3 * $Id: twofish-mktab.c,v 1.1 2000/06/17 12:10:17 mdw Exp $
5 * Build constant tables for Twofish
7 * (c) 2000 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
14 * Catacomb is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * Catacomb is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with Catacomb; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
32 * $Log: twofish-mktab.c,v $
33 * Revision 1.1 2000/06/17 12:10:17 mdw
38 /*----- Header files ------------------------------------------------------*/
43 #include <mLib/bits.h>
45 /*----- Data structures ---------------------------------------------------*/
47 typedef struct { octet t
[4][16]; } t_tab
;
48 typedef struct { octet q
[256]; } q_tab
;
50 /*----- Various Twofish tables --------------------------------------------*/
52 /* --- The t-tables --- */
54 static const t_tab qt0
= {{
55 { 0x8, 0x1, 0x7, 0xd, 0x6, 0xf, 0x3, 0x2,
56 0x0, 0xb, 0x5, 0x9, 0xe, 0xc, 0xa, 0x4 },
57 { 0xe, 0xc, 0xb, 0x8, 0x1, 0x2, 0x3, 0x5,
58 0xf, 0x4, 0xa, 0x6, 0x7, 0x0, 0x9, 0xd },
59 { 0xb, 0xa, 0x5, 0xe, 0x6, 0xd, 0x9, 0x0,
60 0xc, 0x8, 0xf, 0x3, 0x2, 0x4, 0x7, 0x1 },
61 { 0xd, 0x7, 0xf, 0x4, 0x1, 0x2, 0x6, 0xe,
62 0x9, 0xb, 0x3, 0x0, 0x8, 0x5, 0xc, 0xa }
65 static const t_tab qt1
= {{
66 { 0x2, 0x8, 0xb, 0xd, 0xf, 0x7, 0x6, 0xe,
67 0x3, 0x1, 0x9, 0x4, 0x0, 0xa, 0xc, 0x5 },
68 { 0x1, 0xe, 0x2, 0xb, 0x4, 0xc, 0x3, 0x7,
69 0x6, 0xd, 0xa, 0x5, 0xf, 0x9, 0x0, 0x8 },
70 { 0x4, 0xc, 0x7, 0x5, 0x1, 0x6, 0x9, 0xa,
71 0x0, 0xe, 0xd, 0x8, 0x2, 0xb, 0x3, 0xf },
72 { 0xb, 0x9, 0x5, 0x1, 0xc, 0x3, 0xd, 0xe,
73 0x6, 0x4, 0x7, 0xf, 0x2, 0x0, 0x8, 0xa }
78 /* --- The MDS and Reed-Solomon matrices --- */
80 static const octet mds
[16] = {
81 0x01, 0xef, 0x5b, 0x5b,
82 0x5b, 0xef, 0xef, 0x01,
83 0xef, 0x5b, 0x01, 0xef,
84 0xef, 0x01, 0xef, 0x5b
87 static const octet rs
[32] = {
88 0x01, 0xa4, 0x55, 0x87, 0x5a, 0x58, 0xdb, 0x9e,
89 0xa4, 0x56, 0x82, 0xf3, 0x1e, 0xc6, 0x68, 0xe5,
90 0x02, 0xa1, 0xfc, 0xc1, 0x47, 0xae, 0x3d, 0x19,
91 0xa4, 0x55, 0x87, 0x5a, 0x58, 0xdb, 0x9e, 0x03
94 /*----- Magic macros ------------------------------------------------------*/
96 #define ROR4(x) ((((x) >> 1) | ((x) << 3)) & 15)
98 /*----- Building and printing @q@ tables ----------------------------------*/
102 * Arguments: @q_tab *q@ = pointer to output @q@ table
103 * @const t_tab *t@ = pointer to input @t@ table
104 * @const char *name@ = name of @q@ table
108 * Use: Constructs a 256-entry @q@-table.
111 static void mkq(q_tab
*q
, const t_tab
*t
, const char *name
)
116 /* --- Ensure the t-table is well-formed --- */
118 for (i
= 0; i
< 4; i
++) {
122 for (j
= 0; j
< 16; j
++) {
124 fprintf(stderr
, "duplicate %i in %s[%i] (col %i and %i)\n",
125 t
->t
[i
][j
], name
, i
, j
, f
[t
->t
[i
][j
]]);
135 /* --- Construct the @q@ table --- */
137 for (i
= 0; i
< 256; i
++) {
138 int a
= i
>> 4, b
= i
& 15;
139 int aa
= t
->t
[0][a
^ b
], bb
= t
->t
[1][a
^ ((a
<< 3) & 15) ^ ROR4(b
)];
140 a
= t
->t
[2][aa
^ bb
], b
= t
->t
[3][aa
^ ((aa
<< 3) & 15) ^ ROR4(bb
)];
141 q
->q
[i
] = a
| (b
<< 4);
144 /* Consider testing @q@ for linear and differential properties here */
147 /* --- @printq@ --- *
149 * Arguments: @const q_tab *t@ = pointer to table
150 * @const char *name@ = pointer to table name
154 * Use: Prints a q table.
