diff options
Diffstat (limited to 'src/lib/libcrypto/ec/ecp_smpl.c')
-rw-r--r-- | src/lib/libcrypto/ec/ecp_smpl.c | 1360 |
1 files changed, 0 insertions, 1360 deletions
diff --git a/src/lib/libcrypto/ec/ecp_smpl.c b/src/lib/libcrypto/ec/ecp_smpl.c deleted file mode 100644 index 7cbb321f9a..0000000000 --- a/src/lib/libcrypto/ec/ecp_smpl.c +++ /dev/null | |||
@@ -1,1360 +0,0 @@ | |||
1 | /* crypto/ec/ecp_smpl.c */ | ||
2 | /* Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de> | ||
3 | * for the OpenSSL project. | ||
4 | * Includes code written by Bodo Moeller for the OpenSSL project. | ||
5 | */ | ||
6 | /* ==================================================================== | ||
7 | * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. | ||
8 | * | ||
9 | * Redistribution and use in source and binary forms, with or without | ||
10 | * modification, are permitted provided that the following conditions | ||
11 | * are met: | ||
12 | * | ||
13 | * 1. Redistributions of source code must retain the above copyright | ||
14 | * notice, this list of conditions and the following disclaimer. | ||
15 | * | ||
16 | * 2. Redistributions in binary form must reproduce the above copyright | ||
17 | * notice, this list of conditions and the following disclaimer in | ||
18 | * the documentation and/or other materials provided with the | ||
19 | * distribution. | ||
20 | * | ||
21 | * 3. All advertising materials mentioning features or use of this | ||
22 | * software must display the following acknowledgment: | ||
23 | * "This product includes software developed by the OpenSSL Project | ||
24 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" | ||
25 | * | ||
26 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to | ||
27 | * endorse or promote products derived from this software without | ||
28 | * prior written permission. For written permission, please contact | ||
29 | * openssl-core@openssl.org. | ||
30 | * | ||
31 | * 5. Products derived from this software may not be called "OpenSSL" | ||
32 | * nor may "OpenSSL" appear in their names without prior written | ||
33 | * permission of the OpenSSL Project. | ||
34 | * | ||
35 | * 6. Redistributions of any form whatsoever must retain the following | ||
36 | * acknowledgment: | ||
37 | * "This product includes software developed by the OpenSSL Project | ||
38 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" | ||
39 | * | ||
40 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY | ||
41 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
42 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | ||
43 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR | ||
44 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | ||
45 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
46 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | ||
47 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
48 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | ||
49 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
50 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED | ||
51 | * OF THE POSSIBILITY OF SUCH DAMAGE. | ||
52 | * ==================================================================== | ||
53 | * | ||
54 | * This product includes cryptographic software written by Eric Young | ||
55 | * (eay@cryptsoft.com). This product includes software written by Tim | ||
56 | * Hudson (tjh@cryptsoft.com). | ||
57 | * | ||
58 | */ | ||
59 | /* ==================================================================== | ||
60 | * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. | ||
61 | * Portions of this software developed by SUN MICROSYSTEMS, INC., | ||
62 | * and contributed to the OpenSSL project. | ||
63 | */ | ||
64 | |||
65 | #include <openssl/err.h> | ||
66 | #include <openssl/symhacks.h> | ||
67 | |||
68 | #ifdef OPENSSL_FIPS | ||
69 | #include <openssl/fips.h> | ||
70 | #endif | ||
71 | |||
72 | #include "ec_lcl.h" | ||
73 | |||
74 | const EC_METHOD *EC_GFp_simple_method(void) | ||
75 | { | ||
76 | #ifdef OPENSSL_FIPS | ||
77 | return fips_ec_gfp_simple_method(); | ||
78 | #else | ||
79 | static const EC_METHOD ret = { | ||
80 | EC_FLAGS_DEFAULT_OCT, | ||
81 | NID_X9_62_prime_field, | ||
82 | ec_GFp_simple_group_init, | ||
83 | ec_GFp_simple_group_finish, | ||
84 | ec_GFp_simple_group_clear_finish, | ||
85 | ec_GFp_simple_group_copy, | ||
86 | ec_GFp_simple_group_set_curve, | ||
87 | ec_GFp_simple_group_get_curve, | ||
88 | ec_GFp_simple_group_get_degree, | ||
89 | ec_GFp_simple_group_check_discriminant, | ||
90 | ec_GFp_simple_point_init, | ||
91 | ec_GFp_simple_point_finish, | ||
92 | ec_GFp_simple_point_clear_finish, | ||
93 | ec_GFp_simple_point_copy, | ||
94 | ec_GFp_simple_point_set_to_infinity, | ||
95 | ec_GFp_simple_set_Jprojective_coordinates_GFp, | ||
96 | ec_GFp_simple_get_Jprojective_coordinates_GFp, | ||
97 | ec_GFp_simple_point_set_affine_coordinates, | ||
98 | ec_GFp_simple_point_get_affine_coordinates, | ||
99 | 0,0,0, | ||
100 | ec_GFp_simple_add, | ||
101 | ec_GFp_simple_dbl, | ||
102 | ec_GFp_simple_invert, | ||
103 | ec_GFp_simple_is_at_infinity, | ||
104 | ec_GFp_simple_is_on_curve, | ||
105 | ec_GFp_simple_cmp, | ||
106 | ec_GFp_simple_make_affine, | ||
107 | ec_GFp_simple_points_make_affine, | ||
108 | 0 /* mul */, | ||
109 | 0 /* precompute_mult */, | ||
110 | 0 /* have_precompute_mult */, | ||
111 | ec_GFp_simple_field_mul, | ||
112 | ec_GFp_simple_field_sqr, | ||
113 | 0 /* field_div */, | ||
114 | 0 /* field_encode */, | ||
115 | 0 /* field_decode */, | ||
116 | 0 /* field_set_to_one */ }; | ||
117 | |||
118 | return &ret; | ||
119 | #endif | ||
120 | } | ||
121 | |||
122 | |||
