sh vpn.sh

Posted 2021-05-07

#!/bin/bash

PROG_NAME=$0
ACTION=$1

usage() {
  echo "Usage: $PROG_NAME {list|ping|optimal|conn|close|status}"
  exit 1
}

get_services() {
  local protocol=${1:-"L2TP|PPTP"}
  scutil --nc list | grep -iE "$protocol" | awk -F'"' '{print $2}' 
}

get_service_addr() {
  local service=$1
  scutil --nc show "$service" | awk '$1~/CommRemoteAddress/{print $3}'
}

vpn_list() {
  local protocol=$1
  IFS=$'\n' && declare -a services=( `get_services $protocol` )
  for service in "${services[@]}";do
    addr=$(get_service_addr $service)
    echo "$service: $addr"
  done
}

vpn_test() {
  local protocol=$1
  declare -a hosts=()
  IFS=$'\n' && declare -a services=( `get_services $protocol` )

  for service in "${services[@]}";do
    host=$(scutil --nc show "$service" | awk '$1~/CommRemoteAddress/{print $3}')
    [[ "${hosts[*]}" =~ "$host" ]] || hosts+=("$host")  
  done

  for h in "${hosts[@]}";do
    ping -c3 $h 2>/dev/null | tail -1 | cut -d'=' -f2 | cut -d'/' -f2 | xargs -I {} echo "$h " {} 2>/dev/null &
  done

  children=$(jobs -p | xargs)
  trap 'kill $children >/dev/null 2>&1' SIGINT SIGTERM
  wait
}

get_protocol() {
  local service=$1
  scutil --nc show "$service" | awk -F':|]' 'NR==1{print $(NF-1)}'
}

get_fastest_service() {
  local protocol=$1
  local host=$(vpn_test $protocol 2>/dev/null | sort -nk2 | head -1 | awk '{print $1}')

  if [ -z "$protocol" ];then
    vpn_list | grep "$host" | cut -d':' -f1 | head -1
  else
    vpn_list $protocol | grep "$host" | cut -d':' -f1
  fi
}

to_upper() { 
  echo ${@^^} 
}

vpn_status() {
  which ack >/dev/null 2>&1
  if [ $? -eq 0 ];then
    scutil --nc list | grep -E "L2TP|PPTP" | ack --passthru Connected
  else
    scutil --nc list | grep -E "L2TP|PPTP"
  fi
}

vpn_connect() {
  local service=$1

/usr/bin/env osascript <<-EOF
  tell application "System Events"
    tell current location of network preferences
      set VPN to service "$service" -- your VPN name here
      if exists VPN then connect VPN
      repeat while (current configuration of VPN is not connected)
        delay 1
      end repeat
    end tell
  end tell
EOF
}

get_connected_service() {
  vpn_status | awk '$2~/Connected/' | awk -F'"' '{print $2}'
}

vpn_disconnect() {
  local service=$1

/usr/bin/env osascript <<-EOF
  tell application "System Events"
    tell current location of network preferences
      set VPN to service "$service" -- your VPN name here
      if exists VPN then disconnect VPN
    end tell
  end tell
  return
EOF
}

case "$ACTION" in
    ping|test)
        vpn_test
    ;;
    optimal)
        shift
        get_fastest_service $@
    ;;
    list)
        vpn_list
    ;;
    conn)
        shift && service="$(get_fastest_service $@)"
        vpn_connect "$service"
        [ $? -eq 0 ] && echo "ok, $service connected."
    ;;
    close)
        service=$(get_connected_service) 
        [ -z "$service" ] && echo "not connected to any service." && exit 0
        vpn_disconnect "$service"
        [ $? -eq 0 ] && echo "ok, $service disconnected."
    ;;
    status)
        vpn_status
    ;;
    *)
        usage
    ;;
esac