#!/usr/bin/env bash
# PiVPN: Trivial OpenVPN setup and configuration
# Easiest setup and mangement of OpenVPN on Raspberry Pi
# http://pivpn.io
# Heavily adapted from the pi-hole.net project and...
# https://github.com/StarshipEngineer/OpenVPN-Setup/
#
# Install with this command (from your Pi):
#
# curl -L https://install.pivpn.io | bash
# Make sure you have `curl` installed
set -e

######## VARIABLES #########
setupVars=/etc/pivpn/setupVars.conf
useUpdateVars=false

### PKG Vars ###
PKG_MANAGER="apt-get"
PKG_CACHE="/var/lib/apt/lists/"
UPDATE_PKG_CACHE="${PKG_MANAGER} update"
PKG_INSTALL="${PKG_MANAGER} --yes --no-install-recommends install"
PKG_COUNT="${PKG_MANAGER} -s -o Debug::NoLocking=true upgrade | grep -c ^Inst || true"
PIVPN_DEPS=(openvpn git tar wget grep iptables-persistent dnsutils expect whiptail net-tools)
###          ###

pivpnGitUrl="https://github.com/pivpn/pivpn.git"
pivpnVersionHash="8e3a95152412a9d35b67d51bfc80379350815252"
pivpnFilesDir="/etc/.pivpn"
easyrsaVer="3.0.6"
easyrsaRel="https://github.com/OpenVPN/easy-rsa/releases/download/v${easyrsaVer}/EasyRSA-unix-v${easyrsaVer}.tgz"

# Raspbian's unattended-upgrades package downloads Debian's config, so this is the link for the proper config 
UNATTUPG_RELEASE="1.9"
UNATTUPG_CONFIG="https://github.com/mvo5/unattended-upgrades/archive/${UNATTUPG_RELEASE}.tar.gz"

# Find the rows and columns. Will default to 80x24 if it can not be detected.
screen_size=$(stty size 2>/dev/null || echo 24 80)
rows=$(echo $screen_size | awk '{print $1}')
columns=$(echo $screen_size | awk '{print $2}')

# Divide by two so the dialogs take up half of the screen, which looks nice.
r=$(( rows / 2 ))
c=$(( columns / 2 ))
# Unless the screen is tiny
r=$(( r < 20 ? 20 : r ))
c=$(( c < 70 ? 70 : c ))

######## Undocumented Flags. Shhh ########
skipSpaceCheck=false
reconfigure=false
runUnattended=false

# Find IP used to route to outside world

IPv4dev=$(ip route get 8.8.8.8 | awk '{for(i=1;i<=NF;i++)if($i~/dev/)print $(i+1)}')
IPv4addr=$(ip route get 8.8.8.8| awk '{print $7}')
IPv4gw=$(ip route get 8.8.8.8 | awk '{print $3}')
IPv4dns=8.8.8.8

availableInterfaces=$(ip -o link | grep "state UP" | awk '{print $2}' | cut -d':' -f1 | cut -d'@' -f1)
dhcpcdFile=/etc/dhcpcd.conf

# Next see if we are on a tested and supported OS
function noOS_Support() {
    echo "INVALID OS DETECTED"
    exit 1
}

function maybeOS_Support() {
    echo "OS not officially supported. Continuing."
}

# Compatibility
distro_check() {
    # if lsb_release command is on their system
    if hash lsb_release 2>/dev/null; then

        PLAT=$(lsb_release -si)
        OSCN=$(lsb_release -sc) # We want this to be trusty xenial or jessie

    else # else get info from os-release

        source /etc/os-release
        PLAT=$(awk '{print $1}' <<< "$NAME")
        VER="$VERSION_ID"
        declare -A VER_MAP=(["9"]="stretch" ["8"]="jessie" ["18.04"]="bionic" ["16.04"]="xenial" ["14.04"]="trusty")
        OSCN=${VER_MAP["${VER}"]}
    fi

    if [[ ${OSCN} != "bionic" ]]; then
        PIVPN_DEPS+=(dhcpcd5)
    fi

    case ${PLAT} in
        Ubuntu|Raspbian|Debian|Devuan)
        case ${OSCN} in
            trusty|xenial|jessie|stretch)
            ;;
            *)
            #maybeOS_Support
            ;;
        esac
        ;;
        *)
        noOS_Support
        ;;
    esac

    echo "${PLAT}" > /tmp/DET_PLATFORM
}

####### FUNCTIONS ##########
spinner()
{
    local pid=$1
    local delay=0.50
    local spinstr='/-\|'
    while [ "$(ps a | awk '{print $1}' | grep "${pid}")" ]; do
        local temp=${spinstr#?}
        printf " [%c]  " "${spinstr}"
        local spinstr=${temp}${spinstr%"$temp"}
        sleep ${delay}
        printf "\b\b\b\b\b\b"
    done
    printf "    \b\b\b\b"
}

welcomeDialogs() {
    # Skip welcome dialogs
    echo "Skipping welcome dialogs..."
}

chooseUser() {
    echo "pivpn" > /tmp/pivpnUSR
}

verifyFreeDiskSpace() {
    # We've got plenty of disk space on the SD card
    echo "Skipping disk space check..."
}


chooseInterface() {
    # We use the ethernet port
    pivpnInterface="eth0"
    echo ${pivpnInterface} > /tmp/pivpnINT
}

avoidStaticIPv4Ubuntu() {
    # Not ubuntu...
    echo "We aren't Ubuntu (probably)..."
}

setDHCPCD() {
    # Append these lines to dhcpcd.conf to enable a static IP
    echo "interface ${pivpnInterface}
    static ip_address=${IPv4addr}
    static routers=${IPv4gw}
    static domain_name_servers=${IPv4dns}" | $SUDO tee -a ${dhcpcdFile} >/dev/null
}

