| 1 | /* $FreeBSD: src/sys/opencrypto/skipjack.c,v 1.1.2.1 2002/11/21 23:34:23 sam Exp $ */ |
| 2 | /* $DragonFly: src/sys/opencrypto/skipjack.c,v 1.2 2003/06/17 04:28:54 dillon Exp $ */ |
| 3 | /* $OpenBSD: skipjack.c,v 1.3 2001/05/05 00:31:34 angelos Exp $ */ |
| 4 | |
| 5 | /* |
| 6 | * Further optimized test implementation of SKIPJACK algorithm |
| 7 | * Mark Tillotson <markt@chaos.org.uk>, 25 June 98 |
| 8 | * Optimizations suit RISC (lots of registers) machine best. |
| 9 | * |
| 10 | * based on unoptimized implementation of |
| 11 | * Panu Rissanen <bande@lut.fi> 960624 |
| 12 | * |
| 13 | * SKIPJACK and KEA Algorithm Specifications |
| 14 | * Version 2.0 |
| 15 | * 29 May 1998 |
| 16 | */ |
| 17 | |
| 18 | #include <sys/param.h> |
| 19 | |
| 20 | #include <opencrypto/skipjack.h> |
| 21 | |
| 22 | static const u_int8_t ftable[0x100] = |
| 23 | { |
| 24 | 0xa3, 0xd7, 0x09, 0x83, 0xf8, 0x48, 0xf6, 0xf4, |
| 25 | 0xb3, 0x21, 0x15, 0x78, 0x99, 0xb1, 0xaf, 0xf9, |
| 26 | 0xe7, 0x2d, 0x4d, 0x8a, 0xce, 0x4c, 0xca, 0x2e, |
| 27 | 0x52, 0x95, 0xd9, 0x1e, 0x4e, 0x38, 0x44, 0x28, |
| 28 | 0x0a, 0xdf, 0x02, 0xa0, 0x17, 0xf1, 0x60, 0x68, |
| 29 | 0x12, 0xb7, 0x7a, 0xc3, 0xe9, 0xfa, 0x3d, 0x53, |
| 30 | 0x96, 0x84, 0x6b, 0xba, 0xf2, 0x63, 0x9a, 0x19, |
| 31 | 0x7c, 0xae, 0xe5, 0xf5, 0xf7, 0x16, 0x6a, 0xa2, |
| 32 | 0x39, 0xb6, 0x7b, 0x0f, 0xc1, 0x93, 0x81, 0x1b, |
| 33 | 0xee, 0xb4, 0x1a, 0xea, 0xd0, 0x91, 0x2f, 0xb8, |
| 34 | 0x55, 0xb9, 0xda, 0x85, 0x3f, 0x41, 0xbf, 0xe0, |
| 35 | 0x5a, 0x58, 0x80, 0x5f, 0x66, 0x0b, 0xd8, 0x90, |
| 36 | 0x35, 0xd5, 0xc0, 0xa7, 0x33, 0x06, 0x65, 0x69, |
| 37 | 0x45, 0x00, 0x94, 0x56, 0x6d, 0x98, 0x9b, 0x76, |
| 38 | 0x97, 0xfc, 0xb2, 0xc2, 0xb0, 0xfe, 0xdb, 0x20, |
| 39 | 0xe1, 0xeb, 0xd6, 0xe4, 0xdd, 0x47, 0x4a, 0x1d, |
| 40 | 0x42, 0xed, 0x9e, 0x6e, 0x49, 0x3c, 0xcd, 0x43, |
| 41 | 0x27, 0xd2, 0x07, 0xd4, 0xde, 0xc7, 0x67, 0x18, |
| 42 | 0x89, 0xcb, 0x30, 0x1f, 0x8d, 0xc6, 0x8f, 0xaa, |
| 43 | 0xc8, 0x74, 0xdc, 0xc9, 0x5d, 0x5c, 0x31, 0xa4, |
| 44 | 0x70, 0x88, 0x61, 0x2c, 0x9f, 0x0d, 0x2b, 0x87, |
| 45 | 0x50, 0x82, 0x54, 0x64, 0x26, 0x7d, 0x03, 0x40, |
| 46 | 0x34, 0x4b, 0x1c, 0x73, 0xd1, 0xc4, 0xfd, 0x3b, |
| 47 | 0xcc, 0xfb, 0x7f, 0xab, 0xe6, 0x3e, 0x5b, 0xa5, |
| 48 | 0xad, 0x04, 0x23, 0x9c, 0x14, 0x51, 0x22, 0xf0, |
| 49 | 0x29, 0x79, 0x71, 0x7e, 0xff, 0x8c, 0x0e, 0xe2, |
| 50 | 0x0c, 0xef, 0xbc, 0x72, 0x75, 0x6f, 0x37, 0xa1, |
| 51 | 0xec, 0xd3, 0x8e, 0x62, 0x8b, 0x86, 0x10, 0xe8, |
