xref: /freebsd-src/crypto/openssl/doc/man3/EC_KEY_get_enc_flags.pod (revision b077aed33b7b6aefca7b17ddb250cf521f938613)

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=head1 NAME

EC_KEY_get_enc_flags, EC_KEY_set_enc_flags
- Get and set flags for encoding EC_KEY structures

=head1 SYNOPSIS

 #include <openssl/ec.h>

 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key);
 void EC_KEY_set_enc_flags(EC_KEY *eckey, unsigned int flags);

=head1 DESCRIPTION

The format of the external representation of the public key written by
i2d_ECPrivateKey() (such as whether it is stored in a compressed form or not) is
described by the point_conversion_form. See L<EC_GROUP_copy(3)>
for a description of point_conversion_form.

When reading a private key encoded without an associated public key (e.g. if
EC_PKEY_NO_PUBKEY has been used - see below), then d2i_ECPrivateKey() generates
the missing public key automatically. Private keys encoded without parameters
(e.g. if EC_PKEY_NO_PARAMETERS has been used - see below) cannot be loaded using
d2i_ECPrivateKey().

The functions EC_KEY_get_enc_flags() and EC_KEY_set_enc_flags() get and set the
value of the encoding flags for the B<key>. There are two encoding flags
currently defined - EC_PKEY_NO_PARAMETERS and EC_PKEY_NO_PUBKEY.  These flags
define the behaviour of how the  B<key> is converted into ASN1 in a call to
i2d_ECPrivateKey(). If EC_PKEY_NO_PARAMETERS is set then the public parameters for
the curve are not encoded along with the private key. If EC_PKEY_NO_PUBKEY is
set then the public key is not encoded along with the private key.

=head1 RETURN VALUES

EC_KEY_get_enc_flags() returns the value of the current encoding flags for the
EC_KEY.

=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_GFp_simple_method(3)>,
L<d2i_ECPKParameters(3)>,
L<d2i_ECPrivateKey(3)>

=head1 COPYRIGHT

Copyright 2015-2017 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (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>.

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