How to find a lost phone in a no-cell-coverage camping site? • Hacker News Board

Re: How to find a lost phone in a no-cell-coverage camping site?

#21

Post by solardev » Wed, Oct 25, 2023, 11:44 PM UTC

cj wrote: post #15

redox99 wrote: post #8

Earlier quoted context omitted.

Obivously using certificates and TOFU. APs would share the certificate. (That's how it should work, not how it does in practice)

I’ve always wondered how commonly black hats clone and exploit mass deployed public SSIDs like the “xfinitywifi” network you see in all major US cities with xfinity. Presumably you could get a lot of random devices to automatically connect and then hijack DNS to cause trouble.

Even if you hijacked DNS, most things are HTTPS now and you'd have to get a copy of a certificate from a trusted CA.

Re: How to find a lost phone in a no-cell-coverage camping site?

#22

Post by eternityforest » Wed, Oct 25, 2023, 11:45 PM UTC

flashback2199 wrote: post #13

nineteen999 wrote: post #7

Earlier quoted context omitted.

If the SSID and password are the same, how would the phone tell the difference? I don't know. My Fitbit has a "find my phone" feature that uses Bluetooth to tell the Fitbit app on the phone to make a loud whistle. It's kind of handy and ive made use of it several times around my house, but obviously isn't useful outside Bluetooth range.

> If the SSID and password are the same, how would the phone tell the difference MAC address, but devices don't care, by design they will connect if the SSID and encryption type are the same, actually, you can create a mesh wifi network at your house with regular routers or access points by doing so, connecting them with wired ethernet.

Which is a very good thing, otherwise you wouldn't be able to replace a router and have stuff just work.

Re: How to find a lost phone in a no-cell-coverage camping site?

#23

Post by Scoundreller » Wed, Oct 25, 2023, 11:47 PM UTC

dan_linder wrote: post #9

m463 wrote: post #3

I thought "find my" on newer iphones could do local non-cellular location services, like airtags.

They can, but the AirTag has to be "seen" by another connected device and that device must relay the GPS position it was "seen" at. I don't know if Apple IOS is correct enough to log the time and position of AirTags when the device itself is disconnected from a network...

I wonder how well the relay phone does store and forward, I guess it does otherwise AirTags are useless outside of cellular footprint territory.

I guess sometimes a late ping is better than no ping.

Re: How to find a lost phone in a no-cell-coverage camping site?

#24

Post by brink » Wed, Oct 25, 2023, 11:51 PM UTC

marcod wrote: post #4

So, there is no security feature that prevents a phone from connecting to a cloned wifi network??

99.9% of people don't consider this an issue, I'd rather there not be one in the spec. It's just unnecessary complication. If you're the genuinely paranoid 0.1%, write a script.

Re: How to find a lost phone in a no-cell-coverage camping site?

#25

Post by sergers » Wed, Oct 25, 2023, 11:57 PM UTC

dan_linder wrote: post #9

m463 wrote: post #3

I thought "find my" on newer iphones could do local non-cellular location services, like airtags.

They can, but the AirTag has to be "seen" by another connected device and that device must relay the GPS position it was "seen" at. I don't know if Apple IOS is correct enough to log the time and position of AirTags when the device itself is disconnected from a network...

Samsung has their own "offline finding" as they call it, if enabled other Samsung devices/wearables can locate it somehow, brief on how that's done on their site

Re: How to find a lost phone in a no-cell-coverage camping site?

#26

Post by eternityforest » Wed, Oct 25, 2023, 11:58 PM UTC

I wonder how cheap and low power we could make tracking beacons if we didn't actually have to send any data and could accept some privacy risk.

Imagine like, an airtag, but the ID only needs to be 1 byte long, or even just a simple presence signal.

You'd put it on everything you own that's portable and easy to lose. When you want to find it you just search for signals. Maybe it could have an NFC silencing feature. Perhaps it could only activate after 10 minutes of not detecting movement, while also not being near a base station (The base stations would mark a location as the "safe place you won't forget").

So you won't get any interference from anything people are carrying. You won't pick up anything safely stashed where it actually belongs.

But you can quickly sweep an area for any lost property (Which could be good or bad, depending on if it's a helpful security guard or someone who believes in finders keepers looking...).

You wouldn't ever have to receive any data, except to detect base stations, which would only need maybe a 2ft range.

But it wouldn't solve the big issue with losing stuff, detecting when you leave a location without a thing.

Re: How to find a lost phone in a no-cell-coverage camping site?

#27

Post by dzhiurgis » Thu, Oct 26, 2023, 12:00 AM UTC

Walk around shouting Hey Siri

Re: How to find a lost phone in a no-cell-coverage camping site?

#28

Post by askvictor » Thu, Oct 26, 2023, 12:03 AM UTC

What's the difference in signal strength between bluetooth and wifi? I had assumed since they use the same frequency, and usually the same chip and antenna, they would be much the same (perhaps there are regulatory differences between them?) If anything, I'd guess that BLE would be more useful in this case as there is less handshaking, which means on a very poor connection you've got more of a chance of getting some data through.

Re: How to find a lost phone in a no-cell-coverage camping site?

#29

Post by pests » Thu, Oct 26, 2023, 12:12 AM UTC

eternityforest wrote: post #22

flashback2199 wrote: post #13

Earlier quoted context omitted.

> If the SSID and password are the same, how would the phone tell the difference MAC address, but devices don't care, by design they will connect if the SSID and encryption type are the same, actually, you can create a mesh wifi network at your house with regular routers or access points by doing so, connecting them with wired ethernet.

Which is a very good thing, otherwise you wouldn't be able to replace a router and have stuff just work.

The last time I did we did a WiFi password change at my house there were near 100 devices that had to be updated. Such a hassle. Thankfully it's stayed the same over 4 routers and about 7 years.

Re: How to find a lost phone in a no-cell-coverage camping site?

#30

Post by namibj » Thu, Oct 26, 2023, 12:21 AM UTC

flashback2199 wrote: post #13

nineteen999 wrote: post #7

Earlier quoted context omitted.

If the SSID and password are the same, how would the phone tell the difference? I don't know. My Fitbit has a "find my phone" feature that uses Bluetooth to tell the Fitbit app on the phone to make a loud whistle. It's kind of handy and ive made use of it several times around my house, but obviously isn't useful outside Bluetooth range.

> If the SSID and password are the same, how would the phone tell the difference MAC address, but devices don't care, by design they will connect if the SSID and encryption type are the same, actually, you can create a mesh wifi network at your house with regular routers or access points by doing so, connecting them with wired ethernet.

ESSID != BSSID. The former meant for UX, the latter to uniquely identify. Wpa_didn't allows fixing the latter, for example, as needed when you hang out at multiple locations where the wifi has the default ESSID, but of course with distinct passwords. Causes authentication timeout/lockout annoyance if left alone.