Root for SM-T290 (tab a 8.0 2019)

[J.Michael]

Because I think @J.Michael is tensed from what I am doing , but I have no other options

You originally said something like "to avoid hurting the reputation of the company". I didn't understand that, either.

I'm not the least bit tense, I think you are wasting your time talking about somehow bypassing the DRM that was designed so that you would not be able to bypass it. You talk about finding keys; I think the keys may not exist on any device, they may be constructed from values harvested from the device. Even if you find a key, what encryption scheme are you going to apply?

I am more interested in your talk of downgrading. Not because I think it can be done, but because I would at least like to understand why you think it would help you. What are you wishing you could downgrade? At one time you talked about downgrading the bootloader. I thought that was to allow you to install Magisk. What then? How would having Magisk help you?

Your most recent description of your problem was that the company that provides access to the video files wanted more money to continue your access. What do you imagine is going to restore your access without paying them?

 

[LUCID_DREE]

You originally said something like "to avoid hurting the reputation of the company". I didn't understand that, either.

I'm not the least bit tense, I think you are wasting your time talking about somehow bypassing the DRM that was designed so that you would not be able to bypass it. You talk about finding keys; I think the keys may not exist on any device, they may be constructed from values harvested from the device. Even if you find a key, what encryption scheme are you going to apply?

I am more interested in your talk of downgrading. Not because I think it can be done, but because I would at least like to understand why you think it would help you. What are you wishing you could downgrade? At one time you talked about downgrading the bootloader. I thought that was to allow you to install Magisk. What then? How would having Magisk help you?

Your most recent description of your problem was that the company that provides access to the video files wanted more money to continue your access. What do you imagine is going to restore your access without paying them?

So many questions, let me answer consecutively.

1) I think I didn't say 'reputation' but 'business', because you saw me in a negative light and said that it's done to hide from people like 'you'

2) I know that about DRM, I don't need to decrypt it , I just need to place the correct file storing the DRM at the correct place, but now I understand that the process will be very long so ...

3)You are more interested in Downgrade, I am too. Then I would not install magisk as you said. I would just flash twrp then restore the twrp backup , then I would 'get set go' with my study

What do you you think ? It's ok now?

 

[J.Michael]

So many questions, let me answer consecutively.

1) I think I didn't say 'reputation' but 'business', because you saw me in a negative light and said that it's done to hide from people like 'you'

2) I know that about DRM, I don't need to decrypt it , I just need to place the correct file storing the DRM at the correct place, but now I understand that the process will be very long so ...

3)You are more interested in Downgrade, I am too. Then I would not install magisk as you said. I would just flash twrp then restore the twrp backup , then I would 'get set go' with my study

What do you you think ? It's ok now?

Not negative. Just, if you are trying to get around DRM, then you are one of the people DRM is trying to thwart. You could be right, they could have been lazy or stupid. If you have the source for the program that displays a file, you might be able to figure out where all the pieces are hidden, and how to use them.

I do not think you will be able to downgrade the bootloader. In principle, you can open the box and forcibly write what you want to the memory. In practice, this would require skill, and probably equipment that costs more than the ransom.

Could you explain again what happened that suddenly denied you access to your saved videos? What does upgrading the bootloader have to do with the process?

Why are these videos so important? Isn't this information available elsewhere? Another lecture series, a textbook? At worst, a fellow student who will let you set up a camera to record his tablet playing the videos?

 

[LUCID_DREE]

Not negative. Just, if you are trying to get around DRM, then you are one of the people DRM is trying to thwart. You could be right, they could have been lazy or stupid. If you have the source for the program that displays a file, you might be able to figure out where all the pieces are hidden, and how to use them.

I do not think you will be able to downgrade the bootloader. In principle, you can open the box and forcibly write what you want to the memory. In practice, this would require skill, and probably equipment that costs more than the ransom.

Could you explain again what happened that suddenly denied you access to your saved videos? What does upgrading the bootloader have to do with the process?

Why are these videos so important? Isn't this information available elsewhere? Another lecture series, a textbook? At worst, a fellow student who will let you set up a camera to record his tablet playing the videos?

I saved 'encrypted drm videos' and the 'drm license authorization' to run those videos which are saved in the twrp backup ,which when restored on sm-t290 has 'drm license authorization' again available to android os and then i run those encrypted drm videos from usb otg, which are then decrypted by the android os.This implementation is not often done ,its rare , so there is no surprise that you are having trouble understanding what i am trying to achieve, by either downgrading, finding drm keys, or just restoring the backup on an android emulator(best option,if possible).

