Re: [Qemu-devel] [PATCH] let management expire vnc password

[Dan Kenigsberg]

On Wed, Sep 30, 2009 at 09:43:13AM -0500, Anthony Liguori wrote:
> Dan Kenigsberg wrote:
>> On Wed, Sep 30, 2009 at 08:49:28AM -0500, Anthony Liguori wrote:
>>   
>>> Dan Kenigsberg wrote:
>>>     
>>>> After a client connects to vnc server, management may wish to expire the
>>>> vnc password, so that an attacker has less time to break into the vm.
>>>>         
>>> I don't understand what the use-case for this is.
>>>
>>> You want to basically lock out any new clients?  Can't you just set 
>>> the  password to something random?
>>>     
>>
>> Yes, and actually that's what we currently do. But having a random
>> password still opens a crack for guessing it.
>>   
>
> Is the requirement, prevent future clients from connecting to the vnc  
> server?  Essentially, disabling the vnc server?
>
> Could we do something more direct like add a 'vnc off' monitor command?   
> The nice thing about this approach is that we could add a flag to  
> disconnect all connected clients since someone else wanted that feature  
> in the past.
>

We would like to prevent future connection, but not to disconnect
existing ones.

> Can you explain the rationale for doing this though in a management  
> tool?  I'd like to better understand what sort of policy you're trying  
> to enforce.

The rationale is central management of access to virtual machines.

Normally, no vnc access to VMs is allowed. A user with enough
credentials may request the management tool for a short-lived
"ticket" to connect to a VM. If the user uses it, great. But after the
ticket expires, no further connections are allowed.

Regards,

Dan.