1 files changed, 54 insertions, 0 deletions
diff --git a/lib/dns/zonekey.c b/lib/dns/zonekey.c
new file mode 100644
index 0000000..f86c2ca
--- /dev/null
+++ b/lib/dns/zonekey.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+
+#include <stdbool.h>
+
+#include <isc/result.h>
+#include <isc/types.h>
+#include <isc/util.h>
+
+#include <dns/keyvalues.h>
+#include <dns/rdata.h>
+#include <dns/rdatastruct.h>
+#include <dns/types.h>
+#include <dns/zonekey.h>
+
+bool
+dns_zonekey_iszonekey(dns_rdata_t *keyrdata) {
+	isc_result_t result;
+	dns_rdata_dnskey_t key;
+	bool iszonekey = true;
+
+	REQUIRE(keyrdata != NULL);
+
+	result = dns_rdata_tostruct(keyrdata, &key, NULL);
+	if (result != ISC_R_SUCCESS) {
+		return (false);
+	}
+
+	if ((key.flags & DNS_KEYTYPE_NOAUTH) != 0) {
+		iszonekey = false;
+	}
+	if ((key.flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE) {
+		iszonekey = false;
+	}
+	if (key.protocol != DNS_KEYPROTO_DNSSEC &&
+	    key.protocol != DNS_KEYPROTO_ANY)
+	{
+		iszonekey = false;
+	}
+
+	return (iszonekey);
+}