xref: /openbmc/linux/crypto/simd.c (revision fb574682) 
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 	alg->base.cra_priority = ialg->base.cra_priority;
176 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
177 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
178 	alg->base.cra_module = ialg->base.cra_module;
179 	alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
180 
181 	alg->ivsize = ialg->ivsize;
182 	alg->chunksize = ialg->chunksize;
183 	alg->min_keysize = ialg->min_keysize;
184 	alg->max_keysize = ialg->max_keysize;
185 
186 	alg->init = simd_skcipher_init;
187 	alg->exit = simd_skcipher_exit;
188 
189 	alg->setkey = simd_skcipher_setkey;
190 	alg->encrypt = simd_skcipher_encrypt;
191 	alg->decrypt = simd_skcipher_decrypt;
192 
193 	err = crypto_register_skcipher(alg);
194 	if (err)
195 		goto out_free_salg;
196 
197 out_put_tfm:
198 	crypto_free_skcipher(tfm);
199 	return salg;
200 
201 out_free_salg:
202 	kfree(salg);
203 	salg = ERR_PTR(err);
204 	goto out_put_tfm;
205 }
206 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
207 
208 struct simd_skcipher_alg *simd_skcipher_create(const char *algname,
209 					       const char *basename)
210 {
211 	char drvname[CRYPTO_MAX_ALG_NAME];
212 
213 	if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
214 	    CRYPTO_MAX_ALG_NAME)
215 		return ERR_PTR(-ENAMETOOLONG);
216 
217 	return simd_skcipher_create_compat(algname, drvname, basename);
218 }
219 EXPORT_SYMBOL_GPL(simd_skcipher_create);
220 
221 void simd_skcipher_free(struct simd_skcipher_alg *salg)
222 {
223 	crypto_unregister_skcipher(&salg->alg);
224 	kfree(salg);
225 }
226 EXPORT_SYMBOL_GPL(simd_skcipher_free);
227 
228 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
229 				   struct simd_skcipher_alg **simd_algs)
230 {
231 	int err;
232 	int i;
233 	const char *algname;
234 	const char *drvname;
235 	const char *basename;
236 	struct simd_skcipher_alg *simd;
237 
238 	err = crypto_register_skciphers(algs, count);
239 	if (err)
240 		return err;
241 
242 	for (i = 0; i < count; i++) {
243 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
244 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
245 		algname = algs[i].base.cra_name + 2;
246 		drvname = algs[i].base.cra_driver_name + 2;
247 		basename = algs[i].base.cra_driver_name;
248 		simd = simd_skcipher_create_compat(algname, drvname, basename);
249 		err = PTR_ERR(simd);
250 		if (IS_ERR(simd))
251 			goto err_unregister;
252 		simd_algs[i] = simd;
253 	}
254 	return 0;
255 
256 err_unregister:
257 	simd_unregister_skciphers(algs, count, simd_algs);
258 	return err;
259 }
260 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
261 
262 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
263 			       struct simd_skcipher_alg **simd_algs)
264 {
265 	int i;
266 
267 	crypto_unregister_skciphers(algs, count);
268 
269 	for (i = 0; i < count; i++) {
270 		if (simd_algs[i]) {
271 			simd_skcipher_free(simd_algs[i]);
272 			simd_algs[i] = NULL;
273 		}
274 	}
275 }
276 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
277 
278 /* AEAD support */
279 
280 struct simd_aead_alg {
281 	const char *ialg_name;
282 	struct aead_alg alg;
283 };
284 
285 struct simd_aead_ctx {
286 	struct cryptd_aead *cryptd_tfm;
287 };
288 
289 static int simd_aead_setkey(struct crypto_aead *tfm, const u8 *key,
290 				unsigned int key_len)
291 {
292 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
293 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
294 
295 	crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
296 	crypto_aead_set_flags(child, crypto_aead_get_flags(tfm) &
297 				     CRYPTO_TFM_REQ_MASK);
298 	return crypto_aead_setkey(child, key, key_len);
299 }
300 
301 static int simd_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
302 {
303 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
304 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
305 
306 	return crypto_aead_setauthsize(child, authsize);
307 }
308 
309 static int simd_aead_encrypt(struct aead_request *req)
310 {
311 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
312 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
313 	struct aead_request *subreq;
314 	struct crypto_aead *child;
315 
316 	subreq = aead_request_ctx(req);
317 	*subreq = *req;
318 
319 	if (!crypto_simd_usable() ||
320 	    (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
321 		child = &ctx->cryptd_tfm->base;
322 	else
323 		child = cryptd_aead_child(ctx->cryptd_tfm);
324 
325 	aead_request_set_tfm(subreq, child);
326 
327 	return crypto_aead_encrypt(subreq);
328 }
329 
330 static int simd_aead_decrypt(struct aead_request *req)
331 {
332 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
333 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
334 	struct aead_request *subreq;
335 	struct crypto_aead *child;
336 
337 	subreq = aead_request_ctx(req);
338 	*subreq = *req;
339 
340 	if (!crypto_simd_usable() ||
341 	    (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
342 		child = &ctx->cryptd_tfm->base;
343 	else
