I want to see the code of an iOS app.
The app I downloaded is .deb.
First question: Is it possible to install .deb file on iOS or I downloaded a wrong file?
After unpacking the .deb file, I got some files, including .nib, .storyboard and some other files.
My main question is, How to decompile these .nib files?
I tried to decompile these files using NibToXibConverter, but I didn't succeed.
Answer to your first question:
I think you downloaded the wrong file. .deb files for iOS are common for jailbreak community and not for apps, I think all of the Cydia stuffs are packed into .deb's. If your app is especially made for the jailbreak scene then you may try to install it using Cydia's auto install feature on a jailbroken device.
Answer to your main question:
This is general info about decompiling and modifying iOS apps (not specific for nibs, but you may still find it useful).
iOS apps are distibuted in .ipa archives, which are ordinary zip archives. They contain, usually one executable in the form of Mach-O file, and resources like .plist, sounds, images - every resource you include in your xcode project. Decompiling the executable file is only possible on jailbroken iDevice, because it is encrypted especially for the current device and the magic key to decrypt the binary is burned inside the device CPU and as far as I know there is no software way to read that key. The encryption system here is called FairPlay.
Briefly described, one way to decrypt that binary is to have the app installed on a jailbroken device, and launch it from command line using a debugger (gdb) which you can download from Cydia. You have to set a breakpoint somewhere, and when your code execution pauses at the breakpoint, you are doing a memory dump of the device ram - and that is your decrypted bin.
So when you have the decrypted binary, you can run one tool called "class-dump", and get the information for declared classes and their methods if the app is written in Objective C. Once you know this information you can alter the implementation of given method from some class used in your app using "Cydia Subtstrate" a.k.a "Mobile Substrate". In fact that is the way all of the jailbroken iOS tweaks are made. Basically you are hooking a method call, and when that method get invoked, it uses your implementation. Furthermore your implementation can call the original implementation, and that is really useful if you want to make some small code addition.
I am not sure whether those things possible in Swift, but if you are dealing with a Hybrid app like the ones done with cordova, phonegap, etc., then you can see all of its javascript source because it is persisted as a resource inside the "ipa" file. In addition you can alter that javascript code directly if you have a jailbroken device and find where the app is installed on file system (usually /var/containers/Bundle/Application/uuid_for_your_app/). However, I think there is no way to get that patched version and redistribute it (correct me if I'm wrong).
Related
Suppose, I have some external executable file(call it a .swift file) that are not linked with the xcode project at compile time. That means, I did not have any of those files in my project tree when built the project.
For an example, lets say I have a file called exc.swift. This file was not included while I built the project.
Is there any way that I can execute that executable (the exc.swift) file at runtime?
In android there is a way by using DexClassLoader class. That class is responsible for executing code not installed as part of an application.
The documentation for that class is here.
Is there an iOS equivalent version of this? or in any way is this achievable?
If you are hoping to distribute the app that you are writing, then this is an absolute no-no. The app store review guidelines clearly state "Apps that install or launch other executable code will be rejected" so no app that exhibits this functionality will ever get onto the app store. You may be able to find or devise some kind of hack or workaround to get this kind of thing to work, but it will only ever be for your own amusement.
I am delivering an iOS app for a client and they are asking for the compiled/build files for the app and not the source code or an exported .ipa. I am wondering what compiled/build files are.
Is it just the .app that is created in /products whenever I build my app or something else that I need to do? I believe they are after these files so they can sign the app with their own production provisioning profile and to create a .ipa themselves.
What is an iOS app's compiled/build files and if it is just the .app how it differs from an exported .ipa?
Although vague, it's also possible they're looking for an Xcode Archive. This includes the compiled .app file as well as symbol information. You can build an archive to seed an application for testing or to validate and submit an application to iTunes Connect. If they want to submit or distribute the app without the source code, this is how you would do it.
"Building" is a fairly general term, and it can refer to anything that is needed to go from editable source material (source code, scripts, raw data files, etc.) to a shippable software product. Building can (and usually does) involve several steps, such as pre-processing, compiling, linking, converting data files, running automated tests, packaging, etc.
