Leaked source code of windows server 2003
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

362 lines
10 KiB

/*++
Copyright (c) 1992 Microsoft Corporation
Module Name:
detect.c
Abstract:
Author:
Thomas J. Dimitri (TommyD) 08-May-1992
Environment:
Kernel Mode - Or whatever is the equivalent on OS/2 and DOS.
Revision History:
--*/
#include "asyncall.h"
VOID
SerialFlushReads(
PASYNC_INFO pInfo);
NTSTATUS
AsyncDetectCompletionRoutine(
IN PDEVICE_OBJECT DeviceObject,
IN PIRP Irp,
IN PASYNC_INFO pInfo)
/*++
This is the IO Completion routine for ReadFrame.
--*/
{
NTSTATUS status;
PASYNC_FRAME pFrame;
PUCHAR frameStart;
DbgTracef(-1,("Entering AsyncDetectCompletionRoutine\n"));
status = Irp->IoStatus.Status;
pInfo->BytesRead = (ULONG)Irp->IoStatus.Information;
IoFreeIrp(Irp);
pFrame=pInfo->AsyncFrame;
DbgTracef(2,("DET PortState = %u for Info 0x%.8x\n", pInfo->PortState, pInfo));
//
// check if this port is closing down or already closed
//
if (pInfo->PortState == PORT_CLOSING ||
pInfo->PortState == PORT_CLOSED) {
if (pInfo->PortState == PORT_CLOSED) {
DbgTracef(-2,("ASYNC: Port closed - but still reading on it!\n"));
}
//
// Acknowledge that the port is closed
//
KeSetEvent(
&pInfo->ClosingEvent, // Event
1, // Priority
(BOOLEAN)FALSE); // Wait (does not follow)
//
// Ok, if this happens, we are shutting down. Stop
// posting reads. Don't make it try to deallocate the irp!
//
return(STATUS_MORE_PROCESSING_REQUIRED);
}
//
// If the port is close and we are still posting reads, something
// is seriously wrong here!
//
if (pInfo->PortState == PORT_CLOSED) {
DbgTracef(-2, ("ASYNC: !!Whoa, I'm reading bytes on a dead port!!\n"));
}
//
// Send off a irp to check comm status
//
AsyncCheckCommStatus(pInfo);
switch (status) {
case STATUS_SUCCESS:
//
// Look at the first byte and see if we can
// detect the framing.
//
frameStart=pFrame->Frame + PPP_PADDING;
//
// NOTE: New RAS framing clients come in with 0x02 not 0x01
//
if (frameStart[0] == SYN && (frameStart[1]==0x01 || frameStart[1] == 0x02)) {
ULONG bytesWanted;
PUCHAR frameStart2;
pInfo->SetLinkInfo.SendFramingBits =
pInfo->SetLinkInfo.RecvFramingBits = RAS_FRAMING;
DbgTracef(-1,("ASYNC: RAS framing detected\n"));
frameStart2=pFrame->Frame+10;
//
// Adjust buffer for old RAS read
//
ASYNC_MOVE_MEMORY(
frameStart2,
frameStart,
6);
frameStart=frameStart2;
bytesWanted=(frameStart[2]*256)+(frameStart[3]);
if (bytesWanted > (ULONG)(max( pInfo->Adapter->MaxFrameSize, DEFAULT_EXPANDED_PPP_MAX_FRAME_SIZE ))) {
DbgTracef(-1,("---ASYNC: Frame too large -- size: %d!\n", bytesWanted));
//
// set frame start to non-SYN character
//
*frameStart = 0;
pInfo->BytesRead=0;
pInfo->BytesWanted=6;
//
// break added to fix problem where frame has length
// greater than max frame size. This will send us back
// to detect the next frame! Added 10/31/95 by TonyBe.
//
break;
}
// if this is the first we posted, post another to get
// rest of frame.
if (pInfo->BytesRead == 6) {
pInfo->BytesRead=6;
pInfo->BytesWanted=bytesWanted +
// SYN+SOH+LEN+ETX+CRC
1 + 1 + 2 + 1 + 2 -
6;
DbgTracef(2,("---Posting second read for %d bytes\n",pInfo->BytesWanted));
}
} else
//
// It turns out that NetManage sends the flag byte at the
// end always. This means that their first frame is wrong.
// Anyway, this throws off the detect routine. So, we
// will be robust and accept frames without the FLAG_BYTE.
//
if ((frameStart[0] == PPP_FLAG_BYTE && frameStart[1]==0xFF) ||
(frameStart[0] == 0xFF && frameStart[1]==PPP_ESC_BYTE)) {
pInfo->SetLinkInfo.SendFramingBits =
pInfo->SetLinkInfo.RecvFramingBits = PPP_FRAMING;
pInfo->SetLinkInfo.SendACCM =
AsyncInfo->ExtendedACCM[0] = 0xFFFFFFFF;
DbgTracef(-1,("ASYNC: PPP framing detected\n"));
}
else {
//
// Read again!