157 static void printq(const q_tab
*q
, const char *name
)
163 #define TWOFISH_%s { \\\n\
166 for (i
= 0; i
< 256; i
++) {
167 printf("0x%02x", q
->q
[i
]);
170 fputs(" \\\n}\n\n", stdout
);
172 fputs(", \\\n ", stdout
);
178 /*----- GF(2^8) arithmetic ------------------------------------------------*/
180 #define MDS_MOD 0x169
185 * Arguments: @unsigned x, y@ = polynomials over %$\mathrm{GF}(2^8)$%
186 * @unsigned m@ = modulus
188 * Returns: The product of two polynomials.
190 * Use: Computes a product of polynomials, quite slowly.
193 static unsigned mul(unsigned x
, unsigned y
, unsigned m
)
198 for (i
= 0; i
< 8; i
++) {
212 * Arguments: @octet *d@ = destination vector
213 * @const octet *p@ = matrix of bytes
214 * @const octet *q@ = vector from somewhere else
215 * @size_t r@ = size of destination or number of rows in matrix
216 * @size_t n@ = length of row and vector
217 * @unsigned m@ = modulus polynomial
221 * Use: Computes an inner product of matrices over the finite field
222 * %$\mathrm{GF}(2^8)[x]/m(x)$%. This isn't particularly rapid.
225 static void mmul(octet
*d
, const octet
*p
, const octet
*q
,
226 size_t r
, size_t n
, unsigned m
)
233 for (i
= 0; i
< n
; i
++)
234 a
^= mul(*p
++, *qq
++, m
);
246 * Use: Prints the MDS/q table.
249 static void qmds(void)
253 static const q_tab
*q
[4] = { &q1
, &q0
, &q1
, &q0
};
255 for (i
= 0; i
< 4; i
++) {
256 octet in
[4] = { 0, 0, 0, 0 };
259 for (j
= 0; j
< 256; j
++) {
261 mmul(out
, mds
, in
, 4, 4, MDS_MOD
);
262 t
[i
][j
] = LOAD32_L(out
);
267 /* --- Expanded MDS tables --- *\n\
269 * The table contains output vectors for computing the result of pushing\n\
270 * bytes through appropriate @q@ tables and the MDS matrix.\n\
273 #define TWOFISH_QMDS { \\");
274 for (i
= 0; i
< 4; i
++) {
275 fputs(" { ", stdout
);
276 for (j
= 0; j
< 256; j
++) {
277 printf("0x%08lx", (unsigned long)t
[i
][j
]);
284 } else if (j
% 4 == 3)
285 fputs(", \\\n ", stdout
);
300 * Use: Produces the log and antilog tables for doing the RS
301 * arithmetic efficiently.
304 static void rslog(void)
313 for (i
= 0; i
< 256; i
++) {
322 for (i
= 0; i
< 32; i
++) {
323 if (rslog
[rs
[i
]] > x
)
328 /* --- Reed-Solomon log tables --- *\n\
330 * The Reed-Solomon multiplies are accelerated by using log tables.\n\
333 #define TWOFISH_RSLOG { \\\n\
336 for (i
= 0; i
< 256; i
++) {
337 printf("0x%02x", rslog
[i
]);
341 fputs(", \\\n ", stdout
);
347 #define TWOFISH_RSEXP { \\\n\
350 for (i
= 0; i
< 255 + x
+ 1; i
++) {
351 printf("0x%02x", rsexp
[i
% 255]);
355 fputs(", \\\n ", stdout
);
361 /* --- Reed-Solomon matrix with log entries --- */\n\
363 #define TWOFISH_RS { \\\n\
366 for (i
= 0; i
< 32; i
++) {
367 printf("0x%02x", rslog
[rs
[i
]]);
371 fputs(", \\\n ", stdout
);
377 /*----- Main program ------------------------------------------------------*/
386 * Twofish q tables [generated]\n\
389 #ifndef CATACOMB_TWOFISH_TAB_H
390 #define CATACOMB_TWOFISH_TAB_H
394 /* --- The q tables --- */
397 /* --- Precomputed @q@ tables --- */\n\
399 mkq(&q0
, &qt0
, "qt0");
400 mkq(&q1
, &qt1
, "qt1");
404 /* --- The MDS/q tables --- */
413 if (fclose(stdout
)) {
414 fprintf(stderr
, "error writing data\n");
421 /*----- That's all, folks -------------------------------------------------*/