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
27 #define UMASK 022
28
29 /*
30 * Github Issue #746 describes a problem in which hardlink targets are
31 * not adequately checked and can be used to modify entries outside of
32 * the sandbox.
33 */
34
35 /*
36 * Verify that ARCHIVE_EXTRACT_SECURE_NODOTDOT disallows '..' in hardlink
37 * targets.
38 */
DEFINE_TEST(test_write_disk_secure746a)39 DEFINE_TEST(test_write_disk_secure746a)
40 {
41 struct archive *a;
42 struct archive_entry *ae;
43
44 /* Start with a known umask. */
45 assertUmask(UMASK);
46
47 /* The target directory we're going to try to affect. */
48 assertMakeDir("target", 0700);
49 assertMakeFile("target/foo", 0700, "unmodified");
50
51 /* The sandbox dir we're going to work within. */
52 assertMakeDir("sandbox", 0700);
53 assertChdir("sandbox");
54
55 /* Create an archive_write_disk object. */
56 assert((a = archive_write_disk_new()) != NULL);
57 archive_write_disk_set_options(a, ARCHIVE_EXTRACT_SECURE_NODOTDOT);
58
59 /* Attempt to hardlink to the target directory. */
60 assert((ae = archive_entry_new()) != NULL);
61 archive_entry_copy_pathname(ae, "bar");
62 archive_entry_set_mode(ae, AE_IFREG | 0777);
63 archive_entry_set_size(ae, 8);
64 archive_entry_copy_hardlink(ae, "../target/foo");
65 assertEqualInt(ARCHIVE_FAILED, archive_write_header(a, ae));
66 assertEqualInt(ARCHIVE_FATAL, archive_write_data(a, "modified", 8));
67 archive_entry_free(ae);
68
69 /* Verify that target file contents are unchanged. */
70 assertTextFileContents("unmodified", "../target/foo");
71
72 assertEqualIntA(a, ARCHIVE_FATAL, archive_write_close(a));
73 archive_write_free(a);
74 }
75
76 /*
77 * Verify that ARCHIVE_EXTRACT_SECURE_NOSYMLINK disallows symlinks in hardlink
78 * targets.
79 */
DEFINE_TEST(test_write_disk_secure746b)80 DEFINE_TEST(test_write_disk_secure746b)
81 {
82 struct archive *a;
83 struct archive_entry *ae;
84
85 if (!canSymlink()) {
86 skipping("Can't test symlinks on this filesystem");
87 return;
88 }
89
90 /* Start with a known umask. */
91 assertUmask(UMASK);
92
93 /* The target directory we're going to try to affect. */
94 assertMakeDir("target", 0700);
95 assertMakeFile("target/foo", 0700, "unmodified");
96
97 /* The sandbox dir we're going to work within. */
98 assertMakeDir("sandbox", 0700);
99 assertChdir("sandbox");
100
101 /* Create an archive_write_disk object. */
102 assert((a = archive_write_disk_new()) != NULL);
103 archive_write_disk_set_options(a, ARCHIVE_EXTRACT_SECURE_SYMLINKS);
104
105 /* Create a symlink to the target directory. */
106 assert((ae = archive_entry_new()) != NULL);
107 archive_entry_copy_pathname(ae, "symlink");
108 archive_entry_set_mode(ae, AE_IFLNK | 0777);
109 archive_entry_copy_symlink(ae, "../target");
110 assertEqualIntA(a, ARCHIVE_OK, archive_write_header(a, ae));
111 archive_entry_free(ae);
112
113 /* Attempt to hardlink to the target directory via the symlink. */
114 assert((ae = archive_entry_new()) != NULL);
115 archive_entry_copy_pathname(ae, "bar");
116 archive_entry_set_mode(ae, AE_IFREG | 0777);
117 archive_entry_set_size(ae, 8);
118 archive_entry_copy_hardlink(ae, "symlink/foo");
119 assertEqualIntA(a, ARCHIVE_FAILED, archive_write_header(a, ae));
120 assertEqualIntA(a, ARCHIVE_FATAL, archive_write_data(a, "modified", 8));
121 archive_entry_free(ae);
122
123 /* Verify that target file contents are unchanged. */
124 assertTextFileContents("unmodified", "../target/foo");
125
126 assertEqualIntA(a, ARCHIVE_FATAL, archive_write_close(a));
127 archive_write_free(a);
128 }
129