1/* $NetBSD: t_chroot.c,v 1.2 2017/01/10 22:36:29 christos Exp $ */
2
3/*-
4 * Copyright (c) 2011 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jukka Ruohonen.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31#include <sys/cdefs.h>
32__RCSID("$NetBSD: t_chroot.c,v 1.2 2017/01/10 22:36:29 christos Exp $");
33
34#include <sys/wait.h>
35#include <sys/stat.h>
36
37#include <atf-c.h>
38#include <errno.h>
39#include <fcntl.h>
40#include <limits.h>
41#include <pwd.h>
42#include <stdlib.h>
43#include <string.h>
44#include <unistd.h>
45
46ATF_TC(chroot_basic);
47ATF_TC_HEAD(chroot_basic, tc)
48{
49	atf_tc_set_md_var(tc, "descr", "A basic test of chroot(2)");
50	atf_tc_set_md_var(tc, "require.user", "root");
51}
52
53ATF_TC_BODY(chroot_basic, tc)
54{
55	char buf[PATH_MAX];
56	int fd, sta;
57	pid_t pid;
58
59	(void)memset(buf, '\0', sizeof(buf));
60	(void)getcwd(buf, sizeof(buf));
61	(void)strlcat(buf, "/dir", sizeof(buf));
62
63	ATF_REQUIRE(mkdir(buf, 0500) == 0);
64	ATF_REQUIRE(chdir(buf) == 0);
65
66	pid = fork();
67	ATF_REQUIRE(pid >= 0);
68
69	if (pid == 0) {
70
71		if (chroot(buf) != 0)
72			_exit(EXIT_FAILURE);
73
74		errno = 0;
75
76		if (chroot("/root") != -1)
77			_exit(EXIT_FAILURE);
78
79		if (errno != ENOENT)
80			_exit(EXIT_FAILURE);
81
82		fd = open("file", O_RDONLY | O_CREAT, 0600);
83
84		if (fd < 0)
85			_exit(EXIT_FAILURE);
86
87		if (close(fd) != 0)
88			_exit(EXIT_FAILURE);
89
90		_exit(EXIT_SUCCESS);
91	}
92
93	(void)wait(&sta);
94
95	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
96		atf_tc_fail("chroot(2) failed");
97
98	(void)chdir("/");
99	(void)strlcat(buf, "/file", sizeof(buf));
100
101	fd = open(buf, O_RDONLY);
102
103	if (fd < 0)
104		atf_tc_fail("chroot(2) did not change the root directory");
105
106	ATF_REQUIRE(close(fd) == 0);
107	ATF_REQUIRE(unlink(buf) == 0);
108}
109
110ATF_TC(chroot_err);
111ATF_TC_HEAD(chroot_err, tc)
112{
113	atf_tc_set_md_var(tc, "descr", "Test error conditions of chroot(2)");
114	atf_tc_set_md_var(tc, "require.user", "root");
115}
116
117ATF_TC_BODY(chroot_err, tc)
118{
119	char buf[PATH_MAX + 1];
120
121	(void)memset(buf, 'x', sizeof(buf));
122
123	errno = 0;
124	ATF_REQUIRE_ERRNO(ENAMETOOLONG, chroot(buf) == -1);
125
126	errno = 0;
127	ATF_REQUIRE_ERRNO(EFAULT, chroot((void *)-1) == -1);
128
129	errno = 0;
130	ATF_REQUIRE_ERRNO(ENOENT, chroot("/a/b/c/d/e/f/g/h/i/j") == -1);
131}
132
133ATF_TC(chroot_perm);
134ATF_TC_HEAD(chroot_perm, tc)
135{
136	atf_tc_set_md_var(tc, "descr", "Test permissions with chroot(2)");
137	atf_tc_set_md_var(tc, "require.user", "unprivileged");
138}
139
140ATF_TC_BODY(chroot_perm, tc)
141{
142	static char buf[LINE_MAX];
143	pid_t pid;
144	int sta;
145
146	(void)memset(buf, '\0', sizeof(buf));
147	ATF_REQUIRE(getcwd(buf, sizeof(buf)) != NULL);
148
149	pid = fork();
150	ATF_REQUIRE(pid >= 0);
151
152	if (pid == 0) {
153
154		errno = 0;
155
156		if (chroot(buf) != -1)
157			_exit(EXIT_FAILURE);
158
159		if (errno != EPERM)
160			_exit(EXIT_FAILURE);
161
162		_exit(EXIT_SUCCESS);
163	}
164
165	(void)wait(&sta);
166
167	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
