Difference between pages "Windows SuperFetch Format" and "Google Chrome"

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{{expand}}
+
Google Chrome is a [[Web Browser|web browser]] developed by Google Inc.
  
SuperFetch, is a memory management scheme that enhances the least-recently accessed approach with historical information and proactive memory management. [http://technet.microsoft.com/en-us/magazine/2007.03.vistakernel.aspx]
+
== Configuration ==
 +
The Google Chrome configuration can be found in the '''Preferences''' file.
  
<b>Note that the following format specification are incomplete.</b>
+
On Linux
 +
<pre>
 +
/home/$USER/.config/google-chrome/Default/Preferences
 +
</pre>
  
== SuperFetch DB files ==
+
On MacOS-X
The <tt>Ag*.db</tt> files are of the SuperFetch file format. E.g.
+
 
<pre>
 
<pre>
AgAppLaunch.db
+
/Users/$USER/Library/Application Support/Google/Chrome/Default/Preferences
AgCx_SC*.db
+
AgGlFaultHistory.db
+
AgGlFgAppHistory.db
+
AgGlGlobalHistory.db
+
AgGlUAD_%SID%.db
+
AgGlUAD_P_%SID%.db
+
AgRobust.db
+
 
</pre>
 
</pre>
  
The SuperFetch DB files can be stored in uncompressed or compressed form, where different version of Windows use different compressed forms:
+
On Windows XP
* Compressed SuperFetch DB - MEMO file format; Windows Vista
+
<pre>
* Compressed SuperFetch DB - MEM0 file format; Windows  7
+
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Preferences
* Compressed SuperFetch DB - MAM file format; Windows 8
+
</pre>
  
=== Compressed SuperFetch DB - MEMO file format ===
+
On Windows Vista and later
The MEM file consists of:
+
<pre>
* file header
+
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences
* compressed blocks
+
</pre>
  
This format uses the LZNT1 compression method
+
Or for '''Chrome SxS''' (Chrome side-by-side)
  
==== File header ====
+
<pre>
The file header is 84 bytes of size and consists of:
+
C:\Users\%USERNAME%\AppData\Local\Google\Chrome SxS\User Data\Default\Preferences
{| class="wikitable"
+
</pre>
|-
+
! Offset
+
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
| "MEMO" (0x4d, 0x45, 0x4d, 0x4f)
+
| Signature
+
|-
+
| 4
+
| 4
+
|
+
| Uncompressed (total) data size
+
|-
+
|}
+
  
==== Compressed blocks ====
+
Or for '''Chromium'''
The compressed block size is the chunk data size, which is part of the LZNT1 compressed data, + 2 bytes for the size of the chunk header itself.
+
  
The uncompressed block size is 4096 (0x1000) or the remaining uncompressed data size for the last block.
+
On Linux
 +
<pre>
 +
/home/$USER/.config/chromium/Default/Preferences
 +
</pre>
  
=== Compressed SuperFetch DB - MEM0 file format ===
+
On MacOS-X
The MEM file consists of:
+
<pre>
* file header
+
/Users/$USER/Library/Application Support/Chromium/Default/Preferences
* compressed blocks
+
</pre>
  
This format uses the LZXPRESS Huffman compression method
+
On Windows XP
 +
<pre>
 +
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Preferences
 +
</pre>
  
==== File header ====
+
On Windows Vista and later
The file header is 8 bytes of size and consists of:
+
<pre>
{| class="wikitable"
+
C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Preferences
|-
+
</pre>
! Offset
+
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
| "MEM0" (0x4d, 0x45, 0x4d, 0x30)
+
| Signature
+
|-
+
| 4
+
| 4
+
|
+
| Uncompressed (total) data size
+
|-
+
|}
+
  
==== Compressed blocks ====
+
=== Plugins ===
The file header is followed by compressed blocks:
+
{| class="wikitable"
+
|-
+
! Offset
+
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
|
+
| Compressed data size
+
|-
+
| 4
+
| ...
+
|
+
| Compressed data
+
|-
+
|}
+
  
The uncompressed block size is 65536 (0x10000) or the remaining uncompressed data size for the last block.
+
Information about plugins can be found under the "plugins section" of the Preferences file.
  
