xref: /openbmc/qemu/backends/cryptodev-builtin.c (revision ba632924)
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     cc->type = CRYPTODEV_BACKEND_TYPE_BUILTIN;
82     backend->conf.peers.ccs[0] = cc;
83 
84     backend->conf.crypto_services =
85                          1u << VIRTIO_CRYPTO_SERVICE_CIPHER |
86                          1u << VIRTIO_CRYPTO_SERVICE_HASH |
87                          1u << VIRTIO_CRYPTO_SERVICE_MAC;
88     backend->conf.cipher_algo_l = 1u << VIRTIO_CRYPTO_CIPHER_AES_CBC;
89     backend->conf.hash_algo = 1u << VIRTIO_CRYPTO_HASH_SHA1;
90     /*
91      * Set the Maximum length of crypto request.
92      * Why this value? Just avoid to overflow when
93      * memory allocation for each crypto request.
94      */
95     backend->conf.max_size = LONG_MAX - sizeof(CryptoDevBackendSymOpInfo);
96     backend->conf.max_cipher_key_len = CRYPTODEV_BUITLIN_MAX_CIPHER_KEY_LEN;
97     backend->conf.max_auth_key_len = CRYPTODEV_BUITLIN_MAX_AUTH_KEY_LEN;
98 
99     cryptodev_backend_set_ready(backend, true);
100 }
101 
102 static int
103 cryptodev_builtin_get_unused_session_index(
104                  CryptoDevBackendBuiltin *builtin)
105 {
106     size_t i;
107 
108     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
109         if (builtin->sessions[i] == NULL) {
110             return i;
111         }
112     }
113 
114     return -1;
115 }
116 
117 #define AES_KEYSIZE_128 16
118 #define AES_KEYSIZE_192 24
119 #define AES_KEYSIZE_256 32
120 #define AES_KEYSIZE_128_XTS AES_KEYSIZE_256
121 #define AES_KEYSIZE_256_XTS 64
122 
123 static int
124 cryptodev_builtin_get_aes_algo(uint32_t key_len, int mode, Error **errp)
125 {
126     int algo;
127 
128     if (key_len == AES_KEYSIZE_128) {
129         algo = QCRYPTO_CIPHER_ALG_AES_128;
130     } else if (key_len == AES_KEYSIZE_192) {
131         algo = QCRYPTO_CIPHER_ALG_AES_192;
132     } else if (key_len == AES_KEYSIZE_256) { /* equals AES_KEYSIZE_128_XTS */
133         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
134             algo = QCRYPTO_CIPHER_ALG_AES_128;
135         } else {
136             algo = QCRYPTO_CIPHER_ALG_AES_256;
137         }
138     } else if (key_len == AES_KEYSIZE_256_XTS) {
139         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
140             algo = QCRYPTO_CIPHER_ALG_AES_256;
141         } else {
142             goto err;
143         }
144     } else {
145         goto err;
146     }
147 
148     return algo;
149 
150 err:
151    error_setg(errp, "Unsupported key length :%u", key_len);
152    return -1;
153 }
154 
155 static int cryptodev_builtin_create_cipher_session(
156                     CryptoDevBackendBuiltin *builtin,
157                     CryptoDevBackendSymSessionInfo *sess_info,
158                     Error **errp)
159 {
160     int algo;
161     int mode;
162     QCryptoCipher *cipher;
163     int index;
164     CryptoDevBackendBuiltinSession *sess;
165 
166     if (sess_info->op_type != VIRTIO_CRYPTO_SYM_OP_CIPHER) {
167         error_setg(errp, "Unsupported optype :%u", sess_info->op_type);
168         return -1;
169     }
170 
171     index = cryptodev_builtin_get_unused_session_index(builtin);
172     if (index < 0) {
173         error_setg(errp, "Total number of sessions created exceeds %u",
174                   MAX_NUM_SESSIONS);
175         return -1;
176     }
177 
178     switch (sess_info->cipher_alg) {
179     case VIRTIO_CRYPTO_CIPHER_AES_ECB:
180         mode = QCRYPTO_CIPHER_MODE_ECB;
181         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
182                                                     mode, errp);
183         if (algo < 0)  {
184             return -1;
185         }
186         break;
