Difference between pages "Cell Phone Forensics" and "Google Chrome"

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(Example queries)
 
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== Guidelines ==
+
Google Chrome is a [[Web Browser|web browser]] developed by Google Inc.
  
# If on, switch it off. If off, leave off.  
+
== Configuration ==
 +
The Google Chrome configuration can be found in the '''Preferences''' file.
  
#* Note only under exceptional circumstances should the handset be left switched on and in any case every precaution to prevent the handset connecting with the Communication Service Provider should be made. Consider use of one of many [[wireless preservation]] or [[RF isolation]] techniques. Note that the slightest signal leakage will allow an overwriting text message through even if a phone call can't get through.
+
On Linux
 +
<pre>
 +
/home/$USER/.config/google-chrome/Default/Preferences
 +
</pre>
  
#* Instead of switching off, it may be better to remove the battery. Phones run a different part of their program when they are turned off.  You may wish to avoid having this part of the program run.
+
On MacOS-X
 +
<pre>
 +
/Users/$USER/Library/Application Support/Google/Chrome/Default/Preferences
 +
</pre>
  
#* Note that removing the battery or powering off a mobile phone may introduce a handset unlock code upon powering the device on.
+
On Windows XP
 +
<pre>
 +
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Preferences
 +
</pre>
  
# Collect and preserve other surrounding and related devices. Be especially careful to collect the power charger. The phone's battery will only last a certain amount of time. When it dies, much of the data on the device may go too!
+
On Windows Vista and later
+
<pre>
# Plug the phone in, preferably in the evidence room, as soon as possible.
+
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences
# Retain [[search warrant]] (if necessary - [[LE]]).
+
</pre>
# Return device to forensic lab if able.
+
# Use [[forensically sound]] tools for processing. However, also remember ACPO Principle 2 says: In exceptional circumstances, where a person finds it necessary to access original data held on a computer or on storage media, that person must be competent to do so and be able to give evidence explaining the relevance and the implications of their actions.
+
  
== Notes ==
+
Or for '''Chromium'''
  
Expand on as to what to collect:
+
On Linux
 +
<pre>
 +
/home/$USER/.config/chromium/Default/Preferences
 +
</pre>
  
* [[ESN]],
+
On MacOS-X
* [[IMEI]],
+
<pre>
* [[Carrier]],
+
/Users/$USER/Library/Application Support/Chromium/Default/Preferences
* Manufacturer,
+
</pre>
* Model Number,
+
* Color, and
+
* Other information related to [[Cell Phone]] and [[SIM Card]]...
+
  
Process:
+
On Windows XP
# Photograph the [[Cell Phone]] screen during power up.
+
<pre>
# Research the [[Cell Phone]] for technical specifications.
+
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Preferences
# Research the [[Cell Phone]] for forensic information.
+
</pre>
# Based on phone type [[GSM]], [[CDMA]], [[iDEN]], or [[Pay As You Go]] determine acquisition tools
+
  
GSM:
+
On Windows Vista and later
# Phone and SIM Card
+
<pre>
# SIM Card
+
C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Preferences
 +
</pre>
  
CDMA:
+
=== Plugins ===
# Phone
+
  
iDEN:
+
Information about plugins can be found under the "plugins section" of the Preferences file.
# Three major tools exist for iDEN Phones:
+
* iDEN Companion Pro
+
* iDEN Media Downloader
+
* iDEN Phonebook Manager
+
  
Pay As You Go:
+
=== DNS Prefetching ===
# Phone
+
  
== External Links ==
+
DNS is prefetched for related sites, e.g. links on the page.
 +
This behavior is controlled by the setting "Predict network actions to improve page load performance", which is enabled by default.
  
Articles and Reference Materials
+
If enabled the Preferences file contains:
*[http://www.e-evidence.info/cellarticles.html E-Evidence.Info Articles, Papers, Presentations, etc.]
+
<pre>
*[http://esm.cis.unisa.edu.au/new_esml/resources/publications/forensic%20analysis%20of%20mobile%20phones.pdf Forensic Analysis of Mobile Phones]
+
  "dns_prefetching": {
*[http://www.ijde.org/docs/03_spring_art1.pdf Forensics and the GSM Mobile Telephone System]
+
      "enabled": true,
*[http://www.cl.cam.ac.uk/~fms27/persec-2006/goodies/2006-Naccache-forensic.pdf Law Enforcement, Forensics and Mobile Communications]
+
</pre>
*[http://www.forensics.nl/mobile-pda-forensics Mobile Phone Forensics & PDA Forensics Links]
+
*[http://www.holmes.nl/MPF/FlowChartForensicMobilePhoneExamination.htm Netherlands Forensic Institute: Mobile Phone Forensics Examination - Basic Workflow and Preservation]
+
*[http://csrc.nist.gov/mobilesecurity/publications.html#MF U.S. National Institute of Standards and Technology Documents]
+
  
Conferences
+
If disabled the Preferences file contains:
*[http://www.MobileForensicsWorld.com/#Mobile Forensics World]
+
<pre>
 +
  "dns_prefetching": {
 +
      "enabled": false,
 +
</pre>
  
