diff options
Diffstat (limited to 'tools/testing/selftests/landlock/base_test.c')
-rw-r--r-- | tools/testing/selftests/landlock/base_test.c | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/tools/testing/selftests/landlock/base_test.c b/tools/testing/selftests/landlock/base_test.c new file mode 100644 index 000000000000..ca40abe9daa8 --- /dev/null +++ b/tools/testing/selftests/landlock/base_test.c @@ -0,0 +1,266 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Landlock tests - Common user space base + * + * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net> + * Copyright © 2019-2020 ANSSI + */ + +#define _GNU_SOURCE +#include <errno.h> +#include <fcntl.h> +#include <linux/landlock.h> +#include <string.h> +#include <sys/prctl.h> +#include <sys/socket.h> +#include <sys/types.h> + +#include "common.h" + +#ifndef O_PATH +#define O_PATH 010000000 +#endif + +TEST(inconsistent_attr) { + const long page_size = sysconf(_SC_PAGESIZE); + char *const buf = malloc(page_size + 1); + struct landlock_ruleset_attr *const ruleset_attr = (void *)buf; + + ASSERT_NE(NULL, buf); + + /* Checks copy_from_user(). */ + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 0, 0)); + /* The size if less than sizeof(struct landlock_attr_enforce). */ + ASSERT_EQ(EINVAL, errno); + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 1, 0)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, 1, 0)); + /* The size if less than sizeof(struct landlock_attr_enforce). */ + ASSERT_EQ(EFAULT, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, + sizeof(struct landlock_ruleset_attr), 0)); + ASSERT_EQ(EFAULT, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size + 1, 0)); + ASSERT_EQ(E2BIG, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, + sizeof(struct landlock_ruleset_attr), 0)); + ASSERT_EQ(ENOMSG, errno); + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size, 0)); + ASSERT_EQ(ENOMSG, errno); + + /* Checks non-zero value. */ + buf[page_size - 2] = '.'; + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size, 0)); + ASSERT_EQ(E2BIG, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size + 1, 0)); + ASSERT_EQ(E2BIG, errno); + + free(buf); +} + +TEST(abi_version) { + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE, + }; + ASSERT_EQ(1, landlock_create_ruleset(NULL, 0, + LANDLOCK_CREATE_RULESET_VERSION)); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr), + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), + LANDLOCK_CREATE_RULESET_VERSION)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0, + LANDLOCK_CREATE_RULESET_VERSION | 1 << 31)); + ASSERT_EQ(EINVAL, errno); +} + +TEST(inval_create_ruleset_flags) { + const int last_flag = LANDLOCK_CREATE_RULESET_VERSION; + const int invalid_flag = last_flag << 1; + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE, + }; + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0, invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr), + invalid_flag)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), invalid_flag)); + ASSERT_EQ(EINVAL, errno); +} + +TEST(empty_path_beneath_attr) { + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE, + }; + const int ruleset_fd = landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), 0); + + ASSERT_LE(0, ruleset_fd); + + /* Similar to struct landlock_path_beneath_attr.parent_fd = 0 */ + ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH, + NULL, 0)); + ASSERT_EQ(EFAULT, errno); + ASSERT_EQ(0, close(ruleset_fd)); +} + +TEST(inval_fd_enforce) { + ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); + + ASSERT_EQ(-1, landlock_restrict_self(-1, 0)); + ASSERT_EQ(EBADF, errno); +} + +TEST(unpriv_enforce_without_no_new_privs) { + int err; + + drop_caps(_metadata); + err = landlock_restrict_self(-1, 