xref: /openbmc/qemu/backends/cryptodev-builtin.c (revision 6e2e2e8a)
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 "qapi/error.h"
27 #include "standard-headers/linux/virtio_crypto.h"
28 #include "crypto/cipher.h"
29 #include "qom/object.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 OBJECT_DECLARE_SIMPLE_TYPE(CryptoDevBackendBuiltin, CRYPTODEV_BACKEND_BUILTIN)
39 
40 
41 typedef struct CryptoDevBackendBuiltinSession {
42     QCryptoCipher *cipher;
43     uint8_t direction; /* encryption or decryption */
44     uint8_t type; /* cipher? hash? aead? */
45     QTAILQ_ENTRY(CryptoDevBackendBuiltinSession) next;
46 } CryptoDevBackendBuiltinSession;
47 
48 /* Max number of symmetric sessions */
49 #define MAX_NUM_SESSIONS 256
50 
51 #define CRYPTODEV_BUITLIN_MAX_AUTH_KEY_LEN    512
52 #define CRYPTODEV_BUITLIN_MAX_CIPHER_KEY_LEN  64
53 
54 struct CryptoDevBackendBuiltin {
55     CryptoDevBackend parent_obj;
56 
57     CryptoDevBackendBuiltinSession *sessions[MAX_NUM_SESSIONS];
58 };
59 
60 static void cryptodev_builtin_init(
61              CryptoDevBackend *backend, Error **errp)
62 {
63     /* Only support one queue */
64     int queues = backend->conf.peers.queues;
65     CryptoDevBackendClient *cc;
66 
67     if (queues != 1) {
68         error_setg(errp,
69                   "Only support one queue in cryptdov-builtin backend");
70         return;
71     }
72 
73     cc = cryptodev_backend_new_client(
74               "cryptodev-builtin", NULL);
75     cc->info_str = g_strdup_printf("cryptodev-builtin0");
76     cc->queue_index = 0;
77     cc->type = CRYPTODEV_BACKEND_TYPE_BUILTIN;
78     backend->conf.peers.ccs[0] = cc;
79 
80     backend->conf.crypto_services =
81                          1u << VIRTIO_CRYPTO_SERVICE_CIPHER |
82                          1u << VIRTIO_CRYPTO_SERVICE_HASH |
83                          1u << VIRTIO_CRYPTO_SERVICE_MAC;
84     backend->conf.cipher_algo_l = 1u << VIRTIO_CRYPTO_CIPHER_AES_CBC;
85     backend->conf.hash_algo = 1u << VIRTIO_CRYPTO_HASH_SHA1;
86     /*
87      * Set the Maximum length of crypto request.
88      * Why this value? Just avoid to overflow when
89      * memory allocation for each crypto request.
90      */
91     backend->conf.max_size = LONG_MAX - sizeof(CryptoDevBackendSymOpInfo);
92     backend->conf.max_cipher_key_len = CRYPTODEV_BUITLIN_MAX_CIPHER_KEY_LEN;
93     backend->conf.max_auth_key_len = CRYPTODEV_BUITLIN_MAX_AUTH_KEY_LEN;
94 
95     cryptodev_backend_set_ready(backend, true);
96 }
97 
98 static int
99 cryptodev_builtin_get_unused_session_index(
100                  CryptoDevBackendBuiltin *builtin)
101 {
102     size_t i;
103 
104     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
105         if (builtin->sessions[i] == NULL) {
106             return i;
107         }
108     }
109 
110     return -1;
111 }
112 
113 #define AES_KEYSIZE_128 16
114 #define AES_KEYSIZE_192 24
115 #define AES_KEYSIZE_256 32
116 #define AES_KEYSIZE_128_XTS AES_KEYSIZE_256
117 #define AES_KEYSIZE_256_XTS 64
118 
119 static int
120 cryptodev_builtin_get_aes_algo(uint32_t key_len, int mode, Error **errp)
121 {
122     int algo;
123 
124     if (key_len == AES_KEYSIZE_128) {
125         algo = QCRYPTO_CIPHER_ALG_AES_128;
126     } else if (key_len == AES_KEYSIZE_192) {
127         algo = QCRYPTO_CIPHER_ALG_AES_192;
128     } else if (key_len == AES_KEYSIZE_256) { /* equals AES_KEYSIZE_128_XTS */
129         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
130             algo = QCRYPTO_CIPHER_ALG_AES_128;
131         } else {
132             algo = QCRYPTO_CIPHER_ALG_AES_256;
133         }
134     } else if (key_len == AES_KEYSIZE_256_XTS) {
135         if (mode == QCRYPTO_CIPHER_MODE_XTS) {
136             algo = QCRYPTO_CIPHER_ALG_AES_256;
137         } else {
138             goto err;
139         }
140     } else {
141         goto err;
142     }
143 
144     return algo;
145 
146 err:
147    error_setg(errp, "Unsupported key length :%u", key_len);
148    return -1;
149 }
150 
151 static int cryptodev_builtin_create_cipher_session(
152                     CryptoDevBackendBuiltin *builtin,
