1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
|
# Python PRIDE implementation
# Version: 1.0
# Date: 22/04/2015
#
# =============================================================================
#
# Python implementation of the PRIDE cipher
# Copyright (C) 2015 Camil Staps (info@camilstaps.nl)
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# =============================================================================
class Pride:
def __init__(self,key):
"""Create a PRIDE cipher object
key: the key as a 128-bit raw string"""
if len(key) * 8 == 128:
self.key_whitening = string2number(key[:8])
self.key_1 = key[8:]
else:
raise ValueError, "Key must be a 128-bit raw string"
def encrypt(self,block):
"""Encrypt 1 block (8 bytes)
Input: plaintext block as raw string
Output: ciphertext block as raw string"""
state = string2number(block)
# Initial permutation & pre-whitening
state = pLayer_dec(state)
state = addRoundKey(state, self.key_whitening)
# 19 rounds R
for i in xrange (1,20):
state = addRoundKey(state, roundKey(self.key_1, i))
state = sBoxLayer(state)
state = lLayer(state)
# Last round R'
state = addRoundKey(state, roundKey(self.key_1, 20))
state = sBoxLayer(state)
# Post-whitening & final permutation
state = addRoundKey(state, self.key_whitening)
state = pLayer(state)
return number2string_N(state,8)
def decrypt(self,block):
"""Decrypt 1 block (8 bytes)
Input: ciphertext block as raw string
Output: plaintex block as raw string"""
state = string2number(block)
# Final permutation & post-whitening
state = pLayer_dec(state)
state = addRoundKey(state, self.key_whitening)
# Last round R'
state = sBoxLayer_dec(state)
state = addRoundKey(state, roundKey(self.key_1, 20))
# 19 rounds R
for i in xrange(19,0,-1):
state = lLayer_dec(state)
state = sBoxLayer_dec(state)
state = addRoundKey(state, roundKey(self.key_1, i))
# Pre-whitening & initial permutation
state = addRoundKey(state, self.key_whitening)
state = pLayer(state)
return number2string_N(state,8)
# 4 to 4-bit S-Box and its inverse
Sbox= [0x0,0x4,0x8,0xf,0x1,0x5,0xe,0x9,0x2,0x7,0xa,0xc,0xb,0xd,0x6,0x3]
Sbox_inv = [Sbox.index(x) for x in xrange(16)]
# 64-bit permutation P and its inverse
PBox = [0,16,32,48,1,17,33,49,2,18,34,50,3,19,35,51,4,20,36,52,5,21,37,53,6,22,38,54,7,23,39,55,8,24,40,56,9,25,41,57,10,26,42,58,11,27,43,59,12,28,44,60,13,29,45,61,14,30,46,62,15,31,47,63]
PBox_inv = [PBox.index(x) for x in xrange(64)]
# Matrices for permutation in the L layer
L0 = [[0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0],
[0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0],
[0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0],
[0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1],
[1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0],
[0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0],
[0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0],
[0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1],
[1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0],
[0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0],
[0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0],
[0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1],
[1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0],
[0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0],
[0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0],
[0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0]]
L0_inv = L0
L1 = [[1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0],
[0,1,1,0,0,0,0,0,0,0,0,0,1,0,0,0],
[0,0,1,1,0,0,0,0,0,0,0,0,0,1,0,0],
[0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,0],
[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1],
[0,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0],
[0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,0],
[1,0,0,0,0,0,0,1,0,0,1,0,0,0,0,0],
[1,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0],
[0,1,0,0,0,0,0,0,0,0,0,0,1,1,0,0],
[0,0,1,0,0,0,0,0,0,0,0,0,0,1,1,0],
[0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,1],
[0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1],
[0,0,0,0,0,1,0,0,1,1,0,0,0,0,0,0],
[0,0,0,0,0,0,1,0,0,1,1,0,0,0,0,0],
[0,0,0,0,0,0,0,1,0,0,1,1,0,0,0,0]]
L1_inv = [[0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0],
[1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1],
[1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0],
[0,1,1,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,0],
[0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,1,0,0,0],
[0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,0],
[0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0],
[0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0],
[0,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0],
[0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,1],
[0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0],
[0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0],
[0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0]]
L2 = [[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1],
[0,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0],
[0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,0],
[1,0,0,0,0,0,0,1,0,0,1,0,0,0,0,0],
[1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0],
[0,1,1,0,0,0,0,0,0,0,0,0,1,0,0,0],
[0,0,1,1,0,0,0,0,0,0,0,0,0,1,0,0],
