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It's my backup key for my garage and my office door. I also use the universal remote to change TVs in public spaces occasionally. It's a chunker, so it's not a

It's my backup key for my garage and my office door. I also use the universal remote to change TVs in public spaces occasionally. It's a chunker, so it's not a pocket carry, but I keep it in my backpack. I recently discovered this, which I want to try: https://electroniccats.com/store/flipper-add-on-magspoof/ https://electroniccats.com/store/flipper-add-on-magspoof/

29athrowaway 3y ago
What kind of garage opener do you have? I thought the Flipper zero won't provide that functionality unless you flash the firmware.
- HanClinto 3y ago
  Not terribly difficult to flash the firmware.
  - 29athrowaway 3y ago
    But now you have to trust some random person from GitHub.
    - speedgoose 3y ago
      Almost all software supply chains rely on random persons at some point.
- Eji1700 3y ago
  The part I don't get is even if you flash the firmware, does that mean you can make sure it doesn't make all other remotes fail? My understanding of the whole rolling code system was that you could get a few uses and then you were screwed. If that's not the case I really need to do this because having it handle my tv's, ceiling fans, and garage door would be a nice trick.
  - ec109685 3y ago
    If you have control of the opener, couldn’t you use the door’s learning mode and make it into a real opener?
    - Eji1700 3y ago
      I thought so at first by my initial reading left me somewhat confused on if there's a private key that only certain remotes have or something like that?
      - abcd_f 3y ago
        It's less of a private key and more a random per-remote prng seed that gets set both on the remote and the door controller when they are paired. When you press the button, remote increments its sequence number and send this number, its ID and a hash of all that and the seed to the controller. Controller checks the hash, then checks that seq number is more than last seen for this remote and opens the door. This protects against replay attacks and fairly uncomplicated to implement.
        tkems 3y ago
        This sounds a lot like the KeeLoq algorithm [0] (minus the hashing part). From my research into the rolling code space, I think most remotes don't quite have the CPU/featureset to support a real, secure crypto system with things like SHA, AES, and RSA/ECC. Would love to see one though! [0] https://en.wikipedia.org/wiki/KeeLoq https://en.wikipedia.org/wiki/KeeLoq
    - tkems 3y ago
      For Chamberlain brands [0] there is some research that shows that their rolling code system (Security+ and Security+ 2.0) is quite easy to decode/decrypt [1]. This feature is supported in the flipper firmware, but is restricted (you can't create a custom remote, only clone is supported) without custom firmware. However, I'm sure you could decode a raw capture file if needed in a pinch. [0] https://chamberlaingroup.com/our-brands https://chamberlaingroup.com/our-brands [1] https://github.com/argilo/secplus https://github.com/argilo/secplus
- filoleg 3y ago
  Not the person you are replying to, but I use my flipper for the exact same purpose. Not sure which specific garage opener my apartment building has. But the fob controller the leasing office gave out is way too weak, so i have to sometimes press it many many times and wiggle it in multiple ways until it triggers the garage door. With flipper, it works on the first try. A funny anecdote: after using my flipper for about a year, I encountered another flipper user in my apartment elevator (the elevator requires a keyfob to go to any floor except the ground floor). I talked to him for a bit. Turns out, he manages a bunch of boat storage units here (in Seattle) that all use different keyfobs. So for him, it is just pure convenience to carry a single flipper device as opposed to always having a lot of different physical keyfobs on him, and then shuffling through them in his bag to get the right one.

29athrowaway 3y ago

What kind of garage opener do you have? I thought the Flipper zero won't provide that functionality unless you flash the firmware.

HanClinto 3y ago
Not terribly difficult to flash the firmware.
- 29athrowaway 3y ago
  But now you have to trust some random person from GitHub.
  - speedgoose 3y ago
    Almost all software supply chains rely on random persons at some point.
Eji1700 3y ago
The part I don't get is even if you flash the firmware, does that mean you can make sure it doesn't make all other remotes fail? My understanding of the whole rolling code system was that you could get a few uses and then you were screwed. If that's not the case I really need to do this because having it handle my tv's, ceiling fans, and garage door would be a nice trick.
- ec109685 3y ago
  If you have control of the opener, couldn’t you use the door’s learning mode and make it into a real opener?
  - Eji1700 3y ago
    I thought so at first by my initial reading left me somewhat confused on if there's a private key that only certain remotes have or something like that?
    - abcd_f 3y ago
      It's less of a private key and more a random per-remote prng seed that gets set both on the remote and the door controller when they are paired. When you press the button, remote increments its sequence number and send this number, its ID and a hash of all that and the seed to the controller. Controller checks the hash, then checks that seq number is more than last seen for this remote and opens the door. This protects against replay attacks and fairly uncomplicated to implement.
      - tkems 3y ago
        This sounds a lot like the KeeLoq algorithm [0] (minus the hashing part). From my research into the rolling code space, I think most remotes don't quite have the CPU/featureset to support a real, secure crypto system with things like SHA, AES, and RSA/ECC. Would love to see one though! [0] https://en.wikipedia.org/wiki/KeeLoq https://en.wikipedia.org/wiki/KeeLoq
  - tkems 3y ago
    For Chamberlain brands [0] there is some research that shows that their rolling code system (Security+ and Security+ 2.0) is quite easy to decode/decrypt [1]. This feature is supported in the flipper firmware, but is restricted (you can't create a custom remote, only clone is supported) without custom firmware. However, I'm sure you could decode a raw capture file if needed in a pinch. [0] https://chamberlaingroup.com/our-brands https://chamberlaingroup.com/our-brands [1] https://github.com/argilo/secplus https://github.com/argilo/secplus
filoleg 3y ago
Not the person you are replying to, but I use my flipper for the exact same purpose. Not sure which specific garage opener my apartment building has. But the fob controller the leasing office gave out is way too weak, so i have to sometimes press it many many times and wiggle it in multiple ways until it triggers the garage door. With flipper, it works on the first try. A funny anecdote: after using my flipper for about a year, I encountered another flipper user in my apartment elevator (the elevator requires a keyfob to go to any floor except the ground floor). I talked to him for a bit. Turns out, he manages a bunch of boat storage units here (in Seattle) that all use different keyfobs. So for him, it is just pure convenience to carry a single flipper device as opposed to always having a lot of different physical keyfobs on him, and then shuffling through them in his bag to get the right one.