79ba130c |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: ecb-def.h,v 1.1 1999/12/10 23:16:39 mdw Exp $ |
4 | * |
5 | * Definitions electronic code book mode |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Catacomb. |
13 | * |
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. |
18 | * |
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. |
23 | * |
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, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: ecb-def.h,v $ |
33 | * Revision 1.1 1999/12/10 23:16:39 mdw |
34 | * Split mode macros into interface and implementation. |
35 | * |
36 | */ |
37 | |
38 | #ifndef CATACOMB_ECB_DEF_H |
39 | #define CATACOMB_ECB_DEF_H |
40 | |
41 | #ifdef __cplusplus |
42 | extern "C" { |
43 | #endif |
44 | |
45 | /*----- Header files ------------------------------------------------------*/ |
46 | |
47 | #include <assert.h> |
48 | #include <string.h> |
49 | |
50 | #include <mLib/bits.h> |
51 | #include <mLib/sub.h> |
52 | |
53 | #ifndef CATACOMB_BLKC_H |
54 | # include "blkc.h" |
55 | #endif |
56 | |
57 | #ifndef CATACOMB_GCIPHER_H |
58 | # include "gcipher.h" |
59 | #endif |
60 | |
61 | /*----- Macros ------------------------------------------------------------*/ |
62 | |
63 | /* --- @ECB_DEF@ --- * |
64 | * |
65 | * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher |
66 | * |
67 | * Use: Creates an implementation for ECB stealing mode. |
68 | */ |
69 | |
70 | #define ECB_DEF(PRE, pre) \ |
71 | \ |
72 | /* --- @pre_ecbsetkey@ --- * \ |
73 | * \ |
74 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
75 | * @const pre_ctx *k@ = pointer to cipher context \ |
76 | * \ |
77 | * Returns: --- \ |
78 | * \ |
79 | * Use: Sets the ECB context to use a different cipher key. \ |
80 | */ \ |
81 | \ |
82 | void pre##_ecbsetkey(pre##_ecbctx *ctx, const pre##_ctx *k) \ |
83 | { \ |
84 | ctx->ctx = *k; \ |
85 | } \ |
86 | \ |
87 | /* --- @pre_ecbinit@ --- * \ |
88 | * \ |
89 | * Arguments: @pre_ecbctx *ctx@ = pointer to cipher context \ |
90 | * @const void *key@ = pointer to the key buffer \ |
91 | * @size_t sz@ = size of the key \ |
92 | * @const void *iv@ = pointer to initialization vector \ |
93 | * \ |
94 | * Returns: --- \ |
95 | * \ |
96 | * Use: Initializes an ECB context ready for use. This is \ |
97 | * equivalent to calls to @pre_init@ and @pre_setkey@. \ |
98 | */ \ |
99 | \ |
100 | void pre##_ecbinit(pre##_ecbctx *ctx, \ |
101 | const void *key, size_t sz, \ |
102 | const void *iv) \ |
103 | { \ |
104 | pre##_init(&ctx->ctx, key, sz); \ |
105 | } \ |
106 | \ |
107 | /* --- @pre_ecbencrypt@ --- * \ |
108 | * \ |
109 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
110 | * @const void *src@ = pointer to source data \ |
111 | * @void *dest@ = pointer to destination data \ |
112 | * @size_t sz@ = size of block to be encrypted \ |
113 | * \ |
114 | * Returns: --- \ |
115 | * \ |
116 | * Use: Encrypts a block with a block cipher in ECB mode, with \ |
117 | * ciphertext stealing and other clever tricks. \ |
118 | * Essentially, data can be encrypted in arbitrary sized \ |
119 | * chunks, although decryption must use the same chunks. \ |
120 | */ \ |
121 | \ |
122 | void pre##_ecbencrypt(pre##_ecbctx *ctx, \ |
123 | const void *src, void *dest, \ |
124 | size_t sz) \ |
125 | { \ |
126 | const octet *s = src; \ |
127 | octet *d = dest; \ |
