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Comment Re:stupid (Score 3, Interesting) 558

The NSA and its friends already track who logs into your website (or at least the IPs that do) so I wouldn't worry about that one too much.

One technical measure that has been floated recently is the idea of using Bitcoin. What you do is provably sacrifice some bitcoins to miner fees, thus creating a kind of anonymous passport. That proof of sacrifice has public keys embedded in it to which you own the private keys, and it was provably expensive to create. So the idea is that you sign up with your passport and then if you misbehave, it can get added to a blacklist kind of like how Spamhaus blacklists IP addresses. Now you can set the cost of abuse to a precise degree. Good users only have to pay once and can use the same passport for years. Abusers find their business models are unprofitable.

Unfortunately the software and protocols for that aren't implemented yet.

Comment Re:Deciphering != Reverse Engineering (Score 1) 245

If you're talking about things like protecting copyrighted games then no, it's not particularly relevant, because you're typically trying to bind to some physical medium like a CD and obfuscation can only hide what you're doing to a certain extent.

However it's very interesting as a building block for other schemes. Functional encryption in particular will be very powerful, but probably not until 10 years from now. It's really an entirely new paradigm, as revolutionary as the invention of public key crypto itself (which also started out unusably slow).

Comment Re:Deciphering != Reverse Engineering (Score 3, Informative) 245

Yes, it is robust. I read the paper a few days ago.

All these comments about how you can "just look at the CPU instructions" are made by people who haven't been following developments in the field. The program never gets decrypted into CPU instructions. Heck, it was never even compiled into CPU instructions in the first place. It gets compiled into a form of boolean circuit, a mathematical equivalent of an electronic circuit that is composed of AND, NOT, OR, XOR gates and wires between them. Then that circuit is itself again transformed into a series of matrices and at that point I hit the limit of what I could understand without needing to read some of the cited papers.

This is a very, very complicated technique that builds upon decades of cryptographic research. If they say it's secure in the cryptographic sense, I think it's very likely to be so.

Comment Re:I Call BS (Score 1) 245

And this is a Computer Scientist? Are they sure they haven't accidentally hired the actor who played Charles Epps in "Numb3rs"?

At some point this program will have to be executed by the CPU, but somehow even a disassembler would throw up its hands and declare defeat when presented with this "encrypted" code. In other news, Mr Sahai's found a way to turn your grocery list into a set of numbers that will make it impossible for anyone else to see what you want to buy. All they can do is turn it over to the clerk and watch in awe as he fills your bags.

I can assure you that Amit Sahai is not only a computer scientist but a highly respected cryptographer. The reason the explanation is so garbled is he tried to dumb down cutting edge mathematics for the purpose of a press release.

The code is encrypted in such a form that it is never decrypted into CPU instructions. Every operation the program does is a form of mathematical transformation. Yes, it's got a lot of overhead (probably impractical at the moment). The grocery analogy is a lot closer than you might imagine.

Comment Re:The original paper (Score 1) 245

I already read the paper some days ago when it was first uploaded to the IACR pre-print archives. Yes, the paper is the one being referred to. It's a very interesting result, although not really impactful at the moment for things like game DRM.

The confusion arises from terminology. The technique applies (presently) to pure functions. You can write those functions in, for example, a subset of C because there exist compilers that transform such programs into boolean circuits, and circuit form is what they obfuscate. However it's rather rare to find examples of useful programs that are actually pure functions (compilers themselves being the most obvious one). Most programs have state, rather complex state at that.

Now there was also recently a paper that showed a way to build garbled circuits that had read/write access to a form of memory. If the two techniques can be combined then you're starting to see progress towards "real" obfuscation as used in industry.

Comment Re:Can any government really stop BitCoin? (Score 3, Informative) 185

That's a nice theory. In practice what happens is one special interest or another does their own research that tries to demonstrate that something is harmful. Then they go lobby politicians who go "ooh err a study shows $X is harmful, maybe should ban it". Then the other side lobbies to try and undermine that study or convince the politicians not to go ahead. You can call this process the government proving something if you like, but that's not really correct.

To demonstrate this point, please find me a serious, government-sponsored cost/benefit analysis of anti-money laundering laws. I've yet to find one. Wikipedia's take. There are various attempts by academics and accountancy firms, but they are all hobbled by the fact that nobody can even measure how much money laundering takes place (heck even defining what it actually is, can prove troublesome).

