These test suites try to check edge cases for TCP sockets
bind() and connect() actions.
socket:
* bind_no_restrictions: Tests with non-landlocked ipv4 and ipv6 sockets.
* bind_with_restrictions: Tests with mixed landlock rules for ipv4 and
ipv6 sockets.
* connect_no_restrictions: Tests with non-landlocked ipv4 and ipv6 sockets.
* connect_with_restrictions: Tests with mixed landlock rules for ipv4 and
ipv6 sockets.
* connect_afunspec_no_restrictions: Tests with no landlock restrictions
allowing to disconnect already connected socket with AF_UNSPEC socket
family.
* connect_afunspec_with_restrictions: Tests with landlocked process
refusing to disconnect already connected socket.
* ruleset_overlap: Tests with overlapping rules for one port.
* ruleset_expanding: Tests with expanding rulesets in which rules are
gradually added one by one, restricting sockets' connections.
* inval: Tests with invalid user space supplied data:
- out of range ruleset attribute;
- unhandled allowed access;
- zero port value;
- zero access value;
- legitimate access values;
layout1:
* with_net: Tests with network bind() socket action within
filesystem directory access test.
Test coverage for security/landlock is 94.3% of 920 lines according
to gcc/gcov-11.
Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@xxxxxxxxxx>
---
Changes since v7:
* Squashes all selftest commits.
* Adds fs test with network bind() socket action.
* Minor fixes.
---
security/landlock/ruleset.h | 2 -
tools/testing/selftests/landlock/config | 4 +
tools/testing/selftests/landlock/fs_test.c | 65 ++
tools/testing/selftests/landlock/net_test.c | 823 ++++++++++++++++++++
4 files changed, 892 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/landlock/net_test.c
diff --git a/security/landlock/ruleset.h b/security/landlock/ruleset.h
index f272d2cd518c..ee1a02a404ce 100644
--- a/security/landlock/ruleset.h
+++ b/security/landlock/ruleset.h
@@ -264,7 +264,6 @@ landlock_add_fs_access_mask(struct landlock_ruleset *const ruleset,
/* Should already be checked in sys_landlock_create_ruleset(). */
WARN_ON_ONCE(fs_access_mask != fs_mask);
- // TODO: Add tests to check "|=" and not "="
ruleset->access_masks[layer_level] |=
(fs_mask << LANDLOCK_SHIFT_ACCESS_FS);
}
@@ -278,7 +277,6 @@ landlock_add_net_access_mask(struct landlock_ruleset *const ruleset,
/* Should already be checked in sys_landlock_create_ruleset(). */
WARN_ON_ONCE(net_access_mask != net_mask);
- // TODO: Add tests to check "|=" and not "="
ruleset->access_masks[layer_level] |=
(net_mask << LANDLOCK_SHIFT_ACCESS_NET);
}
diff --git a/tools/testing/selftests/landlock/config b/tools/testing/selftests/landlock/config
index 0f0a65287bac..71f7e9a8a64c 100644
--- a/tools/testing/selftests/landlock/config
+++ b/tools/testing/selftests/landlock/config
@@ -1,3 +1,7 @@
+CONFIG_INET=y
+CONFIG_IPV6=y
+CONFIG_NET=y
+CONFIG_NET_NS=y
CONFIG_OVERLAY_FS=y
CONFIG_SECURITY_LANDLOCK=y
CONFIG_SECURITY_PATH=y
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 20c1ac8485f1..5c52da1a5a69 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -8,14 +8,17 @@
*/
#define _GNU_SOURCE
+#include <arpa/inet.h>
#include <fcntl.h>
#include <linux/landlock.h>
+#include <netinet/in.h>
#include <sched.h>
#include <string.h>
#include <sys/capability.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/sendfile.h>
+#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <unistd.h>
