1/*-
2 * Copyright (c) 2016 Ed Maste <emaste@FreeBSD.org>
3 * Copyright (c) 2016 Conrad Meyer <cem@FreeBSD.org>
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/param.h>
28#include <sys/capsicum.h>
29#include <sys/sysctl.h>
30#include <sys/stat.h>
31
32#include <atf-c.h>
33#include <errno.h>
34#include <stdlib.h>
35#include <string.h>
36
37#include "freebsd_test_suite/macros.h"
38
39static int dirfd = -1;
40static char *abspath;
41
42static void
43touchat(int _dirfd, const char *name)
44{
45	int fd;
46
47	ATF_REQUIRE((fd = openat(_dirfd, name, O_CREAT | O_TRUNC | O_WRONLY,
48	    0777)) >= 0);
49	ATF_REQUIRE(close(fd) == 0);
50}
51
52static void
53prepare_dotdot_tests(void)
54{
55	char cwd[MAXPATHLEN];
56
57	ATF_REQUIRE(getcwd(cwd, sizeof(cwd)) != NULL);
58	asprintf(&abspath, "%s/testdir/d1/f1", cwd);
59
60	ATF_REQUIRE(mkdir("testdir", 0777) == 0);
61	ATF_REQUIRE((dirfd = open("testdir", O_RDONLY)) >= 0);
62
63	ATF_REQUIRE(mkdirat(dirfd, "d1", 0777) == 0);
64	ATF_REQUIRE(mkdirat(dirfd, "d1/d2", 0777) == 0);
65	ATF_REQUIRE(mkdirat(dirfd, "d1/d2/d3", 0777) == 0);
66	touchat(dirfd, "d1/f1");
67	touchat(dirfd, "d1/d2/f2");
68	touchat(dirfd, "d1/d2/d3/f3");
69	ATF_REQUIRE(symlinkat("d1/d2/d3", dirfd, "l3") == 0);
70	ATF_REQUIRE(symlinkat("../testdir/d1", dirfd, "lup") == 0);
71	ATF_REQUIRE(symlinkat("../..", dirfd, "d1/d2/d3/ld1") == 0);
72	ATF_REQUIRE(symlinkat("../../f1", dirfd, "d1/d2/d3/lf1") == 0);
73}
74
75static void
76check_capsicum(void)
77{
78	ATF_REQUIRE_FEATURE("security_capabilities");
79	ATF_REQUIRE_FEATURE("security_capability_mode");
80	ATF_REQUIRE_SYSCTL_BOOL("kern.trap_enotcap", false);
81}
82
83/*
84 * Positive tests
85 */
86ATF_TC(openat__basic_positive);
87ATF_TC_HEAD(openat__basic_positive, tc)
88{
89	atf_tc_set_md_var(tc, "descr", "Basic positive openat testcases");
90}
91
92ATF_TC_BODY(openat__basic_positive, tc)
93{
94	prepare_dotdot_tests();
95
96	ATF_REQUIRE(openat(dirfd, "d1/d2/d3/f3", O_RDONLY) >= 0);
97	ATF_REQUIRE(openat(dirfd, "d1/d2/d3/../../f1", O_RDONLY) >= 0);
98	ATF_REQUIRE(openat(dirfd, "l3/f3", O_RDONLY) >= 0);
99	ATF_REQUIRE(openat(dirfd, "l3/../../f1", O_RDONLY) >= 0);
100	ATF_REQUIRE(openat(dirfd, "../testdir/d1/f1", O_RDONLY) >= 0);
101	ATF_REQUIRE(openat(dirfd, "lup/f1", O_RDONLY) >= 0);
102	ATF_REQUIRE(openat(dirfd, "l3/ld1", O_RDONLY) >= 0);
103	ATF_REQUIRE(openat(dirfd, "l3/lf1", O_RDONLY) >= 0);
104	ATF_REQUIRE(open(abspath, O_RDONLY) >= 0);
105	ATF_REQUIRE(openat(dirfd, abspath, O_RDONLY) >= 0);
106}
107
108ATF_TC(lookup_cap_dotdot__basic);
109ATF_TC_HEAD(lookup_cap_dotdot__basic, tc)
110{
111	atf_tc_set_md_var(tc, "descr",
112	    "Validate cap-mode (testdir)/d1/.. lookup");
113}
114
115ATF_TC_BODY(lookup_cap_dotdot__basic, tc)
116{
117	cap_rights_t rights;
118
119	check_capsicum();
120	prepare_dotdot_tests();
121
122	cap_rights_init(&rights, CAP_LOOKUP, CAP_READ);
123	ATF_REQUIRE(cap_rights_limit(dirfd, &rights) >= 0);
124
125	ATF_REQUIRE(cap_enter() >= 0);
126
127	ATF_REQUIRE_MSG(openat(dirfd, "d1/..", O_RDONLY) >= 0, "%s",
128	    strerror(errno));
129}
130
131ATF_TC(lookup_cap_dotdot__advanced);
132ATF_TC_HEAD(lookup_cap_dotdot__advanced, tc)
133{
134	atf_tc_set_md_var(tc, "descr",
135	    "Validate cap-mode (testdir)/d1/.. lookup");
136}
137
138ATF_TC_BODY(lookup_cap_dotdot__advanced, tc)
139{
140	cap_rights_t rights;
141
142	check_capsicum();
143	prepare_dotdot_tests();
144
145	cap_rights_init(&rights, CAP_LOOKUP, CAP_READ);
146	ATF_REQUIRE(cap_rights_limit(dirfd, &rights) >= 0);
147
148	ATF_REQUIRE(cap_enter() >= 0);
149
