[liberationtech] Cryptocat Censored in China

[Joss Wright]

On Sat, Dec 22, 2012 at 09:58:50AM +0200, Nadim Kobeissi wrote:
> I would like to report that Cryptocat is now being censored in China. The
> URLs being 100% blocked are:
> 
> - Cryptocat Project Website: https://project.crypto.cat
> - Cryptocat Development Blog: https://blog.crypto.cat
> 
> We've tweeted an announcement and will probably follow with a
> (non-China-accessible :/) blog post:
> https://twitter.com/cryptocatapp/status/282393018693206016

Hi Nadim,

Any information on how the blocking is showing up? (DNS or IP based, for
example?)

Just out of curiosity I ran DNS queries for a set of about 200 servers
scattered across China, based on some other censorship probing I've been
doing. I haven't had time to go over the results in detail, but I'm
seeing roughly 40% returning (correct) IP addresses, 40% giving invalid
nameserver errors, with all other response types (timeouts, etc.)
scattered over the remaining 20%.

I haven't seen any IP misdirection, which has been the most common
response type for things blocked at the DNS level in my past
research.

I also haven't had a chance to check what sort of correlation there is
between the blog.crypto.cat and project.crypto.cat results. I'd be
interested to hear more, especially as the methods being used to block
things are apparently undergoing a bit of a shift at the moment.

Joss

-- 
Joss Wright | @JossWright
http://www.pseudonymity.net