2 * Copyright (c) 2006 nCircle Network Security, Inc.
5 * This software was developed by Robert N. M. Watson for the TrustedBSD
6 * Project under contract to nCircle Network Security, Inc.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR, NCIRCLE NETWORK SECURITY,
21 * INC., OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
24 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
25 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
26 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 * Confirm that a generation number isn't returned by stat() when not running
34 * with privilege. In order to differentiate between a generation of 0 and
35 * a generation not being returned, we have to create a temporary file known
36 * to have a non-0 generation. We try up to 10 times, and then give up,
37 * which is non-ideal, but better than not testing for a problem.
50 * Can't use setup_file() since the resulting file needs to have specific
54 priv_vfs_generation(void)
56 char fpath[1024] = "/tmp/priv.XXXXXXXXXX";
63 * Create a file with a non-0 generation number. Try ten times,
64 * which gives a high chance of succeeds, fail otherwise. Not ideal,
65 * since we can't distinguish the file having a generation of 0 from
66 * not being able to query it for access control reasons. The perils
67 * of an API that changes behavior based on lack of privilege rather
70 for (i = 0; i < 10; i++) {
74 if (fstat(fd, &sb) < 0) {
75 warn("fstat(%s)", fpath);
83 strcpy(fpath, "/tmp/generation.XXXXXXXXXX");
88 "could not create file with non-0 generation as root");
92 * We've already tested that fstat() works, but try stat() to be
93 * consistent between privileged and unprivileged tests.
95 if (stat(fpath, &sb) < 0) {
96 warn("stat(%s) as root", fpath);
102 if (stat(fpath, &sb) < 0) {
103 warn("stat(%s) as !root", fpath);
108 warn("stat(%s) returned generation as !root", fpath);
111 (void)seteuid(UID_ROOT);