xref: /dpdk/doc/guides/prog_guide/cryptodev_lib.rst (revision 6b1a74ef805fd48486e2af6d7ca2439adff484c3)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2016-2017 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.
501
502Currently there are three transforms types cipher, authentication and AEAD.
503Also it is important to note that the order in which the
504transforms are passed indicates the order of the chaining.
505
506.. code-block:: c
507
508    struct rte_crypto_sym_xform {
509        struct rte_crypto_sym_xform *next;
510        /**< next xform in chain */
511        enum rte_crypto_sym_xform_type type;
512        /**< xform type */
513        union {
514            struct rte_crypto_auth_xform auth;
515            /**< Authentication / hash xform */
516            struct rte_crypto_cipher_xform cipher;
517            /**< Cipher xform */
518            struct rte_crypto_aead_xform aead;
519            /**< AEAD xform */
520        };
521    };
522
523The API does not place a limit on the number of transforms that can be chained
524together but this will be limited by the underlying Crypto device poll mode
525driver which is processing the operation.
526
527.. figure:: img/crypto_xform_chain.*
528
529
530Symmetric Operations
531~~~~~~~~~~~~~~~~~~~~
532
533The symmetric Crypto operation structure contains all the mutable data relating
534to performing symmetric cryptographic processing on a referenced mbuf data
535buffer. It is used for either cipher, authentication, AEAD and chained
536operations.
537
538As a minimum the symmetric operation must have a source data buffer (``m_src``),
539a valid session (or transform chain if in session-less mode) and the minimum
540authentication/ cipher/ AEAD parameters required depending on the type of operation
541specified in the session or the transform
542chain.
543
544.. code-block:: c
545
546    struct rte_crypto_sym_op {
547        struct rte_mbuf *m_src;
548        struct rte_mbuf *m_dst;
549
550        union {
551            struct rte_cryptodev_sym_session *session;
552            /**< Handle for the initialised session context */
553            struct rte_crypto_sym_xform *xform;
554            /**< Session-less API Crypto operation parameters */
555        };
556
557        union {
558            struct {
559                struct {
560                    uint32_t offset;
561                    uint32_t length;
562                } data; /**< Data offsets and length for AEAD */
563
564                struct {
565                    uint8_t *data;
566                    rte_iova_t phys_addr;
567                } digest; /**< Digest parameters */
568
569                struct {
570                    uint8_t *data;
571                    rte_iova_t phys_addr;
572                } aad;
573                /**< Additional authentication parameters */
574            } aead;
575
576            struct {
577                struct {
578                    struct {
579                        uint32_t offset;
580                        uint32_t length;
581                    } data; /**< Data offsets and length for ciphering */
582                } cipher;
583
584                struct {
585                    struct {
586                        uint32_t offset;
587                        uint32_t length;
588                    } data;
589                    /**< Data offsets and length for authentication */
590
591                    struct {
592                        uint8_t *data;
593                        rte_iova_t phys_addr;
594                    } digest; /**< Digest parameters */
595                } auth;
596            };
597        };
598    };
599
600Sample code
601-----------
602
603There are various sample applications that show how to use the cryptodev library,
604such as the L2fwd with Crypto sample application (L2fwd-crypto) and
605the IPsec Security Gateway application (ipsec-secgw).
606
607While these applications demonstrate how an application can be created to perform
608generic crypto operation, the required complexity hides the basic steps of
609how to use the cryptodev APIs.
610
611The following sample code shows the basic steps to encrypt several buffers
612with AES-CBC (although performing other crypto operations is similar),
613using one of the crypto PMDs available in DPDK.
614
615.. code-block:: c
616
617    /*
618     * Simple example to encrypt several buffers with AES-CBC using
619     * the Cryptodev APIs.