setStaticIPv4() {
    # Tries to set the IPv4 address
    if [[ -f /etc/dhcpcd.conf ]]; then
        if grep -q "${IPv4addr}" ${dhcpcdFile}; then
            echo "::: Static IP already configured."
        else
            setDHCPCD
            $SUDO ip addr replace dev "${pivpnInterface}" "${IPv4addr}"
            echo ":::"
            echo "::: Setting IP to ${IPv4addr}.  You may need to restart after the install is complete."
            echo ":::"
        fi
    else
        echo "::: Critical: Unable to locate configuration file to set static IPv4 address!"
        exit 1
    fi
}

function valid_ip()
{
    local  ip=$1
    local  stat=1

    if [[ $ip =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
        OIFS=$IFS
        IFS='.'
        ip=($ip)
        IFS=$OIFS
        [[ ${ip[0]} -le 255 && ${ip[1]} -le 255 \
        && ${ip[2]} -le 255 && ${ip[3]} -le 255 ]]
        stat=$?
    fi
    return $stat
}

#Call this function to use a regex to check user input for a valid custom domain
function valid_domain()
{
  local domain=$1
  local stat=1

  if [[ $domain =~ ^[a-zA-Z0-9][a-zA-Z0-9-]{1,61}\.[a-zA-Z]{2,}$ ]]; then
    stat=$?
  fi
  return $stat
}

installScripts() {
    # Install the scripts from /etc/.pivpn to their various locations
    $SUDO echo ":::"
    $SUDO echo -n "::: Installing scripts to /opt/pivpn..."
    if [ ! -d /opt/pivpn ]; then
        $SUDO mkdir /opt/pivpn
        $SUDO chown "$pivpnUser":root /opt/pivpn
        $SUDO chmod u+srwx /opt/pivpn
    fi
    $SUDO cp /etc/.pivpn/scripts/makeOVPN.sh /opt/pivpn/makeOVPN.sh
    $SUDO cp /etc/.pivpn/scripts/clientStat.sh /opt/pivpn/clientStat.sh
    $SUDO cp /etc/.pivpn/scripts/listOVPN.sh /opt/pivpn/listOVPN.sh
    $SUDO cp /etc/.pivpn/scripts/removeOVPN.sh /opt/pivpn/removeOVPN.sh
    $SUDO cp /etc/.pivpn/scripts/uninstall.sh /opt/pivpn/uninstall.sh
    $SUDO cp /etc/.pivpn/scripts/pivpnDebug.sh /opt/pivpn/pivpnDebug.sh
    $SUDO chmod 0755 /opt/pivpn/{makeOVPN,clientStat,listOVPN,removeOVPN,uninstall,pivpnDebug}.sh
    $SUDO cp /etc/.pivpn/pivpn /usr/local/bin/pivpn
    $SUDO chmod 0755 /usr/local/bin/pivpn
    $SUDO cp /etc/.pivpn/scripts/bash-completion /etc/bash_completion.d/pivpn
    . /etc/bash_completion.d/pivpn
    # Copy interface setting for debug
    $SUDO cp /tmp/pivpnINT /etc/pivpn/pivpnINTERFACE

    $SUDO echo " done."
}

package_check_install() {
    dpkg-query -W -f='${Status}' "${1}" 2>/dev/null | grep -c "ok installed" || ${PKG_INSTALL} "${1}"
}

addSoftwareRepo() {
  # Add the official OpenVPN repo for distros that don't have the latest version in their default repos
  case ${PLAT} in
    Ubuntu|Debian|Devuan)
      case ${OSCN} in
        trusty|xenial|wheezy|jessie)
          wget -qO- https://swupdate.openvpn.net/repos/repo-public.gpg | $SUDO apt-key add -
          echo "deb http://build.openvpn.net/debian/openvpn/stable $OSCN main" | $SUDO tee /etc/apt/sources.list.d/swupdate.openvpn.net.list > /dev/null
          echo -n "::: Adding OpenVPN repo for $PLAT $OSCN ..."
          $SUDO apt-get -qq update & spinner $!
          echo " done!"
          ;;
      esac
      ;;
  esac
}

update_package_cache() {
  #Running apt-get update/upgrade with minimal output can cause some issues with
  #requiring user input

  #Check to see if apt-get update has already been run today
  #it needs to have been run at least once on new installs!
  timestamp=$(stat -c %Y ${PKG_CACHE})
  timestampAsDate=$(date -d @"${timestamp}" "+%b %e")
  today=$(date "+%b %e")


  if [ ! "${today}" == "${timestampAsDate}" ]; then
    #update package lists
    echo ":::"
    echo -n "::: ${PKG_MANAGER} update has not been run today. Running now..."
    $SUDO ${UPDATE_PKG_CACHE} &> /dev/null
    echo " done!"
  fi
}

notify_package_updates_available() {
  # Let user know if they have outdated packages on their system and
  # advise them to run a package update at soonest possible.
  echo ":::"
  echo -n "::: Checking ${PKG_MANAGER} for upgraded packages...."
  updatesToInstall=$(eval "${PKG_COUNT}")
  echo " done!"
  echo ":::"
  if [[ ${updatesToInstall} -eq "0" ]]; then
    echo "::: Your system is up to date! Continuing with PiVPN installation..."
  else
    echo "::: There are ${updatesToInstall} updates available for your system!"
    echo "::: We recommend you update your OS after installing PiVPN! "
    echo ":::"
  fi
}

install_dependent_packages() {
    # Install packages passed in via argument array
    # No spinner - conflicts with set -e
    declare -a argArray1=("${!1}")

    echo iptables-persistent iptables-persistent/autosave_v4 boolean true | $SUDO debconf-set-selections
    echo iptables-persistent iptables-persistent/autosave_v6 boolean false | $SUDO debconf-set-selections

