static int rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
{
    unsigned char *rk = NULL;
    int rklen;
    rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);

    if (rklen <= 0) {
        RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
        return 0;
    }

    if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_rsaEncryption), 0,
                         V_ASN1_NULL, NULL, rk, rklen)) {
        RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
        return 0;
    }

    return 1;
}

Unknown