xref: /openbmc/linux/crypto/simd.c (revision fd4d5cd7) 
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(struct skcipher_alg *ialg,
140 						      const char *algname,
141 						      const char *drvname,
142 						      const char *basename)
143 {
144 	struct simd_skcipher_alg *salg;
145 	struct skcipher_alg *alg;
146 	int err;
147 
148 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
149 	if (!salg) {
150 		salg = ERR_PTR(-ENOMEM);
151 		goto out;
152 	}
153 
154 	salg->ialg_name = basename;
155 	alg = &salg->alg;
156 
157 	err = -ENAMETOOLONG;
158 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
159 	    CRYPTO_MAX_ALG_NAME)
160 		goto out_free_salg;
161 
162 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
163 		     drvname) >= CRYPTO_MAX_ALG_NAME)
164 		goto out_free_salg;
165 
166 	alg->base.cra_flags = CRYPTO_ALG_ASYNC |
167 		(ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
168 	alg->base.cra_priority = ialg->base.cra_priority;
169 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
170 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
171 	alg->base.cra_module = ialg->base.cra_module;
172 	alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
173 
174 	alg->ivsize = ialg->ivsize;
175 	alg->chunksize = ialg->chunksize;
176 	alg->min_keysize = ialg->min_keysize;
177 	alg->max_keysize = ialg->max_keysize;
178 
179 	alg->init = simd_skcipher_init;
180 	alg->exit = simd_skcipher_exit;
181 
182 	alg->setkey = simd_skcipher_setkey;
183 	alg->encrypt = simd_skcipher_encrypt;
184 	alg->decrypt = simd_skcipher_decrypt;
185 
186 	err = crypto_register_skcipher(alg);
187 	if (err)
188 		goto out_free_salg;
189 
190 out:
191 	return salg;
192 
193 out_free_salg:
194 	kfree(salg);
195 	salg = ERR_PTR(err);
196 	goto out;
197 }
198 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
199 
200 void simd_skcipher_free(struct simd_skcipher_alg *salg)
201 {
202 	crypto_unregister_skcipher(&salg->alg);
203 	kfree(salg);
204 }
205 EXPORT_SYMBOL_GPL(simd_skcipher_free);
206 
207 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
208 				   struct simd_skcipher_alg **simd_algs)
209 {
210 	int err;
211 	int i;
212 	const char *algname;
213 	const char *drvname;
214 	const char *basename;
215 	struct simd_skcipher_alg *simd;
216 
217 	err = crypto_register_skciphers(algs, count);
218 	if (err)
219 		return err;
220 
221 	for (i = 0; i < count; i++) {
222 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
223 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
224 		algname = algs[i].base.cra_name + 2;
225 		drvname = algs[i].base.cra_driver_name + 2;
226 		basename = algs[i].base.cra_driver_name;
227 		simd = simd_skcipher_create_compat(algs + i, algname, drvname, basename);
228 		err = PTR_ERR(simd);
229 		if (IS_ERR(simd))
230 			goto err_unregister;
231 		simd_algs[i] = simd;
232 	}
233 	return 0;
234 
235 err_unregister:
236 	simd_unregister_skciphers(algs, count, simd_algs);
237 	return err;
238 }
239 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
240 
241 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
242 			       struct simd_skcipher_alg **simd_algs)
243 {
244 	int i;
245 
246 	crypto_unregister_skciphers(algs, count);
247 
248 	for (i = 0; i < count; i++) {
249 		if (simd_algs[i]) {
250 			simd_skcipher_free(simd_algs[i]);
251 			simd_algs[i] = NULL;
252 		}
253 	}
254 }
255 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
256 
257 /* AEAD support */
258 
259 struct simd_aead_alg {
260 	const char *ialg_name;
261 	struct aead_alg alg;
262 };
263 
264 struct simd_aead_ctx {
265 	struct cryptd_aead *cryptd_tfm;
266 };
267 
268 static int simd_aead_setkey(struct crypto_aead *tfm, const u8 *key,
269 				unsigned int key_len)
270 {
271 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
272 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
273 
274 	crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
275 	crypto_aead_set_flags(child, crypto_aead_get_flags(tfm) &
276 				     CRYPTO_TFM_REQ_MASK);
277 	return crypto_aead_setkey(child, key, key_len);
278 }
279 
280 static int simd_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
281 {
282 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
283 	struct crypto_aead *child = &ctx->cryptd_tfm->base;
284 
285 	return crypto_aead_setauthsize(child, authsize);
286 }
287 
288 static int simd_aead_encrypt(struct aead_request *req)
289 {
290 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
291 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
292 	struct aead_request *subreq;
293 	struct crypto_aead *child;
294 
295 	subreq = aead_request_ctx(req);
296 	*subreq = *req;
