NAME¶
i2d_ECPrivateKey, d2i_ECPrivate_key - Encode and decode functions for saving and
reading EC_KEY structures
SYNOPSIS¶
#include <openssl/ec.h>
EC_KEY *d2i_ECPrivateKey(EC_KEY **key, const unsigned char **in, long len);
int i2d_ECPrivateKey(EC_KEY *key, unsigned char **out);
unsigned int EC_KEY_get_enc_flags(const EC_KEY *key);
void EC_KEY_set_enc_flags(EC_KEY *eckey, unsigned int flags);
DESCRIPTION¶
The ECPrivateKey encode and decode routines encode and parse an
EC_KEY
structure into a binary format (ASN.1 DER) and back again.
These functions are similar to the
d2i_X509() functions, and you should
refer to that page for a detailed description (see
d2i_X509(3)).
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
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
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
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.
RETURN VALUES¶
d2i_ECPrivateKey() returns a valid
EC_KEY structure or
NULL
if an error occurs. The error code that can be obtained by
ERR_get_error(3).
i2d_ECPrivateKey() returns the number of bytes successfully encoded or a
negative value if an error occurs. The error code can be obtained by
ERR_get_error(3).
EC_KEY_get_enc_flags returns the value of the current encoding flags for the
EC_KEY.
SEE ALSO¶
crypto(3),
ec(3),
EC_GROUP_new(3),
EC_GROUP_copy(3),
EC_POINT_new(3),
EC_POINT_add(3),
EC_GFp_simple_method(3),
d2i_ECPKParameters(3),
d2i_ECPrivateKey(3)