153                     CryptoDevBackendSymSessionInfo *sess_info,
154                     Error **errp)
155 {
156     int algo;
157     int mode;
158     QCryptoCipher *cipher;
159     int index;
160     CryptoDevBackendBuiltinSession *sess;
161 
162     if (sess_info->op_type != VIRTIO_CRYPTO_SYM_OP_CIPHER) {
163         error_setg(errp, "Unsupported optype :%u", sess_info->op_type);
164         return -1;
165     }
166 
167     index = cryptodev_builtin_get_unused_session_index(builtin);
168     if (index < 0) {
169         error_setg(errp, "Total number of sessions created exceeds %u",
170                   MAX_NUM_SESSIONS);
171         return -1;
172     }
173 
174     switch (sess_info->cipher_alg) {
175     case VIRTIO_CRYPTO_CIPHER_AES_ECB:
176         mode = QCRYPTO_CIPHER_MODE_ECB;
177         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
178                                                     mode, errp);
179         if (algo < 0)  {
180             return -1;
181         }
182         break;
183     case VIRTIO_CRYPTO_CIPHER_AES_CBC:
184         mode = QCRYPTO_CIPHER_MODE_CBC;
185         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
186                                                     mode, errp);
187         if (algo < 0)  {
188             return -1;
189         }
190         break;
191     case VIRTIO_CRYPTO_CIPHER_AES_CTR:
192         mode = QCRYPTO_CIPHER_MODE_CTR;
193         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
194                                                     mode, errp);
195         if (algo < 0)  {
196             return -1;
197         }
198         break;
199     case VIRTIO_CRYPTO_CIPHER_AES_XTS:
200         mode = QCRYPTO_CIPHER_MODE_XTS;
201         algo = cryptodev_builtin_get_aes_algo(sess_info->key_len,
202                                                     mode, errp);
203         if (algo < 0)  {
204             return -1;
205         }
206         break;
207     case VIRTIO_CRYPTO_CIPHER_3DES_ECB:
208         mode = QCRYPTO_CIPHER_MODE_ECB;
209         algo = QCRYPTO_CIPHER_ALG_3DES;
210         break;
211     case VIRTIO_CRYPTO_CIPHER_3DES_CBC:
212         mode = QCRYPTO_CIPHER_MODE_CBC;
213         algo = QCRYPTO_CIPHER_ALG_3DES;
214         break;
215     case VIRTIO_CRYPTO_CIPHER_3DES_CTR:
216         mode = QCRYPTO_CIPHER_MODE_CTR;
217         algo = QCRYPTO_CIPHER_ALG_3DES;
218         break;
219     default:
220         error_setg(errp, "Unsupported cipher alg :%u",
221                    sess_info->cipher_alg);
222         return -1;
223     }
224 
225     cipher = qcrypto_cipher_new(algo, mode,
226                                sess_info->cipher_key,
227                                sess_info->key_len,
228                                errp);
229     if (!cipher) {
230         return -1;
231     }
232 
233     sess = g_new0(CryptoDevBackendBuiltinSession, 1);
234     sess->cipher = cipher;
235     sess->direction = sess_info->direction;
236     sess->type = sess_info->op_type;
237 
238     builtin->sessions[index] = sess;
239 
240     return index;
241 }
242 
243 static int64_t cryptodev_builtin_sym_create_session(
244            CryptoDevBackend *backend,
245            CryptoDevBackendSymSessionInfo *sess_info,
246            uint32_t queue_index, Error **errp)
247 {
248     CryptoDevBackendBuiltin *builtin =
249                       CRYPTODEV_BACKEND_BUILTIN(backend);
250     int64_t session_id = -1;
251     int ret;
252 
253     switch (sess_info->op_code) {
254     case VIRTIO_CRYPTO_CIPHER_CREATE_SESSION:
255         ret = cryptodev_builtin_create_cipher_session(
256                            builtin, sess_info, errp);
257         if (ret < 0) {
258             return ret;
259         } else {
260             session_id = ret;
261         }
262         break;
263     case VIRTIO_CRYPTO_HASH_CREATE_SESSION:
264     case VIRTIO_CRYPTO_MAC_CREATE_SESSION:
265     default:
266         error_setg(errp, "Unsupported opcode :%" PRIu32 "",
267                    sess_info->op_code);
268         return -1;
269     }
270 
271     return session_id;
272 }
273 
274 static int cryptodev_builtin_sym_close_session(
