ec_oct.c revision 1.7 
1/* $OpenBSD: ec_oct.c,v 1.7 2021/04/20 17:32:57 tb Exp $ */
2/*
3 * Originally written by Bodo Moeller for the OpenSSL project.
4 */
5/* ====================================================================
6 * Copyright (c) 1998-2003 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    openssl-core@openssl.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58/* ====================================================================
59 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60 * Binary polynomial ECC support in OpenSSL originally developed by
61 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
62 */
63
64#include <string.h>
65
66#include <openssl/opensslconf.h>
67
68#include <openssl/err.h>
69#include <openssl/opensslv.h>
70
71#include "ec_lcl.h"
72
73int
74EC_POINT_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point,
75    const BIGNUM *x, int y_bit, BN_CTX *ctx)
76{
77	if (group->meth->point_set_compressed_coordinates == 0
78	    && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
79		ECerror(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
80		return 0;
81	}
82	if (group->meth != point->meth) {
83		ECerror(EC_R_INCOMPATIBLE_OBJECTS);
84		return 0;
85	}
86	if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
87		if (group->meth->field_type == NID_X9_62_prime_field)
88			return ec_GFp_simple_set_compressed_coordinates(
89			    group, point, x, y_bit, ctx);
90		else
91#ifdef OPENSSL_NO_EC2M
92		{
93			ECerror(EC_R_GF2M_NOT_SUPPORTED);
94			return 0;
95		}
96#else
97			return ec_GF2m_simple_set_compressed_coordinates(
98			    group, point, x, y_bit, ctx);
99#endif
100	}
101	if (!group->meth->point_set_compressed_coordinates(group, point, x,
102	    y_bit, ctx))
103		return 0;
104	if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
105		ECerror(EC_R_POINT_IS_NOT_ON_CURVE);
106		return 0;
107	}
108	return 1;
109}
110
111int
112EC_POINT_set_compressed_coordinates_GFp(const EC_GROUP *group, EC_POINT *point,
113    const BIGNUM *x, int y_bit, BN_CTX *ctx)
114{
115	return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
116}
117
118#ifndef OPENSSL_NO_EC2M
119int
120EC_POINT_set_compressed_coordinates_GF2m(const EC_GROUP *group, EC_POINT *point,
121    const BIGNUM *x, int y_bit, BN_CTX *ctx)
122{
123	return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
124}
125#endif
126
127size_t
128EC_POINT_point2oct(const EC_GROUP *group, const EC_POINT *point,
129    point_conversion_form_t form,
130    unsigned char *buf, size_t len, BN_CTX *ctx)
131{
132	if (group->meth->point2oct == 0
133	    && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
134		ECerror(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
135		return 0;
136	}
137	if (group->meth != point->meth) {
138		ECerror(EC_R_INCOMPATIBLE_OBJECTS);
139		return 0;
140	}
141	if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
142		if (group->meth->field_type == NID_X9_62_prime_field)
143			return ec_GFp_simple_point2oct(group, point,
144			    form, buf, len, ctx);
145		else
146#ifdef OPENSSL_NO_EC2M
147		{
148			ECerror(EC_R_GF2M_NOT_SUPPORTED);
149			return 0;
150		}
151#else
152			return ec_GF2m_simple_point2oct(group, point,
153			    form, buf, len, ctx);
154#endif
155	}
156	return group->meth->point2oct(group, point, form, buf, len, ctx);
157}
158
159int
160EC_POINT_oct2point(const EC_GROUP *group, EC_POINT *point,
161    const unsigned char *buf, size_t len, BN_CTX *ctx)
162{
163	if (group->meth->oct2point == 0 &&
164	    !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
165		ECerror(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
166		return 0;
167	}
168	if (group->meth != point->meth) {
169		ECerror(EC_R_INCOMPATIBLE_OBJECTS);
170		return 0;
171	}
172	if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
173		if (group->meth->field_type == NID_X9_62_prime_field)
174			return ec_GFp_simple_oct2point(group, point,
175			    buf, len, ctx);
176		else
177#ifdef OPENSSL_NO_EC2M
178		{
179			ECerror(EC_R_GF2M_NOT_SUPPORTED);
180			return 0;
181		}
182#else
183			return ec_GF2m_simple_oct2point(group, point,
184			    buf, len, ctx);
185#endif
186	}
187	return group->meth->oct2point(group, point, buf, len, ctx);
188}
189