mirror of
https://github.com/openssl/openssl.git
synced 2024-12-27 06:21:43 +08:00
07caec83b8
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/11527)
1270 lines
34 KiB
C
1270 lines
34 KiB
C
/*
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* Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
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* Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
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*
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* Licensed under the Apache License 2.0 (the "License"). You may not use
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* this file except in compliance with the License. You can obtain a copy
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* in the file LICENSE in the source distribution or at
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* https://www.openssl.org/source/license.html
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*/
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/*
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* ECDSA low level APIs are deprecated for public use, but still ok for
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* internal use.
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*/
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#include "internal/deprecated.h"
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#include <string.h>
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#include <openssl/err.h>
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#include <openssl/opensslv.h>
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#include "ec_local.h"
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/* functions for EC_GROUP objects */
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EC_GROUP *EC_GROUP_new_ex(OPENSSL_CTX *libctx, const EC_METHOD *meth)
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{
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EC_GROUP *ret;
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if (meth == NULL) {
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ECerr(EC_F_EC_GROUP_NEW_EX, EC_R_SLOT_FULL);
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return NULL;
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}
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if (meth->group_init == 0) {
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ECerr(EC_F_EC_GROUP_NEW_EX, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
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return NULL;
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}
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ret = OPENSSL_zalloc(sizeof(*ret));
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if (ret == NULL) {
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ECerr(EC_F_EC_GROUP_NEW_EX, ERR_R_MALLOC_FAILURE);
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return NULL;
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}
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ret->libctx = libctx;
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ret->meth = meth;
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if ((ret->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
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ret->order = BN_new();
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if (ret->order == NULL)
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goto err;
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ret->cofactor = BN_new();
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if (ret->cofactor == NULL)
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goto err;
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}
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ret->asn1_flag = OPENSSL_EC_NAMED_CURVE;
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ret->asn1_form = POINT_CONVERSION_UNCOMPRESSED;
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if (!meth->group_init(ret))
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goto err;
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return ret;
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err:
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BN_free(ret->order);
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BN_free(ret->cofactor);
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OPENSSL_free(ret);
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return NULL;
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}
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#ifndef FIPS_MODE
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EC_GROUP *EC_GROUP_new(const EC_METHOD *meth)
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{
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return EC_GROUP_new_ex(NULL, meth);
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}
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#endif
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void EC_pre_comp_free(EC_GROUP *group)
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{
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switch (group->pre_comp_type) {
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case PCT_none:
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break;
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case PCT_nistz256:
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#ifdef ECP_NISTZ256_ASM
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EC_nistz256_pre_comp_free(group->pre_comp.nistz256);
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#endif
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break;
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#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
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case PCT_nistp224:
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EC_nistp224_pre_comp_free(group->pre_comp.nistp224);
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break;
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case PCT_nistp256:
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EC_nistp256_pre_comp_free(group->pre_comp.nistp256);
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break;
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case PCT_nistp521:
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EC_nistp521_pre_comp_free(group->pre_comp.nistp521);
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break;
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#else
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case PCT_nistp224:
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case PCT_nistp256:
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case PCT_nistp521:
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break;
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#endif
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case PCT_ec:
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EC_ec_pre_comp_free(group->pre_comp.ec);
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break;
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}
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group->pre_comp.ec = NULL;
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}
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void EC_GROUP_free(EC_GROUP *group)
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{
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if (!group)
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return;
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if (group->meth->group_finish != 0)
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group->meth->group_finish(group);
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EC_pre_comp_free(group);
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BN_MONT_CTX_free(group->mont_data);
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EC_POINT_free(group->generator);
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BN_free(group->order);
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BN_free(group->cofactor);
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OPENSSL_free(group->seed);
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OPENSSL_free(group);
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}
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#ifndef OPENSSL_NO_DEPRECATED_3_0
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void EC_GROUP_clear_free(EC_GROUP *group)
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{
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if (!group)
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return;
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if (group->meth->group_clear_finish != 0)
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group->meth->group_clear_finish(group);
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else if (group->meth->group_finish != 0)
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group->meth->group_finish(group);
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EC_pre_comp_free(group);
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BN_MONT_CTX_free(group->mont_data);
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EC_POINT_clear_free(group->generator);
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BN_clear_free(group->order);
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BN_clear_free(group->cofactor);
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OPENSSL_clear_free(group->seed, group->seed_len);
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OPENSSL_clear_free(group, sizeof(*group));
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}
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#endif
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int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
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{
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if (dest->meth->group_copy == 0) {
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ECerr(EC_F_EC_GROUP_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
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return 0;
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}