Investigative Support
+
== Start-up DNS queries ==
*[http://www.search.org/files/pdf/CellphoneInvestToolkit-0806.pdf Creating a Cell Phone Investigation Toolkit: Basic Hardware and Software Specifications]
+
*[http://www.e-evidence.info/cellular.html E-Evidence.Info Mobile Forensic Tools]
+
*[http://www.forensicfocus.com ForensicFocus.com(Practitioners Forum)]
+
*[http://www.hex-dump.com Hex-Dump.com(Advanced Forum for Hex Dump and Memory Analysis)]
+
*[http://www.Mobile-Examiner.com Mobile-Examiner.com (Forum for Practitioners)]
+
*[http://www.Mobile-Forensics.com Mobile-Forensics.com (Research Forum for Mobile Device Forensics)]
+
*[http://www.mfi-training.com Mobile Forensics Training Forum (Mobile Device Investigative Support and Training)]
+
*[http://www.SmartPhoneForensics.com SmartPhoneForensics.com (Mobile Device Forensics Training and Investigative Support)]
+
*[http://www.Phone-Forensics.com Phone-Forensics.com (Advanced Forum for Practitioners)]
+
*[http://trewmte.blogspot.com TREW Mobile Telephone Evidence (Mobile Telephone Evidence Practitioner Site)]
+
  
Phone Research
+
When Chrome starts it queries for several non-existing hostnames that consists of a 10 random characters, E.g.
*[http://www.GSMArena.com GSMArena.com (Technical information regarding GSM Cell Phones)]
+
<pre>
*[http://www.MobileForensicsCentral.com MobileForensicsCentral.com (Information regarding Cell Phone Forensic Applications)]
+
ttrgoiknff.mydomain.com
*[http://www.PhoneScoop.com PhoneScoop.com (Technical information regarding all Cell Phones)]
+
bxjhgftsyu.mydomain.com
*[http://www.ssddforensics.com/ Small Scale Digital Device Forensics Information]
+
yokjbjiagd.mydomain.com
 +
</pre>
 +
 
 +
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].
 +
 
 +
== Disk Cache ==
 +
The Google Chrome disk cache can be found in:
 +
 
 +
On Linux
 +
<pre>
 +
/home/$USER/.config/google-chrome/Default/Application Cache/Cache/
 +
</pre>
 +
 
 +
On MacOS-X
 +
<pre>
 +
/Users/$USER/Caches/Google/Chrome/Default/Cache/
 +
</pre>
 +
 
 +
On Windows XP
 +
<pre>
 +
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Cache\
 +
</pre>
 +
 
 +
On Windows Vista and later
 +
<pre>
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Cache\
 +
</pre>
 +
 
 +
The Chrome Cache contains different files with the following file names:
 +
* index
 +
* data_#; where # contains a decimal digit.
 +
* f_######; where # contains a hexadecimal digit.
 +
 
 +
For more info see Chrome developers site [http://www.chromium.org/developers/design-documents/network-stack/disk-cache].
 +
 
 +
== History ==
 +
Chrome stores the history of visited sites in a file named '''History'''. This file uses the [[SQLite database format]].
 +
 
 +
The '''History''' file can be found in same location as the '''Preferences''' file.
 +
 
 +
There is also '''Archived History''' that predates information in the '''History''' file.
 +
Note that the '''Archived History''' only contains visits.
 +
 
 +
=== Timestamps ===
 +
The '''History''' file uses the different timestamps.
 +
 
 +
==== visits.visit_time ====
 +
 
 +
The '''visits.visit_time''' is in (the number of) microseconds since January 1, 1601 UTC
 +
 
 +
Some Python code to do the conversion into human readable format:
 +
<pre>
 +
date_string = datetime.datetime( 1601, 1, 1 )
 +
            + datetime.timedelta( microseconds=timestamp )
 +
</pre>
 +
 
 +
Note that this timestamp is not the same as a Windows filetime which is (the number of) 100 nanoseconds since January 1, 1601 UTC
 +
 
 +
==== downloads.start_time ====
 +
 
 +
The '''downloads.start_time''' is in (the number of) seconds since January 1, 1970 UTC
 +
 
 +
Some Python code to do the conversion into human readable format:
 +
<pre>
 +
date_string = datetime.datetime( 1970, 1, 1 )
 +
            + datetime.timedelta( seconds=timestamp )
 +
</pre>
 +
 
 +
=== Example queries ===
 +
Some example queries:
 +
 
 +
To get an overview of the visited sites:
 +
<pre>
 +
SELECT datetime(((visits.visit_time/1000000)-11644473600), "unixepoch"), urls.url, urls.title FROM urls, visits WHERE urls.id = visits.url;
 +
</pre>
 +
 
 +
Note that the visit_time conversion looses precision.
 +
 
 +
To get an overview of the downloaded files:
 +
<pre>
 +
SELECT datetime(downloads.start_time, "unixepoch"), downloads.url, downloads.full_path, downloads.received_bytes, downloads.total_bytes FROM downloads;
 +
</pre>
 +
 
