/*
- * Originally written by Bodo Moeller for the OpenSSL project.
- */
-/* ====================================================================
- * Copyright (c) 1998-2003 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 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
*
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
+
/* ====================================================================
* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
* Binary polynomial ECC support in OpenSSL originally developed by
}
ret->meth = meth;
- ret->order = BN_new();
- if (ret->order == NULL)
- goto err;
- ret->cofactor = BN_new();
- if (ret->cofactor == NULL)
- goto err;
+ if ((ret->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
+ ret->order = BN_new();
+ if (ret->order == NULL)
+ goto err;
+ ret->cofactor = BN_new();
+ if (ret->cofactor == NULL)
+ goto err;
+ }
ret->asn1_flag = OPENSSL_EC_NAMED_CURVE;
ret->asn1_form = POINT_CONVERSION_UNCOMPRESSED;
if (!meth->group_init(ret))
default:
break;
#ifdef ECP_NISTZ256_REFERENCE_IMPLEMENTATION
- case pct_nistz256:
+ case PCT_nistz256:
EC_nistz256_pre_comp_free(group->pre_comp.nistz256);
break;
#endif
#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
- case pct_nistp224:
+ case PCT_nistp224:
EC_nistp224_pre_comp_free(group->pre_comp.nistp224);
break;
- case pct_nistp256:
+ case PCT_nistp256:
EC_nistp256_pre_comp_free(group->pre_comp.nistp256);
break;
- case pct_nistp521:
+ case PCT_nistp521:
EC_nistp521_pre_comp_free(group->pre_comp.nistp521);
break;
#endif
- case pct_ec:
+ case PCT_ec:
EC_ec_pre_comp_free(group->pre_comp.ec);
break;
}
if (dest == src)
return 1;
+ dest->curve_name = src->curve_name;
+
/* Copy precomputed */
dest->pre_comp_type = src->pre_comp_type;
switch (src->pre_comp_type) {
dest->pre_comp.ec = NULL;
break;
#ifdef ECP_NISTZ256_REFERENCE_IMPLEMENTATION
- case pct_nistz256:
+ case PCT_nistz256:
dest->pre_comp.nistz256 = EC_nistz256_pre_comp_dup(src->pre_comp.nistz256);
break;
#endif
#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
- case pct_nistp224:
+ case PCT_nistp224:
dest->pre_comp.nistp224 = EC_nistp224_pre_comp_dup(src->pre_comp.nistp224);
break;
- case pct_nistp256:
+ case PCT_nistp256:
dest->pre_comp.nistp256 = EC_nistp256_pre_comp_dup(src->pre_comp.nistp256);
break;
- case pct_nistp521:
+ case PCT_nistp521:
dest->pre_comp.nistp521 = EC_nistp521_pre_comp_dup(src->pre_comp.nistp521);
break;
#endif
- case pct_ec:
+ case PCT_ec:
dest->pre_comp.ec = EC_ec_pre_comp_dup(src->pre_comp.ec);
break;
}
dest->generator = NULL;
}
- if (!BN_copy(dest->order, src->order))
- return 0;
- if (!BN_copy(dest->cofactor, src->cofactor))
- return 0;
+ if ((src->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
+ if (!BN_copy(dest->order, src->order))
+ return 0;
+ if (!BN_copy(dest->cofactor, src->cofactor))
+ return 0;
+ }
- dest->curve_name = src->curve_name;
dest->asn1_flag = src->asn1_flag;
dest->asn1_form = src->asn1_form;
return meth->field_type;
}
+/*-
+ * Try computing cofactor from the generator order (n) and field cardinality (q).
+ * This works for all curves of cryptographic interest.
+ *
+ * Hasse thm: q + 1 - 2*sqrt(q) <= n*h <= q + 1 + 2*sqrt(q)
+ * h_min = (q + 1 - 2*sqrt(q))/n
+ * h_max = (q + 1 + 2*sqrt(q))/n
+ * h_max - h_min = 4*sqrt(q)/n
+ * So if n > 4*sqrt(q) holds, there is only one possible value for h:
+ * h = \lfloor (h_min + h_max)/2 \rceil = \lfloor (q + 1)/n \rceil
+ *
+ * Otherwise, zero cofactor and return success.
+ */
+static int ec_guess_cofactor(EC_GROUP *group) {
+ int ret = 0;
+ BN_CTX *ctx = NULL;
+ BIGNUM *q = NULL;
+
+ /*-
+ * If the cofactor is too large, we cannot guess it.