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if (dest->meth != src->meth) {
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ECerr(EC_F_EC_GROUP_COPY, EC_R_INCOMPATIBLE_OBJECTS);
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return 0;
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}
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if (dest == src)
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return 1;
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dest->libctx = src->libctx;
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dest->curve_name = src->curve_name;
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/* Copy precomputed */
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dest->pre_comp_type = src->pre_comp_type;
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switch (src->pre_comp_type) {
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case PCT_none:
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dest->pre_comp.ec = NULL;
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break;
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case PCT_nistz256:
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#ifdef ECP_NISTZ256_ASM
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dest->pre_comp.nistz256 = EC_nistz256_pre_comp_dup(src->pre_comp.nistz256);
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#endif
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break;
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#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
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case PCT_nistp224:
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dest->pre_comp.nistp224 = EC_nistp224_pre_comp_dup(src->pre_comp.nistp224);
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break;
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case PCT_nistp256:
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dest->pre_comp.nistp256 = EC_nistp256_pre_comp_dup(src->pre_comp.nistp256);
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break;
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case PCT_nistp521:
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dest->pre_comp.nistp521 = EC_nistp521_pre_comp_dup(src->pre_comp.nistp521);
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break;
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#else
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case PCT_nistp224:
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case PCT_nistp256:
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case PCT_nistp521:
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break;
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#endif
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case PCT_ec:
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dest->pre_comp.ec = EC_ec_pre_comp_dup(src->pre_comp.ec);
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break;
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}
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if (src->mont_data != NULL) {
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if (dest->mont_data == NULL) {
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dest->mont_data = BN_MONT_CTX_new();
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if (dest->mont_data == NULL)
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return 0;
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}
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if (!BN_MONT_CTX_copy(dest->mont_data, src->mont_data))
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return 0;
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} else {
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/* src->generator == NULL */
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BN_MONT_CTX_free(dest->mont_data);
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dest->mont_data = NULL;
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}
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if (src->generator != NULL) {
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if (dest->generator == NULL) {
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dest->generator = EC_POINT_new(dest);
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if (dest->generator == NULL)
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return 0;
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}
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if (!EC_POINT_copy(dest->generator, src->generator))
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return 0;
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} else {
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/* src->generator == NULL */
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EC_POINT_clear_free(dest->generator);
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dest->generator = NULL;
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}
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if ((src->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
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if (!BN_copy(dest->order, src->order))
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return 0;
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if (!BN_copy(dest->cofactor, src->cofactor))
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return 0;
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}
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dest->asn1_flag = src->asn1_flag;
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dest->asn1_form = src->asn1_form;
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if (src->seed) {
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OPENSSL_free(dest->seed);
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if ((dest->seed = OPENSSL_malloc(src->seed_len)) == NULL) {
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ECerr(EC_F_EC_GROUP_COPY, ERR_R_MALLOC_FAILURE);
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return 0;
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}
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if (!memcpy(dest->seed, src->seed, src->seed_len))
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return 0;
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dest->seed_len = src->seed_len;
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} else {
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OPENSSL_free(dest->seed);
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dest->seed = NULL;
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dest->seed_len = 0;
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}
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return dest->meth->group_copy(dest, src);
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}
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EC_GROUP *EC_GROUP_dup(const EC_GROUP *a)
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{
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EC_GROUP *t = NULL;
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int ok = 0;
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if (a == NULL)
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return NULL;
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if ((t = EC_GROUP_new_ex(a->libctx, a->meth)) == NULL)
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return NULL;
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if (!EC_GROUP_copy(t, a))
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goto err;
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ok = 1;
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err:
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if (!ok) {
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EC_GROUP_free(t);
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return NULL;
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}
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return t;
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}
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const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group)
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{
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return group->meth;
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}
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int EC_METHOD_get_field_type(const EC_METHOD *meth)
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{
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return meth->field_type;
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}
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static int ec_precompute_mont_data(EC_GROUP *);
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/*-
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* Try computing cofactor from the generator order (n) and field cardinality (q).
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* This works for all curves of cryptographic interest.
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*
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* Hasse thm: q + 1 - 2*sqrt(q) <= n*h <= q + 1 + 2*sqrt(q)
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* h_min = (q + 1 - 2*sqrt(q))/n
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* h_max = (q + 1 + 2*sqrt(q))/n
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* h_max - h_min = 4*sqrt(q)/n
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* So if n > 4*sqrt(q) holds, there is only one possible value for h:
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* h = \lfloor (h_min + h_max)/2 \rceil = \lfloor (q + 1)/n \rceil
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*
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* Otherwise, zero cofactor and return success.
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*/
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static int ec_guess_cofactor(EC_GROUP *group) {
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int ret = 0;
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BN_CTX *ctx = NULL;
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BIGNUM *q = NULL;
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/*-
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* If the cofactor is too large, we cannot guess it.
