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Fix bounds on workspace for Karatsuba operations.
[u/mdw/catacomb] / mp-arith.c
CommitLineData
d3409d5e 1/* -*-c-*-
2 *
dd22938e 3 * $Id: mp-arith.c,v 1.12 2002/10/09 00:36:03 mdw Exp $
d3409d5e 4 *
5 * Basic arithmetic on multiprecision integers
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: mp-arith.c,v $
dd22938e 33 * Revision 1.12 2002/10/09 00:36:03 mdw
34 * Fix bounds on workspace for Karatsuba operations.
35 *
f09e814a 36 * Revision 1.11 2002/10/06 22:52:50 mdw
37 * Pile of changes for supporting two's complement properly.
38 *
0f32e0f8 39 * Revision 1.10 2001/04/03 19:36:05 mdw
40 * Add some simple bitwise operations so that Perl can use them.
41 *
52cdaca9 42 * Revision 1.9 2000/10/08 15:48:35 mdw
43 * Rename Karatsuba constants now that we have @gfx_kmul@ too.
44 *
4b536f42 45 * Revision 1.8 2000/10/08 12:02:21 mdw
46 * Use @MP_EQ@ instead of @MP_CMP@.
47 *
f1713c63 48 * Revision 1.7 2000/06/22 19:02:53 mdw
49 * New function @mp_odd@ to extract powers of two from an integer. This is
50 * common code from the Rabin-Miller test, RSA key recovery and modular
51 * square-root extraction.
52 *
d34decd2 53 * Revision 1.6 2000/06/17 11:45:09 mdw
54 * Major memory management overhaul. Added arena support. Use the secure
55 * arena for secret integers. Replace and improve the MP management macros
56 * (e.g., replace MP_MODIFY by MP_DEST).
57 *
bba03f55 58 * Revision 1.5 1999/12/22 15:54:41 mdw
59 * Adjust Karatsuba parameters. Calculate destination size better.
60 *
8017495b 61 * Revision 1.4 1999/12/13 15:35:16 mdw
62 * Slightly different rules on memory allocation.
63 *
5bf74dea 64 * Revision 1.3 1999/12/11 10:57:43 mdw
65 * Karatsuba squaring algorithm.
66 *
ef5f4810 67 * Revision 1.2 1999/12/10 23:18:39 mdw
68 * Change interface for suggested destinations.
69 *
d3409d5e 70 * Revision 1.1 1999/11/17 18:02:16 mdw
71 * New multiprecision integer arithmetic suite.
72 *
73 */
74
75/*----- Header files ------------------------------------------------------*/
76
77#include "mp.h"
78
ef5f4810 79/*----- Macros ------------------------------------------------------------*/
80
81#define MAX(x, y) ((x) >= (y) ? (x) : (y))
82
d3409d5e 83/*----- Main code ---------------------------------------------------------*/
84
f09e814a 85/* --- @mp_lsl@, @mp_lsr@ --- *
d3409d5e 86 *
f09e814a 87 * Arguments: @mp *d@ = destination
88 * @mp *a@ = source
89 * @size_t n@ = number of bits to move
d3409d5e 90 *
f09e814a 91 * Returns: Result, @a@ shifted left or right by @n@.
d3409d5e 92 */
93
f09e814a 94mp *mp_lsl(mp *d, mp *a, size_t n)
d3409d5e 95{
f09e814a 96 MP_DEST(d, MP_LEN(a) + (n + MPW_BITS - 1) / MPW_BITS, a->f);
97 mpx_lsl(d->v, d->vl, a->v, a->vl, n);
98 d->f = a->f & (MP_NEG | MP_BURN);
99 MP_SHRINK(d);
100 return (d);
101}
d3409d5e 102
f09e814a 103mp *mp_lsr(mp *d, mp *a, size_t n)
104{
d34decd2 105 MP_DEST(d, MP_LEN(a), a->f);
f09e814a 106 mpx_lsr(d->v, d->vl, a->v, a->vl, n);
107 d->f = a->f & (MP_NEG | MP_BURN);
d3409d5e 108 MP_SHRINK(d);
109 return (d);
110}
111
f09e814a 112/* --- @mp_lsl2c@, @mp_lsr2c@ --- *
d3409d5e 113 *
114 * Arguments: @mp *d@ = destination
115 * @mp *a@ = source
f09e814a 116 * @size_t n@ = number of bits to move
d3409d5e 117 *
f09e814a 118 * Returns: Result, @a@ shifted left or right by @n@. Handles the
119 * pretence of sign-extension for negative numbers.
