1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
/*
* This file uses XZ Embedded library code which is written
* by Lasse Collin <lasse.collin@tukaani.org>
* and Igor Pavlov <http://7-zip.org/>
*
* See README file in unxz/ directory for more information.
*
* This file is:
* Copyright (C) 2010 Denys Vlasenko <vda.linux@googlemail.com>
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
#include "libbb.h"
#include "bb_archive.h"
#define XZ_FUNC FAST_FUNC
#define XZ_EXTERN static
#define XZ_DEC_DYNALLOC
/* Skip check (rather than fail) of unsupported hash functions */
#define XZ_DEC_ANY_CHECK 1
/* We use our own crc32 function */
#define XZ_INTERNAL_CRC32 0
static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
{
return ~crc32_block_endian0(~crc, buf, size, global_crc32_table);
}
/* We use arch-optimized unaligned fixed-endian accessors.
* They have been moved to libbb (proved to be useful elsewhere as well),
* just check that we have them defined:
*/
#if !defined(get_unaligned_le32) \
|| !defined(get_unaligned_be32) \
|| !defined(put_unaligned_le32) \
|| !defined(put_unaligned_be32)
# error get_unaligned_le32 accessors are not defined
#endif
#include "unxz/xz_dec_bcj.c"
#include "unxz/xz_dec_lzma2.c"
#include "unxz/xz_dec_stream.c"
IF_DESKTOP(long long) int FAST_FUNC
unpack_xz_stream(transformer_state_t *xstate)
{
enum xz_ret xz_result;
struct xz_buf iobuf;
struct xz_dec *state;
unsigned char *membuf;
IF_DESKTOP(long long) int total = 0;
if (!global_crc32_table)
global_crc32_new_table_le();
memset(&iobuf, 0, sizeof(iobuf));
membuf = xmalloc(2 * BUFSIZ);
iobuf.in = membuf;
iobuf.out = membuf + BUFSIZ;
iobuf.out_size = BUFSIZ;
if (!xstate || xstate->signature_skipped) {
/* Preload XZ file signature */
strcpy((char*)membuf, HEADER_MAGIC);
iobuf.in_size = HEADER_MAGIC_SIZE;
} /* else: let xz code read & check it */
/* Limit memory usage to about 64 MiB. */
state = xz_dec_init(XZ_DYNALLOC, 64*1024*1024);
xz_result = X_OK;
while (1) {
if (iobuf.in_pos == iobuf.in_size) {
int rd = safe_read(xstate->src_fd, membuf, BUFSIZ);
if (rd < 0) {
bb_simple_error_msg(bb_msg_read_error);
total = -1;
break;
}
if (rd == 0 && xz_result == XZ_STREAM_END)
break;
iobuf.in_size = rd;
iobuf.in_pos = 0;
}
if (xz_result == XZ_STREAM_END) {
/*
* Try to start decoding next concatenated stream.
* Stream padding must always be a multiple of four
* bytes to preserve four-byte alignment. To keep the
* code slightly smaller, we aren't as strict here as
* the .xz spec requires. We just skip all zero-bytes
* without checking the alignment and thus can accept
* files that aren't valid, e.g. the XZ utils test
* files bad-0pad-empty.xz and bad-0catpad-empty.xz.
*/
do {
if (membuf[iobuf.in_pos] != 0) {
/* There is more data, but is it XZ data?
* Example: dpkg-deb -f busybox_1.30.1-4_amd64.deb
* reads control.tar.xz "control" file
* inside the ar archive, but tar.xz
* extraction code reaches end of xz data,
* reached this code and reads the beginning
* of data.tar.xz's ar header, which isn't xz data,
* and prints "corrupted data".
* The correct solution is to not read
* past nested archive (to simulate EOF).
* This is a workaround:
*/
if (membuf[iobuf.in_pos] != 0xfd) {
/* It's definitely not a xz signature
* (which is 0xfd,"7zXZ",0x00).
*/
goto end;
}
xz_dec_reset(state);
goto do_run;
}
iobuf.in_pos++;
} while (iobuf.in_pos < iobuf.in_size);
}
do_run:
// bb_error_msg(">in pos:%d size:%d out pos:%d size:%d",
// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size);
xz_result = xz_dec_run(state, &iobuf);
// bb_error_msg("<in pos:%d size:%d out pos:%d size:%d r:%d",
// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, xz_result);
if (iobuf.out_pos) {
xtransformer_write(xstate, iobuf.out, iobuf.out_pos);
IF_DESKTOP(total += iobuf.out_pos;)
iobuf.out_pos = 0;
}
if (xz_result == XZ_STREAM_END) {
/*
* Can just "break;" here, if not for concatenated
* .xz streams.
* Checking for padding may require buffer
* replenishment. Can't do it here.
*/
continue;
}
if (xz_result != XZ_OK && xz_result != XZ_UNSUPPORTED_CHECK) {
bb_simple_error_msg("corrupted data");
total = -1;
break;
}
}
end:
xz_dec_end(state);
free(membuf);
return total;
}
|
