#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);
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.
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 https://www.openssl.org/source/license.html.