xref: /openbmc/linux/crypto/shash.c (revision cd4d09ec)
1 /*
2  * Synchronous Cryptographic Hash operations.
3  *
4  * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <crypto/scatterwalk.h>
14 #include <crypto/internal/hash.h>
15 #include <linux/err.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/seq_file.h>
20 #include <linux/cryptouser.h>
21 #include <net/netlink.h>
22 
23 #include "internal.h"
24 
25 static const struct crypto_type crypto_shash_type;
26 
27 static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
28 			   unsigned int keylen)
29 {
30 	return -ENOSYS;
31 }
32 
33 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
34 				  unsigned int keylen)
35 {
36 	struct shash_alg *shash = crypto_shash_alg(tfm);
37 	unsigned long alignmask = crypto_shash_alignmask(tfm);
38 	unsigned long absize;
39 	u8 *buffer, *alignbuffer;
40 	int err;
41 
42 	absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
43 	buffer = kmalloc(absize, GFP_KERNEL);
44 	if (!buffer)
45 		return -ENOMEM;
46 
47 	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
48 	memcpy(alignbuffer, key, keylen);
49 	err = shash->setkey(tfm, alignbuffer, keylen);
50 	kzfree(buffer);
51 	return err;
52 }
53 
54 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
55 			unsigned int keylen)
56 {
57 	struct shash_alg *shash = crypto_shash_alg(tfm);
58 	unsigned long alignmask = crypto_shash_alignmask(tfm);
59 
60 	if ((unsigned long)key & alignmask)
61 		return shash_setkey_unaligned(tfm, key, keylen);
62 
63 	return shash->setkey(tfm, key, keylen);
64 }
65 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
66 
67 static inline unsigned int shash_align_buffer_size(unsigned len,
68 						   unsigned long mask)
69 {
70 	typedef u8 __attribute__ ((aligned)) u8_aligned;
71 	return len + (mask & ~(__alignof__(u8_aligned) - 1));
72 }
73 
74 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
75 				  unsigned int len)
76 {
77 	struct crypto_shash *tfm = desc->tfm;
78 	struct shash_alg *shash = crypto_shash_alg(tfm);
79 	unsigned long alignmask = crypto_shash_alignmask(tfm);
80 	unsigned int unaligned_len = alignmask + 1 -
81 				     ((unsigned long)data & alignmask);
82 	u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)]
83 		__attribute__ ((aligned));
84 	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
85 	int err;
86 
87 	if (unaligned_len > len)
88 		unaligned_len = len;
89 
90 	memcpy(buf, data, unaligned_len);
91 	err = shash->update(desc, buf, unaligned_len);
92 	memset(buf, 0, unaligned_len);
93 
94 	return err ?:
95 	       shash->update(desc, data + unaligned_len, len - unaligned_len);
96 }
97 
98 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
99 			unsigned int len)
100 {
101 	struct crypto_shash *tfm = desc->tfm;
102 	struct shash_alg *shash = crypto_shash_alg(tfm);
103 	unsigned long alignmask = crypto_shash_alignmask(tfm);
104 
105 	if ((unsigned long)data & alignmask)
106 		return shash_update_unaligned(desc, data, len);
107 
108 	return shash->update(desc, data, len);
109 }
110 EXPORT_SYMBOL_GPL(crypto_shash_update);
111 
112 static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
113 {
114 	struct crypto_shash *tfm = desc->tfm;
115 	unsigned long alignmask = crypto_shash_alignmask(tfm);
116 	struct shash_alg *shash = crypto_shash_alg(tfm);
117 	unsigned int ds = crypto_shash_digestsize(tfm);
118 	u8 ubuf[shash_align_buffer_size(ds, alignmask)]
119 		__attribute__ ((aligned));
120 	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
121 	int err;
122 
123 	err = shash->final(desc, buf);
124 	if (err)
125 		goto out;
126 
127 	memcpy(out, buf, ds);
128 
129 out:
130 	memset(buf, 0, ds);
