unit-tests: Add a unit test for CHILD_SA DELETE collisions

src/libcharon/tests/Makefile.am

@@ -24,6 +24,7 @@ libcharon_tests_LDADD = \
 
 
 exchange_tests_SOURCES = \
+  suites/test_child_delete.c \
   utils/exchange_test_asserts.h utils/exchange_test_asserts.c \
   utils/exchange_test_helper.h utils/exchange_test_helper.c \
   utils/mock_ipsec.h utils/mock_ipsec.c \

src/libcharon/tests/exchange_tests.h

@@ -12,3 +12,5 @@
  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * for more details.
  */
+
+TEST_SUITE(child_delete_suite_create)

src/libcharon/tests/suites/test_child_delete.c

@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2016 Tobias Brunner
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "test_suite.h"
+
+#include <daemon.h>
+#include <tests/utils/exchange_test_helper.h>
+#include <tests/utils/exchange_test_asserts.h>
+#include <tests/utils/sa_asserts.h>
+
+/**
+ * Regular CHILD_SA deletion either initiated by the original initiator or
+ * responder of the IKE_SA.
+ */
+START_TEST(test_regular)
+{
+	ike_sa_t *a, *b;
+
+	if (_i)
+	{	/* responder deletes the CHILD_SA (SPI 2) */
+		exchange_test_helper->establish_sa(exchange_test_helper,
+										   &b, &a);
+	}
+	else
+	{	/* initiator deletes the CHILD_SA (SPI 1) */
+		exchange_test_helper->establish_sa(exchange_test_helper,
+										   &a, &b);
+	}
+	assert_hook_not_called(child_updown);
+	a->delete_child_sa(a, PROTO_ESP, _i+1, FALSE);
+	assert_child_sa_state(a, _i+1, CHILD_DELETING);
+	assert_hook();
+
+	/* INFORMATIONAL { D } --> */
+	assert_hook_updown(child_updown, FALSE);
+	assert_single_payload(IN, PLV2_DELETE);
+	exchange_test_helper->process_message(exchange_test_helper, b, NULL);
+	assert_child_sa_count(b, 0);
+	assert_hook();
+
+	/* <-- INFORMATIONAL { D } */
+	assert_hook_updown(child_updown, FALSE);
+	assert_single_payload(IN, PLV2_DELETE);
+	exchange_test_helper->process_message(exchange_test_helper, a, NULL);
+	assert_child_sa_count(a, 0);
+	assert_hook();
+
+	a->destroy(a);
+	b->destroy(b);
+}
+END_TEST
+
+/**
+ * Both peers initiate the CHILD_SA deletion concurrently and should handle
+ * the collision properly.
+ */
+START_TEST(test_collision)
+{
+	ike_sa_t *a, *b;
+
+	exchange_test_helper->establish_sa(exchange_test_helper,
+									   &a, &b);
+	/* both peers delete the CHILD_SA concurrently */
+	assert_hook_not_called(child_updown);
+	a->delete_child_sa(a, PROTO_ESP, 1, FALSE);
+	assert_child_sa_state(a, 1, CHILD_DELETING);
+	b->delete_child_sa(b, PROTO_ESP, 2, FALSE);
+	assert_child_sa_state(b, 2, CHILD_DELETING);
+	assert_hook();
+
+	/* RFC 7296 says:
+	 *
+	 *   Normally, the response in the INFORMATIONAL exchange will contain
+	 *   Delete payloads for the paired SAs going in the other direction.
+	 *   There is one exception.  If, by chance, both ends of a set of SAs
+	 *   independently decide to close them, each may send a Delete payload
+	 *   and the two requests may cross in the network.  If a node receives a
+	 *   delete request for SAs for which it has already issued a delete
+	 *   request, it MUST delete the outgoing SAs while processing the request
+	 *   and the incoming SAs while processing the response.  In that case,
+	 *   the responses MUST NOT include Delete payloads for the deleted SAs,
+	 *   since that would result in duplicate deletion and could in theory
+	 *   delete the wrong SA.
+	 *
+	 * We don't handle SAs separately so we expect both are still installed,
+	 * but the INFORMATIONAL response should not contain a DELETE payload.
+	 */
+
+	/* INFORMATIONAL { D } --> */
+	assert_hook_not_called(child_updown);
+	assert_single_payload(IN, PLV2_DELETE);
+	exchange_test_helper->process_message(exchange_test_helper, b, NULL);
+	assert_child_sa_state(b, 2, CHILD_DELETING);
+	/* <-- INFORMATIONAL { D } */
+	assert_single_payload(IN, PLV2_DELETE);
+	exchange_test_helper->process_message(exchange_test_helper, a, NULL);
+	assert_child_sa_state(a, 1, CHILD_DELETING);
+	assert_hook();
+
+	/* <-- INFORMATIONAL { } */
+	assert_hook_updown(child_updown, FALSE);
+	assert_message_empty(IN);
+	exchange_test_helper->process_message(exchange_test_helper, a, NULL);
+	assert_child_sa_count(a, 0);
+	assert_hook();
+	/* INFORMATIONAL { } --> */
+	assert_hook_updown(child_updown, FALSE);
+	assert_message_empty(IN);
+	exchange_test_helper->process_message(exchange_test_helper, b, NULL);
+	assert_child_sa_count(b, 0);
+	assert_hook();
+
+	a->destroy(a);
+	b->destroy(b);
+}
+END_TEST
+
+Suite *child_delete_suite_create()
+{
+	Suite *s;
+	TCase *tc;
+
+	s = suite_create("child delete");
+
+	tc = tcase_create("regular");
+	tcase_add_loop_test(tc, test_regular, 0, 2);
+	suite_add_tcase(s, tc);
+
+	tc = tcase_create("collision");
+	tcase_add_test(tc, test_collision);
+	suite_add_tcase(s, tc);
+
+	return s;
+}