1 /*
2 * Copyright (c) International Business Machines Corp., 2001
3 * 07/2001 Ported by Wayne Boyer
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20 /*
21 * Test Description:
22 * Verify that, fchown(2) succeeds to change the group of a file specified
23 * by path when called by non-root user with the following constraints,
24 * - euid of the process is equal to the owner of the file.
25 * - the intended gid is either egid, or one of the supplementary gids
26 * of the process.
27 * Also, verify that fchown() clears the setuid/setgid bits set on the file.
28 */
29
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <sys/types.h>
33 #include <sys/stat.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include <string.h>
37 #include <signal.h>
38 #include <grp.h>
39 #include <pwd.h>
40
41 #include "test.h"
42 #include "safe_macros.h"
43 #include "compat_16.h"
44
45 #define FILE_MODE (mode_t)(S_IFREG | S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)
46 #define NEW_PERMS (mode_t)(S_IFREG | S_IRWXU | S_IRWXG | S_ISUID | S_ISGID)
47 #define FCHOWN_PERMS (mode_t)(NEW_PERMS & ~(S_ISUID | S_ISGID))
48 #define TESTFILE "testfile"
49
50 TCID_DEFINE(fchown03);
51 int TST_TOTAL = 1;
52
53 static int fildes;
54 char nobody_uid[] = "nobody";
55 static struct passwd *ltpuser;
56
57 static void setup(void);
58 static void cleanup(void);
59
main(int ac,char ** av)60 int main(int ac, char **av)
61 {
62 struct stat stat_buf;
63 int lc;
64 uid_t user_id;
65 gid_t group_id;
66
67 tst_parse_opts(ac, av, NULL, NULL);
68
69 setup();
70
71 for (lc = 0; TEST_LOOPING(lc); lc++) {
72 tst_count = 0;
73
74 user_id = geteuid();
75 GID16_CHECK((group_id = getegid()), "fchown", cleanup)
76
77 TEST(FCHOWN(cleanup, fildes, -1, group_id));
78
79 if (TEST_RETURN == -1) {
80 tst_resm(TFAIL, "fchown() on %s Fails, errno=%d",
81 TESTFILE, TEST_ERRNO);
82 continue;
83 }
84
85 SAFE_FSTAT(cleanup, fildes, &stat_buf);
86
87 if ((stat_buf.st_uid != user_id) ||
88 (stat_buf.st_gid != group_id)) {
89 tst_resm(TFAIL, "%s: Incorrect "
90 "ownership set, Expected %d %d",
91 TESTFILE, user_id, group_id);
92 continue;
93 }
94
95 if (stat_buf.st_mode != FCHOWN_PERMS) {
96 tst_resm(TFAIL, "%s: Incorrect mode permissions"
97 " %#o, Expected %#o", TESTFILE,
98 stat_buf.st_mode, FCHOWN_PERMS);
99 } else {
100 tst_resm(TPASS, "fchown() on %s succeeds: "
101 "Setuid/gid bits cleared", TESTFILE);
102 }
103 }
104
105 cleanup();
106 tst_exit();
107 }
108
setup(void)109 static void setup(void)
110 {
111 tst_sig(FORK, DEF_HANDLER, cleanup);
112
113 tst_require_root();
114
115 ltpuser = SAFE_GETPWNAM(cleanup, nobody_uid);
116 SAFE_SETEUID(NULL, ltpuser->pw_uid);
117
118 TEST_PAUSE;
119
120 tst_tmpdir();
121
122 fildes = SAFE_OPEN(cleanup, TESTFILE, O_RDWR | O_CREAT, FILE_MODE);
123
124 SAFE_SETEUID(cleanup, 0);
125
126 SAFE_FCHOWN(cleanup, fildes, -1, 0);
127 SAFE_FCHMOD(cleanup, fildes, NEW_PERMS);
128
129 SAFE_SETEGID(cleanup, ltpuser->pw_gid);
130 SAFE_SETEUID(cleanup, ltpuser->pw_uid);
131 }
132
cleanup(void)133 static void cleanup(void)
134 {
135 if (fildes > 0 && close(fildes))
136 tst_resm(TWARN | TERRNO, "close(%s) Failed", TESTFILE);
137
138 tst_rmdir();
139 }
140