3 * The MARS block cipher
5 * (c) 2001 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Catacomb.
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
28 /*----- Header files ------------------------------------------------------*/
33 #include <mLib/bits.h>
40 /*----- Global variables --------------------------------------------------*/
42 const octet mars_keysz
[] = { KSZ_RANGE
, MARS_KEYSZ
, 0, 56, 4 };
44 /*----- Useful tables -----------------------------------------------------*/
46 extern const uint32 mars_s
[512];
47 #define s0 (mars_s + 0)
48 #define s1 (mars_s + 256)
49 #define bb (mars_s + 265)
51 /*----- Main code ---------------------------------------------------------*/
53 /* --- @mars_init@ --- *
55 * Arguments: @mars_ctx *k@ = pointer to key block to fill in
56 * @const void *buf@ = pointer to buffer of key material
57 * @size_t sz@ = size of key material
61 * Use: Initializes a MARS key buffer. MARS accepts key sizes
62 * between 128 and 448 bits which are a multiple of 32 bits.
65 void mars_init(mars_ctx
*k
, const void *buf
, size_t sz
)
74 /* --- Copy the key into the temporary buffer --- */
77 for (i
= 0; i
< sz
/4; i
++) {
85 /* --- Now spit out the actual key material --- */
87 for (j
= 0; j
< 4; j
++) {
90 /* --- Do the linear mixing stage --- */
92 for (i
= 0; i
< 15; i
++) {
93 x
= t
[(i
+ 8)%15] ^ t
[(i
+ 13)%15];
94 t
[i
] ^= ROL32(x
, 3) ^ ((i
<< 2) | j
);
97 /* --- Now do the Feistel stirring stage --- */
100 for (ii
= 0; ii
< 4; ii
++) {
101 for (i
= 0; i
< 15; i
++) {
102 x
= t
[i
] + mars_s
[x
& 511u];
103 t
[i
] = x
= ROL32(x
, 9);
107 /* --- And spit out the key material --- */
109 for (i
= 0; i
< 10; i
++)
110 *kk
++ = t
[(4 * i
)%15];
113 /* --- Finally, fix up the multiplicative entries --- */
115 for (i
= 5; i
< 37; i
+= 2) {
120 /* --- Compute the magic mask value --- */
123 for (ii
= 0; ii
<= 22; ii
++) {
125 if ((x
& 0x3ff) == 0x3ff || (x
& 0x3ff) == 0)
128 m
&= ~(((w
^ (w
<< 1)) | (w
^ (w
>> 1))) | 0x80000003);
130 /* --- Add in the bias entry to fix up the key --- */
132 x
= ROL32(bb
[j
], k
->k
[i
- 1]);
133 k
->k
[i
] = w
^ (x
& m
);
137 /* --- @mars_eblk@, @mars_dblk@ --- *
139 * Arguments: @const mars_ctx *k@ = pointer to key block
140 * @const uint32 s[4]@ = pointer to source block
141 * @uint32 d[4]@ = pointer to destination block
145 * Use: Low-level block encryption and decryption.
148 #define KADD(k, a, b, c, d) a += *k++, b += *k++, c += *k++, d += *k++
149 #define KSUB(k, a, b, c, d) a -= *k++, b -= *k++, c -= *k++, d -= *k++
150 #define IKADD(k, a, b, c, d) d += *--k, c += *--k, b += *--k, a += *--k
151 #define IKSUB(k, a, b, c, d) d -= *--k, c -= *--k, b -= *--k, a -= *--k
153 #define MIX(a, b, c, d) do { \
154 b ^= s0[(a >> 0) & 0xff]; \
155 b += s1[(a >> 8) & 0xff]; \
156 c += s0[(a >> 16) & 0xff]; \
157 d ^= s1[(a >> 24) & 0xff]; \
161 #define IMIX(a, b, c, d) do { \
163 d ^= s1[(a >> 24) & 0xff]; \
164 c -= s0[(a >> 16) & 0xff]; \
165 b -= s1[(a >> 8) & 0xff]; \
166 b ^= s0[(a >> 0) & 0xff]; \
169 #define E(x, y, z, k, a) do { \
170 uint32 kx = *k++, ky = *k++; \
