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Crypto Guru David Chaum's Private Communications Network Comes With a Backdoor (softpedia.com)
An anonymous reader writes: David Chaum, father of many encryption protocols, has revealed a new anonymity network concept called PrivaTegrity. Chaum, on who's work the Onion protocol was based, created a new encryption protocol that works as fast as I2P and the Onion-Tor combo, but also has better encryption. The only downside, according to an interview, is that he built a backdoor into the darn thing, just to please governments. He says that he's not going to use the backdoor unless to unmask crime on the Dark Web. Here's the research paper (if you can understand anything of it).
1. Is anyone going to trust something with a backdoor?
2. who's ?
When PrivaTegrity’s setup is complete, "Nine Server Administrators" in nine different countries would all need to cooperate to trace criminals within the network and decrypt their communications.
If you can trace criminals you can trace dissidents and political opponents. Anonymity is difficult enough without it being broken by design.
Just telling everyone your software has a backdoor is the same spending all of your development time masturbating. No-one is going to use this crap.
Is he claiming he found a way to safely have backdoored communications?
Not sure what "safely backdoored" means. The system is spread out amongst many different countries in such a way that many different governments must agree to use the back door. If the USA, the Netherlands, and Russia can agree, for example, then it is probably criminal investigation and not spying going on. I reviewed many of the early drafts of this paper. It's pretty cool.
Oh yes! The world will be a better place when governments are aided by secure communications developers in fighting crimes like apostasy, being gay, etc., and whatever new "crimes" might be defined out of thin air in the future.
I'm sure the criminals that will be brought to justice, and hanged, shot and stoned will understand the wisdom of this move.
In other words, what a simpleton.
Is he claiming he found a way to safely have backdoored communications?
Not sure what "safely backdoored" means. The system is spread out amongst many different countries in such a way that many different governments must agree to use the back door. If the USA, the Netherlands, and Russia can agree, for example, then it is probably criminal investigation and not spying going on. I reviewed many of the early drafts of this paper. It's pretty cool.
Or, another way to put it, a government needs to compromise only those 9 users to gain unlimited access to all encrypted communications through the system.
Is he claiming he found a way to safely have backdoored communications?
Nope. He is claiming he has implemented a method requiring multiple key servers to unanimously decide to work together to decrypt a message.
Specifically there are nine servers, all of which must be used together. If 8 of the 9 wish to decrypt something but 1 chooses not to assist, the message can not be decrypted.
He then suggests in his opinion that if those nine servers are spread around the world such that one is in control of by different democratic governments, it would follow that all nine of those governments must then agree the message in question needs to be decrypted.
So far as the axiom holds that "technology can do nothing except enforce a policy" - he is correct.
The question remains about those policies of course, not just at the time the nine servers are deployed and used but also for all time into the future.
Something he states no opinion on, which is also probably wise. My own cynicism has great doubts about that as well.
It's also worth pointing out that at least in the alpha stage of testing the protocol is currently in, this backdoor really is a "US backdoor", as for testing purposes all nine of those key servers are hosted within amazon cloud, so all under control of the same government.
During development testing this is fine, but the people testing the protocol should be absolutely aware of this fact. Test the other aspects of the protocol, assure the protocol as implemented matches exactly the theory. Find and fix bugs. But it is not to be used for trusted communications yet.
The next major hurdle of course is the very policies that need to be drafted and in place before the servers are codified to enforce them.
You know how governments and policies can be some times. It very well may be the case the policies never actually make it to a state anyone agrees is worth using, making the protocol a bit useless, even if not at the fault of the protocol itself.
It's DiceDot now. Corporate probably has focus groups of soccer moms saying the site assumes too much knowledge.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
What I'm taking away from this is that anything David ever has made or will make in the future should not be trusted.
With deep sorrow we announce the departure of another great security guy we once had. You will be missed.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Yes, I think it really is that simple. We (~99% of governments) already have laws and systems in place to get information needed for valid law enforcement purposes. No need for complex or technical systems of malicious spying under the deceptive guise of "tough on crime".
There's a term for that in data security circles. That's what we call NOT PRIVATE, for fuck's sake.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
In this case, a former /. member that hasn't bothered using their login for the last couple of years.
At least I don't know any algorithm that can prove the correct decryption key is embedded without actually decrypting the message.
On the technical side this does exist and is quite possible.
It is known as Secret Sharing
One example algorithm for this is called Shamir's Secret Sharing
Now I admit I didn't do more than speed-read the first bit of the linked paper for this protocol, but at first glance it looks to utilize three separate "encryption wrapper" stages, where having a known static key embedded would only defeat one of those three.
I can't say if that is enough to do as you claim however maybe you're right.
So you go through nine jurisdictions, get a court warrant in each and find the decryption key is 0xDEADBEEF. Then what?
On the political side, I can't answer your question because I am of the belief this can't possibly work politically. There's no real need to break something that was broken from the start after all.
1. Get a copy of the PrivaTegrity,
2. De-compile it
3. Analise product
4. Remove Back Door.
4.1 Put a new back door in it?(this part never gets old)
5. Miller Time.
So... my question would be... Quis custodiet ipsos custodes? who will appoint, monitor and document the decisions of these administrators and if necessary revoke their anointed status as the determiners of what is or isn't acceptable evil (e.g. is sharing a commercial movie evil enough to attract the attention of "the nine"... how about a casual statement calling for the non-constitutional overthrow of a government... clearly child porn would be considered evil, but what would the cut off age be, 16, 17 or 18... would planning to blow up a public facility in a western country be more evil than threatening to blow up a public facility in a country already mired in a civil war)? Will they be accuser, prosecutor, judge and jury? who will take cases to them and which legal system will apply... can they be sued in the event that they err? what will keep them beyond reproach and will their decisions be made public? will it be possible to appeal their decisions?
Lots of questions and no clear answers.
Come on Slashdot. Get your shit together. One would think that you could find a way to implement new account creation by now!
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
... and > 9 "democratic countries" fell for the falsified "weapons of mass destruction evidence" the US presented to lure them into supporting the Iraq war.