1160814Ssimon/* crypto/ecdsa/ecs_ossl.c */ 2160814Ssimon/* 3160814Ssimon * Written by Nils Larsch for the OpenSSL project 4160814Ssimon */ 5160814Ssimon/* ==================================================================== 6160814Ssimon * Copyright (c) 1998-2004 The OpenSSL Project. All rights reserved. 7160814Ssimon * 8160814Ssimon * Redistribution and use in source and binary forms, with or without 9160814Ssimon * modification, are permitted provided that the following conditions 10160814Ssimon * are met: 11160814Ssimon * 12160814Ssimon * 1. Redistributions of source code must retain the above copyright 13296465Sdelphij * notice, this list of conditions and the following disclaimer. 14160814Ssimon * 15160814Ssimon * 2. Redistributions in binary form must reproduce the above copyright 16160814Ssimon * notice, this list of conditions and the following disclaimer in 17160814Ssimon * the documentation and/or other materials provided with the 18160814Ssimon * distribution. 19160814Ssimon * 20160814Ssimon * 3. All advertising materials mentioning features or use of this 21160814Ssimon * software must display the following acknowledgment: 22160814Ssimon * "This product includes software developed by the OpenSSL Project 23160814Ssimon * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24160814Ssimon * 25160814Ssimon * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26160814Ssimon * endorse or promote products derived from this software without 27160814Ssimon * prior written permission. For written permission, please contact 28160814Ssimon * openssl-core@OpenSSL.org. 29160814Ssimon * 30160814Ssimon * 5. Products derived from this software may not be called "OpenSSL" 31160814Ssimon * nor may "OpenSSL" appear in their names without prior written 32160814Ssimon * permission of the OpenSSL Project. 33160814Ssimon * 34160814Ssimon * 6. Redistributions of any form whatsoever must retain the following 35160814Ssimon * acknowledgment: 36160814Ssimon * "This product includes software developed by the OpenSSL Project 37160814Ssimon * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38160814Ssimon * 39160814Ssimon * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40160814Ssimon * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41160814Ssimon * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42160814Ssimon * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43160814Ssimon * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44160814Ssimon * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45160814Ssimon * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46160814Ssimon * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47160814Ssimon * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48160814Ssimon * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49160814Ssimon * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50160814Ssimon * OF THE POSSIBILITY OF SUCH DAMAGE. 51160814Ssimon * ==================================================================== 52160814Ssimon * 53160814Ssimon * This product includes cryptographic software written by Eric Young 54160814Ssimon * (eay@cryptsoft.com). This product includes software written by Tim 55160814Ssimon * Hudson (tjh@cryptsoft.com). 