Difference between pages "Google Chrome" and "Libsmraw"

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(Disk Cache)
 
(Tools)
 
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Google Chrome is a [[Web Browser|web browser]] developed by Google Inc.
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{{Infobox_Software |
 +
  name = libsmraw |
 +
  maintainer = [[Joachim Metz]] |
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  os = [[Linux]], [[FreeBSD]], [[NetBSD]], [[OpenBSD]], [[Mac OS X]], [[Windows]] |
 +
  genre = {{Disk imaging}} |
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  license = {{LGPL}} |
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  website = [https://code.google.com/p/libsmraw/ code.google.com/p/libsmraw/] |
 +
}}
  
== Configuration ==
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The '''libsmraw''' package contains a library and applications to read and write (split) RAW storage media bitstream copies.
The Google Chrome configuration can be found in the '''Preferences''' file.
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Libsmraw contains supports for multiple (split) RAW naming schemes.
  
On Linux
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== History ==
<pre>
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/home/$USER/.config/google-chrome/Default/Preferences
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</pre>
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On MacOS-X
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Libsmraw was created by [[Joachim Metz]] in 2010, while working for [http://en.hoffmannbv.nl/ Hoffmann Investigations].
<pre>
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Libsmraw is a rewrite of earlier work for the proof-of-concept multi-threaded imager: GNOME Forensic Imager.
/Users/$USER/Library/Application Support/Google/Chrome/Default/Preferences
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</pre>
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On Windows XP
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== Tools ==
<pre>
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The '''libsmraw''' package contains the following tools:
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Preferences
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* '''smrawmount''', which FUSE mounts (split) RAW image files.
</pre>
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On Windows Vista and later
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The '''libsmraw''' package also contains the following bindings:
<pre>
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* '''pysmraw''', bindings for Python (libsmraw 20140621 or later).
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences
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</pre>
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Or for '''Chromium'''
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== Examples ==
  
On Linux
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FUSE mounting a split RAW image (libsmraw 20110916 or later)
 
<pre>
 
<pre>
/home/$USER/.config/chromium/Default/Preferences
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smrawmount image.raw.000 mount_point
 
</pre>
 
</pre>
  
On MacOS-X
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Or:
 
<pre>
 
<pre>
/Users/$USER/Library/Application Support/Chromium/Default/Preferences
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smrawmount image.raw.??? mount_point
 
