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
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/* vi: set sw=4 ts=4: */
/* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
* FIXME:
* In privileged mode if uname and gname map to a uid and gid then use the
* mapped value instead of the uid/gid values in tar header
*
* References:
* GNU tar and star man pages,
* Opengroup's ustar interchange format,
* http://www.opengroup.org/onlinepubs/007904975/utilities/pax.html
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/sysmacros.h> /* For makedev */
#include "unarchive.h"
#include "libbb.h"
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
static char *longname = NULL;
static char *linkname = NULL;
#endif
char get_header_tar(archive_handle_t *archive_handle)
{
file_header_t *file_header = archive_handle->file_header;
union {
/* ustar header, Posix 1003.1 */
unsigned char raw[512];
struct {
char name[100]; /* 0-99 */
char mode[8]; /* 100-107 */
char uid[8]; /* 108-115 */
char gid[8]; /* 116-123 */
char size[12]; /* 124-135 */
char mtime[12]; /* 136-147 */
char chksum[8]; /* 148-155 */
char typeflag; /* 156-156 */
char linkname[100]; /* 157-256 */
char magic[6]; /* 257-262 */
char version[2]; /* 263-264 */
char uname[32]; /* 265-296 */
char gname[32]; /* 297-328 */
char devmajor[8]; /* 329-336 */
char devminor[8]; /* 337-344 */
char prefix[155]; /* 345-499 */
char padding[12]; /* 500-512 */
} formated;
} tar;
long sum = 0;
long i;
static int end = 0;
/* Align header */
data_align(archive_handle, 512);
if (bb_full_read(archive_handle->src_fd, tar.raw, 512) != 512) {
/* Assume end of file */
bb_error_msg_and_die("Short header");
//return(EXIT_FAILURE);
}
archive_handle->offset += 512;
/* If there is no filename its an empty header */
if (tar.formated.name[0] == 0) {
if (end) {
/* This is the second consecutive empty header! End of archive!
* Read until the end to empty the pipe from gz or bz2
*/
while (bb_full_read(archive_handle->src_fd, tar.raw, 512) == 512);
return(EXIT_FAILURE);
}
end = 1;
return(EXIT_SUCCESS);
}
end = 0;
/* Check header has valid magic, "ustar" is for the proper tar
* 0's are for the old tar format
*/
if (strncmp(tar.formated.magic, "ustar", 5) != 0) {
#ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATIBILITY
if (strncmp(tar.formated.magic, "\0\0\0\0\0", 5) != 0)
#endif
bb_error_msg_and_die("Invalid tar magic");
}
/* Do checksum on headers */
for (i = 0; i < 148 ; i++) {
sum += tar.raw[i];
}
sum += ' ' * 8;
for (i = 156; i < 512 ; i++) {
sum += tar.raw[i];
}
if (sum != strtol(tar.formated.chksum, NULL, 8)) {
bb_error_msg("Invalid tar header checksum");
return(EXIT_FAILURE);
}
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
if (longname) {
file_header->name = longname;
longname = NULL;
}
else if (linkname) {
file_header->name = linkname;
linkname = NULL;
} else
#endif
{
file_header->name = bb_xstrndup(tar.formated.name,100);
if (tar.formated.prefix[0]) {
char *temp = file_header->name;
file_header->name = concat_path_file(tar.formated.prefix, temp);
free(temp);
}
}
file_header->uid = strtol(tar.formated.uid, NULL, 8);
file_header->gid = strtol(tar.formated.gid, NULL, 8);
file_header->size = strtol(tar.formated.size, NULL, 8);
file_header->mtime = strtol(tar.formated.mtime, NULL, 8);
file_header->link_name = (tar.formated.linkname[0] != '\0') ?
bb_xstrdup(tar.formated.linkname) : NULL;
file_header->device = makedev(strtol(tar.formated.devmajor, NULL, 8),
strtol(tar.formated.devminor, NULL, 8));
/* Set bits 0-11 of the files mode */
file_header->mode = 07777 & strtol(tar.formated.mode, NULL, 8);
/* Set bits 12-15 of the files mode */
switch (tar.formated.typeflag) {
/* busybox identifies hard links as being regular files with 0 size and a link name */
case '1':
file_header->mode |= S_IFREG;
break;
case 'x':
case 'g':
bb_error_msg_and_die("pax is not tar");
break;
case '7':
/* Reserved for high performance files, treat as normal file */
case 0:
case '0':
#ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATIBILITY
if (last_char_is(file_header->name, '/')) {
file_header->mode |= S_IFDIR;
} else
#endif
file_header->mode |= S_IFREG;
break;
case '2':
file_header->mode |= S_IFLNK;
break;
case '3':
file_header->mode |= S_IFCHR;
break;
case '4':
file_header->mode |= S_IFBLK;
break;
case '5':
file_header->mode |= S_IFDIR;
break;
case '6':
file_header->mode |= S_IFIFO;
break;
#ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS
case 'L': {
longname = xzalloc(file_header->size + 1);
archive_xread_all(archive_handle, longname, file_header->size);
archive_handle->offset += file_header->size;
return(get_header_tar(archive_handle));
}
case 'K': {
linkname = xzalloc(file_header->size + 1);
archive_xread_all(archive_handle, linkname, file_header->size);
archive_handle->offset += file_header->size;
file_header->name = linkname;
return(get_header_tar(archive_handle));
}
case 'D': /* GNU dump dir */
case 'M': /* Continuation of multi volume archive*/
case 'N': /* Old GNU for names > 100 characters */
case 'S': /* Sparse file */
case 'V': /* Volume header */
bb_error_msg("Ignoring GNU extension type %c", tar.formated.typeflag);
#endif
default:
bb_error_msg("Unknown typeflag: 0x%x", tar.formated.typeflag);
}
{ /* Strip trailing '/' in directories */
/* Must be done after mode is set as '/' is used to check if its a directory */
char *tmp = last_char_is(file_header->name, '/');
if (tmp) {
*tmp = '\0';
}
}
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_header(archive_handle->file_header);
archive_handle->flags |= ARCHIVE_EXTRACT_QUIET;
archive_handle->action_data(archive_handle);
llist_add_to(&(archive_handle->passed), file_header->name);
} else {
data_skip(archive_handle);
}
archive_handle->offset += file_header->size;
free(file_header->link_name);
return(EXIT_SUCCESS);
}
|
