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Blu-ray key crack released

The HDCP master key, which was leaked last month and potentially renders the encryption system used on Blu-ray discs obsolete, has been implemented in software - despite Intel's claims that a hardware chip was more likely.

A pair of researchers from Stony Brook University, Rob Johnson and Mikhail Rubnich, have managed to implement the full HDCP encryption algorithm in software - meaning that it's possible, with the use of their code, to encode and decode HDCP-protected content, including Blu-ray discs, on any computer.

There are caveats aplenty, however. Despite using techniques such as bit-slicing to make the system run as fast as possible, the pair explain that, "The HDCP cipher is designed to be efficient when implemented in hardware, but it is terribly inefficient in software."

Based on benchmarks carried out on VGA-resolution content, the pair believe that real-time decryption of 1080p content from Blu-ray discs is feasible with their software - but estimate that it would take a "high-end 64-bit CPU" with at least two cores and around 1.6GB of RAM to achieve the required 30 frames per second.

The release of the code under an open-source licence is a blow for Intel, with company spokesman Tom Waldrop having previously stated his hope that a hardware implementation would be a more likely scenario - and one that would be significantly easier to stop being distributed.

Instead, the company now has to face the knowledge that a fully-working decryption system for its HDCP DRM algorithm is in the wild - and that work will doubtless continue to improve the software's performance.

So far, Waldrop hasn't confirmed whether Intel will be making good on its promise to bring its lawyers to bear on the researchers, following his warning that: "Should a circumvention device be created using this information [the HDCP master key], we would avail ourselves, as appropriate, of those [legal] remedies." monitors all leading technology stories and rounds them up to help you save time hunting them down.