1. Winsock Kernel Best Practices
WinHEC 2006
4/11/ :44 AM
Winsock Kernel Best Practices
Osman N. Ertugay Software Design Engineer Windows Network Developer Platform Microsoft Corporation
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

2. Session Outline Brief Winsock Kernel (WSK) refresher
WinHEC 2006
4/11/ :44 AM
Session Outline
Brief Winsock Kernel (WSK) refresher
Familiarity with WSK documentation and WSK sample in WDK ensures the most benefit from this session
WSK programming guidelines and best practices
WSK registration and deregistration
I/O Request Packet (IRP) handling
Buffer ownership and manipulation
Using socket callbacks versus socket functions
Memory/throughput tradeoff in stream data transfer
Transport Address security
Dual-family sockets
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

3. WSK Refresher Kernel-mode Network Programming Interface
WinHEC 2006
4/11/ :44 AM
WSK Refresher
Kernel-mode Network Programming Interface
WSK replaces the Transport Driver Interface (TDI) for “consumers” of TDI (i.e., TDI clients)
WSK is not a “provider” interface for new transport development
WSK goals/benefits
Easier to use, consistent API
Higher performance, better scalability
Better fit for the Next Generation TCP/IP Stack
Similar to Winsock2, but not the same
Easy to port to for existing TDI clients
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

4. WSK Registration Library Network Module Registrar (NMR)
WinHEC 2006
4/11/ :44 AM
WSK Refresher
User-mode
Kernel-mode
WSK Client Driver
WSK_CLIENT
WSK_SOCKET
WSK Registration
Client Callbacks
Client Functions
Socket Callbacks
Socket Functions
WSK
WSK Registration Library
I/O Manager
WSK Subsystem
Network Module Registrar (NMR)
...
TCP (IPv6/IPv4)
UDP (IPv6/IPv4)
Raw (IPv6/IPv4)
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

5. WSK Programming Guidelines And Best Practices
WinHEC 2006
4/11/ :44 AM
WSK Programming Guidelines And Best Practices
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

6. WSK Registration And Deregistration
WinHEC 2006
4/11/ :44 AM
WSK Registration And Deregistration
Use the new WSK registration library:
WskRegister WskDeregister WskCaptureProviderNPI WskReleaseProviderNPI
const WSK_CLIENT_DISPATCH WskSampleClientDispatch = {
MAKE_WSK_VERSION(1, 0), // WSK version 1.0
0, // Reserved
NULL // No WskClientEvent callback in WSK version 1.0 };
WSK_REGISTRATION WskSampleRegistration;
NTSTATUS
DriverEntry(. . .) {
NTSTATUS status;
WSK_CLIENT_NPI wskClientNpi;
. . .
wskClientNpi.ClientContext = NULL;
wskClientNpi.Dispatch = &WskSampleClientDispatch;
status = WskRegister(&wskClientNpi, &WskSampleRegistration); }
Network Module Registrar APIs still available
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

7. WSK Registration And Deregistration
WinHEC 2006
4/11/ :44 AM
WSK Registration And Deregistration
Capture the WSK_PROVIDER_NPI, use it, release it
Do NOT use the WSK_PROVIDER_NPI after releasing it
WaitTimeOut usage in WskCaptureProviderNPI
WSK_NO_WAIT
WSK_INFINITE_WAIT Do NOT use if calling from DriverEntry!
NTSTATUS
SomeWorkerRoutine(. . .) {
NTSTATUS status;
WSK_PROVIDER_NPI wskProviderNpi;
. . .
status = WskCaptureProviderNPI(&WskSampleRegistration,
WSK_INFINITE_WAIT, &wskProviderNpi);
if(NT_SUCCESS(status)) {
status = wskProviderNpi.Dispatch->WskSocket(
wskProviderNpi.Client, AF_INET6, . . .);
WskReleaseProviderNPI(&WskSampleRegistration); }
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

8. WSK Registration And Deregistration
WinHEC 2006
4/11/ :44 AM
WSK Registration And Deregistration
WskDeregister
Must be called exactly once for each successful WskRegister when WSK client stops using WSK
Will block until
All captured provider NPI instances are returned
All outstanding calls to provider NPI functions completed
All sockets are closed
Must close all sockets and release all captured provider NPI instances for WskDeregister to return
Will cause WskCaptureProviderNPI calls waiting in other threads (with WSK_INFINITE_WAIT or some timeout) to return
VOID
DriverUnload(. . .) {
. . .
WskDeregister(&WskSampleRegistration); }
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

9. IRP Handling WSK Client IO Manager WSK Subsystem WinHEC 2006
4/11/ :44 AM
IRP Handling
WSK Client
IO Manager
WSK Subsystem
IoAllocateIrp(1, …)
IoSetCompletionRoutine(Irp,
CompletionRoutine, Context,
TRUE, TRUE, TRUE)
WskSend(Socket, …, Irp)
IoCompleteRequest(Irp, …)
CompletionRoutine(…, Irp, Context)
STATUS_MORE_PROCESSING_REQUIRED
IoFreeIrp(Irp)
IoReuseIrp(Irp, …)
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