620     */
621
622    #define MAX_SESSIONS         1024
623    #define NUM_MBUFS            1024
624    #define POOL_CACHE_SIZE      128
625    #define BURST_SIZE           32
626    #define BUFFER_SIZE          1024
627    #define AES_CBC_IV_LENGTH    16
628    #define AES_CBC_KEY_LENGTH   16
629    #define IV_OFFSET            (sizeof(struct rte_crypto_op) + \
630                                 sizeof(struct rte_crypto_sym_op))
631
632    struct rte_mempool *mbuf_pool, *crypto_op_pool;
633    struct rte_mempool *session_pool, *session_priv_pool;
634    unsigned int session_size;
635    int ret;
636
637    /* Initialize EAL. */
638    ret = rte_eal_init(argc, argv);
639    if (ret < 0)
640        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
641
642    uint8_t socket_id = rte_socket_id();
643
644    /* Create the mbuf pool. */
645    mbuf_pool = rte_pktmbuf_pool_create("mbuf_pool",
646                                    NUM_MBUFS,
647                                    POOL_CACHE_SIZE,
648                                    0,
649                                    RTE_MBUF_DEFAULT_BUF_SIZE,
650                                    socket_id);
651    if (mbuf_pool == NULL)
652        rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
653
654    /*
655     * The IV is always placed after the crypto operation,
656     * so some private data is required to be reserved.
657     */
658    unsigned int crypto_op_private_data = AES_CBC_IV_LENGTH;
659
660    /* Create crypto operation pool. */
661    crypto_op_pool = rte_crypto_op_pool_create("crypto_op_pool",
662                                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
663                                            NUM_MBUFS,
664                                            POOL_CACHE_SIZE,
665                                            crypto_op_private_data,
666                                            socket_id);
667    if (crypto_op_pool == NULL)
668        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
669
670    /* Create the virtual crypto device. */
671    char args[128];
672    const char *crypto_name = "crypto_aesni_mb0";
673    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
674    ret = rte_vdev_init(crypto_name, args);
675    if (ret != 0)
676        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
677
678    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
679
680    /* Get private session data size. */
681    session_size = rte_cryptodev_sym_get_private_session_size(cdev_id);
682
683    #ifdef USE_TWO_MEMPOOLS
684    /* Create session mempool for the session header. */
685    session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
686                                    MAX_SESSIONS,
687                                    0,
688                                    POOL_CACHE_SIZE,
689                                    0,
690                                    socket_id);
691
692    /*
693     * Create session private data mempool for the
694     * private session data for the crypto device.
695     */
696    session_priv_pool = rte_mempool_create("session_pool",
697                                    MAX_SESSIONS,
698                                    session_size,
699                                    POOL_CACHE_SIZE,
700                                    0, NULL, NULL, NULL,
701                                    NULL, socket_id,
702                                    0);
703
704    #else
705    /* Use of the same mempool for session header and private data */
706	session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
707                                    MAX_SESSIONS * 2,
708                                    session_size,
709                                    POOL_CACHE_SIZE,
710                                    0,
711                                    socket_id);
712
713	session_priv_pool = session_pool;
714
715    #endif
716
717    /* Configure the crypto device. */
718    struct rte_cryptodev_config conf = {
719        .nb_queue_pairs = 1,
720        .socket_id = socket_id
721    };
722
723    struct rte_cryptodev_qp_conf qp_conf = {
724        .nb_descriptors = 2048,
725        .mp_session = session_pool,
726        .mp_session_private = session_priv_pool
727    };
728
729    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
730        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
731
732    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf, socket_id) < 0)
733        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
734
735    if (rte_cryptodev_start(cdev_id) < 0)
736        rte_exit(EXIT_FAILURE, "Failed to start device\n");
737
738    /* Create the crypto transform. */
739    uint8_t cipher_key[16] = {0};
740    struct rte_crypto_sym_xform cipher_xform = {
741        .next = NULL,
742        .type = RTE_CRYPTO_SYM_XFORM_CIPHER,
743        .cipher = {
744            .op = RTE_CRYPTO_CIPHER_OP_ENCRYPT,
745            .algo = RTE_CRYPTO_CIPHER_AES_CBC,
746            .key = {
747                .data = cipher_key,
748                .length = AES_CBC_KEY_LENGTH
749            },
750            .iv = {
751                .offset = IV_OFFSET,
752                .length = AES_CBC_IV_LENGTH
753            }
754        }
755    };
756
757    /* Create crypto session and initialize it for the crypto device. */
758    struct rte_cryptodev_sym_session *session;
