PhotoRec: stricter check for tar

This commit is contained in:
Christophe Grenier 2015-06-12 18:53:22 +02:00
parent 6adba5a0d8
commit 0dd2adf2da

View file

@ -3,17 +3,17 @@
File: file_tar.c
Copyright (C) 1998-2005,2007 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.
@ -27,6 +27,7 @@
#include <string.h>
#endif
#include <stdio.h>
#include <ctype.h>
#include "types.h"
#include "filegen.h"
#include "file_tar.h"
@ -43,25 +44,44 @@ const file_hint_t file_hint_tar= {
.register_header_check=&register_header_check_tar
};
static const unsigned char tar_header_gnu[6] = { 'u','s','t','a','r',0x00};
static const unsigned char tar_header_posix[8] = { 'u','s','t','a','r',' ',' ',0x00};
static void register_header_check_tar(file_stat_t *file_stat)
{
register_header_check(0x101, tar_header_gnu,sizeof(tar_header_gnu), &header_check_tar, file_stat);
register_header_check(0x101, tar_header_posix,sizeof(tar_header_posix), &header_check_tar, file_stat);
}
struct posix_header
{ /* byte offset */
char name[100]; /* 0 */
char mode[8]; /* 100 */
char uid[8]; /* 108 */
char gid[8]; /* 116 */
char size[12]; /* 124 */
char mtime[12]; /* 136 */
char chksum[8]; /* 148 */
char typeflag; /* 156 */
char linkname[100]; /* 157 */
char magic[6]; /* 257 */
char version[2]; /* 263 */
char uname[32]; /* 265 */
char gname[32]; /* 297 */
char devmajor[8]; /* 329 */
char devminor[8]; /* 337 */
char prefix[155]; /* 345 */
/* 500 */
};
int header_check_tar(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 posix_header *h=(const struct posix_header *)buffer;
if(file_recovery->file_stat!=NULL && file_recovery->file_stat->file_hint==&file_hint_tar)
return 0;
if(memcmp(&buffer[0x101],tar_header_gnu,sizeof(tar_header_gnu))==0 ||
memcmp(&buffer[0x101],tar_header_posix,sizeof(tar_header_posix))==0)
{
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_tar.extension;
return 1;
}
return 0;
if(!isspace(h->chksum[0]) && !((unsigned) (h->chksum[0]) - '0' <= 7))
return 0;
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_tar.extension;
file_recovery_new->min_filesize=512;
return 1;
}
static void register_header_check_tar(file_stat_t *file_stat)
{
static const unsigned char tar_header_gnu[6] = { 'u','s','t','a','r',0x00};
static const unsigned char tar_header_posix[8] = { 'u','s','t','a','r',' ',' ',0x00};
register_header_check(0x101, tar_header_gnu,sizeof(tar_header_gnu), &header_check_tar, file_stat);
register_header_check(0x101, tar_header_posix,sizeof(tar_header_posix), &header_check_tar, file_stat);
}