1/*-
2 * Copyright (c) 2008-2009 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 routines to make sure a variety of system calls are or are not
30 * available in capability mode.  The goal is not to see if they work, just
31 * whether or not they return the expected ECAPMODE.
32 */
33
34#include <sys/param.h>
35#include <sys/capsicum.h>
36#include <sys/errno.h>
37#include <sys/mman.h>
38#include <sys/mount.h>
39#include <sys/socket.h>
40#include <sys/stat.h>
41#include <sys/wait.h>
42
43#include <machine/sysarch.h>
44
45#include <err.h>
46#include <fcntl.h>
47#include <stdlib.h>
48#include <string.h>
49#include <unistd.h>
50
51#include "cap_test.h"
52
53#define	CHECK_SYSCALL_VOID_NOT_ECAPMODE(syscall, ...)	do {		\
54	errno = 0;							\
55	(void)syscall(__VA_ARGS__);					\
56	if (errno == ECAPMODE)						\
57		FAIL("capmode: %s failed with ECAPMODE", #syscall);	\
58} while (0)
59
60int
61test_capmode(void)
62{
63	struct statfs statfs;
64	struct stat sb;
65	long sysarch_arg = 0;
66	int fd_close, fd_dir, fd_file, fd_socket, fd2[2];
67	int success = PASSED;
68	pid_t pid, wpid;
69	char ch;
70
71	/* Open some files to play with. */
72	REQUIRE(fd_file = open("/tmp/cap_capmode", O_RDWR|O_CREAT, 0644));
73	REQUIRE(fd_close = open("/dev/null", O_RDWR));
74	REQUIRE(fd_dir = open("/tmp", O_RDONLY));
75	REQUIRE(fd_socket = socket(PF_INET, SOCK_DGRAM, 0));
76
77	/* Enter capability mode. */
78	REQUIRE(cap_enter());
79
80	/*
81	 * System calls that are not permitted in capability mode.
82	 */
83	CHECK_CAPMODE(access, "/tmp/cap_capmode_access", F_OK);
84	CHECK_CAPMODE(acct, "/tmp/cap_capmode_acct");
85	CHECK_CAPMODE(bind, PF_INET, NULL, 0);
86	CHECK_CAPMODE(chdir, "/tmp/cap_capmode_chdir");
87	CHECK_CAPMODE(chflags, "/tmp/cap_capmode_chflags", UF_NODUMP);
88	CHECK_CAPMODE(chmod, "/tmp/cap_capmode_chmod", 0644);
89	CHECK_CAPMODE(chown, "/tmp/cap_capmode_chown", -1, -1);
90	CHECK_CAPMODE(chroot, "/tmp/cap_capmode_chroot");
91	CHECK_CAPMODE(connect, PF_INET, NULL, 0);
92	CHECK_CAPMODE(creat, "/tmp/cap_capmode_creat", 0644);
93	CHECK_CAPMODE(fchdir, fd_dir);
94	CHECK_CAPMODE(getfsstat, &statfs, sizeof(statfs), MNT_NOWAIT);
95	CHECK_CAPMODE(link, "/tmp/foo", "/tmp/bar");
96	CHECK_CAPMODE(lstat, "/tmp/cap_capmode_lstat", &sb);
97	CHECK_CAPMODE(mknod, "/tmp/capmode_mknod", 06440, 0);
98	CHECK_CAPMODE(mount, "procfs", "/not_mounted", 0, NULL);
99	CHECK_CAPMODE(open, "/dev/null", O_RDWR);
100	CHECK_CAPMODE(readlink, "/tmp/cap_capmode_readlink", NULL, 0);
101	CHECK_CAPMODE(revoke, "/tmp/cap_capmode_revoke");
102	CHECK_CAPMODE(stat, "/tmp/cap_capmode_stat", &sb);
103	CHECK_CAPMODE(symlink,
104	    "/tmp/cap_capmode_symlink_from",
105	    "/tmp/cap_capmode_symlink_to");
106	CHECK_CAPMODE(unlink, "/tmp/cap_capmode_unlink");
107	CHECK_CAPMODE(unmount, "/not_mounted", 0);
108
109	/*
110	 * System calls that are permitted in capability mode.