d3409d5e 120 */
121
f09e814a 122mp *mp_lsl2c(mp *d, mp *a, size_t n)
d3409d5e 123{
f09e814a 124 if (!(a->f & MP_NEG))
125 return (mp_lsl(d, a, n));
126 d = mp_not2c(d, a);
127 d = mp_lsl(d, d, n);
128 d = mp_not2c(d, d);
129 return (d);
130}
d3409d5e 131
f09e814a 132mp *mp_lsr2c(mp *d, mp *a, size_t n)
133{
134 if (!(a->f & MP_NEG))
135 return (mp_lsr(d, a, n));
136 d = mp_not2c(d, a);
137 d = mp_lsr(d, d, n);
138 d = mp_not2c(d, d);
139 return (d);
d3409d5e 140}
141
f09e814a 142/* --- @mp_testbit@ --- *
d3409d5e 143 *
f09e814a 144 * Arguments: @mp *x@ = a large integer
145 * @size_t n@ = which bit to test
d3409d5e 146 *
f09e814a 147 * Returns: Nonzero if the bit is set, zero if not.
d3409d5e 148 */
149
f09e814a 150int mp_testbit(mp *x, size_t n)
d3409d5e 151{
f09e814a 152 size_t o;
153 if (n > MPW_BITS * MP_LEN(x))
154 return (0);
155 o = n / MPW_BITS;
156 n %= MPW_BITS;
157 return ((x->v[o] >> n) & 1);
d3409d5e 158}
159
f09e814a 160/* --- @mp_testbit2c@ --- *
d3409d5e 161 *
f09e814a 162 * Arguments: @mp *x@ = a large integer
163 * @size_t n@ = which bit to test
d3409d5e 164 *
f09e814a 165 * Returns: Nonzero if the bit is set, zero if not. Fakes up two's
166 * complement representation.
d3409d5e 167 */
168
f09e814a 169int mp_testbit2c(mp *x, size_t n)
d3409d5e 170{
f09e814a 171 int r;
172 if (x->f & MP_NEG)
173 return (mp_testbit(x, n));
174 x = mp_not2c(MP_NEW, x);
175 r = !mp_testbit(x, n);
176 MP_DROP(x);
177 return (r);
d3409d5e 178}
179
4b536f42 180/* --- @mp_eq@ --- *
181 *
182 * Arguments: @const mp *a, *b@ = two numbers
183 *
184 * Returns: Nonzero if the numbers are equal.
185 */
186
187int mp_eq(const mp *a, const mp *b) { return (MP_EQ(a, b)); }
188
d3409d5e 189/* --- @mp_cmp@ --- *
190 *
191 * Arguments: @const mp *a, *b@ = two numbers
192 *
193 * Returns: Less than, equal to or greater than zero, according to
194 * whether @a@ is less than, equal to or greater than @b@.
