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Distributed Security
A reader writes: ""Where Schneier had sought one overarching technical fix, hard experience had taught him the quest was illusory." A long and detailed article at The Atlantic Online on why Bruce Schneier has come down from his strong cryptography tower to preach the gospel of small scale, ductile security against the popular approach of broad scale, often high tech security that often proves to be very brittle."
so 'distributed' is the new buzzword, huh?
I think I'm going to create a distrubited ASP, umm.. internet synergy proxy. it'll use a beowolf cluster of nodes of umm, privacy and corporate responsiblity.
so.. like.. send me your money, and I'll set it all up there..
Haven't we been here before, about a year ago?!
Ductility - the ability to fail gracefully - isn't just essential in the area of security, it's true for reliable systems generally. All programmers who've worked on stuff like Combat Systems for ships, aircraft avionics, railway control systems etc should know this, and most do.
There are 2 ways of making things secure - either against outside attack, or internal failure. I call them the Battleship and the Blob. With the Battleship, you load up the Firewall, or put in 2048-bit encryption, or even have an air gap. You basically rely on a layer of "armour plate" that your predicted threat can't penetrate. But this often fails - the threat either goes around the armour, or the incoming shell is bigger than you'd bargained for, and penetrates. Far safer in practice, though not in theory, is the Blob. This has layer after layer of safety features, each of which is easily circumvented in isolation, but every one of which limits the damage. Bugs can exist, attacks get through, but it works anyway. You can shoot the Blob full of holes, but it keeps on oozing along... Terminator 2 not Terminator 1.
What does this mean for programmers? Use strong typing (if your language doesn't support it, fake it with explicit sanity checks, boolean isSane()), always check inputs for sanity, check your outputs are plausible at least, get good peer review on everything, KISS, basically all the techniques professional Software Engineers rather then 31337 haXOrs have been spouting on about for some time. The software equivalent of "Wear belt, braces, keep a piece of string in your pocket, and then make sure your underwear's in good shape."
Zoe Brain - Rocket Scientist
Technological solutions for social problems (like legislative ones) are only as good as their worst failure mode.
I'm tempted to write more in this /. comment but I think that idea is pretty deep. The article (for those who didn't want to read it all, I don't blame you) describes how Schneier came to realize this.
I believe one of our ex-presidents (LBJ perhaps) has a quote where he expresses the same idea about laws.
Unfortunately, the most effective solutions aren't always the ones chosen. Our current government seems to have no concept of the idea that you don't just have to "do something", you have to do the right "something".
Since /. readers are such a cynical and paranoid bunch, we can come up with all sorts of failure modes for today's "security". Imagine the dumb blank look that would appear on Ashcroft's face if you asked him "what if someone gets a copy of the fingerprint used in those biometric systems? will the federal government be paying for finger transplants?". Then after a few seconds the blank look will disappear, and the lies and bullshit would stream out.
Just like the TV talk shows. One intelligent guest will make a simple point ("what if they sharpen the edge of a credit card? isn't that more dangerous than a nail clipper?"), which to me would be an instant show-stopper, forcing me to stop and re-think the whole system, but then the other guests will pile the bullshit so high the point is quickly forgotten.
It makes you wonder if the legislators actually consulted any security experts (that weren't trying to sell something). Probably not.
The article brought up a good point about cryptosystems that depend on keeping the algorithm secret. Once that secret gets out, the security is hopelessly compromised. The Germans learned this the hard way in WWII.
I think this has a nice parallel to the entertainment industry's approach to DRM. The fiasco with DVD encryption is a perfect example. Once the format was broken, the genie was out of the bottle. Making laws to try and stuff the genie back in just will not work.
With the ever increasing number of people who try to break security protocols as a hobby, it seems that relying on secrecy to keep things safe is a recipe for disaster. The internet allows information to be distributed so quickly and widely that no secret will stay secret very long.
If the entertainment/software/etc industries continue to rely on their nonexistant ability to keep secrets, we will either have an overabundance of silly overbroad laws, or else the companies will falter and die. No matter how large and dedcated their tech geeks are, there is no way to match the vast number of hobbyist nerds trying to break stuff for fun.
