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Is Your GPS Naive?

CmdrTaco posted more than 7 years ago | from the what's-a-dikfor-anyway dept.

Hardware Hacking 291

mi writes "Many GPS devices today will try to scan the FM bands for traffic advisories in the area to display on their screens. The signals, however, are neither authenticated nor encrypted, and one can — with commonly available electronics — construct a device to broadcast bogus advisories. Possible codes range from "bullfight ahead" to "terrorist attack"..."

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291 comments

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An even better application: (5, Insightful)

Ph33r th3 g(O)at (592622) | more than 7 years ago | (#18832863)

"Speed trap ahead."

An even better application: (-1, Redundant)

Cockmongler (1091711) | more than 7 years ago | (#18832909)

"Speed trap ahead."

An even better application: (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#18833719)

"Speed trap ahead."

An even better application: (-1, Redundant)

kakofb (725561) | more than 7 years ago | (#18834411)

"Speed trap ahead"

Re:An even better application: (0, Offtopic)

phantomcircuit (938963) | more than 7 years ago | (#18832911)

I feel a bull fight coming on....

Social hack - use "bullfight" for "speed trap". (5, Funny)

khasim (1285) | more than 7 years ago | (#18832981)

If there isn't one specifically for "speed trap", then re-purpose one of the lesser used code. I'd recommend "bullfight" just because there will be very few instances of its legitimate usage.

Re:Social hack - use "bullfight" for "speed trap". (1, Funny)

Anonymous Coward | more than 7 years ago | (#18833171)

I'd recommend "bullfight" just because there will be very few instances of its legitimate usage.

But then what do we use to notify others of cock-blockers?

Re:Social hack - use "bullfight" for "speed trap". (1)

garcia (6573) | more than 7 years ago | (#18833543)

I'm really waiting for the day that GPRS (or the like) is used to transmit the positions of those assholes hiding in the medians. Fair is fair. If they're allowed to hide (in OH they seem to have to be in fairly plain sight and have their parking lights on) we should be allowed to do basically the same thing.

Unfortunately, because local municipalities entire judicial systems are paid from a good percentage of the fees gained from these fines, there is no impartiality and that would be illegal.

Re:Social hack - use "bullfight" for "speed trap". (5, Insightful)

portforward (313061) | more than 7 years ago | (#18833661)

Or alternatively, you could just drive the speed limit.

Re:Social hack - use "bullfight" for "speed trap". (1, Insightful)

icebrain (944107) | more than 7 years ago | (#18834237)

Or, they could make the speed limit reasonable, instead of setting it to nonsensically-low numbers just to raise revenue.

Re:Social hack - use "bullfight" for "speed trap". (3, Insightful)

springbox (853816) | more than 7 years ago | (#18834529)

Contrary to the opinion of nearly every jerkwad driver on the interstate, approaching 100 MPH is not "reasonable" or safe.

Re:Social hack - use "bullfight" for "speed trap". (2, Interesting)

Loconut1389 (455297) | more than 7 years ago | (#18834621)

Interstate 35 through most of Iowa is 70 MPH (as of a year or two ago, yay!) - but you hit Ankeny (going south from Ames) and it goes to 65, and then you get about 2 miles before des moines and it goes to 55 without any real change in environment (eg for no real reason). When you've been going 70, 55 is hard to do sometimes- or easy to not notice you're going nearly 20 mph over.

I don't mind them hiding, but it does suck when you're going 62 in that stupid 55 section. Most won't get you for 5 mph, but 7 seems to be the magic number most places I've been/been stopped.

Re: Social hack - use "bullfight" for "speed trap" (0)

Anonymous Coward | more than 7 years ago | (#18834693)

You beat the SHIT out of that strawman. Good show.

Now for an encore, drive from Jacksonville, FL to the city of Atlantic Beach keeping an even, steady speed.

Make sure to make a crack about cops and their moustaches.

Re:Social hack - use "bullfight" for "speed trap". (5, Insightful)

icebrain (944107) | more than 7 years ago | (#18834723)

I never said 100mph was safe or reasonable... but there are many, many places where the road can (and does, every day) handle traffic safely at 70-75 instead of the posted 55, or 45-50 instead of a posted 35 (excluding residential areas). Many of these restrictions are due to arbitrary laws that say, in essence, "speed limits must be X within Y miles of a city", with no regard to the actual road or what it could safely handle.

Look up the video sometime of when a bunch of college students lined up across I-285 in Atlanta and did the posted speed limit (55). Traffic backed up for MILES behind them.