| 52 | 0x08, 0x77, 0x11, 0xbe, 0x92, 0x4f, 0x24, 0xc5, |
| 53 | 0x32, 0x36, 0x9d, 0xcf, 0xf3, 0xa6, 0xbb, 0xac, |
| 54 | 0x5e, 0x6c, 0xa9, 0x13, 0x57, 0x25, 0xb5, 0xe3, |
| 55 | 0xbd, 0xa8, 0x3a, 0x01, 0x05, 0x59, 0x2a, 0x46 |
| 56 | }; |
| 57 | |
| 58 | /* |
| 59 | * For each key byte generate a table to represent the function |
| 60 | * ftable [in ^ keybyte] |
| 61 | * |
| 62 | * These tables used to save an XOR in each stage of the G-function |
| 63 | * the tables are hopefully pointed to by register allocated variables |
| 64 | * k0, k1..k9 |
| 65 | */ |
| 66 | void |
| 67 | subkey_table_gen (u_int8_t *key, u_int8_t **key_tables) |
| 68 | { |
| 69 | int i, k; |
| 70 | |
| 71 | for (k = 0; k < 10; k++) { |
| 72 | u_int8_t key_byte = key [k]; |
| 73 | u_int8_t * table = key_tables[k]; |
| 74 | for (i = 0; i < 0x100; i++) |
| 75 | table [i] = ftable [i ^ key_byte]; |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | |
| 80 | #define g(k0, k1, k2, k3, ih, il, oh, ol) \ |
| 81 | { \ |
| 82 | oh = k##k0 [il] ^ ih; \ |
| 83 | ol = k##k1 [oh] ^ il; \ |
| 84 | oh = k##k2 [ol] ^ oh; \ |
| 85 | ol = k##k3 [oh] ^ ol; \ |
| 86 | } |
| 87 | |
| 88 | #define g0(ih, il, oh, ol) g(0, 1, 2, 3, ih, il, oh, ol) |
| 89 | #define g4(ih, il, oh, ol) g(4, 5, 6, 7, ih, il, oh, ol) |
| 90 | #define g8(ih, il, oh, ol) g(8, 9, 0, 1, ih, il, oh, ol) |
| 91 | #define g2(ih, il, oh, ol) g(2, 3, 4, 5, ih, il, oh, ol) |
| 92 | #define g6(ih, il, oh, ol) g(6, 7, 8, 9, ih, il, oh, ol) |
| 93 | |
| 94 | |
| 95 | #define g_inv(k0, k1, k2, k3, ih, il, oh, ol) \ |
| 96 | { \ |
| 97 | ol = k##k3 [ih] ^ il; \ |
| 98 | oh = k##k2 [ol] ^ ih; \ |
| 99 | ol = k##k1 [oh] ^ ol; \ |
| 100 | oh = k##k0 [ol] ^ oh; \ |
| 101 | } |
| 102 | |
| 103 | |
| 104 | #define g0_inv(ih, il, oh, ol) g_inv(0, 1, 2, 3, ih, il, oh, ol) |
| 105 | #define g4_inv(ih, il, oh, ol) g_inv(4, 5, 6, 7, ih, il, oh, ol) |
| 106 | #define g8_inv(ih, il, oh, ol) g_inv(8, 9, 0, 1, ih, il, oh, ol) |
| 107 | #define g2_inv(ih, il, oh, ol) g_inv(2, 3, 4, 5, ih, il, oh, ol) |
| 108 | #define g6_inv(ih, il, oh, ol) g_inv(6, 7, 8, 9, ih, il, oh, ol) |
| 109 | |
| 110 | /* optimized version of Skipjack algorithm |
| 111 | * |
| 112 | * the appropriate g-function is inlined for each round |
| 113 | * |
| 114 | * the data movement is minimized by rotating the names of the |
| 115 | * variables w1..w4, not their contents (saves 3 moves per round) |
| 116 | * |
| 117 | * the loops are completely unrolled (needed to staticize choice of g) |
