xref: /openbmc/qemu/backends/cryptodev-lkcf.c (revision 7d87775f)
1 /*
2  * QEMU Cryptodev backend for QEMU cipher APIs
3  *
4  * Copyright (c) 2022 Bytedance.Inc
5  *
6  * Authors:
7  *    lei he <helei.sig11@bytedance.com>
8  *
9  * This library is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * This library is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
21  *
22  */
23 
24 #include "qemu/osdep.h"
25 #include "crypto/cipher.h"
26 #include "crypto/akcipher.h"
27 #include "qapi/error.h"
28 #include "qemu/main-loop.h"
29 #include "qemu/thread.h"
30 #include "qemu/error-report.h"
31 #include "qemu/queue.h"
32 #include "qom/object.h"
33 #include "sysemu/cryptodev.h"
34 #include "standard-headers/linux/virtio_crypto.h"
35 
36 #include <keyutils.h>
37 #include <sys/eventfd.h>
38 
39 /**
40  * @TYPE_CRYPTODEV_BACKEND_LKCF:
41  * name of backend that uses linux kernel crypto framework
42  */
43 #define TYPE_CRYPTODEV_BACKEND_LKCF "cryptodev-backend-lkcf"
44 
45 OBJECT_DECLARE_SIMPLE_TYPE(CryptoDevBackendLKCF, CRYPTODEV_BACKEND_LKCF)
46 
47 #define INVALID_KEY_ID -1
48 #define MAX_SESSIONS 256
49 #define NR_WORKER_THREAD 64
50 
51 #define KCTL_KEY_TYPE_PKEY "asymmetric"
52 /**
53  * Here the key is uploaded to the thread-keyring of worker thread, at least
54  * util linux-6.0:
55  * 1. process keyring seems to behave unexpectedly if main-thread does not
56  * create the keyring before creating any other thread.
57  * 2. at present, the guest kernel never perform multiple operations on a
58  * session.
59  * 3. it can reduce the load of the main-loop because the key passed by the
60  * guest kernel has been already checked.
61  */
62 #define KCTL_KEY_RING KEY_SPEC_THREAD_KEYRING
63 
64 typedef struct CryptoDevBackendLKCFSession {
65     uint8_t *key;
66     size_t keylen;
67     QCryptoAkCipherKeyType keytype;
68     QCryptoAkCipherOptions akcipher_opts;
69 } CryptoDevBackendLKCFSession;
70 
71 typedef struct CryptoDevBackendLKCF CryptoDevBackendLKCF;
72 typedef struct CryptoDevLKCFTask CryptoDevLKCFTask;
73 struct CryptoDevLKCFTask {
74     CryptoDevBackendLKCFSession *sess;
75     CryptoDevBackendOpInfo *op_info;
76     CryptoDevCompletionFunc cb;
77     void *opaque;
78     int status;
79     CryptoDevBackendLKCF *lkcf;
80     QSIMPLEQ_ENTRY(CryptoDevLKCFTask) queue;
81 };
82 
83 typedef struct CryptoDevBackendLKCF {
84     CryptoDevBackend parent_obj;
85     CryptoDevBackendLKCFSession *sess[MAX_SESSIONS];
86     QSIMPLEQ_HEAD(, CryptoDevLKCFTask) requests;
87     QSIMPLEQ_HEAD(, CryptoDevLKCFTask) responses;
88     QemuMutex mutex;
89     QemuCond cond;
90     QemuMutex rsp_mutex;
91 
92     /**
93      * There is no async interface for asymmetric keys like AF_ALG sockets,
94      * we don't seem to have better way than create a lots of thread.
