* The following functions handle keys that are stored in some secondary  * location, handled by the engine.  The storage may be on a card or  * whatever. */ EVP_PKEY *ENGINE_load_private_key(ENGINE *e, const char *key_id,  UI_METHOD *ui_method, void *callback_data); EVP_PKEY *ENGINE_load_public_key(ENGINE *e, const char *key_id,  UI_METHOD *ui_method, void *callback_data); int ENGINE_load_ssl_client_cert(ENGINE *e, SSL *s,  STACK_OF(X000_NAME) *ca_dn, X000 **pcert, EVP_PKEY **p