Hey all,
I just thought I'd share and get feedback about some recent work from our team at Stony Brook University. I posted this to the tor-talk list earlier and it was suggested to x-post here, too.
Abstract: The Internet has become a critical communication infrastructure for citizens to organize protests and express dissatisfaction with their governments. This fact has not gone unnoticed, with governments clamping down on this medium via censorship, and circumvention researchers working tirelessly to stay one step ahead. In this paper, we explore a promising new avenue for covert channels: using video games as a cover protocol. The popularity of platforms like Steam have given rise to a rich population of video games for use as cover. The common properties of games in the same genre simplify the process of adapting channels to evade detection. We demonstrate the feasibility of this approach using two real time strategy games (including a popular closed-source game). We show how common properties of these games can be used to design a coding scheme to translate data into game commands in a way that is general across games and requires little per-game customizations. We evaluate the security of Castle by quantifying its resilience to a censor-adversary, its similarity to real game traffic, and its ability to avoid common pitfalls in covert channel design. We use our prototype to demonstrate that Castle can provide throughput which is amenable to transfer of textual data (\eg e-mail, short articles, etc.).
I thought this was a cool idea, and had a lot of fun exploring it. One of the key changes that Castle brings to the PT landscape is easy extensibility and large space diversity -- i.e., it takes very little skill and developer time to port Castle to any of 100's of existing (and perennially releasing) RTS games, in the event that it is detected and blocked for one game. Please check out the paper and feel free to post questions here, or email them to me.
Rishab