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
|
#/*
# * Copyright (C) 2017 - This file is part of libecc project
# *
# * Authors:
# * Ryad BENADJILA <ryadbenadjila@gmail.com>
# * Arnaud EBALARD <arnaud.ebalard@ssi.gouv.fr>
# * Jean-Pierre FLORI <jean-pierre.flori@ssi.gouv.fr>
# *
# * Contributors:
# * Nicolas VIVET <nicolas.vivet@ssi.gouv.fr>
# * Karim KHALFALLAH <karim.khalfallah@ssi.gouv.fr>
# *
# * This software is licensed under a dual BSD and GPL v2 license.
# * See LICENSE file at the root folder of the project.
# */
import struct, sys
keccak_rc = [
0x0000000000000001, 0x0000000000008082, 0x800000000000808A, 0x8000000080008000,
0x000000000000808B, 0x0000000080000001, 0x8000000080008081, 0x8000000000008009,
0x000000000000008A, 0x0000000000000088, 0x0000000080008009, 0x000000008000000A,
0x000000008000808B, 0x800000000000008B, 0x8000000000008089, 0x8000000000008003,
0x8000000000008002, 0x8000000000000080, 0x000000000000800A, 0x800000008000000A,
0x8000000080008081, 0x8000000000008080, 0x0000000080000001, 0x8000000080008008
]
keccak_rot = [
[ 0, 36, 3, 41, 18 ],
[ 1, 44, 10, 45, 2 ],
[ 62, 6, 43, 15, 61 ],
[ 28, 55, 25, 21, 56 ],
[ 27, 20, 39, 8, 14 ],
]
def is_python_2():
if sys.version_info[0] < 3:
return True
else:
return False
# Keccak function
def keccak_rotl(x, l):
return (((x << l) ^ (x >> (64 - l))) & (2**64-1))
def keccakround(bytestate, rc):
# Import little endian state
state = [0] * 25
for i in range(0, 25):
to_unpack = ''.join(bytestate[(8*i):(8*i)+8])
if is_python_2() == False:
to_unpack = to_unpack.encode('latin-1')
(state[i],) = struct.unpack('<Q', to_unpack)
# Proceed with the KECCAK core
bcd = [0] * 25
# Theta
for i in range(0, 5):
bcd[i] = state[i] ^ state[i + (5*1)] ^ state[i + (5*2)] ^ state[i + (5*3)] ^ state[i + (5*4)]
for i in range(0, 5):
tmp = bcd[(i+4)%5] ^ keccak_rotl(bcd[(i+1)%5], 1)
for j in range(0, 5):
state[i + (5 * j)] = state[i + (5 * j)] ^ tmp
# Rho and Pi
for i in range(0, 5):
for j in range(0, 5):
bcd[j + (5*(((2*i)+(3*j)) % 5))] = keccak_rotl(state[i + (5*j)], keccak_rot[i][j])
# Chi
for i in range(0, 5):
for j in range(0, 5):
state[i + (5*j)] = bcd[i + (5*j)] ^ (~bcd[((i+1)%5) + (5*j)] & bcd[((i+2)%5) + (5*j)])
# Iota
state[0] = state[0] ^ keccak_rc[rc]
# Pack the output state
output = [0] * (25 * 8)
for i in range(0, 25):
packed = struct.pack('<Q', state[i])
if is_python_2() == True:
output[(8*i):(8*i)+1] = packed
else:
output[(8*i):(8*i)+1] = packed.decode('latin-1')
return output
def keccakf(bytestate):
for rnd in range(0, 24):
bytestate = keccakround(bytestate, rnd)
return bytestate
# SHA-3 context class
class Sha3_ctx(object):
def __init__(self, digest_size):
self.digest_size = digest_size / 8
self.block_size = (25*8) - (2 * (digest_size / 8))
self.idx = 0
self.state = [chr(0)] * (25 * 8)
def digest_size(self):
return self.digest_size
def block_size(self):
return self.block_size
def update(self, message):
if (is_python_2() == False):
message = message.decode('latin-1')
for i in range(0, len(message)):
self.state[self.idx] = chr(ord(self.state[self.idx]) ^ ord(message[i]))
self.idx = self.idx + 1
if (self.idx == self.block_size):
self.state = keccakf(self.state)
self.idx = 0
def digest(self):
self.state[self.idx] = chr(ord(self.state[self.idx]) ^ 0x06)
self.state[int(self.block_size - 1)] = chr(ord(self.state[int(self.block_size - 1)]) ^ 0x80)
self.state = keccakf(self.state)
digest = ''.join(self.state[:int(self.digest_size)])
if is_python_2() == False:
digest = digest.encode('latin-1')
return digest
|
