xref: /dpdk/doc/guides/sample_app_ug/l2_forward_crypto.rst (revision a3a2e2c8f7de433e10b1548df65b20bf10086d9c)
1..  BSD LICENSE
2    Copyright(c) 2016-2017 Intel Corporation. All rights reserved.
3    All rights reserved.
4
5    Redistribution and use in source and binary forms, with or without
6    modification, are permitted provided that the following conditions
7    are met:
8
9    * Redistributions of source code must retain the above copyright
10    notice, this list of conditions and the following disclaimer.
11    * Redistributions in binary form must reproduce the above copyright
12    notice, this list of conditions and the following disclaimer in
13    the documentation and/or other materials provided with the
14    distribution.
15    * Neither the name of Intel Corporation nor the names of its
16    contributors may be used to endorse or promote products derived
17    from this software without specific prior written permission.
18
19    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31.. _l2_fwd_crypto_app:
32
33L2 Forwarding with Crypto Sample Application
34============================================
35
36The L2 Forwarding with Crypto (l2fwd-crypto) sample application is a simple example of packet processing using
37the Data Plane Development Kit (DPDK), in conjunction with the Cryptodev library.
38
39Overview
40--------
41
42The L2 Forwarding with Crypto sample application performs a crypto operation (cipher/hash)
43specified by the user from command line (or using the default values),
44with a crypto device capable of doing that operation,
45for each packet that is received on a RX_PORT and performs L2 forwarding.
46The destination port is the adjacent port from the enabled portmask, that is,
47if the first four ports are enabled (portmask 0xf),
48ports 0 and 1 forward into each other, and ports 2 and 3 forward into each other.
49Also, the MAC addresses are affected as follows:
50
51*   The source MAC address is replaced by the TX_PORT MAC address
52
53*   The destination MAC address is replaced by  02:00:00:00:00:TX_PORT_ID
54
55Compiling the Application
56-------------------------
57
58#.  Go to the example directory:
59
60    .. code-block:: console
61
62        export RTE_SDK=/path/to/rte_sdk
63        cd ${RTE_SDK}/examples/l2fwd-crypto
64
65#.  Set the target (a default target is used if not specified). For example:
66
67    .. code-block:: console
68
69        export RTE_TARGET=x86_64-native-linuxapp-gcc
70
71    *See the DPDK Getting Started Guide* for possible RTE_TARGET values.
72
73#.  Build the application:
74
75    .. code-block:: console
76
77        make
78
79Running the Application
80-----------------------
81
82The application requires a number of command line options:
83
84.. code-block:: console
85
86    ./build/l2fwd-crypto [EAL options] -- [-p PORTMASK] [-q NQ] [-s] [-T PERIOD] /
87    [--cdev_type HW/SW/ANY] [--chain HASH_CIPHER/CIPHER_HASH/CIPHER_ONLY/HASH_ONLY] /
88    [--cipher_algo ALGO] [--cipher_op ENCRYPT/DECRYPT] [--cipher_key KEY] /
89    [--cipher_key_random_size SIZE] [--iv IV] [--iv_random_size SIZE] /
90    [--auth_algo ALGO] [--auth_op GENERATE/VERIFY] [--auth_key KEY] /
91    [--auth_key_random_size SIZE] [--aad AAD] [--aad_random_size SIZE] /
92    [--digest size SIZE] [--sessionless] [--cryptodev_mask MASK]
93
94where,
95
96*   p PORTMASK: A hexadecimal bitmask of the ports to configure (default is all the ports)
97
98*   q NQ: A number of queues (=ports) per lcore (default is 1)
99
100*   s: manage all ports from single core
101
102*   T PERIOD: statistics will be refreshed each PERIOD seconds
103
104    (0 to disable, 10 default, 86400 maximum)
105
106*   cdev_type: select preferred crypto device type: HW, SW or anything (ANY)
107
108    (default is ANY)
109
110*   chain: select the operation chaining to perform: Cipher->Hash (CIPHER_HASH),
111
112    Hash->Cipher (HASH_CIPHER), Cipher (CIPHER_ONLY), Hash(HASH_ONLY)
113
114    (default is Cipher->Hash)
115
116*   cipher_algo: select the ciphering algorithm (default is aes-cbc)
117
118*   cipher_op: select the ciphering operation to perform: ENCRYPT or DECRYPT
119
120    (default is ENCRYPT)
121
122*   cipher_key: set the ciphering key to be used. Bytes has to be separated with ":"
123
124*   cipher_key_random_size: set the size of the ciphering key,
125
126    which will be generated randomly.