A much bigger threat than pure speed is people who don't pay attention, and realize "Oh crap, that's my exit, four lanes away!" and proceed to cut across said four lanes. Or those who don't bother to check their blind spots when changing lanes, or don't realize that their lane is ending, or don't signal... or insist on driving slow in the left lanes.

And again... if the purpose of limits really was to promote safety, cops wouldn't have to hide. And there would be no penalty for warning others of a speed trap, either. They don't arrest you for saying to someone, "don't rob a bank, the police will get you!" so why should saying "don't drive fast, you'll get a ticket" be any different? Oh, wait, then the local government won't get its traffic fine revenue... and God forbid that the residents pay for their government themselves...

Re:Social hack - use "bullfight" for "speed trap". (-1, Flamebait)

garcia (6573) | more than 7 years ago | (#18834451)

Or alternatively they could find a different way of creating revenue than setting speed traps for a 1/2 mile in and out of town.

Don't talk like you are all high and mighty when you don't have a clue what you're talking about.

Re:Social hack - use "bullfight" for "speed trap". (0)

Anonymous Coward | more than 7 years ago | (#18834525)

Or alternatively, you could just drive the speed limit.


So portforward , do you always drive the speed limit? Didn't think so.

Re:Social hack - use "bullfight" for "speed trap". (2, Funny)

Deagol (323173) | more than 7 years ago | (#18834645)

Some of us actually *do* drive the speed limit. I sure do. Not necessarily because I think the limits/laws are just, but I'll be damned if I'm giving any more of my money to the State or my damned insurance agent. And I plan my trips accordingly.

To that end, not much brings a smile to my face more than driving at the speed limit on cruise control (which I always do) in the passing lane, and pissing-off some Type-A driver who thinks he can sleep in 30 minutes later before his morning commute and make up for it by breaking the law. No, I don't habitually sit in the passing lane, but riding my ass is not going to influence me to go over the speed limit as I inch past that 18-wheeler that's going 74 MPH on the interstate when I'm going 75. If anything, someone tailgating me is usually treated to my slowing down -- one 1-MPH click on the cruise control panel at a time. :)

Re:Social hack - use "bullfight" for "speed trap". (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#18834675)

you're a fuckwit, and I want to slowly torture you to death.

Re:Social hack - use "bullfight" for "speed trap". (1)

drsquare (530038) | more than 7 years ago | (#18834643)

Why? The speed limits are stupidly low. You have a duty to break stupid laws. If the speed limit was 5mph, would you follow it?

Re:Social hack - use "bullfight" for "speed trap". (0)

metalligoth (672285) | more than 7 years ago | (#18834739)

Many municipalities intentionally keep the speed limits low to generate revenue. There's a town here in Michigan that gets the overwhelming majority of the city budget from traffic fines. When speed limits are kept low not for safety but rather for other purposes (such as the to give police the ability to selectively pull people over based on appearance) they are not serving the public and the public has the right to commit civil disobedience by not obeying the speed limit, en masse.

Re:Social hack - use "bullfight" for "speed trap". (3, Informative)

arivanov (12034) | more than 7 years ago | (#18833705)

How uninspiring and unoriginal. Based on my recollections from a brief encounter with Ohio cops 16 years ago I am not surprised in the slightest.

They should come here across the pond to introduce themselves to the most recent inventions in motorist taxation like:

The "Accident Assistance Van" and "Yellow Speed Camera Partnership Van". Both are in use by Sussex police and anyone driving along the A14 and A12 can see them on regular basis.

These vans can be parked with a laser speedgun + CCTV pointed through a window (back, side and front), can be parked behind a hedge with the same laser speedgun + CCTV as the only thing visible on a tripod cabled to the hidden van and most importantly can drive at 3 mph under the speed limit and record the speeds of all who overtake them showing van speed and overtaking vehicle speed.

I have seen them used in every single one of these modes of operation. In fact, out of all my A14 journeys in the last month there has been only one where I have not seen one them. None of them has proper police markings.

Re:Social hack - use "bullfight" for "speed trap". (1)

dave420 (699308) | more than 7 years ago | (#18834241)

If you're speeding, you deserve a ticket. It's that simple. Whether the cop's hiding or not does not affect the guilt of the individual. If the municipalities get so much of an income, then that's purely down to people speeding. Speeding is selfish, and frowned upon for a good reason.