123 | /* Most method functions in this file are designed to work with | ||
124 | * non-trivial representations of field elements if necessary | ||
125 | * (see ecp_mont.c): while standard modular addition and subtraction | ||
126 | * are used, the field_mul and field_sqr methods will be used for | ||
127 | * multiplication, and field_encode and field_decode (if defined) | ||
128 | * will be used for converting between representations. | ||
129 | |||
130 | * Functions ec_GFp_simple_points_make_affine() and | ||
131 | * ec_GFp_simple_point_get_affine_coordinates() specifically assume | ||
132 | * that if a non-trivial representation is used, it is a Montgomery | ||
133 | * representation (i.e. 'encoding' means multiplying by some factor R). | ||
134 | */ | ||
135 | |||
136 | |||
137 | int ec_GFp_simple_group_init(EC_GROUP *group) | ||
138 | { | ||
139 | BN_init(&group->field); | ||
140 | BN_init(&group->a); | ||
141 | BN_init(&group->b); | ||
142 | group->a_is_minus3 = 0; | ||
143 | return 1; | ||
144 | } | ||
145 | |||
146 | |||
147 | void ec_GFp_simple_group_finish(EC_GROUP *group) | ||
148 | { | ||
149 | BN_free(&group->field); | ||
150 | BN_free(&group->a); | ||
151 | BN_free(&group->b); | ||
152 | } | ||
153 | |||
154 | |||
155 | void ec_GFp_simple_group_clear_finish(EC_GROUP *group) | ||
156 | { | ||
157 | BN_clear_free(&group->field); | ||
158 | BN_clear_free(&group->a); | ||
159 | BN_clear_free(&group->b); | ||
160 | } | ||
161 | |||
162 | |||
163 | int ec_GFp_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src) | ||
164 | { | ||
165 | if (!BN_copy(&dest->field, &src->field)) return 0; | ||
166 | if (!BN_copy(&dest->a, &src->a)) return 0; | ||
167 | if (!BN_copy(&dest->b, &src->b)) return 0; | ||
168 | |||
169 | dest->a_is_minus3 = src->a_is_minus3; | ||
170 | |||
171 | return 1; | ||
172 | } | ||
173 | |||
174 | |||
175 | int ec_GFp_simple_group_set_curve(EC_GROUP *group, | ||
176 | const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) | ||
177 | { | ||
178 | int ret = 0; | ||
179 | BN_CTX *new_ctx = NULL; | ||
180 | BIGNUM *tmp_a; | ||
181 | |||
182 | /* p must be a prime > 3 */ | ||
183 | if (BN_num_bits(p) <= 2 || !BN_is_odd(p)) | ||
184 | { | ||
185 | ECerr(EC_F_EC_GFP_SIMPLE_GROUP_SET_CURVE, EC_R_INVALID_FIELD); | ||
186 | return 0; | ||
187 | } | ||
188 | |||
189 | if (ctx == NULL) | ||
190 | { | ||
191 | ctx = new_ctx = BN_CTX_new(); | ||
192 | if (ctx == NULL) | ||
193 | return 0; | ||
194 | } | ||
195 | |||
196 | BN_CTX_start(ctx); | ||
197 | tmp_a = BN_CTX_get(ctx); | ||
198 | if (tmp_a == NULL) goto err; | ||
199 | |||
200 | /* group->field */ | ||
201 | if (!BN_copy(&group->field, p)) goto err; | ||
202 | BN_set_negative(&group->field, 0); | ||
203 | |||
204 | /* group->a */ | ||
205 | if (!BN_nnmod(tmp_a, a, p, ctx)) goto err; | ||
206 | if (group->meth->field_encode) | ||
207 | { if (!group->meth->field_encode(group, &group->a, tmp_a, ctx)) goto err; } | ||
208 | else | ||
209 | if (!BN_copy(&group->a, tmp_a)) goto err; | ||
210 | |||
211 | /* group->b */ | ||
212 | if (!BN_nnmod(&group->b, b, p, ctx)) goto err; | ||
213 | if (group->meth->field_encode) | ||
214 | if (!group->meth->field_encode(group, &group->b, &group->b, ctx)) goto err; | ||
215 | |||
216 | /* group->a_is_minus3 */ | ||
217 | if (!BN_add_word(tmp_a, 3)) goto err; | ||
218 | group->a_is_minus3 = (0 == BN_cmp(tmp_a, &group->field)); | ||
219 | |||
220 | ret = 1; | ||
221 | |||
222 | err: | ||
223 | BN_CTX_end(ctx); | ||
224 | if (new_ctx != NULL) | ||
225 | BN_CTX_free(new_ctx); | ||
226 | return ret; | ||
227 | } | ||
228 | |||
229 | |||
230 | int ec_GFp_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b, BN_CTX *ctx) | ||
231 | { | ||
232 | int ret = 0; | ||
233 | BN_CTX *new_ctx = NULL; | ||
234 | |||
235 | if (p != NULL) | ||
236 | { | ||
237 | if (!BN_copy(p, &group->field)) return 0; | ||
238 | } | ||
239 | |||
240 | if (a != NULL || b != NULL) | ||
241 | { | ||
242 | if (group->meth->field_decode) | ||
243 | { | ||
244 | if (ctx == NULL) | ||
245 | { | ||
246 | ctx = new_ctx = BN_CTX_new(); | ||
247 | if (ctx == NULL) | ||
248 | return 0; | ||
249 | } | ||
250 | if (a != NULL) | ||
251 | { | ||
252 | if (!group->meth->field_decode(group, a, &group->a, ctx)) goto err; | ||
253 | } | ||
254 | if (b != NULL) | ||
255 | { | ||
256 | if (!group->meth->field_decode(group, b, &group->b, ctx)) goto err; | ||
257 | } | ||
258 | } | ||
259 | else | ||
260 | { | ||
261 | if (a != NULL) | ||
262 | { | ||
263 | if (!BN_copy(a, &group->a)) goto err; | ||
264 | } | ||
265 | if (b != NULL) | ||
266 | { | ||
267 | if (!BN_copy(b, &group->b)) goto err; | ||
268 | } | ||
269 | } | ||
270 | } | ||
271 | |||
272 | ret = 1; | ||
273 | |||
274 | err: | ||
275 | if (new_ctx) | ||
276 | BN_CTX_free(new_ctx); | ||
277 | return ret; | ||
278 | } | ||
279 | |||
280 | |||
281 | int ec_GFp_simple_group_get_degree(const EC_GROUP *group) | ||
282 | { | ||
283 | return BN_num_bits(&group->field); | ||
284 | } | ||
285 | |||
286 | |||
287 | int ec_GFp_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx) | ||
288 | { | ||
289 | int ret = 0; | ||
290 | BIGNUM *a,*b,*order,*tmp_1,*tmp_2; | ||
291 | const BIGNUM *p = &group->field; | ||
292 | BN_CTX *new_ctx = NULL; | ||
293 | |||
294 | if (ctx == NULL) | ||
295 | { | ||
296 | ctx = new_ctx = BN_CTX_new(); | ||
297 | if (ctx == NULL) | ||
298 | { | ||
299 | ECerr(EC_F_EC_GFP_SIMPLE_GROUP_CHECK_DISCRIMINANT, ERR_R_MALLOC_FAILURE); | ||
300 | goto err; | ||
301 | } | ||
302 | } | ||
303 | BN_CTX_start(ctx); | ||
304 | a = BN_CTX_get(ctx); | ||
305 | b = BN_CTX_get(ctx); | ||
306 | tmp_1 = BN_CTX_get(ctx); | ||
307 | tmp_2 = BN_CTX_get(ctx); | ||