127
128    Note that if --cipher_key is used, this will be ignored.
129
130*   iv: set the IV to be used. Bytes has to be separated with ":"
131
132*   iv_random_size: set the size of the IV, which will be generated randomly.
133
134    Note that if --iv is used, this will be ignored.
135
136*   auth_algo: select the authentication algorithm (default is sha1-hmac)
137
138*   auth_op: select the authentication operation to perform: GENERATE or VERIFY
139
140    (default is GENERATE)
141
142*   auth_key: set the authentication key to be used. Bytes has to be separated with ":"
143
144*   auth_key_random_size: set the size of the authentication key,
145
146    which will be generated randomly.
147
148    Note that if --auth_key is used, this will be ignored.
149
150*   aad: set the AAD to be used. Bytes has to be separated with ":"
151
152*   aad_random_size: set the size of the AAD, which will be generated randomly.
153
154    Note that if --aad is used, this will be ignored.
155
156*   digest_size: set the size of the digest to be generated/verified.
157
158*   sessionless: no crypto session will be created.
159
160*   cryptodev_mask: A hexadecimal bitmask of the cryptodevs to be used by the
161    application.
162
163    (default is all cryptodevs).
164
165
166The application requires that crypto devices capable of performing
167the specified crypto operation are available on application initialization.
168This means that HW crypto device/s must be bound to a DPDK driver or
169a SW crypto device/s (virtual crypto PMD) must be created (using --vdev).
170
171To run the application in linuxapp environment with 2 lcores, 2 ports and 2 crypto devices, issue the command:
172
173.. code-block:: console
174
175    $ ./build/l2fwd-crypto -l 0-1 -n 4 --vdev "cryptodev_aesni_mb_pmd" \
176    --vdev "cryptodev_aesni_mb_pmd" -- -p 0x3 --chain CIPHER_HASH \
177    --cipher_op ENCRYPT --cipher_algo aes-cbc \
178    --cipher_key 00:01:02:03:04:05:06:07:08:09:0a:0b:0c:0d:0e:0f \
179    --auth_op GENERATE --auth_algo aes-xcbc-mac \
180    --auth_key 10:11:12:13:14:15:16:17:18:19:1a:1b:1c:1d:1e:1f
181
182Refer to the *DPDK Getting Started Guide* for general information on running applications
183and the Environment Abstraction Layer (EAL) options.
184
185Explanation
186-----------
187
188The L2 forward with Crypto application demonstrates the performance of a crypto operation
189on a packet received on a RX PORT before forwarding it to a TX PORT.
190
191The following figure illustrates a sample flow of a packet in the application,
192from reception until transmission.
193
194.. _figure_l2_fwd_encrypt_flow:
195
196.. figure:: img/l2_fwd_encrypt_flow.*
197
198   Encryption flow Through the L2 Forwarding with Crypto Application
199
200
201The following sections provide some explanation of the application.
202
203Crypto operation specification
204~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
205
206All the packets received in all the ports get transformed by the crypto device/s
207(ciphering and/or authentication).
208The crypto operation to be performed on the packet is parsed from the command line
209(go to "Running the Application section for all the options).
210
211If no parameter is passed, the default crypto operation is:
212
213* Encryption with AES-CBC with 128 bit key.
214
215* Authentication with SHA1-HMAC (generation).
216
217* Keys, IV and AAD are generated randomly.
218
219There are two methods to pass keys, IV and ADD from the command line:
220
221* Passing the full key, separated bytes by ":"::
222
223   --cipher_key 00:11:22:33:44
224
225* Passing the size, so key is generated randomly::
226
227   --cipher_key_random_size 16
228
229**Note**:
230   If full key is passed (first method) and the size is passed as well (second method),
231   the latter will be ignored.
232
233Size of these keys are checked (regardless the method), before starting the app,
234to make sure that it is supported by the crypto devices.
