Difference between pages "Windows Prefetch File Format" and "Libsmraw"

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(Section A)
 
 
Line 1: Line 1:
{{expand}}
+
{{Infobox_Software |
 +
  name = libsmraw |
 +
  maintainer = [[Joachim Metz]] |
 +
  os = [[Linux]], [[FreeBSD]], [[NetBSD]], [[OpenBSD]], [[Mac OS X]], [[Windows]] |
 +
  genre = {{Disk imaging}} |
 +
  license = {{LGPL}} |
 +
  website = [https://code.google.com/p/libsmraw/ code.google.com/p/libsmraw/] |
 +
}}
  
A Windows Prefetch file consists of one file header and multiple file sections with different content. Not all content has an obvious forensic value.
+
The '''libsmraw''' package contains a library and applications to read and write (split) RAW storage media bitstream copies.
 +
Libsmraw contains supports for multiple (split) RAW naming schemes.
  
As far as have been possible to ascertain, there is no public description of the format. The description below has been synthesised from examination
+
== History ==
of multiple prefetch files.
+
  
== Characteristics ==
+
Libsmraw was created by [[Joachim Metz]] in 2010, while working for [http://en.hoffmannbv.nl/ Hoffmann Investigations].
{| class="wikitable"
+
Libsmraw is a rewrite of earlier work for the proof-of-concept multi-threaded imager: GNOME Forensic Imager.
|-
+
| <b>Integers</b>
+
| stored in little-endian
+
|-
+
| <b>Strings</b>
+
| Stored as [http://en.wikipedia.org/wiki/UTF-16/UCS-2 UTF-16 little-endian] without a byte-order-mark (BOM).
+
|-
+
| <b>Timestamps</b>
+
| Stored as [http://msdn2.microsoft.com/en-us/library/ms724284.aspx Windows FILETIME] in UTC.
+
|-
+
|}
+
  
== File header ==
+
== Tools ==  
The file header is 84 bytes of size and consists of:
+
The '''libsmraw''' package contains the following tools:
{| class="wikitable"
+
* '''smrawmount''', which FUSE mounts (split) RAW image files.
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
| H1
+
| 0x0000
+
| 4
+
| DWORD
+
| Format version (see format version section below)
+
|-
+
| H2
+
| 0x0004
+
| 4
+
| DWORD
+
| Signature 'SCCA' (or in hexadecimal representation 0x53 0x43 0x43 0x4)
+
|-
+
| H3
+
| 0x0008
+
| 4
+
| DWORD?
+
| Unknown - Values observed: 0x0F - Windows XP, 0x11 - Windows 7, Windows 8.1
+
|-
+
| H4
+
| 0x000C
+
| 4
+
| DWORD
+
| Prefetch file size (or length) (sometimes referred to as End of File (EOF)).
+
|-
+
| H5
+
|0x0010
+
| 60
+
| USTR
+
| The name of the (original) executable as a Unicode (UTF-16 litte-endian string), up to 29 characters and terminated by an end-of-string character (U+0000). This name should correspond with the one in the prefetch file filename.
+
|-
+
| H6
+
|0x004C
+
|4
+
|DWORD
+
|The prefetch hash. This hash value should correspond with the one in the prefetch file filename.
+
|-
+
| H7
+
|0x0050
+
|4
+
|?
+
| Unknown (flags)? Values observed: 0 for almost all prefetch files (XP); 1 for NTOSBOOT-B00DFAAD.pf (XP)
+
|-
+
|}
+
  
It's worth noting that the name of a carved prefetch file can be restored using the information in field H5 and H6, and its size can be determined by field H4.
+
The '''libsmraw''' package also contains the following bindings:
 +
* '''pysmraw''', bindings for Python.
  
=== Format version ===
+
== Examples ==  
  
{| class="wikitable"
+
FUSE mounting a split RAW image (libsmraw 20110916 or later)
|-
+
<pre>
! Value
+
smrawmount image.raw.000 mount_point
! Windows version
+
</pre>
|-
+
| 17 (0x11)
+
| Windows XP, Windows 2003
+
|-
+
| 23 (0x17)
+
| Windows Vista, Windows 7
+
|-
+
| 26 (0x1a)
+
| Windows 8.1 (note this could be Windows 8 as well but has not been confirmed)
+
|-
+
|}
+
  
=== File information ===
+
Or:
The format of the file information is version dependent.
+
<pre>
 +
smrawmount image.raw.??? mount_point
 +
</pre>
  