56160814Ssimon * 57160814Ssimon */ 58160814Ssimon 59160814Ssimon#include "ecs_locl.h" 60160814Ssimon#include <openssl/err.h> 61160814Ssimon#include <openssl/obj_mac.h> 62160814Ssimon#include <openssl/bn.h> 63160814Ssimon 64296465Sdelphijstatic ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, 65296465Sdelphij const BIGNUM *, const BIGNUM *, 66296465Sdelphij EC_KEY *eckey); 67296465Sdelphijstatic int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, 68296465Sdelphij BIGNUM **rp); 69296465Sdelphijstatic int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, 70296465Sdelphij const ECDSA_SIG *sig, EC_KEY *eckey); 71160814Ssimon 72160814Ssimonstatic ECDSA_METHOD openssl_ecdsa_meth = { 73296465Sdelphij "OpenSSL ECDSA method", 74296465Sdelphij ecdsa_do_sign, 75296465Sdelphij ecdsa_sign_setup, 76296465Sdelphij ecdsa_do_verify, 77160814Ssimon#if 0 78296465Sdelphij NULL, /* init */ 79296465Sdelphij NULL, /* finish */ 80160814Ssimon#endif 81296465Sdelphij 0, /* flags */ 82296465Sdelphij NULL /* app_data */ 83160814Ssimon}; 84160814Ssimon 85160814Ssimonconst ECDSA_METHOD *ECDSA_OpenSSL(void) 86160814Ssimon{ 87296465Sdelphij return &openssl_ecdsa_meth; 88160814Ssimon} 89160814Ssimon 90160814Ssimonstatic int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, 91296465Sdelphij BIGNUM **rp) 92160814Ssimon{ 93296465Sdelphij BN_CTX *ctx = NULL; 94296465Sdelphij BIGNUM *k = NULL, *r = NULL, *order = NULL, *X = NULL; 95296465Sdelphij EC_POINT *tmp_point = NULL; 96296465Sdelphij const EC_GROUP *group; 97296465Sdelphij int ret = 0; 98160814Ssimon 99296465Sdelphij if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) { 100296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER); 101296465Sdelphij return 0; 102296465Sdelphij } 103160814Ssimon 104296465Sdelphij if (ctx_in == NULL) { 105296465Sdelphij if ((ctx = BN_CTX_new()) == NULL) { 106296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); 107296465Sdelphij return 0; 108296465Sdelphij } 109296465Sdelphij } else 110296465Sdelphij ctx = ctx_in; 111160814Ssimon 112296465Sdelphij k = BN_new(); /* this value is later returned in *kinvp */ 113296465Sdelphij r = BN_new(); /* this value is later returned in *rp */ 114296465Sdelphij order = BN_new(); 115296465Sdelphij X = BN_new(); 116296465Sdelphij if (!k || !r || !order || !X) { 117296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); 118296465Sdelphij goto err; 119296465Sdelphij } 120296465Sdelphij if ((tmp_point = EC_POINT_new(group)) == NULL) { 121296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); 122296465Sdelphij goto err; 123296465Sdelphij } 124296465Sdelphij if (!EC_GROUP_get_order(group, order, ctx)) { 125296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); 126296465Sdelphij goto err; 127296465Sdelphij } 128160814Ssimon 129296465Sdelphij do { 130296465Sdelphij /* get random k */ 131296465Sdelphij do 132296465Sdelphij if (!BN_rand_range(k, order)) { 133296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, 134296465Sdelphij ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); 135296465Sdelphij goto err; 136296465Sdelphij } 137296465Sdelphij while (BN_is_zero(k)) ; 138237998Sjkim 139296465Sdelphij /* 140296465Sdelphij * We do not want timing information to leak the length of k, so we 141296465Sdelphij * compute G*k using an equivalent scalar of fixed bit-length. 142296465Sdelphij */ 143237998Sjkim 144296465Sdelphij if (!BN_add(k, k, order)) 145296465Sdelphij goto err; 146296465Sdelphij if (BN_num_bits(k) <= BN_num_bits(order)) 147296465Sdelphij if (!BN_add(k, k, order)) 148296465Sdelphij goto err; 149160814Ssimon 150296465Sdelphij /* compute r the x-coordinate of generator * k */ 151296465Sdelphij if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) { 152296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); 153296465Sdelphij goto err; 154296465Sdelphij } 155296465Sdelphij if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == 156296465Sdelphij NID_X9_62_prime_field) { 157296465Sdelphij if (!EC_POINT_get_affine_coordinates_GFp 158296465Sdelphij (group, tmp_point, X, NULL, ctx)) { 159296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); 160296465Sdelphij