Merge branch '1798-reject-master-zones-with-ds-records-at-the-apex' into 'master'

Resolve "Reject master zones with DS records at the apex."

Closes #1798

See merge request isc-projects/bind9!3435

CHANGES

@@ -1,3 +1,7 @@
+5431.	[func]		Reject DS records at the zone apex when loading
+			master files. Log but otherwise ignore attempts to
+			add DS records at the zone apex via UPDATE. [GL #1798]
+
 5430.	[doc]		Update docs - with netmgr we're creating separate
 			socket for each IPv6 interface, just as with IPv4.
 			[GL #1782]

bin/tests/system/checkzone/zones/bad-ds.db

@@ -0,0 +1,4 @@
+example.	0	SOA	. . 0 0 0 0 0
+example.	0 	NS	.
+example. 	0	DNSKEY	257 3 10 AwEAAbqjg7xdvnU2Q/gtLw5LOfr5cDeTRjYuEbkzGrUiVSOSoxcTxuao WS/AFPQHuD8OSLiE/CeZ087JowREXl058rRfae8KMrveY17V0wmKs9N1 F1wf/hRDpXiThlRHWlskp8eSEEIqYrrHgWTesy/xDGIEOFM1gwRo0w8j KdRRJeL2hseTMa+m3rTzrYudUsI0BHLW8PiDUCbG5xgdee8/5YR4847i AAqHIiPJ1Z/IT53OIjMmtv5BUykZ8RYjlJxxX+C+dpRKiK73SQaR3hCB XAYOL9WsDp2/fpmEZpewavkMkdC+j2CX+z27MCS3ASO0AeKK0lcNXwND kgreE+Kr7gc=
+example.	0	DS 	14364 10 2 FD03B2312C8F0FE72C1751EFA1007D743C94EC91594FF0047C23C37CE119BA0C

bin/tests/system/nsupdate/tests.sh

@@ -32,6 +32,8 @@ RNDCCMD="$RNDC -c $SYSTEMTESTTOP/common/rndc.conf -p ${CONTROLPORT} -s"
 status=0
 n=0
 
+nextpartreset ns3/named.run
+
 # wait for zone transfer to complete
 tries=0
 while true; do
@@ -1087,6 +1089,25 @@ then
 echo_i "failed"; status=1
 fi
 
+echo_i "check that DS to the zone apex is ignored ($n)"
+$DIG $DIGOPTS +tcp +norec example DS @10.53.0.3 > dig.out.pre.test$n || ret=1
+grep "status: NOERROR" dig.out.pre.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.pre.test$n > /dev/null || ret=1
+nextpart ns3/named.run > /dev/null
+# specify zone to override the default of adding to parent zone
+$NSUPDATE -d <<END > nsupdate.out-$n 2>&1 || ret=1
+server 10.53.0.3 ${PORT}
+zone example
+update add example 0 in DS 14364 10 2 FD03B2312C8F0FE72C1751EFA1007D743C94EC91594FF0047C23C37CE119BA0C
+send
+END
+msg=": attempt to add a DS record at zone apex ignored"
+nextpart ns3/named.run | grep "$msg" > /dev/null || ret=1
+$DIG $DIGOPTS +tcp +norec example DS @10.53.0.3 > dig.out.post.test$n || ret=1
+grep "status: NOERROR" dig.out.post.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.post.test$n > /dev/null || ret=1
+[ $ret = 0 ] || { echo_i "failed"; status=1; }
+
 if $FEATURETEST --gssapi ; then
   n=`expr $n + 1`
   ret=0

doc/notes/notes-current.rst

@@ -71,6 +71,11 @@ New Features
    statements, to limit the number of records of a particular type
    that can be added to a domain name via dynamic update. [GL #1657]
 
