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| Author |
Message |
dusted
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RFID "Security"
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Jan 20 06:44 UTC 2006 |
I just saw something in the tv this morning, about RFID chips, and was
stunned, some moron actually got one, and he wants to use it to lock /unlock
his car and appartment, and so on.. now, in my logic, if something is
RadioFrequency, you can tap it, without much effort, just some modified RFID
scanner, and bingo, somebodys whole life, record the signal, and send it near
a reciever, and would be able to walk into his appartment.
If im compleatly wrong, please correct me...
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| 15 responses total. |
tod
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response 1 of 15:
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Jan 20 07:21 UTC 2006 |
I'm still waiting for RFID chips with 0 transfats
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fudge
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response 2 of 15:
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Jan 20 11:41 UTC 2006 |
can we have his name and address?
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marcvh
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response 3 of 15:
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Jan 20 15:44 UTC 2006 |
It's not terribly difficult for someone with the appropriate equipment and
skills to pick a conventional lock either.
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aruba
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response 4 of 15:
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Jan 20 20:51 UTC 2006 |
I think if it were that simple, you could do the same with all the RF car
keys out there.
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dusted
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response 5 of 15:
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Jan 23 08:40 UTC 2006 |
Well, it IS that simple to do with the rf car keys, wich is why nobody uses
them anymore..
Not that long ago, me and some friends build a bulk scanner into a can, (using
the can as omnidirectional antenna) and threw it into a parking lot, it
triggered almost every alarm, and toggeled all the cars that had rf locks,
most unfortunate, i havent been able to come across the code that was used
for the microprocessor..
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gull
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response 6 of 15:
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Jan 25 04:44 UTC 2006 |
The RF key fobs for cars at least have *some* security features, albeit
weak ones. Most of them use rotating codes, like garage door openers.
I think most RFID chips are too simple to have anything like that,
since they're meant to basically be digital barcodes.
The latest thing for luxury cars is a wireless keyfob that's all
automated. You walk up to the car and the doors unlock. You sit down
in the car, press a button on the dash, and it starts. No need to
insert anything or even take it out of your pocket.
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rcurl
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response 7 of 15:
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Jan 25 06:44 UTC 2006 |
Garage door openers have rotating codes? Mine has just dip-switches to set
the code on the remote.
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marcvh
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response 8 of 15:
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Jan 25 06:56 UTC 2006 |
Newer ones have rotating codes, yes, and no dip switches.
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tod
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response 9 of 15:
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Jan 25 16:33 UTC 2006 |
I'd like one of those new rollup garage doors and a rotating fob
opener..that'd be nifty.
For now, we've got one of those big heavy walls that acts like a garage door
with huge metal hinges..and the opener is something you would see atop an
elevator shaft. When the power goes out, I have to get 10 people to help me
get my car out by moving the mammoth door open.
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rcurl
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response 10 of 15:
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Jan 25 18:28 UTC 2006 |
How does the rotating code work? Do both the remote and the opener rotate
the code according to a fixed protocol each time the unit is used? Does
that mean that the remote and opener communicate back and forth
(otherwise, how would Ethe remote know that the opener had responded, and
change its code)? I can also imagine them getting out of "sync". How is
that prevented (or corrected)?
Also, how does this provide better security? Can't someone still scan for
the code until the opener responds?
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marcvh
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response 11 of 15:
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Jan 25 18:46 UTC 2006 |
I don't believe it's a two-way communication stream; I believe that the
remote only transmits and the opener only listens.
My semi-educated guess is that the remote transmits 2 things: a nonce,
and a code such that code = f_k(nonce) where k is the key which is
hard-coded into the remote. Each time you press the button it uses a
different nonce, and so sends a different code. The opener keeps track
of previously-used nonces (they may be strictly sequential or something)
so that replaying a previously used (nonce, code) combination won't open
the door a second time.
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gull
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response 12 of 15:
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Jan 30 04:53 UTC 2006 |
Re resp:11: I think that's essentially correct. There's also a window
of codes the opener will allow, in case the button was pressed a few
times when the remote was out of range of the opener. I believe there's
some kind of failsafe mechanism to get the opener and the remote back
in sync if they get way apart, as well, but I don't remember how it
works. There were details reported back when there was that DMCA
lawsuit about aftermarket opener remotes. These systems are
proprietary, of course, and vary from manufacturer to manufacturer.
The idea of having a rotating feature in the code is so that simply
recording and replaying the transmission won't open the door.
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