Very long, but worth the time to read. I've been a big fan of Schneier since i read his book a few years ago.
Best Article quote: "Cryptophiles, Schneier among them, had been so enraptured by the possibilities of uncrackable ciphers that they forgot they were living in a world in which people can't program VCRs.
Perfect timing as I'm gearing up for CRYPTO 2002 at UCSB, YAY!
-Nick
<clip> "The trick is to remember that technology can't save you," Schneier says. "We know this in our own lives. We realize that there's no magic anti-burglary dust we can sprinkle on our cars to prevent them from being stolen. We know that car alarms don't offer much protection. The Club at best makes burglars steal the car next to you. For real safety we park on nice streets where people notice if somebody smashes the window. Or we park in garages, where somebody watches the car. In both cases people are the essential security element. You always build the system around people."</clip>
Luke: You were in the Crypto Wars?
Schneier: I was once an RSA Knight like your father. He was the best Composite Factorer in the whole galaxy... I see you have written programs that factor large numbers yourself. He was a good friend. Before the Dark Times, before The Empire.
Luke:What happened to my father?
Schneier:A young RSA Knight by the name of Len Adleman betrayed and murdered your father. Adleman was seduced by the Dark Side of the Force
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
Prove to me that America was intentionally trying to kill innocent civilians, and I'll listen to you.
Yes, but the point is one of the reasons that there is a lot of ill feeling towards the USA is because of its double standards. Let's be frank about this - the fact of the matter is that the American people do value American lives more than those of other people. There's no "seems to" or "gives the impression of" about it. If a few American military men die in action then it's front page news and they are "American heroes". A few hundred Afghans die and its like "Oh dear. Oops. Well, these things happen. Whatever."
I haven't heard that story before. Can somebody point me to a source with more details?
As a hacker of your system, I'm all for this. Now I don't have to break your password, just spoof the USB packets.
Thank you much.
J. Hacker Anonymous
Take a look at Ross Anderson's home page, read a few of his classics like "Why Cryptosystems Fail", "Programming Satan's Computer" and "The Cocain Auction Protocol".
Ross' book "Security Engineering - A Guide to Building Dependable Distributed Systems" should be mandatory reading for anyone who writes code for networked computers - no matter what kind of computers.
I feel that one of the biggest threats to Internet security today is the inability to learn from history. That is, after all, at the core of the engineering arts and sciences.
I would like to sugest a new kind of biometric identification - the Personalized Advanced Identification Norm ( P.A.I.N. ).
The user is made to read Slashdot articles at level -1 for 15 minutes. During that time the pattern in which the user bangs his/her head in the table is measured. This pattern is trained into a neural-network, that is later used to identify the user.
This method is a bit slow but i'll personally garantee that it's fail-proof (trust me).
Nice to see one who is so respected to be humble enough to say 'I was wrong'.
Of course this is old news as his book "Secret & Lies" discusses all this in detail.
What Schneier actually advocates in the article is the use of at least two of these three layers for doing user authentication: something you know (e.g. a password), something you have (e.g. a smart card or other secure token), and something you are (biometrics falls into this rubric). Depending on only one is necessarily weak, but even two of the three taken together would be strong indeed. For instance, if you have a website that uses not only username/password pairs for authentication, but lives on SSL *and* requests client-side certificates from any browser that wishes to visit the protected page uses both something you know (your username and password) and something you have (the computer where the browser with the client-side certificate is installed, or better yet if the cert lives on a smart card). THAT would make Schneier's Parable of the Dirty Website fail utterly without extra work: without the client-side cert, the web page wouldn't even serve the username/password page to you. Fine, the password is compromised because the employee used the same password to surf for porn, but since access to the certificate is limited to the computer where it's installed, or the smart card possessed by the employee no dice unless you can also steal the smart card and/or computer. Even better would be to provide biometric authentication for the secured computer, so you'd then have to steal the fingerprint or retinal scan or whatnot as well to break the system.
It can be done of course, but it would require contortions worthy of Sneakers .
The whole article actually feels like a distillation of the last six months of the Crypto-Gram newsletter.
