[Qemu-devel] Re: [Spice-devel] spicevmv chardev, guest agents and paravirtual mouse

[Gerd Hoffmann <kraxel@redhat.com>]

   Hi,

>> (4) termial forwarding.  Just an idea right now.  Nowdays that the spice
>>       client side moves to gtk it would be easy to embed a termial widget,
>>       therby allowing easy access to the serial console using something
>>       like this:
>>
>>          -chardev spicevmc,id=console,type=terminal
>>          -device isa-serial,index=0,chardev=console
>
> I guess this could be used to get more info about the state of a VM from
> the host system (like "system is ready", "system is rebooting", etc),
> although it needs some adjustments in the guest to use the serial
> console and string parsing on the host.

That is really just for a terminal / serial console.  Running an guest 
agent protocol over a serial line instead of virtio-serial would be 
possible too, but that end would probably better handled by libvirt or 
some other management tool.

> Would it therefore make sense to
> have a another type to get such status messages from the guest and have
> a list of states defined somewhere? If yes, is this something which
> should be implemented in the spice-part or is this general qemu stuff?

It is general qemu stuff and how to design that best is the whole point 
of this agent discussion ;)

> Furthermore it would be nice if the client side could get a list of
> display resolutions supported in the guest and having the possibility to
> change the resolution when resizing the guest window. The vdagent
> protocol already has a message to pass this info but it only sends it
> when going into fullscreen mode.

That is just a client implementation thing.  The new spice-gtk client 
can send messages on window resize too.  Guest is supposed to pick the 
closest resolution it can handle.

> Yet another use case would be: authentication forwarding/injection to
> the guest OS. With smartcard-support you have something like that, but
> in our case we have the users authenticate against our management
> backend first before they get access to a VM and it would be kind of
> nice to be able to inject authentication data into the guest OS, either
> via the spice client or coming from the host OS.

Depends on the auth infrastructure whenever this is doable I guess.  If 
you are using x509 certificates the smartcard support should serve just 
fine.  I can also imagine that the guest can aquire kerberos tickets via 
spice-client or using some other agent for example (don't know kerberos 
good enougth to be sure though).

cheers,
   Gerd