128 | \ |
129 | /* --- Empty blocks are trivial --- */ \ |
130 | \ |
131 | if (!sz) \ |
132 | return; \ |
133 | \ |
134 | /* --- Short blocks aren't allowed in ECB --- * \ |
135 | * \ |
136 | * There's absolutely nothing secure I can do with them. \ |
137 | */ \ |
138 | \ |
139 | assert(((void)"ECB must have at least one whole block to work with", \ |
140 | sz >= PRE##_BLKSZ)); \ |
141 | \ |
142 | /* --- Do the main chunk of encryption --- * \ |
143 | * \ |
144 | * This will do the whole lot if it's a whole number of blocks. Just \ |
145 | * give each block to the cipher in turn. This is trivial. \ |
146 | * Hopefully... \ |
147 | */ \ |
148 | \ |
149 | while (sz >= 2 * PRE##_BLKSZ || sz == PRE##_BLKSZ) { \ |
150 | uint32 x[PRE##_BLKSZ / 4]; \ |
151 | BLKC_LOAD(PRE, x, s); \ |
152 | pre##_eblk(&ctx->ctx, x, x); \ |
153 | BLKC_STORE(PRE, d, x); \ |
154 | s += PRE##_BLKSZ; \ |
155 | d += PRE##_BLKSZ; \ |
156 | sz -= PRE##_BLKSZ; \ |
157 | } \ |
158 | \ |
159 | /* --- Do the tail-end block and bit-left-over --- * \ |
160 | * \ |
161 | * This isn't very efficient. That shouldn't matter much. \ |
162 | */ \ |
163 | \ |
164 | if (sz) { \ |
165 | uint32 x[PRE##_BLKSZ / 4]; \ |
166 | octet b[PRE##_BLKSZ]; \ |
167 | unsigned i; \ |
168 | \ |
169 | /* --- Let @sz@ be the size of the partial block --- */ \ |
170 | \ |
171 | sz -= PRE##_BLKSZ; \ |
172 | \ |
173 | /* --- First stage --- * \ |
174 | * \ |
175 | * Read in the current block, and encrypt it. The first part of \ |
176 | * the result is the partial ciphertext block. Don't write that \ |
177 | * out yet, because I've not read the partial plaintext block. \ |
178 | */ \ |
179 | \ |
180 | BLKC_LOAD(PRE, x, s); \ |
181 | pre##_eblk(&ctx->ctx, x, x); \ |
182 | BLKC_STORE(PRE, b, x); \ |
183 | \ |
184 | /* --- Second stage --- * \ |
185 | * \ |
186 | * Now move in the partial plaintext block, writing out the \ |
187 | * ciphertext as I go. Then encrypt, and write the complete \ |
188 | * ciphertext block. \ |
189 | */ \ |
190 | \ |
191 | s += PRE##_BLKSZ; \ |
192 | d += PRE##_BLKSZ; \ |
193 | for (i = 0; i < sz; i++) { \ |
194 | register octet y = b[i]; \ |
195 | b[i] = s[i]; \ |
196 | d[i] = y; \ |
197 | } \ |
198 | BLKC_LOAD(PRE, x, b); \ |
199 | pre##_eblk(&ctx->ctx, x, x); \ |
200 | BLKC_STORE(PRE, d - PRE##_BLKSZ, x); \ |
201 | } \ |
202 | \ |
203 | /* --- Done --- */ \ |
204 | \ |
205 | return; \ |
206 | } \ |
207 | \ |
208 | /* --- @pre_ecbdecrypt@ --- * \ |
209 | * \ |
210 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
211 | * @const void *src@ = pointer to source data \ |
212 | * @void *dest@ = pointer to destination data \ |
213 | * @size_t sz@ = size of block to be encrypted \ |
214 | * \ |
215 | * Returns: --- \ |
216 | * \ |
217 | * Use: Decrypts a block with a block cipher in ECB mode, with \ |
218 | * ciphertext stealing and other clever tricks. \ |
219 | * Essentially, data can be encrypted in arbitrary sized \ |
220 | * chunks, although decryption must use the same chunks. \ |
221 | */ \ |
222 | \ |
223 | void pre##_ecbdecrypt(pre##_ecbctx *ctx, \ |
224 | const void *src, void *dest, \ |
225 | size_t sz) \ |
226 | { \ |
227 | const octet *s = src; \ |
228 | octet *d = dest; \ |
229 | \ |
230 | /* --- Empty blocks are trivial --- */ \ |
231 | \ |
232 | if (!sz) \ |
233 | return; \ |
234 | \ |