111	 */
112	CHECK_SYSCALL_SUCCEEDS(close, fd_close);
113	CHECK_SYSCALL_SUCCEEDS(dup, fd_file);
114	CHECK_SYSCALL_SUCCEEDS(fstat, fd_file, &sb);
115	CHECK_SYSCALL_SUCCEEDS(lseek, fd_file, 0, SEEK_SET);
116	CHECK_SYSCALL_SUCCEEDS(msync, &fd_file, 8192, MS_ASYNC);
117	CHECK_SYSCALL_SUCCEEDS(profil, NULL, 0, 0, 0);
118	CHECK_SYSCALL_SUCCEEDS(read, fd_file, &ch, sizeof(ch));
119	CHECK_SYSCALL_SUCCEEDS(recvfrom, fd_socket, NULL, 0, 0, NULL, NULL);
120	CHECK_SYSCALL_SUCCEEDS(setuid, getuid());
121	CHECK_SYSCALL_SUCCEEDS(write, fd_file, &ch, sizeof(ch));
122
123	/*
124	 * These calls will fail for lack of e.g. a proper name to send to,
125	 * but they are allowed in capability mode, so errno != ECAPMODE.
126	 */
127	CHECK_NOT_CAPMODE(accept, fd_socket, NULL, NULL);
128	CHECK_NOT_CAPMODE(getpeername, fd_socket, NULL, NULL);
129	CHECK_NOT_CAPMODE(getsockname, fd_socket, NULL, NULL);
130	CHECK_NOT_CAPMODE(fchflags, fd_file, UF_NODUMP);
131	CHECK_NOT_CAPMODE(recvmsg, fd_socket, NULL, 0);
132	CHECK_NOT_CAPMODE(sendmsg, fd_socket, NULL, 0);
133	CHECK_NOT_CAPMODE(sendto, fd_socket, NULL, 0, 0, NULL, 0);
134
135	/*
136	 * System calls which should be allowed in capability mode, but which
137	 * don't return errors, and are thus difficult to check.
138	 *
139	 * We will try anyway, by checking errno.
140	 */
141	CHECK_SYSCALL_VOID_NOT_ECAPMODE(getegid);
142	CHECK_SYSCALL_VOID_NOT_ECAPMODE(geteuid);
143	CHECK_SYSCALL_VOID_NOT_ECAPMODE(getgid);
144	CHECK_SYSCALL_VOID_NOT_ECAPMODE(getpid);
145	CHECK_SYSCALL_VOID_NOT_ECAPMODE(getppid);
146	CHECK_SYSCALL_VOID_NOT_ECAPMODE(getuid);
147
148	/*
149	 * Finally, tests for system calls that don't fit the pattern very well.
150	 */
151	pid = fork();
152	if (pid >= 0) {
153		if (pid == 0) {
154			exit(0);
155		} else if (pid > 0) {
156			wpid = waitpid(pid, NULL, 0);
157			if (wpid < 0) {
158				if (errno != ECAPMODE)
159					FAIL("capmode:waitpid");
160			} else
161				FAIL("capmode:waitpid succeeded");
162		}
163	} else
164		FAIL("capmode:fork");
165
166	if (getlogin() == NULL)
167		FAIL("test_sycalls:getlogin %d", errno);
168
169	if (getsockname(fd_socket, NULL, NULL) < 0) {
170		if (errno == ECAPMODE)
171			FAIL("capmode:getsockname");
172	}
173
174	/* XXXRW: ktrace */
175
176	if (pipe(fd2) == 0) {
177		close(fd2[0]);
178		close(fd2[1]);
179	} else if (errno == ECAPMODE)
180		FAIL("capmode:pipe");
181
182	/* XXXRW: ptrace. */
183
184	/* sysarch() is, by definition, architecture-dependent */
185#if defined (__amd64__) || defined (__i386__)
186	CHECK_CAPMODE(sysarch, I386_SET_IOPERM, &sysarch_arg);
187#else
188	/* XXXJA: write a test for arm */
189	FAIL("capmode:no sysarch() test for current architecture");
190#endif
191
192	/* XXXRW: No error return from sync(2) to test. */
193
194	return (success);
195}
196