Adding support for kdigs out-of-tree json output to dehydrated-nsupdate.

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

2 files changed, 43 insertions, 4 deletions

diff --git a/dehydrated/bin/dehydrated-nsupdate b/dehydrated/bin/dehydrated-nsupdate
index be773f8..0b93145 100755
--- a/dehydrated/bin/dehydrated-nsupdate
+++ b/dehydrated/bin/dehydrated-nsupdate
@@ -46,6 +46,19 @@ if command -v kdig > /dev/null 2>&1
 then
 	# knot-dnsutils
 	DIG="kdig +noidn"
+
+	# out-of-tree json output support
+	if kdig +json > /dev/null 2>&1
+	then
+		DIG="${DIG} +json"
+		KDIG_JSON="true"
+
+		if ! command -v jq > /dev/null 2>&1
+		then
+			echo "'${HOOK}': need jq for knot-dnsutils with json output" >&2
+			exit 1
+		fi
+	fi
 elif command -v dig > /dev/null 2>&1
 then
 	# bind-dnsutils
@@ -79,7 +92,15 @@ do
 done
 
 # find txt record to update
-CNAME="$(${DIG} +nocomments +noquestion "_acme-challenge.${DOMAIN}" 2>&1 | grep -v '^;' | awk '/CNAME/ { print $5 }' | tail -n1)"
+case "${KDIG_JSON}" in
+	true)
+		CNAME="$(${DIG} "_acme-challenge.${DOMAIN}" | jq -r -M '.answer | .[] | .rdata' | tail -n1)"
+		;;
+
+	*)
+		CNAME="$(${DIG} +nocomments +noquestion "_acme-challenge.${DOMAIN}" 2>&1 | grep -v '^;' | awk '/CNAME/ { print $5 }' | tail -n1)"
+		;;
+esac
 
 if [ -n "${CNAME}" ]
 then
@@ -93,11 +114,28 @@ ZONE="${TXT_RECORD}"
 
 while true
 do
-	NAMESERVERS="$(${DIG} +nocomments +noquestion NS "${ZONE}" 2>&1 | grep -v '^;' | awk '/NS/ { print $5 }')"
+	case "${KDIG_JSON}" in
+		true)
+			NAMESERVERS="$(${DIG} NS "${ZONE}" | jq -r -M '.answer | .[] | .rdata')"
+			;;
+
+		*)
+			NAMESERVERS="$(${DIG} +nocomments +noquestion NS "${ZONE}" 2>&1 | grep -v '^;' | awk '/NS/ { print $5 }')"
+			;;
+	esac
 
 	if [ -n "${NAMESERVERS}" ]
 	then
-		ZONE="$(${DIG} +nocomments +noquestion NS "${ZONE}" 2>&1 | grep -v '^;' | awk '/NS/ { print $1 }' | tail -n1)"
+		case "${KDIG_JSON}" in
+			true)
+				ZONE="$(${DIG} NS "${ZONE}" | jq -r -M '.answer | .[] | .rdata' | tail -n1)"
+				;;
+
+			*)
+				ZONE="$(${DIG} +nocomments +noquestion NS "${ZONE}" 2>&1 | grep -v '^;' | awk '/NS/ { print $1 }' | tail -n1)"
+				;;
+		esac
+
 		break
 	else
 		ZONE="$(echo "${ZONE}" | cut -d '.' -f 2-)"
diff --git a/dehydrated/share/man/dehydrated-nsupdate.1.rst b/dehydrated/share/man/dehydrated-nsupdate.1.rst
index b7e02a3..17a6203 100644
--- a/dehydrated/share/man/dehydrated-nsupdate.1.rst
+++ b/dehydrated/share/man/dehydrated-nsupdate.1.rst
@@ -73,7 +73,8 @@ Features
 | **dehydrated-nsupdate** removes records after succesfull verification.
 
 | **bind9-dnsutils and knot-dnsutils support*
-| **dehydrated-nsupdate** works with both nsupdate (bind9) and knsupdate (knot).
+| **dehydrated-nsupdate** works with both nsupdate (bind9) and knsupdate (knot),
+| including support for kdigs out-of-tree json output.
 
 | **IDN handling**
 | **dehydrated-nsupdate** works with IDN domains by not expanding the punycode.