172 a = ROL32(a, 13); z = a * ky; z = ROL32(z, 5); \
173 x = mars_s[y & 511u] ^ z; y = ROL32(y, z); \
174 z = ROL32(z, 5); x ^= z; x = ROL32(x, z); \
177 #define IE(x, y, z, k, a) do { \
178 uint32 ky = *--k, kx = *--k; \
180 a = ROR32(a, 13); y = a + kx; z = ROL32(z, 5); \
181 x = mars_s[y & 511u] ^ z; y = ROL32(y, z); \
182 z = ROL32(z, 5); x ^= z; x = ROL32(x, z); \
185 #define ROUND(k, a, b, c, d) do { \
188 b += x; c += y; d ^= z; \
191 #define IROUND(k, a, b, c, d) do { \
194 b -= x; c -= y; d ^= z; \
197 void mars_eblk(const mars_ctx
*k
, const uint32
*src
, uint32
*dst
)
200 const uint32
*kk
= k
->k
;
202 a
= src
[0], b
= src
[1], c
= src
[2], d
= src
[3];
203 KADD(kk
, a
, b
, c
, d
);
205 MIX(a
, b
, c
, d
); a
+= d
; MIX(b
, c
, d
, a
); b
+= c
;
206 MIX(c
, d
, a
, b
); MIX(d
, a
, b
, c
);
207 MIX(a
, b
, c
, d
); a
+= d
; MIX(b
, c
, d
, a
); b
+= c
;
208 MIX(c
, d
, a
, b
); MIX(d
, a
, b
, c
);
210 ROUND(kk
, a
, b
, c
, d
); ROUND(kk
, b
, c
, d
, a
);
211 ROUND(kk
, c
, d
, a
, b
); ROUND(kk
, d
, a
, b
, c
);
212 ROUND(kk
, a
, b
, c
, d
); ROUND(kk
, b
, c
, d
, a
);
213 ROUND(kk
, c
, d
, a
, b
); ROUND(kk
, d
, a
, b
, c
);
215 ROUND(kk
, a
, d
, c
, b
); ROUND(kk
, b
, a
, d
, c
);
216 ROUND(kk
, c
, b
, a
, d
); ROUND(kk
, d
, c
, b
, a
);
217 ROUND(kk
, a
, d
, c
, b
); ROUND(kk
, b
, a
, d
, c
);
218 ROUND(kk
, c
, b
, a
, d
); ROUND(kk
, d
, c
, b
, a
);
220 IMIX(a
, d
, c
, b
); IMIX(b
, a
, d
, c
);
221 c
-= b
; IMIX(c
, b
, a
, d
); d
-= a
; IMIX(d
, c
, b
, a
);
222 IMIX(a
, d
, c
, b
); IMIX(b
, a
, d
, c
);
223 c
-= b
; IMIX(c
, b
, a
, d
); d
-= a
; IMIX(d
, c
, b
, a
);
225 KSUB(kk
, a
, b
, c
, d
);
226 dst
[0] = a
; dst
[1] = b
; dst
[2] = c
; dst
[3] = d
;
229 void mars_dblk(const mars_ctx
*k
, const uint32
*src
, uint32
*dst
)
232 const uint32
*kk
= k
->k
+ 40;
234 a
= src
[0], b
= src
[1], c
= src
[2], d
= src
[3];
235 IKADD(kk
, a
, b
, c
, d
);
237 MIX(d
, c
, b
, a
); d
+= a
; MIX(c
, b
, a
, d
); c
+= b
;
238 MIX(b
, a
, d
, c
); MIX(a
, d
, c
, b
);
239 MIX(d
, c
, b
, a
); d
+= a
; MIX(c
, b
, a
, d
); c
+= b
;
240 MIX(b
, a
, d
, c
); MIX(a
, d
, c
, b
);
242 IROUND(kk
, d
, c
, b
, a
); IROUND(kk
, c
, b
, a
, d
);
243 IROUND(kk
, b
, a
, d
, c
); IROUND(kk
, a
, d
, c
, b
);
244 IROUND(kk
, d
, c
, b
, a
); IROUND(kk
, c
, b
, a
, d
);
245 IROUND(kk
, b
, a
, d
, c
); IROUND(kk
, a
, d
, c
, b
);
247 IROUND(kk
, d
, a
, b
, c
); IROUND(kk
, c
, d
, a
, b
);
248 IROUND(kk
, b
, c
, d
, a
); IROUND(kk
, a
, b
, c
, d
);
249 IROUND(kk
, d
, a
, b
, c
); IROUND(kk
, c
, d
, a
, b
);
250 IROUND(kk
, b
, c
, d
, a
); IROUND(kk
, a
, b
, c
, d
);
252 IMIX(d
, a
, b
, c
); IMIX(c
, d
, a
, b
);
253 b
-= c
; IMIX(b
, c
, d
, a
); a
-= d
; IMIX(a
, b
, c
, d
);
254 IMIX(d
, a
, b
, c
); IMIX(c
, d
, a
, b
);
255 b
-= c
; IMIX(b
, c
, d
, a
); a
-= d
; IMIX(a
, b
, c
, d
);
257 IKSUB(kk
, a
, b
, c
, d
);
258 dst
[0] = a
; dst
[1] = b
; dst
[2] = c
; dst
[3] = d
;
261 BLKC_TEST(MARS
, mars
)
263 /*----- That's all, folks -------------------------------------------------*/