Note that some other format specifications consider the file information part of the file header.
+
== Also See ==
 
+
[[Raw_Image_Format | RAW Image format]]
==== File information - version 17 ====
+
The file information – version 17 is 68 bytes of size and consists of:
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
|
+
| 0x0054
+
| 4
+
| DWORD
+
| The offset to section A. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0058
+
| 4
+
| DWORD
+
| The number of entries in section A.
+
|-
+
|
+
| 0x005C
+
| 4
+
| DWORD
+
| The offset to section B. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0060
+
| 4
+
| DWORD
+
| The number of entries in section B.
+
|-
+
|
+
| 0x0064
+
| 4
+
| DWORD
+
| The offset to section C. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0068
+
| 4
+
| DWORD
+
| Length of section C.
+
|-
+
|
+
| 0x006C
+
| 4
+
| DWORD
+
| Offset to section D. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0070
+
| 4
+
| DWORD
+
| The number of entries in section D.
+
|-
+
|
+
| 0x0074
+
| 4
+
| DWORD
+
| Length of section D.
+
|-
+
|
+
| 0x0078
+
| 8
+
| FILETIME
+
| Latest execution time (or run time) of executable (FILETIME)
+
|-
+
|
+
| 0x0080
+
| 16
+
| ?
+
| Unknown ? Possibly structured as 4 DWORD. Observed values: /0x00000000 0x00000000 0x00000000 0x00000000/, /0x47868c00 0x00000000 0x47860c00 0x00000000/ (don't exclude the possibility here that this is remnant data)
+
|-
+
|
+
| 0x0090
+
| 4
+
| DWORD
+
| Execution counter (or run count)
+
|-
+
|
+
| 0x0094
+
| 4
+
| DWORD?
+
| Unknown ? Observed values: 1, 2, 3, 4, 5, 6 (XP)
+
|-
+
|}
+
 
+
==== File information - version 23 ====
+
The file information – version 23 is 156 bytes of size and consists of:
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
|
+
| 0x0054
+
| 4
+
| DWORD
+
| The offset to section A. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0058
+
| 4
+
| DWORD
+
| The number of entries in section A.
+
|-
+
|
+
| 0x005C
+
| 4
+
| DWORD
+
| The offset to section B. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0060
+
| 4
+
| DWORD
+
| The number of entries in section B.
+
|-
+
|
+
| 0x0064
+
| 4
+
| DWORD
+
| The offset to section C. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0068
+
| 4
+
| DWORD
+
| Length of section C.
+
|-
+
|
+
| 0x006C
+
| 4
+
| DWORD
+
| Offset to section D. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0070
+
| 4
+
| DWORD
+
| The number of entries in section D.
+
|-
+
|
+
| 0x0074
+
| 4
+
| DWORD
+
| Length of section D.
+
|-
+
|
+
| <b>0x0078</b>
+
| <b>8</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|
+
| 0x0080
+
| 8
+
| FILETIME
+
| Latest execution time (or run time) of executable (FILETIME)
+
|-
+
|
+
| 0x0088
+
| 16
+
| ?
+
| Unknown
+
|-
+
|
+
| 0x0098
+
| 4
+
| DWORD
+
| Execution counter (or run count)
+
|-
+
|
+
| 0x009C
+
| 4
+
| DWORD?
+
| Unknown
+
|-
+
|
+
| <b>0x00A0</b>
+
| <b>80</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|}
+
 
+
==== File information - version 26 ====
+
The file information – version 23 is 224 bytes of size and consists of:
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
|
+
| 0x0054
+
| 4
+
| DWORD
+
| The offset to section A. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0058
+
| 4
+
| DWORD
+
| The number of entries in section A.
+
|-
+
|
+
| 0x005C
+
| 4
+
| DWORD
+
| The offset to section B. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0060
+
| 4
+
| DWORD
+
| The number of entries in section B.
+
|-
+
|
+
| 0x0064
+
| 4
+
| DWORD
+
| The offset to section C. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0068
+
| 4
+
| DWORD
+
| Length of section C.
+
|-
+
|
+
| 0x006C
+
| 4
+
| DWORD
+
| Offset to section D. The offset is relative from the start of the file.
+
|-
+
|
+
| 0x0070
+
| 4
+
| DWORD
+
| The number of entries in section D.
+
|-
+
|
+
| 0x0074
+
| 4
+
| DWORD
+
| Length of section D.
+
|-
+
|
+
| 0x0078
+
| 8
+
| ?
+
| Unknown
+
|-
+
|
+
| 0x0080
+
| 8
+
| FILETIME
+
| Latest execution time (or run time) of executable (FILETIME)
+
|-
+
|
+
| <b>0x0088</b>
+
| <b>7 x 8 = 56</b>
+
| <b>FILETIME</b>
+
| <b>Older (most recent) latest execution time (or run time) of executable (FILETIME)</b>
+
|-
+
|
+
| <b>0x00C0</b>
+
| <b>16</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|
+
| 0x00D0
+
| 4
+
| DWORD
+
| Execution counter (or run count)
+
|-
+
|
+
| <b>0x00D4</b>
+
| <b>4</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|
+
| <b>0x00D8</b>
+
| <b>4</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|
+
| <b>0x00DC</b>
+
| <b>88</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|}
+
 
