xref: /openssl/crypto/ec/ec_lib.c (revision 95a6fbdf) 
1 /*
2  * Copyright 2001-2022 The OpenSSL Project Authors. All Rights Reserved.
3  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4  *
5  * Licensed under the Apache License 2.0 (the "License").  You may not use
6  * this file except in compliance with the License.  You can obtain a copy
7  * in the file LICENSE in the source distribution or at
8  * https://www.openssl.org/source/license.html
9  */
10 
11 /*
12  * EC_GROUP low level APIs are deprecated for public use, but still ok for
13  * internal use.
14  */
15 #include "internal/deprecated.h"
16 
17 #include <string.h>
18 #include <openssl/params.h>
19 #include <openssl/core_names.h>
20 #include <openssl/err.h>
21 #include <openssl/opensslv.h>
22 #include "crypto/ec.h"
23 #include "internal/nelem.h"
24 #include "ec_local.h"
25 
26 /* functions for EC_GROUP objects */
27 
ossl_ec_group_new_ex(OSSL_LIB_CTX * libctx,const char * propq,const EC_METHOD * meth)28 EC_GROUP *ossl_ec_group_new_ex(OSSL_LIB_CTX *libctx, const char *propq,
29                                const EC_METHOD *meth)
30 {
31     EC_GROUP *ret;
32 
33     if (meth == NULL) {
34         ERR_raise(ERR_LIB_EC, EC_R_SLOT_FULL);
35         return NULL;
36     }
37     if (meth->group_init == 0) {
38         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
39         return NULL;
40     }
41 
42     ret = OPENSSL_zalloc(sizeof(*ret));
43     if (ret == NULL) {
44         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
45         return NULL;
46     }
47 
48     ret->libctx = libctx;
49     if (propq != NULL) {
50         ret->propq = OPENSSL_strdup(propq);
51         if (ret->propq == NULL) {
52             ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
53             goto err;
54         }
55     }
56     ret->meth = meth;
57     if ((ret->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
58         ret->order = BN_new();
59         if (ret->order == NULL)
60             goto err;
61         ret->cofactor = BN_new();
62         if (ret->cofactor == NULL)
63             goto err;
64     }
65     ret->asn1_flag = OPENSSL_EC_EXPLICIT_CURVE;
66     ret->asn1_form = POINT_CONVERSION_UNCOMPRESSED;
67     if (!meth->group_init(ret))
68         goto err;
69     return ret;
70 
71  err:
72     BN_free(ret->order);
73     BN_free(ret->cofactor);
74     OPENSSL_free(ret->propq);
75     OPENSSL_free(ret);
76     return NULL;
77 }
78 
79 #ifndef OPENSSL_NO_DEPRECATED_3_0
80 # ifndef FIPS_MODULE
EC_GROUP_new(const EC_METHOD * meth)81 EC_GROUP *EC_GROUP_new(const EC_METHOD *meth)
82 {
83     return ossl_ec_group_new_ex(NULL, NULL, meth);
84 }
85 # endif
86 #endif
87 
EC_pre_comp_free(EC_GROUP * group)88 void EC_pre_comp_free(EC_GROUP *group)
89 {
90     switch (group->pre_comp_type) {
91     case PCT_none:
92         break;
93     case PCT_nistz256:
94 #ifdef ECP_NISTZ256_ASM
95         EC_nistz256_pre_comp_free(group->pre_comp.nistz256);
96 #endif
97         break;
98 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
99     case PCT_nistp224:
100         EC_nistp224_pre_comp_free(group->pre_comp.nistp224);
101         break;
102     case PCT_nistp256:
103         EC_nistp256_pre_comp_free(group->pre_comp.nistp256);
104         break;
105     case PCT_nistp521:
106         EC_nistp521_pre_comp_free(group->pre_comp.nistp521);
107         break;
108 #else
109     case PCT_nistp224:
110     case PCT_nistp256:
111     case PCT_nistp521:
112         break;
113 #endif
114     case PCT_ec:
115         EC_ec_pre_comp_free(group->pre_comp.ec);
116         break;
117     }
118     group->pre_comp.ec = NULL;
119 }
120 
EC_GROUP_free(EC_GROUP * group)121 void EC_GROUP_free(EC_GROUP *group)
122 {
123     if (!group)
124         return;
125 
126     if (group->meth->group_finish != 0)
127         group->meth->group_finish(group);
128 
129     EC_pre_comp_free(group);
130     BN_MONT_CTX_free(group->mont_data);
131     EC_POINT_free(group->generator);
132     BN_free(group->order);
133     BN_free(group->cofactor);
134     OPENSSL_free(group->seed);
135     OPENSSL_free(group->propq);
136     OPENSSL_free(group);
137 }
138 
139 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_GROUP_clear_free(EC_GROUP * group)140 void EC_GROUP_clear_free(EC_GROUP *group)
141 {
142     if (!group)
143         return;
144 
145     if (group->meth->group_clear_finish != 0)
146         group->meth->group_clear_finish(group);
147     else if (group->meth->group_finish != 0)
148         group->meth->group_finish(group);
149 
150     EC_pre_comp_free(group);
151     BN_MONT_CTX_free(group->mont_data);
152     EC_POINT_clear_free(group->generator);
153     BN_clear_free(group->order);
154     BN_clear_free(group->cofactor);
155     OPENSSL_clear_free(group->seed, group->seed_len);
156     OPENSSL_clear_free(group, sizeof(*group));
157 }
158 #endif
159 
EC_GROUP_copy(EC_GROUP * dest,const EC_GROUP * src)160 int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
161 {
162     if (dest->meth->group_copy == 0) {
163         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
164         return 0;
165     }
166     if (dest->meth != src->meth) {
167         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
168         return 0;
169     }
170     if (dest == src)
171         return 1;
172 
173     dest->libctx = src->libctx;
174     dest->curve_name = src->curve_name;
175 
176     /* Copy precomputed */
177     dest->pre_comp_type = src->pre_comp_type;
178     switch (src->pre_comp_type) {
179     case PCT_none:
180         dest->pre_comp.ec = NULL;
181         break;
182     case PCT_nistz256:
183 #ifdef ECP_NISTZ256_ASM
184         dest->pre_comp.nistz256 = EC_nistz256_pre_comp_dup(src->pre_comp.nistz256);
185 #endif
186         break;
187 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
188     case PCT_nistp224:
189         dest->pre_comp.nistp224 = EC_nistp224_pre_comp_dup(src->pre_comp.nistp224);
190         break;
191     case PCT_nistp256:
192         dest->pre_comp.nistp256 = EC_nistp256_pre_comp_dup(src->pre_comp.nistp256);
193         break;
194     case PCT_nistp521:
195         dest->pre_comp.nistp521 = EC_nistp521_pre_comp_dup(src->pre_comp.nistp521);
196         break;
197 #else
198     case PCT_nistp224:
199     case PCT_nistp256:
200     case PCT_nistp521:
201         break;
202 #endif
203     case PCT_ec:
204         dest->pre_comp.ec = EC_ec_pre_comp_dup(src->pre_comp.ec);
205         break;
206     }
207 
208     if (src->mont_data != NULL) {
209         if (dest->mont_data == NULL) {
210             dest->mont_data = BN_MONT_CTX_new();
211             if (dest->mont_data == NULL)
212                 return 0;
213         }
214         if (!BN_MONT_CTX_copy(dest->mont_data, src->mont_data))
215             return 0;
216     } else {
217         /* src->generator == NULL */
218         BN_MONT_CTX_free(dest->mont_data);
219         dest->mont_data = NULL;
220     }
221 
222     if (src->generator != NULL) {
223         if (dest->generator == NULL) {
224             dest->generator = EC_POINT_new(dest);
225             if (dest->generator == NULL)
226                 return 0;
227         }
228         if (!EC_POINT_copy(dest->generator, src->generator))
229             return 0;
230     } else {
231         /* src->generator == NULL */
232         EC_POINT_clear_free(dest->generator);
233         dest->generator = NULL;
234     }
235 
236     if ((src->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
237         if (!BN_copy(dest->order, src->order))
238             return 0;
239         if (!BN_copy(dest->cofactor, src->cofactor))
240             return 0;
241     }
242 
243     dest->asn1_flag = src->asn1_flag;
244     dest->asn1_form = src->asn1_form;
245     dest->decoded_from_explicit_params = src->decoded_from_explicit_params;
246 
247     if (src->seed) {
248         OPENSSL_free(dest->seed);
249         if ((dest->seed = OPENSSL_malloc(src->seed_len)) == NULL) {
250             ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
251             return 0;
252         }
253         if (!memcpy(dest->seed, src->seed, src->seed_len))
254             return 0;
255         dest->seed_len = src->seed_len;
256     } else {
257         OPENSSL_free(dest->seed);
258         dest->seed = NULL;
259         dest->seed_len = 0;
260     }
261 
262     return dest->meth->group_copy(dest, src);
263 }
264 
EC_GROUP_dup(const EC_GROUP * a)265 EC_GROUP *EC_GROUP_dup(const EC_GROUP *a)
266 {
267     EC_GROUP *t = NULL;
268     int ok = 0;
269 
270     if (a == NULL)
271         return NULL;
272 
273     if ((t = ossl_ec_group_new_ex(a->libctx, a->propq, a->meth)) == NULL)
274         return NULL;
275     if (!EC_GROUP_copy(t, a))
276         goto err;
277 
278     ok = 1;
279 
280  err:
281     if (!ok) {
282         EC_GROUP_free(t);
283         return NULL;
284     }
285         return t;
286 }
287 
288 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_GROUP_method_of(const EC_GROUP * group)289 const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group)
290 {
291     return group->meth;
292 }
293 
EC_METHOD_get_field_type(const EC_METHOD * meth)294 int EC_METHOD_get_field_type(const EC_METHOD *meth)
295 {
296     return meth->field_type;
297 }
298 #endif
299 
300 static int ec_precompute_mont_data(EC_GROUP *);
301 
302 /*-
303  * Try computing cofactor from the generator order (n) and field cardinality (q).
