Anti-snooping operating system close to launch (developed to defeat Brit snooping laws)

New Scientist ^ | May 28, 2002

[John Jorsett]

Computer activists in Britain are close to completing an operating system that could undermine government efforts to the wiretap the internet. The UK Home Office has condemned the project as potentially providing a new tool for criminals.

Electronic communications can be kept private using encryption. But new UK legislation will soon give law enforcers the right to demand encryption keys from anyone suspected of illegal activity.

The Regulation of Investigatory Powers Act (RIPA) was introduced to update UK surveillance laws to include electronic communications. But privacy campaigners say it gives too much power to law enforcers and permits intrusive eavesdropping.

Peter Fairbrother, a mathematician and computer enthusiast, is programming the new operating system, called M-o-o-t. "It is aimed at anybody who's concerned about the government being nosey," he says.

Remote storage

M-o-o-t aims to beat RIPA powers by storing encryption keys and other data overseas, beyond the reach of investigators. No data will be stored on the computer's hardware.

Documents and email messages will be kept on servers outside the UK government's jurisdiction. Communication with these servers will be secured by encryption.

It will be possible to store files on any server that allows encrypted File Transfer Protocol (secure FTP) access. It will even be possible to share files between different servers, meaning that if one server were compromised, this would still not provide a complete file.

M-o-o-t will be almost entirely contained on a CD that will run on most PCs and Macintosh computers. The CD must be placed in a computer at start up and will then load up a graphical user interface, as well as a number of applications including an email client and a word processor. Fairbrother says the system aims to make it easy for anyone to use the suite of tried and tested cryptographic protocols that M-o-o-t combines.

Criminal tool

A spokeswoman for the Home Office dismissed privacy concerns over RIPA and warned that the system could provide criminals with a new tool: "This particular technology could provide the criminally inclined with a tool to further their criminal intent."

She told New Scientist: "Such a device in the wrong hands will do far more to infringe the human rights of innumerable potential victims than a regulated and inspected process such as RIPA could ever allow."

Fairbrother admits that the M-o-o-t might be used by criminals but says there are already more complicated tools available for determined lawbreakers. "The benefits far outweigh the problems," he says.

Master keys

Communication will only be possible with other M-o-o-t users using keys that expire after a single use. "Master" encryption keys will be kept on the remote servers in a format that makes it impossible to distinguish them from random data without the correct password.

This is possible using the Steganographic File System developed by researchers at the University of Cambridge. It stores all data as apparently random information.

"M-o-o-t sounds like a great idea," says Bruce Schneier, security expert and head of US company Counterpane Security. But he adds that extensive testing will be needed to ensure there are no software bugs: "Like any security technology, if you rely on it and it has flaws then you don't have the security you rely on."

RIPA, introduced in July 2000, allows UK police to intercept electronic communications using equipment installed at ISPs. When part three of RIPA is brought into power later in 2002, police will also be able to demand access to message encryption keys. Those who fail to hand over their keys could face a prison sentence.

Fairbrother says a version of M-o-o-t should be ready for testing in the next two weeks. The final product ought to be ready for the introduction of part three of RIPA, he adds.

[altair]

But all codes are eventually suceptible to brute force attacks.

You mean ciphers not codes. The point of cryptography is to make the expense of breaking the cipher greater than the amount of time the data has to be kept secret. For example the message "The suicide bombing starts in two hours Abdul" doesn't need to be kept secret as would a message planning something six months in the future.

[Redcloak]

Exactly. Encryption more often works by making the information stale by the time an adversary cracks it. This is seen in the VENONA messages Doctor Stochastic mentioned earlier. The Soviets were using one time pads to encrypt their messages. When they did it properly, it made the transmissions virtually impossible to read. But there were sometimes errors in the handling of the code sheets. This allowed the US and the UK to eventually read some of the messages, though years later. The content of any given message was, of course, beyond stale; but, there were some items that weren't out of date. The Soviets, thinking that the code was unbreakable, used the same covernames for years. Traffic analysis and the like allowed the US and UK to identify many of the Soviet agents mentioned. That information hadn't gone stale by the time the messages were cracked! Among the agents who's codenames were uncovered were Julius and Ethel Rosenberg.

The NSA's VENONA pages are a facinating read.