195 */
196
197int mp_cmp(const mp *a, const mp *b)
198{
199 if (!((a->f ^ b->f) & MP_NEG))
200 return (mpx_ucmp(a->v, a->vl, b->v, b->vl));
201 else if (a->f & MP_NEG)
202 return (-1);
203 else
204 return (+1);
205}
206
f09e814a 207/* --- @mp_bitop@ --- *
0f32e0f8 208 *
209 * Arguments: @mp *d@ = destination
210 * @mp *a, *b@ = sources
211 *
f09e814a 212 * Returns: The result of the given bitwise operation. These functions
213 * don't handle negative numbers at all sensibly. For that, use
214 * the @...2c@ variants. The functions are named after the
215 * truth tables they generate:
216 *
217 * a: 0011
218 * b: 0101
219 * @mpx_bitXXXX@
0f32e0f8 220 */
221
f09e814a 222#define MP_BITBINOP(string) \
0f32e0f8 223 \
f09e814a 224mp *mp_bit##string(mp *d, mp *a, mp *b) \
0f32e0f8 225{ \
226 MP_DEST(d, MAX(MP_LEN(a), MP_LEN(b)), a->f | b->f); \
f09e814a 227 mpx_bit##string(d->v, d->vl, a->v, a->vl, b->v, b->vl); \
0f32e0f8 228 d->f = (a->f | b->f) & MP_BURN; \
229 MP_SHRINK(d); \
230 return (d); \
231}
232
f09e814a 233MPX_DOBIN(MP_BITBINOP)
234
235/* --- @mp_not@ --- *
236 *
237 * Arguments: @mp *d@ = destination
238 * @mp *a@ = source
239 *
240 * Returns: The bitwise complement of the source.
241 */
0f32e0f8 242
243mp *mp_not(mp *d, mp *a)
244{
245 MP_DEST(d, MP_LEN(a), a->f);
246 mpx_not(d->v, d->vl, a->v, a->vl);
247 d->f = a->f & MP_BURN;
248 MP_SHRINK(d);
249 return (d);
250}
251
f09e814a 252/* --- @mp_bitop2c@ --- *
253 *
254 * Arguments: @mp *d@ = destination
255 * @mp *a, *b@ = sources
256 *
257 * Returns: The result of the given bitwise operation. Negative numbers
258 * are treated as two's complement, sign-extended infinitely to
259 * the left. The functions are named after the truth tables
260 * they generate:
261 *
262 * a: 0011
263 * b: 0101
264 * @mpx_bitXXXX@
265 */
266
267/* --- How this actually works --- *
268 *
269 * The two arguments are inverted (with a sign-swap) if they're currently
270 * negative. This means that we end up using a different function (one which
271 * reinverts as we go) for the main operation. Also, if the sign would be
272 * negative at the end, we preinvert the output and then invert again with a
273 * sign-swap.
274 *
275 * Start with: wxyz WXYZ
276 * If @a@ negative: yzwx or YZWX
277 * If @b@ negative: xwzy XWZY
278 * If both negative: zyxw ZYXW
279 */
280
281#define MP_BIT2CBINOP(n, base, an, bn, abn, p_base, p_an, p_bn, p_abn) \
282 \
283mp *mp_bit##n##2c(mp *d, mp *a, mp *b) \
284{ \
285 if (!((a->f | b->f) & MP_NEG)) { /* Both positive */ \
286 d = mp_bit##base(d, a, b); \
287 p_base \
288 } else if (!(b->f & MP_NEG)) { /* Only @b@ positive */ \
289 MP_COPY(b); \
290 d = mp_not2c(d, a); \
291 d = mp_bit##an(d, d, b); \
292 MP_DROP(b); \
293 p_an \
294 } else if (!(a->f & MP_NEG)) { /* Only @a@ positive */ \
295 MP_COPY(a); \
296 d = mp_not2c(d, b); \
297 d = mp_bit##bn(d, a, d); \
