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
|
// skipjack.cpp - modified by Wei Dai from Paulo Barreto's skipjack32.c,
// which is public domain according to his web site.
#include "pch.h"
#ifndef CRYPTOPP_IMPORTS
#include "skipjack.h"
/*
* Optimized implementation of SKIPJACK algorithm
*
* originally written by Panu Rissanen <bande@lut.fi> 1998.06.24
* optimized by Mark Tillotson <markt@chaos.org.uk> 1998.06.25
* optimized by Paulo Barreto <pbarreto@nw.com.br> 1998.06.30
*/
NAMESPACE_BEGIN(CryptoPP)
/**
* The F-table byte permutation (see description of the G-box permutation)
*/
const byte SKIPJACK::Base::fTable[256] = {
0xa3,0xd7,0x09,0x83,0xf8,0x48,0xf6,0xf4,0xb3,0x21,0x15,0x78,0x99,0xb1,0xaf,0xf9,
0xe7,0x2d,0x4d,0x8a,0xce,0x4c,0xca,0x2e,0x52,0x95,0xd9,0x1e,0x4e,0x38,0x44,0x28,
0x0a,0xdf,0x02,0xa0,0x17,0xf1,0x60,0x68,0x12,0xb7,0x7a,0xc3,0xe9,0xfa,0x3d,0x53,
0x96,0x84,0x6b,0xba,0xf2,0x63,0x9a,0x19,0x7c,0xae,0xe5,0xf5,0xf7,0x16,0x6a,0xa2,
0x39,0xb6,0x7b,0x0f,0xc1,0x93,0x81,0x1b,0xee,0xb4,0x1a,0xea,0xd0,0x91,0x2f,0xb8,
0x55,0xb9,0xda,0x85,0x3f,0x41,0xbf,0xe0,0x5a,0x58,0x80,0x5f,0x66,0x0b,0xd8,0x90,
0x35,0xd5,0xc0,0xa7,0x33,0x06,0x65,0x69,0x45,0x00,0x94,0x56,0x6d,0x98,0x9b,0x76,
0x97,0xfc,0xb2,0xc2,0xb0,0xfe,0xdb,0x20,0xe1,0xeb,0xd6,0xe4,0xdd,0x47,0x4a,0x1d,
0x42,0xed,0x9e,0x6e,0x49,0x3c,0xcd,0x43,0x27,0xd2,0x07,0xd4,0xde,0xc7,0x67,0x18,
0x89,0xcb,0x30,0x1f,0x8d,0xc6,0x8f,0xaa,0xc8,0x74,0xdc,0xc9,0x5d,0x5c,0x31,0xa4,
0x70,0x88,0x61,0x2c,0x9f,0x0d,0x2b,0x87,0x50,0x82,0x54,0x64,0x26,0x7d,0x03,0x40,
0x34,0x4b,0x1c,0x73,0xd1,0xc4,0xfd,0x3b,0xcc,0xfb,0x7f,0xab,0xe6,0x3e,0x5b,0xa5,
0xad,0x04,0x23,0x9c,0x14,0x51,0x22,0xf0,0x29,0x79,0x71,0x7e,0xff,0x8c,0x0e,0xe2,
0x0c,0xef,0xbc,0x72,0x75,0x6f,0x37,0xa1,0xec,0xd3,0x8e,0x62,0x8b,0x86,0x10,0xe8,
0x08,0x77,0x11,0xbe,0x92,0x4f,0x24,0xc5,0x32,0x36,0x9d,0xcf,0xf3,0xa6,0xbb,0xac,
0x5e,0x6c,0xa9,0x13,0x57,0x25,0xb5,0xe3,0xbd,0xa8,0x3a,0x01,0x05,0x59,0x2a,0x46
};
/**
* The key-dependent permutation G on V^16 is a four-round Feistel network.
* The round function is a fixed byte-substitution table (permutation on V^8),
* the F-table. Each round of G incorporates a single byte from the key.
*/
#define g(tab, w, i, j, k, l) \
{ \
w ^= (word)tab[i][w & 0xff] << 8; \
w ^= (word)tab[j][w >> 8]; \
w ^= (word)tab[k][w & 0xff] << 8; \
w ^= (word)tab[l][w >> 8]; \
}
#define g0(tab, w) g(tab, w, 0, 1, 2, 3)
#define g1(tab, w) g(tab, w, 4, 5, 6, 7)
#define g2(tab, w) g(tab, w, 8, 9, 0, 1)
#define g3(tab, w) g(tab, w, 2, 3, 4, 5)
#define g4(tab, w) g(tab, w, 6, 7, 8, 9)
/**
* The inverse of the G permutation.
*/
#define h(tab, w, i, j, k, l) \
{ \
w ^= (word)tab[l][w >> 8]; \
w ^= (word)tab[k][w & 0xff] << 8; \
w ^= (word)tab[j][w >> 8]; \
w ^= (word)tab[i][w & 0xff] << 8; \
}
#define h0(tab, w) h(tab, w, 0, 1, 2, 3)
#define h1(tab, w) h(tab, w, 4, 5, 6, 7)
#define h2(tab, w) h(tab, w, 8, 9, 0, 1)
#define h3(tab, w) h(tab, w, 2, 3, 4, 5)
#define h4(tab, w) h(tab, w, 6, 7, 8, 9)
/**
* Preprocess a user key into a table to save an XOR at each F-table access.
