How to obfuscate iOS binary. - ios

Hi, I'm just wondering how you could obfuscate functions in iOS binary?
If you tried to reverse iOS binaries using tools like ida you will see part of the binaries have obfuscated functions like all or partly named sub_xxxxxxxx but the other have human readable functions
Someone said, add those lines to the top of your header without any further explaining:
#define SecurityClass ah7p
#define checkCopyProtection xcyc
What the methods used to secure your App?
Sorry for the dumb question, but I'm new there and I ended up with no answer explained what I need.

There are a couple of ways to obfuscate an iOS binary.
Open Source compiler named llvm-obfuscate (https://github.com/obfuscator-llvm/obfuscator/wiki) It has some nice features to obfuscate during compilation. You are replacing your default compiler with that one.
There are for Windows of course VMWare oder Themdia that can post process but that is not the case.
Besides that I just know one more which is Liasoft antispy. It is a very advanced anti analysis toolkit that allows you to encrypt functions and much more during compilation using mixed Objective-C and C++ code. ( https://www.liasoft.de/en/products/antispy/ )
Not sure if one of these is the right one for you. Except these things you are pretty lost since Objective-C is a compiled language with lots of metadata.
Hope I could help you, this is my first post.

If you only care about obfuscating method names then the easiest way is to write relevant parts of your application in C or C++. For instance, you can rewrite your SecurityClass as a C++ class instead of Objective-C class. This will not make your code reverse-engineering-proof, but it will at least raise the bar a bit. (NOTE: I'm not saying this is the right thing to do from software engineering point of view, though).
If you need to obfuscate code, then you are in a search for a tool that can do this. There are several such tools, both commercial and free. One project for doing exactly this is obfuscator-llvm.

Related

How to correctly build a swift framework for iOS

My goal is to build a swift iOS framework which uses two other frameworks (included as separate projects) and which shouldn't reveal the source code after built.
Is there some text/guide/documentation which would explain and navigate me through the process of building such a framework properly and correctly?
I built framework with aggregate target adding and linking frameworks on which my custom framework is dependent using run script as indicated here. I was able to add built of my custom framework to my custom app, together with other two dependencies (again as a separate projects), and run it on the device. However, I am not convinced by the correctness of my custom framework built.
Moreover, I was not able to upload the archive to the Appstore due to the various errors of "Unsupported architectures...", "CFBundleIdentifier Collision...", "Invalid Bundle...", "Invalid Binary" and so on. After sorting these errors out according to the various stackoverflow answers and installing the app from the TestFlight, the app crashed after launch and wasn't working at all.
I was checking various blog posts, stackoverflow questions/answers and Apple Framework Programming Guide but nothing gave me comprehensive understanding on building custom framework under conditions described above.
Everything I did was just following step-by-step tutorials without explanation of the purpose of the steps. I am sure I am missing the basics. Could you please help me and give me some guides?
I can understand you frustration. I, a while ago too searched probably for many documents on how to write a framework correctly but like you I also didn't find anything really that satisfying. From my own experiences I can give a couple of advices.
NO External Libraries
In my opinion DO NOT use external libraries in your own framework. I don't really know what your frameworks purpose is but most of the stuff you want to do can be done without using external libraries. Depending on other libraries is not a good idea especially if its a framework you are working on. Anytime these libraries get updated or even worse if they don't you will have to wait for them to be updated or find another library.So rather than this happening later on I think its better if you do it from the start. So loose the external libraries.
Universal Framework Binary
Second one is pretty easy. Generating a universal framework. I suggest you don't use a script. Most of the scripts I found were either outdated or they didn't work at all. Later on I found out that actually it was pretty easy to generate one on your own. You can do this by building your project once for a real device and one for the simulator.Then you can generate a universal binary by using the command lipo -create "Your simulator executable path" "your iOS device executable path" -output "your framework name". What this does is that it combines your two executable files and generates a universal one. Then you can just go and copy your simulator documents from the modules file and paste them in you iphoneos modules file. I am going to share a link were you can go through the walkthrough yourself. https://medium.com/wireless-registry-engineering/create-a-universal-fat-swift-framework-b7409bbfa18f
Use Objective-C(If you can)
This one is bit of a tricky one unless you know objective-c. What I would recommend is that you implement your framework using Objective-C and writing a swift wrapper around it. I would not have said this if you were creating an iOS app but in case of a framework I still think you should go for objective-c. This is because Objective-c has been around for over 30 years and most of the very old apps are in objective-c. If you want your framework to easily be used by older apps coded in objective-c I recommend you go with it. I have read tons of posts on how people have problems trying to use frameworks written in swift in their objective-c apps. Swift will be the first and probably only choice in the near future but not just yet. On the plus side if you still haven't you will have learnt Objective-C which will give definitely give you a better understanding on how things work. It will be challenging but I promise you it will be worth your while .I have a good read on this which you can checkout yourself. https://academy.realm.io/posts/altconf-conrad-kramer-writing-iOS-sdk/
Naming Conventions
This is a pretty straight forward one. I suggest you stick to apples naming conventions. This is because you will be sharing your code this time and people will look for familiarity when trying to integrate your framework. This will make your code easier to understand. You can check out these two links for more info.https://github.com/raywenderlich/objective-c-style-guide (obj-c) https://github.com/raywenderlich/swift-style-guide (swift)
Access Control
This in my opinion is an important one. When working on you framework think before you implement a class or a function. Consider if you would like someone else to be able to use that part of your code. You may want to limit the user while they use your framework and correct access control is the way to do it. You can easily guide the users so the users do exactly what you want them to do with your framework.
Document Your Code
This is a must if you want your framework be a professional one. You should be documenting every function and variable the user will use. Documenting and explaining what your code does makes a lot of peoples lives easy. You don't one anyone trying to understand what your code does for half an hour while you could have easily written a small explanation for what the parameters do and one that function or variable should be used for.
Test Your Code
Last but not least do write tests for your code. This does take some time but it assures you that your code works the way it should.
Look at other good frameworks
You should definitely checkout other open source libraries and look at what they have done. Usually there is no point in reinventing the wheel unless you are doing something absolutely different but even then there are very familiar ways to do things. I can suggest you check out the mantle sdk(https://github.com/Mantle/Mantle). Another one is the very popular Alamofire sdk(https://github.com/Alamofire/Alamofire) and also the Realm sdk(https://github.com/realm/realm-cocoa). These are good examples of frameworks. Take a look at them. Look how they have done things. It will give you an insight on how your framework should look like.
I know all of these points may also be valid if you were writing an app but what makes these a must is the fact that you will be sharing your code with others. You may manage by not doing some of these while implementing an app but for a framework things do change a little bit. It is always a pleasure to work with easy to use frameworks which make coding a pleasure. These types of small things will make your framework preferable. Happy coding.

