Re: Making C compiler generate obfuscated code

On Thursday 16 Dec 2010 at 15:23, Joshua Cranmer <Pidgeot18@gmail.com> wrote:
> I'm not sure what work has been done on deoptimization (perhaps anyone
> with the Hex-Rays decompiler could tell us?), but some of the
> optimization techniques seem relatively easy to reverse.
>
> From a purely theoretical standpoint, obfuscation that adds
> non-executing code is going to be less difficult to reverse engineer
> than obfuscation that does the same thing, just... less obviously.


A major theoretical result in this area is the paper "On the
(Im)possibility of Obfuscating Programs" by Boaz Barak et al,
published in: CRYPTO '01 Proceedings of the 21st Annual International
Cryptology Conference on Advances in Cryptology. Boaz Barak gives a
non-technical description of the results and their meaning here:


http://www.math.ias.edu/~boaz/Papers/obf_informal.html


The FermaT program transformation system can interactively transform
code into semantically equivalent forms: including restructuring,
simplification, dataflow analysis , SSA construction, slicing and, in
simple cases, abstraction to a specification. The FermaT engine and
graphical front end runs on Windows and Linux and can be downloaded
from here:


http://www.gkc.org.uk/fermat.html


or:


http://www.cse.dmu.ac.uk/~mward/fermat.html


FermaT's primary commercial application is migrating assembler to
structured and maintainable C and COBOL, so the "deobfuscation"
transformations are geared towards removing the "clever tricks"
introduced by assembler programmers to save a byte here and a cycle
there: or just because they were


--
Martin


STRL Reader in Software Engineering and Royal Society Industry Fellow
martin@gkc.org.uk http://www.cse.dmu.ac.uk/~mward/ Erdos number: 4
G.K.Chesterton web site: http://www.cse.dmu.ac.uk/~mward/gkc/
Mirrors: http://www.gkc.org.uk and http://www.gkc.org.uk/gkc

Return to the comp.compilers page.
Search the comp.compilers archives again.