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* The RHS of below is a strict overestimate of lg(4 * sqrt(q))
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*/
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if (BN_num_bits(group->order) <= (BN_num_bits(group->field) + 1) / 2 + 3) {
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/* default to 0 */
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BN_zero(group->cofactor);
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/* return success */
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return 1;
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}
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if ((ctx = BN_CTX_new_ex(group->libctx)) == NULL)
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return 0;
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BN_CTX_start(ctx);
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if ((q = BN_CTX_get(ctx)) == NULL)
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goto err;
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/* set q = 2**m for binary fields; q = p otherwise */
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if (group->meth->field_type == NID_X9_62_characteristic_two_field) {
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BN_zero(q);
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if (!BN_set_bit(q, BN_num_bits(group->field) - 1))
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goto err;
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} else {
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if (!BN_copy(q, group->field))
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goto err;
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}
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/* compute h = \lfloor (q + 1)/n \rceil = \lfloor (q + 1 + n/2)/n \rfloor */
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if (!BN_rshift1(group->cofactor, group->order) /* n/2 */
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|| !BN_add(group->cofactor, group->cofactor, q) /* q + n/2 */
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/* q + 1 + n/2 */
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|| !BN_add(group->cofactor, group->cofactor, BN_value_one())
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/* (q + 1 + n/2)/n */
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|| !BN_div(group->cofactor, NULL, group->cofactor, group->order, ctx))
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goto err;
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ret = 1;
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err:
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BN_CTX_end(ctx);
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BN_CTX_free(ctx);
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return ret;
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}
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int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
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const BIGNUM *order, const BIGNUM *cofactor)
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{
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if (generator == NULL) {
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ECerr(EC_F_EC_GROUP_SET_GENERATOR, ERR_R_PASSED_NULL_PARAMETER);
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return 0;
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}
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/* require group->field >= 1 */
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if (group->field == NULL || BN_is_zero(group->field)
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|| BN_is_negative(group->field)) {
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ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_INVALID_FIELD);
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return 0;
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}
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/*-
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* - require order >= 1
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* - enforce upper bound due to Hasse thm: order can be no more than one bit
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* longer than field cardinality
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*/
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if (order == NULL || BN_is_zero(order) || BN_is_negative(order)
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|| BN_num_bits(order) > BN_num_bits(group->field) + 1) {
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ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_INVALID_GROUP_ORDER);
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return 0;
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}
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/*-
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* Unfortunately the cofactor is an optional field in many standards.
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* Internally, the lib uses 0 cofactor as a marker for "unknown cofactor".
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* So accept cofactor == NULL or cofactor >= 0.
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*/
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if (cofactor != NULL && BN_is_negative(cofactor)) {
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ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_UNKNOWN_COFACTOR);
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return 0;
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}
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if (group->generator == NULL) {
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group->generator = EC_POINT_new(group);
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if (group->generator == NULL)
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return 0;
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}
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if (!EC_POINT_copy(group->generator, generator))
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return 0;
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if (!BN_copy(group->order, order))
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return 0;
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/* Either take the provided positive cofactor, or try to compute it */
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if (cofactor != NULL && !BN_is_zero(cofactor)) {
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if (!BN_copy(group->cofactor, cofactor))
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return 0;
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} else if (!ec_guess_cofactor(group)) {
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BN_zero(group->cofactor);
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return 0;
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}
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/*
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* Some groups have an order with
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* factors of two, which makes the Montgomery setup fail.
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* |group->mont_data| will be NULL in this case.
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*/
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if (BN_is_odd(group->order)) {
