summaryrefslogtreecommitdiffstats
path: root/src/file_gsm.c
blob: 7955344374c1047d10ed1e354eee3b3bbf005294 (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
/*

    File: file_gsm.c

    Copyright (C) 2014 Christophe GRENIER <grenier@cgsecurity.org>
  
    This software 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 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 the Free Software Foundation, Inc., 51
    Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <stdio.h>
#include "types.h"
#include "filegen.h"
#include "common.h"
#include "log.h"
#include "memmem.h"

static void register_header_check_gsm(file_stat_t *file_stat);

const file_hint_t file_hint_gsm= {
  .extension="gsm",
  .description="Group Speciale Mobile GSM 06.10",
  .max_filesize=PHOTOREC_MAX_FILE_SIZE,
  .recover=1,
  .enable_by_default=0,
  .register_header_check=&register_header_check_gsm
};

struct block_header
{
  unsigned char marker;
  unsigned char payload[32];
} __attribute__ ((gcc_struct, __packed__));

static data_check_t data_check_gsm(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
  while(file_recovery->calculated_file_size + buffer_size/2  >= file_recovery->file_size &&
      file_recovery->calculated_file_size + sizeof(struct block_header) < file_recovery->file_size + buffer_size/2)
  {
    const unsigned int i=file_recovery->calculated_file_size - file_recovery->file_size + buffer_size/2;
    const struct block_header *hdr=(const struct block_header *)&buffer[i];
    if(hdr->marker < 0xd0 || hdr->marker > 0xdf)
      return DC_STOP;
    file_recovery->calculated_file_size+=sizeof(struct block_header);
  }
  return DC_CONTINUE;
}

static int header_check_gsm(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)
{
  const struct block_header *hdr;
  unsigned int i=0;
  for(i=0, hdr=(const struct block_header *)buffer;
      i * sizeof(struct block_header) < file_recovery_new->blocksize;
      i++, hdr++)
  {
    if(hdr->marker < 0xd0 || hdr->marker > 0xdf)
      return 0;
  }
  if(i<3)
    return 0;
  if(file_recovery->file_stat!=NULL
      &&  file_recovery->file_stat->file_hint==&file_hint_gsm)
  {
    header_ignored(file_recovery_new);
    return 0;
  }
  reset_file_recovery(file_recovery_new);
  file_recovery_new->extension=file_hint_gsm.extension;
  file_recovery_new->min_filesize=sizeof(struct block_header);
  file_recovery_new->calculated_file_size=0;
  file_recovery_new->data_check=&data_check_gsm;
  file_recovery_new->file_check=&file_check_size;
  return 1;
}

static void register_header_check_gsm(file_stat_t *file_stat)
{
  static const unsigned char gsm_header1[1]={ 0xd0 };
  static const unsigned char gsm_header2[1]={ 0xd1 };
  static const unsigned char gsm_header3[1]={ 0xd2 };
  static const unsigned char gsm_header4[1]={ 0xd3 };
  static const unsigned char gsm_header5[1]={ 0xd4 };
  static const unsigned char gsm_header6[1]={ 0xd5 };
  static const unsigned char gsm_header7[1]={ 0xd6 };
  static const unsigned char gsm_header8[1]={ 0xd7 };
  static const unsigned char gsm_header9[1]={ 0xd8 };
  static const unsigned char gsm_header10[1]={ 0xd9 };
  static const unsigned char gsm_header11[1]={ 0xda };
  static const unsigned char gsm_header12[1]={ 0xdb };
  static const unsigned char gsm_header13[1]={ 0xdc };
  static const unsigned char gsm_header14[1]={ 0xdd };
  static const unsigned char gsm_header15[1]={ 0xde };
  static const unsigned char gsm_header16[1]={ 0xdf };

  register_header_check(0, gsm_header1, sizeof(gsm_header1), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header2, sizeof(gsm_header2), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header3, sizeof(gsm_header3), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header4, sizeof(gsm_header4), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header5, sizeof(gsm_header5), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header6, sizeof(gsm_header6), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header7, sizeof(gsm_header7), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header8, sizeof(gsm_header8), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header9, sizeof(gsm_header9), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header10, sizeof(gsm_header10), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header11, sizeof(gsm_header11), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header12, sizeof(gsm_header12), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header13, sizeof(gsm_header13), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header14, sizeof(gsm_header14), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header15, sizeof(gsm_header15), &header_check_gsm, file_stat);
  register_header_check(0, gsm_header16, sizeof(gsm_header16), &header_check_gsm, file_stat);
}