Re:Social hack - use "bullfight" for "speed trap". (1)

sahonen (680948) | more than 7 years ago | (#18834291)

So if the speed limit is set artificially low, you deserve a speeding ticket even if you're travelling at a safe and reasonable speed for the conditions. Got it. People speed because most speed limits are set artifically low to bring in speeding ticket revenue. It's not as bad as 30mph on a freeway, but it's bad enough that travelling the speed limit can be inconvenient.

Re:Social hack - use "bullfight" for "speed trap". (0, Troll)

icebrain (944107) | more than 7 years ago | (#18834349)

So unreasonably slow speed limits should be tolerated just because, well, some bureaucrat decided on some number? Because a town didn't want to have to fund its own operations, but wanted to catch revenue from out-of-state drivers instead?

We should put up with municipalities publicly announcing that they've lowered every speed limit in town because they were in a funding crunch? Multiple speed limit changes over short distances in order to catch people? Look, if the purpose of a speed limit was really to encourage safety, towns wouldn't be receiving income from the tickets. Cops wouldn't have to hide to catch people. There wouldn't be stupid restrictions like "speed limits must be X within Y miles of any town"; the limits would actually be set by the maximum safe speed for that road--not just some arbitrary number designed to raise revenue.

I've seen straight, flat, open 4-lane roads with speed limits of 40, in the middle of nowhere. No houses, no businesses, nothing. No logical reason, AT ALL, for that low of a speed limit... except for revenue generation. There are towns in Georgia where nearly half of their revenue comes from traffic fines.

If people should obey the law, the law first has to be fair and reasonable. It may be a bit of an extreme example, but should someone go along with "Jim Crow" laws (racial segregation laws, for those outside the US) just because, well, it's the law?

I'll obey the speed limit when the speed limit is reasonable, and the police don't enforce them just to raise revenue. Until then, fuck 'em.

Re:Social hack - use "bullfight" for "speed trap". (1)

Onno Hovers (219380) | more than 7 years ago | (#18834131)

They use the "police checkpoint" code for this (speed traps) in the Netherlands. There are some other very interesting codes for things like "gunfire on the road", "airplane crash", "high speed chase", "animals on the road", "tornadoes", "tunnel ventilation not working", "gas leak", etc. If you google for AlertC you may find a list.

Re:An even better application: (4, Funny)

RealSurreal (620564) | more than 7 years ago | (#18833385)

Here in the UK I think you'd find it more efficient to broadcast a message when there wasn't a speed trap ahead.

Re:An even better application: (1)

LiquidCoooled (634315) | more than 7 years ago | (#18834661)

Please do not follow the advice of the parent.
The residents of the one remaining unmonitored street would be annoyed.

Re:An even better application: (1)

Rarb (1033684) | more than 7 years ago | (#18834747)

An idea I've had for a while is to have radar detectors broadcast their "finds" to other radar detectors nearby, such that motorists would have an earlier warning. If each detector could broadcast a "primary-alert" to other units within, say, a half-mile range and those units in turn could broadcast a "secondary-alert" to other units within another half-mile range then a "suitably equipped motorist" could avoid radar guns over a mile away.

A couple of issues that restrict this idea are:
1) The marketing momentum required to establish this kind of "radar detector network". This idea won't work until there are lots of motorists using a detector of this type.
2) Legal issues - many countries and USA states ban the use of radar detectors - it's likely that even more would ban the use of "networkable" radar detectors.

An extension of the whole idea of course, is a tie-in with in-car GPS units, such that the detector could broadcast the precise GPS coordinates of the radar gun, that could be displayed on GPS units in the area.

Now, where's that patent form ...

mportant seems to be missing from tomato soup (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18832869)

HELLO IS THIS WHERE I AM ON THE INTERNEST AND CAN SEND ELMAILS? please help me fix my internet on the computer i am your friend,

I am replyeing to you who said that I was oof topi (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18832937)

How coukd I be off the tpocic that I was talking about on? Why do you minus on me one because if you don't even know me I thout I said I was youhnr friend in the internest?

a& (0, Troll)

Cockmongler (1091711) | more than 7 years ago | (#18833297)

aRLO

rkjvm sakmr8_(*^N WQ*oty5 (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18834217)

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  krsgasfkgj sakljdg sdfg sdfjgh ukjhrkjgn asru hdsaf hugha uhg ara uaewrih a faiesrgufa bajr gsjd hg rjkglzdk dghszfdsxb
a ryhjzxdfkl gjadxkbn foijdvjb gddxiklgja odxfij df iei hgdlkgc f kjlgfafgk jalkglk rgklja fsd gasgjadslkg
a ghsdlgjsdlr;fgl; h;alfgadfgk addzrksx guse5 ijh iyu358ghehu887woh5 85 8h58 hg qp34h g48h 38th rhtq83 h gh qhgr fjghah alkshg

