The only point I'm making is that Apple already designed a cryptosystem that resists court-ordered coercion: as long as your passcode is strong (and Apple has allowed it to be strong for a long time), the phone is prohibitively difficult to unlock even if Apple cuts a special release of the phone software.

Some corps require or strongly encourage it. My employer does.

And most parents I know use alphanumeric to keep their kids from wiping their phones and iPads just by tapping the numbers. (A four digit number code auto-submits on the 4th tap, so all it takes is 40 toddler taps. An alphanumeric code can be any length and won't submit unless the actual submit button is tapped.)

If you have a stronger passcode, you see a full keyboard instead.

Copying a good fingerprint from a dead finger or a randomly placed print is not easy [2]. It's hard, doable but you get 5 tries so if you screw up, you have thrown away all the hard work of the print transfer.

All bets are off if the iPhone is power-cycled. Best bet if you're pulled over by authorities or at a security checkpoint is to turn off your iPhone (and have a strong alphanumeric passcode).

[1] https://xkcd.com/538/ [2] https://blog.lookout.com/blog/2013/09/23/why-i-hacked-apples...

Excellent advice. Even better, if you're about to pass through US customs and border patrol, backup the phone first, wipe, and restore on the other side. Of course, this depends on your level of paranoia. I am paranoid.

I recommend you make a backup to your laptop, which you then encrypt manually. That way the trust model is: you trust yourself. Then you can do whatever you want with the encrypted file. Apple's iCloud is perfectly fine at this point.

The real challenge is to find a way to restore that backup, because you have to be on a computer you trust. If you decrypt the backup on a "loaner" laptop, your security is broken.

If you decrypt the backup on your personal laptop but the laptop has a hidden keylogger installed by the TSA or TAO, your security is broken.

It would be necessary to backup the phone on the _phone_ _itself_. Then manually encrypt the file (easy to do). Then upload to iCloud. At this time, no such app exists for iOS.

Since you plan to restore the backup to the phone anyway, it's no problem to decrypt a file on the phone before using it for the restore.

You mean your laptop that was manufactured by a 3rd party, with a network card that was manufactured by a 3rd party? And you're using encryption software that, even if it's open source, you probably aren't qualified to code review. I'm not downplaying the benefit of being careful, but unfortunately you can keep doing that pretty much forever.

its not trivial, but its sure easy to do in this day and age.

And it's paranoia if there's a legitimate threat, that's just called due diligence. ;)

Do the docs confirm that there is no way around this? I'd guess generating the encryption key requires the passcode, which is discarded immediately, and Touch ID can only "unlock" a temporarily re-encrypted version which never leaves ephemeral storage?

  If Touch ID is turned off, when a device locks, the keys for Data Protection class
  Complete, which are held in the Secure Enclave, are discarded. The files and keychain
  items in that class are inaccessible until the user unlocks the device by entering his
  or her passcode.

  With Touch ID turned on, the keys are not discarded when the device locks; instead,
  they’re wrapped with a key that is given to the Touch ID subsystem inside the Secure
  Enclave. When a user attempts to unlock the device, if Touch ID recognizes the user’s
  fingerprint, it provides the key for unwrapping the Data Protection keys, and the
  device is unlocked. This process provides additional protection by requiring the
  Data Protection and Touch ID subsystems to cooperate in order to unlock the device.
  The keys needed for Touch ID to unlock the device are lost if the device reboots
  and are discarded by the Secure Enclave after 48 hours or five failed Touch ID
  recognition attempts.

Now Cydia and 3rd party stuff? I have no clue.

If I absolutely had to I just wouldn't take a phone/laptop with me.

I wonder if there is any negative effects associated with being refused entry by a CBP? Could it be the case that if you are refused entry once, that in the future they will be more likely to refuse you entry? If so, that's a fairly significant penalty/power that the CBP person has.

Yes, some categories of non-citizen visitors (I don't remember which) are asked on the form if they have ever been refused entry to the U.S. (and are required to answer yes or no). If they're using the same passport number as before, CBP likely also has access to a computerized record of the previous interaction.

(They might also be able to search their database by biographical details such as date of birth, so getting a different passport may not prevent them from guessing that you're the same person.)

You get plenty of tries to perfect the technique, before using it on the actual device.

You acquire identical hardware and "dead finger countermeasures" (does the iphone employ any? Some readers look for pulses and whatnot, I don't know if the iphone does). You then practice reading the fingerprint on that hardware until you are able to reliably get a clean print and bypass any countermeasures. Only then do you try using the finger on the target phone.

You might still fuck it up, and you only get 5 chances on the target hardware. But with practice on the right hardware, I see no reason why you couldn't get it.

https://support.apple.com/en-us/HT204587

Great design.

  All bets are off if the iPhone is power-cycled.

Also remember that rubber-hose cryptanalysis is always an option.

Edit: Looks like the answer is it depends and not a resounding no

http://www.nolo.com/legal-encyclopedia/evidence-obtained-thr...

Examples:

* prolonged solitary confinement: not legally torture

* fellow prisoner violence: not legally torture, no nexus

* prolonged pre-trial confinement: not really torture, but we may as well include it

* waterboarding/drowning: not legally torture? (Supreme Court declined to rule)

* stress positions: cannot show it took place

* parallel construction: cannot show / not aware

If they can find a judge who believes the iron maiden isn't torture while the anal pear is, then guess what... the government will use the iron maiden.

Even if they can't find such a pliable jurist, they'll have no problem getting a John Yoo to write an executive memo that justifies whatever they want to do to you, and let the courts sort it out later. There's no downside from their point of view.

The memos didn't provide de iure indemnity. There is no constitutional basis, in fact the proposition that a memo can supersede the Constitution is idiotic on its face.

The failure is the de facto doctrine of absolute executive immunity. It has two prongs: 1. "When the president does it, that means that it is not illegal." 2. When the perpetrator follows president's orders, also not illegal.

Nevertheless, since there is no legal basis, there is nothing preventing the next government from prosecuting them.

Yes, and that's what I meant by "let the courts sort it out later." The Constitution's not much help either way, being full of imprecise, hand-waving language and vague terms like "cruel and unusual." It was anticipated by the Constitution's authors that it would be of use only to a moral government.

Nevertheless, since there is no legal basis, there is nothing preventing the next government from prosecuting them.

I wonder if that's ever happened in the US? Does anyone know?

It usually only happens when the rule of law is suspended and then resumed. You're a young country, so maybe it hasn't happened before. Robert H. Jackson was an American, though ;-)

Enter parallel-constructed information as court-sanitized evidence.

The pulse and skin conductivity might change, but are either of those reliable enough metrics for such an application?

There is a VERY limited amount of time in which you can take the watch off and switch to another wrist (like milliseconds, you have to practically be a magician to switch wrists (which I do throughout the day)).

Apple has the watch, they could use it to beef up security for those that want it.