testdisk/src/file_pct.c
2021-02-27 10:27:22 +01:00

160 lines
5.3 KiB
C

/*
File: file_pct.c
Copyright (C) 2008 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_pct)
#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"
#if !defined(SINGLE_FORMAT)
extern const file_hint_t file_hint_indd;
#endif
/*@ requires \valid(file_stat); */
static void register_header_check_pct(file_stat_t *file_stat);
const file_hint_t file_hint_pct= {
.extension="pct",
.description="Macintosh Picture",
.max_filesize=PHOTOREC_MAX_FILE_SIZE,
.recover=1,
.enable_by_default=1,
.register_header_check=&register_header_check_pct
};
/* We are searching for PICTv2 files
http://www.fileformat.info/format/macpict/
SHORT Version operator (0x0011)
SHORT Version number (0x02ff)
SHORT Header opcode for Version 2 (0C00)
*/
struct pct_file_entry {
uint16_t filesize; /* 0x00 */
uint16_t XMin; /* 0x02 72 DPI */
uint16_t YMin; /* 0x04 */
uint16_t XMax; /* 0x06 */
uint16_t YMax; /* 0x08 */
uint16_t VersionOperator; /* 0x0A 0x0011 */
uint16_t VersionNumber; /* 0x0C 0x02ff */
uint16_t HeaderOpcode; /* 0x0E 0x0C00 */
uint16_t Val; /* 0x10 0xFFEF or 0xFFEE */
uint16_t Reserved; /* 0x12 0x0000 */
uint32_t HDPI; /* 0x14 */
uint32_t VDPI; /* 0x18 */
#if 0
uint16_t OYMax; // pbmplus format
uint16_t OYMin;
uint16_t OXMax;
uint16_t OXMin;
#else
uint16_t OXMin;
uint16_t OYMin;
uint16_t OXMax;
uint16_t OYMax;
#endif
uint32_t Reserved2; /* 0x24 */
} __attribute__ ((gcc_struct, __packed__));
/*@
@ requires \valid(file_recovery);
@ requires valid_file_recovery(file_recovery);
@ requires file_recovery->file_check == &file_check_pct;
@ ensures valid_file_recovery(file_recovery);
@ assigns file_recovery->file_size;
@*/
static void file_check_pct(file_recovery_t *file_recovery)
{
if(file_recovery->file_size<0x210 ||
file_recovery->file_size<file_recovery->min_filesize)
{
file_recovery->file_size=0;
return ;
}
file_recovery->file_size-=((file_recovery->file_size-file_recovery->min_filesize)&0xFFFF);
}
/*@
@ requires buffer_size >= 0x200+sizeof(struct pct_file_entry);
@ 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_pct, buffer+(..), file_recovery, file_recovery_new);
@ ensures \result == 0 || \result == 1;
@ ensures \result!=0 ==> valid_file_recovery(file_recovery_new);
@*/
static int header_check_pct(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 pct_file_entry *pct=(const struct pct_file_entry *)(&buffer[0x200]);
if(be16(pct->XMin) <= be16(pct->XMax) &&
be16(pct->YMin) <= be16(pct->YMax) &&
((be16(pct->OXMin) <= be16(pct->OXMax) &&
be16(pct->OYMin) <= be16(pct->OYMax)) ||
(be16(pct->OYMax) <= be16(pct->OXMax) && /* pbmplus creates boggus files */
be16(pct->OYMin) <= be16(pct->OXMin))) &&
be16(pct->XMin)==0 && /* Reject some valid but uncommon files */
be16(pct->YMin)==0 &&
be16(pct->OYMin)==0 &&
be16(pct->VersionOperator)==0x0011 &&
be16(pct->VersionNumber)==0x02ff)
{
const unsigned int min_filesize=(buffer[0x200]<<8)+buffer[0x201];
#if !defined(SINGLE_FORMAT)
if(file_recovery->file_stat != NULL &&
file_recovery->file_stat->file_hint==&file_hint_indd)
{
if(header_ignored_adv(file_recovery, file_recovery_new)==0)
return 0;
}
#endif
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_pct.extension;
/* We only have the low 16bits of the filesystem */
file_recovery_new->min_filesize=(min_filesize > 0x200+sizeof(struct pct_file_entry) ? min_filesize : 0x200+sizeof(struct pct_file_entry));
file_recovery_new->file_check=&file_check_pct;
#ifdef DEBUG_PCT
log_info("X %u-%u, Y %u-%u\n",
be16(pct->XMin), be16(pct->XMax),
be16(pct->YMin), be16(pct->YMax));
log_info("X %u-%u, Y %u-%u\n",
be16(pct->OXMin), be16(pct->OXMax),
be16(pct->OYMin), be16(pct->OYMax));
#endif
return 1;
}
return 0;
}
static void register_header_check_pct(file_stat_t *file_stat)
{
static const unsigned char pct_header[6]= { 0x00, 0x11, 0x02, 0xff, 0x0c, 0x00};
register_header_check(0x20a, pct_header,sizeof(pct_header), &header_check_pct, file_stat);
}
#endif