FUCK SHITDOT

Now, why would there be... (4, Insightful)

jamestheprogrammer (932405) | more than 7 years ago | (#18832899)

Why would you have a "terrorist attack" code for a traffic warning system? Okay, so I can see how maybe they might close off streets for emergency personnel, but couldn't you just leave the code at that - "Roads Closed"? I mean, if you go telling drivers that there's a terrorist attack ahead of you, they're going to panic, freak out, and maybe get into a car wreck.

Re:Now, why would there be... (5, Funny)

HerrEkberg (971000) | more than 7 years ago | (#18832925)

That's the point of the "terrorist attack" code. Terrorists use it to create havoc, panic and destruction.

Re:Now, why would there be... (5, Funny)

UbuntuDupe (970646) | more than 7 years ago | (#18833093)

Yeah, good point. But WE are smarter than them. So ... hm, what to do. OH!!!! I know! If there's ever a terrorist attack, all of the news networks should just ignore it entirely! That way people will be in complete ignorance that it's happened. (I mean, except maybe for eyewitnesses calling friends and relatives, but that can easily be banned.)

I mean, informing people about terrorist attacks is just playing into their hands.

Re:Now, why would there be... (1)

revengebomber (1080189) | more than 7 years ago | (#18834743)

The sad part is that this is actually true to some extent; Osama + friends are probably laughing their asses off at how much we have to put up with at airports now.

Re:Now, why would there be... (1)

Jah-Wren Ryel (80510) | more than 7 years ago | (#18834893)

I mean, informing people about terrorist attacks is just playing into their hands.
No, but sensationalizing the news reporting is. Did we really need to have regularly programming constantly interrupted during the day because of the recent college shootings? What benefit was there to completely pre-empting much of that day's prime-time programming with 'news' shows pontificating on every little detail of the event?

Re:Now, why would there be... (1)

The_mad_linguist (1019680) | more than 7 years ago | (#18833173)

The code itself is a terrorist attack?

Genius!

The evil bit (2, Interesting)

gr8dude (832945) | more than 7 years ago | (#18833263)

Hmm.. works exactly like the evil bit [wikipedia.org] . In fact, I'm sure that when they broadcast "terrorist code", somewhere in a lower-level function the evil bit is set too!

Re:Now, why would there be... (1)

Snatch422 (896695) | more than 7 years ago | (#18834035)

So to the point of the "bullfight ahead" code. The Spanish use it to generate revenue by getting everyone excited for some bloody bullfighting [wikipedia.org] ... if only every sport had a GPS code for their events.

Re:Now, why would there be... (1)

rhizome (115711) | more than 7 years ago | (#18834263)

That's the point of the "terrorist attack" code. Terrorists use it to create havoc, panic and destruction.

Wait, I thought that was Dick Cheney's job.

Re:Now, why would there be... (1)

Frosty Piss (770223) | more than 7 years ago | (#18832947)

Why would you have a "terrorist attack" code for a traffic warning system?

The idea, James, is that people could nefariously disrupt the public with messages designed to cause hysteria.

Re:Remember Boston (4, Funny)

arthurpaliden (939626) | more than 7 years ago | (#18832987)

Because the device has batteries, wires and flashing lights so therefore it must be a terrorist device, hence the code.

Re:Now, why would there be... (2, Funny)

hattig (47930) | more than 7 years ago | (#18833097)

I don't think they'd panic.

They'd merely alter their route so they could meerkat the carnage as they drove past. Heavens Forbid that they miss the chance to see such a disaster with their very own eyes, driving past at 10mph looking to the side rather than straight ahead. Wow, is that a dead body? That's something to tell the kids tonight!

Re:Now, why would there be... (1)

joto (134244) | more than 7 years ago | (#18833135)

Why would you have a "terrorist attack" code for a traffic warning system? Okay, so I can see how maybe they might close off streets for emergency personnel, but couldn't you just leave the code at that - "Roads Closed"? I mean, if you go telling drivers that there's a terrorist attack ahead of you, they're going to panic, freak out, and maybe get into a car wreck.

The emergency personnel is also driving by GPS. When they see a "roadblock" code, they try to find a different route. If they see a "terrorist attack" code, they know they are on the correct course.

Do you have any other questions?