UML class diagrams for Xcode (Swift programming)

I have created an iOS mobile application. Is there a way to generate a UML class diagram for the Swift programming language?
I have tried Omni Graffle, but it keeps saying that the project doesn't contain Objective-C interfaces. And Omni Graffle only does this for Objective-C.
I remember looking at this question a while ago and was disappointed that there wasn't any tool like this so I created one myself with the help of a colleague. It's free, it's open source, it's looking for contributors...
https://github.com/yoshimkd/swift-auto-diagram
And here's a tutorial on how to use it (don't worry it's very simple):
https://martinmitrevski.com/2016/10/12/swift-class-diagrams-and-more/
Happy diagraming :)
The answer unfortunately is: you can't do it. At least not automatically. Swift as compiler itself has enough flaws left. Leave alone some tool will be able to swallow any Swift code. Your only alternative is the good old manual way.
I know that Enterprise Architect has a possibility to define a language syntax based on BNF. But Swift is (again unfortunately) not context free. (In fact it's so context sensitive that it often swallows its own rear.) So that won't work either.
P.S.: Now that Swift is open source someone might take the opportunity to tap the compiler's output for the class interfaces. I guess that should not be too difficult, but it's a lot of work still.
Inspired by swift-auto-diagram and similar open-source tools I started to work on such utility with the goal to write it in Swift (to make contribution easier by Swift developers) and to integrate it in Xcode and the Swift ecosystem.
Xcode extension: https://github.com/MarcoEidinger/SwiftPlantUML-Xcode-Extension
You are able to generate a class diagram from selected lines of code or from a whole file displayed in Xcode. The class diagram will then be opened in your browser. There you can modify the diagram with PlantUML notation
To generate a class diagram from multiple source files you can use the underlying CLI tool and Swift Package: https://github.com/MarcoEidinger/SwiftPlantUML
There is a size limitation to the visible diagram content (but you can delete content in the browser with PlantUML notation)

