Jay Freeman (saurik)

Truly, jailbreaking should have stopped during the iOS 9 era, if not before; there is a reason essentially all of the reasonable developers left long ago and the community is largely now run by bullies. Everything that we do now just digs jailbreaking a deeper hole, full of fail.

In the mean time, I owe nobody anything and nothing I have would help anyone anyway (and particularly won't help anyone trying to support A12). I really wish everyone would just forget Cydia exists and move on with their lives; anything would be better than dealing with all this.

_If_ (yes: "if") I ever release A12 Substrate, it will not only be because I found a good way to achieve the goal that I consider "stable", but it will also be because I have, at least momentarily, come to enjoy the process of working on it again; that might _never_ come to pass.

This community operates under a broken concept of software that "anyone can update anything": no, if you are able to update something like Substrate, you can also rewrite it from scratch: jailbreaks and code injection tools are the result of hard research, not engineering effort.

FWIW, it is entirely possible that someone, using techniques I find "sloppy"--the kind of stuff that led to the iOS 11 stability issues (lots of kernel data patches to do stuff like mark processes as being actively debugged) can make A12 work easily--_I_ have no interest in that.

It is absolutely ludicrous to me that people are assuming that I would do this work _at all_ much less that I should _already have finished it_... "best case" I would never have expected to have had this done by now, as I honestly think this will be more than three weeks of work!

In particular, harassing me and everyone around me via every communication channel you can figure out to contact me is _not_ going to make me somehow care _more_ about doing this: all you are doing is making me deeply regret having returned. I gain nothing from doing any of this.

Even if I did, to be very frank about it: I find working on stuff for jailbreaking neither important (as I used to for the large, stable, untethered jailbreaks, with the goal of fighting copyright law: an era that is long over) nor fun (due to the horrible developer toxicity) :/.

San Bingner, using the awesome emulator environment from @CorelliumHQ, helped me verify my guesses here were correct (debugging into a call to pmap_cs_associate), but I just don't have the time right now to spend reverse engineering and attempting to understand this new logic :(.

For A12, it (surprisingly to me) turned out Pointer Authentication Codes were not a problem; however, Apple built a new layer of codesign--"physical map codesign" (pmap_cs_*, largely missing from the XNU codebase)--as part of their "Page Protection Layer". http://newosxbook.com/articles/CasaDePPL.html …

So far, I've only had a few days to work on A12 Substrate (something I couldn't even start doing until a few weeks ago, when I was given the first jailbreak build useful for testing with). I do not understand why anyone thinks I am able to spend all of my time on this anymore :(.

The reason jailbreaks end up getting built surrounding it is not because "it has taken over functionality the jailbreak somehow should do"; it is because "it turns out that most of the stuff that the jailbreak was doing was not only unnecessary, but actually somewhat harmful" :/.

I do provide a way for jailbreaks to "slip in" kernel patches (what some people call "unrestrict"); nothing critical relies on this: these are only for sandbox backwards compatibility and to make setuid work. I do not like _any_ of these patches and never used them on my devices.

When substrated starts, it gives itself TF_PLATFORM; after that, everything it does is "mach virtual memory sleight of hand". The exact same architecture is used by new versions of Substrate on old versions of iOS: the daemon is largely required to act as a vnode cache for hooks.

Anyone claiming "substrated handles kernel patches" has no clue what they are talking about: the reason I disagreed with jailbreakd was because it entrenched specific and _pervasive_ kernel data patches to do something as basic as code injection; Substrate doesn't do any of that.

Honestly, I am not sure Substrate for iOS 11 was a "healthy" achievement; I still enjoy working on Impactor (and have some major updates that I want to release), but it just doesn't seem possible anymore to have fun on Substrate :(. That said, I _am_ quite proud of its stability.

Yet, in October of 2018, when I was contacted by Sam Bingner--someone I find reasonable--saying Substitute was never stable and suggesting he could offload a lot of the pain I didn't want to deal with (including "dealing with other people") so I could release Substrate, I agreed.

So, for the rest of 2018--when some users seem to think they were "waiting on me"?--_I'd moved on with my life_. I didn't work on jailbreaking or Substrate _at all_ for over half a year, and I didn't look at Twitter/reddit. The "old guard" developers were happy I finally escaped.

It was in this moment that I realized "there is no benefit to any of this--only pain--and it requires me to constantly have to interact with people who are frankly _horrible_"; I was particularly proud of myself for blowing off all of the toxic jailbreak people at DEFCON 2018 :|.

It maybe should be made more clear that, while I was actively killing myself--stealing time and racking up stress--to build a stable iOS 11 jailbreak for two or three months at the end of 2017 and beginning of 2018, I finally quit entirely in early 2018 due to developer toxicity.