| 118 | * |
| 119 | * compiles to about 470 instructions on a Sparc (gcc -O) |
| 120 | * which is about 58 instructions per byte, 14 per round. |
| 121 | * gcc seems to leave in some unnecessary and with 0xFF operations |
| 122 | * but only in the latter part of the functions. Perhaps it |
| 123 | * runs out of resources to properly optimize long inlined function? |
| 124 | * in theory should get about 11 instructions per round, not 14 |
| 125 | */ |
| 126 | |
| 127 | void |
| 128 | skipjack_forwards(u_int8_t *plain, u_int8_t *cipher, u_int8_t **key_tables) |
| 129 | { |
| 130 | u_int8_t wh1 = plain[0]; u_int8_t wl1 = plain[1]; |
| 131 | u_int8_t wh2 = plain[2]; u_int8_t wl2 = plain[3]; |
| 132 | u_int8_t wh3 = plain[4]; u_int8_t wl3 = plain[5]; |
| 133 | u_int8_t wh4 = plain[6]; u_int8_t wl4 = plain[7]; |
| 134 | |
| 135 | u_int8_t * k0 = key_tables [0]; |
| 136 | u_int8_t * k1 = key_tables [1]; |
| 137 | u_int8_t * k2 = key_tables [2]; |
| 138 | u_int8_t * k3 = key_tables [3]; |
| 139 | u_int8_t * k4 = key_tables [4]; |
| 140 | u_int8_t * k5 = key_tables [5]; |
| 141 | u_int8_t * k6 = key_tables [6]; |
| 142 | u_int8_t * k7 = key_tables [7]; |
| 143 | u_int8_t * k8 = key_tables [8]; |
| 144 | u_int8_t * k9 = key_tables [9]; |
| 145 | |
| 146 | /* first 8 rounds */ |
| 147 | g0 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 1; wh4 ^= wh1; |
| 148 | g4 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 2; wh3 ^= wh4; |
| 149 | g8 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 3; wh2 ^= wh3; |
| 150 | g2 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 4; wh1 ^= wh2; |
| 151 | g6 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 5; wh4 ^= wh1; |
| 152 | g0 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 6; wh3 ^= wh4; |
| 153 | g4 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 7; wh2 ^= wh3; |
| 154 | g8 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 8; wh1 ^= wh2; |
| 155 | |
| 156 | /* second 8 rounds */ |
| 157 | wh2 ^= wh1; wl2 ^= wl1 ^ 9 ; g2 (wh1,wl1, wh1,wl1); |
| 158 | wh1 ^= wh4; wl1 ^= wl4 ^ 10; g6 (wh4,wl4, wh4,wl4); |
| 159 | wh4 ^= wh3; wl4 ^= wl3 ^ 11; g0 (wh3,wl3, wh3,wl3); |
| 160 | wh3 ^= wh2; wl3 ^= wl2 ^ 12; g4 (wh2,wl2, wh2,wl2); |
| 161 | wh2 ^= wh1; wl2 ^= wl1 ^ 13; g8 (wh1,wl1, wh1,wl1); |
| 162 | wh1 ^= wh4; wl1 ^= wl4 ^ 14; g2 (wh4,wl4, wh4,wl4); |
| 163 | wh4 ^= wh3; wl4 ^= wl3 ^ 15; g6 (wh3,wl3, wh3,wl3); |
| 164 | wh3 ^= wh2; wl3 ^= wl2 ^ 16; g0 (wh2,wl2, wh2,wl2); |
