def _solve_set3_ch17():
(ciphertext, iv) = cbc_padding_oracle_attack_sample_enc()
block_size = 16
ciphertext = iv + ciphertext
plaintext = ""
while (len(ciphertext) / block_size) > 1:
c0 = ciphertext[-block_size * 2:-block_size]
c1 = ciphertext[-block_size:]
plainblock = ""
for j in range(block_size, 0, -1):
padd_byte = chr(block_size - j + 1)
_c0 = c0[:j] + xor.xor(
c0[j:], xor.xor(plainblock, padd_byte * (ord(padd_byte) - 1)))
flag = False
for k in range(1, 0x100):
scr = "\x00" * (j - 1) + chr(k) + "\x00" * (block_size - j)
if cbc_padding_oracle_attack_sample_dec(
xor.xor(_c0, scr) + c1, iv):
plainblock = xor.xor(chr(k), padd_byte) + plainblock
flag = True
if not flag:
#print "no byte!"
plainblock = padd_byte + plainblock
ciphertext = ciphertext[:-16]
plaintext = plainblock + plaintext
print pkcs7.unpad(plaintext)
def _solve_set2_ch16():
ciphertext = cbc_bitflip_attack_sample_enc("\x00" * 16)
print cbc_bitflip_attack_sample_dec(ciphertext)
C1 = ciphertext[16:32]
p2_ = ";admin=true;;;;;"
p2 = "\x00" * 16
C1_ = xor.xor(xor.xor(C1, p2), p2_)
ciphertext = ciphertext[:16] + C1_ + ciphertext[32:]
print cbc_bitflip_attack_sample_dec(ciphertext)
def __xex(self, data, start, size):
E = AES.new(self.masterKey, AES.MODE_ECB)
c = ""
i = start
for j in range(BLOCK_SIZE):
x = xor(E.encrypt(pack(">QQ", 0, i)), 2**j)
c += xor(xor(E.encrypt(data[j:j + 16], x)), x)
return c
def encrypt_cbc_128(plaintext, iv, key): cipher = AES.new(key, AES.MODE_ECB, "") ciphertext = "" plaintext = pkcs7.pad(plaintext, 16) for i in range(0, len(plaintext) / 16): block = plaintext[16 * i : 16 * (i + 1)] if i == 0: ciphertext = ciphertext + cipher.encrypt(xor.xor(block, iv)) else: prev_block = ciphertext[16 * (i - 1): 16 * i] ciphertext = ciphertext + cipher.encrypt(xor.xor(block, prev_block)) return ciphertext
def read(self, blockNum, size):
E = AES.new(self.masterKey, AES.MODE_ECB)
c = ""
i = blockNum
block = Block()
self.sim.readBlock(self.disk, i, block)
data = block.getData()
for j in range(BLOCK_SIZE()):
x = xor(E.encrypt(pack(">QQ", 0, i)), str(2**j))
c += xor(xor(E.decrypt(data[j:j + 16]), x), x)
return c
def encrypt(self, p):
p = self._padder.pad(p)
c = b""
for i in range(0, len(p), self.block_size):
current_block = p[i:i + self.block_size]
if i == 0:
temp = xor(current_block, self.iv)
c += self._ecb.encrypt(temp)
else:
previous_block = p[i - self.block_size:i]
temp = xor(current_block, previous_block)
c += self._ecb.encrypt(temp)
return c
def decrypt_cbc_128(ciphertext, iv, key, no_unpad = False): cipher = AES.new(key, AES.MODE_ECB, "") plaintext = "" for i in range(0, len(ciphertext) / 16): block = ciphertext[16 * i : 16 * (i + 1)] if i == 0: plaintext = plaintext + xor.xor(cipher.decrypt(block), iv) else: prev_block = ciphertext[16 * (i - 1): 16 * i] plaintext = plaintext + xor.xor(cipher.decrypt(block), prev_block) if no_unpad: return plaintext else: return pkcs7.unpad(plaintext)
def write(self, data, blockNum, size):