95      */
96     QemuThread worker_threads[NR_WORKER_THREAD];
97     bool running;
98     int eventfd;
99 } CryptoDevBackendLKCF;
100 
101 static void *cryptodev_lkcf_worker(void *arg);
102 static int cryptodev_lkcf_close_session(CryptoDevBackend *backend,
103                                         uint64_t session_id,
104                                         uint32_t queue_index,
105                                         CryptoDevCompletionFunc cb,
106                                         void *opaque);
107 
108 static void cryptodev_lkcf_handle_response(void *opaque)
109 {
110     CryptoDevBackendLKCF *lkcf = (CryptoDevBackendLKCF *)opaque;
111     QSIMPLEQ_HEAD(, CryptoDevLKCFTask) responses;
112     CryptoDevLKCFTask *task, *next;
113     eventfd_t nevent;
114 
115     QSIMPLEQ_INIT(&responses);
116     eventfd_read(lkcf->eventfd, &nevent);
117 
118     qemu_mutex_lock(&lkcf->rsp_mutex);
119     QSIMPLEQ_PREPEND(&responses, &lkcf->responses);
120     qemu_mutex_unlock(&lkcf->rsp_mutex);
121 
122     QSIMPLEQ_FOREACH_SAFE(task, &responses, queue, next) {
123         if (task->cb) {
124             task->cb(task->opaque, task->status);
125         }
126         g_free(task);
127     }
128 }
129 
130 static int cryptodev_lkcf_set_op_desc(QCryptoAkCipherOptions *opts,
131                                       char *key_desc,
132                                       size_t desc_len,
133                                       Error **errp)
134 {
135     QCryptoAkCipherOptionsRSA *rsa_opt;
136     if (opts->alg != QCRYPTO_AK_CIPHER_ALGO_RSA) {
137         error_setg(errp, "Unsupported alg: %u", opts->alg);
138         return -1;
139     }
140 
141     rsa_opt = &opts->u.rsa;
142     if (rsa_opt->padding_alg == QCRYPTO_RSA_PADDING_ALGO_PKCS1) {
143         snprintf(key_desc, desc_len, "enc=%s hash=%s",
144                  QCryptoRSAPaddingAlgo_str(rsa_opt->padding_alg),
145                  QCryptoHashAlgo_str(rsa_opt->hash_alg));
146 
147     } else {
148         snprintf(key_desc, desc_len, "enc=%s",
149                  QCryptoRSAPaddingAlgo_str(rsa_opt->padding_alg));
150     }
151     return 0;
152 }
153 
154 static int cryptodev_lkcf_set_rsa_opt(int virtio_padding_alg,
155                                       int virtio_hash_alg,
156                                       QCryptoAkCipherOptionsRSA *opt,
157                                       Error **errp)
158 {
159     if (virtio_padding_alg == VIRTIO_CRYPTO_RSA_PKCS1_PADDING) {
160         opt->padding_alg = QCRYPTO_RSA_PADDING_ALGO_PKCS1;
161 
162         switch (virtio_hash_alg) {
163         case VIRTIO_CRYPTO_RSA_MD5:
164             opt->hash_alg = QCRYPTO_HASH_ALGO_MD5;
165             break;
166 
167         case VIRTIO_CRYPTO_RSA_SHA1:
168             opt->hash_alg = QCRYPTO_HASH_ALGO_SHA1;
169             break;
170 
171         case VIRTIO_CRYPTO_RSA_SHA256:
172             opt->hash_alg = QCRYPTO_HASH_ALGO_SHA256;
173             break;
174 
175         case VIRTIO_CRYPTO_RSA_SHA512:
176             opt->hash_alg = QCRYPTO_HASH_ALGO_SHA512;
177             break;
178 
179         default:
180             error_setg(errp, "Unsupported rsa hash algo: %d", virtio_hash_alg);
181             return -1;
182         }
183         return 0;
184     }
185 
186     if (virtio_padding_alg == VIRTIO_CRYPTO_RSA_RAW_PADDING) {
187         opt->padding_alg = QCRYPTO_RSA_PADDING_ALGO_RAW;
188         return 0;
189     }
190 
191     error_setg(errp, "Unsupported rsa padding algo: %u", virtio_padding_alg);
192     return -1;
193 }
194 
195 static int cryptodev_lkcf_get_unused_session_index(CryptoDevBackendLKCF *lkcf)
196 {
197     size_t i;
198 
199     for (i = 0; i < MAX_SESSIONS; i++) {
200         if (lkcf->sess[i] == NULL) {
201             return i;
202         }
203     }
204     return -1;
205 }
206 
207 static void cryptodev_lkcf_init(CryptoDevBackend *backend, Error **errp)
208 {
209     /* Only support one queue */
210     int queues = backend->conf.peers.queues, i;