Re:Now, why would there be... (1, Insightful)

Anonymous Coward | more than 7 years ago | (#18833477)

Ambulances are dispatched. If they are responding to a terrorist attack, they would have been given a location and would know why there would be a 'road block'. Its like saying that an ambulance can't respond to an accident because the roads around the incident were stated as being closed off.

Re:Now, why would there be... (1)

Achromatic1978 (916097) | more than 7 years ago | (#18833527)

That's silly. How do you think Emergency Dispatch works? Give your ambulance crews a GPS and tell them to drive around till they hit a road which is flagged by the traffic advisory system as "Injury Accident"?

Or, maybe, just maybe, they're given the exact location and enter that, and drive directly there, regardless of what traffic advisories they see?

Re:Now, why would there be... (0)

Anonymous Coward | more than 7 years ago | (#18834017)

The only way to eliminate the need for a "terrorist warning" is to eliminate all religious fucktards out there, including the xtians. Then there would be no need for any warning as there would only be Atheists. ATHEISM FTW! WOOOOOOOOOOOOOOOOOOOOOOOT!

Re:Now, why would there be... (1)

WarlockD (623872) | more than 7 years ago | (#18834461)

I have a Garmin C340 with the traffic updater. I remember one day, the entire city lit up, with major traffic eveywhere. It made me wonder if someone was playing a trick.

Not sure how much prank value this thing has. Not many people use this feature, not to mention its not very up to date when it comes to traffic.

Alternatives (2, Funny)

Anonymous Coward | more than 7 years ago | (#18832935)

It would be much more fun to try for "Jelly wrestling ahead" and watch people panic TOWARDS the area.

Re:Alternatives (1)

CosmeticLobotamy (155360) | more than 7 years ago | (#18832969)

Grape wins!

Re:Alternatives (0)

Anonymous Coward | more than 7 years ago | (#18833005)

Perhaps the "Free beer ahead", makes people move faster.

Advertising tool... (1)

Frosty Piss (770223) | more than 7 years ago | (#18832965)

Years ago (going on 30 years ago, now), I used to hitch-hike. It was safe then. This would be great for that sort of thing. But I can also see this becoming an annoying advertising tool.

Re:Advertising tool... (2, Insightful)

zCyl (14362) | more than 7 years ago | (#18833103)

But I can also see this becoming an annoying advertising tool.

I doubt it. You can also broadcast bogus FM radio station signals containing your own advertisements, because News Flash: FM radio is also not authenticated.

But in the U.S. the FCC regulates these sort of things, and would not take kindly to you broadcasting all over the spectrum without authorization.

Re:Advertising tool... (1)

Frosty Piss (770223) | more than 7 years ago | (#18833155)

But in the U.S. the FCC regulates these sort of things, and would not take kindly to you broadcasting all over the spectrum without authorization.

Who said anything about "unauthorized"? Where there is money to be made by big biz, the FCC is "on-board".

Re:Advertising tool... (1)

Random Destruction (866027) | more than 7 years ago | (#18833337)

In which case they can start their advertising-only radio stations whenever they want.

Re:Advertising tool... (1)

Frosty Piss (770223) | more than 7 years ago | (#18833371)

In which case they can start their advertising-only radio stations whenever they want.

Which will transmit advertising directly to your GPS...

Re:Advertising tool... (1)

KDR_11k (778916) | more than 7 years ago | (#18833559)

The GPS unit's message system most likely uses a registered frequency since it's meant for large area broadcasts.

Re:Advertising tool... (1)

Frosty Piss (770223) | more than 7 years ago | (#18833579)

The GPS unit's message system most likely uses a registered frequency since it's meant for large area broadcasts.

And you seem to think the GPS manufacturers will want to be left out of the cash bonanza? Get used to the idea, advertising is coming to your low end consumer GPS.

Re:Advertising tool... (1)

Onno Hovers (219380) | more than 7 years ago | (#18834315)

The traffic info is sent as a set of numbers. One number is the event code. It ranges from 0 to 2048. Another number is the location code. The map on your navigation device contains a mapping of location codes to roads.

The event code is translated into a human readable text by your navigation device. That text depends on the language you use. So when you get the code "3 km stationary traffic" a German driver will see something like "3km Stau". So you can't put any advertising in that.

However, the RDS station name is sent as text. And it is often abused, as that is what car radios show. France recently passed a law that prohibited putting anything other than the name of the radio station in that field.

