nest-open-source / nest-connect / 1.0 / emssl / a69f9a52fc8aed7da65df36050b3ffbb6b453db2 / . / openssl / ec / ec_cvt.c

/* crypto/ec/ec_cvt.c */ | |

/* | |

* Originally written by Bodo Moeller for the OpenSSL project. | |

*/ | |

/* ==================================================================== | |

* Copyright (c) 1998-2002 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 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. | |

* | |

* Portions of the attached software ("Contribution") are developed by | |

* SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. | |

* | |

* The Contribution is licensed pursuant to the OpenSSL open source | |

* license provided above. | |

* | |

* The elliptic curve binary polynomial software is originally written by | |

* Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories. | |

* | |

*/ | |

#include <openssl/err.h> | |

#include "ec_lcl.h" | |

EC_GROUP *EC_GROUP_new_curve_GFp(const BIGNUM *p, const BIGNUM *a, | |

const BIGNUM *b, BN_CTX *ctx) | |

{ | |

const EC_METHOD *meth; | |

EC_GROUP *ret; | |

#ifdef FORCE_SIMPLE_EC_METHOD | |

meth = EC_GFp_simple_method(); | |

ret = EC_GROUP_new(meth); | |

if (ret == NULL) | |

return NULL; | |

if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) | |

{ | |

EC_GROUP_free(ret); | |

return NULL; | |

} | |

return ret; | |

#else /* FORCE_SIMPLE_EC_METHOD */ | |

#if defined(OPENSSL_BN_ASM_MONT) | |

/* | |

* This might appear controversial, but the fact is that generic | |

* prime method was observed to deliver better performance even | |

* for NIST primes on a range of platforms, e.g.: 60%-15% | |

* improvement on IA-64, ~25% on ARM, 30%-90% on P4, 20%-25% | |

* in 32-bit build and 35%--12% in 64-bit build on Core2... | |

* Coefficients are relative to optimized bn_nist.c for most | |

* intensive ECDSA verify and ECDH operations for 192- and 521- | |

* bit keys respectively. Choice of these boundary values is | |

* arguable, because the dependency of improvement coefficient | |

* from key length is not a "monotone" curve. For example while | |

* 571-bit result is 23% on ARM, 384-bit one is -1%. But it's | |

* generally faster, sometimes "respectfully" faster, sometimes | |

* "tolerably" slower... What effectively happens is that loop | |

* with bn_mul_add_words is put against bn_mul_mont, and the | |

* latter "wins" on short vectors. Correct solution should be | |

* implementing dedicated NxN multiplication subroutines for | |

* small N. But till it materializes, let's stick to generic | |

* prime method... | |

* <appro> | |

*/ | |

meth = EC_GFp_mont_method(); | |

#else | |

meth = EC_GFp_nist_method(); | |

#endif | |

ret = EC_GROUP_new(meth); | |

if (ret == NULL) | |

return NULL; | |

if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) { | |

unsigned long err; | |

err = ERR_peek_last_error(); | |

if (!(ERR_GET_LIB(err) == ERR_LIB_EC && | |

((ERR_GET_REASON(err) == EC_R_NOT_A_NIST_PRIME) || | |

(ERR_GET_REASON(err) == EC_R_NOT_A_SUPPORTED_NIST_PRIME)))) { | |

/* real error */ | |

EC_GROUP_clear_free(ret); | |

return NULL; | |

} | |

/* | |

* not an actual error, we just cannot use EC_GFp_nist_method | |

*/ | |

ERR_clear_error(); | |

EC_GROUP_clear_free(ret); | |

meth = EC_GFp_mont_method(); | |

ret = EC_GROUP_new(meth); | |

if (ret == NULL) | |

return NULL; | |

if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx)) { | |

EC_GROUP_clear_free(ret); | |

return NULL; | |

} | |

} | |

#endif /* FORCE_SIMPLE_EC_METHOD */ | |

return ret; | |

} | |

#ifndef OPENSSL_NO_EC2M | |

EC_GROUP *EC_GROUP_new_curve_GF2m(const BIGNUM *p, const BIGNUM *a, | |

const BIGNUM *b, BN_CTX *ctx) | |

{ | |

const EC_METHOD *meth; | |

EC_GROUP *ret; | |

meth = EC_GF2m_simple_method(); | |

ret = EC_GROUP_new(meth); | |

if (ret == NULL) | |

return NULL; | |

if (!EC_GROUP_set_curve_GF2m(ret, p, a, b, ctx)) { | |

EC_GROUP_clear_free(ret); | |

return NULL; | |

} | |

return ret; | |

} | |

#endif |