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math/Makefile.am, symm/Makefile.am: Use `--no-install' on oddball tests.
[catacomb] / symm / counter-def.h
1 /* -*-c-*-
2 *
3 * Block cipher counter mode (or long cycle mode)
4 *
5 * (c) 2000 Straylight/Edgeware
6 */
7
8 /*----- Licensing notice --------------------------------------------------*
9 *
10 * This file is part of Catacomb.
11 *
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.
16 *
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.
21 *
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,
25 * MA 02111-1307, USA.
26 */
27
28 #ifndef CATACOMB_COUNTER_DEF_H
29 #define CATACOMB_COUNTER_DEF_H
30
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34
35 /*----- Header files ------------------------------------------------------*/
36
37 #include <stdarg.h>
38 #include <string.h>
39
40 #include <mLib/bits.h>
41 #include <mLib/sub.h>
42
43 #ifndef CATACOMB_ARENA_H
44 # include "arena.h"
45 #endif
46
47 #ifndef CATACOMB_BLKC_H
48 # include "blkc.h"
49 #endif
50
51 #ifndef CATACOMB_GCIPHER_H
52 # include "gcipher.h"
53 #endif
54
55 #ifndef CATACOMB_PARANOIA_H
56 # include "paranoia.h"
57 #endif
58
59 /*----- Macros ------------------------------------------------------------*/
60
61 /* --- @COUNTER_DEF@ --- *
62 *
63 * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher
64 *
65 * Use: Creates definitions for counter mode.
66 */
67
68 #define COUNTER_DEF(PRE, pre) COUNTER_DEFX(PRE, pre, #pre, #pre)
69
70 #define COUNTER_DEFX(PRE, pre, name, fname) \
71 \
72 /* --- @pre_countergetiv@ --- * \
73 * \
74 * Arguments: @const pre_counterctx *ctx@ = pointer to counter \
75 * context \
76 * @void *iv@ = pointer to output data block \
77 * \
78 * Returns: --- \
79 * \
80 * Use: Reads the currently set IV. Reading and setting an IV \
81 * is not transparent to the cipher. It will add a `step' \
82 * which must be matched by a similar operation during \
83 * decryption. \
84 */ \
85 \
86 void pre##_countergetiv(const pre##_counterctx *ctx, void *iv) \
87 { \
88 BLKC_STORE(PRE, iv, ctx->n); \
89 } \
90 \
91 /* --- @pre_countersetiv@ --- * \
92 * \
93 * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
94 * @cnost void *iv@ = pointer to IV to set \
95 * \
96 * Returns: --- \
97 * \
98 * Use: Sets the IV to use for subsequent encryption. \
99 */ \
100 \
101 void pre##_countersetiv(pre##_counterctx *ctx, const void *iv) \
102 { \
103 BLKC_LOAD(PRE, ctx->n, iv); \
104 ctx->off = PRE##_BLKSZ; \
105 } \
106 \
107 /* --- @pre_counterbdry@ --- * \
108 * \
109 * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
110 * \
111 * Returns: --- \
112 * \
113 * Use: Inserts a boundary during encryption. Successful \
114 * decryption must place a similar boundary. \
115 */ \
116 \
117 void pre##_counterbdry(pre##_counterctx *ctx) \
118 { \
119 BLKC_STEP(PRE, ctx->n); \
120 ctx->off = PRE##_BLKSZ; \
121 } \
122 \
123 /* --- @pre_countersetkey@ --- * \
124 * \
125 * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
126 * @const pre_ctx *k@ = pointer to cipher context \
127 * \
128 * Returns: --- \
129 * \
130 * Use: Sets the counter context to use a different cipher key. \
131 */ \
132 \
133 void pre##_countersetkey(pre##_counterctx *ctx, const pre##_ctx *k) \
134 { \
135 ctx->ctx = *k; \
136 } \
137 \
138 /* --- @pre_counterinit@ --- * \
139 * \
140 * Arguments: @pre_counterctx *ctx@ = pointer to cipher context \
141 * @const void *key@ = pointer to the key buffer \
142 * @size_t sz@ = size of the key \
143 * @const void *iv@ = pointer to initialization vector \
144 * \
145 * Returns: --- \
