e-communication masthead image
e-communication logo image
Edition for
October 19, 2004
This newsletter contains archived content. No warranty is made as to technical accuracy of content or currency of URLs.

DIFx Tools   

Driver developers should be careful when using handles, especially those received from user-mode applications.

First, such handles are specific to a process context, so they're only valid in the process that opened the handle. When used from a different process context or from a worker thread, the handle could reference a different object or it could simply be invalid.

Second, an attacker might close and reopen the handle to change what it refers to while the driver is using it.

Third, an attacker might pass in such a handle to trick a driver into performing operations that are illegal for the application, such as calling ZwXxx functions. Access checks are skipped for kernel-mode callers of these functions, so an attacker can use this mechanism to bypass validation.

Drivers should also make certain that user-mode applications cannot misuse handles created by the driver; one solution is to use kernel handles, which cannot be accessed, closed, or replaced by user-mode applications.

Never assume a handle is valid; always make sure that the handle has the correct object type, appropriate access for the required tasks, and the correct access mode, and that the access mode is compatible with the access requested.

See details and sample code for handles on WHDC

DDK MVP Highlight

NDIS Driver Compile Flags
Stephan Wolf, a DDK MVP, provides some tips and tricks for overcoming pitfalls with compile-time flags for NDIS Drivers.

News for Kernel-Mode Developers

File System Filter Drivers
A file system filter driver intercepts requests targeted at a file system or another file system filter driver. By intercepting the request before it reaches its intended target, the filter driver can extend or replace functionality provided by the original target of the request. Examples of file system filter drivers include anti-virus filters, backup agents, and encryption products.

Readings and Resources on File System Filter Drivers

Windows Driver Foundation Beta Program Invitation
The Microsoft Windows Device Experience Group invites you to participate in the beta program for the Windows Driver Foundation.

Invitation and Introduction to WDF

Device-Class Tips & News

PNP and HD Audio
As part of the Universal Audio Architecture (UAA) initiative, Microsoft has developed a set of Plug and Play guidelines for identifying High Definition Audio codec and bus controller devices. These guidelines allow an HD Audio device to be identified with greater precision than possible with the Plug and Play device-identification system for AC'97 devices.

Plug and Play Guidelines for High Definition Audio Devices

More Audio Device and Driver Guidelines...

More Device Fundamentals - Overview...

Kits, Tools, Services, and Programs

Designed for Windows Media Center Edition Logo Program
Created in response to customer and partner feedback, this program is provided to help educate consumers and partners about which related components and peripherals deliver the best experience with a Windows XP Media Center Edition PC. The initial program includes these components: Media Center remote controls, TV tuner cards, video cards, DVD Decoders, Media Center extender devices, and related wireless network access points and bridges optimized for audio-visual streaming.

Submission Details for "Designed for Windows Media Center Edition" Logo Program

Introducing Windows Marketplace
Include your Microsoft Windows-compatible software and hardware products in the upcoming Windows Marketplace: a comprehensive, easy-to-use shopping and download site that will help Windows customers discover, experience, and purchase partner products and software. Millions of customers will access Windows Marketplace through the Windows XP Start Menu and Internet Explorer, and will hear about this great destination through a variety of Microsoft marketing vehicles.

Windows Marketplace and the Microsoft Partner Program

Tips and Directions for Testing

Event Tracing for Windows
Event tracing is a technique for obtaining diagnostic information about running code without the overhead of a checked build or use of a debugger. An event represents any discrete activity of interest, especially with respect to performance.

Readings and Guidelines for Event Tracing

More Tools for Testing and Tuning: Overview...

Security and Reliability

Install Critical Updates for Windows and Office

More Driver Security and Reliability...

What else is new on WHDC?

DDK MVP Expert Zone

Extreme MVP: If every driver writer would just...

Insights and Tips from DDK MVPs

WHDC Ask The Experts

Windows Kernel Plug and Play and Power Management
October 20, 2004
17:00-18:00 GMT

Details for WHDC Ask the Experts

Resources for Developers

Debugging Tools for Windows - Version 6.3.17.0

Which DDK and HCT to Use?

KB Articles for the DDK

Events and Errors Message Center

WinHEC and Driver DevCon

WinHEC US 2005
April 25-27, 2005
Washington State Convention and Trade Center

Driver DevCon 2005
April 25-28, 2005
NDA-only, Seattle Sheraton

WinHEC Taipei 2005
May 17-18, 2005
Taipei International Convention Center

Registration for these events begins in early 2005. To receive information about partner participation in November, please send e-mail to pavilion@microsoft.com.

To cancel your subscription to this newsletter, reply to this message with the word UNSUBSCRIBE in the Subject line. You can also unsubscribe at http://www.microsoft.com/misc/unsubscribe.htm. You can manage all your Microsoft.com communication preferences at this site.

 Legal Information.

This newsletter was sent by the Microsoft Corporation
1 Microsoft Way
Redmond, Washington, USA
98052
Sign up for other newsletters | Unsubscribe | Update your profile
© 2004 Microsoft Corporation Terms of Use | Privacy Statement 		Microsoft