| 165 | |
| 166 | /* third 8 rounds */ |
| 167 | g4 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 17; wh4 ^= wh1; |
| 168 | g8 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 18; wh3 ^= wh4; |
| 169 | g2 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 19; wh2 ^= wh3; |
| 170 | g6 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 20; wh1 ^= wh2; |
| 171 | g0 (wh1,wl1, wh1,wl1); wl4 ^= wl1 ^ 21; wh4 ^= wh1; |
| 172 | g4 (wh4,wl4, wh4,wl4); wl3 ^= wl4 ^ 22; wh3 ^= wh4; |
| 173 | g8 (wh3,wl3, wh3,wl3); wl2 ^= wl3 ^ 23; wh2 ^= wh3; |
| 174 | g2 (wh2,wl2, wh2,wl2); wl1 ^= wl2 ^ 24; wh1 ^= wh2; |
| 175 | |
| 176 | /* last 8 rounds */ |
| 177 | wh2 ^= wh1; wl2 ^= wl1 ^ 25; g6 (wh1,wl1, wh1,wl1); |
| 178 | wh1 ^= wh4; wl1 ^= wl4 ^ 26; g0 (wh4,wl4, wh4,wl4); |
| 179 | wh4 ^= wh3; wl4 ^= wl3 ^ 27; g4 (wh3,wl3, wh3,wl3); |
| 180 | wh3 ^= wh2; wl3 ^= wl2 ^ 28; g8 (wh2,wl2, wh2,wl2); |
| 181 | wh2 ^= wh1; wl2 ^= wl1 ^ 29; g2 (wh1,wl1, wh1,wl1); |
| 182 | wh1 ^= wh4; wl1 ^= wl4 ^ 30; g6 (wh4,wl4, wh4,wl4); |
| 183 | wh4 ^= wh3; wl4 ^= wl3 ^ 31; g0 (wh3,wl3, wh3,wl3); |
| 184 | wh3 ^= wh2; wl3 ^= wl2 ^ 32; g4 (wh2,wl2, wh2,wl2); |
| 185 | |
| 186 | /* pack into byte vector */ |
| 187 | cipher [0] = wh1; cipher [1] = wl1; |
| 188 | cipher [2] = wh2; cipher [3] = wl2; |
| 189 | cipher [4] = wh3; cipher [5] = wl3; |
| 190 | cipher [6] = wh4; cipher [7] = wl4; |
| 191 | } |
| 192 | |
| 193 | |
| 194 | void |
| 195 | skipjack_backwards (u_int8_t *cipher, u_int8_t *plain, u_int8_t **key_tables) |
| 196 | { |
| 197 | /* setup 4 16-bit portions */ |
| 198 | u_int8_t wh1 = cipher[0]; u_int8_t wl1 = cipher[1]; |
| 199 | u_int8_t wh2 = cipher[2]; u_int8_t wl2 = cipher[3]; |
| 200 | u_int8_t wh3 = cipher[4]; u_int8_t wl3 = cipher[5]; |
| 201 | u_int8_t wh4 = cipher[6]; u_int8_t wl4 = cipher[7]; |
| 202 | |
| 203 | u_int8_t * k0 = key_tables [0]; |
| 204 | u_int8_t * k1 = key_tables [1]; |
| 205 | u_int8_t * k2 = key_tables [2]; |
| 206 | u_int8_t * k3 = key_tables [3]; |
| 207 | u_int8_t * k4 = key_tables [4]; |
| 208 | u_int8_t * k5 = key_tables [5]; |
| 209 | u_int8_t * k6 = key_tables [6]; |
| 210 | u_int8_t * k7 = key_tables [7]; |
| 211 | u_int8_t * k8 = key_tables [8]; |
| 212 | u_int8_t * k9 = key_tables [9]; |
| 213 | |
| 214 | /* first 8 rounds */ |
| 215 | g4_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 32; wh3 ^= wh2; |
| 216 | g0_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 31; wh4 ^= wh3; |
