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
|
/*************************************************
* KASUMI Source File *
* (C) 1999-2007 Jack Lloyd *
*************************************************/
#include <botan/kasumi.h>
#include <botan/loadstor.h>
#include <botan/bit_ops.h>
namespace Botan {
namespace {
/*************************************************
* KASUMI FI Function *
*************************************************/
u16bit FI(u16bit I, u16bit K)
{
u16bit D9 = (I >> 7);
byte D7 = (I & 0x7F);
D9 = KASUMI_SBOX_S9[D9] ^ D7;
D7 = KASUMI_SBOX_S7[D7] ^ (D9 & 0x7F);
D7 ^= (K >> 9);
D9 = KASUMI_SBOX_S9[D9 ^ (K & 0x1FF)] ^ D7;
D7 = KASUMI_SBOX_S7[D7] ^ (D9 & 0x7F);
return (D7 << 9) | D9;
}
}
/*************************************************
* KASUMI Encryption *
*************************************************/
void KASUMI::enc(const byte in[], byte out[]) const
{
u16bit B0 = load_be<u16bit>(in, 0);
u16bit B1 = load_be<u16bit>(in, 1);
u16bit B2 = load_be<u16bit>(in, 2);
u16bit B3 = load_be<u16bit>(in, 3);
for(u32bit j = 0; j != 8; j += 2)
{
const u16bit* K = EK + 8*j;
u16bit R = B1 ^ (rotate_left(B0, 1) & K[0]);
u16bit L = B0 ^ (rotate_left(R, 1) | K[1]);
L = FI(L ^ K[ 2], K[ 3]) ^ R;
R = FI(R ^ K[ 4], K[ 5]) ^ L;
L = FI(L ^ K[ 6], K[ 7]) ^ R;
R = B2 ^= R;
L = B3 ^= L;
R = FI(R ^ K[10], K[11]) ^ L;
L = FI(L ^ K[12], K[13]) ^ R;
R = FI(R ^ K[14], K[15]) ^ L;
R ^= (rotate_left(L, 1) & K[8]);
L ^= (rotate_left(R, 1) | K[9]);
B0 ^= L;
B1 ^= R;
}
store_be(out, B0, B1, B2, B3);
}
/*************************************************
* KASUMI Decryption *
*************************************************/
void KASUMI::dec(const byte in[], byte out[]) const
{
u16bit B0 = load_be<u16bit>(in, 0);
u16bit B1 = load_be<u16bit>(in, 1);
u16bit B2 = load_be<u16bit>(in, 2);
u16bit B3 = load_be<u16bit>(in, 3);
for(u32bit j = 0; j != 8; j += 2)
{
const u16bit* K = EK + 8*(6-j);
u16bit L = B2, R = B3;
L = FI(L ^ K[10], K[11]) ^ R;
R = FI(R ^ K[12], K[13]) ^ L;
L = FI(L ^ K[14], K[15]) ^ R;
L ^= (rotate_left(R, 1) & K[8]);
R ^= (rotate_left(L, 1) | K[9]);
R = B0 ^= R;
L = B1 ^= L;
L ^= (rotate_left(R, 1) & K[0]);
R ^= (rotate_left(L, 1) | K[1]);
R = FI(R ^ K[2], K[3]) ^ L;
L = FI(L ^ K[4], K[5]) ^ R;
R = FI(R ^ K[6], K[7]) ^ L;
B2 ^= L;
B3 ^= R;
}
store_be(out, B0, B1, B2, B3);
}
/*************************************************
* KASUMI Key Schedule *
*************************************************/
void KASUMI::key(const byte key[], u32bit)
{
static const u16bit RC[] = { 0x0123, 0x4567, 0x89AB, 0xCDEF,
0xFEDC, 0xBA98, 0x7654, 0x3210 };
SecureBuffer<u16bit, 16> K;
for(u32bit j = 0; j != 8; ++j)
{
K[j] = load_be<u16bit>(key, j);
K[j+8] = K[j] ^ RC[j];
}
for(u32bit j = 0; j != 8; ++j)
{
EK[8*j ] = rotate_left(K[(j+0) % 8 ], 2);
EK[8*j+1] = rotate_left(K[(j+2) % 8 + 8], 1);
EK[8*j+2] = rotate_left(K[(j+1) % 8 ], 5);
EK[8*j+3] = K[(j+4) % 8 + 8];
EK[8*j+4] = rotate_left(K[(j+5) % 8 ], 8);
EK[8*j+5] = K[(j+3) % 8 + 8];
EK[8*j+6] = rotate_left(K[(j+6) % 8 ], 13);
EK[8*j+7] = K[(j+7) % 8 + 8];
}
}
}
|