235 | /* --- Short blocks aren't allowed in ECB --- * \ |
236 | * \ |
237 | * There's absolutely nothing secure I can do with them. \ |
238 | */ \ |
239 | \ |
240 | assert(((void)"ECB must have at least one whole block to work with", \ |
241 | sz >= PRE##_BLKSZ)); \ |
242 | \ |
243 | /* --- Do the main chunk of decryption --- * \ |
244 | * \ |
245 | * This will do the whole lot if it's a whole number of blocks. \ |
246 | * Each block is just handed to the block cipher in turn. \ |
247 | */ \ |
248 | \ |
249 | while (sz >= 2 * PRE##_BLKSZ || sz == PRE##_BLKSZ) { \ |
250 | uint32 x[PRE##_BLKSZ / 4]; \ |
251 | BLKC_LOAD(PRE, x, s); \ |
252 | pre##_dblk(&ctx->ctx, x, x); \ |
253 | BLKC_STORE(PRE, d, x); \ |
254 | s += PRE##_BLKSZ; \ |
255 | d += PRE##_BLKSZ; \ |
256 | sz -= PRE##_BLKSZ; \ |
257 | } \ |
258 | \ |
259 | /* --- Do the tail-end block and bit-left-over --- * \ |
260 | * \ |
261 | * This isn't very efficient. That shouldn't matter much. \ |
262 | */ \ |
263 | \ |
264 | if (sz) { \ |
265 | uint32 x[PRE##_BLKSZ / 4]; \ |
266 | octet b[PRE##_BLKSZ]; \ |
267 | unsigned i; \ |
268 | \ |
269 | /* --- Let @sz@ be the size of the partial block --- */ \ |
270 | \ |
271 | sz -= PRE##_BLKSZ; \ |
272 | \ |
273 | /* --- First stage --- * \ |
274 | * \ |
275 | * Take the complete ciphertext block, and decrypt it. This block \ |
276 | * is carried over for the next encryption operation. \ |
277 | */ \ |
278 | \ |
279 | BLKC_LOAD(PRE, x, s); \ |
280 | pre##_dblk(&ctx->ctx, x, x); \ |
281 | BLKC_STORE(PRE, b, x); \ |
282 | \ |
283 | /* --- Second stage --- * \ |
284 | * \ |
285 | * The first few bytes are the partial plaintext block. Write that \ |
286 | * and replace with the partial ciphertext block. Then decrypt \ |
287 | * what's left as the complete plaintext. \ |
288 | */ \ |
289 | \ |
290 | s += PRE##_BLKSZ; \ |
291 | d += PRE##_BLKSZ; \ |
292 | for (i = 0; i < sz; i++) { \ |
293 | register octet y = s[i]; \ |
294 | d[i] = b[i]; \ |
295 | b[i] = y; \ |
296 | } \ |
297 | BLKC_LOAD(PRE, x, b); \ |
298 | pre##_dblk(&ctx->ctx, x, x); \ |
299 | BLKC_STORE(PRE, d - PRE##_BLKSZ, x); \ |
300 | } \ |
301 | \ |
302 | /* --- Done --- */ \ |
303 | \ |
304 | return; \ |
305 | } \ |
306 | \ |
307 | /* --- Generic cipher interface --- */ \ |
308 | \ |
309 | static const gcipher_ops gops; \ |
310 | \ |
311 | typedef struct gctx { \ |
312 | gcipher c; \ |
313 | pre##_ecbctx k; \ |
314 | } gctx; \ |
315 | \ |
316 | static gcipher *ginit(const void *k, size_t sz) \ |
317 | { \ |
318 | gctx *g = CREATE(gctx); \ |
319 | g->c.ops = &gops; \ |
320 | pre##_ecbinit(&g->k, k, sz, 0); \ |
321 | return (&g->c); \ |
322 | } \ |
323 | \ |
324 | static void gencrypt(gcipher *c, const void *s, void *t, size_t sz) \ |
325 | { \ |
326 | gctx *g = (gctx *)c; \ |
327 | pre##_ecbencrypt(&g->k, s, t, sz); \ |
328 | } \ |
329 | \ |
330 | static void gdecrypt(gcipher *c, const void *s, void *t, size_t sz) \ |
331 | { \ |
332 | gctx *g = (gctx *)c; \ |
333 | pre##_ecbdecrypt(&g->k, s, t, sz); \ |
334 | } \ |
335 | \ |
336 | static void gdestroy(gcipher *c) \ |
337 | { \ |
338 | gctx *g = (gctx *)c; \ |
339 | DESTROY(g); \ |
340 | } \ |
341 | \ |
342 | static const gcipher_ops gops = { \ |
343 | &pre##_ecb.b, \ |
344 | gencrypt, gdecrypt, gdestroy, 0, 0 \ |
345 | }; \ |
346 | \ |
347 | const gccipher pre##_ecb = { \ |
