North Korea is a surveillance state propped up by a totalitarian government infamous for human rights abuses and a huge military that serves the elite while the poor are left to fight over scraps. Coincidently, that’s exactly what North Korea says about the United States.

There is one significant difference between the two countries: North Korea has developed its own operating system for its citizens, called Red Star OS. It’s an operating system based on Linux, but that has a few interesting features that allow Glorious Leader to take care of his citizens. A deep teardown of what has gone into the development of Red Star OS hasn’t been available until now, with [Florian Grunow] and [Niklaus Schiess]’s talk at the Chaos Communication Congress this week.

The first question anyone must ask when confronted with an operating system built by a country that doesn’t have much electricity is, “why?” This question can only be answered philosophically; the late Kim Jong-Il stressed the importance of North Korea developing “their own style” of programming, and not relying on western operating systems. Nearly everything in Red Star has been modified, with a custom browser called Naenara, a crypto tool, a clone of Open Office, a software manager, and a custom music composition tool. Red Star also had to have the look and feel of OS X; that is, after all, what Glorious Leader uses.

Red Star goes much deeper than custom browsers and a desktop theme. There are other, subtler components inside the OS. There is a program that verifies the integrity of the system by checking signatures of the custom files against a database. If a file has been tampered with, the system reboots. Since this tamper check runs on bootup, Red Star makes it nearly impossible to modify files for study. This is one of the big features designed into Red Star – system integrity is paramount.

There are other custom bits of software that hide files from the user even if they have root, and a ‘virus scanner’ that is anything but. This virus scanner checks documents for patterns that, when put through Google Translate, are strange, weird, and somewhat understandable. Phrases like, “punishment”, “hungry”, and “strike with fists” are detected in all documents, and depending on what the developers decide, these documents can be deleted on a whim.

While scanning a system for documents that contain non-approved speech is abhorrent enough, there’s another feature that would make any privacy advocate weep. Media files including DOCX, JPG, PNG, and AVI files are watermarked by every computer that opened the files. This allows anyone to track the origin of a file, with the obvious consequences to free speech that entails.

While most people in the US consider North Korea to be a technological backwater and oppressive regime, the features that make Red Star OS useful to the DPRK are impressive. The developers touched nearly everything in Red Star, and the features inside it are rather clever and make their style of surveillance very useful. They’re also doing this without any apparent backdoors or other spycraft; they’re putting all their surveillance out in the open for all to see, which is, perhaps, the best way to go about it.