xref: /netbsd-src/external/bsd/libarchive/dist/libarchive/test/test_write_disk_secure746.c (revision 97f7d7b603fb686e31ff0696877e479788d51b37)
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 #if defined(_WIN32) && !defined(__CYGWIN__)
83 	skipping("archive_write_disk security checks not supported on Windows");
84 #elif 0
85 	struct archive *a;
86 	struct archive_entry *ae;
87 
88 	/* Start with a known umask. */
89 	assertUmask(UMASK);
90 
91 	/* The target directory we're going to try to affect. */
92 	assertMakeDir("target", 0700);
93 	assertMakeFile("target/foo", 0700, "unmodified");
94 
95 	/* The sandbox dir we're going to work within. */
96 	assertMakeDir("sandbox", 0700);
97 	assertChdir("sandbox");
98 
99 	/* Create an archive_write_disk object. */
100 	assert((a = archive_write_disk_new()) != NULL);
101 	archive_write_disk_set_options(a, ARCHIVE_EXTRACT_SECURE_SYMLINKS);
102 
103 	/* Create a symlink to the target directory. */
104 	assert((ae = archive_entry_new()) != NULL);
105 	archive_entry_copy_pathname(ae, "symlink");
106 	archive_entry_set_mode(ae, AE_IFLNK | 0777);
107 	archive_entry_copy_symlink(ae, "../target");
108 	assertEqualIntA(a, ARCHIVE_OK, archive_write_header(a, ae));
109 	archive_entry_free(ae);
110 
111 	/* Attempt to hardlink to the target directory via the symlink. */
112 	assert((ae = archive_entry_new()) != NULL);
113 	archive_entry_copy_pathname(ae, "bar");
114 	archive_entry_set_mode(ae, AE_IFREG | 0777);
115 	archive_entry_set_size(ae, 8);
116 	archive_entry_copy_hardlink(ae, "symlink/foo");
117 	assertEqualIntA(a, ARCHIVE_FAILED, archive_write_header(a, ae));
118 	assertEqualIntA(a, ARCHIVE_FATAL, archive_write_data(a, "modified", 8));
119 	archive_entry_free(ae);
120 
121 	/* Verify that target file contents are unchanged. */
122 	assertTextFileContents("unmodified", "../target/foo");
123 
124 	assertEqualIntA(a, ARCHIVE_FATAL, archive_write_close(a));
125 	archive_write_free(a);
126 #endif
127 }
128