xref: /dpdk/doc/guides/prog_guide/cryptodev_lib.rst (revision f399b0171e6e64c8bbce42599afa35591a9d28f1)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2016-2020 Intel Corporation.
3
4Cryptography Device Library
5===========================
6
7The cryptodev library provides a Crypto device framework for management and
8provisioning of hardware and software Crypto poll mode drivers, defining generic
9APIs which support a number of different Crypto operations. The framework
10currently only supports cipher, authentication, chained cipher/authentication
11and AEAD symmetric and asymmetric Crypto operations.
12
13
14Design Principles
15-----------------
16
17The cryptodev library follows the same basic principles as those used in DPDK's
18Ethernet Device framework. The Crypto framework provides a generic Crypto device
19framework which supports both physical (hardware) and virtual (software) Crypto
20devices as well as a generic Crypto API which allows Crypto devices to be
21managed and configured and supports Crypto operations to be provisioned on
22Crypto poll mode driver.
23
24
25Device Management
26-----------------
27
28Device Creation
29~~~~~~~~~~~~~~~
30
31Physical Crypto devices are discovered during the PCI probe/enumeration of the
32EAL function which is executed at DPDK initialization, based on
33their PCI device identifier, each unique PCI BDF (bus/bridge, device,
34function). Specific physical Crypto devices, like other physical devices in DPDK
35can be white-listed or black-listed using the EAL command line options.
36
37Virtual devices can be created by two mechanisms, either using the EAL command
38line options or from within the application using an EAL API directly.
39
40From the command line using the --vdev EAL option
41
42.. code-block:: console
43
44   --vdev  'crypto_aesni_mb0,max_nb_queue_pairs=2,socket_id=0'
45
46.. Note::
47
48   * If DPDK application requires multiple software crypto PMD devices then required
49     number of ``--vdev`` with appropriate libraries are to be added.
50
51   * An Application with crypto PMD instances sharing the same library requires unique ID.
52
53   Example: ``--vdev  'crypto_aesni_mb0' --vdev  'crypto_aesni_mb1'``
54
55Or using the rte_vdev_init API within the application code.
56
57.. code-block:: c
58
59   rte_vdev_init("crypto_aesni_mb",
60                     "max_nb_queue_pairs=2,socket_id=0")
61
62All virtual Crypto devices support the following initialization parameters:
63
64* ``max_nb_queue_pairs`` - maximum number of queue pairs supported by the device.
65* ``socket_id`` - socket on which to allocate the device resources on.
66
67
68Device Identification
69~~~~~~~~~~~~~~~~~~~~~
70
71Each device, whether virtual or physical is uniquely designated by two
72identifiers:
73
74- A unique device index used to designate the Crypto device in all functions
75  exported by the cryptodev API.
76
77- A device name used to designate the Crypto device in console messages, for
78  administration or debugging purposes. For ease of use, the port name includes
79  the port index.
80
81
82Device Configuration
83~~~~~~~~~~~~~~~~~~~~
84
85The configuration of each Crypto device includes the following operations:
86
87- Allocation of resources, including hardware resources if a physical device.
88- Resetting the device into a well-known default state.
89- Initialization of statistics counters.
90
91The rte_cryptodev_configure API is used to configure a Crypto device.
92
93.. code-block:: c
94
95   int rte_cryptodev_configure(uint8_t dev_id,
96                               struct rte_cryptodev_config *config)
97
98The ``rte_cryptodev_config`` structure is used to pass the configuration
99parameters for socket selection and number of queue pairs.
100
101.. code-block:: c
102
103    struct rte_cryptodev_config {
104        int socket_id;
105        /**< Socket to allocate resources on */
106        uint16_t nb_queue_pairs;
107        /**< Number of queue pairs to configure on device */
108    };
109
110
111Configuration of Queue Pairs
112~~~~~~~~~~~~~~~~~~~~~~~~~~~~
113
114Each Crypto devices queue pair is individually configured through the
115``rte_cryptodev_queue_pair_setup`` API.
116Each queue pairs resources may be allocated on a specified socket.
117
118.. code-block:: c
119
120    int rte_cryptodev_queue_pair_setup(uint8_t dev_id, uint16_t queue_pair_id,
121                const struct rte_cryptodev_qp_conf *qp_conf,
122                int socket_id)
123
124   struct rte_cryptodev_qp_conf {
125        uint32_t nb_descriptors; /**< Number of descriptors per queue pair */
126        struct rte_mempool *mp_session;
127        /**< The mempool for creating session in sessionless mode */
128        struct rte_mempool *mp_session_private;
129        /**< The mempool for creating sess private data in sessionless mode */
130    };
131
132
133The fields ``mp_session`` and ``mp_session_private`` are used for creating
134temporary session to process the crypto operations in the session-less mode.
135They can be the same other different mempools. Please note not all Cryptodev
136PMDs supports session-less mode.
137
138
139Logical Cores, Memory and Queues Pair Relationships
140~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
141
142The Crypto device Library as the Poll Mode Driver library support NUMA for when
143a processor’s logical cores and interfaces utilize its local memory. Therefore
144Crypto operations, and in the case of symmetric Crypto operations, the session
145and the mbuf being operated on, should be allocated from memory pools created
146in the local memory. The buffers should, if possible, remain on the local
147processor to obtain the best performance results and buffer descriptors should
148be populated with mbufs allocated from a mempool allocated from local memory.
