1 /* $FreeBSD: src/sys/opencrypto/skipjack.c,v 1.3 2005/01/07 02:29:16 imp Exp $ */
2 /* $OpenBSD: skipjack.c,v 1.3 2001/05/05 00:31:34 angelos Exp $ */
4 * Further optimized test implementation of SKIPJACK algorithm
5 * Mark Tillotson <markt@chaos.org.uk>, 25 June 98
6 * Optimizations suit RISC (lots of registers) machine best.
8 * based on unoptimized implementation of
9 * Panu Rissanen <bande@lut.fi> 960624
11 * SKIPJACK and KEA Algorithm Specifications
16 #include <sys/param.h>
18 #include <opencrypto/skipjack.h>
20 static const u_int8_t ftable
[0x100] =
22 0xa3, 0xd7, 0x09, 0x83, 0xf8, 0x48, 0xf6, 0xf4,
23 0xb3, 0x21, 0x15, 0x78, 0x99, 0xb1, 0xaf, 0xf9,
24 0xe7, 0x2d, 0x4d, 0x8a, 0xce, 0x4c, 0xca, 0x2e,
25 0x52, 0x95, 0xd9, 0x1e, 0x4e, 0x38, 0x44, 0x28,
26 0x0a, 0xdf, 0x02, 0xa0, 0x17, 0xf1, 0x60, 0x68,
27 0x12, 0xb7, 0x7a, 0xc3, 0xe9, 0xfa, 0x3d, 0x53,
28 0x96, 0x84, 0x6b, 0xba, 0xf2, 0x63, 0x9a, 0x19,
29 0x7c, 0xae, 0xe5, 0xf5, 0xf7, 0x16, 0x6a, 0xa2,
30 0x39, 0xb6, 0x7b, 0x0f, 0xc1, 0x93, 0x81, 0x1b,
31 0xee, 0xb4, 0x1a, 0xea, 0xd0, 0x91, 0x2f, 0xb8,
32 0x55, 0xb9, 0xda, 0x85, 0x3f, 0x41, 0xbf, 0xe0,
33 0x5a, 0x58, 0x80, 0x5f, 0x66, 0x0b, 0xd8, 0x90,
34 0x35, 0xd5, 0xc0, 0xa7, 0x33, 0x06, 0x65, 0x69,
35 0x45, 0x00, 0x94, 0x56, 0x6d, 0x98, 0x9b, 0x76,
36 0x97, 0xfc, 0xb2, 0xc2, 0xb0, 0xfe, 0xdb, 0x20,
37 0xe1, 0xeb, 0xd6, 0xe4, 0xdd, 0x47, 0x4a, 0x1d,
38 0x42, 0xed, 0x9e, 0x6e, 0x49, 0x3c, 0xcd, 0x43,
39 0x27, 0xd2, 0x07, 0xd4, 0xde, 0xc7, 0x67, 0x18,
40 0x89, 0xcb, 0x30, 0x1f, 0x8d, 0xc6, 0x8f, 0xaa,
41 0xc8, 0x74, 0xdc, 0xc9, 0x5d, 0x5c, 0x31, 0xa4,
42 0x70, 0x88, 0x61, 0x2c, 0x9f, 0x0d, 0x2b, 0x87,
43 0x50, 0x82, 0x54, 0x64, 0x26, 0x7d, 0x03, 0x40,
44 0x34, 0x4b, 0x1c, 0x73, 0xd1, 0xc4, 0xfd, 0x3b,
45 0xcc, 0xfb, 0x7f, 0xab, 0xe6, 0x3e, 0x5b, 0xa5,
46 0xad, 0x04, 0x23, 0x9c, 0x14, 0x51, 0x22, 0xf0,
47 0x29, 0x79, 0x71, 0x7e, 0xff, 0x8c, 0x0e, 0xe2,
48 0x0c, 0xef, 0xbc, 0x72, 0x75, 0x6f, 0x37, 0xa1,
49 0xec, 0xd3, 0x8e, 0x62, 0x8b, 0x86, 0x10, 0xe8,
50 0x08, 0x77, 0x11, 0xbe, 0x92, 0x4f, 0x24, 0xc5,
51 0x32, 0x36, 0x9d, 0xcf, 0xf3, 0xa6, 0xbb, 0xac,
52 0x5e, 0x6c, 0xa9, 0x13, 0x57, 0x25, 0xb5, 0xe3,
53 0xbd, 0xa8, 0x3a, 0x01, 0x05, 0x59, 0x2a, 0x46
57 * For each key byte generate a table to represent the function
58 * ftable [in ^ keybyte]
60 * These tables used to save an XOR in each stage of the G-function
61 * the tables are hopefully pointed to by register allocated variables
66 subkey_table_gen (u_int8_t
*key
, u_int8_t
**key_tables
)
70 for (k
= 0; k
< 10; k
++) {
71 u_int8_t key_byte