146 * \
147 * Use: Initializes a counter context ready for use. You \
148 * should ensure that the IV chosen is unique: reusing an \
149 * IV will compromise the security of the entire \
150 * plaintext. This is equivalent to calls to @pre_init@, \
151 * @pre_countersetkey@ and @pre_countersetiv@. \
152 */ \
153 \
154 void pre##_counterinit(pre##_counterctx *ctx, \
155 const void *key, size_t sz, \
156 const void *iv) \
157 { \
158 static const octet zero[PRE##_BLKSZ] = { 0 }; \
159 pre##_init(&ctx->ctx, key, sz); \
160 pre##_countersetiv(ctx, iv ? iv : zero); \
161 } \
162 \
163 /* --- @pre_counterencrypt@ --- * \
164 * \
165 * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
166 * @const void *src@ = pointer to source data \
167 * @void *dest@ = pointer to destination data \
168 * @size_t sz@ = size of block to be encrypted \
169 * \
170 * Returns: --- \
171 * \
172 * Use: Encrypts or decrypts a block with a block cipher in \
173 * counter mode: encryption and decryption are the same in \
174 * counter. The destination may be null to just churn the \
175 * feedback round for a bit. The source may be null to \
176 * use the cipher as a random data generator. \
177 */ \
178 \
179 void pre##_counterencrypt(pre##_counterctx *ctx, \
180 const void *src, void *dest, \
181 size_t sz) \
182 { \
183 const octet *s = src; \
184 octet *d = dest; \
185 unsigned off = ctx->off; \
186 \
187 /* --- Empty blocks are trivial --- */ \
188 \
189 if (!sz) \
190 return; \
191 \
192 /* --- If I can deal with the block from my buffer, do that --- */ \
193 \
194 if (sz < PRE##_BLKSZ - off) \
195 goto small; \
196 \
197 /* --- Finish off what's left in my buffer --- */ \
198 \
199 if (!d) \
200 sz -= PRE##_BLKSZ - off; \
201 else { \
202 while (off < PRE##_BLKSZ) { \
203 register octet x = s ? *s++ : 0; \
204 *d++ = ctx->buf[off++] ^ x; \
205 sz--; \
206 } \
207 } \
208 \
209 /* --- Main encryption loop --- */ \
210 \
211 { \
212 uint32 n[PRE##_BLKSZ / 4]; \
213 \
214 for (;;) { \
215 pre##_eblk(&ctx->ctx, ctx->n, n); \
216 BLKC_STEP(PRE, ctx->n); \
217 if (sz < PRE##_BLKSZ) \
218 break; \
219 if (d) { \
220 if (!s) \
221 BLKC_STORE(PRE, d, n); \
222 else { \
223 uint32 x[PRE##_BLKSZ / 4]; \
224 BLKC_LOAD(PRE, x, s); \
225 BLKC_XSTORE(PRE, d, n, x); \
226 s += PRE##_BLKSZ; \
227 } \
228 d += PRE##_BLKSZ; \
229 } \
230 sz -= PRE##_BLKSZ; \
231 } \
232 \
233 BLKC_STORE(PRE, ctx->buf, n); \
234 off = 0; \
235 } \
236 \
237 /* --- Tidying up the tail end --- */ \
238 \
239 if (sz) { \
240 small: \
241 if (!d) \
242 off += sz; \
243 else do { \
244 register octet x = s ? *s++ : 0; \
245 *d++ = ctx->buf[off++] ^ x; \
246 sz--; \
247 } while (sz); \
248 } \
249 \
250 /* --- Done --- */ \
251 \
252 ctx->off = off; \
253 return; \
254 } \
255 \
256 /* --- Generic cipher interface --- */ \
257 \
258 static const gcipher_ops gops; \
259 \
260 typedef struct gctx { \
261 gcipher c; \
262 pre##_counterctx k; \
263 } gctx; \
264 \
265 static gcipher *ginit(const void *k, size_t sz) \
266 { \
267 gctx *g = S_CREATE(gctx); \
268 g->c.ops = &gops; \
269 pre##_counterinit(&g->k, k, sz, 0); \
270 return (&g->c); \
271 } \
272 \
273 static void gencrypt(gcipher *c, const void *s, void *t, size_t sz) \
274 { \
275 gctx *g = (gctx *)c; \
276 pre##_counterencrypt(&g->k, s, t, sz); \
277 } \
278 \
279 static void gdestroy(gcipher *c) \
280 { \
281 gctx *g = (gctx *)c; \
282 BURN(*g); \
283 S_DESTROY(g); \
284 } \
285 \
286 static void gsetiv(gcipher *c, const void *iv) \
287 { \
288 gctx *g = (gctx *)c; \
289 pre##_countersetiv(&g->k, iv); \
290 } \
291 \
292 static void gbdry(gcipher *c) \
