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recvdg.c
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recvdg.c
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/*++
Copyright (c) 1993 Microsoft Corporation
Module Name:
recvdg.c
Abstract:
This module contains routines for handling data receive for datagram
endpoints.
Author:
David Treadwell (davidtr) 7-Oct-1993
Revision History:
--*/
#include "afdp.h"
NTSTATUS
AfdSetupReceiveDatagramIrp (
IN PIRP Irp,
IN PVOID DatagramBuffer OPTIONAL,
IN ULONG DatagramLength,
IN PVOID SourceAddress,
IN ULONG SourceAddressLength
);
NTSTATUS
AfdRestartBufferReceiveDatagram (
IN PDEVICE_OBJECT DeviceObject,
IN PIRP Irp,
IN PVOID Context
);
#ifdef ALLOC_PRAGMA
#pragma alloc_text( PAGEAFD, AfdReceiveDatagram )
#pragma alloc_text( PAGEAFD, AfdReceiveDatagramEventHandler )
#pragma alloc_text( PAGEAFD, AfdSetupReceiveDatagramIrp )
#pragma alloc_text( PAGEAFD, AfdRestartBufferReceiveDatagram )
#pragma alloc_text( PAGEAFD, AfdCancelReceiveDatagram )
#pragma alloc_text( PAGEAFD, AfdCleanupReceiveDatagramIrp )
#endif
//
// Macros to make the receive datagram code more maintainable.
//
#define AfdRecvDatagramInfo DeviceIoControl
#define AfdRecvAddressLength InputBufferLength
#define AfdRecvAddressPointer Type3InputBuffer
NTSTATUS
AfdReceiveDatagram (
IN PIRP Irp,
IN PIO_STACK_LOCATION IrpSp,
IN ULONG RecvFlags,
IN ULONG AfdFlags
)
{
NTSTATUS status;
KIRQL oldIrql;
PAFD_ENDPOINT endpoint;
PLIST_ENTRY listEntry;
BOOLEAN peek;
PAFD_BUFFER afdBuffer;
ULONG recvFlags;
ULONG afdFlags;
ULONG recvLength;
PVOID addressPointer;
PULONG addressLength;
PMDL addressMdl;
PMDL lengthMdl;
//
// Set up some local variables.
//
endpoint = IrpSp->FileObject->FsContext;
ASSERT( endpoint->Type == AfdBlockTypeDatagram );
Irp->IoStatus.Information = 0;
addressMdl = NULL;
lengthMdl = NULL;
//
// If receive has been shut down or the endpoint aborted, fail.
//
// !!! Do we care if datagram endpoints get aborted?
//
if ( (endpoint->DisconnectMode & AFD_PARTIAL_DISCONNECT_RECEIVE) ) {
status = STATUS_PIPE_DISCONNECTED;
goto complete;
}
#if 0
if ( (endpoint->DisconnectMode & AFD_ABORTIVE_DISCONNECT) ) {
status = STATUS_LOCAL_DISCONNECT;
goto complete;
}
#endif
//
// Do some special processing based on whether this is a receive
// datagram IRP, a receive IRP, or a read IRP.
//
if ( IrpSp->Parameters.DeviceIoControl.IoControlCode ==
IOCTL_AFD_RECEIVE_DATAGRAM &&
IrpSp->MajorFunction == IRP_MJ_DEVICE_CONTROL ) {
PAFD_RECV_DATAGRAM_INFO recvInfo;
//
// Make sure that the endpoint is in the correct state.
//
if ( endpoint->State != AfdEndpointStateBound ) {
status = STATUS_INVALID_PARAMETER;
goto complete;
}
//
// Grab the parameters from the input structure.
//
if ( IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
sizeof(*recvInfo) ) {
try {
//
// Probe the input structure.
//
recvInfo = IrpSp->Parameters.DeviceIoControl.Type3InputBuffer;
if( Irp->RequestorMode != KernelMode ) {
ProbeForRead(
recvInfo,
sizeof(*recvInfo),
sizeof(ULONG)
);
}
//
// Snag the receive flags.
//
recvFlags = recvInfo->TdiFlags;
afdFlags = recvInfo->AfdFlags;
//
// Setup the address fields so we can return the datagram
// address to the user.