187     case VIRTIO_CRYPTO_CIPHER_AES_CBC:
188         mode = QCRYPTO_CIPHER_MODE_CBC;
189         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
190                                                     mode, errp);
191         if (algo < 0)  {
192             return -1;
193         }
194         break;
195     case VIRTIO_CRYPTO_CIPHER_AES_CTR:
196         mode = QCRYPTO_CIPHER_MODE_CTR;
197         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
198                                                     mode, errp);
199         if (algo < 0)  {
200             return -1;
201         }
202         break;
203     case VIRTIO_CRYPTO_CIPHER_AES_XTS:
204         mode = QCRYPTO_CIPHER_MODE_XTS;
205         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
206                                                     mode, errp);
207         if (algo < 0)  {
208             return -1;
209         }
210         break;
211     case VIRTIO_CRYPTO_CIPHER_3DES_ECB:
212         mode = QCRYPTO_CIPHER_MODE_ECB;
213         algo = QCRYPTO_CIPHER_ALG_3DES;
214         break;
215     case VIRTIO_CRYPTO_CIPHER_3DES_CBC:
216         mode = QCRYPTO_CIPHER_MODE_CBC;
217         algo = QCRYPTO_CIPHER_ALG_3DES;
218         break;
219     case VIRTIO_CRYPTO_CIPHER_3DES_CTR:
220         mode = QCRYPTO_CIPHER_MODE_CTR;
221         algo = QCRYPTO_CIPHER_ALG_3DES;
222         break;
223     default:
224         error_setg(errp, "Unsupported cipher alg :%u",
225                    sess_info->cipher_alg);
226         return -1;
227     }
228 
229     cipher = qcrypto_cipher_new(algo, mode,
230                                sess_info->cipher_key,
231                                sess_info->key_len,
232                                errp);
233     if (!cipher) {
234         return -1;
235     }
236 
237     sess = g_new0(CryptoDevBackendBuiltinSession, 1);
238     sess->cipher = cipher;
239     sess->direction = sess_info->direction;
240     sess->type = sess_info->op_type;
241 
242     builtin->sessions[index] = sess;
243 
244     return index;
245 }
246 
247 static int64_t cryptodev_builtin_sym_create_session(
248            CryptoDevBackend *backend,
249            CryptoDevBackendSymSessionInfo *sess_info,
250            uint32_t queue_index, Error **errp)
251 {
252     CryptoDevBackendBuiltin *builtin =
253                       CRYPTODEV_BACKEND_BUILTIN(backend);
254     int64_t session_id = -1;
255     int ret;
256 
257     switch (sess_info->op_code) {
258     case VIRTIO_CRYPTO_CIPHER_CREATE_SESSION:
259         ret = cryptodev_builtin_create_cipher_session(
260                            builtin, sess_info, errp);
261         if (ret < 0) {
262             return ret;
263         } else {
264             session_id = ret;
265         }
266         break;
267     case VIRTIO_CRYPTO_HASH_CREATE_SESSION:
268     case VIRTIO_CRYPTO_MAC_CREATE_SESSION:
269     default:
270         error_setg(errp, "Unsupported opcode :%" PRIu32 "",
271                    sess_info->op_code);
272         return -1;
273     }
274 
275     return session_id;
276 }
277 
278 static int cryptodev_builtin_sym_close_session(
279            CryptoDevBackend *backend,
280            uint64_t session_id,
281            uint32_t queue_index, Error **errp)
282 {
283     CryptoDevBackendBuiltin *builtin =
284                       CRYPTODEV_BACKEND_BUILTIN(backend);
285 
286     if (session_id >= MAX_NUM_SESSIONS ||
287               builtin->sessions[session_id] == NULL) {
288         error_setg(errp, "Cannot find a valid session id: %" PRIu64 "",
289                       session_id);
290         return -1;
291     }
292 
293     qcrypto_cipher_free(builtin->sessions[session_id]->cipher);
294     g_free(builtin->sessions[session_id]);
