cap_test_capabilities.c revision 224910
1/*-
2 * Copyright (c) 2009-2011 Robert N. M. Watson
3 * Copyright (c) 2011 Jonathan Anderson
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28/*
29 * Test whether various operations on capabilities are properly masked for
30 * various object types.
31 */
32
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/tools/regression/security/cap_test/cap_test_capabilities.c 224910 2011-08-16 14:14:56Z jonathan $");
35
36#include <sys/param.h>
37#include <sys/capability.h>
38#include <sys/errno.h>
39#include <sys/mman.h>
40#include <sys/mount.h>
41#include <sys/stat.h>
42
43#include <err.h>
44#include <fcntl.h>
45#include <poll.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#include <unistd.h>
50
51#include "cap_test.h"
52
53#define	SYSCALL_FAIL(syscall, message) \
54	FAIL("%s:\t%s (rights 0x%jx)", #syscall, message, rights)
55
56/*
57 * Ensure that, if the capability had enough rights for the system call to
58 * pass, then it did. Otherwise, ensure that the errno is ENOTCAPABLE;
59 * capability restrictions should kick in before any other error logic.
60 */
61#define	CHECK_RESULT(syscall, rights_needed, succeeded)	do {		\
62	if ((rights & (rights_needed)) == (rights_needed)) {		\
63		if (!(succeeded))					\
64			SYSCALL_FAIL(syscall, "failed");		\
65	} else {							\
66		if (succeeded)						\
67			FAILX("%s:\tsucceeded when it shouldn't have"	\
68			    " (rights 0x%jx)", #syscall, rights);	\
69		else if (errno != ENOTCAPABLE)				\
70			SYSCALL_FAIL(syscall, "errno != ENOTCAPABLE");	\
71	}								\
72	errno = 0;							\
73} while (0)
74
75/*
76 * As above, but for the special mmap() case: unmap after successful mmap().
77 */
78#define	CHECK_MMAP_RESULT(rights_needed)	do {			\
79	if ((rights & (rights_needed)) == (rights_needed)) {		\
80		if (p == MAP_FAILED)					\
81			SYSCALL_FAIL(mmap, "failed");			\
82		else							\
83			(void)munmap(p, getpagesize());			\
84	} else {							\
85		if (p != MAP_FAILED) {					\
86			FAILX("%s:\tsucceeded when it shouldn't have"	\
87			    " (rights 0x%jx)", "mmap", rights);		\
88			(void)munmap(p, getpagesize());			\
89		} else if (errno != ENOTCAPABLE)			\
90			SYSCALL_FAIL(syscall, "errno != ENOTCAPABLE");	\
91	}								\
92	errno = 0;							\
93} while (0)
94
95/*
96 * Given a file descriptor, create a capability with specific rights and
97 * make sure only those rights work.
98*/
99static int
100try_file_ops(int fd, cap_rights_t rights)
101{
102	struct stat sb;
103	struct statfs sf;
104	int fd_cap, fd_capcap;
105	ssize_t ssize, ssize2;
106	off_t off;
107	void *p;
108	char ch;
109	int ret, is_nfs;
110	struct pollfd pollfd;
111	int success = PASSED;
112
113	REQUIRE(fstatfs(fd, &sf));
114	is_nfs = (strncmp("nfs", sf.f_fstypename, sizeof(sf.f_fstypename))
115	    == 0);
116
117	REQUIRE(fd_cap = cap_new(fd, rights));
118	REQUIRE(fd_capcap = cap_new(fd_cap, rights));
119	CHECK(fd_capcap != fd_cap);
120
121	pollfd.fd = fd_cap;
122	pollfd.events = POLLIN | POLLERR | POLLHUP;
123	pollfd.revents = 0;
124
125	ssize = read(fd_cap, &ch, sizeof(ch));
126	CHECK_RESULT(read, CAP_READ | CAP_SEEK, ssize >= 0);
127
128	ssize = pread(fd_cap, &ch, sizeof(ch), 0);
129	ssize2 = pread(fd_cap, &ch, sizeof(ch), 0);
130	CHECK_RESULT(pread, CAP_READ, ssize >= 0);
131	CHECK(ssize == ssize2);
132
133	ssize = write(fd_cap, &ch, sizeof(ch));
134	CHECK_RESULT(write, CAP_WRITE | CAP_SEEK, ssize >= 0);
135
136	ssize = pwrite(fd_cap, &ch, sizeof(ch), 0);
137	CHECK_RESULT(pwrite, CAP_WRITE, ssize >= 0);
138
139	off = lseek(fd_cap, 0, SEEK_SET);
140	CHECK_RESULT(lseek, CAP_SEEK, off >= 0);
141
142	/*
143	 * Note: this is not expected to work over NFS.