+-  ``named`` and ``named-checkzone`` now reject master zones that
+   have a DS RRset at the zone apex.  Attempts to add DS records
+   at the zone apex via UPDATE will be logged but otherwise ignored.
+   DS records belong in the parent zone, not at the zone apex. [GL #1798]
+
 Feature Changes
 ~~~~~~~~~~~~~~~
 

lib/dns/include/dns/result.h

@@ -154,8 +154,9 @@
 #define DNS_R_BADSIG0		(ISC_RESULTCLASS_DNS + 116)
 #define DNS_R_TOOMANYRECORDS	(ISC_RESULTCLASS_DNS + 117)
 #define DNS_R_VERIFYFAILURE	(ISC_RESULTCLASS_DNS + 118)
+#define DNS_R_ATZONETOP		(ISC_RESULTCLASS_DNS + 119)
 
-#define DNS_R_NRESULTS 119 /*%< Number of results */
+#define DNS_R_NRESULTS 120 /*%< Number of results */
 
 /*
  * DNS wire format rcodes.

lib/dns/master.c

@@ -339,6 +339,13 @@ static unsigned char ip6_arpa_offsets[] = { 0, 4, 9 };
 static dns_name_t const ip6_arpa = DNS_NAME_INITABSOLUTE(ip6_arpa_data,
 							 ip6_arpa_offsets);
 
+static inline bool
+dns_master_isprimary(dns_loadctx_t *lctx) {
+	return ((lctx->options & DNS_MASTER_ZONE) != 0 &&
+		(lctx->options & DNS_MASTER_SLAVE) == 0 &&
+		(lctx->options & DNS_MASTER_KEY) == 0);
+}
+
 static inline isc_result_t
 gettoken(isc_lex_t *lex, unsigned int options, isc_token_t *token, bool eol,
 	 dns_rdatacallbacks_t *callbacks) {
@@ -840,10 +847,7 @@ generate(dns_loadctx_t *lctx, char *range, char *lhs, char *gtype, char *rhs,
 	 * RFC2930: TKEY and TSIG are not allowed to be loaded
 	 * from master files.
 	 */
-	if ((lctx->options & DNS_MASTER_ZONE) != 0 &&
-	    (lctx->options & DNS_MASTER_SLAVE) == 0 &&
-	    dns_rdatatype_ismeta(type))
-	{
+	if (dns_master_isprimary(lctx) && dns_rdatatype_ismeta(type)) {
 		(*callbacks->error)(callbacks, "%s: %s:%lu: meta RR type '%s'",
 				    "$GENERATE", source, line, gtype);
 		result = DNS_R_METATYPE;
@@ -869,11 +873,8 @@ generate(dns_loadctx_t *lctx, char *range, char *lhs, char *gtype, char *rhs,
 			goto error_cleanup;
 		}
 
-		if ((lctx->options & DNS_MASTER_ZONE) != 0 &&
-		    (lctx->options & DNS_MASTER_SLAVE) == 0 &&
-		    (lctx->options & DNS_MASTER_KEY) == 0 &&
-		    !dns_name_issubdomain(owner, lctx->top))
-		{
+		if (dns_master_isprimary(lctx) &&
+		    !dns_name_issubdomain(owner, lctx->top)) {
 			char namebuf[DNS_NAME_FORMATSIZE];
 			dns_name_format(owner, namebuf, sizeof(namebuf));
 			/*
@@ -1541,11 +1542,8 @@ load_text(dns_loadctx_t *lctx) {
 						       callbacks);
 				}
 			}
-			if ((lctx->options & DNS_MASTER_ZONE) != 0 &&
-			    (lctx->options & DNS_MASTER_SLAVE) == 0 &&
-			    (lctx->options & DNS_MASTER_KEY) == 0 &&
-			    !dns_name_issubdomain(new_name, lctx->top))
-			{
+			if (dns_master_isprimary(lctx) &&
+			    !dns_name_issubdomain(new_name, lctx->top)) {
 				char namebuf[DNS_NAME_FORMATSIZE];
 				dns_name_format(new_name, namebuf,
 						sizeof(namebuf));
@@ -1740,8 +1738,7 @@ load_text(dns_loadctx_t *lctx) {
 		 * RFC1123: MD and MF are not allowed to be loaded from
 		 * master files.
 		 */
-		if ((lctx->options & DNS_MASTER_ZONE) != 0 &&