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return ec_precompute_mont_data(group);
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}
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BN_MONT_CTX_free(group->mont_data);
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group->mont_data = NULL;
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return 1;
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}
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const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group)
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{
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return group->generator;
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}
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BN_MONT_CTX *EC_GROUP_get_mont_data(const EC_GROUP *group)
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{
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return group->mont_data;
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}
|
|
|
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int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx)
|
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{
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if (group->order == NULL)
|
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return 0;
|
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if (!BN_copy(order, group->order))
|
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return 0;
|
|
|
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return !BN_is_zero(order);
|
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}
|
|
|
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const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group)
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{
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return group->order;
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}
|
|
|
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int EC_GROUP_order_bits(const EC_GROUP *group)
|
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{
|
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return group->meth->group_order_bits(group);
|
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}
|
|
|
|
int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
|
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BN_CTX *ctx)
|
|
{
|
|
|
|
if (group->cofactor == NULL)
|
|
return 0;
|
|
if (!BN_copy(cofactor, group->cofactor))
|
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return 0;
|
|
|
|
return !BN_is_zero(group->cofactor);
|
|
}
|
|
|
|
const BIGNUM *EC_GROUP_get0_cofactor(const EC_GROUP *group)
|
|
{
|
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return group->cofactor;
|
|
}
|
|
|
|
void EC_GROUP_set_curve_name(EC_GROUP *group, int nid)
|
|
{
|
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group->curve_name = nid;
|
|
}
|
|
|
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int EC_GROUP_get_curve_name(const EC_GROUP *group)
|
|
{
|
|
return group->curve_name;
|
|
}
|
|
|
|
const BIGNUM *EC_GROUP_get0_field(const EC_GROUP *group)
|
|
{
|
|
return group->field;
|
|
}
|
|
|
|
void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag)
|
|
{
|
|
group->asn1_flag = flag;
|
|
}
|
|
|
|
int EC_GROUP_get_asn1_flag(const EC_GROUP *group)
|
|
{
|
|
return group->asn1_flag;
|
|
}
|
|
|
|
void EC_GROUP_set_point_conversion_form(EC_GROUP *group,
|
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point_conversion_form_t form)
|
|
{
|
|
group->asn1_form = form;
|
|
}
|
|
|
|
point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP
|
|
*group)
|
|
{
|
|
return group->asn1_form;
|
|
}
|
|
|
|
size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *p, size_t len)
|
|
{
|
|
OPENSSL_free(group->seed);
|
|
group->seed = NULL;
|
|
group->seed_len = 0;
|
|
|
|
if (!len || !p)
|
|
return 1;
|
|
|
|
if ((group->seed = OPENSSL_malloc(len)) == NULL) {
|
|
ECerr(EC_F_EC_GROUP_SET_SEED, ERR_R_MALLOC_FAILURE);
|
|
return 0;
|
|
}
|
|
memcpy(group->seed, p, len);
|
|
group->seed_len = len;
|
|
|
|
return len;
|
|
}
|
|
|
|
unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group)
|
|
{
|
|
return group->seed;
|
|
}
|
|
|
|
size_t EC_GROUP_get_seed_len(const EC_GROUP *group)
|
|
{
|
|
return group->seed_len;
|
|
}
|
|
|
|
int EC_GROUP_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
|
|
const BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->group_set_curve == 0) {
|
|
ECerr(EC_F_EC_GROUP_SET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
return group->meth->group_set_curve(group, p, a, b, ctx);
|
|
}
|
|
|
|
int EC_GROUP_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->group_get_curve == NULL) {
|
|
ECerr(EC_F_EC_GROUP_GET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
return group->meth->group_get_curve(group, p, a, b, ctx);
|
|
}
|
|
|
|
#ifndef OPENSSL_NO_DEPRECATED_3_0
|
|
int EC_GROUP_set_curve_GFp(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
|
|
const BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return EC_GROUP_set_curve(group, p, a, b, ctx);
|
|
}
|
|
|
|
int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
|
|
BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return EC_GROUP_get_curve(group, p, a, b, ctx);
|
|
}
|
|
|
|
# ifndef OPENSSL_NO_EC2M
|
|
int EC_GROUP_set_curve_GF2m(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
|
|
const BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return EC_GROUP_set_curve(group, p, a, b, ctx);
|
|
}
|
|
|
|
int EC_GROUP_get_curve_GF2m(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
|
|
BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return EC_GROUP_get_curve(group, p, a, b, ctx);
|
|
}
|
|
# endif
|
|
#endif
|
|
|
|
int EC_GROUP_get_degree(const EC_GROUP *group)
|
|
{
|
|
if (group->meth->group_get_degree == 0) {
|
|
ECerr(EC_F_EC_GROUP_GET_DEGREE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
return group->meth->group_get_degree(group);
|
|
}
|
|
|
|
int EC_GROUP_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->group_check_discriminant == 0) {
|
|
ECerr(EC_F_EC_GROUP_CHECK_DISCRIMINANT,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
return group->meth->group_check_discriminant(group, ctx);
|
|
}
|
|
|
|
int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
|
|
{
|
|
int r = 0;
|
|
BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
|
|
#ifndef FIPS_MODE
|
|
BN_CTX *ctx_new = NULL;
|
|
#endif
|
|
|
|
/* compare the field types */
|
|
if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
|
|
EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
|
|
return 1;
|
|
/* compare the curve name (if present in both) */
|
|
if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
|
|
EC_GROUP_get_curve_name(a) != EC_GROUP_get_curve_name(b))
|
|
return 1;
|
|
if (a->meth->flags & EC_FLAGS_CUSTOM_CURVE)
|
|
return 0;
|
|
|
|
#ifndef FIPS_MODE
|
|
if (ctx == NULL)
|
|
ctx_new = ctx = BN_CTX_new();
|
|
#endif
|
|
if (ctx == NULL)
|
|
return -1;
|
|
|
|
BN_CTX_start(ctx);
|
|
a1 = BN_CTX_get(ctx);
|
|
a2 = BN_CTX_get(ctx);
|
|
a3 = BN_CTX_get(ctx);
|
|
b1 = BN_CTX_get(ctx);
|
|
b2 = BN_CTX_get(ctx);
|
|
b3 = BN_CTX_get(ctx);
|
|
if (b3 == NULL) {
|
|
BN_CTX_end(ctx);
|
|
#ifndef FIPS_MODE
|
|
BN_CTX_free(ctx_new);
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* XXX This approach assumes that the external representation of curves
|
|
* over the same field type is the same.