    # Add support for https repositories if there are any that use it otherwise the installation will silently fail
    if grep -q https /etc/apt/sources.list; then
        PIVPN_DEPS+=("apt-transport-https")
    fi

    #if command -v debconf-apt-progress &> /dev/null; then
    #    $SUDO debconf-apt-progress -- ${PKG_INSTALL} "${argArray1[@]}"
    #else
    #    for i in "${argArray1[@]}"; do
    #        echo -n ":::    Checking for $i..."
    #        $SUDO package_check_install "${i}" &> /dev/null
    #        echo " installed!"
    #    done
    #fi

    # myNode - Install all dependent packages without GUI
    for i in "${argArray1[@]}"; do
        echo -n ":::    Checking for $i..."
        $SUDO package_check_install "${i}" &> /dev/null
        echo " installed!"
    done
}

unattendedUpgrades() {
    # Enable unattended upgrades
    #UNATTUPG="unattended-upgrades"
    #whiptail --msgbox --backtitle "Security Updates" --title "Unattended Upgrades" "Since this server will have at least one port open to the internet, it is recommended you enable unattended-upgrades.\nThis feature will check daily for security package updates only and apply them when necessary.\nIt will NOT automatically reboot the server so to fully apply some updates you should periodically reboot." ${r} ${c}
    #if (whiptail --backtitle "Security Updates" --title "Unattended Upgrades" --yesno "Do you want to enable unattended upgrades of security patches to this server?" ${r} ${c}) then
    #    UNATTUPG="unattended-upgrades"
    #else
    #    UNATTUPG=""
    #fi

    # myNode will manage upgrades since this would make some OS assumptions
    UNATTUPG=""
}

stopServices() {
    # Stop openvpn
    $SUDO echo ":::"
    $SUDO echo -n "::: Stopping OpenVPN service..."
    case ${PLAT} in
        Ubuntu|Debian|*vuan)
            $SUDO service openvpn stop || true
            ;;
        *)
            $SUDO systemctl stop openvpn.service || true
            ;;
    esac
    $SUDO echo " done."
}

getGitFiles() {
    # Setup git repos for base files
    echo ":::"
    echo "::: Checking for existing base files..."
    #if is_repo "${1}"; then
    #    update_repo "${1}" "${2}"
    #else
    #    make_repo "${1}" "${2}"
    #fi
    make_repo "${1}" "${2}"
}

is_repo() {
    # If the directory does not have a .git folder it is not a repo
    echo -n ":::    Checking $1 is a repo..."
    cd "${1}" &> /dev/null || return 1
    $SUDO git status &> /dev/null && echo " OK!"; return 0 || echo " not found!"; return 1
}

make_repo() {
    # Remove the non-repos interface and clone the interface
    echo -n ":::    Cloning $2 into $1..."
    $SUDO rm -rf "${1}"
    sync
    $SUDO git clone -q "${2}" "${1}"
    $SUDO git -C "${1}" checkout ${pivpnVersionHash}
    sync
    if [ -z "${TESTING+x}" ]; then
        :
    else
        $SUDO git -C "${1}" checkout test
    fi
    echo " done!"
}

update_repo() {
    if [[ "${reconfigure}" == true ]]; then
          echo "::: --reconfigure passed to install script. Not downloading/updating local repos"
    else
        # Pull the latest commits
        echo -n ":::     Updating repo in $1..."
        $SUDO rm -rf "${1}"
        $SUDO git clone -q --depth 1 --no-single-branch "${2}" "${1}"

        cd "${1}" || exit 1
        if [ -z "${TESTING+x}" ]; then
            :
        else
            ${SUDOE} git checkout test
        fi
        echo " done!"
    fi
}

setCustomProto() {
    # We'll use UDP
    pivpnProto="udp"
    PROTO="udp"
    $SUDO cp /tmp/pivpnPROTO /etc/pivpn/INSTALL_PROTO
}


setCustomPort() {
    # We'll use port 51194
    PORT=51194
    echo ${PORT} > /tmp/INSTALL_PORT
    $SUDO cp /tmp/INSTALL_PORT /etc/pivpn/INSTALL_PORT
}

setClientDNS() {
    OVPNDNS1="8.8.8.8"
    OVPNDNS2="8.8.4.4"
    $SUDO sed -i '0,/\(dhcp-option DNS \)/ s/\(dhcp-option DNS \).*/\1'${OVPNDNS1}'\"/' /etc/openvpn/server.conf
    $SUDO sed -i '0,/\(dhcp-option DNS \)/! s/\(dhcp-option DNS \).*/\1'${OVPNDNS2}'\"/' /etc/openvpn/server.conf
}

#This procedure allows a user to specify a custom search domain if they have one.
setCustomDomain() {
  DomainSettingsCorrect=False

