Script to install wsl-vpnkit with a systemd service for Debian/Ubuntu

wsl-vpnkit.sh

#!/usr/bin/env bash
# -------------------------------------------------------------------------
# wsl-vpnkit install script
# -------------------------------------------------------------------------

# Check if user is root
[ "$(id -u)" != "0" ] && {
    echo "Error: You must be root or use sudo to run this script"
    exit 1
}

export DEBIAN_FRONTEND=noninteractive
unset LANG
export LANG='en_US.UTF-8'
export LC_ALL='C.UTF-8'

# Colors
CSI='\033['
CRED="${CSI}1;31m"
CGREEN="${CSI}1;32m"
CEND="${CSI}0m"

# update package list
apt-get update -qq

# check if a command exist
command_exists() {
    command -v "$@" >/dev/null 2>&1
}

# check if required packages are installed
required_packages="curl tar jq"
for package in $required_packages; do
    if ! command_exists "$package"; then
        apt-get install "$package" -qq >/dev/null 2>&1
    fi
done

_install_dependencies() {
    echo -ne '       Installing dependencies              [..]\r'
    if {
        # install dependencies
        apt-get install iproute2 iptables iputils-ping dnsutils wget -y
    } >>/tmp/wslvpnkit.log 2>&1; then
        echo -ne "       Installing dependencies              [${CGREEN}OK${CEND}]\\r"
        echo -ne '\n'
    else
        echo -e "        Installing dependencies            [${CRED}FAIL${CEND}]"
        echo -e '\n      Please look at /tmp/wslvpnkit.log\n'
        exit 1
    fi
}

create_startup_script() {
    echo -ne '       Creating startup script              [..]\r'
    if {
        cat <<EOF >/usr/local/bin/start-vpn-kit.sh
#!/bin/sh

export WSL_INTEROP=
for socket in $(ls /run/WSL | sort -n); do
   if ss -elx | grep "$socket"; then
      export WSL_INTEROP=/run/WSL/$socket
   else
      rm $socket
   fi
done

# also start wsl-vpnkit
/mnt/c/Windows/system32/wsl.exe -d wsl-vpnkit --cd /app wsl-vpnkit


EOF

        chmod +x /usr/local/bin/start-vpn-kit.sh
    } >>/tmp/wslvpnkit.log 2>&1; then
        echo -ne "       Creating startup script              [${CGREEN}OK${CEND}]\\r"
        echo -ne '\n'
    else
        echo -e "       Creating startup script              [${CRED}FAIL${CEND}]"
        echo -e '\n      Please look at /tmp/wslvpnkit.log\n'
        exit 1
    fi
}

create_systemd_service() {
    echo -ne '       Creating systemd service             [..]\r'
    if {
        cat <<EOF >/lib/systemd/system/wsl-vpnkit.service
[Unit]
Description=wsl-vpnkit
After=network.target

[Service]
# for wsl-vpnkit setup as a distro
ExecStart=/usr/local/bin/start-vpn-kit.sh

Restart=always
KillMode=mixed

[Install]
WantedBy=multi-user.target


EOF
    } >>/tmp/wslvpnkit.log 2>&1; then
        echo -ne "       Creating systemd service             [${CGREEN}OK${CEND}]\\r"
        echo -ne '\n'
    else
        echo -e "        Creating systemd service           [${CRED}FAIL${CEND}]"
        echo -e '\n      Please look at /tmp/wslvpnkit.log\n'
        exit 1
    fi
}

_starting_wsl_vpnkit() {
    echo -ne '       Starting wsl-vpnkit                  [..]\r'
    if {
        # activer le service
        systemctl enable wsl-vpnkit.service

        # démarrer le service
        systemctl start wsl-vpnkit.service
    } >>/tmp/wslvpnkit.log 2>&1; then
        echo -ne "       Starting wsl-vpnkit                  [${CGREEN}OK${CEND}]\\r"
        echo -ne '\n'
    else
        echo -e "        Starting wsl-vpnkit                [${CRED}FAIL${CEND}]"
        echo -e '\n      Please look at /tmp/wslvpnkit.log\n'
        exit 1
    fi
}

###############
# Main
###############

_install_dependencies
create_startup_script
create_systemd_service
_starting_wsl_vpnkit