149
150The run-to-completion model also performs better, especially in the case of
151virtual Crypto devices, if the Crypto operation and session and data buffer is
152in local memory instead of a remote processor's memory. This is also true for
153the pipe-line model provided all logical cores used are located on the same
154processor.
155
156Multiple logical cores should never share the same queue pair for enqueuing
157operations or dequeuing operations on the same Crypto device since this would
158require global locks and hinder performance. It is however possible to use a
159different logical core to dequeue an operation on a queue pair from the logical
160core which it was enqueued on. This means that a crypto burst enqueue/dequeue
161APIs are a logical place to transition from one logical core to another in a
162packet processing pipeline.
163
164
165Device Features and Capabilities
166---------------------------------
167
168Crypto devices define their functionality through two mechanisms, global device
169features and algorithm capabilities. Global devices features identify device
170wide level features which are applicable to the whole device such as
171the device having hardware acceleration or supporting symmetric and/or asymmetric
172Crypto operations.
173
174The capabilities mechanism defines the individual algorithms/functions which
175the device supports, such as a specific symmetric Crypto cipher,
176authentication operation or Authenticated Encryption with Associated Data
177(AEAD) operation.
178
179
180Device Features
181~~~~~~~~~~~~~~~
182
183Currently the following Crypto device features are defined:
184
185* Symmetric Crypto operations
186* Asymmetric Crypto operations
187* Chaining of symmetric Crypto operations
188* SSE accelerated SIMD vector operations
189* AVX accelerated SIMD vector operations
190* AVX2 accelerated SIMD vector operations
191* AESNI accelerated instructions
192* Hardware off-load processing
193
194
195Device Operation Capabilities
196~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
197
198Crypto capabilities which identify particular algorithm which the Crypto PMD
199supports are  defined by the operation type, the operation transform, the
200transform identifier and then the particulars of the transform. For the full
201scope of the Crypto capability see the definition of the structure in the
202*DPDK API Reference*.
203
204.. code-block:: c
205
206   struct rte_cryptodev_capabilities;
207
208Each Crypto poll mode driver defines its own private array of capabilities
209for the operations it supports. Below is an example of the capabilities for a
210PMD which supports the authentication algorithm SHA1_HMAC and the cipher
211algorithm AES_CBC.
212
213.. code-block:: c
214
215    static const struct rte_cryptodev_capabilities pmd_capabilities[] = {
216        {    /* SHA1 HMAC */
217            .op = RTE_CRYPTO_OP_TYPE_SYMMETRIC,
218            .sym = {
219                .xform_type = RTE_CRYPTO_SYM_XFORM_AUTH,
220                .auth = {
221                    .algo = RTE_CRYPTO_AUTH_SHA1_HMAC,
222                    .block_size = 64,
223                    .key_size = {
224                        .min = 64,
225                        .max = 64,
226                        .increment = 0
227                    },
228                    .digest_size = {
229                        .min = 12,
230                        .max = 12,
231                        .increment = 0
232                    },
233                    .aad_size = { 0 },
234                    .iv_size = { 0 }
235                }
236            }
237        },
238        {    /* AES CBC */
239            .op = RTE_CRYPTO_OP_TYPE_SYMMETRIC,
240            .sym = {
241                .xform_type = RTE_CRYPTO_SYM_XFORM_CIPHER,
242                .cipher = {
243                    .algo = RTE_CRYPTO_CIPHER_AES_CBC,
244                    .block_size = 16,
245                    .key_size = {
246                        .min = 16,
247                        .max = 32,
248                        .increment = 8
249                    },
250                    .iv_size = {
251                        .min = 16,
252                        .max = 16,
253                        .increment = 0
254                    }
255                }
256            }
257        }
258    }
259
260
261Capabilities Discovery
262~~~~~~~~~~~~~~~~~~~~~~
263
264Discovering the features and capabilities of a Crypto device poll mode driver
265is achieved through the ``rte_cryptodev_info_get`` function.
266
267.. code-block:: c
268
269   void rte_cryptodev_info_get(uint8_t dev_id,
270                               struct rte_cryptodev_info *dev_info);
271
272This allows the user to query a specific Crypto PMD and get all the device
273features and capabilities. The ``rte_cryptodev_info`` structure contains all the
274relevant information for the device.
275
276.. code-block:: c
277
278    struct rte_cryptodev_info {
279        const char *driver_name;
280        uint8_t driver_id;
281        struct rte_device *device;
282
283        uint64_t feature_flags;
284
285        const struct rte_cryptodev_capabilities *capabilities;
286
287        unsigned max_nb_queue_pairs;
288
289        struct {
290            unsigned max_nb_sessions;
291        } sym;
292    };
293
294
295Operation Processing
296--------------------
297
298Scheduling of Crypto operations on DPDK's application data path is
299performed using a burst oriented asynchronous API set. A queue pair on a Crypto
300device accepts a burst of Crypto operations using enqueue burst API. On physical
301Crypto devices the enqueue burst API will place the operations to be processed
302on the devices hardware input queue, for virtual devices the processing of the
303Crypto operations is usually completed during the enqueue call to the Crypto
304device. The dequeue burst API will retrieve any processed operations available
305from the queue pair on the Crypto device, from physical devices this is usually
306directly from the devices processed queue, and for virtual device's from a
307``rte_ring`` where processed operations are placed after being processed on the
308enqueue call.