+ * The RHS of below is a strict overestimate of lg(4 * sqrt(q))
+ */
+ if (BN_num_bits(group->order) <= (BN_num_bits(group->field) + 1) / 2 + 3) {
+ /* default to 0 */
+ BN_zero(group->cofactor);
+ /* return success */
+ return 1;
+ }
+
+ if ((ctx = BN_CTX_new()) == NULL)
+ return 0;
+
+ BN_CTX_start(ctx);
+ if ((q = BN_CTX_get(ctx)) == NULL)
+ goto err;
+
+ /* set q = 2**m for binary fields; q = p otherwise */
+ if (group->meth->field_type == NID_X9_62_characteristic_two_field) {
+ BN_zero(q);
+ if (!BN_set_bit(q, BN_num_bits(group->field) - 1))
+ goto err;
+ } else {
+ if (!BN_copy(q, group->field))
+ goto err;
+ }
+
+ /* compute h = \lfloor (q + 1)/n \rceil = \lfloor (q + 1 + n/2)/n \rfloor */
+ if (!BN_rshift1(group->cofactor, group->order) /* n/2 */
+ || !BN_add(group->cofactor, group->cofactor, q) /* q + n/2 */
+ /* q + 1 + n/2 */
+ || !BN_add(group->cofactor, group->cofactor, BN_value_one())
+ /* (q + 1 + n/2)/n */
+ || !BN_div(group->cofactor, NULL, group->cofactor, group->order, ctx))
+ goto err;
+ ret = 1;
+ err:
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ret;
+}
+
int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
const BIGNUM *order, const BIGNUM *cofactor)
{
return 0;
}
+ /* require group->field >= 1 */
+ if (group->field == NULL || BN_is_zero(group->field)
+ || BN_is_negative(group->field)) {
+ ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_INVALID_FIELD);
+ return 0;
+ }
+
+ /*-
+ * - require order >= 1
+ * - enforce upper bound due to Hasse thm: order can be no more than one bit
+ * longer than field cardinality
+ */
+ if (order == NULL || BN_is_zero(order) || BN_is_negative(order)
+ || BN_num_bits(order) > BN_num_bits(group->field) + 1) {
+ ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_INVALID_GROUP_ORDER);
+ return 0;
+ }
+
+ /*-
+ * Unfortunately the cofactor is an optional field in many standards.
+ * Internally, the lib uses 0 cofactor as a marker for "unknown cofactor".
+ * So accept cofactor == NULL or cofactor >= 0.
+ */
+ if (cofactor != NULL && BN_is_negative(cofactor)) {
+ ECerr(EC_F_EC_GROUP_SET_GENERATOR, EC_R_UNKNOWN_COFACTOR);
+ return 0;
+ }
+
if (group->generator == NULL) {
group->generator = EC_POINT_new(group);
if (group->generator == NULL)
if (!EC_POINT_copy(group->generator, generator))
return 0;
- if (order != NULL) {
- if (!BN_copy(group->order, order))
- return 0;
- } else
- BN_zero(group->order);
+ if (!BN_copy(group->order, order))
+ return 0;
- if (cofactor != NULL) {
+ /* Either take the provided positive cofactor, or try to compute it */
+ if (cofactor != NULL && !BN_is_zero(cofactor)) {
if (!BN_copy(group->cofactor, cofactor))
return 0;
- } else
+ } else if (!ec_guess_cofactor(group)) {
BN_zero(group->cofactor);
+ return 0;
+ }
-
/*
* Some groups have an order with
* factors of two, which makes the Montgomery setup fail.
int EC_GROUP_order_bits(const EC_GROUP *group)
{
- if (group->order)
- return BN_num_bits(group->order);
- return 0;
+ OPENSSL_assert(group->meth->group_order_bits != NULL);
+ return group->meth->group_order_bits(group);
}
int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
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;
if (ctx == NULL)
ctx_new = ctx = BN_CTX_new();
}
ret->meth = group->meth;
+ ret->curve_name = group->curve_name;
if (!ret->meth->point_init(ret)) {
OPENSSL_free(ret);
ECerr(EC_F_EC_POINT_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (dest->meth != src->meth) {
+ 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;
}
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GFP,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
- return group->meth->point_set_affine_coordinates(group, point, x, y, ctx);
+ 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_GFP,
+ EC_R_POINT_IS_NOT_ON_CURVE);
+ return 0;
+ }
+ return 1;
}
#ifndef OPENSSL_NO_EC2M
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GF2M,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
- return group->meth->point_set_affine_coordinates(group, point, x, y, ctx);
+ 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_GF2M,
+ EC_R_POINT_IS_NOT_ON_CURVE);
+ return 0;
+ }
+ return 1;
}
#endif
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GFP,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
+ if (EC_POINT_is_at_infinity(group, point)) {
+ ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GFP,
+ EC_R_POINT_AT_INFINITY);
+ return 0;
+ }
return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
}
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GF2M,
EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
+ if (EC_POINT_is_at_infinity(group, point)) {
+ ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GF2M,
+ EC_R_POINT_AT_INFINITY);
+ return 0;
+ }
return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
}
#endif
ECerr(EC_F_EC_POINT_ADD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if ((group->meth != r->meth) || (r->meth != a->meth)
- || (a->meth != b->meth)) {
+ 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;
}
ECerr(EC_F_EC_POINT_DBL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if ((group->meth != r->meth) || (r->meth != a->meth)) {
+ 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;
}
ECerr(EC_F_EC_POINT_INVERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != a->meth) {
+ if (!ec_point_is_compat(a, group)) {
ECerr(EC_F_EC_POINT_INVERT, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_IS_AT_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
ECerr(EC_F_EC_POINT_IS_ON_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_IS_ON_CURVE, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
ECerr(EC_F_EC_POINT_CMP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return -1;
}
- if ((group->meth != a->meth) || (a->meth != b->meth)) {
+ 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;
}
ECerr(EC_F_EC_POINT_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
- if (group->meth != point->meth) {
+ if (!ec_point_is_compat(point, group)) {
ECerr(EC_F_EC_POINT_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
return 0;
}
for (i = 0; i < num; i++) {
- if (group->meth != points[i]->meth) {
+ if (!ec_point_is_compat(points[i], group)) {
ECerr(EC_F_EC_POINTS_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
{
return CRYPTO_get_ex_data(&key->ex_data, idx);
}
+
+int ec_group_simple_order_bits(const EC_GROUP *group)
+{
+ if (group->order == NULL)
+ return 0;
+ return BN_num_bits(group->order);
+}
+
+/*-
+ * 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);
+}