[0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,0],
[0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1],
[0,0,0,0,0,1,0,0,1,1,0,0,0,0,0,0],
[0,0,0,0,0,0,1,0,0,1,1,0,0,0,0,0],
[0,0,0,0,0,0,0,1,0,0,1,1,0,0,0,0],
[1,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0],
[0,1,0,0,0,0,0,0,0,0,0,0,1,1,0,0],
[0,0,1,0,0,0,0,0,0,0,0,0,0,1,1,0],
[0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,1]]
L2_inv = [[0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,0],
[0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0],
[0,0,0,0,1,1,0,0,0,0,0,0,1,0,0,0],
[0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,0],
[0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0],
[1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1],
[1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0],
[0,1,1,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0],
[0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0],
[0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0],
[0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0],
[0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0],
[0,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0],
[0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,1]]
L3 = [[1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0],
[0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0],
[0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0],
[0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1],
[1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0],
[0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0],
[0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0],
[0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0],
[0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0],
[0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0],
[0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0],
[0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1],
[1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0],
[0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0],
[0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0],
[0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1]]
L3_inv = L3
def mapXor(xs):
"""Xor elements of a list together"""
return reduce(lambda a, b: a^b, xs, 0)
def matrixMultiply(matrix, input):
"""Multiply a vector with a binary matrix
Input: matrix as [[Int]];
input as Int
Output: Int"""
mult = [ mapXor([c * ((input >> (15 - c_i)) & 0x1) for c_i, c in reversed(list(enumerate(r)))]) for r in matrix ]
return sum([(1 << (15-i)) * v for i,v in enumerate(mult)])
def roundKey(key, i):
"""Calculate a round key
Input: the base key (second half of it) as a raw string;
the round number
Output: the round key as raw string"""
return pLayer_dec(string2number(
key[0]
+ chr((ord(key[1]) + 193 * i) % 256)
+ key[2]
+ chr((ord(key[3]) + 165 * i) % 256)
+ key[4]
+ chr((ord(key[5]) + 81 * i) % 256)
+ key[6]
+ chr((ord(key[7]) + 197 * i) % 256)
))
def addRoundKey(state,roundkey):
return state ^ roundkey
def sBoxLayer(state):
"""SBox function for encryption
Input: 64-bit integer
Output: 64-bit integer"""
return sum([Sbox[( state >> (i*4)) & 0xF] << (i*4) for i in xrange(16)])
def sBoxLayer_dec(state):
"""Inverse SBox function for decryption
Input: 64-bit integer
Output: 64-bit integer"""
return sum([Sbox_inv[( state >> (i*4)) & 0xF] << (i*4) for i in xrange(16)])
def pLayer(state):
"""Permutation layer for encryption
Input: 64-bit integer
Output: 64-bit integer"""
return sum ([((state >> i) & 0x01) << PBox[i] for i in xrange(64)])
def pLayer_dec(state):
"""Permutation layer for decryption
Input: 64-bit integer
Output: 64-bit integer"""
return sum ([((state >> i) & 0x01) << PBox_inv[i] for i in xrange(64)])
def lLayer(state):
"""Perform the L layer:
* P (permutation)
* L0 .. L3 on all four 16-bit substrings
* P_inv (permutation inverse)
Input: the current state, as raw string
Output: the new state, as an raw string"""
state = pLayer(state)
state = (matrixMultiply(L0, (state >> 48) & 0xffff) << 48) + (
matrixMultiply(L1, (state >> 32) & 0xffff) << 32) + (
matrixMultiply(L2, (state >> 16) & 0xffff) << 16) + (
matrixMultiply(L3, state & 0xffff))
return pLayer_dec(state)
def lLayer_dec(state):
"""L layer for decryption:
* P (permutation)
* L0_inv .. L3_inv multiplication on the four 16-bit substrings, respectively
* P_inv (permutation inverse)
Input: the current state, as raw string
Output: the new state, as raw string"""
state = pLayer(state)
state = (matrixMultiply(L0_inv, (state >> 48) & 0xffff) << 48) + (
matrixMultiply(L1_inv, (state >> 32) & 0xffff) << 32) + (
matrixMultiply(L2_inv, (state >> 16) & 0xffff) << 16) + (
matrixMultiply(L3_inv, state & 0xffff))
return pLayer_dec(state)
def string2number(i):
""" Convert a string to a number
Input: string (big-endian)
Output: long or integer
"""
return int(i.encode('hex'),16)
def number2string_N(i, N):
"""Convert a number to a string of fixed size
i: long or integer
N: length of string
Output: string (big-endian)
"""
s = '%0*x' % (N*2, i)
return s.decode('hex')
if __name__ == "__main__":
cipher = Pride("0000000000000000fedcba9876543210".decode('hex'))
encryption = cipher.encrypt("0123456789abcdef".decode('hex'))
print encryption.encode('hex')
decryption = cipher.decrypt(encryption)
print decryption.encode('hex')
|