348 | { #pre "-ecb", PRE##_KEYSZ, PRE##_BLKSZ }, \ |
349 | ginit \ |
350 | }; \ |
351 | \ |
352 | ECB_TEST(PRE, pre) |
353 | |
354 | /*----- Test rig ----------------------------------------------------------*/ |
355 | |
356 | #ifdef TEST_RIG |
357 | |
358 | #include <stdio.h> |
359 | |
360 | #include "daftstory.h" |
361 | |
362 | /* --- @ECB_TEST@ --- * |
363 | * |
364 | * Arguments: @PRE@, @pre@ = prefixes for block cipher definitions |
365 | * |
366 | * Use: Standard test rig for ECB functions. |
367 | */ |
368 | |
369 | #define ECB_TEST(PRE, pre) \ |
370 | \ |
371 | /* --- Initial plaintext for the test --- */ \ |
372 | \ |
373 | static const octet text[] = TEXT; \ |
374 | \ |
375 | /* --- Key and IV to use --- */ \ |
376 | \ |
377 | static const octet key[] = KEY; \ |
378 | static const octet iv[] = IV; \ |
379 | \ |
380 | /* --- Buffers for encryption and decryption output --- */ \ |
381 | \ |
382 | static octet ct[sizeof(text)]; \ |
383 | static octet pt[sizeof(text)]; \ |
384 | \ |
385 | static void hexdump(const octet *p, size_t sz) \ |
386 | { \ |
387 | const octet *q = p + sz; \ |
388 | for (sz = 0; p < q; p++, sz++) { \ |
389 | printf("%02x", *p); \ |
390 | if ((sz + 1) % PRE##_BLKSZ == 0) \ |
391 | putchar(':'); \ |
392 | } \ |
393 | } \ |
394 | \ |
395 | int main(void) \ |
396 | { \ |
397 | size_t sz = 0, rest; \ |
398 | pre##_ecbctx ctx; \ |
399 | int status = 0; \ |
400 | int done = 0; \ |
401 | \ |
402 | size_t keysz = PRE##_KEYSZ ? \ |
403 | PRE##_KEYSZ : strlen((const char *)key); \ |
404 | \ |
405 | fputs(#pre "-ecb: ", stdout); \ |
406 | \ |
407 | pre##_ecbinit(&ctx, key, keysz, iv); \ |
408 | \ |
409 | while (sz <= sizeof(text)) { \ |
410 | rest = sizeof(text) - sz; \ |
411 | if ((sz != 0 && sz < PRE##_BLKSZ) || \ |
412 | (rest != 0 && rest < PRE##_BLKSZ)) \ |
413 | goto next; \ |
414 | memcpy(ct, text, sizeof(text)); \ |
415 | pre##_ecbencrypt(&ctx, ct, ct, sz); \ |
416 | pre##_ecbencrypt(&ctx, ct + sz, ct + sz, rest); \ |
417 | memcpy(pt, ct, sizeof(text)); \ |
418 | pre##_ecbdecrypt(&ctx, pt, pt, sz); \ |
419 | pre##_ecbdecrypt(&ctx, pt + sz, pt + sz, rest); \ |
420 | if (memcmp(pt, text, sizeof(text)) == 0) { \ |
421 | done++; \ |
422 | if (sizeof(text) < 40 || done % 8 == 0) \ |
423 | fputc('.', stdout); \ |
424 | if (done % 480 == 0) \ |
425 | fputs("\n\t", stdout); \ |
426 | fflush(stdout); \ |
427 | } else { \ |
428 | printf("\nError (sz = %lu)\n", (unsigned long)sz); \ |
429 | status = 1; \ |
430 | printf("\tplaintext = "); hexdump(text, sz); \ |
431 | printf(", "); hexdump(text + sz, rest); \ |
432 | fputc('\n', stdout); \ |
433 | printf("\tciphertext = "); hexdump(ct, sz); \ |
434 | printf(", "); hexdump(ct + sz, rest); \ |
435 | fputc('\n', stdout); \ |
436 | printf("\trecovered text = "); hexdump(pt, sz); \ |
437 | printf(", "); hexdump(pt + sz, rest); \ |
438 | fputc('\n', stdout); \ |
439 | fputc('\n', stdout); \ |
440 | } \ |
441 | next: \ |
442 | if (sz < 63) \ |
443 | sz++; \ |
444 | else \ |
445 | sz += 9; \ |
446 | } \ |
447 | \ |
448 | fputs(status ? " failed\n" : " ok\n", stdout); \ |
449 | return (status); \ |
450 | } |
451 | |
452 | #else |
453 | # define ECB_TEST(PRE, pre) |
454 | #endif |
455 | |
456 | /*----- That's all, folks -------------------------------------------------*/ |
457 | |
458 | #ifdef __cplusplus |
459 | } |
460 | #endif |
461 | |
462 | #endif |