131 	return err;
132 }
133 
134 int crypto_shash_final(struct shash_desc *desc, u8 *out)
135 {
136 	struct crypto_shash *tfm = desc->tfm;
137 	struct shash_alg *shash = crypto_shash_alg(tfm);
138 	unsigned long alignmask = crypto_shash_alignmask(tfm);
139 
140 	if ((unsigned long)out & alignmask)
141 		return shash_final_unaligned(desc, out);
142 
143 	return shash->final(desc, out);
144 }
145 EXPORT_SYMBOL_GPL(crypto_shash_final);
146 
147 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
148 				 unsigned int len, u8 *out)
149 {
150 	return crypto_shash_update(desc, data, len) ?:
151 	       crypto_shash_final(desc, out);
152 }
153 
154 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
155 		       unsigned int len, u8 *out)
156 {
157 	struct crypto_shash *tfm = desc->tfm;
158 	struct shash_alg *shash = crypto_shash_alg(tfm);
159 	unsigned long alignmask = crypto_shash_alignmask(tfm);
160 
161 	if (((unsigned long)data | (unsigned long)out) & alignmask)
162 		return shash_finup_unaligned(desc, data, len, out);
163 
164 	return shash->finup(desc, data, len, out);
165 }
166 EXPORT_SYMBOL_GPL(crypto_shash_finup);
167 
168 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
169 				  unsigned int len, u8 *out)
170 {
171 	return crypto_shash_init(desc) ?:
172 	       crypto_shash_finup(desc, data, len, out);
173 }
174 
175 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
176 			unsigned int len, u8 *out)
177 {
178 	struct crypto_shash *tfm = desc->tfm;
179 	struct shash_alg *shash = crypto_shash_alg(tfm);
180 	unsigned long alignmask = crypto_shash_alignmask(tfm);
181 
182 	if (((unsigned long)data | (unsigned long)out) & alignmask)
183 		return shash_digest_unaligned(desc, data, len, out);
184 
185 	return shash->digest(desc, data, len, out);
186 }
187 EXPORT_SYMBOL_GPL(crypto_shash_digest);
188 
189 static int shash_default_export(struct shash_desc *desc, void *out)
190 {
191 	memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
192 	return 0;
193 }
194 
195 static int shash_default_import(struct shash_desc *desc, const void *in)
196 {
197 	memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
198 	return 0;
199 }
200 
201 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
202 			      unsigned int keylen)
203 {
204 	struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
205 
206 	return crypto_shash_setkey(*ctx, key, keylen);
207 }
208 
209 static int shash_async_init(struct ahash_request *req)
210 {
211 	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
212 	struct shash_desc *desc = ahash_request_ctx(req);
213 
214 	desc->tfm = *ctx;
215 	desc->flags = req->base.flags;
216 
217 	return crypto_shash_init(desc);
218 }
219 
220 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
221 {
222 	struct crypto_hash_walk walk;
223 	int nbytes;
224 
225 	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
226 	     nbytes = crypto_hash_walk_done(&walk, nbytes))
227 		nbytes = crypto_shash_update(desc, walk.data, nbytes);
228 
229 	return nbytes;
230 }
231 EXPORT_SYMBOL_GPL(shash_ahash_update);
232 
233 static int shash_async_update(struct ahash_request *req)
234 {
235 	return shash_ahash_update(req, ahash_request_ctx(req));
236 }
237 
238 static int shash_async_final(struct ahash_request *req)
239 {
240 	return crypto_shash_final(ahash_request_ctx(req), req->result);
241 }
242 
243 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
244 {
245 	struct crypto_hash_walk walk;
246 	int nbytes;
247 
248 	nbytes = crypto_hash_walk_first(req, &walk);
249 	if (!nbytes)
250 		return crypto_shash_final(desc, req->result);
251 
252 	do {
253 		nbytes = crypto_hash_walk_last(&walk) ?