+
== Section A ==
+
This section contains an array with 20 byte (version 17) or 32 byte (version 23 and 26) metrics entry records.
+
 
+
A metrics entry records conists of:
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
|
+
| 0
+
| 4
+
| DWORD
+
| Start time in ms
+
|-
+
|
+
| 4
+
| 4
+
| DWORD
+
| Duration in ms
+
|-
+
|
+
| 8
+
| 4
+
| DWORD
+
| Copy of duration in ms
+
|-
+
|
+
| 12
+
| 4
+
| DWORD
+
| Filename string offset <br> The offset is relative to the start of the filename string section
+
|-
+
|
+
| 16
+
| 4
+
| DWORD
+
| Filename string number of characters without end-of-string characters
+
|-
+
|
+
| 20
+
| 4
+
| DWORD
+
| Unknown flags
+
|-
+
|
+
| 24
+
| 4
+
| DWORD
+
| Unknown
+
|-
+
|
+
| 28
+
| 4
+
| DWORD
+
| Unknown
+
|}
+
 
+
== Section B ==
+
This section contains an array with 12 byte (version 17, 23 and 26) entry records.
+
 
+
The actual format and usage of these entry records is currently not known.
+
 
+
== Section C - Filename strings ==
+
This section contains filenames strings, it consists of an array of UTF-16 little-endian formatted strings with end-of-string characters (U+0000).
+
 
+
At the end of the section there seems to be alignment padding that can contain remnant values.
+
 
+
== Section D - Volumes information (block) ==
+
 
+
Section D contains one or more subsections, each subsection refers to directories on a volume.
+
 
+
If all the executables and libraries referenced in the C section are from one single disk volume, there will be only one section in the D section. If multiple volumes are referenced by section C, section D will contain multiple sections.  (A simple way to force this situation is to copy, say, NOTEPAD.EXE to a USB drive, and start it from that volume. The corresponding prefetch file will have one D header referring to, e.g. \DEVICE\HARDDISK1\DP(1)0-0+4 (the USB drive), and one to, e.g. \DEVICE\HARDDISKVOLUME1\ (where the .DLLs and other support files were found).
+
 
+
In this section, all offsets are assumed to be counted from the start of the D section.
+
 
+
=== Volume information ===
+
The structure of the volume information is version dependent.
+
 
+
==== Volume information - version 17 ====
+
The volume information – version 17 is 40 bytes in size and consists of:
+
 
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
| VI1
+
| +0x0000
+
| 4
+
| DWORD
+
| Offset to volume device path (Unicode, terminated by U+0000)
+
|-
+
| VI2
+
| +0x0004
+
| 4
+
| DWORD
+
| Length of volume device path (nr of characters, including terminating U+0000)
+
|-
+
| VI3
+
| +0x0008
+
| 8
+
| FILETIME
+
| Volume creation time.
+
|-
+
| VI4
+
| +0x0010
+
| 4
+
| DWORD
+
| Volume serial number of volume indicated by volume string
+
|-
+
| VI5
+
| +0x0014
+
| 4
+
| DWORD
+
| Offset to sub section E
+
|-
+
| VI6
+
| +0x0018
+
| 4
+
| DWORD
+
| Length of sub section E (in bytes)
+
|-
+
| VI7
+
| +0x001C
+
| 4
+
| DWORD
+
| Offset to sub section F
+
|-
+
| VI8
+
| +0x0020
+
| 4
+
| DWORD
+
| Number of strings in sub section F
+
|-
+
| VI9
+
| +0x0024
+
| 4
+
| ?
+
| Unknown
+
|-
+
|}
+
 
+
==== Volume information - version 23 ====
+
The volume information entry – version 23 is 104 bytes in size and consists of:
+
 