304  * This works for all curves of cryptographic interest.
305  *
306  * Hasse thm: q + 1 - 2*sqrt(q) <= n*h <= q + 1 + 2*sqrt(q)
307  * h_min = (q + 1 - 2*sqrt(q))/n
308  * h_max = (q + 1 + 2*sqrt(q))/n
309  * h_max - h_min = 4*sqrt(q)/n
310  * So if n > 4*sqrt(q) holds, there is only one possible value for h:
311  * h = \lfloor (h_min + h_max)/2 \rceil = \lfloor (q + 1)/n \rceil
312  *
313  * Otherwise, zero cofactor and return success.
314  */
ec_guess_cofactor(EC_GROUP * group)315 static int ec_guess_cofactor(EC_GROUP *group) {
316     int ret = 0;
317     BN_CTX *ctx = NULL;
318     BIGNUM *q = NULL;
319 
320     /*-
321      * If the cofactor is too large, we cannot guess it.
322      * The RHS of below is a strict overestimate of lg(4 * sqrt(q))
323      */
324     if (BN_num_bits(group->order) <= (BN_num_bits(group->field) + 1) / 2 + 3) {
325         /* default to 0 */
326         BN_zero(group->cofactor);
327         /* return success */
328         return 1;
329     }
330 
331     if ((ctx = BN_CTX_new_ex(group->libctx)) == NULL)
332         return 0;
333 
334     BN_CTX_start(ctx);
335     if ((q = BN_CTX_get(ctx)) == NULL)
336         goto err;
337 
338     /* set q = 2**m for binary fields; q = p otherwise */
339     if (group->meth->field_type == NID_X9_62_characteristic_two_field) {
340         BN_zero(q);
341         if (!BN_set_bit(q, BN_num_bits(group->field) - 1))
342             goto err;
343     } else {
344         if (!BN_copy(q, group->field))
345             goto err;
346     }
347 
348     /* compute h = \lfloor (q + 1)/n \rceil = \lfloor (q + 1 + n/2)/n \rfloor */
349     if (!BN_rshift1(group->cofactor, group->order) /* n/2 */
350         || !BN_add(group->cofactor, group->cofactor, q) /* q + n/2 */
351         /* q + 1 + n/2 */
352         || !BN_add(group->cofactor, group->cofactor, BN_value_one())
353         /* (q + 1 + n/2)/n */
354         || !BN_div(group->cofactor, NULL, group->cofactor, group->order, ctx))
355         goto err;
356     ret = 1;
357  err:
358     BN_CTX_end(ctx);
359     BN_CTX_free(ctx);
360     return ret;
361 }
362 
EC_GROUP_set_generator(EC_GROUP * group,const EC_POINT * generator,const BIGNUM * order,const BIGNUM * cofactor)363 int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
364                            const BIGNUM *order, const BIGNUM *cofactor)
365 {
366     if (generator == NULL) {
367         ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
368         return 0;
369     }
370 
371     /* require group->field >= 1 */
372     if (group->field == NULL || BN_is_zero(group->field)
373         || BN_is_negative(group->field)) {
374         ERR_raise(ERR_LIB_EC, EC_R_INVALID_FIELD);
375         return 0;
376     }
377 
378     /*-
379      * - require order >= 1
380      * - enforce upper bound due to Hasse thm: order can be no more than one bit
381      *   longer than field cardinality
382      */
383     if (order == NULL || BN_is_zero(order) || BN_is_negative(order)
384         || BN_num_bits(order) > BN_num_bits(group->field) + 1) {
385         ERR_raise(ERR_LIB_EC, EC_R_INVALID_GROUP_ORDER);
386         return 0;
387     }
388 
389     /*-
390      * Unfortunately the cofactor is an optional field in many standards.
391      * Internally, the lib uses 0 cofactor as a marker for "unknown cofactor".
392      * So accept cofactor == NULL or cofactor >= 0.
393      */
394     if (cofactor != NULL && BN_is_negative(cofactor)) {
395         ERR_raise(ERR_LIB_EC, EC_R_UNKNOWN_COFACTOR);
396         return 0;
397     }
398 
399     if (group->generator == NULL) {
400         group->generator = EC_POINT_new(group);
401         if (group->generator == NULL)
402             return 0;
403     }
404     if (!EC_POINT_copy(group->generator, generator))
405         return 0;
406 
407     if (!BN_copy(group->order, order))
408         return 0;
409 
410     /* Either take the provided positive cofactor, or try to compute it */
411     if (cofactor != NULL && !BN_is_zero(cofactor)) {
412         if (!BN_copy(group->cofactor, cofactor))
413             return 0;
414     } else if (!ec_guess_cofactor(group)) {
415         BN_zero(group->cofactor);
416         return 0;
417     }
418 
419     /*
420      * Some groups have an order with
421      * factors of two, which makes the Montgomery setup fail.
422      * |group->mont_data| will be NULL in this case.