#size = int(ceil(float(size) / BLOCK_SIZE()))
#blockNum = self.sim.freeBlock(self.disk, size)
E = AES.new(self.masterKey, AES.MODE_ECB)
c = ""
i = blockNum
print(len(data))
for j in range(BLOCK_SIZE() + 1, 16):
x = xor(E.encrypt(pack(">QQ", 0, i)), str(2**j))
c += xor(xor(E.encrypt(data[j:j + 16]), x), x)
block = Block(c)
self.sim.writeBlock(self.disk, i, block)
return 0
def encrypt(ptext, key, iv):
obj2 = AES.new(key, AES.MODE_ECB)
prev_cipblock=iv
ciptext=bytearray()
#print (len(ptext))
for x in range(0, len(ptext), 16):
#print (x)
pblock=ptext[x:(x+16)]
if len(pblock)<16:
pblock=padding.padding(pblock, 16)
a = xor.xor(pblock, prev_cipblock)
#a = a.decode('UTF-8')
b = obj2.encrypt(bytes(a))
#print (b)
#a = xor.xor(a, prev_cipblock)
#a=a.decode('UTF-8')
ciptext+=b
#print(b)
prev_cipblock=b
#f=input()
return ciptext
def get_possible_plaintexts(ciphertext, keys):
plaintexts = []
for key in keys:
plaintext = unhexlify(xor(ciphertext, key))
plaintexts.append((key[:2], plaintext))
return plaintexts
def hashfun(x): len_x = len(x) hx = '00000000' '''Keep performing XOR operation with consecutive bytes of x''' for i in xrange(0,len_x-8+1,8): hx = xor(hx,x[i:i+8]) return hx.zfill(32)
def hamming_distance(x, y):
bytes = xor(x, y)
collection = ""
for byte in bytes:
collection += "{0:08b}".format(byte)
return collection.count("1")
def test_xor_solution(self):
# cryptopals hex input strings
hex_1 = "1c0111001f010100061a024b53535009181c"
hex_2 = "686974207468652062756c6c277320657965"
# test if it's working
b64_answer = "746865206b696420646f6e277420706c6179"
self.assertEqual(xor.xor(hex_1, hex_2), b64_answer)
def hmac(key, data):
s = sha1()
t = sha1()
ipad = b"\x36" * 64
opad = b"\x5C" * 64
if len(key) < 64:
key += b"\x00" * (64 - len(key))
elif len(key) > 64 * 2:
u = sha1()
u.update(key)
key = u.hexdigest()
key += b"\x00" * (64 - len(key))
s.update(xor(key, ipad) + data)
t.update(xor(key, opad) + s.digest())
return t.hexdigest()
def encryptAES_CBC(decrypt: bytes, key: bytes, iv: bytes):
if len(iv) != 16:
raise ValueError('IV must have a 16 bytes block size.')
decrypt = pad(decrypt, 16)
encrypt = bytes()
for i in range(int(len(decrypt) / 16)):
block = xor(decrypt[i * 16:(i + 1) * 16],
iv if i == 0 else encrypt[(i - 1) * 16:i * 16])
encrypt += encryptAES_ECB(block, key)
return encrypt
def cbc_decrypt(enc, key, iv, block_size=16):
cipher = AES.new(key, AES.MODE_ECB)
dec = ''
prev = iv
for n in range(0, len(enc), block_size):
block = enc[n:n+block_size]
dec_block = cipher.decrypt(block)
dec += xor(dec_block, prev)
prev = block
return dec
def cbc_encrypt(text, key, iv, block_size=16):
cipher = AES.new(key, AES.MODE_ECB)
enc = ''
prev = iv
for n in range(0, len(text), block_size):
block = xor(text[n:n+block_size], prev)
enc_block = cipher.encrypt(block)
enc += enc_block
prev = enc_block
return enc
def decryptAES_CBC(encrypt: bytes, key: bytes, iv: bytes):
if len(iv) != 16:
raise ValueError('IV must have a 16 bytes block size.')
