How does DeUHD work?


#1

I know this one might be difficult to answer but i am really curious to know why some discs are supported and others not? What exactly does Arusoft do with the non-supported discs to make them become supported? Just curious that`s all and anyone feel free to speculate.


Titles Support List
#2

I firmly believe difficulty to decrypt varies greatly between discs.
It’s why there are certain older, popular discs that are still unsupported.

I think us continuing to send them the files THEY request is valuable.


#3

impossible to answer but possible to speculate

they have not cracked aacs 2.0. and i dont think aacs1.0 was even cracked. rather they have figured out a means to access the encryption keys to decrypt the disc. aacs 2.0 key mgmt is different than 1.0.

once you have the keys you need to write the code to decrypt the content.

my guess is still they found a hardware exploit for uhd drives that exposes the keys or makes it possible in some similar manner. similar to the fairly recent sacd hack for players using specific mediatek chipsets (oppo 103, 105, various pioneer players). it is not a crack. it is an exploit in the hardware to read the decrypted information and stream it to a program that writes it to disk.

this would explain why you have to own specific drives. i bet there is a common chipset in these drives.

all conjecture of course. but it works and 32 discs later i am satisfied


#4

Ok, interesting and that sounds reasonable given that only some drives are supported. But if it depends on the specific drives, doesn’t Arusoft need the physical disc to extract the keys from it?
How can they extract keys from a non-supported disc only by the files everyone here sends them?


#5

I believe they have access to some of the leaked master keys and they can inject them into whatever exploited hardware along with the unit keys we provide. Just a guess obviously.

Here is some fascinating reading courtesy of Wikileaks: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&cad=rja&uact=8&ved=0ahUKEwinyaPgp_bXAhXMx4MKHWmbDQUQFghWMAc&url=https%3A%2F%2Fwikileaks.org%2Fsony%2Fdocs%2F05%2Fdocs%2FAACS%2Fv2%2FAACS%202.0%20Architecture%20elements%20draft%2002_23_2014.pptx.pdf&usg=AOvVaw1l7CpYcs3WNF-FnxoG9lPH


#6

I’ve created a new topic with the discussion on how DeUHD works. I think it’s a very interesting subject and it would get easily buried in the Supported Titles List! I can always revert if there are issues with the decision, we’re here to help and not to boss you guys around :wink:


#7

Works for me. Thanks DoMiN8ToR.


#8

agreed. was a bit of a “thread hijak”

interesting doc you posted.

i’m not aware of any discs that require an online connection for initial playback, which was the old Divx model. I participated in as many counter-DIVX protests I could at the time in order for DVD to survive, and then was active in pushing BluRay as the standard over HDVD.

i wonder if the data that is downloaded when initially decrypting a supported disc is consistent across users and/or drives used to decrypt.

also suspect in some cases where we send files and support is quicly added that their database may simply be updating some primary keys based on what we send for the differences in disc titles (e.g. “SLOP_NA” for Secret Life of Pets, North America) but that the actual encryption keys are the same regardless of region. Basically they need some info from the disc in order to query their database for the correct keys to download. assuming we are downloading keys :wink: