def verify(self,msgAndDigest):
"""
verifies the result returned by mac
"""
if msgAndDigest['alg'] != self._algorithm:
raise ValueError("Currently only HMAC_SHA1 is supported as an algorithm")
expected = (self.mac(msgAndDigest['msg'])['digest'])
recieved = (msgAndDigest['digest'])
return sha1hashlib(expected).digest() == sha1hashlib(recieved).digest() # we compare the hash instead of the direct value to avoid a timing attack
def verify(self,msgAndDigest):
"""
verifies the result returned by mac
"""
if msgAndDigest['alg'] != self._algorithm:
raise ValueError()
expected = bytes(self.mac(msgAndDigest['msg'])['digest'],'utf-8')
recieved = bytes(msgAndDigest['digest'],'utf-8')
return sha1hashlib(expected).digest() == sha1hashlib(recieved).digest() # we compare the hash instead of the direct value to avoid a timing attack
def verify(self, msgAndDigest):
"""
verifies the result returned by mac
"""
if msgAndDigest['alg'] != self._algorithm:
raise ValueError(
"Currently only HMAC_SHA1 is supported as an algorithm")
expected = (self.mac(msgAndDigest['msg'])['digest'])
recieved = (msgAndDigest['digest'])
return sha1hashlib(expected).digest() == sha1hashlib(recieved).digest(
) # we compare the hash instead of the direct value to avoid a timing attack
def encrypt(self, msg):
mac = MessageAuthenticator(
sha1hashlib(
b'Poor Mans Key Extractor' +
self._key).digest()) # warning only valid in the random oracle
enc = super(AuthenticatedCryptoAbstraction, self).encrypt(msg)
return mac.mac(enc)
def decrypt(self, cipherText):
mac = MessageAuthenticator(
sha1hashlib(
b'Poor Mans Key Extractor' +
self._key).digest()) # warning only valid in the random oracle
if not mac.verify(cipherText):
raise ValueError(
"Invalid mac. Your data was tampered with or your key is wrong"
)
else:
return super(AuthenticatedCryptoAbstraction,
self).decrypt(cipherText['msg'])
def decrypt(self,cipherText):
mac = MessageAuthenticator(sha1hashlib(b'Poor Mans Key Extractor'+self._key).digest()) # warning only valid in the random oracle
if not mac.verify(cipherText):
raise ValueError("Invalid mac. Your data was tampered with or your key is wrong")
else:
return super(AuthenticatedCryptoAbstraction,self).decrypt(cipherText['msg'])
def encrypt(self,msg):
mac = MessageAuthenticator(sha1hashlib(b'Poor Mans Key Extractor'+self._key).digest()) # warning only valid in the random oracle
enc = super(AuthenticatedCryptoAbstraction,self).encrypt(msg)
return mac.mac(enc);