  #if (whiptail --backtitle "Custom Search Domain" --title "Custom Search Domain" --yesno "Would you like to add a custom search domain? \n (This is only for advanced users who have their own domain)\n" ${r} ${c}); then
  #
  #  until [[ $DomainSettingsCorrect = True ]]
  #  do
  #    if CUSTOMDomain=$(whiptail --inputbox "Enter Custom Domain\nFormat: mydomain.com" ${r} ${c} --title "Custom Domain" 3>&1 1>&2 2>&3); then
  #        if valid_domain "$CUSTOMDomain"; then
  #          if (whiptail --backtitle "Custom Search Domain" --title "Custom Search Domain" --yesno "Are these settings correct?\n    Custom Search Domain: $CUSTOMDomain" ${r} ${c}); then
  #              DomainSettingsCorrect=True
  #
  #              $SUDO sed -i '0,/\(.*dhcp-option.*\)/s//\push "dhcp-option DOMAIN '${CUSTOMDomain}'" \n&/' /etc/openvpn/server.conf
  #
  #          else
  #              # If the settings are wrong, the loop continues
  #              DomainSettingsCorrect=False
  #          fi
  #        else
  #          whiptail --msgbox --backtitle "Invalid Domain" --title "Invalid Domain" "Domain is invalid. Please try again.\n\n    DOMAIN:   $CUSTOMDomain\n" ${r} ${c}
  #          DomainSettingsCorrect=False
  #        fi
  #    else
  #      echo "::: Cancel selected. Exiting..."
  #      exit 1
  #    fi
  #  done
  #
  #else
  #  echo sleep 0.1
  #fi
  sleep 1
}

confOpenVPN() {
    # Generate a random, alphanumeric identifier of 16 characters for this server so that we can use verify-x509-name later that is unique for this server installation. Source: Earthgecko (https://gist.github.com/earthgecko/3089509)
    #(trap - PIPE; cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 16 | head -n 1 > /tmp/pivpn_uuid)
    dd bs=16 count=1 if=/dev/urandom | base64 | tr -dc 'a-zA-Z0-9' > /tmp/pivpn_uuid
    NEW_UUID=$(cat /tmp/pivpn_uuid)
    SERVER_NAME="server_${NEW_UUID}"

    if [[ ${useUpdateVars} == false ]]; then
        # Ask user for desired level of encryption

        if [[ ${useUpdateVars} == false ]]; then
            if [[ ${PLAT} == "Raspbian" ]] && [[ ${OSCN} != "stretch" ]]; then
                APPLY_TWO_POINT_FOUR=false
            else
                #if (whiptail --backtitle "Setup OpenVPN" --title "Installation mode" --yesno "OpenVPN 2.4 brings support for stronger authentication and key exchange using Elliptic Curves, along with encrypted control channel.\n\nIf your clients do run OpenVPN 2.4 or later you can enable these features, otherwise choose 'No' for best compatibility.\n\nNOTE: Current mobile app, that is OpenVPN connect, is supported." ${r} ${c}); then
                #    APPLY_TWO_POINT_FOUR=true
                #    $SUDO touch /etc/pivpn/TWO_POINT_FOUR
                #else
                #    APPLY_TWO_POINT_FOUR=false
                #fi
                APPLY_TWO_POINT_FOUR=false
            fi
        fi

        if [[ ${runUnattended} == true ]] && [[ ${APPLY_TWO_POINT_FOUR} == true ]]; then
            $SUDO touch /etc/pivpn/TWO_POINT_FOUR
        fi

        #if [[ ${APPLY_TWO_POINT_FOUR} == false ]]; then
        #
        #    ENCRYPT=$(whiptail --backtitle "Setup OpenVPN" --title "RSA certificate size" --radiolist \
        #    "Choose the desired size of your certificate (press space to select):\n   This is a certificate that will be generated on your system.  The larger the certificate, the more time this will take.  For most applications, it is recommended to use 2048 bits.  If you are testing, you can use 1024 bits to speed things up, but do not use this for normal use!  If you are paranoid about ... things... then grab a cup of joe and pick 4096 bits." ${r} ${c} 3 \
        #    "1024" "Use a 1024-bit certificate (testing only)" OFF \
        #    "2048" "Use a 2048-bit certificate (recommended level)" ON \
        #    "4096" "Use a 4096-bit certificate (paranoid level)" OFF 3>&1 1>&2 2>&3)
        #else
        #    declare -A ECDSA_MAP=(["256"]="prime256v1" ["384"]="secp384r1" ["521"]="secp521r1")
        #    ENCRYPT=$(whiptail --backtitle "Setup OpenVPN" --title "ECDSA certificate size" --radiolist \
        #    "Choose the desired size of your certificate (press space to select):\n   This is an certificate that will be generated on your system.  The larger the certificate, the more time this will take.  For most applications, it is recommended to use 256 bits.  You can increase the number of bits if you care about, however, consider that 256 bits are already as secure as 3072 bit RSA." ${r} ${c} 3 \
        #    "256" "Use a 256-bit certificate (recommended level)" ON \
        #    "384" "Use a 384-bit certificate" OFF \
        #    "521" "Use a 521-bit certificate (paranoid level)" OFF 3>&1 1>&2 2>&3)
        #fi
        ENCRYPT="2048"

        #exitstatus=$?
        #if [ $exitstatus != 0 ]; then
        #    echo "::: Cancel selected. Exiting..."
        #    exit 1
        #fi
    fi

    # If easy-rsa exists, remove it
    if [[ -d /etc/openvpn/easy-rsa/ ]]; then
        $SUDO rm -rf /etc/openvpn/easy-rsa/
    fi


    # Get easy-rsa
    wget -q -O - "${easyrsaRel}" | $SUDO tar xz -C /etc/openvpn && $SUDO mv /etc/openvpn/EasyRSA-v${easyrsaVer} /etc/openvpn/easy-rsa
    # fix ownership
    $SUDO chown -R root:root /etc/openvpn/easy-rsa
    $SUDO mkdir /etc/openvpn/easy-rsa/pki

    cd /etc/openvpn/easy-rsa || exit

    # Write out new vars file
    set +e
    IFS= read -d '' String <<"EOF"
if [ -z "$EASYRSA_CALLER" ]; then
    echo "Nope." >&2
    return 1
fi
set_var EASYRSA            "/etc/openvpn/easy-rsa"
set_var EASYRSA_PKI        "$EASYRSA/pki"
set_var EASYRSA_CRL_DAYS   3650
EOF
    echo "${String}" | $SUDO tee vars >/dev/null
    set -e

