[PATCH v7 14/18] seltests/landlock: add rules overlapping test

[Konstantin Meskhidze]

This patch adds overlapping rules for one port. First rule adds just
bind() access right for a port. The second one adds both bind() and
connect() access rights for the same port.

Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
---

Changes since v6:
* None.

Changes since v5:
* Formats code with clang-format-14.

Changes since v4:
* Refactors code with self->port, self->addr4 variables.

Changes since v3:
* Adds ruleset_overlap test.

---
 tools/testing/selftests/landlock/net_test.c | 89 +++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
index 40aef7c683af..b3b38745f4eb 100644
--- a/tools/testing/selftests/landlock/net_test.c
+++ b/tools/testing/selftests/landlock/net_test.c
@@ -464,4 +464,93 @@ TEST_F(socket, connect_afunspec_with_restictions)
 	ASSERT_EQ(1, WIFEXITED(status));
 	ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status));
 }
+
+TEST_F(socket, ruleset_overlap)
+{
+	int sockfd;
+	int one = 1;
+
+	struct landlock_ruleset_attr ruleset_attr = {
+		.handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
+				      LANDLOCK_ACCESS_NET_CONNECT_TCP,
+	};
+	struct landlock_net_service_attr net_service_1 = {
+		.allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
+
+		.port = self->port[0],
+	};
+
+	struct landlock_net_service_attr net_service_2 = {
+		.allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
+				  LANDLOCK_ACCESS_NET_CONNECT_TCP,
+
+		.port = self->port[0],
+	};
+
+	int ruleset_fd =
+		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+	ASSERT_LE(0, ruleset_fd);
+
+	/* Allows bind operations to the port[0] socket. */
+	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
+				       &net_service_1, 0));
+	/* Allows connect and bind operations to the port[0] socket. */
+	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
+				       &net_service_2, 0));
+
+	/* Enforces the ruleset. */
+	enforce_ruleset(_metadata, ruleset_fd);
+
+	/* Creates a server socket. */
+	sockfd = create_socket_variant(variant, SOCK_STREAM);
+	ASSERT_LE(0, sockfd);
+	/* Allows to reuse of local address. */
+	ASSERT_EQ(0, setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &one,
+				sizeof(one)));
+
+	/* Binds the socket to address with port[0]. */
+	ASSERT_EQ(0, bind_variant(variant, sockfd, self, 0));
+
+	/* Makes connection to socket with port[0]. */
+	ASSERT_EQ(0, connect_variant(variant, sockfd, self, 0));
+
+	/* Closes socket. */
+	ASSERT_EQ(0, close(sockfd));
+
+	/* Creates another ruleset layer. */
+	ruleset_fd =
+		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+	ASSERT_LE(0, ruleset_fd);
+
+	/*
+	 * Allows bind operations to the port[0] socket in
+	 * the new ruleset layer.
+	 */
+	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
+				       &net_service_1, 0));
+
+	/* Enforces the new ruleset. */
+	enforce_ruleset(_metadata, ruleset_fd);
+
+	/* Creates a server socket. */
+	sockfd = create_socket_variant(variant, SOCK_STREAM);
+	ASSERT_LE(0, sockfd);
+	/* Allows to reuse of local address. */
+	ASSERT_EQ(0, setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &one,
+				sizeof(one)));
+
+	/* Binds the socket to address with port[0]. */
+	ASSERT_EQ(0, bind_variant(variant, sockfd, self, 0));
+
+	/*
+	 * Forbids to connect the socket to address with port[0],
+	 * cause just one ruleset layer has connect() access rule.
+	 */
+	ASSERT_EQ(-1, connect_variant(variant, sockfd, self, 0));
+	ASSERT_EQ(EACCES, errno);
+
+	/* Closes socket. */
+	ASSERT_EQ(0, close(sockfd));
+}
+
 TEST_HARNESS_MAIN
--
2.25.1