Chris Cant - Writing Windows WDM Device Drivers

Buffer = NULL;

BufferSize = 0;

}

break;

///////Get Buffer Size as ULONG

case IOCTL_WDM1_GET_BUFFER_SIZE:

if (OutputLength

else {

BytesTxd = sizeof(ULONG);

RtlCopyMemory(Irp->AssociatedIrp.SystemBuffer,&BufferSize,sizeof(ULONG));

}

break;

///////Get Buffer

case IOCTL_WDM1_GET_BUFFER:

if (OutputLength>BufferSize) status = STATUS_INVALID_PARAMETER;

else {

BytesTxd = OutputLength;

RtlCopyMemory(Irp->AssociatedIrp.SystemBuffer,Buffer,BytesTxd);

}

break;

///////Invalid request

default:

status = STATUS_INVALID_DEVICE_REQUEST;

}

// Release shared buffer

KeReleaseSpinlock(&BufferLock,irql);

DebugPrint("DeviceIoControl: %d bytes written", (int)BytesTxd);

// Complete IRP

return CompleteIrp(Irp,status.BytesTxd);

}

///////////////////////////////////////////////////////////////////////

//Wdm1SystemControl:

//

//Description:

//Handle IRP_MJ_SYSTEM_C0NTROL requests

//

//Arguments:

//Pointer to our FDO

//Pointer to the IRP

//Various minor parameters

//IrpStack->Parameters.WMI.xxx has WMI parameters

//

//Return Value:

//This function returns STATUS_XXX

NTSTATUS WdmlSystemControl(IN PDEVICE_OBJECT fdo, IN PIRP Irp) {

DebugPrintMsg("SystemControl");

// Just pass to lower driver

IoSkipCurrentIrpStackLocation(Irp);

PWDM1_DEVICE_EXTENSION dx = (PWDM1_DEVICE_EXTENSION)fdo->DeviceExtension;

return IoCallDriver(dx->NextStackDevice, Irp);

}

///////////////////////////////////////////////////////////////////////

//Wdm1Cleanup:

//

//Description:

//Handle IRP_MJ_CLEANUP requests

//Cancel queued IRPs which match given FileObject

//

//Arguments:

//Pointer to our FDO

//Pointer to the IRP

//IrpStack->FileObject has handle to file

//

//Return Value:

//This function returns STATUS_XXX

//Not needed for Wdm1

///////////////////////////////////////////////////////////////////////

//CompleteIrp:Sets IoStatus and completes the IRP

NTSTATUS CompleteIrp(PIRP Irp, NTSTATUS status, ULONG info) {

Irp->IoStatus.Status = status;

Irp->IoStatus.Information = info;

IoCompleteRequest(Irp,IO_NO_INCREMENT);

return status;

}

///////////////////////////////////////////////////////////////////////

Listing 4.11 Wdm1.rc

//Microsoft Developer Studio generated resource script.

//

#include "resource.h"

#define APSTUDIO_READONLY_SYMBOLS

///////////////////////////////////////////////////////////////////////

//

// Generated from the TEXTINCLUDE 2 resource.

//

#include "afxres.h"

///////////////////////////////////////////////////////////////////////

#undef APSTUDIO_READONLY_SYMBOLS

///////////////////////////////////////////////////////////////////////

// English (U.S.) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)

#ifdef _WIN32

LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US

#pragma code_page(1252)

#endif //_WIN32

#ifndef _MAC

///////////////////////////////////////////////////////////////////////

//

// Version

//

VS_VERSION_INFO VERSIONINFO

FILEVERSION 1,0,5,0

PRODUCTVERSION 1,0,0,0

FILEFLAGSMASK 0x3fL

#ifdef _DEBUG

FILEFLAGS 0x1L

#else

FILEFLAGS 0x0L

#endif

FILEOS 0x4L

FILETYPE 0x2L

FILESUBTYPE 0x0L

BEGIN

BLOCK "StringFileInfo"

BEGIN

BLOCK "080904b0"

BEGIN

VALUE "Comments", "Chris Cant\0"

VALUE "CompanyName", "PHD Computer Consultants Ltd\0"

VALUE "FileDescription", "Wdm1\0"

VALUE "FileVersion", "1, 0, 5, 0\0"

VALUE "InternalName", "Wdm1 driver\0"

VALUE "LegalCopyright", "Copyright © 1998,1999 PHD Computer Consultants Ltd\0"

VALUE "OriginalFilename", "Wdm1.sys\0"

VALUE "ProductName", "WDM Book\0"

VALUE "ProductVersion", "1, 0, 0, 0\0"

END

END

BLOCK "VarFileInfo"

BEGIN

VALUE "Translation", 0x809, 1200

END

END

#endif // !_MAC

#endif // English (U.S.) resources

///////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////

// English (U.K.) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENG)

#ifdef _WIN32

LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_UK

#pragma codepage(1252)

#endif //_WIN32

#ifdef APSTUDIO_INVOKED

///////////////////////////////////////////////////////////////////////

//

// TEXTINCLUDE

//

1 TEXTINCLUDE DISCARDABLE

BEGIN

"resource.h\0"

END

2 TEXTINCLUDE DISCARDABLE

BEGIN

"#include ""afxres.h""\r\n" "\0"

END

3 TEXTINCLUDE DISCARDABLE

BEGIN

"\r\n" "\0"

END

#endif // APSTUDIO_INVOKED

#endif // English (U.K.) resources

///////////////////////////////////////////////////////////////////////

#ifndef APSTUDIO_INVOKED

///////////////////////////////////////////////////////////////////////

//

// Generated from the TEXTINCLUDE 3 resource.

//

///////////////////////////////////////////////////////////////////////

#endif // not APSTUDIO_INVOKED

Listing 4.12 Ioctl.h

//DeviceIoControl IOCTL codes supported by Wdm1

#define IOCTL_WDM1_ZERO_BUFFER CTL_CODE(\

FILE_DEVICE_UNKNOWN,\