150	ATF_REQUIRE(openat(dirfd, "d1/d2/d3/../../f1", O_RDONLY) >= 0);
151	ATF_REQUIRE(openat(dirfd, "l3/../../f1", O_RDONLY) >= 0);
152	ATF_REQUIRE(openat(dirfd, "l3/ld1", O_RDONLY) >= 0);
153	ATF_REQUIRE(openat(dirfd, "l3/lf1", O_RDONLY) >= 0);
154}
155
156/*
157 * Negative tests
158 */
159ATF_TC(openat__basic_negative);
160ATF_TC_HEAD(openat__basic_negative, tc)
161{
162	atf_tc_set_md_var(tc, "descr", "Basic negative openat testcases");
163}
164
165ATF_TC_BODY(openat__basic_negative, tc)
166{
167	prepare_dotdot_tests();
168
169	ATF_REQUIRE_ERRNO(ENOENT,
170	    openat(dirfd, "does-not-exist", O_RDONLY) < 0);
171	ATF_REQUIRE_ERRNO(ENOENT,
172	    openat(dirfd, "l3/does-not-exist", O_RDONLY) < 0);
173}
174
175ATF_TC(capmode__negative);
176ATF_TC_HEAD(capmode__negative, tc)
177{
178	atf_tc_set_md_var(tc, "descr", "Negative Capability mode testcases");
179}
180
181ATF_TC_BODY(capmode__negative, tc)
182{
183	int subdirfd;
184
185	check_capsicum();
186	prepare_dotdot_tests();
187
188	ATF_REQUIRE(cap_enter() == 0);
189
190	/* open() not permitted in capability mode */
191	ATF_REQUIRE_ERRNO(ECAPMODE, open("testdir", O_RDONLY) < 0);
192
193	/* AT_FDCWD not permitted in capability mode */
194	ATF_REQUIRE_ERRNO(ECAPMODE, openat(AT_FDCWD, "d1/f1", O_RDONLY) < 0);
195
196	/* Relative path above dirfd not capable */
197	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, "..", O_RDONLY) < 0);
198	ATF_REQUIRE((subdirfd = openat(dirfd, "l3", O_RDONLY)) >= 0);
199	ATF_REQUIRE_ERRNO(ENOTCAPABLE,
200	    openat(subdirfd, "../../f1", O_RDONLY) < 0);
201
202	/* Absolute paths not capable */
203	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, abspath, O_RDONLY) < 0);
204
205	/* Symlink above dirfd */
206	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, "lup/f1", O_RDONLY) < 0);
207}
208
209ATF_TC(lookup_cap_dotdot__negative);
210ATF_TC_HEAD(lookup_cap_dotdot__negative, tc)
211{
212	atf_tc_set_md_var(tc, "descr",
213	    "Validate cap-mode (testdir)/.. lookup fails");
214}
215
216ATF_TC_BODY(lookup_cap_dotdot__negative, tc)
217{
218	cap_rights_t rights;
219
220	check_capsicum();
221	prepare_dotdot_tests();
222
223	cap_rights_init(&rights, CAP_LOOKUP, CAP_READ);
224	ATF_REQUIRE(cap_rights_limit(dirfd, &rights) >= 0);
225
226	ATF_REQUIRE(cap_enter() >= 0);
227
228	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, "..", O_RDONLY) < 0);
229	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, "d1/../..", O_RDONLY) < 0);
230	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dirfd, "../testdir/d1/f1", O_RDONLY) < 0);
231}
232
233ATF_TC(lookup_cap_dotdot__root);
234ATF_TC_HEAD(lookup_cap_dotdot__root, tc)
235{
236	atf_tc_set_md_var(tc, "descr", "Validate cap-mode /.. lookup fails");
237}
238
239ATF_TC_BODY(lookup_cap_dotdot__root, tc)
240{
241	int dfd, dfd2;
242
243	check_capsicum();
244
245	dfd = open("/", O_DIRECTORY);
246	ATF_REQUIRE(dfd >= 0);
247
248	dfd2 = openat(dfd, "..", O_DIRECTORY);
249	ATF_REQUIRE(dfd2 >= 0);
250	ATF_REQUIRE(close(dfd2) == 0);
251
252	ATF_REQUIRE(cap_enter() >= 0);
253
254	dfd2 = openat(dfd, "..", O_DIRECTORY);
255	ATF_REQUIRE_ERRNO(ENOTCAPABLE, openat(dfd, "..", O_DIRECTORY));
256}
257
258ATF_TP_ADD_TCS(tp)
259{
260
261	ATF_TP_ADD_TC(tp, openat__basic_positive);
262	ATF_TP_ADD_TC(tp, openat__basic_negative);
263
264	ATF_TP_ADD_TC(tp, capmode__negative);
265
266	ATF_TP_ADD_TC(tp, lookup_cap_dotdot__basic);
267	ATF_TP_ADD_TC(tp, lookup_cap_dotdot__advanced);
268	ATF_TP_ADD_TC(tp, lookup_cap_dotdot__negative);
269	ATF_TP_ADD_TC(tp, lookup_cap_dotdot__root);
270
271	return (atf_no_error());
272}
273