001-dnsswitcher.1d.sh

#!/usr/bin/env bash
#
# DNS Switcher
# The list of DNS options should be defined on this file
#
# rewrite of https://github.com/matryer/bitbar-plugins/blob/master/Network/dnsswitcher.1d.sh
# by M Saiqul Haq (@saiqulhaq)
#
# <xbar.title>DNS Switcher</xbar.title>
# <xbar.version>v2.1.7-beta</xbar.version>
# <xbar.author>Lucas Romero</xbar.author>
# <xbar.author.github>luqasn</xbar.author.github>
# <xbar.desc>Switch DNS to your defined DNS options.</xbar.desc>

# Configuration

# add or remove list of DNS options below, don't forget to make it enabled. see below
# shellcheck disable=2034
cloudflare="1.1.1.1 1.0.0.1"

# shellcheck disable=2034
google="8.8.8.8 8.8.4.4 2001:4860:4860::8888 2001:4860:4860::8844"

# shellcheck disable=2034
level3="209.244.0.3 209.244.0.4 4.2.2.1 4.2.2.2 4.2.2.3 4.2.2.4"

# shellcheck disable=2034
opendns="208.67.222.222 208.67.220.220"

# shellcheck disable=2034
norton="199.85.126.10 199.85.127.10 199.85.126.20 199.85.127.20 199.85.126.30 199.85.127.30"

localhost="127.0.0.1"

# shellcheck disable=2034
default="empty"

enabled_dns_address=(default localhost)
########################


get_interface() {
  while read -r line; do
      sname="$(echo "$line" | sed -E 's|(.*) \(Hardware Port: (.+), Device: (.+)\)|\1|')"
      sdev="$(echo "$line" | sed -E 's|(.*) \(Hardware Port: (.+), Device: (.+)\)|\3|')"
      if [ -n "$sdev" ]; then
          ifout="$(ifconfig "$sdev" 2>/dev/null)"
          echo "$ifout" | grep 'status: active' > /dev/null 2>&1
          rc="$?"
          if [ "$rc" -eq 0 ]; then
              echo "$sname"
              break
          fi
      fi
  done <<< "$(networksetup -listnetworkserviceorder | awk 'BEGIN { RS = "\\([0-9]\+\\) " ; FS = "\n" } { print $1, $2 }')"

  if [ -z "$currentservice" ]; then
      >&2 echo "Could not find current service"
      exit 1
  fi
}

flushcache(){
	killall -HUP mDNSResponder &>/dev/null
	sudo killall mDNSResponderHelper &>/dev/null
	sudo dscacheutil -flushcache &>/dev/null
}

selected_dns="Unknown"
network_service="$(get_interface)"
current_dns_output=$(networksetup -getdnsservers "$network_service")

if [[ $current_dns_output == There* ]] # For e.g. "There aren't any DNS Servers set on Wi-Fi."
then
    selected_dns="default"
else
    IFS=', ' read -r -a current_dns_address <<< "$current_dns_output"

    for dns_name in "${enabled_dns_address[@]}"
    do
        for current_dns in "${current_dns_address[@]}"
        do
        dns_option="${!dns_name}"
            if [[ $dns_option == *"$current_dns"* ]]
            then
                selected_dns="$dns_name"
            fi
        done
    done
fi

get_interfaces
return


### Bitbar Menu
if [[ $selected_dns == "Unknown" ]]
then
    echo "Unrecognized DNS"
else
    echo "$selected_dns"
fi

echo "---"

for dns_name in "${enabled_dns_address[@]}"
do
  echo "$dns_name | shell=$0 | param1='${dns_name}' | terminal=false | refresh=true"
done

case "$0" in
  *\ * )
   echo "Your script path | color=#ff0000"
   echo "($0) | color=#ff0000"
   echo "has a space in it, which BitBar does not support. | color=#ff0000"
  ;;
esac

if [ ! -z "$1" ]; then
  networksetup -setdnsservers "$network_service" ${!1}
  /usr/bin/osascript -e "do shell script \"flushcache\" with prompt \"DNS caches should be flushed after switching servers.\" with administrator privileges"
fi