*/
void SKIPJACK::Base::UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &)
{
AssertValidKeyLength(length);
/* tab[i][c] = fTable[c ^ key[i]] */
int i;
for (i = 0; i < 10; i++) {
byte *t = tab[i], k = key[9-i];
int c;
for (c = 0; c < 256; c++) {
t[c] = fTable[c ^ k];
}
}
}
typedef BlockGetAndPut<word16, LittleEndian> Block;
/**
* Encrypt a single block of data.
*/
void SKIPJACK::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word w1, w2, w3, w4;
Block::Get(inBlock)(w4)(w3)(w2)(w1);
/* stepping rule A: */
g0(tab, w1); w4 ^= w1 ^ 1;
g1(tab, w4); w3 ^= w4 ^ 2;
g2(tab, w3); w2 ^= w3 ^ 3;
g3(tab, w2); w1 ^= w2 ^ 4;
g4(tab, w1); w4 ^= w1 ^ 5;
g0(tab, w4); w3 ^= w4 ^ 6;
g1(tab, w3); w2 ^= w3 ^ 7;
g2(tab, w2); w1 ^= w2 ^ 8;
/* stepping rule B: */
w2 ^= w1 ^ 9; g3(tab, w1);
w1 ^= w4 ^ 10; g4(tab, w4);
w4 ^= w3 ^ 11; g0(tab, w3);
w3 ^= w2 ^ 12; g1(tab, w2);
w2 ^= w1 ^ 13; g2(tab, w1);
w1 ^= w4 ^ 14; g3(tab, w4);
w4 ^= w3 ^ 15; g4(tab, w3);
w3 ^= w2 ^ 16; g0(tab, w2);
/* stepping rule A: */
g1(tab, w1); w4 ^= w1 ^ 17;
g2(tab, w4); w3 ^= w4 ^ 18;
g3(tab, w3); w2 ^= w3 ^ 19;
g4(tab, w2); w1 ^= w2 ^ 20;
g0(tab, w1); w4 ^= w1 ^ 21;
g1(tab, w4); w3 ^= w4 ^ 22;
g2(tab, w3); w2 ^= w3 ^ 23;
g3(tab, w2); w1 ^= w2 ^ 24;
/* stepping rule B: */
w2 ^= w1 ^ 25; g4(tab, w1);
w1 ^= w4 ^ 26; g0(tab, w4);
w4 ^= w3 ^ 27; g1(tab, w3);
w3 ^= w2 ^ 28; g2(tab, w2);
w2 ^= w1 ^ 29; g3(tab, w1);
w1 ^= w4 ^ 30; g4(tab, w4);
w4 ^= w3 ^ 31; g0(tab, w3);
w3 ^= w2 ^ 32; g1(tab, w2);
Block::Put(xorBlock, outBlock)(w4)(w3)(w2)(w1);
}
/**
* Decrypt a single block of data.
*/
void SKIPJACK::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word w1, w2, w3, w4;
Block::Get(inBlock)(w4)(w3)(w2)(w1);
/* stepping rule A: */
h1(tab, w2); w3 ^= w2 ^ 32;
h0(tab, w3); w4 ^= w3 ^ 31;
h4(tab, w4); w1 ^= w4 ^ 30;
h3(tab, w1); w2 ^= w1 ^ 29;
h2(tab, w2); w3 ^= w2 ^ 28;
h1(tab, w3); w4 ^= w3 ^ 27;
h0(tab, w4); w1 ^= w4 ^ 26;
h4(tab, w1); w2 ^= w1 ^ 25;
/* stepping rule B: */
w1 ^= w2 ^ 24; h3(tab, w2);
w2 ^= w3 ^ 23; h2(tab, w3);
w3 ^= w4 ^ 22; h1(tab, w4);
w4 ^= w1 ^ 21; h0(tab, w1);
w1 ^= w2 ^ 20; h4(tab, w2);
w2 ^= w3 ^ 19; h3(tab, w3);
w3 ^= w4 ^ 18; h2(tab, w4);
w4 ^= w1 ^ 17; h1(tab, w1);
/* stepping rule A: */
h0(tab, w2); w3 ^= w2 ^ 16;
h4(tab, w3); w4 ^= w3 ^ 15;
h3(tab, w4); w1 ^= w4 ^ 14;
h2(tab, w1); w2 ^= w1 ^ 13;
h1(tab, w2); w3 ^= w2 ^ 12;
h0(tab, w3); w4 ^= w3 ^ 11;
h4(tab, w4); w1 ^= w4 ^ 10;
h3(tab, w1); w2 ^= w1 ^ 9;
/* stepping rule B: */
w1 ^= w2 ^ 8; h2(tab, w2);
w2 ^= w3 ^ 7; h1(tab, w3);
w3 ^= w4 ^ 6; h0(tab, w4);
w4 ^= w1 ^ 5; h4(tab, w1);
w1 ^= w2 ^ 4; h3(tab, w2);
w2 ^= w3 ^ 3; h2(tab, w3);
w3 ^= w4 ^ 2; h1(tab, w4);
w4 ^= w1 ^ 1; h0(tab, w1);
Block::Put(xorBlock, outBlock)(w4)(w3)(w2)(w1);
}
NAMESPACE_END
#endif
|
