xref: /openbmc/qemu/backends/cryptodev-builtin.c (revision d307c28ca9dba7a0677035c9244198b05164c873)
1 /*
2  * QEMU Cryptodev backend for QEMU cipher APIs
3  *
4  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
5  *
6  * Authors:
7  *    Gonglei <arei.gonglei@huawei.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 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 "sysemu/cryptodev.h"
26 #include "hw/boards.h"
27 #include "qapi/error.h"
28 #include "standard-headers/linux/virtio_crypto.h"
29 #include "crypto/cipher.h"
30 
31 
32 /**
33  * @TYPE_CRYPTODEV_BACKEND_BUILTIN:
34  * name of backend that uses QEMU cipher API
35  */
36 #define TYPE_CRYPTODEV_BACKEND_BUILTIN "cryptodev-backend-builtin"
37 
38 #define CRYPTODEV_BACKEND_BUILTIN(obj) \
39     OBJECT_CHECK(CryptoDevBackendBuiltin, \
40                  (obj), TYPE_CRYPTODEV_BACKEND_BUILTIN)
41 
42 typedef struct CryptoDevBackendBuiltin
43                          CryptoDevBackendBuiltin;
44 
45 typedef struct CryptoDevBackendBuiltinSession {
46     QCryptoCipher *cipher;
47     uint8_t direction; /* encryption or decryption */
48     uint8_t type; /* cipher? hash? aead? */
49     QTAILQ_ENTRY(CryptoDevBackendBuiltinSession) next;
50 } CryptoDevBackendBuiltinSession;
51 
52 /* Max number of symmetric sessions */
53 #define MAX_NUM_SESSIONS 256
54 
55 #define CRYPTODEV_BUITLIN_MAX_AUTH_KEY_LEN    512
56 #define CRYPTODEV_BUITLIN_MAX_CIPHER_KEY_LEN  64
57 
58 struct CryptoDevBackendBuiltin {
59     CryptoDevBackend parent_obj;
60 
61     CryptoDevBackendBuiltinSession *sessions[MAX_NUM_SESSIONS];
62 };
63 
64 static void cryptodev_builtin_init(
65              CryptoDevBackend *backend, Error **errp)
66 {
67     /* Only support one queue */
68     int queues = backend->conf.peers.queues;
69     CryptoDevBackendClient *cc;
70 
71     if (queues != 1) {
72         error_setg(errp,
73                   "Only support one queue in cryptdov-builtin backend");
74         return;
75     }
76 
77     cc = cryptodev_backend_new_client(
78               "cryptodev-builtin", NULL);
79     cc->info_str = g_strdup_printf("cryptodev-builtin0");
80     cc->queue_index = 0;
81     backend->conf.peers.ccs[0] = cc;
82 
83     backend->conf.crypto_services =
84                          1u << VIRTIO_CRYPTO_SERVICE_CIPHER |
85                          1u << VIRTIO_CRYPTO_SERVICE_HASH |
86                          1u << VIRTIO_CRYPTO_SERVICE_MAC;
87     backend->conf.cipher_algo_l = 1u << VIRTIO_CRYPTO_CIPHER_AES_CBC;
88     backend->conf.hash_algo = 1u << VIRTIO_CRYPTO_HASH_SHA1;
89     /*
90      * Set the Maximum length of crypto request.
91      * Why this value? Just avoid to overflow when
92      * memory allocation for each crypto request.
93      */
94     backend->conf.max_size = LONG_MAX - sizeof(CryptoDevBackendSymOpInfo);
95     backend->conf.max_cipher_key_len = CRYPTODEV_BUITLIN_MAX_CIPHER_KEY_LEN;
96     backend->conf.max_auth_key_len = CRYPTODEV_BUITLIN_MAX_AUTH_KEY_LEN;
97 }
98 
99 static int
100 cryptodev_builtin_get_unused_session_index(
101                  CryptoDevBackendBuiltin *builtin)
102 {
103     size_t i;
104 
105     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
106         if (builtin->sessions[i] == NULL) {
107             return i;
108         }
109     }
110 
111     return -1;
112 }
113 
114 #define AES_KEYSIZE_128 16
115 #define AES_KEYSIZE_192 24
116 #define AES_KEYSIZE_256 32
117 #define AES_KEYSIZE_128_XTS AES_KEYSIZE_256
118 #define AES_KEYSIZE_256_XTS 64
119 
120 static int
121 cryptodev_builtin_get_aes_algo(uint32_t key_len, int mode, Error **errp)
122 {
123     int algo;
124 
125     if (key_len == AES_KEYSIZE_128) {
126         algo = QCRYPTO_CIPHER_ALG_AES_128;
127     } else if (key_len == AES_KEYSIZE_192) {
128         algo = QCRYPTO_CIPHER_ALG_AES_192;
129     } else if (key_len == AES_KEYSIZE_256) { /* equals AES_KEYSIZE_128_XTS */
130         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
131             algo = QCRYPTO_CIPHER_ALG_AES_128;
132         } else {
133             algo = QCRYPTO_CIPHER_ALG_AES_256;
134         }
135     } else if (key_len == AES_KEYSIZE_256_XTS) {
136         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
137             algo = QCRYPTO_CIPHER_ALG_AES_256;
138         } else {
139             goto err;
140         }
141     } else {