211     CryptoDevBackendClient *cc;
212     CryptoDevBackendLKCF *lkcf =
213         CRYPTODEV_BACKEND_LKCF(backend);
214 
215     if (queues != 1) {
216         error_setg(errp,
217                    "Only support one queue in cryptodev-builtin backend");
218         return;
219     }
220     lkcf->eventfd = eventfd(0, 0);
221     if (lkcf->eventfd < 0) {
222         error_setg(errp, "Failed to create eventfd: %d", errno);
223         return;
224     }
225 
226     cc = cryptodev_backend_new_client();
227     cc->info_str = g_strdup_printf("cryptodev-lkcf0");
228     cc->queue_index = 0;
229     cc->type = QCRYPTODEV_BACKEND_TYPE_LKCF;
230     backend->conf.peers.ccs[0] = cc;
231 
232     backend->conf.crypto_services =
233         1u << QCRYPTODEV_BACKEND_SERVICE_TYPE_AKCIPHER;
234     backend->conf.akcipher_algo = 1u << VIRTIO_CRYPTO_AKCIPHER_RSA;
235     lkcf->running = true;
236 
237     QSIMPLEQ_INIT(&lkcf->requests);
238     QSIMPLEQ_INIT(&lkcf->responses);
239     qemu_mutex_init(&lkcf->mutex);
240     qemu_mutex_init(&lkcf->rsp_mutex);
241     qemu_cond_init(&lkcf->cond);
242     for (i = 0; i < NR_WORKER_THREAD; i++) {
243         qemu_thread_create(&lkcf->worker_threads[i], "lkcf-worker",
244                            cryptodev_lkcf_worker, lkcf, 0);
245     }
246     qemu_set_fd_handler(
247         lkcf->eventfd, cryptodev_lkcf_handle_response, NULL, lkcf);
248     cryptodev_backend_set_ready(backend, true);
249 }
250 
251 static void cryptodev_lkcf_cleanup(CryptoDevBackend *backend, Error **errp)
252 {
253     CryptoDevBackendLKCF *lkcf = CRYPTODEV_BACKEND_LKCF(backend);
254     size_t i;
255     int queues = backend->conf.peers.queues;
256     CryptoDevBackendClient *cc;
257     CryptoDevLKCFTask *task, *next;
258 
259     qemu_mutex_lock(&lkcf->mutex);
260     lkcf->running = false;
261     qemu_mutex_unlock(&lkcf->mutex);
262     qemu_cond_broadcast(&lkcf->cond);
263 
264     close(lkcf->eventfd);
265     for (i = 0; i < NR_WORKER_THREAD; i++) {
266         qemu_thread_join(&lkcf->worker_threads[i]);
267     }
268 
269     QSIMPLEQ_FOREACH_SAFE(task, &lkcf->requests, queue, next) {
270         if (task->cb) {
271             task->cb(task->opaque, task->status);
272         }
273         g_free(task);
274     }
275 
276     QSIMPLEQ_FOREACH_SAFE(task, &lkcf->responses, queue, next) {
277         if (task->cb) {
278             task->cb(task->opaque, task->status);
279         }
280         g_free(task);
281     }
282 
283     qemu_mutex_destroy(&lkcf->mutex);
284     qemu_cond_destroy(&lkcf->cond);
285     qemu_mutex_destroy(&lkcf->rsp_mutex);
286 
287     for (i = 0; i < MAX_SESSIONS; i++) {
288         if (lkcf->sess[i] != NULL) {
289             cryptodev_lkcf_close_session(backend, i, 0, NULL, NULL);
290         }
291     }
292 
293     for (i = 0; i < queues; i++) {
294         cc = backend->conf.peers.ccs[i];
295         if (cc) {
296             cryptodev_backend_free_client(cc);
297             backend->conf.peers.ccs[i] = NULL;
298         }
299     }
300 
301     cryptodev_backend_set_ready(backend, false);
302 }
303 
304 static void cryptodev_lkcf_execute_task(CryptoDevLKCFTask *task)
305 {
306     CryptoDevBackendLKCFSession *session = task->sess;
307     CryptoDevBackendAsymOpInfo *asym_op_info;
308     bool kick = false;
309     int ret, status, op_code = task->op_info->op_code;
310     size_t p8info_len;
311     g_autofree uint8_t *p8info = NULL;
312     Error *local_error = NULL;
313     key_serial_t key_id = INVALID_KEY_ID;
314     char op_desc[64];
315     g_autoptr(QCryptoAkCipher) akcipher = NULL;
316 
317     /**
318      * We only offload private key session:
319      * 1. currently, the Linux kernel can only accept public key wrapped
320      * with X.509 certificates, but unfortunately the cost of making a
321      * ceritificate with public key is too expensive.
322      * 2. generally, public key related compution is fast, just compute it with
323      * thread-pool.
