how to decompile an android NDK Library

[trizioPucci]

I have developed an Android Application with some data crunching inside a C library (NDK).

In order to protect the library code:

- I have obfuscated the code with ProGuard and exported it in signed release version.
- I have replaced the functions and variables names inside the C Library with random sequence of letters to let it unreadable.
- I verified the library with "readelf -a" command.
- I verify the apk with ApkTool

How can I decoded/verified that the library in the apk is correctly obfuscated?

Is there any way to explore and reverse the library (.so)?

Thank you!

[Jeffrey Walton]

On Fri, Nov 15, 2013 at 11:27 AM, trizioPucci <pucci.f...@gmail.com> wrote:
> I have developed an Android Application with some data crunching inside a C
> library (NDK).
>
> In order to protect the library code:
>
> - I have obfuscated the code with ProGuard and exported it in signed release
> version.
> - I have replaced the functions and variables names inside the C Library
> with random sequence of letters to let it unreadable.
> - I verified the library with "readelf -a" command.
> - I verify the apk with ApkTool

The preferred method is to remove sensitive data and code from the
distributed binary, and keep it on a server under your control.

> How can I decoded/verified that the library in the apk is correctly
> obfuscated?

APKTool and Jade will usually do the job.

> Is there any way to explore and reverse the library (.so)?

IDA Pro and friends. There's lots of free disassemblers and decompilers, too.

Jeff

[limelect]

Try my decompiler

http://www.limelect.com/android/

http://www.limelect.com/android/DiCompiler_Shell.html

בתאריך יום שישי, 15 בנובמבר 2013 18:27:24 UTC+2, מאת trizioPucci:

[Andrew Esh]

objdump -x ... and other args to objdump. There is a disassembler in objdump as well.

[trizioPucci]

Thank you for your suggestion. 
I have installed (WinArm) and with its objdump now I am able to see the assembly code inside my library.
Is there any free way to see the Decompilated version (like a C Code) of this library?

[Giuseppe]

Hi trizio,

have you found a solution to better obfuscation of C code ?