1 /*
2
3 File: file_arj.c
4
5 Copyright (C) 2008 Christophe GRENIER <grenier@cgsecurity.org>
6
7 This software is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License along
18 with this program; if not, write the Free Software Foundation, Inc., 51
19 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20
21 */
22
23 #ifdef HAVE_CONFIG_H
24 #include <config.h>
25 #endif
26 #ifdef HAVE_STRING_H
27 #include <string.h>
28 #endif
29 #include <stdio.h>
30 #include "types.h"
31 #include "filegen.h"
32 #include "common.h"
33
34 static void register_header_check_arj(file_stat_t *file_stat);
35
36 const file_hint_t file_hint_arj= {
37 .extension="arj",
38 .description="ARJ archive",
39 .max_filesize=PHOTOREC_MAX_SIZE_32,
40 .recover=1,
41 .enable_by_default=1,
42 .register_header_check=®ister_header_check_arj
43 };
44
45 /*
46 * 60 ea 24 00 22 0b 01 02 10 00 02 XX XX XX 50 48
47 * ID HS FH V V OS FL SV FT R DATE/TIME
48 *
49 * Extract from "ARJ TECHNICAL INFORMATION April 1993"
50 http://datacompression.info/ArchiveFormats/arj.txt
51 Structure of main header (low order byte first):
52
53 Bytes Description
54 -------------------------------------------------------------------
55 2 header id (main and local file) = 0x60 0xEA
56 2 basic header size (from 'first_hdr_size' thru 'comment' below)
57 = first_hdr_size + strlen(filename) + 1 + strlen(comment) + 1
58 = 0 if end of archive
59 maximum header size is 2600
60
61 1 first_hdr_size (size up to and including 'extra data')
62 1 archiver version number
63 1 minimum archiver version to extract
64 1 host OS (0 = MSDOS, 1 = PRIMOS, 2 = UNIX, 3 = AMIGA, 4 = MAC-OS)
65 (5 = OS/2, 6 = APPLE GS, 7 = ATARI ST, 8 = NEXT)
66 (9 = VAX VMS)
67 1 arj flags
68 (0x01 = NOT USED)
69 (0x02 = OLD_SECURED_FLAG)
70 (0x04 = VOLUME_FLAG) indicates presence of succeeding
71 volume
72 (0x08 = NOT USED)
73 (0x10 = PATHSYM_FLAG) indicates archive name translated
74 ("\" changed to "/")
75 (0x20 = BACKUP_FLAG) indicates backup type archive
76 (0x40 = SECURED_FLAG)
77 1 security version (2 = current)
78 1 file type (must equal 2)
79 1 reserved
80 4 date time when original archive was created
81 4 date time when archive was last modified
82 4 archive size (currently used only for secured archives)
83 4 security envelope file position
84 2 filespec position in filename
85 2 length in bytes of security envelope data
86 2 (currently not used)
87 ? (currently none)
88
89 ? filename of archive when created (null-terminated string)
90 ? archive comment (null-terminated string)
91
92 4 basic header CRC
93
94 2 1st extended header size (0 if none)
95 ? 1st extended header (currently not used)
96 4 1st extended header's CRC (not present when 0 extended header size)
97 */
98 struct arj_main_header {
99 uint16_t header_id;
100 uint16_t basic_header_size;
101 uint8_t first_header_size;
102 uint8_t archiver_ver;
103 uint8_t archiver_ver_min;
104 uint8_t host_os;
105 uint8_t flags;
106 uint8_t security_ver;
107 uint8_t file_type;
108 uint8_t reserved;
109 uint32_t ctime;
110 uint32_t mtime;
111 uint32_t size;
112 uint32_t security_env_pos;
113 uint16_t filespec_pos;
114 uint16_t security_env_size;
115 uint16_t unused;
116 char filename;
117 } __attribute__ ((gcc_struct, __packed__));
118
file_check_arj(file_recovery_t * file_recovery)119 static void file_check_arj(file_recovery_t *file_recovery)
120 {
121 static const unsigned char arj_footer[4]={0x60, 0xEA, 0x00, 0x00 };
122 file_search_footer(file_recovery, arj_footer, sizeof(arj_footer), 0);
123 }
124
header_check_arj(const unsigned char * buffer,const unsigned int buffer_size,const unsigned int safe_header_only,const file_recovery_t * file_recovery,file_recovery_t * file_recovery_new)125 static int header_check_arj(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new)
126 {
127 const struct arj_main_header *arj=(const struct arj_main_header*)buffer;
128 if(le16(arj->basic_header_size) > 0 &&
129 le16(arj->basic_header_size) <= 2600 &&
130 arj->archiver_ver_min <= arj->archiver_ver &&
131 arj->archiver_ver <=12 &&
132 (arj->flags&0x01)==0 &&
133 arj->file_type==2)
134 {
135 if((arj->flags&0x040)!=0)
136 {
137 if(le32(arj->size) < sizeof(struct arj_main_header))
138 return 0;
139 reset_file_recovery(file_recovery_new);
140 file_recovery_new->calculated_file_size=le32(arj->size);
141 file_recovery_new->data_check=&data_check_size;
142 file_recovery_new->file_check=&file_check_size;
143 }
144 else
145 {
146 // if(le32(arj->size)!=0)
147 // return 0;
148 reset_file_recovery(file_recovery_new);
149 file_recovery_new->file_check=&file_check_arj;
150 }
151 file_recovery_new->extension=file_hint_arj.extension;
152 file_recovery_new->time=le32(arj->ctime);
153 if(file_recovery_new->time < le32(arj->mtime))
154 file_recovery_new->time=le32(arj->mtime);
155 return 1;
156 }
157 return 0;
158 }
159
register_header_check_arj(file_stat_t * file_stat)160 static void register_header_check_arj(file_stat_t *file_stat)
161 {
162 static const unsigned char arj_header[2]={0x60, 0xEA};
163 register_header_check(0, arj_header,sizeof(arj_header), &header_check_arj, file_stat);
164 }
165