309
310
311Private data
312~~~~~~~~~~~~
313For session-based operations, the set and get API provides a mechanism for an
314application to store and retrieve the private user data information stored along
315with the crypto session.
316
317For example, suppose an application is submitting a crypto operation with a session
318associated and wants to indicate private user data information which is required to be
319used after completion of the crypto operation. In this case, the application can use
320the set API to set the user data and retrieve it using get API.
321
322.. code-block:: c
323
324	int rte_cryptodev_sym_session_set_user_data(
325		struct rte_cryptodev_sym_session *sess,	void *data, uint16_t size);
326
327	void * rte_cryptodev_sym_session_get_user_data(
328		struct rte_cryptodev_sym_session *sess);
329
330Please note the ``size`` passed to set API cannot be bigger than the predefined
331``user_data_sz`` when creating the session header mempool, otherwise the
332function will return error. Also when ``user_data_sz`` was defined as ``0`` when
333creating the session header mempool, the get API will always return ``NULL``.
334
335For session-less mode, the private user data information can be placed along with the
336``struct rte_crypto_op``. The ``rte_crypto_op::private_data_offset`` indicates the
337start of private data information. The offset is counted from the start of the
338rte_crypto_op including other crypto information such as the IVs (since there can
339be an IV also for authentication).
340
341
342Enqueue / Dequeue Burst APIs
343~~~~~~~~~~~~~~~~~~~~~~~~~~~~
344
345The burst enqueue API uses a Crypto device identifier and a queue pair
346identifier to specify the Crypto device queue pair to schedule the processing on.
347The ``nb_ops`` parameter is the number of operations to process which are
348supplied in the ``ops`` array of ``rte_crypto_op`` structures.
349The enqueue function returns the number of operations it actually enqueued for
350processing, a return value equal to ``nb_ops`` means that all packets have been
351enqueued.
352
353.. code-block:: c
354
355   uint16_t rte_cryptodev_enqueue_burst(uint8_t dev_id, uint16_t qp_id,
356                                        struct rte_crypto_op **ops, uint16_t nb_ops)
357
358The dequeue API uses the same format as the enqueue API of processed but
359the ``nb_ops`` and ``ops`` parameters are now used to specify the max processed
360operations the user wishes to retrieve and the location in which to store them.
361The API call returns the actual number of processed operations returned, this
362can never be larger than ``nb_ops``.
363
364.. code-block:: c
365
366   uint16_t rte_cryptodev_dequeue_burst(uint8_t dev_id, uint16_t qp_id,
367                                        struct rte_crypto_op **ops, uint16_t nb_ops)
368
369
370Operation Representation
371~~~~~~~~~~~~~~~~~~~~~~~~
372
373An Crypto operation is represented by an rte_crypto_op structure, which is a
374generic metadata container for all necessary information required for the
375Crypto operation to be processed on a particular Crypto device poll mode driver.
376
377.. figure:: img/crypto_op.*
378
379The operation structure includes the operation type, the operation status
380and the session type (session-based/less), a reference to the operation
381specific data, which can vary in size and content depending on the operation
382being provisioned. It also contains the source mempool for the operation,
383if it allocated from a mempool.
384
385If Crypto operations are allocated from a Crypto operation mempool, see next
386section, there is also the ability to allocate private memory with the
387operation for applications purposes.
388
389Application software is responsible for specifying all the operation specific
390fields in the ``rte_crypto_op`` structure which are then used by the Crypto PMD
391to process the requested operation.
392
393
394Operation Management and Allocation
395~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
396
397The cryptodev library provides an API set for managing Crypto operations which
398utilize the Mempool Library to allocate operation buffers. Therefore, it ensures
399that the crypto operation is interleaved optimally across the channels and
400ranks for optimal processing.
401A ``rte_crypto_op`` contains a field indicating the pool that it originated from.
402When calling ``rte_crypto_op_free(op)``, the operation returns to its original pool.
403
404.. code-block:: c
405
406   extern struct rte_mempool *
407   rte_crypto_op_pool_create(const char *name, enum rte_crypto_op_type type,
408                             unsigned nb_elts, unsigned cache_size, uint16_t priv_size,
409                             int socket_id);
410
411During pool creation ``rte_crypto_op_init()`` is called as a constructor to
412initialize each Crypto operation which subsequently calls
413``__rte_crypto_op_reset()`` to configure any operation type specific fields based
414on the type parameter.
415
416
417``rte_crypto_op_alloc()`` and ``rte_crypto_op_bulk_alloc()`` are used to allocate
418Crypto operations of a specific type from a given Crypto operation mempool.
419``__rte_crypto_op_reset()`` is called on each operation before being returned to
420allocate to a user so the operation is always in a good known state before use
421by the application.
422
423.. code-block:: c
424
425   struct rte_crypto_op *rte_crypto_op_alloc(struct rte_mempool *mempool,
426                                             enum rte_crypto_op_type type)
427
428   unsigned rte_crypto_op_bulk_alloc(struct rte_mempool *mempool,
429                                     enum rte_crypto_op_type type,
430                                     struct rte_crypto_op **ops, uint16_t nb_ops)
431
432``rte_crypto_op_free()`` is called by the application to return an operation to
433its allocating pool.