Here's a statistic for you to chew on. The concept of money laundering was first invented by the USA in 1970, so about 40 years ago. It has been constantly ratched up since then. Yet in the last 20 years the street price of cocaine has more than halved (page 81, adjusted for inflation and changes in purity). In other words, despite the massive effort put into the war on drugs and all the effort put into AML, it hasn't been enough to even balance increased efficiency of the drug cartels. We can perhaps consider that the price would be even lower if it were not for AML. But that hardly seems to matter against a backdrop of such utter failure.

Comment Re:stupidity won again (Score 1) 168

The court assumes that bad guys don't already have this knowledge. From decades of experience in IT security we can conclude with near certainty that they do.

Erm, no you can't. Your experience is obviously wrong if you conclude that.

Immobilisers are mandatory in the EU since 1998 because they had an absolutely massive effect on car theft. From el wiki:

Statistics in Australia show that 3 out of 4 vehicle thefts are older cars stolen for joyriding, transport or to commit another crime. Immobilisers are fitted to around 45% of all cars in Australia, but account for only 7% of those cars that are stolen. In many instances where a vehicle fitted with an immobiliser has been stolen, the thief had access to the original key. Only around 1 in 4 stolen vehicles are stolen by professional thieves. The majority of vehicles are stolen by opportunistic thieves relying on finding older vehicles that have ineffective security or none at all.

From this paper

Application of the security device reduced the rate of car theft by an estimated 70 percent in the Netherlands and 80 percent in England and Wales, within ten years
after the regulation went into eect. Based on micro-data on time to recovery of stolen cars for the Netherlands, we nd that the device had a greater impact on theft
for joyriding and temporary transportation than on theft for resale and car parts. The costs per prevented theft equal some 250 Euro for England and Wales and 1,000 Euro for the Netherlands; a fraction of the social benets of a prevented car theft

Obviously, in that timeframe not all immobilisers were secure, as we're now learning that some have exploits (also see the BMW recall). Yet car theft dropped a lot anyway. The only explanation is that "bad guys" (who come in all shapes and sizes) did not have that knowledge, the skills needed to be a car thief not often overlapping with the skills needed to break complex security electronics.

Comment Re:Punishment out of proportions? (Score 4, Interesting) 84

Yeah, that's what I thought on reading the summary too. 30 years for wire fraud?

I read an interesting article in the Economist the other week. It suggested that countries where children are spanked tend to have populations that support harsher prison sentences.

People who as children experienced the “powerlessness” of frequent spankings report a disproportionately greater interest later in life to own guns, Mr Pfeiffer says. They also demand more draconian prison sentences, including the death penalty, for convicted criminals. And they seem more prone to violence themselves. In a study of 45,000 ninth-graders Mr Pfeiffer conducted in 2007-08, those kids who had been beaten by their parents were five times as likely to commit repeated crimes or to use cannabis, and missed school four times more frequently for ten days a year or more.

Scandinavian countries, in part inspired by the children’s books of Astrid Lindgren, the author of the popular Pippi Longstocking (pictured) series, were the first to make spanking illegal for teachers in the 1950s and 60s. Between 1979 und 1983, they also outlawed spanking by parents. Crime rates, gun ownership and prison populations have been falling since.

By contrast, spanking is still common in large parts of America, especially in the Evangelical milieus of Southern states. This is also where crime remains relatively high, gun ownership common, and incarceration excessive. (America’s incarceration rate is between eight to ten times that of northern European countries.)

Correlation does not imply causation and all that, but it's still an interesting theory as to why the US is so far out of step with the rest of the world on crime and punishment.

Comment Re:Self signed certs (Score 3, Informative) 148

Common misconception - certificate authorities do not have private keys. Your private key never leaves your own computers. That's why the NSA would have to force companies to cough them up (or steal them).

Also, for normal SSL having the private key lets you passively eavesdrop and decrypt. For souped up SSL with forward secrecy it doesn't, it only lets you MITM the connections, which results in the server and client having a different view of things - that's detectable, whereas a leaked SSL key isn't.

Forward secret SSL is new, and not that easy to do. At the end of 2011 Google employees did the necessary upgrades to OpenSSL, but most other sites haven't deployed it (yet). Enabling forward secret SSL is the best and easiest step forward to beat the NSA/GCHQ right now, because if they HAVE obtained your private key, it forces them to start actively intercepting connections which is expensive and detectable.

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