From 60bd3bc0516dc1b773ca912cc78fb49c31f5f9e5 Mon Sep 17 00:00:00 2001
From: Matthijs Mekking <matthijs@isc.org>
Date: Thu, 10 Oct 2024 13:40:45 +0200
Subject: [PATCH] Revert "fix: chg: Improve performance when looking for the
 closest encloser"

The 9.18 code does not have the rbtdb refactoring. Rather than
backporting from MR !9611, this reverts directly from commit
5d81a258e3c7988c9505bba9071e6db9ff327399.
---
 bin/tests/system/dnssec/tests.sh |  4 ++--
 lib/dns/include/dns/db.h         |  1 -
 lib/dns/rbtdb.c                  |  6 +-----
 lib/ns/query.c                   | 20 ++++----------------
 4 files changed, 7 insertions(+), 24 deletions(-)

diff --git a/bin/tests/system/dnssec/tests.sh b/bin/tests/system/dnssec/tests.sh
index 6ef6b1d84e..c7b1c3aab8 100644
--- a/bin/tests/system/dnssec/tests.sh
+++ b/bin/tests/system/dnssec/tests.sh
@@ -386,9 +386,9 @@ status=$((status + ret))
 
 echo_i "checking negative validation NXDOMAIN NSEC3 ($n)"
 ret=0
-dig_with_opts +noauth a.b.c.d.e.f.g.h.i.j.nsec3.example. \
+dig_with_opts +noauth q.nsec3.example. \
   @10.53.0.3 a >dig.out.ns3.test$n || ret=1
-dig_with_opts +noauth a.b.c.d.e.f.g.h.i.j.nsec3.example. \
+dig_with_opts +noauth q.nsec3.example. \
   @10.53.0.4 a >dig.out.ns4.test$n || ret=1
 digcomp dig.out.ns3.test$n dig.out.ns4.test$n || ret=1
 grep "flags:.*ad.*QUERY" dig.out.ns4.test$n >/dev/null || ret=1
diff --git a/lib/dns/include/dns/db.h b/lib/dns/include/dns/db.h
index 5cc563884d..07ff9a43d5 100644
--- a/lib/dns/include/dns/db.h
+++ b/lib/dns/include/dns/db.h
@@ -244,7 +244,6 @@ struct dns_dbonupdatelistener {
 #define DNS_DBFIND_FORCENSEC3	0x0080
 #define DNS_DBFIND_ADDITIONALOK 0x0100
 #define DNS_DBFIND_NOZONECUT	0x0200
-#define DNS_DBFIND_WANTPARTIAL	0x0400
 
 /*
  * DNS_DBFIND_STALEOK: This flag is set when BIND fails to refresh a RRset due
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index bb184f7ed8..5c2f0b252d 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -4134,11 +4134,7 @@ zone_find(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
 						: DNS_R_NXDOMAIN;
 			}
 		} else {
-			bool wantpartial = (options & DNS_DBFIND_WANTPARTIAL) !=
-					   0;
-			result = active	       ? DNS_R_EMPTYNAME
-				 : wantpartial ? DNS_R_PARTIALMATCH
-					       : DNS_R_NXDOMAIN;
+			result = active ? DNS_R_EMPTYNAME : DNS_R_NXDOMAIN;
 		}
 		goto tree_exit;
 	} else if (result != ISC_R_SUCCESS) {
diff --git a/lib/ns/query.c b/lib/ns/query.c
index 0d5274226c..58a9d436fc 100644
--- a/lib/ns/query.c
+++ b/lib/ns/query.c
@@ -11569,7 +11569,6 @@ again:
 		 * Find the closest encloser.
 		 */
 		dns_name_copy(name, cname);
-		bool once = true;
 		while (result == DNS_R_NXDOMAIN) {
 			labels = dns_name_countlabels(cname) - 1;
 			/*
@@ -11579,21 +11578,10 @@ again:
 				goto cleanup;
 			}
 			dns_name_split(cname, labels, NULL, cname);
-			result = dns_db_findext(
-				qctx->db, cname, qctx->version,
-				dns_rdatatype_nsec,
-				options | (once ? DNS_DBFIND_WANTPARTIAL : 0),
-				0, NULL, fname, &cm, &ci, NULL, NULL);
-			if (result == DNS_R_PARTIALMATCH && once) {
-				unsigned int flabels =
-					dns_name_countlabels(fname);
-				if (labels > flabels + 1) {
-					dns_name_split(cname, flabels + 1, NULL,
-						       cname);
-				}
-				result = DNS_R_NXDOMAIN;
-			}
-			once = false;
+			result = dns_db_findext(qctx->db, cname, qctx->version,
+						dns_rdatatype_nsec, options, 0,
+						NULL, fname, &cm, &ci, NULL,
+						NULL);
 		}
 		/*
 		 * Add closest (provable) encloser NSEC3.