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
| VI1
+
| +0x0000
+
| 4
+
| DWORD
+
| Offset to volume device path (Unicode, terminated by U+0000)
+
|-
+
| VI2
+
| +0x0004
+
| 4
+
| DWORD
+
| Length of volume device path (nr of characters, including terminating U+0000)
+
|-
+
| VI3
+
| +0x0008
+
| 8
+
| FILETIME
+
| Volume creation time.
+
|-
+
| VI4
+
| +0x0010
+
| 4
+
| DWORD
+
| Volume serial number of volume indicated by volume string
+
|-
+
| VI5
+
| +0x0014
+
| 4
+
| DWORD
+
| Offset to sub section E
+
|-
+
| VI6
+
| +0x0018
+
| 4
+
| DWORD
+
| Length of sub section E (in bytes)
+
|-
+
| VI7
+
| +0x001C
+
| 4
+
| DWORD
+
| Offset to sub section F
+
|-
+
| VI8
+
| +0x0020
+
| 4
+
| DWORD
+
| Number of strings in sub section F
+
|-
+
| VI9
+
| +0x0024
+
| 4
+
| ?
+
| Unknown
+
|-
+
| <b>VI10</b>
+
| <b>+0x0028</b>
+
| <b>28</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
| <b>VI11</b>
+
| <b>+0x0044</b>
+
| <b>4</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
| <b>VI12</b>
+
| <b>+0x0048</b>
+
| <b>28</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
| <b>VI13</b>
+
| <b>+0x0064</b>
+
| <b>4</b>
+
| <b>?</b>
+
| <b>Unknown</b>
+
|-
+
|}
+
 
+
==== Volume information - version 26 ====
+
The volume information entry – version 26 appears to be similar to volume information – version 23.
+
 
+
=== Sub section E - NTFS file references ===
+
This sub section can contain NTFS file references.
+
 
+
For more information see [https://googledrive.com/host/0B3fBvzttpiiSbl9XZGZzQ05hZkU/Windows%20Prefetch%20File%20(PF)%20format.pdf Windows Prefetch File (PF) format].
+
 
+
=== Sub section F - Directory strings ===
+
This sub sections contains directory strings. The number of strings is stored in the volume information.
+
 
+
A directory string is stored in the following structure:
+
{| class="wikitable"
+
|-
+
! Field
+
! Offset
+
! Length
+
! Type
+
! Notes
+
|-
+
|
+
| 0x0000
+
| 2
+
| DWORD
+
| Number of characters (WORDs) of the directory name. The value does not include the end-of-string character.
+
|-
+
|
+
| 0x0002
+
|
+
| USTR
+
| The directory name as a Unicode (UTF-16 litte-endian string) terminated by an end-of-string character (U+0000).
+
|-
+
|}
+
 
+
== See Also ==
+
* [[Prefetch]]
+
  
 
== External Links ==
 
== External Links ==
* [https://googledrive.com/host/0B3fBvzttpiiSbl9XZGZzQ05hZkU/Windows%20Prefetch%20File%20(PF)%20format.pdf Windows Prefetch File (PF) format], by the [[libssca|libssca project]]
 
* [http://bitbucket.cassidiancybersecurity.com/prefetch-parser/wiki/Home Windows Prefetch file format], by the [http://bitbucket.cassidiancybersecurity.com/prefetch-parser prefetch-parser] project.
 
  
[[Category:File Formats]]
+
* [https://code.google.com/p/libsmraw/ Project site]

Revision as of 08:45, 21 June 2014

libsmraw
Maintainer: Joachim Metz
OS: Linux, FreeBSD, NetBSD, OpenBSD, Mac OS X, Windows
Genre: Disk imaging
License: LGPL
Website: code.google.com/p/libsmraw/

The libsmraw package contains a library and applications to read and write (split) RAW storage media bitstream copies. Libsmraw contains supports for multiple (split) RAW naming schemes.

History

Libsmraw was created by Joachim Metz in 2010, while working for Hoffmann Investigations. Libsmraw is a rewrite of earlier work for the proof-of-concept multi-threaded imager: GNOME Forensic Imager.

Tools

The libsmraw package contains the following tools:

  • smrawmount, which FUSE mounts (split) RAW image files.

The libsmraw package also contains the following bindings:

  • pysmraw, bindings for Python.

Examples

FUSE mounting a split RAW image (libsmraw 20110916 or later)

smrawmount image.raw.000 mount_point

Or:

smrawmount image.raw.??? mount_point

Also See

RAW Image format

External Links