|
|
*/
|
|
if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
|
|
!b->meth->group_get_curve(b, b1, b2, b3, ctx))
|
|
r = 1;
|
|
|
|
/* return 1 if the curve parameters are different */
|
|
if (r || BN_cmp(a1, b1) != 0 || BN_cmp(a2, b2) != 0 || BN_cmp(a3, b3) != 0)
|
|
r = 1;
|
|
|
|
/* XXX EC_POINT_cmp() assumes that the methods are equal */
|
|
/* return 1 if the generators are different */
|
|
if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
|
|
EC_GROUP_get0_generator(b), ctx) != 0)
|
|
r = 1;
|
|
|
|
if (!r) {
|
|
const BIGNUM *ao, *bo, *ac, *bc;
|
|
/* compare the orders */
|
|
ao = EC_GROUP_get0_order(a);
|
|
bo = EC_GROUP_get0_order(b);
|
|
if (ao == NULL || bo == NULL) {
|
|
/* return an error if either order is NULL */
|
|
r = -1;
|
|
goto end;
|
|
}
|
|
if (BN_cmp(ao, bo) != 0) {
|
|
/* return 1 if orders are different */
|
|
r = 1;
|
|
goto end;
|
|
}
|
|
/*
|
|
* It gets here if the curve parameters and generator matched.
|
|
* Now check the optional cofactors (if both are present).
|
|
*/
|
|
ac = EC_GROUP_get0_cofactor(a);
|
|
bc = EC_GROUP_get0_cofactor(b);
|
|
/* Returns 1 (mismatch) if both cofactors are specified and different */
|
|
if (!BN_is_zero(ac) && !BN_is_zero(bc) && BN_cmp(ac, bc) != 0)
|
|
r = 1;
|
|
/* Returns 0 if the parameters matched */
|
|
}
|
|
end:
|
|
BN_CTX_end(ctx);
|
|
#ifndef FIPS_MODE
|
|
BN_CTX_free(ctx_new);
|
|
#endif
|
|
return r;
|
|
}
|
|
|
|
/* functions for EC_POINT objects */
|
|
|
|
EC_POINT *EC_POINT_new(const EC_GROUP *group)
|
|
{
|
|
EC_POINT *ret;
|
|
|
|
if (group == NULL) {
|
|
ECerr(EC_F_EC_POINT_NEW, ERR_R_PASSED_NULL_PARAMETER);
|
|
return NULL;
|
|
}
|
|
if (group->meth->point_init == NULL) {
|
|
ECerr(EC_F_EC_POINT_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return NULL;
|
|
}
|
|
|
|
ret = OPENSSL_zalloc(sizeof(*ret));
|
|
if (ret == NULL) {
|
|
ECerr(EC_F_EC_POINT_NEW, ERR_R_MALLOC_FAILURE);
|
|
return NULL;
|
|
}
|
|
|
|
ret->meth = group->meth;
|
|
ret->curve_name = group->curve_name;
|
|
|
|
if (!ret->meth->point_init(ret)) {
|
|
OPENSSL_free(ret);
|
|
return NULL;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void EC_POINT_free(EC_POINT *point)
|
|
{
|
|
if (point == NULL)
|
|
return;
|
|
|
|
if (point->meth->point_finish != 0)
|
|
point->meth->point_finish(point);
|
|
OPENSSL_free(point);
|
|
}
|
|
|
|
void EC_POINT_clear_free(EC_POINT *point)
|
|
{
|
|
if (point == NULL)
|
|
return;
|
|
|
|
if (point->meth->point_clear_finish != 0)
|
|
point->meth->point_clear_finish(point);
|
|
else if (point->meth->point_finish != 0)
|
|
point->meth->point_finish(point);
|
|
OPENSSL_clear_free(point, sizeof(*point));
|
|
}
|
|
|
|
int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src)
|
|
{
|
|
if (dest->meth->point_copy == 0) {
|
|
ECerr(EC_F_EC_POINT_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (dest->meth != src->meth
|
|
|| (dest->curve_name != src->curve_name
|
|
&& dest->curve_name != 0
|
|
&& src->curve_name != 0)) {
|
|
ECerr(EC_F_EC_POINT_COPY, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
if (dest == src)
|
|
return 1;
|
|
return dest->meth->point_copy(dest, src);
|
|
}
|
|
|
|
EC_POINT *EC_POINT_dup(const EC_POINT *a, const EC_GROUP *group)
|
|
{
|
|
EC_POINT *t;
|
|
int r;
|
|
|
|
if (a == NULL)
|
|
return NULL;
|
|
|
|
t = EC_POINT_new(group);
|
|
if (t == NULL)
|
|
return NULL;
|
|
r = EC_POINT_copy(t, a);
|
|
if (!r) {
|
|
EC_POINT_free(t);
|
|
return NULL;
|
|
}
|
|
return t;
|
|
}
|
|
|
|
const EC_METHOD *EC_POINT_method_of(const EC_POINT *point)
|
|
{
|
|
return point->meth;
|
|
}
|
|
|
|
int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point)
|
|
{
|
|
if (group->meth->point_set_to_infinity == 0) {
|
|
ECerr(EC_F_EC_POINT_SET_TO_INFINITY,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (group->meth != point->meth) {
|
|
ECerr(EC_F_EC_POINT_SET_TO_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->point_set_to_infinity(group, point);
|
|
}
|
|
|
|
#ifndef OPENSSL_NO_DEPRECATED_3_0
|
|
int 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)
|
|
{
|
|
if (group->meth->field_type != NID_X9_62_prime_field) {
|
