4ea85b6cb2a024bee6e7bd537e68110ac35b6655
5 * (c) 2000 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>
41 /*----- Global variables --------------------------------------------------*/
43 const octet rc2_keysz
[] = { KSZ_RANGE
, RC2_KEYSZ
, 1, 128, 1 };
45 /*----- Important tables --------------------------------------------------*/
47 static const octet pi
[256] = RC2_PI
;
49 /*----- Main code ---------------------------------------------------------*/
51 /* --- @rc2_braindamage@ --- *
53 * Arguments: @rc2_ctx *k@ = pointer to context to initialize
54 * @const void *buf@ = pointer to key material
55 * @size_t sz@ = size of key material in bytes
56 * @unsigned eb@ = desired effective key size, in bits
60 * Use: Initializes an RC2 expanded key, and braindamages it to the
61 * requested effective key size. This is here for compatibility
62 * reasons. You should be using @rc2_init@ in normal code,
63 * which doesn't actually apply braindamage.
66 void rc2_braindamage(rc2_ctx
*k
, const void *buf
, size_t sz
, unsigned eb
)
76 /* --- Compute the braindamage parameters --- */
79 tm
= 0xff & ((1 << (8 + eb
- 8 * t8
)) - 1);
81 /* --- Copy and expand the initial key --- */
87 for (i
= sz
; i
< sizeof(l
); i
++)
88 l
[i
] = pi
[U8(l
[i
- 1] + l
[i
- sz
])];
90 /* --- Braindamage the key --- */
96 l
[i
] = pi
[U8(l
[i
+ 1] ^ l
[i
+ t8
])];
99 /* --- Write it to the key block --- */
102 for (i
= 0; i
< sizeof(l
); i
+= 2)
103 *kk
++ = LOAD16_L(l
+ i
);
107 /* --- @rc2_init@ --- *
109 * Arguments: @rc2_ctx *k@ = pointer to context to initialize
110 * @const void *buf@ = pointer to key material
111 * @size_t sz@ = size of key material in bytes
115 * Use: Initializes an RC2 expanded key. The effective key size is
116 * set to be equal to the real key size, in bits.
119 void rc2_init(rc2_ctx
*k
, const void *buf
, size_t sz
)
121 rc2_braindamage(k
, buf
, sz
, sz
* 8);
124 /*----- Encryption and decryption -----------------------------------------*/
126 #define MIX(a, b, c, d, r, kk) do { \
127 a += *kk++ + (d & c) + (~d & b); \
131 #define MASH(a, d, k) do { \
135 #define UNMIX(a, b, c, d, r, kk) do { \
137 a -= *--kk + (d & c) + (~d & b); \
140 #define UNMASH(a, d, k) do { \
144 /* --- @rc2_eblk@, @rc2_dblk@ --- *
146 * Arguments: @const rc2_ctx *k@ = pointer to RC2 context
147 * @const uint32 s[2]@ = pointer to source block
148 * @const uint32 d[2]@ = pointer to destination block
152 * Use: Low-level block encryption and decryption.