324      */
325     if (session->keytype == QCRYPTO_AK_CIPHER_KEY_TYPE_PRIVATE) {
326         if (qcrypto_akcipher_export_p8info(&session->akcipher_opts,
327                                            session->key, session->keylen,
328                                            &p8info, &p8info_len,
329                                            &local_error) != 0 ||
330             cryptodev_lkcf_set_op_desc(&session->akcipher_opts, op_desc,
331                                        sizeof(op_desc), &local_error) != 0) {
332             error_report_err(local_error);
333         } else {
334             key_id = add_key(KCTL_KEY_TYPE_PKEY, "lkcf-backend-priv-key",
335                              p8info, p8info_len, KCTL_KEY_RING);
336         }
337     }
338 
339     if (key_id < 0) {
340         if (!qcrypto_akcipher_supports(&session->akcipher_opts)) {
341             status = -VIRTIO_CRYPTO_NOTSUPP;
342             goto out;
343         }
344         akcipher = qcrypto_akcipher_new(&session->akcipher_opts,
345                                         session->keytype,
346                                         session->key, session->keylen,
347                                         &local_error);
348         if (!akcipher) {
349             status = -VIRTIO_CRYPTO_ERR;
350             goto out;
351         }
352     }
353 
354     asym_op_info = task->op_info->u.asym_op_info;
355     switch (op_code) {
356     case VIRTIO_CRYPTO_AKCIPHER_ENCRYPT:
357         if (key_id >= 0) {
358             ret = keyctl_pkey_encrypt(key_id, op_desc,
359                 asym_op_info->src, asym_op_info->src_len,
360                 asym_op_info->dst, asym_op_info->dst_len);
361         } else {
362             ret = qcrypto_akcipher_encrypt(akcipher,
363                 asym_op_info->src, asym_op_info->src_len,
364                 asym_op_info->dst, asym_op_info->dst_len, &local_error);
365         }
366         break;
367 
368     case VIRTIO_CRYPTO_AKCIPHER_DECRYPT:
369         if (key_id >= 0) {
370             ret = keyctl_pkey_decrypt(key_id, op_desc,
371                 asym_op_info->src, asym_op_info->src_len,
372                 asym_op_info->dst, asym_op_info->dst_len);
373         } else {
374             ret = qcrypto_akcipher_decrypt(akcipher,
375                 asym_op_info->src, asym_op_info->src_len,
376                 asym_op_info->dst, asym_op_info->dst_len, &local_error);
377         }
378         break;
379 
380     case VIRTIO_CRYPTO_AKCIPHER_SIGN:
381         if (key_id >= 0) {
382             ret = keyctl_pkey_sign(key_id, op_desc,
383                 asym_op_info->src, asym_op_info->src_len,
384                 asym_op_info->dst, asym_op_info->dst_len);
385         } else {
386             ret = qcrypto_akcipher_sign(akcipher,
387                 asym_op_info->src, asym_op_info->src_len,
388                 asym_op_info->dst, asym_op_info->dst_len, &local_error);
389         }
390         break;
391 
392     case VIRTIO_CRYPTO_AKCIPHER_VERIFY:
393         if (key_id >= 0) {
394             ret = keyctl_pkey_verify(key_id, op_desc,
395                 asym_op_info->src, asym_op_info->src_len,
396                 asym_op_info->dst, asym_op_info->dst_len);
397         } else {
398             ret = qcrypto_akcipher_verify(akcipher,
399                 asym_op_info->src, asym_op_info->src_len,
400                 asym_op_info->dst, asym_op_info->dst_len, &local_error);
401         }
402         break;
403 
404     default:
405         error_setg(&local_error, "Unknown opcode: %u", op_code);
406         status = -VIRTIO_CRYPTO_ERR;
407         goto out;
408     }
409 
410     if (ret < 0) {
411         if (!local_error) {
412             if (errno != EKEYREJECTED) {
413                 error_report("Failed do operation with keyctl: %d", errno);
414             }
415         } else {
416             error_report_err(local_error);
417         }
418         status = op_code == VIRTIO_CRYPTO_AKCIPHER_VERIFY ?
