engadget.com— We know that AACS, the DRM shared by HD DVD and Blu-ray, is touted as being practically unbreakable and impenetrable -- much like its predecessor CSS.
Jan 4, 2007View in Crawl 4
No one is trying to "crack" public-key crypto here. We're probably going to have to wait for a P=NP proof for that to happen anyway.They're just trying to crack THIS public-key crypto, and crypto algorithms are prone to flaws, bugs, and vulnerabilities just like all algorithms.
Why can't you simply watch them at full resolution on your monitor?The flag that is used to limit resolution of playback (ICT) is not currently enabled for any movies, nor is it likley to ever be since it would inconvenience too many people.
It doesn't work that way. I'm pretty sure AACS works something like this:1. The Video is encrypted via a secret key. This is the disk key. You must have this key to decode the disk's video stream. 2. The disk key is encrypted via each player's key and a copy of this encrypted version is added to the disk. Each disk has one copy of the encrypted disk key for every player that will ever exist. Assuming a few million of potential players (one player key per model?), this should only add up to a few MB of data.To revoke a key for a player, they just leave that player's encrypted disk key off of future disks. Existing disks that have the key will still work though.
Okay. It seems like nobody that is blogging the HDDVD crack can figure this out. To get the title keys in their decrypted form, muslix64 played the hddvd while hooked up to a vga monitor, then somehow grabbed the unencrypted key from RAM. Whatever software dvd player he used (on the forum) stored the unencrypted key somewhere in RAM when it was played, muslix64 just grabbed it somehow.at least i think...
@super:Don't underestimate the power of standards.I don't know if it is done this way, but it would be easy enough for the standard to be written such that the player has to accept key updates. This way, a full firmware update isn't required, just a small bit of memory in the system. The keys could be serialized (that is, older keys couldn't overwrite keys in the memory of the player if the keys in memory have a newer serial number) and would be raw, encrypted data that the player reads and then stores however it sees fit.
jimxugleJan 4, 2007
No... Content Scrambling system ( <a class="user" href="http://en.wikipedia.org/wiki/Content_Scramble_System">http://en.wikipedia.org/wiki/Content_Scramble_System</a> )It's the encryption system used on regular DVDs.
hoowahmanJan 4, 2007
Why are you people digging this guy down?
silverstrikeJan 4, 2007
No one is trying to "crack" public-key crypto here. We're probably going to have to wait for a P=NP proof for that to happen anyway.They're just trying to crack THIS public-key crypto, and crypto algorithms are prone to flaws, bugs, and vulnerabilities just like all algorithms.
superkendallJan 4, 2007
Why can't you simply watch them at full resolution on your monitor?The flag that is used to limit resolution of playback (ICT) is not currently enabled for any movies, nor is it likley to ever be since it would inconvenience too many people.
daridaveJan 4, 2007
NOT cool with me.I am hating this. I prefer HD DVD to Blu-Ray, I consider this terrible news.
mohaineJan 4, 2007
It doesn't work that way. I'm pretty sure AACS works something like this:1. The Video is encrypted via a secret key. This is the disk key. You must have this key to decode the disk's video stream. 2. The disk key is encrypted via each player's key and a copy of this encrypted version is added to the disk. Each disk has one copy of the encrypted disk key for every player that will ever exist. Assuming a few million of potential players (one player key per model?), this should only add up to a few MB of data.To revoke a key for a player, they just leave that player's encrypted disk key off of future disks. Existing disks that have the key will still work though.
Closed AccountJan 4, 2007
Okay. It seems like nobody that is blogging the HDDVD crack can figure this out. To get the title keys in their decrypted form, muslix64 played the hddvd while hooked up to a vga monitor, then somehow grabbed the unencrypted key from RAM. Whatever software dvd player he used (on the forum) stored the unencrypted key somewhere in RAM when it was played, muslix64 just grabbed it somehow.at least i think...
sanchoJan 4, 2007
@super:Don't underestimate the power of standards.I don't know if it is done this way, but it would be easy enough for the standard to be written such that the player has to accept key updates. This way, a full firmware update isn't required, just a small bit of memory in the system. The keys could be serialized (that is, older keys couldn't overwrite keys in the memory of the player if the keys in memory have a newer serial number) and would be raw, encrypted data that the player reads and then stores however it sees fit.