| 217 | g6_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 30; wh1 ^= wh4; |
| 218 | g2_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 29; wh2 ^= wh1; |
| 219 | g8_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 28; wh3 ^= wh2; |
| 220 | g4_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 27; wh4 ^= wh3; |
| 221 | g0_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 26; wh1 ^= wh4; |
| 222 | g6_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 25; wh2 ^= wh1; |
| 223 | |
| 224 | /* second 8 rounds */ |
| 225 | wh1 ^= wh2; wl1 ^= wl2 ^ 24; g2_inv (wh2,wl2, wh2,wl2); |
| 226 | wh2 ^= wh3; wl2 ^= wl3 ^ 23; g8_inv (wh3,wl3, wh3,wl3); |
| 227 | wh3 ^= wh4; wl3 ^= wl4 ^ 22; g4_inv (wh4,wl4, wh4,wl4); |
| 228 | wh4 ^= wh1; wl4 ^= wl1 ^ 21; g0_inv (wh1,wl1, wh1,wl1); |
| 229 | wh1 ^= wh2; wl1 ^= wl2 ^ 20; g6_inv (wh2,wl2, wh2,wl2); |
| 230 | wh2 ^= wh3; wl2 ^= wl3 ^ 19; g2_inv (wh3,wl3, wh3,wl3); |
| 231 | wh3 ^= wh4; wl3 ^= wl4 ^ 18; g8_inv (wh4,wl4, wh4,wl4); |
| 232 | wh4 ^= wh1; wl4 ^= wl1 ^ 17; g4_inv (wh1,wl1, wh1,wl1); |
| 233 | |
| 234 | /* third 8 rounds */ |
| 235 | g0_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 16; wh3 ^= wh2; |
| 236 | g6_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 15; wh4 ^= wh3; |
| 237 | g2_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 14; wh1 ^= wh4; |
| 238 | g8_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 13; wh2 ^= wh1; |
| 239 | g4_inv (wh2,wl2, wh2,wl2); wl3 ^= wl2 ^ 12; wh3 ^= wh2; |
| 240 | g0_inv (wh3,wl3, wh3,wl3); wl4 ^= wl3 ^ 11; wh4 ^= wh3; |
| 241 | g6_inv (wh4,wl4, wh4,wl4); wl1 ^= wl4 ^ 10; wh1 ^= wh4; |
| 242 | g2_inv (wh1,wl1, wh1,wl1); wl2 ^= wl1 ^ 9; wh2 ^= wh1; |
| 243 | |
| 244 | /* last 8 rounds */ |
| 245 | wh1 ^= wh2; wl1 ^= wl2 ^ 8; g8_inv (wh2,wl2, wh2,wl2); |
| 246 | wh2 ^= wh3; wl2 ^= wl3 ^ 7; g4_inv (wh3,wl3, wh3,wl3); |
| 247 | wh3 ^= wh4; wl3 ^= wl4 ^ 6; g0_inv (wh4,wl4, wh4,wl4); |
| 248 | wh4 ^= wh1; wl4 ^= wl1 ^ 5; g6_inv (wh1,wl1, wh1,wl1); |
| 249 | wh1 ^= wh2; wl1 ^= wl2 ^ 4; g2_inv (wh2,wl2, wh2,wl2); |
| 250 | wh2 ^= wh3; wl2 ^= wl3 ^ 3; g8_inv (wh3,wl3, wh3,wl3); |
| 251 | wh3 ^= wh4; wl3 ^= wl4 ^ 2; g4_inv (wh4,wl4, wh4,wl4); |
| 252 | wh4 ^= wh1; wl4 ^= wl1 ^ 1; g0_inv (wh1,wl1, wh1,wl1); |
| 253 | |
| 254 | /* pack into byte vector */ |
| 255 | plain [0] = wh1; plain [1] = wl1; |
| 256 | plain [2] = wh2; plain [3] = wl2; |
| 257 | plain [4] = wh3; plain [5] = wl3; |
| 258 | plain [6] = wh4; plain [7] = wl4; |
| 259 | } |