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
Like Schneier says, a good sentry is one of the best additions to the security blanket. Trouble is, where do you find good sentries? Night watchmen are some of the worst paid employees on the payroll, and time and time again have been shown to miss the obvious attacks. It's repetitive, boring work that most people would hate.
The problem lies with the way the human brain operates. We evolved to match patterns as a survival skill. To pick out images from masses of almost random data. Is that a piece of ripe fruit on that tree over there? We are so good at it that we can see patterns in anything: faces in inkblots, or subtle "head and shoulders" movements in stock markets. Generating false positives is also a survival trait when it comes to looking for threats. Is that moving mass of lines the face of a tiger, or a snake? Better to be cautious and check it out.
But monitoring for exceptions is not a thing that humans are good at. Staring at production lines filled with identical chocolates looking for the one that isn't right, human eyes and brains fail at this task. What happens is that your pattern matching circuitry spots the wrong pattern: "these are all the same so there is no problem" each new piece of incoming data confirms this and the brain goes to sleep (try it some time!).
At airport scanners the operators have to take very frequent breaks from studying the X-ray images of suitcases. On top of this, every 10 minutes or so, a bag is fed through that they should react to. Like they say, this keeps them on their toes, or put differently stops pattern matching saying "I already found the pattern, stop bothering me with new data". This approach is better but it is still too labour intensive.
IMHO the way forward lies in a combination of human and automatic scrutiny. The automatic part consists of filtering out the routine, leaving human eyes to sort out the final details. If a security system generates 1,000 alerts an hour it will be ignored. Making a more sophisticated system that cuts down the number of false alerts is usually expensive and as Schneier suggests more likely to weaken things by giving a false sense of security. If however, the system generates 1,000 alerts and flags up the 10 most suspicious for human eyes to look at in detail then you capture the best of both worlds. The smart piece is the algorithm that ranks the alerts as more or less interesting and this is where security experts make the difference.
What Schneier is suggesting is that human+machine monitoring of a smaller range of very specific inputs is better than automatic trawling of masses of nonspecific input.
Good article, well worth the read.
Bad technology that takes away human initiative is used in the US because the good people are too expensive and the cheap people are not reliable. Besides there is a perpetual labor surplus especially of the people who will work for cheap due to basically unrestricted immigration. And since so many of the immigrants come from non-Western European countries there will never be mass public support for paying them higher wages. Those are the facts that limit the effectiveness of security in the US, or the effectiveness of many other things.
There is an incredible article in this month's The Weekly Standard Patio Man and the Sprawl People. David Brooks' insight into the American psyche is that the American approach to problems is to move away, especially to move away from people who are different, to move to a community of similar people. Where people stay rooted such as the South there is open conflict. Where people move to new communities such as the suburbs there can be a facade of acceptance--until too many of the different people start to move in.
In recent years I have noticed an increasing chorus in the media extolling the virtues of Europe, its peacefulness, its openness. I feel a small nagging doubt similar to when I heard praise for Japan's system in the early 80s. In the case of Japan the Sony headed by Akira Morita is not the Sony of today, and in the case of Europe, it does not seem to be headed in the direction of the one long-lasting democracy on that continent--Switzerland. The vaunted EU hardly submits every question of importance such as the Euro to referendum, unlike Switzerland. And even more worrisome, the direction of Europe the past century has been continuous fissioning of countries, instead of Switzerland's keeping itself together despite populations native speaking at least four different languages. Europe essentially murdered or expelled much of its Jewish population, it has not solved the Roma problem, and now Europe is struggling with Muslim immigration.
Even when European countries stay intact all is not well. Is not Italy's problem between north and south the same as the United States'?
Almost all conflict in the past couple of centuries can be summarized as the painful transition from agricultural serfdom to industrial society. A successful modern nation needs to actually pull off two incredible reformations, while most can't manage one. First agricultural serfdom has to be reformed so that small farmers own their land. Switzerland accomplished land reform in the 1800s, Japan had land reform imposed on it by General Douglas MacArthur during the Occupation because it was the only way to prevent a Communist insurrection. Once the land is put in the hands of a land-owning small farmer class there will be no danger of revolution. Sadly nations such as Russia have not accomplished just this one step over the past two centuries. Second, and perhaps paradoxically, the populace must in large part move to the cities and the power of the rural areas over the government must be diminished, for the rural areas tend to be more conservative and less willing to support reform.