235
236Crypto device initialization
237~~~~~~~~~~~~~~~~~~~~~~~~~~~~
238
239Once the encryption operation is defined, crypto devices are initialized.
240The crypto devices must be either bound to a DPDK driver (if they are physical devices)
241or created using the EAL option --vdev (if they are virtual devices),
242when running the application.
243
244The initialize_cryptodevs() function performs the device initialization.
245It iterates through the list of the available crypto devices and
246check which ones are capable of performing the operation.
247Each device has a set of capabilities associated with it,
248which are stored in the device info structure, so the function checks if the operation
249is within the structure of each device.
250
251The following code checks if the device supports the specified cipher algorithm
252(similar for the authentication algorithm):
253
254.. code-block:: c
255
256   /* Check if device supports cipher algo */
257   i = 0;
258   opt_cipher_algo = options->cipher_xform.cipher.algo;
259   cap = &dev_info.capabilities[i];
260   while (cap->op != RTE_CRYPTO_OP_TYPE_UNDEFINED) {
261           cap_cipher_algo = cap->sym.cipher.algo;
262           if (cap->sym.xform_type ==
263                           RTE_CRYPTO_SYM_XFORM_CIPHER) {
264                   if (cap_cipher_algo == opt_cipher_algo) {
265                           if (check_type(options, &dev_info) == 0)
266                                   break;
267                   }
268           }
269           cap = &dev_info.capabilities[++i];
270   }
271
272If a capable crypto device is found, key sizes are checked to see if they are supported
273(cipher key and IV for the ciphering):
274
275.. code-block:: c
276
277   /*
278    * Check if length of provided cipher key is supported
279    * by the algorithm chosen.
280    */
281   if (options->ckey_param) {
282           if (check_supported_size(
283                           options->cipher_xform.cipher.key.length,
284                           cap->sym.cipher.key_size.min,
285                           cap->sym.cipher.key_size.max,
286                           cap->sym.cipher.key_size.increment)
287                                   != 0) {
288                   printf("Unsupported cipher key length\n");
289                   return -1;
290           }
291   /*
292    * Check if length of the cipher key to be randomly generated
293    * is supported by the algorithm chosen.
294    */
295   } else if (options->ckey_random_size != -1) {
296           if (check_supported_size(options->ckey_random_size,
297                           cap->sym.cipher.key_size.min,
298                           cap->sym.cipher.key_size.max,
299                           cap->sym.cipher.key_size.increment)
300                                   != 0) {
301                   printf("Unsupported cipher key length\n");
302                   return -1;
303           }
304           options->cipher_xform.cipher.key.length =
305                                   options->ckey_random_size;
306   /* No size provided, use minimum size. */
307   } else
308           options->cipher_xform.cipher.key.length =
309                           cap->sym.cipher.key_size.min;
310
311After all the checks, the device is configured and it is added to the
312crypto device list.
313
314**Note**:
315   The number of crypto devices that supports the specified crypto operation
316   must be at least the number of ports to be used.
317
318Session creation
319~~~~~~~~~~~~~~~~
320
321The crypto operation has a crypto session associated to it, which contains
322information such as the transform chain to perform (e.g. ciphering then hashing),
323pointers to the keys, lengths... etc.
324
325This session is created and is later attached to the crypto operation:
326
327.. code-block:: c
328
329   static struct rte_cryptodev_sym_session *
330   initialize_crypto_session(struct l2fwd_crypto_options *options,
331                   uint8_t cdev_id)
332   {
333           struct rte_crypto_sym_xform *first_xform;
334
335           if (options->xform_chain == L2FWD_CRYPTO_CIPHER_HASH) {
336                   first_xform = &options->cipher_xform;
337                   first_xform->next = &options->auth_xform;
338           } else if (options->xform_chain == L2FWD_CRYPTO_HASH_CIPHER) {
339                   first_xform = &options->auth_xform;
340                   first_xform->next = &options->cipher_xform;
341           } else if (options->xform_chain == L2FWD_CRYPTO_CIPHER_ONLY) {
342                   first_xform = &options->cipher_xform;
343           } else {
344                   first_xform = &options->auth_xform;
345           }
346
347           /* Setup Cipher Parameters */
348           return rte_cryptodev_sym_session_create(cdev_id, first_xform);
349   }
350
351   ...