10. Simple example that waits for IRP completion synchronously
WinHEC 2006
4/11/ :44 AM
IRP Handling
Simple example that waits for IRP completion synchronously
(Also demonstrating how to distinguish and optimize for “inline” IRP completion)
NTSTATUS
SyncIrpCompRtn(PDEVICE_OBJECT Reserved, PIRP Irp, PVOID Context) {
PKEVENT compEvent = (PKEVENT)Context;
if(Irp->PendingReturned)
KeSetEvent(compEvent, 2, FALSE);
return STATUS_MORE_PROCESSING_REQUIRED; }
SetSocketOption(PWSK_SOCKET Socket, . . .)
NTSTATUS status;
CONST WSK_PROVIDER_BASIC_DISPATCH *dispatch = Socket->Dispatch;
KEVENT compEvent;
PIRP irp;
KeInitializeEvent(&compEvent, SynchronizationEvent, FALSE);
irp = IoAllocateIrp(1, FALSE);
if(irp == NULL)
return STATUS_INSUFFICIENT_RESOURCES;
IoSetCompletionRoutine(irp, SyncIrpCompRtn, &compEvent, TRUE, TRUE, TRUE);
status = dispatch->WskControlSocket(Socket, . . ., irp);
if(status == STATUS_PENDING)
KeWaitForSingleObject(&compEvent, Executive, KernelMode, FALSE, NULL);
status = irp->IoStatus.Status;
IoFreeIrp(irp);
return status;
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

11. Buffer Ownership And Manipulation
WinHEC 2006
4/11/ :44 AM
Buffer Ownership And Manipulation
Setting up a WSK_BUF
WSK_BUF.Mdl
IoAllocateMdl(BufferAddress, BufferLength, . . .)
MmProbeAndLockPages vs MmBuildMdlForNonPagedPool
WSK_BUF.Length
Must be <= (BufferLength – WSK_BUF.Offset)
BufferAddress
BufferLength
MDL ByteOffset
WSK_BUF.Length
Page Boundary
WSK_BUF.Offset
WSK_BUF.Offset
Must lie within the first MDL if WSK_BUF.Mdl points to a chain of MDLs
WSK_BUF.Mdl
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

12. Buffer Ownership And Manipulation
WinHEC 2006
4/11/ :44 AM
Buffer Ownership And Manipulation
Example: Copy data from WSK_DATA_INDICATION list to a buffer
NTSTATUS
CopyDataIndicationListToBuffer(__in PWSK_DATA_INDICATION DataIndication,
__in SIZE_T BufSize, __out_bcount(BufferSize) PUCHAR Buf) {
SIZE_T bytesCopied = 0;
while(DataIndication != NULL) {
PMDL mdl = DataIndication->Buffer.Mdl;
ULONG offset = DataIndication->Buffer.Offset;
SIZE_T length = DataIndication->Buffer.Length;
while(length > 0 && mdl != NULL) {
SIZE_T copyLength = min(length, MmGetMdlByteCount(mdl)-offset);
PUCHAR sysAddr = (PUCHAR)MmGetSystemAddressForMdlSafe(mdl, LowPagePriority);
if(sysAddr == NULL)
return STATUS_INSUFFICIENT_RESOURCES;
else if((BufSize-bytesCopied) < copyLength)
return STATUS_BUFFER_TOO_SMALL;
RtlCopyMemory(Buf+bytesCopied, sysAddr+offset, copyLength);
offset = 0; // WSK_BUF.Offset applies only to the first MDL
bytesCopied += copyLength;
length -= copyLength;
mdl = mdl->Next; }
DataIndication = DataIndication->Next;
return STATUS_SUCCESS;
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

13. Buffer Ownership And Manipulation
WinHEC 2006
4/11/ :44 AM
Buffer Ownership And Manipulation
May “retain” (take temporary ownership of) a WSK data indication by returning STATUS_PENDING from WskReceiveEvent or WskReceiveFromEvent callbacks
Any status other than STATUS_PENDING means data indication was NOT retained, hence no need to call WskRelease
Must release retained data indications via WskRelease
Do not retain data indications with WSK_FLAG_RELEASE_ASAP flag if possible. If you do have to retain such indications, release them within a bounded short amount of time (in the order of a few seconds)
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

14. Socket Callbacks Versus Functions
WinHEC 2006
4/11/ :44 AM
Socket Callbacks Versus Functions
Accepting incoming connections
WskAccept
Client keeps one or more accept IRPs pended in WSK
Connections rejected by WSK when no pending IRP exists
WskAcceptEvent
WSK hands over “sockets” to client for arriving connections
Client accepts or rejects
Guidance
Use WskAcceptEvent to accept as many connections as the system can handle at any given time
Use WskAccept to accept only a few fixed number of connections at any given time
WSK does not have equivalent of listen backlog in Winsock2
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