Needless to say the vast majority of the nations on this planet have not successfully reformed themselves, twice. Thus there is an endless supply of refugees and endless labor surplus. Security remains far off and elusive.
The problem with Biometrics is that in the end it is nothing more than a digital signal going down a wire. If the hardware can be compromised, then your physical attribute that can be measured just becomes another signal that can be captured and replayed.
It's not the intent that bothers me so much as the method. Our military has difficulty discriminating actual threats from innocent behavior. When we place it into a situation where there are many apparent threats, it shouldn't be surprising to see fatal mistakes.
Look at some of the major incidents in Afghanistan: if our military sees/hears gunfire, it often assumes that it's under attack, and retailates - even if it's a wedding party or an ally under military maneuvers. It's the same thing that Bruce is talking about - a single failure in threat discrimination can lead to deadly consequences for civilians, and increased hostility against America. Even though there is no direct intent to injure civilians or allies, the training and structure of the system encourages poor reactions and often results in undesired and unnecessary casualties.
Yes, the terrorists are responsible for their intent to harm civilians. But we are also responsible for developing a system that tends to harm civilians in its failure modes. Time to develop a ductile military system, perchance?
AC is right. In a democracy we are all responsible for the actions of our government, however distasteful they are and whether or not we voted for them. It is unlikely that Bush would have seen to have been resonsiple for upsetting the terrorists that precipitated September 11th, it is more likely a number of actions (or inactions) by different governments over time. If we want our governments to be seen to be less offensive then there is always the ballot box. After the fall of the Soviet Union, we all let countries like Afghanistan suffer, and after arming them to the teeth as well.
Organisations such as USAID do a fine job, but there good works are undermined by stupid politicians who couldn't find central asia on a map until they had seen it on CNN.
Which is not to say that a biometric device combined with intelligent human oversight (so you'll be spotted if you try to use an artificial hand to fool a device based on hand and finger sizes, for example) isn't an appropriate component of an authentication system, and the article gives an example in use on Mr Schneier's home turf.
Seriously, do read the article, even if it is a little on the long side. It contains a lot of good sense: in particular its emphasis on putting human decision-making back into the loop, rather than looking for all-encompassing technical solutions. We're clearly not yet at the point where our technology is sufficiently advanced that it can act as if by magic - as a lot of snake-oil merchants pretend, and a lot of quick-fix politicos who should know better affect to believe.
Shneier et al just released a paper about a PGP/GPG vulnerability. This vulnerabilty relies on the PGP user not being paranoid, and doing something that's not too smart.
So, once again, you're only as secure as the weakest link, which is often the user...
/Styx
So, security benefits from a strategy in which it fails gracefully, and is best implemented in small, easily manageable pieces?
And security also benefits from a reliance upon complex (human) intelligence instead of simplistic boolean concepts of success/fail?
Hmmm, doesn't that sound like just about every other kind of system in the world? Whether we're talking about how to build elegant systems that fail gracefully, or how to build systems that deliver what you want rather than what is easy, there are examples all around us.
However, if we look farther ahead and we will see another set of problems. For example, a reliance upon humans to evaluate system performance (whether the system is a security system or a telephone network) is expensive and is also unreliable. One of the next steps is SPC - where we can provide tools to help the humans automate much of the drudgery of looking through gazillions of bytes of low-level information.
In recent years I have noticed an increasing chorus in the media extolling the virtues of Europe, its peacefulness, its openness. I feel a small nagging doubt
One of the key differentiators between the US and the EU is that the US has a far lower population density. And because of the conquest and genocide of the indigeneous population, much of the land in the US was wide open and available for colonisation. As your referenced article points out, this led to the emergence of an "avoidance" strategy for handling social development in the US: just up stakes and move west, young man.
For the most part, Europeans don't have this luxury. The social networks that bind European societies are more complex and tightly knitted than US ones. It's related to how the sociologist Norbert Elias describes social interdependencies and the mannered society. European manners have evolved to handle large groups of sometimes wildly divergent peoples and cultures that must live intermingled with each other.
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