0); + ASSERT_EQ(EPERM, errno); + ASSERT_EQ(err, -1); +} + +TEST(ruleset_fd_io) +{ + struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE, + }; + int ruleset_fd; + char buf; + + drop_caps(_metadata); + ruleset_fd = landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), 0); + ASSERT_LE(0, ruleset_fd); + + ASSERT_EQ(-1, write(ruleset_fd, ".", 1)); + ASSERT_EQ(EINVAL, errno); + ASSERT_EQ(-1, read(ruleset_fd, &buf, 1)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(0, close(ruleset_fd)); +} + +/* Tests enforcement of a ruleset FD transferred through a UNIX socket. */ +TEST(ruleset_fd_transfer) +{ + struct landlock_ruleset_attr ruleset_attr = { + .handled_access_fs = LANDLOCK_ACCESS_FS_READ_DIR, + }; + struct landlock_path_beneath_attr path_beneath_attr = { + .allowed_access = LANDLOCK_ACCESS_FS_READ_DIR, + }; + int ruleset_fd_tx, dir_fd; + union { + /* Aligned ancillary data buffer. */ + char buf[CMSG_SPACE(sizeof(ruleset_fd_tx))]; + struct cmsghdr _align; + } cmsg_tx = {}; + char data_tx = '.'; + struct iovec io = { + .iov_base = &data_tx, + .iov_len = sizeof(data_tx), + }; + struct msghdr msg = { + .msg_iov = &io, + .msg_iovlen = 1, + .msg_control = &cmsg_tx.buf, + .msg_controllen = sizeof(cmsg_tx.buf), + }; + struct cmsghdr *cmsg; + int socket_fds[2]; + pid_t child; + int status; + + drop_caps(_metadata); + + /* Creates a test ruleset with a simple rule. */ + ruleset_fd_tx = landlock_create_ruleset(&ruleset_attr, + sizeof(ruleset_attr), 0); + ASSERT_LE(0, ruleset_fd_tx); + path_beneath_attr.parent_fd = open("/tmp", O_PATH | O_NOFOLLOW | + O_DIRECTORY | O_CLOEXEC); + ASSERT_LE(0, path_beneath_attr.parent_fd); + ASSERT_EQ(0, landlock_add_rule(ruleset_fd_tx, LANDLOCK_RULE_PATH_BENEATH, + &path_beneath_attr, 0)); + ASSERT_EQ(0, close(path_beneath_attr.parent_fd)); + + cmsg = CMSG_FIRSTHDR(&msg); + ASSERT_NE(NULL, cmsg); + cmsg->cmsg_len = CMSG_LEN(sizeof(ruleset_fd_tx)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + memcpy(CMSG_DATA(cmsg), &ruleset_fd_tx, sizeof(ruleset_fd_tx)); + + /* Sends the ruleset FD over a socketpair and then close it. */ + ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, socket_fds)); + ASSERT_EQ(sizeof(data_tx), sendmsg(socket_fds[0], &msg, 0)); + ASSERT_EQ(0, close(socket_fds[0])); + ASSERT_EQ(0, close(ruleset_fd_tx)); + + child = fork(); + ASSERT_LE(0, child); + if (child == 0) { + int ruleset_fd_rx; + + *(char *)msg.msg_iov->iov_base = '\0'; + ASSERT_EQ(sizeof(data_tx), recvmsg(socket_fds[1], &msg, MSG_CMSG_CLOEXEC)); + ASSERT_EQ('.', *(char *)msg.msg_iov->iov_base); + ASSERT_EQ(0, close(socket_fds[1])); + cmsg = CMSG_FIRSTHDR(&msg); + ASSERT_EQ(cmsg->cmsg_len, CMSG_LEN(sizeof(ruleset_fd_tx))); + memcpy(&ruleset_fd_rx, CMSG_DATA(cmsg), sizeof(ruleset_fd_tx)); + + /* Enforces the received ruleset on the child. */ + ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); + ASSERT_EQ(0, landlock_restrict_self(ruleset_fd_rx, 0)); + ASSERT_EQ(0, close(ruleset_fd_rx)); + + /* Checks that the ruleset enforcement. */ + ASSERT_EQ(-1, open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC)); + ASSERT_EQ(EACCES, errno); + dir_fd = open("/tmp", O_RDONLY | O_DIRECTORY | O_CLOEXEC); + ASSERT_LE(0, dir_fd); + ASSERT_EQ(0, close(dir_fd)); + _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE); + return; + } + + ASSERT_EQ(0, close(socket_fds[1])); + + /* Checks that the parent is unrestricted. */ + dir_fd = open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC); + ASSERT_LE(0, dir_fd); + ASSERT_EQ(0, close(dir_fd)); + dir_fd = open("/tmp", O_RDONLY | O_DIRECTORY | O_CLOEXEC); + ASSERT_LE(0, dir_fd); + ASSERT_EQ(0, close(dir_fd)); + + ASSERT_EQ(child, waitpid(child, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); +} + +TEST_HARNESS_MAIN |