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Hacking a parking ticket system

ronreiter.com

1–10 of 65 posts

Re: Hacking a parking ticket system

#6
A really simple "hack" of a car park with an entry barrier that issues you a ticket is that you can usually exit the car park with an unpaid ticket if it's under 10 min old. So just get a new ticket from the entrance when you want to leave.

They do this so you can get out if there are no spaces.

I haven't done this myself and don't condone it. You will probably get in trouble and it's not nice.

Re: Hacking a parking ticket system

#7

A really simple "hack" of a car park with an entry barrier that issues you a ticket is that you can usually exit the car park with an unpaid ticket if it's under 10 min old. So just get a new ticket from the entrance when you want to leave. They do this so you can get out if there are no spaces. I haven't done this myself and don't condone it. You will probably get in trouble and it's not nice.

And let's add the legal term for it here, so it's clear what this "hack" actually is: Fraud.

Re: Hacking a parking ticket system

#8

A really simple "hack" of a car park with an entry barrier that issues you a ticket is that you can usually exit the car park with an unpaid ticket if it's under 10 min old. So just get a new ticket from the entrance when you want to leave. They do this so you can get out if there are no spaces. I haven't done this myself and don't condone it. You will probably get in trouble and it's not nice.

> So just get a new ticket from the entrance

Getting a new ticket from the printer before the barrier will be hard if your car is inside the car park. Often the ticket printer will only work if it notices a large metal object (such as a car) in front of the barrier.

Re: Hacking a parking ticket system

#9

A really simple "hack" of a car park with an entry barrier that issues you a ticket is that you can usually exit the car park with an unpaid ticket if it's under 10 min old. So just get a new ticket from the entrance when you want to leave. They do this so you can get out if there are no spaces. I haven't done this myself and don't condone it. You will probably get in trouble and it's not nice.

> So just get a new ticket from the entrance Getting a new ticket from the printer before the barrier will be hard if your car is inside the car park. Often the ticket printer will only work if it notices a large metal object (such as a car) in front of the barrier.

Many automated garages ban motorcycles because they're unable to trigger the sensor.

Re: Hacking a parking ticket system

#10
> I'm sure there's a bit more elegant way to find the missing thousand component, but for me it would be just quicker to do a bit of brute-forcing:

The calculation the author wants is

  LastThreeDigits(secret*23) = 642
that is equivalent to

  secret * 23 == 642 (mod 1000)
that is equivalent to

  secret * 23 + dummy * 1000 = 642
The standard method is to solve this first for 1 instead of 642

  other_secret * 23 + other_dummy * 1000 = 1
and this can be solved with the Extended Euclidean Algorithm: https://en.wikipedia.org/wiki/Extended_Euclidean_algorithm

(But in this case, and with a computer, it's easier the brute force solution.)

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