= key
[k
];
72 u_int8_t
* table
= key_tables
[k
];
73 for (i
= 0; i
< 0x100; i
++)
74 table
[i
] = ftable
[i
^ key_byte
];
79 #define g(k0, k1, k2, k3, ih, il, oh, ol) \
81 oh = k##k0 [il] ^ ih; \
82 ol = k##k1 [oh] ^ il; \
83 oh = k##k2 [ol] ^ oh; \
84 ol = k##k3 [oh] ^ ol; \
87 #define g0(ih, il, oh, ol) g(0, 1, 2, 3, ih, il, oh, ol)
88 #define g4(ih, il, oh, ol) g(4, 5, 6, 7, ih, il, oh, ol)
89 #define g8(ih, il, oh, ol) g(8, 9, 0, 1, ih, il, oh, ol)
90 #define g2(ih, il, oh, ol) g(2, 3, 4, 5, ih, il, oh, ol)
91 #define g6(ih, il, oh, ol) g(6, 7, 8, 9, ih, il, oh, ol)
94 #define g_inv(k0, k1, k2, k3, ih, il, oh, ol) \
96 ol = k##k3 [ih] ^ il; \
97 oh = k##k2 [ol] ^ ih; \
98 ol = k##k1 [oh] ^ ol; \
99 oh = k##k0 [ol] ^ oh; \
103 #define g0_inv(ih, il, oh, ol) g_inv(0, 1, 2, 3, ih, il, oh, ol)
104 #define g4_inv(ih, il, oh, ol) g_inv(4, 5, 6, 7, ih, il, oh, ol)
105 #define g8_inv(ih, il, oh, ol) g_inv(8, 9, 0, 1, ih, il, oh, ol)
106 #define g2_inv(ih, il, oh, ol) g_inv(2, 3, 4, 5, ih, il, oh, ol)
107 #define g6_inv(ih, il, oh, ol) g_inv(6, 7, 8, 9, ih, il, oh, ol)
109 /* optimized version of Skipjack algorithm
111 * the appropriate g-function is inlined for each round
113 * the data movement is minimized by rotating the names of the
114 * variables w1..w4, not their contents (saves 3 moves per round)
116 * the loops are completely unrolled (needed to staticize choice of g)
118 * compiles to about 470 instructions on a Sparc (gcc -O)
119 * which is about 58 instructions per byte, 14 per round.
120 * gcc seems to leave in some unnecessary and with 0xFF operations
121 * but only in the latter part of the functions. Perhaps it
122 * runs out of resources to properly optimize long inlined function?
123 * in theory should get about 11 instructions per round, not 14
127 skipjack_forwards(u_int8_t
*plain
, u_int8_t
*cipher
, u_int8_t
**key_tables
)
129 u_int8_t wh1
= plain
[0]; u_int8_t wl1
= plain
[1];
130 u_int8_t wh2
= plain
[2]; u_int8_t wl2
= plain
[3];
131 u_int8_t wh3
= plain
[4]; u_int8_t wl3
= plain
[5];
132 u_int8_t wh4
= plain
[6]; u_int8_t wl4
= plain
[7];
134 u_int8_t
* k0
= key_tables
[0];
135 u_int8_t
* k1
= key_tables
[1];
136 u_int8_t
* k2
= key_tables
[2];
137 u_int8_t
* k3
= key_tables
[3];
138 u_int8_t
* k4
= key_tables
[4];
139 u_int8_t
* k5
= key_tables
[5];
140 u_int8_t
* k6
= key_tables
[6];
141 u_int8_t
* k7
= key_tables
[7];
142 u_int8_t
* k8
= key_tables
[8];
143 u_int8_t
* k9
= key_tables
[9];
146 g0 (wh1
,wl1
, wh1
,wl1
); wl4
^= wl1
^ 1; wh4
^= wh1
;
147 g4 (wh4
,wl4
, wh4
