We are writing a corporate app which will run on a small number of in-house iPads. There will be a need to provide a number of (structurally identical) 'setups' on each iPad, and those setups will contain confidential data. My question is, what's the best way of getting those setups securely onto a device (into the app's private storage).
So far we've considered:
Download from web. This is problematical because we'd have to do quite a lot of work to make this secure.
QR codes. Render the setup as a QR code. We can generate and scan QR codes which represent the setups (they are quite small), but it looks like the available QR code APIs are either quite expensive or a little complex.
iTunes downloads. This is being looked at but I'm not sure what the security implications are.
Have we missed something simpler?
Edit: Just to clarify, a setup takes the form of a small file. It could be XML or JSON or even plain text: it just needs to encode about ten variable names and their values.
It's not clear what you mean by "iTunes downloads". If this isn't referring to iTunes File Sharing, then you should look into that. The user can add files onto the device for particular apps through iTunes.
It's also not clear what you mean by "secure" - this has very different meanings to different people. Sticking an SSL cert onto a server and providing HTTP auth is simple enough. What kind of security beyond that are you looking for?
If QR codes are acceptable, I suggest you look at zxing library. The code contains an iOS example project that you could base your implementation on.
There are some useful web resources to help with implementation: http://yannickloriot.com/2011/04/how-to-install-zxing-in-xcode-4/
Related
How easy can it be for people to see the code / inner working mechanics of a published iOS app?
E.g if there was a certain algorithm or function/class, how easily could people be able to read that?
If it’s possible, is there any way to camouflage or encrypt it so the code can’t be read?
Cheers
A certain algorithm or function/class is not going to be visible to anyone just from having access to a published app. The apps executable has been compiled and optimised so the original source does not even exist inside it. The executables are also encrypted and while can be decrypted if you jail brake a device even then you won't get much info.
While a lot of information about how an app works can be deduced by examining how it works individual algorithms is not something to worry about.
Plus what makes you think anyone is even going to bother trying for your app.
EDIT
As there was some confusion here is a link which talks about the binaries being encrypted when producing universal and thinned ipa files:
https://developer.apple.com/library/content/qa/qa1795/_index.html#//apple_ref/doc/uid/DTS40014195-CH1-APP_STORE_CONSIDERATIONS
At first, I will describe my use-case on why I need to add the framework at runtime on iOS.
Let's say I have an app on iOS device. The app requires some 3rd party frameworks to add some external features to it. Now, the features are many. So, the required number of frameworks will be many too. An user may not need lots of features. Just a small set of features. Plus, lots of framework will require a lot of space. The application will be huge in size.
For an example, an user needs only 1 feature. The application provides 100. So, all the other frameworks will definitely be unnecessary.
So, the solution would be to download the frameworks and the necessary files on demand from an online repository, link them on runtime and use them. This would mean the application size would be very small and not bulky with unnecessary stuff.
But does iOS provide that? I have to add an external framework and the necessary files that is not on the app use them on runtime.
Is this possible? Can anyone provide me with some resources on how I can do that?
I have seen some resources on SO and some other sites. The results are not so helpful.
"But does iOS provide that?" - no
"Is this possible?" - partially
"Can anyone provide me with some resources on how I can do that" - unfortunately no
More details: That is certainly not possible out of the box. And it will be firstly a pain in the ass to do achieve what you are trying and (far more important) secondly it will probably not be allowed by Apple. You are not allowed to load new "program code" into the app at runtime. For the simple reason that Apple cannot review what you are about to load. And it would a huge security risk for your users if your backend gets compromised.
What you can do is load resources like images, videos etc. on demand.
You might even be able to come up with some scripting behavior of your app. The server could theoretically deliver code to your app and then your app interprets that code. But that code would not be Swift but some other language that you have to define first. You see where this is going? That is possible while not really doable. And still it might get you rejected anyway.
In particular if you are talking about actual frameworks that include actual binary code is is not possible.
I have an sqlite table and some audio in my iOS application that I have put a lot of work and effort into, but looking through iFile or any other browser based application I can easily find these files and do whatever I want with them. If I can do this then someone else and more malicious than myself would be able to do the same.
How can I obfuscate my files while keeping them usable?
What you need to do depends on who you are protecting them from.
Using NSData "Data Protection" will protect the file only wheb the iDevice is locked—at best but is a step up.
Another method is to encrypt them with a key which you save in the keychain. on an iPhone 6s can encrypt 1Mb in 6ms, an iPhone 4s in 30 ms (using Common Crypto), so there is really no noticible speed degradation. A good candidate for this is a 3rd party library: RNCryptor, it handes many details needed to do this right. The attacker will have to be more than a cyrious user, this may meet your needs.
You need to define the attacker you are protecting against ranging from a curious kid to a well funded government.