=== Compressed SuperFetch DB - MAM file format ===
+
=== DNS Prefetching ===
The MAM file consists of:
+
* file header
+
* compressed blocks
+
  
This format uses the LZXPRESS Huffman compression method.
+
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.
  
==== File header ====
+
If enabled the Preferences file contains:
The file header is 12 bytes of size and consists of:
+
<pre>
{| class="wikitable"
+
  "dns_prefetching": {
|-
+
      "enabled": true,
! Offset
+
</pre>
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
| "MAM\x84" (0x4d, 0x41, 0x4d, 0x84)
+
| Signature
+
|-
+
| 4
+
| 4
+
|
+
| Uncompressed (total) data size
+
|-
+
| 8
+
| 4
+
|
+
| Unknown (checksum?)
+
|-
+
|}
+
  
==== Compressed blocks ====
+
If disabled the Preferences file contains:
<b>TODO</b>
+
<pre>
 +
  "dns_prefetching": {
 +
      "enabled": false,
 +
</pre>
  
=== Uncompressed SuperFetch DB format ===
+
== Start-up DNS queries ==
<b>TODO</b>
+
  
==== File header ====
+
When Chrome starts it queries for several non-existing hostnames that consists of a 10 random characters, E.g.
<b>TODO</b>
+
<pre>
 +
ttrgoiknff.mydomain.com
 +
bxjhgftsyu.mydomain.com
 +
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].
  
{| class="wikitable"
+
== Disk Cache ==
|-
+
Google Chrome uses multiple caches, from [http://src.chromium.org/viewvc/chrome/trunk/src/net/base/cache_type.h?view=markup]:
! Offset
+
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
| 0x0000000e
+
| Unknown (Database type or signature?)
+
|-
+
| 4
+
| 4
+
|
+
| Uncompressed (total) data size
+
|-
+
|}
+
== TRX files ==
+
The <tt>Ag*.db.trx</tt> files are of the TRX file format. E.g.
+
 
<pre>
 
<pre>
AgCx_SC*.db.trx
+
// The types of caches that can be created.
 +
enum CacheType {
 +
    DISK_CACHE,  // Disk is used as the backing storage.
 +
    MEMORY_CACHE,  // Data is stored only in memory.
 +
    MEDIA_CACHE,  // Optimized to handle media files.
 +
    APP_CACHE,  // Backing store for an AppCache.
 +
    SHADER_CACHE, // Backing store for the GL shader cache.
 +
    PNACL_CACHE, // Backing store the PNaCl translation cache
 +
};
 
</pre>
 
</pre>
  
<b>Note that the following format specification is incomplete.</b>
+
<b>Note that $PROFILE (or %PROFILE%) the paths below is the profile dependent subdirectory which is normally Default but also could be Profile1, Profile2, etc.</b>
  
=== File header ===
+
The Google Chrome disk cache can be found in:
The file header is variable of size and consists of:
+
{| class="wikitable"
+
|-
+
! Offset
+
! Size
+
! Value
+
! Description
+
|-
+
| 0
+
| 4
+
| 1
+
| Unknown (Version?)
+
|-
+
| 4
+
| 4
+
|
+
| Unknown
+
|-
+
| 8
+
| 4
+
|
+
| File size
+
|-
+
| 12
+
| 4
+
|
+
| Maximum number of records (of the record offsets array)
+
|-
+
| 16
+
| 4
+
|
+
| Number of records
+
|-
+
| 20
+
| ...
+
|
+
| Record offsets array, where the record offset is a 32-bit integer. Unused record offset are set to 0.
+
|-
+
|}
+
  
=== Record ===
+
On Linux
<b>TODO describe</b>
+
 
 +
<pre>
 +
/home/$USER/.cache/chromium/$PROFILE/Cache/
 +
/home/$USER/.cache/google-chrome/$PROFILE/Cache/
 +
/home/$USER/.config/chromium/$PROFILE/Cache/
 +
/home/$USER/.config/google-chrome/$PROFILE/Cache/
 +
</pre>
 +
 
 +
<pre>
 +
/home/$USER/.cache/chromium/$PROFILE/Media Cache/
 +
/home/$USER/.cache/google-chrome/$PROFILE/Media Cache/
 +
/home/$USER/.config/chromium/$PROFILE/Media Cache/
 +
/home/$USER/.config/google-chrome/$PROFILE/Media Cache/
 +
</pre>
 +
 