298 MP_DROP(a); \
299 p_bn \
300 } else { /* Both negative */ \
301 mp *t = mp_not2c(MP_NEW, a); \
302 mp *d = mp_not2c(d, b); \
303 d = mp_bit##abn(d, t, d); \
304 MP_DROP(t); \
305 p_abn \
306 } \
307 return (d); \
308} \
309
310#define NEG d = mp_not2c(d, d);
311#define POS
312MP_BIT2CBINOP(0000, 0000, 0000, 0000, 0000, POS, POS, POS, POS)
313MP_BIT2CBINOP(0001, 0001, 0100, 0010, 0111, POS, POS, POS, NEG)
314MP_BIT2CBINOP(0010, 0010, 0111, 0001, 0100, POS, NEG, POS, POS)
315MP_BIT2CBINOP(0011, 0011, 0011, 0011, 0011, POS, NEG, POS, NEG)
316MP_BIT2CBINOP(0100, 0100, 0001, 0111, 0010, POS, POS, NEG, POS)
317MP_BIT2CBINOP(0101, 0101, 0101, 0101, 0101, POS, POS, NEG, NEG)
318MP_BIT2CBINOP(0110, 0110, 0110, 0110, 0110, POS, NEG, NEG, POS)
319MP_BIT2CBINOP(0111, 0111, 0010, 0100, 0001, POS, NEG, NEG, NEG)
320MP_BIT2CBINOP(1000, 0111, 0010, 0100, 0001, NEG, POS, POS, POS)
321MP_BIT2CBINOP(1001, 0110, 0110, 0110, 0110, NEG, POS, POS, NEG)
322MP_BIT2CBINOP(1010, 0101, 0101, 0101, 0101, NEG, NEG, POS, POS)
323MP_BIT2CBINOP(1011, 0100, 0001, 0111, 0010, NEG, NEG, POS, NEG)
324MP_BIT2CBINOP(1100, 0011, 0011, 0011, 0011, NEG, POS, NEG, POS)
325MP_BIT2CBINOP(1101, 0010, 0111, 0001, 0100, NEG, POS, NEG, NEG)
326MP_BIT2CBINOP(1110, 0001, 0100, 0010, 0111, NEG, NEG, NEG, POS)
327MP_BIT2CBINOP(1111, 0000, 0000, 0000, 0000, NEG, NEG, NEG, NEG)
328#undef NEG
329#undef POS
330
331/* --- @mp_not2c@ --- *
332 *
333 * Arguments: @mp *d@ = destination
334 * @mp *a@ = source
335 *
336 * Returns: The sign-extended complement of the argument.
337 */
338
339mp *mp_not2c(mp *d, mp *a)
340{
341 mpw one = 1;
342
343 MP_DEST(d, MP_LEN(a) + 1, a->f);
344 if (d == a) {
345 if (a->f & MP_NEG)
346 MPX_USUBN(d->v, d->vl, 1);
347 else
348 MPX_UADDN(d->v, d->vl, 1);
349 } else {
350 if (a->f & MP_NEG)
351 mpx_usub(d->v, d->vl, a->v, a->vl, &one, &one + 1);
352 else
353 mpx_uadd(d->v, d->vl, a->v, a->vl, &one, &one + 1);
354 }
355 d->f = (a->f & (MP_NEG | MP_BURN)) ^ MP_NEG;
356 MP_SHRINK(d);
357 return (d);
358}
359
d3409d5e 360/* --- @mp_add@ --- *
361 *
362 * Arguments: @mp *d@ = destination
ef5f4810 363 * @mp *a, *b@ = sources
d3409d5e 364 *
365 * Returns: Result, @a@ added to @b@.
366 */
367
ef5f4810 368mp *mp_add(mp *d, mp *a, mp *b)
d3409d5e 369{
d34decd2 370 MP_DEST(d, MAX(MP_LEN(a), MP_LEN(b)) + 1, a->f | b->f);
d3409d5e 371 if (!((a->f ^ b->f) & MP_NEG))
372 mpx_uadd(d->v, d->vl, a->v, a->vl, b->v, b->vl);
373 else {
374 if (MPX_UCMP(a->v, a->vl, <, b->v, b->vl)) {
ef5f4810 375 mp *t = a; a = b; b = t;
d3409d5e 376 }
377 mpx_usub(d->v, d->vl, a->v, a->vl, b->v, b->vl);
378 }
379 d->f = ((a->f | b->f) & MP_BURN) | (a->f & MP_NEG);
380 MP_SHRINK(d);
381 return (d);
382}
383
384/* --- @mp_sub@ --- *
385 *
386 * Arguments: @mp *d@ = destination
ef5f4810 387 * @mp *a, *b@ = sources
d3409d5e 388 *
389 * Returns: Result, @b@ subtracted from @a@.
