def block_hamming_distance(x, y):
x_bin = rep.DataRep()
y_bin = rep.DataRep()
x_bin.setFromIntList(x)
y_bin.setFromIntList(y)
x_binstr = x_bin.toBinString()
y_binstr = y_bin.toBinString()
diff = 0
for (x_i, y_i) in zip(x_binstr, y_binstr):
if x_i != y_i:
diff += 1
return diff
def decode(ciphertext):
s = rep.DataRep()
s.setFromHexString(ciphertext)
record = dict()
for ch in range(256):
decrypt = s.singleByteXOR(ch)
record[ch] = score_freqs(decrypt)
return max(record.keys(), key=lambda x: record[x])
def decode(text):
s = rep.DataRep()
s.setFromHexString(text)
winner = 0
plaintext = None
for ch in range(256):
decrypt = s.singleByteXOR(ch)
score = score_freqs(decrypt)
if score > winner:
winner = score
plaintext = decrypt
return plaintext, winner
def XORdecode(text):
s = rep.DataRep()
s.setFromIntList(text)
winner = 0
record = dict()
for ch in range(256):
decrypt = s.singleByteXOR(ch)
score = score_freqs(decrypt)
record[ch] = score
if score > winner:
winner = score
xor_key = ch
return xor_key
def __init__(self):
self.data = rep.DataRep()
self.key = rep.DataRep()
self.round_keys = []
import byte_rep as rep plaintext = "Burning 'em, if you ain't quick and nimble\nI go crazy when I hear a cymbal" k = [ord(x) for x in "ICE"] s = rep.DataRep() s.setFromString(plaintext) s.setFromIntList(s.multiByteXOR(k)) print(s.toHexString())
def entropy_vec(v):
return sum([entropy(x) for x in v])
def to_prob_dist(v):
dist = []
for elem in set(v):
dist.append(v.count(elem) / len(v))
return dist
#read file and decode
with open('c8.txt') as _file:
record = dict()
for file_data in _file.readlines():
data = rep.DataRep()
data.setFromHexString(file_data.rstrip())
# turn into probability distribution and record entropy
record[file_data] = entropy_vec(to_prob_dist(data.toIntList()))
# print line with lowest entropy
print(min(record.keys(), key=lambda x: record[x]))