test_write_disk_secure745.c revision 305188 
1/*-
2 * Copyright (c) 2003-2007,2016 Tim Kientzle
3 * All rights reserved.
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(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25#include "test.h"
26__FBSDID("$FreeBSD: stable/11/contrib/libarchive/libarchive/test/test_write_disk_secure745.c 305188 2016-09-01 07:53:59Z mm $");
27
28#define UMASK 022
29
30/*
31 * Github Issue #745 describes a bug in the sandboxing code that
32 * allows one to use a symlink to edit the permissions on a file or
33 * directory outside of the sandbox.
34 */
35
36DEFINE_TEST(test_write_disk_secure745)
37{
38#if defined(_WIN32) && !defined(__CYGWIN__)
39	skipping("archive_write_disk security checks not supported on Windows");
40#else
41	struct archive *a;
42	struct archive_entry *ae;
43
44	/* Start with a known umask. */
45	assertUmask(UMASK);
46
47	/* Create an archive_write_disk object. */
48	assert((a = archive_write_disk_new()) != NULL);
49	archive_write_disk_set_options(a, ARCHIVE_EXTRACT_SECURE_SYMLINKS);
50
51	/* The target dir:  The one we're going to try to change permission on */
52	assertMakeDir("target", 0700);
53
54	/* The sandbox dir we're going to run inside of. */
55	assertMakeDir("sandbox", 0700);
56	assertChdir("sandbox");
57
58	/* Create a symlink pointing to the target directory */
59	assert((ae = archive_entry_new()) != NULL);
60	archive_entry_copy_pathname(ae, "sym");
61	archive_entry_set_mode(ae, S_IFREG | 0777);
62	archive_entry_copy_symlink(ae, "../target");
63	assert(0 == archive_write_header(a, ae));
64	archive_entry_free(ae);
65
66	/* Try to alter the target dir through the symlink; this should fail. */
67	assert((ae = archive_entry_new()) != NULL);
68	archive_entry_copy_pathname(ae, "sym");
69	archive_entry_set_mode(ae, S_IFDIR | 0777);
70	assert(0 == archive_write_header(a, ae));
71	archive_entry_free(ae);
72
73	/* Permission of target dir should not have changed. */
74	assertFileMode("../target", 0700);
75#endif
76}
77