[BACK]Return to skipjack.c CVS log [TXT][DIR] Up to [local] / sys / crypto

Annotation of sys/crypto/skipjack.c, Revision 1.1.1.1

1.1       nbrk        1: /*     $OpenBSD: skipjack.c,v 1.4 2006/03/23 15:32:03 mickey Exp $     */
                      2:
                      3: /*
                      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.
                      7:  *
                      8:  * based on unoptimized implementation of
                      9:  * Panu Rissanen <bande@lut.fi> 960624
                     10:  *
                     11:  * SKIPJACK and KEA Algorithm Specifications
                     12:  * Version 2.0
                     13:  * 29 May 1998
                     14: */
                     15:
                     16: #include <sys/param.h>
                     17: #include <crypto/skipjack.h>
                     18: #include <sys/malloc.h>
                     19:
                     20: static const u_int8_t ftable[0x100] =
                     21: {
                     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
                     54: };
                     55:
                     56: /*
                     57:  * For each key byte generate a table to represent the function
                     58:  *    ftable [in ^ keybyte]
                     59:  *
                     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
                     62:  * k0, k1..k9
                     63:  */
                     64: void
                     65: subkey_table_gen (u_int8_t *key, u_int8_t **key_tables)
                     66: {
                     67:        int i, k;
                     68:
                     69:        for (k = 0; k < 10; k++) {
                     70:                u_int8_t   key_byte = key [k];
                     71:                u_int8_t * table = (u_int8_t *) malloc(0x100, M_CRYPTO_DATA,
                     72:                                                       M_WAITOK);
                     73:                key_tables [k] = table;
                     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: }

CVSweb