168		atf_tc_fail("chroot(2) succeeded as unprivileged user");
169}
170
171ATF_TC(fchroot_basic);
172ATF_TC_HEAD(fchroot_basic, tc)
173{
174	atf_tc_set_md_var(tc, "descr", "A basic test of fchroot(2)");
175	atf_tc_set_md_var(tc, "require.user", "root");
176}
177
178ATF_TC_BODY(fchroot_basic, tc)
179{
180	char buf[PATH_MAX];
181	int fd, sta;
182	pid_t pid;
183
184	(void)memset(buf, '\0', sizeof(buf));
185	(void)getcwd(buf, sizeof(buf));
186	(void)strlcat(buf, "/dir", sizeof(buf));
187
188	ATF_REQUIRE(mkdir(buf, 0500) == 0);
189	ATF_REQUIRE(chdir(buf) == 0);
190
191	fd = open(buf, O_RDONLY);
192	ATF_REQUIRE(fd >= 0);
193
194	pid = fork();
195	ATF_REQUIRE(pid >= 0);
196
197	if (pid == 0) {
198
199		if (fchroot(fd) != 0)
200			_exit(EXIT_FAILURE);
201
202		if (close(fd) != 0)
203			_exit(EXIT_FAILURE);
204
205		fd = open("file", O_RDONLY | O_CREAT, 0600);
206
207		if (fd < 0)
208			_exit(EXIT_FAILURE);
209
210		if (close(fd) != 0)
211			_exit(EXIT_FAILURE);
212
213		_exit(EXIT_SUCCESS);
214	}
215
216	(void)wait(&sta);
217
218	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
219		atf_tc_fail("fchroot(2) failed");
220
221	(void)chdir("/");
222	(void)strlcat(buf, "/file", sizeof(buf));
223
224	fd = open(buf, O_RDONLY);
225
226	if (fd < 0)
227		atf_tc_fail("fchroot(2) did not change the root directory");
228
229	ATF_REQUIRE(close(fd) == 0);
230	ATF_REQUIRE(unlink(buf) == 0);
231}
232
233ATF_TC(fchroot_err);
234ATF_TC_HEAD(fchroot_err, tc)
235{
236	atf_tc_set_md_var(tc, "descr", "Test error conditions of fchroot(2)");
237	atf_tc_set_md_var(tc, "require.user", "root");
238}
239
240ATF_TC_BODY(fchroot_err, tc)
241{
242	int fd;
243
244	fd = open("/etc/passwd", O_RDONLY);
245	ATF_REQUIRE(fd >= 0);
246
247	errno = 0;
248	ATF_REQUIRE_ERRNO(EBADF, fchroot(-1) == -1);
249
250	errno = 0;
251	ATF_REQUIRE_ERRNO(ENOTDIR, fchroot(fd) == -1);
252
253	ATF_REQUIRE(close(fd) == 0);
254}
255
256ATF_TC(fchroot_perm);
257ATF_TC_HEAD(fchroot_perm, tc)
258{
259	atf_tc_set_md_var(tc, "descr", "Test permissions with fchroot(2)");
260	atf_tc_set_md_var(tc, "require.user", "root");
261}
262
263ATF_TC_BODY(fchroot_perm, tc)
264{
265	static char buf[LINE_MAX];
266	struct passwd *pw;
267	int fd, sta;
268	pid_t pid;
269
270	(void)memset(buf, '\0', sizeof(buf));
271	ATF_REQUIRE(getcwd(buf, sizeof(buf)) != NULL);
272
273	pw = getpwnam("nobody");
274	fd = open(buf, O_RDONLY);
275
276	ATF_REQUIRE(fd >= 0);
277	ATF_REQUIRE(pw != NULL);
278
279	pid = fork();
280	ATF_REQUIRE(pid >= 0);
281
282	if (pid == 0) {
283
284		(void)setuid(pw->pw_uid);
285
286		errno = 0;
287
288		if (fchroot(fd) != -1)
289			_exit(EXIT_FAILURE);
290
291		if (errno != EPERM)
292			_exit(EXIT_FAILURE);
293
294		_exit(EXIT_SUCCESS);
295	}
296
297	(void)wait(&sta);
298
299	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
300		atf_tc_fail("fchroot(2) succeeded as unprivileged user");
301}
302
303ATF_TP_ADD_TCS(tp)
304{
305
306	ATF_TP_ADD_TC(tp, chroot_basic);
307	ATF_TP_ADD_TC(tp, chroot_err);
308	ATF_TP_ADD_TC(tp, chroot_perm);
309	ATF_TP_ADD_TC(tp, fchroot_basic);
310	ATF_TP_ADD_TC(tp, fchroot_err);
311	ATF_TP_ADD_TC(tp, fchroot_perm);
312
313	return atf_no_error();
314}
315