308 | order = BN_CTX_get(ctx); | ||
309 | if (order == NULL) goto err; | ||
310 | |||
311 | if (group->meth->field_decode) | ||
312 | { | ||
313 | if (!group->meth->field_decode(group, a, &group->a, ctx)) goto err; | ||
314 | if (!group->meth->field_decode(group, b, &group->b, ctx)) goto err; | ||
315 | } | ||
316 | else | ||
317 | { | ||
318 | if (!BN_copy(a, &group->a)) goto err; | ||
319 | if (!BN_copy(b, &group->b)) goto err; | ||
320 | } | ||
321 | |||
322 | /* check the discriminant: | ||
323 | * y^2 = x^3 + a*x + b is an elliptic curve <=> 4*a^3 + 27*b^2 != 0 (mod p) | ||
324 | * 0 =< a, b < p */ | ||
325 | if (BN_is_zero(a)) | ||
326 | { | ||
327 | if (BN_is_zero(b)) goto err; | ||
328 | } | ||
329 | else if (!BN_is_zero(b)) | ||
330 | { | ||
331 | if (!BN_mod_sqr(tmp_1, a, p, ctx)) goto err; | ||
332 | if (!BN_mod_mul(tmp_2, tmp_1, a, p, ctx)) goto err; | ||
333 | if (!BN_lshift(tmp_1, tmp_2, 2)) goto err; | ||
334 | /* tmp_1 = 4*a^3 */ | ||
335 | |||
336 | if (!BN_mod_sqr(tmp_2, b, p, ctx)) goto err; | ||
337 | if (!BN_mul_word(tmp_2, 27)) goto err; | ||
338 | /* tmp_2 = 27*b^2 */ | ||
339 | |||
340 | if (!BN_mod_add(a, tmp_1, tmp_2, p, ctx)) goto err; | ||
341 | if (BN_is_zero(a)) goto err; | ||
342 | } | ||
343 | ret = 1; | ||
344 | |||
345 | err: | ||
346 | if (ctx != NULL) | ||
347 | BN_CTX_end(ctx); | ||
348 | if (new_ctx != NULL) | ||
349 | BN_CTX_free(new_ctx); | ||
350 | return ret; | ||
351 | } | ||
352 | |||
353 | |||
354 | int ec_GFp_simple_point_init(EC_POINT *point) | ||
355 | { | ||
356 | BN_init(&point->X); | ||
357 | BN_init(&point->Y); | ||
358 | BN_init(&point->Z); | ||
359 | point->Z_is_one = 0; | ||
360 | |||
361 | return 1; | ||
362 | } | ||
363 | |||
364 | |||
365 | void ec_GFp_simple_point_finish(EC_POINT *point) | ||
366 | { | ||
367 | BN_free(&point->X); | ||
368 | BN_free(&point->Y); | ||
369 | BN_free(&point->Z); | ||
370 | } | ||
371 | |||
372 | |||
373 | void ec_GFp_simple_point_clear_finish(EC_POINT *point) | ||
374 | { | ||
375 | BN_clear_free(&point->X); | ||
376 | BN_clear_free(&point->Y); | ||
377 | BN_clear_free(&point->Z); | ||
378 | point->Z_is_one = 0; | ||
379 | } | ||
380 | |||
381 | |||
382 | int ec_GFp_simple_point_copy(EC_POINT *dest, const EC_POINT *src) | ||
383 | { | ||
384 | if (!BN_copy(&dest->X, &src->X)) return 0; | ||
385 | if (!BN_copy(&dest->Y, &src->Y)) return 0; | ||
386 | if (!BN_copy(&dest->Z, &src->Z)) return 0; | ||
387 | dest->Z_is_one = src->Z_is_one; | ||
388 | |||
389 | return 1; | ||
390 | } | ||
391 | |||
392 | |||
393 | int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *group, EC_POINT *point) | ||
394 | { | ||
395 | point->Z_is_one = 0; | ||
396 | BN_zero(&point->Z); | ||
397 | return 1; | ||
398 | } | ||
399 | |||
400 | |||
401 | int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *group, EC_POINT *point, | ||
402 | const BIGNUM *x, const BIGNUM *y, const BIGNUM *z, BN_CTX *ctx) | ||
403 | { | ||
404 | BN_CTX *new_ctx = NULL; | ||
405 | int ret = 0; | ||
406 | |||
407 | if (ctx == NULL) | ||
408 | { | ||
409 | ctx = new_ctx = BN_CTX_new(); | ||
410 | if (ctx == NULL) | ||
411 | return 0; | ||
412 | } | ||
413 | |||
414 | if (x != NULL) | ||
415 | { | ||
416 | if (!BN_nnmod(&point->X, x, &group->field, ctx)) goto err; | ||
417 | if (group->meth->field_encode) | ||
418 | { | ||
419 | if (!group->meth->field_encode(group, &point->X, &point->X, ctx)) goto err; | ||
420 | } | ||
421 | } | ||
422 | |||
423 | if (y != NULL) | ||
424 | { | ||
425 | if (!BN_nnmod(&point->Y, y, &group->field, ctx)) goto err; | ||
426 | if (group->meth->field_encode) | ||
427 | { | ||
428 | if (!group->meth->field_encode(group, &point->Y, &point->Y, ctx)) goto err; | ||
429 | } | ||
430 | } | ||
431 | |||
432 | if (z != NULL) | ||
433 | { | ||
434 | int Z_is_one; | ||
435 | |||
436 | if (!BN_nnmod(&point->Z, z, &group->field, ctx)) goto err; | ||
437 | Z_is_one = BN_is_one(&point->Z); | ||
438 | if (group->meth->field_encode) | ||
439 | { | ||
440 | if (Z_is_one && (group->meth->field_set_to_one != 0)) | ||
441 | { | ||
442 | if (!group->meth->field_set_to_one(group, &point->Z, ctx)) goto err; | ||
443 | } | ||
444 | else | ||
445 | { | ||
446 | if (!group->meth->field_encode(group, &point->Z, &point->Z, ctx)) goto err; | ||
447 | } | ||
448 | } | ||
449 | point->Z_is_one = Z_is_one; | ||
450 | } | ||
451 | |||
452 | ret = 1; | ||
453 | |||
454 | err: | ||
455 | if (new_ctx != NULL) | ||
456 | BN_CTX_free(new_ctx); | ||
457 | return ret; | ||
458 | } | ||
459 | |||
460 | |||
461 | int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *group, const EC_POINT *point, | ||
462 | BIGNUM *x, BIGNUM *y, BIGNUM *z, BN_CTX *ctx) | ||
463 | { | ||
464 | BN_CTX *new_ctx = NULL; | ||
465 | int ret = 0; | ||
466 | |||
467 | if (group->meth->field_decode != 0) | ||
468 | { | ||
469 | if (ctx == NULL) | ||
470 | { | ||
471 | ctx = new_ctx = BN_CTX_new(); | ||
472 | if (ctx == NULL) | ||
473 | return 0; | ||
474 | } | ||
475 | |||
476 | if (x != NULL) | ||
477 | { | ||
478 | if (!group->meth->field_decode(group, x, &point->X, ctx)) goto err; | ||
479 | } | ||
480 | if (y != NULL) | ||
481 | { | ||
482 | if (!group->meth->field_decode(group, y, &point->Y, ctx)) goto err; | ||
483 | } | ||
484 | if (z != NULL) | ||
485 | { | ||
486 | if (!group->meth->field_decode(group, z, &point->Z, ctx)) goto err; | ||
487 | } | ||
488 | } | ||
489 | else | ||
490 | { | ||
491 | if (x != NULL) | ||
492 | { | ||
493 | if (!BN_copy(x, &point->X)) goto err; | ||
494 | } | ||
495 | if (y != NULL) | ||
496 | { | ||
497 | if (!BN_copy(y, &point->Y)) goto err; | ||
498 | } | ||
499 | if (z != NULL) | ||
500 | { | ||
501 | if (!BN_copy(z, &point->Z)) goto err; | ||
