migration: force QEMUFile to blocking mode for outgoing migration
[qemu.git] / crypto / cipher-builtin.c
1 /*
2 * QEMU Crypto cipher built-in algorithms
3 *
4 * Copyright (c) 2015 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "crypto/aes.h"
23 #include "crypto/desrfb.h"
24 #include "crypto/xts.h"
25
26 typedef struct QCryptoCipherBuiltinAESContext QCryptoCipherBuiltinAESContext;
27 struct QCryptoCipherBuiltinAESContext {
28 AES_KEY enc;
29 AES_KEY dec;
30 };
31 typedef struct QCryptoCipherBuiltinAES QCryptoCipherBuiltinAES;
32 struct QCryptoCipherBuiltinAES {
33 QCryptoCipherBuiltinAESContext key;
34 QCryptoCipherBuiltinAESContext key_tweak;
35 uint8_t iv[AES_BLOCK_SIZE];
36 };
37 typedef struct QCryptoCipherBuiltinDESRFB QCryptoCipherBuiltinDESRFB;
38 struct QCryptoCipherBuiltinDESRFB {
39 uint8_t *key;
40 size_t nkey;
41 };
42
43 typedef struct QCryptoCipherBuiltin QCryptoCipherBuiltin;
44 struct QCryptoCipherBuiltin {
45 union {
46 QCryptoCipherBuiltinAES aes;
47 QCryptoCipherBuiltinDESRFB desrfb;
48 } state;
49 size_t blocksize;
50 void (*free)(QCryptoCipher *cipher);
51 int (*setiv)(QCryptoCipher *cipher,
52 const uint8_t *iv, size_t niv,
53 Error **errp);
54 int (*encrypt)(QCryptoCipher *cipher,
55 const void *in,
56 void *out,
57 size_t len,
58 Error **errp);
59 int (*decrypt)(QCryptoCipher *cipher,
60 const void *in,
61 void *out,
62 size_t len,
63 Error **errp);
64 };
65
66
67 static void qcrypto_cipher_free_aes(QCryptoCipher *cipher)
68 {
69 QCryptoCipherBuiltin *ctxt = cipher->opaque;
70
71 g_free(ctxt);
72 cipher->opaque = NULL;
73 }
74
75
76 static void qcrypto_cipher_aes_ecb_encrypt(AES_KEY *key,
77 const void *in,
78 void *out,
79 size_t len)
80 {
81 const uint8_t *inptr = in;
82 uint8_t *outptr = out;
83 while (len) {
84 if (len > AES_BLOCK_SIZE) {
85 AES_encrypt(inptr, outptr, key);
86 inptr += AES_BLOCK_SIZE;
87 outptr += AES_BLOCK_SIZE;
88 len -= AES_BLOCK_SIZE;
89 } else {
90 uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
91 memcpy(tmp1, inptr, len);
92 /* Fill with 0 to avoid valgrind uninitialized reads */
93 memset(tmp1 + len, 0, sizeof(tmp1) - len);
94 AES_encrypt(tmp1, tmp2, key);
95 memcpy(outptr, tmp2, len);
96 len = 0;
97 }
98 }
99 }
100
101
102 static void qcrypto_cipher_aes_ecb_decrypt(AES_KEY *key,
103 const void *in,
104 void *out,
105 size_t len)
106 {
107 const uint8_t *inptr = in;
108 uint8_t *outptr = out;
109 while (len) {
110 if (len > AES_BLOCK_SIZE) {
111 AES_decrypt(inptr, outptr, key);
112 inptr += AES_BLOCK_SIZE;
113 outptr += AES_BLOCK_SIZE;
114 len -= AES_BLOCK_SIZE;
115 } else {
116 uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
117 memcpy(tmp1, inptr, len);
118 /* Fill with 0 to avoid valgrind uninitialized reads */
119 memset(tmp1 + len, 0, sizeof(tmp1) - len);
120 AES_decrypt(tmp1, tmp2, key);
121 memcpy(outptr, tmp2, len);
122 len = 0;
123 }
124 }
125 }
126
127
128 static void qcrypto_cipher_aes_xts_encrypt(const void *ctx,
129 size_t length,
130 uint8_t *dst,