//
addressPointer = recvInfo->Address;
addressLength = recvInfo->AddressLength;
//
// Validate the WSABUF parameters.
//
if ( recvInfo->BufferArray != NULL &&
recvInfo->BufferCount > 0 ) {
//
// Create the MDL chain describing the WSABUF array.
//
status = AfdAllocateMdlChain(
Irp,
recvInfo->BufferArray,
recvInfo->BufferCount,
IoWriteAccess,
&recvLength
);
} else {
//
// Zero-length input buffer. This is OK for datagrams.
//
ASSERT( Irp->MdlAddress == NULL );
status = STATUS_SUCCESS;
}
} except ( EXCEPTION_EXECUTE_HANDLER ) {
//
// Exception accessing input structure.
//
status = GetExceptionCode();
}
} else {
//
// Invalid input buffer length.
//
status = STATUS_INVALID_PARAMETER;
}
//
// If only one of addressPointer or addressLength are NULL, then
// fail the request.
//
if( (addressPointer == NULL) ^ (addressLength == NULL) ) {
status = STATUS_INVALID_PARAMETER;
goto complete;
}
if( !NT_SUCCESS(status) ) {
goto complete;
}
//
// If the user wants the source address from the receive datagram,
// then create MDLs for the address & address length, then probe
// and lock the MDLs.
//
if( addressPointer != NULL ) {
ASSERT( addressLength != NULL );
//
// Setup so we know how to cleanup after the try/except block.
//
status = STATUS_SUCCESS;
try {
//
// Bomb off if the user is trying to do something stupid, like
// specify a zero-length address, or one that's unreasonably
// huge. Here, we (arbitrarily) define "unreasonably huge" as
// anything 64K or greater.
//
if( *addressLength == 0 ||
*addressLength >= 65536 ) {
ExRaiseStatus( STATUS_INVALID_PARAMETER );
}
//
// Create a MDL describing the address buffer, then probe
// it for write access.
//
addressMdl = IoAllocateMdl(
addressPointer, // VirtualAddress
*addressLength, // Length
FALSE, // SecondaryBuffer
TRUE, // ChargeQuota
NULL // Irp
);
if( addressMdl == NULL ) {
ExRaiseStatus( STATUS_INSUFFICIENT_RESOURCES );
}
MmProbeAndLockPages(
addressMdl, // MemoryDescriptorList
Irp->RequestorMode, // AccessMode
IoWriteAccess // Operation
);
//
// Create a MDL describing the length buffer, then probe it
// for write access.
//
lengthMdl = IoAllocateMdl(
addressLength, // VirtualAddress
sizeof(*addressLength), // Length
FALSE, // SecondaryBuffer
TRUE, // ChargeQuota
NULL // Irp
);
if( lengthMdl == NULL ) {
ExRaiseStatus( STATUS_INSUFFICIENT_RESOURCES );
}
MmProbeAndLockPages(
lengthMdl, // MemoryDescriptorList
Irp->RequestorMode, // AccessMode
IoWriteAccess // Operation
);
} except( EXCEPTION_EXECUTE_HANDLER ) {
status = GetExceptionCode();
}
if( !NT_SUCCESS(status) ) {
goto complete;
}
ASSERT( addressMdl != NULL );
ASSERT( lengthMdl != NULL );
} else {
ASSERT( addressMdl == NULL );
ASSERT( lengthMdl == NULL );
}
//
// Validate the receive flags.
//
if( ( recvFlags & TDI_RECEIVE_EITHER ) != TDI_RECEIVE_NORMAL ) {
status = STATUS_NOT_SUPPORTED;
goto complete;
}
peek = (BOOLEAN)( (recvFlags & TDI_RECEIVE_PEEK) != 0 );
} else {
ASSERT( (Irp->Flags & IRP_INPUT_OPERATION) == 0 );
if ( IrpSp->MajorFunction == IRP_MJ_DEVICE_CONTROL ) {
//
// Grab the input parameters from the IRP.
