PLIST Files
The Macintosh operating system, version 10, is rich with
files called “property list files” or “p” list files if you
pronounce them aloud. A Windows user/adminstrator/examiner
will frequently ask where the registry is on a Mac. The
answer is, the Macintosh does not have a registry. There is
no central location that can be equated to the Microsoft
designed registry. With Mac OS X, the property list file has
been used for application settings, user preferences,
security settings, and many, many other uses.
Sponsored Advertisement
A property list file is an XML file. It might be in plain
text and simply read by your favorite text editor. It is also
possible that the property list file is a binary property
list file and you will not be able to read it directly unless
you use an application such as Apple’s free Property List
Editor.
There is always the Terminal command called plutil and is
used like this:
plutil -convert xml1 /path/to/file.plist
where the path is the file you wish to view. The output of
this command is text to your screen with the contents of the
file.
Property List Editor is available free thru
Apple’s Develop website as a part of
their Developer Tools. You
need this on
your forensic examination Macintosh!
Below is an example of the property list file
/Library/Preferences/com.apple.loginwindow.plist. We will
explore it in 3 forms.
com.apple.loginwindow.plist in binary form
First, we have the com.apple.loginwindow.plist in its native
form, binary (seen above). Apple has this property list file
encoded in binary format and this is what you will see when
attempting to look at it with any text viewer, such as the
‘more’ command in Terminal as seen here. If you are using
Encase, FTK, X-Ways, or similar Windows based forensic
products, expect the same output when you click on these
files.
(We have finally found a PLIST editor for Windows
here.)
com.apple.loginwindow.plist in XML form
Second, we have the same file decoded to its XML form. This
is easily read by any text viewer. A property list file that
has been binary encoded can be easily decoded to its XML form
by using the Terminal command “plutil”. But, as we can see
from our third example, there is little need to go thru that
Terminal typing challenge.
com.apple.loginwindow.plist in Property List
Editor
The above example shows how the same file is neatly decoded
and interpreted by the Apple application Property List
Editor. Not only is this easier on the eyes, it makes for
much nicer reporting. Property List Editor is terrible for
printing to PDF files unfortunately, but it allows you to
make window captures (as seen here) or you can export the
data to an application that can read the XML file if you need
to do something further with it. Typically, a window capture
will suffice.
Now that we understand how to read the data, we need to know
where to find it. The web page
Initial Data
Gathering mentioned several property list files that
contain excellent data that will likely make its way
into many of your cases, but that is just the start.
There are 4 “Library” folders in which the operating system
can access during operation. They are:
- /Users/username/Library
- /Library
- /Network/Library
- /System/Library
Each of these Library folders contain folders such as
“Preferences” which are a gold mine for property list files.
Don’t stop here though. Folders that don’t typically display
in the Finder such as:
- /private/etc
- /private/var
These folders have a huge directory structure that contain a
wealth of files, some of which are property list files.
So, now that we have made the entire hard drive and network
fair game for property list files, let’s end this end on a
good note and focus on the data that we need. Mac OS X is a
very organized operating system. When you are looking for
data that represents settings for a particular user, you
should immediately focus on the directories:
- /Users/username/Library
- /Network/Library (if there is a network server involved
in your case)
User “space” is contained to the user’s Home folder. All
settings, such as property list files will be found in the
Home folder Library.
When there are global settings that affect the system, you
should be looking at the folder:
Every analysis will be unique and the property list files
that you need to include to support your conclusions will
vary. If you are having trouble finding particular data,
contact us or post your question in
the
forums.