C++ KeLowerIrql函数代码示例

//在这里InlineHook
VOID monitor2_inlineHookObReferenceObjectByHandle()
{

	//赋值前面定义的数组
	KIRQL Irql;

	//保存函数前五个字节内容
	RtlCopyMemory(OldObAddress,(PBYTE)ObReferenceObjectByHandle,5);
	//保存新函数五个字节之后偏移
	*(PULONG)(NewObAddress+1)=(ULONG)NewObReferenceObjectByHandle-((ULONG)ObReferenceObjectByHandle+5);

	//开始inline hook
	//关闭内存写保护
	UnProtected();

	//提升IRQL中断级
	Irql=KeRaiseIrqlToDpcLevel();
	//函数开头五个字节写JMP 
	RtlCopyMemory((PBYTE)ObReferenceObjectByHandle,NewObAddress,5);
	//恢复Irql
	KeLowerIrql(Irql);

	//开启内存写保护
	Protected();
}

/* KphReleaseProcessorLock
 *
 * Allows threads to execute on other processors and restores the IRQL.
 *
 * ProcessorLock: A processor lock structure that is present in
 * non-paged memory.
 *
 * Comments:
 * Here is how the processor lock is released:
 *  1. Sets the signal to release the processors. The DPCs that are
 *     currently waiting for the signal will return and decrement
 *     the acquired processors counter.
 *  2. Waits for the acquired processors counter to become zero.
 *  3. Restores the old IRQL. This will always be APC_LEVEL due to
 *     the mutex.
 *  4. Frees the storage allocated for the DPCs.
 *  5. Releases the processor lock mutex. This will restore the IRQL
 *     back to normal.
 * Thread safety: Full
 * IRQL: DISPATCH_LEVEL
 */
VOID KphReleaseProcessorLock(
    __inout PKPH_PROCESSOR_LOCK ProcessorLock
)
{
    if (!ProcessorLock->Acquired)
        return;

    /* Signal for the acquired processors to be released. */
    InterlockedExchange(&ProcessorLock->ReleaseSignal, 1);

    /* Spinwait for all acquired processors to be released. */
    KphSpinUntilEqual(&ProcessorLock->AcquiredProcessors, 0);

    dprintf("KphReleaseProcessorLock: All processors released.\n");

    /* Restore the old IRQL (should always be APC_LEVEL due to the
     * fast mutex). */
    KeLowerIrql(ProcessorLock->OldIrql);

    /* Free the DPCs if necessary. */
    if (ProcessorLock->Dpcs != NULL)
    {
        ExFreePoolWithTag(ProcessorLock->Dpcs, TAG_SYNC_DPC);
        ProcessorLock->Dpcs = NULL;
    }

    ProcessorLock->Acquired = FALSE;

    /* Release the processor lock guarded lock. This will restore the
     * IRQL back to what it was before the processor lock was
     * acquired.
     */
    KphReleaseGuardedLock(&ProcessorLock->Lock);
}

VOID
XenPci_HighSync(PXENPCI_HIGHSYNC_FUNCTION function0, PXENPCI_HIGHSYNC_FUNCTION functionN, PVOID context)
{
  ULONG ActiveProcessorCount;
  ULONG i;
  highsync_info_t *highsync_info;
  KIRQL old_irql;

  UNREFERENCED_PARAMETER(context);
  FUNCTION_ENTER();

  highsync_info = ExAllocatePoolWithTag(NonPagedPool, sizeof(highsync_info_t), XENPCI_POOL_TAG);
  RtlZeroMemory(highsync_info, sizeof(highsync_info_t));
  KeInitializeEvent(&highsync_info->highsync_complete_event, SynchronizationEvent, FALSE);
  highsync_info->function0 = function0;
  highsync_info->functionN = functionN;
  highsync_info->context = context;
  highsync_info->sync_level = HIGH_LEVEL;

#if (NTDDI_VERSION >= NTDDI_WINXP)
  ActiveProcessorCount = (ULONG)KeNumberProcessors;
#else
  ActiveProcessorCount = (ULONG)*KeNumberProcessors;
#endif

