Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.debian.security > #4437

Re: Mandatory Access Control

Show all headers | View raw

No actually it is not Qubes what I am using.
I am using full blown qemu virtualization including a virtual wrapper 
device for the graphics. It is for sure that even here the weakest point 
is the emulation of the graphics card. I have even heard about HTML5 
code directly bugging your hardware via graphics acceleration (though 
this is rather theoretical because it would likely need to be customized 
to a certain graphics card). Nonetheless the weakness of Qubes is even 
more the GUI dom where all other doms connect to and which has direct 
access to the graphics hardware. Unfortunately I could not find any 
details on how it is implemented in deed.
Additionally I found it somewhat irritating that the basic description 
of the Qubes project talks so much about using Windows as a host. I 
would never trust software which is entirely closed source. Please do 
also note the following statement found in the intro when considering to 
use Qubes:
"Sure, a single kernel exploit destroys this all"

If you remember what I have told you about MAC systems then it was that 
a single public accessible system call which is implemented faulty would 
still compromise your system. Now consider that all current operating 
systems including Windows, Linux and FreeBSD are huge monolitic 
constructs making use of just two privilege levels/ security rings: user 
and kernel mode. At the introduction of the i386 (which is now still 
long ago) Intel suggested that at least three privilege levels would be 
necessary to build a secure system: the innermost for memory and process 
management, a middle ring for device and hardware drivers and the 
outermost one for user space programs. According to my knowledge and to 
what is public none of the operating system developers have followed 
these precautions until today (Xen is a different case as it uses three 
rings but not in the way as described above; actually it would need to 
make use of all four rings provided by the protected mode interface to 
be secure in theory - Nonetheless just believe me that things are not as 
theoretical in practice as this description may make you believe.).

Regards,
Elmar

On 29.11.2015 22:05, Patrick Schleizer wrote:
> Elmar Stellnberger:
>> If you wanna ask me for my security solution it is qemu based and puts
>> the most vulnerable system components like browsers and email programs
>> into a virtual machine namely qemu which is maintained by the Open
>> Source commnunity.
>
> Sounds like Qubes.
>
> Cheers,
> Patrick
>

Back to linux.debian.security | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Re: [SECURITY] [DSA 3405-1] smokeping security update Fredrik Kers <fredrik.kers@netrounds.com> - 2015-11-26 09:40 +0100
  Re: [SECURITY] [DSA 3405-1] smokeping security update Paul Wise <pabs@debian.org> - 2015-11-26 11:30 +0100
    Re: [SECURITY] [DSA 3405-1] smokeping security update Fredrik Kers <fredrik.kers@netrounds.com> - 2015-11-26 12:30 +0100
      Mandatory Access Control c4p0 <capo@riseup.net> - 2015-11-29 18:40 +0100
        Re: Mandatory Access Control Jason Fergus <leech@thefnords.org> - 2015-11-29 21:00 +0100
        Re: Mandatory Access Control Elmar Stellnberger <estellnb@gmail.com> - 2015-11-29 21:30 +0100
          Re: Mandatory Access Control Elmar Stellnberger <estellnb@gmail.com> - 2015-11-30 17:30 +0100
            Re: Mandatory Access Control Patrick Schleizer <adrelanos@riseup.net> - 2015-11-30 17:50 +0100
              Re: Mandatory Access Control Elmar Stellnberger <estellnb@gmail.com> - 2015-11-30 18:50 +0100
          Re: Mandatory Access Control Elmar Stellnberger <estellnb@gmail.com> - 2015-11-30 18:30 +0100
            Re: Mandatory Access Control Johannes Graumann <johannes.graumann@graumannschaft.org> - 2015-11-30 19:00 +0100

csiph-web