434
435.. code-block:: c
436
437   void rte_crypto_op_free(struct rte_crypto_op *op)
438
439
440Symmetric Cryptography Support
441------------------------------
442
443The cryptodev library currently provides support for the following symmetric
444Crypto operations; cipher, authentication, including chaining of these
445operations, as well as also supporting AEAD operations.
446
447
448Session and Session Management
449~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
450
451Sessions are used in symmetric cryptographic processing to store the immutable
452data defined in a cryptographic transform which is used in the operation
453processing of a packet flow. Sessions are used to manage information such as
454expand cipher keys and HMAC IPADs and OPADs, which need to be calculated for a
455particular Crypto operation, but are immutable on a packet to packet basis for
456a flow. Crypto sessions cache this immutable data in a optimal way for the
457underlying PMD and this allows further acceleration of the offload of
458Crypto workloads.
459
460.. figure:: img/cryptodev_sym_sess.*
461
462The Crypto device framework provides APIs to create session mempool and allocate
463and initialize sessions for crypto devices, where sessions are mempool objects.
464The application has to use ``rte_cryptodev_sym_session_pool_create()`` to
465create the session header mempool that creates a mempool with proper element
466size automatically and stores necessary information for safely accessing the
467session in the mempool's private data field.
468
469To create a mempool for storing session private data, the application has two
470options. The first is to create another mempool with elt size equal to or
471bigger than the maximum session private data size of all crypto devices that
472will share the same session header. The creation of the mempool shall use the
473traditional ``rte_mempool_create()`` with the correct ``elt_size``. The other
474option is to change the ``elt_size`` parameter in
475``rte_cryptodev_sym_session_pool_create()`` to the correct value. The first
476option is more complex to implement but may result in better memory usage as
477a session header normally takes smaller memory footprint as the session private
478data.
479
480Once the session mempools have been created, ``rte_cryptodev_sym_session_create()``
481is used to allocate an uninitialized session from the given mempool.
482The session then must be initialized using ``rte_cryptodev_sym_session_init()``
483for each of the required crypto devices. A symmetric transform chain
484is used to specify the operation and its parameters. See the section below for
485details on transforms.
486
487When a session is no longer used, user must call ``rte_cryptodev_sym_session_clear()``
488for each of the crypto devices that are using the session, to free all driver
489private session data. Once this is done, session should be freed using
490``rte_cryptodev_sym_session_free`` which returns them to their mempool.
491
492
493Transforms and Transform Chaining
494~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
495
496Symmetric Crypto transforms (``rte_crypto_sym_xform``) are the mechanism used
497to specify the details of the Crypto operation. For chaining of symmetric
498operations such as cipher encrypt and authentication generate, the next pointer
499allows transform to be chained together. Crypto devices which support chaining
500must publish the chaining of symmetric Crypto operations feature flag. Allocation of the
501xform structure is in the application domain. To allow future API extensions in a
502backwardly compatible manner, e.g. addition of a new parameter, the application should
503zero the full xform struct before populating it.
504
505Currently there are three transforms types cipher, authentication and AEAD.
506Also it is important to note that the order in which the
507transforms are passed indicates the order of the chaining.
508
509.. code-block:: c
510
511    struct rte_crypto_sym_xform {
512        struct rte_crypto_sym_xform *next;
513        /**< next xform in chain */
514        enum rte_crypto_sym_xform_type type;
515        /**< xform type */
516        union {
517            struct rte_crypto_auth_xform auth;
518            /**< Authentication / hash xform */
519            struct rte_crypto_cipher_xform cipher;
520            /**< Cipher xform */
521            struct rte_crypto_aead_xform aead;
522            /**< AEAD xform */
523        };
524    };
525
526The API does not place a limit on the number of transforms that can be chained
527together but this will be limited by the underlying Crypto device poll mode
528driver which is processing the operation.
529
530.. figure:: img/crypto_xform_chain.*
531
532
533Symmetric Operations
534~~~~~~~~~~~~~~~~~~~~
535
536The symmetric Crypto operation structure contains all the mutable data relating
537to performing symmetric cryptographic processing on a referenced mbuf data
538buffer. It is used for either cipher, authentication, AEAD and chained
539operations.
540
541As a minimum the symmetric operation must have a source data buffer (``m_src``),
542a valid session (or transform chain if in session-less mode) and the minimum
543authentication/ cipher/ AEAD parameters required depending on the type of operation
544specified in the session or the transform
545chain.
546
547.. code-block:: c
548
549    struct rte_crypto_sym_op {
550        struct rte_mbuf *m_src;
551        struct rte_mbuf *m_dst;
552
553        union {
554            struct rte_cryptodev_sym_session *session;
555            /**< Handle for the initialised session context */
556            struct rte_crypto_sym_xform *xform;
557            /**< Session-less API Crypto operation parameters */
558        };
559
560        union {
561            struct {
562                struct {
563                    uint32_t offset;
564                    uint32_t length;
565                } data; /**< Data offsets and length for AEAD */
566
567                struct {
568                    uint8_t *data;
569                    rte_iova_t phys_addr;
570                } digest; /**< Digest parameters */
571
572                struct {
573                    uint8_t *data;
574                    rte_iova_t phys_addr;
575                } aad;
576                /**< Additional authentication parameters */
577            } aead;
578
579            struct {
580                struct {
581                    struct {
582                        uint32_t offset;
583                        uint32_t length;
584                    } data; /**< Data offsets and length for ciphering */
585                } cipher;
586
587                struct {
588                    struct {
589                        uint32_t offset;
590                        uint32_t length;
591                    } data;
592                    /**< Data offsets and length for authentication */
593
594                    struct {
595                        uint8_t *data;
596                        rte_iova_t phys_addr;
597                    } digest; /**< Digest parameters */
598                } auth;
599            };
600        };
601    };
602
603Synchronous mode
604----------------
605
606Some cryptodevs support synchronous mode alongside with a standard asynchronous
607mode. In that case operations are performed directly when calling
608``rte_cryptodev_sym_cpu_crypto_process`` method instead of enqueuing and
609dequeuing an operation before. This mode of operation allows cryptodevs which
610utilize CPU cryptographic acceleration to have significant performance boost
611comparing to standard asynchronous approach. Cryptodevs supporting synchronous
612mode have ``RTE_CRYPTODEV_FF_SYM_CPU_CRYPTO`` feature flag set.