423      */
424     if (BN_is_odd(group->order)) {
425         return ec_precompute_mont_data(group);
426     }
427 
428     BN_MONT_CTX_free(group->mont_data);
429     group->mont_data = NULL;
430     return 1;
431 }
432 
EC_GROUP_get0_generator(const EC_GROUP * group)433 const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group)
434 {
435     return group->generator;
436 }
437 
EC_GROUP_get_mont_data(const EC_GROUP * group)438 BN_MONT_CTX *EC_GROUP_get_mont_data(const EC_GROUP *group)
439 {
440     return group->mont_data;
441 }
442 
EC_GROUP_get_order(const EC_GROUP * group,BIGNUM * order,BN_CTX * ctx)443 int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx)
444 {
445     if (group->order == NULL)
446         return 0;
447     if (!BN_copy(order, group->order))
448         return 0;
449 
450     return !BN_is_zero(order);
451 }
452 
EC_GROUP_get0_order(const EC_GROUP * group)453 const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group)
454 {
455     return group->order;
456 }
457 
EC_GROUP_order_bits(const EC_GROUP * group)458 int EC_GROUP_order_bits(const EC_GROUP *group)
459 {
460     return group->meth->group_order_bits(group);
461 }
462 
EC_GROUP_get_cofactor(const EC_GROUP * group,BIGNUM * cofactor,BN_CTX * ctx)463 int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
464                           BN_CTX *ctx)
465 {
466 
467     if (group->cofactor == NULL)
468         return 0;
469     if (!BN_copy(cofactor, group->cofactor))
470         return 0;
471 
472     return !BN_is_zero(group->cofactor);
473 }
474 
EC_GROUP_get0_cofactor(const EC_GROUP * group)475 const BIGNUM *EC_GROUP_get0_cofactor(const EC_GROUP *group)
476 {
477     return group->cofactor;
478 }
479 
EC_GROUP_set_curve_name(EC_GROUP * group,int nid)480 void EC_GROUP_set_curve_name(EC_GROUP *group, int nid)
481 {
482     group->curve_name = nid;
483     group->asn1_flag =
484         (nid != NID_undef)
485         ? OPENSSL_EC_NAMED_CURVE
486         : OPENSSL_EC_EXPLICIT_CURVE;
487 }
488 
EC_GROUP_get_curve_name(const EC_GROUP * group)489 int EC_GROUP_get_curve_name(const EC_GROUP *group)
490 {
491     return group->curve_name;
492 }
493 
EC_GROUP_get0_field(const EC_GROUP * group)494 const BIGNUM *EC_GROUP_get0_field(const EC_GROUP *group)
495 {
496     return group->field;
497 }
498 
EC_GROUP_get_field_type(const EC_GROUP * group)499 int EC_GROUP_get_field_type(const EC_GROUP *group)
500 {
501     return group->meth->field_type;
502 }
503 
EC_GROUP_set_asn1_flag(EC_GROUP * group,int flag)504 void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag)
505 {
506     group->asn1_flag = flag;
507 }
508 
EC_GROUP_get_asn1_flag(const EC_GROUP * group)509 int EC_GROUP_get_asn1_flag(const EC_GROUP *group)
510 {
511     return group->asn1_flag;
512 }
513 
EC_GROUP_set_point_conversion_form(EC_GROUP * group,point_conversion_form_t form)514 void EC_GROUP_set_point_conversion_form(EC_GROUP *group,
515                                         point_conversion_form_t form)
516 {
517     group->asn1_form = form;
518 }
519 
EC_GROUP_get_point_conversion_form(const EC_GROUP * group)520 point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP
521                                                            *group)
522 {
523     return group->asn1_form;
524 }
525 
EC_GROUP_set_seed(EC_GROUP * group,const unsigned char * p,size_t len)526 size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *p, size_t len)
527 {
528     OPENSSL_free(group->seed);
529     group->seed = NULL;
530     group->seed_len = 0;
531 
532     if (!len || !p)
533         return 1;
534 
535     if ((group->seed = OPENSSL_malloc(len)) == NULL) {
536         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
537         return 0;
538     }
539     memcpy(group->seed, p, len);
540     group->seed_len = len;
541 
542     return len;
543 }
544 
EC_GROUP_get0_seed(const EC_GROUP * group)545 unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group)
546 {
547     return group->seed;
548 }
549 
EC_GROUP_get_seed_len(const EC_GROUP * group)550 size_t EC_GROUP_get_seed_len(const EC_GROUP *group)
551 {
552     return group->seed_len;
553 }
554 
EC_GROUP_set_curve(EC_GROUP * group,const BIGNUM * p,const BIGNUM * a,const BIGNUM * b,BN_CTX * ctx)555 int EC_GROUP_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
556                        const BIGNUM *b, BN_CTX *ctx)
557 {
558     if (group->meth->group_set_curve == 0) {
559         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
560         return 0;
561     }
562     return group->meth->group_set_curve(group, p, a, b, ctx);
563 }
564 
EC_GROUP_get_curve(const EC_GROUP * group,BIGNUM * p,BIGNUM * a,BIGNUM * b,BN_CTX * ctx)565 int EC_GROUP_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b,
566                        BN_CTX *ctx)
567 {
568     if (group->meth->group_get_curve == NULL) {
569         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
570         return 0;
571     }
572     return group->meth->group_get_curve(group, p, a, b, ctx);
573 }
574 
575 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_GROUP_set_curve_GFp(EC_GROUP * group,const BIGNUM * p,const BIGNUM * a,const BIGNUM * b,BN_CTX * ctx)576 int EC_GROUP_set_curve_GFp(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
577                            const BIGNUM *b, BN_CTX *ctx)
578 {
579     return EC_GROUP_set_curve(group, p, a, b, ctx);
580 }
581 
EC_GROUP_get_curve_GFp(const EC_GROUP * group,BIGNUM * p,BIGNUM * a,BIGNUM * b,BN_CTX * ctx)582 int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
583                            BIGNUM *b, BN_CTX *ctx)
584 {
585     return EC_GROUP_get_curve(group, p, a, b, ctx);
586 }
587 
588 # ifndef OPENSSL_NO_EC2M
EC_GROUP_set_curve_GF2m(EC_GROUP * group,const BIGNUM * p,const BIGNUM * a,const BIGNUM * b,BN_CTX * ctx)589 int EC_GROUP_set_curve_GF2m(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
590                             const BIGNUM *b, BN_CTX *ctx)
591 {
592     return EC_GROUP_set_curve(group, p, a, b, ctx);
593 }
594 
EC_GROUP_get_curve_GF2m(const EC_GROUP * group,BIGNUM * p,BIGNUM * a,BIGNUM * b,BN_CTX * ctx)595 int EC_GROUP_get_curve_GF2m(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
596                             BIGNUM *b, BN_CTX *ctx)
597 {
598     return EC_GROUP_get_curve(group, p, a, b, ctx);
599 }
600 # endif
601 #endif
602 
EC_GROUP_get_degree(const EC_GROUP * group)603 int EC_GROUP_get_degree(const EC_GROUP *group)
604 {
605     if (group->meth->group_get_degree == 0) {
606         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
607         return 0;
608     }
609     return group->meth->group_get_degree(group);
610 }
611 
EC_GROUP_check_discriminant(const EC_GROUP * group,BN_CTX * ctx)612 int EC_GROUP_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
613 {
614     if (group->meth->group_check_discriminant == 0) {
615         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
616         return 0;
617     }
618     return group->meth->group_check_discriminant(group, ctx);
619 }
620 
EC_GROUP_cmp(const EC_GROUP * a,const EC_GROUP * b,BN_CTX * ctx)621 int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
622 {
623     int r = 0;
624     BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
625 #ifndef FIPS_MODULE
626     BN_CTX *ctx_new = NULL;
627 #endif
628 
629     /* compare the field types */
630     if (EC_GROUP_get_field_type(a) != EC_GROUP_get_field_type(b))
631         return 1;
632     /* compare the curve name (if present in both) */
633     if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
634         EC_GROUP_get_curve_name(a) != EC_GROUP_get_curve_name(b))
635         return 1;
636     if (a->meth->flags & EC_FLAGS_CUSTOM_CURVE)
637         return 0;
638 
639 #ifndef FIPS_MODULE
640     if (ctx == NULL)
641         ctx_new = ctx = BN_CTX_new();
642 #endif
643     if (ctx == NULL)
644         return -1;
645 
646     BN_CTX_start(ctx);
647     a1 = BN_CTX_get(ctx);
648     a2 = BN_CTX_get(ctx);
649     a3 = BN_CTX_get(ctx);
650     b1 = BN_CTX_get(ctx);
651     b2 = BN_CTX_get(ctx);
652     b3 = BN_CTX_get(ctx);
653     if (b3 == NULL) {
654         BN_CTX_end(ctx);
655 #ifndef FIPS_MODULE
656         BN_CTX_free(ctx_new);
657 #endif
658         return -1;
659     }
660 
661     /*
662      * XXX This approach assumes that the external representation of curves
663      * over the same field type is the same.
664      */
665     if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
666         !b->meth->group_get_curve(b, b1, b2, b3, ctx))
667         r = 1;
668 
669     /* return 1 if the curve parameters are different */
670     if (r || BN_cmp(a1, b1) != 0 || BN_cmp(a2, b2) != 0 || BN_cmp(a3, b3) != 0)
671         r = 1;
672 
673     /* XXX EC_POINT_cmp() assumes that the methods are equal */
674     /* return 1 if the generators are different */
675     if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
676                           EC_GROUP_get0_generator(b), ctx) != 0)
677         r = 1;
678 
679     if (!r) {
680         const BIGNUM *ao, *bo, *ac, *bc;
681         /* compare the orders */
682         ao = EC_GROUP_get0_order(a);
683         bo = EC_GROUP_get0_order(b);
684         if (ao == NULL || bo == NULL) {
685             /* return an error if either order is NULL */
686             r = -1;
687             goto end;
688         }
689         if (BN_cmp(ao, bo) != 0) {
690             /* return 1 if orders are different */
691             r = 1;
692             goto end;
693         }
694         /*
695          * It gets here if the curve parameters and generator matched.
