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Comment Re:One time pad (Score 1) 118

What you've described has been known for centuries as a "book cipher". Benedict Arnold used one during the American Revolutionary War to protect his treasonous communication with England.

Anyway, there's a really fun way to beat this kind of encryption today. If Mallory can get Alice or Bob to send a copy of BLACK_SQUARE.BMP, it's literally game over. Imagine XORing your key against a bunch of binary zeros. The result is a big patch of the cleartext version of the data that is your key. Google will find that faster than you can.

I did this to a friend who had the same idea in a "you'll never guess my encryption" challenge. After getting him to download a copy of BLACK.GIF, I stared at the intercepted results for many seconds longer than I should have. It output a repeating string of something like SLASHDOTTODHSALS, so I said that's your key. He was arguing because his key was SLASHDOT, and his "algorithm" was to invert the letters of the key word and append a copy to the end of the key. My mind boggled because I was expecting encryption, not immediate success at recovering his key and data.

Now, let's say you're smart enough to avoid encrypting BLACK_SQUARE.BMP. I can still achieve most of the same results by predicting that your data stream will contain "Host:", "Content-Type:", "Accept: text/plain", "User-Agent:", "HTML", "BODY", and other such 'cribs' (I was all set up to apply this logic to the intercepted message from my friend mentioned above.) By matching fragments of my guesses with your message, I can look to see if I recover legible text. It only takes a surprisingly small amount of recovered text to be able to identify the source.

Comment Re:Different approach (Score 1) 76

There is this piece of Cat 5 that isn't remotely hackable. Unless it's tapped, or if someone puts an inductor on it, or if they use TDR to estimate the length of the wire to figure out the distance between routers and discover where the Intrusion and Detection Systems are located.

Comment Re: Silly but (Score 1) 471

Dress codes make a slight amount of sense when the company has a requirement that many employees must wear uniforms. It's not fair to say, "you people who stand in front of customers all day must wear a blue shirt, green tie, and khaki pants" but then say, "you people are in the main office, so you're exempt from dressing like a dork." Some of the line workers resent it. Management can then decide if they want to settle the matter by subjecting everyone to a dress code.

Of course HP doesn't require line workers to wear uniforms, so that's not the case here. This is just another stupid and capricious management decision by a company that's become famous over the last decade for having the most incompetent management of any (formerly) major corporation. HP's executives have been so bad it's easy to imagine an evil Michael Dell offered HP's board of directors one hundred million dollars -each- to sabotage HP into oblivion. (Hey, it makes a lot more sense than any other reason for imposing a dress code on engineers.)

Comment Re:Approach security the wrong way? No shit! (Score 1) 157

Good point. First, IANAAEE (I am not an automotive electrical engineer) so much of this is speculation, but not all of it. I do think small, hardware firewalls ("data diodes") could help prevent a lot of these problems. I also agree with you in that I don't think the direct access is necessary, but I think it might loop around in such a way that the holes end up being present anyway.

Consider: the crash message from the airbag sensors, which is on the high speed engine control bus (ECB) goes to the door locks. The door locks are on the low speed bus (security network), but bridge both networks. A data diode could stop messages from the door locks from flowing back to the high speed ECB. The door locks, ignition key, and immobilizer are all on the security network. The ignition key talks to the immobilizer. Finally, the immobilizer talks to the ECU, which is on the high speed ECB.

The security network is supposed to be isolated from the cabin comfort network (where the infotainment system, navigation system, and cell phone stuff are.) But the crash signal has to travel to the cell modem somehow, so another component has to allow messages from the ECB to the cabin bus. Plus, some of these cars have "remote start via cell phone", so something still has to enable messages from the cell modem to travel to the immobilizer. How do they get to the security network? (Bigger question: do the Chryslers even have a security network, or do all low speed messages share a common bus?)

If everything were perfect, the immobilizer would be the only potential spot for the bridge; and because the immobilizer's entire job is to prevent the engine from starting unless all the security is perfectly aligned, it seems like the natural place where the engineers would focus their security attention to isolate the low speed bus from the ECB. But obviously not everything's perfect.

It seems like they should have a set of dedicated data protection devices that would be similar in concept to a traffic signal's conflict monitor, somehow hard-wired with a rule that allows only whitelisted messages from the modem to go to the immobilizer.

Comment Re:Where's the hardwired switch? (Score 1) 157

Want a more adventuresome automotive experience? Go to India. During the three weeks I was there, our driver's car was struck more times by more vehicles and pedestrians than I've seen in my 35 years of driving in the US.

The drivers are worse than you can imagine. "Keep left" is more of a guideline than an actually obeyed rule; "keep center" seems to be the observed behavior. The few traffic police I saw were standing in small gazebo-like boxes in intersections - they were not driving interceptors or squad cars. Peddlers and beggars wander among cars slowed down on the roads, selling umbrellas and toys, and asking for handouts. Fuel tankers have signs lettered across the back: "KEEP BACK 25 FEET", but nobody pays attention. Lane markers are apparently nothing more than wasted white paint decorating the road. On the road in front of you you may encounter a farmer with a pony cart, bicycles, pedestrians, elephants carrying loads, and yes, the occasional unattended cow.

And the honking! Seriously, India, WTF is up with the continual honking? You can drive a full week in many cities in the USA without hearing a single car horn.

We saw all this on every single trip, including a 2AM drive from the airport.

An inattentive driver would cause an accident within a split second; this may be why minor accidents and collisions are so common.

