[Qemu-devel] QEMU as a "virtual smart card"?

["Bud P. Bruegger" <bruegger@ancitel.it>]

Hello everyone,

we are thinking of a possibly "exotic" use of QEMU and would like to
ask your advice on whether we are going in the right direction.

We are pondering of how to use a virtual machine to have some security
features normally associated with hard tokens such as smart cards.  

In particular, one of the key concepts of smart cards is that they can
store secret keys that never leave the device but can only be used by a
trusted and protected internal CPU for encryption/signing.  

At least looking naively at QEMU, it seems that its CPU and RAM are
well protected from the host operating system--in a way to say make it
practically impossible for some malware to extract the secret key used
in a virtual machine.  

Is this a valid conception of what QEMU does?  How good is the
isolation of a virtual machine from the host operating system.  

We are also interested in the isolation of input devices, in
particularly the keyboard as to prevent PIN sniffing.  My "naive"
impression is that key logging for a PS/2 keyboard is probably more
difficult than with a USB keyboard.  Is there any thruth to my
misconception?

Finally one last question questions:

* Is there any way of getting exclusive access to an USB pen drive
from a virtual machine, preventing the host operating system to say take
an image of the content?

many thanks in advance for any input and illuminations!

-bud