  /* Go to HIGH_LEVEL to prevent any races with Dpc's on the current processor */
  KeRaiseIrql(highsync_info->sync_level, &old_irql);

  highsync_info->do_spin = TRUE;
  for (i = 0; i < ActiveProcessorCount; i++)
  {
    if (i == 0)
      KeInitializeDpc(&highsync_info->dpcs[i], XenPci_HighSyncCallFunction0, highsync_info);
    else
      KeInitializeDpc(&highsync_info->dpcs[i], XenPci_HighSyncCallFunctionN, highsync_info);
    KeSetTargetProcessorDpc(&highsync_info->dpcs[i], (CCHAR)i);
    KeSetImportanceDpc(&highsync_info->dpcs[i], HighImportance);
    KdPrint((__DRIVER_NAME "     queuing Dpc for CPU %d\n", i));
    KeInsertQueueDpc(&highsync_info->dpcs[i], NULL, NULL);
  }
  KdPrint((__DRIVER_NAME "     All Dpc's queued\n"));

  KeMemoryBarrier();
  KeLowerIrql(old_irql);

  KdPrint((__DRIVER_NAME "     Waiting for highsync_complete_event\n"));
  KeWaitForSingleObject(&highsync_info->highsync_complete_event, Executive, KernelMode, FALSE, NULL);
#if (NTDDI_VERSION >= NTDDI_WINXP)
  KeFlushQueuedDpcs();
#else
  {
    /* just wait 1 second until all DPC's finish - not ideal but it's only for W2K */
    LARGE_INTEGER interval;
    interval.QuadPart = -1 * 1000 * 1000 * 10; /* 1 second */
    KeDelayExecutionThread(KernelMode, FALSE, &interval);
  }
#endif
  ExFreePoolWithTag(highsync_info, XENPCI_POOL_TAG);
  FUNCTION_EXIT();
}

_Use_decl_annotations_ bool __stdcall VmmVmExitHandler(VmmInitialStack *stack) {
  // Save guest's context and raise IRQL as quick as possible
  const auto guest_irql = KeGetCurrentIrql();
  const auto guest_cr8 = IsX64() ? __readcr8() : 0;
  if (guest_irql < DISPATCH_LEVEL) {
    KeRaiseIrqlToDpcLevel();
  }
  NT_ASSERT(stack->reserved == MAXULONG_PTR);

  // Capture the current guest state
  GuestContext guest_context = {stack,
                                UtilVmRead(VmcsField::kGuestRflags),
                                UtilVmRead(VmcsField::kGuestRip),
                                guest_cr8,
                                guest_irql,
                                true};
  guest_context.gp_regs->sp = UtilVmRead(VmcsField::kGuestRsp);

  // Dispatch the current VM-exit event
  VmmpHandleVmExit(&guest_context);

  // Restore guest's context
  if (guest_context.irql < DISPATCH_LEVEL) {
    KeLowerIrql(guest_context.irql);
  }

  // Apply possibly updated CR8 by the handler
  if (IsX64()) {
    __writecr8(guest_context.cr8);
  }
  return guest_context.vm_continue;
}

/*
 * @implemented
 */
VOID
NTAPI
KeGenericCallDpc(IN PKDEFERRED_ROUTINE Routine,
                 IN PVOID Context)
{
    ULONG Barrier = KeNumberProcessors;
    KIRQL OldIrql;
    DEFERRED_REVERSE_BARRIER ReverseBarrier;
    ASSERT(KeGetCurrentIrql () < DISPATCH_LEVEL);

    //
    // The barrier is the number of processors, each processor will decrement it
    // by one, so when all processors have run the DPC, the barrier reaches zero
    //
    ReverseBarrier.Barrier = Barrier;
    ReverseBarrier.TotalProcessors = Barrier;

    //
    // But we don't need the barrier on UP, since we can simply call the routine
    // directly while at DISPATCH_LEVEL and not worry about anything else
    //
    KeRaiseIrql(DISPATCH_LEVEL, &OldIrql);
    Routine(&KeGetCurrentPrcb()->CallDpc, Context, &Barrier, &ReverseBarrier);
    KeLowerIrql(OldIrql);
}

static
VOID
NTAPI
AcquireMutexThread(
    PVOID Parameter)
{
    PTHREAD_DATA ThreadData = Parameter;
    KIRQL Irql;
    BOOLEAN Ret = FALSE;
    NTSTATUS Status;

