/*

    File: file_vault.c

    Copyright (C) 2011 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_vault)
#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"

/*@ requires \valid(file_stat); */
static void register_header_check_vault(file_stat_t *file_stat);

const file_hint_t file_hint_vault = {
  .extension = "vault",
  .description = "McAfee Anti-Theft/FileVault",
  .max_filesize = PHOTOREC_MAX_FILE_SIZE,
  .recover = 1,
  .enable_by_default = 1,
  .register_header_check = &register_header_check_vault
};

/*
 * 03200be0  00 00 00 38 65 31 39 37  34 32 30 2d 39 35 65 34  |...8e197420-95e4|
 * 03200bf0  2d 34 36 33 33 2d 61 33  34 66 2d 34 61 66 64 36  |-4633-a34f-4afd6|
 * 03200c00  30 64 61 62 64 64 37 00                           |0dabdd7.|
 * */

/*@
  @ requires buffer_size >= 2*29;
  @ requires (buffer_size&1)==0;
  @ requires \valid_read(buffer+(0..buffer_size-1));
  @ requires \valid(file_recovery);
  @ requires file_recovery->data_check==&data_check_vault;
  @ requires file_recovery->calculated_file_size <= PHOTOREC_MAX_FILE_SIZE;
  @ requires \separated(buffer, file_recovery);
  @ ensures \result == DC_CONTINUE || \result == DC_STOP;
  @ assigns file_recovery->calculated_file_size;
  @*/
static data_check_t data_check_vault(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
  unsigned int i;
  /*@ loop assigns i, file_recovery->calculated_file_size; */
  for(i = (buffer_size / 2) - 28; i + 29 <= buffer_size; i++)
  {
    if(buffer[i] == '-' && buffer[i + 5] == '-' && buffer[i + 10] == '-' && buffer[i + 15] == '-' && buffer[i + 28] == '\0')
    {
      file_recovery->calculated_file_size = file_recovery->file_size + i + 29 - (buffer_size / 2);
      return DC_STOP;
    }
  }
  file_recovery->calculated_file_size = file_recovery->file_size + (buffer_size / 2);
  return DC_CONTINUE;
}

/*@
  @ requires buffer_size > 0;
  @ requires \valid_read(buffer+(0..buffer_size-1));
  @ requires valid_file_recovery(file_recovery);
  @ requires \valid(file_recovery_new);
  @ requires file_recovery_new->blocksize > 0;
  @ requires separation: \separated(&file_hint_vault, buffer+(..), file_recovery, file_recovery_new);
  @ assigns  *file_recovery_new;
  @ ensures  \result!=0 ==> valid_file_recovery(file_recovery_new);
  @*/
static int header_check_vault(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)
{
  reset_file_recovery(file_recovery_new);
  file_recovery_new->extension = file_hint_vault.extension;
  if(file_recovery_new->blocksize >= 29)
  {
    file_recovery_new->data_check = &data_check_vault;
    file_recovery_new->file_check = &file_check_size;
  }
  return 1;
}

static void register_header_check_vault(file_stat_t *file_stat)
{
  static const unsigned char vault_header[0x12] = {
    'S', 'a', 'f', 'e', 'B', 'o', 'o', 't',
    'E', 'n', 'c', 'V', 'o', 'l', '1', 0x00,
    0x01, 0x01
  };
  register_header_check(0, vault_header, sizeof(vault_header), &header_check_vault, file_stat);
}
#endif