moulti-check-domain

[xavierog]

A Moulti-based tool to inspect a domain name.
Not intended to replace the numerous full-fledged DNS check tools out there.

Screenshot

Requirements

• Moulti
• dig
• timeout
• whois

Usage

moulti-check-domain <domain> <top-level-domain>

Example: moulti-check-domain example org -- note the space instead of a dot.

Code

#!/usr/bin/env bash

export MOULTI_INSTANCE="check-dns-$$"
[ "${MOULTI_RUN}" ] || exec moulti run -- "$0" "$@"

source moulti-functions.bash

moulti_check_requirements awk dig timeout whois

domain="$1"
tld="$2"

function cmdline {
	printf '[#b2b2b2 on #000000][bold yellow]$[/] %s [/]' "$*"
}
function new_step {
	local cmd="$1"; shift
	moulti step add "$@" --top-text="$(cmdline "${cmd}")"
}
function set_cmdline {
	moulti step update "$1" --top-text="$(cmdline "$2")"
}

moulti set --title="check-dns: ${domain}.${tld}"

moulti divider add d_whois --title='WHOIS (RFC 3912)'
new_step "whois ${domain}.${tld}" full_whois --title='WHOIS' --no-auto-scroll
timeout 3 whois "${domain}.${tld}" 2>&1 | moulti pass full_whois &
# It is tempting to offer an abridged version of the WHOIS output. However, a
# brief look at the python-whois project reflects that parsing the WHOIS output
# properly takes WAY more than a mere `grep -P`.

readarray -t all_tld_ns < <(dig +short NS "${tld}" | sort)

moulti divider add d_ns --title='NS: Name Servers'
new_step "dig +noall +authority @[i]tld_ns[/] ${domain}.${tld} IN NS" \
	ns \
	--title="NS for ${domain}.${tld} as reflected by TLD (Top-Level Domain) NS" \
	--max-height=0
{
	fail=''
	prev_response=''
	for tld_ns in "${all_tld_ns[@]}"; do
		set_cmdline ns "dig +noall +authority @[yellow1]${tld_ns}[/] ${domain}.${tld} IN NS"
		response=$(dig +noall +authority "@${tld_ns}" "${domain}.${tld}" IN NS | sort -k 1 -k 5)
		echo "${response}" | sed "s/^/${tld_ns}: /"
		[ "${prev_response}" ] && [ "${response}" != "${prev_response}" ] && fail=1
		prev_response="${response}"
	done
	set_cmdline ns "dig +noall +authority @[i]tld_ns[/] ${domain}.${tld} IN NS"
	[ "${fail}" ] && moulti step update ns --classes='error'
} 2>&1 | moulti pass ns &

new_step "dig +noall +additional @[i]tld_ns[/] ${domain}.${tld} IN NS" \
	glue \
	--title='Glue records' \
	--max-height=0
{
	fail=''
	prev_response=''
	for tld_ns in "${all_tld_ns[@]}"; do
		set_cmdline glue "dig +noall +additional @[yellow1]${tld_ns}[/] ${domain}.${tld} IN NS"
		response=$(dig +noall +additional "@${tld_ns}" "${domain}.${tld}" IN NS | sort -k 1 -k 5)
		[ "${response}" ] || response='no glue records'
		echo "${response}" | sed "s/^/${tld_ns}: /"
		[ "${prev_response}" ] && [ "${response}" != "${prev_response}" ] && fail=1
		prev_response="${response}"
	done
	set_cmdline glue "dig +noall +additional @[i]tld_ns[/] ${domain}.${tld} IN NS"
	[ "${fail}" ] && moulti step update glue --classes='error'
} 2>&1 | moulti pass glue &

readarray -t all_ns < <(dig +noall +authority "${domain}.${tld}" IN NS "@${all_tld_ns[0]}" | awk '{print $NF}' | sort)
moulti divider add d_rr --title='RR: Resource Records'
i=0
for ns in "${all_ns[@]}"; do
	((++i))
	new_step "dig +noall +answer +multiline @${ns} ${domain}.${tld} IN [i]rr_type[/]" \
		"main_rr_${i}" \
		--title="Main RR for ${domain}.${tld} according to NS ${ns}"
	{
		set_cmdline "main_rr_${i}" "dig +noall +answer +multiline @${ns} ${domain}.${tld} IN [yellow1]SOA[/]"
		dig +timeout=3 +noall +answer +multiline "@${ns}" "${domain}.${tld}" IN SOA
		for rr in NS MX A AAAA CNAME TXT CAA; do
			set_cmdline "main_rr_${i}" "dig +noall +answer +multiline @${ns} ${domain}.${tld} IN [yellow1]${rr}[/]"
			dig +timeout=2 +noall +answer "@${ns}" "${domain}.${tld}" IN "${rr}" | sort -k 4,5
		done
		set_cmdline "main_rr_${i}" "dig +noall +answer +multiline @${ns} ${domain}.${tld} IN [i]rr_type[/]"
	} 2>&1 | moulti pass "main_rr_${i}" &
done
wait