 +
<pre>
 +
/home/$USER/.config/chromium/$PROFILE/Application Cache/Cache/
 +
/home/$USER/.config/google-chrome/$PROFILE/Application Cache/Cache/
 +
</pre>
 +
 
 +
<pre>
 +
/home/$USER/.config/chromium/$PROFILE/GPUCache/
 +
/home/$USER/.config/google-chrome/$PROFILE/GPUCache/
 +
</pre>
 +
 
 +
<pre>
 +
/home/$USER/.cache/chromium/PnaclTranslationCache/
 +
/home/$USER/.cache/google-chrome/PnaclTranslationCache/
 +
</pre>
 +
 
 +
On MacOS-X
 +
<pre>
 +
/Users/$USER/Library/Caches/Chromium/$PROFILE/Cache
 +
/Users/$USER/Library/Caches/Google/Chrome/$PROFILE/Cache
 +
</pre>
 +
 
 +
<b>TODO confirm the following paths</b>
 +
<pre>
 +
/Users/$USER/Caches/Chromium/$PROFILE/Cache/
 +
/Users/$USER/Caches/Google/Chrome/$PROFILE/Cache/
 +
</pre>
 +
 
 +
<pre>
 +
/Users/$USER/Library/Caches/Chromium/$PROFILE/Media Cache
 +
/Users/$USER/Library/Caches/Google/Chrome/$PROFILE/Media Cache
 +
</pre>
 +
 
 +
<pre>
 +
/Users/$USER/Library/Application Support/Chromium/$PROFILE/Application Cache/Cache/
 +
/Users/$USER/Library/Application Support/Google/Chrome/$PROFILE/Application Cache/Cache/
 +
</pre>
 +
 
 +
<pre>
 +
/Users/$USER/Library/Application Support/Chromium/$PROFILE/GPUCache/
 +
/Users/$USER/Library/Application Support/Google/Chrome/$PROFILE/GPUCache/
 +
</pre>
 +
 
 +
<pre>
 +
/Users/$USER/Library/Caches/Chromium/PnaclTranslationCache/
 +
/Users/$USER/Library/Caches/Google/Chrome/PnaclTranslationCache/
 +
</pre>
 +
 
 +
On Windows XP
 +
 
 +
<b>TODO confirm the following paths</b>
 +
<pre>
 +
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Cache\
 +
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\Chromium\%PROFILE%\Cache\
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Cache\
 +
</pre>
 +
 
 +
<pre>
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\Application Cache\Cache\
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Application Cache\Cache\
 +
</pre>
 +
 
 +
<pre>
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\Media Cache\
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Media Cache\
 +
</pre>
 +
 
 +
<pre>
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\GPUCache\
 +
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\GPUCache\
 +
</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 Disk Cache Format]].
 +
 
 +
== 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 as of version 26:
 +
<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>
 +
 
 +
== Cookies ==
 +
Chrome stores the cookies in a file named '''Cookies'''. This file uses the [[SQLite database format]].
 +
 
 +
=== Extension Cookies ===
 +
Chrome stores the cookies used by extensions in a file named '''Extension Cookies'''. This file uses the [[SQLite database format]].
 +
 
 +
<pre>
 +
SELECT datetime(((cookies.creation_utc/1000000)-11644473600), "unixepoch"), cookies.host_key, cookies.name, cookies.value, cookies.path, \
 +
datetime(((cookies.expires_utc/1000000)-11644473600), "unixepoch"), cookies.secure, cookies.httponly, datetime(((cookies.last_access_utc/1000000)-11644473600), "unixepoch"), \
 +
cookies.has_expires, cookies.persistent, cookies.priority FROM cookies;
 +
</pre>
  
 
== See Also ==
 
== See Also ==
* [[SuperFetch]]
+
 
 +
* [[SQLite database format]]
  
 
== External Links ==
 
== External Links ==
* [http://technet.microsoft.com/en-us/magazine/2007.03.vistakernel.aspx Inside the Windows Vista Kernel: Part 2], by [[Mark Russinovich]], March 2007
+
* [http://en.wikipedia.org/wiki/Google_Chrome Wikipedia article on Google Chrome]
* [http://blog.rewolf.pl/blog/?p=214 Windows SuperFetch file format – partial specification], by ReWolf, October 5, 2011
+
* [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:File Formats]]
+
[[Category:Applications]]
 +
[[Category:Web Browsers]]

Revision as of 04:42, 22 June 2014

Google Chrome is a web browser developed by Google Inc.