//
ASSERT( IrpSp->Parameters.DeviceIoControl.IoControlCode ==
IOCTL_AFD_RECEIVE );
recvFlags = RecvFlags;
afdFlags = AfdFlags;
//
// It is illegal to attempt to receive expedited data on a
// datagram endpoint.
//
if ( (recvFlags & TDI_RECEIVE_EXPEDITED) != 0 ) {
status = STATUS_NOT_SUPPORTED;
goto complete;
}
ASSERT( ( recvFlags & TDI_RECEIVE_EITHER ) == TDI_RECEIVE_NORMAL );
peek = (BOOLEAN)( (recvFlags & TDI_RECEIVE_PEEK) != 0 );
} else {
//
// This must be a read IRP. There are no special options
// for a read IRP.
//
ASSERT( IrpSp->MajorFunction == IRP_MJ_READ );
recvFlags = TDI_RECEIVE_NORMAL;
afdFlags = AFD_OVERLAPPED;
peek = FALSE;
}
ASSERT( addressMdl == NULL );
ASSERT( lengthMdl == NULL );
}
//
// Save the address & length MDLs in the current IRP stack location.
// These will be used later in SetupReceiveDatagramIrp(). Note that
// they should either both be NULL or both be non-NULL.
//
IoAcquireCancelSpinLock( &Irp->CancelIrql );
AfdAcquireSpinLock( &endpoint->SpinLock, &oldIrql );
ASSERT( !( ( addressMdl == NULL ) ^ ( lengthMdl == NULL ) ) );
IrpSp->Parameters.AfdRecvDatagramInfo.AfdRecvAddressPointer =
(PVOID)addressMdl;
IrpSp->Parameters.AfdRecvDatagramInfo.AfdRecvAddressLength =
(ULONG)lengthMdl;
//
// Determine whether there are any datagrams already bufferred on
// this endpoint. If there is a bufferred datagram, we'll use it to
// complete the IRP.
//
if ( endpoint->BufferredDatagramCount != 0 ) {
KIRQL saveIrql;
//
// There is at least one datagram bufferred on the endpoint.
// Use it for this receive.
//
ASSERT( !IsListEmpty( &endpoint->ReceiveDatagramBufferListHead ) );
listEntry = endpoint->ReceiveDatagramBufferListHead.Flink;
afdBuffer = CONTAINING_RECORD( listEntry, AFD_BUFFER, BufferListEntry );
//
// Prepare the user's IRP for completion.
//
status = AfdSetupReceiveDatagramIrp (
Irp,
afdBuffer->Buffer,
afdBuffer->DataLength,
afdBuffer->SourceAddress,
afdBuffer->SourceAddressLength
);
//
// Release the cancel spin lock, since we don't need it.
// However, be careful about the IRQLs because we're releasing
// locks in a different order than we acquired them.
//
saveIrql = Irp->CancelIrql;
IoReleaseCancelSpinLock( oldIrql );
oldIrql = saveIrql;
//
// If this wasn't a peek IRP, remove the buffer from the endpoint's
// list of bufferred datagrams.
//
if ( !peek ) {
RemoveHeadList( &endpoint->ReceiveDatagramBufferListHead );
//
// Update the counts of bytes and datagrams on the endpoint.
//
endpoint->BufferredDatagramCount--;
endpoint->BufferredDatagramBytes -= afdBuffer->DataLength;
endpoint->EventsActive &= ~AFD_POLL_RECEIVE;
IF_DEBUG(EVENT_SELECT) {
KdPrint((
"AfdReceiveDatagram: Endp %08lX, Active %08lX\n",
endpoint,
endpoint->EventsActive
));
}
if( endpoint->BufferredDatagramCount > 0 ) {
AfdIndicateEventSelectEvent(
endpoint,
AFD_POLL_RECEIVE_BIT,
STATUS_SUCCESS
);
}
}
//
// We've set up all return information. Clean up and complete
// the IRP.
//
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
if ( !peek ) {
AfdReturnBuffer( afdBuffer );
}
IoCompleteRequest( Irp, 0 );
return status;
}
//
// There were no datagrams bufferred on the endpoint. If this is a
// nonblocking endpoint and the request was a normal receive (as
// opposed to a read IRP), fail the request. We don't fail reads
// under the asumption that if the application is doing reads they
// don't want nonblocking behavior.