613
614To perform a synchronous operation a call to
615``rte_cryptodev_sym_cpu_crypto_process`` has to be made with vectorized
616operation descriptor (``struct rte_crypto_sym_vec``) containing:
617
618- ``num`` - number of operations to perform,
619- pointer to an array of size ``num`` containing a scatter-gather list
620  descriptors of performed operations (``struct rte_crypto_sgl``). Each instance
621  of ``struct rte_crypto_sgl`` consists of a number of segments and a pointer to
622  an array of segment descriptors ``struct rte_crypto_vec``;
623- pointers to arrays of size ``num`` containing IV, AAD and digest information,
624- pointer to an array of size ``num`` where status information will be stored
625  for each operation.
626
627Function returns a number of successfully completed operations and sets
628appropriate status number for each operation in the status array provided as
629a call argument. Status different than zero must be treated as error.
630
631For more details, e.g. how to convert an mbuf to an SGL, please refer to an
632example usage in the IPsec library implementation.
633
634Sample code
635-----------
636
637There are various sample applications that show how to use the cryptodev library,
638such as the L2fwd with Crypto sample application (L2fwd-crypto) and
639the IPsec Security Gateway application (ipsec-secgw).
640
641While these applications demonstrate how an application can be created to perform
642generic crypto operation, the required complexity hides the basic steps of
643how to use the cryptodev APIs.
644
645The following sample code shows the basic steps to encrypt several buffers
646with AES-CBC (although performing other crypto operations is similar),
647using one of the crypto PMDs available in DPDK.
648
649.. code-block:: c
650
651    /*
652     * Simple example to encrypt several buffers with AES-CBC using
653     * the Cryptodev APIs.
654     */
655
656    #define MAX_SESSIONS         1024
657    #define NUM_MBUFS            1024
658    #define POOL_CACHE_SIZE      128
659    #define BURST_SIZE           32
660    #define BUFFER_SIZE          1024
661    #define AES_CBC_IV_LENGTH    16
662    #define AES_CBC_KEY_LENGTH   16
663    #define IV_OFFSET            (sizeof(struct rte_crypto_op) + \
664                                 sizeof(struct rte_crypto_sym_op))
665
666    struct rte_mempool *mbuf_pool, *crypto_op_pool;
667    struct rte_mempool *session_pool, *session_priv_pool;
668    unsigned int session_size;
669    int ret;
670
671    /* Initialize EAL. */
672    ret = rte_eal_init(argc, argv);
673    if (ret < 0)
674        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
675
676    uint8_t socket_id = rte_socket_id();
677
678    /* Create the mbuf pool. */
679    mbuf_pool = rte_pktmbuf_pool_create("mbuf_pool",
680                                    NUM_MBUFS,
681                                    POOL_CACHE_SIZE,
682                                    0,
683                                    RTE_MBUF_DEFAULT_BUF_SIZE,
684                                    socket_id);
685    if (mbuf_pool == NULL)
686        rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
687
688    /*
689     * The IV is always placed after the crypto operation,
690     * so some private data is required to be reserved.
691     */
692    unsigned int crypto_op_private_data = AES_CBC_IV_LENGTH;
693
694    /* Create crypto operation pool. */
695    crypto_op_pool = rte_crypto_op_pool_create("crypto_op_pool",
696                                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
697                                            NUM_MBUFS,
698                                            POOL_CACHE_SIZE,
699                                            crypto_op_private_data,
700                                            socket_id);
701    if (crypto_op_pool == NULL)
702        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
703
704    /* Create the virtual crypto device. */
705    char args[128];
706    const char *crypto_name = "crypto_aesni_mb0";
707    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
708    ret = rte_vdev_init(crypto_name, args);
709    if (ret != 0)
710        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
711
712    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
713
714    /* Get private session data size. */
715    session_size = rte_cryptodev_sym_get_private_session_size(cdev_id);
716
717    #ifdef USE_TWO_MEMPOOLS
718    /* Create session mempool for the session header. */
719    session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
720                                    MAX_SESSIONS,
721                                    0,
722                                    POOL_CACHE_SIZE,
723                                    0,
724                                    socket_id);
725
726    /*
727     * Create session private data mempool for the
728     * private session data for the crypto device.