155 void rc2_eblk(const rc2_ctx
*k
, const uint32
*s
, uint32
*dst
)
157 uint16 a
= U16(s
[0] >> 0), b
= U16(s
[0] >> 16);
158 uint16 c
= U16(s
[1] >> 0), d
= U16(s
[1] >> 16);
159 const uint16
*kk
= k
->k
;
161 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
162 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
163 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
164 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
165 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
166 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
167 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
168 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
169 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
170 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
171 MASH(a
, d
, k
->k
); MASH(b
, a
, k
->k
);
172 MASH(c
, b
, k
->k
); MASH(d
, c
, k
->k
);
173 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
174 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
175 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
176 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
177 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
178 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
179 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
180 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
181 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
182 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
183 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
184 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
185 MASH(a
, d
, k
->k
); MASH(b
, a
, k
->k
);
186 MASH(c
, b
, k
->k
); MASH(d
, c
, k
->k
);
187 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
188 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
189 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
190 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
191 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
192 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
193 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
194 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
195 MIX(a
, b
, c
, d
, 1, kk
); MIX(b
, c
, d
, a
, 2, kk
);
196 MIX(c
, d
, a
, b
, 3, kk
); MIX(d
, a
, b
, c
, 5, kk
);
198 dst
[0] = a
| (b
<< 16); dst
[1] = c
| (d
<< 16);
201 void rc2_dblk(const rc2_ctx
*k
, const uint32
*s
, uint32
*dst
)
203 uint16 a
= U16(s
[0] >> 0), b
= U16(s
[0] >> 16);
204 uint16 c
= U16(s
[1] >> 0), d
= U16(s
[1] >> 16);
205 const uint16
*kk
= k
->k
+ 64;
207 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
208 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
209 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
210 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
211 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
212 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
213 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
214 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
215 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
216 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
217 UNMASH(d
, c
, k
->k
); UNMASH(c
, b
, k
->k
);
218 UNMASH(b
, a
, k
->k
); UNMASH(a
, d
, k
->k
);
219 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
220 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
221 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
222 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
223 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
224 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
225 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
226 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
227 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
228 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
229 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
230 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
231 UNMASH(d
, c
, k
->k
); UNMASH(c
, b
, k
->k
);
232 UNMASH(b
, a
, k
->k
); UNMASH(a
, d
, k
->k
);
233 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
234 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
235 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
236 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
237 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
238 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
239 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
240 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
241 UNMIX(d
, a
, b
, c
, 5, kk
); UNMIX(c
, d
, a
, b
, 3, kk
);
242 UNMIX(b
, c
, d
, a
, 2, kk
); UNMIX(a
, b
, c
, d
, 1, kk
);
244 dst
[0] = a
| (b
<< 16); dst
[1] = c
| (d
<< 16);
247 /*----- Custom test rig ---------------------------------------------------*
249 * I need to test the braindamage feature.
254 #include <mLib/quis.h>
255 #include <mLib/testrig.h>
257 static int verify(dstr
*v
)
260 uint32 p
[RC2_BLKSZ
/ 4];
261 uint32 c
[RC2_BLKSZ
/ 4];
262 uint32 d
[RC2_BLKSZ
/ 4];
264 unsigned bd
= *(unsigned *)v
[1].buf
;
267 /* --- Initialize the key buffer --- */
269 dstr_ensure(&b
, RC2_BLKSZ
);
271 rc2_braindamage(&k
, v
[0].buf
, v
[0].len
, bd
);
272 BLKC_LOAD(RC2
, p
, v
[2].buf
);
273 BLKC_LOAD(RC2
, c
, v
[3].buf
);
275 /* --- Test encryption --- */
277 BLKC_MOVE(RC2
, d
, p
);
279 BLKC_STORE(RC2
, b
.buf
, d
);
280 if (memcmp(b
.buf
, v
[3].buf
, RC2_BLKSZ
)) {
282 printf("\nfail encryption:"
284 type_hex
.dump(&v
[0], stdout
);
285 printf("\n\tbraindamage= %u", bd
);
286 printf("\n\tplaintext = "); type_hex
.dump(&v
[2], stdout
);
287 printf("\n\texpected = "); type_hex
.dump(&v
[3], stdout
);
288 printf("\n\tcalculated = "); type_hex
.dump(&b
, stdout
);
292 /* --- Test decryption --- */
294 BLKC_MOVE(RC2
, d
, c
);
296 BLKC_STORE(RC2
, b
.buf
, d
);
297 if (memcmp(b
.buf
, v
[2].buf
, RC2_BLKSZ
)) {
299 printf("\nfail decryption:"
301 type_hex
.dump(&v
[0], stdout
);
302 printf("\n\tbraindamage= %u", bd
);
303 printf("\n\tciphertext = "); type_hex
.dump(&v
[3], stdout
);
304 printf("\n\texpected = "); type_hex
.dump(&v
[2], stdout
);
305 printf("\n\tcalculated = "); type_hex
.dump(&b
, stdout
);
314 static test_chunk defs
[] = {
315 { "rc2", verify
, { &type_hex
, &type_int
, &type_hex
, &type_hex
, 0 } },
319 int main(int argc
, char *argv
[])
321 test_run(argc
, argv
, defs
, SRCDIR
"/t/rc2");
327 /*----- That's all, folks -------------------------------------------------*/