diff --git a/lib/dns/include/dns/name.h b/lib/dns/include/dns/name.h
index b4500f3c43..677ec583e4 100644
--- a/lib/dns/include/dns/name.h
+++ b/lib/dns/include/dns/name.h
@@ -968,6 +968,33 @@ dns_name_downcase(const dns_name_t *source, dns_name_t *name,
  * Note: if source == name, then the result will always be ISC_R_SUCCESS.
  */
 
+isc_result_t
+dns_name_append(dns_name_t *name, const dns_name_t *suffix,
+		isc_buffer_t *target);
+/*%<
+ *	Appends 'suffix' onto 'name'
+ *
+ * Requires:
+ *
+ *\li	'name' is a valid name.
+ *
+ *\li	'suffix' is a valid name.
+ *
+ *\li	'target' is a valid buffer or 'target' is NULL and 'name' has
+ *	a dedicated buffer.
+ *
+ *\li	If 'name' is absolute, 'suffix' must be empty.
+ *
+ * Ensures:
+ *
+ *\li	On success, the used space in target is updated.
+ *
+ * Returns:
+ *\li	#ISC_R_SUCCESS
+ *\li	#ISC_R_NOSPACE
+ *\li	#DNS_R_NAMETOOLONG
+ */
+
 isc_result_t
 dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 		     dns_name_t *name, isc_buffer_t *target);
diff --git a/lib/dns/name.c b/lib/dns/name.c
index 2cd72deebe..6f91e2b05a 100644
--- a/lib/dns/name.c
+++ b/lib/dns/name.c
@@ -1775,6 +1775,45 @@ dns_name_towire2(const dns_name_t *name, dns_compress_t *cctx,
 	return (ISC_R_SUCCESS);
 }
 
+isc_result_t
+dns_name_append(dns_name_t *name, const dns_name_t *suffix,
+		isc_buffer_t *target) {
+	unsigned int length;
+
+	/*
+	 * Append 'suffix' onto 'name'
+	 */
+
+	REQUIRE(VALID_NAME(name));
+	REQUIRE(VALID_NAME(suffix));
+	REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
+		(target == NULL && ISC_BUFFER_VALID(name->buffer)));
+	REQUIRE(!dns_name_isabsolute(name) || suffix->labels == 0);
+
+	if (target == NULL) {
+		target = name->buffer;
+	}
+
+	length = name->length + suffix->length;
+	if (length > DNS_NAME_MAXWIRE) {
+		return (DNS_R_NAMETOOLONG);
+	}
+	if (length > isc_buffer_availablelength(target)) {
+		return (ISC_R_NOSPACE);
+	}
+
+	name->length = length;
+	name->labels += suffix->labels;
+	name->attributes.absolute = suffix->attributes.absolute;
+	isc_buffer_putmem(target, suffix->ndata, suffix->length);
+
+	if (name->offsets != NULL) {
+		set_offsets(name, name->offsets, NULL);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
 isc_result_t
 dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 		     dns_name_t *name, isc_buffer_t *target) {