Re:Advertising tool... (3, Insightful)

Dun Malg (230075) | more than 7 years ago | (#18833273)

Years ago (going on 30 years ago, now), I used to hitch-hike. It was safe then.
Please. It's still just as safe as it always was (i.e. perfectly safe, unless you're unlucky or alone and female). You think the odd itinerant serial killer didn't used to pick up and murder hitchhikers in the 70's? I can cite you DOZENS of hitchhiker murders from the 70's. The only difference now is that you hear about it on the news, and advances forensic science have led to more conclusions of "definitely murdered hitchhiker", rather than the old separate results of "family in Oregon never hears from hitchhiker again" and "police unable to ID body found by Hwy 8 in Ohio".

Re:Advertising tool... (1)

Loconut1389 (455297) | more than 7 years ago | (#18834733)

Problem is, nobody picks up hitchhikers anymore. Living in Iowa, I've helped a few students waiting at bus stops get to class faster, but I certainly wouldn't/don't stop for people with sleeping bags and an outstretched thumb on the highway. For one, it's illegal to stop for anything other than an emergency on most interstates. Hitchhiking just isn't a viable means anymore. Too many laws and too much paranoia. I think most people are worried about the hitchhiker being a problem, not the other way around.

encryption cant help.. (5, Insightful)

vasanth (908280) | more than 7 years ago | (#18832973)

the writer seems to think encryption can solve this problem, encryption cant help here as the system is unable to communicate back to negotiate the setup, and if the signals are encrypted with a predetermined key it will be susceptible to replay attacks... how different is this to a common radio channel telling its listeners that there's been a terrorist attack etc? the issue seems to be more of a hype than a real concern...

Re:encryption cant help.. (3, Interesting)

WolfWithoutAClause (162946) | more than 7 years ago | (#18833035)

It [i]could[/i] work if public key encryption was used for authentication, and the messages were timestamped and geolocated to prevent replay attacks.

Re:encryption cant help.. (1)

joto (134244) | more than 7 years ago | (#18833177)

It [i]could[/i] work if public key encryption was used for authentication, and the messages were timestamped and geolocated to prevent replay attacks.

Uhm, either all GPS devices and all such public service transmitters would need the encryption code, which is not secure. Or, the process would rely on users actually typing in the public part of an authentication code for the area they visited, which would mean the system would never work because most users would find that a hassle.

Re:encryption cant help.. (1, Informative)

Anonymous Coward | more than 7 years ago | (#18833289)

You don't actually understand how public key encryption works, do you?

The public key is distributed far and wide, embedded in every GPS receiver in fact. This public key can can only decrypt message encrypted with a specific private key, which is not distributed.

Won't work (0)

Anonymous Coward | more than 7 years ago | (#18833471)

You don't actually understand the public key infrastructure problem, don't you?

There needs to be some way for the GPS receiver to receive the public keys. This is not solved just with embedding a fixed set of keys for every GPS receiver, because the set of keys in existence will change, either through the addition of new keys of the cancellation of compromised keys. So, you are going to need to communicate changes to the devices, and this is either impractical or unsecure.

Re:encryption cant help.. (0)

Anonymous Coward | more than 7 years ago | (#18833475)

The GP was probably referring to the fact that a lot of different sources legitimately send these messages, so many people would have access to some (private) keys, making a leak very likely.

Re:encryption cant help.. (1)

joto (134244) | more than 7 years ago | (#18833513)

So exactly how are you going to broadcast these signals? Either someone must give you a private key, or you must make a new one. If someone hands over their private key (because your paperwork is good enough), it's not secure (see CSS on DVD). If you must make a new one, GPS owners need to enter the public key by themselves, which doesn't work. Either way, you are fucked.

Re:encryption cant help.. (1)

DaleGlass (1068434) | more than 7 years ago | (#18833601)

You do it the same way SSL certificates work.

The traffic advisory organization runs a Certificate Authority. They have their private key, which they keep well safe. Subdivisions that need to broadcast messages get their keys signed by the CA, then use them to sign messages. GPS device checks that the message is signed by a key signed by the CA.

If a key is compromised, the CA adds it to the revocation list, which for instance could be regularly broadcasted. After hearing the broadcast, GPS devices refuse to accept messages signed with that key, and whoever used the compromised key has to get a new one.

Re:encryption cant help.. (1)

WolfWithoutAClause (162946) | more than 7 years ago | (#18833293)

Well, there could be a single centralised signature authority that signs messages sent to it with a single private key, the centralised authority would have to implement some kind of separate authentication scheme to make sure that they only sign messages from people that are authenticated to help ensure that they don't end up signing messages from bad guys.

