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I was really excited to get mine! It is neat. I got it and it has been in my drawer almost exclusively. I have done exactly two things with mine:

* Opened my friend's Tesla battery charge hatch from a distance for fun (it closes again on its own after maybe 30 seconds)

* Recorded a lamp's IR remote on/off/up/down toggles and used the Flipper to turn on the lamp, rather than using the IR remote, to try to debug whether the remote was going bad or if there was a problem with the lamp (it was the lamp itself)

And I tried, unsuccessfully, to:

* Read my dog's microchip data

Otherwise, I haven't found any use for it. I really wanted to like it. I did a search to see if there was anything interesting to do with it that I was missing, and basically it's what I did (or failed to do) above. Some people also use it to change TV channels at restaurants as a prank it looks like.

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1/4th of my cats have microchips. They were moderately annoyed as I scanned them.

The whole microchip registry thing is a mess, though. There's no authoritative database and I'm certain that the database entry for my cat is at some shelter where he was briefly held. I have no way of updating this data without paying a subscription fee, so that's out of the question.

Outside of IR remotes and popping tesla ports, I have used it to emulate RFID tags. I don't have enough free time to really utilize it appropriately.

Cat tax: https://i.imgur.com/8vAabRM.jpeg -- He is sleeping where he really should not be sleeping.

https://old.reddit.com/r/CatsOnPizza/

https://old.reddit.com/r/orangecats/

Here's a ML problem for someone to consider tackling ... given a cat picture, identify all of the relevant cat subs that it might get posted in. This could be applied to dogs too... but cats rule the internet ( https://en.wikipedia.org/wiki/Cats_and_the_Internet )

> Here's a ML problem for someone to consider tackling ... given a cat picture, identify all of the relevant cat subs that it might get posted in

I'm fairly certain that there are an infinite number of cat subs, so this task is impossible!

While "yes" ... there are only so many that are big. Getting the top 100 cat subs and going from there would be a nice ballpark number.

Its one of the "this might be a fun thing to do if you're playing with a ML image classification problem."

I've got a Mac and so https://developer.apple.com/documentation/createml/creating-... has tempted me on occasion to see "how much can this thing do?"

you'd have to solve the halting problem?

Nope, that's an issue of psychic barking dogs.

https://everything2.com/title/halting+dog+problem

There's also the incomplete dog issue... https://everything2.com/title/Dog+incompleteness

> The whole microchip registry thing is a mess, though.

That is, unfortunately, correct ^^^ I went through this with my dog. I was told to find out which services your local animal control and humane society use, and make sure your pet is added to those registries. Yes, some charge $$$, but the registries recommended to me were free.

If your pet ends up with animal control, and they can't find the chip registration, getting your pet back can be a nightmare.

And if you move across the country the local animal control / humane society may use different registries.

It's a great idea, in theory, but it's opened up a world where the possibility of scam registries can exist.

I've considered the challenges of an open and public registry, but allowing the public to access it is problematic as there is no way to validate the entries and you would be handling people's contact information. It might be an actual use of a distributed blockchain / public ledger.

Maybe there is no need for a centralized database of contact information, but there could be one for found pets.

Single resource. Any vet/shelter/guy with a RFID scanner can report found pet with this barcode at approximately this location. If you know this pet, contact us here. Presumably only vets and shelters would be adding to the database, so all of the contact information is already public. People who have lost their pets can then monitor this location/sign up for alerts after you lose Fluffy.

Not as great as being able to immediately lookup the owner, but eliminates some privacy concerns.

You couldn't do this with current chips I don't think, but if you had at least 256 bytes of randomness on the chip, you could.

The simplest way to do this would be to use the random data for an EC25519 private key, which would be used to encrypt the data[1] and then sign the encrypted blob plus an unencrypted timestamp. The registry would be a mapping of public keys to encrypted records. Updates could be accomplished by sending a record with a greater timestamp, which would then be propagated to other nodes.

You could also put a DHT on top of that to minimize storage requirements, perhaps also a PoW scheme for sibil resistance.

[1] EC doesn't technically do encryption, but that can be worked around by attaching a public key for an ephemeral keypair for your message, doing a DH against the two keypairs, and using the resulting secret as a key for symmetric encryption.

Or, why have a registry at all? Can't the chip itself hold a few bytes of data for a phone number? I don't know anything about these "chips", but I have to imagine that's possible.

Why would a phone number be useful as a permanent ID for a pet? What if it is rehomed or the owner changes their number? A UUID with a central database or a public/private key with a decentralized database are much better solutions for that.