,wl4
); wl3
^= wl4
^ 2; wh3
^= wh4
;
148 g8 (wh3
,wl3
, wh3
,wl3
); wl2
^= wl3
^ 3; wh2
^= wh3
;
149 g2 (wh2
,wl2
, wh2
,wl2
); wl1
^= wl2
^ 4; wh1
^= wh2
;
150 g6 (wh1
,wl1
, wh1
,wl1
); wl4
^= wl1
^ 5; wh4
^= wh1
;
151 g0 (wh4
,wl4
, wh4
,wl4
); wl3
^= wl4
^ 6; wh3
^= wh4
;
152 g4 (wh3
,wl3
, wh3
,wl3
); wl2
^= wl3
^ 7; wh2
^= wh3
;
153 g8 (wh2
,wl2
, wh2
,wl2
); wl1
^= wl2
^ 8; wh1
^= wh2
;
155 /* second 8 rounds */
156 wh2
^= wh1
; wl2
^= wl1
^ 9 ; g2 (wh1
,wl1
, wh1
,wl1
);
157 wh1
^= wh4
; wl1
^= wl4
^ 10; g6 (wh4
,wl4
, wh4
,wl4
);
158 wh4
^= wh3
; wl4
^= wl3
^ 11; g0 (wh3
,wl3
, wh3
,wl3
);
159 wh3
^= wh2
; wl3
^= wl2
^ 12; g4 (wh2
,wl2
, wh2
,wl2
);
160 wh2
^= wh1
; wl2
^= wl1
^ 13; g8 (wh1
,wl1
, wh1
,wl1
);
161 wh1
^= wh4
; wl1
^= wl4
^ 14; g2 (wh4
,wl4
, wh4
,wl4
);
162 wh4
^= wh3
; wl4
^= wl3
^ 15; g6 (wh3
,wl3
, wh3
,wl3
);
163 wh3
^= wh2
; wl3
^= wl2
^ 16; g0 (wh2
,wl2
, wh2
,wl2
);
166 g4 (wh1
,wl1
, wh1
,wl1
); wl4
^= wl1
^ 17; wh4
^= wh1
;
167 g8 (wh4
,wl4
, wh4
,wl4
); wl3
^= wl4
^ 18; wh3
^= wh4
;
168 g2 (wh3
,wl3
, wh3
,wl3
); wl2
^= wl3
^ 19; wh2
^= wh3
;
169 g6 (wh2
,wl2
, wh2
,wl2
); wl1
^= wl2
^ 20; wh1
^= wh2
;
170 g0 (wh1
,wl1
, wh1
,wl1
); wl4
^= wl1
^ 21; wh4
^= wh1
;
171 g4 (wh4
,wl4
, wh4
,wl4
); wl3
^= wl4
^ 22; wh3
^= wh4
;
172 g8 (wh3
,wl3
, wh3
,wl3
); wl2
^= wl3
^ 23; wh2
^= wh3
;
173 g2 (wh2
,wl2
, wh2
,wl2
); wl1
^= wl2
^ 24; wh1
^= wh2
;
176 wh2
^= wh1
; wl2
^= wl1
^ 25; g6 (wh1
,wl1
, wh1
,wl1
);
177 wh1
^= wh4
; wl1
^= wl4
^ 26; g0 (wh4
,wl4
, wh4
,wl4
);
178 wh4
^= wh3
; wl4
^= wl3
^ 27; g4 (wh3
,wl3
, wh3
,wl3
);
179 wh3
^= wh2
; wl3
^= wl2
^ 28; g8 (wh2
,wl2
, wh2
,wl2
);
180 wh2
^= wh1
; wl2
^= wl1
^ 29; g2 (wh1
,wl1
, wh1
,wl1
);
181 wh1
^= wh4
; wl1
^= wl4
^ 30; g6 (wh4
,wl4
, wh4
,wl4
);
182 wh4
^= wh3
; wl4
^= wl3
^ 31; g0 (wh3
,wl3
, wh3
,wl3
);
183 wh3
^= wh2
; wl3
^= wl2
^ 32; g4 (wh2
,wl2
, wh2
,wl2
);
185 /* pack into byte vector */
186 cipher
[0] = wh1
; cipher
[1] = wl1
;
187 cipher
[2] = wh2
; cipher
[3] = wl2
;
188 cipher
[4] = wh3
; cipher
[5] = wl3
;
189 cipher
[6] = wh4
; cipher
[7] = wl4
;
194 skipjack_backwards (u_int8_t
*cipher
, u_int8_t
*plain
, u_int8_t
**key_tables
)
196 /* setup 4 16-bit portions */
197 u_int8_t wh1
= cipher
[0]; u_int8_t wl1
= cipher
[1];
198 u_int8_t wh2
= cipher
[2]; u_int8_t wl2
= cipher
[3];
199 u_int8_t wh3
= cipher
[4]; u_int8_t wl3
= cipher
[5];
200 u_int8_t wh4
= cipher
[6]; u_int8_t wl4
= cipher
[7];
202 u_int8_t
* k0
= key_tables
[0];
203 u_int8_t
* k1
= key_tables
[1];
204 u_int8_t
* k2
= key_tables