if len(encrypt) % 16 != 0:
raise ValueError('The encrypted data must be 16 bytes padded.')
middecrypt = pad(decryptAES_ECB(encrypt, key), 16)
decrypt = bytes()
for i in range(int(len(encrypt) / 16)):
decrypt += xor(middecrypt[i * 16:(i + 1) * 16],
iv if i == 0 else encrypt[(i - 1) * 16:i * 16])
return unpad(decrypt)
def encrypt(self, iv, plaintext):
bs = self.block_size
lp = len(plaintext)
last = self.encrypt_func(iv)
if lp < bs:
return xor(last[:lp], plaintext)
r = StringIO()
m = len(plaintext) % bs
if m == 0:
for i in xrange(0, lp, bs):
last = self.encrypt_func(xor(last, plaintext[i:i + bs]))
r.write(last)
else:
for i in xrange(0, lp - bs - m, bs):
last = self.encrypt_func(xor(last, plaintext[i:i + bs]))
r.write(last)
cn = self.encrypt_func(xor(last, plaintext[-bs-m:-m]))
r.write(self.encrypt_func(xor(cn, plaintext[-m:] + ('\000' * (bs - m)))))
r.write(cn[:m])
return r.getvalue()
def get_hamming_distance(hex_str1, hex_str2):
xor_res = xor(hex_str1, hex_str2)
xor_res = unhexlify(xor_res)
hamming_distance = 0
for byte in xor_res:
bits = bin(byte)
hamming_distance += bits.count("1")
hamming_distance /= len(xor_res)
return hamming_distance
def decrypt(self, c):
"""
Reverse the encrypt operation.
The encrypt operation first xors the current and previous block, and then performs
the encryption. In order to decrypt this data, we need to reverse that procedure;
first, decrypt a block of c, then xor it. This will result in p.
:param c:
:return:
"""
p = b""
for i in range(0, len(c), self.block_size):
current_block = c[i:i + self.block_size]
if i == 0:
temp = self._ecb.decrypt(current_block)
p += xor(temp, self.iv)
else:
previous_block = c[i - self.block_size:i]
temp = self._ecb.decrypt(current_block)
p += xor(temp, previous_block)
p = self._padder.unpad(p)
return p
def encrypt(self, iv, plaintext):
bs = self.block_size
lp = len(plaintext)
last = self.encrypt_func(iv)
if lp < bs:
return xor(last[:lp], plaintext)
r = StringIO()
m = len(plaintext) % bs
if m == 0:
for i in xrange(0, lp, bs):
last = self.encrypt_func(xor(last, plaintext[i:i + bs]))
r.write(last)
else:
for i in xrange(0, lp - bs - m, bs):
last = self.encrypt_func(xor(last, plaintext[i:i + bs]))
r.write(last)
cn = self.encrypt_func(xor(last, plaintext[-bs - m:-m]))
r.write(
self.encrypt_func(xor(cn,
plaintext[-m:] + ('\000' * (bs - m)))))
r.write(cn[:m])
return r.getvalue()
def decrypt(self, iv, ciphertext):
bs = self.block_size
lc = len(ciphertext)
last = self.encrypt_func(iv)
if lc < bs:
return xor(last[:lc], ciphertext)
r = StringIO()
m = len(ciphertext) % bs
if m == 0:
for i in xrange(0, lc, bs):
nl = ciphertext[i:i + bs]
r.write(xor(last, self.decrypt_func(nl)))
last = nl
else:
for i in xrange(0, lc - bs - m, bs):
nl = ciphertext[i:i + bs]
r.write(xor(last, self.decrypt_func(nl)))
last = nl
