Content for File System or File System Filter Developers
With growing interest in the file systems developement space, we've dedicated an entire section of OSR Online to related endeavors. From FAQs to articles specific to file systems or file system filter drivers, return here for the most pertinent information.
Windows 8 Preview: File System Changes
The NT Insider, Vol 18, Issue 3, Sept-Oct 2011 (Read 12542 times)
Getting Away From It All: The Isolation Driver (Part II)
The NT Insider, Volume 18, Issue 1 , January-February 2011 (Read 10580 times)
This second article in a series addressing the topic of "isolation" drivers in Windows begins to examine some of the fundamental issues involved in creating an isolation driver.
File Systems and Filters: A Specialty
OSR Staff (Read 23405 times)
If you're a Windows file system or file system filter driver developer, this section is for you.
Getting Away From It All: The Isolation Driver (Part I)
The NT Insider, Volume 17, Issue 2 , July-August 2010 (Read 12388 times)
This article begins to delve into what we're calling "isolation drivers". This part of a multipart series begins by laying some groundwork for the isolation model, which we'll pick up in follow-on pieces to bring us to the conclusion that will include sample code.
Writing Filters is Hard Work: Undocumented DFS & RDR Interactions
The NT Insider, Volume 17, Issue 2 , July-August 2010 (Read 13699 times)
There's time when we wonder how file system filter/mini-filter developers make any progress. This article pinpoints some particularly painful problems we came across in our own work -specific to Windows Distributed File System (DFS) and file system Redirector (RDR) components.
File Systems, File System Filter Drivers and Removable Storage Devices
The NT Insider, Volume 16, Issue 2, May-June 2009 (Read 11888 times)
What does USB have to do with Windows file systems development? Well, not much, but if you think about plug and play and device and media state changes, you'll be happy to have read this article.
Filtering File Systems - Then Things You Should Know
The NT Insider, Volume 16, Issue 1, Jan-Feb 2009 (Read 14375 times)
If you are building a file system filter driver because you think it will be "simpler" than a file system driver, you are likely to be unpleasantly surprised.
(Un)Expected Behavior: Windows Vista and File Systems
The NT Insider, Vol 14, Issue 4, November - December 2007 (Read 10082 times)
The varying behavior of Windows file systems in each O/S release has always been a challenge for those utilizing the file system interface for commerical solutions. The onset of Vista is no different, but this article picks out a few subtle ones that can bite you if you're not careful.
OSR Staff (Read 144835 times)
Finding useful technical information in the Windows file system development space is difficult. If the information IS out there, it's sometimes difficult to track down. Here, we provide an FAQ of common questions to help. If you have suggestions, please feel free to add comments!
OSR+Microsoft Team Up: Offer Minifilter Seminar for Plugfest
OSR Staff (Read 11611 times)
OSR and Microsoft are teaming-up to offer special discounts to Plugfest 18 attendees.
MmGetSystemRoutineAddress IS BROKEN!?
OSR Staff (Read 20792 times)
Yikes! Can it be that the widely publicized and used function MmGetSystemRoutineAddress can blue screen on XP SP2?? Well...
Guest Article: C++ in an NT Driver
The NT Insider, Vol 14, Issue 2, March - April 2007 (Read 18591 times)
An ever increasing number of programmers are willing to try C++ in kernel mode; but why would you use C++? Let guest author Edouard Alligand show you how useful C++ can be.
MUP Changes in Windows Vista
The NT Insider, Vol 14, Issue 1, January - February 2007 (Read 7794 times)
Do you implement legacy file system filter drivers and monolithic redirectors? Well then you will be particularly interested in how changes in Windows Vista relate to the way that the Multiple UNC Provider (MUP) driver functions.
Back to Basics - An Introduction to Transactions
The NT Insider, Vol 14, Issue 1, January - February 2007 (Read 8664 times)
The introduction of transactions will substantially impact those of us who operate in the file systems space. Here's a simple primer for describing how a basic transactional system works.
Windows Streams - An Introduction to File System Streams
The NT Insider, Vol 13, Issue 2, March - April 2006 (Read 45988 times)
Are you fuzzy on the NTFS concept of "streams" in files? This article explains streams and how they're used.
Another Book Announcement? - OSR Press to Reprint Windows NT File System Internals
(Read 12113 times)
If you've tried to find a copy of Nagar's Windows NT File System Internals (first published in 1997) you've probably been disappointed. Sure, some of its details are out of date, but much of the information is still current and still valuable. That's why OSR Press is reprinting this classic. Read more...
Relative opens and IoCreateFileSpecifyDeviceObjectHint
Hector J. Rodriguez (Read 12971 times)
Sometimes, even I have to be reminded about the bugs, er, rules.
Watch that return from IoSetCompletionRoutineEx
Hector J. Rodriguez (Read 11503 times)
There are two things to be careful of, here: Don't forget about the NTSTATUS value, and pass that IRP to another driver.
Need help with WPP tracing?
Hector J. Rodriguez (Read 16012 times)
WPP got you down? It seems like everyone wants to using WPP tracing, but not everyone is able to get it working. Here's a three pack of tips from the battlefront that might save you some time...
Beware the old SFilter!
OSR Staff (Read 15044 times)
This article describes a problem that we have observed multiple times in file system filter drivers. It arises because of the way older versions of SFILTER (in the IFS Kit) were implemented. Newer versions do not behave in this fashion and do not exhibit this problem.
Security During Create Operations
OSR Staff (Read 24755 times)
This article describes how Windows file systems that support security go about assigning a new security descriptor during the processing of IRP_MJ_CREATE. This article is not intended to be a comprehensive description of all the steps, but rather a basic review of how a file system handles it.
Notes on Installing Mini Filters
OSR Staff (Read 18242 times)
Now that the Filter Manager model is no longer confidential, we've started making notes of our experiences with it. This article discusses installation of Filter Manager based file system filters and some of the things we've learned in that process.
How Do I Replace A System File? Try .KDFILES
OSR Staff (Read 24217 times)
The DDK and IFS Kit include buildable drivers but the system file protection feature in Windows makes it difficult to replace the file. This article describes a simple techinque, using the kernel debugger, to replace that file and bypass system file protection.
Mapping Win32 to Internal File Creation Options
OSR Staff (Read 17575 times)
This article describes the way that Win32 maps file creation options to the underlying Windows file creation options.
How Are Files Deleted In Windows
OSR Staff (Read 21478 times)
A periodic question in the NTFSD mailing list is to describe the process by which files are deleted. This article describes the basic model used by the Windows file systems for file (and directory) deletion.
Caching in Network File Systems
OSR Staff (Read 23850 times)
This article discusses the issues of caching in the RDBSS package which is used by RDR2. This information is particularly useful for those building file system filter drivers.
A Brief Explanation of FsRtlCheckOplock
OSR Staff (Read 14816 times)
This brief article describes the mysterious workings of FsRtlCheckOplock. This call is primarily used by file systems that implement oplocks. Typically, this is physical media or pseudo file systems (but NOT network file systems).