502 | } | ||
503 | } | ||
504 | |||
505 | ret = 1; | ||
506 | |||
507 | err: | ||
508 | if (new_ctx != NULL) | ||
509 | BN_CTX_free(new_ctx); | ||
510 | return ret; | ||
511 | } | ||
512 | |||
513 | |||
514 | int ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point, | ||
515 | const BIGNUM *x, const BIGNUM *y, BN_CTX *ctx) | ||
516 | { | ||
517 | if (x == NULL || y == NULL) | ||
518 | { | ||
519 | /* unlike for projective coordinates, we do not tolerate this */ | ||
520 | ECerr(EC_F_EC_GFP_SIMPLE_POINT_SET_AFFINE_COORDINATES, ERR_R_PASSED_NULL_PARAMETER); | ||
521 | return 0; | ||
522 | } | ||
523 | |||
524 | return EC_POINT_set_Jprojective_coordinates_GFp(group, point, x, y, BN_value_one(), ctx); | ||
525 | } | ||
526 | |||
527 | |||
528 | int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, const EC_POINT *point, | ||
529 | BIGNUM *x, BIGNUM *y, BN_CTX *ctx) | ||
530 | { | ||
531 | BN_CTX *new_ctx = NULL; | ||
532 | BIGNUM *Z, *Z_1, *Z_2, *Z_3; | ||
533 | const BIGNUM *Z_; | ||
534 | int ret = 0; | ||
535 | |||
536 | if (EC_POINT_is_at_infinity(group, point)) | ||
537 | { | ||
538 | ECerr(EC_F_EC_GFP_SIMPLE_POINT_GET_AFFINE_COORDINATES, EC_R_POINT_AT_INFINITY); | ||
539 | return 0; | ||
540 | } | ||
541 | |||
542 | if (ctx == NULL) | ||
543 | { | ||
544 | ctx = new_ctx = BN_CTX_new(); | ||
545 | if (ctx == NULL) | ||
546 | return 0; | ||
547 | } | ||
548 | |||
549 | BN_CTX_start(ctx); | ||
550 | Z = BN_CTX_get(ctx); | ||
551 | Z_1 = BN_CTX_get(ctx); | ||
552 | Z_2 = BN_CTX_get(ctx); | ||
553 | Z_3 = BN_CTX_get(ctx); | ||
554 | if (Z_3 == NULL) goto err; | ||
555 | |||
556 | /* transform (X, Y, Z) into (x, y) := (X/Z^2, Y/Z^3) */ | ||
557 | |||
558 | if (group->meth->field_decode) | ||
559 | { | ||
560 | if (!group->meth->field_decode(group, Z, &point->Z, ctx)) goto err; | ||
561 | Z_ = Z; | ||
562 | } | ||
563 | else | ||
564 | { | ||
565 | Z_ = &point->Z; | ||
566 | } | ||
567 | |||
568 | if (BN_is_one(Z_)) | ||
569 | { | ||
570 | if (group->meth->field_decode) | ||
571 | { | ||
572 | if (x != NULL) | ||
573 | { | ||
574 | if (!group->meth->field_decode(group, x, &point->X, ctx)) goto err; | ||
575 | } | ||
576 | if (y != NULL) | ||
577 | { | ||
578 | if (!group->meth->field_decode(group, y, &point->Y, ctx)) goto err; | ||
579 | } | ||
580 | } | ||
581 | else | ||
582 | { | ||
583 | if (x != NULL) | ||
584 | { | ||
585 | if (!BN_copy(x, &point->X)) goto err; | ||
586 | } | ||
587 | if (y != NULL) | ||
588 | { | ||
589 | if (!BN_copy(y, &point->Y)) goto err; | ||
590 | } | ||
591 | } | ||
592 | } | ||
593 | else | ||
594 | { | ||
595 | if (!BN_mod_inverse(Z_1, Z_, &group->field, ctx)) | ||
596 | { | ||
597 | ECerr(EC_F_EC_GFP_SIMPLE_POINT_GET_AFFINE_COORDINATES, ERR_R_BN_LIB); | ||
598 | goto err; | ||
599 | } | ||
600 | |||
601 | if (group->meth->field_encode == 0) | ||
602 | { | ||
603 | /* field_sqr works on standard representation */ | ||
604 | if (!group->meth->field_sqr(group, Z_2, Z_1, ctx)) goto err; | ||
605 | } | ||
606 | else | ||
607 | { | ||
608 | if (!BN_mod_sqr(Z_2, Z_1, &group->field, ctx)) goto err; | ||
609 | } | ||
610 | |||
611 | if (x != NULL) | ||
612 | { | ||
613 | /* in the Montgomery case, field_mul will cancel out Montgomery factor in X: */ | ||
614 | if (!group->meth->field_mul(group, x, &point->X, Z_2, ctx)) goto err; | ||
615 | } | ||
616 | |||
617 | if (y != NULL) | ||
618 | { | ||
619 | if (group->meth->field_encode == 0) | ||
620 | { | ||
621 | /* field_mul works on standard representation */ | ||
622 | if (!group->meth->field_mul(group, Z_3, Z_2, Z_1, ctx)) goto err; | ||
623 | } | ||
624 | else | ||
625 | { | ||
626 | if (!BN_mod_mul(Z_3, Z_2, Z_1, &group->field, ctx)) goto err; | ||
627 | } | ||
628 | |||
629 | /* in the Montgomery case, field_mul will cancel out Montgomery factor in Y: */ | ||
630 | if (!group->meth->field_mul(group, y, &point->Y, Z_3, ctx)) goto err; | ||
631 | } | ||
632 | } | ||
633 | |||
634 | ret = 1; | ||
635 | |||
636 | err: | ||
637 | BN_CTX_end(ctx); | ||
638 | if (new_ctx != NULL) | ||
639 | BN_CTX_free(new_ctx); | ||
640 | return ret; | ||
641 | } | ||
642 | |||
643 | int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx) | ||
644 | { | ||
645 | int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *); | ||
646 | int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); | ||
647 | const BIGNUM *p; | ||
648 | BN_CTX *new_ctx = NULL; | ||
649 | BIGNUM *n0, *n1, *n2, *n3, *n4, *n5, *n6; | ||
650 | int ret = 0; | ||
651 | |||
652 | if (a == b) | ||
653 | return EC_POINT_dbl(group, r, a, ctx); | ||
654 | if (EC_POINT_is_at_infinity(group, a)) | ||
655 | return EC_POINT_copy(r, b); | ||
656 | if (EC_POINT_is_at_infinity(group, b)) | ||
657 | return EC_POINT_copy(r, a); | ||
658 | |||
659 | field_mul = group->meth->field_mul; | ||
660 | field_sqr = group->meth->field_sqr; | ||
661 | p = &group->field; | ||
662 | |||
663 | if (ctx == NULL) | ||
664 | { | ||
665 | ctx = new_ctx = BN_CTX_new(); | ||
666 | if (ctx == NULL) | ||
667 | return 0; | ||
668 | } | ||
669 | |||
670 | BN_CTX_start(ctx); | ||
671 | n0 = BN_CTX_get(ctx); | ||
672 | n1 = BN_CTX_get(ctx); | ||
673 | n2 = BN_CTX_get(ctx); | ||
674 | n3 = BN_CTX_get(ctx); | ||
675 | n4 = BN_CTX_get(ctx); | ||
676 | n5 = BN_CTX_get(ctx); | ||
677 | n6 = BN_CTX_get(ctx); | ||
678 | if (n6 == NULL) goto end; | ||
679 | |||
680 | /* Note that in this function we must not read components of 'a' or 'b' | ||
681 | * once we have written the corresponding components of 'r'. | ||
682 | * ('r' might be one of 'a' or 'b'.) | ||
683 | */ | ||
684 | |||
685 | /* n1, n2 */ | ||
686 | if (b->Z_is_one) | ||
687 | { | ||
