1 files changed, 26 insertions, 0 deletions
diff --git a/src/resolve/dns-type.c b/src/resolve/dns-type.c
index fb8228048d..058d14009a 100644
--- a/src/resolve/dns-type.c
+++ b/src/resolve/dns-type.c
@@ -120,6 +120,32 @@ bool dns_type_may_redirect(uint16_t type) {
                        DNS_TYPE_KEY);
 }
 
+bool dns_type_may_wildcard(uint16_t type) {
+
+        /* The following records may not be expanded from wildcard RRsets */
+
+        if (dns_type_is_pseudo(type))
+                return false;
+
+        return !IN_SET(type,
+                       DNS_TYPE_NSEC3,
+                       DNS_TYPE_SOA,
+
+                       /* Prohibited by https://tools.ietf.org/html/rfc4592#section-4.4 */
+                       DNS_TYPE_DNAME);
+}
+
+bool dns_type_apex_only(uint16_t type) {
+
+        /* Returns true for all RR types that may only appear signed in a zone apex */
+
+        return IN_SET(type,
+                      DNS_TYPE_SOA,
+                      DNS_TYPE_NS,            /* this one can appear elsewhere, too, but not signed */
+                      DNS_TYPE_DNSKEY,
+                      DNS_TYPE_NSEC3PARAM);
+}
+
 bool dns_type_is_dnssec(uint16_t type) {
         return IN_SET(type,
                       DNS_TYPE_DS,