759    session = rte_cryptodev_sym_session_create(session_pool);
760    if (session == NULL)
761        rte_exit(EXIT_FAILURE, "Session could not be created\n");
762
763    if (rte_cryptodev_sym_session_init(cdev_id, session,
764                    &cipher_xform, session_priv_pool) < 0)
765        rte_exit(EXIT_FAILURE, "Session could not be initialized "
766                    "for the crypto device\n");
767
768    /* Get a burst of crypto operations. */
769    struct rte_crypto_op *crypto_ops[BURST_SIZE];
770    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
771                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
772                            crypto_ops, BURST_SIZE) == 0)
773        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
774
775    /* Get a burst of mbufs. */
776    struct rte_mbuf *mbufs[BURST_SIZE];
777    if (rte_pktmbuf_alloc_bulk(mbuf_pool, mbufs, BURST_SIZE) < 0)
778        rte_exit(EXIT_FAILURE, "Not enough mbufs available");
779
780    /* Initialize the mbufs and append them to the crypto operations. */
781    unsigned int i;
782    for (i = 0; i < BURST_SIZE; i++) {
783        if (rte_pktmbuf_append(mbufs[i], BUFFER_SIZE) == NULL)
784            rte_exit(EXIT_FAILURE, "Not enough room in the mbuf\n");
785        crypto_ops[i]->sym->m_src = mbufs[i];
786    }
787
788    /* Set up the crypto operations. */
789    for (i = 0; i < BURST_SIZE; i++) {
790        struct rte_crypto_op *op = crypto_ops[i];
791        /* Modify bytes of the IV at the end of the crypto operation */
792        uint8_t *iv_ptr = rte_crypto_op_ctod_offset(op, uint8_t *,
793                                                IV_OFFSET);
794
795        generate_random_bytes(iv_ptr, AES_CBC_IV_LENGTH);
796
797        op->sym->cipher.data.offset = 0;
798        op->sym->cipher.data.length = BUFFER_SIZE;
799
800        /* Attach the crypto session to the operation */
801        rte_crypto_op_attach_sym_session(op, session);
802    }
803
804    /* Enqueue the crypto operations in the crypto device. */
805    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
806                                            crypto_ops, BURST_SIZE);
807
808    /*
809     * Dequeue the crypto operations until all the operations
810     * are processed in the crypto device.
811     */
812    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
813    do {
814        struct rte_crypto_op *dequeued_ops[BURST_SIZE];
815        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
816                                        dequeued_ops, BURST_SIZE);
817        total_num_dequeued_ops += num_dequeued_ops;
818
819        /* Check if operation was processed successfully */
820        for (i = 0; i < num_dequeued_ops; i++) {
821            if (dequeued_ops[i]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
822                rte_exit(EXIT_FAILURE,
823                        "Some operations were not processed correctly");
824        }
825
826        rte_mempool_put_bulk(crypto_op_pool, (void **)dequeued_ops,
827                                            num_dequeued_ops);
828    } while (total_num_dequeued_ops < num_enqueued_ops);
829
830Asymmetric Cryptography
831-----------------------
832
833The cryptodev library currently provides support for the following asymmetric
834Crypto operations; RSA, Modular exponentiation and inversion, Diffie-Hellman
835public and/or private key generation and shared secret compute, DSA Signature
836generation and verification.
837
838Session and Session Management
839~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
840
841Sessions are used in asymmetric cryptographic processing to store the immutable
842data defined in asymmetric cryptographic transform which is further used in the
843operation processing. Sessions typically stores information, such as, public
844and private key information or domain params or prime modulus data i.e. immutable
845across data sets. Crypto sessions cache this immutable data in a optimal way for the
846underlying PMD and this allows further acceleration of the offload of Crypto workloads.
847
848Like symmetric, the Crypto device framework provides APIs to allocate and initialize
849asymmetric sessions for crypto devices, where sessions are mempool objects.
850It is the application's responsibility to create and manage the session mempools.
851Application using both symmetric and asymmetric sessions should allocate and maintain
852different sessions pools for each type.
853
854An application can use ``rte_cryptodev_get_asym_session_private_size()`` to
855get the private size of asymmetric session on a given crypto device. This
856function would allow an application to calculate the max device asymmetric
857session size of all crypto devices to create a single session mempool.
858If instead an application creates multiple asymmetric session mempools,
859the Crypto device framework also provides ``rte_cryptodev_asym_get_header_session_size()`` to get
860the size of an uninitialized session.
861
862Once the session mempools have been created, ``rte_cryptodev_asym_session_create()``
863is used to allocate an uninitialized asymmetric session from the given mempool.
864The session then must be initialized using ``rte_cryptodev_asym_session_init()``
865for each of the required crypto devices. An asymmetric transform chain
866is used to specify the operation and its parameters. See the section below for
867details on transforms.