688 | if (!BN_copy(n1, &a->X)) goto end; | ||
689 | if (!BN_copy(n2, &a->Y)) goto end; | ||
690 | /* n1 = X_a */ | ||
691 | /* n2 = Y_a */ | ||
692 | } | ||
693 | else | ||
694 | { | ||
695 | if (!field_sqr(group, n0, &b->Z, ctx)) goto end; | ||
696 | if (!field_mul(group, n1, &a->X, n0, ctx)) goto end; | ||
697 | /* n1 = X_a * Z_b^2 */ | ||
698 | |||
699 | if (!field_mul(group, n0, n0, &b->Z, ctx)) goto end; | ||
700 | if (!field_mul(group, n2, &a->Y, n0, ctx)) goto end; | ||
701 | /* n2 = Y_a * Z_b^3 */ | ||
702 | } | ||
703 | |||
704 | /* n3, n4 */ | ||
705 | if (a->Z_is_one) | ||
706 | { | ||
707 | if (!BN_copy(n3, &b->X)) goto end; | ||
708 | if (!BN_copy(n4, &b->Y)) goto end; | ||
709 | /* n3 = X_b */ | ||
710 | /* n4 = Y_b */ | ||
711 | } | ||
712 | else | ||
713 | { | ||
714 | if (!field_sqr(group, n0, &a->Z, ctx)) goto end; | ||
715 | if (!field_mul(group, n3, &b->X, n0, ctx)) goto end; | ||
716 | /* n3 = X_b * Z_a^2 */ | ||
717 | |||
718 | if (!field_mul(group, n0, n0, &a->Z, ctx)) goto end; | ||
719 | if (!field_mul(group, n4, &b->Y, n0, ctx)) goto end; | ||
720 | /* n4 = Y_b * Z_a^3 */ | ||
721 | } | ||
722 | |||
723 | /* n5, n6 */ | ||
724 | if (!BN_mod_sub_quick(n5, n1, n3, p)) goto end; | ||
725 | if (!BN_mod_sub_quick(n6, n2, n4, p)) goto end; | ||
726 | /* n5 = n1 - n3 */ | ||
727 | /* n6 = n2 - n4 */ | ||
728 | |||
729 | if (BN_is_zero(n5)) | ||
730 | { | ||
731 | if (BN_is_zero(n6)) | ||
732 | { | ||
733 | /* a is the same point as b */ | ||
734 | BN_CTX_end(ctx); | ||
735 | ret = EC_POINT_dbl(group, r, a, ctx); | ||
736 | ctx = NULL; | ||
737 | goto end; | ||
738 | } | ||
739 | else | ||
740 | { | ||
741 | /* a is the inverse of b */ | ||
742 | BN_zero(&r->Z); | ||
743 | r->Z_is_one = 0; | ||
744 | ret = 1; | ||
745 | goto end; | ||
746 | } | ||
747 | } | ||
748 | |||
749 | /* 'n7', 'n8' */ | ||
750 | if (!BN_mod_add_quick(n1, n1, n3, p)) goto end; | ||
751 | if (!BN_mod_add_quick(n2, n2, n4, p)) goto end; | ||
752 | /* 'n7' = n1 + n3 */ | ||
753 | /* 'n8' = n2 + n4 */ | ||
754 | |||
755 | /* Z_r */ | ||
756 | if (a->Z_is_one && b->Z_is_one) | ||
757 | { | ||
758 | if (!BN_copy(&r->Z, n5)) goto end; | ||
759 | } | ||
760 | else | ||
761 | { | ||
762 | if (a->Z_is_one) | ||
763 | { if (!BN_copy(n0, &b->Z)) goto end; } | ||
764 | else if (b->Z_is_one) | ||
765 | { if (!BN_copy(n0, &a->Z)) goto end; } | ||
766 | else | ||
767 | { if (!field_mul(group, n0, &a->Z, &b->Z, ctx)) goto end; } | ||
768 | if (!field_mul(group, &r->Z, n0, n5, ctx)) goto end; | ||
769 | } | ||
770 | r->Z_is_one = 0; | ||
771 | /* Z_r = Z_a * Z_b * n5 */ | ||
772 | |||
773 | /* X_r */ | ||
774 | if (!field_sqr(group, n0, n6, ctx)) goto end; | ||
775 | if (!field_sqr(group, n4, n5, ctx)) goto end; | ||
776 | if (!field_mul(group, n3, n1, n4, ctx)) goto end; | ||
777 | if (!BN_mod_sub_quick(&r->X, n0, n3, p)) goto end; | ||
778 | /* X_r = n6^2 - n5^2 * 'n7' */ | ||
779 | |||
780 | /* 'n9' */ | ||
781 | if (!BN_mod_lshift1_quick(n0, &r->X, p)) goto end; | ||
782 | if (!BN_mod_sub_quick(n0, n3, n0, p)) goto end; | ||
783 | /* n9 = n5^2 * 'n7' - 2 * X_r */ | ||
784 | |||
785 | /* Y_r */ | ||
786 | if (!field_mul(group, n0, n0, n6, ctx)) goto end; | ||
787 | if (!field_mul(group, n5, n4, n5, ctx)) goto end; /* now n5 is n5^3 */ | ||
788 | if (!field_mul(group, n1, n2, n5, ctx)) goto end; | ||
789 | if (!BN_mod_sub_quick(n0, n0, n1, p)) goto end; | ||
790 | if (BN_is_odd(n0)) | ||
791 | if (!BN_add(n0, n0, p)) goto end; | ||
792 | /* now 0 <= n0 < 2*p, and n0 is even */ | ||
793 | if (!BN_rshift1(&r->Y, n0)) goto end; | ||
794 | /* Y_r = (n6 * 'n9' - 'n8' * 'n5^3') / 2 */ | ||
795 | |||
796 | ret = 1; | ||
797 | |||
798 | end: | ||
799 | if (ctx) /* otherwise we already called BN_CTX_end */ | ||
800 | BN_CTX_end(ctx); | ||
801 | if (new_ctx != NULL) | ||
802 | BN_CTX_free(new_ctx); | ||
803 | return ret; | ||
804 | } | ||
805 | |||
806 | |||
807 | int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, BN_CTX *ctx) | ||
808 | { | ||
809 | int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *); | ||
810 | int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); | ||
811 | const BIGNUM *p; | ||
812 | BN_CTX *new_ctx = NULL; | ||
813 | BIGNUM *n0, *n1, *n2, *n3; | ||
814 | int ret = 0; | ||
815 | |||
816 | if (EC_POINT_is_at_infinity(group, a)) | ||
817 | { | ||
818 | BN_zero(&r->Z); | ||
819 | r->Z_is_one = 0; | ||
820 | return 1; | ||
821 | } | ||
822 | |||
823 | field_mul = group->meth->field_mul; | ||
824 | field_sqr = group->meth->field_sqr; | ||
825 | p = &group->field; | ||
826 | |||
827 | if (ctx == NULL) | ||
828 | { | ||
829 | ctx = new_ctx = BN_CTX_new(); | ||
830 | if (ctx == NULL) | ||
831 | return 0; | ||
832 | } | ||
833 | |||
834 | BN_CTX_start(ctx); | ||
835 | n0 = BN_CTX_get(ctx); | ||
836 | n1 = BN_CTX_get(ctx); | ||
837 | n2 = BN_CTX_get(ctx); | ||
838 | n3 = BN_CTX_get(ctx); | ||
839 | if (n3 == NULL) goto err; | ||
840 | |||
841 | /* Note that in this function we must not read components of 'a' | ||
842 | * once we have written the corresponding components of 'r'. | ||
843 | * ('r' might the same as 'a'.) | ||
844 | */ | ||
845 | |||
846 | /* n1 */ | ||
847 | if (a->Z_is_one) | ||
848 | { | ||
849 | if (!field_sqr(group, n0, &a->X, ctx)) goto err; | ||
850 | if (!BN_mod_lshift1_quick(n1, n0, p)) goto err; | ||
851 | if (!BN_mod_add_quick(n0, n0, n1, p)) goto err; | ||
852 | if (!BN_mod_add_quick(n1, n0, &group->a, p)) goto err; | ||
853 | /* n1 = 3 * X_a^2 + a_curve */ | ||
854 | } | ||
855 | else if (group->a_is_minus3) | ||
856 | { | ||
857 | if (!field_sqr(group, n1, &a->Z, ctx)) goto err; | ||
858 | if (!BN_mod_add_quick(n0, &a->X, n1, p)) goto err; | ||
