+The cryptodev library currently provides support for the following asymmetric
+Crypto operations; RSA, Modular exponentiation and inversion, Diffie-Hellman
+public and/or private key generation and shared secret compute, DSA Signature
+generation and verification.
+
+Session and Session Management
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Sessions are used in asymmetric cryptographic processing to store the immutable
+data defined in asymmetric cryptographic transform which is further used in the
+operation processing. Sessions typically stores information, such as, public
+and private key information or domain params or prime modulus data i.e. immutable
+across data sets. Crypto sessions cache this immutable data in a optimal way for the
+underlying PMD and this allows further acceleration of the offload of Crypto workloads.
+
+Like symmetric, the Crypto device framework provides APIs to allocate and initialize
+asymmetric sessions for crypto devices, where sessions are mempool objects.
+It is the application's responsibility to create and manage the session mempools.
+Application using both symmetric and asymmetric sessions should allocate and maintain
+different sessions pools for each type.
+
+An application can use ``rte_cryptodev_get_asym_session_private_size()`` to
+get the private size of asymmetric session on a given crypto device. This
+function would allow an application to calculate the max device asymmetric
+session size of all crypto devices to create a single session mempool.
+If instead an application creates multiple asymmetric session mempools,
+the Crypto device framework also provides ``rte_cryptodev_asym_get_header_session_size()`` to get
+the size of an uninitialized session.
+
+Once the session mempools have been created, ``rte_cryptodev_asym_session_create()``
+is used to allocate an uninitialized asymmetric session from the given mempool.
+The session then must be initialized using ``rte_cryptodev_asym_session_init()``
+for each of the required crypto devices. An asymmetric transform chain
+is used to specify the operation and its parameters. See the section below for
+details on transforms.
+
+When a session is no longer used, user must call ``rte_cryptodev_asym_session_clear()``
+for each of the crypto devices that are using the session, to free all driver
+private asymmetric session data. Once this is done, session should be freed using
+``rte_cryptodev_asym_session_free()`` which returns them to their mempool.
+
+Asymmetric Sessionless Support
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Currently asymmetric crypto framework does not support sessionless.
+
+Transforms and Transform Chaining
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Asymmetric Crypto transforms (``rte_crypto_asym_xform``) are the mechanism used
+to specify the details of the asymmetric Crypto operation. Next pointer within
+xform allows transform to be chained together. Also it is important to note that
+the order in which the transforms are passed indicates the order of the chaining.
+
+Not all asymmetric crypto xforms are supported for chaining. Currently supported
+asymmetric crypto chaining is Diffie-Hellman private key generation followed by
+public generation. Also, currently API does not support chaining of symmetric and
+asymmetric crypto xfroms.
+
+Each xform defines specific asymmetric crypto algo. Currently supported are:
+* RSA
+* Modular operations (Exponentiation and Inverse)
+* Diffie-Hellman
+* DSA
+* None - special case where PMD may support a passthrough mode. More for diagnostic purpose
+
+See *DPDK API Reference* for details on each rte_crypto_xxx_xform struct
+
+Asymmetric Operations
+~~~~~~~~~~~~~~~~~~~~~
+
+The asymmetric Crypto operation structure contains all the mutable data relating
+to asymmetric cryptographic processing on an input data buffer. It uses either
+RSA, Modular, Diffie-Hellman or DSA operations depending upon session it is attached
+to.
+
+Every operation must carry a valid session handle which further carries information
+on xform or xform-chain to be performed on op. Every xform type defines its own set
+of operational params in their respective rte_crypto_xxx_op_param struct. Depending
+on xform information within session, PMD picks up and process respective op_param
+struct.
+Unlike symmetric, asymmetric operations do not use mbufs for input/output.
+They operate on data buffer of type ``rte_crypto_param``.
+
+See *DPDK API Reference* for details on each rte_crypto_xxx_op_param struct
+
+Asymmetric crypto Sample code
+-----------------------------
+
+There's a unit test application test_cryptodev_asym.c inside unit test framework that
+show how to setup and process asymmetric operations using cryptodev library.
+
+The following sample code shows the basic steps to compute modular exponentiation
+using 1024-bit modulus length using openssl PMD available in DPDK (performing other
+crypto operations is similar except change to respective op and xform setup).
+
+.. code-block:: c
+
+ /*
+ * Simple example to compute modular exponentiation with 1024-bit key
+ *
+ */
+ #define MAX_ASYM_SESSIONS 10
+ #define NUM_ASYM_BUFS 10
+
+ struct rte_mempool *crypto_op_pool, *asym_session_pool;
+ unsigned int asym_session_size;
+ int ret;
+
+ /* Initialize EAL. */
+ ret = rte_eal_init(argc, argv);
+ if (ret < 0)
+ rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
+
+ uint8_t socket_id = rte_socket_id();
+
+ /* Create crypto operation pool. */
+ crypto_op_pool = rte_crypto_op_pool_create(
+ "crypto_op_pool",
+ RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
+ NUM_ASYM_BUFS, 0, 0,
+ socket_id);
+ if (crypto_op_pool == NULL)
+ rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
+
+ /* Create the virtual crypto device. */
+ char args[128];
+ const char *crypto_name = "crypto_openssl";
+ snprintf(args, sizeof(args), "socket_id=%d", socket_id);
+ ret = rte_vdev_init(crypto_name, args);
+ if (ret != 0)
+ rte_exit(EXIT_FAILURE, "Cannot create virtual device");
+
+ uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
+
+ /* Get private asym session data size. */
+ asym_session_size = rte_cryptodev_get_asym_private_session_size(cdev_id);