390 */
391
ef5f4810 392mp *mp_sub(mp *d, mp *a, mp *b)
d3409d5e 393{
394 unsigned sgn = 0;
d34decd2 395 MP_DEST(d, MAX(MP_LEN(a), MP_LEN(b)) + 1, a->f | b->f);
d3409d5e 396 if ((a->f ^ b->f) & MP_NEG)
397 mpx_uadd(d->v, d->vl, a->v, a->vl, b->v, b->vl);
398 else {
399 if (MPX_UCMP(a->v, a->vl, <, b->v, b->vl)) {
ef5f4810 400 mp *t = a; a = b; b = t;
d3409d5e 401 sgn = MP_NEG;
402 }
403 mpx_usub(d->v, d->vl, a->v, a->vl, b->v, b->vl);
404 }
405 d->f = ((a->f | b->f) & MP_BURN) | ((a->f ^ sgn) & MP_NEG);
406 MP_SHRINK(d);
407 return (d);
408}
409
410/* --- @mp_mul@ --- *
411 *
412 * Arguments: @mp *d@ = destination
ef5f4810 413 * @mp *a, *b@ = sources
d3409d5e 414 *
415 * Returns: Result, @a@ multiplied by @b@.
416 */
417
ef5f4810 418mp *mp_mul(mp *d, mp *a, mp *b)
d3409d5e 419{
ef5f4810 420 a = MP_COPY(a);
421 b = MP_COPY(b);
422
52cdaca9 423 if (MP_LEN(a) <= MPK_THRESH || MP_LEN(b) <= MPK_THRESH) {
d34decd2 424 MP_DEST(d, MP_LEN(a) + MP_LEN(b), a->f | b->f | MP_UNDEF);
ef5f4810 425 mpx_umul(d->v, d->vl, a->v, a->vl, b->v, b->vl);
8017495b 426 } else {
dd22938e 427 size_t m = MAX(MP_LEN(a), MP_LEN(b));
ef5f4810 428 mpw *s;
dd22938e 429 MP_DEST(d, 3 * m, a->f | b->f | MP_UNDEF);
430 s = mpalloc(d->a, 5 * m);
431 mpx_kmul(d->v, d->vl, a->v, a->vl, b->v, b->vl, s, s + 5 * m);
d34decd2 432 mpfree(d->a, s);
ef5f4810 433 }
434
d3409d5e 435 d->f = ((a->f | b->f) & MP_BURN) | ((a->f ^ b->f) & MP_NEG);
436 MP_SHRINK(d);
ef5f4810 437 MP_DROP(a);
438 MP_DROP(b);
d3409d5e 439 return (d);
440}
441
442/* --- @mp_sqr@ --- *
443 *
444 * Arguments: @mp *d@ = destination
ef5f4810 445 * @mp *a@ = source
d3409d5e 446 *
447 * Returns: Result, @a@ squared.
448 */
449
ef5f4810 450mp *mp_sqr(mp *d, mp *a)
d3409d5e 451{
ef5f4810 452 size_t m = MP_LEN(a);
453
454 a = MP_COPY(a);
52cdaca9 455 if (m > MPK_THRESH) {
ef5f4810 456 mpw *s;
dd22938e 457 MP_DEST(d, 3 * m, a->f | MP_UNDEF);
458 s = mpalloc(d->a, 5 * m);
459 mpx_ksqr(d->v, d->vl, a->v, a->vl, s, s + 5 * m);
d34decd2 460 mpfree(d->a, s);
dd22938e 461 } else {
462 MP_DEST(d, 2 * m + 2, a->f | MP_UNDEF);
ef5f4810 463 mpx_usqr(d->v, d->vl, a->v, a->vl);
dd22938e 464 }
d3409d5e 465 d->f = a->f & MP_BURN;
466 MP_SHRINK(d);
ef5f4810 467 MP_DROP(a);
d3409d5e 468 return (d);
469}
470
471/* --- @mp_div@ --- *
472 *
473 * Arguments: @mp **qq, **rr@ = destination, quotient and remainder
ef5f4810 474 * @mp *a, *b@ = sources
d3409d5e 475 *
476 * Use: Calculates the quotient and remainder when @a@ is divided by
477 * @b@. The destinations @*qq@ and @*rr@ must be distinct.
