Questions tagged [decompilation]

Process of translating assembly code extracted from a binary file in a structured programming language, such as C.

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objective-c: getting source code from binary [duplicate]

I posted a question a few time ago but answers were not clear to me and the topic was closed because apparently the request was not clear: SO I clarify it: One upon a time a wrote a obj-c app but now ...
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At which address on the stack or in memory is eax stored after the malloc call? [closed]

Here is my objdump -d snippet with the malloc call and surrounding code. This binary is stripped. dbgLab.bin: file format elf32-i386 080483d0 <malloc@plt>: 80483d0: ff 25 04 a0 04 08 ...
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Can someone tell me what this memcpy or maybe it's a memset? looks like a memset, rep movsd and rep movsb This is a packet sending function

Trying to understand a function thats responsible for sending out a packet. I don't understand could it be a integer array or something? or some inline function that's not properly getting rendered in ...
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998 views

C What kind of sorting algorithm is this?

I decompiled a application and found what seems like some kind of sorting algorithm, I was told it's not even a sorting algorithm, but a binary search on stackoverflow I just don't know which one it ...
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Decompiling iPhone App

I've been searching this site and more, but I haven't had much luck. I want to decompile an app to see how part of it works, and I've tried multiple programs. I've tried Hopper, IDA, and some other ...
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Understanding x86 C main function preamble created by Visual C++

I was debugging a simple x86-64 program in Visual Studio 2010 and I noticed that the main function preamble is different from the GNU GCC compiled version of the same C program. To illustrate what I ...
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Decompilation techniques for DOS .COM files

I've found a binary copy of a DOS freeware game I was fond of back in the day (Firefighter, downloadable as FIRE.COM) but the source code is not available. I'd like to re-implement it in C or Python ...
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Converting assembly code to c

I have the following assembly code over Linux distro: # using the .data section for write permission # instead of .text section .section .data .globl _start _start: # displaying some characters ...
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How to decompile an Objective-C static library (for iOS)?

I'm trying to use IDA Pro v6.5 (freeware) (demo) to decompile an objective-c library compiled for ARM7-7S. I tried Hopper v2.8.8 (freeware) with no success. I had no problem until I tried to display ...
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1answer
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How to extract information from dll compiled in gcc with debug symbols?

I recently read that GCC annotates the source-code into the debug symbols it produces, although I haven't found any examples on how to retrieve this. If this is true, how can I view the data in the ...
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Get jar back from wrapped(into exe) jar

Is there any way to get a jar file from a jar wrapped using a exe wrapper. I have an exe file and I know that it was wrapper using exe wrapper (launch4j to be precise). How do I unwrap this jar to get ...
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Is it “theoretically” possible/impossible to reverse any binary?

I know that reverse engineering from binary to source code (e.g. C++) is generally considered hard or impossible but has any computer scientist actually proven "mathematically" that it's impossible or ...
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1answer
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How to convert this one-liner asm to C

I want to convert this to C: SHR CL,1 rECX is the name of the (32bit unsigned int)register variable. It should be simple, but I can't figure out the proper pointer magic :/
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Reverse engineer Android native code

I am looking for an reverse engineering tool or a way to decompile the existing android native code to an human understandable format rather than Assembly language. Can anyone please suggest me as i ...
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The debugger could not attach to the selected process

I want to debug an application which when opened, it will open a fork from it. e.g. program.exe will run 2 program.exe in the task manager the software is EMS SQL Management Studio for PostgreSQL ...
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Help with baml to xaml conversion? [closed]

i have used iLSpy to decompile a .NET EXE file after the process is completed. i copied the content of xaml files from iLSpy one by one, saved the as unicode files and replaced the baml files in ...
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Delphi Pascal Try..Except..Finally block

I'm having trouble reverse-engineering a specific Delphi Pascal .exe (old vsn., pre-1995 so probably v.3). From the system calls I understand this is probably a try..except..finally block, but I am at ...
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Why does Hex-rays thinks that 32bit PE is 16bit?

I'm using IDA 6.1 32-bit version. I'm pretty new to IDA and Hex-rays decompiling. My goal is to generate some C source from a 32-bit PE executable. I know this file is 32-bit PE executable. I've ...
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1answer
755 views

Decompile “Internal Call”

I have a .NET method which is marked as an "Internal Call", meaning that it is implemented within the CLR itself. Is there any way to locate the code for and/or decompile such a method?
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How can I decompile my (dot)NET .EXE file into its source code [duplicate]

I was working on a C#.NET application on windows platform, I was just testing the code and I don't know somehow I messed it up and after making too much efforts on undoing, I am still not able to ...
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3answers
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How to decompile Linux .so library files from a MS-Windows OS?

I would like to decompile the Linux .so files. Any tool to decompile .so files in MS-Windows based operating system ? Any tools/methods to decompile .so files ?
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What is difference between Digital Forensic and Reverse Engineering

I am not able to understand exact difference in Digital Forensic and Reverse Engineering. Will Digital Forensic has anything to do with decompilation, assembly code reading or debugging?
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How to zip or compress resources of your .NET application

I am a Windows application developer, I'd build a few .NET applications and I can see It is very easy to crack out resources of my Application even some simple applications like Resource Editor are ...
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3answers
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How to obtain x86-64 pseudocode in IDA Pro?

Does anyone know about obtaining pseudocode for x86-64 in IDA Pro? I already tried the Hex-Rays plugin to obtain pseudocode, but when I try it, the following error pops up: "only 32bit code is ...
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3answers
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Why are there (sometimes major) differences between java source code and its decompiled result?

