Feeds

How gizmo maker's hack outflanked copyright trolls

Chumby NeTV: A triumph for mankind

Gartner critical capabilities for enterprise endpoint backup

When the master encryption key locking down millions of Blu-ray players and set-top boxes was mysteriously leaked last year, Hollywood moguls worried their precious high-definition movies would face a new flurry of piracy.

Instead, it spawned the Chumby NeTV, a tiny, Wi-Fi-connected box that sits between a television and a set-top box or DVD player so email alerts, Tweets and other internet content are scrolled across the bottom of the screen – all without interrupting the flow of the video.

Making the NeTV break into the encrypted video stream passing through an HDMI cable required the elite hacking skills of Bunnie Huang, an engineer and co-founder of Chumby, the maker of net-connected alarm clocks that display weather forecasts, news headlines, and other internet content. Using the leaked master key at the heart of the HDCP, or high-bandwidth digital content protection, encryption scheme to modify the content was clever enough. Doing it without violating draconian copyright laws was nothing short of brilliant.

picture of Chumby NeTV

The Chumby NeTV in all its glory

That's because HDCP was created by Intel for the express purpose of thwarting piracy by restricting access to video passing between set-top boxes and TVs. It establishes a secret key that's unique to each pair of devices, creating a barrier for would-be pirates out to capture and copy the high-definition content. Tampering with this scheme runs the risk of violating the Digital Millennium Copyright Act, a law that carries stiff criminal and civil penalties for circumventing technology intended to prevent access to copyrighted material.

Ignorance is bliss

Faced with the challenge of crashing the party that only HDCP-compliant devices can join without running afoul of the DMCA, Huang employed the leaked master key in a way that allows the Chumby NeTV to use the shared secret key to inject Tweets and other content into the encrypted stream without decrypting the restricted video. His device intentionally remains oblivious to the protected work, a distinction he believes keeps it from violating the law's anti-circumvention provisions.

“It's important to note that nowhere in the pipelines is the video data decrypted,” Huang wrote in an email to The Register. “We don't use the master key to break any locks, or circumvent any copyright protection. We use it to enable interoperability and we do so without ever decrypting the source data: encrypted pixels are just replaced with different encrypted pixels.”

Huang's claims have been confirmed by two experts.

“What's interesting here is that although the device does have the keys needed to do decryption, it isn't actually doing that,” Keith Irwin, a professor of computer science at Winston-Salem State University in North Carolina, wrote in an email. “A conceptually simple means of modifying encrypted video would be to have the NeTV decrypt the video signal from the video device, modify it, then re-encrypt it. However, this isn't what the NeTV does.”

Cryptographer Nate Lawson, who heads the Root Labs security consultancy, has analyzed the open-source code that runs the NeTV and provides an analysis here.

Boost IT visibility and business value

More from The Register

next story
Kate Bush: Don't make me HAVE CONTACT with your iPHONE
Can't face sea of wobbling fondle implements. What happened to lighters, eh?
The agony and ecstasy of SteamOS: WHERE ARE MY GAMES?
And yes it does need a fat HDD (or SSD, it's cool with either)
Apple takes blade to 13-inch MacBook Pro with Retina display
Shaves price, not screen on mid-2014 model
iPhone 6 flip tip slips in Aussie's clip: Apple's 'reversible USB' leaks
New plug not compatible with official Type-C, according to fresh rumors
Steve Jobs had BETTER BALLS than Atari, says Apple mouse designer
Xerox? Pff, not even in the same league as His Jobsiness
TV transport tech, part 1: From server to sofa at the touch of a button
You won't believe how much goes into today's telly tech
Apple analyst: fruity firm set to shift 75 million iPhones
We'll have some of whatever he's having please
Apple to build WORLD'S BIGGEST iStore in Dubai
It's not the size of your shiny-shiny...
NVIDIA claims first 64-bit ARMv8 SoC for Androids
Mile-High 'Denver' Tegra K1 successor said to rival PC performance
prev story

Whitepapers

5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Rethinking backup and recovery in the modern data center
Combining intelligence, operational analytics, and automation to enable efficient, data-driven IT organizations using the HP ABR approach.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.