3 * $Id: mars.c,v 1.2 2004/04/08 01:36:15 mdw Exp $
5 * The MARS block cipher
7 * (c) 2001 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 /*----- Header files ------------------------------------------------------*/
35 #include <mLib/bits.h>
43 /*----- Global variables --------------------------------------------------*/
45 const octet mars_keysz
[] = { KSZ_RANGE
, MARS_KEYSZ
, 0, 56, 4 };
47 /*----- Useful tables -----------------------------------------------------*/
49 static const uint32 s
[512] = MARS_S
;
54 /*----- Main code ---------------------------------------------------------*/
56 /* --- @mars_init@ --- *
58 * Arguments: @mars_ctx *k@ = pointer to key block to fill in
59 * @const void *buf@ = pointer to buffer of key material
60 * @size_t sz@ = size of key material
64 * Use: Initializes a MARS key buffer. MARS accepts key sizes
65 * between 128 and 448 bits which are a multiple of 32 bits.
68 void mars_init(mars_ctx
*k
, const void *buf
, size_t sz
)
77 /* --- Copy the key into the temporary buffer --- */
80 for (i
= 0; i
< sz
/4; i
++) {
88 /* --- Now spit out the actual key material --- */
90 for (j
= 0; j
< 4; j
++) {
93 /* --- Do the linear mixing stage --- */
95 for (i
= 0; i
< 15; i
++) {
96 x
= t
[(i
+ 8)%15] ^ t
[(i
+ 13)%15];
97 t
[i
] ^= ROL32(x
, 3) ^ ((i
<< 2) | j
);
100 /* --- Now do the Feistel stirring stage --- */
103 for (ii
= 0; ii
< 4; ii
++) {
104 for (i
= 0; i
< 15; i
++) {
105 x
= t
[i
] + s
[x
& 511u];
106 t
[i
] = x
= ROL32(x
, 9);
110 /* --- And spit out the key material --- */
112 for (i
= 0; i
< 10; i
++)
113 *kk
++ = t
[(4 * i
)%15];
116 /* --- Finally, fix up the multiplicative entries --- */
118 for (i
= 5; i
< 37; i
+= 2) {
123 /* --- Compute the magic mask value --- */
126 for (ii
= 0; ii
<= 22; ii
++) {
128 if ((x
& 0x3ff) == 0x3ff || (x
& 0x3ff) == 0)
131 m
&= ~(((w
^ (w
<< 1)) | (w
^ (w
>> 1))) | 0x80000003);
133 /* --- Add in the bias entry to fix up the key --- */
135 x
= ROL32(bb
[j
], k
->k
[i
- 1]);
136 k
->k
[i
] = w
^ (x
& m
);
140 /* --- @mars_eblk@, @mars_dblk@ --- *
142 * Arguments: @const mars_ctx *k@ = pointer to key block
143 * @const uint32 s[4]@ = pointer to source block
144 * @uint32 d[4]@ = pointer to destination block
148 * Use: Low-level block encryption and decryption.
151 #define KADD(k, a, b, c, d) a += *k++, b += *k++, c += *k++, d += *k++
152 #define KSUB(k, a, b, c, d) a -= *k++, b -= *k++, c -= *k++, d -= *k++
153 #define IKADD(k, a, b, c, d) d += *--k, c += *--k, b += *--k, a += *--k
154 #define IKSUB(k, a, b, c, d) d -= *--k, c -= *--k, b -= *--k, a -= *--k
156 #define MIX(a, b, c, d) do { \
157 b ^= s0[(a >> 0) & 0xff]; \
158 b += s1[(a >> 8) & 0xff]; \
159 c += s0[(a >> 16) & 0xff]; \
160 d ^= s1[(a >> 24) & 0xff]; \
164 #define IMIX(a, b, c, d) do { \
166 d ^= s1[(a >> 24) & 0xff]; \
167 c -= s0[(a >> 16) & 0xff]; \
168 b -= s1[(a >> 8) & 0xff]; \
169 b ^= s0[(a >> 0) & 0xff]; \
172 #define E(x, y, z, k, a) do { \
173 uint32 kx = *k++, ky = *k++; \
175 a = ROL32(a, 13); z = a * ky; z = ROL32(z, 5); \