"Compiling" is more specific, and almost invariably refers to a process that takes source code as its input, and outputs something runnable, typically machine code for either a physical or virtual machine, or source code in a different language.
I bet they are wanting the .app. Unfortunately, since they are being relatively vague with their request, I think you should confirm this with them. I wouldn't feel uncomfortable asking, because their terminology is not some universally accepted way of refering to some method of building iOS applications. Or, if you can find out what they plan to do with the compiled binary, that might help understand what they need.
FYI, here's a brief description of the difference between a .app or .ipa.
How easy is it to open up an app submitted to Apple's store?
I'm going to submit a new app to the store soon, and want to protect the app file from being opened up to the source-code. So for instance, if I were to download my own app, how easy would it be to pull out all the .h and .m files and recreate it in Xcode?
Does Apple encrypt it somehow?
What steps can I take to mitigate the code being viewed?
EDIT: Allow me to rephrase the question a little better - can I take decompiled code and make it human-readable?
An IPA is just a zip. But you don't even need to access the IPA.
Just get iExplorer and access all available assets of your installed apps from your Mac.
The m files however build a compiled binary and can not be read (if you consider de-compiled code as not readable, as I do)
Adding on the answer, it is possible to decompile the binary, but the only thing that would be directly removable from the binary itself would be the headers (or to my knowledge of what I've seen). Then the application would be reverse engineered from there. That would probably be the only thing I'd be worried about when it comes to people stealing my code.
I was trying to get the header files from the ToneKit framework on iOS7.1, but I found that I cannot use class-dump because there are no executable files inside the framework. From what I have found after some research, it seems as if the actual executable file is inside the dyld_shared_cache on the device. After reading this article, it seems as if there are some tools to decrypt the cache, but since iOS 3, Apple has implemented ASLR which has made the decryption tools not work. How can I extract the Frameworks from inside the dyld_shared_cache on iOS7.1?
I am very new to jailbroken ios development so please bear with me.
If you're interested in how they got those headers then the answer is very simple - iOS SDK. SDK contains ARM binaries of public and private frameworks because they are required to compile iOS applications. Class-dump them and you will get headers you need. ToneKit.framework binary is also in there.
Usually you don't need dyld_shared_cache, almost everything you need is either in iOS SDK or on a device itself like SpringBoard, other system applications etc.
Of course there are rare cases when dyld_shared_cache is the only place you can find certain binaries as they are missing from both iOS SDK and device. In that case I use IDA. It has free demo version that can open dyld_shared_cache files - you can even open individual binaries inside it rather than dump everything. You just need to copy dyld_shared_cache on your PC.
I think Elias Limneos's classdump-dyld can help you. If not, check out RuntimeBrowser. Failing that, even, weak-classdump has proven to be a very useful runtime tool for me.
I have been given a Shared Object file (.so) and the functions inside of it, but I don't have a clue as to how to use it, or alter it for use in an iOS application. Could someone point me in the right direction?
I know the .so came from an Android application, but I was told I could get it to work in an iOS application as well.
Actually and technically, yes, you can, but not in a way you would ever think.
If it came from Android, it is probably compiled for ARM. So it should be binary-compatible with the ARM CPU in iOS devices. However, iOS doesn't use the usual format of shared objects (that is, the ELF format), but iOS' and OS X's own Mach-O format.
This means that you cannot directly link against this shared object file nor are you able pass it directly to dlopen() and dlsym(). You have to get into serious hacking (something that you probably don't know). This involves loading and relocating the file properly.
An example of this can be found in iOS jailbreak developer and hacker, Comex's GitHub repository Frash, a Flash player for jailbroken iOS devices. Comex essentially wrote an ELF loader module (dubbed "food") for iOS and used it to make Android's libflashplayer.so work on iOS. Pretty neat, huh?
Also note that this is not going to be possible for AppStore apps as it needs dynamic loading and various alterations in the OS.
while technically possible (see h2co3's answer) for anything practical the answer is no
so files arent in the correct binary format
even if they were, dynamic loading is not allowed by appstore