Windows NT Driver >> Assembly
Cancel IRP
參考資訊:
1. Four-F
2. Source Code
3. canceling-irps
有處理Irp就會有Cancel Irp的時候,Cancel Irp本身就是一個很複雜的課題,司徒在這一篇教學不會做深入探討,有興趣的使用者可以參考上面的參考資訊,取而代之的,司徒只是點出,在處理Irp時,使用者要意識到該Irp可能已經被Cancel掉了,作法上,也是可以切割成很多時期,如:Irp處理前,Irp處裡中,Irp處裡後,因此,在設計驅動程式時,對於Cancel機制有必要嚴謹看待,因為,BSOD常常就是這樣發生了,不過司徒在此僅針對Irp處裡前,作簡單判斷,是否User Application已經Cancel這個Irp,如果沒有被Cancel,則Complete Irp,相反地,如果被Cancel,則Cancel Irp,Cancel作法如下:
1. CancelRoutine(NULL)
2. IoCompleteRequest(STATUS_CANCELLED)
main.asm
.386p .model flat, stdcall option casemap:none include c:\masm32\include\w2k\ntstatus.inc include c:\masm32\include\w2k\ntddk.inc include c:\masm32\include\w2k\ntoskrnl.inc include c:\masm32\include\w2k\ntddkbd.inc include c:\masm32\Macros\Strings.mac includelib c:\masm32\lib\wxp\i386\ntoskrnl.lib public DriverEntry OurDeviceExtension struct pNextDev PDEVICE_OBJECT ? stQueue LIST_ENTRY <> stDPC KDPC <> stTime KTIMER <> OurDeviceExtension ends IOCTL_QUEUE equ CTL_CODE(FILE_DEVICE_UNKNOWN, 800h, METHOD_BUFFERED, FILE_ANY_ACCESS) IOCTL_PROCESS equ CTL_CODE(FILE_DEVICE_UNKNOWN, 801h, METHOD_BUFFERED, FILE_ANY_ACCESS) .const DEV_NAME word "\","D","e","v","i","c","e","\","M","y","D","r","i","v","e","r",0 SYM_NAME word "\","D","o","s","D","e","v","i","c","e","s","\","M","y","D","r","i","v","e","r",0 MSG_QUEUE byte "IOCTL_QUEUE",0 MSG_PROCESS byte "IOCTL_PROCESS",0 .code OnTimer proc uses ebx pDpc:PKDPC, pContext:PVOID, pArg1:PVOID, PArg2:PVOID mov eax, pContext mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension lea eax, (OurDeviceExtension PTR [eax]).stQueue IsListEmpty eax .if eax == TRUE mov eax, pContext mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension invoke KeCancelTimer, addr (OurDeviceExtension PTR [eax]).stTime invoke DbgPrint, $CTA0("Finish") .else mov eax, pContext mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension lea eax, (OurDeviceExtension PTR [eax]).stQueue RemoveHeadList eax ; CONTAINING_RECORD sub eax, _IRP.Tail.Overlay.ListEntry mov bl, (_IRP PTR [eax]).Cancel .if bl != TRUE mov (_IRP PTR [eax]).IoStatus.Status, STATUS_SUCCESS push 0 pop (_IRP PTR [eax]).IoStatus.Information fastcall IofCompleteRequest, eax, IO_NO_INCREMENT mov eax, STATUS_SUCCESS invoke DbgPrint, $CTA0("Complete Irp") .else mov (_IRP PTR [eax]).CancelRoutine, NULL mov (_IRP PTR [eax]).IoStatus.Status, STATUS_CANCELLED push 0 pop (_IRP PTR [eax]).IoStatus.Information fastcall IofCompleteRequest, eax, IO_NO_INCREMENT invoke DbgPrint, $CTA0("Cancel Irp") .endif .endif ret OnTimer endp IrpOpenClose proc pDevObj:PDEVICE_OBJECT, pIrp:PIRP IoGetCurrentIrpStackLocation pIrp movzx eax, (IO_STACK_LOCATION PTR [eax]).MajorFunction .if