iOS SDKs: Renaming a lot of classes

I'm developing an iOS SDK that integrates other SDKs (Facebook SDK 3.5, for example).
To prevent collisions and allow my customers to import those SDKs as well, I want to rename all of the classes/enums in my code (for example, rename FBSession to RDFBSession, etc).
Is there an easy way to do this instead of going class-by-class and using Xcode's rename feature?
Apple provide a command-line tool called tops(1) that is designed for scripting large-scale code refactoring (renaming C functions, Objective-C methods, classes, and other tokens):
tops -verbose replace "FBSession" with "RDFBSession" Sources/*.[hm]
If you have a lot of replacements, you can put all of the replace... commands into a file that you pass with the -scriptfile option. The man page has more information on the more complex commands/options (and examples).
Xcode also offers textual Search and Replace. This will be faster than individual refactors, but it is ultimately less automated. You can make the step by step refactoring faster by first minimizing the project to the relevant dependencies/sources (if possible).
However, renaming the declarations in a library will not alter the symbol names of its associated binary. If it is distributed with a binary, then renaming will just result in linker errors or (in some cases) runtime errors.
The best idea if you need to use a 3rd party library which your clients might also use is to simply inform them they need to link the library with their app, then publish the version(s) the current release supports so they know they have some extra testing if they go too far ahead with some libraries.
I think that a better approach than simply renaming your classes would be to download Facebook's open source code, rename the classes there and compile a new static library with a set of renamed header files. Then you can be sure that no collisions occur and that you're using symbols that you named yourself.
I must warn you though - working like this may make updating the SDK a nightmare regardless of how you tackle this specific issue.

Using Syntax Highlighting

I'm trying to write an IDE for the iOS and I stumbled on a problem. I of course wanted to be able to do syntax highlighting, but I have no idea how I have to get this to work.
I have been googling over a month now, but I haven't found anything useful. Most libraries are C++. That I find no problem, I know enough of C++, but they all use the Boost libraries and I heavily doubt if it's easy to install them on a jailbroken iOS device, or even compile them for the iOS on the Mac.
So I come here for help. What should I do? Should I use a PHP syntax highlighter, which always colors the whole document? Should I write a syntax highlighter my self, that doesn't use the Boost library? Or does somebody here know another library, which can be used on the iOS?
Thank you in advance,
ief2
i have a simillar problem about syntax highlighting, but i prefer to solved it using UIWebview than using core text, because that is a different pixel in rendering text in core text and UITextview (in my problem i was using a core text view that cover by uitextview), and then i try to solved using uiwebview, even i'm still on developing but i can say that it is better using uiwebview than core text, maybe you can take a look at this link http://alexgorbatchev.com/SyntaxHighlighter/ it is an open source code, but it develop using javascript.
Most Boost libraries are header-only. There are only a few Boost libraries, like those for threading and asynchronous I/O, that use a compiled library. If you've found some solutions that would work fine aside from your worries about using Boost, then I would look at them again, as they'll likely work. Even if you must use a Boost library that is not header-only, you can always build it as a static library and link that into your application, so that in the end the only thing that needs to be installed is just your app bundle.
I know this is old, but in case anybody is looking for a complete syntax highlighter for iOS, there's two options:
Highlightr: A Swift library for syntax highlighting, supports hundreds of languages but uses JS as backend. It's fast enough for live editing, though. (Disclaimer: I am the creator of this library).
SyntaxKit: A native solution on early stages of development. Should support any TextMate syntax in the future.

CPAN/gem-like repository for Objective-C and Cocoa?

Is there any centralized repository of useful Objective-C / Cocoa libraries as there is for Perl, Ruby, Python, etc.?
In building my first iPhone app, I'm finding myself implementing some very basic functions that would be just a quick "gem install" away in Ruby.
There's a project for that! It's called CocoaPods!
Homepage: http://cocoapods.org/
Source: https://github.com/CocoaPods/CocoaPods
Unfortunately not :(
There are some very useful sites however. I find one of the best is cocoadev.com as it contains lots of useful information about many of the more obscure classes usually including snippets of code to do some really cool things :)
Maybe we (the cocoa community) should look into building something like this!
Oh and I just remembered this site cocoadevcentral.com which is also very good for starting out with cocoa.
Daniel mentioned http://cocoadev.com.
More specifically, check out http://www.cocoadev.com/index.pl?ObjectLibrary.
"This page is for tracking re-usable Cocoa classes that can be mixed, matched, and dropped fairly easily into existing Cocoa projects to add useful functionality."
I'd be interested in what kind of "basic functions" you're having to implement. There's actually quite a lot already there in the provided libraries, and I wonder if you're just not finding functionality that's already there...
There's a new index of reusable code for Mac OS and iOS: Cocoa Objects
I might be confused or missing something here... But doesn't apple provide all the Foundation / Cocoa / AppKit / CoreAudio / Qtkit / etc libraries that should provide all of the very basic functions you are looking for?
Other than what xcode comes with or is on the apple dev site, there are no centralized repo's for Cocoa.
Google Code also has some objective C things up. It depends on what you are looking for...
Also see GitHub, many useful Objective-C projects, especially re iPhone. See activerecord & cocoaoniguruma, for instance.
http://github.com/search?q=objective-c
http://github.com/search?q=objc
Google has Google toolbox for mac which got me started unit testing my iPhone application which was the main thing I found missing.

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