def milenage_generate(opc: bytes, amf: bytes, k: bytes, sqn: bytes,
rand: bytes) -> Dict[str, bytes]:
"""Generate an MILENAGE Authentication Tuple."""
m = Milenage(None)
m.set_opc(opc)
mac_a = m.f1(k, rand, sqn, amf)
res, ck, ik, ak = m.f2345(k, rand)
# AUTN = (SQN ^ AK) || AMF || MAC
sqn_ak = xor_buf(sqn, ak)
autn = b''.join([sqn_ak, amf, mac_a])
return {'res': res, 'ck': ck, 'ik': ik, 'autn': autn}
def milenage_auts(opc: bytes, k: bytes, rand: bytes,
auts: bytes) -> Optional[bytes]:
"""Validate AUTS. If successful, returns SQN_MS"""
amf = b'\x00\x00' # TS 33.102 Section 6.3.3
m = Milenage(None)
m.set_opc(opc)
ak = m.f5star(k, rand)
sqn_ak = auts[:6]
sqn = xor_buf(sqn_ak, ak[:6])
mac_s = m.f1star(k, rand, sqn, amf)
if mac_s == auts[6:14]:
return sqn
else:
return False