From 6f726ae3db00e98f063302363b39fa41a5a7a8d3 Mon Sep 17 00:00:00 2001
From: Alessio Podda <alessio@isc.org>
Date: Tue, 7 Oct 2025 06:00:17 +0200
Subject: [PATCH] Move setresign to rdataset.c and rename it

The setresign method is not diff specific, it only returns the minimum
resign time of an rdataset. Move it to rdataset.c to simplify late
refactoring.
---
 lib/dns/diff.c                 | 37 +-------------------------------
 lib/dns/include/dns/rdataset.h | 13 ++++++++++++
 lib/dns/rdataset.c             | 39 ++++++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 36 deletions(-)

diff --git a/lib/dns/diff.c b/lib/dns/diff.c
index d873c4365b..a3364c433c 100644
--- a/lib/dns/diff.c
+++ b/lib/dns/diff.c
@@ -203,41 +203,6 @@ dns_diff_appendminimal(dns_diff_t *diff, dns_difftuple_t **tuplep) {
 	}
 }
 
-static isc_stdtime_t
-setresign(dns_rdataset_t *modified) {
-	dns_rdata_t rdata = DNS_RDATA_INIT;
-	dns_rdata_rrsig_t sig;
-	int64_t when;
-	isc_result_t result;
-
-	result = dns_rdataset_first(modified);
-	INSIST(result == ISC_R_SUCCESS);
-	dns_rdataset_current(modified, &rdata);
-	(void)dns_rdata_tostruct(&rdata, &sig, NULL);
-	if ((rdata.flags & DNS_RDATA_OFFLINE) != 0) {
-		when = 0;
-	} else {
-		when = dns_time64_from32(sig.timeexpire);
-	}
-	dns_rdata_reset(&rdata);
-
-	result = dns_rdataset_next(modified);
-	while (result == ISC_R_SUCCESS) {
-		dns_rdataset_current(modified, &rdata);
-		(void)dns_rdata_tostruct(&rdata, &sig, NULL);
-		if ((rdata.flags & DNS_RDATA_OFFLINE) != 0) {
-			goto next_rr;
-		}
-		if (when == 0 || dns_time64_from32(sig.timeexpire) < when) {
-			when = dns_time64_from32(sig.timeexpire);
-		}
-	next_rr:
-		dns_rdata_reset(&rdata);
-		result = dns_rdataset_next(modified);
-	}
-	INSIST(result == ISC_R_NOMORE);
-	return (isc_stdtime_t)when;
-}
 
 static void
 getownercase(dns_rdataset_t *rdataset, dns_name_t *name) {
@@ -407,7 +372,7 @@ diff_apply(const dns_diff_t *diff, dns_db_t *db, dns_dbversion_t *ver,
 				     op == DNS_DIFFOP_ADDRESIGN))
 				{
 					isc_stdtime_t resign;
-					resign = setresign(&ardataset);
+					resign = dns_rdataset_minresign(&ardataset);
 					dns_db_setsigningtime(db, &ardataset,
 							      resign);
 				}
diff --git a/lib/dns/include/dns/rdataset.h b/lib/dns/include/dns/rdataset.h
index a03897e764..e2917b8675 100644
--- a/lib/dns/include/dns/rdataset.h
+++ b/lib/dns/include/dns/rdataset.h
@@ -632,6 +632,19 @@ dns_rdataset_getheader(const dns_rdataset_t *rdataset);
  * \li	'rdataset' is a valid rdataset.
  */
 
+isc_stdtime_t
+dns_rdataset_minresign(dns_rdataset_t *rdataset);
+/*%<
+ * Return the minimum resign time from an RRSIG rdataset.
+ *
+ * This function iterates through all RRSIG records in the rdataset
+ * and returns the earliest expiration time, which indicates when
+ * the signatures should be resigned.
+ *
+ * Requires:
+ * \li	'rdataset' is a valid rdataset.
+ */
+
 /*%
  * Returns true if the rdataset is of type 'type', or type RRSIG
  * and covers 'type'.
diff --git a/lib/dns/rdataset.c b/lib/dns/rdataset.c
index c418bed890..533b9b9556 100644
--- a/lib/dns/rdataset.c
+++ b/lib/dns/rdataset.c
@@ -30,6 +30,7 @@
 #include <dns/ncache.h>
 #include <dns/rdata.h>
 #include <dns/rdataset.h>
+#include <dns/time.h>
 #include <dns/types.h>
 
 #define MAX_SHUFFLE 100
@@ -597,3 +598,41 @@ dns_rdataset_getheader(const dns_rdataset_t *rdataset) {
 
 	return NULL;
 }
+
+isc_stdtime_t
+dns_rdataset_minresign(dns_rdataset_t *rdataset) {
+	dns_rdata_t rdata = DNS_RDATA_INIT;
+	dns_rdata_rrsig_t sig;
+	int64_t when;
+	isc_result_t result;
+
+	REQUIRE(DNS_RDATASET_VALID(rdataset));
+
+	result = dns_rdataset_first(rdataset);
+	INSIST(result == ISC_R_SUCCESS);
+	dns_rdataset_current(rdataset, &rdata);
+	(void)dns_rdata_tostruct(&rdata, &sig, NULL);
+	if ((rdata.flags & DNS_RDATA_OFFLINE) != 0) {
+		when = 0;
+	} else {
+		when = dns_time64_from32(sig.timeexpire);
+	}
+	dns_rdata_reset(&rdata);
+
+	result = dns_rdataset_next(rdataset);
+	while (result == ISC_R_SUCCESS) {
+		dns_rdataset_current(rdataset, &rdata);
+		(void)dns_rdata_tostruct(&rdata, &sig, NULL);
+		if ((rdata.flags & DNS_RDATA_OFFLINE) != 0) {
+			goto next_rr;
+		}
+		if (when == 0 || dns_time64_from32(sig.timeexpire) < when) {
+			when = dns_time64_from32(sig.timeexpire);
+		}
+	next_rr:
+		dns_rdata_reset(&rdata);
+		result = dns_rdataset_next(rdataset);
+	}
+	INSIST(result == ISC_R_NOMORE);
+	return (isc_stdtime_t)when;
+}