Depending on how hard you want to make it, just hash all filenames so people can't see them. if thats too easy encrypt them ... I have an answer here on SO that details how to do this
I'm new to iOS development and working on a small iOS mobile app that stores sensitive information of users. Initially I thought of using custom AES encryption to encrypt/decrypt all the data. I also want the encrypted data to be synced with iCloud. After reading more I came to know from iPhone 3GS each device has a built-in AES-256 crypto engine. From the XCode, I observed that I can turn on an option called "Data Protection" for the mobile app to secure data. Based on my analysis I've below questions:
To use data protection for iPhone 3GS (uses iOS 6.1) do I need to set passcode?
Without setting passcode for the device how can I use the built-in crypto engine to encrypt my data?
The information are very sensitive and so in this case do I need to implement custom encryption?
RNCryptor is very useful, but it's basically just a wrapper for Apple's own CommonCrypto functionality (that makes implementing it pretty easy). It's useful if you want to encrypt data on the device that even the user cannot get ahold of.
Regarding your specific questions:
Data protection encrypts your app data using Apple's device-level encryption (you do not password protect it yourself). This has its uses - it will keep a 3rd party from being able to access data on a device if they are unable to unlock it - but does not prevent (for example) a user from getting access to data on their an unlocked device. Using RNCryptor and CommonCrypto which it is built upon you can AES256 encrypt content using a password of your choosing.
Apple details this here. Basically, from the end user's perspective they just set a password for their device as normal. You do not use a password of your own choosing.
You can set this up for your app using the following instructions:
https://developer.apple.com/library/ios/documentation/IDEs/Conceptual/AppDistributionGuide/AddingCapabilities/AddingCapabilities.html#//apple_ref/doc/uid/TP40012582-CH26-SW30
This depends on how sensitive the data is and what threats you foresee (Who are you trying to keep it away from? Are there any laws/regulations you intend to comply with? How much work do you want to take upon yourself to protect this data?). There are a lot of trade-offs and caveats that can apply in certain situations.
If you have a small amount of data, you might consider just storing it in the iOS keychain. Otherwise, I'd recommend giving RNCryptor a try. It's fairly easy to integrate.
I hope this helps.
UPDATE: Another thing to consider... There are potential export control ramifications that might come up if you implement your own encryption, even using RNCryptor/CommonCrypto. Depending on how much paperwork and/or delay you're willing to deal with, this may influence your decision. You can learn more about this from Apple's site, here:
https://itunesconnect.apple.com/WebObjects/iTunesConnect.woa/wo/20.0.0.13.7.2.7.9.3.1.2.3.3.1.5.7.1
This really depends on how many scenarios you are trying to protect against. Pretty much any scenario you can possibly create will be broken given enough time and effort. However to address a few points:
1) Yes you need to set a passcode for this feature to become active.
2) You can make use of the CommonCrypto library (or a wrapper around it like RNCryptor)
3) This is a bad idea for the simple reason that developing a secure algorithm is insanely hard. The slightest flaw will leak out all of the data and people have devoted years of their lives to sniffing out these flaws (although I may have misunderstood what you meant by "custom encryption")
If you want to be as secure as possible you will have to do this: Send your file to a server for processing (via HTTPS). It is much harder to hack into a server then it is to hack into an iOS application. If you simply use RNCryptor it is pretty trivial to rip apart the app looking for the password, or how you obtain the password. Basically if the app can do it then BlackHat can do it too.
EDIT I forgot about one thing! If you generate a random password for each install and store it in the keychain then this will help, but it is not foolproof (There is a small chance that the iOS keychain contents can be retrieved from a jailbroken device, especially if the user has a week passcode). However this will make the user's data non-recoverable if they wipe the OS for any reason.
very very very simple : https://github.com/RNCryptor/RNCryptor
I was used it for a chat application it so good.
I have two iPad apps, one which downloads data from a server and stores it on the iPad and another one (the main app) which uses the data later.
(It would make sense to combine the two but it's a client requirement)
But I see no way to share the data between the two apps.
I have heard there are ways to do it using:
Custom URL Schemes
Document Support on iPad Devices
UIPasteboard
But I cannot find any thing explaining how to use any of these effectively.
Can anyone point me in the right direction.
Just to clarify:
It is an iPad only app
Both apps will not run at the same time
Basically I need to access the documents or caches folder of one app from another
Using iCloud or any other third part service is not possible
It would be great if I could make the downloader app into a sort of configuration page for the main app (if it is even possible)
So keeping these in mind which one would be the most suitable?
This link at github may be useful... Looks like someone has already made a file manager, using these elements you may be able to do what you are looking for. But as far as I know, your app is extremely sandboxed and does not really interact with other apps/the file system very much at all (Apple is very limiting that way)
EDIT
this post seems to have the explanations of local data sharing methods you were looking for. None of the methods in this post requires any connectivity, just a device and 2 apps :) Good luck!