E
Eccentric OpenBSD User Dave
Is there any way on an x86 system that a working ps2 keyboard/mouse can be
disabled by writing data to the device?
Thanks.
disabled by writing data to the device?
Thanks.
Is there any way on an x86 system that a working ps2 keyboard/mouse can be
disabled by writing data to the device?
Thanks.
In alt.comp.hardware.amd.x86-64 Ed said:If using Windows (95-XP) you can use BlockInput.
http://msdn2.microsoft.com/en-us/library/ms646290.aspx
In alt.comp.hardware.amd.x86-64 Eccentric OpenBSD User Dave said:Thanks. Actually, I am running X windows and I was looking for info
about a possible exploit that I may be experiencing.
Why would you want to do this?Eccentric said:The question I am really trying to get an answer to is whether it is
possible for the cpu to send commands to the x86 keyboard/mouse that
will cause those devices to shut down permanently, effectively making
them useless.
In alt.comp.hardware.amd.x86-64 Marcus Red said:Why would you want to do this?
Eccentric OpenBSD User Dave said:The question I am really trying to get an answer to is whether it is
possible for the cpu to send commands to the x86 keyboard/mouse that
will cause those devices to shut down permanently, effectively making
them useless.
In comp.lang.asm.x86 Rod Pemberton said:Permanently?...
Does your BIOS may allow you to disable them, e.g., for USB or embedded? If
so, maybe CMOS is being corrupted. But, I'd think that would be temporary
and would block other keyboards from working...
You can temporarily disable access by reprogramming PIC's or sending
commands to the keyboard controller, if your OS gives you the privilege.
For the later to become "permanent," it could be written into the
bootloader, some part of the early OS stages, BIOS, video BIOS, etc. The
sequences are small and short. Of course, this wouldn't allow replacement
keyboards and mice to work...
If it's an exploit, as you mentioned elsewhere, you need to systematically
replace all possible "bad" code with good. First, wipe the CMOS, or you
could try toggling all the BIOS settings, saving, toggling back, resaving,
to "wipe" CMOS, then reinstall your bootloader, reinstalling FreeBSD,
reinstalling XWindows, and as a last resort reflashing your BIOS (taking
care with this one...), etc.
Ah good, I found the requirement a bit suspicious; I can't think of (notYANSWBVCG said:I don't want to do this, but I suspect that some X-related exploit is doing
it to me as a simple DOS attack. If this is *not* happening to me, then I
am buying really crappy mice and keyboards and need to switch to better
brands.
In alt.comp.hardware.amd.x86-64 Esra Sdrawkcab said:Ah good, I found the requirement a bit suspicious; I can't think of (not
to say there aren't any) any exploit to kill keyboard input (mouse
disabling being covered earlier).
OTOH, way back when (early 80's) there used to be games that required
the original boot floppy to run off, and some code on there disabled
Ctrl-Alt-Delete; so it may be possible.
Today I discovered that a kvm switch I have just started using is defective.
The mouse port to the kvm switch no longer works although a mouse taken
from that port and plugged directly into the computer does work. The kvm
switch joins the list of new equipment going mysteriously bad within weeks
of being placed into service with the AMD64 computer which itself has run
flawlessly in 64-bit mode for over a year now.
YANSWBVCG said:Today I discovered that a kvm switch I have just started using is defective.
The mouse port to the kvm switch no longer works although a mouse taken
from that port and plugged directly into the computer does work. The kvm
switch joins the list of new equipment going mysteriously bad within weeks
of being placed into service with the AMD64 computer which itself has run
flawlessly in 64-bit mode for over a year now.
<snip>Okay, this thread has become a "mystery novel" and I'm getting bored with
it. Each response seems to adds more information that wasn't mentioned
earlier... Since it seems we are no closer to finding the issue, I'll
"shotgun" some ideas for you:
Is there any way on an x86 system that a working ps2 keyboard/mouse can be
disabled by writing data to the device?
Thanks.
In alt.comp.hardware.amd.x86-64 Rod Pemberton said:Dave or YANSWBVCG,
Okay, this thread has become a "mystery novel" and I'm getting bored with
it. Each response seems to adds more information that wasn't mentioned
earlier... Since it seems we are no closer to finding the issue, I'll
"shotgun" some ideas for you:
1) The "hard errors" on the keyboards and mice suggest electrical problems
to me (blown circuitry, flaky cable, pepsi, heavy handedness).
2) The loss of usb etc., implies electrical problems to me (power dropout),
but could be software.
3) The "blown" KVM port implies electrical problems to me.
4) The locking of the cdrom drive is normal for Live-CD's if the OS has
mounted the CD for access or install or swap file, etc.
5) The locking of the cdrom drive if not mounted, e.g., hardisk or floppy
boot, suggests memory corruption to me.
6) The inability to access BIOS via delete key at boot could be a failure to
detect the CPU (overheated, overclocked), CMOS corruption (wrong cpu or bus
speed setting), or A20 issue (can't execute part of BIOS or video BIOS).
Does the BIOS detect the CPU? If CPU, this implies an electrical or heat
problem to me. If CMOS, this implies a software bug, like A20 being
disabled.
Completely unrelated questions, just in case there are multiple unrelated
issues...:
Is this a normal home computer, with a tower case?
Yes.
Or, is it this
"corporate?" If corporate, could it be sabotage, say from a vendor trying
to sell you stuff? What about a vendor stealing or a coworker (different
department) swapping bad stuff for the good "hardly used" stuff your
department has (I've seen this happen...a few times.)? Do the serial
numbers match what you bought? If a home PC, why the KVM switch?
Could the
KVM switch be blowing stuff as you replace it? Is this system being
overclocked (overheating, underpowered, "aged" circuitry from overclocking
or poor ventilation)? Was it moved just recently to near a window (memory
corruption from cosmic rays, solar rays, high energy particles, or
background radiation)? What are the PS ratings? What are the 12V current
rating(s) (underpowered)? Since it's an AMD, what are the 3.3V current
rating (since AMD's need more current on the 3.3V line)? Was the PC
recently "upset" by relocating, opening, dusting, vacuuming, etc. (loose
cables, memory or cpu not set in socket or slot, ventilation esp. rack unit,
static zapped)? Are you using RAID (hard disk failures)? Are you using
Western Digital hard disks?
No.
This link indicates that harddisk, raid, or memory errors occur far more
often than detected:
http://storagemojo.com/2007/09/19/cerns-data-corruption-research/
Rod Pemberton