15. Socket Callbacks Versus Functions
WinHEC 2006
4/11/ :44 AM
Socket Callbacks Versus Functions
Receiving datagrams
WskReceiveFrom
Data buffer owned by client, must allocate before data arrives
Client keeps one or more receive IRPs pended in WSK
Datagrams dropped by WSK when no pending IRP exists
WskReceiveFromEvent
Data buffer owned by WSK, allocated when data arrives
Each arriving datagram handed over to client by WSK
Guidance
Always use WskReceiveFromEvent as long as you do not retain datagram indications too long
Use WskReceiveFrom only if you must always copy datagrams into your own buffers anyway
WSK does not buffer datagrams
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

16. Socket Callbacks Versus Functions
WinHEC 2006
4/11/ :44 AM
Socket Callbacks Versus Functions
Receiving stream data
WskReceive
Data buffer owned by client, must allocate before data arrives
0-copy into client buffer possible
Data buffered by transport if no pending receive IRP exists
WskReceiveEvent
Data buffer owned by WSK
0-copy into client buffer not possible
Data handed over to client until client rejects indication
Client needs to use WskReceive to retrieve rejected data
Guidance
Use WskReceive for large block transfers
Combined usage: Get initial data via WskReceiveEvent, then get rest of the data via WskReceive
WskReceiveEvent  Amount of retained data and the time retained must be bounded and small
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

17. Socket Callbacks Versus Functions
WinHEC 2006
4/11/ :44 AM
Socket Callbacks Versus Functions
Both socket callbacks and the IRP completions for socket functions mostly occur in Deferred Procedure Call (DPC) context
Must limit amount of processing in callback and IRP completion routines
Consider using
System worker threads for tasks that won’t last too long
Dedicated system thread for long lasting tasks
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

18. Memory/Throughput Tradeoff
WinHEC 2006
4/11/ :44 AM
Memory/Throughput Tradeoff
Stream sockets  subject to transport flow control
Send requests may remain pended until acknowledged by peer
Too much pended send data  Poor memory usage
Too little pended send data  Suboptimal throughput
So, how much data to keep pended (Ideal send backlog: “ISB”)?
As much as the network can sustain
As much as the receiver can sustain
Use the SIO_WSK_QUERY_IDEAL_SEND_BACKLOG IOCTL and the WskSendBacklogEvent callback
Initial ISB to use  SIO_WSK_QUERY_IDEAL_SEND_BACKLOG
Get ISB change notifications  WskSendBacklogEvent
Always have two or more WskSend requests pended with ISB worth of data in total. Example: ISB = 64 K  2 WskSend requests, each with 32 K data
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

19. Transport Address Security
WinHEC 2006
4/11/ :44 AM
Transport Address Security
Secure by default: Creating socket with NULL SecurityDescriptor and binding it to an address results in SO_EXCLUSIVEADDRUSE behavior
Refrain from designing applications based on address sharing
If you must allow address sharing
May set SO_REUSEADDR to TRUE  Anybody else can reuse the address (not good from security perspective)
May use a SecurityDescriptor  Sharing is allowed/denied based on an access check performed by the system
WSK (transport) uses the SecurityDescriptor specified by the first socket and the SECURITY_SUBJECT_CONTEXT captured from the OwningProcess and OwningThread specified by the second socket to perform the access check
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

20. WinHEC 2006
4/11/ :44 AM
Dual Family Sockets
Use a single IPv6 socket to handle both IPv6 and IPv4 traffic
Set the IPV6_V6ONLY option to FALSE (default is TRUE)
Bind to wildcard address
// Example dual family listening socket
ULONG optVal = 0;
. . .
status = dispatch->WskControlSocket(IPv6ListeningSocket, WskSetOption,
IPV6_V6ONLY, IPPROTO_IPV6, sizeof(optVal), &optVal,
0, NULL, NULL, irp);
status = dispatch->WskBind(IPv6ListeningSocket,
(PSOCKADDR)Ipv6WildcardAddress, 0, irp);
IPv4 addresses represented in V4MAPPED IPv6 address format
Can use the INETADDR_ISV4MAPPED macro from mstcpip.h to check if a given SOCKADDR represents a V4MAPPED address
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

21. WinHEC 2006
4/11/ :44 AM
Call To Action
Port your existing kernel-mode TDI applications to WSK and use WSK for new development
Move from using TDI filter drivers to WFP for network traffic interception
Follow the practices outlined in this session to achieve optimal performance and stability from WSK
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

22. Additional Resources Web Resources Related Sessions E-mail:
WinHEC 2006
4/11/ :44 AM
Additional Resources
Web Resources
Windows Network Developer Platform (WNDP) Team Blog
WNDP Team Connect Site
Join the ‘WNDP’ program at
Related Sessions
How to Use the Windows Filtering Platform to Integrate with Windows Networking
Using NDIS 6.0, TCP Chimney Offload, and RSS to Achieve High Performance Networking
microsoft.com
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

23. WinHEC 2006
4/11/ :44 AM
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

24. WinHEC 2006
4/11/ :44 AM
© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.