@@ -4366,4 +4369,66 @@ TEST_F_FORK(layout2_overlay, same_content_different_file)
}
}
+#define IP_ADDRESS "127.0.0.1"
+
+TEST_F_FORK(layout1, with_net)
+{
+ int sockfd;
+ int sock_port = 15000;
+ struct sockaddr_in addr4;
+
+ addr4.sin_family = AF_INET;
+ addr4.sin_port = htons(sock_port);
+ addr4.sin_addr.s_addr = inet_addr(IP_ADDRESS);
+ memset(&addr4.sin_zero, '\0', 8);
+
+ const struct rule rules[] = {
+ {
+ .path = dir_s1d2,
+ .access = ACCESS_RO,
+ },
+ {},
+ };
+
+ struct landlock_ruleset_attr ruleset_attr_net = {
+ .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ };
+ struct landlock_net_service_attr net_service = {
+ .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
+
+ .port = sock_port,
+ };
+
+ /* Creates ruleset for network access. */
+ const int ruleset_fd_net = landlock_create_ruleset(
+ &ruleset_attr_net, sizeof(ruleset_attr_net), 0);
+ ASSERT_LE(0, ruleset_fd_net);
+
+ /* Adds a network rule. */
+ ASSERT_EQ(0,
+ landlock_add_rule(ruleset_fd_net, LANDLOCK_RULE_NET_SERVICE,
+ &net_service, 0));
+
+ enforce_ruleset(_metadata, ruleset_fd_net);
+ ASSERT_EQ(0, close(ruleset_fd_net));
+
+ const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
+ ASSERT_LE(0, ruleset_fd);
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Tests on a directory with the network rule loaded. */
+ ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY));
+ ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
+
+ sockfd = socket(AF_INET, SOCK_STREAM | SOCK_CLOEXEC, 0);
+ ASSERT_LE(0, sockfd);
+ /* Binds a socket to port 15000. */
+ ASSERT_EQ(0, bind(sockfd, &addr4, sizeof(addr4)));
+
+ /* Closes bounded socket. */
+ ASSERT_EQ(0, close(sockfd));
+}
+
TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
new file mode 100644
index 000000000000..d1548bd7ab60
--- /dev/null
+++ b/tools/testing/selftests/landlock/net_test.c
@@ -0,0 +1,823 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Landlock tests - Network
+ *
+ * Copyright (C) 2022 Huawei Tech. Co., Ltd.
+ */
+
+#define _GNU_SOURCE
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/landlock.h>
+#include <netinet/in.h>
+#include <sched.h>
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include "common.h"
+
+#define MAX_SOCKET_NUM 10
+
+#define SOCK_PORT_START 3470
+#define SOCK_PORT_ADD 10
+
+#define IP_ADDRESS "127.0.0.1"
+
+/* Number pending connections queue to be hold. */
+#define BACKLOG 10
+
+const struct sockaddr addr_unspec = { .sa_family = AF_UNSPEC };
+
+/* Invalid attribute, out of landlock network access range. */
+#define LANDLOCK_INVAL_ATTR 7
+
+FIXTURE(socket)
+{
+ uint port[MAX_SOCKET_NUM];
+ struct sockaddr_in addr4[MAX_SOCKET_NUM];
+ struct sockaddr_in6 addr6[MAX_SOCKET_NUM];
+};
+
+/* struct _fixture_variant_socket */
+FIXTURE_VARIANT(socket)
+{
+ const bool is_ipv4;
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(socket, ipv4) {
+ /* clang-format on */
+ .is_ipv4 = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(socket, ipv6) {
+ /* clang-format on */
+ .is_ipv4 = false,
+};
+
+static int
+create_socket_variant(const struct _fixture_variant_socket *const variant,
+ const int type)
+{
+ if (variant->is_ipv4)
+ return socket(AF_INET, type | SOCK_CLOEXEC, 0);
+ else
+ return socket(AF_INET6, type | SOCK_CLOEXEC, 0);
+}
+
+static int bind_variant(const struct _fixture_variant_socket *const variant,
+ const int sockfd,
