I have read that unlocking the bootloader wipes the decryption keys used to access the encrypted partition for proprietary Sony features.
Is there a way to backup these keys (DRM? ) and restore them back when reverting back to a stock Rom after installing a custom Rom?
How to backup keys
I belive that you need to be rooted
Yeah, some kind of temp root is required to run a script that backs up the TA partition.
I've also noticed that Sony does not have the Z3TC in the list of officially supported devices to unlock the bootloader.
Related
Hi guys,
a workmate has a htc one m8 and i flashed his device, but i had to read a lot of sh*t to understand how htc Roms for example work.
You need to flash the correct firmware to the ROM. (When you want a LP Rom, you need a LP Firmware from HTC).
Why is this not needed on sony devices? Is the firmware inside the ROM? I can freely flash from 4.4.2 to 5.0.1 to 5.1 and back to 4.4.4 without any problems.
Also we don't have any "radio roms" or "modems" i think?
How is this working at sony devices? Thanks for your answeres
1. xperias have something called drm keys which have some xperia functions work and also state your warrenty, unlocking your bootloader will wipe your drm keys (which are in your TA partition) and this will void your warrenty
2. xperias are quite easy
-unlock bootloader
-flash recovery
-flash kernel (thats supports fota (= recovery)
use that to flash any rom you want
or if you want to keep drm keys and all, downgrade, root, backup TA and upgrade and rooting just before
or if you want to keep it stock then downgrade, root and recovery then upgrade and flash root before upgrating recovery
Hi guys, so before I unlocked my bootloaer I rooted and backed up my TA partition... but now I'm trying to go back to stock sony from cm12 and restore TA backup
But the thing is, even after I flash stock KK and rooted it and restored my TA partition, my BL is still unlocked and in the Service menu > security , MARLIN, WIDEVINE and WMLA still has an unknown error...
Am I doing somethnig wrong? thx advance
hey all,
I'm on 23.1.A.0.690 fw with UB at the moment, and I'm planning to restore my DRM key (which I have a backup of) and re-lock the bootloader.
But I was wondering about :
What comes first, the re-locking or restoring the DRM keys
Will the re-locking process wipe the internal SD
Can the the process be done while being on Lollipop fw or should I downgrade to Kitkat?
Any information or insight is highly appreciated.
Thanks.
Before restoring your DRM keys you should make sure that your Kernel and FOTAKernel are both stock (do this by flashing just them with flashtool).
To answer your first question, when you restore the DRM keys it relocks the bootloader (which is why you must make sure your kernel and FOTAkernel are both stock).
The relocking process doesn't wipe the internal SD card.
DRM keys appear to be the same for your device across all firmwares. I have restored DRM keys taken from KitKat and restored them on LP with no problems.
So, I had my bootloader unlocked back when I was in kitkat (unsure whether I had version 4.4.2 or 4.4.4), but I had backed up my ta partition in case I wanted to relock the bootloader.
Fast forward to today, I am on lollipop (version 5.1.1) and I want to relock my bootloader. Note that I am on stock kernel.
Obviously enough, I have to restore my ta backup.
But I have some questions.
1)Do I have to downgrade to the android version the phone had when I took the ta backup, or I can simply flash the ta backup on my current android version?
2)During this procedure, does anything (such as data) get wiped?
3) Will I lose recovery during this procedure?
Mokiwipeout said:
So, I had my bootloader unlocked back when I was in kitkat (unsure whether I had version 4.4.2 or 4.4.4), but I had backed up my ta partition in case I wanted to relock the bootloader.
Fast forward to today, I am on lollipop (version 5.1.1) and I want to relock my bootloader. Note that I am on stock kernel.
Obviously enough, I have to restore my ta backup.
But I have some questions.
1)Do I have to downgrade to the android version the phone had when I took the ta backup, or I can simply flash the ta backup on my current android version?
2)During this procedure, does anything (such as data) get wiped?
3) Will I lose recovery during this procedure?
Click to expand...
Click to collapse
1. no
2. shouldent be
3. if you are using recovery for locked bootloader then no
A few days ago this was released: Universal TA partition backup
This means that we can retrieve the TA partition with a LOCKED bootloader!
In theory, then we can save the TA partition, root the M4 after UNLOCKING the bootloader, and then relock it by flashing the TA partition back.
If you were wondering about DM-verity, the M4 doesn't enforce that.
Someone confirm this?
Is no one seriously going to try this out? Fine I'll try it in my own time...
I tried it last week and it doesn't work, the backup file was 0bytes. Anyway you can make a TA backup using TA backup master with downgrading to Lollipop, root using the known exploit and then unlock the bootloader.
To root on MM you have to flash boot image, which requires unlocked BL and re-locking after that will result a boot-loop.
Check out the new version. It works now. TA Dumped ^^
The main problem is still there, flashing SuperSU from twrp doesn't work, so no way for re-locking the BL with root after that.