 

[LUCID_DREE]

Thats why i told that just searching among files from data partition will not help as it requires that the android os saved in that state to actually be running to even decrypt my videos in realtime while playing them , else it will not be posssible even if i just straightaway run those encrypted videos, they will not play at all. And finally to restore that twrp backup , i need to overcome samsung's restriction which has become a new and big hurdle, to either downgrade or upgrade to a version which allows twrp booting and doesnt show 'secure check fail: recovery.img' after flashing twrp.img and booting to recovery.

 

[LUCID_DREE]

its Important because these lectures are for cracking probably the world's toughest exam. And yes i will not get the info anywhere else nor in any textbooks thats why i need these exact, and also because i have paid for it and dont want to lose it without completing it. These study lectures are only saved by me , no other student did that and for them the lectures video are long expired ,so no help there even at worst.

 

[Minionguyjpro]

its Important because these lectures are for cracking probably the world's toughest exam. And yes i will not get the info anywhere else nor in any textbooks thats why i need these exact, and also because i have paid for it and dont want to lose it without completing it. These study lectures are only saved by me , no other student did that and for them the lectures video are long expired ,so no help there even at worst.

Did you get any progress or did something?

 

[Minionguyjpro]

Hello @Talich52, would you be able to provide the boot.img file of this device to me? I am going to port the Renegade Project to this device. I just discovered it, looks pretty nice. It ports UEFI firmware to Android devices! I can also download the stock ROM, but I don't know how to get it from that and I switched to LineageOS, so that is also not the stock boot image I guess, plus Magisk inside it. Would be nice if someone can give it to me!

 

[J.Michael]

Hello @Talich52, would you be able to provide the boot.img file of this device to me? I am going to port the Renegade Project to this device. I just discovered it, looks pretty nice. It ports UEFI firmware to Android devices! I can also download the stock ROM, but I don't know how to get it from that and I switched to LineageOS, so that is also not the stock boot image I guess, plus Magisk inside it. Would be nice if someone can give it to me!

I don't know what constitutes "stock ROM" anymore, but when I got my tablet it was 2019, I found a zip file on some site (samfrew? sammobile?). Unpack the zip, it's full of tar files. The AP.tar contains, among others, "boot.img", so extract that:

tar xvf AP.tar boot.img

(If "tar tvf AP.tar" shows the file is named ".img.lz4", then you have to use that name when extracting. And maybe expand that, depending on what you want to do with it.

 

[Talich52]

Hello @Talich52, would you be able to provide the boot.img file of this device to me? I am going to port the Renegade Project to this device. I just discovered it, looks pretty nice. It ports UEFI firmware to Android devices! I can also download the stock ROM, but I don't know how to get it from that and I switched to LineageOS, so that is also not the stock boot image I guess, plus Magisk inside it. Would be nice if someone can give it to me!

No problem! However, from which firmware exactly is boot.img needed? This is the core and it is different on different versions of android and T290/T295 models.
The boot.img file itself is in the firmware AP file, but in the lz4 archive, which is unpacked by 7Zip Standart. And I first extract the boot.img.lz4 file from the AP firmware file using Total Commander.

 

[Minionguyjpro]

No problem! However, from which firmware exactly is boot.img needed? This is the core and it is different on different versions of android and T290/T295 models.
The boot.img file itself is in the firmware AP file, but in the lz4 archive, which is unpacked by 7Zip Standart. And I first extract the boot.img.lz4 file from the AP firmware file using Total Commander.

From the latest U3 version, NOT U4! And from the SM-T290, but I got it from my device backup already. However, I just game to the fact I need all type of drivers and files to build it for this device's Snapdragon 429. I don't know whether you can look into porting it? I don't know whether you are an expert at it. It would just be nice to have that UEFI firmware, to see Windows, Linux and Android running natively on the device! First would be files for the SDM429 (Qualcomm Snapdragon 429) needed, with like configurations and stuff for building.

 

[Talich52]

From the latest U3 version, NOT U4! And from the SM-T290, but I got it from my device backup already. However, I just game to the fact I need all type of drivers and files to build it for this device's Snapdragon 429. I don't know whether you can look into porting it? I don't know whether you are an expert at it. It would just be nice to have that UEFI firmware, to see Windows, Linux and Android running natively on the device! First would be files for the SDM429 (Qualcomm Snapdragon 429) needed, with like configurations and stuff for building.

The latest firmware with 3 bootloader is T290XXU3CVG3 11 android. Here is an archive with a folder where the stock kernel boot.img is located.
I can't help with the development part, I'm not a programmer, just a user with a lot of experience...