    KeRaiseIrql(ThreadData->Irql, &Irql);

    if (ThreadData->Try)
    {
        Ret = ThreadData->TryAcquire(ThreadData->Mutex);
        ok_eq_bool(Ret, ThreadData->RetExpected);
    }
    else
        ThreadData->Acquire(ThreadData->Mutex);

    ok_bool_false(KeSetEvent(&ThreadData->OutEvent, 0, TRUE), "KeSetEvent returned");
    Status = KeWaitForSingleObject(&ThreadData->InEvent, Executive, KernelMode, FALSE, NULL);
    ok_eq_hex(Status, STATUS_SUCCESS);

    if (!ThreadData->Try || Ret)
        ThreadData->Release(ThreadData->Mutex);

    KeLowerIrql(Irql);
}

VOID NBDestroyNeighborsForInterface(PIP_INTERFACE Interface)
{
    KIRQL OldIrql;
    PNEIGHBOR_CACHE_ENTRY *PrevNCE;
    PNEIGHBOR_CACHE_ENTRY NCE;
    ULONG i;

    KeRaiseIrql(DISPATCH_LEVEL, &OldIrql);
    for (i = 0; i <= NB_HASHMASK; i++)
    {
        TcpipAcquireSpinLockAtDpcLevel(&NeighborCache[i].Lock);
        
        for (PrevNCE = &NeighborCache[i].Cache;
             (NCE = *PrevNCE) != NULL;)
        {
            if (NCE->Interface == Interface)
            {
                /* Unlink and destroy the NCE */
                *PrevNCE = NCE->Next;

                NBFlushPacketQueue(NCE, NDIS_STATUS_REQUEST_ABORTED);
                ExFreePoolWithTag(NCE, NCE_TAG);

                continue;
            }
            else
            {
                PrevNCE = &NCE->Next;
            }
        }
        
        TcpipReleaseSpinLockFromDpcLevel(&NeighborCache[i].Lock);
    }
    KeLowerIrql(OldIrql);
}

NTSTATUS	ResponsePortAskWorkerForIndicateupPacket(PDEVICE_OBJECT  DeviceObject, PVOID	pContext)
{
	PASKUserWorkItemContext	pPAskContext=NULL;
	NTSTATUS		status	=	STATUS_SUCCESS;
	PAcceptedPort	pIndicateContext=NULL;
	KIRQL			CIrql=0, CIrql2=0;
	//__asm int 3
	CIrql	=	KeGetCurrentIrql();
	pPAskContext	=	(PASKUserWorkItemContext)pContext;
	if (pPAskContext==NULL)
	{
		return status;
	}
	pIndicateContext	=	(PAcceptedPort)pPAskContext->pContext;
	IoFreeWorkItem(pPAskContext->pWorkItem);
	kfree(pPAskContext);
	
	//自定义向上提交一份
	status = BypassTcpipArpRcv((NDIS_HANDLE)pIndicateContext->ProtocolBindingContext, (NDIS_HANDLE)pIndicateContext->MacReceiveContext, pIndicateContext->HeaderBuffer, pIndicateContext->HeaderBufferSize,\
		pIndicateContext->LookAheadBuffer, pIndicateContext->LookAheadBufferSize, pIndicateContext->LookAheadBufferSize);
	if (KeGetCurrentIrql()>CIrql)
	{
		KeLowerIrql(CIrql);
	}
	if (KeGetCurrentIrql()<CIrql)
	{
		KeRaiseIrql(CIrql, &CIrql2);
	}
	kfree(pIndicateContext);
	return status;

}

VOID
NTAPI
PspSystemThreadStartup(IN PKSTART_ROUTINE StartRoutine,
                       IN PVOID StartContext)
{
    PETHREAD Thread;
    PSTRACE(PS_THREAD_DEBUG,
            "StartRoutine: %p StartContext: %p\n", StartRoutine, StartContext);

    /* Unlock the dispatcher Database */
    KeLowerIrql(PASSIVE_LEVEL);
    Thread = PsGetCurrentThread();

    /* Make sure the thread isn't gone */
    _SEH2_TRY
    {
        if (!(Thread->Terminated) && !(Thread->DeadThread))
        {
            /* Call the Start Routine */
            StartRoutine(StartContext);
        }
    }
    _SEH2_EXCEPT(PspUnhandledExceptionInSystemThread(_SEH2_GetExceptionInformation()))
    {
        /* Bugcheck if we got here */
        KeBugCheck(KMODE_EXCEPTION_NOT_HANDLED);
    }
    _SEH2_END;

    /* Exit the thread */
    PspTerminateThreadByPointer(Thread, STATUS_SUCCESS, TRUE);
}