254 			 crypto_shash_finup(desc, walk.data, nbytes,
255 					    req->result) :
256 			 crypto_shash_update(desc, walk.data, nbytes);
257 		nbytes = crypto_hash_walk_done(&walk, nbytes);
258 	} while (nbytes > 0);
259 
260 	return nbytes;
261 }
262 EXPORT_SYMBOL_GPL(shash_ahash_finup);
263 
264 static int shash_async_finup(struct ahash_request *req)
265 {
266 	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
267 	struct shash_desc *desc = ahash_request_ctx(req);
268 
269 	desc->tfm = *ctx;
270 	desc->flags = req->base.flags;
271 
272 	return shash_ahash_finup(req, desc);
273 }
274 
275 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
276 {
277 	struct scatterlist *sg = req->src;
278 	unsigned int offset = sg->offset;
279 	unsigned int nbytes = req->nbytes;
280 	int err;
281 
282 	if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
283 		void *data;
284 
285 		data = kmap_atomic(sg_page(sg));
286 		err = crypto_shash_digest(desc, data + offset, nbytes,
287 					  req->result);
288 		kunmap_atomic(data);
289 		crypto_yield(desc->flags);
290 	} else
291 		err = crypto_shash_init(desc) ?:
292 		      shash_ahash_finup(req, desc);
293 
294 	return err;
295 }
296 EXPORT_SYMBOL_GPL(shash_ahash_digest);
297 
298 static int shash_async_digest(struct ahash_request *req)
299 {
300 	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
301 	struct shash_desc *desc = ahash_request_ctx(req);
302 
303 	desc->tfm = *ctx;
304 	desc->flags = req->base.flags;
305 
306 	return shash_ahash_digest(req, desc);
307 }
308 
309 static int shash_async_export(struct ahash_request *req, void *out)
310 {
311 	return crypto_shash_export(ahash_request_ctx(req), out);
312 }
313 
314 static int shash_async_import(struct ahash_request *req, const void *in)
315 {
316 	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
317 	struct shash_desc *desc = ahash_request_ctx(req);
318 
319 	desc->tfm = *ctx;
320 	desc->flags = req->base.flags;
321 
322 	return crypto_shash_import(desc, in);
323 }
324 
325 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
326 {
327 	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
328 
329 	crypto_free_shash(*ctx);
330 }
331 
332 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
333 {
334 	struct crypto_alg *calg = tfm->__crt_alg;
335 	struct shash_alg *alg = __crypto_shash_alg(calg);
336 	struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
337 	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
338 	struct crypto_shash *shash;
339 
340 	if (!crypto_mod_get(calg))
341 		return -EAGAIN;
342 
343 	shash = crypto_create_tfm(calg, &crypto_shash_type);
344 	if (IS_ERR(shash)) {
345 		crypto_mod_put(calg);
346 		return PTR_ERR(shash);
347 	}
348 
349 	*ctx = shash;
350 	tfm->exit = crypto_exit_shash_ops_async;
351 
352 	crt->init = shash_async_init;
353 	crt->update = shash_async_update;
354 	crt->final = shash_async_final;
355 	crt->finup = shash_async_finup;
356 	crt->digest = shash_async_digest;
357 
358 	if (alg->setkey) {
359 		crt->setkey = shash_async_setkey;
360 		crt->has_setkey = true;
361 	}
362 	if (alg->export)
363 		crt->export = shash_async_export;
364 	if (alg->import)
365 		crt->import = shash_async_import;
366 
367 	crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
368 
369 	return 0;
370 }
371 
372 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
373 			       unsigned int keylen)
374 {
375 	struct shash_desc **descp = crypto_hash_ctx(tfm);
376 	struct shash_desc *desc = *descp;
377 
378 	return crypto_shash_setkey(desc->tfm, key, keylen);
379 }
380 
381 static int shash_compat_init(struct hash_desc *hdesc)
382 {
383 	struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
384 	struct shash_desc *desc = *descp;
385 
386 	desc->flags = hdesc->flags;
