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Cambridge Breached the Great Firewall of China
Darren Rayes writes to mention a ZDNet article on Cambridge academics' claims that they have breached the great firewall of China. They also claim that by misusing the firewall they can launch DDoS attacks against IP addresses behind the wall. From the article: "The IDS uses a stateless server, which examines each data packet both going in and out of the firewall individually, unrelated to any previous request. By forging the source address of a packet containing a 'sensitive' keyword, people could trigger the firewall to block access between source and destination addresses for up to an hour at a time."
With enough people working on it, we can temporarily block the entire country from the rest of the Internet. How's that for a fourth of July?
What about those inside China using those exploits for legitimate ends?
Is Cambridge indirectly helping the Chinese government to fix firewall issues?
Are Cambridge researchers after fame at the expense of the freedom of the Chinese people?
Better they do it from the outside then the Chinese government find the guys doing it from the inside.
Weird, I didn't know there were many mongolians at cambridge...
Stateless != ruleless. For example, you could use OpenBSD's "pf" to create a stateless firewall that references an external rules file, then use a cron job to rewrite that rules file once an hour. That might be a pretty reasonable approach if you're filtering billions of packets per hour and can't afford to track state for each connection.
Dewey, what part of this looks like authorities should be involved?
I wonder what the chinese government would do if groups of individuals from around the world used techniques like this to DDoS the firewall. I highly doubt that they could get their population to accept them completely shutting off access to the outside world, and a stateful firewall would be considerably more expensive, assuming they wanted to keep their same (terrible) level of performance.
What does slashdot think about this?
As far as I understood it, the point is that the wall blocks out IPs outside of China that try to send "sensitive" data into China.
Not a big deal either. Just send the IP Address of any mailserver you want to protect with a packet containing something "sensitive".
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
DDoS is using multiple computers to "flood" a target off the Internet. This would be a plain DoS attack using a software weakness to deny service.
Chinese firewall is nothing - try getting through the Saudi firewall. As I understand it, the Chinese are at least a bit less modest about what is banned, so you should be able to at least get some legit porn sites through Chinese internet. However Saudi internet would block not just porn sites, but womens rights websites, womens magazines websites, even medical sites - anything that would display a photograph or illustration of a naked woman or man was stricly banned. Even it was just part of a human body, i.e. shoulders up.
It's not something that is trivial to fix. Others can do a better job of explaining why, but for now, suffice it to say that it'd require a significant effort on the part of the Chinese Gov't.
Maybe it can be fixed in The Great Firewall of China v2.0
[Fuck Beta]
o0t!
http://www.google.cn/search?q=Falun
Falun Gong Is a Cult
www.china-embassy.org
Research Society of Falun Dafa and the Falun Gong organization under its control are held to be illegal
english.people.com.cn
Fifteen Falun Gong Cult followers attempted to sabotage cable TV network equipment
app1.chinadaily.com.cn
southcn:Falun Gong Cult OUTLAWED
www.newsgd.com
Here we should point out that the banning of "Falun Gong" by the Chinese government is also part of
www.chinaembassycanada.org
Falun Gong Practitioner Not Sorry for Killing Father, Wife
news.xinhuanet.com
Now compare all that to
http://www.google.com/search?q=Falun
Now, if the Chinese Gov't is making Google filter based on English keywords, you think they're not going to do the same with their uber-firewall?
Many Chinese schools teach english. It isn't like they only speak various Chinese dialects over there.
[Fuck Beta]
o0t!
...half a dozen of the other.
Certainly TFA suggests that the DoS attack could be used against chinese government computers, but this could also be used against chinese citizens. An exploit is, after all, an exploit. So I would suggest that in the case of the DoS attack, reporting it to the appropriate people - in this case the Chinese authorities - was the right thing to do.
Unfortunately, in this case, the very flaw that allows a DoS against machines within China also permits those inside the firewall to ignore the resets sent back, so by reporting the DoS, they've also reported how the censorship can be circumvented. (or, by discovering the censorship circumvention they've unfortunately stumbled upon a DoS attack).
In this case, I really don't think that there is a One True Answer.
The ways of gods are mysteriously indistinguishable from chance.
Their research is concerned with DRM ass hat tactics and such...pity!
Well done on writting a 'how-to' on pointers to make the firewall better. Im sure people out there new these things, and used them to their advantage. Now all holes will be plugged and even more censorship will rein in China. You have now had your 15mins of fame.
This is the same old tired argument we hear here on Slashdot over and over again. Expose the flaws and you either 1) alert the hackers on how to expose them or 2) Allow the admins to patch them. It's funny how depending on your political ideology, people will swing either way. How about a consistent opinion in favor of revealing flaws? Those who favor security by obscurity deserve neither.
Me too, it was an incredible symbol. The story of one of the photographers who captured that image is pretty amazing as well.
I'm a nature photographer.
Go ahead, mod me down.
Couldn't the Chinese government view this as an act of terrorism? In the interest of national security the Chinese government will start an ambiguous "War on Terror" after the the US "War on Terror" and "War on Drugs" which are _also_ unwinnable and declared solely to keep the ruling party in power via fear.
Is it just me, or does it seem rather unkind to go about declaring, "Look at me! I just conducted a cyber-attack against China!" Hey, I'm no fan of China's government or censorship, and I am aware that China have tried to attack other countries' computers, but two wrongs don't make a right. Unless we're doing something defensive to ward off an attack from China, I see little point in taunting them and giving them reason to tighten security even further. It just doesn't seem right.
It appears the link to the source is missing - I first read about it last week on Schneiers blog, linking ot the original blog post found here:
o ring-the-great-firewall-of-china/
http://www.lightbluetouchpaper.org/2006/06/27/ign
And for all the details, the paper to be presented is here:
http://www.cl.cam.ac.uk/~rnc1/ignoring.pdf
I think the interesting thing is that by configuring our end to ignore the invalid resets from the Great Firewall of China we can aid the distribution of otherwise censored material.
DDoS attacks against the GFC seems not to be that easy, as the article mentions the GFC is not one giant router at the backbone, but rather smaller machines closer to the end stations - the firewall is distributed accross an unknown number of gateways.