Start and stop strongswan vpn's in linux in a sane manner

linux_vpn.sh

#! /bin/bash

# Manage our vpn connections from the commandline in an IAC way. This script 
# should just be alias'd in your shell rc file for ease of use.

# TODO:
#
# validate consul datacenters
# ensure only one vpn connection is up
# provide vpn details if requested
# in verbose down, output the resolv.conf
# need to look for the dns entry via regex to ensure I grab the right one
# create alias in rc file

readonly NC='\033[0m'
readonly RED='\033[0;31m'
readonly BLUE='\033[0;34m'
readonly GREEN='\033[0;32m'
readonly ARGS="$@"

verbose() {
  echo -e "$BLUE Action:      $NC $ACTION"
  echo -e "$BLUE VPN Network: $NC $NETWORK"
  echo -e "$BLUE VPN Environment: $NC $ENVIRONMENT"
  echo $ip_info
  echo $dns_info
  echo $cleanup_info
}

# confirm that the consul dns is resolving correctly
confirm_dns() {
#  local dc="us-east-1-z"
  sleep 5
  dns_info="$(fping core-consul-0.node.$NETWORK.consul)"
  if [ ! $? ]; then
     echo -e "$RED \nDNS resolution failed $NC"
     echo -e "$RED $out $NC"
     exit 1
  fi
}

# This will fix the annoying dns issue of the servers being in the wrong order. 
# At some point I will go back and fix this within strongswan.
fix_dns() { 
  sed -n '3p' /etc/resolv.conf > /tmp/dns.conf
  cat /etc/resolv.conf >> /tmp/dns.conf
  sed -i".bak" '4d' /tmp/dns.conf
  cp /tmp/dns.conf /etc/resolv.conf
  confirm_dns
}

# remove tmp files created
cleanup() {
  cleanup_info="$(rm /tmp/dns*)"
}

# need to make sure only one vpn connection is running and if not then ask are you sure.
check_vpn() {
 echo "need to implement"
 return true
}

# usage details
usage() {
  echo "do shit"
}

main() {

  # parse the arguements
  for i in $ARGS
do
case $i in
    -n=*|--network=*)
    readonly NETWORK="${i#*=}"
    shift
    ;;
    -v=*|--verbose=*)
    readonly VERBOSE="${i#*=}"
    shift
    ;;
    -e=*|--environment=*)
    readonly ENVIRONMENT="${i#*=}"
    shift
    ;;
    -a=*|--action=*)
    readonly ACTION="${i#*=}"
    shift
    ;;
    -h=*|--help=*)
    readonly HELP="${i#*=}"
    shift
    ;;
    *)
    ;;
esac
done

  if [ $HELP ]; then
    usage
    exit 0
  fi

  if [ check_vpn ]; then
    if [ $ACTION == "up" ]; then
      echo "starting vpn"
      ip_info="$(ipsec $ACTION $NETWORK-$ENVIRONMENT)"
      fix_dns
    elif [ $ACTION == "down" ]; then
      echo "stoppping vpn"
      ip_info="$(ipsec $ACTION $NETWORK-$ENVIRONMENT)"
      cleanup_info="$(cleanup)"
    fi
  fi

  if [ $VERBOSE ]; then
    verbose
  fi
}

# do work
main