419             -VIRTIO_CRYPTO_KEY_REJECTED : -VIRTIO_CRYPTO_ERR;
420     } else {
421         status = VIRTIO_CRYPTO_OK;
422         asym_op_info->dst_len = ret;
423     }
424 
425 out:
426     if (key_id >= 0) {
427         keyctl_unlink(key_id, KCTL_KEY_RING);
428     }
429     task->status = status;
430 
431     qemu_mutex_lock(&task->lkcf->rsp_mutex);
432     if (QSIMPLEQ_EMPTY(&task->lkcf->responses)) {
433         kick = true;
434     }
435     QSIMPLEQ_INSERT_TAIL(&task->lkcf->responses, task, queue);
436     qemu_mutex_unlock(&task->lkcf->rsp_mutex);
437 
438     if (kick) {
439         eventfd_write(task->lkcf->eventfd, 1);
440     }
441 }
442 
443 static void *cryptodev_lkcf_worker(void *arg)
444 {
445     CryptoDevBackendLKCF *backend = (CryptoDevBackendLKCF *)arg;
446     CryptoDevLKCFTask *task;
447 
448     for (;;) {
449         task = NULL;
450         qemu_mutex_lock(&backend->mutex);
451         while (backend->running && QSIMPLEQ_EMPTY(&backend->requests)) {
452             qemu_cond_wait(&backend->cond, &backend->mutex);
453         }
454         if (backend->running) {
455             task = QSIMPLEQ_FIRST(&backend->requests);
456             QSIMPLEQ_REMOVE_HEAD(&backend->requests, queue);
457         }
458         qemu_mutex_unlock(&backend->mutex);
459 
460         /* stopped */
461         if (!task) {
462             break;
463         }
464         cryptodev_lkcf_execute_task(task);
465    }
466 
467    return NULL;
468 }
469 
470 static int cryptodev_lkcf_operation(
471     CryptoDevBackend *backend,
472     CryptoDevBackendOpInfo *op_info)
473 {
474     CryptoDevBackendLKCF *lkcf =
475         CRYPTODEV_BACKEND_LKCF(backend);
476     CryptoDevBackendLKCFSession *sess;
477     QCryptodevBackendAlgoType algtype = op_info->algtype;
478     CryptoDevLKCFTask *task;
479 
480     if (op_info->session_id >= MAX_SESSIONS ||
481         lkcf->sess[op_info->session_id] == NULL) {
482         error_report("Cannot find a valid session id: %" PRIu64 "",
483                      op_info->session_id);
484         return -VIRTIO_CRYPTO_INVSESS;
485     }
486 
487     sess = lkcf->sess[op_info->session_id];
488     if (algtype != QCRYPTODEV_BACKEND_ALGO_TYPE_ASYM) {
489         error_report("algtype not supported: %u", algtype);
490         return -VIRTIO_CRYPTO_NOTSUPP;
491     }
492 
493     task = g_new0(CryptoDevLKCFTask, 1);
494     task->op_info = op_info;
495     task->cb = op_info->cb;
496     task->opaque = op_info->opaque;
497     task->sess = sess;
498     task->lkcf = lkcf;
499     task->status = -VIRTIO_CRYPTO_ERR;
500 
501     qemu_mutex_lock(&lkcf->mutex);
502     QSIMPLEQ_INSERT_TAIL(&lkcf->requests, task, queue);
503     qemu_mutex_unlock(&lkcf->mutex);
504     qemu_cond_signal(&lkcf->cond);
505 
506     return VIRTIO_CRYPTO_OK;
507 }
508 
509 static int cryptodev_lkcf_create_asym_session(
510     CryptoDevBackendLKCF *lkcf,
511     CryptoDevBackendAsymSessionInfo *sess_info,
512     uint64_t *session_id)
513 {
514     Error *local_error = NULL;
515     int index;
516     g_autofree CryptoDevBackendLKCFSession *sess =
517         g_new0(CryptoDevBackendLKCFSession, 1);
518 
519     switch (sess_info->algo) {
520     case VIRTIO_CRYPTO_AKCIPHER_RSA:
521         sess->akcipher_opts.alg = QCRYPTO_AK_CIPHER_ALGO_RSA;
522         if (cryptodev_lkcf_set_rsa_opt(
523             sess_info->u.rsa.padding_algo, sess_info->u.rsa.hash_algo,
524             &sess->akcipher_opts.u.rsa, &local_error) != 0) {
525             error_report_err(local_error);
526             return -VIRTIO_CRYPTO_ERR;
527         }
528         break;
529 
530     default:
531         error_report("Unsupported asym alg %u", sess_info->algo);
532         return -VIRTIO_CRYPTO_NOTSUPP;
533     }
534 
535     switch (sess_info->keytype) {
536     case VIRTIO_CRYPTO_AKCIPHER_KEY_TYPE_PUBLIC:
537         sess->keytype = QCRYPTO_AK_CIPHER_KEY_TYPE_PUBLIC;
538         break;
539 
540     case VIRTIO_CRYPTO_AKCIPHER_KEY_TYPE_PRIVATE:
541         sess->keytype = QCRYPTO_AK_CIPHER_KEY_TYPE_PRIVATE;
542         break;
543 
544     default:
545         error_report("Unknown akcipher keytype: %u", sess_info->keytype);
546         return -VIRTIO_CRYPTO_ERR;
547     }
548 
549     index = cryptodev_lkcf_get_unused_session_index(lkcf);
550     if (index < 0) {
551         error_report("Total number of sessions created exceeds %u",
552                      MAX_SESSIONS);
553         return -VIRTIO_CRYPTO_ERR;
554     }
555 
556     sess->keylen = sess_info->keylen;
557     sess->key = g_malloc(sess_info->keylen);
558     memcpy(sess->key, sess_info->key, sess_info->keylen);
559 
560     lkcf->sess[index] = g_steal_pointer(&sess);
561     *session_id = index;
562 
563     return VIRTIO_CRYPTO_OK;
564 }
565 
566 static int cryptodev_lkcf_create_session(
567     CryptoDevBackend *backend,
568     CryptoDevBackendSessionInfo *sess_info,
569     uint32_t queue_index,
570     CryptoDevCompletionFunc cb,
571     void *opaque)
572 {
573     CryptoDevBackendAsymSessionInfo *asym_sess_info;
574     CryptoDevBackendLKCF *lkcf =
575         CRYPTODEV_BACKEND_LKCF(backend);
576     int ret;
577 
578     switch (sess_info->op_code) {
579     case VIRTIO_CRYPTO_AKCIPHER_CREATE_SESSION:
580         asym_sess_info = &sess_info->u.asym_sess_info;
581         ret = cryptodev_lkcf_create_asym_session(
582             lkcf, asym_sess_info, &sess_info->session_id);
583         break;
584 
585     default:
586         ret = -VIRTIO_CRYPTO_NOTSUPP;
587         error_report("Unsupported opcode: %" PRIu32 "",
588                      sess_info->op_code);
589         break;
590     }
591     if (cb) {
592         cb(opaque, ret);
593     }
594     return 0;
595 }
596 
597 static int cryptodev_lkcf_close_session(CryptoDevBackend *backend,
598                                         uint64_t session_id,
599                                         uint32_t queue_index,
600                                         CryptoDevCompletionFunc cb,
601                                         void *opaque)
602 {
603     CryptoDevBackendLKCF *lkcf = CRYPTODEV_BACKEND_LKCF(backend);
604     CryptoDevBackendLKCFSession *session;
605 
606     assert(session_id < MAX_SESSIONS && lkcf->sess[session_id]);
607     session = lkcf->sess[session_id];
608     lkcf->sess[session_id] = NULL;
609 
610     g_free(session->key);
611     g_free(session);
612 
613     if (cb) {
614         cb(opaque, VIRTIO_CRYPTO_OK);
615     }
616     return 0;
617 }
618 
619 static void cryptodev_lkcf_class_init(ObjectClass *oc, void *data)
620 {
621     CryptoDevBackendClass *bc = CRYPTODEV_BACKEND_CLASS(oc);
622 
623     bc->init = cryptodev_lkcf_init;
624     bc->cleanup = cryptodev_lkcf_cleanup;
625     bc->create_session = cryptodev_lkcf_create_session;
626     bc->close_session = cryptodev_lkcf_close_session;
627     bc->do_op = cryptodev_lkcf_operation;
628 }
629 
630 static const TypeInfo cryptodev_builtin_info = {
631     .name = TYPE_CRYPTODEV_BACKEND_LKCF,
632     .parent = TYPE_CRYPTODEV_BACKEND,
633     .class_init = cryptodev_lkcf_class_init,
634     .instance_size = sizeof(CryptoDevBackendLKCF),
635 };
636 
637 static void cryptodev_lkcf_register_types(void)
638 {
639     type_register_static(&cryptodev_builtin_info);
640 }
641 
642 type_init(cryptodev_lkcf_register_types);
643