    # Set certificate type
    if [[ ${APPLY_TWO_POINT_FOUR} == false ]]; then
        echo "set_var EASYRSA_ALGO       rsa" | $SUDO tee -a vars
        echo "set_var EASYRSA_KEY_SIZE   ${ENCRYPT}" | $SUDO tee -a vars
    else
        echo "set_var EASYRSA_ALGO       ec" | $SUDO tee -a vars
        echo "set_var EASYRSA_CURVE      ${ECDSA_MAP["${ENCRYPT}"]}" | $SUDO tee -a vars
    fi

    # Remove any previous keys
    ${SUDOE} ./easyrsa --batch init-pki

    # Build the certificate authority
    printf "::: Building CA...\n"
    ${SUDOE} ./easyrsa --batch build-ca nopass
    printf "\n::: CA Complete.\n"

    #if [[ ${useUpdateVars} == false ]]; then
    #    if [[ ${APPLY_TWO_POINT_FOUR} == false ]]; then
    #        whiptail --msgbox --backtitle "Setup OpenVPN" --title "Server Information" "The server key, Diffie-Hellman parameters, and HMAC key will now be generated." ${r} ${c}
    #    fi
    #fi

    # Build the server
    ${SUDOE} ./easyrsa build-server-full ${SERVER_NAME} nopass

    if [[ ${useUpdateVars} == false ]]; then
      if [[ ${APPLY_TWO_POINT_FOUR} == false ]]; then
        if ([ "$ENCRYPT" -ge "4096" ] && whiptail --backtitle "Setup OpenVPN" --title "Download Diffie-Hellman Parameters" --yesno --defaultno "Download Diffie-Hellman parameters from a public DH parameter generation service?\n\nGenerating DH parameters for a $ENCRYPT-bit key can take many hours on a Raspberry Pi. You can instead download DH parameters from \"2 Ton Digital\" that are generated at regular intervals as part of a public service. Downloaded DH parameters will be randomly selected from their database.\nMore information about this service can be found here: https://2ton.com.au/safeprimes/\n\nIf you're paranoid, choose 'No' and Diffie-Hellman parameters will be generated on your device." ${r} ${c}); then
          DOWNLOAD_DH_PARAM=true
        else
          DOWNLOAD_DH_PARAM=false
        fi
      else
        DOWNLOAD_DH_PARAM=false
      fi
    fi

    if [[ ${APPLY_TWO_POINT_FOUR} == false ]]; then
      if [ "$ENCRYPT" -ge "4096" ] && [[ ${DOWNLOAD_DH_PARAM} == true ]]; then
        # Downloading parameters
        ${SUDOE} curl "https://2ton.com.au/getprimes/random/dhparam/${ENCRYPT}" -o "/etc/openvpn/easy-rsa/pki/dh${ENCRYPT}.pem"
      else
        # Generate Diffie-Hellman key exchange
        ${SUDOE} ./easyrsa gen-dh
        ${SUDOE} mv pki/dh.pem pki/dh${ENCRYPT}.pem
      fi
    fi

    # Generate static HMAC key to defend against DDoS
    ${SUDOE} openvpn --genkey --secret pki/ta.key

    # Generate an empty Certificate Revocation List
    ${SUDOE} ./easyrsa gen-crl
    ${SUDOE} cp pki/crl.pem /etc/openvpn/crl.pem
    ${SUDOE} chown nobody:nogroup /etc/openvpn/crl.pem

    # Write config file for server using the template.txt file
    $SUDO cp /etc/.pivpn/server_config.txt /etc/openvpn/server.conf

    if [[ ${APPLY_TWO_POINT_FOUR} == true ]]; then
      #If they enabled 2.4 use tls-crypt instead of tls-auth to encrypt control channel
      $SUDO sed -i "s/tls-auth \/etc\/openvpn\/easy-rsa\/pki\/ta.key 0/tls-crypt \/etc\/openvpn\/easy-rsa\/pki\/ta.key/" /etc/openvpn/server.conf
    fi

    if [[ ${APPLY_TWO_POINT_FOUR} == true ]]; then
      #If they enabled 2.4 disable dh parameters since the key exchange will use the matching curve from the ECDSA certificate
      $SUDO sed -i "s/\(dh \/etc\/openvpn\/easy-rsa\/pki\/dh\).*/dh none/" /etc/openvpn/server.conf
    else
      # Otherwise set the user encryption key size
      $SUDO sed -i "s/\(dh \/etc\/openvpn\/easy-rsa\/pki\/dh\).*/\1${ENCRYPT}.pem/" /etc/openvpn/server.conf
    fi

    # if they modified port put value in server.conf
    if [ $PORT != 1194 ]; then
        $SUDO sed -i "s/1194/${PORT}/g" /etc/openvpn/server.conf
    fi

    # if they modified protocol put value in server.conf
    if [ "$PROTO" != "udp" ]; then
        $SUDO sed -i "s/proto udp/proto tcp/g" /etc/openvpn/server.conf
    fi

    # write out server certs to conf file
    $SUDO sed -i "s/\(key \/etc\/openvpn\/easy-rsa\/pki\/private\/\).*/\1${SERVER_NAME}.key/" /etc/openvpn/server.conf
    $SUDO sed -i "s/\(cert \/etc\/openvpn\/easy-rsa\/pki\/issued\/\).*/\1${SERVER_NAME}.crt/" /etc/openvpn/server.conf
}

confUnattendedUpgrades() {
    # myNode Removed
    echo "skipped confUnattendedUpgrades"
}

confNetwork() {
    # Enable forwarding of internet traffic
    $SUDO sed -i '/net.ipv4.ip_forward=1/s/^#//g' /etc/sysctl.conf
    $SUDO sysctl -p