131 const uint8_t *src)
132 {
133 const QCryptoCipherBuiltinAESContext *aesctx = ctx;
134
135 qcrypto_cipher_aes_ecb_encrypt((AES_KEY *)&aesctx->enc,
136 src, dst, length);
137 }
138
139
140 static void qcrypto_cipher_aes_xts_decrypt(const void *ctx,
141 size_t length,
142 uint8_t *dst,
143 const uint8_t *src)
144 {
145 const QCryptoCipherBuiltinAESContext *aesctx = ctx;
146
147 qcrypto_cipher_aes_ecb_decrypt((AES_KEY *)&aesctx->dec,
148 src, dst, length);
149 }
150
151
152 static int qcrypto_cipher_encrypt_aes(QCryptoCipher *cipher,
153 const void *in,
154 void *out,
155 size_t len,
156 Error **errp)
157 {
158 QCryptoCipherBuiltin *ctxt = cipher->opaque;
159
160 switch (cipher->mode) {
161 case QCRYPTO_CIPHER_MODE_ECB:
162 qcrypto_cipher_aes_ecb_encrypt(&ctxt->state.aes.key.enc,
163 in, out, len);
164 break;
165 case QCRYPTO_CIPHER_MODE_CBC:
166 AES_cbc_encrypt(in, out, len,
167 &ctxt->state.aes.key.enc,
168 ctxt->state.aes.iv, 1);
169 break;
170 case QCRYPTO_CIPHER_MODE_XTS:
171 xts_encrypt(&ctxt->state.aes.key,
172 &ctxt->state.aes.key_tweak,
173 qcrypto_cipher_aes_xts_encrypt,
174 qcrypto_cipher_aes_xts_decrypt,
175 ctxt->state.aes.iv,
176 len, out, in);
177 break;
178 default:
179 g_assert_not_reached();
180 }
181
182 return 0;
183 }
184
185
186 static int qcrypto_cipher_decrypt_aes(QCryptoCipher *cipher,
187 const void *in,
188 void *out,
189 size_t len,
190 Error **errp)
191 {
192 QCryptoCipherBuiltin *ctxt = cipher->opaque;
193
194 switch (cipher->mode) {
195 case QCRYPTO_CIPHER_MODE_ECB:
196 qcrypto_cipher_aes_ecb_decrypt(&ctxt->state.aes.key.dec,
197 in, out, len);
198 break;
199 case QCRYPTO_CIPHER_MODE_CBC:
200 AES_cbc_encrypt(in, out, len,
201 &ctxt->state.aes.key.dec,
202 ctxt->state.aes.iv, 0);
203 break;
204 case QCRYPTO_CIPHER_MODE_XTS:
205 xts_decrypt(&ctxt->state.aes.key,
206 &ctxt->state.aes.key_tweak,
207 qcrypto_cipher_aes_xts_encrypt,
208 qcrypto_cipher_aes_xts_decrypt,
209 ctxt->state.aes.iv,
210 len, out, in);
211 break;
212 default:
213 g_assert_not_reached();
214 }
215
216 return 0;
217 }
218
219 static int qcrypto_cipher_setiv_aes(QCryptoCipher *cipher,
220 const uint8_t *iv, size_t niv,
221 Error **errp)
222 {
223 QCryptoCipherBuiltin *ctxt = cipher->opaque;
224 if (niv != AES_BLOCK_SIZE) {
225 error_setg(errp, "IV must be %d bytes not %zu",
226 AES_BLOCK_SIZE, niv);
227 return -1;
228 }
229
230 memcpy(ctxt->state.aes.iv, iv, AES_BLOCK_SIZE);
231
232 return 0;
233 }
234
235
236
237
238 static int qcrypto_cipher_init_aes(QCryptoCipher *cipher,
239 const uint8_t *key, size_t nkey,
240 Error **errp)
241 {
242 QCryptoCipherBuiltin *ctxt;
243
244 if (cipher->mode != QCRYPTO_CIPHER_MODE_CBC &&
245 cipher->mode != QCRYPTO_CIPHER_MODE_ECB &&
246 cipher->mode != QCRYPTO_CIPHER_MODE_XTS) {
247 error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
248 return -1;
249 }
250
251 ctxt = g_new0(QCryptoCipherBuiltin, 1);
252
253 if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
