GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcrypto/ec/ec_cvt.c Lines: 12 31 38.7 %
Date: 2017-11-13 Branches: 4 20 20.0 %

Line Branch Exec Source
1
/* $OpenBSD: ec_cvt.c,v 1.6 2014/07/10 22:45:57 jsing Exp $ */
2
/*
3
 * Originally written by Bodo Moeller for the OpenSSL project.
4
 */
5
/* ====================================================================
6
 * Copyright (c) 1998-2002 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
 *
61
 * Portions of the attached software ("Contribution") are developed by
62
 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
63
 *
64
 * The Contribution is licensed pursuant to the OpenSSL open source
65
 * license provided above.
66
 *
67
 * The elliptic curve binary polynomial software is originally written by
68
 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories.
69
 *
70
 */
71
72
#include <openssl/opensslconf.h>
73
74
#include <openssl/err.h>
75
#include "ec_lcl.h"
76
77
EC_GROUP *
78
EC_GROUP_new_curve_GFp(const BIGNUM *p, const BIGNUM *a, const BIGNUM *b,
79
    BN_CTX *ctx)
80
{
81
	const EC_METHOD *meth;
82
	EC_GROUP *ret;
83
84
#if defined(OPENSSL_BN_ASM_MONT)
85
	/*
86
	 * This might appear controversial, but the fact is that generic
87
	 * prime method was observed to deliver better performance even
88
	 * for NIST primes on a range of platforms, e.g.: 60%-15%
89
	 * improvement on IA-64, ~25% on ARM, 30%-90% on P4, 20%-25%
90
	 * in 32-bit build and 35%--12% in 64-bit build on Core2...
91
	 * Coefficients are relative to optimized bn_nist.c for most
92
	 * intensive ECDSA verify and ECDH operations for 192- and 521-
93
	 * bit keys respectively. Choice of these boundary values is
94
	 * arguable, because the dependency of improvement coefficient
95
	 * from key length is not a "monotone" curve. For example while
96
	 * 571-bit result is 23% on ARM, 384-bit one is -1%. But it's
97
	 * generally faster, sometimes "respectfully" faster, sometimes
98
	 * "tolerably" slower... What effectively happens is that loop
99
	 * with bn_mul_add_words is put against bn_mul_mont, and the
100
	 * latter "wins" on short vectors. Correct solution should be
101
	 * implementing dedicated NxN multiplication subroutines for
102
	 * small N. But till it materializes, let's stick to generic
103
	 * prime method...
104
	 *						<appro>
105
	 */
106
4464
	meth = EC_GFp_mont_method();
107
#else
108
	meth = EC_GFp_nist_method();
109
#endif
110
111
2232
	ret = EC_GROUP_new(meth);
112
2232
	if (ret == NULL)
113
		return NULL;
114
115
2232
	if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) {
116
		unsigned long err;
117
118
		err = ERR_peek_last_error();
119
120
		if (!(ERR_GET_LIB(err) == ERR_LIB_EC &&
121
		    ((ERR_GET_REASON(err) == EC_R_NOT_A_NIST_PRIME) ||
122
		    (ERR_GET_REASON(err) == EC_R_NOT_A_SUPPORTED_NIST_PRIME)))) {
123
			/* real error */
124
125
			EC_GROUP_clear_free(ret);
126
			return NULL;
127
		}
128
		/* not an actual error, we just cannot use EC_GFp_nist_method */
129
130
		ERR_clear_error();
131
132
		EC_GROUP_clear_free(ret);
133
		meth = EC_GFp_mont_method();
134
135
		ret = EC_GROUP_new(meth);
136
		if (ret == NULL)
137
			return NULL;
138
139
		if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) {
140
			EC_GROUP_clear_free(ret);
141
			return NULL;
142
		}
143
	}
144
2232
	return ret;
145
2232
}
146
147
#ifndef OPENSSL_NO_EC2M
148
EC_GROUP *
149
EC_GROUP_new_curve_GF2m(const BIGNUM *p, const BIGNUM *a, const BIGNUM *b,
150
    BN_CTX *ctx)
151
{
152
	const EC_METHOD *meth;
153
	EC_GROUP *ret;
154
155
1190
	meth = EC_GF2m_simple_method();
156
157
595
	ret = EC_GROUP_new(meth);
158
595
	if (ret == NULL)
159
		return NULL;
160
161
595
	if (!EC_GROUP_set_curve_GF2m(ret, p, a, b, ctx)) {
162
		EC_GROUP_clear_free(ret);
163
		return NULL;
164
	}
165
595
	return ret;
166
595
}
167
#endif