The iPhone 5/5C does not have a secure enclave. That was a feature of the A7 chip in the 5S and newer. This is how it's possible for Apple to modify the phone's

The iPhone 5/5C does not have a secure enclave. That was a feature of the A7 chip in the 5S and newer. This is how it's possible for Apple to modify the phone's firmware without wiping the phone. I suspect that the iPhone 5/5C and older's encryption key was stored on a regular flash chip somewhere. edit: the "firmware" update is an iOS update that removes the software limitation. SOFTWARE LIMITATION. On newer iPhones it's hardware (secure enclave). Yes, you can do an firmware update on an encrypted iPhone. It's not full disk encryption. Only user data is encrypted.