[RFC PATCH v1 03/10] selftests/landlock: Create 'create' test

[Ivanov Mikhail]

Initiate socket_test.c selftests. Add protocol fixture for tests
with changeable domain/type values. Only most common variants of
protocols (like ipv4-tcp,ipv6-udp, unix) were added.
Add simple socket access right checking test.

Signed-off-by: Ivanov Mikhail <ivanov.mikhail1 at huawei-partners.com>
Reviewed-by: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
---
 .../testing/selftests/landlock/socket_test.c  | 197 ++++++++++++++++++
 1 file changed, 197 insertions(+)
 create mode 100644 tools/testing/selftests/landlock/socket_test.c

diff --git a/tools/testing/selftests/landlock/socket_test.c b/tools/testing/selftests/landlock/socket_test.c
new file mode 100644
index 000000000..525f4f7df
--- /dev/null
+++ b/tools/testing/selftests/landlock/socket_test.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Landlock tests - Socket
+ *
+ * Copyright © 2024 Huawei Tech. Co., Ltd.
+ */
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <linux/landlock.h>
+#include <sched.h>
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+
+#include "common.h"
+
+/* clang-format off */
+
+#define ACCESS_LAST LANDLOCK_ACCESS_SOCKET_CREATE
+
+#define ACCESS_ALL ( \
+	LANDLOCK_ACCESS_SOCKET_CREATE)
+
+/* clang-format on */
+
+struct protocol_variant {
+	int domain;
+	int type;
+};
+
+struct service_fixture {
+	struct protocol_variant protocol;
+};
+
+static void setup_namespace(struct __test_metadata *const _metadata)
+{
+	set_cap(_metadata, CAP_SYS_ADMIN);
+	ASSERT_EQ(0, unshare(CLONE_NEWNET));
+	clear_cap(_metadata, CAP_SYS_ADMIN);
+}
+
+static int socket_variant(const struct service_fixture *const srv)
+{
+	int ret;
+
+	ret = socket(srv->protocol.domain, srv->protocol.type | SOCK_CLOEXEC,
+			 0);
+	if (ret < 0)
+		return -errno;
+	return ret;
+}
+
+FIXTURE(protocol)
+{
+	struct service_fixture srv0;
+};
+
+FIXTURE_VARIANT(protocol)
+{
+	const struct protocol_variant protocol;
+};
+
+FIXTURE_SETUP(protocol)
+{
+	disable_caps(_metadata);
+	self->srv0.protocol = variant->protocol;
+	setup_namespace(_metadata);
+};
+
+FIXTURE_TEARDOWN(protocol)
+{
+}
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, unspec) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_UNSPEC,
+		.type = SOCK_STREAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, unix_stream) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_UNIX,
+		.type = SOCK_STREAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, unix_dgram) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_UNIX,
+		.type = SOCK_DGRAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, ipv4_tcp) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, ipv4_udp) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_INET,
+		.type = SOCK_DGRAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, ipv6_tcp) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_INET6,
+		.type = SOCK_STREAM,
+	},
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, ipv6_udp) {
+	/* clang-format on */
+	.protocol = {
+		.domain = AF_INET6,
+		.type = SOCK_DGRAM,
+	},
+};
+
+static void test_socket_create(struct __test_metadata *const _metadata,
+				  const struct service_fixture *const srv,
+				  const bool deny_create)
+{
+	int fd;
+
+	fd = socket_variant(srv);
+	if (srv->protocol.domain == AF_UNSPEC) {
+		EXPECT_EQ(fd, -EAFNOSUPPORT);
+	} else if (deny_create) {
+		EXPECT_EQ(fd, -EACCES);
+	} else {
+		EXPECT_LE(0, fd)
+		{
+			TH_LOG("Failed to create socket: %s", strerror(errno));
+		}
+		EXPECT_EQ(0, close(fd));
+	}
+}
+
+TEST_F(protocol, create)
+{
+	const struct landlock_ruleset_attr ruleset_attr = {
+		.handled_access_socket = LANDLOCK_ACCESS_SOCKET_CREATE,
+	};
+	const struct landlock_socket_attr create_socket_attr = {
+		.allowed_access = LANDLOCK_ACCESS_SOCKET_CREATE,
+		.domain = self->srv0.protocol.domain,
+		.type = self->srv0.protocol.type,
+	};
+
+	int ruleset_fd;
+
+	/* Allowed create */
+	ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+							sizeof(ruleset_attr), 0);
+	ASSERT_LE(0, ruleset_fd);
+
+	ASSERT_EQ(0,
+			landlock_add_rule(ruleset_fd, LANDLOCK_RULE_SOCKET,
+					&create_socket_attr, 0));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	EXPECT_EQ(0, close(ruleset_fd));
+
+	test_socket_create(_metadata, &self->srv0, false);
+
+	/* Denied create */
+	ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+							sizeof(ruleset_attr), 0);
+	ASSERT_LE(0, ruleset_fd);
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	EXPECT_EQ(0, close(ruleset_fd));
+
+	test_socket_create(_metadata, &self->srv0, true);
+}
+
+TEST_HARNESS_MAIN
-- 
2.34.1