859 | if (!BN_mod_sub_quick(n2, &a->X, n1, p)) goto err; | ||
860 | if (!field_mul(group, n1, n0, n2, ctx)) goto err; | ||
861 | if (!BN_mod_lshift1_quick(n0, n1, p)) goto err; | ||
862 | if (!BN_mod_add_quick(n1, n0, n1, p)) goto err; | ||
863 | /* n1 = 3 * (X_a + Z_a^2) * (X_a - Z_a^2) | ||
864 | * = 3 * X_a^2 - 3 * Z_a^4 */ | ||
865 | } | ||
866 | else | ||
867 | { | ||
868 | if (!field_sqr(group, n0, &a->X, ctx)) goto err; | ||
869 | if (!BN_mod_lshift1_quick(n1, n0, p)) goto err; | ||
870 | if (!BN_mod_add_quick(n0, n0, n1, p)) goto err; | ||
871 | if (!field_sqr(group, n1, &a->Z, ctx)) goto err; | ||
872 | if (!field_sqr(group, n1, n1, ctx)) goto err; | ||
873 | if (!field_mul(group, n1, n1, &group->a, ctx)) goto err; | ||
874 | if (!BN_mod_add_quick(n1, n1, n0, p)) goto err; | ||
875 | /* n1 = 3 * X_a^2 + a_curve * Z_a^4 */ | ||
876 | } | ||
877 | |||
878 | /* Z_r */ | ||
879 | if (a->Z_is_one) | ||
880 | { | ||
881 | if (!BN_copy(n0, &a->Y)) goto err; | ||
882 | } | ||
883 | else | ||
884 | { | ||
885 | if (!field_mul(group, n0, &a->Y, &a->Z, ctx)) goto err; | ||
886 | } | ||
887 | if (!BN_mod_lshift1_quick(&r->Z, n0, p)) goto err; | ||
888 | r->Z_is_one = 0; | ||
889 | /* Z_r = 2 * Y_a * Z_a */ | ||
890 | |||
891 | /* n2 */ | ||
892 | if (!field_sqr(group, n3, &a->Y, ctx)) goto err; | ||
893 | if (!field_mul(group, n2, &a->X, n3, ctx)) goto err; | ||
894 | if (!BN_mod_lshift_quick(n2, n2, 2, p)) goto err; | ||
895 | /* n2 = 4 * X_a * Y_a^2 */ | ||
896 | |||
897 | /* X_r */ | ||
898 | if (!BN_mod_lshift1_quick(n0, n2, p)) goto err; | ||
899 | if (!field_sqr(group, &r->X, n1, ctx)) goto err; | ||
900 | if (!BN_mod_sub_quick(&r->X, &r->X, n0, p)) goto err; | ||
901 | /* X_r = n1^2 - 2 * n2 */ | ||
902 | |||
903 | /* n3 */ | ||
904 | if (!field_sqr(group, n0, n3, ctx)) goto err; | ||
905 | if (!BN_mod_lshift_quick(n3, n0, 3, p)) goto err; | ||
906 | /* n3 = 8 * Y_a^4 */ | ||
907 | |||
908 | /* Y_r */ | ||
909 | if (!BN_mod_sub_quick(n0, n2, &r->X, p)) goto err; | ||
910 | if (!field_mul(group, n0, n1, n0, ctx)) goto err; | ||
911 | if (!BN_mod_sub_quick(&r->Y, n0, n3, p)) goto err; | ||
912 | /* Y_r = n1 * (n2 - X_r) - n3 */ | ||
913 | |||
914 | ret = 1; | ||
915 | |||
916 | err: | ||
917 | BN_CTX_end(ctx); | ||
918 | if (new_ctx != NULL) | ||
919 | BN_CTX_free(new_ctx); | ||
920 | return ret; | ||
921 | } | ||
922 | |||
923 | |||
924 | int ec_GFp_simple_invert(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx) | ||
925 | { | ||
926 | if (EC_POINT_is_at_infinity(group, point) || BN_is_zero(&point->Y)) | ||
927 | /* point is its own inverse */ | ||
928 | return 1; | ||
929 | |||
930 | return BN_usub(&point->Y, &group->field, &point->Y); | ||
931 | } | ||
932 | |||
933 | |||
934 | int ec_GFp_simple_is_at_infinity(const EC_GROUP *group, const EC_POINT *point) | ||
935 | { | ||
936 | return BN_is_zero(&point->Z); | ||
937 | } | ||
938 | |||
939 | |||
940 | int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx) | ||
941 | { | ||
942 | int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *); | ||
943 | int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); | ||
944 | const BIGNUM *p; | ||
945 | BN_CTX *new_ctx = NULL; | ||
946 | BIGNUM *rh, *tmp, *Z4, *Z6; | ||
947 | int ret = -1; | ||
948 | |||
949 | if (EC_POINT_is_at_infinity(group, point)) | ||
950 | return 1; | ||
951 | |||
952 | field_mul = group->meth->field_mul; | ||
953 | field_sqr = group->meth->field_sqr; | ||
954 | p = &group->field; | ||
955 | |||
956 | if (ctx == NULL) | ||
957 | { | ||
958 | ctx = new_ctx = BN_CTX_new(); | ||
959 | if (ctx == NULL) | ||
960 | return -1; | ||
961 | } | ||
962 | |||
963 | BN_CTX_start(ctx); | ||
964 | rh = BN_CTX_get(ctx); | ||
965 | tmp = BN_CTX_get(ctx); | ||
966 | Z4 = BN_CTX_get(ctx); | ||
967 | Z6 = BN_CTX_get(ctx); | ||
968 | if (Z6 == NULL) goto err; | ||
969 | |||
970 | /* We have a curve defined by a Weierstrass equation | ||
971 | * y^2 = x^3 + a*x + b. | ||
972 | * The point to consider is given in Jacobian projective coordinates | ||
973 | * where (X, Y, Z) represents (x, y) = (X/Z^2, Y/Z^3). | ||
974 | * Substituting this and multiplying by Z^6 transforms the above equation into | ||
975 | * Y^2 = X^3 + a*X*Z^4 + b*Z^6. | ||
976 | * To test this, we add up the right-hand side in 'rh'. | ||
977 | */ | ||
978 | |||
979 | /* rh := X^2 */ | ||
980 | if (!field_sqr(group, rh, &point->X, ctx)) goto err; | ||
981 | |||
982 | if (!point->Z_is_one) | ||
983 | { | ||
984 | if (!field_sqr(group, tmp, &point->Z, ctx)) goto err; | ||
985 | if (!field_sqr(group, Z4, tmp, ctx)) goto err; | ||
986 | if (!field_mul(group, Z6, Z4, tmp, ctx)) goto err; | ||
987 | |||
988 | /* rh := (rh + a*Z^4)*X */ | ||
989 | if (group->a_is_minus3) | ||
990 | { | ||
991 | if (!BN_mod_lshift1_quick(tmp, Z4, p)) goto err; | ||
992 | if (!BN_mod_add_quick(tmp, tmp, Z4, p)) goto err; | ||
993 | if (!BN_mod_sub_quick(rh, rh, tmp, p)) goto err; | ||
994 | if (!field_mul(group, rh, rh, &point->X, ctx)) goto err; | ||
995 | } | ||
996 | else | ||
997 | { | ||
998 | if (!field_mul(group, tmp, Z4, &group->a, ctx)) goto err; | ||
999 | if (!BN_mod_add_quick(rh, rh, tmp, p)) goto err; | ||
1000 | if (!field_mul(group, rh, rh, &point->X, ctx)) goto err; | ||
1001 | } | ||
1002 | |||
1003 | /* rh := rh + b*Z^6 */ | ||
1004 | if (!field_mul(group, tmp, &group->b, Z6, ctx)) goto err; | ||
1005 | if (!BN_mod_add_quick(rh, rh, tmp, p)) goto err; | ||
1006 | } | ||
1007 | else | ||
1008 | { | ||
1009 | /* point->Z_is_one */ | ||
1010 | |||
1011 | /* rh := (rh + a)*X */ | ||
1012 | if (!BN_mod_add_quick(rh, rh, &group->a, p)) goto err; | ||
1013 | if (!field_mul(group, rh, rh, &point->X, ctx)) goto err; | ||