478 * Either of @qq@ or @rr@ may be null to indicate that the
479 * result is irrelevant. (Discarding both results is silly.)
480 * There is a performance advantage if @a == *rr@.
481 *
482 * The behaviour when @a@ and @b@ have the same sign is
483 * straightforward. When the signs differ, this implementation
484 * chooses @r@ to have the same sign as @b@, rather than the
485 * more normal choice that the remainder has the same sign as
486 * the dividend. This makes modular arithmetic a little more
487 * straightforward.
488 */
489
ef5f4810 490void mp_div(mp **qq, mp **rr, mp *a, mp *b)
d3409d5e 491 {
492 mp *r = rr ? *rr : MP_NEW;
493 mp *q = qq ? *qq : MP_NEW;
494 mpw *sv, *svl;
495
d3409d5e 496 /* --- Set the remainder up right --- *
497 *
498 * Just in case the divisor is larger, be able to cope with this. It's not
499 * important in @mpx_udiv@, but it is here because of the sign correction.
500 */
501
d34decd2 502 b = MP_COPY(b);
503 a = MP_COPY(a);
504 if (r)
505 MP_DROP(r);
506 r = a;
507 MP_DEST(r, MP_LEN(a) + 2, a->f | b->f);
d3409d5e 508
509 /* --- Fix up the quotient too --- */
510
d34decd2 511 r = MP_COPY(r);
512 MP_DEST(q, MP_LEN(r), r->f | MP_UNDEF);
513 MP_DROP(r);
514
515 /* --- Set up some temporary workspace --- */
516
517 {
518 size_t rq = MP_LEN(b) + 1;
519 sv = mpalloc(r->a, rq);
520 svl = sv + rq;
521 }
d3409d5e 522
523 /* --- Perform the calculation --- */
524
525 mpx_udiv(q->v, q->vl, r->v, r->vl, b->v, b->vl, sv, svl);
526
527 /* --- Sort out the sign of the results --- *
528 *
529 * If the signs of the arguments differ, and the remainder is nonzero, I
530 * must add one to the absolute value of the quotient and subtract the
531 * remainder from @b@.
532 */
533
d34decd2 534 q->f = ((r->f | b->f) & MP_BURN) | ((r->f ^ b->f) & MP_NEG);
d3409d5e 535 if (q->f & MP_NEG) {
ef5f4810 536 mpw *v;
537 for (v = r->v; v < r->vl; v++) {
d3409d5e 538 if (*v) {
539 MPX_UADDN(q->v, q->vl, 1);
540 mpx_usub(r->v, r->vl, b->v, b->vl, r->v, r->vl);
541 break;
542 }
543 }
544 }
545
d34decd2 546 r->f = ((r->f | b->f) & MP_BURN) | (b->f & MP_NEG);
d3409d5e 547
548 /* --- Store the return values --- */
549
d34decd2 550 mpfree(r->a, sv);
551 MP_DROP(b);
552
d3409d5e 553 if (!qq)
554 MP_DROP(q);
555 else {
556 MP_SHRINK(q);
557 *qq = q;
558 }
559
560 if (!rr)
561 MP_DROP(r);
562 else {
563 MP_SHRINK(r);
564 *rr = r;
565 }
d3409d5e 566}
567
f1713c63 568/* --- @mp_odd@ --- *
569 *
570 * Arguments: @mp *d@ = pointer to destination integer
571 * @mp *m@ = pointer to source integer
572 * @size_t *s@ = where to store the power of 2
573 *
574 * Returns: An odd integer integer %$t$% such that %$m = 2^s t$%.
575 *
576 * Use: Computes a power of two and an odd integer which, when
577 * multiplied, give a specified result. This sort of thing is
578 * useful in number theory quite often.