    # if ufw enabled, configure that (running as root because sometimes the executable is not in the user's $PATH, on Debian for example)
    if $SUDO bash -c 'hash ufw' 2>/dev/null; then
        if LANG=en_US.UTF-8 $SUDO ufw status | grep -q inactive
        then
            noUFW=1
        else
            echo "::: Detected UFW is enabled."
            echo "::: Adding UFW rules..."
            $SUDO sed "/delete these required/i *nat\n:POSTROUTING ACCEPT [0:0]\n-I POSTROUTING -s 10.8.0.0/24 -o $IPv4dev -j MASQUERADE\nCOMMIT\n" -i /etc/ufw/before.rules
            # Insert rules at the beginning of the chain (in case there are other rules that may drop the traffic)
            $SUDO ufw insert 1 allow "$PORT"/"$PROTO" >/dev/null
            # Don't forward everything, just the traffic originated from the VPN subnet
            $SUDO ufw route insert 1 allow in on tun0 from 10.8.0.0/24 out on "$IPv4dev" to any >/dev/null
            $SUDO ufw reload >/dev/null
            echo "::: UFW configuration completed."
        fi
    else
        noUFW=1
    fi
    # else configure iptables
    if [[ $noUFW -eq 1 ]]; then
        echo 1 > /tmp/noUFW
        $SUDO iptables -t nat -I POSTROUTING -s 10.8.0.0/24 -o "$IPv4dev" -j MASQUERADE
        case ${PLAT} in
            Ubuntu|Debian|Devuan)
                $SUDO iptables-save | $SUDO tee /etc/iptables/rules.v4 > /dev/null
                ;;
            *)
                $SUDO netfilter-persistent save
                ;;
        esac
    else
        echo 0 > /tmp/noUFW
    fi

    $SUDO cp /tmp/noUFW /etc/pivpn/NO_UFW
}

confOVPN() {
    if ! IPv4pub=$(dig +short myip.opendns.com @208.67.222.222) || ! valid_ip "$IPv4pub"; then
        echo "dig failed, now trying to curl checkip.amazonaws.com"
        if ! IPv4pub=$(curl -s https://checkip.amazonaws.com) || ! valid_ip "$IPv4pub"; then
            echo "checkip.amazonaws.com failed, please check your internet connection/DNS"
            exit 1
        fi
    fi
    $SUDO cp /tmp/pivpnUSR /etc/pivpn/INSTALL_USER
    $SUDO cp /tmp/DET_PLATFORM /etc/pivpn/DET_PLATFORM

    $SUDO cp /etc/.pivpn/Default.txt /etc/openvpn/easy-rsa/pki/Default.txt

    if [[ ${APPLY_TWO_POINT_FOUR} == true ]]; then
      #If they enabled 2.4 remove key-direction options since it's not required
      $SUDO sed -i "/key-direction 1/d" /etc/openvpn/easy-rsa/pki/Default.txt
    fi

    if [[ ${useUpdateVars} == false ]]; then
        #METH=$(whiptail --title "Public IP or DNS" --radiolist "Will clients use a Public IP or DNS Name to connect to your server (press space to select)?" ${r} ${c} 2 \
        #"$IPv4pub" "Use this public IP" "ON" \
        #"DNS Entry" "Use a public DNS" "OFF" 3>&1 1>&2 2>&3)
        METH=$IPv4pub

        exitstatus=$?
        if [ $exitstatus != 0 ]; then
            echo "::: Cancel selected. Exiting..."
            exit 1
        fi

        if [ "$METH" == "$IPv4pub" ]; then
            $SUDO sed -i 's/IPv4pub/'"$IPv4pub"'/' /etc/openvpn/easy-rsa/pki/Default.txt
        else
            until [[ $publicDNSCorrect = True ]]
            do
                PUBLICDNS=$(whiptail --title "PiVPN Setup" --inputbox "What is the public DNS name of this Server?" ${r} ${c} 3>&1 1>&2 2>&3)
                exitstatus=$?
                if [ $exitstatus != 0 ]; then
                echo "::: Cancel selected. Exiting..."
                exit 1
                fi
                if (whiptail --backtitle "Confirm DNS Name" --title "Confirm DNS Name" --yesno "Is this correct?\n\n Public DNS Name:  $PUBLICDNS" ${r} ${c}) then
                    publicDNSCorrect=True
                    $SUDO sed -i 's/IPv4pub/'"$PUBLICDNS"'/' /etc/openvpn/easy-rsa/pki/Default.txt
                else
                    publicDNSCorrect=False
                fi
            done
        fi
    else
        $SUDO sed -i 's/IPv4pub/'"$PUBLICDNS"'/' /etc/openvpn/easy-rsa/pki/Default.txt
    fi

    # if they modified port put value in Default.txt for clients to use
    if [ $PORT != 1194 ]; then
        $SUDO sed -i -e "s/1194/${PORT}/g" /etc/openvpn/easy-rsa/pki/Default.txt
    fi

    # if they modified protocol put value in Default.txt for clients to use
    if [ "$PROTO" != "udp" ]; then
        $SUDO sed -i -e "s/proto udp/proto tcp/g" /etc/openvpn/easy-rsa/pki/Default.txt
    fi