[2];
205 u_int8_t
* k3
= key_tables
[3];
206 u_int8_t
* k4
= key_tables
[4];
207 u_int8_t
* k5
= key_tables
[5];
208 u_int8_t
* k6
= key_tables
[6];
209 u_int8_t
* k7
= key_tables
[7];
210 u_int8_t
* k8
= key_tables
[8];
211 u_int8_t
* k9
= key_tables
[9];
214 g4_inv (wh2
,wl2
, wh2
,wl2
); wl3
^= wl2
^ 32; wh3
^= wh2
;
215 g0_inv (wh3
,wl3
, wh3
,wl3
); wl4
^= wl3
^ 31; wh4
^= wh3
;
216 g6_inv (wh4
,wl4
, wh4
,wl4
); wl1
^= wl4
^ 30; wh1
^= wh4
;
217 g2_inv (wh1
,wl1
, wh1
,wl1
); wl2
^= wl1
^ 29; wh2
^= wh1
;
218 g8_inv (wh2
,wl2
, wh2
,wl2
); wl3
^= wl2
^ 28; wh3
^= wh2
;
219 g4_inv (wh3
,wl3
, wh3
,wl3
); wl4
^= wl3
^ 27; wh4
^= wh3
;
220 g0_inv (wh4
,wl4
, wh4
,wl4
); wl1
^= wl4
^ 26; wh1
^= wh4
;
221 g6_inv (wh1
,wl1
, wh1
,wl1
); wl2
^= wl1
^ 25; wh2
^= wh1
;
223 /* second 8 rounds */
224 wh1
^= wh2
; wl1
^= wl2
^ 24; g2_inv (wh2
,wl2
, wh2
,wl2
);
225 wh2
^= wh3
; wl2
^= wl3
^ 23; g8_inv (wh3
,wl3
, wh3
,wl3
);
226 wh3
^= wh4
; wl3
^= wl4
^ 22; g4_inv (wh4
,wl4
, wh4
,wl4
);
227 wh4
^= wh1
; wl4
^= wl1
^ 21; g0_inv (wh1
,wl1
, wh1
,wl1
);
228 wh1
^= wh2
; wl1
^= wl2
^ 20; g6_inv (wh2
,wl2
, wh2
,wl2
);
229 wh2
^= wh3
; wl2
^= wl3
^ 19; g2_inv (wh3
,wl3
, wh3
,wl3
);
230 wh3
^= wh4
; wl3
^= wl4
^ 18; g8_inv (wh4
,wl4
, wh4
,wl4
);
231 wh4
^= wh1
; wl4
^= wl1
^ 17; g4_inv (wh1
,wl1
, wh1
,wl1
);
234 g0_inv (wh2
,wl2
, wh2
,wl2
); wl3
^= wl2
^ 16; wh3
^= wh2
;
235 g6_inv (wh3
,wl3
, wh3
,wl3
); wl4
^= wl3
^ 15; wh4
^= wh3
;
236 g2_inv (wh4
,wl4
, wh4
,wl4
); wl1
^= wl4
^ 14; wh1
^= wh4
;
237 g8_inv (wh1
,wl1
, wh1
,wl1
); wl2
^= wl1
^ 13; wh2
^= wh1
;
238 g4_inv (wh2
,wl2
, wh2
,wl2
); wl3
^= wl2
^ 12; wh3
^= wh2
;
239 g0_inv (wh3
,wl3
, wh3
,wl3
); wl4
^= wl3
^ 11; wh4
^= wh3
;
240 g6_inv (wh4
,wl4
, wh4
,wl4
); wl1
^= wl4
^ 10; wh1
^= wh4
;
241 g2_inv (wh1
,wl1
, wh1
,wl1
); wl2
^= wl1
^ 9; wh2
^= wh1
;
244 wh1
^= wh2
; wl1
^= wl2
^ 8; g8_inv (wh2
,wl2
, wh2
,wl2
);
245 wh2
^= wh3
; wl2
^= wl3
^ 7; g4_inv (wh3
,wl3
, wh3
,wl3
);
246 wh3
^= wh4
; wl3
^= wl4
^ 6; g0_inv (wh4
,wl4
, wh4
,wl4
);
247 wh4
^= wh1
; wl4
^= wl1
^ 5; g6_inv (wh1
,wl1
, wh1
,wl1
);
248 wh1
^= wh2
; wl1
^= wl2
^ 4; g2_inv (wh2
,wl2
, wh2
,wl2
);
249 wh2
^= wh3
; wl2
^= wl3
^ 3; g8_inv (wh3
,wl3
, wh3
,wl3
);
250 wh3
^= wh4
; wl3
^= wl4
^ 2; g4_inv (wh4
,wl4
, wh4
,wl4
);
251 wh4
^= wh1
; wl4
^= wl1
^ 1; g0_inv (wh1
,wl1
, wh1
,wl1
);
253 /* pack into byte vector */
254 plain
[0] = wh1
; plain
[1] = wl1
;
255 plain
[2] = wh2
; plain
[3] = wl2
;
256 plain
[4] = wh3
; plain
[5] = wl3
;
257 plain
[6] = wh4
; plain
[7] = wl4
;