xref: /openbmc/linux/crypto/simd.c (revision f5ad1c74) 
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Shared crypto simd helpers
4  *
5  * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
6  * Copyright (c) 2016 Herbert Xu <herbert@gondor.apana.org.au>
7  * Copyright (c) 2019 Google LLC
8  *
9  * Based on aesni-intel_glue.c by:
10  *  Copyright (C) 2008, Intel Corp.
11  *    Author: Huang Ying <ying.huang@intel.com>
12  */
13 
14 /*
15  * Shared crypto SIMD helpers.  These functions dynamically create and register
16  * an skcipher or AEAD algorithm that wraps another, internal algorithm.  The
17  * wrapper ensures that the internal algorithm is only executed in a context
18  * where SIMD instructions are usable, i.e. where may_use_simd() returns true.
19  * If SIMD is already usable, the wrapper directly calls the internal algorithm.
20  * Otherwise it defers execution to a workqueue via cryptd.
21  *
22  * This is an alternative to the internal algorithm implementing a fallback for
23  * the !may_use_simd() case itself.
24  *
25  * Note that the wrapper algorithm is asynchronous, i.e. it has the
26  * CRYPTO_ALG_ASYNC flag set.  Therefore it won't be found by users who
27  * explicitly allocate a synchronous algorithm.
28  */
29 
30 #include <crypto/cryptd.h>
31 #include <crypto/internal/aead.h>
32 #include <crypto/internal/simd.h>
33 #include <crypto/internal/skcipher.h>
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/preempt.h>
37 #include <asm/simd.h>
38 
39 /* skcipher support */
40 
41 struct simd_skcipher_alg {
42 	const char *ialg_name;
43 	struct skcipher_alg alg;
44 };
45 
46 struct simd_skcipher_ctx {
47 	struct cryptd_skcipher *cryptd_tfm;
48 };
49 
50 static int simd_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
51 				unsigned int key_len)
52 {
53 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
54 	struct crypto_skcipher *child = &ctx->cryptd_tfm->base;
55 
56 	crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
57 	crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(tfm) &
58 					 CRYPTO_TFM_REQ_MASK);
59 	return crypto_skcipher_setkey(child, key, key_len);
60 }
61 
62 static int simd_skcipher_encrypt(struct skcipher_request *req)
63 {
64 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
65 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
66 	struct skcipher_request *subreq;
67 	struct crypto_skcipher *child;
68 
69 	subreq = skcipher_request_ctx(req);
70 	*subreq = *req;
71 
72 	if (!crypto_simd_usable() ||
73 	    (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
74 		child = &ctx->cryptd_tfm->base;
75 	else
76 		child = cryptd_skcipher_child(ctx->cryptd_tfm);
77 
78 	skcipher_request_set_tfm(subreq, child);
79 
80 	return crypto_skcipher_encrypt(subreq);
81 }
82 
83 static int simd_skcipher_decrypt(struct skcipher_request *req)
84 {
85 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
86 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
87 	struct skcipher_request *subreq;
88 	struct crypto_skcipher *child;
89 
90 	subreq = skcipher_request_ctx(req);
91 	*subreq = *req;
92 
93 	if (!crypto_simd_usable() ||
94 	    (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
95 		child = &ctx->cryptd_tfm->base;
96 	else
97 		child = cryptd_skcipher_child(ctx->cryptd_tfm);
98 
99 	skcipher_request_set_tfm(subreq, child);
100 
101 	return crypto_skcipher_decrypt(subreq);
102 }
103 
104 static void simd_skcipher_exit(struct crypto_skcipher *tfm)
105 {
106 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
107 
108 	cryptd_free_skcipher(ctx->cryptd_tfm);
109 }
110 
111 static int simd_skcipher_init(struct crypto_skcipher *tfm)
112 {
113 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
114 	struct cryptd_skcipher *cryptd_tfm;
115 	struct simd_skcipher_alg *salg;
116 	struct skcipher_alg *alg;
117 	unsigned reqsize;
118 
119 	alg = crypto_skcipher_alg(tfm);