254 if (AES_set_encrypt_key(key, nkey * 4, &ctxt->state.aes.key.enc) != 0) {
255 error_setg(errp, "Failed to set encryption key");
256 goto error;
257 }
258
259 if (AES_set_decrypt_key(key, nkey * 4, &ctxt->state.aes.key.dec) != 0) {
260 error_setg(errp, "Failed to set decryption key");
261 goto error;
262 }
263
264 if (AES_set_encrypt_key(key + (nkey / 2), nkey * 4,
265 &ctxt->state.aes.key_tweak.enc) != 0) {
266 error_setg(errp, "Failed to set encryption key");
267 goto error;
268 }
269
270 if (AES_set_decrypt_key(key + (nkey / 2), nkey * 4,
271 &ctxt->state.aes.key_tweak.dec) != 0) {
272 error_setg(errp, "Failed to set decryption key");
273 goto error;
274 }
275 } else {
276 if (AES_set_encrypt_key(key, nkey * 8, &ctxt->state.aes.key.enc) != 0) {
277 error_setg(errp, "Failed to set encryption key");
278 goto error;
279 }
280
281 if (AES_set_decrypt_key(key, nkey * 8, &ctxt->state.aes.key.dec) != 0) {
282 error_setg(errp, "Failed to set decryption key");
283 goto error;
284 }
285 }
286
287 ctxt->blocksize = AES_BLOCK_SIZE;
288 ctxt->free = qcrypto_cipher_free_aes;
289 ctxt->setiv = qcrypto_cipher_setiv_aes;
290 ctxt->encrypt = qcrypto_cipher_encrypt_aes;
291 ctxt->decrypt = qcrypto_cipher_decrypt_aes;
292
293 cipher->opaque = ctxt;
294
295 return 0;
296
297 error:
298 g_free(ctxt);
299 return -1;
300 }
301
302
303 static void qcrypto_cipher_free_des_rfb(QCryptoCipher *cipher)
304 {
305 QCryptoCipherBuiltin *ctxt = cipher->opaque;
306
307 g_free(ctxt->state.desrfb.key);
308 g_free(ctxt);
309 cipher->opaque = NULL;
310 }
311
312
313 static int qcrypto_cipher_encrypt_des_rfb(QCryptoCipher *cipher,
314 const void *in,
315 void *out,
316 size_t len,
317 Error **errp)
318 {
319 QCryptoCipherBuiltin *ctxt = cipher->opaque;
320 size_t i;
321
322 if (len % 8) {
323 error_setg(errp, "Buffer size must be multiple of 8 not %zu",
324 len);
325 return -1;
326 }
327
328 deskey(ctxt->state.desrfb.key, EN0);
329
330 for (i = 0; i < len; i += 8) {
331 des((void *)in + i, out + i);
332 }
333
334 return 0;
335 }
336
337
338 static int qcrypto_cipher_decrypt_des_rfb(QCryptoCipher *cipher,
339 const void *in,
340 void *out,
341 size_t len,
342 Error **errp)
343 {
344 QCryptoCipherBuiltin *ctxt = cipher->opaque;
345 size_t i;
346
347 if (len % 8) {
348 error_setg(errp, "Buffer size must be multiple of 8 not %zu",
349 len);
350 return -1;
351 }
352
353 deskey(ctxt->state.desrfb.key, DE1);
354
355 for (i = 0; i < len; i += 8) {
356 des((void *)in + i, out + i);
357 }
358
359 return 0;
360 }
361
362
363 static int qcrypto_cipher_setiv_des_rfb(QCryptoCipher *cipher,
364 const uint8_t *iv, size_t niv,
365 Error **errp)
366 {
367 error_setg(errp, "Setting IV is not supported");
368 return -1;
369 }
370
371
372 static int qcrypto_cipher_init_des_rfb(QCryptoCipher *cipher,
373 const uint8_t *key, size_t nkey,
374 Error **errp)
375 {
376 QCryptoCipherBuiltin *ctxt;
377
378 if (cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
379 error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
