| Current Path : /usr/opt/openssl11/share/doc/openssl/html/man3/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/opt/openssl11/share/doc/openssl/html/man3/EC_GFp_nistp224_method.html |
<?xml version="1.0" ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>EC_GFp_simple_method</title> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <link rev="made" href="mailto:root@hsxx.drive.ne.jp" /> </head> <body style="background-color: white"> <!-- INDEX BEGIN --> <div name="index"> <p><a name="__index__"></a></p> <ul> <li><a href="#name">NAME</a></li> <li><a href="#synopsis">SYNOPSIS</a></li> <li><a href="#description">DESCRIPTION</a></li> <li><a href="#return_values">RETURN VALUES</a></li> <li><a href="#see_also">SEE ALSO</a></li> <li><a href="#copyright">COPYRIGHT</a></li> </ul> <hr name="index" /> </div> <!-- INDEX END --> <p> </p> <hr /> <h1><a name="name">NAME</a></h1> <p>EC_GFp_simple_method, EC_GFp_mont_method, EC_GFp_nist_method, EC_GFp_nistp224_method, EC_GFp_nistp256_method, EC_GFp_nistp521_method, EC_GF2m_simple_method, EC_METHOD_get_field_type - Functions for obtaining EC_METHOD objects</p> <p> </p> <hr /> <h1><a name="synopsis">SYNOPSIS</a></h1> <pre> #include <openssl/ec.h></pre> <pre> const EC_METHOD *EC_GFp_simple_method(void); const EC_METHOD *EC_GFp_mont_method(void); const EC_METHOD *EC_GFp_nist_method(void); const EC_METHOD *EC_GFp_nistp224_method(void); const EC_METHOD *EC_GFp_nistp256_method(void); const EC_METHOD *EC_GFp_nistp521_method(void);</pre> <pre> const EC_METHOD *EC_GF2m_simple_method(void);</pre> <pre> int EC_METHOD_get_field_type(const EC_METHOD *meth);</pre> <p> </p> <hr /> <h1><a name="description">DESCRIPTION</a></h1> <p>The Elliptic Curve library provides a number of different implementations through a single common interface. When constructing a curve using EC_GROUP_new (see <em>EC_GROUP_new(3)</em>) an implementation method must be provided. The functions described here all return a const pointer to an <strong>EC_METHOD</strong> structure that can be passed to EC_GROUP_NEW. It is important that the correct implementation type for the form of curve selected is used.</p> <p>For F2^m curves there is only one implementation choice, i.e. EC_GF2_simple_method.</p> <p>For Fp curves the lowest common denominator implementation is the EC_GFp_simple_method implementation. All other implementations are based on this one. EC_GFp_mont_method builds on EC_GFp_simple_method but adds the use of montgomery multiplication (see <em>BN_mod_mul_montgomery(3)</em>). EC_GFp_nist_method offers an implementation optimised for use with NIST recommended curves (NIST curves are available through EC_GROUP_new_by_curve_name as described in <em>EC_GROUP_new(3)</em>).</p> <p>The functions EC_GFp_nistp224_method, EC_GFp_nistp256_method and EC_GFp_nistp521_method offer 64 bit optimised implementations for the NIST P224, P256 and P521 curves respectively. Note, however, that these implementations are not available on all platforms.</p> <p>EC_METHOD_get_field_type identifies what type of field the EC_METHOD structure supports, which will be either F2^m or Fp. If the field type is Fp then the value <strong>NID_X9_62_prime_field</strong> is returned. If the field type is F2^m then the value <strong>NID_X9_62_characteristic_two_field</strong> is returned. These values are defined in the obj_mac.h header file.</p> <p> </p> <hr /> <h1><a name="return_values">RETURN VALUES</a></h1> <p>All EC_GFp* functions and EC_GF2m_simple_method always return a const pointer to an EC_METHOD structure.</p> <p>EC_METHOD_get_field_type returns an integer that identifies the type of field the EC_METHOD structure supports.</p> <p> </p> <hr /> <h1><a name="see_also">SEE ALSO</a></h1> <p><em>crypto(7)</em>, <em>EC_GROUP_new(3)</em>, <em>EC_GROUP_copy(3)</em>, <em>EC_POINT_new(3)</em>, <em>EC_POINT_add(3)</em>, <em>EC_KEY_new(3)</em>, <em>d2i_ECPKParameters(3)</em>, <em>BN_mod_mul_montgomery(3)</em></p> <p> </p> <hr /> <h1><a name="copyright">COPYRIGHT</a></h1> <p>Copyright 2013-2017 The OpenSSL Project Authors. All Rights Reserved.</p> <p>Licensed under the OpenSSL license (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <a href="https://www.openssl.org/source/license.html">https://www.openssl.org/source/license.html</a>.</p> </body> </html>