VOID
NTAPI
VdmEndExecution(IN PKTRAP_FRAME TrapFrame,
                IN PVDM_TIB VdmTib)
{
    KIRQL OldIrql;
    CONTEXT Context;
    PAGED_CODE();

    /* Sanity check */
    ASSERT((TrapFrame->EFlags & EFLAGS_V86_MASK) ||
           (TrapFrame->SegCs != (KGDT_R3_CODE | RPL_MASK)));

    /* Raise to APC_LEVEL */
    KeRaiseIrql(APC_LEVEL, &OldIrql);

    /* Set success */
    VdmTib->MonitorContext.Eax = STATUS_SUCCESS;

    /* Make a copy of the monitor context */
    Context = VdmTib->MonitorContext;
    
    /* Check if V86 mode was enabled or the trap was edited */
    if ((Context.EFlags & EFLAGS_V86_MASK) || (Context.SegCs & FRAME_EDITED))
    {
        /* Switch contexts */
        VdmSwapContext(TrapFrame, &VdmTib->VdmContext, &Context);

        /* Check if VME is supported and V86 mode was enabled */
        if ((KeI386VirtualIntExtensions) &&
            (VdmTib->VdmContext.EFlags & EFLAGS_V86_MASK))
        {
            /* Check for VIF (virtual interrupt) flag state */
            if (VdmTib->VdmContext.EFlags & EFLAGS_VIF)
            {
                /* Set real IF flag */
                VdmTib->VdmContext.EFlags |= EFLAGS_INTERRUPT_MASK;
            }
            else
            {
                /* Remove real IF flag */
                VdmTib->VdmContext.EFlags &= ~EFLAGS_INTERRUPT_MASK;
            }
            
            /* Turn off VIP and VIF */
            TrapFrame->EFlags &= ~(EFLAGS_VIP | EFLAGS_VIF);
            VdmTib->VdmContext.EFlags &= ~(EFLAGS_VIP | EFLAGS_VIF);
        }
        else
        {
            /* Set the EFLAGS based on our software copy of EFLAGS */
            VdmTib->VdmContext.EFlags = (VdmTib->VdmContext.EFlags & ~EFLAGS_INTERRUPT_MASK) |
                                        (*VdmState & EFLAGS_INTERRUPT_MASK);
        }
    }

    /* Lower IRQL and reutrn */
    KeLowerIrql(OldIrql);
}

static VOID
XenPci_HighSyncCallFunction0(
  PRKDPC Dpc,
  PVOID Context,
  PVOID SystemArgument1,
  PVOID SystemArgument2)
{
  highsync_info_t *highsync_info = Context;
  ULONG ActiveProcessorCount;
  KIRQL old_irql;
  
  UNREFERENCED_PARAMETER(Dpc);
  UNREFERENCED_PARAMETER(SystemArgument1);
  UNREFERENCED_PARAMETER(SystemArgument2);

  FUNCTION_ENTER();
#if (NTDDI_VERSION >= NTDDI_WINXP)
  ActiveProcessorCount = (ULONG)KeNumberProcessors;
#else
  ActiveProcessorCount = (ULONG)*KeNumberProcessors;
#endif
  InterlockedIncrement(&highsync_info->nr_procs_at_dispatch_level);
  if (highsync_info->sync_level > DISPATCH_LEVEL)
  {
    while (highsync_info->nr_procs_at_dispatch_level < (LONG)ActiveProcessorCount)
    {
      KeStallExecutionProcessor(1);
      KeMemoryBarrier();
    }
  }
  _disable(); //__asm cli;  
  KeRaiseIrql(highsync_info->sync_level, &old_irql);
  while (highsync_info->nr_spinning_at_sync_level < (LONG)ActiveProcessorCount - 1)
  {
    KeStallExecutionProcessor(1);
    KeMemoryBarrier();
  }
  highsync_info->function0(highsync_info->context);
  KeLowerIrql(old_irql);
  _enable(); //__asm sti;
  highsync_info->do_spin = FALSE;
  KeMemoryBarrier();  
  /* wait for all the other processors to complete spinning, just in case it matters */
  while (highsync_info->nr_spinning_at_sync_level)
  {
    KeStallExecutionProcessor(1);
    KeMemoryBarrier();
  }
  InterlockedDecrement(&highsync_info->nr_procs_at_dispatch_level);
  /* wait until nr_procs_at_dispatch_level drops to 0 indicating that nothing else requires highsync_info */
  while (highsync_info->nr_procs_at_dispatch_level)
  {
    KeStallExecutionProcessor(1);
    KeMemoryBarrier();
  }
  KeSetEvent(&highsync_info->highsync_complete_event, IO_NO_INCREMENT, FALSE);

  FUNCTION_EXIT();
}

VOID
HalCalibratePerformanceCounter (
    IN volatile PLONG Number
    )

/*++

Routine Description:

    This routine resets the performance counter value for the current
    processor to zero. The reset is done such that the resulting value
    is closely synchronized with other processors in the configuration.

