Hashed Keys

Please post here for issues related to UHD discs
Locked
mike admin
Posts: 4075
Joined: Wed Nov 26, 2008 2:26 am
Contact:

Hashed Keys

Post by mike admin » Sun Jan 14, 2018 9:26 pm

Starting from version 1.10.8 MakeMKV can open an UHD disc using a “friendly” drive, provided a decryption key is known for the disc.
Update: Starting from version 1.14.0 MakeMKV can read UHD discs using any BDXL-compatible LibreDrive drive - that includes most "official" and all "friendly" UHD drives.

MakeMKV contains no AACS2.0 keys, so it requires a disc key to be supplied by the user. From the very first days of blu-ray the de-facto standard for blu-ray disc key management was libaacs KEYDB.cfg file format. MakeMKV (as many other applications) can read key files in that format to decrypt regular and UHD blu-ray discs. Unfortunately, when this file format was defined almost 10 years ago, assumptions were made about AACS system that are no longer valid today.

Starting from version 1.10.9 MakeMKV supports additional key format, called “hashed keys”. This format is superior to KEYDB.cfg file format, as entries are smaller, have integrity checking, much faster to verify and have few other good properties. The downside is that this file format is MakeMKV-specific, no other software can read files in this format so far. The same key can always be encoded as KEYDB.cfg key or as a hashed key, it is just that the latter is more efficient. Because both KEYDB.cfg and hashed keys are text files, the rules to use them are same – just download the relevant text file and put it into MakeMKV data directory. Having a disc key (encoded as KEYDB.cfg or as hashed key) allows one to open the corresponding UHD disc in MakeMKV.

Now, thanks to few heroic individuals and a big magic crystal ball, keys for some UHD discs are available. The keyfile can be downloaded at link below . This keyfile includes all doom9 UHD keys as well, so this is the one ultimate file you have to put into MakeMKV data directory. As a reminder, if a disk key is not known then protected disc will fail to open. MakeMKV will save a disc dump in this case, called "AACS dump". Please send these dumps to svq@makemkv.com .

Edit: MakeMKV automatically downloads the latest hash key file as needed, provided you have "contact the web server" enabled in your preferences.

mike admin
Posts: 4075
Joined: Wed Nov 26, 2008 2:26 am
Contact:

1.12.0

Post by mike admin » Sun Feb 04, 2018 12:22 am

Important: All versions before 1.12.0 have various nasty bugs in code responsible for UHD AACS20 dump generation. Please switch to the latest version . If you ever sent UHD MKB20 dumps, never heard back, but your disc did not appear in hashed keys - that was probably due to these bugs. Please re-submit your dumps with latest version and make sure you are opening original disc, not a disc backup. The new dumps should be very small if dump was already submitted, only few kilobytes in size.

Starting from version 1.12.0 MakeMKV creates a file called _private_data.tar in program data directory. This is not a dump, do not share this file with anyone (this file contains no sensitive information, but nothing in it needs to be shared).

Locked