nythepegasus / Sideloader

Sideload iOS apps. Even from Linux.

Sideloader

The missing open-source iOS sideloader.

Sideloader is an application made to install third-party applications on iOS devices.

You can see it as an open-source replacement of Cydia Impactor.

Currently only working on Linux (it was the priority since no easy alternatives exists).
Windows support is planned (it should not depend on iCloud!).
The CLI works too on all systems.

I tried to make the code as readable as possible, if you struggle to understand anything I am here to help!

Leave a star and a small tip if you feel like it! — more information at the end!

How to install

Currently, the only builds available can be downloaded through GitHub Actions.

On Linux, when it will be ready, it will be as simple as installing the Flatpak on your system, or wait for someone to package it for your distribution.

On Windows, it will get a GitHub Release with a simple executable to run.

Currently, Windows GUI is not working, and the CLI is pretty bare-bones.

Dependencies (runtime): libimobiledevice, libplist-2.X (I attempted to support both 2.2 and 2.3). OpenSSL is currently also needed, but I plan to remove that dependency as soon as possible (only networking is requiring it).

How do I build it myself?

Get a recent version ldc2 or dmd installed (an installation script is available on dlang.org). GNU D compiler won't compile that code (the cryptography libraries uses SIMD instructions that it can't compile yet).

How it works?

It works by fetching an iOS development certificate as Xcode would do if you were developing your own iOS application¹ and use it to deploy a third party application.

It does not require any Mac or Windows computer, nor any Apple software to be installed to work. It is just requiring libimobiledevice and libplist.

It is still requiring you to have an Apple account (which will play the role of the app developer to Apple), you can use any account for that, don't need to use your actual Apple ID used with your phone (I recommend making a burner Apple account, see SideStore wiki to have easy ways to do that, or on Linux, I'd recommend installing Apple Music on Waydroid).

Your credentials are only ever sent to Apple servers, and you can easily verify this!
In general, never trust anyone to handle your credentials, even more if it is in a closed-source obfuscated application (as-if there were something to hide there ^^).

Features

• Sideload
• iOS version range is unknown. 32-bit support is untested. Please report any issue here!!

A dedicated SideStore installer feature is planned with automated pairing file management.

Notes on platform support

Linux

Linux version currently only features a GTK frontend. I made one because I was already familiar with GTK+. I made it in plain code because I really dislike GTK Builder's XML.

Windows

Windows version uses a Win32 frontend. On Windows 11, it looks terrible. The current state of GUI libraries on Windows is rather unsatisfying: we have one old well-supported library across the major versions of Windows, Win32, the one I am using, and then we have a lot of unsuccessful attempts to supplant it, and finally we have WinUI 3, which looks good but has no bindings whatsoever (WinRT is supported in C# and C++ only, I would have to make the bindings myself, which I could do but would take some effort), and is not supported everywhere (Windows 10+ only). This is why I used DFL, which is a Windows Forms like wrapper of Win32 APIs.

Requirements: a USB muxer, which is generally iTunes or anything distributing AppleMobileDevice. netmuxd should work too if you can't install it for some reason. OpenSSL is also required for networking, unfortunately.

macOS

Only the CLI tool is available yet.

GUI support is planned but low-priority as macOS already has more tools to install and manage iOS apps.

Acknowledgements and references

• People on this thread: first cues on the authentication systems for both machines and accounts.
• All the people in the SideStore team: testing, help on the machine authentication.
• All the people in the AltStore team: help on the account auth, and 2FA (especially kabiroberai's code).
• zhlynn: for its code in zsign.
• indygreg: for its code in rcodesign.
• teryx: their article about code signature.
• Apple Music for Android libraries: giving the opportunity to make all of this work neatly!
• Apple's AuthKit and AuthKitWin: giving me the skeleton of the authentication requests directly.
• Probably a lot of people I missed!

If you like my software, consider starring or even better: sponsoring me :)

In late 2019, Cydia Impactor stopped working, and the underlying reason also affected some of my personal projects at the time. At this time, I decided to start the development of an alternative. I had no experience in reverse-engineering, or even just making complex request for authentication on a server. Making this project made me a better developer, but this was not easy to do.

While most Cydia Impactor alternatives benefited of some Apple software available on macOS or Windows, (and thus were able to hijack their libraries and reproduce their behaviour), Apple never released anything targeting the end-user on Linux.

I took 2 years to find a way to overcome the problem that encountered Cydia Impactor without resorting to reimplementing the full Windows API. I dedicated a lot of work on this software (alongside my studies).

That is why I am asking you - if you enjoyed my software and if you can afford it, to give me a small tip via GitHub Sponsors.

Footnotes

1. You may wonder if that would allow full iOS application development on Linux, and the answer is yes! You can compile a native iOS app on Linux with theos, and then package it into an ipa with PACKAGE_FORMAT = ipa to eventually install it with Sideloader on a real device (or maybe even an emulated one in the future!) and debug it (with idevicedebug or remote lldb). (TODO: add an option to add the entitlement for debugging) ↩