/*

    File: file_xpt.c

    Copyright (C) 2009 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_xpt)
#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"

/*@ requires valid_register_header_check(file_stat); */
static void register_header_check_xpt(file_stat_t *file_stat);

const file_hint_t file_hint_xpt = {
  .extension = "xpt",
  .description = "Mozilla XPCOM Type Library",
  .max_filesize = PHOTOREC_MAX_FILE_SIZE,
  .recover = 1,
  .enable_by_default = 1,
  .register_header_check = &register_header_check_xpt
};

/* Read http://www.mozilla.org/scriptable/typelib_file.html
 * for more information about this file format */
struct TypeLibHeader
{
  char magic[16];
  uint8_t major_version;
  uint8_t minor_version;
  uint16_t num_interfaces;
  uint32_t file_length;
} __attribute__((gcc_struct, __packed__));

/*@
  @ requires buffer_size >= sizeof(struct TypeLibHeader);
  @ requires separation: \separated(&file_hint_xpt, 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_xpt(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 TypeLibHeader *xpt = (const struct TypeLibHeader *)buffer;
  const unsigned int file_length = be32(xpt->file_length);
  if(file_length < 65)
    return 0;
  reset_file_recovery(file_recovery_new);
  file_recovery_new->extension = file_hint_xpt.extension;
  file_recovery_new->min_filesize = 65;
  file_recovery_new->calculated_file_size = file_length;
  file_recovery_new->data_check = &data_check_size;
  file_recovery_new->file_check = &file_check_size;
  return 1;
}

static void register_header_check_xpt(file_stat_t *file_stat)
{
  static const unsigned char xpt_header[16] = {
    'X', 'P', 'C', 'O', 'M', '\n', 'T', 'y',
    'p', 'e', 'L', 'i', 'b', '\r', '\n', 0x1a
  };
  register_header_check(0, xpt_header, sizeof(xpt_header), &header_check_xpt, file_stat);
}
#endif