From 73c578af594d2de410bf5c255891e110e9fb42c3 Mon Sep 17 00:00:00 2001 From: Christophe Grenier Date: Mon, 28 Dec 2009 08:02:25 +0100 Subject: [PATCH] PhotoRec: recover ext[234] filesystem file image --- src/Makefile.am | 1 + src/file_ext2.c | 87 +++++++++++++++++++++++++++++++++++++++++++++++++ src/file_list.c | 2 ++ 3 files changed, 90 insertions(+) create mode 100644 src/file_ext2.c diff --git a/src/Makefile.am b/src/Makefile.am index 596ef7c8..16737bd1 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -87,6 +87,7 @@ file_C = filegen.c \ file_evt.c \ file_exe.c \ file_ext.c \ + file_ext2.c \ file_fat.c \ file_fbk.c \ file_fcp.c \ diff --git a/src/file_ext2.c b/src/file_ext2.c new file mode 100644 index 00000000..46a16d76 --- /dev/null +++ b/src/file_ext2.c @@ -0,0 +1,87 @@ +/* + + File: file_ext2_fs.c + + Copyright (C) 1998-2005,2007 Christophe GRENIER + + 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. + + */ + +#ifdef HAVE_CONFIG_H +#include +#endif +#ifdef HAVE_STRING_H +#include +#endif +#include +#include "types.h" +#include "common.h" +#include "ext2.h" +#include "filegen.h" + +static void register_header_check_ext2_fs(file_stat_t *file_stat); +static int header_check_ext2_fs(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 file_hint_t file_hint_ext2_fs= { + .extension="ext", + .description="ext2/ext3/ext4 Filesystem", + .min_header_distance=0, + .max_filesize=0, + .recover=1, + .enable_by_default=0, + .register_header_check=®ister_header_check_ext2_fs +}; + +static const unsigned char ext2_fs_header[2]= {0x53, 0xEF}; + +static void register_header_check_ext2_fs(file_stat_t *file_stat) +{ + register_header_check(0x438, ext2_fs_header,sizeof(ext2_fs_header), &header_check_ext2_fs, file_stat); +} + +static int header_check_ext2_fs(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 ext2_super_block *sb=(const struct ext2_super_block *)&buffer[0x400]; + if(le16(sb->s_magic)!=EXT2_SUPER_MAGIC) + return 0; + if (le32(sb->s_free_blocks_count) >= le32(sb->s_blocks_count)) + return 0; + if (le32(sb->s_free_inodes_count) >= le32(sb->s_inodes_count)) + return 0; + if (le16(sb->s_errors)!=0 && + (le16(sb->s_errors) != EXT2_ERRORS_CONTINUE) && + (le16(sb->s_errors) != EXT2_ERRORS_RO) && + (le16(sb->s_errors) != EXT2_ERRORS_PANIC)) + return 0; + if ((le16(sb->s_state) & ~(EXT2_VALID_FS | EXT2_ERROR_FS))!=0) + return 0; + if (le32(sb->s_blocks_count) == 0) /* reject empty filesystem */ + return 0; + if(le32(sb->s_log_block_size)>2) /* block size max = 4096, can be 8192 on alpha */ + return 0; + if(le16(sb->s_block_group_nr)!=0) + return 0; + if(file_recovery!=NULL && file_recovery->file_stat!=NULL && + file_recovery->file_stat->file_hint==&file_hint_ext2_fs && + file_recovery->calculated_file_size==(uint64_t)le32(sb->s_blocks_count)*(EXT2_MIN_BLOCK_SIZE<s_log_block_size))) + return 0; + reset_file_recovery(file_recovery_new); + file_recovery_new->extension=file_hint_ext2_fs.extension; + file_recovery_new->calculated_file_size=(uint64_t)le32(sb->s_blocks_count)*(EXT2_MIN_BLOCK_SIZE<s_log_block_size)); + file_recovery_new->data_check=&data_check_size; + file_recovery_new->file_check=&file_check_size; + return 1; +} diff --git a/src/file_list.c b/src/file_list.c index 64d4e67b..aea70ed3 100644 --- a/src/file_list.c +++ b/src/file_list.c @@ -89,6 +89,7 @@ extern const file_hint_t file_hint_emf; extern const file_hint_t file_hint_evt; extern const file_hint_t file_hint_exe; extern const file_hint_t file_hint_ext2_sb; +extern const file_hint_t file_hint_ext2_fs; extern const file_hint_t file_hint_fat; extern const file_hint_t file_hint_fbk; extern const file_hint_t file_hint_fcp; @@ -286,6 +287,7 @@ file_enable_t list_file_enable[]= { .enable=0, .file_hint=&file_hint_evt }, { .enable=0, .file_hint=&file_hint_exe }, { .enable=0, .file_hint=&file_hint_ext2_sb }, + { .enable=0, .file_hint=&file_hint_ext2_fs }, { .enable=0, .file_hint=&file_hint_fat }, { .enable=0, .file_hint=&file_hint_fbk }, { .enable=0, .file_hint=&file_hint_fcp },