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Japanese P2P Users Arrested, Creator Targeted
nutznboltz writes "According to a story on CNET Asia, two Japanese users of the Winny P2P application have been arrested for copyright violations, and the developer of the P2P software has also had his home searched by police. Winny was 'supposedly anonymous', and purported to be based on Freenet, although Freenet creator Ian Clarke is claiming that Winny is not really like Freenet, and that he's 'not concerned that the Japanese police have somehow found a way to compromise Freenet's security'."
Youre parser is broken. The first sentence can mean:
'Security is broken and I dont care'
or
'I dont care because security hasnt been broken'
His statement that FreeNet is not what the Japs were using indicates the second meaning is more probable.
**TODO** Steal someone elses sig.
I had to read through the U.S. copyright law stuff a week or so ago, so I have a minimal amount of knowledge on this (I am not a lawyer, of course). Copyright violation is a criminal offense sometimes for the distributor, if a minumum amount of retail value worth of goods (among one or two other conditions) can be proved to be willingly distributed. For the recipient, I think only civil law applies.
Since Winny is pretty much unknown outside Japan, here is some background information for slashdot readers: Winny is a P2P file sharing program created by a Japanese programmer, who still remains anonymous to this day. It came out two years ago as an attempt to share copyright-protected materials "safely" when somebody was arrested for using another P2P program (WinMX). Since the application was extremely well designed and almost anything is available on its network, from movies to software, it has become immensely popular in Japan, so much so that there are a dozen book available on how to use it and network traffic in the country was down 20% after the news of the arrest broke. As for the reasons why the police was able to identify those two people who were arrested, they used an extra bulletin board feature, which does not guarantee anonymity unlike its file transfer feature, to distribute a list of warez videos. Therefore, I don't think this news has anything to do with the validity of Freenet's technology, or with that of Winny's for that matter.
... another uninformed person getting modded as Insightful.
... and there are others.
Pray tell - how do you search the regular World Wide Web?
Via som sort of service that knows webcontent since it spidered it - right?
Guess what Dolphin's Freenet Index is
So, no - I know perfectly well what I'm talking about. Freenet is just as searchable as the World Wide Web. Exactly.
it's in my head
The speed of the legal system here is notoriously slow.
:)
And, I'm told, most people can escape imprisonment or heavy fining by just apologising well.
So, I'm not sure what kind of resolution the companies are expecting, but I'm sure it will be a long time til we hear anything
Jon Johansen did not break CSS, and it's not a hard crypto. He wrote the gui for an application using a normal decryption key. CSS _has_ been broken cryptogaphically, and has about 2^16 complexity. It's not even worth being called a crypto.
it's in my head
This is a complicated issue without a clear answer.
If you want to be theoretical, then yes, Freenet does not provide anywhere near "absolute" anonymity. In fact, it doesn't even provide the level of anonymity that is used when judging such things as anonymous remailers or mixnets.
Basically, Freenet purports to be "anonymous" because you files do not recide on the computer of the person who uploaded them, and because all downloads and uploads are chained and tunneled through each host involved in the transfer. That means that the host you download a Freenet document from just knows it got it from some other node, which got it from some other node, which got it through some other node, all the way back to the person who uploaded it. It certainly makes tracking the people upload and download things more difficult then on networks like Kazaa (where it is, as we have seen, trivial) but in theory, and with enough resources, it is of course not impossible.
It should be noted what Freenet does NOT provide however. Freenet does do what the serious mixnets reffer to as "Onion routing", which basically means that the message is wrapped in an onion of cryptographic layers, which are pealed off at every step. The idea behind this is only the very last node can see contents of the message, and only the first knows it came from you (and none of the other nodes know anything except where the message came from and where it went).
If you request something from Freenet, your node will call up another node and ask it for that file - if that node is controlled by the Feds then you are busted. It is argued that there is plausible deniability, because it is possible that your node was not downloading the file because you asked for it, but simply forwarding it for somebody else. Given the state of the judicial process at the moment, I'm not terribly optimistic about this defense.
Freenet also doesn't protect (at least not very well) against traffic and timing analysis, allowing one to track down the author of something using the timing and amount of encrypted traffic that nodes exchange. I don't know of any case of traffic analysis having been used (except maybe on the NSA hyper-spook level), but it isn't impossible.
Another thing that Freenet does not "anonymise", and this is the most important IMO, is that you are running a node in the first place. Your Freenet node has to be public, so the feds could definitely "fish" the network for node addresses and start busting those who run them. Again there is an argument of deniability: you don't actually know what is in your nodes cache because it is encrypted, but again I don't have a lot of faith in this defense when the prosecutor will argue that you knowning acted in bad faith.
Regarding Winny, however, I think I agree with Ian. It seems doubtful that Winny works in the same manner as freenet, for the simple reason that Winny works, and well, freenet, umm, doesn't. Any time you try to put anonymity into something, useability IS going to take a hit, because trying to spread and bounce traffic necessarily hits performance. I have a very hard time believing that Japans most popular P2P network could be based on tunneling everything - purely for performance reasons.
(I have to run, so forgive typos and pitiful spelling errors.)
Freenet anonymity is relatively easy to attack. This is well known in the academic anonymity community. The fact that some do not admit such a possibility is disappointing.
For a good source of papers on anonymity, see:
http://www.freehaven.net/anonbib/
The way annoymity works is that files are stored in a "cache" in a scrambled format with filename concealed, even to the local user.
