--- /dev/null
+#!/usr/bin/env bash
+
+# check_dnssec_expiry.sh
+#
+# Copyright 2017 by Mario Rimann <mario@rimann.org>
+# Licensed under the permissive MIT license, see LICENSE.md
+#
+# Development of this script was partially sponsored by my
+# employer internezzo, see http://www.internezzo.ch
+#
+# If this script helps you to make your work easier, please consider
+# to give feedback or do something good, see https://rimann.org/support
+
+usage() {
+ cat - >&2 << _EOT_
+usage $0 -z <zone> [-w <warning %>] [-c <critical %>] [-r <resolver>] [-f <always failing domain>]
+
+ -z <zone>
+ specify zone to check
+ -w <critical %>
+ warning time left percentage
+ -c <critical %>
+ critical time left percentage
+ -r <resolver>
+ specify which resolver to use.
+ -f <always failing domain>
+ specify a domain that will always fail DNSSEC.
+ used to test if DNSSEC is supported in used tools.
+ -t <DNS record type to check>
+ specify a DNS record type for calculating the remaining lifetime.
+ For example SOA, A, etc.
+_EOT_
+ exit 255
+}
+
+# Parse the input options
+while getopts ":z:w:c:r:f:h:t:" opt; do
+ case $opt in
+ z)
+ zone=$OPTARG
+ ;;
+ w)
+ warning=$OPTARG
+ ;;
+ c)
+ critical=$OPTARG
+ ;;
+ r)
+ resolver=$OPTARG
+ ;;
+ f)
+ alwaysFailingDomain=$OPTARG
+ ;;
+ t)
+ recordType=$OPTARG
+ ;;
+ h)
+ usage ;;
+ esac
+done
+
+
+# Check if dig is available at all - fail hard if not
+pathToDig=$( which dig )
+if [[ ! -e $pathToDig ]]; then
+ echo "No executable of dig found, cannot proceed without dig. Sorry!"
+ exit 1
+fi
+
+# Check if we got a zone to validate - fail hard if not
+if [[ -z $zone ]]; then
+ echo "Missing zone to test - please provide a zone via the -z parameter."
+ usage
+ exit 3
+fi
+
+# Check if we got warning/critical percentage values, use defaults if not
+if [[ -z $warning ]]; then
+ warning=20
+fi
+if [[ -z $critical ]]; then
+ critical=10
+fi
+
+
+# Use Google's 8.8.8.8 resolver as fallback if none is provided
+if [[ -z $resolver ]]; then
+ resolver="8.8.8.8"
+fi
+
+if [[ -z $alwaysFailingDomain ]]; then
+ alwaysFailingDomain="dnssec-failed.org"
+fi
+
+# Use SOA record type as fallback
+if [[ -z $recordType ]]; then
+ recordType="SOA"
+fi
+
+# Check the resolver to properly validate DNSSEC at all (if he doesn't, every further test is futile and a waste of bandwith)
+checkResolverDoesDnssecValidation=$(dig +nocmd +nostats +noquestion $alwaysFailingDomain @${resolver} | grep "opcode: QUERY" | grep "status: SERVFAIL")
+if [[ -z $checkResolverDoesDnssecValidation ]]; then
+ echo "WARNING: Resolver seems to not validate DNSSEC signatures - going further seems hopeless right now."
+ exit 1
+fi
+
+# Check if the resolver delivers an answer for the domain to test
+checkDomainResolvableWithDnssecEnabledResolver=$(dig +short @${resolver} SOA $zone)
+if [[ -z $checkDomainResolvableWithDnssecEnabledResolver ]]; then
+
+ checkDomainResolvableWithDnssecValidationExplicitelyDisabled=$(dig +short @${resolver} SOA $zone +cd)
+
+ if [[ ! -z $checkDomainResolvableWithDnssecValidationExplicitelyDisabled ]]; then
+ echo "CRITICAL: The domain $zone can be validated without DNSSEC validation - but will fail on resolvers that do validate DNSSEC."
+ exit 2
+ else
+ echo "CRITICAL: The domain $zone cannot be resolved via $resolver as resolver while DNSSEC validation is active."
+ exit 2
+ fi
+fi
+
+# Check if the domain is DNSSEC signed at all
+# (and emerge a WARNING in that case, since this check is about testing DNSSEC being "present" and valid which is not the case for an unsigned zone)
+checkZoneItselfIsSignedAtAll=$( dig $zone @$resolver DS +short )
+if [[ -z $checkZoneItselfIsSignedAtAll ]]; then
+ echo "WARNING: Zone $zone seems to be unsigned itself (= resolvable, but no DNSSEC involved at all)"
+ exit 1
+fi
+
+
+# Check if there are multiple RRSIG responses and check them one after the other
+now=$(date +"%s")
+rrsigEntries=$( dig @$resolver $recordType $zone +dnssec | grep RRSIG )
+if [[ -z $rrsigEntries ]]; then
+ echo "CRITICAL: There is no RRSIG for the SOA of your zone."