Comment Re:Approach security the wrong way? No shit! (Score 1) 157

Consider the safety network, which has data from the crash sensors, rollover sensors, seatbelt sensors, and seat occupancy sensors, and mixes all of that data together in a set of rules that instantly trigger the correct airbags and seatbelt pre-tensioners. It also needs to connect to the infotainment system to take over the car's data or phone connection to send a message to emergency services. In turn it may also get data from the navigation system to report location information. It may trigger an unlock of the car doors to assist bystanders in rescuing the occupants, and it may shut off the engine to prevent further injury. It may talk to the signalling systems to turn on the 4-way flashers to help first responders find the car. The car door lock system is part of the security bus, which talks to the engine immobilizer, responsible for talking to the ECU to start and run the car. All of those data feeds that seem like they could be isolated have real operational needs to come together in multiple devices.

The rules in a car are exponentially more complex than ever before, and they're increasingly vital for safety; not just comfort or entertainment. Consider how many lives have been saved because their airbags deployed, and the emergency responders were able to dispatch an ambulance in time to save a crash victim from dying. Now consider how many people have died from crashes directly induced by CANBUS hacking.

The safety systems of today are doing their jobs better than ever, which is the topmost goal of the engineers. Also consider the safety systems need to guarantee reliable operation to work for the first time ever in an actual crash. If they can layer on system security without compromising occupant safety, they will, but not at the expense of crash survivability.

Comment Re:Morse Code (Score 1) 619

Oh, wait, you didn't need to pass a test for that.

I'm just trying to think how that would have been possible. I think back then there was a medical exception you could plead for. I didn't. I passed the 20 WPM test fair and square and got K6BP as a vanity call, long before there was any way to get that call without passing a 20 WPM test.

Unfortunately, ARRL did fight to keep those code speeds in place, and to keep code requirements, for the last several decades that I know of and probably continuously since 1936. Of course there was all of the regulation around incentive licensing, where code speeds were given a primary role. Just a few years ago, they sent Rod Stafford to the final IARU meeting on the code issue with one mission: preventing an international vote for removal of S25.5 . They lost.

I am not blaming this on ARRL staff and officers. Many of them have privately told me of their support, including some directors and their First VP, now SK. It's the membership that has been the problem.

I am having a lot of trouble believing the government agency and NGO thing, as well. I talked with some corporate emergency managers as part of my opposition to the encryption proceeding (we won that too, by the way, and I dragged an unwilling ARRL, who had said they would not comment, into the fight). Big hospitals, etc.

What I got from the corporate folks was that their management was resistant to using Radio Amateurs regardless of what the law was. Not that they were chomping at the bit waiting to be able to carry HIPAA-protected emergency information via encrypted Amateur radio. Indeed, if you read the encryption proceeding, public agencies and corporations hardly commented at all. That point was made very clearly in FCC's statement - the agencies that were theorized by Amateurs to want encryption didn't show any interest in the proceeding.

So, I am having trouble believing that the federal agency and NGO thing is real because of that.

Comment Re:Morse Code (Score 1) 619

The Technican Element 3 test wasn't more difficult than the Novice Element 1 and 2 together, so Technican became the lowest license class when they stopped having to take Element 1.

The change to 13 WPM was in 1936, and was specifically to reduce the number of Amateur applicants. It was 10 WPM before that. ARRL asked for 12.5 WPM in their filing, FCC rounded the number because they felt it would be difficult to set 12.5 on the Instructograph and other equipment available for code practice at the time.

It was meant to keep otherwise-worthy hams out of the hobby. And then we let that requirement keep going for 60 years.

The Indianapolis cop episode was back in 2009. It wasn't the first time we've had intruders, and won't be the last, and if you have to reach back that long for an example, the situation can't be that bad. It had nothing to do with code rules or NGOs getting their operators licenses.

A satphone is less expensive than a trained HF operator. Iridium costs $30 per month and $0.89 per minute to call another Iridium phone. That's the over-the-counter rate. Government agencies get a better rate than that. And the phone costs $1100, again that's retail not the government rate, less than an HF rig with antenna and tower will cost any public agency to install.

You think it's a big deal to lobby against paid operators because there will be objections? How difficult do you think it was to reform the code regulations? Don't you think there were lots of opposing comments?

And you don't care about young people getting into Amateur Radio. That's non-survival thinking.

Fortunately, when the real hams go to get something done, folks like you aren't hard to fight, because you don't really do much other than whine and send in the occassional FCC comment. Do you know I even spoke in Iceland when I was lobbying against the code rules? Their IARU vote had the same power as that of the U.S., and half of the hams in the country came to see me. That's how you make real change.

Comment Re:It is the oppressive governments that are uneth (Score 2) 70

So how is Hacking Team different than a company that sells grenades to Syria? Are all companies that make grenades unethical, because there is no non-violent application for hand grenades? What if they're used for defense purposes?

What about a dual-use item, such as selling cattle prods? Are all companies that make cattle prods unethical? If cattle prods are used for an off-label application (torture of humans), is it ethical to sell them to someone you suspect might be using them for torture, even if they don't explicitly say "we want to buy 10 cattle prods for our Glorious Leader's Torture Squad"?

Conversely, Hacking Team might be selling the 0days to legitimate law enforcement agencies, who may be using them to prevent kidnappings and murders. Is that ethical or unethical? Can you absolutely tell based on the customer's return address being London vs. Pyongyang?

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