How our tests are done

We have been detecting which websites are blocked in China since February this year. Using our tool and contributions from our visitors, we've created the most complete database anywhere of what's blocked by the so-called Great Firewall of China, including 2200+ blocked websites and 200+ blocked searches. But how accurate is our data?

When a website is tested, it's always done by comparing the results of trying to access it from A) a computer outside China and B) a computer inside China. This way, a website that is simply not working is not labelled as blocked. A website that works when accessed outside of China but fails when tested from inside China, on the other hand, will be labelled as blocked.

This makes our data more accurate, but not perfect. Another difficulty is that the Great Firewall often changes temporarily. A given website that was previously accessible may be blocked for, say, 20 minutes. The opposite is also true. Blocked websites are sometimes temporarily accessible. Examples include Facebook (March 28, April 25) and YouTube (July 31, Aug 15 etc).

To tackle this particular challenge, our scripts always re-run testing of a website once more, after it's status has changed. In most cases, temporary changes are quickly detected and the websites are labelled correctly again. In some cases, however, if the change lasts somewhat longer, it may take up to a week for our system to re-label the website correctly. So, for example, Paypal was tested to be blocked twice on Aug 22. It's now accessible again. But it will take several days before our system automatically tests it again. Meanwhile, it's labelled as blocked.

We are continously working to improve our system and to increase the accuracy of our data. Meanwhile, please pay attention to the history of tests of any given website you are looking up. That should give you a good idea of whether a website is always blocked, almost always blocked, sometimes blocked or always accessible.

And if you find any other glitches in our system, please let us know. Thanks for your support.

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Tue, Jul 05, 2016

GreatFire.org now testing VPN speed and stability in China

There is a commonly held belief in China that if you have a VPN that works then you should keep quiet about it. In terms of freedom of access to information, the problem with this approach is that access to knowledge suddenly is a secret. Today we are launching a project that we hope will destroy that model.

Our newest website, Circumvention Central (CC), aims to provide real-time information and data about circumvention solutions that work in China. Since 2011, we have been collecting data about blocked websites in China and now we will add data about the effectiveness of VPNs and other circumvention tools.

We are launching CC with four main objectives in mind.

Our first objective is to help to grow the number of Chinese who circumvent censorship restrictions in China. By sharing our information and data about these tools, we hope to show a wider audience which circumvention tools are working.

Our second objective is to improve the circumvention experience for users in China by bringing transparency to tool performance. We will measure these tools on speed (how quickly popular websites are loaded) and on stability (the extent to which popular websites load successfully).

Sat, May 07, 2016

The New York Times vs. The Chinese Authorities

Could the New York Times be setting the best path forward for news organizations in China?

Thu, Feb 18, 2016

From the desk of Lu Wei: Apple, encryption and China

Lu Wei, Director of the Cyberspace Administration of China, offers some friendly help to FBI Director James Comey.

Thu, Sep 24, 2015

Apple blocked CNNIC CA months after MITM attacks

In March of this year, Google found unauthorized digital certificates for several Google domains. The root certificate authority for these domains was the China Internet Network Information Center (CNNIC). CNNIC was controlled by the Chinese government through the Ministry of Industry and Information Technology and is now under the management of the Cyberspace Administration of China (CAC). CNNIC was recognized by all major browsers as a trusted Certificate Authority. If CNNIC signs a fake certificate used in a man-in-the-middle attack, no browser will warn of any unusual activity unless the certificate is pinned.

After Google found these unauthorized certificates, both Google and Firefox revoked its trust in CNNIC a few days later, a development we at GreatFire.org have adovacting for since 2013. Apple and Microsoft on the other hand, did not revoke their trust in CNNIC, nor did they make any announcements regarding the security compromise.

Wed, Sep 23, 2015

Malicious Xcode could spread via download manager Xunlei

What’s at stake?

We reported last week that popular Chinese iOS apps were compromised in an unprecedented malware attack. We discovered that the source of the infection was compromised copies of Xcode hosted on Baidu Pan. Apple has published an article urging developers to download Xcode directly from the Mac App Store, or from the Apple Developer website and validate signatures. We’ve now discovered that even if a developer uses a download link seemingly from Apple, he might still be possible to obtain a compromised copy of Xcode.

Please note that we do not have evidence that such attacks has happened. But it is an easy attack that anyone can implement.

How does it work?

This compromise happened because of Xunlei. Xunlei is the most popular download manager in China. Much of its popularity is due to the fact they can accelerate download speeds by pulling resources from other Xunlei users as well as cached copies on the Xunlei server. All of this, however, is invisible to users. Users can simply enter a regular http download address into Xunlei  download manager and the download will start. Chinese developers were using direct download addresses such as http://adcdownload.apple.com/Developer_Tools/Xcode_7/Xcode_7.dmg to download Xcode.

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