144	 */
145	ret = fchflags(fd_cap, UF_NODUMP);
146	CHECK_RESULT(fchflags, CAP_FCHFLAGS,
147	    (ret == 0) || (is_nfs && (errno == EOPNOTSUPP)));
148
149	ret = fstat(fd_cap, &sb);
150	CHECK_RESULT(fstat, CAP_FSTAT, ret == 0);
151
152	p = mmap(NULL, getpagesize(), PROT_READ, MAP_SHARED, fd_cap, 0);
153	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ);
154
155	p = mmap(NULL, getpagesize(), PROT_WRITE, MAP_SHARED, fd_cap, 0);
156	CHECK_MMAP_RESULT(CAP_MMAP | CAP_WRITE);
157
158	p = mmap(NULL, getpagesize(), PROT_EXEC, MAP_SHARED, fd_cap, 0);
159	CHECK_MMAP_RESULT(CAP_MMAP | CAP_MAPEXEC);
160
161	p = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_SHARED,
162	    fd_cap, 0);
163	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_WRITE);
164
165	p = mmap(NULL, getpagesize(), PROT_READ | PROT_EXEC, MAP_SHARED,
166	    fd_cap, 0);
167	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_MAPEXEC);
168
169	p = mmap(NULL, getpagesize(), PROT_EXEC | PROT_WRITE, MAP_SHARED,
170	    fd_cap, 0);
171	CHECK_MMAP_RESULT(CAP_MMAP | CAP_MAPEXEC | CAP_WRITE);
172
173	p = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE | PROT_EXEC,
174	    MAP_SHARED, fd_cap, 0);
175	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_WRITE | CAP_MAPEXEC);
176
177	ret = fsync(fd_cap);
178	CHECK_RESULT(fsync, CAP_FSYNC, ret == 0);
179
180	ret = fchown(fd_cap, -1, -1);
181	CHECK_RESULT(fchown, CAP_FCHOWN, ret == 0);
182
183	ret = fchmod(fd_cap, 0644);
184	CHECK_RESULT(fchmod, CAP_FCHMOD, ret == 0);
185
186	/* XXX flock */
187
188	ret = ftruncate(fd_cap, 0);
189	CHECK_RESULT(ftruncate, CAP_FTRUNCATE, ret == 0);
190
191	ret = fstatfs(fd_cap, &sf);
192	CHECK_RESULT(fstatfs, CAP_FSTATFS, ret == 0);
193
194	ret = fpathconf(fd_cap, _PC_NAME_MAX);
195	CHECK_RESULT(fpathconf, CAP_FPATHCONF, ret >= 0);
196
197	ret = futimes(fd_cap, NULL);
198	CHECK_RESULT(futimes, CAP_FUTIMES, ret == 0);
199
200	ret = poll(&pollfd, 1, 0);
201	if (rights & CAP_POLL_EVENT)
202		CHECK((pollfd.revents & POLLNVAL) == 0);
203	else
204		CHECK((pollfd.revents & POLLNVAL) != 0);
205
206	/* XXX: select, kqueue */
207
208	close (fd_cap);
209	return (success);
210}
211
212#define TRY(fd, rights) \
213do { \
214	if (success == PASSED) \
215		success = try_file_ops(fd, rights); \
216	else \
217		/* We've already failed, but try the test anyway. */ \
218		try_file_ops(fd, rights); \
219} while (0)
220
221int
222test_capabilities(void)
223{
224	int fd;
225	int success = PASSED;
226
227	fd = open("/tmp/cap_test_capabilities", O_RDWR | O_CREAT, 0644);
228	if (fd < 0)
229		err(-1, "open");
230
231	if (cap_enter() < 0)
232		err(-1, "cap_enter");
233
234	/* XXX: Really want to try all combinations. */
235	TRY(fd, CAP_READ);
236	TRY(fd, CAP_READ | CAP_SEEK);
237	TRY(fd, CAP_WRITE);
238	TRY(fd, CAP_WRITE | CAP_SEEK);
239	TRY(fd, CAP_READ | CAP_WRITE);
240	TRY(fd, CAP_READ | CAP_WRITE | CAP_SEEK);
241	TRY(fd, CAP_SEEK);
242	TRY(fd, CAP_FCHFLAGS);
243	TRY(fd, CAP_IOCTL);
244	TRY(fd, CAP_FSTAT);
245	TRY(fd, CAP_MMAP);
246	TRY(fd, CAP_MMAP | CAP_READ);
247	TRY(fd, CAP_MMAP | CAP_WRITE);
248	TRY(fd, CAP_MMAP | CAP_MAPEXEC);
249	TRY(fd, CAP_MMAP | CAP_READ | CAP_WRITE);
250	TRY(fd, CAP_MMAP | CAP_READ | CAP_MAPEXEC);
251	TRY(fd, CAP_MMAP | CAP_MAPEXEC | CAP_WRITE);
252	TRY(fd, CAP_MMAP | CAP_READ | CAP_WRITE | CAP_MAPEXEC);
253	TRY(fd, CAP_FCNTL);
254	TRY(fd, CAP_POST_EVENT);
255	TRY(fd, CAP_POLL_EVENT);
256	TRY(fd, CAP_FSYNC);
257	TRY(fd, CAP_FCHOWN);
258	TRY(fd, CAP_FCHMOD);
259	TRY(fd, CAP_FTRUNCATE);
260	TRY(fd, CAP_FLOCK);
261	TRY(fd, CAP_FSTATFS);
262	TRY(fd, CAP_FPATHCONF);
263	TRY(fd, CAP_FUTIMES);
264	TRY(fd, CAP_ACL_GET);
265	TRY(fd, CAP_ACL_SET);
266	TRY(fd, CAP_ACL_DELETE);
267	TRY(fd, CAP_ACL_CHECK);
268	TRY(fd, CAP_EXTATTR_GET);
269	TRY(fd, CAP_EXTATTR_SET);
270	TRY(fd, CAP_EXTATTR_DELETE);
271	TRY(fd, CAP_EXTATTR_LIST);
272	TRY(fd, CAP_MAC_GET);
273	TRY(fd, CAP_MAC_SET);
274
275	/*
276	 * Socket-specific.
277	 */
278	TRY(fd, CAP_GETPEERNAME);
279	TRY(fd, CAP_GETSOCKNAME);
280	TRY(fd, CAP_ACCEPT);
281
282	return (success);
283}
284