OS X / Objc Reversing
nummish <nummish0x90org> Monday, April 7 2008 12:45.20 CDT


I've been doing some reversing on my mbp lately, and noticed there really isn't a large community resource for anyone reversing objective c binaries, or reversing on the apple at all. I know there are people doing it with all the iTunes DRM stuff and the iPhone unlocking scene, but everyone either keeps to themselves, or starts to look at a binary, sees all the symbols and walks away because it's too easy.

For the most part people seem to simply use otool+otx, class-dumper or IDA on parallels.

To make up for this vacuum of knowledge, I've put together a mailing list at 0x90.org for anyone interested in this topic. It's low traffic, but hopefully it can be useful in the long run.

http://0x90.org/mailman/listinfo/xso

Comments
shirkdog Posted: Monday, April 7 2008 13:38.00 CDT
Maybe you will be able to get some of that info into the reference library.

itsme Posted: Tuesday, April 8 2008 01:12.33 CDT
i wrote an ida .idc script to create structs, and name functions from all the symbol tables.

http://nah6.com/~itsme/cvs-xdadevtools/ida/idcscripts/fixobjc.idc


itsme Posted: Tuesday, April 8 2008 01:15.18 CDT
one thing to do when using hex-rays to decompile, is to add a '...' parameter to the typedef of objc_msgSend

int objc_msgSend(_DWORD, _DWORD, ...)

nummish Posted: Tuesday, April 8 2008 13:03.19 CDT
I have an idapython script I've been working on to do the same thing. I noticed you have the beginnings of of the argument type definitions in there. nice.