[PATCH v7 12/18] seltests/landlock: add tests for connect() hooks
From: Konstantin Meskhidze <hidden>
Date: 2022-08-29 17:05:34
Also in:
linux-security-module, netfilter-devel
Subsystem:
kernel selftest framework, landlock security module, the rest · Maintainers:
Shuah Khan, Mickaël Salaün, Linus Torvalds
Adds selftests for connect socket action.
The first are with no landlock restrictions:
- connect without restrictions for ip4;
- connect without restrictions for ip6;
The second ones are with mixed landlock rules:
- connect with restrictions ip4;
- connect with restrictions ip6;
Signed-off-by: Konstantin Meskhidze <redacted>
---
Changes since v6:
* None.
Changes since v5:
* Adds connect_variant() helper.
* Formats code with clang-format-14.
Changes since v4:
* Adds selftests for IP6 family:
- connect_no_restrictions_ip6.
- connect_with_restrictions_ip6.
* Refactors code with self->port, self->addr4 and
self->addr6 variables.
Changes since v3:
* Split commit.
---
tools/testing/selftests/landlock/net_test.c | 174 ++++++++++++++++++++
1 file changed, 174 insertions(+)
diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
index 79c71fa37ddb..9c3d1e425439 100644
--- a/tools/testing/selftests/landlock/net_test.c
+++ b/tools/testing/selftests/landlock/net_test.c@@ -26,6 +26,9 @@ #define IP_ADDRESS "127.0.0.1" +/* Number pending connections queue to be hold */ +#define BACKLOG 10 + FIXTURE(socket) { uint port[MAX_SOCKET_NUM];
@@ -72,6 +75,19 @@ static int bind_variant(const FIXTURE_VARIANT(socket) *const variant, sizeof(self->addr6[index])); } +static int connect_variant(const FIXTURE_VARIANT(socket) *const variant, + const int sockfd, + const FIXTURE_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;
@@ -177,4 +193,162 @@ TEST_F(socket, bind_with_restrictions) ASSERT_EQ(-1, bind_variant(variant, sockfd, self, 2)); ASSERT_EQ(EACCES, errno); } + +TEST_F(socket, connect_no_restrictions) +{ + int sockfd, new_fd; + pid_t child; + int status; + + /* Creates a server socket. */ + 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)); + + /* Makes listening socket. */ + ASSERT_EQ(0, listen(sockfd, BACKLOG)); + + child = fork(); + ASSERT_LE(0, child); + if (child == 0) { + int child_sockfd; + + /* Closes listening socket for the child. */ + ASSERT_EQ(0, close(sockfd)); + /* Create a stream client socket. */ + child_sockfd = create_socket_variant(variant, SOCK_STREAM); + ASSERT_LE(0, child_sockfd); + + /* Makes connection to the listening socket with port[0]. */ + ASSERT_EQ(0, connect_variant(variant, child_sockfd, self, 0)); + _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE); + return; + } + /* Accepts connection from the child. */ + new_fd = accept(sockfd, NULL, 0); + ASSERT_LE(0, new_fd); + + /* Closes connection. */ + ASSERT_EQ(0, close(new_fd)); + + /* Closes listening socket for the parent. */ + ASSERT_EQ(0, close(sockfd)); + + ASSERT_EQ(child, waitpid(child, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); +} + +TEST_F(socket, connect_with_restrictions) +{ + int new_fd; + int sockfd_1, sockfd_2; + pid_t child_1, child_2; + int status; + + 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_BIND_TCP, + .port = self->port[1], + }; + + 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)); + + /* Enforces the ruleset. */ + enforce_ruleset(_metadata, ruleset_fd); + + /* Creates a server socket 1. */ + sockfd_1 = create_socket_variant(variant, SOCK_STREAM); + ASSERT_LE(0, sockfd_1); + + /* Binds the socket 1 to address with port[0]. */ + ASSERT_EQ(0, bind_variant(variant, sockfd_1, self, 0)); + + /* Makes listening socket 1. */ + ASSERT_EQ(0, listen(sockfd_1, BACKLOG)); + + child_1 = fork(); + ASSERT_LE(0, child_1); + if (child_1 == 0) { + int child_sockfd; + + /* Closes listening socket for the child. */ + ASSERT_EQ(0, close(sockfd_1)); + /* Creates a stream client socket. */ + child_sockfd = create_socket_variant(variant, SOCK_STREAM); + ASSERT_LE(0, child_sockfd); + + /* Makes connection to the listening socket with port[0]. */ + ASSERT_EQ(0, connect_variant(variant, child_sockfd, self, 0)); + _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE); + return; + } + /* Accepts connection from the child 1. */ + new_fd = accept(sockfd_1, NULL, 0); + ASSERT_LE(0, new_fd); + + /* Closes connection. */ + ASSERT_EQ(0, close(new_fd)); + + /* Closes listening socket 1 for the parent. */ + ASSERT_EQ(0, close(sockfd_1)); + + ASSERT_EQ(child_1, waitpid(child_1, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); + + /* Creates a server socket 2. */ + sockfd_2 = create_socket_variant(variant, SOCK_STREAM); + ASSERT_LE(0, sockfd_2); + + /* Binds the socket 2 to address with port[1]. */ + ASSERT_EQ(0, bind_variant(variant, sockfd_2, self, 1)); + + /* Makes listening socket 2. */ + ASSERT_EQ(0, listen(sockfd_2, BACKLOG)); + + child_2 = fork(); + ASSERT_LE(0, child_2); + if (child_2 == 0) { + int child_sockfd; + + /* Closes listening socket for the child. */ + ASSERT_EQ(0, close(sockfd_2)); + /* Creates a stream client socket. */ + child_sockfd = create_socket_variant(variant, SOCK_STREAM); + ASSERT_LE(0, child_sockfd); + + /* Makes connection to the listening socket with port[1]. */ + ASSERT_EQ(-1, connect_variant(variant, child_sockfd, self, 1)); + ASSERT_EQ(EACCES, errno); + _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE); + return; + } + + /* Closes listening socket 2 for the parent. */ + ASSERT_EQ(0, close(sockfd_2)); + + ASSERT_EQ(child_2, waitpid(child_2, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); +} TEST_HARNESS_MAIN --
2.25.1