled processes... "
		killall -qw tailscaled
		echo "OK!"
	fi
	
	# Call ts_install_package and abort installation on failure
	ts_install_package
	local ret=$?
	if [[ $ret -ne 0 ]]; then 
		return $ret
	fi
	
	# Restart the Tailscale daemon service
	/userdata/system/services/tailscale start
	
	echo ""
	echo "Update complete!"
	sleep 5
	return 0
}

function main {
	device_check

	local choice
	
	while true; do
		clear
		echo "  _  __            _ _ _   _____     _ _               _      "
		echo " | |/ /_ __  _   _| | (_) |_   _|_ _(_) |___  ___ __ _| | ___ "
		echo " | ' /| '_ \| | | | | | |   | |/ _\` | | / __|/ __/ _\` | |/ _ \\"
		echo " | . \| | | | |_| | | | |   | | (_| | | \__ \ (_| (_| | |  __/"
		echo " |_|\_\_| |_|\__,_|_|_|_|   |_|\__,_|_|_|___/\___\__,_|_|\___|"
		echo "             ___           _        _ _                       "
		echo "            |_ _|_ __  ___| |_ __ _| | | ___ _ __             "
		echo "             | || '_ \/ __| __/ _\` | | |/ _ \ '__|            "
		echo "             | || | | \__ \ || (_| | | |  __/ |               "
		echo "            |___|_| |_|___/\__\__,_|_|_|\___|_|               "
		echo "                                                              "
		echo "Developed by Kowalski7				Version: $SCRIPT_VERSION"
		echo ""
		echo "Choose an action to perform:"
		echo "1. Install Tailscale on this device"
		echo "2. Update the existing Tailscale installation"
		echo "3. Uninstall Tailscale"
		echo ""
		echo "0. Exit"
		echo ""
		echo -n "> "
		read choice
		echo ""
		
		case "$choice" in
			1)
				ts_install
				;;
			2)
				ts_update
				;;
			3)
				ts_uninstall
				;;
			0)
				break
				;;
			*)
				echo "Invalid option! Try again."
				sleep 2
				;;
		esac
	done
	
	echo -e "Goodbye!\n"
	
	exit 0
}

main