696          * Now check the optional cofactors (if both are present).
697          */
698         ac = EC_GROUP_get0_cofactor(a);
699         bc = EC_GROUP_get0_cofactor(b);
700         /* Returns 1 (mismatch) if both cofactors are specified and different */
701         if (!BN_is_zero(ac) && !BN_is_zero(bc) && BN_cmp(ac, bc) != 0)
702             r = 1;
703         /* Returns 0 if the parameters matched */
704     }
705 end:
706     BN_CTX_end(ctx);
707 #ifndef FIPS_MODULE
708     BN_CTX_free(ctx_new);
709 #endif
710     return r;
711 }
712 
713 /* functions for EC_POINT objects */
714 
EC_POINT_new(const EC_GROUP * group)715 EC_POINT *EC_POINT_new(const EC_GROUP *group)
716 {
717     EC_POINT *ret;
718 
719     if (group == NULL) {
720         ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
721         return NULL;
722     }
723     if (group->meth->point_init == NULL) {
724         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
725         return NULL;
726     }
727 
728     ret = OPENSSL_zalloc(sizeof(*ret));
729     if (ret == NULL) {
730         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
731         return NULL;
732     }
733 
734     ret->meth = group->meth;
735     ret->curve_name = group->curve_name;
736 
737     if (!ret->meth->point_init(ret)) {
738         OPENSSL_free(ret);
739         return NULL;
740     }
741 
742     return ret;
743 }
744 
EC_POINT_free(EC_POINT * point)745 void EC_POINT_free(EC_POINT *point)
746 {
747     if (point == NULL)
748         return;
749 
750     if (point->meth->point_finish != 0)
751         point->meth->point_finish(point);
752     OPENSSL_free(point);
753 }
754 
EC_POINT_clear_free(EC_POINT * point)755 void EC_POINT_clear_free(EC_POINT *point)
756 {
757     if (point == NULL)
758         return;
759 
760     if (point->meth->point_clear_finish != 0)
761         point->meth->point_clear_finish(point);
762     else if (point->meth->point_finish != 0)
763         point->meth->point_finish(point);
764     OPENSSL_clear_free(point, sizeof(*point));
765 }
766 
EC_POINT_copy(EC_POINT * dest,const EC_POINT * src)767 int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src)
768 {
769     if (dest->meth->point_copy == 0) {
770         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
771         return 0;
772     }
773     if (dest->meth != src->meth
774             || (dest->curve_name != src->curve_name
775                  && dest->curve_name != 0
776                  && src->curve_name != 0)) {
777         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
778         return 0;
779     }
780     if (dest == src)
781         return 1;
782     return dest->meth->point_copy(dest, src);
783 }
784 
EC_POINT_dup(const EC_POINT * a,const EC_GROUP * group)785 EC_POINT *EC_POINT_dup(const EC_POINT *a, const EC_GROUP *group)
786 {
787     EC_POINT *t;
788     int r;
789 
790     if (a == NULL)
791         return NULL;
792 
793     t = EC_POINT_new(group);
794     if (t == NULL)
795         return NULL;
796     r = EC_POINT_copy(t, a);
797     if (!r) {
798         EC_POINT_free(t);
799         return NULL;
800     }
801     return t;
802 }
803 
804 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINT_method_of(const EC_POINT * point)805 const EC_METHOD *EC_POINT_method_of(const EC_POINT *point)
806 {
807     return point->meth;
808 }
809 #endif
810 
EC_POINT_set_to_infinity(const EC_GROUP * group,EC_POINT * point)811 int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point)
812 {
813     if (group->meth->point_set_to_infinity == 0) {
814         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
815         return 0;
816     }
817     if (group->meth != point->meth) {
818         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
819         return 0;
820     }
821     return group->meth->point_set_to_infinity(group, point);
822 }
823 
824 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP * group,EC_POINT * point,const BIGNUM * x,const BIGNUM * y,const BIGNUM * z,BN_CTX * ctx)825 int EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP *group,
826                                              EC_POINT *point, const BIGNUM *x,
827                                              const BIGNUM *y, const BIGNUM *z,
828                                              BN_CTX *ctx)
829 {
830     if (group->meth->field_type != NID_X9_62_prime_field) {
831         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
832         return 0;
833     }
834     if (!ec_point_is_compat(point, group)) {
835         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
836         return 0;
837     }
838     return ossl_ec_GFp_simple_set_Jprojective_coordinates_GFp(group, point,
839                                                               x, y, z, ctx);
840 }
841 
EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP * group,const EC_POINT * point,BIGNUM * x,BIGNUM * y,BIGNUM * z,BN_CTX * ctx)842 int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group,
843                                              const EC_POINT *point, BIGNUM *x,
844                                              BIGNUM *y, BIGNUM *z,
845                                              BN_CTX *ctx)
846 {
847     if (group->meth->field_type != NID_X9_62_prime_field) {
848         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
849         return 0;
850     }
851     if (!ec_point_is_compat(point, group)) {
852         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
853         return 0;
854     }
855     return ossl_ec_GFp_simple_get_Jprojective_coordinates_GFp(group, point,
856                                                               x, y, z, ctx);
857 }
858 #endif
859 
EC_POINT_set_affine_coordinates(const EC_GROUP * group,EC_POINT * point,const BIGNUM * x,const BIGNUM * y,BN_CTX * ctx)860 int EC_POINT_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point,
861                                     const BIGNUM *x, const BIGNUM *y,
862                                     BN_CTX *ctx)
863 {
864     if (group->meth->point_set_affine_coordinates == NULL) {
865         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
866         return 0;
867     }
868     if (!ec_point_is_compat(point, group)) {
869         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
870         return 0;
871     }
872     if (!group->meth->point_set_affine_coordinates(group, point, x, y, ctx))
873         return 0;
874 
875     if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
876         ERR_raise(ERR_LIB_EC, EC_R_POINT_IS_NOT_ON_CURVE);
877         return 0;
878     }
879     return 1;
880 }
881 
882 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINT_set_affine_coordinates_GFp(const EC_GROUP * group,EC_POINT * point,const BIGNUM * x,const BIGNUM * y,BN_CTX * ctx)883 int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group,
884                                         EC_POINT *point, const BIGNUM *x,
885                                         const BIGNUM *y, BN_CTX *ctx)
886 {
887     return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
888 }
889 
890 # ifndef OPENSSL_NO_EC2M
EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP * group,EC_POINT * point,const BIGNUM * x,const BIGNUM * y,BN_CTX * ctx)891 int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group,
892                                          EC_POINT *point, const BIGNUM *x,
893                                          const BIGNUM *y, BN_CTX *ctx)
894 {
895     return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
896 }
897 # endif
898 #endif
899 
EC_POINT_get_affine_coordinates(const EC_GROUP * group,const EC_POINT * point,BIGNUM * x,BIGNUM * y,BN_CTX * ctx)900 int EC_POINT_get_affine_coordinates(const EC_GROUP *group,
901                                     const EC_POINT *point, BIGNUM *x, BIGNUM *y,
902                                     BN_CTX *ctx)
903 {
904     if (group->meth->point_get_affine_coordinates == NULL) {
905         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
906         return 0;
907     }
908     if (!ec_point_is_compat(point, group)) {
909         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
910         return 0;
911     }
912     if (EC_POINT_is_at_infinity(group, point)) {
913         ERR_raise(ERR_LIB_EC, EC_R_POINT_AT_INFINITY);
914         return 0;
915     }
916     return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
917 }
918 
919 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINT_get_affine_coordinates_GFp(const EC_GROUP * group,const EC_POINT * point,BIGNUM * x,BIGNUM * y,BN_CTX * ctx)920 int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group,
921                                         const EC_POINT *point, BIGNUM *x,
922                                         BIGNUM *y, BN_CTX *ctx)
923 {
924     return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
925 }
926 
927 # ifndef OPENSSL_NO_EC2M
EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP * group,const EC_POINT * point,BIGNUM * x,BIGNUM * y,BN_CTX * ctx)928 int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group,
929                                          const EC_POINT *point, BIGNUM *x,
930                                          BIGNUM *y, BN_CTX *ctx)
931 {
932     return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