pn = xor(self.decrypt_func(ciphertext[-bs-m:-m]), ciphertext[-m:] + ('\000' * (bs - m)))
r.write(xor(last, self.decrypt_func(ciphertext[-m:] + pn[m:])))
r.write(pn[:m])
return r.getvalue()
def decrypt(self, iv, ciphertext):
bs = self.block_size
lc = len(ciphertext)
last = self.encrypt_func(iv)
if lc < bs:
return xor(last[:lc], ciphertext)
r = StringIO()
m = len(ciphertext) % bs
if m == 0:
for i in xrange(0, lc, bs):
nl = ciphertext[i:i + bs]
r.write(xor(last, self.decrypt_func(nl)))
last = nl
else:
for i in xrange(0, lc - bs - m, bs):
nl = ciphertext[i:i + bs]
r.write(xor(last, self.decrypt_func(nl)))
last = nl
pn = xor(self.decrypt_func(ciphertext[-bs - m:-m]),
ciphertext[-m:] + ('\000' * (bs - m)))
r.write(xor(last, self.decrypt_func(ciphertext[-m:] + pn[m:])))
r.write(pn[:m])
return r.getvalue()
def degenerate_check(ciphertext: Term,
previous_ciphertexts: List[Term]) -> bool:
"""
Check if symbolic history is degenerate
"""
degen = False
previous_ciphertexts.append(ciphertext)
seq = zero
for t in previous_ciphertexts:
seq = xor(seq, t)
if seq == zero:
degen = True
break
return degen
def cbc_decrypt(c, k, iv):
if len(k) not in (16, 24, 32):
raise Exception('InvalidKeyLength')
if len(c) % 16 != 0:
raise Exception('InvalidCiphertextLength')
if len(iv) != 16:
raise Exception('InvalidIVLength')
p = b''
prev_cblock = iv
for cblock in chunked(c, 16):
cblock = bytes(cblock)
pblock = xor(ecb_decrypt(cblock, k), prev_cblock)
prev_cblock = cblock
p += pblock
return p
def cbc_encrypt(p, k, iv):
if len(k) not in (16, 24, 32):
raise Exception('InvalidKeyLength')
if len(p) % 16 != 0:
raise Exception('InvalidPlaintextLength')
if len(iv) != 16:
raise Exception('InvalidIVLength')
c = b''
prev_cblock = iv
for pblock in chunked(p, 16):
pblock = bytes(pblock)
cblock = ecb_encrypt(xor(pblock, prev_cblock), k)
prev_cblock = cblock
c += cblock
return c
def main():
file_obj = ''
cipherlist = []
with open('files/4.txt') as f:
for line in f:
cipherlist.append(line.strip().decode('hex'))
max_score = 0
max_string = ''
for k in range(0, 255):
key = chr(k)
for i in cipherlist:
x = xor(i, key)
sc = score_text(x)
if sc > max_score:
max_score = sc
max_string = x
print('Final score: {}, string: {}'.format(str(max_score), max_string))
def encrypt_ecb_cbc(message, key, iv):
block_length = len(key)
if len(iv) != block_length:
raise Exception("iv must match key length!")
padded_message = pad(message, block_length)
blocks = list(grouper(padded_message, block_length))
cipher = AES.new(key, AES.MODE_ECB)
last_block = iv
encrypted_blocks = []
for block in blocks:
encrypted_block = cipher.encrypt(xor(last_block, block))
encrypted_blocks.append(encrypted_block)
last_block = encrypted_block
return b"".join(encrypted_blocks)
def decrypt_ecb_cbc(cipher_text, key, iv):
block_length = len(key)
if len(iv) != block_length:
raise Exception("iv must match key length!")