    # verify server name to strengthen security
    $SUDO sed -i "s/SRVRNAME/${SERVER_NAME}/" /etc/openvpn/easy-rsa/pki/Default.txt

    if [ ! -d "/home/$pivpnUser/ovpns" ]; then
        $SUDO mkdir "/home/$pivpnUser/ovpns"
    fi
    $SUDO chmod 0777 -R "/home/$pivpnUser/ovpns"
}

confLogging() {
  echo "if \$programname == 'ovpn-server' then /var/log/openvpn.log
if \$programname == 'ovpn-server' then stop" | $SUDO tee /etc/rsyslog.d/30-openvpn.conf > /dev/null

  echo "/var/log/openvpn.log
{
    rotate 4
    weekly
    missingok
    notifempty
    compress
    delaycompress
    sharedscripts
    postrotate
        invoke-rc.d rsyslog rotate >/dev/null 2>&1 || true
    endscript
}" | $SUDO tee /etc/logrotate.d/openvpn > /dev/null

  # Restart the logging service
  case ${PLAT} in
    Ubuntu|Debian|*vuan)
      $SUDO service rsyslog restart || true
      ;;
    *)
      $SUDO systemctl restart rsyslog.service || true
      ;;
  esac
}

finalExports() {
    # Update variables in setupVars.conf file
    if [ -e "${setupVars}" ]; then
        $SUDO sed -i.update.bak '/pivpnUser/d;/UNATTUPG/d;/pivpnInterface/d;/IPv4dns/d;/IPv4addr/d;/IPv4gw/d;/pivpnProto/d;/PORT/d;/ENCRYPT/d;/DOWNLOAD_DH_PARAM/d;/PUBLICDNS/d;/OVPNDNS1/d;/OVPNDNS2/d;' "${setupVars}"
    fi
    {
        echo "pivpnUser=${pivpnUser}"
        echo "UNATTUPG=${UNATTUPG}"
        echo "pivpnInterface=${pivpnInterface}"
        echo "IPv4dns=${IPv4dns}"
        echo "IPv4addr=${IPv4addr}"
        echo "IPv4gw=${IPv4gw}"
        echo "pivpnProto=${pivpnProto}"
        echo "PORT=${PORT}"
        echo "ENCRYPT=${ENCRYPT}"
        echo "APPLY_TWO_POINT_FOUR=${APPLY_TWO_POINT_FOUR}"
        echo "DOWNLOAD_DH_PARAM=${DOWNLOAD_DH_PARAM}"
        echo "PUBLICDNS=${PUBLICDNS}"
        echo "OVPNDNS1=${OVPNDNS1}"
        echo "OVPNDNS2=${OVPNDNS2}"
    } | $SUDO tee "${setupVars}" > /dev/null
}


# I suggest replacing some of these names.

#accountForRefactor() {
#    # At some point in the future this list can be pruned, for now we'll need it to ensure updates don't break.
#
#    # Refactoring of install script has changed the name of a couple of variables. Sort them out here.
#    sed -i 's/pivpnUser/PIVPN_USER/g' ${setupVars}
#    #sed -i 's/UNATTUPG/UNATTUPG/g' ${setupVars}
#    sed -i 's/pivpnInterface/PIVPN_INTERFACE/g' ${setupVars}
#    sed -i 's/IPv4dns/IPV4_DNS/g' ${setupVars}
#    sed -i 's/IPv4addr/IPV4_ADDRESS/g' ${setupVars}
#    sed -i 's/IPv4gw/IPV4_GATEWAY/g' ${setupVars}
#    sed -i 's/pivpnProto/TRANSPORT_LAYER/g' ${setupVars}
#    #sed -i 's/PORT/PORT/g' ${setupVars}
#    #sed -i 's/ENCRYPT/ENCRYPT/g' ${setupVars}
#    #sed -i 's/DOWNLOAD_DH_PARAM/DOWNLOAD_DH_PARAM/g' ${setupVars}
#    sed -i 's/PUBLICDNS/PUBLIC_DNS/g' ${setupVars}
#    sed -i 's/OVPNDNS1/OVPN_DNS_1/g' ${setupVars}
#    sed -i 's/OVPNDNS2/OVPN_DNS_2/g' ${setupVars}
#}

installPiVPN() {
    stopServices
    $SUDO mkdir -p /etc/pivpn/
    confUnattendedUpgrades
    installScripts
    setCustomProto
    setCustomPort
    confOpenVPN
    confNetwork
    confOVPN
    setClientDNS
    setCustomDomain
    confLogging
    finalExports
}

updatePiVPN() {
    #accountForRefactor
    stopServices
    confUnattendedUpgrades
    installScripts

    # setCustomProto
    # write out the PROTO
    PROTO=$pivpnProto
    $SUDO cp /tmp/pivpnPROTO /etc/pivpn/INSTALL_PROTO

    #setCustomPort
    # write out the port
    $SUDO cp /tmp/INSTALL_PORT /etc/pivpn/INSTALL_PORT

    confOpenVPN
    confNetwork
    confOVPN

    # ?? Is this always OK? Also if you only select one DNS server ??
    $SUDO sed -i '0,/\(dhcp-option DNS \)/ s/\(dhcp-option DNS \).*/\1'${OVPNDNS1}'\"/' /etc/openvpn/server.conf
    $SUDO sed -i '0,/\(dhcp-option DNS \)/! s/\(dhcp-option DNS \).*/\1'${OVPNDNS2}'\"/' /etc/openvpn/server.conf

    finalExports #re-export setupVars.conf to account for any new vars added in new versions
}


displayFinalMessage() {
    # Final completion message to user
    #whiptail --msgbox --backtitle "Make it so." --title "Installation Complete!" "Now run 'pivpn add' to create the ovpn profiles.
#Run 'pivpn help' to see what else you can do!\n\nIf you run into any issue, please read all our documentation carefully.
#All incomplete posts or bug reports will be ignored or deleted.\n\nThank you for using PiVPN." ${r} ${c}
    
