You are going to need some tools in order to get started with this tutorial. The basic requirement though is a jailbroken iOS device running iOS 5.0-10.2. Likewise, make sure that you have installed iFile and MTerminal. The said apps will be useful to navigate around the system.
Simply add https://coolstar.org/publicrepo/ on Cydia and download certain packages, such as BigBoss Recommended Tools, Darwin CC Tools, LLVM+Clang, iOS Toolchain, and CrashReporter. The said tools will help you compile the code that you make on-device and it can also be utilized in developing iOS tweaks and apps.
At the same time, you should require a Software Development Kit or SDK, which the recommended version is iPhoneOS8.1.sdk. However, you can also use a version that would appeal to you. The site https://sdks.website has a lot of SDK versions that you can download. Just move it to the /var directory found on your device. Alternatively, you can leave your SDK to /var/theos/sdks/ if you have the THEOS setup on your device.
You can write a short C program that would display a hello world type of code. You can do this inside the iFile by creating a new file named ‘hello.c’. Simply paste the code below.
The code presented will display a message to the user before it exits. Save the .c File and open up MTerminal, and login as root by typing ‘su’ and the default password ‘alpine’.
Type ‘cd’ to the directory path where your .c file was stored, for instance, /var/mobile/. Moreover, you are required to use the Clang compiler and type the following command: clang hello.c -isysroot /path/to/sdk/ -mno-thumb -o hello
After the compilation, use ‘ldid’ in order to fake the sign in the binary by typing ‘ldid –S hello’. At the same time, type the command line ‘./hello’ to execute the binary. By doing this, you will be able to build, compile, and execute your own C program. Using these codes should help you set up your iOS in preparation for exploit development practice.