def snipeDecrypt(signature, cbkey, block, encryption):
siglen = len(signature)
if encryption:
xorcypherdata = block[:16]
cypherdata = byte_xor(cbkey, xorcypherdata)
data = decrypt(cypherdata, encryption)
if data[:siglen] == signature:
return True
else:
sigcandidate = block[:siglen]
if byte_xor(sigcandidate, cbkey) == signature:
return True
return False
def testDecrypt(bkey, block):
count = 0
for subblock in grouper(16, block):
dec = byte_xor(bkey, subblock)
if dec == zeroBytes:
count += 1
return count
def testSpeedInformedDecrypt(cbkey, block, encryption):
for subblock in grouper(16, block):
crypdec = byte_xor(cbkey, subblock)
if encryption:
dec = decrypt(crypdec, encryption)
else:
dec = crypdec
if dec == zeroBytes:
return True
return False
def testSpeedDecrypt(bkey, block):
for subblock in grouper(16, block):
dec = byte_xor(bkey, subblock)
if dec == zeroBytes:
return True
return False
def xorDecrypt(bkey, block):
return byte_xor(cycle(bkey), block)