142         goto err;
143     }
144 
145     return algo;
146 
147 err:
148    error_setg(errp, "Unsupported key length :%u", key_len);
149    return -1;
150 }
151 
152 static int cryptodev_builtin_create_cipher_session(
153                     CryptoDevBackendBuiltin *builtin,
154                     CryptoDevBackendSymSessionInfo *sess_info,
155                     Error **errp)
156 {
157     int algo;
158     int mode;
159     QCryptoCipher *cipher;
160     int index;
161     CryptoDevBackendBuiltinSession *sess;
162 
163     if (sess_info->op_type != VIRTIO_CRYPTO_SYM_OP_CIPHER) {
164         error_setg(errp, "Unsupported optype :%u", sess_info->op_type);
165         return -1;
166     }
167 
168     index = cryptodev_builtin_get_unused_session_index(builtin);
169     if (index < 0) {
170         error_setg(errp, "Total number of sessions created exceeds %u",
171                   MAX_NUM_SESSIONS);
172         return -1;
173     }
174 
175     switch (sess_info->cipher_alg) {
176     case VIRTIO_CRYPTO_CIPHER_AES_ECB:
177         mode = QCRYPTO_CIPHER_MODE_ECB;
178         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
179                                                     mode, errp);
180         if (algo < 0)  {
181             return -1;
182         }
183         break;
184     case VIRTIO_CRYPTO_CIPHER_AES_CBC:
185         mode = QCRYPTO_CIPHER_MODE_CBC;
186         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
187                                                     mode, errp);
188         if (algo < 0)  {
189             return -1;
190         }
191         break;
192     case VIRTIO_CRYPTO_CIPHER_AES_CTR:
193         mode = QCRYPTO_CIPHER_MODE_CTR;
194         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
195                                                     mode, errp);
196         if (algo < 0)  {
197             return -1;
198         }
199         break;
200     case VIRTIO_CRYPTO_CIPHER_AES_XTS:
201         mode = QCRYPTO_CIPHER_MODE_XTS;
202         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
203                                                     mode, errp);
204         if (algo < 0)  {
205             return -1;
206         }
207         break;
208     case VIRTIO_CRYPTO_CIPHER_3DES_ECB:
209         mode = QCRYPTO_CIPHER_MODE_ECB;
210         algo = QCRYPTO_CIPHER_ALG_3DES;
211         break;
212     case VIRTIO_CRYPTO_CIPHER_3DES_CBC:
213         mode = QCRYPTO_CIPHER_MODE_CBC;
214         algo = QCRYPTO_CIPHER_ALG_3DES;
215         break;
216     case VIRTIO_CRYPTO_CIPHER_3DES_CTR:
217         mode = QCRYPTO_CIPHER_MODE_CTR;
218         algo = QCRYPTO_CIPHER_ALG_3DES;
219         break;
220     default:
221         error_setg(errp, "Unsupported cipher alg :%u",
222                    sess_info->cipher_alg);
223         return -1;
224     }
225 
226     cipher = qcrypto_cipher_new(algo, mode,
227                                sess_info->cipher_key,
228                                sess_info->key_len,
229                                errp);
230     if (!cipher) {
231         return -1;
232     }
233 
234     sess = g_new0(CryptoDevBackendBuiltinSession, 1);
235     sess->cipher = cipher;
236     sess->direction = sess_info->direction;
237     sess->type = sess_info->op_type;
238 
239     builtin->sessions[index] = sess;
240 
241     return index;
242 }
243 
244 static int64_t cryptodev_builtin_sym_create_session(
245            CryptoDevBackend *backend,
246            CryptoDevBackendSymSessionInfo *sess_info,
247            uint32_t queue_index, Error **errp)
248 {
249     CryptoDevBackendBuiltin *builtin =
250                       CRYPTODEV_BACKEND_BUILTIN(backend);
251     int64_t session_id = -1;
252     int ret;
253 
254     switch (sess_info->op_code) {
255     case VIRTIO_CRYPTO_CIPHER_CREATE_SESSION:
256         ret = cryptodev_builtin_create_cipher_session(
257                            builtin, sess_info, errp);
258         if (ret < 0) {
259             return ret;
260         } else {
261             session_id = ret;
262         }
263         break;
264     case VIRTIO_CRYPTO_HASH_CREATE_SESSION:
265     case VIRTIO_CRYPTO_MAC_CREATE_SESSION:
266     default:
267         error_setg(errp, "Unsupported opcode :%" PRIu32 "",
268                    sess_info->op_code);
269         return -1;
