“apple uses a dedicated chip”
Thanks for the more full discussion. My question to you is how does the owner of the iPhone make the phone decrypt the data?
I am NOT an expert, but the OS encrypts and decrypts automatically as needed. If the phone is turned off, the data is in an encrypted state. Only having logged on as the user can the data be accessed.
fM, thanks for the explanation. cymbeline, I don’t know the design either, but presumably the chip will not release the key to the OS unless the user types a correct passcode. The OS can “register” a passcode with the chip when the user sets or changes it. After that the OS can send a passcode typed by the user to the chip and if it matches, the chip releases the AES key to the hardware which uses it to decrypt needed data. In all other cases the data stays encrypted and the decryption key stays in the chip.
Each time the owner puts in his passcode, the dedicated secure processor in the iPhone recalculates HASH and compares it to the HASH stored in the Secure Enclave, if it matches, it then re-entangles it with the 128 character UUID in the same way it was entangled originally and uses that to decipher whatever parts of the data you need to use at anyone time during your session on the iPhone use.