# Based on pyDes 1.2 by Todd Whiteman <http://twhiteman.netfirms.com/des.html>
# It was licensed under "public domain", so we can relicense under the GPL
# Stripped comments, docstrings, and examples
ECB = 0
CBC = 1
class des:
__pc1 = [56, 48, 40, 32, 24, 16, 8,
0, 57, 49, 41, 33, 25, 17,
9, 1, 58, 50, 42, 34, 26,
18, 10, 2, 59, 51, 43, 35,
62, 54, 46, 38, 30, 22, 14,
6, 61, 53, 45, 37, 29, 21,
13, 5, 60, 52, 44, 36, 28,
20, 12, 4, 27, 19, 11, 3
]
__left_rotations = [
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
]
__pc2 = [
13, 16, 10, 23, 0, 4,
2, 27, 14, 5, 20, 9,
22, 18, 11, 3, 25, 7,
15, 6, 26, 19, 12, 1,
40, 51, 30, 36, 46, 54,
29, 39, 50, 44, 32, 47,
43, 48, 38, 55, 33, 52,
45, 41, 49, 35, 28, 31
]
__ip = [57, 49, 41, 33, 25, 17, 9, 1,
59, 51, 43, 35, 27, 19, 11, 3,
61, 53, 45, 37, 29, 21, 13, 5,
63, 55, 47, 39, 31, 23, 15, 7,
56, 48, 40, 32, 24, 16, 8, 0,
58, 50, 42, 34, 26, 18, 10, 2,
60, 52, 44, 36, 28, 20, 12, 4,
62, 54, 46, 38, 30, 22, 14, 6
]
__expansion_table = [
31, 0, 1, 2, 3, 4,
3, 4, 5, 6, 7, 8,
7, 8, 9, 10, 11, 12,
11, 12, 13, 14, 15, 16,
15, 16, 17, 18, 19, 20,
19, 20, 21, 22, 23, 24,
23, 24, 25, 26, 27, 28,
27, 28, 29, 30, 31, 0
]
__sbox = [
[14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13],
[15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9],
[10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12],
[7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14],
[2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3],
[12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13],
[4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12],
[13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11],
]
__p = [
15, 6, 19, 20, 28, 11,
27, 16, 0, 14, 22, 25,
4, 17, 30, 9, 1, 7,
23,13, 31, 26, 2, 8,
18, 12, 29, 5, 21, 10,
3, 24
]
__fp = [
39, 7, 47, 15, 55, 23, 63, 31,
38, 6, 46, 14, 54, 22, 62, 30,
37, 5, 45, 13, 53, 21, 61, 29,
36, 4, 44, 12, 52, 20, 60, 28,
35, 3, 43, 11, 51, 19, 59, 27,
34, 2, 42, 10, 50, 18, 58, 26,
33, 1, 41, 9, 49, 17, 57, 25,
32, 0, 40, 8, 48, 16, 56, 24
]
ENCRYPT = 0x00
DECRYPT = 0x01
def __init__(self, key, mode=ECB, IV=None):
if len(key) != 8:
raise ValueError("Invalid DES key size. Key must be exactly 8 bytes long.")
self.block_size = 8
self.key_size = 8
self.__padding = ''
self.setMode(mode)
if IV:
self.setIV(IV)
self.L = []
self.R = []
self.Kn = [ [0] * 48 ] * 16
self.final = []
self.setKey(key)
def getKey(self):
return self.__key
def setKey(self, key):
self.__key = key
self.__create_sub_keys()
def getMode(self):
return self.__mode
def setMode(self, mode):
self.__mode = mode
def getIV(self):
return self.__iv
def setIV(self, IV):
if not IV or len(IV) != self.block_size:
raise ValueError("Invalid Initial Value (IV), must be a multiple of " + str(self.block_size) + " bytes")
self.__iv = IV
def getPadding(self):
return self.__padding
def __String_to_BitList(self, data):
l = len(data) * 8
result = [0] * l
pos = 0
for c in data:
i = 7
ch = ord(c)
while i >= 0:
if ch & (1 << i) != 0:
result[pos] = 1
else:
result[pos] = 0
pos += 1
i -= 1
return result
def __BitList_to_String(self, data):
result = ''
pos = 0
c = 0
while pos < len(data):
c += data[pos] << (7 - (pos % 8))
if (pos % 8) == 7:
result += chr(c)
c = 0
pos += 1
return result
def __permutate(self, table, block):
return map(lambda x: block[x], table)
def __create_sub_keys(self):
key = self.__permutate(des.__pc1, self.__String_to_BitList(self.getKey()))
i = 0
self.L = key[:28]
self.R = key[28:]
while i < 16:
j = 0
while j < des.__left_rotations[i]:
self.L.append(self.L[0])
del self.L[0]
self.R.append(self.R[0])
del self.R[0]
j += 1
self.Kn[i] = self.__permutate(des.__pc2, self.L + self.R)
i += 1
def __des_crypt(self, block, crypt_type):
block = self.__permutate(des.__ip, block)
self.L = block[:32]
self.R = block[32:]
if crypt_type == des.ENCRYPT:
iteration = 0
iteration_adjustment = 1
else:
iteration = 15
iteration_adjustment = -1
i = 0
while i < 16:
tempR = self.R[:]
self.R = self.__permutate(des.__expansion_table, self.R)
self.R = map(lambda x, y: x ^ y, self.R, self.Kn[iteration])
B = [self.R[:6], self.R[6:12], self.R[12:18], self.R[18:24], self.R[24:30], self.R[30:36], self.R[36:42], self.R[42:]]
j = 0
Bn = [0] * 32
pos = 0
while j < 8:
m = (B[j][0] << 1) + B[j][5]
n = (B[j][1] << 3) + (B[j][2] << 2) + (B[j][3] << 1) + B[j][4]
v = des.__sbox[j][(m << 4) + n]
Bn[pos] = (v & 8) >> 3
Bn[pos + 1] = (v & 4) >> 2
Bn[pos + 2] = (v & 2) >> 1
Bn[pos + 3] = v & 1
pos += 4
j += 1
self.R = self.__permutate(des.__p, Bn)
self.R = map(lambda x, y: x ^ y, self.R, self.L)
self.L = tempR
i += 1
iteration += iteration_adjustment
self.final = self.__permutate(des.__fp, self.R + self.L)
return self.final
def crypt(self, data, crypt_type):
if not data:
return ''
if len(data) % self.block_size != 0:
if crypt_type == des.DECRYPT:
raise ValueError("Invalid data length, data must be a multiple of " + str(self.block_size) + " bytes\n.")