270     }
271 
272     return session_id;
273 }
274 
275 static int cryptodev_builtin_sym_close_session(
276            CryptoDevBackend *backend,
277            uint64_t session_id,
278            uint32_t queue_index, Error **errp)
279 {
280     CryptoDevBackendBuiltin *builtin =
281                       CRYPTODEV_BACKEND_BUILTIN(backend);
282 
283     if (session_id >= MAX_NUM_SESSIONS ||
284               builtin->sessions[session_id] == NULL) {
285         error_setg(errp, "Cannot find a valid session id: %" PRIu64 "",
286                       session_id);
287         return -1;
288     }
289 
290     qcrypto_cipher_free(builtin->sessions[session_id]->cipher);
291     g_free(builtin->sessions[session_id]);
292     builtin->sessions[session_id] = NULL;
293     return 0;
294 }
295 
296 static int cryptodev_builtin_sym_operation(
297                  CryptoDevBackend *backend,
298                  CryptoDevBackendSymOpInfo *op_info,
299                  uint32_t queue_index, Error **errp)
300 {
301     CryptoDevBackendBuiltin *builtin =
302                       CRYPTODEV_BACKEND_BUILTIN(backend);
303     CryptoDevBackendBuiltinSession *sess;
304     int ret;
305 
306     if (op_info->session_id >= MAX_NUM_SESSIONS ||
307               builtin->sessions[op_info->session_id] == NULL) {
308         error_setg(errp, "Cannot find a valid session id: %" PRIu64 "",
309                    op_info->session_id);
310         return -VIRTIO_CRYPTO_INVSESS;
311     }
312 
313     if (op_info->op_type == VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING) {
314         error_setg(errp,
315                "Algorithm chain is unsupported for cryptdoev-builtin");
316         return -VIRTIO_CRYPTO_NOTSUPP;
317     }
318 
319     sess = builtin->sessions[op_info->session_id];
320 
321     ret = qcrypto_cipher_setiv(sess->cipher, op_info->iv,
322                                op_info->iv_len, errp);
323     if (ret < 0) {
324         return -VIRTIO_CRYPTO_ERR;
325     }
326 
327     if (sess->direction == VIRTIO_CRYPTO_OP_ENCRYPT) {
328         ret = qcrypto_cipher_encrypt(sess->cipher, op_info->src,
329                                      op_info->dst, op_info->src_len, errp);
330         if (ret < 0) {
331             return -VIRTIO_CRYPTO_ERR;
332         }
333     } else {
334         ret = qcrypto_cipher_decrypt(sess->cipher, op_info->src,
335                                      op_info->dst, op_info->src_len, errp);
336         if (ret < 0) {
337             return -VIRTIO_CRYPTO_ERR;
338         }
339     }
340     return VIRTIO_CRYPTO_OK;
341 }
342 
343 static void cryptodev_builtin_cleanup(
344              CryptoDevBackend *backend,
345              Error **errp)
346 {
347     CryptoDevBackendBuiltin *builtin =
348                       CRYPTODEV_BACKEND_BUILTIN(backend);
349     size_t i;
350     int queues = backend->conf.peers.queues;
351     CryptoDevBackendClient *cc;
352 
353     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
354         if (builtin->sessions[i] != NULL) {
355             cryptodev_builtin_sym_close_session(
356                     backend, i, 0, errp);
357         }
358     }
359 
360     assert(queues == 1);
361 
362     for (i = 0; i < queues; i++) {
363         cc = backend->conf.peers.ccs[i];
364         if (cc) {
365             cryptodev_backend_free_client(cc);
366             backend->conf.peers.ccs[i] = NULL;
367         }
368     }
369 }
370 
371 static void
372 cryptodev_builtin_class_init(ObjectClass *oc, void *data)
373 {
374     CryptoDevBackendClass *bc = CRYPTODEV_BACKEND_CLASS(oc);
375 
376     bc->init = cryptodev_builtin_init;
377     bc->cleanup = cryptodev_builtin_cleanup;
378     bc->create_session = cryptodev_builtin_sym_create_session;
379     bc->close_session = cryptodev_builtin_sym_close_session;
380     bc->do_sym_op = cryptodev_builtin_sym_operation;
381 }
382 
383 static const TypeInfo cryptodev_builtin_info = {
384     .name = TYPE_CRYPTODEV_BACKEND_BUILTIN,
385     .parent = TYPE_CRYPTODEV_BACKEND,
386     .class_init = cryptodev_builtin_class_init,
387     .instance_size = sizeof(CryptoDevBackendBuiltin),
388 };
389 
390 static void
391 cryptodev_builtin_register_types(void)
392 {
393     type_register_static(&cryptodev_builtin_info);
394 }
395 
396 type_init(cryptodev_builtin_register_types);
397