|
ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
|
|
EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return ec_GFp_simple_set_Jprojective_coordinates_GFp(group, point, x, y, z, ctx);
|
|
}
|
|
|
|
int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group,
|
|
const EC_POINT *point, BIGNUM *x,
|
|
BIGNUM *y, BIGNUM *z,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->field_type != NID_X9_62_prime_field) {
|
|
ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
|
|
EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return ec_GFp_simple_get_Jprojective_coordinates_GFp(group, point, x, y, z, ctx);
|
|
}
|
|
#endif
|
|
|
|
int EC_POINT_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point,
|
|
const BIGNUM *x, const BIGNUM *y,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->point_set_affine_coordinates == NULL) {
|
|
ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
if (!group->meth->point_set_affine_coordinates(group, point, x, y, ctx))
|
|
return 0;
|
|
|
|
if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
|
|
ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_POINT_IS_NOT_ON_CURVE);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
#ifndef OPENSSL_NO_DEPRECATED_3_0
|
|
int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group,
|
|
EC_POINT *point, const BIGNUM *x,
|
|
const BIGNUM *y, BN_CTX *ctx)
|
|
{
|
|
return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
|
|
}
|
|
|
|
# ifndef OPENSSL_NO_EC2M
|
|
int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group,
|
|
EC_POINT *point, const BIGNUM *x,
|
|
const BIGNUM *y, BN_CTX *ctx)
|
|
{
|
|
return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
|
|
}
|
|
# endif
|
|
#endif
|
|
|
|
int EC_POINT_get_affine_coordinates(const EC_GROUP *group,
|
|
const EC_POINT *point, BIGNUM *x, BIGNUM *y,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->point_get_affine_coordinates == NULL) {
|
|
ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
if (EC_POINT_is_at_infinity(group, point)) {
|
|
ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES, EC_R_POINT_AT_INFINITY);
|
|
return 0;
|
|
}
|
|
return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
|
|
}
|
|
|
|
#ifndef OPENSSL_NO_DEPRECATED_3_0
|
|
int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group,
|
|
const EC_POINT *point, BIGNUM *x,
|
|
BIGNUM *y, BN_CTX *ctx)
|
|
{
|
|
return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
|
|
}
|
|
|
|
# ifndef OPENSSL_NO_EC2M
|
|
int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group,
|
|
const EC_POINT *point, BIGNUM *x,
|
|
BIGNUM *y, BN_CTX *ctx)
|
|
{
|
|
return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
|
|
}
|
|
# endif
|
|
#endif
|
|
|
|
int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
|
|
const EC_POINT *b, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->add == 0) {
|
|
ECerr(EC_F_EC_POINT_ADD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)
|
|
|| !ec_point_is_compat(b, group)) {
|
|
ECerr(EC_F_EC_POINT_ADD, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->add(group, r, a, b, ctx);
|
|
}
|
|
|
|
int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->dbl == 0) {
|
|
ECerr(EC_F_EC_POINT_DBL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)) {
|
|
ECerr(EC_F_EC_POINT_DBL, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->dbl(group, r, a, ctx);
|
|
}
|
|
|
|
int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->invert == 0) {
|
|
ECerr(EC_F_EC_POINT_INVERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(a, group)) {
|
|
ECerr(EC_F_EC_POINT_INVERT, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->invert(group, a, ctx);
|
|
}
|
|
|
|
int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
|
|
{
|
|
if (group->meth->is_at_infinity == 0) {
|
|
ECerr(EC_F_EC_POINT_IS_AT_INFINITY,
|
|
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_IS_AT_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->is_at_infinity(group, point);
|
|
}
|
|
|
|
/*
|
|
* Check whether an EC_POINT is on the curve or not. Note that the return
|
|