120 	salg = container_of(alg, struct simd_skcipher_alg, alg);
121 
122 	cryptd_tfm = cryptd_alloc_skcipher(salg->ialg_name,
123 					   CRYPTO_ALG_INTERNAL,
124 					   CRYPTO_ALG_INTERNAL);
125 	if (IS_ERR(cryptd_tfm))
126 		return PTR_ERR(cryptd_tfm);
127 
128 	ctx->cryptd_tfm = cryptd_tfm;
129 
130 	reqsize = crypto_skcipher_reqsize(cryptd_skcipher_child(cryptd_tfm));
131 	reqsize = max(reqsize, crypto_skcipher_reqsize(&cryptd_tfm->base));
132 	reqsize += sizeof(struct skcipher_request);
133 
134 	crypto_skcipher_set_reqsize(tfm, reqsize);
135 
136 	return 0;
137 }
138 
139 struct simd_skcipher_alg *simd_skcipher_create_compat(const char *algname,
140 						      const char *drvname,
141 						      const char *basename)
142 {
143 	struct simd_skcipher_alg *salg;
144 	struct crypto_skcipher *tfm;
145 	struct skcipher_alg *ialg;
146 	struct skcipher_alg *alg;
147 	int err;
148 
149 	tfm = crypto_alloc_skcipher(basename, CRYPTO_ALG_INTERNAL,
150 				    CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
151 	if (IS_ERR(tfm))
152 		return ERR_CAST(tfm);
153 
154 	ialg = crypto_skcipher_alg(tfm);
155 
156 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
157 	if (!salg) {
158 		salg = ERR_PTR(-ENOMEM);
159 		goto out_put_tfm;
160 	}
161 
162 	salg->ialg_name = basename;
163 	alg = &salg->alg;
164 
165 	err = -ENAMETOOLONG;
166 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
167 	    CRYPTO_MAX_ALG_NAME)
168 		goto out_free_salg;
169 
170 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
171 		     drvname) >= CRYPTO_MAX_ALG_NAME)
172 		goto out_free_salg;
173 
174 	alg->base.cra_flags = CRYPTO_ALG_ASYNC |
175 		(ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
176 	alg->base.cra_priority = ialg->base.cra_priority;
177 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
178 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
179 	alg->base.cra_module = ialg->base.cra_module;
180 	alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
181 
182 	alg->ivsize = ialg->ivsize;
183 	alg->chunksize = ialg->chunksize;
184 	alg->min_keysize = ialg->min_keysize;
185 	alg->max_keysize = ialg->max_keysize;
186 
187 	alg->init = simd_skcipher_init;
188 	alg->exit = simd_skcipher_exit;
189 
190 	alg->setkey = simd_skcipher_setkey;
191 	alg->encrypt = simd_skcipher_encrypt;
192 	alg->decrypt = simd_skcipher_decrypt;
193 
194 	err = crypto_register_skcipher(alg);
195 	if (err)
196 		goto out_free_salg;
197 
198 out_put_tfm:
199 	crypto_free_skcipher(tfm);
200 	return salg;
201 
202 out_free_salg:
203 	kfree(salg);
204 	salg = ERR_PTR(err);
205 	goto out_put_tfm;
206 }
207 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
208 
209 struct simd_skcipher_alg *simd_skcipher_create(const char *algname,
210 					       const char *basename)
211 {
212 	char drvname[CRYPTO_MAX_ALG_NAME];
213 
214 	if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
215 	    CRYPTO_MAX_ALG_NAME)
216 		return ERR_PTR(-ENAMETOOLONG);
217 
218 	return simd_skcipher_create_compat(algname, drvname, basename);
219 }
220 EXPORT_SYMBOL_GPL(simd_skcipher_create);
221 
222 void simd_skcipher_free(struct simd_skcipher_alg *salg)
223 {
224 	crypto_unregister_skcipher(&salg->alg);
225 	kfree(salg);
226 }
227 EXPORT_SYMBOL_GPL(simd_skcipher_free);
228 
229 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
230 				   struct simd_skcipher_alg **simd_algs)
231 {
232 	int err;
233 	int i;
234 	const char *algname;
235 	const char *drvname;
236 	const char *basename;
237 	struct simd_skcipher_alg *simd;
238 
239 	err = crypto_register_skciphers(algs, count);
240 	if (err)
241 		return err;
242 
243 	for (i = 0; i < count; i++) {
244 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
245 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
246 		algname = algs[i].base.cra_name + 2;
247 		drvname = algs[i].base.cra_driver_name + 2;
248 		basename = algs[i].base.cra_driver_name;
249 		simd = simd_skcipher_create_compat(algname, drvname, basename);