868
869When a session is no longer used, user must call ``rte_cryptodev_asym_session_clear()``
870for each of the crypto devices that are using the session, to free all driver
871private asymmetric session data. Once this is done, session should be freed using
872``rte_cryptodev_asym_session_free()`` which returns them to their mempool.
873
874Asymmetric Sessionless Support
875~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
876Currently asymmetric crypto framework does not support sessionless.
877
878Transforms and Transform Chaining
879~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
880
881Asymmetric Crypto transforms (``rte_crypto_asym_xform``) are the mechanism used
882to specify the details of the asymmetric Crypto operation. Next pointer within
883xform allows transform to be chained together. Also it is important to note that
884the order in which the transforms are passed indicates the order of the chaining.
885
886Not all asymmetric crypto xforms are supported for chaining. Currently supported
887asymmetric crypto chaining is Diffie-Hellman private key generation followed by
888public generation. Also, currently API does not support chaining of symmetric and
889asymmetric crypto xforms.
890
891Each xform defines specific asymmetric crypto algo. Currently supported are:
892* RSA
893* Modular operations (Exponentiation and Inverse)
894* Diffie-Hellman
895* DSA
896* None - special case where PMD may support a passthrough mode. More for diagnostic purpose
897
898See *DPDK API Reference* for details on each rte_crypto_xxx_xform struct
899
900Asymmetric Operations
901~~~~~~~~~~~~~~~~~~~~~
902
903The asymmetric Crypto operation structure contains all the mutable data relating
904to asymmetric cryptographic processing on an input data buffer. It uses either
905RSA, Modular, Diffie-Hellman or DSA operations depending upon session it is attached
906to.
907
908Every operation must carry a valid session handle which further carries information
909on xform or xform-chain to be performed on op. Every xform type defines its own set
910of operational params in their respective rte_crypto_xxx_op_param struct. Depending
911on xform information within session, PMD picks up and process respective op_param
912struct.
913Unlike symmetric, asymmetric operations do not use mbufs for input/output.
914They operate on data buffer of type ``rte_crypto_param``.
915
916See *DPDK API Reference* for details on each rte_crypto_xxx_op_param struct
917
918Asymmetric crypto Sample code
919-----------------------------
920
921There's a unit test application test_cryptodev_asym.c inside unit test framework that
922show how to setup and process asymmetric operations using cryptodev library.
923
924The following sample code shows the basic steps to compute modular exponentiation
925using 1024-bit modulus length using openssl PMD available in DPDK (performing other
926crypto operations is similar except change to respective op and xform setup).
927
928.. code-block:: c
929
930    /*
931     * Simple example to compute modular exponentiation with 1024-bit key
932     *
933     */
934    #define MAX_ASYM_SESSIONS	10
935    #define NUM_ASYM_BUFS	10
936
937    struct rte_mempool *crypto_op_pool, *asym_session_pool;
938    unsigned int asym_session_size;
939    int ret;
940
941    /* Initialize EAL. */
942    ret = rte_eal_init(argc, argv);
943    if (ret < 0)
944        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
945
946    uint8_t socket_id = rte_socket_id();
947
948    /* Create crypto operation pool. */
949    crypto_op_pool = rte_crypto_op_pool_create(
950                                    "crypto_op_pool",
951                                    RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
952                                    NUM_ASYM_BUFS, 0, 0,
953                                    socket_id);
954    if (crypto_op_pool == NULL)
955        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
956
957    /* Create the virtual crypto device. */
958    char args[128];
959    const char *crypto_name = "crypto_openssl";
960    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
961    ret = rte_vdev_init(crypto_name, args);
962    if (ret != 0)
963        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
964
965    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
966
967    /* Get private asym session data size. */
968    asym_session_size = rte_cryptodev_get_asym_private_session_size(cdev_id);
969
970    /*
971     * Create session mempool, with two objects per session,
972     * one for the session header and another one for the
973     * private asym session data for the crypto device.