293 { \
294 gctx *g = (gctx *)c; \
295 pre##_counterbdry(&g->k); \
296 } \
297 \
298 static const gcipher_ops gops = { \
299 &pre##_counter, \
300 gencrypt, gencrypt, gdestroy, gsetiv, gbdry \
301 }; \
302 \
303 const gccipher pre##_counter = { \
304 name "-counter", pre##_keysz, PRE##_BLKSZ, \
305 ginit \
306 }; \
307 \
308 /* --- Generic random number generator interface --- */ \
309 \
310 typedef struct grctx { \
311 grand r; \
312 pre##_counterctx k; \
313 } grctx; \
314 \
315 static void grdestroy(grand *r) \
316 { \
317 grctx *g = (grctx *)r; \
318 BURN(*g); \
319 S_DESTROY(g); \
320 } \
321 \
322 static int grmisc(grand *r, unsigned op, ...) \
323 { \
324 grctx *g = (grctx *)r; \
325 va_list ap; \
326 int rc = 0; \
327 octet buf[PRE##_BLKSZ]; \
328 va_start(ap, op); \
329 \
330 switch (op) { \
331 case GRAND_CHECK: \
332 switch (va_arg(ap, unsigned)) { \
333 case GRAND_CHECK: \
334 case GRAND_SEEDINT: \
335 case GRAND_SEEDUINT32: \
336 case GRAND_SEEDBLOCK: \
337 case GRAND_SEEDRAND: \
338 rc = 1; \
339 break; \
340 default: \
341 rc = 0; \
342 break; \
343 } \
344 break; \
345 case GRAND_SEEDINT: \
346 BLKC_SET(PRE, g->k.n, va_arg(ap, unsigned)); \
347 g->k.off = PRE##_BLKSZ; \
348 break; \
349 case GRAND_SEEDUINT32: \
350 BLKC_SET(PRE, g->k.n, va_arg(ap, uint32)); \
351 g->k.off = PRE##_BLKSZ; \
352 break; \
353 case GRAND_SEEDBLOCK: { \
354 const void *p = va_arg(ap, const void *); \
355 size_t sz = va_arg(ap, size_t); \
356 if (sz < sizeof(buf)) { \
357 memset(buf, 0, sizeof(buf)); \
358 memcpy(buf, p, sz); \
359 p = buf; \
360 } \
361 pre##_countersetiv(&g->k, p); \
362 } break; \
363 case GRAND_SEEDRAND: { \
364 grand *rr = va_arg(ap, grand *); \
365 rr->ops->fill(rr, buf, sizeof(buf)); \
366 pre##_countersetiv(&g->k, buf); \
367 } break; \
368 default: \
369 GRAND_BADOP; \
370 break; \
371 } \
372 \
373 va_end(ap); \
374 return (rc); \
375 } \
376 \
377 static octet grbyte(grand *r) \
378 { \
379 grctx *g = (grctx *)r; \
380 octet o; \
381 pre##_counterencrypt(&g->k, 0, &o, 1); \
382 return (o); \
383 } \
384 \
385 static uint32 grword(grand *r) \
386 { \
387 grctx *g = (grctx *)r; \
388 octet b[4]; \
389 pre##_counterencrypt(&g->k, 0, b, sizeof(b)); \
390 return (LOAD32(b)); \
391 } \
392 \
393 static void grfill(grand *r, void *p, size_t sz) \
394 { \
395 grctx *g = (grctx *)r; \
396 pre##_counterencrypt(&g->k, 0, p, sz); \
397 } \
398 \
399 static const grand_ops grops = { \
400 name "-counter", \
401 GRAND_CRYPTO, 0, \
402 grmisc, grdestroy, \
403 grword, grbyte, grword, grand_defaultrange, grfill \
404 }; \
405 \
406 /* --- @pre_counterrand@ --- * \
407 * \
408 * Arguments: @const void *k@ = pointer to key material \
409 * @size_t sz@ = size of key material \
410 * \
411 * Returns: Pointer to generic random number generator interface. \
412 * \
413 * Use: Creates a random number interface wrapper around an \
414 * counter-mode block cipher. \
415 */ \
416 \
417 grand *pre##_counterrand(const void *k, size_t sz) \
418 { \
419 grctx *g = S_CREATE(grctx); \
420 g->r.ops = &grops; \
421 pre##_counterinit(&g->k, k, sz, 0); \
422 return (&g->r); \
423 } \
424 \
425 COUNTER_TESTX(PRE, pre, name, fname)
426
427 /*----- Test rig ----------------------------------------------------------*/
428
429 #define COUNTER_TEST(PRE, pre) COUNTER_TESTX(PRE, pre, #pre, #pre)
430
431 #ifdef TEST_RIG
432
433 #include <stdio.h>
434
435 #include "daftstory.h"
436
437 /* --- @COUNTER_TEST@ --- *
438 *
439 * Arguments: @PRE@, @pre@ = prefixes for block cipher definitions
440 *
441 * Use: Standard test rig for counter functions.
