* crypto_transfer_hash_request_to_engine()
+* crypto_transfer_kpp_request_to_engine()
+
* crypto_transfer_skcipher_request_to_engine()
At the end of the request process, a call to one of the following functions is needed:
* crypto_finalize_hash_request()
+* crypto_finalize_kpp_request()
+
* crypto_finalize_skcipher_request()