blocks = list(grouper(cipher_text, block_length))
cipher = AES.new(key, AES.MODE_ECB)
last_block = iv
plain_blocks = []
for block in blocks:
decrypted_block = cipher.decrypt(bytes(block))
plain_block = xor(last_block, decrypted_block)
plain_blocks.append(plain_block)
last_block = block
plain_text = pad_strip(b"".join(plain_blocks))
return plain_text
def decrypt_aes_cbc(message, key, iv=(chr(0) * 16).encode()):
'''
Args:
message (bytes): The message to be derypted
key (bytes): The key to use in the decryption
iv (optional bytes): The initialization vector for CBC mode
Return:
Decrypted message
'''
block_size = 16
enc_message = [
message[i:i + block_size] for i in range(0, len(message), block_size)
]
dec_message = []
dec_string = iv
for i in range(0, len(enc_message)):
decrypted = xor(decrypt_aes_ecb(enc_message[i], key), dec_string)
dec_message.append(decrypted.decode())
dec_string = enc_message[i]
return ''.join(dec_message)
def decrypt(ciptext, key, iv):
obj2 = AES.new(key, AES.MODE_ECB)
prev_cipblock=iv
ptext=bytearray()
for x in range(0, len(ciptext), 16):
cipblock=ciptext[x:(x+16)]
#if len(cipblock)<16:
# cipblock=padding.padding(cipblock, 16)
#a = cipblock.decode('Utf-8')
a = obj2.decrypt(bytes(cipblock))
#print (a)
a = xor.xor(a, prev_cipblock)
#a=a.decode('UTF-8')
ptext+=a
#print(a)
x+=16
prev_cipblock=cipblock
#f=input()
return ptext
def encrypt_aes_cbc(message, key, iv=(chr(0) * 16).encode()):
'''
Args:
message (bytes): The message to be encrypted
key (bytes): The key to use in the encrypted
iv (optional bytes): The initialization vector for CBC mode
Return:
Encrypted message
'''
block_size = 16
message = padding(message)
dec_message = [
message[i:i + block_size] for i in range(0, len(message), block_size)
]
enc_message = []
enc_string = iv
for i in range(0, len(dec_message)):
encrypted = encrypt_aes_ecb(xor(dec_message[i], enc_string), key,
False)
enc_message.append(encrypted)
enc_string = enc_message[i]
return b''.join(enc_message)
#!/usr/bin/env python3
# coding: utf-8
"""
Implement repeating-key XOR.
https://cryptopals.com/sets/1/challenges/5
"""
from binascii import hexlify
from xor import xor
ps = ("Burning 'em, if you ain't quick and nimble\n"
"I go crazy when I hear a cymbal")
ks = 'ICE'
p = bytes(ps, 'utf8')
k = bytes(ks, 'utf8')
e = xor(p, k)
print(hexlify(e).decode('utf8'))
def getSingleXORKey(s):
freqtab = {}
frlist = []
f3 = open("freq.txt", "r")
for line in f3:
words = line.split()
freqtab[words[0]] = float(words[1])
frlist.append(words[0])
mindev = 100.000
ans = ""
store = -1
for i in range(0, 256):
a = bytes([i] * (int)(len(s)))
count = 0
flag = 0
dev = 0
warn = 0
freqline = {}
freqline = freqline.fromkeys(frlist, 0)
p = xor.xor(s, a)
#print (p)
try:
p = p.decode('UTF-8')
except Exception:
continue
#print (p)
for j in range(0, len(p)):
c = p[j]
if ord(c) > 31:
if c.isalpha():
count = count + 1
freqline[c.upper()] = freqline[c.upper()] + 1
else:
if (ord(c) != 10):
warn += 1
continue
#break
if flag == 0:
if (count <= 0):
continue
for key in freqline:
freqline[key] = float(freqline[key]) / float(count)
dev = dev + abs(freqline[key] - freqtab[key])
dev = dev / float(count)
dev += warn
#print (dev)
#print (i)
if dev < mindev:
ans = p
mindev = dev
store = i
f3.close()
#print (mindev)
return (ans, store, mindev)
def test_Xor_Str1OddLength_Succeeds(self):
test_str1 = "11111"
test_str2 = "2222"
with self.assertRaises(ValueError):
xor(test_str1, test_str2)
#Demande au serveur à l'URL de CHALLENGE