//
if ( endpoint->NonBlocking && !ARE_DATAGRAMS_ON_ENDPOINT( endpoint ) &&
!( afdFlags & AFD_OVERLAPPED ) ) {
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( Irp->CancelIrql );
status = STATUS_DEVICE_NOT_READY;
goto complete;
}
//
// We'll have to pend the IRP. Place the IRP on the appropriate IRP
// list in the endpoint.
//
if ( peek ) {
InsertTailList(
&endpoint->PeekDatagramIrpListHead,
&Irp->Tail.Overlay.ListEntry
);
} else {
InsertTailList(
&endpoint->ReceiveDatagramIrpListHead,
&Irp->Tail.Overlay.ListEntry
);
}
IoMarkIrpPending( Irp );
//
// Set up the cancellation routine in the IRP. If the IRP has already
// been cancelled, just call the cancellation routine here.
//
if ( Irp->Cancel ) {
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
AfdCancelReceiveDatagram( IrpSp->DeviceObject, Irp );
status = STATUS_CANCELLED;
goto complete;
}
IoSetCancelRoutine( Irp, AfdCancelReceiveDatagram );
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( Irp->CancelIrql );
return STATUS_PENDING;
complete:
ASSERT( !NT_SUCCESS(status) );
if( addressMdl != NULL ) {
if( (addressMdl->MdlFlags & MDL_PAGES_LOCKED) != 0 ) {
MmUnlockPages( addressMdl );
}
IoFreeMdl( addressMdl );
}
if( lengthMdl != NULL ) {
if( (lengthMdl->MdlFlags & MDL_PAGES_LOCKED) != 0 ) {
MmUnlockPages( lengthMdl );
}
IoFreeMdl( lengthMdl );
}
Irp->IoStatus.Status = status;
IoCompleteRequest( Irp, 0 );
return status;
} // AfdReceiveDatagram
NTSTATUS
AfdReceiveDatagramEventHandler (
IN PVOID TdiEventContext,
IN int SourceAddressLength,
IN PVOID SourceAddress,
IN int OptionsLength,
IN PVOID Options,
IN ULONG ReceiveDatagramFlags,
IN ULONG BytesIndicated,
IN ULONG BytesAvailable,
OUT ULONG *BytesTaken,
IN PVOID Tsdu,
OUT PIRP *IoRequestPacket
)
/*++
Routine Description:
Handles receive datagram events for nonbufferring transports.
Arguments:
Return Value:
--*/
{
KIRQL oldIrql;
KIRQL cancelIrql;
PAFD_ENDPOINT endpoint;
PLIST_ENTRY listEntry;
PAFD_BUFFER afdBuffer;
PIRP irp;
ULONG requiredAfdBufferSize;
BOOLEAN userIrp;
endpoint = TdiEventContext;
ASSERT( endpoint != NULL );
ASSERT( endpoint->Type == AfdBlockTypeDatagram );
#if AFD_PERF_DBG
if ( BytesAvailable == BytesIndicated ) {
AfdFullReceiveDatagramIndications++;
} else {
AfdPartialReceiveDatagramIndications++;
}
#endif
//
// If this endpoint is connected and the datagram is for a different
// address than the one the endpoint is connected to, drop the
// datagram. Also, if we're in the process of connecting the
// endpoint to a remote address, the MaximumDatagramCount field will
// be 0, in which case we shoul drop the datagram.
//
IoAcquireCancelSpinLock( &cancelIrql );
AfdAcquireSpinLock( &endpoint->SpinLock, &oldIrql );
if ( (endpoint->State == AfdEndpointStateConnected &&
!AfdAreTransportAddressesEqual(
endpoint->Common.Datagram.RemoteAddress,
endpoint->Common.Datagram.RemoteAddressLength,
SourceAddress,
SourceAddressLength,
TRUE )) ||
(endpoint->Common.Datagram.MaxBufferredReceiveCount == 0) ) {
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( cancelIrql );
*BytesTaken = BytesAvailable;
return STATUS_SUCCESS;
}
//
// Check whether there are any IRPs waiting on the endpoint. If
// there is such an IRP, use it to receive the datagram.
