add support for dynamic PTR record

bin/plugins/Makefile.am

@@ -8,8 +8,11 @@ AM_CPPFLAGS +=			\
 
 pkglib_LTLIBRARIES = filter-aaaa.la
 pkglib_LTLIBRARIES += filter-a.la
+pkglib_LTLIBRARIES += dynptrr.la
 
 filter_aaaa_la_SOURCES = filter-aaaa.c
 filter_a_la_SOURCES = filter-a.c
 filter_aaaa_la_LDFLAGS = -avoid-version -module -shared -export-dynamic
 filter_a_la_LDFLAGS = -avoid-version -module -shared -export-dynamic
+dynptrr_la_SOURCES = dynptrr.c
+dynptrr_la_LDFLAGS = -avoid-version -module -shared -export-dynamic

bin/plugins/dynptrr.c

@@ -0,0 +1,167 @@
+/*
+ * 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.
+ */
+
+#include <ns/hooks.h>
+#include <dns/view.h>
+#include <dns/rdatalist.h>
+#include <dns/byaddr.h>
+
+typedef struct dynptrr dynptrr_t;
+struct dynptrr {
+	isc_mem_t *mctx;
+};
+
+static ns_hookresult_t
+dynptrr_nxdomain_begin(void *arg, void *cbdata, isc_result_t *resp) {
+	query_ctx_t *qctx = (query_ctx_t *)arg;
+	isc_mem_t *mctx = qctx->client->view->mctx;
+	dynptrr_t *inst = (dynptrr_t *)cbdata;
+	UNUSED(inst);
+	
+	*resp = ISC_R_UNSET;
+	if (qctx->type != dns_rdatatype_ptr) {
+		return NS_HOOK_CONTINUE;
+	}
+	isc_log_write(NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_HOOKS,
+		      ISC_LOG_DEBUG(1), "dynptrr nxdomain begin");
+
+	dns_message_t *message = qctx->client->message;
+
+	dns_name_t *name = isc_mem_get(mctx, sizeof(*name));
+	dns_rdataset_t *synth = NULL;
+	dns_rdatalist_t *synthlist = NULL;
+	dns_rdata_t *synthdata = NULL;
+
+	dns_name_init(name);
+	dns_name_dup(qctx->client->query.qname, mctx, name);	
+	char n[512];
+	dns_name_format(name, n, 512);
+	isc_log_write(NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_HOOKS,
+			ISC_LOG_DEBUG(1), "dynptrr %s", n);
+
+	dns_message_gettemprdataset(message, &synth);
+	dns_rdataset_init(synth);
+	synth->ttl = 60;
+	synth->rdclass = dns_rdataclass_in;
+	synth->type = dns_rdatatype_ptr;
+
+	dns_message_gettemprdatalist(message, &synthlist);
+	dns_rdatalist_init(synthlist);
+	synthlist->ttl = 60;
+	synthlist->rdclass = dns_rdataclass_in;
+	synthlist->type = dns_rdatatype_ptr;
+
+	dns_message_gettemprdata(message, &synthdata);
+	dns_rdata_init(synthdata);
+	synthdata->rdclass = dns_rdataclass_in;
+	synthdata->type = dns_rdatatype_ptr;
+
+	/*
+	 * It seems that for a ptr type, the data must be the ndata pointer of a
+	 * dns_name_t. (I attempted putting a raw string instead, and it was a
+	 * crash)
+	 */
+	synthdata->data = name->ndata;
+	synthdata->length = name->length;
+
+	ISC_LIST_APPEND(synthlist->rdata, synthdata, link);
+
+	dns_rdatalist_tordataset(synthlist, synth);
+	dns_rdataset_setownercase(synth, name);
+	dns_message_addname(message, name, DNS_SECTION_ANSWER);
+	ISC_LIST_APPEND(name->list, synth, link);
+
+	isc_result_t result = ns_query_done(qctx);
+	*resp = result;
+
+	/* ------------------------------------------------- */
+
+//	isc_netaddr_t peeraddr;
+//	isc_netaddr_fromsockaddr(&peeraddr, &qctx->client->peeraddr);
+//
+//	char createdptrnamed[512];
+//	isc_buffer_t createdptrnameb;
+//	isc_buffer_init(&createdptrnameb, createdptrnamed, 512);
+//
+//	dns_name_t *createdptrname = isc_mem_get(mctx, sizeof(*createdptrname));
+//	dns_name_init(createdptrname);
+//	dns_name_setbuffer(createdptrname, &createdptrnameb);
+//	isc_result_t r = dns_byaddr_createptrname(&peeraddr, createdptrname);
+//	isc_log_write(NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_HOOKS,
+//		      ISC_LOG_DEBUG(1), "dynptrr %s", isc_result_totext(r));
+//	dns_name_format(createdptrname, n, 512);
+//	isc_log_write(NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_HOOKS,
+//			ISC_LOG_DEBUG(1), "dynptrr ptr %s", n);
+//	isc_mem_put(mctx, createdptrname, sizeof(*createdptrname));
+//
+	/* ------------------------------------------------- */
+
+	return NS_HOOK_RETURN;
+}
+
+
+void
+plugin_destroy(void **instp) {
+	REQUIRE(instp && *instp);
+
+	dynptrr_t *inst = *instp;
+	isc_mem_t *mctx = inst->mctx;
+	isc_mem_put(mctx, inst, sizeof(*inst));
+	*instp = NULL;
+
+	printf("dynptrr plugin_destroy\n");
+}
+
+int
+plugin_version(void) {
+	printf("dynptrr plugin_version\n");
+	return NS_PLUGIN_VERSION;
+}
+
+isc_result_t                   
+plugin_register(const char *parameters, const void *cfg, const char *cfg_file,
+                unsigned long cfg_line, isc_mem_t *mctx, void *actx,
+                ns_hooktable_t *hooktable, void **instp) {
+	REQUIRE(cfg);
+	REQUIRE(mctx);
+	REQUIRE(actx);
+	REQUIRE(hooktable);
+	REQUIRE(instp && *instp == NULL);
+
+	printf("dynptrr plugin_register %s %s %ld\n", parameters, cfg_file,
+	       cfg_line);
+
+	dynptrr_t *inst = isc_mem_get(mctx, sizeof(*inst));
+	*inst = (dynptrr_t){ .mctx = mctx };
+	*instp = inst;
+
+	const ns_hook_t testhook = {
+		.action = dynptrr_nxdomain_begin,
+		.action_data = inst 
+	};
+	ns_hook_add(hooktable, mctx, NS_QUERY_NXDOMAIN_BEGIN, &testhook);
+
+	return ISC_R_SUCCESS;
+}
+
+isc_result_t
+plugin_check(const char *parameters, const void *cfg, const char *cfg_file,
+             unsigned long cfg_line, isc_mem_t *mctx, void *actx) {
+	REQUIRE(cfg);
+	REQUIRE(mctx);
+	REQUIRE(actx);
+
+	printf("dynptrr plugin_check %s %s %ld\n", parameters, cfg_file,
+	       cfg_line);
+	return ISC_R_SUCCESS;
+}

