KSDDKAPI BOOLEAN NTAPI KsFastMethodHandler	(	IN PFILE_OBJECT	FileObject,
		IN PKSMETHOD UNALIGNED	Method,
		IN ULONG	MethodLength,
		IN OUT PVOID UNALIGNED	Data,
		IN ULONG	DataLength,
		OUT PIO_STATUS_BLOCK	IoStatus,
		IN ULONG	MethodSetsCount,
		IN const KSMETHOD_SET *	MethodSet
	)

Definition at line 250 of file methods.c.

{
    KSMETHOD MethodRequest;
    KPROCESSOR_MODE Mode;
    NTSTATUS Status = STATUS_SUCCESS;
    ULONG Index;
    PFNKSFASTHANDLER FastMethodHandler;

    if (MethodLength < sizeof(KSPROPERTY))
    {
        /* invalid request */
        return FALSE;
    }

    /* get previous mode */
    Mode = ExGetPreviousMode();

    if (Mode == KernelMode)
    {
        /* just copy it */
        RtlMoveMemory(&MethodRequest, Method, sizeof(KSMETHOD));
    }
    else
    {
        /* need to probe the buffer */
        _SEH2_TRY
        {
            ProbeForRead(Method, sizeof(KSPROPERTY), sizeof(UCHAR));
            RtlMoveMemory(&MethodRequest, Method, sizeof(KSMETHOD));
        }
        _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
        {
            /* Exception, get the error code */
            Status = _SEH2_GetExceptionCode();
        }_SEH2_END;

        if (!NT_SUCCESS(Status))
            return FALSE;
    }

    /* are there any property sets provided */
    if (MethodSetsCount)
    {
        /* iterate through all property sets count */
        Index = 0;
        do
        {
            /* does the property id match */
            if (IsEqualGUIDAligned(MethodSet[Index].Set, &MethodRequest.Set))
            {
                /* try to find a fast property handler */
                Status = FindFastMethodHandler(MethodSet[Index].FastIoCount, MethodSet[Index].FastIoTable, &MethodRequest, &FastMethodHandler);

                if (NT_SUCCESS(Status))
                {
                    /* call fast property handler */
                    ASSERT(MethodLength == sizeof(KSMETHOD)); /* FIXME check if property length is bigger -> copy params */
                    ASSERT(Mode == KernelMode); /* FIXME need to probe usermode output buffer */
                    return FastMethodHandler(FileObject, &MethodRequest, sizeof(KSMETHOD), Data, DataLength, IoStatus);
                }
            }
            /* move to next item */
            Index++;
        }while(Index < MethodSetsCount);
    }
    return FALSE;
}

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