1014 | /* rh := rh + b */ | ||
1015 | if (!BN_mod_add_quick(rh, rh, &group->b, p)) goto err; | ||
1016 | } | ||
1017 | |||
1018 | /* 'lh' := Y^2 */ | ||
1019 | if (!field_sqr(group, tmp, &point->Y, ctx)) goto err; | ||
1020 | |||
1021 | ret = (0 == BN_ucmp(tmp, rh)); | ||
1022 | |||
1023 | err: | ||
1024 | BN_CTX_end(ctx); | ||
1025 | if (new_ctx != NULL) | ||
1026 | BN_CTX_free(new_ctx); | ||
1027 | return ret; | ||
1028 | } | ||
1029 | |||
1030 | |||
1031 | int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx) | ||
1032 | { | ||
1033 | /* return values: | ||
1034 | * -1 error | ||
1035 | * 0 equal (in affine coordinates) | ||
1036 | * 1 not equal | ||
1037 | */ | ||
1038 | |||
1039 | int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *); | ||
1040 | int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); | ||
1041 | BN_CTX *new_ctx = NULL; | ||
1042 | BIGNUM *tmp1, *tmp2, *Za23, *Zb23; | ||
1043 | const BIGNUM *tmp1_, *tmp2_; | ||
1044 | int ret = -1; | ||
1045 | |||
1046 | if (EC_POINT_is_at_infinity(group, a)) | ||
1047 | { | ||
1048 | return EC_POINT_is_at_infinity(group, b) ? 0 : 1; | ||
1049 | } | ||
1050 | |||
1051 | if (EC_POINT_is_at_infinity(group, b)) | ||
1052 | return 1; | ||
1053 | |||
1054 | if (a->Z_is_one && b->Z_is_one) | ||
1055 | { | ||
1056 | return ((BN_cmp(&a->X, &b->X) == 0) && BN_cmp(&a->Y, &b->Y) == 0) ? 0 : 1; | ||
1057 | } | ||
1058 | |||
1059 | field_mul = group->meth->field_mul; | ||
1060 | field_sqr = group->meth->field_sqr; | ||
1061 | |||
1062 | if (ctx == NULL) | ||
1063 | { | ||
1064 | ctx = new_ctx = BN_CTX_new(); | ||
1065 | if (ctx == NULL) | ||
1066 | return -1; | ||
1067 | } | ||
1068 | |||
1069 | BN_CTX_start(ctx); | ||
1070 | tmp1 = BN_CTX_get(ctx); | ||
1071 | tmp2 = BN_CTX_get(ctx); | ||
1072 | Za23 = BN_CTX_get(ctx); | ||
1073 | Zb23 = BN_CTX_get(ctx); | ||
1074 | if (Zb23 == NULL) goto end; | ||
1075 | |||
1076 | /* We have to decide whether | ||
1077 | * (X_a/Z_a^2, Y_a/Z_a^3) = (X_b/Z_b^2, Y_b/Z_b^3), | ||
1078 | * or equivalently, whether | ||
1079 | * (X_a*Z_b^2, Y_a*Z_b^3) = (X_b*Z_a^2, Y_b*Z_a^3). | ||
1080 | */ | ||
1081 | |||
1082 | if (!b->Z_is_one) | ||
1083 | { | ||
1084 | if (!field_sqr(group, Zb23, &b->Z, ctx)) goto end; | ||
1085 | if (!field_mul(group, tmp1, &a->X, Zb23, ctx)) goto end; | ||
1086 | tmp1_ = tmp1; | ||
1087 | } | ||
1088 | else | ||
1089 | tmp1_ = &a->X; | ||
1090 | if (!a->Z_is_one) | ||
1091 | { | ||
1092 | if (!field_sqr(group, Za23, &a->Z, ctx)) goto end; | ||
1093 | if (!field_mul(group, tmp2, &b->X, Za23, ctx)) goto end; | ||
1094 | tmp2_ = tmp2; | ||
1095 | } | ||
1096 | else | ||
1097 | tmp2_ = &b->X; | ||
1098 | |||
1099 | /* compare X_a*Z_b^2 with X_b*Z_a^2 */ | ||
1100 | if (BN_cmp(tmp1_, tmp2_) != 0) | ||
1101 | { | ||
1102 | ret = 1; /* points differ */ | ||
1103 | goto end; | ||
1104 | } | ||
1105 | |||
1106 | |||
1107 | if (!b->Z_is_one) | ||
1108 | { | ||
1109 | if (!field_mul(group, Zb23, Zb23, &b->Z, ctx)) goto end; | ||
1110 | if (!field_mul(group, tmp1, &a->Y, Zb23, ctx)) goto end; | ||
1111 | /* tmp1_ = tmp1 */ | ||
1112 | } | ||
1113 | else | ||
1114 | tmp1_ = &a->Y; | ||
1115 | if (!a->Z_is_one) | ||
1116 | { | ||
1117 | if (!field_mul(group, Za23, Za23, &a->Z, ctx)) goto end; | ||
1118 | if (!field_mul(group, tmp2, &b->Y, Za23, ctx)) goto end; | ||
1119 | /* tmp2_ = tmp2 */ | ||
1120 | } | ||
1121 | else | ||
1122 | tmp2_ = &b->Y; | ||
1123 | |||
1124 | /* compare Y_a*Z_b^3 with Y_b*Z_a^3 */ | ||
1125 | if (BN_cmp(tmp1_, tmp2_) != 0) | ||
1126 | { | ||
1127 | ret = 1; /* points differ */ | ||
1128 | goto end; | ||
1129 | } | ||
1130 | |||
1131 | /* points are equal */ | ||
1132 | ret = 0; | ||
1133 | |||
1134 | end: | ||
1135 | BN_CTX_end(ctx); | ||
1136 | if (new_ctx != NULL) | ||
1137 | BN_CTX_free(new_ctx); | ||
1138 | return ret; | ||
1139 | } | ||
1140 | |||
1141 | |||
1142 | int ec_GFp_simple_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx) | ||
1143 | { | ||
1144 | BN_CTX *new_ctx = NULL; | ||
1145 | BIGNUM *x, *y; | ||
1146 | int ret = 0; | ||
1147 | |||
1148 | if (point->Z_is_one || EC_POINT_is_at_infinity(group, point)) | ||
1149 | return 1; | ||
1150 | |||
1151 | if (ctx == NULL) | ||
1152 | { | ||
1153 | ctx = new_ctx = BN_CTX_new(); | ||
1154 | if (ctx == NULL) | ||
1155 | return 0; | ||
1156 | } | ||
1157 | |||
1158 | BN_CTX_start(ctx); | ||
1159 | x = BN_CTX_get(ctx); | ||
1160 | y = BN_CTX_get(ctx); | ||
1161 | if (y == NULL) goto err; | ||
1162 | |||
1163 | if (!EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx)) goto err; | ||
1164 | if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) goto err; | ||
1165 | if (!point->Z_is_one) | ||
1166 | { | ||
1167 | ECerr(EC_F_EC_GFP_SIMPLE_MAKE_AFFINE, ERR_R_INTERNAL_ERROR); | ||
1168 | goto err; | ||
1169 | } | ||
1170 | |||
1171 | ret = 1; | ||
1172 | |||
1173 | err: | ||
1174 | BN_CTX_end(ctx); | ||
1175 | if (new_ctx != NULL) | ||
1176 | BN_CTX_free(new_ctx); | ||
1177 | return ret; | ||
1178 | } | ||
1179 | |||
1180 | |||
1181 | int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, EC_POINT *points[], BN_CTX *ctx) | ||
1182 | { | ||
1183 | BN_CTX *new_ctx = NULL; | ||
1184 | BIGNUM *tmp0, *tmp1; | ||
1185 | size_t pow2 = 0; | ||
1186 | BIGNUM **heap = NULL; | ||
1187 | size_t i; | ||
1188 | int ret = 0; | ||
1189 | |||
1190 | if (num == 0) | ||
1191 | return 1; | ||
1192 | |||
1193 | if (ctx == NULL) | ||
1194 | { | ||
1195 | ctx = new_ctx = BN_CTX_new(); | ||
1196 | if (ctx == NULL) | ||
1197 | return 0; | ||
1198 | } | ||
1199 | |||
1200 | BN_CTX_start(ctx); | ||
1201 | tmp0 = BN_CTX_get(ctx); | ||
1202 | tmp1 = BN_CTX_get(ctx); | ||