250 		err = PTR_ERR(simd);
251 		if (IS_ERR(simd))
252 			goto err_unregister;
253 		simd_algs[i] = simd;
254 	}
255 	return 0;
256 
257 err_unregister:
258 	simd_unregister_skciphers(algs, count, simd_algs);
259 	return err;
260 }
261 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
262 
263 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
264 			       struct simd_skcipher_alg **simd_algs)
265 {
266 	int i;
267 
268 	crypto_unregister_skciphers(algs, count);
269 
270 	for (i = 0; i < count; i++) {
271 		if (simd_algs[i]) {
272 			simd_skcipher_free(simd_algs[i]);
273 			simd_algs[i] = NULL;
274 		}
275 	}
276 }
277 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
278 
279 /* AEAD support */
280 
281 struct simd_aead_alg {
282 	const char *ialg_name;
283 	struct aead_alg alg;
284 };
285 
286 struct simd_aead_ctx {
287 	struct cryptd_aead *cryptd_tfm;
288 };
289 
290 static int simd_aead_setkey(struct crypto_aead *tfm, const u8 *key,
291 				unsigned int key_len)
292 {
293 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
294 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
295 
296 	crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
297 	crypto_aead_set_flags(child, crypto_aead_get_flags(tfm) &
298 				     CRYPTO_TFM_REQ_MASK);
299 	return crypto_aead_setkey(child, key, key_len);
300 }
301 
302 static int simd_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
303 {
304 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
305 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
306 
307 	return crypto_aead_setauthsize(child, authsize);
308 }
309 
310 static int simd_aead_encrypt(struct aead_request *req)
311 {
312 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
313 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
314 	struct aead_request *subreq;
315 	struct crypto_aead *child;
316 
317 	subreq = aead_request_ctx(req);
318 	*subreq = *req;
319 
320 	if (!crypto_simd_usable() ||
321 	    (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
322 		child = &ctx->cryptd_tfm->base;
323 	else
324 		child = cryptd_aead_child(ctx->cryptd_tfm);
325 
326 	aead_request_set_tfm(subreq, child);
327 
328 	return crypto_aead_encrypt(subreq);
329 }
330 
331 static int simd_aead_decrypt(struct aead_request *req)
332 {
333 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
334 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
335 	struct aead_request *subreq;
336 	struct crypto_aead *child;
337 
338 	subreq = aead_request_ctx(req);
339 	*subreq = *req;
340 
341 	if (!crypto_simd_usable() ||
342 	    (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
343 		child = &ctx->cryptd_tfm->base;
344 	else
345 		child = cryptd_aead_child(ctx->cryptd_tfm);
346 
347 	aead_request_set_tfm(subreq, child);
348 
349 	return crypto_aead_decrypt(subreq);
350 }
351 
352 static void simd_aead_exit(struct crypto_aead *tfm)
353 {
354 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
355 
356 	cryptd_free_aead(ctx->cryptd_tfm);
357 }
358 
359 static int simd_aead_init(struct crypto_aead *tfm)
360 {
361 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
362 	struct cryptd_aead *cryptd_tfm;
363 	struct simd_aead_alg *salg;
364 	struct aead_alg *alg;
365 	unsigned reqsize;
366 
367 	alg = crypto_aead_alg(tfm);
368 	salg = container_of(alg, struct simd_aead_alg, alg);
369 
370 	cryptd_tfm = cryptd_alloc_aead(salg->ialg_name, CRYPTO_ALG_INTERNAL,
371 				       CRYPTO_ALG_INTERNAL);
372 	if (IS_ERR(cryptd_tfm))
373 		return PTR_ERR(cryptd_tfm);
374 
375 	ctx->cryptd_tfm = cryptd_tfm;
376 
377 	reqsize = crypto_aead_reqsize(cryptd_aead_child(cryptd_tfm));
378 	reqsize = max(reqsize, crypto_aead_reqsize(&cryptd_tfm->base));
379 	reqsize += sizeof(struct aead_request);
380 
381 	crypto_aead_set_reqsize(tfm, reqsize);
382 
383 	return 0;
384 }
385 
386 struct simd_aead_alg *simd_aead_create_compat(const char *algname,
