Difference between pages "Research Topics" and "Mac OS X"

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(Launch Agents)
 
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Interested in doing research in computer forensics? Looking for a master's topic, or just some ideas for a research paper? Here is our list. Please feel free to add your own ideas. ''Potential Sponsor,'' when present, indicates the name of a researcher who would be interested in lending support in the form of supervision or other resources to a project.
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{{Expand}}
  
=Tool Development=
+
Apple Inc.'s Macintosh OS X (pronounced "'''OS Ten'''") is the operating system distributed with Apple computers. It includes heavily used several programs by default, including [[Apple Mail]], a web browser called [[Apple Safari | Safari]], and an [[Apple Address Book]], and [[iCal]].  
==AFF Enhancement==
+
[[AFF]] is the Advanced Forensics Format, developed by Simson Garfinkel and Basis Technology. The following enhancements would be very useful to the format:
+
* Signing with X.509 or GPG keys data segments and metadata.
+
* Encryption of data segments with an AES-256 key specified by a password
+
* Encryption of the AES-256 key with a public key (and decryption with a corresponding private key)
+
* Evaluation of the AFF data page size. What is the optimal page size for compressed forensic work?
+
* Replacement of the AFF "BADFLAG" approach for indicating bad data with a bitmap.
+
  
''Sponsor for these projects: [[User:Simsong|Simson Garfinkel]]''
+
== Disk image types ==
  
==Flash Memory==
+
Mac OS X has support for various disk image types build-in, some of which are:
Flash memory devices such as USB keys implement a [http://www.st.com/stonline/products/literature/an/10122.htm wear leveling algorithm] in hardware so that frequently rewritten blocks are actually written to many different physical blocks. Are there any devices that let you access the raw flash cells underneath the wear leveling chip? Can you get statistics out of the device? Can you access pages that have been mapped out (and still have valid data) but haven't been mapped back yet? Can you use this as a technique for accessing deleted information?
+
* read-write disk image (.dmg) some of which use the [[Raw Image Format]]
 +
* [[Sparse Image format|Sparse disk image (.spareimage)]]
 +
* [[Sparse Bundle Image format|Sparse bundle disk image (.sparsebundle)]]
  
''Sponsor: [[User:Simsong|Simson Garfinkel]]''
+
== Burn Folder ==
 +
 
 +
Mac OS X Burn Folder:
 +
<pre>
 +
$NAME.fpbf
 +
</pre>
 +
 
 +
This folder normally contains [[Mac OS X Alias Files|alias files]] (similar to LNK files under Windows). Which should have the following signature.
 +
<pre>
 +
00000000  62 6f 6f 6b 00 00 00 00  6d 61 72 6b 00 00 00 00  |book....mark....|
 +
</pre>
 +
 
 +
These [[Mac OS X Alias Files|alias files]] contain additional date and time values.
 +
 
 +
Also check the following files for references to deleted .fpbf paths:
 +
<pre>
 +
/Users/$USERNAME/Library/Preferences/com.apple.finder.plist
 +
/Users/$USERNAME/Library/Preferences/com.apple.sidebarlists.plist
 +
</pre>
 +
 
 +
Actual burning of optical media is logged in:
 +
<pre>
 +
/var/log/system.log
 +
/Users/$USERNAME/Library/Logs/DiscRecording.log
 +
/private/var/.logs_exporter/cache/Users/$USERNAME/Library/Logs/DiscRecording.log
 +
</pre>
 +
 
 +
== HFS/HFS+ date and time values ==
 +
 
 +
In HFS+ date and time values are stored in an unsigned 32-bit integer containing the number of seconds since January 1, 1904 at 00:00:00 (midnight) UTC (GMT). This is slightly different from HFS where the date and time value are stored using the local time. The maximum representable date is February 6, 2040 at 06:28:15 UTC (GMT). The date values do not account for leap seconds. They do include a leap day in every year that is evenly divisible by four. This is sufficient given that the range of representable dates does not contain 1900 or 2100, neither of which have leap days. Also see: [http://web.archive.org/web/20090214212148/http://developer.apple.com/technotes/tn/tn1150.html Technical Note TN1150 - HFS Plus Volume Format]
 +
 