</pre>
 
</pre>
  
On Windows XP
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== Also See ==
<pre>
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[[Raw_Image_Format | RAW Image format]]
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Preferences
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</pre>
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On Windows Vista and later
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<pre>
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C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Preferences
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</pre>
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=== Plugins ===
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Information about plugins can be found under the "plugins section" of the Preferences file.
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=== DNS Prefetching ===
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DNS is prefetched for related sites, e.g. links on the page.
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This behavior is controlled by the setting "Predict network actions to improve page load performance", which is enabled by default.
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If enabled the Preferences file contains:
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<pre>
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  "dns_prefetching": {
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      "enabled": true,
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</pre>
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If disabled the Preferences file contains:
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<pre>
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  "dns_prefetching": {
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      "enabled": false,
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</pre>
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== Start-up DNS queries ==
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When Chrome starts it queries for several non-existing hostnames that consists of a 10 random characters, E.g.
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<pre>
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ttrgoiknff.mydomain.com
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bxjhgftsyu.mydomain.com
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yokjbjiagd.mydomain.com
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</pre>
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This is used to determine if your ISP is hijacking NXDOMAIN results [http://www.google.com/support/forum/p/Chrome/thread?tid=3511015c72a7b314&hl=en].
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== Disk Cache ==
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Google Chrome uses multiple caches, from [http://src.chromium.org/viewvc/chrome/trunk/src/net/base/cache_type.h?view=markup]:
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<pre>
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// The types of caches that can be created.
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enum CacheType {
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    DISK_CACHE,  // Disk is used as the backing storage.
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    MEMORY_CACHE,  // Data is stored only in memory.
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    MEDIA_CACHE,  // Optimized to handle media files.
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    APP_CACHE,  // Backing store for an AppCache.
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    SHADER_CACHE, // Backing store for the GL shader cache.
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    PNACL_CACHE, // Backing store the PNaCl translation cache
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};
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</pre>
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The Google Chrome disk cache can be found in:
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On Linux
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<pre>
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/home/$USER/.cache/google-chrome/Default/Cache/
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</pre>
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<pre>
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/home/$USER/.cache/google-chrome/Default/Media Cache/
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</pre>
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<pre>
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/home/$USER/.config/google-chrome/Default/Application Cache/Cache/
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</pre>
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<pre>
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/home/$USER/.config/google-chrome/Default/Cache/
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</pre>
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On MacOS-X
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<pre>
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/Users/$USER/Caches/Google/Chrome/Default/Cache/
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</pre>
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On Windows XP
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<pre>
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C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Cache\
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</pre>
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On Windows Vista and later
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<pre>
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C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Cache\
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</pre>
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The Chrome Cache contains different files with the following file names:
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* index
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* data_#; where # contains a decimal digit.
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* f_######; where # contains a hexadecimal digit.
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For more info see Chrome developers site [http://www.chromium.org/developers/design-documents/network-stack/disk-cache].
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== History ==
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Chrome stores the history of visited sites in a file named '''History'''. This file uses the [[SQLite database format]].
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The '''History''' file can be found in same location as the '''Preferences''' file.
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There is also '''Archived History''' that predates information in the '''History''' file.
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Note that the '''Archived History''' only contains visits.
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=== Timestamps ===
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The '''History''' file uses the different timestamps.
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==== visits.visit_time ====
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The '''visits.visit_time''' is in (the number of) microseconds since January 1, 1601 UTC
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Some Python code to do the conversion into human readable format:
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<pre>
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date_string = datetime.datetime( 1601, 1, 1 )
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            + datetime.timedelta( microseconds=timestamp )
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</pre>
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Note that this timestamp is not the same as a Windows filetime which is (the number of) 100 nanoseconds since January 1, 1601 UTC
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==== downloads.start_time ====
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The '''downloads.start_time''' is in (the number of) seconds since January 1, 1970 UTC
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Some Python code to do the conversion into human readable format:
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<pre>
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date_string = datetime.datetime( 1970, 1, 1 )
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            + datetime.timedelta( seconds=timestamp )
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</pre>
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=== Example queries ===
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Some example queries:
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To get an overview of the visited sites:
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<pre>
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SELECT datetime(((visits.visit_time/1000000)-11644473600), "unixepoch"), urls.url, urls.title FROM urls, visits WHERE urls.id = visits.url;
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</pre>
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Note that the visit_time conversion looses precision.
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To get an overview of the downloaded files:
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<pre>
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SELECT datetime(downloads.start_time, "unixepoch"), downloads.url, downloads.full_path, downloads.received_bytes, downloads.total_bytes FROM downloads;
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</pre>
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How the information of the downloaded files is stored in the database can vary per version of Chrome as of version 26:
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<pre>
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SELECT datetime(((downloads.start_time/1000000)-11644473600), "unixepoch"), downloads.target_path, downloads_url_chains.url, downloads.received_bytes, downloads.total_bytes \
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FROM downloads, downloads_url_chains WHERE downloads.id = downloads_url_chains.id;
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</pre>
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== See Also ==
+
 
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* [[SQLite database format]]
+
  
 
== External Links ==
 
== External Links ==
* [http://en.wikipedia.org/wiki/Google_Chrome Wikipedia article on Google Chrome]
 
* [http://www.chromium.org/user-experience/user-data-directory The Chromium Projects - User Data Directory]
 
* [http://www.chromium.org/developers/design-documents/network-stack/disk-cache Chrome Disk Cache]
 
* [http://www.google.com/support/forum/p/Chrome/thread?tid=3511015c72a7b314&hl=en Chrome support forum article random 10 character hostnames on startup]
 
* [http://www.useragentstring.com/pages/Chrome/ Chrome User Agent strings]
 
* [http://computer-forensics.sans.org/blog/2010/01/21/google-chrome-forensics/ Google Chrome Forensics] by [[Kristinn Guðjónsson]], January 21, 2010
 
* [http://linuxsleuthing.blogspot.ch/2013/02/cashing-in-on-google-chrome-cache.html?m=1 Cashing in on the Google Chrome Cache], [[John Lehr]], February 24, 2013
 
* [http://www.obsidianforensics.com/blog/history-index-files-removed-from-chrome/ History Index files removed from Chrome v30], by Ryan Benson, October 2, 2013
 
* [https://hindsight-internet-history.googlecode.com/files/Evolution_of_Chrome_Databases.png Evolution of Chrome Databases], by Ryan Benson, November 12, 2013
 
 
== Tools ==
 
=== Open Source ===
 
* [https://code.google.com/p/hindsight-internet-history/ hindsight-internet-history]
 
  
[[Category:Applications]]
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* [https://code.google.com/p/libsmraw/ Project site]
[[Category:Web Browsers]]
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Latest revision as of 08:46, 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 (libsmraw 20140621 or later).

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