True, your social security number would make more sense as the primary key.

There is no single authoritative database, but it works kinda like MAC addresses, in that the microchip prefix tells the system who made the chip, which tells them which database to look you up in. You should be able to get the shelter to update the database to match your contact information for you free of charge. At least our shelter was willing to do so. They already have to pay the fee, so why not?

> The whole microchip registry thing is a mess, though. There's no authoritative database and I'm certain that the database entry for my cat is at some shelter where he was briefly held.

Yeah it is a mess, but my vet told me they use this to search across the dozens of registries in the United States: https://www.aaha.org/for-veterinary-professionals/microchip-...

That form is able to find my cat's microchip information in both the registries I have her on, for example. But yes, I was surprised the pet microchip scene isn't more consolidated. Like bicycle registrations are, where the two major U.S. players are https://bikeindex.org and https://project529.com

EDIT: But I was unable to read my cat's microchip with my Flipper Zero, even though my vet confirmed it's still readable using their more appropriate tool for the job.

Can you emulate common TV IR blaster protocols without first recording them?

I used to have an LG G4 android phone with a TV remote app built in- with just the TV manufacturer information, I could change the channel / volume in all sorts of useful places (the gym, etc.). I miss this feature often.

Yep:

"Flipper Zero has a built-in library of signals for common TVs, ACs, projectors, and stereo systems brands. This library is regularly updated with new signals, thanks to the Flipper Zero community's active contributions to the IR Remote database."

(from the flipper zero homepage)

I've successfully used mine as a "TVbGone", switching off all the TVs in a bar...

Thank you, and sorry for being so blind. I think this is enough to sell me on one!

For God knows why reason, the original PSPs used to come with an IR LED. I put a homebrew program on my PSP that let you control it, and fed it a txt file with thousands of TV IR codes. What a blast!

Same experience here. I don't blame the Flipper, though, only my own lack of creativity and energy.

Do you know if I can emulate car keys with it? Say a relatively modern BMW? Or is there some safety mechanism.

(Not for nefarious purposes, but just in case I can’t find my keys.)

Not natively. There is other firmware out there, though, that allows such functionality. Depending on where you live, it may be illegal to even try, though, hence the native firmware locking out such use (you can record or visualize but not save/replay).

Just recording and replaying wouldn’t help you anyways, the code is rolling to prevent replay attacks.

I think if you have enough replays you can deconstruct the rolling code. Not sure.

Also there are ways to desync/resync your key so you might be able to “add a key” with the flipper with certain firmwares.

Cloning the current key and using it can desync it from your car. Super annoying. Be careful

I don’t know exactly how the rolling key works but wouldn’t it be kind of like having a secret stored in the key that’s needed to generate the next code? If it’s designed properly, recording a few thousand codes shouldn’t tell you anything about the next code, just like you can’t deduce private keys by looking at a few thousand encrypted files. I have no clue if that’s really how it works, so I would be happy to be corrected if my mental model is wrong here.

> If it’s designed properly,

That phrase is doing a lot of heave lifting there...

(This is only what I've read, but as i understand it many rolling code keys can be broken by recording three button presses while the keyfob is out of range of the car, then brute forcing the seed.)

Basically yeah. You'd need millions of replays to even have a chance. Cracking basic wifi back in the day required a couple days worth of sniffed packets. I'd imagine this is similar, if there is in fact a way to do it.

Rolling code protocols like Keeloq can be broken pretty easily (apparently).

Plenty of devices use the Keeloq protocol for rolling codes which is pretty straightforward to break in modern hardware.

Emulating the rolling code protocol would desync your keys.

What ever device you’d want to use as a backup would need to capture information sent from the vehicle during the last unlock.

I'd love to have this, mainly so that I could have a single dongle on my keychain for both my and my wife's car. I know others have said that there are issues around rolling codes. But it's possible to get official duplicate / replacement keys; how does that work?

IIRC it's somewhat possible but for some cars if you do it wrong it makes the car and key go out of sync which causes a lot of issues

Don't do it. The key can easily get messed up if the rolling code isn't handled appropriately.

So an attacker can cause your car keys not to work?

Yes, as well as gain access to your vehicle. This has been reported on quite a bit over the last couple of years.

The old Ford transponder keys don't do rolling codes.

So far I have not been able to emulate the keys on either of my cars, a 2001 Ford Ranger and a 2019 Subaru Outback. I think the Ranger is probably possible, but I haven't figured it out yet.

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