4 ms·

Why doesn't the FBI simply clone the current device, make brute force attempts and then clone again if locked out? Yes, lots of work but also doesn't force Appl

Why doesn't the FBI simply clone the current device, make brute force attempts and then clone again if locked out? Yes, lots of work but also doesn't force Apple to participate.

ethbro 11y ago
Would it be infeasible to construct part of the private key out of hardware-specific id's + time-of-creation hashes? I assume it's not only the PIN?
- acdha 11y ago
  That's what the A7 (iPhone 5S and later) design does: “Each Secure Enclave is provisioned during fabrication with its own UID (Unique ID) that is not accessible to other parts of the system and is not known to Apple. When the device starts up, an ephemeral key is created, entangled with its UID, and used to encrypt the Secure Enclave’s portion of the device’s memory space. Additionally, data that is saved to the file system by the Secure Enclave is encrypted with a key entangled with the UID and an anti-replay counter.” https://www.apple.com/business/docs/iOS_Security_Guide.pdf https://www.apple.com/business/docs/iOS_Security_Guide.pdf The device in question is an iPhone 5C, which uses the older A6 design.
  - ethbro 11y ago
    Thanks for the link! I knew there had to be more technical information out there but couldn't find it on an initial search.
    - acdha 11y ago
      Yeah, it wasn't exactly unknown before but it wasn't terribly common outside of certain security / compliance circles. I think I've seen more links today than in the previous year.
pflats 11y ago
I thought @csoghoian's take was interesting. The FBI doesn't want one specific phone unlocked, they want precedent. https://twitter.com/csoghoian/status/699841360963108864 https://twitter.com/csoghoian/status/699841360963108864
ParadoxOryx 11y ago
The iPhone uses AES encryption which would prevent cloning the flash storage [1]. There was an informative discussion of this over on AppleInsider - http://forums.appleinsider.com/discussion/191851 http://forums.appleinsider.com/discussion/191851 [1] http://www.darthnull.org/2014/10/06/ios-encryption http://www.darthnull.org/2014/10/06/ios-encryption
- jobead 11y ago
  from that discussion, super informative details on how secure enclave is actually implemented: http://forums.appleinsider.com/discussion/comment/2832533/#Comment_2832533 http://forums.appleinsider.com/discussion/comment/2832533/#C...
conradev 11y ago
Each device has a device-specific AES key (UID) burned into it such that you cannot clone devices (or move flash chips between them). Everything is encrypted with a derivative of this UID, and extracting the UID is not a thing you can do without destroying the device.

Why doesn't the FBI simply clone the current device, make brute force attempts and then clone again if locked out? Yes, lots of work but also doesn't force Apple to participate.

ethbro 11y ago

Would it be infeasible to construct part of the private key out of hardware-specific id's + time-of-creation hashes? I assume it's not only the PIN?

acdha 11y ago
That's what the A7 (iPhone 5S and later) design does: “Each Secure Enclave is provisioned during fabrication with its own UID (Unique ID) that is not accessible to other parts of the system and is not known to Apple. When the device starts up, an ephemeral key is created, entangled with its UID, and used to encrypt the Secure Enclave’s portion of the device’s memory space. Additionally, data that is saved to the file system by the Secure Enclave is encrypted with a key entangled with the UID and an anti-replay counter.” https://www.apple.com/business/docs/iOS_Security_Guide.pdf https://www.apple.com/business/docs/iOS_Security_Guide.pdf The device in question is an iPhone 5C, which uses the older A6 design.
- ethbro 11y ago
  Thanks for the link! I knew there had to be more technical information out there but couldn't find it on an initial search.
  - acdha 11y ago
    Yeah, it wasn't exactly unknown before but it wasn't terribly common outside of certain security / compliance circles. I think I've seen more links today than in the previous year.

pflats 11y ago

I thought @csoghoian's take was interesting. The FBI doesn't want one specific phone unlocked, they want precedent. https://twitter.com/csoghoian/status/699841360963108864 https://twitter.com/csoghoian/status/699841360963108864

ParadoxOryx 11y ago

The iPhone uses AES encryption which would prevent cloning the flash storage [1]. There was an informative discussion of this over on AppleInsider - http://forums.appleinsider.com/discussion/191851 http://forums.appleinsider.com/discussion/191851 [1] http://www.darthnull.org/2014/10/06/ios-encryption http://www.darthnull.org/2014/10/06/ios-encryption

jobead 11y ago
from that discussion, super informative details on how secure enclave is actually implemented: http://forums.appleinsider.com/discussion/comment/2832533/#Comment_2832533 http://forums.appleinsider.com/discussion/comment/2832533/#C...

conradev 11y ago

Each device has a device-specific AES key (UID) burned into it such that you cannot clone devices (or move flash chips between them). Everything is encrypted with a derivative of this UID, and extracting the UID is not a thing you can do without destroying the device.