goto err; 161296465Sdelphij } 162296465Sdelphij } else { /* NID_X9_62_characteristic_two_field */ 163296465Sdelphij 164296465Sdelphij if (!EC_POINT_get_affine_coordinates_GF2m(group, 165296465Sdelphij tmp_point, X, NULL, 166296465Sdelphij ctx)) { 167296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); 168296465Sdelphij goto err; 169296465Sdelphij } 170296465Sdelphij } 171296465Sdelphij if (!BN_nnmod(r, X, order, ctx)) { 172296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); 173296465Sdelphij goto err; 174296465Sdelphij } 175296465Sdelphij } 176296465Sdelphij while (BN_is_zero(r)); 177296465Sdelphij 178296465Sdelphij /* compute the inverse of k */ 179296465Sdelphij if (!BN_mod_inverse(k, k, order, ctx)) { 180296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); 181296465Sdelphij goto err; 182296465Sdelphij } 183296465Sdelphij /* clear old values if necessary */ 184296465Sdelphij if (*rp != NULL) 185296465Sdelphij BN_clear_free(*rp); 186296465Sdelphij if (*kinvp != NULL) 187296465Sdelphij BN_clear_free(*kinvp); 188296465Sdelphij /* save the pre-computed values */ 189296465Sdelphij *rp = r; 190296465Sdelphij *kinvp = k; 191296465Sdelphij ret = 1; 192296465Sdelphij err: 193296465Sdelphij if (!ret) { 194296465Sdelphij if (k != NULL) 195296465Sdelphij BN_clear_free(k); 196296465Sdelphij if (r != NULL) 197296465Sdelphij BN_clear_free(r); 198296465Sdelphij } 199296465Sdelphij if (ctx_in == NULL) 200296465Sdelphij BN_CTX_free(ctx); 201296465Sdelphij if (order != NULL) 202296465Sdelphij BN_free(order); 203296465Sdelphij if (tmp_point != NULL) 204296465Sdelphij EC_POINT_free(tmp_point); 205296465Sdelphij if (X) 206296465Sdelphij BN_clear_free(X); 207296465Sdelphij return (ret); 208160814Ssimon} 209160814Ssimon 210296465Sdelphijstatic ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, 211296465Sdelphij const BIGNUM *in_kinv, const BIGNUM *in_r, 212296465Sdelphij EC_KEY *eckey) 213160814Ssimon{ 214296465Sdelphij int ok = 0, i; 215296465Sdelphij BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL, *order = NULL; 216296465Sdelphij const BIGNUM *ckinv; 217296465Sdelphij BN_CTX *ctx = NULL; 218296465Sdelphij const EC_GROUP *group; 219296465Sdelphij ECDSA_SIG *ret; 220296465Sdelphij ECDSA_DATA *ecdsa; 221296465Sdelphij const BIGNUM *priv_key; 222160814Ssimon 223296465Sdelphij ecdsa = ecdsa_check(eckey); 224296465Sdelphij group = EC_KEY_get0_group(eckey); 225296465Sdelphij priv_key = EC_KEY_get0_private_key(eckey); 226160814Ssimon 227296465Sdelphij if (group == NULL || priv_key == NULL || ecdsa == NULL) { 228296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER); 229296465Sdelphij return NULL; 230296465Sdelphij } 231160814Ssimon 232296465Sdelphij ret = ECDSA_SIG_new(); 233296465Sdelphij if (!ret) { 234296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); 235296465Sdelphij return NULL; 236296465Sdelphij } 237296465Sdelphij s = ret->s; 238160814Ssimon 239296465Sdelphij if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL || 240296465Sdelphij (tmp = BN_new()) == NULL || (m = BN_new()) == NULL) { 241296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); 242296465Sdelphij goto err; 243296465Sdelphij } 244160814Ssimon 245296465Sdelphij if (!EC_GROUP_get_order(group, order, ctx)) { 246296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_EC_LIB); 247296465Sdelphij goto err; 248296465Sdelphij } 249296465Sdelphij i = BN_num_bits(order); 250296465Sdelphij /* 251296465Sdelphij * Need to truncate digest if it is too long: first truncate whole bytes. 