It doesn't have to be perfect it just has to be good enough. Perfect security doesn't exist.

Re:encryption cant help.. (0)

Anonymous Coward | more than 7 years ago | (#18833147)

Replay attacks for a GPS device, it would be pretty naive not to time stamp the broadcasts and have the GPS verify the time, which brings us back to the title of the article...

Strangely fitting captcha: securing

Re:encryption cant help.. (1)

Shadowlore (10860) | more than 7 years ago | (#18834341)

That is a result of the focus on security theater instead of real security. When the alleged security is hype, we will see more hype about it's problems, real or imagined.

Re:encryption cant help.. (1)

QuantumFTL (197300) | more than 7 years ago | (#18834473)

If the signals are encrypted with a predetermined key it will be susceptible to replay attacks
Replay attacks could be prevented by making the messages spacetime specific - GPS systems rely on very accurate timekeeping, so it should be easy enough to make GPS units throw away messages that came at times that disagree with the message's own internal time (which could not be altered without breaking the encryption).

I fail to see how this could be successfully replayed under those circumstances.

great potential (1)

Chief Wongoller (1081431) | more than 7 years ago | (#18833031)

There seems to be great marketing value here: general spam; rerouting via new shopping malls etc. Just imagine you're the owener of a gas station with decling sale: all you need to do is send messages that divert more traffic along your street and business picks up. Billbord advertising rates depend on the volume of traffic passing; ok, just re-route traffic when the traffic survey is being done. Late for work? Get everybody else out of your way. Just as long as you ignore your own 'advise' you'll get there on time.

Re:great potential (2, Informative)

billlion (101976) | more than 7 years ago | (#18833071)

I think people are missing the point. It is just data sent over RDS, standard FM radio in cars have this not just Sat Nav systems. Also the original post is inaccurate. Its not Global Positioning System (GPS systems), it is car Sat Nav units, they use GPS+ mapping and routing software to give directions, GPS gives you position (lat long and altitude), and often from that speed and heading etc are calculated.

This could be a good thing (0)

Anonymous Coward | more than 7 years ago | (#18833053)

If my GPS ever says "Terrorist Bullfight Ahead" I am so there. A couple of Tecates and some C4 sounds like the perfect afternoon.

High tech version of shouting "Fire" . (0)

Anonymous Coward | more than 7 years ago | (#18833057)

I am surprised that there are any codes in there for man-made disasters. Why would anyone include a code for "bomb threat"? would'nt all cars in a twenty mile radius get the message?

As 1,000,000 geeks suddenly find a new project (0)

Anonymous Coward | more than 7 years ago | (#18833067)

Thank's for the heads up. I think that many of us here will be quite intrigued by this, and suddenly desire to either individually, or in groups, devise and create such a device, just so that drivers in the middle of New York or London get "Bullfight Ahead" on their GPS.

"Off the shelf" (1)

Dan East (318230) | more than 7 years ago | (#18833131)

I have a hunch that their definition of "off the shelf equipment" varies significantly from that of the average slashdotter.

There are plenty of extremely simple radio transmission that would be even easier to hack. One that comes to mind are the (rather dated) tones broadcast locally to set off EMS / Fire pagers. Another would be the National Weather Service alerts.

Dan East

Re:"Off the shelf" (1)

ScrewMaster (602015) | more than 7 years ago | (#18833557)

On the other hand, one has to weigh the amusement/entertainment factor against the resulting Federal terrorism charges and corresponding prison sentence.

So what? (1)

geekoid (135745) | more than 7 years ago | (#18833187)

You'll have, what maybe one guy do this just to see if it works?

PLease, a little less fearmongering.

Re:So what? (1)

timeOday (582209) | more than 7 years ago | (#18833685)

And what's to stop a pirate radio station from broadcasting false traffic reports or news by regular old analog voice transmission? Nothing. Somehow the world keeps turning.

So.... (1)

abb3w (696381) | more than 7 years ago | (#18833419)

What is the code number for "Martian Invasion"?

Re:So.... (1)

whereverjustice (955731) | more than 7 years ago | (#18833827)

This is an official Department of Motor Vehicles broadcast. All drivers should now go to Case Orange. Repeat: This is an official Department of Motor Vehicles broadcast. All drivers should now go to Case Orange [battlestarwiki.org] .

Sounds familiar... (4, Interesting)

Tim Browse (9263) | more than 7 years ago | (#18833511)

...I still think this [bbc.co.uk] is funnier.