+ const struct _test_data_socket *const self,
+ const size_t index)
+{
+ if (variant->is_ipv4)
+ return bind(sockfd, &self->addr4[index],
+ sizeof(self->addr4[index]));
+ else
+ return bind(sockfd, &self->addr6[index],
+ sizeof(self->addr6[index]));
+}
+
+static int connect_variant(const struct _fixture_variant_socket *const variant,
+ const int sockfd,
+ const struct _test_data_socket *const self,
+ const size_t index)
+{
+ if (variant->is_ipv4)
+ return connect(sockfd, &self->addr4[index],
+ sizeof(self->addr4[index]));
+ else
+ return connect(sockfd, &self->addr6[index],
+ sizeof(self->addr6[index]));
+}
+
+FIXTURE_SETUP(socket)
+{
+ int i;
+
+ /* Creates IPv4 socket addresses. */
+ for (i = 0; i < MAX_SOCKET_NUM; i++) {
+ self->port[i] = SOCK_PORT_START + SOCK_PORT_ADD * i;
+ self->addr4[i].sin_family = AF_INET;
+ self->addr4[i].sin_port = htons(self->port[i]);
+ self->addr4[i].sin_addr.s_addr = inet_addr(IP_ADDRESS);
+ memset(&(self->addr4[i].sin_zero), '\0', 8);
+ }
+
+ /* Creates IPv6 socket addresses. */
+ for (i = 0; i < MAX_SOCKET_NUM; i++) {
+ self->port[i] = SOCK_PORT_START + SOCK_PORT_ADD * i;
+ self->addr6[i].sin6_family = AF_INET6;
+ self->addr6[i].sin6_port = htons(self->port[i]);
+ inet_pton(AF_INET6, IP_ADDRESS, &(self->addr6[i].sin6_addr));
+ }
+
+ set_cap(_metadata, CAP_SYS_ADMIN);
+ ASSERT_EQ(0, unshare(CLONE_NEWNET));
+ ASSERT_EQ(0, system("ip link set dev lo up"));
+ clear_cap(_metadata, CAP_SYS_ADMIN);
+}
+
+FIXTURE_TEARDOWN(socket)
+{
+}
+
+TEST_F_FORK(socket, bind_no_restrictions)
+{
+ int sockfd;
+
+ sockfd = create_socket_variant(variant, SOCK_STREAM);
+ ASSERT_LE(0, sockfd);
+
+ /* Binds a socket to port[0]. */
+ ASSERT_EQ(0, bind_variant(variant, sockfd, self, 0));
+
+ ASSERT_EQ(0, close(sockfd));
+}
+
+TEST_F_FORK(socket, bind_with_restrictions)
+{
+ int sockfd;
+
+ 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 |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .port = self->port[0],
+ };
+ struct landlock_net_service_attr net_service_2 = {
+ .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .port = self->port[1],
+ };
+ struct landlock_net_service_attr net_service_3 = {
+ .allowed_access = 0,
+ .port = self->port[2],
+ };
+
+ const int ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allows connect and 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 deny bind operations to the port[1] socket. */
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
+ &net_service_2, 0));
+ /*
+ * Empty allowed_access (i.e. deny rules) are ignored in network actions
+ * for port[2] socket.
+ */
+ ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
+ &net_service_3, 0));
+ ASSERT_EQ(ENOMSG, errno);
+
+ /* Enforces the ruleset. */
+ enforce_ruleset(_metadata, ruleset_fd);
+
+ sockfd = create_socket_variant(variant, SOCK_STREAM);
+ ASSERT_LE(0, sockfd);
+ /* Binds a socket to port[0]. */
+ ASSERT_EQ(0, bind_variant(variant, sockfd, self, 0));
+
+ /* Closes bounded socket. */
+ ASSERT_EQ(0, close(sockfd));
+
+ sockfd = create_socket_variant(variant, SOCK_STREAM);
+ ASSERT_LE(0, sockfd);
+ /* Binds a socket to port[1]. */
+ ASSERT_EQ(-1, bind_variant(variant, sockfd, self, 1));
+ ASSERT_EQ(EACCES, errno);
+
+ sockfd = create_socket_variant(variant, SOCK_STREAM);
+ ASSERT_LE(0, sockfd);
+ /* Binds a socket to port[2]. */
+ ASSERT_EQ(-1, bind_variant(variant, sockfd, self, 2));
+ ASSERT_EQ(EACCES, errno);
