Merge remote-tracking branch 'remotes/kraxel/tags/pull-vga-20170103-1' into staging
[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 %s",
248 QCryptoCipherMode_lookup[cipher->mode]);
249 return -1;
250 }
251
252 ctxt = g_new0(QCryptoCipherBuiltin, 1);
253
254 if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
255 if (AES_set_encrypt_key(key, nkey * 4, &ctxt->state.aes.key.enc) != 0) {
256 error_setg(errp, "Failed to set encryption key");
257 goto error;
258 }
259
260 if (AES_set_decrypt_key(key, nkey * 4, &ctxt->state.aes.key.dec) != 0) {
261 error_setg(errp, "Failed to set decryption key");
262 goto error;
263 }
264
265 if (AES_set_encrypt_key(key + (nkey / 2), nkey * 4,
266 &ctxt->state.aes.key_tweak.enc) != 0) {
267 error_setg(errp, "Failed to set encryption key");
268 goto error;
269 }
270
271 if (AES_set_decrypt_key(key + (nkey / 2), nkey * 4,
272 &ctxt->state.aes.key_tweak.dec) != 0) {
273 error_setg(errp, "Failed to set decryption key");
274 goto error;
275 }
276 } else {
277 if (AES_set_encrypt_key(key, nkey * 8, &ctxt->state.aes.key.enc) != 0) {
278 error_setg(errp, "Failed to set encryption key");
279 goto error;
280 }
281
282 if (AES_set_decrypt_key(key, nkey * 8, &ctxt->state.aes.key.dec) != 0) {
283 error_setg(errp, "Failed to set decryption key");
284 goto error;
285 }
286 }
287
288 ctxt->blocksize = AES_BLOCK_SIZE;
289 ctxt->free = qcrypto_cipher_free_aes;
290 ctxt->setiv = qcrypto_cipher_setiv_aes;
291 ctxt->encrypt = qcrypto_cipher_encrypt_aes;
292 ctxt->decrypt = qcrypto_cipher_decrypt_aes;
293
294 cipher->opaque = ctxt;
295
296 return 0;
297
298 error:
299 g_free(ctxt);
300 return -1;
301 }
302
303
304 static void qcrypto_cipher_free_des_rfb(QCryptoCipher *cipher)
305 {
306 QCryptoCipherBuiltin *ctxt = cipher->opaque;
307
308 g_free(ctxt->state.desrfb.key);
309 g_free(ctxt);
310 cipher->opaque = NULL;
311 }
312
313
314 static int qcrypto_cipher_encrypt_des_rfb(QCryptoCipher *cipher,
315 const void *in,
316 void *out,
317 size_t len,
318 Error **errp)
319 {
320 QCryptoCipherBuiltin *ctxt = cipher->opaque;
321 size_t i;
322
323 if (len % 8) {
324 error_setg(errp, "Buffer size must be multiple of 8 not %zu",
325 len);
326 return -1;
327 }
328
329 deskey(ctxt->state.desrfb.key, EN0);
330
331 for (i = 0; i < len; i += 8) {
332 des((void *)in + i, out + i);
333 }
334
335 return 0;
336 }
337
338
339 static int qcrypto_cipher_decrypt_des_rfb(QCryptoCipher *cipher,
340 const void *in,
341 void *out,
342 size_t len,
343 Error **errp)
344 {
345 QCryptoCipherBuiltin *ctxt = cipher->opaque;
346 size_t i;
347
348 if (len % 8) {
349 error_setg(errp, "Buffer size must be multiple of 8 not %zu",
350 len);
351 return -1;
352 }
353
354 deskey(ctxt->state.desrfb.key, DE1);
355
356 for (i = 0; i < len; i += 8) {
357 des((void *)in + i, out + i);
358 }
359
360 return 0;
361 }
362
363
364 static int qcrypto_cipher_setiv_des_rfb(QCryptoCipher *cipher,
365 const uint8_t *iv, size_t niv,
366 Error **errp)
367 {
368 error_setg(errp, "Setting IV is not supported");
369 return -1;
370 }
371
372
373 static int qcrypto_cipher_init_des_rfb(QCryptoCipher *cipher,
374 const uint8_t *key, size_t nkey,
375 Error **errp)
376 {
377 QCryptoCipherBuiltin *ctxt;
378
379 if (cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
380 error_setg(errp, "Unsupported cipher mode %s",
381 QCryptoCipherMode_lookup[cipher->mode]);
382 return -1;
383 }
384
385 ctxt = g_new0(QCryptoCipherBuiltin, 1);
386