442 */
443
444 #define COUNTER_TESTX(PRE, pre, name, fname) \
445 \
446 /* --- Initial plaintext for the test --- */ \
447 \
448 static const octet text[] = TEXT; \
449 \
450 /* --- Key and IV to use --- */ \
451 \
452 static const octet key[] = KEY; \
453 static const octet iv[] = IV; \
454 \
455 /* --- Buffers for encryption and decryption output --- */ \
456 \
457 static octet ct[sizeof(text)]; \
458 static octet pt[sizeof(text)]; \
459 \
460 static void hexdump(const octet *p, size_t sz, size_t off) \
461 { \
462 const octet *q = p + sz; \
463 for (sz = 0; p < q; p++, sz++) { \
464 printf("%02x", *p); \
465 if ((off + sz + 1) % PRE##_BLKSZ == 0) \
466 putchar(':'); \
467 } \
468 } \
469 \
470 int main(void) \
471 { \
472 size_t sz = 0, rest; \
473 pre##_counterctx ctx; \
474 int status = 0; \
475 int done = 0; \
476 pre##_ctx k; \
477 \
478 size_t keysz = PRE##_KEYSZ ? \
479 PRE##_KEYSZ : strlen((const char *)key); \
480 \
481 fputs(name "-counter: ", stdout); \
482 \
483 pre##_init(&k, key, keysz); \
484 pre##_countersetkey(&ctx, &k); \
485 \
486 while (sz <= sizeof(text)) { \
487 rest = sizeof(text) - sz; \
488 memcpy(ct, text, sizeof(text)); \
489 pre##_countersetiv(&ctx, iv); \
490 pre##_counterencrypt(&ctx, ct, ct, sz); \
491 pre##_counterencrypt(&ctx, ct + sz, ct + sz, rest); \
492 memcpy(pt, ct, sizeof(text)); \
493 pre##_countersetiv(&ctx, iv); \
494 pre##_counterencrypt(&ctx, pt, pt, rest); \
495 pre##_counterencrypt(&ctx, pt + rest, pt + rest, sz); \
496 if (memcmp(pt, text, sizeof(text)) == 0) { \
497 done++; \
498 if (sizeof(text) < 40 || done % 8 == 0) \
499 fputc('.', stdout); \
500 if (done % 480 == 0) \
501 fputs("\n\t", stdout); \
502 fflush(stdout); \
503 } else { \
504 printf("\nError (sz = %lu)\n", (unsigned long)sz); \
505 status = 1; \
506 printf("\tplaintext = "); hexdump(text, sz, 0); \
507 printf(", "); hexdump(text + sz, rest, sz); \
508 fputc('\n', stdout); \
509 printf("\tciphertext = "); hexdump(ct, sz, 0); \
510 printf(", "); hexdump(ct + sz, rest, sz); \
511 fputc('\n', stdout); \
512 printf("\trecovered text = "); hexdump(pt, sz, 0); \
513 printf(", "); hexdump(pt + sz, rest, sz); \
514 fputc('\n', stdout); \
515 fputc('\n', stdout); \
516 } \
517 if (sz < 63) \
518 sz++; \
519 else \
520 sz += 9; \
521 } \
522 \
523 fputs(status ? " failed\n" : " ok\n", stdout); \
524 return (status); \
525 }
526
527 #else
528 # define COUNTER_TESTX(PRE, pre, name, fname)
529 #endif
530
531 /*----- That's all, folks -------------------------------------------------*/
532
533 #ifdef __cplusplus
534 }
535 #endif
536
537 #endif
Catacomb cryptographic library