summaryrefslogtreecommitdiff
path: root/archival/libunarchive/get_header_tar.c
blob: 20451d99674882f1c05a9f701fb8e106294f656b (plain)
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
/*
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Library General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "unarchive.h"
#include "libbb.h"

extern char get_header_tar(archive_handle_t *archive_handle)
{
	file_header_t *file_header = archive_handle->file_header;
	union {
		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;
	char *tmp;

	/* Align header */
	data_align(archive_handle, 512);

	if (archive_xread_all_eof(archive_handle, tar.raw, 512) == 0) {
		/* End of file */
		return(EXIT_FAILURE);
	}
	archive_handle->offset += 512;

	/* If there is no filename its an empty header */
	if (tar.formated.name[0] == 0) {
		return(EXIT_SUCCESS);
	}

	/* 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_OLD_FORMAT
		if (strncmp(tar.formated.magic, "\0\0\0\0\0", 5) != 0)
#endif
			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)) {
		error_msg("Invalid tar header checksum");
		return(EXIT_FAILURE);
	}

	/* convert to type'ed variables */
	if (tar.formated.prefix[0] == 0) {
		file_header->name = strdup(tar.formated.name);
	} else {
		file_header->name = concat_path_file(tar.formated.prefix, tar.formated.name);
	}
	tmp = last_char_is(archive_handle->file_header->name, '/');
	if (tmp) {
		*tmp = '\0';
	}

	file_header->mode = strtol(tar.formated.mode, NULL, 8);
	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') ? 
	    xstrdup(tar.formated.linkname) : NULL;
	file_header->device = (dev_t) ((strtol(tar.formated.devmajor, NULL, 8) << 8) +
				 strtol(tar.formated.devminor, NULL, 8));

#if defined CONFIG_FEATURE_TAR_OLD_FORMAT || defined CONFIG_FEATURE_GNUTAR_LONG_FILENAME
	/* Fix mode, used by the old format */
	switch (tar.formated.typeflag) {
# ifdef CONFIG_FEATURE_TAR_OLD_FORMAT
	case 0:
		file_header->mode |= S_IFREG;
		break;
	case 1:
		error_msg("Internal hard link not supported");
		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;
# endif
# ifdef CONFIG_FEATURE_GNUTAR_LONG_FILENAME
	case 'L': {
			char *longname;

			longname = xmalloc(file_header->size + 1);
			archive_xread_all(archive_handle, longname, file_header->size);
			longname[file_header->size] = '\0';
			archive_handle->offset += file_header->size;

			get_header_tar(archive_handle);
			file_header->name = longname;
			break;
		}
	case 'K': {
			char *linkname;

			linkname = xmalloc(file_header->size + 1);
			archive_xread_all(archive_handle, linkname, file_header->size);
			linkname[file_header->size] = '\0';
			archive_handle->offset += file_header->size;

			get_header_tar(archive_handle);
			file_header->name = linkname;
			break;
		}
# endif
	}
#endif
	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);
		archive_handle->passed = add_to_list(archive_handle->passed, archive_handle->file_header->name);
	} else {
		data_skip(archive_handle);			
	}
	archive_handle->offset += file_header->size;

	return(EXIT_SUCCESS);
}