344 		child = cryptd_aead_child(ctx->cryptd_tfm);
345 
346 	aead_request_set_tfm(subreq, child);
347 
348 	return crypto_aead_decrypt(subreq);
349 }
350 
351 static void simd_aead_exit(struct crypto_aead *tfm)
352 {
353 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
354 
355 	cryptd_free_aead(ctx->cryptd_tfm);
356 }
357 
358 static int simd_aead_init(struct crypto_aead *tfm)
359 {
360 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
361 	struct cryptd_aead *cryptd_tfm;
362 	struct simd_aead_alg *salg;
363 	struct aead_alg *alg;
364 	unsigned reqsize;
365 
366 	alg = crypto_aead_alg(tfm);
367 	salg = container_of(alg, struct simd_aead_alg, alg);
368 
369 	cryptd_tfm = cryptd_alloc_aead(salg->ialg_name, CRYPTO_ALG_INTERNAL,
370 				       CRYPTO_ALG_INTERNAL);
371 	if (IS_ERR(cryptd_tfm))
372 		return PTR_ERR(cryptd_tfm);
373 
374 	ctx->cryptd_tfm = cryptd_tfm;
375 
376 	reqsize = crypto_aead_reqsize(cryptd_aead_child(cryptd_tfm));
377 	reqsize = max(reqsize, crypto_aead_reqsize(&cryptd_tfm->base));
378 	reqsize += sizeof(struct aead_request);
379 
380 	crypto_aead_set_reqsize(tfm, reqsize);
381 
382 	return 0;
383 }
384 
385 struct simd_aead_alg *simd_aead_create_compat(const char *algname,
386 					      const char *drvname,
387 					      const char *basename)
388 {
389 	struct simd_aead_alg *salg;
390 	struct crypto_aead *tfm;
391 	struct aead_alg *ialg;
392 	struct aead_alg *alg;
393 	int err;
394 
395 	tfm = crypto_alloc_aead(basename, CRYPTO_ALG_INTERNAL,
396 				CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
397 	if (IS_ERR(tfm))
398 		return ERR_CAST(tfm);
399 
400 	ialg = crypto_aead_alg(tfm);
401 
402 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
403 	if (!salg) {
404 		salg = ERR_PTR(-ENOMEM);
405 		goto out_put_tfm;
406 	}
407 
408 	salg->ialg_name = basename;
409 	alg = &salg->alg;
410 
411 	err = -ENAMETOOLONG;
412 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
413 	    CRYPTO_MAX_ALG_NAME)
414 		goto out_free_salg;
415 
416 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
417 		     drvname) >= CRYPTO_MAX_ALG_NAME)
418 		goto out_free_salg;
419 
420 	alg->base.cra_flags = CRYPTO_ALG_ASYNC;
421 	alg->base.cra_priority = ialg->base.cra_priority;
422 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
423 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
424 	alg->base.cra_module = ialg->base.cra_module;
425 	alg->base.cra_ctxsize = sizeof(struct simd_aead_ctx);
426 
427 	alg->ivsize = ialg->ivsize;
428 	alg->maxauthsize = ialg->maxauthsize;
429 	alg->chunksize = ialg->chunksize;
430 
431 	alg->init = simd_aead_init;
432 	alg->exit = simd_aead_exit;
433 
434 	alg->setkey = simd_aead_setkey;
435 	alg->setauthsize = simd_aead_setauthsize;
436 	alg->encrypt = simd_aead_encrypt;
437 	alg->decrypt = simd_aead_decrypt;
438 
439 	err = crypto_register_aead(alg);
440 	if (err)
441 		goto out_free_salg;
442 
443 out_put_tfm:
444 	crypto_free_aead(tfm);
445 	return salg;
446 
447 out_free_salg:
448 	kfree(salg);
449 	salg = ERR_PTR(err);
450 	goto out_put_tfm;
451 }
452 EXPORT_SYMBOL_GPL(simd_aead_create_compat);
453 
454 struct simd_aead_alg *simd_aead_create(const char *algname,
455 				       const char *basename)
456 {
457 	char drvname[CRYPTO_MAX_ALG_NAME];
458 
459 	if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
460 	    CRYPTO_MAX_ALG_NAME)
461 		return ERR_PTR(-ENAMETOOLONG);
462 
463 	return simd_aead_create_compat(algname, drvname, basename);
464 }
465 EXPORT_SYMBOL_GPL(simd_aead_create);
466 
467 void simd_aead_free(struct simd_aead_alg *salg)
468 {
469 	crypto_unregister_aead(&salg->alg);
470 	kfree(salg);
471 }
472 EXPORT_SYMBOL_GPL(simd_aead_free);
473 
474 int simd_register_aeads_compat(struct aead_alg *algs, int count,
475 			       struct simd_aead_alg **simd_algs)
476 {
477 	int err;
478 	int i;
479 	const char *algname;
480 	const char *drvname;
481 	const char *basename;
482 	struct simd_aead_alg *simd;
483 
484 	err = crypto_register_aeads(algs, count);
485 	if (err)
486 		return err;
487 
488 	for (i = 0; i < count; i++) {
489 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
490 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
491 		algname = algs[i].base.cra_name + 2;
492 		drvname = algs[i].base.cra_driver_name + 2;
493 		basename = algs[i].base.cra_driver_name;
494 		simd = simd_aead_create_compat(algname, drvname, basename);
495 		err = PTR_ERR(simd);
496 		if (IS_ERR(simd))
497 			goto err_unregister;
498 		simd_algs[i] = simd;
499 	}
500 	return 0;
501 
502 err_unregister:
503 	simd_unregister_aeads(algs, count, simd_algs);
504 	return err;
505 }
506 EXPORT_SYMBOL_GPL(simd_register_aeads_compat);
507 
508 void simd_unregister_aeads(struct aead_alg *algs, int count,
509 			   struct simd_aead_alg **simd_algs)
510 {
511 	int i;
512 
513 	crypto_unregister_aeads(algs, count);
514 
515 	for (i = 0; i < count; i++) {
516 		if (simd_algs[i]) {
517 			simd_aead_free(simd_algs[i]);
518 			simd_algs[i] = NULL;
519 		}
520 	}
521 }
522 EXPORT_SYMBOL_GPL(simd_unregister_aeads);
523 
524 MODULE_LICENSE("GPL");
525