Google Chrome

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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

In browser way to control some settings:

chrome://extensions/
chrome://flags
chrome://settings

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 uses the Chrome Disk Cache Format and 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.

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;

Extensions

Chrome extensions are stored under user data directory in the extensions folder.

On Linux

/home/$USER/.config/google-chrome/Default/Extensions/
/home/$USER/.config/google-chrome-beta/Default/Extensions/
/home/$USER/.config/chromium/Default/Extensions/

On MacOS-X

/Users/$USER/Library/Application Support/Google/Chrome/Default/Extensions/
/Users/$USER/Library/Application Support/Chromium/Default/Extensions/
/Users/$USER/Library/Application Support/Google/Chrome Canary/Default/Extensions/

On Windows XP

C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Extensions\
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Extensions\
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome SxS\User Data\Default\Extensions\

On Windows Vista and later

C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Extensions\
C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Extensions\
C:\Users\%USERNAME%\AppData\Local\Google\Chrome SxS\User Data\Default\Extensions\

Extension Activity database

Chrome, presumably as of version 29 [3], stores exension activity in a file named Extension Activity. This file uses the SQLite database format.

It can be turned on by running:

./google-chrome --enable-extension-activity-logging

Query to get most of the relevant data:

SELECT datetime(((time/1000000)-11644473600), "unixepoch"), extension_id, action_type, api_name, args, page_url, page_title, arg_url, other, activity_id FROM activitylog_uncompressed;

The time span of the data tracked seems to be limited to a couple of days but can be useful in troubleshooting extension behavior.

Preferences File

From the Chromium site, 'Preferences are kept in a file named "Preferences", which every Chromium / Google Chrome user will have in their own user directory.'

On Linux

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

TODO confirm the following paths

On MacOS-X

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

On Windows XP

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

On Windows Vista and later

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

The file combines some settings from the policies, master_preferences, and local state.

This file contains several useful details about the extensions (under the "extensions" object):

  • "install_time": The timestamp of when the extension was installed in this Chrome profile.
  • "manifest": full extension manifest JSON
    • "key": the key associated with the extension (Used to determine the Extension ID)
  • "path": the Extension/ sub-path that the code is stored in under the profile

See Also

External Links

Tools

Open Source