information:classification, structural:reformatting, structural:scholar_edition, information:filtering
Secure Enclave

The Secure Enclave is a coprocessor found in iOS devices part of the A7 and newer chips used for data protection. It includes the user data pertaining to Touch ID, Face ID, and Apple Pay, among other sensitive data. The purpose of the Secure Enclave is to handle keys and other info such as biometrics that is sensitive enough to not be handled by the Application Processor (AP). It is isolated with a hardware filter so the AP cannot access it. It shares RAM with the AP, but its portion of the RAM (known as TZ0) is encrypted. The secure enclave itself is a flashable 4 MB AKF processor core called the secure enclave processor (SEP) as documented in Apple Patent Application 20130308838. The technology used is similar to ARM's TrustZone/SecurCore but contains proprietary code for Apple KF cores in general and SEP specifically. It is also responsible for generating the UID key on A9 or newer chips that protects user data at rest.