//
DbgTracef(-1,("ASYNC: No framing detected yet\n"));
DbgTracef(-1,("ASYNC: Got %.2x %.2x %.2x %.2x %.2x %.2x\n",
frameStart[0],
frameStart[1],
frameStart[2],
frameStart[3],
frameStart[4],
frameStart[5]));
break;
}
//
// set framing mode active
//
pInfo->PortState = PORT_FRAMING;
//
// Send off the worker thread to start reading frames
// off this port - we want to be at passive level otherwise
// it don't work.
//
ExInitializeWorkItem(&(pInfo->WorkItem),
(PWORKER_THREAD_ROUTINE)AsyncStartReads,
pInfo);
ExQueueWorkItem(&(pInfo->WorkItem), DelayedWorkQueue);
return(STATUS_MORE_PROCESSING_REQUIRED);
case STATUS_TIMEOUT:
DbgTracef(-1,("---ASYNC: detect Status %x%0.8x on read\n", status));
break;
case STATUS_CANCELLED:
case STATUS_PORT_DISCONNECTED:
default:
return(STATUS_MORE_PROCESSING_REQUIRED);
}
//
// Wipe out rest of this buffer
//
SerialFlushReads(pInfo);
KeClearEvent(&pInfo->DetectEvent);
//
// Here we are at the end of processing this IRP so we go
// ahead and post another read from the serial port.
//
// this is done on a worker since we run out of stack otherwise
//
ExInitializeWorkItem(&(pInfo->WorkItem),
(PWORKER_THREAD_ROUTINE) AsyncDetectRead,
pInfo);
ExQueueWorkItem(&(pInfo->WorkItem), DelayedWorkQueue);
// We return STATUS_MORE_PROCESSING_REQUIRED so that the
// IoCompletionRoutine will stop working on the IRP.
//
return(STATUS_MORE_PROCESSING_REQUIRED);
}
NTSTATUS
AsyncDetectRead(
IN PASYNC_INFO pInfo)
/*++
--*/
{
NTSTATUS status;
PIRP irp;
PDEVICE_OBJECT deviceObject=pInfo->DeviceObject;
PFILE_OBJECT fileObject=pInfo->FileObject;
PIO_STACK_LOCATION irpSp;
PASYNC_FRAME pFrame;
PASYNC_ADAPTER pAdapter=pInfo->Adapter;
DbgTracef(-1,("Entering AsyncDetectRead\n"));
do {
if (pInfo->PortState == PORT_CLOSING ||
pInfo->PortState == PORT_CLOSED) {
status = STATUS_SUCCESS;
break;
}
// get ptr to first frame in list...
pFrame=pInfo->AsyncFrame;
irp =
IoAllocateIrp(pInfo->DeviceObject->StackSize, (BOOLEAN)FALSE);
// Setup this irp with defaults
AsyncSetupIrp(pFrame, irp);
irp->AssociatedIrp.SystemBuffer =
irp->UserBuffer =
pFrame->Frame + PPP_PADDING;
//
// Get a pointer to the stack location for the first driver. This will be
// used to pass the original function codes and parameters.
//
irpSp = IoGetNextIrpStackLocation(irp);
irpSp->MajorFunction = IRP_MJ_READ;
irpSp->FileObject = fileObject;
if (fileObject->Flags & FO_WRITE_THROUGH) {
irpSp->Flags = SL_WRITE_THROUGH;
}
//
// If this write operation is to be performed without any caching, set the
// appropriate flag in the IRP so no caching is performed.
//
irp->Flags |= IRP_READ_OPERATION;
if (fileObject->Flags & FO_NO_INTERMEDIATE_BUFFERING) {
irp->Flags |= IRP_NOCACHE;
}
//
// Copy the caller's parameters to the service-specific portion of the
// IRP.
//
irpSp->Parameters.Read.Length = 6; // from frame...
irpSp->Parameters.Read.Key = 0; // we don't use a key
irpSp->Parameters.Read.ByteOffset = fileObject->CurrentByteOffset;
IoSetCompletionRoutine(
irp, // irp to use
AsyncDetectCompletionRoutine, // routine to call when irp is done
pInfo, // context to pass routine
TRUE, // call on success
TRUE, // call on error
TRUE); // call on cancel
//
// We DO NOT insert the packet at the head of the IRP list for the thread.
// because we do NOT really have an IoCompletionRoutine that does
// anything with the thread.
//
//
// Now simply invoke the driver at its dispatch entry with the IRP.
//
status = IoCallDriver(deviceObject, irp);
} while (FALSE);
KeSetEvent(&pInfo->DetectEvent,
1,
FALSE);
return(status);
}