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 File: file_tar.c
Copyright (C) 1998-2005,2007 Christophe GRENIER <grenier@cgsecurity.org> Copyright (C) 1998-2005,2007 Christophe GRENIER <grenier@cgsecurity.org>
This software is free software; you can redistribute it and/or modify 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 it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or the Free Software Foundation; either version 2 of the License, or
(at your option) any later version. (at your option) any later version.
This program is distributed in the hope that it will be useful, This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details. GNU General Public License for more details.
You should have received a copy of the GNU General Public License along 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 with this program; if not, write the Free Software Foundation, Inc., 51
Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
@ -27,6 +27,7 @@
#include <string.h> #include <string.h>
#endif #endif
#include <stdio.h> #include <stdio.h>
#include <ctype.h>
#include "types.h" #include "types.h"
#include "filegen.h" #include "filegen.h"
#include "file_tar.h" #include "file_tar.h"
@ -43,25 +44,44 @@ const file_hint_t file_hint_tar= {
.register_header_check=&register_header_check_tar .register_header_check=&register_header_check_tar
}; };
static const unsigned char tar_header_gnu[6] = { 'u','s','t','a','r',0x00}; struct posix_header
static const unsigned char tar_header_posix[8] = { 'u','s','t','a','r',' ',' ',0x00}; { /* byte offset */
char name[100]; /* 0 */
static void register_header_check_tar(file_stat_t *file_stat) char mode[8]; /* 100 */
{ char uid[8]; /* 108 */
register_header_check(0x101, tar_header_gnu,sizeof(tar_header_gnu), &header_check_tar, file_stat); char gid[8]; /* 116 */
register_header_check(0x101, tar_header_posix,sizeof(tar_header_posix), &header_check_tar, file_stat); 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) 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) if(file_recovery->file_stat!=NULL && file_recovery->file_stat->file_hint==&file_hint_tar)
return 0; return 0;
if(memcmp(&buffer[0x101],tar_header_gnu,sizeof(tar_header_gnu))==0 || if(!isspace(h->chksum[0]) && !((unsigned) (h->chksum[0]) - '0' <= 7))
memcmp(&buffer[0x101],tar_header_posix,sizeof(tar_header_posix))==0) return 0;
{ reset_file_recovery(file_recovery_new);
reset_file_recovery(file_recovery_new); file_recovery_new->extension=file_hint_tar.extension;
file_recovery_new->extension=file_hint_tar.extension; file_recovery_new->min_filesize=512;
return 1; return 1;
} }
return 0;
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);
} }