275            CryptoDevBackend *backend,
276            uint64_t session_id,
277            uint32_t queue_index, Error **errp)
278 {
279     CryptoDevBackendBuiltin *builtin =
280                       CRYPTODEV_BACKEND_BUILTIN(backend);
281 
282     assert(session_id < MAX_NUM_SESSIONS && builtin->sessions[session_id]);
283 
284     qcrypto_cipher_free(builtin->sessions[session_id]->cipher);
285     g_free(builtin->sessions[session_id]);
286     builtin->sessions[session_id] = NULL;
287     return 0;
288 }
289 
290 static int cryptodev_builtin_sym_operation(
291                  CryptoDevBackend *backend,
292                  CryptoDevBackendSymOpInfo *op_info,
293                  uint32_t queue_index, Error **errp)
294 {
295     CryptoDevBackendBuiltin *builtin =
296                       CRYPTODEV_BACKEND_BUILTIN(backend);
297     CryptoDevBackendBuiltinSession *sess;
298     int ret;
299 
300     if (op_info->session_id >= MAX_NUM_SESSIONS ||
301               builtin->sessions[op_info->session_id] == NULL) {
302         error_setg(errp, "Cannot find a valid session id: %" PRIu64 "",
303                    op_info->session_id);
304         return -VIRTIO_CRYPTO_INVSESS;
305     }
306 
307     if (op_info->op_type == VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING) {
308         error_setg(errp,
309                "Algorithm chain is unsupported for cryptdoev-builtin");
310         return -VIRTIO_CRYPTO_NOTSUPP;
311     }
312 
313     sess = builtin->sessions[op_info->session_id];
314 
315     if (op_info->iv_len > 0) {
316         ret = qcrypto_cipher_setiv(sess->cipher, op_info->iv,
317                                    op_info->iv_len, errp);
318         if (ret < 0) {
319             return -VIRTIO_CRYPTO_ERR;
320         }
321     }
322 
323     if (sess->direction == VIRTIO_CRYPTO_OP_ENCRYPT) {
324         ret = qcrypto_cipher_encrypt(sess->cipher, op_info->src,
325                                      op_info->dst, op_info->src_len, errp);
326         if (ret < 0) {
327             return -VIRTIO_CRYPTO_ERR;
328         }
329     } else {
330         ret = qcrypto_cipher_decrypt(sess->cipher, op_info->src,
331                                      op_info->dst, op_info->src_len, errp);
332         if (ret < 0) {
333             return -VIRTIO_CRYPTO_ERR;
334         }
335     }
336     return VIRTIO_CRYPTO_OK;
337 }
338 
339 static void cryptodev_builtin_cleanup(
340              CryptoDevBackend *backend,
341              Error **errp)
342 {
343     CryptoDevBackendBuiltin *builtin =
344                       CRYPTODEV_BACKEND_BUILTIN(backend);
345     size_t i;
346     int queues = backend->conf.peers.queues;
347     CryptoDevBackendClient *cc;
348 
349     for (i = 0; i < MAX_NUM_SESSIONS; i++) {
350         if (builtin->sessions[i] != NULL) {
351             cryptodev_builtin_sym_close_session(backend, i, 0, &error_abort);
352         }
353     }
354 
355     for (i = 0; i < queues; i++) {
356         cc = backend->conf.peers.ccs[i];
357         if (cc) {
358             cryptodev_backend_free_client(cc);
359             backend->conf.peers.ccs[i] = NULL;
360         }
361     }
362 
363     cryptodev_backend_set_ready(backend, false);
364 }
365 
366 static void
367 cryptodev_builtin_class_init(ObjectClass *oc, void *data)
368 {
369     CryptoDevBackendClass *bc = CRYPTODEV_BACKEND_CLASS(oc);
370 
371     bc->init = cryptodev_builtin_init;
372     bc->cleanup = cryptodev_builtin_cleanup;
373     bc->create_session = cryptodev_builtin_sym_create_session;
374     bc->close_session = cryptodev_builtin_sym_close_session;
375     bc->do_sym_op = cryptodev_builtin_sym_operation;
376 }
377 
378 static const TypeInfo cryptodev_builtin_info = {
379     .name = TYPE_CRYPTODEV_BACKEND_BUILTIN,
380     .parent = TYPE_CRYPTODEV_BACKEND,
381     .class_init = cryptodev_builtin_class_init,
382     .instance_size = sizeof(CryptoDevBackendBuiltin),
383 };
384 
385 static void
386 cryptodev_builtin_register_types(void)
387 {
388     type_register_static(&cryptodev_builtin_info);
389 }
390 
391 type_init(cryptodev_builtin_register_types);
392