176 x = s[y & 511u] ^ z; y = ROL32(y, z); \
177 z = ROL32(z, 5); x ^= z; x = ROL32(x, z); \
180 #define IE(x, y, z, k, a) do { \
181 uint32 ky = *--k, kx = *--k; \
183 a = ROR32(a, 13); y = a + kx; z = ROL32(z, 5); \
184 x = s[y & 511u] ^ z; y = ROL32(y, z); \
185 z = ROL32(z, 5); x ^= z; x = ROL32(x, z); \
188 #define ROUND(k, a, b, c, d) do { \
191 b += x; c += y; d ^= z; \
194 #define IROUND(k, a, b, c, d) do { \
197 b -= x; c -= y; d ^= z; \
200 void mars_eblk(const mars_ctx
*k
, const uint32
*src
, uint32
*dst
)
203 const uint32
*kk
= k
->k
;
205 a
= src
[0], b
= src
[1], c
= src
[2], d
= src
[3];
206 KADD(kk
, a
, b
, c
, d
);
208 MIX(a
, b
, c
, d
); a
+= d
; MIX(b
, c
, d
, a
); b
+= c
;
209 MIX(c
, d
, a
, b
); MIX(d
, a
, b
, c
);
210 MIX(a
, b
, c
, d
); a
+= d
; MIX(b
, c
, d
, a
); b
+= c
;
211 MIX(c
, d
, a
, b
); MIX(d
, a
, b
, c
);
213 ROUND(kk
, a
, b
, c
, d
); ROUND(kk
, b
, c
, d
, a
);
214 ROUND(kk
, c
, d
, a
, b
); ROUND(kk
, d
, a
, b
, c
);
215 ROUND(kk
, a
, b
, c
, d
); ROUND(kk
, b
, c
, d
, a
);
216 ROUND(kk
, c
, d
, a
, b
); ROUND(kk
, d
, a
, b
, c
);
218 ROUND(kk
, a
, d
, c
, b
); ROUND(kk
, b
, a
, d
, c
);
219 ROUND(kk
, c
, b
, a
, d
); ROUND(kk
, d
, c
, b
, a
);
220 ROUND(kk
, a
, d
, c
, b
); ROUND(kk
, b
, a
, d
, c
);
221 ROUND(kk
, c
, b
, a
, d
); ROUND(kk
, d
, c
, b
, a
);
223 IMIX(a
, d
, c
, b
); IMIX(b
, a
, d
, c
);
224 c
-= b
; IMIX(c
, b
, a
, d
); d
-= a
; IMIX(d
, c
, b
, a
);
225 IMIX(a
, d
, c
, b
); IMIX(b
, a
, d
, c
);
226 c
-= b
; IMIX(c
, b
, a
, d
); d
-= a
; IMIX(d
, c
, b
, a
);
228 KSUB(kk
, a
, b
, c
, d
);
229 dst
[0] = a
; dst
[1] = b
; dst
[2] = c
; dst
[3] = d
;
232 void mars_dblk(const mars_ctx
*k
, const uint32
*src
, uint32
*dst
)
235 const uint32
*kk
= k
->k
+ 40;
237 a
= src
[0], b
= src
[1], c
= src
[2], d
= src
[3];
238 IKADD(kk
, a
, b
, c
, d
);
240 MIX(d
, c
, b
, a
); d
+= a
; MIX(c
, b
, a
, d
); c
+= b
;
241 MIX(b
, a
, d
, c
); MIX(a
, d
, c
, b
);
242 MIX(d
, c
, b
, a
); d
+= a
; MIX(c
, b
, a
, d
); c
+= b
;
243 MIX(b
, a
, d
, c
); MIX(a
, d
, c
, b
);
245 IROUND(kk
, d
, c
, b
, a
); IROUND(kk
, c
, b
, a
, d
);
246 IROUND(kk
, b
, a
, d
, c
); IROUND(kk
, a
, d
, c
, b
);
247 IROUND(kk
, d
, c
, b
, a
); IROUND(kk
, c
, b
, a
, d
);
248 IROUND(kk
, b
, a
, d
, c
); IROUND(kk
, a
, d
, c
, b
);
250 IROUND(kk
, d
, a
, b
, c
); IROUND(kk
, c
, d
, a
, b
);
251 IROUND(kk
, b
, c
, d
, a
); IROUND(kk
, a
, b
, c
, d
);
252 IROUND(kk
, d
, a
, b
, c
); IROUND(kk
, c
, d
, a
, b
);
253 IROUND(kk
, b
, c
, d
, a
); IROUND(kk
, a
, b
, c
, d
);
255 IMIX(d
, a
, b
, c
); IMIX(c
, d
, a
, b
);
256 b
-= c
; IMIX(b
, c
, d
, a
); a
-= d
; IMIX(a
, b
, c
, d
);
257 IMIX(d
, a
, b
, c
); IMIX(c
, d
, a
, b
);
258 b
-= c
; IMIX(b
, c
, d
, a
); a
-= d
; IMIX(a
, b
, c
, d
);
260 IKSUB(kk
, a
, b
, c
, d
);
261 dst
[0] = a
; dst
[1] = b
; dst
[2] = c
; dst
[3] = d
;
264 BLKC_TEST(MARS
, mars
)
266 /*----- That's all, folks -------------------------------------------------*/