if not self.getPadding():
raise ValueError("Invalid data length, data must be a multiple of " + str(self.block_size) + " bytes\n. Try setting the optional padding character")
else:
data += (self.block_size - (len(data) % self.block_size)) * self.getPadding()
if self.getMode() == CBC:
if self.getIV():
iv = self.__String_to_BitList(self.getIV())
else:
raise ValueError("For CBC mode, you must supply the Initial Value (IV) for ciphering")
i = 0
dict = {}
result = []
while i < len(data):
block = self.__String_to_BitList(data[i:i+8])
if self.getMode() == CBC:
if crypt_type == des.ENCRYPT:
block = map(lambda x, y: x ^ y, block, iv)
processed_block = self.__des_crypt(block, crypt_type)
if crypt_type == des.DECRYPT:
processed_block = map(lambda x, y: x ^ y, processed_block, iv)
iv = block
else:
iv = processed_block
else:
processed_block = self.__des_crypt(block, crypt_type)
result.append(self.__BitList_to_String(processed_block))
i += 8
if crypt_type == des.DECRYPT and self.getPadding():
s = result[-1]
while s[-1] == self.getPadding():
s = s[:-1]
result[-1] = s
return ''.join(result)
def encrypt(self, data, pad=''):
self.__padding = pad
return self.crypt(data, des.ENCRYPT)
def decrypt(self, data, pad=''):
self.__padding = pad
return self.crypt(data, des.DECRYPT)
class triple_des:
def __init__(self, key, mode=ECB, IV=None):
self.block_size = 8
self.setMode(mode)
self.__padding = ''
self.__iv = IV
self.setKey(key)
def getKey(self):
return self.__key
def setKey(self, key):
self.key_size = 24
if len(key) != self.key_size:
if len(key) == 16:
self.key_size = 16
else:
raise ValueError("Invalid triple DES key size. Key must be either 16 or 24 bytes long")
if self.getMode() == CBC:
if not self.getIV():
self.setIV(key[:self.block_size])
if len(self.getIV()) != self.block_size:
raise ValueError("Invalid IV, must be 8 bytes in length")
self.__key1 = des(key[:8], self.getMode(), self.getIV())
self.__key2 = des(key[8:16], self.getMode(), self.getIV())
if self.key_size == 16:
self.__key3 = self.__key1
else:
self.__key3 = des(key[16:], self.getMode(), self.getIV())
self.__key = key
def getMode(self):
return self.__mode
def setMode(self, mode):
self.__mode = mode
def getIV(self):
return self.__iv
def setIV(self, IV):
self.__iv = IV
def encrypt(self, data, pad=''):
if self.getMode() == CBC:
self.__key1.setIV(self.getIV())
self.__key2.setIV(self.getIV())
self.__key3.setIV(self.getIV())
i = 0
result = []
while i < len(data):
block = self.__key1.encrypt(data[i:i+8], pad)
block = self.__key2.decrypt(block)
block = self.__key3.encrypt(block)
self.__key1.setIV(block)
self.__key2.setIV(block)
self.__key3.setIV(block)
result.append(block)
i += 8
return ''.join(result)
else:
data = self.__key1.encrypt(data, pad)
data = self.__key2.decrypt(data)
return self.__key3.encrypt(data)
def decrypt(self, data, pad=''):
if self.getMode() == CBC:
self.__key1.setIV(self.getIV())
self.__key2.setIV(self.getIV())
self.__key3.setIV(self.getIV())
i = 0
result = []
while i < len(data):
iv = data[i:i+8]
block = self.__key3.decrypt(iv)
block = self.__key2.encrypt(block)
block = self.__key1.decrypt(block, pad)
self.__key1.setIV(iv)
self.__key2.setIV(iv)
self.__key3.setIV(iv)
result.append(block)
i += 8
return ''.join(result)
else:
data = self.__key3.decrypt(data)
data = self.__key2.encrypt(data)
return self.__key1.decrypt(data, pad)
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