Didn't even know there was one out there and was just messing around and lo and behold there was an update downloading. Managed to kill it through running processes.
Question: Will ATT push this download or do I have to go get it to get it. Not rooted or anything yet but I don't want that ability compromised. I'll root and use TiBu to freeze the app if ATT can just push this on me.
I wonder if geohot's S4 Active root will work on the new OTA? It would need to be modified slightly because his APK checks to make sure the phone is the Active.
Here's a flashable zip of the MF3 modem ONLY. The zip should work, but I can't attest to the anything that may happen to your device as a result of the new modem.
Gonna assume everyone has the common sense to read through this thread BEFORE flashing, as this kind of stuff can mess up your phone pretty bad if done wrong.
Nothing is "uncrackable", people. There might be some misunderstanding here about what it means to blow a qfuse/efuse. It's been stated around the forums plenty of times before, but usually only deep within Dev conversations about hacking bootloaders, etc.
If I'm wrong in any of this, please feel free to correct me (that's what the internet is for, right?).
It's simple - an e-fuse is designed to do one thing: increment. When the bootloader is flashed to a new major version (often correcting numerous exploits, along with some bug fixing or improvements), the manufacturer or carrier will often decide they don't want anyone going back to earlier versions. In the case of the S4 with KNOX expectations of security, this makes total sense (how could a government agency or large corporation guarantee that their employees are not rooting their phones and bypassing security measures set in place by the company? Or even malware that applies the root exploit for itself?).
When the newer firmware is flashed, the e-fuse gets incremented (to a "2" in this case, it appears). Any firmware with a "1" will be refused by Odin on the phone. These e-fuses are again designed to only increment, never decrement - meaning if you're at a "2", there's no hope that you can ever get your e-fuse back to a "1" again.
In terms of hacking, bootloaders, root, etc.: This just means that whatever exploits and bug fixes have been made are now permanent. That doesn't mean that new exploits cannot be made.
One of the biggest questions I will have: Does the refusal to apply an older firmware (through Odin) also imply the refusal to boot said firmware (if somehow loaded by another means - via dd or JTAG for example)?
I'm hoping to find out sometime this week.
EDIT/ADD:
And yes, jeboo is correct. They could always release a new firmware, and increment the e-fuse again to a "3" whilst still unlocking the bootloaders. The bootloaders are only "locked" because they are currently programmed not to load "whatever we want". Just remember the chain:
PBL -> SBL1 -> SBL2 -> SBL3 -> ABOOT. The PBL is physical and can't be changed without hardware modification. But the rest of those can be changed. Usually custom bootloaders would be loaded in the later stages (aboot for example). But with sbl2 and sbl3 checking for signatures and such, there's no hope to do this without bricking instantly. If AT&T were to push an unlocked version of SBL2 and SBL3 in a future patch, these new pieces of the bootloader could be designed to be successfully loaded by PBL/SB1, but also not check for signatures on ABOOT.
Complete! Uploading shortly. I will be starting a new thread with a full write-up on how to install MF3 on your own device while keeping your current recovery and rooting the new MF3. Also, I've zipped up my modified MF3 SecSettings.apk to remove SysScope. That means you'll have the option to get MF3 without the "Custom" status or logo.
(To those wondering if it is possible to root the new MF3 if you were forced to get it, I cannot help you, I'm sorry. The method involves simply flashing a zip from recovery. If you've taken the full, unaltered MF3 OTA update, you will notice you no longer have a custom recovery!)
I need to go upload a lot of files and finish the write-up. Once complete, I'll run my device through the instructions one last time as a final test.
As usual, "Stay tuned." I'll post a link her ein this thread to the new thread when it is created.