387 					      const char *drvname,
388 					      const char *basename)
389 {
390 	struct simd_aead_alg *salg;
391 	struct crypto_aead *tfm;
392 	struct aead_alg *ialg;
393 	struct aead_alg *alg;
394 	int err;
395 
396 	tfm = crypto_alloc_aead(basename, CRYPTO_ALG_INTERNAL,
397 				CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
398 	if (IS_ERR(tfm))
399 		return ERR_CAST(tfm);
400 
401 	ialg = crypto_aead_alg(tfm);
402 
403 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
404 	if (!salg) {
405 		salg = ERR_PTR(-ENOMEM);
406 		goto out_put_tfm;
407 	}
408 
409 	salg->ialg_name = basename;
410 	alg = &salg->alg;
411 
412 	err = -ENAMETOOLONG;
413 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
414 	    CRYPTO_MAX_ALG_NAME)
415 		goto out_free_salg;
416 
417 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
418 		     drvname) >= CRYPTO_MAX_ALG_NAME)
419 		goto out_free_salg;
420 
421 	alg->base.cra_flags = CRYPTO_ALG_ASYNC |
422 		(ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
423 	alg->base.cra_priority = ialg->base.cra_priority;
424 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
425 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
426 	alg->base.cra_module = ialg->base.cra_module;
427 	alg->base.cra_ctxsize = sizeof(struct simd_aead_ctx);
428 
429 	alg->ivsize = ialg->ivsize;
430 	alg->maxauthsize = ialg->maxauthsize;
431 	alg->chunksize = ialg->chunksize;
432 
433 	alg->init = simd_aead_init;
434 	alg->exit = simd_aead_exit;
435 
436 	alg->setkey = simd_aead_setkey;
437 	alg->setauthsize = simd_aead_setauthsize;
438 	alg->encrypt = simd_aead_encrypt;
439 	alg->decrypt = simd_aead_decrypt;
440 
441 	err = crypto_register_aead(alg);
442 	if (err)
443 		goto out_free_salg;
444 
445 out_put_tfm:
446 	crypto_free_aead(tfm);
447 	return salg;
448 
449 out_free_salg:
450 	kfree(salg);
451 	salg = ERR_PTR(err);
452 	goto out_put_tfm;
453 }
454 EXPORT_SYMBOL_GPL(simd_aead_create_compat);
455 
456 struct simd_aead_alg *simd_aead_create(const char *algname,
457 				       const char *basename)
458 {
459 	char drvname[CRYPTO_MAX_ALG_NAME];
460 
461 	if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
462 	    CRYPTO_MAX_ALG_NAME)
463 		return ERR_PTR(-ENAMETOOLONG);
464 
465 	return simd_aead_create_compat(algname, drvname, basename);
466 }
467 EXPORT_SYMBOL_GPL(simd_aead_create);
468 
469 void simd_aead_free(struct simd_aead_alg *salg)
470 {
471 	crypto_unregister_aead(&salg->alg);
472 	kfree(salg);
473 }
474 EXPORT_SYMBOL_GPL(simd_aead_free);
475 
476 int simd_register_aeads_compat(struct aead_alg *algs, int count,
477 			       struct simd_aead_alg **simd_algs)
478 {
479 	int err;
480 	int i;
481 	const char *algname;
482 	const char *drvname;
483 	const char *basename;
484 	struct simd_aead_alg *simd;
485 
486 	err = crypto_register_aeads(algs, count);
487 	if (err)
488 		return err;
489 
490 	for (i = 0; i < count; i++) {
491 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
492 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
493 		algname = algs[i].base.cra_name + 2;
494 		drvname = algs[i].base.cra_driver_name + 2;
495 		basename = algs[i].base.cra_driver_name;
496 		simd = simd_aead_create_compat(algname, drvname, basename);
497 		err = PTR_ERR(simd);
498 		if (IS_ERR(simd))
499 			goto err_unregister;
500 		simd_algs[i] = simd;
501 	}
502 	return 0;
503 
504 err_unregister:
505 	simd_unregister_aeads(algs, count, simd_algs);
506 	return err;
507 }
508 EXPORT_SYMBOL_GPL(simd_register_aeads_compat);
509 
510 void simd_unregister_aeads(struct aead_alg *algs, int count,
511 			   struct simd_aead_alg **simd_algs)
512 {
513 	int i;
514 
515 	crypto_unregister_aeads(algs, count);
516 
517 	for (i = 0; i < count; i++) {
518 		if (simd_algs[i]) {
519 			simd_aead_free(simd_algs[i]);
520 			simd_algs[i] = NULL;
521 		}
522 	}
523 }
524 EXPORT_SYMBOL_GPL(simd_unregister_aeads);
525 
526 MODULE_LICENSE("GPL");
527