579 */
580
581mp *mp_odd(mp *d, mp *m, size_t *s)
582{
583 size_t ss = 0;
584 const mpw *v, *vl;
585
586 v = m->v;
587 vl = m->vl;
588 for (; !*v && v < vl; v++)
589 ss += MPW_BITS;
590 if (v >= vl)
591 ss = 0;
592 else {
593 mpw x = *v;
594 mpw mask = MPW_MAX;
595 unsigned z = MPW_BITS / 2;
596
597 while (z) {
598 mask >>= z;
599 if (!(x & mask)) {
600 x >>= z;
601 ss += z;
602 }
603 z >>= 1;
604 }
605 }
606
607 *s = ss;
608 return (mp_lsr(d, m, ss));
609}
610
d3409d5e 611/*----- Test rig ----------------------------------------------------------*/
612
613#ifdef TEST_RIG
614
615static int verify(const char *op, mp *expect, mp *result, mp *a, mp *b)
616{
4b536f42 617 if (!MP_EQ(expect, result)) {
d3409d5e 618 fprintf(stderr, "\n*** %s failed", op);
619 fputs("\n*** a = ", stderr); mp_writefile(a, stderr, 10);
620 fputs("\n*** b = ", stderr); mp_writefile(b, stderr, 10);
621 fputs("\n*** result = ", stderr); mp_writefile(result, stderr, 10);
622 fputs("\n*** expect = ", stderr); mp_writefile(expect, stderr, 10);
623 fputc('\n', stderr);
624 return (0);
625 }
626 return (1);
627}
628
629#define RIG(name, op) \
ef5f4810 630 static int t##name(dstr *v) \
d3409d5e 631 { \
632 mp *a = *(mp **)v[0].buf; \
633 mpw n = *(int *)v[1].buf; \
634 mp b; \
635 mp *r = *(mp **)v[2].buf; \
636 mp *c = op(MP_NEW, a, n); \
637 int ok; \
638 mp_build(&b, &n, &n + 1); \
639 ok = verify(#name, r, c, a, &b); \
640 mp_drop(a); mp_drop(c); mp_drop(r); \
ef5f4810 641 assert(mparena_count(MPARENA_GLOBAL) == 0); \
d3409d5e 642 return (ok); \
643 }
644
645RIG(lsl, mp_lsl)
646RIG(lsr, mp_lsr)
f09e814a 647RIG(lsl2c, mp_lsl2c)
648RIG(lsr2c, mp_lsr2c)
d3409d5e 649
650#undef RIG
651
652#define RIG(name, op) \
ef5f4810 653 static int t##name(dstr *v) \
d3409d5e 654 { \
655 mp *a = *(mp **)v[0].buf; \
656 mp *b = *(mp **)v[1].buf; \
657 mp *r = *(mp **)v[2].buf; \
658 mp *c = op(MP_NEW, a, b); \
659 int ok = verify(#name, r, c, a, b); \
660 mp_drop(a); mp_drop(b); mp_drop(c); mp_drop(r); \
ef5f4810 661 assert(mparena_count(MPARENA_GLOBAL) == 0); \
d3409d5e 662 return (ok); \
663 }
664
665RIG(add, mp_add)
666RIG(sub, mp_sub)
667RIG(mul, mp_mul)
668
669#undef RIG
670
671static int tdiv(dstr *v)
672{
673 mp *a = *(mp **)v[0].buf;
674 mp *b = *(mp **)v[1].buf;
675 mp *q = *(mp **)v[2].buf;
676 mp *r = *(mp **)v[3].buf;
677 mp *c = MP_NEW, *d = MP_NEW;
678 int ok = 1;
679 mp_div(&c, &d, a, b);
680 ok &= verify("div(quotient)", q, c, a, b);
681 ok &= verify("div(remainder)", r, d, a, b);
682 mp_drop(a); mp_drop(b); mp_drop(c); mp_drop(d); mp_drop(r); mp_drop(q);
ef5f4810 683 assert(mparena_count(MPARENA_GLOBAL) == 0);
d3409d5e 684 return (ok);
685}
686
