Add primaries, parental-agents as synonyms

Add back the top blocks 'parental-agents', 'primaries', and 'masters'
to the configuration. Do not document them as so many names for the
same clause is confusing.

This has a slight negative side effect that a top block 'primaries'
can be referred to with a zone statement 'parental-agents' for example,
but that shouldn't be a big issue.

bin/named/config.c

@@ -580,6 +580,9 @@ named_config_getname(isc_mem_t *mctx, const cfg_obj_t *obj,
 		oldlen = newlen;                                    \
 	}
 
+static const char *remotesnames[4] = { "remote-servers", "parental-agents",
+				       "primaries", "masters" };
+
 isc_result_t
 named_config_getipandkeylist(const cfg_obj_t *config, const cfg_obj_t *list,
 			     isc_mem_t *mctx, dns_ipkeylist_t *ipkl) {
@@ -695,17 +698,22 @@ resume:
 				continue;
 			}
 			list = NULL;
-			tresult = named_config_getremotesdef(
-				config, "remote-servers", listname, &list);
+			tresult = ISC_R_NOTFOUND;
+			for (size_t n = 0; n < ARRAY_SIZE(remotesnames); n++) {
+				tresult = named_config_getremotesdef(
+					config, remotesnames[n], listname,
+					&list);
+				if (tresult == ISC_R_SUCCESS) {
+					break;
+				}
+			}
 			if (tresult == ISC_R_NOTFOUND) {
 				cfg_obj_log(addr, ISC_LOG_ERROR,
 					    "remote-servers \"%s\" not found",
 					    listname);
-
-				result = tresult;
-				goto cleanup;
 			}
 			if (tresult != ISC_R_SUCCESS) {
+				result = tresult;
 				goto cleanup;
 			}
 			lists[l++].name = listname;

bin/tests/system/checkconf/bad-duplicate-remote-servers-synonyms.conf

@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+remote-servers duplicate { 1.2.3.4; };
+primaries duplicate { 4.3.2.1; };

bin/tests/system/checkconf/good-multiple-remote-servers-synonyms.conf

@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+remote-servers "one" {
+	1.2.3.4;
+};
+
+parental-agents "two" {
+	1.2.3.5;
+};
+
+primaries "three" {
+	1.2.3.6;
+};
+
+masters "four" {
+	1.2.3.7;
+};

lib/isccfg/check.c

@@ -2113,6 +2113,19 @@ check_remoteserverlists(const cfg_obj_t *cctx, isc_mem_t *mctx) {
 	if (tresult != ISC_R_SUCCESS) {
 		result = tresult;
 	}
+	/* parental-agents, primaries, masters are treated as synonyms */
+	tresult = check_remoteserverlist(cctx, "parental-agents", symtab, mctx);
+	if (tresult != ISC_R_SUCCESS) {
+		result = tresult;
+	}
+	tresult = check_remoteserverlist(cctx, "primaries", symtab, mctx);
+	if (tresult != ISC_R_SUCCESS) {
+		result = tresult;
+	}
+	tresult = check_remoteserverlist(cctx, "masters", symtab, mctx);
+	if (tresult != ISC_R_SUCCESS) {
+		result = tresult;
+	}
 	isc_symtab_destroy(&symtab);
 	return result;
 }
@@ -2381,8 +2394,8 @@ check_tls_definitions(const cfg_obj_t *config, isc_mem_t *mctx) {
 }
 
 static isc_result_t
-get_remoteservers_def(const char *list, const char *name, const cfg_obj_t *cctx,
-		      const cfg_obj_t **ret) {
+get_remotes(const cfg_obj_t *cctx, const char *list, const char *name,
+	    const cfg_obj_t **ret) {
 	isc_result_t result;
 	const cfg_obj_t *obj = NULL;
 	const cfg_listelt_t *elt = NULL;
@@ -2410,6 +2423,26 @@ get_remoteservers_def(const char *list, const char *name, const cfg_obj_t *cctx,
 	return ISC_R_NOTFOUND;
 }
 
+static isc_result_t
+get_remoteservers_def(const char *name, const cfg_obj_t *cctx,
+		      const cfg_obj_t **ret) {
+	isc_result_t result;
+
+	result = get_remotes(cctx, "remote-servers", name, ret);
+	if (result == ISC_R_SUCCESS) {
+		return result;
+	}
+	result = get_remotes(cctx, "primaries", name, ret);
+	if (result == ISC_R_SUCCESS) {
+		return result;
+	}
+	result = get_remotes(cctx, "parental-agents", name, ret);
+	if (result == ISC_R_SUCCESS) {
+		return result;
+	}
+	return get_remotes(cctx, "masters", name, ret);
+}
+
 static isc_result_t
 validate_remotes(const cfg_obj_t *obj, const cfg_obj_t *config,
 		 uint32_t *countp, isc_mem_t *mctx) {
@@ -2515,8 +2548,7 @@ resume:
 		if (tresult == ISC_R_EXISTS) {
 			continue;
 		}
-		tresult = get_remoteservers_def("remote-servers", listname,
-						config, &obj);
+		tresult = get_remoteservers_def(listname, config, &obj);
 		if (tresult != ISC_R_SUCCESS) {
 			if (result == ISC_R_SUCCESS) {
 				result = tresult;

lib/isccfg/namedconf.c

@@ -1143,6 +1143,10 @@ static cfg_clausedef_t namedconf_clauses[] = {
 	{ "masters", &cfg_type_remoteservers,
 	  CFG_CLAUSEFLAG_MULTI | CFG_CLAUSEFLAG_NODOC },
 	{ "options", &cfg_type_options, 0 },
+	{ "parental-agents", &cfg_type_remoteservers,
+	  CFG_CLAUSEFLAG_MULTI | CFG_CLAUSEFLAG_NODOC },
+	{ "primaries", &cfg_type_remoteservers,
+	  CFG_CLAUSEFLAG_MULTI | CFG_CLAUSEFLAG_NODOC },
 	{ "remote-servers", &cfg_type_remoteservers, CFG_CLAUSEFLAG_MULTI },
 #if defined(HAVE_LIBXML2) || defined(HAVE_JSON_C)
 	{ "statistics-channels", &cfg_type_statschannels,