933 }
934 # endif
935 #endif
936 
EC_POINT_add(const EC_GROUP * group,EC_POINT * r,const EC_POINT * a,const EC_POINT * b,BN_CTX * ctx)937 int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
938                  const EC_POINT *b, BN_CTX *ctx)
939 {
940     if (group->meth->add == 0) {
941         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
942         return 0;
943     }
944     if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)
945         || !ec_point_is_compat(b, group)) {
946         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
947         return 0;
948     }
949     return group->meth->add(group, r, a, b, ctx);
950 }
951 
EC_POINT_dbl(const EC_GROUP * group,EC_POINT * r,const EC_POINT * a,BN_CTX * ctx)952 int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
953                  BN_CTX *ctx)
954 {
955     if (group->meth->dbl == 0) {
956         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
957         return 0;
958     }
959     if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)) {
960         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
961         return 0;
962     }
963     return group->meth->dbl(group, r, a, ctx);
964 }
965 
EC_POINT_invert(const EC_GROUP * group,EC_POINT * a,BN_CTX * ctx)966 int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx)
967 {
968     if (group->meth->invert == 0) {
969         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
970         return 0;
971     }
972     if (!ec_point_is_compat(a, group)) {
973         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
974         return 0;
975     }
976     return group->meth->invert(group, a, ctx);
977 }
978 
EC_POINT_is_at_infinity(const EC_GROUP * group,const EC_POINT * point)979 int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
980 {
981     if (group->meth->is_at_infinity == 0) {
982         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
983         return 0;
984     }
985     if (!ec_point_is_compat(point, group)) {
986         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
987         return 0;
988     }
989     return group->meth->is_at_infinity(group, point);
990 }
991 
992 /*
993  * Check whether an EC_POINT is on the curve or not. Note that the return
994  * value for this function should NOT be treated as a boolean. Return values:
995  *  1: The point is on the curve
996  *  0: The point is not on the curve
997  * -1: An error occurred
998  */
EC_POINT_is_on_curve(const EC_GROUP * group,const EC_POINT * point,BN_CTX * ctx)999 int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
1000                          BN_CTX *ctx)
1001 {
1002     if (group->meth->is_on_curve == 0) {
1003         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1004         return 0;
1005     }
1006     if (!ec_point_is_compat(point, group)) {
1007         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1008         return 0;
1009     }
1010     return group->meth->is_on_curve(group, point, ctx);
1011 }
1012 
EC_POINT_cmp(const EC_GROUP * group,const EC_POINT * a,const EC_POINT * b,BN_CTX * ctx)1013 int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b,
1014                  BN_CTX *ctx)
1015 {
1016     if (group->meth->point_cmp == 0) {
1017         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1018         return -1;
1019     }
1020     if (!ec_point_is_compat(a, group) || !ec_point_is_compat(b, group)) {
1021         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1022         return -1;
1023     }
1024     return group->meth->point_cmp(group, a, b, ctx);
1025 }
1026 
1027 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINT_make_affine(const EC_GROUP * group,EC_POINT * point,BN_CTX * ctx)1028 int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
1029 {
1030     if (group->meth->make_affine == 0) {
1031         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1032         return 0;
1033     }
1034     if (!ec_point_is_compat(point, group)) {
1035         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1036         return 0;
1037     }
1038     return group->meth->make_affine(group, point, ctx);
1039 }
1040 
EC_POINTs_make_affine(const EC_GROUP * group,size_t num,EC_POINT * points[],BN_CTX * ctx)1041 int EC_POINTs_make_affine(const EC_GROUP *group, size_t num,
1042                           EC_POINT *points[], BN_CTX *ctx)
1043 {
1044     size_t i;
1045 
1046     if (group->meth->points_make_affine == 0) {
1047         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1048         return 0;
1049     }
1050     for (i = 0; i < num; i++) {
1051         if (!ec_point_is_compat(points[i], group)) {
1052             ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1053             return 0;
1054         }
1055     }
1056     return group->meth->points_make_affine(group, num, points, ctx);
1057 }
1058 #endif
1059 
1060 /*
1061  * Functions for point multiplication. If group->meth->mul is 0, we use the
1062  * wNAF-based implementations in ec_mult.c; otherwise we dispatch through
1063  * methods.
1064  */
1065 
1066 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_POINTs_mul(const EC_GROUP * group,EC_POINT * r,const BIGNUM * scalar,size_t num,const EC_POINT * points[],const BIGNUM * scalars[],BN_CTX * ctx)1067 int EC_POINTs_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
1068                   size_t num, const EC_POINT *points[],
1069                   const BIGNUM *scalars[], BN_CTX *ctx)
1070 {
1071     int ret = 0;
1072     size_t i = 0;
1073 #ifndef FIPS_MODULE
1074     BN_CTX *new_ctx = NULL;
1075 #endif
1076 
1077     if (!ec_point_is_compat(r, group)) {
1078         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1079         return 0;
1080     }
1081 
1082     if (scalar == NULL && num == 0)
1083         return EC_POINT_set_to_infinity(group, r);
1084 
1085     for (i = 0; i < num; i++) {
1086         if (!ec_point_is_compat(points[i], group)) {
1087             ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1088             return 0;
1089         }
1090     }
1091 
1092 #ifndef FIPS_MODULE
1093     if (ctx == NULL)
1094         ctx = new_ctx = BN_CTX_secure_new();
1095 #endif
1096     if (ctx == NULL) {
1097         ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
1098         return 0;
1099     }
1100 
1101     if (group->meth->mul != NULL)
1102         ret = group->meth->mul(group, r, scalar, num, points, scalars, ctx);
1103     else
1104         /* use default */
1105         ret = ossl_ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx);
1106 
1107 #ifndef FIPS_MODULE
1108     BN_CTX_free(new_ctx);
1109 #endif
1110     return ret;
1111 }
1112 #endif
1113 
EC_POINT_mul(const EC_GROUP * group,EC_POINT * r,const BIGNUM * g_scalar,const EC_POINT * point,const BIGNUM * p_scalar,BN_CTX * ctx)1114 int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *g_scalar,
1115                  const EC_POINT *point, const BIGNUM *p_scalar, BN_CTX *ctx)
1116 {
1117     int ret = 0;
1118     size_t num;
1119 #ifndef FIPS_MODULE
1120     BN_CTX *new_ctx = NULL;
1121 #endif
1122 
1123     if (!ec_point_is_compat(r, group)
1124         || (point != NULL && !ec_point_is_compat(point, group))) {
1125         ERR_raise(ERR_LIB_EC, EC_R_INCOMPATIBLE_OBJECTS);
1126         return 0;
1127     }
1128 
1129     if (g_scalar == NULL && p_scalar == NULL)
1130         return EC_POINT_set_to_infinity(group, r);
1131 
1132 #ifndef FIPS_MODULE
1133     if (ctx == NULL)
1134         ctx = new_ctx = BN_CTX_secure_new();
1135 #endif
1136     if (ctx == NULL) {
1137         ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
1138         return 0;
1139     }
1140 
1141     num = (point != NULL && p_scalar != NULL) ? 1 : 0;
1142     if (group->meth->mul != NULL)
1143         ret = group->meth->mul(group, r, g_scalar, num, &point, &p_scalar, ctx);
1144     else
1145         /* use default */
1146         ret = ossl_ec_wNAF_mul(group, r, g_scalar, num, &point, &p_scalar, ctx);
1147 
1148 #ifndef FIPS_MODULE
1149     BN_CTX_free(new_ctx);
1150 #endif
1151     return ret;
1152 }
1153 
1154 #ifndef OPENSSL_NO_DEPRECATED_3_0
EC_GROUP_precompute_mult(EC_GROUP * group,BN_CTX * ctx)1155 int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
1156 {
1157     if (group->meth->mul == 0)
1158         /* use default */
1159         return ossl_ec_wNAF_precompute_mult(group, ctx);
1160 
1161     if (group->meth->precompute_mult != 0)
1162         return group->meth->precompute_mult(group, ctx);
1163     else
1164         return 1;               /* nothing to do, so report success */
1165 }
1166 
EC_GROUP_have_precompute_mult(const EC_GROUP * group)1167 int EC_GROUP_have_precompute_mult(const EC_GROUP *group)
1168 {
1169     if (group->meth->mul == 0)
1170         /* use default */
1171         return ossl_ec_wNAF_have_precompute_mult(group);
1172 
1173     if (group->meth->have_precompute_mult != 0)
1174         return group->meth->have_precompute_mult(group);
1175     else
1176         return 0;               /* cannot tell whether precomputation has
1177                                  * been performed */
1178 }
1179 #endif
1180 
1181 /*
1182  * ec_precompute_mont_data sets |group->mont_data| from |group->order| and
1183  * returns one on success. On error it returns zero.