-		    (lctx->options & DNS_MASTER_SLAVE) == 0 &&
+		if (dns_master_isprimary(lctx) &&
 		    (type == dns_rdatatype_md || type == dns_rdatatype_mf))
 		{
 			char typebuf[DNS_RDATATYPE_FORMATSIZE];
@@ -1763,10 +1760,7 @@ load_text(dns_loadctx_t *lctx) {
 		 * RFC2930: TKEY and TSIG are not allowed to be loaded
 		 * from master files.
 		 */
-		if ((lctx->options & DNS_MASTER_ZONE) != 0 &&
-		    (lctx->options & DNS_MASTER_SLAVE) == 0 &&
-		    dns_rdatatype_ismeta(type))
-		{
+		if (dns_master_isprimary(lctx) && dns_rdatatype_ismeta(type)) {
 			char typebuf[DNS_RDATATYPE_FORMATSIZE];
 
 			result = DNS_R_METATYPE;
@@ -1902,6 +1896,30 @@ load_text(dns_loadctx_t *lctx) {
 			}
 		}
 
+		if (dns_rdatatype_atparent(type) &&
+		    dns_master_isprimary(lctx) &&
+		    dns_name_equal(ictx->current, lctx->top))
+		{
+			char namebuf[DNS_NAME_FORMATSIZE];
+			char typebuf[DNS_RDATATYPE_FORMATSIZE];
+
+			dns_name_format(ictx->current, namebuf,
+					sizeof(namebuf));
+			dns_rdatatype_format(type, typebuf, sizeof(typebuf));
+			(*callbacks->error)(
+				callbacks,
+				"%s:%lu: %s record at top of zone (%s)", source,
+				line, typebuf, namebuf);
+			result = DNS_R_ATZONETOP;
+			if (MANYERRS(lctx, result)) {
+				SETRESULT(lctx, result);
+				target = target_ft;
+				continue;
+			} else {
+				goto insist_and_cleanup;
+			}
+		}
+
 		if (type == dns_rdatatype_rrsig || type == dns_rdatatype_sig) {
 			covers = dns_rdata_covers(&rdata[rdcount]);
 		} else {
@@ -1963,8 +1981,7 @@ load_text(dns_loadctx_t *lctx) {
 		}
 
 		if ((type == dns_rdatatype_sig || type == dns_rdatatype_nxt) &&
-		    lctx->warn_tcr && (lctx->options & DNS_MASTER_ZONE) != 0 &&
-		    (lctx->options & DNS_MASTER_SLAVE) == 0)
+		    lctx->warn_tcr && dns_master_isprimary(lctx))
 		{
 			(*callbacks->warn)(callbacks,
 					   "%s:%lu: old style DNSSEC "

lib/dns/result.c

@@ -164,6 +164,7 @@ static const char *text[DNS_R_NRESULTS] = {
 	"SIG(0) in wrong location", /*%< 116 DNS_R_BADSIG0 */
 	"too many records",	    /*%< 117 DNS_R_TOOMANYRECORDS */
 	"verify failure",	    /*%< 118 DNS_R_VERIFYFAILURE */
+	"at top of zone",	    /*%< 119 DNS_R_ATZONETOP */
 };
 
 static const char *ids[DNS_R_NRESULTS] = {
@@ -290,6 +291,7 @@ static const char *ids[DNS_R_NRESULTS] = {
 	"DNS_R_BADSIG0",
 	"DNS_R_TOOMANYRECORDS",
 	"DNS_R_VERIFYFAILURE",
+	"DNS_R_ATZONETOP",
 };
 
 static const char *rcode_text[DNS_R_NRCODERESULTS] = {

lib/ns/update.c

@@ -2969,6 +2969,19 @@ update_action(isc_task_t *task, isc_event_t *event) {
 				soa_serial_changed = true;
 			}
 
+			if (dns_rdatatype_atparent(rdata.type) &&
+			    dns_name_equal(name, zonename)) {
+				char typebuf[DNS_RDATATYPE_FORMATSIZE];
+
+				dns_rdatatype_format(rdata.type, typebuf,
+						     sizeof(typebuf));
+				update_log(client, zone, LOGLEVEL_PROTOCOL,
+					   "attempt to add a %s record at "
+					   "zone apex ignored",
+					   typebuf);
+				continue;
+			}
+
 			if (rdata.type == privatetype) {
 				update_log(client, zone, LOGLEVEL_PROTOCOL,
 					   "attempt to add a private type "