cap_test_capabilities.c revision 224660
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 224660 2011-08-05 17:43:11Z 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 <stdio.h>
46#include <stdlib.h>
47#include <string.h>
48#include <unistd.h>
49
50#include "cap_test.h"
51
52#define	SYSCALL_FAIL(syscall, message) \
53	FAIL("%s:\t%s (rights 0x%jx)", #syscall, message, rights)
54
55/*
56 * Ensure that, if the capability had enough rights for the system call to
57 * pass, then it did. Otherwise, ensure that the errno is ENOTCAPABLE;
58 * capability restrictions should kick in before any other error logic.
59 */
60#define	CHECK_RESULT(syscall, rights_needed, succeeded)	do {		\
61	if ((rights & (rights_needed)) == (rights_needed)) {		\
62		if (!(succeeded))					\
63			SYSCALL_FAIL(syscall, "failed");		\
64	} else {							\
65		if (succeeded)						\
66			FAILX("%s:\tsucceeded when it shouldn't have"	\
67			    " (rights 0x%jx)", #syscall, rights);	\
68		else if (errno != ENOTCAPABLE)				\
69			SYSCALL_FAIL(syscall, "errno != ENOTCAPABLE");	\
70	}								\
71} while (0)
72
73/*
74 * As above, but for the special mmap() case: unmap after successful mmap().
75 */
76#define	CHECK_MMAP_RESULT(rights_needed)	do {			\
77	if ((rights & (rights_needed)) == (rights_needed)) {		\
78		if (p == MAP_FAILED)					\
79			SYSCALL_FAIL(mmap, "failed");			\
80		else							\
81			(void)munmap(p, getpagesize());			\
82	} else {							\
83		if (p != MAP_FAILED) {					\
84			FAILX("%s:\tsucceeded when it shouldn't have"	\
85			    " (rights 0x%jx)", "mmap", rights);		\
86			(void)munmap(p, getpagesize());			\
87		} else if (errno != ENOTCAPABLE)			\
88			SYSCALL_FAIL(syscall, "errno != ENOTCAPABLE");	\
89	}								\
90} while (0)
91
92/*
93 * Given a file descriptor, create a capability with specific rights and
94 * make sure only those rights work.
95*/
96static int
97try_file_ops(int fd, cap_rights_t rights)
98{
99	struct stat sb;
100	struct statfs sf;
101	int fd_cap, fd_capcap;
102	ssize_t ssize, ssize2;
103	off_t off;
104	void *p;
105	char ch;
106	int ret, is_nfs;
107	int success = PASSED;
108
109	REQUIRE(fstatfs(fd, &sf));
110	is_nfs = (strncmp("nfs", sf.f_fstypename, sizeof(sf.f_fstypename))
111	    == 0);
112
113	REQUIRE(fd_cap = cap_new(fd, rights));
114	REQUIRE(fd_capcap = cap_new(fd_cap, rights));
115	CHECK(fd_capcap != fd_cap);
116
117	ssize = read(fd_cap, &ch, sizeof(ch));
118	CHECK_RESULT(read, CAP_READ | CAP_SEEK, ssize >= 0);
119
120	ssize = pread(fd_cap, &ch, sizeof(ch), 0);
121	ssize2 = pread(fd_cap, &ch, sizeof(ch), 0);
122	CHECK_RESULT(pread, CAP_READ, ssize >= 0);
123	CHECK(ssize == ssize2);
124
125	ssize = write(fd_cap, &ch, sizeof(ch));
126	CHECK_RESULT(write, CAP_WRITE | CAP_SEEK, ssize >= 0);
127
128	ssize = pwrite(fd_cap, &ch, sizeof(ch), 0);
129	CHECK_RESULT(pwrite, CAP_WRITE, ssize >= 0);
130
131	off = lseek(fd_cap, 0, SEEK_SET);
132	CHECK_RESULT(lseek, CAP_SEEK, off >= 0);
133
134	/*
135	 * Note: this is not expected to work over NFS.