974     */
975    asym_session_pool = rte_mempool_create("asym_session_pool",
976                                    MAX_ASYM_SESSIONS * 2,
977                                    asym_session_size,
978                                    0,
979                                    0, NULL, NULL, NULL,
980                                    NULL, socket_id,
981                                    0);
982
983    /* Configure the crypto device. */
984    struct rte_cryptodev_config conf = {
985        .nb_queue_pairs = 1,
986        .socket_id = socket_id
987    };
988    struct rte_cryptodev_qp_conf qp_conf = {
989        .nb_descriptors = 2048
990    };
991
992    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
993        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
994
995    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf,
996                            socket_id, asym_session_pool) < 0)
997        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
998
999    if (rte_cryptodev_start(cdev_id) < 0)
1000        rte_exit(EXIT_FAILURE, "Failed to start device\n");
1001
1002    /* Setup crypto xform to do modular exponentiation with 1024 bit
1003	 * length modulus
1004	 */
1005    struct rte_crypto_asym_xform modex_xform = {
1006		.next = NULL,
1007		.xform_type = RTE_CRYPTO_ASYM_XFORM_MODEX,
1008		.modex = {
1009			.modulus = {
1010				.data =
1011				(uint8_t *)
1012				("\xb3\xa1\xaf\xb7\x13\x08\x00\x0a\x35\xdc\x2b\x20\x8d"
1013				"\xa1\xb5\xce\x47\x8a\xc3\x80\xf4\x7d\x4a\xa2\x62\xfd\x61\x7f"
1014				"\xb5\xa8\xde\x0a\x17\x97\xa0\xbf\xdf\x56\x5a\x3d\x51\x56\x4f"
1015				"\x70\x70\x3f\x63\x6a\x44\x5b\xad\x84\x0d\x3f\x27\x6e\x3b\x34"
1016				"\x91\x60\x14\xb9\xaa\x72\xfd\xa3\x64\xd2\x03\xa7\x53\x87\x9e"
1017				"\x88\x0b\xc1\x14\x93\x1a\x62\xff\xb1\x5d\x74\xcd\x59\x63\x18"
1018				"\x11\x3d\x4f\xba\x75\xd4\x33\x4e\x23\x6b\x7b\x57\x44\xe1\xd3"
1019				"\x03\x13\xa6\xf0\x8b\x60\xb0\x9e\xee\x75\x08\x9d\x71\x63\x13"
1020				"\xcb\xa6\x81\x92\x14\x03\x22\x2d\xde\x55"),
1021				.length = 128
1022			},
1023			.exponent = {
1024				.data = (uint8_t *)("\x01\x00\x01"),
1025				.length = 3
1026			}
1027		}
1028    };
1029    /* Create asym crypto session and initialize it for the crypto device. */
1030    struct rte_cryptodev_asym_session *asym_session;
1031    asym_session = rte_cryptodev_asym_session_create(asym_session_pool);
1032    if (asym_session == NULL)
1033        rte_exit(EXIT_FAILURE, "Session could not be created\n");
1034
1035    if (rte_cryptodev_asym_session_init(cdev_id, asym_session,
1036                    &modex_xform, asym_session_pool) < 0)
1037        rte_exit(EXIT_FAILURE, "Session could not be initialized "
1038                    "for the crypto device\n");
1039
1040    /* Get a burst of crypto operations. */
1041    struct rte_crypto_op *crypto_ops[1];
1042    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
1043                            RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
1044                            crypto_ops, 1) == 0)
1045        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
1046
1047    /* Set up the crypto operations. */
1048    struct rte_crypto_asym_op *asym_op = crypto_ops[0]->asym;
1049
1050	/* calculate mod exp of value 0xf8 */
1051    static unsigned char base[] = {0xF8};
1052    asym_op->modex.base.data = base;
1053    asym_op->modex.base.length = sizeof(base);
1054	asym_op->modex.base.iova = base;
1055
1056    /* Attach the asym crypto session to the operation */
1057    rte_crypto_op_attach_asym_session(op, asym_session);
1058
1059    /* Enqueue the crypto operations in the crypto device. */
1060    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
1061                                            crypto_ops, 1);
1062
1063    /*
1064     * Dequeue the crypto operations until all the operations
1065     * are processed in the crypto device.
1066     */
1067    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
1068    do {
1069        struct rte_crypto_op *dequeued_ops[1];
1070        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
1071                                        dequeued_ops, 1);
1072        total_num_dequeued_ops += num_dequeued_ops;
1073
1074        /* Check if operation was processed successfully */
1075        if (dequeued_ops[0]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
1076                rte_exit(EXIT_FAILURE,
1077                        "Some operations were not processed correctly");
1078
1079    } while (total_num_dequeued_ops < num_enqueued_ops);
1080
1081
1082Asymmetric Crypto Device API
1083~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1084
1085The cryptodev Library API is described in the
1086`DPDK API Reference <http://doc.dpdk.org/api/>`_
1087