summaryrefslogtreecommitdiffstats
path: root/src/file_wim.c
blob: 3221a1e4596f68c61c9fbb357ca1e3d8e899e786 (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
/*

    File: file_wim.c

    Copyright (C) 2012 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.

 */

#if !defined(SINGLE_FORMAT) || defined(SINGLE_FORMAT_wim)
#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"

/*@ requires valid_register_header_check(file_stat); */
static void register_header_check_wim(file_stat_t *file_stat);
/* http://go.microsoft.com/fwlink/?LinkId=92227 */

const file_hint_t file_hint_wim = {
  .extension = "wim",
  .description = "Windows imaging (WIM) image",
  .max_filesize = PHOTOREC_MAX_FILE_SIZE,
  .recover = 1,
  .enable_by_default = 1,
  .register_header_check = &register_header_check_wim
};

struct reshdr_disk_short
{
  union
  {
    uint64_t flags; /* one byte is a combination of RESHDR_FLAG_XXX */
    uint64_t size;  /* the 7 low-bytes are used to store the size */
  };
  uint64_t offset;
  uint64_t original_size;
} __attribute__((gcc_struct, __packed__));

#define RESHDR_GET_SIZE(R) (le64(R.size) & 0x00FFFFFFFFFFFFFF)

struct _WIMHEADER_V1_PACKED
{
  char ImageTag[8];
  uint32_t cbSize;
  uint32_t dwVersion;
  uint32_t dwFlags;
  uint32_t dwCompressionSize;
  unsigned char gWIMGuid[16];
  uint16_t usPartNumber;
  uint16_t usTotalParts;
  uint32_t dwImageCount;
  struct reshdr_disk_short rhOffsetTable;
  struct reshdr_disk_short rhXmlData;
  struct reshdr_disk_short rhBootMetadata;
  uint32_t dwBootIndex;
  struct reshdr_disk_short rhIntegrity;
  unsigned char bUnused[60];
} __attribute__((gcc_struct, __packed__));

/*@
  @ requires size <= 0x00FFFFFFFFFFFFFF;
  @ assigns  \nothing;
  @*/
static uint64_t wim_max(const uint64_t offset, const uint64_t size, const uint64_t max_size)
{
  uint64_t tmp;
  if(size == 0)
    return max_size;
  if(offset > PHOTOREC_MAX_FILE_SIZE)
    return 0;
  tmp = offset + size;
  if(tmp > max_size)
    return tmp;
  return max_size;
}

/*@
  @ requires buffer_size > sizeof(struct _WIMHEADER_V1_PACKED);
  @ requires separation: \separated(&file_hint_wim, buffer+(..), file_recovery, file_recovery_new);
  @ requires valid_header_check_param(buffer, buffer_size, safe_header_only, file_recovery, file_recovery_new);
  @ ensures  valid_header_check_result(\result, file_recovery_new);
  @ assigns  *file_recovery_new;
  @*/
static int header_check_wim(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 _WIMHEADER_V1_PACKED *hdr = (const struct _WIMHEADER_V1_PACKED *)buffer;
  uint64_t size = le32(hdr->cbSize);
  const uint64_t rhOffsetTable_s = RESHDR_GET_SIZE(hdr->rhOffsetTable);
  /*@ assert rhOffsetTable_s <= 0x00FFFFFFFFFFFFFF; */
  const uint64_t rhOffsetTable_o = le64(hdr->rhOffsetTable.offset);
  const uint64_t rhXmlData_s = RESHDR_GET_SIZE(hdr->rhXmlData);
  /*@ assert rhXmlData_s <= 0x00FFFFFFFFFFFFFF; */
  const uint64_t rhXmlData_o = le64(hdr->rhXmlData.offset);
  const uint64_t rhBootMetadata_s = RESHDR_GET_SIZE(hdr->rhBootMetadata);
  /*@ assert rhBootMetadata_s <= 0x00FFFFFFFFFFFFFF; */
  const uint64_t rhBootMetadata_o = le64(hdr->rhBootMetadata.offset);
  const uint64_t rhIntegrity_s = RESHDR_GET_SIZE(hdr->rhIntegrity);
  /*@ assert rhIntegrity_s <= 0x00FFFFFFFFFFFFFF; */
  const uint64_t rhIntegrity_o = le64(hdr->rhIntegrity.offset);

  if(size < sizeof(struct _WIMHEADER_V1_PACKED))
    return 0;
#ifdef DEBUG_WIM
  log_info("cbSize %llu\n", (unsigned long long)size);
  log_info("dwCompressionSize %llu\n", (unsigned long long)le32(hdr->dwCompressionSize));
  log_info("rhOffsetTable %llu %llu\n", (unsigned long long)rhOffsetTable_s, (unsigned long long)rhOffsetTable_o);
  log_info("rhXmlData %llu %llu\n", (unsigned long long)rhXmlData_s, (unsigned long long)rhXmlData_o);
  log_info("rhBootMetadata %llu %llu\n", (unsigned long long)rhBootMetadata_s, (unsigned long long)rhBootMetadata_o);
  log_info("rhIntegrity %llu %llu\n", (unsigned long long)rhIntegrity_s, (unsigned long long)rhIntegrity_o);
#endif
  size = wim_max(rhOffsetTable_o, rhOffsetTable_s, size);
  if(size == 0)
    return 0;
  size = wim_max(rhXmlData_o, rhXmlData_s, size);
  if(size == 0)
    return 0;
  size = wim_max(rhBootMetadata_o, rhBootMetadata_s, size);
  if(size == 0)
    return 0;
  size = wim_max(rhIntegrity_o, rhIntegrity_s, size);
  if(size == 0)
    return 0;
  reset_file_recovery(file_recovery_new);
  file_recovery_new->extension = file_hint_wim.extension;
  file_recovery_new->calculated_file_size = size;
  file_recovery_new->data_check = &data_check_size;
  file_recovery_new->file_check = &file_check_size;
  /*@ assert valid_file_recovery(file_recovery_new); */
  return 1;
}

static void register_header_check_wim(file_stat_t *file_stat)
{
  register_header_check(0, "MSWIM\0\0\0", 8, &header_check_wim, file_stat);
}
#endif