Big deal... (1)

iamacat (583406) | more than 7 years ago | (#18833515)

That's why they are called advisories. In fact, it may be useful to give truck drivers transmitters to warn people that their truck fscked the freeway. FM radio itself is not authenticated and anyone can transmit some urban legends on radiowaves. We just need to remember that not everything is secured and treat outrageous news with a grain of salt.

AWSOME (1)

normuser (1079315) | more than 7 years ago | (#18833517)

This is AWSOME! *digs through junk drawers*

Get warning from GPS/FM, confirm with XM (1)

Secrity (742221) | more than 7 years ago | (#18833537)

My GPS has an FM traffic receiver, but I don't detour because of information provided by it. I get confirmation and further information from XM traffic, then I decide whether to detour or not.

IT'S SPELT NAÏVE! (0)

Anonymous Coward | more than 7 years ago | (#18833585)

When will you fuckers learn that it's spelt with an umlauted i, otherwise it wouldn't be pronounced nye-eve!

Re:IT'S SPELT NAÏVE! (3, Funny)

Goaway (82658) | more than 7 years ago | (#18834127)

"ï" is not an "umlauted i". "Umlaut" is a feature of German and other related languages, where "i" is never umlauted. English does not have umlauts at all. It uses the double-dot symbol to mark a diaeresis, not an umlaut.

This is been a lesson in nitpicking, you fucker.

Re:IT'S SPELT NAÏVE! (0)

Anonymous Coward | more than 7 years ago | (#18834457)

It's spelled "this has been a lesson in nitpicking", my friend.

Re:IT'S SPELT NAÏVE! (1)

Goaway (82658) | more than 7 years ago | (#18834509)

Thanks, but seeing as how I was the one giving the lesson, I already understood it, no?

Shouldn't this have been tagged with HAHA already? (0)

Anonymous Coward | more than 7 years ago | (#18833655)

This does show how unreliable the GPS system is. Use a simple paper map already that is up to date.

Make Commuting Easier (1)

tiny69 (34486) | more than 7 years ago | (#18833883)

I'd like to have something to make my morning commutes quicker. TomTom and a few others can receive traffic reports. If a report of a traffic jam is received, the user is given the option to detour around the traffic jam. Now if I get get everyone to detour around my daily commute route...

Re:Make Commuting Easier (0)

Anonymous Coward | more than 7 years ago | (#18833983)

The Dash Express [dash.net] is supposed to use other devices in the network as a kind of sensor network. It sounds like it would be far more reliable for traffic prediction than TomTom or Garmin. Problem with traffic alerts is that they are only useful when there is an actual incident. Even in that case it depends very much on the cops actually putting on the sensors and reporting back accurate information. This certainly does not work when you just have a plain ol traffic jam.

Looking through the website the express looks like more than vapor-ware. Who knows if it really works.

TV already did it. (1)

YenTheFirst (1056960) | more than 7 years ago | (#18833909)

It was a minor plot point in a Ghost in the Shell: Standalone Complex episode. according to http://en.wikipedia.org/wiki/List_of_Ghost_in_the_ Shell:_Stand_Alone_Complex_episodes [wikipedia.org] , it was the third episode of the first season. Section 9 ends a car chase by telling the suspects car there is construction ahead, and that he should exit the freeway.

Done already (1)

miscz (888242) | more than 7 years ago | (#18833985)

Radio Maryja, polish catholic radio with some extreme views on jews, EU etc (the same thing according to them ;)) used fake RDS for traffic announcements (TA, TP) few years ago. Drivers with RDS-enabled car stereos usually have their radios set to switch to such broadcast automatically so they often had to turn this option off entirely. Radio Maryja doesn't do that anymore, at least here, but there was a time when this was serious problem, they get away with many illegal radio practices :/

I want a satnav that learns (1)

Colin Smith (2679) | more than 7 years ago | (#18834243)

ok so. 7.45 I leave for work every day and every day my satnav tells me the fastest route to take[1] based on the speed limit of the various roads. However, there are traffic lights and traffic on the route suggested, I can't get anywhere near the speed limit... The satnav is operating on incorrect information.

However. It knows the true average speed along those roads at those times of day because it's actually following the route. All it has to do is to store, and use the stored average speed information for that road at that time on that day of the week. It can automatically take a different/faster route if I happen to delay and hit the school run. I want a satnav that learns this average information as it travels.

[1] I use it for the Estimated Time of Arrival and detour features.
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