blob: 2ae33b2babd4ebf01d8a9fb848465ff613971e3d [file] [log] [blame]
/* Originally written by Bodo Moeller for the OpenSSL project.
* ====================================================================
* Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* ====================================================================
* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
*
* Portions of the attached software ("Contribution") are developed by
* SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
*
* The Contribution is licensed pursuant to the OpenSSL open source
* license provided above.
*
* The elliptic curve binary polynomial software is originally written by
* Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
* Laboratories. */
#include <openssl/ec_key.h>
#include <openssl/ec.h>
#include <openssl/engine.h>
#include <openssl/err.h>
#include <openssl/ex_data.h>
#include <openssl/mem.h>
#include "internal.h"
EC_KEY *EC_KEY_new(void) { return EC_KEY_new_method(NULL); }
EC_KEY *EC_KEY_new_method(const ENGINE *engine) {
EC_KEY *ret = (EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY));
if (ret == NULL) {
OPENSSL_PUT_ERROR(EC, EC_KEY_new_method, ERR_R_MALLOC_FAILURE);
return NULL;
}
memset(ret, 0, sizeof(EC_KEY));
if (engine) {
ret->ecdsa_meth = ENGINE_get_ECDSA_method(engine);
}
if (ret->ecdsa_meth) {
METHOD_ref(ret->ecdsa_meth);
}
ret->version = 1;
ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
ret->references = 1;
if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_EC_KEY, ret, &ret->ex_data)) {
goto err1;
}
if (ret->ecdsa_meth && ret->ecdsa_meth->init && !ret->ecdsa_meth->init(ret)) {
goto err2;
}
return ret;
err2:
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_EC_KEY, ret, &ret->ex_data);
err1:
if (ret->ecdsa_meth) {
METHOD_unref(ret->ecdsa_meth);
}
OPENSSL_free(ret);
return NULL;
}
EC_KEY *EC_KEY_new_by_curve_name(int nid) {
EC_KEY *ret = EC_KEY_new();
if (ret == NULL) {
return NULL;
}
ret->group = EC_GROUP_new_by_curve_name(nid);
if (ret->group == NULL) {
EC_KEY_free(ret);
return NULL;
}
return ret;
}
void EC_KEY_free(EC_KEY *r) {
if (r == NULL) {
return;
}
if (CRYPTO_add(&r->references, -1, CRYPTO_LOCK_EC)) {
return;
}
if (r->ecdsa_meth) {
if (r->ecdsa_meth->finish) {
r->ecdsa_meth->finish(r);
}
METHOD_unref(r->ecdsa_meth);
}
if (r->group != NULL) {
EC_GROUP_free(r->group);
}
if (r->pub_key != NULL) {
EC_POINT_free(r->pub_key);
}
if (r->priv_key != NULL) {
BN_clear_free(r->priv_key);
}
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_EC_KEY, r, &r->ex_data);
OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
OPENSSL_free(r);
}
EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) {
if (dest == NULL || src == NULL) {
OPENSSL_PUT_ERROR(EC, EC_KEY_copy, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
/* copy the parameters */
if (src->group) {
/* TODO(fork): duplicating the group seems wasteful. */
const EC_METHOD *meth = src->group->meth;
/* clear the old group */
if (dest->group) {
EC_GROUP_free(dest->group);
}
dest->group = ec_group_new(meth);
if (dest->group == NULL) {
return NULL;
}
if (!EC_GROUP_copy(dest->group, src->group)) {
return NULL;
}
}
/* copy the public key */
if (src->pub_key && src->group) {
if (dest->pub_key) {
EC_POINT_free(dest->pub_key);
}
dest->pub_key = EC_POINT_new(src->group);
if (dest->pub_key == NULL) {
return NULL;
}
if (!EC_POINT_copy(dest->pub_key, src->pub_key)) {
return NULL;
}
}
/* copy the private key */
if (src->priv_key) {
if (dest->priv_key == NULL) {
dest->priv_key = BN_new();
if (dest->priv_key == NULL) {
return NULL;
}
}
if (!BN_copy(dest->priv_key, src->priv_key)) {
return NULL;
}
}
/* copy method/extra data */
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_EC_KEY, dest, &dest->ex_data);
if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_EC_KEY, &dest->ex_data,
&src->ex_data)) {
return NULL;
}
/* copy the rest */
dest->enc_flag = src->enc_flag;
dest->conv_form = src->conv_form;
dest->version = src->version;
dest->flags = src->flags;
return dest;
}
EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) {
EC_KEY *ret = EC_KEY_new();
if (ret == NULL) {
return NULL;
}
if (EC_KEY_copy(ret, ec_key) == NULL) {
EC_KEY_free(ret);
return NULL;
}
return ret;
}
int EC_KEY_up_ref(EC_KEY *r) {
return CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC) > 1;
}
int EC_KEY_is_opaque(const EC_KEY *key) {
return key->ecdsa_meth && (key->ecdsa_meth->flags & ECDSA_FLAG_OPAQUE);
}
const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; }
int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) {
if (key->group != NULL) {
EC_GROUP_free(key->group);
}
/* TODO(fork): duplicating the group seems wasteful but see
* |EC_KEY_set_conv_form|. */
key->group = EC_GROUP_dup(group);
return (key->group == NULL) ? 0 : 1;
}
const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) {
return key->priv_key;
}
int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) {
if (key->priv_key) {
BN_clear_free(key->priv_key);
}
key->priv_key = BN_dup(priv_key);
