[tpb]Important[/tpb]
This software is still in beta. It has been tested with various ASR binaries from iOS 4 to iOS 10 for both ARMv7 and ARMv7s devices. Though assumed to work with any iOS 4-10 ASR on these architectures, it is still possible that it is incompatible with some untested version. Feel free to send me bug reports and success stories:
- Use this Google form: https://goo.gl/forms/qu5bNEMCex3keW5E2
- Contact me directly on Reddit: https://reddit.com/user/gjest
I am especially interested in knowing if it works on 5.x and 7.x!

[tpb]What is this?[/tpb]
ASR or Apple System Restore is the component that creates and verifies the filesystem during an iOS restore. It is also responsible for checking the signature of the root filesystem image inside the firmware IPSW, and will abort the restore if it detects that the image has been tampered with. Tools like Odysseus depend on being able to update this image, which is the reason why firmware bundles contain ASR patches. These patches prevent ASR from aborting the restore when fed a custom root filesystem image, by creating a branch (jump) instruction from the error handler to the code that is executed when an image passes the signature verification.

Creating these ASR patches usually involves modifying the binary using a disassembler, updating its hashtables and generating a BSDIFF patch file, which is time consuming. Fortunately ASR contains strings that make it easy to locate the correct addresses, and this is where this tool comes in. From a given input ASR binary, it creates a patch that is ready to be included in a firmware bundle.

[tpb]Compatibility[/tpb]
Hosts OS:
- Mac OS X 10.4 (Intel; x86, x86_64)
- iOS (ARM; armv7, armv7s, arm64)
- Linux (Intel; x86, x86_64)
- FreeBSD (Intel; x86, x86_64)

ASR binary:
- ARMv7, ARMV7s
- iOS 4–10

[tpb]Download[/tpb]
asrpatch 1.0b (apple, linux, freebsd):
- Tar/gzip archive: https://files.fm/u/4ahxbfhf
- Direct bash command: http://pasted.co/da1a8db8

Please do not include these binaries in other program as long as this tool is in beta.

[tpb]Thanks to[/tpb]
- /u/haniag and /u/OothecaPickle for the technical discussions on bundle creation and for testing the tool
- /u/alitek12 for the re-restore bug that allows us to test the tool without risk, for answering my many questions on Reddit, and for making me aware of the possible incompatibility with 5.1.1