1203 | if (tmp0 == NULL || tmp1 == NULL) goto err; | ||
1204 | |||
1205 | /* Before converting the individual points, compute inverses of all Z values. | ||
1206 | * Modular inversion is rather slow, but luckily we can do with a single | ||
1207 | * explicit inversion, plus about 3 multiplications per input value. | ||
1208 | */ | ||
1209 | |||
1210 | pow2 = 1; | ||
1211 | while (num > pow2) | ||
1212 | pow2 <<= 1; | ||
1213 | /* Now pow2 is the smallest power of 2 satifsying pow2 >= num. | ||
1214 | * We need twice that. */ | ||
1215 | pow2 <<= 1; | ||
1216 | |||
1217 | heap = OPENSSL_malloc(pow2 * sizeof heap[0]); | ||
1218 | if (heap == NULL) goto err; | ||
1219 | |||
1220 | /* The array is used as a binary tree, exactly as in heapsort: | ||
1221 | * | ||
1222 | * heap[1] | ||
1223 | * heap[2] heap[3] | ||
1224 | * heap[4] heap[5] heap[6] heap[7] | ||
1225 | * heap[8]heap[9] heap[10]heap[11] heap[12]heap[13] heap[14] heap[15] | ||
1226 | * | ||
1227 | * We put the Z's in the last line; | ||
1228 | * then we set each other node to the product of its two child-nodes (where | ||
1229 | * empty or 0 entries are treated as ones); | ||
1230 | * then we invert heap[1]; | ||
1231 | * then we invert each other node by replacing it by the product of its | ||
1232 | * parent (after inversion) and its sibling (before inversion). | ||
1233 | */ | ||
1234 | heap[0] = NULL; | ||
1235 | for (i = pow2/2 - 1; i > 0; i--) | ||
1236 | heap[i] = NULL; | ||
1237 | for (i = 0; i < num; i++) | ||
1238 | heap[pow2/2 + i] = &points[i]->Z; | ||
1239 | for (i = pow2/2 + num; i < pow2; i++) | ||
1240 | heap[i] = NULL; | ||
1241 | |||
1242 | /* set each node to the product of its children */ | ||
1243 | for (i = pow2/2 - 1; i > 0; i--) | ||
1244 | { | ||
1245 | heap[i] = BN_new(); | ||
1246 | if (heap[i] == NULL) goto err; | ||
1247 | |||
1248 | if (heap[2*i] != NULL) | ||
1249 | { | ||
1250 | if ((heap[2*i + 1] == NULL) || BN_is_zero(heap[2*i + 1])) | ||
1251 | { | ||
1252 | if (!BN_copy(heap[i], heap[2*i])) goto err; | ||
1253 | } | ||
1254 | else | ||
1255 | { | ||
1256 | if (BN_is_zero(heap[2*i])) | ||
1257 | { | ||
1258 | if (!BN_copy(heap[i], heap[2*i + 1])) goto err; | ||
1259 | } | ||
1260 | else | ||
1261 | { | ||
1262 | if (!group->meth->field_mul(group, heap[i], | ||
1263 | heap[2*i], heap[2*i + 1], ctx)) goto err; | ||
1264 | } | ||
1265 | } | ||
1266 | } | ||
1267 | } | ||
1268 | |||
1269 | /* invert heap[1] */ | ||
1270 | if (!BN_is_zero(heap[1])) | ||
1271 | { | ||
1272 | if (!BN_mod_inverse(heap[1], heap[1], &group->field, ctx)) | ||
1273 | { | ||
1274 | ECerr(EC_F_EC_GFP_SIMPLE_POINTS_MAKE_AFFINE, ERR_R_BN_LIB); | ||
1275 | goto err; | ||
1276 | } | ||
1277 | } | ||
1278 | if (group->meth->field_encode != 0) | ||
1279 | { | ||
1280 | /* in the Montgomery case, we just turned R*H (representing H) | ||
1281 | * into 1/(R*H), but we need R*(1/H) (representing 1/H); | ||
1282 | * i.e. we have need to multiply by the Montgomery factor twice */ | ||
1283 | if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) goto err; | ||
1284 | if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) goto err; | ||
1285 | } | ||
1286 | |||
1287 | /* set other heap[i]'s to their inverses */ | ||
1288 | for (i = 2; i < pow2/2 + num; i += 2) | ||
1289 | { | ||
1290 | /* i is even */ | ||
1291 | if ((heap[i + 1] != NULL) && !BN_is_zero(heap[i + 1])) | ||
1292 | { | ||
1293 | if (!group->meth->field_mul(group, tmp0, heap[i/2], heap[i + 1], ctx)) goto err; | ||
1294 | if (!group->meth->field_mul(group, tmp1, heap[i/2], heap[i], ctx)) goto err; | ||
1295 | if (!BN_copy(heap[i], tmp0)) goto err; | ||
1296 | if (!BN_copy(heap[i + 1], tmp1)) goto err; | ||
1297 | } | ||
1298 | else | ||
1299 | { | ||
1300 | if (!BN_copy(heap[i], heap[i/2])) goto err; | ||
1301 | } | ||
1302 | } | ||
1303 | |||
1304 | /* we have replaced all non-zero Z's by their inverses, now fix up all the points */ | ||
1305 | for (i = 0; i < num; i++) | ||
1306 | { | ||
1307 | EC_POINT *p = points[i]; | ||
1308 | |||
1309 | if (!BN_is_zero(&p->Z)) | ||
1310 | { | ||
1311 | /* turn (X, Y, 1/Z) into (X/Z^2, Y/Z^3, 1) */ | ||
1312 | |||
1313 | if (!group->meth->field_sqr(group, tmp1, &p->Z, ctx)) goto err; | ||
1314 | if (!group->meth->field_mul(group, &p->X, &p->X, tmp1, ctx)) goto err; | ||
1315 | |||
1316 | if (!group->meth->field_mul(group, tmp1, tmp1, &p->Z, ctx)) goto err; | ||
1317 | if (!group->meth->field_mul(group, &p->Y, &p->Y, tmp1, ctx)) goto err; | ||
1318 | |||
1319 | if (group->meth->field_set_to_one != 0) | ||
1320 | { | ||
1321 | if (!group->meth->field_set_to_one(group, &p->Z, ctx)) goto err; | ||
1322 | } | ||
1323 | else | ||
1324 | { | ||
1325 | if (!BN_one(&p->Z)) goto err; | ||
1326 | } | ||
1327 | p->Z_is_one = 1; | ||
1328 | } | ||
1329 | } | ||
1330 | |||
1331 | ret = 1; | ||
1332 | |||
1333 | err: | ||
1334 | BN_CTX_end(ctx); | ||
1335 | if (new_ctx != NULL) | ||
1336 | BN_CTX_free(new_ctx); | ||
1337 | if (heap != NULL) | ||
1338 | { | ||
1339 | /* heap[pow2/2] .. heap[pow2-1] have not been allocated locally! */ | ||
1340 | for (i = pow2/2 - 1; i > 0; i--) | ||
1341 | { | ||
1342 | if (heap[i] != NULL) | ||
1343 | BN_clear_free(heap[i]); | ||
1344 | } | ||
1345 | OPENSSL_free(heap); | ||
1346 | } | ||
1347 | return ret; | ||
1348 | } | ||
1349 | |||
1350 | |||
1351 | int ec_GFp_simple_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) | ||
1352 | { | ||
1353 | return BN_mod_mul(r, a, b, &group->field, ctx); | ||
1354 | } | ||
1355 | |||
1356 | |||
1357 | int ec_GFp_simple_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, BN_CTX *ctx) | ||
1358 | { | ||
1359 | return BN_mod_sqr(r, a, &group->field, ctx); | ||
1360 | } | ||