From: Corentin Labbe Subject: [PATCH 1/6] Documentation: crypto: document crypto engine API Date: Wed, 3 Jan 2018 21:11:04 +0100 Message-ID: <20180103201109.16077-2-clabbe.montjoie@gmail.com> References: <20180103201109.16077-1-clabbe.montjoie@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, fabien.dessenne@st.com, virtualization@lists.linux-foundation.org, Corentin Labbe , linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org To: alexandre.torgue@st.com, arei.gonglei@huawei.com, corbet@lwn.net, davem@davemloft.net, herbert@gondor.apana.org.au, jasowang@redhat.com, mcoquelin.stm32@gmail.com, mst@redhat.com Return-path: In-Reply-To: <20180103201109.16077-1-clabbe.montjoie@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: linux-crypto.vger.kernel.org Signed-off-by: Corentin Labbe --- Documentation/crypto/crypto_engine.rst | 46 ++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/crypto/crypto_engine.rst diff --git a/Documentation/crypto/crypto_engine.rst b/Documentation/crypto/crypto_engine.rst new file mode 100644 index 000000000000..b0ed37f9fb0c --- /dev/null +++ b/Documentation/crypto/crypto_engine.rst @@ -0,0 +1,46 @@ +============= +CRYPTO ENGINE +============= + +Overview +-------- +The crypto engine API (CE), is a crypto queue manager. + +Requirement +----------- +You have to put at start of your tfm_ctx the struct crypto_engine_reqctx +struct your_tfm_ctx { + struct crypto_engine_reqctx enginectx; + ... +}; +Why: Since CE manage only crypto_async_request, it cannot know the underlying +request_type and so have access only on the TFM. +So using container_of for accessing __ctx is impossible. +Furthermore, the crypto engine cannot know the "struct your_tfm_ctx", +so it must assume that crypto_engine_reqctx is at start of it. + +Order of operations +------------------- +You have to obtain a struct crypto_engine via crypto_engine_alloc_init(). +And start it via crypto_engine_start(). + +Before transferring any request, you have to fill the enginectx. +- prepare_request: (taking a function pointer) If you need to do some processing before doing the request +- unprepare_request: (taking a function pointer) Undoing what's done in prepare_request +- do_one_request: (taking a function pointer) Do encryption for current request + +Note: that those three functions get the crypto_async_request associated with the received request. +So your need to get the original request via container_of(areq, struct yourrequesttype_request, base); + +When your driver receive a crypto_request, you have to transfer it to +the cryptoengine via one of: +- crypto_transfer_cipher_request_to_engine() +- crypto_transfer_skcipher_request_to_engine() +- crypto_transfer_akcipher_request_to_engine() +- crypto_transfer_hash_request_to_engine() + +At the end of the request process, a call to one of the following function is needed: +- crypto_finalize_cipher_request +- crypto_finalize_skcipher_request +- crypto_finalize_akcipher_request +- crypto_finalize_hash_request -- 2.13.6