 +
Converting HFS/HFS+ date and time values with Python:
 +
<pre>
 +
import datetime
 +
 
 +
print datetime.datetime( 1904, 1, 1 ) + datetime.timedelta( seconds=0xCBDAF25B )
 +
</pre>
 +
 
 +
== Launch Agents ==
 +
System-wide:
 +
<pre>
 +
/Library/LaunchAgents
 +
/System/Library/LaunchAgents
 +
</pre>
 +
 
 +
Per user:
 +
<pre>
 +
/Users/$USERNAME/Library/LaunchAgents
 +
</pre>
 +
 
 +
These directories contain  [[Property list (plist)]] files.
 +
 
 +
== Launch Daemons ==
 +
System-wide:
 +
<pre>
 +
/Library/LaunchDaemons
 +
/System/Library/LaunchDaemons
 +
</pre>
 +
 
 +
These directories contain [[Property list (plist)]] files.
 +
 
 +
== Startup Items ==
 +
<pre>
 +
/Library/StartupItems/
 +
/System/Library/StartupItems/
 +
</pre>
 +
 
 +
== Crash Reporter ==
 +
<pre>
 +
/Library/Application Support/CrashReporter
 +
</pre>
 +
 
 +
== Diagnostic Reports ==
 +
<pre>
 +
/Library/Logs/DiagnosticReports
 +
</pre>
 +
 
 +
== Quarantine event database ==
 +
See [http://menial.co.uk/blog/2011/06/16/mac-quarantine-event-database/]
 +
 
 +
Snow Leopard and earlier
 +
<pre>
 +
/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEvents
 +
</pre>
 +
 
 +
<pre>
 +
SELECT datetime(LSQuarantineTimeStamp + 978307200, "unixepoch") as LSQuarantineTimeStamp, LSQuarantineAgentName, LSQuarantineOriginURLString, LSQuarantineDataURLString from LSQuarantineEvent;
 +
</pre>
 +
 
 +
Lion and later
 +
<pre>
 +
/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV2
 +
</pre>
 +
 
 +
== sleepimage ==
 +
This file is similar to the hibernation file on Windows.
 +
<pre>
 +
/private/var/vm/sleepimage
 +
</pre>
 +
 
 +
Also see: [http://osxdaily.com/2010/10/11/sleepimage-mac/]
 +
 
 +
== Package Files (.PKG) ==
 +
Package Files (.PKG) are XAR archives [http://en.wikipedia.org/wiki/Xar_(archiver)] that contain a cpio archive and metadata [http://s.sudre.free.fr/Stuff/Ivanhoe/FLAT.html].
 +
 
 +
== Also see ==
 +
* [[MacOS Process Monitoring]]
 +
* [[Acquiring a MacOS System with Target Disk Mode]]
 +
* [[Converting Binary Plists]]
 +
* [[FileVault Disk Encryption]]
 +
* [[File Vault]]
 +
 
 +
=== Formats ===
 +
* [[Basic Security Module (BSM) file format]]
 +
* [[Property list (plist)]]
 +
 
 +
== External Links ==
 +
* [http://www.apple.com/macosx/ Official website]
 +
* [http://en.wikipedia.org/wiki/OS_X Wikipedia entry on OS X]
 +
* [http://menial.co.uk/blog/2011/06/16/mac-quarantine-event-database/ Quarantine event database]
 +
* [http://www2.tech.purdue.edu/cit/Courses/cit556/readings/MacForensicsCraiger.pdf Mac Forensics: Mac OS X and the HFS+ File System] by P. Craiger
 +
* [http://web.me.com/driley/iWeb/Previous_files/Directory_Services_Overview.pdf Mac OS X Directory Services Integration including Active Directory]
 +
* [http://digitalinvestigation.wordpress.com/2012/04/04/geek-post-nskeyedarchiver-files-what-are-they-and-how-can-i-use-them/ NSKeyedArchiver files – what are they, and how can I use them?]
 +
* [http://krypted.com/mac-os-x/command-line-alf-on-mac-os-x/ Command Line ALF on Mac OS X]
 +
* [http://newosxbook.com/DMG.html Demystifying the DMG File Format]
 +
* [https://code.google.com/p/mac-security-tips/wiki/ALL_THE_TIPS mac-security-tips]
 +
 
