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+=pod
+
+=head1 NAME
+
+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
+
+=head1 SYNOPSIS
+
+ #include <openssl/ec.h>
+
+ 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);
+
+ const EC_METHOD *EC_GF2m_simple_method(void);
+
+ int EC_METHOD_get_field_type(const EC_METHOD *meth);
+
+=head1 DESCRIPTION
+
+The Elliptic Curve library provides a number of different implementations through a single common interface.
+When constructing a curve using EC_GROUP_new (see L<EC_GROUP_new(3)>) an
+implementation method must be provided. The functions described here all return a const pointer to an
+B<EC_METHOD> 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.
+
+For F2^m curves there is only one implementation choice, i.e. EC_GF2_simple_method.
+
+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 L<BN_mod_mul_montgomery(3)>). 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 L<EC_GROUP_new(3)>).
+
+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.
+
+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 B<NID_X9_62_prime_field> is returned. If the field type is
+F2^m then the value B<NID_X9_62_characteristic_two_field> is returned. These values are defined in the
+obj_mac.h header file.
+
+=head1 RETURN VALUES
+
+All EC_GFp* functions and EC_GF2m_simple_method always return a const pointer to an EC_METHOD structure.
+
+EC_METHOD_get_field_type returns an integer that identifies the type of field the EC_METHOD structure supports.
+
+=head1 SEE ALSO
+
+L<crypto(7)>, L<EC_GROUP_new(3)>, L<EC_GROUP_copy(3)>,
+L<EC_POINT_new(3)>, L<EC_POINT_add(3)>, L<EC_KEY_new(3)>,
+L<d2i_ECPKParameters(3)>,
+L<BN_mod_mul_montgomery(3)>
+
+=head1 COPYRIGHT
+
+Copyright 2013-2017 The OpenSSL Project Authors. All Rights Reserved.
+
+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
+L<https://www.openssl.org/source/license.html>.
+
+=cut