1 files changed, 69 insertions, 0 deletions
diff --git a/lib/dnssec/nsec.h b/lib/dnssec/nsec.h
new file mode 100644
index 0000000..a173fa5
--- /dev/null
+++ b/lib/dnssec/nsec.h
@@ -0,0 +1,69 @@
+/*  Copyright (C) CZ.NIC, z.s.p.o. <knot-resolver@labs.nic.cz>
+ *  SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include <libknot/packet/pkt.h>
+
+#include "lib/layer/iterate.h"
+
+/**
+ * Check bitmap that child names are contained in the same zone.
+ * @note see RFC6840 4.1.
+ * @param bm      Bitmap from NSEC or NSEC3.
+ * @param bm_size Bitmap size.
+ * @return 0 if they are, >0 if not (abs(ENOENT)), <0 on error.
+ */
+int kr_nsec_children_in_zone_check(const uint8_t *bm, uint16_t bm_size);
+
+/**
+ * Check an NSEC or NSEC3 bitmap for NODATA for a type.
+ * @param bm      Bitmap.
+ * @param bm_size Bitmap size.
+ * @param type    RR type to check.
+ * @param owner   NSEC record owner.
+ * @note This includes special checks for zone cuts, e.g. from RFC 6840 sec. 4.
+ * @return 0, abs(ENOENT) (no proof), kr_error(EINVAL)
+ */
+int kr_nsec_bitmap_nodata_check(const uint8_t *bm, uint16_t bm_size, uint16_t type, const knot_dname_t *owner);
+
+/**
+ * Wildcard answer response check (RFC4035 3.1.3.3).
+ * @param pkt        Packet structure to be processed.
+ * @param section_id Packet section to be processed.
+ * @param sname      Name to be checked.
+ * @return           0 or error code.
+ */
+int kr_nsec_wildcard_answer_response_check(const knot_pkt_t *pkt, knot_section_t section_id,
+                                           const knot_dname_t *sname);
+
+/**
+ * Search for a negative proof for sname+stype among validated NSECs.
+ *
+ * @param rrrs       list of RRs to search; typically kr_request::auth_selected
+ * @param qry_uid    only consider NSECs from this packet, for better efficiency
+ * @return           negative error code, or PKT_NXDOMAIN | PKT_NODATA (both for NXDOMAIN)
+ */
+int kr_nsec_negative(const ranked_rr_array_t *rrrs, uint32_t qry_uid,
+			const knot_dname_t *sname, uint16_t stype);
+
+/**
+ * Referral to unsigned subzone check (RFC4035 5.2).
+ *
+ * @param rrrs       list of RRs to search; typically kr_request::auth_selected
+ * @param qry_uid    only consider NSECs from this packet, for better efficiency
+ * @return           0 or negative error code, in particular DNSSEC_NOT_FOUND
+ */
+int kr_nsec_ref_to_unsigned(const ranked_rr_array_t *rrrs, uint32_t qry_uid,
+				const knot_dname_t *sname);
+
+/**
+ * Checks whether supplied NSEC RR matches the supplied name and type.
+ * @param nsec  NSEC RR.
+ * @param name  Name to be checked.
+ * @param type  Type to be checked.  Only use with NS!  TODO (+copy&paste NSEC3)
+ * @return      0 or error code.
+ */
+int kr_nsec_matches_name_and_type(const knot_rrset_t *nsec,
+				   const knot_dname_t *name, uint16_t type);