1184  */
ec_precompute_mont_data(EC_GROUP * group)1185 static int ec_precompute_mont_data(EC_GROUP *group)
1186 {
1187     BN_CTX *ctx = BN_CTX_new_ex(group->libctx);
1188     int ret = 0;
1189 
1190     BN_MONT_CTX_free(group->mont_data);
1191     group->mont_data = NULL;
1192 
1193     if (ctx == NULL)
1194         goto err;
1195 
1196     group->mont_data = BN_MONT_CTX_new();
1197     if (group->mont_data == NULL)
1198         goto err;
1199 
1200     if (!BN_MONT_CTX_set(group->mont_data, group->order, ctx)) {
1201         BN_MONT_CTX_free(group->mont_data);
1202         group->mont_data = NULL;
1203         goto err;
1204     }
1205 
1206     ret = 1;
1207 
1208  err:
1209 
1210     BN_CTX_free(ctx);
1211     return ret;
1212 }
1213 
1214 #ifndef FIPS_MODULE
EC_KEY_set_ex_data(EC_KEY * key,int idx,void * arg)1215 int EC_KEY_set_ex_data(EC_KEY *key, int idx, void *arg)
1216 {
1217     return CRYPTO_set_ex_data(&key->ex_data, idx, arg);
1218 }
1219 
EC_KEY_get_ex_data(const EC_KEY * key,int idx)1220 void *EC_KEY_get_ex_data(const EC_KEY *key, int idx)
1221 {
1222     return CRYPTO_get_ex_data(&key->ex_data, idx);
1223 }
1224 #endif
1225 
ossl_ec_group_simple_order_bits(const EC_GROUP * group)1226 int ossl_ec_group_simple_order_bits(const EC_GROUP *group)
1227 {
1228     if (group->order == NULL)
1229         return 0;
1230     return BN_num_bits(group->order);
1231 }
1232 
ec_field_inverse_mod_ord(const EC_GROUP * group,BIGNUM * r,const BIGNUM * x,BN_CTX * ctx)1233 static int ec_field_inverse_mod_ord(const EC_GROUP *group, BIGNUM *r,
1234                                     const BIGNUM *x, BN_CTX *ctx)
1235 {
1236     BIGNUM *e = NULL;
1237     int ret = 0;
1238 #ifndef FIPS_MODULE
1239     BN_CTX *new_ctx = NULL;
1240 #endif
1241 
1242     if (group->mont_data == NULL)
1243         return 0;
1244 
1245 #ifndef FIPS_MODULE
1246     if (ctx == NULL)
1247         ctx = new_ctx = BN_CTX_secure_new();
1248 #endif
1249     if (ctx == NULL)
1250         return 0;
1251 
1252     BN_CTX_start(ctx);
1253     if ((e = BN_CTX_get(ctx)) == NULL)
1254         goto err;
1255 
1256     /*-
1257      * We want inverse in constant time, therefore we utilize the fact
1258      * order must be prime and use Fermats Little Theorem instead.
1259      */
1260     if (!BN_set_word(e, 2))
1261         goto err;
1262     if (!BN_sub(e, group->order, e))
1263         goto err;
1264     /*-
1265      * Exponent e is public.
1266      * No need for scatter-gather or BN_FLG_CONSTTIME.
1267      */
1268     if (!BN_mod_exp_mont(r, x, e, group->order, ctx, group->mont_data))
1269         goto err;
1270 
1271     ret = 1;
1272 
1273  err:
1274     BN_CTX_end(ctx);
1275 #ifndef FIPS_MODULE
1276     BN_CTX_free(new_ctx);
1277 #endif
1278     return ret;
1279 }
1280 
1281 /*-
1282  * Default behavior, if group->meth->field_inverse_mod_ord is NULL:
1283  * - When group->order is even, this function returns an error.
1284  * - When group->order is otherwise composite, the correctness
1285  *   of the output is not guaranteed.
1286  * - When x is outside the range [1, group->order), the correctness
1287  *   of the output is not guaranteed.
1288  * - Otherwise, this function returns the multiplicative inverse in the
1289  *   range [1, group->order).
1290  *
1291  * EC_METHODs must implement their own field_inverse_mod_ord for
1292  * other functionality.
1293  */
ossl_ec_group_do_inverse_ord(const EC_GROUP * group,BIGNUM * res,const BIGNUM * x,BN_CTX * ctx)1294 int ossl_ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,
1295                                  const BIGNUM *x, BN_CTX *ctx)
1296 {
1297     if (group->meth->field_inverse_mod_ord != NULL)
1298         return group->meth->field_inverse_mod_ord(group, res, x, ctx);
1299     else
1300         return ec_field_inverse_mod_ord(group, res, x, ctx);
1301 }
1302 
1303 /*-
1304  * Coordinate blinding for EC_POINT.
1305  *
1306  * The underlying EC_METHOD can optionally implement this function:
1307  * underlying implementations should return 0 on errors, or 1 on
1308  * success.
1309  *
1310  * This wrapper returns 1 in case the underlying EC_METHOD does not
1311  * support coordinate blinding.
1312  */
ossl_ec_point_blind_coordinates(const EC_GROUP * group,EC_POINT * p,BN_CTX * ctx)1313 int ossl_ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p,
1314                                     BN_CTX *ctx)
1315 {
1316     if (group->meth->blind_coordinates == NULL)
1317         return 1; /* ignore if not implemented */
1318 
1319     return group->meth->blind_coordinates(group, p, ctx);
1320 }
1321 
EC_GROUP_get_basis_type(const EC_GROUP * group)1322 int EC_GROUP_get_basis_type(const EC_GROUP *group)
1323 {
1324     int i;
1325 
1326     if (EC_GROUP_get_field_type(group) != NID_X9_62_characteristic_two_field)
1327         /* everything else is currently not supported */
1328         return 0;
1329 
1330     /* Find the last non-zero element of group->poly[] */
1331     for (i = 0;
1332          i < (int)OSSL_NELEM(group->poly) && group->poly[i] != 0;
1333          i++)
1334         continue;
1335 
1336     if (i == 4)
1337         return NID_X9_62_ppBasis;
1338     else if (i == 2)
1339         return NID_X9_62_tpBasis;
1340     else
1341         /* everything else is currently not supported */
1342         return 0;
1343 }
1344 
1345 #ifndef OPENSSL_NO_EC2M
EC_GROUP_get_trinomial_basis(const EC_GROUP * group,unsigned int * k)1346 int EC_GROUP_get_trinomial_basis(const EC_GROUP *group, unsigned int *k)
1347 {
1348     if (group == NULL)
1349         return 0;
1350 
1351     if (EC_GROUP_get_field_type(group) != NID_X9_62_characteristic_two_field
1352         || !((group->poly[0] != 0) && (group->poly[1] != 0)
1353              && (group->poly[2] == 0))) {
1354         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1355         return 0;
1356     }
1357 
1358     if (k)
1359         *k = group->poly[1];
1360 
1361     return 1;
1362 }
1363 
EC_GROUP_get_pentanomial_basis(const EC_GROUP * group,unsigned int * k1,unsigned int * k2,unsigned int * k3)1364 int EC_GROUP_get_pentanomial_basis(const EC_GROUP *group, unsigned int *k1,
1365                                    unsigned int *k2, unsigned int *k3)
1366 {
1367     if (group == NULL)
1368         return 0;
1369 
1370     if (EC_GROUP_get_field_type(group) != NID_X9_62_characteristic_two_field
1371         || !((group->poly[0] != 0) && (group->poly[1] != 0)
1372              && (group->poly[2] != 0) && (group->poly[3] != 0)
1373              && (group->poly[4] == 0))) {
1374         ERR_raise(ERR_LIB_EC, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1375         return 0;
1376     }
1377 
1378     if (k1)
1379         *k1 = group->poly[3];
1380     if (k2)
1381         *k2 = group->poly[2];
1382     if (k3)
1383         *k3 = group->poly[1];
1384 
1385     return 1;
1386 }
1387 #endif
1388 
1389 #ifndef FIPS_MODULE
1390 /*
1391  * Check if the explicit parameters group matches any built-in curves.
