120 lines
4.4 KiB
C
120 lines
4.4 KiB
C
/*
|
|
|
|
File: file_flac.c
|
|
|
|
Copyright (C) 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_flac)
|
|
#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"
|
|
|
|
/*@ requires valid_register_header_check(file_stat); */
|
|
static void register_header_check_flac(file_stat_t *file_stat);
|
|
|
|
const file_hint_t file_hint_flac= {
|
|
.extension="flac",
|
|
.description="FLAC audio",
|
|
.max_filesize=(uint64_t)1500*1024*1024,
|
|
.recover=1,
|
|
.enable_by_default=1,
|
|
.register_header_check=®ister_header_check_flac
|
|
};
|
|
|
|
/* https://xiph.org/flac/format.html */
|
|
|
|
/*@
|
|
@ requires file_recovery->data_check==&data_check_flac_metadata;
|
|
@ requires valid_data_check_param(buffer, buffer_size, file_recovery);
|
|
@ ensures valid_data_check_result(\result, file_recovery);
|
|
@ assigns file_recovery->calculated_file_size, file_recovery->data_check;
|
|
@*/
|
|
static data_check_t data_check_flac_metadata(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, file_recovery->data_check; */
|
|
while(file_recovery->calculated_file_size + buffer_size/2 >= file_recovery->file_size &&
|
|
file_recovery->calculated_file_size + 4 < 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 - 4; */
|
|
const uint32_t *p32=(const uint32_t *)&buffer[i];
|
|
const uint32_t size=be32(*p32)&0x00ffffff;
|
|
#ifdef DEBUG_FLAC
|
|
log_info("data_check_flac_metadata calculated_file_size=0x%llx: 0x%02x\n",
|
|
(long long unsigned)file_recovery->calculated_file_size, buffer[i]);
|
|
#endif
|
|
if((buffer[i]&0x7f)==0x7f)
|
|
return DC_ERROR;
|
|
file_recovery->calculated_file_size+=(uint64_t)4+size;
|
|
if((buffer[i]&0x80)==0x80)
|
|
{
|
|
file_recovery->data_check=NULL;
|
|
return DC_CONTINUE;
|
|
}
|
|
}
|
|
return DC_CONTINUE;
|
|
}
|
|
|
|
/*@
|
|
@ requires buffer_size >= 8;
|
|
@ requires separation: \separated(&file_hint_flac, 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_flac(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 uint32_t *p32=(const uint32_t *)&buffer[4];
|
|
const uint32_t size=be32(*p32)&0x00ffffff;
|
|
reset_file_recovery(file_recovery_new);
|
|
#ifdef DJGPP
|
|
file_recovery_new->extension="flc";
|
|
#else
|
|
file_recovery_new->extension=file_hint_flac.extension;
|
|
#endif
|
|
file_recovery_new->min_filesize=4+size;
|
|
if(file_recovery_new->blocksize >= 4)
|
|
{
|
|
file_recovery_new->calculated_file_size=4;
|
|
file_recovery_new->data_check=&data_check_flac_metadata;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static void register_header_check_flac(file_stat_t *file_stat)
|
|
{
|
|
/* Stream marker followed by STREAMINFO Metadata block */
|
|
static const unsigned char flac_header[5]= {'f', 'L', 'a', 'C', 0x00};
|
|
static const unsigned char flac_header2[5]= {'f', 'L', 'a', 'C', 0x80};
|
|
register_header_check(0, flac_header,sizeof(flac_header), &header_check_flac, file_stat);
|
|
#ifndef DISABLED_FOR_FRAMAC
|
|
register_header_check(0, flac_header2,sizeof(flac_header2), &header_check_flac, file_stat);
|
|
#endif
|
|
}
|
|
#endif
|