class MAC_Checker(BasicIntegrity):
def __init__(self, key, encryption="AES", mode="ECB", hash="SHA"):
super(MAC_Checker, self).__init__(hash)
self.decryptobj = BasicEncryption(key, encryption, mode)
def main(self):
while 1:
try:
if self.dataReady("inbox"):
(data, mac) = self.recv("inbox")
checksum = self.decryptobj.decrypt(mac)
if checksum == self.calcHash(data):
self.send(data, "outbox")
else: # we have a hash failure
raise IntegrityError # This mechanism needs improvement
except IntegrityError:
print "Integrity Error"
yield 1
class MAC_Stamper(BasicIntegrity):
""" Provides message authentication only, message is still sent in plain text
"""
def __init__(self, key, encryption="AES", mode="ECB", hash="SHA"):
super(MAC_Stamper,self).__init__(hash)
self.encryptobj = BasicEncryption(key, encryption, mode)
def main(self):
while 1:
if self.dataReady("inbox"):
data = self.recv("inbox")
mac = self.encryptobj.encrypt(self.calcHash(data))
self.send((data, mac), "outbox")
yield 1
def __init__(self, key, encryption="AES", mode="ECB", hash="SHA"):
super(MAC_Checker, self).__init__(hash)
self.decryptobj = BasicEncryption(key, encryption, mode)