return (key->priv_key == NULL) ? 0 : 1;
}
const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) {
return key->pub_key;
}
int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) {
if (key->pub_key != NULL) {
EC_POINT_free(key->pub_key);
}
key->pub_key = EC_POINT_dup(pub_key, key->group);
return (key->pub_key == NULL) ? 0 : 1;
}
unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) { return key->enc_flag; }
void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) {
key->enc_flag = flags;
}
point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) {
return key->conv_form;
}
void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) {
key->conv_form = cform;
if (key->group != NULL) {
EC_GROUP_set_point_conversion_form(key->group, cform);
}
}
int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) {
if (key->group == NULL) {
return 0;
}
return EC_GROUP_precompute_mult(key->group, ctx);
}
int EC_KEY_check_key(const EC_KEY *eckey) {
int ok = 0;
BN_CTX *ctx = NULL;
const BIGNUM *order = NULL;
EC_POINT *point = NULL;
if (!eckey || !eckey->group || !eckey->pub_key) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_POINT_AT_INFINITY);
goto err;
}
ctx = BN_CTX_new();
point = EC_POINT_new(eckey->group);
if (ctx == NULL ||
point == NULL) {
goto err;
}
/* testing whether the pub_key is on the elliptic curve */
if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
/* testing whether pub_key * order is the point at infinity */
/* TODO(fork): can this be skipped if the cofactor is one or if we're about
* to check the private key, below? */
order = &eckey->group->order;
if (BN_is_zero(order)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_INVALID_GROUP_ORDER);
goto err;
}
if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, ERR_R_EC_LIB);
goto err;
}
if (!EC_POINT_is_at_infinity(eckey->group, point)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_WRONG_ORDER);
goto err;
}
/* in case the priv_key is present :
* check if generator * priv_key == pub_key
*/
if (eckey->priv_key) {
if (BN_cmp(eckey->priv_key, order) >= 0) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_WRONG_ORDER);
goto err;
}
if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, ERR_R_EC_LIB);
goto err;
}
if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {
OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_INVALID_PRIVATE_KEY);
goto err;
}
}
ok = 1;
err:
if (ctx != NULL)
BN_CTX_free(ctx);
if (point != NULL)
EC_POINT_free(point);
return ok;
}
int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,
BIGNUM *y) {
BN_CTX *ctx = NULL;
BIGNUM *tx, *ty;
EC_POINT *point = NULL;
int ok = 0;
if (!key || !key->group || !x || !y) {
OPENSSL_PUT_ERROR(EC, EC_KEY_set_public_key_affine_coordinates,
ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
ctx = BN_CTX_new();
point = EC_POINT_new(key->group);
if (ctx == NULL ||
point == NULL) {
goto err;
}
tx = BN_CTX_get(ctx);
ty = BN_CTX_get(ctx);
if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
!EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {
goto err;
}
/* Check if retrieved coordinates match originals: if not values
* are out of range. */
if (BN_cmp(x, tx) || BN_cmp(y, ty)) {
OPENSSL_PUT_ERROR(EC, EC_KEY_set_public_key_affine_coordinates,
EC_R_COORDINATES_OUT_OF_RANGE);
goto err;
}
if (!EC_KEY_set_public_key(key, point)) {
goto err;
}
if (EC_KEY_check_key(key) == 0) {
goto err;
}
ok = 1;
err:
if (ctx)
BN_CTX_free(ctx);
if (point)
EC_POINT_free(point);
return ok;
}
int EC_KEY_generate_key(EC_KEY *eckey) {
int ok = 0;
BN_CTX *ctx = NULL;
BIGNUM *priv_key = NULL, *order = NULL;
EC_POINT *pub_key = NULL;
if (!eckey || !eckey->group) {
OPENSSL_PUT_ERROR(EC, EC_KEY_generate_key, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
order = BN_new();
ctx = BN_CTX_new();
if (order == NULL ||
ctx == NULL) {
goto err;
}
if (eckey->priv_key == NULL) {
priv_key = BN_new();
if (priv_key == NULL) {
goto err;
}
} else {
priv_key = eckey->priv_key;
}
if (!EC_GROUP_get_order(eckey->group, order, ctx)) {
goto err;
}
do {
if (!BN_rand_range(priv_key, order)) {
goto err;
}
} while (BN_is_zero(priv_key));
if (eckey->pub_key == NULL) {
pub_key = EC_POINT_new(eckey->group);
if (pub_key == NULL) {
goto err;
}
} else {
pub_key = eckey->pub_key;
}
if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) {
goto err;
}
eckey->priv_key = priv_key;
eckey->pub_key = pub_key;
ok = 1;
err:
if (order)
BN_free(order);
if (pub_key != NULL && eckey->pub_key == NULL)
EC_POINT_free(pub_key);
if (priv_key != NULL && eckey->priv_key == NULL)
BN_free(priv_key);
if (ctx != NULL)
BN_CTX_free(ctx);
return ok;
}
int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
CRYPTO_EX_dup *dup_func,
CRYPTO_EX_free *free_func) {
return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_EC_KEY, argl, argp, new_func,
dup_func, free_func);
}
int EC_KEY_set_ex_data(EC_KEY *d, int idx, void *arg) {
return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
}
void *EC_KEY_get_ex_data(const EC_KEY *d, int idx) {
return CRYPTO_get_ex_data(&d->ex_data, idx);
}