bin/tests/system/dynptrr/.gitignore

@@ -0,0 +1,3 @@
+named.conf
+named.memstats
+named.run

bin/tests/system/dynptrr/ns1/example.db

@@ -0,0 +1,25 @@
+; 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.
+
+$TTL	120
+@		SOA	ns.example.  hostmaster.ns.example. ( 1 3600 1200 604800 60 )
+@		NS	ns
+@               MX      10 mx
+
+ns		A	10.53.0.1
+		AAAA	fd92:7065:b8e:ffff::1
+
+a-only		NS	1.0.0.4
+aaaa-only	AAAA	2001:db8::5
+dual		A	1.0.0.6
+dual 		AAAA	2001:db8::6
+mx		A	1.0.0.3
+mx 		AAAA	2001:db8::3

bin/tests/system/dynptrr/ns1/named.conf.in

@@ -0,0 +1,37 @@
+/*
+ * 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.
+ */
+
+options {
+	query-source address 10.53.0.1;
+	port @PORT@;
+	pid-file "named.pid";
+	listen-on { 10.53.0.1; };
+	listen-on-v6 { fd92:7065:b8e:ffff::1; };
+	recursion no;
+};
+
+plugin query "../../../../plugins/.libs/dynptrr.so" {
+};
+
+key rndc_key {
+	secret "1234abcd8765";
+	algorithm @DEFAULT_HMAC@;
+};
+
+controls {
+	inet 10.53.0.1 port @CONTROLPORT@ allow { any; } keys { rndc_key; };
+};
+
+
+zone "." { type primary; file "root.db"; };
+zone "example" { type primary; file "example.db"; };

bin/tests/system/dynptrr/ns1/root.db

@@ -0,0 +1,23 @@
+; 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.
+
+$TTL	120
+@		SOA	ns.utld hostmaster.ns.utld ( 1 3600 1200 604800 60 )
+@		NS	ns.utld
+ns.utld		A	10.53.0.1
+ns.utld		AAAA	fd92:7065:b8e:ffff::1
+;
+
+example		NS	ns.example
+ns.example	A	10.53.0.1
+ns.example	AAAA	fd92:7065:b8e:ffff::1
+
+10.53.0.1	PTR	ns.example

bin/tests/system/dynptrr/setup.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+# 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.
+
+. ../conf.sh
+
+copy_setports ns1/named.conf.in ns1/named.conf

bin/tests/system/dynptrr/tests.sh

@@ -0,0 +1,49 @@
+#!/bin/sh
+
+# 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.
+
+set -e
+
+. ../conf.sh
+
+status=0
+n=0
+
+rm -f dig.out.*
+
+dig_with_opts() {
+  "${DIG}" -p "${PORT}" "${@}"
+}
+
+
+n=$((n + 1))
+echo_i "PTR exists, dynptrr hook is not run ($n)"
+ret=0
+dig_with_opts ptr 10.53.0.1 @10.53.0.1 >dig.out.ns1.test$n || ret=1
+grep "status: NOERROR" dig.out.ns1.test${n} >/dev/null || ret=1
+grep "ns.example" dig.out.ns1.test$n >/dev/null || ret=1
+grep "dynptrr nxdomain begin" ns1/named.run && ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=$((status + ret))
+
+n=$((n + 1))
+echo_i "PTR does not exists, dynptrr hook is run ($n)"
+ret=0
+dig_with_opts ptr 10.53.0.2 @10.53.0.1 >dig.out.ns1.test$n || ret=1
+grep "status: NXDOMAIN" dig.out.ns1.test${n} >/dev/null || ret=1
+grep "dynptrr nxdomain begin" ns1/named.run || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=$((status + ret))
+
+exit 1
+echo_i "exit status: $status"
+[ $status -eq 0 ] || exit 1

bin/tests/system/dynptrr/tests_sh_dynptrr.py

@@ -0,0 +1,23 @@
+# 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.
+
+import pytest
+
+pytestmark = pytest.mark.extra_artifacts(
+    [
+        "managed-keys.bind.jnl",
+        "dig.out.*",
+    ]
+)
+
+
+def test_dynptrr(run_tests_sh):
+    run_tests_sh()