Timac

Swift has been announced at the WWDC 2014, more than 2 years ago. Most of the sample code projects from Apple are now written in Swift. But does Apple use Swift in iOS 10.1 and macOS 10.12.1?

Did you ever wonder why the Facebook.app for iOS is such a big download? This post tries to give some answers. The version 66.0 (released on 7 October 2016) was analyzed on an iPad Air 2 (64-bit).

In iOS 10 Apple added a new dedicated setting for Temperature Unit in the Settings.app under General > Language & Region > Temperature Unit . It lets you switch your preferred unit between Fahrenheit and Celsius:

In a previous post CryptedHelloWorld: App with encrypted mach-o sections, I created a simple macOS app CryptedHelloWorld with its (__TEXT, __text) section encrypted. The section is decrypted by a constructor function. This post explains how to dump the decrypted app. A common way is to attach the app with a debugger (GDB, LLDB) and manually dump the decrypted memory to disk.

Mail.app in macOS 10.11 and earlier used to check the plugins compatibility using the SupportedPluginCompatibilityUUIDs key in the plugin’s Info.plist. For example a Mail plugin would only be compatible with macOS 10.11.6 if its Info.plist contained the following:

In a previous post ( constructor and destructor attributes ), I described the constructor attribute and mentioned software protection as a possible use case: A constructor attribute could be used to implement a software protection. You could encrypt your executable with a custom encryption and use a constructor function to decrypt the binary just before it is loaded. In this post I describe such a protection with an example.

GCC (and Clang) supports constructor and destructor attributes: __attribute__((constructor)) __attribute__((destructor))

Until macOS 10.11.4 and iOS 9.3.1 CommonCrypto/corecrypto supported Blowfish operations with key sizes longer than 448 bits. Starting with macOS 10.11.5 and iOS 9.3.2 this is no longer the case: the minimum and maximum key sizes are now enforced (respectively kCCKeySizeMinBlowfish 8 bytes and kCCKeySizeMaxBlowfish 56 bytes).

The State Preservation and Restoration system is well documented here: Preserving Your App’s Visual Appearance Across Launches. But what is not well known is that there is a secret preference to enable debug logs.

Let’s say you want to have a different behavior in your app depending on whether you build it in Xcode or you perform an Archive. And you want this behavior to be done at compile time. Note that the use of different configurations is not what is wanted.