| 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 |  | 158 | { | 
    
    | 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 |  | 158 | 	meth = EC_GFp_mont_method(); | 
    
    | 107 |  |  | #else | 
    
    | 108 |  |  | 	meth = EC_GFp_nist_method(); | 
    
    | 109 |  |  | #endif | 
    
    | 110 |  |  |  | 
    
    | 111 |  | 158 | 	ret = EC_GROUP_new(meth); | 
    
    | 112 | ✗✓ | 158 | 	if (ret == NULL) | 
    
    | 113 |  |  | 		return NULL; | 
    
    | 114 |  |  |  | 
    
    | 115 | ✗✓ | 158 | 	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 |  | 158 | 	return ret; | 
    
    | 145 |  |  | } | 
    
    | 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 |  | 137 | { | 
    
    | 152 |  |  | 	const EC_METHOD *meth; | 
    
    | 153 |  |  | 	EC_GROUP *ret; | 
    
    | 154 |  |  |  | 
    
    | 155 |  | 137 | 	meth = EC_GF2m_simple_method(); | 
    
    | 156 |  |  |  | 
    
    | 157 |  | 137 | 	ret = EC_GROUP_new(meth); | 
    
    | 158 | ✗✓ | 137 | 	if (ret == NULL) | 
    
    | 159 |  |  | 		return NULL; | 
    
    | 160 |  |  |  | 
    
    | 161 | ✗✓ | 137 | 	if (!EC_GROUP_set_curve_GF2m(ret, p, a, b, ctx)) { | 
    
    | 162 |  |  | 		EC_GROUP_clear_free(ret); | 
    
    | 163 |  |  | 		return NULL; | 
    
    | 164 |  |  | 	} | 
    
    | 165 |  | 137 | 	return ret; | 
    
    | 166 |  |  | } | 
    
    | 167 |  |  | #endif |