/*

    File: file_cwk.c

    Copyright (C) 2006-2007 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_cwk)
#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_cwk(file_stat_t *file_stat);

const file_hint_t file_hint_cwk= {
  .extension="cwk",
  .description="AppleWorks",
  .max_filesize=200*1024*1024,
  .recover=1,
  .enable_by_default=1,
  .register_header_check=&register_header_check_cwk
};

/* http://wiki.wirelust.com/x/index.php/AppleWorks_/_ClarisWorks */
struct cwk_header
{
  unsigned char major_version;
  unsigned char minor_version[3];
  uint32_t	creator_type;	/* BOBO */
  unsigned char old_major_version;
  unsigned char old_minor_version[3];
  uint64_t	reserved0;
  uint16_t	reserved1;
  uint16_t	marker;
  uint16_t	unk1;
  uint32_t	unk2;
  uint16_t	height;
  uint16_t	width;
  uint16_t	margins[6];
  uint16_t	inner_height;
  uint16_t	inner_width;
} __attribute__ ((gcc_struct, __packed__));

/*@
  @ requires file_recovery->file_check == &file_check_cwk;
  @ requires valid_file_check_param(file_recovery);
  @ ensures  valid_file_check_result(file_recovery);
  @ assigns *file_recovery->handle, errno, file_recovery->file_size;
  @ assigns Frama_C_entropy_source;
  @
  @*/
static void file_check_cwk(file_recovery_t *file_recovery)
{
  const unsigned char cwk_footer[4]= {0xf0, 0xf1, 0xf2, 0xf3};
  file_search_footer(file_recovery, cwk_footer, sizeof(cwk_footer), 4);
}

/*@
  @ requires buffer_size >= sizeof(struct cwk_header);
  @ requires separation: \separated(&file_hint_cwk, 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_cwk(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 cwk_header *cwk=(const struct cwk_header *)buffer;
  if(be64(cwk->reserved0)!=0 || be16(cwk->reserved1)!=1)
    return 0;
  reset_file_recovery(file_recovery_new);
  file_recovery_new->extension=file_hint_cwk.extension;
  file_recovery_new->file_check=&file_check_cwk;
  return 1;
}

static void register_header_check_cwk(file_stat_t *file_stat)
{
  static const unsigned char cwk_header[4]= {'B','O','B','O'};
  register_header_check(4, cwk_header,sizeof(cwk_header), &header_check_cwk, file_stat);
}
#endif