eax == IRP_MJ_CREATE invoke DbgPrint, $CTA0("IRP_MJ_CREATE") .elseif eax == IRP_MJ_CLOSE invoke DbgPrint, $CTA0("IRP_MJ_CLOSE") .endif mov eax, pIrp and (_IRP PTR [eax]).IoStatus.Information, 0 mov (_IRP PTR [eax]).IoStatus.Status, STATUS_SUCCESS fastcall IofCompleteRequest, pIrp, IO_NO_INCREMENT mov eax, STATUS_SUCCESS ret IrpOpenClose endp IrpIOCTL proc uses ebx ecx pOurDevice:PDEVICE_OBJECT, pIrp:PIRP local pdx:PTR Dev_Ext local stTimePeriod:LARGE_INTEGER mov eax, pOurDevice push (DEVICE_OBJECT PTR [eax]).DeviceExtension pop pdx IoGetCurrentIrpStackLocation pIrp mov eax, (IO_STACK_LOCATION PTR [eax]).Parameters.DeviceIoControl.IoControlCode .if eax == IOCTL_QUEUE invoke DbgPrint, offset MSG_QUEUE mov ebx, pdx lea ebx, (OurDeviceExtension PTR [ebx]).stQueue mov ecx, pIrp lea ecx, (_IRP PTR [ecx]).Tail.Overlay.ListEntry InsertHeadList ebx, ecx IoMarkIrpPending pIrp mov eax, STATUS_PENDING ret .elseif eax == IOCTL_PROCESS invoke DbgPrint, offset MSG_PROCESS or stTimePeriod.HighPart, -1 mov stTimePeriod.LowPart, -10000000 mov ebx, pdx invoke KeSetTimerEx, addr (OurDeviceExtension PTR [ebx]).stTime, stTimePeriod.LowPart, stTimePeriod.HighPart, 1000, addr (OurDeviceExtension PTR [ebx]).stDPC .endif mov eax, pIrp mov (_IRP PTR [eax]).IoStatus.Status, STATUS_SUCCESS and (_IRP PTR [eax]).IoStatus.Information, 0 fastcall IofCompleteRequest, pIrp, IO_NO_INCREMENT mov eax, STATUS_SUCCESS ret IrpIOCTL endp Unload proc pOurDriver:PDRIVER_OBJECT local szSymName:UNICODE_STRING invoke RtlInitUnicodeString, addr szSymName, offset SYM_NAME invoke IoDeleteSymbolicLink, addr szSymName mov eax, pOurDriver invoke IoDeleteDevice, (DRIVER_OBJECT PTR [eax]).DeviceObject ret Unload endp DriverEntry proc pOurDriver:PDRIVER_OBJECT, pOurRegistry:PUNICODE_STRING local pOurDevice:PDEVICE_OBJECT local suDevName:UNICODE_STRING local szSymName:UNICODE_STRING mov eax, pOurDriver mov (DRIVER_OBJECT PTR [eax]).MajorFunction[IRP_MJ_CREATE * (sizeof PVOID)], offset IrpOpenClose mov (DRIVER_OBJECT PTR [eax]).MajorFunction[IRP_MJ_CLOSE * (sizeof PVOID)], offset IrpOpenClose mov (DRIVER_OBJECT PTR [eax]).MajorFunction[IRP_MJ_DEVICE_CONTROL * (sizeof PVOID)], offset IrpIOCTL mov (DRIVER_OBJECT PTR [eax]).DriverUnload, offset Unload invoke RtlInitUnicodeString, addr suDevName, offset DEV_NAME invoke RtlInitUnicodeString, addr szSymName, offset SYM_NAME invoke IoCreateDevice, pOurDriver, sizeof OurDeviceExtension, addr suDevName, FILE_DEVICE_UNKNOWN, 0, FALSE, addr pOurDevice .if eax == STATUS_SUCCESS mov eax, pOurDevice or (DEVICE_OBJECT PTR [eax]).Flags, DO_BUFFERED_IO and (DEVICE_OBJECT PTR [eax]).Flags, not DO_DEVICE_INITIALIZING mov eax, pOurDevice mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension lea eax, (OurDeviceExtension PTR [eax]).stQueue InitializeListHead eax mov eax, pOurDevice mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension invoke KeInitializeTimer, addr (OurDeviceExtension ptr [eax]).stTime mov eax, pOurDevice mov eax, (DEVICE_OBJECT PTR [eax]).DeviceExtension invoke KeInitializeDpc, addr (OurDeviceExtension ptr [eax]).stDPC, offset OnTimer, pOurDevice invoke IoCreateSymbolicLink, addr szSymName, addr suDevName .endif ret DriverEntry endp end DriverEntry .end
DriverEntry()初始List以及DPC Timer,DPC Timer用來定期確認List是否還有資料需要處理,當然,使用Thread檢查或許更恰當些
IrpIOCTL()IOCTL_QUEUE代表該IOCTL會被Queue起來,稍後處理,而當收到IOCTL_PROCESS時,則啟動DPC Timer開始處理那些被Queue起來的Irp
OnTimer()處理Queue裡面的Irp,在處理前,先判斷該Irp是否已經被Cancel了
app.asm
.386p .model flat, stdcall option casemap:none include c:\masm32\include\windows.inc include c:\masm32\include\masm32.inc include c:\masm32\include\user32.inc include c:\masm32\include\msvcrt.inc include c:\masm32\include\kernel32.inc include c:\masm32\include\w2k\ntddkbd.inc include c:\masm32\Macros\Strings.mac includelib c:\masm32\lib\user32.lib includelib c:\masm32\lib\masm32.lib includelib c:\masm32\lib\msvcrt.lib includelib c:\masm32\lib\kernel32.lib IOCTL_QUEUE equ CTL_CODE(FILE_DEVICE_UNKNOWN, 800h, METHOD_BUFFERED, FILE_ANY_ACCESS) IOCTL_PROCESS equ CTL_CODE(FILE_DEVICE_UNKNOWN, 801h, METHOD_BUFFERED, FILE_ANY_ACCESS) .const DEV_NAME db "\\.\MyDriver",0 .data? cnt dd ? hFile dd ? dwRet dd ? event dd 3 dup(?) ov OVERLAPPED <?> .code start: invoke CreateFile, offset DEV_NAME, GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_FLAG_OVERLAPPED or FILE_ATTRIBUTE_NORMAL, 0 .if eax == INVALID_HANDLE_VALUE invoke crt_printf, $CTA0("failed to open mydriver\n") invoke ExitProcess, -1 .endif mov hFile, eax invoke crt_memset, offset ov, 0, sizeof OVERLAPPED mov cnt, 3 .while cnt > 0 invoke CreateEvent, NULL, TRUE, FALSE, NULL push eax pop ov.hEvent mov ecx, cnt mov edi, offset event mov [edi + ecx * 4], eax invoke crt_printf, $CTA0("queue event\n") invoke DeviceIoControl, hFile, IOCTL_QUEUE, NULL, 0, NULL, 0, offset dwRet, offset ov invoke CloseHandle, ov.hEvent sub cnt, 1 .endw invoke crt_printf, $CTA0("process all of events\n") invoke DeviceIoControl, hFile, IOCTL_PROCESS, NULL, 0, NULL, 0, offset dwRet, NULL invoke Sleep, 1000 invoke CancelIo, hFile mov cnt, 3 .while cnt > 0 mov ecx, cnt mov edi, offset event mov eax, [edi + ecx * 4] push eax pop ov.hEvent invoke WaitForSingleObject, ov.hEvent, INFINITE invoke CloseHandle, ov.hEvent invoke crt_printf, $CTA0("wait complete\n") sub cnt, 1 .endw invoke CloseHandle, hFile invoke ExitProcess, 0 end start
結果