//
if ( !IsListEmpty( &endpoint->ReceiveDatagramIrpListHead ) ) {
ASSERT( *BytesTaken == 0 );
ASSERT( endpoint->BufferredDatagramCount == 0 );
ASSERT( endpoint->BufferredDatagramBytes == 0 );
listEntry = RemoveHeadList( &endpoint->ReceiveDatagramIrpListHead );
//
// Get a pointer to the IRP and reset the cancel routine in
// the IRP. The IRP is no longer cancellable.
//
irp = CONTAINING_RECORD( listEntry, IRP, Tail.Overlay.ListEntry );
IoSetCancelRoutine( irp, NULL );
//
// If the entire datagram is being indicated to us here, just
// copy the information to the MDL in the IRP and return.
//
// Note that we'll also take the entire datagram if the user
// has pended a zero-byte datagram receive (detectable as a
// NULL Irp->MdlAddress). We'll eat the datagram and fall
// through to AfdSetupReceiveDatagramIrp(), which will store
// an error status in the IRP since the user's buffer is
// insufficient to hold the datagram.
//
if( BytesIndicated == BytesAvailable ||
irp->MdlAddress == NULL ) {
//
// Set BytesTaken to indicate that we've taken all the
// data. We do it here because we already have
// BytesAvailable in a register, which probably won't
// be true after making function calls.
//
*BytesTaken = BytesAvailable;
//
// Copy the datagram and source address to the IRP. This
// prepares the IRP to be completed.
//
// !!! do we need a special version of this routine to
// handle special RtlCopyMemory, like for
// TdiCopyLookaheadBuffer?
//
(VOID)AfdSetupReceiveDatagramIrp (
irp,
Tsdu,
BytesAvailable,
SourceAddress,
SourceAddressLength
);
//
// The IRP is off the endpoint's list and is no longer
// cancellable. We can release the locks we hold.
//
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( cancelIrql );
//
// Complete the IRP. We've already set BytesTaken
// to tell the provider that we have taken all the data.
//
IoCompleteRequest( irp, AfdPriorityBoost );
return STATUS_SUCCESS;
}
//
// Some of the datagram was not indicated, so remember that we
// want to pass back this IRP to the TDI provider. Passing back
// this IRP directly is good because it avoids having to copy
// the data from one of our buffers into the user's buffer.
//
userIrp = TRUE;
requiredAfdBufferSize = 0;
} else {
userIrp = FALSE;
requiredAfdBufferSize = BytesAvailable;
}
//
// There were no IRPs available to take the datagram, so we'll have
// to buffer it. First make sure that we're not over the limit
// of bufferring that we can do. If we're over the limit, toss
// this datagram.
//
if ( endpoint->BufferredDatagramCount >=
endpoint->Common.Datagram.MaxBufferredReceiveCount ||
endpoint->BufferredDatagramBytes >=
endpoint->Common.Datagram.MaxBufferredReceiveBytes ) {
//
// If circular queueing is not enabled, then just drop the
// datagram on the floor.
//
if( !endpoint->Common.Datagram.CircularQueueing ) {
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( cancelIrql );
*BytesTaken = BytesAvailable;
return STATUS_SUCCESS;
}
//
// Circular queueing is enabled, so drop packets at the head of
// the receive queue until we're below the receive limit.
//
while( endpoint->BufferredDatagramCount >=
endpoint->Common.Datagram.MaxBufferredReceiveCount ||
endpoint->BufferredDatagramBytes >=
endpoint->Common.Datagram.MaxBufferredReceiveBytes ) {
listEntry = RemoveHeadList( &endpoint->ReceiveDatagramBufferListHead );
afdBuffer = CONTAINING_RECORD( listEntry, AFD_BUFFER, BufferListEntry );
endpoint->BufferredDatagramCount--;
endpoint->BufferredDatagramBytes -= afdBuffer->DataLength;
AfdReturnBuffer( afdBuffer );
}
//
// Proceed to accept the incoming packet.
//
}
//
// We're able to buffer the datagram. Now acquire a buffer of
// appropriate size.
