View Full Version : PatchDiff2 Analysis and Decompilation

June 11th, 2010, 12:13
Now that PatchDiff2 is open-source ("http://code.google.com/p/patchdiff2/"), I release my IDB and the initial decompilation that I did. You can find it here ("https://www.openrce.org/repositories/users/RolfRolles/PatchDiff2.zip").

I met the author, Nicolas Pouvesle, at RECon 2008, who told me of his upcoming plans to release this plugin. He mentioned that the license would be friendly towards reverse engineering, so I asked him if I could decompile the plugin and release the source code. We must have miscommunicated, because I could have sworn he gave me the green light.

When it was released, I spent about three days reverse engineering and decompiling it, resulting in the workproduct linked above. I had intended to spend an extra couple of days on the decompilation to make sure it was functionally equivalent, if not byte-perfect (which is always the ultimate goal).

After I finished the initial phase of the decompilation, I sent it over to Nicolas to solicit his feedback. He informed me that releasing the source code would violate PatchDiff2's EULA. Therefore, I abandoned the project. As it stands, I never even tried to compile the source code, so I'm afraid it's not worth much beyond the mere curiosity. Still, I'm releasing this hoping that somebody might find it interesting. The IDB itself is very thorough, e.g. all structures are recovered.