testdisk/src/file_dv.c

235 lines
7.7 KiB
C

/*
File: file_dv.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_dv)
#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"
#if defined(__FRAMAC__)
#include "__fc_builtin.h"
#endif
/*@ requires valid_register_header_check(file_stat); */
static void register_header_check_dv(file_stat_t *file_stat);
const file_hint_t file_hint_dv= {
.extension="dv",
.description="DIF Digital Video",
.max_filesize=PHOTOREC_MAX_FILE_SIZE,
.recover=1,
.enable_by_default=1,
.register_header_check=&register_header_check_dv
};
/*@
@ requires file_recovery->data_check==&data_check_NTSC;
@ requires valid_data_check_param(buffer, buffer_size, file_recovery);
@ ensures valid_data_check_result(\result, file_recovery);
@ assigns file_recovery->calculated_file_size;
@*/
static data_check_t data_check_NTSC(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
/*@ assert file_recovery->calculated_file_size <= PHOTOREC_MAX_FILE_SIZE; */
/*@ assert file_recovery->file_size <= PHOTOREC_MAX_FILE_SIZE; */
/*@
@ loop assigns file_recovery->calculated_file_size;
@*/
while(file_recovery->calculated_file_size + buffer_size/2 >= file_recovery->file_size &&
file_recovery->calculated_file_size + 8 < file_recovery->file_size + buffer_size/2)
{
const unsigned int i=file_recovery->calculated_file_size + buffer_size/2 - file_recovery->file_size;
/*@ assert 0 <= i < buffer_size - 8; */
if(buffer[i]==0x1f && buffer[i+1]==0x07 && buffer[i+2]==0x00 &&
buffer[i+5]==0x78 && buffer[i+6]==0x78 && buffer[i+7]==0x78)
file_recovery->calculated_file_size+=120000;
else
return DC_STOP;
}
return DC_CONTINUE;
}
/*@
@ requires fr->file_check == &file_check_dv_NTSC;
@ requires valid_file_check_param(fr);
@ ensures valid_file_check_result(fr);
@ assigns *fr->handle, errno, Frama_C_entropy_source, fr->file_size;
@*/
static void file_check_dv_NTSC(file_recovery_t *fr)
{
char buffer_header[512];
uint64_t fs=fr->file_size/120000*120000;
if(my_fseek(fr->handle, 0, SEEK_SET) < 0 ||
fread(&buffer_header, sizeof(buffer_header), 1, fr->handle) != 1)
return ;
#if defined(__FRAMAC__)
Frama_C_make_unknown(&buffer_header, sizeof(buffer_header));
#endif
if(fs > 0)
fs-=120000;
if(fs > 0)
fs-=120000;
/*@ loop assigns fs, *fr->handle, errno, Frama_C_entropy_source, fr->file_size; */
while(fs < fr->file_size &&
my_fseek(fr->handle, fs, SEEK_SET) >= 0)
{
char buffer[120000];
unsigned int i;
if(fread(&buffer, sizeof(buffer), 1, fr->handle) != 1)
{
fr->file_size=fs;
return;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown(&buffer, sizeof(buffer));
#endif
/*@ loop assigns i, fr->file_size; */
for(i=1; i<sizeof(buffer); i+=0x50)
if((buffer[i]&0x0f)!=(buffer_header[1]&0x0f))
{
fr->file_size=fs;
return;
}
fs+=sizeof(buffer);
}
fr->file_size=fs;
}
/*@
@ requires file_recovery->data_check==&data_check_PAL;
@ requires valid_data_check_param(buffer, buffer_size, file_recovery);
@ ensures valid_data_check_result(\result, file_recovery);
@ assigns file_recovery->calculated_file_size;
@*/
static data_check_t data_check_PAL(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
/*@ assert file_recovery->file_size <= PHOTOREC_MAX_FILE_SIZE; */
/*@ assert buffer_size <= 2 * PHOTOREC_MAX_BLOCKSIZE; */
/*@
@ loop assigns file_recovery->calculated_file_size;
@*/
while(file_recovery->calculated_file_size + buffer_size/2 >= file_recovery->file_size &&
file_recovery->calculated_file_size + 8 < file_recovery->file_size + buffer_size/2)
{
const unsigned int i=file_recovery->calculated_file_size + buffer_size/2 - file_recovery->file_size;
/*@ assert 0 <= i < buffer_size - 8; */
if(buffer[i]==0x1f && buffer[i+1]==0x07 && buffer[i+2]==0x00 &&
buffer[i+5]==0x78 && buffer[i+6]==0x78 && buffer[i+7]==0x78)
file_recovery->calculated_file_size+=144000;
else
return DC_STOP;
}
return DC_CONTINUE;
}
/*@
@ requires fr->file_check == &file_check_dv_PAL;
@ requires valid_file_check_param(fr);
@ ensures valid_file_check_result(fr);
@ assigns *fr->handle, errno, Frama_C_entropy_source, fr->file_size;
@*/
static void file_check_dv_PAL(file_recovery_t *fr)
{
char buffer_header[512];
uint64_t fs=fr->file_size/144000*144000;
if(my_fseek(fr->handle, 0, SEEK_SET) < 0 ||
fread(&buffer_header, sizeof(buffer_header), 1, fr->handle) != 1)
return ;
#if defined(__FRAMAC__)
Frama_C_make_unknown(&buffer_header, sizeof(buffer_header));
#endif
if(fs > 0)
fs-=144000;
if(fs > 0)
fs-=144000;
/*@ loop assigns fs, *fr->handle, errno, Frama_C_entropy_source, fr->file_size; */
while(fs < fr->file_size &&
my_fseek(fr->handle, fs, SEEK_SET) >= 0)
{
unsigned int i;
char buffer[144000];
if(fread(&buffer, sizeof(buffer), 1, fr->handle) != 1)
{
fr->file_size=fs;
return;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown(&buffer, sizeof(buffer));
#endif
/*@ loop assigns i, fr->file_size; */
for(i=1; i<sizeof(buffer); i+=0x50)
if((buffer[i]&0x0f)!=(buffer_header[1]&0x0f))
{
fr->file_size=fs;
return;
}
fs+=sizeof(buffer);
}
fr->file_size=fs;
}
/*@
@ requires buffer_size >= 8;
@ requires separation: \separated(&file_hint_dv, 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);
@*/
static int header_check_dv(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)
{
if(buffer[0]!=0x1f || buffer[1]!=0x07 || buffer[2]!=0x00 || buffer[5]!=0x78 || buffer[6]!=0x78 || buffer[7]!=0x78)
return 0;
if(file_recovery->file_stat!=NULL &&
file_recovery->file_check!=NULL &&
file_recovery->file_stat->file_hint==&file_hint_dv)
{
/*@ assert \valid_function(file_recovery->file_check); */
header_ignored(file_recovery_new);
return 0;
}
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_dv.extension;
if((buffer[3]&0x80)==0)
file_recovery_new->file_check=&file_check_dv_NTSC;
else
file_recovery_new->file_check=&file_check_dv_PAL;
if(file_recovery_new->blocksize < 8)
return 1;
// Each frame contains exactly 120000 bytes in NTSC, 144000 in PAL.
if((buffer[3]&0x80)==0)
file_recovery_new->data_check=&data_check_NTSC;
else
file_recovery_new->data_check=&data_check_PAL;
return 1;
}
static void register_header_check_dv(file_stat_t *file_stat)
{
static const unsigned char dv_header[3]= {0x1f, 0x07, 0x00};
register_header_check(0, dv_header,sizeof(dv_header), &header_check_dv, file_stat);
}
#endif