 +
=== Apple Examiner ===
 +
* [http://www.appleexaminer.com/ The Apple Examiner]
 +
* [http://www.appleexaminer.com/MacsAndOS/Analysis/USBOSX/USBOSX.html USB Entries on OS X]
 +
* [http://www.appleexaminer.com/Downloads/MacForensics.pdf Macintosh Forensics - A Guide for the Forensically Sound Examination of a Macintosh Computer] by Ryan R. Kubasiak
 +
 
 +
=== iCloud ===
 +
* [http://support.apple.com/kb/HT4865?viewlocale=en_US&locale=en_US iCloud: iCloud security and privacy overview]
 +
 
 +
[[Category:Mac OS X]]
 +
[[Category:Operating systems]]

Revision as of 13:08, 12 June 2014

Information icon.png

Please help to improve this article by expanding it.
Further information might be found on the discussion page.

Apple Inc.'s Macintosh OS X (pronounced "OS Ten") is the operating system distributed with Apple computers. It includes heavily used several programs by default, including Apple Mail, a web browser called Safari, and an Apple Address Book, and iCal.

Disk image types

Mac OS X has support for various disk image types build-in, some of which are:

Burn Folder

Mac OS X Burn Folder:

$NAME.fpbf

This folder normally contains alias files (similar to LNK files under Windows). Which should have the following signature.

00000000  62 6f 6f 6b 00 00 00 00  6d 61 72 6b 00 00 00 00  |book....mark....|

These alias files contain additional date and time values.

Also check the following files for references to deleted .fpbf paths:

/Users/$USERNAME/Library/Preferences/com.apple.finder.plist
/Users/$USERNAME/Library/Preferences/com.apple.sidebarlists.plist

Actual burning of optical media is logged in:

/var/log/system.log
/Users/$USERNAME/Library/Logs/DiscRecording.log
/private/var/.logs_exporter/cache/Users/$USERNAME/Library/Logs/DiscRecording.log

HFS/HFS+ date and time values

In HFS+ date and time values are stored in an unsigned 32-bit integer containing the number of seconds since January 1, 1904 at 00:00:00 (midnight) UTC (GMT). This is slightly different from HFS where the date and time value are stored using the local time. The maximum representable date is February 6, 2040 at 06:28:15 UTC (GMT). The date values do not account for leap seconds. They do include a leap day in every year that is evenly divisible by four. This is sufficient given that the range of representable dates does not contain 1900 or 2100, neither of which have leap days. Also see: Technical Note TN1150 - HFS Plus Volume Format

Converting HFS/HFS+ date and time values with Python:

import datetime

print datetime.datetime( 1904, 1, 1 ) + datetime.timedelta( seconds=0xCBDAF25B )

Launch Agents

System-wide:

/Library/LaunchAgents
/System/Library/LaunchAgents

Per user:

/Users/$USERNAME/Library/LaunchAgents

These directories contain Property list (plist) files.

Launch Daemons

System-wide:

/Library/LaunchDaemons
/System/Library/LaunchDaemons

These directories contain Property list (plist) files.

Startup Items

/Library/StartupItems/
/System/Library/StartupItems/

Crash Reporter

/Library/Application Support/CrashReporter

Diagnostic Reports

/Library/Logs/DiagnosticReports

Quarantine event database

See [1]

Snow Leopard and earlier

/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEvents
SELECT datetime(LSQuarantineTimeStamp + 978307200, "unixepoch") as LSQuarantineTimeStamp, LSQuarantineAgentName, LSQuarantineOriginURLString, LSQuarantineDataURLString from LSQuarantineEvent;

Lion and later

/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV2

sleepimage

This file is similar to the hibernation file on Windows.

/private/var/vm/sleepimage

Also see: [2]

Package Files (.PKG)

Package Files (.PKG) are XAR archives [3] that contain a cpio archive and metadata [4].

Also see

Formats

External Links

Apple Examiner

iCloud