reponse_challenge = server.query(url_challenge)
#On récupère le champ A -> normalement en UTF-8, il faut décoder l'hexadécimal en bytes, puis de bytes en unicode
AxorM = reponse_challenge['A']
#On récupère le champ B -> normalement en ASCII, il faut décoder l'hexadécimal en bytes, puis de bytes en ascii
BxorM = reponse_challenge['B']
#Transformation en bytes pour A et B
AxorM_decode = base64.b16decode(AxorM, casefold=True)
BxorM_decode = base64.b16decode(BxorM, casefold=True)
#Calcul du XOR entre A et B (en bytes) -> élimination du masque M
AxorB = xor(AxorM_decode, BxorM_decode)
length_AxorB = len(AxorB)
msg_AxorB = ""
#Recherche du message avec Xor sur 0
for i in range(0, length_AxorB):
c = chr(xor_byte(AxorB[i], ord('0')))
if (c.isalpha() == False) and c != "\n" and c != " " :
c = chr(xor_byte(AxorB[i], ord('1')))
msg_AxorB += str(c)
#Impression des deux messages
#print("msg 0 : {0}".format(msg_AxorB_0))
#print("msg 1 : {0}".format(msg_AxorB_1))
tup=prob3.getSingleXORKey(s)
#print (len(tup))
if(tup[1]==-1):
flag=1
print ("Failed : "+ str(keysize))
break
keys.append(tup[1])
dev+=tup[2]
if flag==1:
continue
ans=xor.xor((bigstring.encode('UTF-8')), keys)
dev = float(dev)/keysize
ans=ans.decode('UTF-8')
#print (ans)
print (keysize)
print(keys)
print (dev/keysize)
import sys
import xor
import convert
import binascii
f1 = open("input5.txt", "r")
s = f1.read()
k = input("Enter key:")
s=s.encode("utf-8")
k = k.encode("utf-8")
p = xor.xor(s, k)
p = binascii.hexlify(p)
print (p)
f2 = open("output5.txt", "w")
f2.write(str(p))
f2.close()
f1.close()
def halfadder(a, b):
return {'c':aand(a,b),'o':xor(a,b)}
def xnor(a, b):
return nnot(xor(a,b))
import sys import convert import xor import binascii a = "1c0111001f010100061a024b53535009181c" b = "686974207468652062756c6c277320657965" a = binascii.unhexlify(a) b = binascii.unhexlify(b) c = xor.xor(a, b) #c = convert.binarytohex(c) print (binascii.hexlify(c))
linecur=0
for line in f2:
linecur+=1
line = line.rstrip('\n')
#print line
#k = raw_input()
s = binascii.unhexlify(line)
#print (s)
for i in range(0, 256):
a = bytes([i]*(int)(len(s)))
count=0
flag=0
dev=0
freqline={}
freqline = freqline.fromkeys(frlist, 0)
p = xor.xor(s, a)
try:
p = p.decode("utf-8")
except Exception:
#print ("Here")
continue
#print p
#print (p)
for j in range(0, len(p)):
c = p[j]
if ord(c)>31 and ord(c)<127 or ord(c)==10:
if c.isalpha():
count=count+1
freqline[c.upper()]=freqline[c.upper()]+1
import sys
import collections
manpage = """ matrix of Xor files : python matrix.py [ list of files ] """
get_array = lambda m,i: [ m[j][i] for j in range(0, len(m)) if i < len(m[j]) ]
get_printable = lambda array: filter(lambda c: c in xor.printable, array)
get_printable_with_zero = lambda array: filter(lambda c: 0 != ord(c) or c in xor.printable, array)
most_common_image = lambda m: [ collections.Counter(get_printable(get_array(m,i))).most_common(1) if len([x for x in get_printable(get_array(m,i))]) < 3/4.0*len([x for x in get_printable_with_zero(get_array(m,i))]) else (' ',0) for i in range(clen) ]
if __name__ == '__main__':
if not len(sys.argv):
print(manpage)
else:
m = []
for i in range(2, len(sys.argv)):
x = xor.xor(open(sys.argv[1], "rb").read(), open(sys.argv[i], "rb").read())
m.append(x)
# print (xor.hex_escape(','.join(x)))
clen = len(open(sys.argv[1], "rb").read())
# "Most Frequent for " + sys.argv[1] + " : " +
print(''.join( t[0][0] if t != [] else '?' for t in most_common_image(m) ))