    #if (whiptail --title "Reboot" --yesno --defaultno "It is strongly recommended you reboot after installation.  Would you like to reboot now?" ${r} ${c}); then
    #    whiptail --title "Rebooting" --msgbox "The system will now reboot." ${r} ${c}
    #    printf "\nRebooting system...\n"
    #    $SUDO sleep 3
    #    $SUDO shutdown -r now
    #fi

    echo "Installation Complete!"
}

update_dialogs() {
    # Always "update"
    useUpdateVars=false
}

clone_or_update_repos() {
    if [[ "${reconfigure}" == true ]]; then
        echo "::: --reconfigure passed to install script. Not downloading/updating local repos"
    else
        # Get Git files
        getGitFiles ${pivpnFilesDir} ${pivpnGitUrl} || \
        { echo "!!! Unable to clone ${pivpnGitUrl} into ${pivpnFilesDir}, unable to continue."; \
            exit 1; \
        }
    fi
}


######## SCRIPT ############

main() {

    ######## FIRST CHECK ########
    # Must be root to install
    echo ":::"
    if [[ $EUID -eq 0 ]];then
        echo "::: You are root."
    else
        echo "::: sudo will be used for the install."
        # Check if it is actually installed
        # If it isn't, exit because the install cannot complete
        if [[ $(dpkg-query -s sudo) ]];then
            export SUDO="sudo"
            export SUDOE="sudo -E"
        else
            echo "::: Please install sudo or run this as root."
            exit 1
        fi
    fi

    # Check for supported distribution
    distro_check

    # Check arguments for the undocumented flags
    for var in "$@"; do
        case "$var" in
            "--reconfigure"  ) reconfigure=true;;
            "--i_do_not_follow_recommendations"   ) skipSpaceCheck=false;;
            "--unattended"     ) runUnattended=true;;
        esac
    done

    if [[ -f ${setupVars} ]]; then
        if [[ "${runUnattended}" == true ]]; then
            echo "::: --unattended passed to install script, no whiptail dialogs will be displayed"
            useUpdateVars=true
        else
            update_dialogs
        fi
    fi

    # Start the installer
    # Verify there is enough disk space for the install
    if [[ "${skipSpaceCheck}" == true ]]; then
        echo "::: --i_do_not_follow_recommendations passed to script, skipping free disk space verification!"
    else
        verifyFreeDiskSpace
    fi

    # Install the packages (we do this first because we need whiptail)
    addSoftwareRepo

    update_package_cache

    # Notify user of package availability
    notify_package_updates_available

    # Install packages used by this installation script
    install_dependent_packages PIVPN_DEPS[@]

    if [[ ${useUpdateVars} == false ]]; then
        # Display welcome dialogs
        welcomeDialogs

        # Find interfaces and let the user choose one
        chooseInterface

        # Only try to set static on Raspbian, otherwise let user do it
        if [[ $PLAT != "Raspbian" ]]; then
            avoidStaticIPv4Ubuntu
        else
            setStaticIPv4
        fi

        # Choose the user for the ovpns
        chooseUser

        # Ask if unattended-upgrades will be enabled
        unattendedUpgrades

        # Clone/Update the repos
        clone_or_update_repos

        # Install
        if installPiVPN; then
            echo "::: Install Complete..."
        else
            exit 1
        fi
    else
        # Source ${setupVars} for use in the rest of the functions.
        source ${setupVars}

        echo "::: Using IP address: $IPv4addr"
        echo "${IPv4addr%/*}" > /tmp/pivpnIP
        echo "::: Using interface: $pivpnInterface"
        echo "${pivpnInterface}" > /tmp/pivpnINT
        echo "::: Using User: $pivpnUser"
        echo "${pivpnUser}" > /tmp/pivpnUSR
        echo "::: Using protocol: $pivpnProto"
        echo "${pivpnProto}" > /tmp/pivpnPROTO
        echo "::: Using port: $PORT"
        echo ${PORT} > /tmp/INSTALL_PORT
        echo ":::"

        # Only try to set static on Raspbian
        case ${PLAT} in
          Rasp*)
            setStaticIPv4 # This might be a problem if a user tries to modify the ip in the config file and then runs an update because of the way we check for previous configuration in /etc/dhcpcd.conf
            ;;
          *)
            echo "::: IP Information"
            echo "::: Since we think you are not using Raspbian, we will not configure a static IP for you."
            echo "::: If you are in Amazon then you can not configure a static IP anyway."
            echo "::: Just ensure before this installer started you had set an elastic IP on your instance."
            ;;
          esac

        # Clone/Update the repos
        clone_or_update_repos


        updatePiVPN
    fi

    echo "::: Restarting services..."
    # Start services
    case ${PLAT} in
        Ubuntu|Debian|*vuan)
            $SUDO service openvpn start
            ;;
        *)
            $SUDO systemctl enable openvpn.service
            $SUDO systemctl start openvpn.service
            ;;
    esac
    
    # Ensure that cached writes reach persistent storage
    echo "::: Flushing writes to disk..."
    sync

    echo "::: done."

    if [[ "${useUpdateVars}" == false ]]; then
        displayFinalMessage
    fi

    echo ":::"
    if [[ "${useUpdateVars}" == false ]]; then
        echo "::: Installation Complete!"
        echo "::: Now run 'pivpn add' to create an ovpn profile for each of your devices."
        echo "::: Run 'pivpn help' to see what else you can do!"
        echo "::: It is strongly recommended you reboot after installation."
    else
        echo "::: Update complete!"
    fi

    echo ":::"
}

if [[ "${PIVPN_TEST}" != true ]] ; then
  main "$@"
fi