Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

OpenSesame – A device that can open fixed-code garage doors in seconds

samy.pl

Post reply on HN
Print view View original

41–50 of 111 posts

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#41

Post by at-fates-hands »

mrb wrote: post #18

Three weeks ago I reverse-engineered my garage door opener wireless protocol. I probed the remote's PCB with a Saleae logic analyzer and found it was a 12-bit code ASK-modulated at 390 MHz with bits encoded as sequences of 10 kHz and 20 kHz pulses. I bought a $13 spare remote to hack it and control the RF transmitter section from my computer through an FT232 sending the ASK signal. I just cut off the digital signal t…

>>> I wonder if there could be commercial interest in cryptographically secure garage door openers?

Probably not. Mainly because breaking a window or crowbarring a door is a lot less expensive and a lot faster.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#42

Post by imaginenore »

kbenson wrote: post #8
zimbu668 wrote: post #3

> It may be time to upgrade your garage door opener. If you're worried about this, make sure your garage door can't be opened with a coat hanger as well: http://lifehacker.com/5549366/how-to-unlock-your-garage-door... Also most of your door locks can probably be opened in a few seconds with the right tools+experience: http://en.wikipedia.org/wiki/Lock_bumping#Use_by_criminals http://www.carkeywholesale.com/wholesale/…

Exactly like computer security, it's not about making it impossible to gain entrance[1], it's about making it both inconvenient enough and require enough skill that it takes longer or is more noticeable, making it more likely the intruder will be noticed, thus raising the likelihood they will be caught. That said, a few seconds is a pretty low bar. Commodity locks should be better than this, for all our sakes. 1: Thi…

That's not exactly like computer security. With computer security you plan for the worst, not the average. That's why even a skilled hacker/coder can't break into banks or major websites on a daily basis.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#44

Post by blacksmith_tb »

mrb wrote: post #18

Three weeks ago I reverse-engineered my garage door opener wireless protocol. I probed the remote's PCB with a Saleae logic analyzer and found it was a 12-bit code ASK-modulated at 390 MHz with bits encoded as sequences of 10 kHz and 20 kHz pulses. I bought a $13 spare remote to hack it and control the RF transmitter section from my computer through an FT232 sending the ASK signal. I just cut off the digital signal t…

Wouldn't it be simplest to refuse more than 4 attempts per minute? I suppose it would sometimes frustrate the owner bungling the code, but stretching out brute-forcing the whole space to hours instead of minutes would make it a lot less appealing to would-be thieves...

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#45

Post by throwaway7767 »

at-fates-hands wrote: post #41
mrb wrote: post #18

Three weeks ago I reverse-engineered my garage door opener wireless protocol. I probed the remote's PCB with a Saleae logic analyzer and found it was a 12-bit code ASK-modulated at 390 MHz with bits encoded as sequences of 10 kHz and 20 kHz pulses. I bought a $13 spare remote to hack it and control the RF transmitter section from my computer through an FT232 sending the ASK signal. I just cut off the digital signal t…

>>> I wonder if there could be commercial interest in cryptographically secure garage door openers? Probably not. Mainly because breaking a window or crowbarring a door is a lot less expensive and a lot faster.

>> I wonder if there could be commercial interest in cryptographically secure garage door openers?

>Probably not. Mainly because breaking a window or crowbarring a door is a lot less expensive and a lot faster.

It's also a lot more likely to attract attention of bystanders.

Another concern may be insurance. In my area of the world, insurance companies generally refuse to pay out for burglaries unless there is evidence of a break-in (a broken window, forced door or something like that). This would likely not be covered. If this kind of device became popular with thieves like the car keyless entry hacks have, I can see there being a demand for something like this.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#46

Post by bitJericho »

billyhoffman wrote: post #39
Joky wrote: post #33

Earlier quoted context omitted.

It reminds me of a friend that never lock his very old car so that no-one will break a window to see if there is something to steal inside.

About 15 years ago, my aunt stopped locking her convertible. She used to, but people would slit the closed top to reach in and unlock the door to look for CDs and such to steal. A few hundred bucks to replace the top was way worse than losing some change and such. Then she switched to a late 90's Miata which had a lockable center storage bin/arm rest.

A relative of mine had to do the same. He's considering sticking those scary spring snakes in the center console as retribution.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#47

Post by tadfisher »

at-fates-hands wrote: post #41
mrb wrote: post #18

Three weeks ago I reverse-engineered my garage door opener wireless protocol. I probed the remote's PCB with a Saleae logic analyzer and found it was a 12-bit code ASK-modulated at 390 MHz with bits encoded as sequences of 10 kHz and 20 kHz pulses. I bought a $13 spare remote to hack it and control the RF transmitter section from my computer through an FT232 sending the ASK signal. I just cut off the digital signal t…

>>> I wonder if there could be commercial interest in cryptographically secure garage door openers? Probably not. Mainly because breaking a window or crowbarring a door is a lot less expensive and a lot faster.

We're already seeing organized theft rings using devices to unlock car doors without breaking in. I don't think it's outside the realm of possibility for the same thing to occur with garage doors.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#48

Post by mikeash »

Joky wrote: post #33
jandrese wrote: post #7

Earlier quoted context omitted.

My parents did the thing where they put keyed deadbolts on all of the doors. So when someone wanted to break in they broke the glass on the door, discovered the deadbolt, broke the glass on another door and discovered the deadbolt, then broke the glass on a third door before yet again being foiled by the deadbolt. Then they broke a window and stole our stuff anyway. Apparently they were professional thieves too, sinc…

It reminds me of a friend that never lock his very old car so that no-one will break a window to see if there is something to steal inside.

I've seen lots of stories of people doing this and then having the window smashed anyway because the thief doesn't even try the door first.

Re: OpenSesame – A device that can open fixed-code garage doors in seconds

#50

Post by Cymen »

mrb wrote: post #18

Three weeks ago I reverse-engineered my garage door opener wireless protocol. I probed the remote's PCB with a Saleae logic analyzer and found it was a 12-bit code ASK-modulated at 390 MHz with bits encoded as sequences of 10 kHz and 20 kHz pulses. I bought a $13 spare remote to hack it and control the RF transmitter section from my computer through an FT232 sending the ASK signal. I just cut off the digital signal t…

Somewhat of a tangent, but I am concerned about the MITM attack on car locks [1]. This kind of attack is being used in my neighborhood in Oakland, California and no doubt other places. I read the reports of "someone is breaking into my car but no windows/locks are broken". Then a couple other people on NextDoor chime in with the same thing and one person reports a woman who is walking around the neighborhood and appears to be the one responsible. A coworker explained a method where one can amplify the signal of the car and/or car key so that the car thinks the key is next to the car and the door unlocks.

The cryptographically secure garage door opener is still susceptible to MITM if the MITM attack is being done purely by amplification of signal, right?

It's almost like the key needs a handshake with the car by some method that is not using radio frequency. I wonder what options that leaves open? So far, I have not thought of one that is convenient (at some point, it is easier to go back to using a physical key to open a physical lock after all).

1. I think there was a post about it here already but I couldn't find it.

Post reply on HN