729     */
730    session_priv_pool = rte_mempool_create("session_pool",
731                                    MAX_SESSIONS,
732                                    session_size,
733                                    POOL_CACHE_SIZE,
734                                    0, NULL, NULL, NULL,
735                                    NULL, socket_id,
736                                    0);
737
738    #else
739    /* Use of the same mempool for session header and private data */
740	session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
741                                    MAX_SESSIONS * 2,
742                                    session_size,
743                                    POOL_CACHE_SIZE,
744                                    0,
745                                    socket_id);
746
747	session_priv_pool = session_pool;
748
749    #endif
750
751    /* Configure the crypto device. */
752    struct rte_cryptodev_config conf = {
753        .nb_queue_pairs = 1,
754        .socket_id = socket_id
755    };
756
757    struct rte_cryptodev_qp_conf qp_conf = {
758        .nb_descriptors = 2048,
759        .mp_session = session_pool,
760        .mp_session_private = session_priv_pool
761    };
762
763    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
764        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
765
766    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf, socket_id) < 0)
767        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
768
769    if (rte_cryptodev_start(cdev_id) < 0)
770        rte_exit(EXIT_FAILURE, "Failed to start device\n");
771
772    /* Create the crypto transform. */
773    uint8_t cipher_key[16] = {0};
774    struct rte_crypto_sym_xform cipher_xform = {
775        .next = NULL,
776        .type = RTE_CRYPTO_SYM_XFORM_CIPHER,
777        .cipher = {
778            .op = RTE_CRYPTO_CIPHER_OP_ENCRYPT,
779            .algo = RTE_CRYPTO_CIPHER_AES_CBC,
780            .key = {
781                .data = cipher_key,
782                .length = AES_CBC_KEY_LENGTH
783            },
784            .iv = {
785                .offset = IV_OFFSET,
786                .length = AES_CBC_IV_LENGTH
787            }
788        }
789    };
790
791    /* Create crypto session and initialize it for the crypto device. */
792    struct rte_cryptodev_sym_session *session;
793    session = rte_cryptodev_sym_session_create(session_pool);
794    if (session == NULL)
795        rte_exit(EXIT_FAILURE, "Session could not be created\n");
796
797    if (rte_cryptodev_sym_session_init(cdev_id, session,
798                    &cipher_xform, session_priv_pool) < 0)
799        rte_exit(EXIT_FAILURE, "Session could not be initialized "
800                    "for the crypto device\n");
801
802    /* Get a burst of crypto operations. */
803    struct rte_crypto_op *crypto_ops[BURST_SIZE];
804    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
805                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
806                            crypto_ops, BURST_SIZE) == 0)
807        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
808
809    /* Get a burst of mbufs. */
810    struct rte_mbuf *mbufs[BURST_SIZE];
811    if (rte_pktmbuf_alloc_bulk(mbuf_pool, mbufs, BURST_SIZE) < 0)
812        rte_exit(EXIT_FAILURE, "Not enough mbufs available");
813
814    /* Initialize the mbufs and append them to the crypto operations. */
815    unsigned int i;
816    for (i = 0; i < BURST_SIZE; i++) {
817        if (rte_pktmbuf_append(mbufs[i], BUFFER_SIZE) == NULL)
818            rte_exit(EXIT_FAILURE, "Not enough room in the mbuf\n");
819        crypto_ops[i]->sym->m_src = mbufs[i];
820    }
821
822    /* Set up the crypto operations. */
823    for (i = 0; i < BURST_SIZE; i++) {
824        struct rte_crypto_op *op = crypto_ops[i];
825        /* Modify bytes of the IV at the end of the crypto operation */
826        uint8_t *iv_ptr = rte_crypto_op_ctod_offset(op, uint8_t *,
827                                                IV_OFFSET);
828
829        generate_random_bytes(iv_ptr, AES_CBC_IV_LENGTH);
830
831        op->sym->cipher.data.offset = 0;
832        op->sym->cipher.data.length = BUFFER_SIZE;
833
834        /* Attach the crypto session to the operation */
835        rte_crypto_op_attach_sym_session(op, session);
836    }
837
838    /* Enqueue the crypto operations in the crypto device. */
839    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
840                                            crypto_ops, BURST_SIZE);
841
842    /*
843     * Dequeue the crypto operations until all the operations
844     * are processed in the crypto device.
845     */
846    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
847    do {
848        struct rte_crypto_op *dequeued_ops[BURST_SIZE];
849        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
850                                        dequeued_ops, BURST_SIZE);
851        total_num_dequeued_ops += num_dequeued_ops;
852
853        /* Check if operation was processed successfully */
854        for (i = 0; i < num_dequeued_ops; i++) {
855            if (dequeued_ops[i]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
856                rte_exit(EXIT_FAILURE,
857                        "Some operations were not processed correctly");
858        }
859
860        rte_mempool_put_bulk(crypto_op_pool, (void **)dequeued_ops,
861                                            num_dequeued_ops);
862    } while (total_num_dequeued_ops < num_enqueued_ops);
863
864Asymmetric Cryptography
865-----------------------
866
867The cryptodev library currently provides support for the following asymmetric
868Crypto operations; RSA, Modular exponentiation and inversion, Diffie-Hellman
869public and/or private key generation and shared secret compute, DSA Signature
870generation and verification.
871
872Session and Session Management
873~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
874
875Sessions are used in asymmetric cryptographic processing to store the immutable
876data defined in asymmetric cryptographic transform which is further used in the
877operation processing. Sessions typically stores information, such as, public
878and private key information or domain params or prime modulus data i.e. immutable
879across data sets. Crypto sessions cache this immutable data in a optimal way for the
880underlying PMD and this allows further acceleration of the offload of Crypto workloads.