1392  *
1393  * We create a copy of the group just built, so that we can remove optional
1394  * fields for the lookup: we do this to avoid the possibility that one of
1395  * the optional parameters is used to force the library into using a less
1396  * performant and less secure EC_METHOD instead of the specialized one.
1397  * In any case, `seed` is not really used in any computation, while a
1398  * cofactor different from the one in the built-in table is just
1399  * mathematically wrong anyway and should not be used.
1400  */
ec_group_explicit_to_named(const EC_GROUP * group,OSSL_LIB_CTX * libctx,const char * propq,BN_CTX * ctx)1401 static EC_GROUP *ec_group_explicit_to_named(const EC_GROUP *group,
1402                                             OSSL_LIB_CTX *libctx,
1403                                             const char *propq,
1404                                             BN_CTX *ctx)
1405 {
1406     EC_GROUP *ret_group = NULL, *dup = NULL;
1407     int curve_name_nid;
1408 
1409     const EC_POINT *point = EC_GROUP_get0_generator(group);
1410     const BIGNUM *order = EC_GROUP_get0_order(group);
1411     int no_seed = (EC_GROUP_get0_seed(group) == NULL);
1412 
1413     if ((dup = EC_GROUP_dup(group)) == NULL
1414             || EC_GROUP_set_seed(dup, NULL, 0) != 1
1415             || !EC_GROUP_set_generator(dup, point, order, NULL))
1416         goto err;
1417     if ((curve_name_nid = ossl_ec_curve_nid_from_params(dup, ctx)) != NID_undef) {
1418         /*
1419          * The input explicit parameters successfully matched one of the
1420          * built-in curves: often for built-in curves we have specialized
1421          * methods with better performance and hardening.
1422          *
1423          * In this case we replace the `EC_GROUP` created through explicit
1424          * parameters with one created from a named group.
1425          */
1426 
1427 # ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
1428         /*
1429          * NID_wap_wsg_idm_ecid_wtls12 and NID_secp224r1 are both aliases for
1430          * the same curve, we prefer the SECP nid when matching explicit
1431          * parameters as that is associated with a specialized EC_METHOD.
1432          */
1433         if (curve_name_nid == NID_wap_wsg_idm_ecid_wtls12)
1434             curve_name_nid = NID_secp224r1;
1435 # endif /* !def(OPENSSL_NO_EC_NISTP_64_GCC_128) */
1436 
1437         ret_group = EC_GROUP_new_by_curve_name_ex(libctx, propq, curve_name_nid);
1438         if (ret_group == NULL)
1439             goto err;
1440 
1441         /*
1442          * Set the flag so that EC_GROUPs created from explicit parameters are
1443          * serialized using explicit parameters by default.
1444          */
1445         EC_GROUP_set_asn1_flag(ret_group, OPENSSL_EC_EXPLICIT_CURVE);
1446 
1447         /*
1448          * If the input params do not contain the optional seed field we make
1449          * sure it is not added to the returned group.
1450          *
1451          * The seed field is not really used inside libcrypto anyway, and
1452          * adding it to parsed explicit parameter keys would alter their DER
1453          * encoding output (because of the extra field) which could impact
1454          * applications fingerprinting keys by their DER encoding.
1455          */
1456         if (no_seed) {
1457             if (EC_GROUP_set_seed(ret_group, NULL, 0) != 1)
1458                 goto err;
1459         }
1460     } else {
1461         ret_group = (EC_GROUP *)group;
1462     }
1463     EC_GROUP_free(dup);
1464     return ret_group;
1465 err:
1466     EC_GROUP_free(dup);
1467     EC_GROUP_free(ret_group);
1468     return NULL;
1469 }
1470 #endif /* FIPS_MODULE */
1471 
group_new_from_name(const OSSL_PARAM * p,OSSL_LIB_CTX * libctx,const char * propq)1472 static EC_GROUP *group_new_from_name(const OSSL_PARAM *p,
1473                                      OSSL_LIB_CTX *libctx, const char *propq)
1474 {
1475     int ok = 0, nid;
1476     const char *curve_name = NULL;
1477 
1478     switch (p->data_type) {
1479     case OSSL_PARAM_UTF8_STRING:
1480         /* The OSSL_PARAM functions have no support for this */
1481         curve_name = p->data;
1482         ok = (curve_name != NULL);
1483         break;
1484     case OSSL_PARAM_UTF8_PTR:
1485         ok = OSSL_PARAM_get_utf8_ptr(p, &curve_name);
1486         break;
1487     }
1488 
1489     if (ok) {
1490         nid = ossl_ec_curve_name2nid(curve_name);
1491         if (nid == NID_undef) {
1492             ERR_raise(ERR_LIB_EC, EC_R_INVALID_CURVE);
1493             return NULL;
1494         } else {
1495             return EC_GROUP_new_by_curve_name_ex(libctx, propq, nid);
1496         }
1497     }
1498     return NULL;
1499 }
1500 
1501 /* These parameters can be set directly into an EC_GROUP */
ossl_ec_group_set_params(EC_GROUP * group,const OSSL_PARAM params[])1502 int ossl_ec_group_set_params(EC_GROUP *group, const OSSL_PARAM params[])
1503 {
1504     int encoding_flag = -1, format = -1;
1505     const OSSL_PARAM *p;
1506 
1507     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_POINT_CONVERSION_FORMAT);
1508     if (p != NULL) {
1509         if (!ossl_ec_pt_format_param2id(p, &format)) {
1510             ECerr(0, EC_R_INVALID_FORM);
1511             return 0;
1512         }
1513         EC_GROUP_set_point_conversion_form(group, format);
1514     }
1515 
1516     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_ENCODING);
1517     if (p != NULL) {
1518         if (!ossl_ec_encoding_param2id(p, &encoding_flag)) {
1519             ECerr(0, EC_R_INVALID_FORM);
1520             return 0;
1521         }
1522         EC_GROUP_set_asn1_flag(group, encoding_flag);
1523     }
1524     /* Optional seed */
1525     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_SEED);
1526     if (p != NULL) {
1527         /* The seed is allowed to be NULL */
1528         if (p->data_type != OSSL_PARAM_OCTET_STRING
1529             || !EC_GROUP_set_seed(group, p->data, p->data_size)) {
1530             ECerr(0, EC_R_INVALID_SEED);
1531             return 0;
1532         }
1533     }
1534     return 1;
1535 }
1536 
EC_GROUP_new_from_params(const OSSL_PARAM params[],OSSL_LIB_CTX * libctx,const char * propq)1537 EC_GROUP *EC_GROUP_new_from_params(const OSSL_PARAM params[],
1538                                    OSSL_LIB_CTX *libctx, const char *propq)
1539 {
1540     const OSSL_PARAM *ptmp;
1541     EC_GROUP *group = NULL;
1542 
1543 #ifndef FIPS_MODULE
1544     const OSSL_PARAM *pa, *pb;
1545     int ok = 0;
1546     EC_GROUP *named_group = NULL;
1547     BIGNUM *p = NULL, *a = NULL, *b = NULL, *order = NULL, *cofactor = NULL;
1548     EC_POINT *point = NULL;
1549     int field_bits = 0;
1550     int is_prime_field = 1;
1551     BN_CTX *bnctx = NULL;
1552     const unsigned char *buf = NULL;
1553     int encoding_flag = -1;
1554 #endif
1555 
1556     /* This is the simple named group case */
1557     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_GROUP_NAME);
1558     if (ptmp != NULL) {
1559         int decoded = 0;
1560 
1561         if ((group = group_new_from_name(ptmp, libctx, propq)) == NULL)
1562             return NULL;
1563         if (!ossl_ec_group_set_params(group, params)) {
1564             EC_GROUP_free(group);
1565             return NULL;
