[Dailydave] Trojan Languages

Andrew munin at mimisbrunnr.net
Fri Nov 29 11:29:52 EST 2013


This is not a thing that LLVM is good at, really, at least not without
some care.

LLVM is "low level" in a way that means specifying integer bit widths.
This could be a problem when attempting to write code that works on 16,
32, and 64 bit platforms. You will go through many gyrations to ensure
that when you need to pass a 32-bit value to a system service, you will.
The language infrastructure won't help you here and you'll fight it.

The language and its infrastructure also isn't a "VM" in the way that
say the java VM is. For example, you will do your own memory management,
either in the code that you write, in the code that you generate, or in
a custom implementation of an LLVM interpreter.

Ultimately, your question of "why isn't this done more" can be answered
succinctly by "writing multi platform code is hard". C is multi
platform, I can write so much C code and build to target x86, arm, ppc,
mips, and weird TI DSPs by just changing stuff in CFLAGS. So why doesn't
every C program run on every microprocessor that we know how to code
generate for?

This is an advantage of python, because the python/java bytecode and
language has few (allowing wiggle room, if there was justice in the
world this should be 'none') places where there are hardware platform
specific concepts expressed. Pointers and references work the same,
multithreading and cache coherence works the same (or just doesn't, ha
ha python), GC works the same. The implementations of python are very
different though, and maintaining python interpreters that work on
ISA/hardware combinations is tricky.

Of course, using a dynamically typed, super-hard to analyze (all the
aliasing problems of C! except instead of a finite-sized integer key
into global memory we can use INFINITELY SIZED string keys into
"memory"! sign me up!) and quirky language
(http://pastebin.com/CB3SZJPK) to write code that is "much more correct"
is also I think playing on "way too hard" mode. Sometimes I think that
people that ask questions like "how do I make my programs fail less
often" should spend less time trying to emulate people that write dating
websites, and more time trying to emulate people who write (er, wrote,
gotta go drink in sadness now) code for the space shuttle...

Anyway, applied programming language technology is hard.

On 11/21/13 17:25, Mohammad Hosein wrote:
> are you using the civilian off the shelf Python ? if i was into typical
> enterprise pentest or offense biz two questions would be raised immediately
> - so the AV people need a tiny addition to their engines to particularly
> act out when something smells like python particularly when the calls
> are going down like ..the same route , well , since its always the
> standard python ?
> - isnt this a risk if our adversary finds out a node is active on her
> system and grab the thing and use the "forward-thinking technology"
> against us or their own favor whatever that is ?
> 
> obviously i am asking such "selling-session" standard questions like
> most .org/.gov typical customers to hear your technical counter argument
> ( presuming i am going to learn something , not get iced by a move like
> mad men's don draper in the scene where he talks about the candy in the
> brothel and what it meant to him -- a ceremony :> )
> 
> meanwhile i am going to put this out for folks at dd to hear back : LLVM is
> one the wonders of the world . although Duqu developers preferred to
> develop code based on their own framework ground up and flame used the
> typical lua embed , developing a middleware-style LLVM-based transformer
> to produce native code from some .py or .rb for almost any platform -
> x86 ..to ..say..  TI's rarely used DSPs - is easy work -- why using this
> technique isn't popular in "our circle" ?
> 
> -mh
> 
> 
> 
> On Thu, Nov 21, 2013 at 1:53 PM, Dave Aitel <dave at immunityinc.com
> <mailto:dave at immunityinc.com>> wrote:
> 
>     So as much as Chris tries to drive all of the complexity for
>     INNUENDO to the server, I find there's a sort of feature-gravity
>     that makes you want to put it onto the client. Even the simplest of
>     modules has a big enough state table and complexity that I'm tempted
>     to call it a "Behavior" and not a module at all. INNUENDO's client
>     is of course running Python, and I wanted to explore WHY for a second.
> 
>     Obviously one reason is that Immunity has a ton of Python
>     experience. But in trojans, Python is hardly most people's first
>     pick for a language. You're hauling 40Mb of code and data with you
>     when you want to run somewhere. This isn't ideal for a lot of
>     scenarios.
> 
>     But you're getting one, *very* important thing when you use Python:
> 
>     1. Your most complex code will be a lot less buggy.
> 
>     For advanced remote access trojans, you are operating in a
>     completely unknown environment and frankly, you may NEVER be able to
>     update it or reach it again. Any detection or failure could be
>     globally catastrophic. This means your code has to be forward
>     thinking in a way that is not typical. So it simply has to be much
>     more correct than code usually is. People tend to write complex
>     things more CORRECTLY in Python than in Ruby or Lua or
>     (Naudhubillah!) C. That reason alone is why the future of remote
>     access trojans is embedded Python engines. If you're trying to build
>     trojans that have emergent behavior, then you need a language that
>     makes that behavior as clear and easy to understand as possible.
> 
>     I mean, deep down, I refuse to give any ground whatsoever to the new
>     industry of incident response people who just realized how useful
>     instrumentation and anomaly detection is. It's time to tool up for
>     the challenges ahead! :>
> 
>     -dave
>     (P.S. You can mess with INNUENDO atINFILTRATE 2014 in Miami
>     <http://www.infiltratecon.com/>!)
> 
> 
>     _______________________________________________
>     Dailydave mailing list
>     Dailydave at lists.immunityinc.com <mailto:Dailydave at lists.immunityinc.com>
>     https://lists.immunityinc.com/mailman/listinfo/dailydave
> 
> 
> 
> 
> _______________________________________________
> Dailydave mailing list
> Dailydave at lists.immunityinc.com
> https://lists.immunityinc.com/mailman/listinfo/dailydave
> 


More information about the Dailydave mailing list