1 /*
2
3 File: file_class.c
4
5 Copyright (C) 2009 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 "common.h"
32 #include "filegen.h"
33
34 static void register_header_check_class(file_stat_t *file_stat);
35 static int header_check_class(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);
36
37 const file_hint_t file_hint_class= {
38 .extension="class",
39 .description="Java Class",
40 .max_filesize=PHOTOREC_MAX_FILE_SIZE,
41 .recover=1,
42 .enable_by_default=1,
43 .register_header_check=®ister_header_check_class
44 };
45
46 /* http://en.wikipedia.org/wiki/Class_(file_format) */
47 static const unsigned char class_magic[4]= { 0xCA, 0xFE, 0xBA, 0xBE };
48
49 struct class_header {
50 uint32_t magic_number;
51 uint16_t minor_version;
52 uint16_t major_version;
53 uint16_t constant_pool_count;
54 };
55
register_header_check_class(file_stat_t * file_stat)56 static void register_header_check_class(file_stat_t *file_stat)
57 {
58 register_header_check(0, class_magic, sizeof(class_magic), &header_check_class, file_stat);
59 }
60
header_check_class(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)61 static int header_check_class(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)
62 {
63 const struct class_header *cafe=(const struct class_header *)buffer;
64 if(be32(cafe->magic_number)==0xCafeBabe &&
65 be16(cafe->major_version) >= 45 && be16(cafe->major_version) <= 100 &&
66 be16(cafe->constant_pool_count) > 0)
67 {
68 reset_file_recovery(file_recovery_new);
69 file_recovery_new->extension=file_hint_class.extension;
70 return 1;
71 }
72 return 0;
73 }
74