Re: building both monolithic command line program and shared library from single source package, ddcutil

[Sanford Rockowitz <rockowitz@minsoft.com>]

As I read the MonitorDarkly code, it manipulates the monitor by writing 
to DDC slave address x37, using operation code xC2.  xC2 is  apparently 
is the GProbe operation code.   (GProbe is the proprietary Genesis 
protocol.)  Operation code xC2 is not defined in the DDC spec, so it 
would never be used by ddcutil or any other spec compliant DDC/CI 
program.  It's the use of operation code xC2, not normal reference to 
manufacturer specific features with spec-defined operation codes, that's 
the "trap door".

On 1/27/20 7:50 PM, Paul Wise wrote:
> On Mon, Jan 27, 2020 at 4:50 PM Sanford Rockowitz wrote:
>
> > True. ddcutil internals were reworked some time ago for what I call User
> > Supplied Feature Definitions.
> Another aspect of manufacturer-specific features is that they can be
> used to do things that never should be allowed, like run arbitrary
> code inside the monitor. I wonder if the Linux kernel should be
> blocking access to at least the dangerous ones like Genesis' GProbe:
>
> https://github.com/redballoonshenanigans/monitordarkly