Add unittest file for basic:label

src/basic/label.c

@@ -28,3 +28,7 @@ int label_ops_post(int dir_fd, const char *path) {
 
         return label_ops->post(dir_fd, path);
 }
+
+void label_ops_reset(void) {
+        label_ops = NULL;
+}

src/basic/label.h

@@ -12,3 +12,4 @@ int label_ops_set(const LabelOps *label_ops);
 
 int label_ops_pre(int dir_fd, const char *path, mode_t mode);
 int label_ops_post(int dir_fd, const char *path);
+void label_ops_reset(void);

src/test/meson.build

@@ -113,6 +113,7 @@ simple_tests += files(
         'test-iovec-util.c',
         'test-journal-importer.c',
         'test-kbd-util.c',
+        'test-label.c',
         'test-limits-util.c',
         'test-list.c',
         'test-local-addresses.c',

src/test/test-label.c

@@ -0,0 +1,156 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "errno-util.h"
+#include "fd-util.h"
+#include "fs-util.h"
+#include "label.h"
+#include "path-util.h"
+#include "string-util.h"
+#include "tests.h"
+
+static struct stat buf;
+static int check_path(int dir_fd, const char *path) {
+        assert(path);
+        assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
+
+        if (isempty(path))
+                return -EINVAL;
+
+        /* assume length of pathname is not greater than 40*/
+        if (strlen(path) > 40)
+                return -ENAMETOOLONG;
+
+        /* assume a case where a specific label isn't allowed */
+        if (path_equal(path, "/restricted_directory"))
+                return -EACCES;
+        return 0;
+}
+
+static int pre_labelling_func(int dir_fd, const char *path, mode_t mode) {
+        int r;
+
+        assert(mode != MODE_INVALID);
+        r = check_path(dir_fd, path);
+        if (r < 0)
+                return log_error_errno(r, "Error in pathname =>: %m");
+
+        return 0;
+}
+
+static int post_labelling_func(int dir_fd, const char *path) {
+       int r;
+
+        /* assume label policies that restrict certain labels */
+        r = check_path(dir_fd, path);
+        if (r < 0)
+                return log_error_errno(r, "Error in pathname =>: %m");
+
+        /* Set file data to buf */
+        r = RET_NERRNO(fstatat(dir_fd, path, &buf, 0));
+        if (r < 0)
+                return log_error_errno(r, "Error in getting file status =>: %m");
+
+        return 0; /* on success */
+}
+
+static int get_dir_fd(const char *dir_path, mode_t mode) {
+        /* create a new directory and return its descriptor*/
+        int dir_fd = -EBADF;
+
+        assert(dir_path);
+        dir_fd = RET_NERRNO(open_mkdir_at(AT_FDCWD, dir_path, O_CLOEXEC, mode));
+        if (dir_fd < 0)
+                return log_error_errno(dir_fd, "Error occured while opening directory =>: %m");
+
+        return dir_fd;
+}
+
+static int labelling_op(int dir_fd, const char *text, const char *path, mode_t mode) {
+        /* Write some content into the file */
+        ssize_t count;
+        _cleanup_close_ int write_fd = -EBADF;
+        int r;
+
+        assert(text);
+        assert(mode != MODE_INVALID);
+        r = check_path(dir_fd, path);
+        if (r < 0)
+                return log_error_errno(r, "Error in pathname =>: %m");
+
+        /* Open the file within the directory for writing*/
+        write_fd = RET_NERRNO(openat(dir_fd, path, O_CLOEXEC|O_WRONLY|O_TRUNC|O_CREAT, 0644));
+        if (write_fd < 0)
+                return log_error_errno(write_fd, "Error in opening directory for writing =>: %m");
+
+        /* Write data to the file*/
+        count = RET_NERRNO(write(write_fd, text, strlen(text)));
+        if (count < 0)
+                return log_error_errno(count, "Error occured while opening file for writing =>: %m");
+        return 0;
+}
+
+TEST(label_ops_set) {
+        static const LabelOps test_label_ops = {
+                .pre = NULL,
+                .post = NULL,
+        };
+
+        label_ops_reset();
+        assert_se(label_ops_set(&test_label_ops) == 0);
+        /* attempt to reset label_ops when already set */
+        assert_se(label_ops_set(&test_label_ops) == -EBUSY);
+}
+
+TEST(label_ops_pre) {
+        _cleanup_close_ int fd;
+        static const LabelOps test_label_ops = {
+                .pre = pre_labelling_func,
+                .post = NULL,
+        };
+
+        label_ops_reset();
+        label_ops_set(&test_label_ops);
+        fd = get_dir_fd("file1.txt", 0755);
+        assert_se(label_ops_pre(fd, "file1.txt", 0644) == 0);
+        assert_se(label_ops_pre(fd, "/restricted_directory", 0644) == -EACCES);
+        assert_se(label_ops_pre(fd, "", 0700) == -EINVAL);
+        assert_se(label_ops_pre(fd, "/tmp", 0700) == 0);
+        assert_se(label_ops_pre(fd, "wekrgoierhgoierhqgherhgwklegnlweehgorwfkryrit", 0644) == -ENAMETOOLONG);
+}
+
+TEST(label_ops_post) {
+        _cleanup_close_ int fd = -EBADF;
+        const char *text1, *text2;
+        static const LabelOps test_label_ops = {
+                .pre = NULL,
+                .post = post_labelling_func,
+        };
+
+        label_ops_reset();
+        label_ops_set(&test_label_ops);
+
+        /* Open directory */
+        fd = RET_NERRNO(get_dir_fd("label_test_dir", 0755));
+        text1 = "Add initial texts to file for testing label operations to file1\n";
+
+        assert(labelling_op(fd, text1, "file1.txt", 0644) == 0);
+        assert_se(label_ops_post(fd, "file1.txt") == 0);
+        assert_se(strlen(text1) == (size_t)buf.st_size);
+        text2 = "Add text2 data to file2\n";
+
+        assert(labelling_op(fd, text2, "file2.txt", 0644) == 0);
+        assert_se(label_ops_post(fd, "file2.txt") == 0);
+        assert_se(strlen(text2) == (size_t)buf.st_size);
+        assert_se(label_ops_post(fd, "file3.txt") == -ENOENT);
+        assert_se(label_ops_post(fd, "/abcd") == -ENOENT);
+        assert_se(label_ops_post(fd, "/restricted_directory") == -EACCES);
+        assert_se(label_ops_post(fd, "") == -EINVAL);
+}
+
+DEFINE_TEST_MAIN(LOG_INFO)