881
882Like symmetric, the Crypto device framework provides APIs to allocate and initialize
883asymmetric sessions for crypto devices, where sessions are mempool objects.
884It is the application's responsibility to create and manage the session mempools.
885Application using both symmetric and asymmetric sessions should allocate and maintain
886different sessions pools for each type.
887
888An application can use ``rte_cryptodev_get_asym_session_private_size()`` to
889get the private size of asymmetric session on a given crypto device. This
890function would allow an application to calculate the max device asymmetric
891session size of all crypto devices to create a single session mempool.
892If instead an application creates multiple asymmetric session mempools,
893the Crypto device framework also provides ``rte_cryptodev_asym_get_header_session_size()`` to get
894the size of an uninitialized session.
895
896Once the session mempools have been created, ``rte_cryptodev_asym_session_create()``
897is used to allocate an uninitialized asymmetric session from the given mempool.
898The session then must be initialized using ``rte_cryptodev_asym_session_init()``
899for each of the required crypto devices. An asymmetric transform chain
900is used to specify the operation and its parameters. See the section below for
901details on transforms.
902
903When a session is no longer used, user must call ``rte_cryptodev_asym_session_clear()``
904for each of the crypto devices that are using the session, to free all driver
905private asymmetric session data. Once this is done, session should be freed using
906``rte_cryptodev_asym_session_free()`` which returns them to their mempool.
907
908Asymmetric Sessionless Support
909~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
910
911Asymmetric crypto framework supports session-less operations as well.
912
913Fields that should be set by user are:
914
915Member xform of struct rte_crypto_asym_op should point to the user created rte_crypto_asym_xform.
916Note that rte_crypto_asym_xform should be immutable for the lifetime of associated crypto_op.
917
918Member sess_type of rte_crypto_op should also be set to RTE_CRYPTO_OP_SESSIONLESS.
919
920Transforms and Transform Chaining
921~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
922
923Asymmetric Crypto transforms (``rte_crypto_asym_xform``) are the mechanism used
924to specify the details of the asymmetric Crypto operation. Next pointer within
925xform allows transform to be chained together. Also it is important to note that
926the order in which the transforms are passed indicates the order of the chaining. Allocation
927of the xform structure is in the application domain. To allow future API extensions in a
928backwardly compatible manner, e.g. addition of a new parameter, the application should
929zero the full xform struct before populating it.
930
931Not all asymmetric crypto xforms are supported for chaining. Currently supported
932asymmetric crypto chaining is Diffie-Hellman private key generation followed by
933public generation. Also, currently API does not support chaining of symmetric and
934asymmetric crypto xforms.
935
936Each xform defines specific asymmetric crypto algo. Currently supported are:
937* RSA
938* Modular operations (Exponentiation and Inverse)
939* Diffie-Hellman
940* DSA
941* None - special case where PMD may support a passthrough mode. More for diagnostic purpose
942
943See *DPDK API Reference* for details on each rte_crypto_xxx_xform struct
944
945Asymmetric Operations
946~~~~~~~~~~~~~~~~~~~~~
947
948The asymmetric Crypto operation structure contains all the mutable data relating
949to asymmetric cryptographic processing on an input data buffer. It uses either
950RSA, Modular, Diffie-Hellman or DSA operations depending upon session it is attached
951to.
952
953Every operation must carry a valid session handle which further carries information
954on xform or xform-chain to be performed on op. Every xform type defines its own set
955of operational params in their respective rte_crypto_xxx_op_param struct. Depending
956on xform information within session, PMD picks up and process respective op_param
957struct.
958Unlike symmetric, asymmetric operations do not use mbufs for input/output.
959They operate on data buffer of type ``rte_crypto_param``.
960
961See *DPDK API Reference* for details on each rte_crypto_xxx_op_param struct
962
963Asymmetric crypto Sample code
964-----------------------------
965
966There's a unit test application test_cryptodev_asym.c inside unit test framework that
967show how to setup and process asymmetric operations using cryptodev library.
968
969The following sample code shows the basic steps to compute modular exponentiation
970using 1024-bit modulus length using openssl PMD available in DPDK (performing other
971crypto operations is similar except change to respective op and xform setup).
972
973.. code-block:: c
974
975    /*
976     * Simple example to compute modular exponentiation with 1024-bit key
977     *
978     */
979    #define MAX_ASYM_SESSIONS	10
980    #define NUM_ASYM_BUFS	10
981
982    struct rte_mempool *crypto_op_pool, *asym_session_pool;
983    unsigned int asym_session_size;
984    int ret;
985
986    /* Initialize EAL. */
987    ret = rte_eal_init(argc, argv);
988    if (ret < 0)
989        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
990
991    uint8_t socket_id = rte_socket_id();
992
993    /* Create crypto operation pool. */
994    crypto_op_pool = rte_crypto_op_pool_create(
995                                    "crypto_op_pool",
996                                    RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
997                                    NUM_ASYM_BUFS, 0, 0,
998                                    socket_id);
999    if (crypto_op_pool == NULL)
1000        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
1001
1002    /* Create the virtual crypto device. */
1003    char args[128];
1004    const char *crypto_name = "crypto_openssl";
1005    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
1006    ret = rte_vdev_init(crypto_name, args);
1007    if (ret != 0)
1008        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
1009
1010    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
1011
1012    /* Get private asym session data size. */
1013    asym_session_size = rte_cryptodev_get_asym_private_session_size(cdev_id);
1014
1015    /*
1016     * Create session mempool, with two objects per session,
1017     * one for the session header and another one for the
1018     * private asym session data for the crypto device.