//
afdBuffer = AfdGetBuffer( requiredAfdBufferSize, SourceAddressLength );
if ( afdBuffer == NULL ) {
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( cancelIrql );
*BytesTaken = BytesAvailable;
return STATUS_SUCCESS;
}
//
// If the entire datagram is being indicated to us, just copy it
// here.
//
if ( BytesIndicated == BytesAvailable ) {
ASSERT( !userIrp );
//
// If there is a peek IRP on the endpoint, remove it from the
// list and prepare to complete it. We can't complete it now
// because we hold a spin lock.
//
if ( !IsListEmpty( &endpoint->PeekDatagramIrpListHead ) ) {
//
// Remove the first peek IRP from the list and get a pointer
// to it.
//
listEntry = RemoveHeadList( &endpoint->PeekDatagramIrpListHead );
irp = CONTAINING_RECORD( listEntry, IRP, Tail.Overlay.ListEntry );
//
// Reset the cancel routine in the IRP. The IRP is no
// longer cancellable, since we're about to complete it.
//
IoSetCancelRoutine( irp, NULL );
//
// Copy the datagram and source address to the IRP. This
// prepares the IRP to be completed.
//
(VOID)AfdSetupReceiveDatagramIrp (
irp,
Tsdu,
BytesAvailable,
SourceAddress,
SourceAddressLength
);
} else {
irp = NULL;
}
//
// We don't need the cancel spin lock any more, so we can
// release it. However, since we acquired the cancel spin lock
// after the endpoint spin lock and we still need the endpoint
// spin lock, be careful to switch the IRQLs.
//
IoReleaseCancelSpinLock( oldIrql );
oldIrql = cancelIrql;
//
// Use the special function to copy the data instead of
// RtlCopyMemory in case the data is coming from a special place
// (DMA, etc.) which cannot work with RtlCopyMemory.
//
TdiCopyLookaheadData(
afdBuffer->Buffer,
Tsdu,
BytesAvailable,
ReceiveDatagramFlags
);
//
// Store the data length and set the offset to 0.
//
afdBuffer->DataLength = BytesAvailable;
ASSERT( afdBuffer->DataOffset == 0 );
//
// Store the address of the sender of the datagram.
//
RtlCopyMemory(
afdBuffer->SourceAddress,
SourceAddress,
SourceAddressLength
);
afdBuffer->SourceAddressLength = SourceAddressLength;
//
// Place the buffer on this endpoint's list of bufferred datagrams
// and update the counts of datagrams and datagram bytes on the
// endpoint.
//
InsertTailList(
&endpoint->ReceiveDatagramBufferListHead,
&afdBuffer->BufferListEntry
);
endpoint->BufferredDatagramCount++;
endpoint->BufferredDatagramBytes += BytesAvailable;
//
// All done. Release the lock and tell the provider that we
// took all the data.
//
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
//
// Indicate that it is possible to receive on the endpoint now.
//
AfdIndicatePollEvent(
endpoint,
AFD_POLL_RECEIVE_BIT,
STATUS_SUCCESS
);
//
// If there was a peek IRP on the endpoint, complete it now.
//
if ( irp != NULL ) {
IoCompleteRequest( irp, AfdPriorityBoost );
}
*BytesTaken = BytesAvailable;
return STATUS_SUCCESS;
}
//
// We'll have to format up an IRP and give it to the provider to
// handle. We don't need any locks to do this--the restart routine
// will check whether new receive datagram IRPs were pended on the
// endpoint.
//
AfdReleaseSpinLock( &endpoint->SpinLock, oldIrql );
IoReleaseCancelSpinLock( cancelIrql );
//
// Use the IRP in the AFD buffer if appropriate. If userIrp is
// TRUE, then the local variable irp will already point to the
// user's IRP which we'll use for this IO.
//
if ( !userIrp ) {
irp = afdBuffer->Irp;
ASSERT( afdBuffer->Mdl == irp->MdlAddress );
}
//
// Tell the TDI provider where to put the source address.
//
afdBuffer->TdiOutputInfo.RemoteAddressLength = afdBuffer->AllocatedAddressLength;
afdBuffer->TdiOutputInfo.RemoteAddress = afdBuffer->SourceAddress;