– fordi tiden kræver et MODSPIL

03. May 2007

HD-DVD-kryptering brudt: 09 f9 11 02 9d 74 e3 5b d8 41 56 c5 63 56 88 c0

 
Et eksempel på, hvorfor kopibeskyttelse er en fundamentalt fejlbehæftet teknologi:

Indholdet krypteres, men brugeren vil altid have adgang til såvel det krypterede indhold som den kode, der muliggør afspilningen.

Kopibeskyttelsen hviler altså alene på, at brugeren ikke undersøger sit eget udstyr nøjere.

Men nu er den hemmelige kode, der tillader "uautoriserede afspillere" - f.eks. et Linux-system - at kopiere og afspille det nye DVD-format, blevet lækket - og kan findes som "subject" for dette indlæg.

Læs mere hos computing.co.uk:

A digital rights management (DRM) licensing authority is strong-arming search firms, bloggers and open source advocates in a desperate attempt to stop the spread of a software key that disables copyright protection on Blu-ray and HD-DVD disks.

Copyright reform activist Cory Doctorow decided on Monday to remove the information from a group blog to which he contributes after receiving a cease-and-desist letter from the Advanced Access Content System Licensing Administrator (AACS-LA).

The AACS-LA is backed by technology vendors including IBM, Intel, Microsoft, Sony and Walt Disney, and oversees the Advanced Access Content System (AACS) DRM technology used on high-definition DVDs.

The so-called processing keys published on the blog let users disable the DRM that prevents users from copying the disks or playing them on unlicensed equipment or software.

Doctorow is not the first blogger to receive a legal order from the AACS-LA. Several other blogs have been ordered to remove references to the key as well as links to a forum where it was first disclosed.

The AACS-LA has even issued legal threats against Google.

The crack first surfaced in mid-February on a Doom 9 forum. In an act of defiance, numerous bloggers have posted the key on their websites or linked to the website detailing the original crack.

They also submitted the web pages to social news services such as Digg in an effort to spread the information to a wider audience.

Ultimately the AACS-LA campaign has achieved the direct opposite of its intention. Instead of stopping the crack from spreading, the moves have notified more people of its whereabouts and how to exploit it.

Kopibeskyttelse er i sidste ende en teknologi, der skyder såvel sig selv som brugerne i foden, hvorfor flere og flere nu taler imod det. Hvordan i alverden kan nogen finde på noget så tåbeligt som at bygge noget, de selv opfatter som en vigtig beskyttelsesmekanisme, på et tal som 09-f9-11-02-9d-74-e3-5b-d8-41-56-c5-63-56-88-c0?

Læs mere hos Defective By Design, og på stridens Wikipedia-side.

Update, 4. maj kl. 08:40:
Denne nøgle virker kun på HD-DVD'er fremstillet før maj 2007, da ovenstående nøgle nu er tilbagekaldt for nyere DVD'er. Ars Technica skriver om en ny metoder, der ikke kan tilbagekaldes, og konkluderer:
Although AACS has proven much more difficult to fully crack than the copy protection on regular DVDs, it is unlikely to remain only partially cracked for very long. The real problem with trying to create an "uncrackable" copy protection is that the media must come with the keys used to decrypt it somewhere on the device and the media itself. Hiding these keys in different places—security by obscurity—merely delays the inevitable. Of course, for the content providers, any delay is still better than no delay at all, so expect the battles between copy protection and hackers to continue.

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