1566         }
1567 
1568         ptmp = OSSL_PARAM_locate_const(params,
1569                                        OSSL_PKEY_PARAM_EC_DECODED_FROM_EXPLICIT_PARAMS);
1570         if (ptmp != NULL && !OSSL_PARAM_get_int(ptmp, &decoded)) {
1571             ERR_raise(ERR_LIB_EC, EC_R_WRONG_CURVE_PARAMETERS);
1572             EC_GROUP_free(group);
1573             return NULL;
1574         }
1575         group->decoded_from_explicit_params = decoded > 0;
1576         return group;
1577     }
1578 #ifdef FIPS_MODULE
1579     ERR_raise(ERR_LIB_EC, EC_R_EXPLICIT_PARAMS_NOT_SUPPORTED);
1580     return NULL;
1581 #else
1582     /* If it gets here then we are trying explicit parameters */
1583     bnctx = BN_CTX_new_ex(libctx);
1584     if (bnctx == NULL) {
1585         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
1586         return 0;
1587     }
1588     BN_CTX_start(bnctx);
1589 
1590     p = BN_CTX_get(bnctx);
1591     a = BN_CTX_get(bnctx);
1592     b = BN_CTX_get(bnctx);
1593     order = BN_CTX_get(bnctx);
1594     if (order == NULL) {
1595         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
1596         goto err;
1597     }
1598 
1599     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_FIELD_TYPE);
1600     if (ptmp == NULL || ptmp->data_type != OSSL_PARAM_UTF8_STRING) {
1601         ERR_raise(ERR_LIB_EC, EC_R_INVALID_FIELD);
1602         goto err;
1603     }
1604     if (OPENSSL_strcasecmp(ptmp->data, SN_X9_62_prime_field) == 0) {
1605         is_prime_field = 1;
1606     } else if (OPENSSL_strcasecmp(ptmp->data,
1607                                   SN_X9_62_characteristic_two_field) == 0) {
1608         is_prime_field = 0;
1609     } else {
1610         /* Invalid field */
1611         ERR_raise(ERR_LIB_EC, EC_R_UNSUPPORTED_FIELD);
1612         goto err;
1613     }
1614 
1615     pa = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_A);
1616     if (!OSSL_PARAM_get_BN(pa, &a)) {
1617         ERR_raise(ERR_LIB_EC, EC_R_INVALID_A);
1618         goto err;
1619     }
1620     pb = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_B);
1621     if (!OSSL_PARAM_get_BN(pb, &b)) {
1622         ERR_raise(ERR_LIB_EC, EC_R_INVALID_B);
1623         goto err;
1624     }
1625 
1626     /* extract the prime number or irreducible polynomial */
1627     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_P);
1628     if (!OSSL_PARAM_get_BN(ptmp, &p)) {
1629         ERR_raise(ERR_LIB_EC, EC_R_INVALID_P);
1630         goto err;
1631     }
1632 
1633     if (is_prime_field) {
1634         if (BN_is_negative(p) || BN_is_zero(p)) {
1635             ERR_raise(ERR_LIB_EC, EC_R_INVALID_P);
1636             goto err;
1637         }
1638         field_bits = BN_num_bits(p);
1639         if (field_bits > OPENSSL_ECC_MAX_FIELD_BITS) {
1640             ERR_raise(ERR_LIB_EC, EC_R_FIELD_TOO_LARGE);
1641             goto err;
1642         }
1643 
1644         /* create the EC_GROUP structure */
1645         group = EC_GROUP_new_curve_GFp(p, a, b, bnctx);
1646     } else {
1647 # ifdef OPENSSL_NO_EC2M
1648         ERR_raise(ERR_LIB_EC, EC_R_GF2M_NOT_SUPPORTED);
1649         goto err;
1650 # else
1651         /* create the EC_GROUP structure */
1652         group = EC_GROUP_new_curve_GF2m(p, a, b, NULL);
1653         if (group != NULL) {
1654             field_bits = EC_GROUP_get_degree(group);
1655             if (field_bits > OPENSSL_ECC_MAX_FIELD_BITS) {
1656                 ERR_raise(ERR_LIB_EC, EC_R_FIELD_TOO_LARGE);
1657                 goto err;
1658             }
1659         }
1660 # endif /* OPENSSL_NO_EC2M */
1661     }
1662 
1663     if (group == NULL) {
1664         ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
1665         goto err;
1666     }
1667 
1668     /* Optional seed */
1669     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_SEED);
1670     if (ptmp != NULL) {
1671         if (ptmp->data_type != OSSL_PARAM_OCTET_STRING) {
1672             ERR_raise(ERR_LIB_EC, EC_R_INVALID_SEED);
1673             goto err;
1674         }
1675         if (!EC_GROUP_set_seed(group, ptmp->data, ptmp->data_size))
1676             goto err;
1677     }
1678 
1679     /* generator base point */
1680     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_GENERATOR);
1681     if (ptmp == NULL
1682         || ptmp->data_type != OSSL_PARAM_OCTET_STRING) {
1683         ERR_raise(ERR_LIB_EC, EC_R_INVALID_GENERATOR);
1684         goto err;
1685     }
1686     buf = (const unsigned char *)(ptmp->data);
1687     if ((point = EC_POINT_new(group)) == NULL)
1688         goto err;
1689     EC_GROUP_set_point_conversion_form(group,
1690                                        (point_conversion_form_t)buf[0] & ~0x01);
1691     if (!EC_POINT_oct2point(group, point, buf, ptmp->data_size, bnctx)) {
1692         ERR_raise(ERR_LIB_EC, EC_R_INVALID_GENERATOR);
1693         goto err;
1694     }
1695 
1696     /* order */
1697     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_ORDER);
1698     if (!OSSL_PARAM_get_BN(ptmp, &order)
1699         || (BN_is_negative(order) || BN_is_zero(order))
1700         || (BN_num_bits(order) > (int)field_bits + 1)) { /* Hasse bound */
1701         ERR_raise(ERR_LIB_EC, EC_R_INVALID_GROUP_ORDER);
1702         goto err;
1703     }
1704 
1705     /* Optional cofactor */
1706     ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_COFACTOR);
1707     if (ptmp != NULL) {
1708         cofactor = BN_CTX_get(bnctx);
1709         if (cofactor == NULL || !OSSL_PARAM_get_BN(ptmp, &cofactor)) {
1710             ERR_raise(ERR_LIB_EC, EC_R_INVALID_COFACTOR);
1711             goto err;
1712         }
1713     }
1714 
1715     /* set the generator, order and cofactor (if present) */
1716     if (!EC_GROUP_set_generator(group, point, order, cofactor)) {
1717         ERR_raise(ERR_LIB_EC, EC_R_INVALID_GENERATOR);
1718         goto err;
1719     }
1720 
1721     named_group = ec_group_explicit_to_named(group, libctx, propq, bnctx);
1722     if (named_group == NULL) {
1723         ERR_raise(ERR_LIB_EC, EC_R_INVALID_NAMED_GROUP_CONVERSION);
1724         goto err;
1725     }
1726     if (named_group == group) {
1727         /*
1728          * If we did not find a named group then the encoding should be explicit
1729          * if it was specified
1730          */
1731         ptmp = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_ENCODING);
1732         if (ptmp != NULL
1733             && !ossl_ec_encoding_param2id(ptmp, &encoding_flag)) {
1734             ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
1735             goto err;
1736         }
1737         if (encoding_flag == OPENSSL_EC_NAMED_CURVE) {
1738             ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
1739             goto err;
1740         }
1741         EC_GROUP_set_asn1_flag(group, OPENSSL_EC_EXPLICIT_CURVE);
1742     } else {
1743         EC_GROUP_free(group);
1744         group = named_group;
1745     }
1746     /* We've imported the group from explicit parameters, set it so. */
1747     group->decoded_from_explicit_params = 1;
1748     ok = 1;
1749  err:
1750     if (!ok) {
1751         EC_GROUP_free(group);
1752         group = NULL;
1753     }
1754     EC_POINT_free(point);
1755     BN_CTX_end(bnctx);
1756     BN_CTX_free(bnctx);
1757 
1758     return group;
1759 #endif /* FIPS_MODULE */
1760 }
1761