1EC_GFP_SIMPLE_METHOD(3ossl)         OpenSSL        EC_GFP_SIMPLE_METHOD(3ossl)
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NAME

6       EC_GFp_simple_method, EC_GFp_mont_method, EC_GFp_nist_method,
7       EC_GFp_nistp224_method, EC_GFp_nistp256_method, EC_GFp_nistp521_method,
8       EC_GF2m_simple_method, EC_METHOD_get_field_type - Functions for
9       obtaining EC_METHOD objects
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SYNOPSIS

12        #include <openssl/ec.h>
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14       The following functions have been deprecated since OpenSSL 3.0, and can
15       be hidden entirely by defining OPENSSL_API_COMPAT with a suitable
16       version value, see openssl_user_macros(7):
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18        const EC_METHOD *EC_GFp_simple_method(void);
19        const EC_METHOD *EC_GFp_mont_method(void);
20        const EC_METHOD *EC_GFp_nist_method(void);
21        const EC_METHOD *EC_GFp_nistp224_method(void);
22        const EC_METHOD *EC_GFp_nistp256_method(void);
23        const EC_METHOD *EC_GFp_nistp521_method(void);
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25        const EC_METHOD *EC_GF2m_simple_method(void);
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27        int EC_METHOD_get_field_type(const EC_METHOD *meth);
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DESCRIPTION

30       All const EC_METHOD *EC_GF* functions were deprecated in OpenSSL 3.0,
31       since EC_METHOD is no longer a public concept.
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33       The Elliptic Curve library provides a number of different
34       implementations through a single common interface.  When constructing a
35       curve using EC_GROUP_new (see EC_GROUP_new(3)) an implementation method
36       must be provided. The functions described here all return a const
37       pointer to an EC_METHOD structure that can be passed to EC_GROUP_NEW.
38       It is important that the correct implementation type for the form of
39       curve selected is used.
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41       For F2^m curves there is only one implementation choice, i.e.
42       EC_GF2_simple_method.
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44       For Fp curves the lowest common denominator implementation is the
45       EC_GFp_simple_method implementation. All other implementations are
46       based on this one. EC_GFp_mont_method builds on EC_GFp_simple_method
47       but adds the use of montgomery multiplication (see
48       BN_mod_mul_montgomery(3)). EC_GFp_nist_method offers an implementation
49       optimised for use with NIST recommended curves (NIST curves are
50       available through EC_GROUP_new_by_curve_name as described in
51       EC_GROUP_new(3)).
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53       The functions EC_GFp_nistp224_method, EC_GFp_nistp256_method and
54       EC_GFp_nistp521_method offer 64 bit optimised implementations for the
55       NIST P224, P256 and P521 curves respectively. Note, however, that these
56       implementations are not available on all platforms.
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58       EC_METHOD_get_field_type() was deprecated in OpenSSL 3.0.  Applications
59       should use EC_GROUP_get_field_type() as a replacement (see
60       EC_GROUP_copy(3)).
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RETURN VALUES

63       All EC_GFp* functions and EC_GF2m_simple_method always return a const
64       pointer to an EC_METHOD structure.
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66       EC_METHOD_get_field_type returns an integer that identifies the type of
67       field the EC_METHOD structure supports.
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SEE ALSO

70       crypto(7), EC_GROUP_new(3), EC_GROUP_copy(3), EC_POINT_new(3),
71       EC_POINT_add(3), EC_KEY_new(3), d2i_ECPKParameters(3),
72       BN_mod_mul_montgomery(3)
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HISTORY

75       EC_GFp_simple_method(), EC_GFp_mont_method(void), EC_GFp_nist_method(),
76       EC_GFp_nistp224_method(), EC_GFp_nistp256_method(),
77       EC_GFp_nistp521_method(), EC_GF2m_simple_method(), and
78       EC_METHOD_get_field_type() were deprecated in OpenSSL 3.0.
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81       Copyright 2013-2021 The OpenSSL Project Authors. All Rights Reserved.
82
83       Licensed under the Apache License 2.0 (the "License").  You may not use
84       this file except in compliance with the License.  You can obtain a copy
85       in the file LICENSE in the source distribution or at
86       <https://www.openssl.org/source/license.html>.
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903.0.9                             2023-07-27       EC_GFP_SIMPLE_METHOD(3ossl)
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