/*

    File: btrfs.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.

 */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
 
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include "types.h"
#include "common.h"
#include "btrfs.h"
#include "fnctdsk.h"
#include "log.h"
#include "guid_cpy.h"

static int test_btrfs(const struct btrfs_super_block *sb);

static void set_btrfs_info(const struct btrfs_super_block *sb, partition_t *partition)
{
  partition->upart_type=UP_BTRFS;
  partition->blocksize=le32(sb->dev_item.sector_size);
  set_part_name(partition, sb->label, sizeof(sb->label));
  snprintf(partition->info, sizeof(partition->info), "btrfs blocksize=%u", partition->blocksize);
  if(le64(sb->bytenr)!=partition->part_offset + BTRFS_SUPER_INFO_OFFSET)
  {
    strcat(partition->info," Backup superblock");
  }
  /* last mounted => date */
}

int check_btrfs(disk_t *disk_car,partition_t *partition)
{
  unsigned char *buffer=(unsigned char*)MALLOC(BTRFS_SUPER_INFO_SIZE);
  if(disk_car->pread(disk_car, buffer, BTRFS_SUPER_INFO_SIZE, partition->part_offset + BTRFS_SUPER_INFO_OFFSET) != BTRFS_SUPER_INFO_SIZE)
  {
    free(buffer);
    return 1;
  }
  if(test_btrfs((struct btrfs_super_block*)buffer)!=0)
  {
    free(buffer);
    return 1;
  }
  set_btrfs_info((struct btrfs_super_block*)buffer, partition);
  free(buffer);
  return 0;
}

/*
Primary superblock is at 1024 (SUPERBLOCK_OFFSET)
Group 0 begin at s_first_data_block
*/
int recover_btrfs(const disk_t *disk, const struct btrfs_super_block *sb, partition_t *partition, const int verbose, const int dump_ind)
{
  if(test_btrfs(sb)!=0)
    return 1;
  if(dump_ind!=0)
  {
    if(partition!=NULL && disk!=NULL)
      log_info("\nbtrfs magic value at %u/%u/%u\n",
	  offset2cylinder(disk,partition->part_offset),
	  offset2head(disk,partition->part_offset),
	  offset2sector(disk,partition->part_offset));
    dump_log(sb, BTRFS_SUPER_INFO_SIZE);
  }
  if(partition==NULL)
    return 0;
  set_btrfs_info(sb, partition);
  partition->part_type_i386=P_LINUX;
  partition->part_type_mac=PMAC_LINUX;
  partition->part_type_sun=PSUN_LINUX;
  partition->part_type_gpt=GPT_ENT_TYPE_LINUX_DATA;
  partition->part_size=(uint64_t)le64(sb->dev_item.total_bytes);
  guid_cpy(&partition->part_uuid, (const efi_guid_t *)&sb->fsid);
  if(verbose>0)
  {
    log_info("\n");
  }
  partition->sborg_offset=BTRFS_SUPER_INFO_OFFSET;
  partition->sb_size=BTRFS_SUPER_INFO_SIZE;
  if(verbose>0)
  {
    if(disk==NULL)
      log_info("recover_btrfs: part_size %lu\n", (long unsigned)(partition->part_size / le32(sb->dev_item.sector_size)));
    else
      log_info("recover_btrfs: part_size %lu\n", (long unsigned)(partition->part_size / disk->sector_size));
  }
  return 0;
}

static int test_btrfs(const struct btrfs_super_block *sb)
{
  if(memcmp(&sb->magic, BTRFS_MAGIC, 8)!=0)
    return 1;
  if(le32(sb->dev_item.sector_size)==0)
    return 1;
  return 0;
}
