GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcrypto/ec/ec_cvt.c Lines: 12 31 38.7 %
Date: 2017-11-07 Branches: 4 20 20.0 %

Line Branch Exec Source
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/* $OpenBSD: ec_cvt.c,v 1.6 2014/07/10 22:45:57 jsing Exp $ */
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/*
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 * Originally written by Bodo Moeller for the OpenSSL project.
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 */
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/* ====================================================================
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 * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 *
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 *
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in
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 *    the documentation and/or other materials provided with the
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 *    distribution.
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 *
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 * 3. All advertising materials mentioning features or use of this
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 *    software must display the following acknowledgment:
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 *    "This product includes software developed by the OpenSSL Project
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 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
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 *
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 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
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 *    endorse or promote products derived from this software without
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 *    prior written permission. For written permission, please contact
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 *    openssl-core@openssl.org.
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 *
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 * 5. Products derived from this software may not be called "OpenSSL"
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 *    nor may "OpenSSL" appear in their names without prior written
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 *    permission of the OpenSSL Project.
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 *
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 * 6. Redistributions of any form whatsoever must retain the following
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 *    acknowledgment:
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 *    "This product includes software developed by the OpenSSL Project
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 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
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 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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 * OF THE POSSIBILITY OF SUCH DAMAGE.
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 * ====================================================================
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 *
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 * This product includes cryptographic software written by Eric Young
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 * (eay@cryptsoft.com).  This product includes software written by Tim
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 * Hudson (tjh@cryptsoft.com).
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 *
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 */
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/* ====================================================================
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 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
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 *
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 * Portions of the attached software ("Contribution") are developed by
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 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
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 *
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 * The Contribution is licensed pursuant to the OpenSSL open source
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 * license provided above.
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 *
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 * The elliptic curve binary polynomial software is originally written by
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 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories.
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 *
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 */
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#include <openssl/opensslconf.h>
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#include <openssl/err.h>
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#include "ec_lcl.h"
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EC_GROUP *
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EC_GROUP_new_curve_GFp(const BIGNUM *p, const BIGNUM *a, const BIGNUM *b,
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    BN_CTX *ctx)
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{
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	const EC_METHOD *meth;
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	EC_GROUP *ret;
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#if defined(OPENSSL_BN_ASM_MONT)
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	/*
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	 * This might appear controversial, but the fact is that generic
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	 * prime method was observed to deliver better performance even
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	 * for NIST primes on a range of platforms, e.g.: 60%-15%
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	 * improvement on IA-64, ~25% on ARM, 30%-90% on P4, 20%-25%
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	 * in 32-bit build and 35%--12% in 64-bit build on Core2...
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	 * Coefficients are relative to optimized bn_nist.c for most
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	 * intensive ECDSA verify and ECDH operations for 192- and 521-
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	 * bit keys respectively. Choice of these boundary values is
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	 * arguable, because the dependency of improvement coefficient
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	 * from key length is not a "monotone" curve. For example while
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	 * 571-bit result is 23% on ARM, 384-bit one is -1%. But it's
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	 * generally faster, sometimes "respectfully" faster, sometimes
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	 * "tolerably" slower... What effectively happens is that loop
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	 * with bn_mul_add_words is put against bn_mul_mont, and the
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	 * latter "wins" on short vectors. Correct solution should be
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	 * implementing dedicated NxN multiplication subroutines for
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	 * small N. But till it materializes, let's stick to generic
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	 * prime method...
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	 *						<appro>
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	 */
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	meth = EC_GFp_mont_method();
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#else
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	meth = EC_GFp_nist_method();
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#endif
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	ret = EC_GROUP_new(meth);
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	if (ret == NULL)
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		return NULL;
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	if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) {
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		unsigned long err;
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		err = ERR_peek_last_error();
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		if (!(ERR_GET_LIB(err) == ERR_LIB_EC &&
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		    ((ERR_GET_REASON(err) == EC_R_NOT_A_NIST_PRIME) ||
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		    (ERR_GET_REASON(err) == EC_R_NOT_A_SUPPORTED_NIST_PRIME)))) {
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			/* real error */
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			EC_GROUP_clear_free(ret);
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			return NULL;
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		}
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		/* not an actual error, we just cannot use EC_GFp_nist_method */
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		ERR_clear_error();
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		EC_GROUP_clear_free(ret);
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		meth = EC_GFp_mont_method();
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		ret = EC_GROUP_new(meth);
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		if (ret == NULL)
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			return NULL;
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		if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) {
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			EC_GROUP_clear_free(ret);
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			return NULL;
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		}
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	}
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	return ret;
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}
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#ifndef OPENSSL_NO_EC2M
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EC_GROUP *
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EC_GROUP_new_curve_GF2m(const BIGNUM *p, const BIGNUM *a, const BIGNUM *b,
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    BN_CTX *ctx)
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{
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	const EC_METHOD *meth;
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	EC_GROUP *ret;
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	meth = EC_GF2m_simple_method();
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	ret = EC_GROUP_new(meth);
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	if (ret == NULL)
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		return NULL;
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	if (!EC_GROUP_set_curve_GF2m(ret, p, a, b, ctx)) {
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		EC_GROUP_clear_free(ret);
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		return NULL;
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	}
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	return ret;
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}
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#endif