VPN Routing, DD-WRT Startup Script

ddwrt-vpn

#!/bin/sh
#
# https://ipinfo.io/ASXXXXX
# https://ipinfo.io/countries/us
# curl https://api.hackertarget.com/aslookup/?q=example

set -e

default_iface=$(route | grep default | sed -n "s/^default .* \(.*\)$/\1/p")
vpn_iface=ppp0

asn_add() {
  iface=$1
  asn=$2
  addresses=$(wget -qO- http://ipinfo.io/AS${asn} 2>/dev/null | grep -E "a href.*${asn}\/" | grep -v ":" | sed "s/^.*<a href=\"\/AS${asn}\///; s/\" >//")
  for address in $addresses; do
      ip route flush $address
      ip route add $address dev $iface
  done
  return 0
}

asn_lookup() {
  iface=$1
  name=$2
  results=$(wget -qO- http://api.hackertarget.com/aslookup/?q=$name | grep -E ', US"$' | cut -d, -f1 | sed -e 's/^"//' -e 's/"$//')
  for asn in $results; do
      asn_add $iface $asn
  done
  return 0
}

flash_red() {
  io=0
  seconds=0
  while true; do
    if [ "$(date +%s)" -gt "$((seconds+1))" ]; then
      if [ "$io" -eq "0" ]; then
        io=1 && (gpio disable 15 && gpio enable 16)
      else
        io=0 && (gpio enable 15 && gpio enable 16)
      fi
    	seconds=$(date +%s)
    fi
  done
  return 0
}

flash_white() {
  io=0
  seconds=0
  while true; do
    if [ "$(date +%s)" -gt "$((seconds+1))" ]; then
      if [ "$io" -eq "0" ]; then
        io=1 && (gpio enable 15 && gpio enable 16)
      else
        io=0 && (gpio disable 15 && gpio disable 16)
      fi
    	seconds=$(date +%s)
    fi
  done
  return 0
}

flash_red &
flash_red_pid=$!

# wait for $vpn_iface to connect
while [ -z "$(ifconfig $vpn_iface | grep "inet addr" | sed -n "s/^.* inet addr:\([^ ]*\) .*$/\1/p")" ]; do
  sleep 10
done

sleep 10

kill -9 $flash_red_pid

flash_white &
flash_white_pid=$!

# using default=vpn will cause the default gateway to be $vpn_iface,
# and other asn listed will instead use $default_iface
options="default=off google amazon incapsula akamai netflix"
#options=$(wget -qO- http://s3.amazonaws.com/path/to/file)

asn_iface=$vpn_iface

if [ "$(echo $options | tr ' ' '\n' | grep 'default=vpn')" == "default=vpn" ]; then
  route del default $default_iface
  route add default dev $vpn_iface
  asn_iface=$default_iface
fi

for option in $options; do
  [ "$option" == "default=vpn" ] && continue
  asn_lookup $asn_iface $option
done

sleep 10

kill -9 $flash_white_pid

gpio enable 15 && gpio enable 16