diff options
| -rw-r--r-- | src/file_tar.c | 58 |
1 files changed, 39 insertions, 19 deletions
diff --git a/src/file_tar.c b/src/file_tar.c index 4d3a3567..7afc2449 100644 --- a/src/file_tar.c +++ b/src/file_tar.c @@ -3,17 +3,17 @@ File: file_tar.c Copyright (C) 1998-2005,2007 Christophe GRENIER <[email protected]> - + 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=®ister_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); } |