nicolodev

I'm having doubts about what you mean about "TEE", I suppose it's term for "trusted execution environment". I'm not sure about I might answer, and it's probable the right question to ask to Apple engineering. I think Apple can use the same technology they used for Apple Pay via the Secure Chip. I'm talking mainly about exchanging keys via servers, decryption and then serve the content via a sort of "frontend". I wish to know more about TEE to give you a more detailed answer.

EDIT: thinking about secure enclave.. maybe (still an hypothesis) the chip does not have the bandwidth to perform decryption just in time. Probably it's a huge cost for Apple to apply something like that.

Thanks for your feedback. As I previously said in another comment, the article was written in one go and I probably have missed the point of "be minimal in the description". I felt that readers should know a little bit more about obfuscations techniques, their use and why these are deployed into prod. While I am writing, I tend more to be "story-teller" to immerge readers into the flow, but I do admit this article is really difficult to read. I even deleted some paragraphs because it was going to be huge.

Thanks for your comment. This article was written in one go, and it could be way better than the actual state. However I do appreciate that you mean to consider my article as a nice example on how things work out in practice. Being a programmer and knowing a little bit of reverse engineering is important (well, I'm still a programmer too!). If you have any questions, please let me know.

Regarding the difficulty of learning material, I can feel you. It was the same for me when I started (I have a lot of stuff to dig into!), and it's still. Academy papers might be difficult to understand, but once you comprehend the formalisms it'll be easier. For sure, understanding the formal formulas is another challenge that I haven't resolved yet.

Thanks for submitting the article! Let me know if anyone has any questions. If you are wondering how Apple obfuscate its software, the answer is simple: they built some extensions for LLVM that applies code transformation directly to LLVM IR. LLVM IR is an intermediate language to represent the code that will be copied in binary.

Yeah, even LLVM is able to decode part of the obfuscated expression. Sometimes, it fails greatly printing out the obfuscated expression. There're several papers available and I'll write about it.

Example of output: https://github.com/seekbytes/pocket#example Mixed Boolean Arithmetic refers to expressions which include boolean, and arithmetic operations (AND, OR, XOR, PLUS, MINUS, MULTIPLY..). Let an expression be something like A + B. My tool applies some transformations to re-write this expression in more complex terms (such as ((A & B) + (A | B))).

Let me know if you have any questions!

Example of output: https://github.com/seekbytes/pocket#example

Mixed Boolean Arithmetic refers to expressions which include boolean, and arithmetic operations (AND, OR, XOR, PLUS, MINUS, MULTIPLY..). Let an expression be something like A + B. My tool applies some transformations to re-write this expression in more complex terms (such as ((A & B) + (A | B))).

Let me know if you have any questions!

I included an example for people that might not know what MBA expressions are: https://github.com/seekbytes/pocket#example

Github repository: https://github.com/seekbytes/pocket

Thanks, I re-submitted to HN to specify "Mixed Boolean Arithmetic Expressions" in the title

The repository for the tool I developed is https://github.com/seekbytes/pocket :) Enjoy it!

Thank you for the contribution! TIL :)

Thanks for your contribution. I just wanted to add some context for the problem of N items that share a median value and they want to reach independently all the same value. :) Thanks for the specification!