252296465Sdelphij */ 253296465Sdelphij if (8 * dgst_len > i) 254296465Sdelphij dgst_len = (i + 7) / 8; 255296465Sdelphij if (!BN_bin2bn(dgst, dgst_len, m)) { 256296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); 257296465Sdelphij goto err; 258296465Sdelphij } 259296465Sdelphij /* If still too long truncate remaining bits with a shift */ 260296465Sdelphij if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) { 261296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); 262296465Sdelphij goto err; 263296465Sdelphij } 264296465Sdelphij do { 265296465Sdelphij if (in_kinv == NULL || in_r == NULL) { 266296465Sdelphij if (!ECDSA_sign_setup(eckey, ctx, &kinv, &ret->r)) { 267296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_ECDSA_LIB); 268296465Sdelphij goto err; 269296465Sdelphij } 270296465Sdelphij ckinv = kinv; 271296465Sdelphij } else { 272296465Sdelphij ckinv = in_kinv; 273296465Sdelphij if (BN_copy(ret->r, in_r) == NULL) { 274296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); 275296465Sdelphij goto err; 276296465Sdelphij } 277296465Sdelphij } 278160814Ssimon 279296465Sdelphij if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) { 280296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); 281296465Sdelphij goto err; 282296465Sdelphij } 283296465Sdelphij if (!BN_mod_add_quick(s, tmp, m, order)) { 284296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); 285296465Sdelphij goto err; 286296465Sdelphij } 287296465Sdelphij if (!BN_mod_mul(s, s, ckinv, order, ctx)) { 288296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); 289296465Sdelphij goto err; 290296465Sdelphij } 291296465Sdelphij if (BN_is_zero(s)) { 292296465Sdelphij /* 293296465Sdelphij * if kinv and r have been supplied by the caller don't to 294296465Sdelphij * generate new kinv and r values 295296465Sdelphij */ 296296465Sdelphij if (in_kinv != NULL && in_r != NULL) { 297296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, 298296465Sdelphij ECDSA_R_NEED_NEW_SETUP_VALUES); 299296465Sdelphij goto err; 300296465Sdelphij } 301296465Sdelphij } else 302296465Sdelphij /* s != 0 => we have a valid signature */ 303296465Sdelphij break; 304296465Sdelphij } 305296465Sdelphij while (1); 306296465Sdelphij 307296465Sdelphij ok = 1; 308296465Sdelphij err: 309296465Sdelphij if (!ok) { 310296465Sdelphij ECDSA_SIG_free(ret); 311296465Sdelphij ret = NULL; 312296465Sdelphij } 313296465Sdelphij if (ctx) 314296465Sdelphij BN_CTX_free(ctx); 315296465Sdelphij if (m) 316296465Sdelphij BN_clear_free(m); 317296465Sdelphij if (tmp) 318296465Sdelphij BN_clear_free(tmp); 319296465Sdelphij if (order) 320296465Sdelphij BN_free(order); 321296465Sdelphij if (kinv) 322296465Sdelphij BN_clear_free(kinv); 323296465Sdelphij return ret; 324160814Ssimon} 325160814Ssimon 326160814Ssimonstatic int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, 327296465Sdelphij const ECDSA_SIG *sig, EC_KEY *eckey) 328160814Ssimon{ 329296465Sdelphij int ret = -1, i; 330296465Sdelphij BN_CTX *ctx; 331296465Sdelphij BIGNUM *order, *u1, *u2, *m, *X; 332296465Sdelphij EC_POINT *point = NULL; 333296465Sdelphij const EC_GROUP *group; 334296465Sdelphij const EC_POINT *pub_key; 335160814Ssimon 336296465Sdelphij /* check input values */ 337296465Sdelphij if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL || 338296465Sdelphij (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) { 339296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_MISSING_PARAMETERS); 340296465Sdelphij return -1; 341296465Sdelphij } 342160814Ssimon 343296465Sdelphij ctx = BN_CTX_new(); 344296465Sdelphij if (!ctx) { 345296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); 346296465Sdelphij return -1; 347296465Sdelphij } 348296465Sdelphij BN_CTX_start(ctx); 349296465Sdelphij order = BN_CTX_get(ctx); 350296465Sdelphij u1 = BN_CTX_get(ctx); 351296465Sdelphij u2 = BN_CTX_get(ctx); 352296465Sdelphij