1 /*
2 * Copyright (c) Kerlabs 2008.
3 * Copyright (c) International Business Machines Corp., 2008
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
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Created by Renaud Lottiaux
20 */
21
22 /*
23 * Check if setreuid behaves correctly with file permissions.
24 * The test creates a file as ROOT with permissions 0644, does a setreuid
25 * and then tries to open the file with RDWR permissions.
26 * The same test is done in a fork to check if new UIDs are correctly
27 * passed to the son.
28 */
29
30 #include <errno.h>
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 #include <sys/wait.h>
34 #include <fcntl.h>
35 #include <unistd.h>
36 #include <pwd.h>
37
38 #include "test.h"
39 #include "compat_16.h"
40
41 TCID_DEFINE(setreuid07);
42 int TST_TOTAL = 1;
43
44 static char testfile[256] = "";
45 static struct passwd *ltpuser;
46
47 static int fd = -1;
48
49 static void setup(void);
50 static void cleanup(void);
51 static void do_master_child(void);
52
main(int ac,char ** av)53 int main(int ac, char **av)
54 {
55 pid_t pid;
56
57 tst_parse_opts(ac, av, NULL, NULL);
58
59 setup();
60
61 pid = FORK_OR_VFORK();
62 if (pid < 0)
63 tst_brkm(TBROK, cleanup, "Fork failed");
64
65 if (pid == 0)
66 do_master_child();
67
68 tst_record_childstatus(cleanup, pid);
69
70 cleanup();
71 tst_exit();
72 }
73
do_master_child(void)74 static void do_master_child(void)
75 {
76 int lc;
77 int pid;
78 int status;
79
80 for (lc = 0; TEST_LOOPING(lc); lc++) {
81 int tst_fd;
82
83 tst_count = 0;
84
85 if (SETREUID(NULL, 0, ltpuser->pw_uid) == -1) {
86 perror("setreuid failed");
87 exit(TFAIL);
88 }
89
90 /* Test 1: Check the process with new uid cannot open the file
91 * with RDWR permissions.
92 */
93 TEST(tst_fd = open(testfile, O_RDWR));
94
95 if (TEST_RETURN != -1) {
96 printf("open succeeded unexpectedly\n");
97 close(tst_fd);
98 exit(TFAIL);
99 }
100
101 if (TEST_ERRNO == EACCES) {
102 printf("open failed with EACCES as expected\n");
103 } else {
104 perror("open failed unexpectedly");
105 exit(TFAIL);
106 }
107
108 /* Test 2: Check a son process cannot open the file
109 * with RDWR permissions.
110 */
111 pid = FORK_OR_VFORK();
112 if (pid < 0)
113 tst_brkm(TBROK, cleanup, "Fork failed");
114
115 if (pid == 0) {
116 int tst_fd2;
117
118 /* Test to open the file in son process */
119 TEST(tst_fd2 = open(testfile, O_RDWR));
120
121 if (TEST_RETURN != -1) {
122 printf("call succeeded unexpectedly\n");
123 close(tst_fd2);
124 exit(TFAIL);
125 }
126
127 if (TEST_ERRNO == EACCES) {
128 printf("open failed with EACCES as expected\n");
129 exit(TPASS);
130 } else {
131 printf("open failed unexpectedly\n");
132 exit(TFAIL);
133 }
134 } else {
135 /* Wait for son completion */
136 if (waitpid(pid, &status, 0) == -1) {
137 perror("waitpid failed");
138 exit(TFAIL);
139 }
140 if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
141 exit(WEXITSTATUS(status));
142 }
143
144 /* Test 3: Fallback to initial uid and check we can again open
145 * the file with RDWR permissions.
146 */
147 tst_count++;
148 if (SETREUID(NULL, 0, 0) == -1) {
149 perror("setreuid failed");
150 exit(TFAIL);
151 }
152
153 TEST(tst_fd = open(testfile, O_RDWR));
154
155 if (TEST_RETURN == -1) {
156 perror("open failed unexpectedly");
157 exit(TFAIL);
158 } else {
159 printf("open call succeeded\n");
160 close(tst_fd);
161 }
162 }
163 exit(TPASS);
164 }
165
setup(void)166 static void setup(void)
167 {
168 tst_require_root();
169
170 ltpuser = getpwnam("nobody");
171 if (ltpuser == NULL)
172 tst_brkm(TBROK, NULL, "nobody must be a valid user.");
173
174 tst_tmpdir();
175
176 sprintf(testfile, "setreuid07file%d.tst", getpid());
177
178 /* Create test file */
179 fd = open(testfile, O_CREAT | O_RDWR, 0644);
180 if (fd < 0)
181 tst_brkm(TBROK | TERRNO,
182 cleanup, "cannot create test file");
183
184 tst_sig(FORK, DEF_HANDLER, cleanup);
185
186 TEST_PAUSE;
187 }
188
cleanup(void)189 static void cleanup(void)
190 {
191 close(fd);
192
193 tst_rmdir();
194 }
195