352
353   port_cparams[i].session = initialize_crypto_session(options,
354                                port_cparams[i].dev_id);
355
356Crypto operation creation
357~~~~~~~~~~~~~~~~~~~~~~~~~
358
359Given N packets received from a RX PORT, N crypto operations are allocated
360and filled:
361
362.. code-block:: c
363
364   if (nb_rx) {
365   /*
366    * If we can't allocate a crypto_ops, then drop
367    * the rest of the burst and dequeue and
368    * process the packets to free offload structs
369    */
370   if (rte_crypto_op_bulk_alloc(
371                   l2fwd_crypto_op_pool,
372                   RTE_CRYPTO_OP_TYPE_SYMMETRIC,
373                   ops_burst, nb_rx) !=
374                                   nb_rx) {
375           for (j = 0; j < nb_rx; j++)
376                   rte_pktmbuf_free(pkts_burst[i]);
377
378           nb_rx = 0;
379   }
380
381After filling the crypto operation (including session attachment),
382the mbuf which will be transformed is attached to it::
383
384   op->sym->m_src = m;
385
386Since no destination mbuf is set, the source mbuf will be overwritten
387after the operation is done (in-place).
388
389Crypto operation enqueuing/dequeuing
390~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
391
392Once the operation has been created, it has to be enqueued in one of the crypto devices.
393Before doing so, for performance reasons, the operation stays in a buffer.
394When the buffer has enough operations (MAX_PKT_BURST), they are enqueued in the device,
395which will perform the operation at that moment:
396
397.. code-block:: c
398
399   static int
400   l2fwd_crypto_enqueue(struct rte_crypto_op *op,
401                   struct l2fwd_crypto_params *cparams)
402   {
403           unsigned lcore_id, len;
404           struct lcore_queue_conf *qconf;
405
406           lcore_id = rte_lcore_id();
407
408           qconf = &lcore_queue_conf[lcore_id];
409           len = qconf->op_buf[cparams->dev_id].len;
410           qconf->op_buf[cparams->dev_id].buffer[len] = op;
411           len++;
412
413           /* enough ops to be sent */
414           if (len == MAX_PKT_BURST) {
415                   l2fwd_crypto_send_burst(qconf, MAX_PKT_BURST, cparams);
416                   len = 0;
417           }
418
419           qconf->op_buf[cparams->dev_id].len = len;
420           return 0;
421   }
422
423   ...
424
425   static int
426   l2fwd_crypto_send_burst(struct lcore_queue_conf *qconf, unsigned n,
427                   struct l2fwd_crypto_params *cparams)
428   {
429           struct rte_crypto_op **op_buffer;
430           unsigned ret;
431
432           op_buffer = (struct rte_crypto_op **)
433                           qconf->op_buf[cparams->dev_id].buffer;
434
435           ret = rte_cryptodev_enqueue_burst(cparams->dev_id,
436                           cparams->qp_id, op_buffer, (uint16_t) n);
437
438           crypto_statistics[cparams->dev_id].enqueued += ret;
439           if (unlikely(ret < n)) {
440                   crypto_statistics[cparams->dev_id].errors += (n - ret);
441                   do {
442                           rte_pktmbuf_free(op_buffer[ret]->sym->m_src);
443                           rte_crypto_op_free(op_buffer[ret]);
444                   } while (++ret < n);
445           }
446
447           return 0;
448   }
449
450After this, the operations are dequeued from the device, and the transformed mbuf
451is extracted from the operation. Then, the operation is freed and the mbuf is
452forwarded as it is done in the L2 forwarding application.
453
454.. code-block:: c
455
456   /* Dequeue packets from Crypto device */
457   do {
458           nb_rx = rte_cryptodev_dequeue_burst(
459                           cparams->dev_id, cparams->qp_id,
460                           ops_burst, MAX_PKT_BURST);
461
462           crypto_statistics[cparams->dev_id].dequeued +=
463                           nb_rx;
464
465           /* Forward crypto'd packets */
466           for (j = 0; j < nb_rx; j++) {
467                   m = ops_burst[j]->sym->m_src;
468
469                   rte_crypto_op_free(ops_burst[j]);
470                   l2fwd_simple_forward(m, portid);
471           }
472   } while (nb_rx == MAX_PKT_BURST);
473