295     builtin->sessions[session_id] = NULL;
296     return 0;
297 }
298 
299 static int cryptodev_builtin_sym_operation(
300                  CryptoDevBackend *backend,
301                  CryptoDevBackendSymOpInfo *op_info,
302                  uint32_t queue_index, Error **errp)
303 {
304     CryptoDevBackendBuiltin *builtin =
305                       CRYPTODEV_BACKEND_BUILTIN(backend);
306     CryptoDevBackendBuiltinSession *sess;
307     int ret;
308 
309     if (op_info->session_id >= MAX_NUM_SESSIONS ||
310               builtin->sessions[op_info->session_id] == NULL) {
311         error_setg(errp, "Cannot find a valid session id: %" PRIu64 "",
312                    op_info->session_id);
313         return -VIRTIO_CRYPTO_INVSESS;
314     }
315 
316     if (op_info->op_type == VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING) {
317         error_setg(errp,
318                "Algorithm chain is unsupported for cryptdoev-builtin");
319         return -VIRTIO_CRYPTO_NOTSUPP;
320     }
321 
322     sess = builtin->sessions[op_info->session_id];
323 
324     if (op_info->iv_len > 0) {
325         ret = qcrypto_cipher_setiv(sess->cipher, op_info->iv,
326                                    op_info->iv_len, errp);
327         if (ret < 0) {
328             return -VIRTIO_CRYPTO_ERR;
329         }
330     }
331 
332     if (sess->direction == VIRTIO_CRYPTO_OP_ENCRYPT) {
333         ret = qcrypto_cipher_encrypt(sess->cipher, op_info->src,
334                                      op_info->dst, op_info->src_len, errp);
335         if (ret < 0) {
336             return -VIRTIO_CRYPTO_ERR;
337         }
338     } else {
339         ret = qcrypto_cipher_decrypt(sess->cipher, op_info->src,
340                                      op_info->dst, op_info->src_len, errp);
341         if (ret < 0) {
342             return -VIRTIO_CRYPTO_ERR;
343         }
344     }
345     return VIRTIO_CRYPTO_OK;
346 }
347 
348 static void cryptodev_builtin_cleanup(
349              CryptoDevBackend *backend,
350              Error **errp)
351 {
352     CryptoDevBackendBuiltin *builtin =
353                       CRYPTODEV_BACKEND_BUILTIN(backend);
354     size_t i;
355     int queues = backend->conf.peers.queues;
356     CryptoDevBackendClient *cc;
357 
358     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
359         if (builtin->sessions[i] != NULL) {
360             cryptodev_builtin_sym_close_session(
361                     backend, i, 0, errp);
362         }
363     }
364 
365     for (i = 0; i < queues; i++) {
366         cc = backend->conf.peers.ccs[i];
367         if (cc) {
368             cryptodev_backend_free_client(cc);
369             backend->conf.peers.ccs[i] = NULL;
370         }
371     }
372 
373     cryptodev_backend_set_ready(backend, false);
374 }
375 
376 static void
377 cryptodev_builtin_class_init(ObjectClass *oc, void *data)
378 {
379     CryptoDevBackendClass *bc = CRYPTODEV_BACKEND_CLASS(oc);
380 
381     bc->init = cryptodev_builtin_init;
382     bc->cleanup = cryptodev_builtin_cleanup;
383     bc->create_session = cryptodev_builtin_sym_create_session;
384     bc->close_session = cryptodev_builtin_sym_close_session;
385     bc->do_sym_op = cryptodev_builtin_sym_operation;
386 }
387 
388 static const TypeInfo cryptodev_builtin_info = {
389     .name = TYPE_CRYPTODEV_BACKEND_BUILTIN,
390     .parent = TYPE_CRYPTODEV_BACKEND,
391     .class_init = cryptodev_builtin_class_init,
392     .instance_size = sizeof(CryptoDevBackendBuiltin),
393 };
394 
395 static void
396 cryptodev_builtin_register_types(void)
397 {
398     type_register_static(&cryptodev_builtin_info);
399 }
400 
401 type_init(cryptodev_builtin_register_types);
402