387 ctxt->state.desrfb.key = g_new0(uint8_t, nkey);
388 memcpy(ctxt->state.desrfb.key, key, nkey);
389 ctxt->state.desrfb.nkey = nkey;
390
391 ctxt->blocksize = 8;
392 ctxt->free = qcrypto_cipher_free_des_rfb;
393 ctxt->setiv = qcrypto_cipher_setiv_des_rfb;
394 ctxt->encrypt = qcrypto_cipher_encrypt_des_rfb;
395 ctxt->decrypt = qcrypto_cipher_decrypt_des_rfb;
396
397 cipher->opaque = ctxt;
398
399 return 0;
400 }
401
402
403 bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg,
404 QCryptoCipherMode mode)
405 {
406 switch (alg) {
407 case QCRYPTO_CIPHER_ALG_DES_RFB:
408 case QCRYPTO_CIPHER_ALG_AES_128:
409 case QCRYPTO_CIPHER_ALG_AES_192:
410 case QCRYPTO_CIPHER_ALG_AES_256:
411 break;
412 default:
413 return false;
414 }
415
416 switch (mode) {
417 case QCRYPTO_CIPHER_MODE_ECB:
418 case QCRYPTO_CIPHER_MODE_CBC:
419 case QCRYPTO_CIPHER_MODE_XTS:
420 return true;
421 case QCRYPTO_CIPHER_MODE_CTR:
422 return false;
423 default:
424 return false;
425 }
426 }
427
428
429 QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
430 QCryptoCipherMode mode,
431 const uint8_t *key, size_t nkey,
432 Error **errp)
433 {
434 QCryptoCipher *cipher;
435
436 switch (mode) {
437 case QCRYPTO_CIPHER_MODE_ECB:
438 case QCRYPTO_CIPHER_MODE_CBC:
439 case QCRYPTO_CIPHER_MODE_XTS:
440 break;
441 default:
442 error_setg(errp, "Unsupported cipher mode %s",
443 QCryptoCipherMode_lookup[mode]);
444 return NULL;
445 }
446
447 cipher = g_new0(QCryptoCipher, 1);
448 cipher->alg = alg;
449 cipher->mode = mode;
450
451 if (!qcrypto_cipher_validate_key_length(alg, mode, nkey, errp)) {
452 goto error;
453 }
454
455 switch (cipher->alg) {
456 case QCRYPTO_CIPHER_ALG_DES_RFB:
457 if (qcrypto_cipher_init_des_rfb(cipher, key, nkey, errp) < 0) {
458 goto error;
459 }
460 break;
461 case QCRYPTO_CIPHER_ALG_AES_128:
462 case QCRYPTO_CIPHER_ALG_AES_192:
463 case QCRYPTO_CIPHER_ALG_AES_256:
464 if (qcrypto_cipher_init_aes(cipher, key, nkey, errp) < 0) {
465 goto error;
466 }
467 break;
468 default:
469 error_setg(errp,
470 "Unsupported cipher algorithm %s",
471 QCryptoCipherAlgorithm_lookup[cipher->alg]);
472 goto error;
473 }
474
475 return cipher;
476
477 error:
478 g_free(cipher);
479 return NULL;
480 }
481
482 void qcrypto_cipher_free(QCryptoCipher *cipher)
483 {
484 QCryptoCipherBuiltin *ctxt;
485
486 if (!cipher) {
487 return;
488 }
489
490 ctxt = cipher->opaque;
491 ctxt->free(cipher);
492 g_free(cipher);
493 }
494
495
496 int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
497 const void *in,
498 void *out,
499 size_t len,
500 Error **errp)
501 {
502 QCryptoCipherBuiltin *ctxt = cipher->opaque;
503
504 if (len % ctxt->blocksize) {
505 error_setg(errp, "Length %zu must be a multiple of block size %zu",
506 len, ctxt->blocksize);
507 return -1;
508 }
509
510 return ctxt->encrypt(cipher, in, out, len, errp);
511 }
512
513
514 int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
515 const void *in,
516 void *out,
517 size_t len,
518 Error **errp)
519 {
520 QCryptoCipherBuiltin *ctxt = cipher->opaque;
521
522 if (len % ctxt->blocksize) {
523 error_setg(errp, "Length %zu must be a multiple of block size %zu",
524 len, ctxt->blocksize);
525 return -1;
526 }
527
528 return ctxt->decrypt(cipher, in, out, len, errp);
529 }
530
531
532 int qcrypto_cipher_setiv(QCryptoCipher *cipher,
533 const uint8_t *iv, size_t niv,
534 Error **errp)
535 {
536 QCryptoCipherBuiltin *ctxt = cipher->opaque;
537
538 return ctxt->setiv(cipher, iv, niv, errp);
539 }