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Always-on Processor magic: How Find My works while iPhone is powered off

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111–120 of 267 posts

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#111
post #15

Very interesting read. This seems to be implemented as a Bluetooth LE app running on the ultra-low power “always on processor” used for a variety of features, like “wake-up on motion.” Much like an Tile or AirTag is implemented. No comment on what this is capable in the future.. but for now this shows power usage / signal strength / proximity of other “actually on” devices are a limitations of this feature. What’s im…

Just a simple question. Do you believe in freedom of speech? In freedom of the press? If yes, why do you think it would be shocking if you are spied on?

You are being spied on at this moment. So what are you going to do?

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#112
post #14

Is Matthew Green some industry security personality that people respect? I appreciate this write up, it's interesting. But it seems motivated by his little Twitter rant the other day. Who is he beyond some Twitizen in a Guy Fawkes mask who hates HN? I don't particularly like his demeanor, at least from his rather naively uninformed tantrum the other day. Didn't seem very professional or respectable so I just wrote hi…

Matthew Green wrote zerocash, the protocol behind zcash, and he teaches cryptography at John Hopkins. When it comes to cryptography he knows enough to have opinions. It's hard to opine about black box systems, which is why open-source is so important. It's hard to trust what you can't verify.

Offline finding isn’t a black box system, though. It was presented at Black Hat, and there is a well-known 3rd party implementation. This feature brings offline finding to more cases.

In addition, if this person is a well-regarded professional, then indignant tweeting is even more concerning because the general public has no way of knowing that they’re just misinformed.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#113

Earlier quoted context omitted.

The chances of you being directly spied on are low. The chances of someone being spied on who could influence the world around you is much higher. So a journalist could be spied on right before they break a big story, potentially leading to a cover up. That’s the problem with stuff like this. Even if you have “nothing to hide” you might rely on someone who legitimately does.

Can you be more specific with where you think the risk is? As far as I can tell, in this scenario, the journalist has powered off their phone, ignored the message about "findable when power off," and then is somehow tracked through the BT beacon and Find My network. Were their phone to be on, all the same tracking would work. Were they to read the message and go change the settings, this tracking would presumably not…

You asked what the real risk is then described several risks.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#114
post #4

Earlier quoted context omitted.

Why would they waste their time on Bluetooth tracking when your location pings cell towers and WiFi hotspots?

Perhaps because the bluetooth tracking is a lot more accurate. But since not even Apple can access the data (or so they claim), this shouldn’t be useful for surveillance.

Bluetooth tracking is noisy and a waste of time for external actors because you can't match it other data points.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#115
post #10

Do not try and power off the device. That’s impossible. Instead... only try to realize the truth. The truth? There is no off. From the Matrix, or something.

Well, you can just put your phone in a drawer and go do something else.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#116
post #15

Very interesting read. This seems to be implemented as a Bluetooth LE app running on the ultra-low power “always on processor” used for a variety of features, like “wake-up on motion.” Much like an Tile or AirTag is implemented. No comment on what this is capable in the future.. but for now this shows power usage / signal strength / proximity of other “actually on” devices are a limitations of this feature. What’s im…

The chances of you being directly spied on are low. The chances of someone being spied on who could influence the world around you is much higher. So a journalist could be spied on right before they break a big story, potentially leading to a cover up. That’s the problem with stuff like this. Even if you have “nothing to hide” you might rely on someone who legitimately does.

Without disagreeing with anything you've said there, even if you /think/ you have nothing to hide now and happen to be correct in practice, it's a terrible assumption to think that you can count on that being true forever.

Imagine you witness a murder in a restaurant, cold blooded and it's dirty cops working for a three letter institution that did it. You want to give evidence like a law abiding, upstanding citizen with nothing to hide. Suddenly you have something to hide despite having done nothing wrong.

"Nothing to hide" means nothing to hide from all current and future humans who control some small aspect spying on you. Even just control access for 30 seconds. It's nuts. Even if you think every single last one of the current guys are honest and completely competent despite the head of them criminally lying, while under oath, in answer to a question with notice in legitimate oversight. Who is going to infiltrate that power in 10 years? Radical anti-fa is impossible? White supremacists impossible? Religious cultists? Organised crime? People flipped to work for hostile foreign nations?

"I have nothing to hide" is is gradeschool silliness to be treated with contempt every time it comes up. It needs to be ridiculed as anyone suggesting it is an idiot or just totally and knowingly dishonest. There are just so many ways it is completely wrong, the only debate is which of the ways it is false and a con is more important than the other.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#117
post #5

I like a lot apple products and how they achieved popularizing many technologies, being the next one LIDAR but, for the first time ever I feel this is just going way too far. Sure I want to find my stolen phone even when it is off, but it is way too much loss of freedom having a permanent personal tracker even when the phone is off…

It literally tells you about this right next to the slider to turn off. If you tap the message it lets you turn it off. I see absolutely no issues with this.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#118
post #99

Earlier quoted context omitted.

> Yes which supports all kinds of functionality that people like. Just because you have a processor on or mic listening for wake words doesn’t mean everything is always being transmitted or evil is being done. No, but it means that I’m losing agency in whether or not those things can happen. That’s not ok and not benign.

The 'listen for music' feature on pixel phones is optional and off by default.

Yes, I have a Pixel 3 and can confirm that the feature is off by default; I turned it on for a while to experiment and then turned it off again. Also, it appears that if you turn it on, it compares what it hears against a much smaller set of popular songs (probably comparing against a set of feature vectors that's already on the phone); the search for anything obscure tends to work only if the Google Assistant is used.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#119

Earlier quoted context omitted.

Can you be more specific with where you think the risk is? As far as I can tell, in this scenario, the journalist has powered off their phone, ignored the message about "findable when power off," and then is somehow tracked through the BT beacon and Find My network. Were their phone to be on, all the same tracking would work. Were they to read the message and go change the settings, this tracking would presumably not…

You asked what the real risk is then described several risks.

How many risks here are new in iOS 15 or exclusive to Apple products?

Specifically, I believe the real risk seems to be that you have very few ways to know if your device is doing anything when it's on or off unless the manufacturer tells you.

If you don't believe that everyone, including your government is corrupt, the only solution is through government regulation. Clearly the private companies are otherwise going to do what they will.

Re: Always-on Processor magic: How Find My works while iPhone is powered off

#120
post #76

Earlier quoted context omitted.

Swappable battery is a trend that should return- to both phones and electric vehicles.

As long as the timeframe scales with the size of the battery. A phone battery should be swappable in a few minutes. A car battery should be swappable in a day or two. They have to be heavily shielded in case of an accident.

> A car battery should be swappable in a day or two

Nio currently swaps out their car batteries in about 3 minutes, much like you'd get an oil change at Jiffy Lube or something. It's completely automated except someone pulls the car in/out of the bay for you. I imagine that human step will be relatively short lived.

> they have to be heavily shielded in case of an accident.

Yes, it's just a simple matter of purposefully designing it to be removed easily.

This is cued up to where he gets to the battery swap station: https://youtu.be/hTsrDpsYHrw?t=358

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