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/*
File: file_7z.c
Copyright (C) 2005-2007 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_7z)
#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_7z(file_stat_t *file_stat);
const file_hint_t file_hint_7z= {
.extension="7z",
.description="7zip archive file",
.max_filesize=PHOTOREC_MAX_FILE_SIZE,
.recover=1,
.enable_by_default=1,
.register_header_check=®ister_header_check_7z
};
struct header_7z {
unsigned char signature[6];
uint8_t majorversion;
uint8_t minorversion;
uint32_t crcFromArchive;
uint64_t nextHeaderOffset;
uint64_t nextHeaderSize;
uint64_t nextHeaderCRC;
} __attribute__ ((gcc_struct, __packed__));
/*@
@ requires buffer_size >= sizeof(struct header_7z);
@ requires separation: \separated(&file_hint_7z, 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_7z(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 header_7z *buffer_7z=(const struct header_7z *)buffer;
if(buffer_7z->majorversion!=0 ||
le64(buffer_7z->nextHeaderSize)==0)
return 0;
if( le64(buffer_7z->nextHeaderOffset) > 0x7000000000000000 ||
le64(buffer_7z->nextHeaderSize) > 0x7000000000000000)
return 0;
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_7z.extension;
file_recovery_new->min_filesize=31;
/* Signature size 12 + Start header size 20 */
file_recovery_new->calculated_file_size=(uint64_t)le64(buffer_7z->nextHeaderOffset)+
le64(buffer_7z->nextHeaderSize) + 12 + 20;
file_recovery_new->data_check=&data_check_size;
file_recovery_new->file_check=&file_check_size;
return 1;
}
static void register_header_check_7z(file_stat_t *file_stat)
{
static const unsigned char header_7z[6] = {'7','z', 0xbc, 0xaf, 0x27, 0x1c};
register_header_check(0, header_7z, sizeof(header_7z), &header_check_7z, file_stat);
}
#endif
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