support EDE 13 (Cached Error)

Extended DNS Error 13 (Cached Error) is now returned when the server
answers a message from a cached SERVFAIL.

See RFC 8914 section 4.14.

diff --git a/lib/ns/query.c b/lib/ns/query.c
index 3f7f0935aa73af2b949acf5c3f6940c30cbff7f8..929b2bbbcde3145c7dad7dc8c04bcd6e3a98aab5 100644 (file)
--- a/lib/ns/query.c
+++ b/lib/ns/query.c
@@ -6832,6 +6832,7 @@ ns__query_sfcache(query_ctx_t *qctx) {
                                                                         "0");
                }
 
+               dns_ede_add(&qctx->client->edectx, DNS_EDE_CACHEDERROR, NULL);
                qctx->client->inner.attributes |= NS_CLIENTATTR_NOSETFC;
                QUERY_ERROR(qctx, DNS_R_SERVFAIL);
                return ns_query_done(qctx);