136	 */
137	ret = fchflags(fd_cap, UF_NODUMP);
138	CHECK_RESULT(fchflags, CAP_FCHFLAGS,
139	    (ret == 0) || (is_nfs && (errno == EOPNOTSUPP)));
140
141	ret = fstat(fd_cap, &sb);
142	CHECK_RESULT(fstat, CAP_FSTAT, ret == 0);
143
144	p = mmap(NULL, getpagesize(), PROT_READ, MAP_SHARED, fd_cap, 0);
145	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ);
146
147	p = mmap(NULL, getpagesize(), PROT_WRITE, MAP_SHARED, fd_cap, 0);
148	CHECK_MMAP_RESULT(CAP_MMAP | CAP_WRITE);
149
150	p = mmap(NULL, getpagesize(), PROT_EXEC, MAP_SHARED, fd_cap, 0);
151	CHECK_MMAP_RESULT(CAP_MMAP | CAP_MAPEXEC);
152
153	p = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_SHARED,
154	    fd_cap, 0);
155	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_WRITE);
156
157	p = mmap(NULL, getpagesize(), PROT_READ | PROT_EXEC, MAP_SHARED,
158	    fd_cap, 0);
159	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_MAPEXEC);
160
161	p = mmap(NULL, getpagesize(), PROT_EXEC | PROT_WRITE, MAP_SHARED,
162	    fd_cap, 0);
163	CHECK_MMAP_RESULT(CAP_MMAP | CAP_MAPEXEC | CAP_WRITE);
164
165	p = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE | PROT_EXEC,
166	    MAP_SHARED, fd_cap, 0);
167	CHECK_MMAP_RESULT(CAP_MMAP | CAP_READ | CAP_WRITE | CAP_MAPEXEC);
168
169	ret = fsync(fd_cap);
170	CHECK_RESULT(fsync, CAP_FSYNC, ret == 0);
171
172	ret = fchown(fd_cap, -1, -1);
173	CHECK_RESULT(fchown, CAP_FCHOWN, ret == 0);
174
175	ret = fchmod(fd_cap, 0644);
176	CHECK_RESULT(fchmod, CAP_FCHMOD, ret == 0);
177
178	/* XXX flock */
179
180	ret = ftruncate(fd_cap, 0);
181	CHECK_RESULT(ftruncate, CAP_FTRUNCATE, ret == 0);
182
183	ret = fstatfs(fd_cap, &sf);
184	CHECK_RESULT(fstatfs, CAP_FSTATFS, ret == 0);
185
186	ret = fpathconf(fd_cap, _PC_NAME_MAX);
187	CHECK_RESULT(fpathconf, CAP_FPATHCONF, ret >= 0);
188
189	ret = futimes(fd_cap, NULL);
190	CHECK_RESULT(futimes, CAP_FUTIMES, ret == 0);
191
192	/* XXX select / poll / kqueue */
193
194	close (fd_cap);
195	return (success);
196}
197
198#define TRY(fd, rights) \
199do { \
200	if (success == PASSED) \
201		success = try_file_ops(fd, rights); \
202	else \
203		/* We've already failed, but try the test anyway. */ \
204		try_file_ops(fd, rights); \
205} while (0)
206
207int
208test_capabilities(void)
209{
210	int fd;
211	int success = PASSED;
212
213	fd = open("/tmp/cap_test", O_RDWR | O_CREAT, 0644);
214	if (fd < 0)
215		err(-1, "open");
216
217	if (cap_enter() < 0)
218		err(-1, "cap_enter");
219
220	/* XXX: Really want to try all combinations. */
221	TRY(fd, CAP_READ);
222	TRY(fd, CAP_READ | CAP_SEEK);
223	TRY(fd, CAP_WRITE);
224	TRY(fd, CAP_WRITE | CAP_SEEK);
225	TRY(fd, CAP_READ | CAP_WRITE);
226	TRY(fd, CAP_READ | CAP_WRITE | CAP_SEEK);
227	TRY(fd, CAP_SEEK);
228	TRY(fd, CAP_FCHFLAGS);
229	TRY(fd, CAP_IOCTL);
230	TRY(fd, CAP_FSTAT);
231	TRY(fd, CAP_MMAP);
232	TRY(fd, CAP_MMAP | CAP_READ);
233	TRY(fd, CAP_MMAP | CAP_WRITE);
234	TRY(fd, CAP_MMAP | CAP_MAPEXEC);
235	TRY(fd, CAP_MMAP | CAP_READ | CAP_WRITE);
236	TRY(fd, CAP_MMAP | CAP_READ | CAP_MAPEXEC);
237	TRY(fd, CAP_MMAP | CAP_MAPEXEC | CAP_WRITE);
238	TRY(fd, CAP_MMAP | CAP_READ | CAP_WRITE | CAP_MAPEXEC);
239	TRY(fd, CAP_FCNTL);
240	TRY(fd, CAP_EVENT);
241	TRY(fd, CAP_KEVENT);
242	TRY(fd, CAP_FSYNC);
243	TRY(fd, CAP_FCHOWN);
244	TRY(fd, CAP_FCHMOD);
245	TRY(fd, CAP_FTRUNCATE);
246	TRY(fd, CAP_FLOCK);
247	TRY(fd, CAP_FSTATFS);
248	TRY(fd, CAP_FPATHCONF);
249	TRY(fd, CAP_FUTIMES);
250	TRY(fd, CAP_ACL_GET);
251	TRY(fd, CAP_ACL_SET);
252	TRY(fd, CAP_ACL_DELETE);
253	TRY(fd, CAP_ACL_CHECK);
254	TRY(fd, CAP_EXTATTR_GET);
255	TRY(fd, CAP_EXTATTR_SET);
256	TRY(fd, CAP_EXTATTR_DELETE);
257	TRY(fd, CAP_EXTATTR_LIST);
258	TRY(fd, CAP_MAC_GET);
259	TRY(fd, CAP_MAC_SET);
260
261	/*
262	 * Socket-specific.
263	 */
264	TRY(fd, CAP_GETPEERNAME);
265	TRY(fd, CAP_GETSOCKNAME);
266	TRY(fd, CAP_ACCEPT);
267
268	return (success);
269}
270