f09e814a 687static int tbin(dstr *v)
688{
689 static mp *(*fn[])(mp *, mp *, mp *) = {
690#define DO(string) mp_bit##string##2c,
691MPX_DOBIN(DO)
692#undef DO
693 };
694 int ok = 1;
695 unsigned op = 0;
696 mp *a = *(mp **)v[1].buf;
697 mp *b = *(mp **)v[2].buf;
698 mp *r = *(mp **)v[3].buf;
699 mp *c;
700
701 if (strcmp(v[0].buf, "and") == 0) op = 1;
702 else if (strcmp(v[0].buf, "or") == 0) op = 7;
703 else if (strcmp(v[0].buf, "nand") == 0) op = 14;
704 else if (strcmp(v[0].buf, "nor") == 0) op = 8;
705 else if (strcmp(v[0].buf, "xor") == 0) op = 6;
706 else {
707 char *p = v[0].buf;
708 while (*p) {
709 op <<= 1;
710 if (*p++ == '1')
711 op |= 1;
712 }
713 }
714
715 c = fn[op](MP_NEW, a, b);
716 ok = verify(v[0].buf, r, c, a, b);
717 mp_drop(a); mp_drop(b); mp_drop(r); mp_drop(c);
718 assert(mparena_count(MPARENA_GLOBAL) == 0);
719 return (ok);
720}
721
f1713c63 722static int todd(dstr *v)
723{
724 mp *a = *(mp **)v[0].buf;
725 size_t rs = *(uint32 *)v[1].buf;
726 mp *rt = *(mp **)v[2].buf;
727 int ok = 1;
728 mp *t;
729 size_t s;
730 t = mp_odd(MP_NEW, a, &s);
4b536f42 731 if (s != rs || !MP_EQ(t, rt)) {
f1713c63 732 ok = 0;
733 fprintf(stderr, "\n*** odd failed");
734 fputs("\n*** a = ", stderr); mp_writefile(a, stderr, 10);
735 fprintf(stderr, "\n*** s = %lu", (unsigned long)s);
736 fputs("\n*** t = ", stderr); mp_writefile(t, stderr, 10);
737 fprintf(stderr, "\n*** rs = %lu", (unsigned long)rs);
738 fputs("\n*** rt = ", stderr); mp_writefile(rt, stderr, 10);
739 fputc('\n', stderr);
740 }
741 mp_drop(a);
742 mp_drop(rt);
743 mp_drop(t);
744 return (ok);
745}
746
d3409d5e 747static test_chunk tests[] = {
f09e814a 748 { "lsl", tlsl, { &type_mp, &type_int, &type_mp, 0 } },
749 { "lsr", tlsr, { &type_mp, &type_int, &type_mp, 0 } },
750 { "lsl2c", tlsl2c, { &type_mp, &type_int, &type_mp, 0 } },
751 { "lsr2c", tlsr2c, { &type_mp, &type_int, &type_mp, 0 } },
d3409d5e 752 { "add", tadd, { &type_mp, &type_mp, &type_mp, 0 } },
753 { "sub", tsub, { &type_mp, &type_mp, &type_mp, 0 } },
754 { "mul", tmul, { &type_mp, &type_mp, &type_mp, 0 } },
755 { "div", tdiv, { &type_mp, &type_mp, &type_mp, &type_mp, 0 } },
f09e814a 756 { "bin2c", tbin, { &type_string, &type_mp, &type_mp, &type_mp, 0 } },
f1713c63 757 { "odd", todd, { &type_mp, &type_uint32, &type_mp, 0 } },
d3409d5e 758 { 0, 0, { 0 } },
759};
760
761int main(int argc, char *argv[])
762{
763 sub_init();
764 test_run(argc, argv, tests, SRCDIR "/tests/mp");
765 return (0);
766}
767
768#endif
769
770/*----- That's all, folks -------------------------------------------------*/
Catacomb cryptographic library (downstream of http://git.distorted.org.uk/~mdw/catacomb/)