m = BN_CTX_get(ctx); 353296465Sdelphij X = BN_CTX_get(ctx); 354296465Sdelphij if (!X) { 355296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 356296465Sdelphij goto err; 357296465Sdelphij } 358160814Ssimon 359296465Sdelphij if (!EC_GROUP_get_order(group, order, ctx)) { 360296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); 361296465Sdelphij goto err; 362296465Sdelphij } 363160814Ssimon 364296465Sdelphij if (BN_is_zero(sig->r) || BN_is_negative(sig->r) || 365296465Sdelphij BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) || 366296465Sdelphij BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) { 367296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE); 368296465Sdelphij ret = 0; /* signature is invalid */ 369296465Sdelphij goto err; 370296465Sdelphij } 371296465Sdelphij /* calculate tmp1 = inv(S) mod order */ 372296465Sdelphij if (!BN_mod_inverse(u2, sig->s, order, ctx)) { 373296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 374296465Sdelphij goto err; 375296465Sdelphij } 376296465Sdelphij /* digest -> m */ 377296465Sdelphij i = BN_num_bits(order); 378296465Sdelphij /* 379296465Sdelphij * Need to truncate digest if it is too long: first truncate whole bytes. 380296465Sdelphij */ 381296465Sdelphij if (8 * dgst_len > i) 382296465Sdelphij dgst_len = (i + 7) / 8; 383296465Sdelphij if (!BN_bin2bn(dgst, dgst_len, m)) { 384296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 385296465Sdelphij goto err; 386296465Sdelphij } 387296465Sdelphij /* If still too long truncate remaining bits with a shift */ 388296465Sdelphij if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) { 389296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 390296465Sdelphij goto err; 391296465Sdelphij } 392296465Sdelphij /* u1 = m * tmp mod order */ 393296465Sdelphij if (!BN_mod_mul(u1, m, u2, order, ctx)) { 394296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 395296465Sdelphij goto err; 396296465Sdelphij } 397296465Sdelphij /* u2 = r * w mod q */ 398296465Sdelphij if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) { 399296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 400296465Sdelphij goto err; 401296465Sdelphij } 402296465Sdelphij 403296465Sdelphij if ((point = EC_POINT_new(group)) == NULL) { 404296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); 405296465Sdelphij goto err; 406296465Sdelphij } 407296465Sdelphij if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) { 408296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); 409296465Sdelphij goto err; 410296465Sdelphij } 411296465Sdelphij if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == 412296465Sdelphij NID_X9_62_prime_field) { 413296465Sdelphij if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) { 414296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); 415296465Sdelphij goto err; 416296465Sdelphij } 417296465Sdelphij } else { /* NID_X9_62_characteristic_two_field */ 418296465Sdelphij 419296465Sdelphij if (!EC_POINT_get_affine_coordinates_GF2m(group, point, X, NULL, ctx)) { 420296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); 421296465Sdelphij goto err; 422296465Sdelphij } 423296465Sdelphij } 424296465Sdelphij 425296465Sdelphij if (!BN_nnmod(u1, X, order, ctx)) { 426296465Sdelphij ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); 427296465Sdelphij goto err; 428296465Sdelphij } 429296465Sdelphij /* if the signature is correct u1 is equal to sig->r */ 430296465Sdelphij ret = (BN_ucmp(u1, sig->r) == 0); 431296465Sdelphij err: 432296465Sdelphij BN_CTX_end(ctx); 433296465Sdelphij BN_CTX_free(ctx); 434296465Sdelphij if (point) 435296465Sdelphij EC_POINT_free(point); 436296465Sdelphij return ret; 437160814Ssimon} 438