dns-check.sh

#!/bin/bash
#                                                          +----+----+----+----+
#                                                          |    |    |    |    |
# Author: Mark David Scott Cunningham                      | M  | D  | S  | C  |
#                                                          +----+----+----+----+
# Created: 2013-12-05
# Updated: 2017-10-04
#
#

# Setup color and formatting codes
      BLACK=$(tput setaf 0)
        RED=$(tput setaf 1)
      GREEN=$(tput setaf 2)
     YELLOW=$(tput setaf 3)
       BLUE=$(tput setaf 4)
    MAGENTA=$(tput setaf 5)
       CYAN=$(tput setaf 6)
      WHITE=$(tput setaf 7)
     BRIGHT=$(tput bold)
     NORMAL=$(tput sgr0)
      BLINK=$(tput blink)
    REVERSE=$(tput smso)
  UNDERLINE=$(tput smul)
# example color code usage:
# echo "${RED}this is red ${NORMAL}this is normal"
# printf "%-40s\n" "${BLUE}This text is blue${NORMAL}"

# Set default recordType and display
recordType="A"
highlight=0
linetwo=0
digopts="+time=2 +tries=2 +short"

# Output correct usage for bad inputs
function usage(){
echo "
${BRIGHT}Usage:${NORMAL} $0 [options] domain [domain2 domain3 ...]

${BRIGHT}-a|--anycast${NORMAL} ...... Use the LW anycast caching server list.
${BRIGHT}-l|--links${NORMAL} ........ Generate links to the Global DNS Checker page and exit.
${BRIGHT}-2|--secondline${NORMAL} ... Display the second line of a record lookup response.
${BRIGHT}-n|--new${NORMAL} <Record> . Check if the record lookup matches the new record.
${BRIGHT}-t|--type${NORMAL} <Type> .. Change the requested record type of lookup.
${BRIGHT}-v|--verbose${NORMAL} ...... Switch the dig from '+short' to '+short +noshort'
${BRIGHT}-h|--help${NORMAL} ......... Show this help/usage message.

${BRIGHT}ALLOWED RECORD TYPES:${NORMAL}
    A ..... IPv4 Address
    AAAA .. IPv6 Address
    CNAME . CNAME (Alias)
    MX .... Mail Exchange
    NS .... Name Server
    TXT ... Text Record
    SOA ... Start of Authority
    PTR.... PTR/rDNS Records
"
}

# Source of all the dns servers used
# http://public-dns.tk/

if [[ -f nameserver ]]; then
# Read in data from local file
 data=($(cat nameserver))
else
# Read in data from remote file
 data=($(curl -sL http://sh.mdsc.info/nameserver))
fi

# Execute Getopt
OPTIONS=$(getopt -o "hal2t:n:v" --long "help,anycast,links,secondline,type:,new:,verbose" -- "$@")

# Check for bad arguments
if [ $? -ne 0 ] ; then usage ; exit 1 ; fi

# Magic
eval set -- "$OPTIONS"

# Evaluate the options for their options
while true; do
 case "$1" in
  -h|--help)
    usage; exit 1;;

  -a|--anycast)
    data='';
    if [[ -f anycast ]]; then
      data=($(cat anycast))
    else
      data=($(curl -sL sh.mdsc.info/anycast))
    fi ;;

  -l|--links)
    #echo "$@"
    echo; shift; shift;
      for domain in "$@"; do
        echo "${BLUE}https://www.whatsmydns.net/${CYAN}#$(echo $recordType | sed 's/\(.*\)/\U\1/g')${NORMAL}/$domain"
      done; echo
    exit;;
  -2|--secondline)
    # Set response to be the second line of the record
    linetwo=1;;
  -t|--type)
    # Set recordType to option parameter and check for valid input
    recordType="$2";
    case $recordType in
      A|a) shift;;
      AAAA|aaaa) shift;;
      CNAME|cname) shift;;
      MX|mx) shift;;
      NS|ns) shift;;
      TXT|txt) shift;;
      SOA|soa) shift;;
      PTR|ptr|RDNS|rdns|X|x) recordType="-x"; shift;;
      *)
      echo "$recordType is not an allowed record type"; echo
      usage; exit 1;;
    esac;;
  -n|--new)
    highlight=1
    newResult="$2"; shift;;
  -v|--verbose)
    digopts="+time=2 +tries=2 +short +noshort" ;;
  --)
    # Announce the type of record lookup
    echo "${RED}Checking ${YELLOW}$recordType ${RED}Records for the following domain(s) ${YELLOW}...${NORMAL}"
    shift; break;;
  *)
    usage; exit 1;;
 esac; shift
done

# Find length of primary array
dataLen=${#data[@]}

# Create secondary arrays from primary array
for (( i=0; i<$dataLen; i += 3 )); do
  nameserver=("${nameserver[@]}" ${data[$i]})
  location=("${location[@]}" ${data[($i+1)]})
  ipaddress=("${ipaddress[@]}" ${data[($i+2)]})
done

# Find length of secondary arrays
namLen=${#nameserver[@]}; locLen=${#location[@]}

# Sanity Checking - Make sure arrays are the same length
if [ $namLen = $locLen ]; then echo

# Iterate through the array of domain parameters
for domain in "$@"; do
  echo "${WHITE}========== $domain ==========${NORMAL}"
  echo "https://www.whatsmydns.net/#$(echo $recordType | sed 's/\(.*\)/\U\1/g')/$domain"

  # Iterate through the array of nameservers
  i=0; for (( $i; i<$namLen; i++ )); do
    if [[ $linetwo = 1 ]]; then
      result=$(dig $digopts "$recordType" "$domain" @"${ipaddress[i]}" | head -n2 | tail -n1 | grep -v '^;;')
    else
      result=$(dig $digopts "$recordType" "$domain" @"${ipaddress[i]}" | head -n1 | grep -v '^;;')
    fi
    if [[ $highlight = 1 && $result = $newResult ]]; then
      printf "${BLUE}%-30s ${NORMAL}: ${BLUE}%-26s ${NORMAL}: ${RED}%s\n${NORMAL}" "${nameserver[i]}" "$(echo ${location[i]} | sed s/_/\ /g)" "$result"
    else
      printf "${BLUE}%-30s ${NORMAL}: ${BLUE}%-26s ${NORMAL}: ${CYAN}%s\n${NORMAL}" "${nameserver[i]}" "$(echo ${location[i]} | sed s/_/\ /g)" "$result"
    fi
  done #end nameserver for loop

  echo
#Pause between domains
#read -p "Press [Enter] to continue ..."

done #end domain for loop

else # Error message if sanity check not passed
  echo "${RED}Nameserver Count = $namLen"; echo "Location Count = $locLen"
  echo "Array Lengths Do Not Match! Quitting ...${NORMAL}"
fi