This EAP method uses nearly all the logic from EAP-AKA. The major
difference is it uses the new key derivation functions for AKA' as
well as the SHA256 MAC calculation.
EAP-AKA' uses SHA256 rather than SHA1 to generate the packet MAC's.
This updates the derive MAC API to take the EAP method type and
correctly use the right SHA variant to derive the MAC.
This is the core key generation code for the AKA' method which
follows RFC 5448. Two new functions are implemented, one for
deriving CK'/IK' and the other for deriving the encryption keys
using CK'/IK'.