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 Chrome SxS (Chrome side-by-side)

C:\Users\%USERNAME%\AppData\Local\Google\Chrome SxS\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

Google Chrome uses multiple caches, from [2]:

// The types of caches that can be created.
enum CacheType {
    DISK_CACHE,  // Disk is used as the backing storage.
    MEMORY_CACHE,  // Data is stored only in memory.
    MEDIA_CACHE,  // Optimized to handle media files.
    APP_CACHE,  // Backing store for an AppCache.
    SHADER_CACHE, // Backing store for the GL shader cache.
    PNACL_CACHE, // Backing store the PNaCl translation cache
};

Note that $PROFILE (or %PROFILE%) the paths below is the profile dependent subdirectory which is normally Default but also could be Profile1, Profile2, etc.

The Google Chrome disk cache can be found in:

On Linux

/home/$USER/.cache/chromium/$PROFILE/Cache/
/home/$USER/.cache/google-chrome/$PROFILE/Cache/
/home/$USER/.config/chromium/$PROFILE/Cache/
/home/$USER/.config/google-chrome/$PROFILE/Cache/
/home/$USER/.cache/chromium/$PROFILE/Media Cache/
/home/$USER/.cache/google-chrome/$PROFILE/Media Cache/
/home/$USER/.config/chromium/$PROFILE/Media Cache/
/home/$USER/.config/google-chrome/$PROFILE/Media Cache/
/home/$USER/.config/chromium/$PROFILE/Application Cache/Cache/
/home/$USER/.config/google-chrome/$PROFILE/Application Cache/Cache/
/home/$USER/.config/chromium/$PROFILE/GPUCache/
/home/$USER/.config/google-chrome/$PROFILE/GPUCache/
/home/$USER/.cache/chromium/PnaclTranslationCache/
/home/$USER/.cache/google-chrome/PnaclTranslationCache/

On MacOS-X

/Users/$USER/Library/Caches/Chromium/$PROFILE/Cache
/Users/$USER/Library/Caches/Google/Chrome/$PROFILE/Cache

TODO confirm the following paths

/Users/$USER/Caches/Chromium/$PROFILE/Cache/
/Users/$USER/Caches/Google/Chrome/$PROFILE/Cache/
/Users/$USER/Library/Caches/Chromium/$PROFILE/Media Cache
/Users/$USER/Library/Caches/Google/Chrome/$PROFILE/Media Cache
/Users/$USER/Library/Application Support/Chromium/$PROFILE/Application Cache/Cache/
/Users/$USER/Library/Application Support/Google/Chrome/$PROFILE/Application Cache/Cache/
/Users/$USER/Library/Application Support/Chromium/$PROFILE/GPUCache/
/Users/$USER/Library/Application Support/Google/Chrome/$PROFILE/GPUCache/
/Users/$USER/Library/Caches/Chromium/PnaclTranslationCache/
/Users/$USER/Library/Caches/Google/Chrome/PnaclTranslationCache/

On Windows XP

TODO confirm the following paths

C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Cache\
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\Chromium\%PROFILE%\Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\Application Cache\Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Application Cache\Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\Media Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\Media Cache\
C:\Users\%USERNAME%\AppData\Local\Google\Chromium\%PROFILE%\GPUCache\
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\%PROFILE%\GPUCache\

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 Disk Cache Format.

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 as of version 26:

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;

Cookies

Chrome stores the cookies in a file named Cookies. This file uses the SQLite database format.

Extension Cookies

Chrome stores the cookies used by extensions in a file named Extension Cookies. This file uses the SQLite database format.

SELECT datetime(((cookies.creation_utc/1000000)-11644473600), "unixepoch"), cookies.host_key, cookies.name, cookies.value, cookies.path, \
datetime(((cookies.expires_utc/1000000)-11644473600), "unixepoch"), cookies.secure, cookies.httponly, datetime(((cookies.last_access_utc/1000000)-11644473600), "unixepoch"), \
cookies.has_expires, cookies.persistent, cookies.priority FROM cookies;

See Also

External Links

Tools

Open Source