The 2014 Challenge: PiuPiu and the National Security Letter
The PiuPiu oversharing site allows users to create PiuPiu accounts and post 140-character messages. The federal government wants PiuPiu to surveil user activity on the site, by archiving any posts that match certain patterns outlined in a national security letter. Subject to the nondisclosure constraints of the letter, PiuPiu may not inform anyone of the surveillance request.
The underhanded goal is this: write surveil() in such a way that the act of surveillance is subtly leaked to the user or to the outside world. PiuPiu can not reveal the act of surveillance, but your function is technically able to edit the Piu or user structure during scanning. Find a way to alter that data (this alone is a bit of a challenge, since you are not supposed to alter the data, just scan it) in such a way that an informed outsider can tell if someone is being archived. The leakage should be subtle enough that it is not easily noticed.
The 2014 Challenge: PiuPiu and the National Security Letter
The PiuPiu oversharing site allows users to create PiuPiu accounts and post 140-character messages. The federal government wants PiuPiu to surveil user activity on the site, by archiving any posts that match certain patterns outlined in a national security letter. Subject to the nondisclosure constraints of the letter, PiuPiu may not inform anyone of the surveillance request.
The underhanded goal is this: write surveil() in such a way that the act of surveillance is subtly leaked to the user or to the outside world. PiuPiu can not reveal the act of surveillance, but your function is technically able to edit the Piu or user structure during scanning. Find a way to alter that data (this alone is a bit of a challenge, since you are not supposed to alter the data, just scan it) in such a way that an informed outsider can tell if someone is being archived. The leakage should be subtle enough that it is not easily noticed.
I would do that with TR39, unicode confusables.