1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2019 by Tomohiro Kusumi. All rights reserved.
23  */
24 
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <sys/types.h>
28 #include <sys/stat.h>
29 #include <unistd.h>
30 #include <fcntl.h>
31 #include <err.h>
32 
33 /* backward compat in case it's not defined */
34 #ifndef O_TMPFILE
35 #define	O_TMPFILE	(020000000|O_DIRECTORY)
36 #endif
37 
38 /*
39  * DESCRIPTION:
40  *	Verify stat(2) for O_TMPFILE file considers umask.
41  *
42  * STRATEGY:
43  *	1. open(2) with O_TMPFILE.
44  *	2. linkat(2).
45  *	3. fstat(2)/stat(2) and verify .st_mode value.
46  */
47 
48 static void
49 test_stat_mode(mode_t mask)
50 {
51 	struct stat st, fst;
52 	int i, fd;
53 	char spath[1024], dpath[1024];
54 	const char *penv[] = {"TESTDIR", "TESTFILE0"};
55 	mode_t masked = 0777 & ~mask;
56 	mode_t mode;
57 
58 	/*
59 	 * Get the environment variable values.
60 	 */
61 	for (i = 0; i < ARRAY_SIZE(penv); i++)
62 		if ((penv[i] = getenv(penv[i])) == NULL)
63 			errx(1, "getenv(penv[%d])", i);
64 
65 	umask(mask);
66 	fd = open(penv[0], O_RDWR|O_TMPFILE, 0777);
67 	if (fd == -1)
68 		err(2, "open(%s)", penv[0]);
69 
70 	if (fstat(fd, &fst) == -1)
71 		err(3, "open");
72 
73 	snprintf(spath, sizeof (spath), "/proc/self/fd/%d", fd);
74 	snprintf(dpath, sizeof (dpath), "%s/%s", penv[0], penv[1]);
75 
76 	unlink(dpath);
77 	if (linkat(AT_FDCWD, spath, AT_FDCWD, dpath, AT_SYMLINK_FOLLOW) == -1)
78 		err(4, "linkat");
79 	close(fd);
80 
81 	if (stat(dpath, &st) == -1)
82 		err(5, "stat");
83 	unlink(dpath);
84 
85 	/* Verify fstat(2) result */
86 	mode = fst.st_mode & 0777;
87 	if (mode != masked)
88 		errx(6, "fstat(2) %o != %o\n", mode, masked);
89 
90 	/* Verify stat(2) result */
91 	mode = st.st_mode & 0777;
92 	if (mode != masked)
93 		errx(7, "stat(2) %o != %o\n", mode, masked);
94 }
95 
96 int
97 main(void)
98 {
99 	fprintf(stdout, "Verify stat(2) for O_TMPFILE file considers umask.\n");
100 
101 	test_stat_mode(0022);
102 	test_stat_mode(0077);
103 
104 	return (0);
105 }
106