* value for this function should NOT be treated as a boolean. Return values:
|
|
* 1: The point is on the curve
|
|
* 0: The point is not on the curve
|
|
* -1: An error occurred
|
|
*/
|
|
int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->is_on_curve == 0) {
|
|
ECerr(EC_F_EC_POINT_IS_ON_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_IS_ON_CURVE, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->is_on_curve(group, point, ctx);
|
|
}
|
|
|
|
int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b,
|
|
BN_CTX *ctx)
|
|
{
|
|
if (group->meth->point_cmp == 0) {
|
|
ECerr(EC_F_EC_POINT_CMP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return -1;
|
|
}
|
|
if (!ec_point_is_compat(a, group) || !ec_point_is_compat(b, group)) {
|
|
ECerr(EC_F_EC_POINT_CMP, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return -1;
|
|
}
|
|
return group->meth->point_cmp(group, a, b, ctx);
|
|
}
|
|
|
|
int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->make_affine == 0) {
|
|
ECerr(EC_F_EC_POINT_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
if (!ec_point_is_compat(point, group)) {
|
|
ECerr(EC_F_EC_POINT_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
return group->meth->make_affine(group, point, ctx);
|
|
}
|
|
|
|
int EC_POINTs_make_affine(const EC_GROUP *group, size_t num,
|
|
EC_POINT *points[], BN_CTX *ctx)
|
|
{
|
|
size_t i;
|
|
|
|
if (group->meth->points_make_affine == 0) {
|
|
ECerr(EC_F_EC_POINTS_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
|
|
return 0;
|
|
}
|
|
for (i = 0; i < num; i++) {
|
|
if (!ec_point_is_compat(points[i], group)) {
|
|
ECerr(EC_F_EC_POINTS_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
}
|
|
return group->meth->points_make_affine(group, num, points, ctx);
|
|
}
|
|
|
|
/*
|
|
* Functions for point multiplication. If group->meth->mul is 0, we use the
|
|
* wNAF-based implementations in ec_mult.c; otherwise we dispatch through
|
|
* methods.
|
|
*/
|
|
|
|
int 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)
|
|
{
|
|
int ret = 0;
|
|
size_t i = 0;
|
|
#ifndef FIPS_MODE
|
|
BN_CTX *new_ctx = NULL;
|
|
#endif
|
|
|
|
if (!ec_point_is_compat(r, group)) {
|
|
ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
|
|
if (scalar == NULL && num == 0)
|
|
return EC_POINT_set_to_infinity(group, r);
|
|
|
|
for (i = 0; i < num; i++) {
|
|
if (!ec_point_is_compat(points[i], group)) {
|
|
ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
#ifndef FIPS_MODE
|
|
if (ctx == NULL)
|
|
ctx = new_ctx = BN_CTX_secure_new();
|
|
#endif
|
|
if (ctx == NULL) {
|
|
ECerr(EC_F_EC_POINTS_MUL, ERR_R_INTERNAL_ERROR);
|
|
return 0;
|
|
}
|
|
|
|
if (group->meth->mul != NULL)
|
|
ret = group->meth->mul(group, r, scalar, num, points, scalars, ctx);
|
|
else
|
|
/* use default */
|
|
ret = ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx);
|
|
|
|
#ifndef FIPS_MODE
|
|
BN_CTX_free(new_ctx);
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
int 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)
|
|
{
|
|
/* just a convenient interface to EC_POINTs_mul() */
|
|
|
|
const EC_POINT *points[1];
|
|
const BIGNUM *scalars[1];
|
|
|
|
points[0] = point;
|
|
scalars[0] = p_scalar;
|
|
|
|
return EC_POINTs_mul(group, r, g_scalar,
|
|
(point != NULL
|
|
&& p_scalar != NULL), points, scalars, ctx);
|
|
}
|
|
|
|
int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->mul == 0)
|
|
/* use default */
|
|
return ec_wNAF_precompute_mult(group, ctx);
|
|
|
|
if (group->meth->precompute_mult != 0)
|
|
return group->meth->precompute_mult(group, ctx);
|
|
else
|
|
return 1; /* nothing to do, so report success */
|
|
}
|
|
|
|
int EC_GROUP_have_precompute_mult(const EC_GROUP *group)
|
|
{
|
|
if (group->meth->mul == 0)
|
|
/* use default */
|
|
return ec_wNAF_have_precompute_mult(group);
|
|
|
|
if (group->meth->have_precompute_mult != 0)
|
|
return group->meth->have_precompute_mult(group);
|
|
else
|
|
return 0; /* cannot tell whether precomputation has
|
|
* been performed */
|
|
}
|
|
|
|
/*
|
|
* ec_precompute_mont_data sets |group->mont_data| from |group->order| and
|
|
* returns one on success. On error it returns zero.
