Re: Need help. Proof of concept 100% security.

[Crispin Cowan <crispin () immunix com>]

Balwinder Singh wrote:

> I have developed an application, which I believe can provide 100%
> security against various attacks.I can hear people laughing. Hmm..
> The applications is called Execution Flow Control (EFC).
> Details of software can be found at http://203.197.88.14/efc
This sounds somewhat similar to our SubDomain 
<http://immunix.org/subdomain.html> product, which profiles applications 
in terms of what files they may access. It sounds very similar to the 
approach taken by Systrace 
<http://www.citi.umich.edu/u/provos/systrace/>,  Okena 
<http://newsroom.cisco.com/dlls/corp_012403.html> and Entercept 
<http://www.entercept.com/>, which like EFC, profile applications in 
terms of which system calls they may invoke.

At least Systrace also allows you to profile the arguments presented to 
syscalls, so you can fake SubDomain's file access control paradigm. This 
is important, because "touch /etc/pointless" is rather different from 
"touch /etc/hosts.allow". It is unclear from the EFC documents if EFC 
supports argument profiling.

The advantages of syscall access control:

   * more expressive: if you know that application Foo has no business
     calling e.g. mkdir, then you can catch exploits that try to
     leverage that kind of thing.

The advantages of SubDomain:

   * It is easier to generate a file access profile for an application
     than a syscall profile. Instead, SubDomain just has a long list of
     prohibited/dangerous syscalls for confined applications, letting
     the admin think about important stuff (which files to grant access
     to) and ignore less important stuff (who cares if *this* app calls
     getpid?).
   * Syscall mediation is prone to race conditions inside the kernel if
     it is implemented using syscall interposition.

Crispin

--
Crispin Cowan, Ph.D.           http://immunix.com/~crispin/
Chief Scientist, Immunix       http://immunix.com
           http://www.immunix.com/shop/