Arguments:

    Number - Supplies a pointer to count of the number of processors in
    the configuration.

Return Value:

    None.

--*/

{

    KSPIN_LOCK Lock;
    KIRQL OldIrql;
    PKPRCB Prcb;

    //
    // Raise IRQL to HIGH_LEVEL, decrement the number of processors, and
    // wait until the number is zero.
    //

    KeInitializeSpinLock(&Lock);
    KeRaiseIrql(HIGH_LEVEL, &OldIrql);
    if (ExInterlockedDecrementLong(Number, &Lock) != RESULT_ZERO) {
        do {

        } while (*Number !=0);
    }

    //
    // Write the compare register, clear the count register, and zero the
    // performance counter for the current processor.
    //

    HalpWriteCompareRegisterAndClear(DEFAULT_PROFILE_COUNT);
    Prcb = KeGetCurrentPrcb();
    HalpPerformanceCounter[Prcb->Number].QuadPart = 0;

    //
    // Restore IRQL to its previous value and return.
    //

    KeLowerIrql(OldIrql);
    return;
}

NTSTATUS
NTAPI
BeepCleanup(IN PDEVICE_OBJECT DeviceObject,
            IN PIRP Irp)
{
    KIRQL OldIrql, CancelIrql;
    PKDEVICE_QUEUE_ENTRY Packet;
    PIRP CurrentIrp;

    /* Raise IRQL and acquire the cancel lock */
    KeRaiseIrql(DISPATCH_LEVEL, &OldIrql);
    IoAcquireCancelSpinLock(&CancelIrql);

    /* Get the current IRP */
    CurrentIrp = DeviceObject->CurrentIrp;
    DeviceObject->CurrentIrp = NULL;
    while (CurrentIrp)
    {
        /* Clear its cancel routine */
        (VOID)IoSetCancelRoutine(CurrentIrp, NULL);

        /* Cancel the IRP */
        CurrentIrp->IoStatus.Status = STATUS_CANCELLED;
        CurrentIrp->IoStatus.Information = 0;

        /* Release the cancel lock and complete it */
        IoReleaseCancelSpinLock(CancelIrql);
        IoCompleteRequest(CurrentIrp, IO_NO_INCREMENT);

        /* Reacquire the lock and get the next queue packet */
        IoAcquireCancelSpinLock(&CancelIrql);
        Packet = KeRemoveDeviceQueue(&DeviceObject->DeviceQueue);
        if (Packet)
        {
            /* Get the IRP */
            CurrentIrp = CONTAINING_RECORD(Packet,
                                           IRP,
                                           Tail.Overlay.DeviceQueueEntry);
        }
        else
        {
            /* No more IRPs */
            CurrentIrp = NULL;
        }
    }

    /* Release lock and go back to low IRQL */
    IoReleaseCancelSpinLock(CancelIrql);
    KeLowerIrql(OldIrql);

    /* Complete the IRP */
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    /* Stop and beep and return */
    HalMakeBeep(0);
    return STATUS_SUCCESS;
}

static VOID CfixkrsReleaseLockFilamentRegistry( 
	__in PCFIXKRP_FILAMENT_REGISTRY Registry,
	__in KIRQL OldIrql
	)
{
	KeReleaseSpinLockFromDpcLevel( &Registry->Lock );
	KeLowerIrql( OldIrql );
}

static void TestFormattedAssertionAtElevatedIrql()
{
	KIRQL OldIrql;
	KeRaiseIrql( DISPATCH_LEVEL, &OldIrql );
	CFIX_ASSERT_MESSAGE( TRUE, L"%d%s", 1, L"123" );
	CFIX_ASSERT_MESSAGE( TRUE, L"test" );
	KeLowerIrql( OldIrql );
}