297 
298 	if (!crypto_simd_usable() ||
299 	    (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
300 		child = &ctx->cryptd_tfm->base;
301 	else
302 		child = cryptd_aead_child(ctx->cryptd_tfm);
303 
304 	aead_request_set_tfm(subreq, child);
305 
306 	return crypto_aead_encrypt(subreq);
307 }
308 
309 static int simd_aead_decrypt(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_decrypt(subreq);
328 }
329 
330 static void simd_aead_exit(struct crypto_aead *tfm)
331 {
332 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
333 
334 	cryptd_free_aead(ctx->cryptd_tfm);
335 }
336 
337 static int simd_aead_init(struct crypto_aead *tfm)
338 {
339 	struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
340 	struct cryptd_aead *cryptd_tfm;
341 	struct simd_aead_alg *salg;
342 	struct aead_alg *alg;
343 	unsigned reqsize;
344 
345 	alg = crypto_aead_alg(tfm);
346 	salg = container_of(alg, struct simd_aead_alg, alg);
347 
348 	cryptd_tfm = cryptd_alloc_aead(salg->ialg_name, CRYPTO_ALG_INTERNAL,
349 				       CRYPTO_ALG_INTERNAL);
350 	if (IS_ERR(cryptd_tfm))
351 		return PTR_ERR(cryptd_tfm);
352 
353 	ctx->cryptd_tfm = cryptd_tfm;
354 
355 	reqsize = crypto_aead_reqsize(cryptd_aead_child(cryptd_tfm));
356 	reqsize = max(reqsize, crypto_aead_reqsize(&cryptd_tfm->base));
357 	reqsize += sizeof(struct aead_request);
358 
359 	crypto_aead_set_reqsize(tfm, reqsize);
360 
361 	return 0;
362 }
363 
364 static struct simd_aead_alg *simd_aead_create_compat(struct aead_alg *ialg,
365 						     const char *algname,
366 						     const char *drvname,
367 						     const char *basename)
368 {
369 	struct simd_aead_alg *salg;
370 	struct aead_alg *alg;
371 	int err;
372 
373 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
374 	if (!salg) {
375 		salg = ERR_PTR(-ENOMEM);
376 		goto out;
377 	}
378 
379 	salg->ialg_name = basename;
380 	alg = &salg->alg;
381 
382 	err = -ENAMETOOLONG;
383 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
384 	    CRYPTO_MAX_ALG_NAME)
385 		goto out_free_salg;
386 
387 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
388 		     drvname) >= CRYPTO_MAX_ALG_NAME)
389 		goto out_free_salg;
390 
391 	alg->base.cra_flags = CRYPTO_ALG_ASYNC |
392 		(ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
393 	alg->base.cra_priority = ialg->base.cra_priority;
394 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
395 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
396 	alg->base.cra_module = ialg->base.cra_module;
397 	alg->base.cra_ctxsize = sizeof(struct simd_aead_ctx);
398 
399 	alg->ivsize = ialg->ivsize;
400 	alg->maxauthsize = ialg->maxauthsize;
401 	alg->chunksize = ialg->chunksize;
402 
403 	alg->init = simd_aead_init;
404 	alg->exit = simd_aead_exit;
405 
406 	alg->setkey = simd_aead_setkey;
407 	alg->setauthsize = simd_aead_setauthsize;
408 	alg->encrypt = simd_aead_encrypt;
409 	alg->decrypt = simd_aead_decrypt;
410 
411 	err = crypto_register_aead(alg);
412 	if (err)
413 		goto out_free_salg;
414 
415 out:
416 	return salg;
417 
418 out_free_salg:
419 	kfree(salg);
420 	salg = ERR_PTR(err);
421 	goto out;
422 }
423 
424 static void simd_aead_free(struct simd_aead_alg *salg)
425 {
426 	crypto_unregister_aead(&salg->alg);
427 	kfree(salg);
428 }
429 
430 int simd_register_aeads_compat(struct aead_alg *algs, int count,
431 			       struct simd_aead_alg **simd_algs)
432 {
433 	int err;
434 	int i;
435 	const char *algname;
436 	const char *drvname;
437 	const char *basename;
438 	struct simd_aead_alg *simd;
439 
440 	err = crypto_register_aeads(algs, count);
441 	if (err)
442 		return err;
443 
444 	for (i = 0; i < count; i++) {
445 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
446 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
447 		algname = algs[i].base.cra_name + 2;
448 		drvname = algs[i].base.cra_driver_name + 2;
449 		basename = algs[i].base.cra_driver_name;
450 		simd = simd_aead_create_compat(algs + i, algname, drvname, basename);
451 		err = PTR_ERR(simd);
452 		if (IS_ERR(simd))
453 			goto err_unregister;
454 		simd_algs[i] = simd;
455 	}
456 	return 0;
457 
458 err_unregister:
459 	simd_unregister_aeads(algs, count, simd_algs);
460 	return err;
461 }
462 EXPORT_SYMBOL_GPL(simd_register_aeads_compat);
463 
464 void simd_unregister_aeads(struct aead_alg *algs, int count,
465 			   struct simd_aead_alg **simd_algs)
466 {
467 	int i;
468 
469 	crypto_unregister_aeads(algs, count);
470 
471 	for (i = 0; i < count; i++) {
472 		if (simd_algs[i]) {
473 			simd_aead_free(simd_algs[i]);
474 			simd_algs[i] = NULL;
475 		}
476 	}
477 }
478 EXPORT_SYMBOL_GPL(simd_unregister_aeads);
479 
480 MODULE_LICENSE("GPL");
481