380 return -1;
381 }
382
383 ctxt = g_new0(QCryptoCipherBuiltin, 1);
384
385 ctxt->state.desrfb.key = g_new0(uint8_t, nkey);
386 memcpy(ctxt->state.desrfb.key, key, nkey);
387 ctxt->state.desrfb.nkey = nkey;
388
389 ctxt->blocksize = 8;
390 ctxt->free = qcrypto_cipher_free_des_rfb;
391 ctxt->setiv = qcrypto_cipher_setiv_des_rfb;
392 ctxt->encrypt = qcrypto_cipher_encrypt_des_rfb;
393 ctxt->decrypt = qcrypto_cipher_decrypt_des_rfb;
394
395 cipher->opaque = ctxt;
396
397 return 0;
398 }
399
400
401 bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
402 {
403 switch (alg) {
404 case QCRYPTO_CIPHER_ALG_DES_RFB:
405 case QCRYPTO_CIPHER_ALG_AES_128:
406 case QCRYPTO_CIPHER_ALG_AES_192:
407 case QCRYPTO_CIPHER_ALG_AES_256:
408 return true;
409 default:
410 return false;
411 }
412 }
413
414
415 QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
416 QCryptoCipherMode mode,
417 const uint8_t *key, size_t nkey,
418 Error **errp)
419 {
420 QCryptoCipher *cipher;
421
422 cipher = g_new0(QCryptoCipher, 1);
423 cipher->alg = alg;
424 cipher->mode = mode;
425
426 if (!qcrypto_cipher_validate_key_length(alg, mode, nkey, errp)) {
427 goto error;
428 }
429
430 switch (cipher->alg) {
431 case QCRYPTO_CIPHER_ALG_DES_RFB:
432 if (qcrypto_cipher_init_des_rfb(cipher, key, nkey, errp) < 0) {
433 goto error;
434 }
435 break;
436 case QCRYPTO_CIPHER_ALG_AES_128:
437 case QCRYPTO_CIPHER_ALG_AES_192:
438 case QCRYPTO_CIPHER_ALG_AES_256:
439 if (qcrypto_cipher_init_aes(cipher, key, nkey, errp) < 0) {
440 goto error;
441 }
442 break;
443 default:
444 error_setg(errp,
445 "Unsupported cipher algorithm %d", cipher->alg);
446 goto error;
447 }
448
449 return cipher;
450
451 error:
452 g_free(cipher);
453 return NULL;
454 }
455
456 void qcrypto_cipher_free(QCryptoCipher *cipher)
457 {
458 QCryptoCipherBuiltin *ctxt;
459
460 if (!cipher) {
461 return;
462 }
463
464 ctxt = cipher->opaque;
465 ctxt->free(cipher);
466 g_free(cipher);
467 }
468
469
470 int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
471 const void *in,
472 void *out,
473 size_t len,
474 Error **errp)
475 {
476 QCryptoCipherBuiltin *ctxt = cipher->opaque;
477
478 if (len % ctxt->blocksize) {
479 error_setg(errp, "Length %zu must be a multiple of block size %zu",
480 len, ctxt->blocksize);
481 return -1;
482 }
483
484 return ctxt->encrypt(cipher, in, out, len, errp);
485 }
486
487
488 int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
489 const void *in,
490 void *out,
491 size_t len,
492 Error **errp)
493 {
494 QCryptoCipherBuiltin *ctxt = cipher->opaque;
495
496 if (len % ctxt->blocksize) {
497 error_setg(errp, "Length %zu must be a multiple of block size %zu",
498 len, ctxt->blocksize);
499 return -1;
500 }
501
502 return ctxt->decrypt(cipher, in, out, len, errp);
503 }
504
505
506 int qcrypto_cipher_setiv(QCryptoCipher *cipher,
507 const uint8_t *iv, size_t niv,
508 Error **errp)
509 {
510 QCryptoCipherBuiltin *ctxt = cipher->opaque;
511
512 return ctxt->setiv(cipher, iv, niv, errp);
513 }