Function VirtualizeProcessor

Kernel-Bridge/API/Hypervisor.cpp:473–565

Virtualize the current logical processor:

    // Virtualize the current logical processor:
    static bool VirtualizeProcessor()
    {
        using namespace PhysicalMemory;

        static volatile bool IsVirtualized = false;
        IsVirtualized = false;

        CONTEXT Context = {};
        Context.ContextFlags = CONTEXT_ALL;
        RtlCaptureContext(&Context);

        if (IsVirtualized) return true;

        // Enable the SVM by setting up the EFER.SVME bit:
        EFER Efer = {};
        Efer.Value = __readmsr(static_cast<unsigned long>(AMD_MSR::MSR_EFER));
        Efer.Bitmap.SecureVirtualMachineEnable = TRUE;
        __writemsr(static_cast<unsigned long>(AMD_MSR::MSR_EFER), Efer.Value);

        PRIVATE_VM_DATA* Private = reinterpret_cast<PRIVATE_VM_DATA*>(AllocPhys(sizeof(*Private)));

        // Interceptions:
        Private->Guest.ControlArea.InterceptCpuid = TRUE;
        Private->Guest.ControlArea.InterceptVmrun = TRUE;
        Private->Guest.ControlArea.InterceptMsr = TRUE;
        Private->Guest.ControlArea.MsrpmBasePa = reinterpret_cast<UINT64>(GetPhysicalAddress(&Private->Msrpm));

        // Guest Address Space ID:
        Private->Guest.ControlArea.GuestAsid = 1;

        // Nested paging:
        BuildNestedPagingTables(&Private->Npt);
        Private->Guest.ControlArea.NpEnable = TRUE;
        Private->Guest.ControlArea.NestedPageTableCr3 = reinterpret_cast<UINT64>(GetPhysicalAddress(&Private->Npt.Pml4e));

        DESCRIPTOR_TABLE_REGISTER_LONG Gdtr = {}, Idtr = {};
        _sgdt(&Gdtr);
        __sidt(&Idtr);

        // Setting up the initial guest state to the current system state:
        Private->Guest.StateSaveArea.Gdtr.Base  = Gdtr.BaseAddress;
        Private->Guest.StateSaveArea.Gdtr.Limit = Gdtr.Limit;
        Private->Guest.StateSaveArea.Idtr.Base  = Idtr.BaseAddress;
        Private->Guest.StateSaveArea.Idtr.Limit = Idtr.Limit;

        Private->Guest.StateSaveArea.Cs.Limit = GetSegmentLimit(Context.SegCs);
        Private->Guest.StateSaveArea.Ds.Limit = GetSegmentLimit(Context.SegDs);
        Private->Guest.StateSaveArea.Es.Limit = GetSegmentLimit(Context.SegEs);
        Private->Guest.StateSaveArea.Ss.Limit = GetSegmentLimit(Context.SegSs);
        
        Private->Guest.StateSaveArea.Cs.Selector = Context.SegCs;
        Private->Guest.StateSaveArea.Ds.Selector = Context.SegDs;
        Private->Guest.StateSaveArea.Es.Selector = Context.SegEs;
        Private->Guest.StateSaveArea.Ss.Selector = Context.SegSs;

        FillVmcbSegmentAttributes(&Private->Guest.StateSaveArea.Cs.Attrib, reinterpret_cast<const SEGMENT_SELECTOR*>(&Context.SegCs), &Gdtr);
        FillVmcbSegmentAttributes(&Private->Guest.StateSaveArea.Ds.Attrib, reinterpret_cast<const SEGMENT_SELECTOR*>(&Context.SegDs), &Gdtr);
        FillVmcbSegmentAttributes(&Private->Guest.StateSaveArea.Es.Attrib, reinterpret_cast<const SEGMENT_SELECTOR*>(&Context.SegEs), &Gdtr);