:)
Winny knows how to descramble the name and data, and it can search on the P2P network a specific file using its filename or MD5 checksum.
When a file is found, it is either downloaded directly or through another random user (think proxy).
Files goes into the cache either by local upload, by downloading a file (which Winny will descramble for you, leaving a copy in the cache), or by files passing through your node. It is then available for further download by other people.
This provides a kind of load-sharing where more popular a file is, it will be found in more people's cache and more easily available. Downloading from multiple sources is also possible.
You can find out who your immediate neighbour is, but he can claim he doesn't know what the content of his cache contains an infringing file, but of course this requires him to remove the original on his disk
To give an incentive to people to cache files, # of simultanenous downloads is limited to # of uploads+1 with a lower limit of 2.
It is a very convinent system because winny has a function that let you specifies search parameters and you can just leave it alone and it'll download everything that meets the parameters, meanwhile donating bandwidth and cache space to other people on the P2P network.
This model can be possible only because Winny is closed source. Cracks have both appeared for both the download limit and cache descrambling. It is easy to see widespread use of the cracks will compromise the model (less files to be found on the network).
Fortunately normally people don't care (it is just spare upload bandwidth and disk space, which broadband P2P users usually have surplus of).
Ever heard of onion routing? look it up.
Bascially, there is no source and destination, just a bunch of message passing between random nodes, the 'destination' just keeps and eye out for something that belongs to them. Put very basically. Theres a bunch of asymmetric crypto involved also. Look it up for more details.
I.O.U One Sig.
Also, it was a shock for many people because Mr. 47 only posts on an anonymous BBS system (think Anonymous Coward on slashdot) and IIRC never revealed his identity.
People are wondering how the police found out his identity. It has been speculated they might have gotten his IP from the BBS operator or from Geocities Japan where he keeps a page with the newest version for people to download.
Actually, just the size of the piece of content you are retreiving is very likely to tield enough information to identify exactly who retreived it, I'm afraid.
Pieces of data in Freenet are padded to the nearest exponent of two, so this particular attack would be pretty difficult.
>copying software isn't theft or crime, it's just copyright violation
It's a crime here in the UK. It was changed from a civil offense to a specific crime around about 1990.
That's not how onion routing works, actually. With onion routing the "server" is known and the client is unknown. The client creates an "onion" with encrypted routing information.
The communication is passed through a bunch of nodes each of which only know about the one before and after themselves.
In a p2p situation the clients sometimes act as servers so onion routing is a bit pointless by itself.
I don't think so. How could Freenet do proper onion routing when you can not determine what route it will take?
There was a negative missing there. Freenet does NOT do onion routing. Sorry (though I think it can be seen from the context what I intended.)
Actually, the defense is both good and bad - the problem lies in the HTL - Hops To Live. As it is (or at least was, when I tried to convince them it was a bad idea) the maximum HTL is 25 (in node, no matter what the program requests). That is, if you request/insert something with HTL 25, it's *your* request/insert, noone else's.
There is an added random factor to it, IIRC, but it isn't nearly high enough. In retrospect, I think that we should not have used HTL at all, but instead had a random probability of the request terminating at each node it reaches. The blame for it not being done this way lies mostly with me - I had an idea when we implemented the basic protocol that it should be very robust, thus every node keeps track of every request and times it out as soon as possible, and then something like HTL was needed.
Having seen how things turned out, if I was to go back today, I would made the protocol as lightweight, "fire and forget", and memoryless as possible instead. The usage pattern I imagined where users made a single request that had to succeed or fail correctly became "spam the network and hope for something" and the protocol was never designed for that.
It should be noted that the anonymity aspects of freenet take a hit from the routing problems in this case: Overload and lousy routing caused people to pump up the HTL, which caused us to limit it strictly to avoid and evil cycle (that wasn't avoided), which is why most people start with the highest permitted value today.
Also here, Freenet is pretty dumb in that it has a static 50 node limit by default. Once you've got 50 compromised nodes in contact with the target node, it's isolated from the network and you can see all requests/inserts it does. With at least some random factor, you would provide some uncertainty - do we control all nodes now, or are there still more? Can we *prove* these came from him?
I would say that the benefit of a random factor is dubious here. If you have the capacity to compromise all the nodes in the routing table, then you probably have the capacity to scan their traffic to see if they have other peers (I mean, how else did you find all their peers?)
They could not do a simple port scan, as you need the node's public key to get a response. However, you can listen on the network for those. Due to the state of the Freenet network, you need a certain inflow of new nodes, and so you also need to announce your node on the network. If you had a set of stable 24/7 static ip nodes to connect to, you wouldn't need to. However, since nearly all residential connections are semi-stable (cable/dsl), it is as it must be in order to keep the node functional.
"Silent Bob" as we called the idea of not responding until the key is seen, is in the protocol, but it is not, IIRC, the current default behavior of the node (for perfromance reasons). I don't agree that "a set of stable 24/7 static ip nodes" would be a good thing. The more static the network is, the more vulnerable.
The node probing defense also makes it impossible to know without actually securing the node - the node will sometimes pass the request, regardless of whether it has the data or not.
There is no defense against timing analysis of these responses. If the response is instantaneous, then you can be pretty sure the node contained the data before you probed it.
There is no defense against timing analysis of these responses. If the response is instantaneous, then you can be pretty sure the node contained the data before you probed it.
I think my analysis is almost the opposite. I wouldn't worry much about requesting or inserting data (if the network was working, I don't know w