From 26f817f574cdf835a4fa6f7d16629d4c1a7f74bc Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Tue, 22 Feb 2022 12:29:41 +1100
Subject: [PATCH] Return ISC_R_NOTIMPLEMENTED rather than ISC_R_UNEXPECTEDEND

If the keydata rdata is shorter that 16 octets it is not out private
keydata type and we have not implemented a tostruct method for it.
---
 lib/dns/include/dns/rdata.h           |  1 -
 lib/dns/rdata/generic/keydata_65533.c | 18 ++++++++++++------
 lib/dns/zone.c                        |  2 +-
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/dns/include/dns/rdata.h b/lib/dns/include/dns/rdata.h
index a6e22e7e59..03298c7c71 100644
--- a/lib/dns/include/dns/rdata.h
+++ b/lib/dns/include/dns/rdata.h
@@ -524,7 +524,6 @@ dns_rdata_tostruct(const dns_rdata_t *rdata, void *target, isc_mem_t *mctx);
  * Result:
  *\li	Success
  *\li	Not Implemented
- *\li	Unexpected end of input
  */
 
 void
diff --git a/lib/dns/rdata/generic/keydata_65533.c b/lib/dns/rdata/generic/keydata_65533.c
index c5670d01ab..bfd0994d13 100644
--- a/lib/dns/rdata/generic/keydata_65533.c
+++ b/lib/dns/rdata/generic/keydata_65533.c
@@ -341,42 +341,48 @@ tostruct_keydata(ARGS_TOSTRUCT) {
 
 	/* Refresh timer */
 	if (sr.length < 4) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->refresh = uint32_fromregion(&sr);
 	isc_region_consume(&sr, 4);
 
 	/* Add hold-down */
 	if (sr.length < 4) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->addhd = uint32_fromregion(&sr);
 	isc_region_consume(&sr, 4);
 
 	/* Remove hold-down */
 	if (sr.length < 4) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->removehd = uint32_fromregion(&sr);
 	isc_region_consume(&sr, 4);
 
 	/* Flags */
 	if (sr.length < 2) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->flags = uint16_fromregion(&sr);
 	isc_region_consume(&sr, 2);
 
 	/* Protocol */
 	if (sr.length < 1) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->protocol = uint8_fromregion(&sr);
 	isc_region_consume(&sr, 1);
 
 	/* Algorithm */
 	if (sr.length < 1) {
-		return (ISC_R_UNEXPECTEDEND);
+		/* Not KEYDATA */
+		return (ISC_R_NOTIMPLEMENTED);
 	}
 	keydata->algorithm = uint8_fromregion(&sr);
 	isc_region_consume(&sr, 1);
diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index ca9bbaec4c..7f9f8edcba 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -4362,7 +4362,7 @@ load_secroots(dns_zone_t *zone, dns_name_t *name, dns_rdataset_t *rdataset) {
 
 		/* Convert rdata to keydata. */
 		result = dns_rdata_tostruct(&rdata, &keydata, NULL);
-		if (result == ISC_R_UNEXPECTEDEND) {
+		if (result == ISC_R_NOTIMPLEMENTED) {
 			continue;
 		}
 		RUNTIME_CHECK(result == ISC_R_SUCCESS);