+ exit 2
+else
+ while read -r rrsig; do
+ # Get the RRSIG entry and extract the date out of it
+ expiryDateOfSignature=$( echo $rrsig | awk '{print $9}')
+ checkValidityOfExpirationTimestamp=$( echo $expiryDateOfSignature | egrep '[0-9]{14}')
+ if [[ -z $checkValidityOfExpirationTimestamp ]]; then
+ echo "UNKNOWN: Something went wrong while checking the expiration of the RRSIG entry - investigate please".
+ exit 3
+ fi
+
+ inceptionDateOfSignature=$( echo $rrsig | awk '{print $10}')
+ checkValidityOfInceptionTimestamp=$( echo $inceptionDateOfSignature | egrep '[0-9]{14}')
+ if [[ -z $checkValidityOfInceptionTimestamp ]]; then
+ echo "UNKNOWN: Something went wrong while checking the inception date of the RRSIG entry - investigate please".
+ exit 3
+ fi
+
+ # Fiddle out the expiry and inceptiondate of the signature to have a base to do some calculations afterwards
+ expiryDateAsString="${expiryDateOfSignature:0:4}-${expiryDateOfSignature:4:2}-${expiryDateOfSignature:6:2} ${expiryDateOfSignature:8:2}:${expiryDateOfSignature:10:2}:00"
+ expiryDateOfSignatureAsUnixTime=$( date -u -d "$expiryDateAsString" +"%s" 2>/dev/null )
+ if [[ $? -ne 0 ]]; then
+ # if we come to this place, something must have gone wrong converting the date-string. This can happen as e.g. MacOS X and Linux don't behave the same way in this topic...
+ expiryDateOfSignatureAsUnixTime=$( date -j -u -f "%Y-%m-%d %T" "$expiryDateAsString" +"%s" )
+ fi
+ inceptionDateAsString="${inceptionDateOfSignature:0:4}-${inceptionDateOfSignature:4:2}-${inceptionDateOfSignature:6:2} ${inceptionDateOfSignature:8:2}:${inceptionDateOfSignature:10:2}:00"
+ inceptionDateOfSignatureAsUnixTime=$( date -u -d "$inceptionDateAsString" +"%s" 2>/dev/null )
+ if [[ $? -ne 0 ]]; then
+ # if we come to this place, something must have gone wrong converting the date-string. This can happen as e.g. MacOS X and Linux don't behave the same way in this topic...
+ inceptionDateOfSignatureAsUnixTime=$( date -j -u -f "%Y-%m-%d %T" "$inceptionDateAsString" +"%s" )
+ fi
+
+
+ # calculate the remaining lifetime of the signature
+ totalLifetime=$( expr $expiryDateOfSignatureAsUnixTime - $inceptionDateOfSignatureAsUnixTime)
+ remainingLifetimeOfSignature=$( expr $expiryDateOfSignatureAsUnixTime - $now)
+ remainingPercentage=$( expr "100" \* $remainingLifetimeOfSignature / $totalLifetime)
+
+ # store the result of this single RRSIG's check
+ if [[ -z $maxRemainingLifetime || $remainingLifetimeOfSignature -gt $maxRemainingLifetime ]]; then
+ maxRemainingLifetime=$remainingLifetimeOfSignature
+ maxRemainingPercentage=$remainingPercentage
+ fi
+ done <<< "$rrsigEntries"
+fi
+
+
+
+
+# determine if we need to alert, and if so, how loud to cry, depending on warning/critial threshholds provided
+if [[ $maxRemainingPercentage -lt $critical ]]; then
+ echo "CRITICAL: DNSSEC signature for $zone is very short before expiration! ($maxRemainingPercentage% remaining) | sig_lifetime=$maxRemainingLifetime sig_lifetime_percentage=$remainingPercentage%;$warning;$critical"
+ exit 2
+elif [[ $remainingPercentage -lt $warning ]]; then
+ echo "WARNING: DNSSEC signature for $zone is short before expiration! ($maxRemainingPercentage% remaining) | sig_lifetime=$maxRemainingLifetime sig_lifetime_percentage=$remainingPercentage%;$warning;$critical"
+ exit 1
+else
+ echo "OK: DNSSEC signatures for $zone seem to be valid and not expired ($maxRemainingPercentage% remaining) | sig_lifetime=$maxRemainingLifetime sig_lifetime_percentage=$remainingPercentage%;$warning;$critical"
+ exit 0
+fi
projects / perso / Immae / Config / Nix.git / blobdiff