1019     */
1020    asym_session_pool = rte_mempool_create("asym_session_pool",
1021                                    MAX_ASYM_SESSIONS * 2,
1022                                    asym_session_size,
1023                                    0,
1024                                    0, NULL, NULL, NULL,
1025                                    NULL, socket_id,
1026                                    0);
1027
1028    /* Configure the crypto device. */
1029    struct rte_cryptodev_config conf = {
1030        .nb_queue_pairs = 1,
1031        .socket_id = socket_id
1032    };
1033    struct rte_cryptodev_qp_conf qp_conf = {
1034        .nb_descriptors = 2048
1035    };
1036
1037    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
1038        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
1039
1040    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf,
1041                            socket_id, asym_session_pool) < 0)
1042        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
1043
1044    if (rte_cryptodev_start(cdev_id) < 0)
1045        rte_exit(EXIT_FAILURE, "Failed to start device\n");
1046
1047    /* Setup crypto xform to do modular exponentiation with 1024 bit
1048	 * length modulus
1049	 */
1050    struct rte_crypto_asym_xform modex_xform = {
1051		.next = NULL,
1052		.xform_type = RTE_CRYPTO_ASYM_XFORM_MODEX,
1053		.modex = {
1054			.modulus = {
1055				.data =
1056				(uint8_t *)
1057				("\xb3\xa1\xaf\xb7\x13\x08\x00\x0a\x35\xdc\x2b\x20\x8d"
1058				"\xa1\xb5\xce\x47\x8a\xc3\x80\xf4\x7d\x4a\xa2\x62\xfd\x61\x7f"
1059				"\xb5\xa8\xde\x0a\x17\x97\xa0\xbf\xdf\x56\x5a\x3d\x51\x56\x4f"
1060				"\x70\x70\x3f\x63\x6a\x44\x5b\xad\x84\x0d\x3f\x27\x6e\x3b\x34"
1061				"\x91\x60\x14\xb9\xaa\x72\xfd\xa3\x64\xd2\x03\xa7\x53\x87\x9e"
1062				"\x88\x0b\xc1\x14\x93\x1a\x62\xff\xb1\x5d\x74\xcd\x59\x63\x18"
1063				"\x11\x3d\x4f\xba\x75\xd4\x33\x4e\x23\x6b\x7b\x57\x44\xe1\xd3"
1064				"\x03\x13\xa6\xf0\x8b\x60\xb0\x9e\xee\x75\x08\x9d\x71\x63\x13"
1065				"\xcb\xa6\x81\x92\x14\x03\x22\x2d\xde\x55"),
1066				.length = 128
1067			},
1068			.exponent = {
1069				.data = (uint8_t *)("\x01\x00\x01"),
1070				.length = 3
1071			}
1072		}
1073    };
1074    /* Create asym crypto session and initialize it for the crypto device. */
1075    struct rte_cryptodev_asym_session *asym_session;
1076    asym_session = rte_cryptodev_asym_session_create(asym_session_pool);
1077    if (asym_session == NULL)
1078        rte_exit(EXIT_FAILURE, "Session could not be created\n");
1079
1080    if (rte_cryptodev_asym_session_init(cdev_id, asym_session,
1081                    &modex_xform, asym_session_pool) < 0)
1082        rte_exit(EXIT_FAILURE, "Session could not be initialized "
1083                    "for the crypto device\n");
1084
1085    /* Get a burst of crypto operations. */
1086    struct rte_crypto_op *crypto_ops[1];
1087    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
1088                            RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
1089                            crypto_ops, 1) == 0)
1090        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
1091
1092    /* Set up the crypto operations. */
1093    struct rte_crypto_asym_op *asym_op = crypto_ops[0]->asym;
1094
1095	/* calculate mod exp of value 0xf8 */
1096    static unsigned char base[] = {0xF8};
1097    asym_op->modex.base.data = base;
1098    asym_op->modex.base.length = sizeof(base);
1099	asym_op->modex.base.iova = base;
1100
1101    /* Attach the asym crypto session to the operation */
1102    rte_crypto_op_attach_asym_session(op, asym_session);
1103
1104    /* Enqueue the crypto operations in the crypto device. */
1105    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
1106                                            crypto_ops, 1);
1107
1108    /*
1109     * Dequeue the crypto operations until all the operations
1110     * are processed in the crypto device.
1111     */
1112    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
1113    do {
1114        struct rte_crypto_op *dequeued_ops[1];
1115        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
1116                                        dequeued_ops, 1);
1117        total_num_dequeued_ops += num_dequeued_ops;
1118
1119        /* Check if operation was processed successfully */
1120        if (dequeued_ops[0]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
1121                rte_exit(EXIT_FAILURE,
1122                        "Some operations were not processed correctly");
1123
1124    } while (total_num_dequeued_ops < num_enqueued_ops);
1125
1126
1127Asymmetric Crypto Device API
1128~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1129
1130The cryptodev Library API is described in the
1131`DPDK API Reference <https://doc.dpdk.org/api/>`_
1132