|
|
*/
|
|
static int ec_precompute_mont_data(EC_GROUP *group)
|
|
{
|
|
BN_CTX *ctx = BN_CTX_new_ex(group->libctx);
|
|
int ret = 0;
|
|
|
|
BN_MONT_CTX_free(group->mont_data);
|
|
group->mont_data = NULL;
|
|
|
|
if (ctx == NULL)
|
|
goto err;
|
|
|
|
group->mont_data = BN_MONT_CTX_new();
|
|
if (group->mont_data == NULL)
|
|
goto err;
|
|
|
|
if (!BN_MONT_CTX_set(group->mont_data, group->order, ctx)) {
|
|
BN_MONT_CTX_free(group->mont_data);
|
|
group->mont_data = NULL;
|
|
goto err;
|
|
}
|
|
|
|
ret = 1;
|
|
|
|
err:
|
|
|
|
BN_CTX_free(ctx);
|
|
return ret;
|
|
}
|
|
|
|
#ifndef FIPS_MODE
|
|
int EC_KEY_set_ex_data(EC_KEY *key, int idx, void *arg)
|
|
{
|
|
return CRYPTO_set_ex_data(&key->ex_data, idx, arg);
|
|
}
|
|
|
|
void *EC_KEY_get_ex_data(const EC_KEY *key, int idx)
|
|
{
|
|
return CRYPTO_get_ex_data(&key->ex_data, idx);
|
|
}
|
|
#endif
|
|
|
|
int ec_group_simple_order_bits(const EC_GROUP *group)
|
|
{
|
|
if (group->order == NULL)
|
|
return 0;
|
|
return BN_num_bits(group->order);
|
|
}
|
|
|
|
static int ec_field_inverse_mod_ord(const EC_GROUP *group, BIGNUM *r,
|
|
const BIGNUM *x, BN_CTX *ctx)
|
|
{
|
|
BIGNUM *e = NULL;
|
|
int ret = 0;
|
|
#ifndef FIPS_MODE
|
|
BN_CTX *new_ctx = NULL;
|
|
#endif
|
|
|
|
if (group->mont_data == NULL)
|
|
return 0;
|
|
|
|
#ifndef FIPS_MODE
|
|
if (ctx == NULL)
|
|
ctx = new_ctx = BN_CTX_secure_new();
|
|
#endif
|
|
if (ctx == NULL)
|
|
return 0;
|
|
|
|
BN_CTX_start(ctx);
|
|
if ((e = BN_CTX_get(ctx)) == NULL)
|
|
goto err;
|
|
|
|
/*-
|
|
* We want inverse in constant time, therefore we utilize the fact
|
|
* order must be prime and use Fermats Little Theorem instead.
|
|
*/
|
|
if (!BN_set_word(e, 2))
|
|
goto err;
|
|
if (!BN_sub(e, group->order, e))
|
|
goto err;
|
|
/*-
|
|
* Exponent e is public.
|
|
* No need for scatter-gather or BN_FLG_CONSTTIME.
|
|
*/
|
|
if (!BN_mod_exp_mont(r, x, e, group->order, ctx, group->mont_data))
|
|
goto err;
|
|
|
|
ret = 1;
|
|
|
|
err:
|
|
BN_CTX_end(ctx);
|
|
#ifndef FIPS_MODE
|
|
BN_CTX_free(new_ctx);
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
/*-
|
|
* Default behavior, if group->meth->field_inverse_mod_ord is NULL:
|
|
* - When group->order is even, this function returns an error.
|
|
* - When group->order is otherwise composite, the correctness
|
|
* of the output is not guaranteed.
|
|
* - When x is outside the range [1, group->order), the correctness
|
|
* of the output is not guaranteed.
|
|
* - Otherwise, this function returns the multiplicative inverse in the
|
|
* range [1, group->order).
|
|
*
|
|
* EC_METHODs must implement their own field_inverse_mod_ord for
|
|
* other functionality.
|
|
*/
|
|
int ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,
|
|
const BIGNUM *x, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->field_inverse_mod_ord != NULL)
|
|
return group->meth->field_inverse_mod_ord(group, res, x, ctx);
|
|
else
|
|
return ec_field_inverse_mod_ord(group, res, x, ctx);
|
|
}
|
|
|
|
/*-
|
|
* Coordinate blinding for EC_POINT.
|
|
*
|
|
* The underlying EC_METHOD can optionally implement this function:
|
|
* underlying implementations should return 0 on errors, or 1 on
|
|
* success.
|
|
*
|
|
* This wrapper returns 1 in case the underlying EC_METHOD does not
|
|
* support coordinate blinding.
|
|
*/
|
|
int ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx)
|
|
{
|
|
if (group->meth->blind_coordinates == NULL)
|
|
return 1; /* ignore if not implemented */
|
|
|
|
return group->meth->blind_coordinates(group, p, ctx);
|
|
}
|