I compiled some [relatively complex] Java code into a .class file, then used jad to decompile it back into java. Of course, the code was obfuscated, which was to be expected. However, given that I had ...
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How do you optimise AST's or convert them to a real language

I have been interested in automatic vulnerability assessment and decompilation of code for a while now. And as a result I have been building parsers in Python that reads a bin, disassembles it ...
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Decompiling return-oriented programs

How are return-oriented programs decompiled/reverse engineered ? Any pointers to any papers or reports would be appreciated.
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how to convert this ASM to C

I have this function that I know its responsible for making some nice math between a 2D vector to return the highest 3D Y value at the provided 2D coordinate. I also know it takes two parameters, int ...
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1answer
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Can a debug-apk be reverse engineered to make it a release-apk?

I am making a system in which the users can create Android applications. I want them to give an option to download a debug apk so that they can try it out first. After that, they have to pay for it to ...
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How to load a dumped process and several accompanied memory pages in IDA?

I have dumped process and several dumped pages of memory that were allocated in it. How can I load everything in IDA into one DB and reference pages in the loaded process?
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Is there any tool for decompiling raw binary files to C code for the Motorola 68000 processor series?

I have the ROM dump (.bin files) targeted for the MC68008 processor. Need to convert them into a high level source code. I have already found tools for disassmbling them into assembly code. The next ...
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1answer
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How to compile Hex-Rays decompiler generated code?

I need help to compile Pseudo-C code generated with IDA Pro and the Hex-Rays decompiler plugin. It shows an error on this line: int (__thiscall *off_401F14)(void *, char); // weak Error: error ...
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Is there a collaborative reversing forum for people that deal with firmware?

The question pretty much says it. Beyond knowing people that are interested in the same things, is there a collaborative reversing dumping ground for documenting specifically disassembly of closed ...
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Decompiling .pyc files

Does anybody have a suggestion for (non commercial) software to decompile "byte-code" Python (.pyc) files? Everything I've found seems to break...
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3answers
27k views

Reverse engineering a Visual Basic p-code binary

p-code is the intermediate code that was used in Visual Basic (before .NET). I would like to know where I can find resources/tools related to analysis of these virtual machine codes.
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Are reverse engineering and decompilation the same?

Is reverse engineering an application the same as decompiling it? What is the core difference between reverse engineering an application and decompiling an application.
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Possibilities for reverse engineering an ipa file to its source

I browsed a lot, but can't find any resources for reverse engineering an ipa file (iPhone application). Is there any method to reverse engineer an ipa file to its source? I've tried to rename it to ...
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5answers
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Open source GUI tool for decomposing a PDF

I've been looking for an open-source GUI tool to extract PDF's in an automated way on Windows systems. I've used Didier Steven's tools with great interest for a while, but cannot make sense of how to ...
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3answers
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Reverse engineer an old DOS QBasic executable

I recently decided to try my hand at reverse engineer an old DOS text based game that was coded in QBasic. I found some info online about old DOS games disassembly but mostly for Wacom compiled C/C++ ...
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1answer
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What is the state of art in LLVM IR decompilation?

LLVM IR is a fairly high-level, typed bitcode which can be directly executed by LLVM and compiled to JIT on the fly. It would not surprise me if a new executable format or programming language was ...
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What is a good Java decompiler and deobfuscator?

I am using JD-GUI to decompile Java JAR files, but the problem is that it leaves many errors, such as duplicate variables which I have to fix myself and check to see if the program still works (if I ...
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1answer
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How to investigate function calls across a batch of targets?

Say I have a collection of N executables, where N is large enough to make repetitive manual analysis tedious. I want to process all of these files and extract information about certain function calls, ...
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Why are machine code decompilers less capable than for example those for the CLR and JVM?

Java and .NET decompilers can (usually) produce an almost perfect source code, often very close to the original. Why can't the same be done for the native code? I tried a few but they either don't ...
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How to recover variables from an assembly code?

Assuming we have an assembly code, what are the known techniques that could be used to recover the variables used in the original high-level code ? Edit: By recovering variables, I do not mean ...
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How to differentiate from different hex files of different families of microcontrollers?

Is there any way to differentiate different microcontroller's hex files? I have a hex file and now I have forgotten of which micro-controller it belongs. Is there any available tool to tell this? or ...
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Is it possible to hide the details of which compiler was used?

The compiler adds system information to the output/object file that is created on compilation. Is there any compiler option that can prevent this information from being added? Can the compiler ...
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Can you decompile Actionscript 3 on a Mac?

Reverse engineering SWFs with ActionScript 3 on a Mac typically requires a Windows VM and a lot of copying and pasting. There are some good decompilers for Windows such as as3extractor but I haven't ...
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How do I figure out what is burned on an Arduino ROM?

I have an Arduino Uno Rev3. I would like to extract and find out what code is burned on the ROM of the micro-controller board. How do I extract the code from the board? How do I figure out the ...
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How can I turn .deb files back to .tar for reuse with other Linux distros? [closed]

We all know that Ubuntu is the most popular Linux distro today with plenty of application currently being developed for it. But then I use Fedora and some use other distros but still liked to have the ...
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Is there any way to decompile a .NET assembly or program?

Are there any tools available to take an already compiled .dll or .exe file that you know was compiled from C# or Visual Basic and obtain the original source code from it?