 +
How the information of the downloaded files is stored in the database can vary per version of Chrome a newer variant of the previous query is:
 +
<pre>
 +
SELECT datetime(((downloads.start_time/1000000)-11644473600), "unixepoch"), downloads.target_path, downloads_url_chains.url, downloads.received_bytes, downloads.total_bytes \
 +
FROM downloads, downloads_url_chains WHERE downloads.id = downloads_url_chains.id;
 +
</pre>
 +
 
 +
== See Also ==
 +
 
 +
* [[SQLite database format]]
 +
 
 +
== 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://computer-forensics.sans.org/blog/2010/01/21/google-chrome-forensics/ Google Chrome Forensics] by [[Kristinn Guðjónsson]]
 +
* [http://www.useragentstring.com/pages/Chrome/ Chrome User Agent strings]
 +
* [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
  
Training
+
[[Category:Applications]]
*[http://www.Mobile-Forensics.com Mobile-Forensics.com (Research Forum for Mobile Device Forensics)]
+
[[Category:Web Browsers]]
*[http://www.MobileForensicsWorld.com/Training.aspx#Mobile Forensics World Training]
+
*[http://www.mobileforensicstraining.com Mobile Forensics Training (Mobile Forensics Inc. Training Class site)]
+
*[http://www.paraben-training.com/training.html Paraben-Forensics.com (Paraben's Handheld Forensic Training Classes)]
+
*[http://www.SmartPhoneForensics.com SmartPhoneForensics.com (Mobile Device Forensics Training and Investigative Support)]
+

Revision as of 00:51, 20 April 2013

Google Chrome is a web browser developed by Google Inc.

Contents

Configuration

The Google Chrome configuration can be found in the Preferences file.

On Linux

/home/$USER/.config/google-chrome/Default/Preferences

On MacOS-X

/Users/$USER/Library/Application Support/Google/Chrome/Default/Preferences

On Windows XP

C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Preferences

On Windows Vista and later

C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences

Or for Chromium

On Linux

/home/$USER/.config/chromium/Default/Preferences

On MacOS-X

/Users/$USER/Library/Application Support/Chromium/Default/Preferences

On Windows XP

C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Preferences

On Windows Vista and later

C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Preferences

Plugins

Information about plugins can be found under the "plugins section" of the Preferences file.

DNS Prefetching

DNS is prefetched for related sites, e.g. links on the page. This behavior is controlled by the setting "Predict network actions to improve page load performance", which is enabled by default.

If enabled the Preferences file contains:

   "dns_prefetching": {
      "enabled": true,

If disabled the Preferences file contains:

   "dns_prefetching": {
      "enabled": false,

Start-up DNS queries

When Chrome starts it queries for several non-existing hostnames that consists of a 10 random characters, E.g.

ttrgoiknff.mydomain.com
bxjhgftsyu.mydomain.com
yokjbjiagd.mydomain.com

This is used to determine if your ISP is hijacking NXDOMAIN results [1].

Disk Cache

The Google Chrome disk cache can be found in:

On Linux

/home/$USER/.config/google-chrome/Default/Application Cache/Cache/

On MacOS-X

/Users/$USER/Caches/Google/Chrome/Default/Cache/

On Windows XP

C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Cache\

On Windows Vista and later

C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Cache\

The Chrome Cache contains different files with the following file names:

  • index
  • data_#; where # contains a decimal digit.
  • f_######; where # contains a hexadecimal digit.

For more info see Chrome developers site [2].

History

Chrome stores the history of visited sites in a file named History. This file uses the SQLite database format.

The History file can be found in same location as the Preferences file.

There is also Archived History that predates information in the History file. Note that the Archived History only contains visits.

Timestamps

The History file uses the different timestamps.

visits.visit_time

The visits.visit_time is in (the number of) microseconds since January 1, 1601 UTC

Some Python code to do the conversion into human readable format:

date_string = datetime.datetime( 1601, 1, 1 )
            + datetime.timedelta( microseconds=timestamp )

Note that this timestamp is not the same as a Windows filetime which is (the number of) 100 nanoseconds since January 1, 1601 UTC

downloads.start_time

The downloads.start_time is in (the number of) seconds since January 1, 1970 UTC

Some Python code to do the conversion into human readable format:

date_string = datetime.datetime( 1970, 1, 1 )
            + datetime.timedelta( seconds=timestamp )

Example queries

Some example queries:

To get an overview of the visited sites:

SELECT datetime(((visits.visit_time/1000000)-11644473600), "unixepoch"), urls.url, urls.title FROM urls, visits WHERE urls.id = visits.url;

Note that the visit_time conversion looses precision.

To get an overview of the downloaded files:

SELECT datetime(downloads.start_time, "unixepoch"), downloads.url, downloads.full_path, downloads.received_bytes, downloads.total_bytes FROM downloads;

How the information of the downloaded files is stored in the database can vary per version of Chrome a newer variant of the previous query is:

SELECT datetime(((downloads.start_time/1000000)-11644473600), "unixepoch"), downloads.target_path, downloads_url_chains.url, downloads.received_bytes, downloads.total_bytes \
FROM downloads, downloads_url_chains WHERE downloads.id = downloads_url_chains.id;

See Also

External Links