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

[Blue Swirl]

On Wed, Sep 2, 2009 at 2:47 AM, Jamie Lokier<address@hidden> wrote:
> Bud P. Bruegger wrote:
>> 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.
>
> No, the CPU and RAM state inside QEMU is easily read from the host.
> Just run a debugger and attach to the running QEMU process.  It's not
> completely simple, but it's far from secure.

For additional complexity, the CPU registers, memory, instruction set
and I/O could be encrypted but there is still a problem: where to
store the keys. The keys could be handled by another host process,
which could also try to attest that no debugger is attached (at least
on that level of virtualization). Performance would suck of course and
the attestation process could be fooled.