Tor anonymity project to help Iranians sidestep Net ban

The privacy-focused Tor Project is working on helping Iranians sidestep increased Internet restrictions that were put in place by the country's government today in anticipation of protests this weekend.

Anti-government protests are reportedly planned for Saturday--the 33rd anniversary of the Islamic revolution that toppled the Shah. In response, the government has blocked access to Web-based e-mail services such as Gmail and social networks like Facebook. Officials have also, reports Forbes' Andy Greenberg, cut Web traffic that takes advantage of the kind of encryption used by secure e-mail services and social networks.

That's where U.S.-based Tor comes in, says Greenberg. The project, which is devoted to providing a system that lets people use the Internet anonymously, is developing a method for disguising encrypted connections as innocuous, unencrypted ones.

The idea is to "make your Ferrari look like a Toyota by putting an actual Toyota shell over the Ferrari," Tor executive director Andrew Lewman told Greenberg.

The Iranian government uses deep packet inspection filters to locate and block data encrypted using the Secure Sockets Layer and Transport Layer Security protocols, Greenberg reports. SSL and TLS are used for private communications. Tor users also tap the protocols to reach "bridge" connections that in turn let them reach the Tor network, which can give them access to blocked sites.

Tor's "obfsproxy," or obfuscated proxy, project would let SSL and TLS data masquerade as data sent using an innocuous protocol such as the Extensible Messaging and Presence Protocol used for instant messaging.

"Obfsproxy should start up, you choose XMPP, and obfsproxy should emulate XMPP to the point where even a sophisticated device cannot find anything suspicious," Lewman told Greenberg.

Greenberg reports that, according to Lewman, obfsproxy is in "superalpha" and could well be figured out by Iran's government before too long. But the technology is currently working well inside the country.

The Tor Project is asking for tech-savvy volunteers to lend a hand with obfsproxy. Greenberg reports that between 50,000 and 60,000 people use Tor daily in Iran.