387 
388 	return crypto_shash_init(desc);
389 }
390 
391 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
392 			       unsigned int len)
393 {
394 	struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
395 	struct shash_desc *desc = *descp;
396 	struct crypto_hash_walk walk;
397 	int nbytes;
398 
399 	for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len);
400 	     nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes))
401 		nbytes = crypto_shash_update(desc, walk.data, nbytes);
402 
403 	return nbytes;
404 }
405 
406 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
407 {
408 	struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
409 
410 	return crypto_shash_final(*descp, out);
411 }
412 
413 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
414 			       unsigned int nbytes, u8 *out)
415 {
416 	unsigned int offset = sg->offset;
417 	int err;
418 
419 	if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
420 		struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
421 		struct shash_desc *desc = *descp;
422 		void *data;
423 
424 		desc->flags = hdesc->flags;
425 
426 		data = kmap_atomic(sg_page(sg));
427 		err = crypto_shash_digest(desc, data + offset, nbytes, out);
428 		kunmap_atomic(data);
429 		crypto_yield(desc->flags);
430 		goto out;
431 	}
432 
433 	err = shash_compat_init(hdesc);
434 	if (err)
435 		goto out;
436 
437 	err = shash_compat_update(hdesc, sg, nbytes);
438 	if (err)
439 		goto out;
440 
441 	err = shash_compat_final(hdesc, out);
442 
443 out:
444 	return err;
445 }
446 
447 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
448 {
449 	struct shash_desc **descp = crypto_tfm_ctx(tfm);
450 	struct shash_desc *desc = *descp;
451 
452 	crypto_free_shash(desc->tfm);
453 	kzfree(desc);
454 }
455 
456 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
457 {
458 	struct hash_tfm *crt = &tfm->crt_hash;
459 	struct crypto_alg *calg = tfm->__crt_alg;
460 	struct shash_alg *alg = __crypto_shash_alg(calg);
461 	struct shash_desc **descp = crypto_tfm_ctx(tfm);
462 	struct crypto_shash *shash;
463 	struct shash_desc *desc;
464 
465 	if (!crypto_mod_get(calg))
466 		return -EAGAIN;
467 
468 	shash = crypto_create_tfm(calg, &crypto_shash_type);
469 	if (IS_ERR(shash)) {
470 		crypto_mod_put(calg);
471 		return PTR_ERR(shash);
472 	}
473 
474 	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
475 		       GFP_KERNEL);
476 	if (!desc) {
477 		crypto_free_shash(shash);
478 		return -ENOMEM;
479 	}
480 
481 	*descp = desc;
482 	desc->tfm = shash;
483 	tfm->exit = crypto_exit_shash_ops_compat;
484 
485 	crt->init = shash_compat_init;
486 	crt->update = shash_compat_update;
487 	crt->final  = shash_compat_final;
488 	crt->digest = shash_compat_digest;
489 	crt->setkey = shash_compat_setkey;
490 
491 	crt->digestsize = alg->digestsize;
492 
493 	return 0;
494 }
495 
496 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
497 {
498 	switch (mask & CRYPTO_ALG_TYPE_MASK) {
499 	case CRYPTO_ALG_TYPE_HASH_MASK:
500 		return crypto_init_shash_ops_compat(tfm);
501 	}
502 
503 	return -EINVAL;
504 }
505 
506 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
507 					 u32 mask)
508 {
509 	switch (mask & CRYPTO_ALG_TYPE_MASK) {
510 	case CRYPTO_ALG_TYPE_HASH_MASK:
511 		return sizeof(struct shash_desc *);
512 	}
513 
514 	return 0;
515 }
516 
517 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
518 {
519 	struct crypto_shash *hash = __crypto_shash_cast(tfm);
520 
521 	hash->descsize = crypto_shash_alg(hash)->descsize;
522 	return 0;
523 }
524 
525 #ifdef CONFIG_NET
526 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
527 {
528 	struct crypto_report_hash rhash;
529 	struct shash_alg *salg = __crypto_shash_alg(alg);
530 
531 	strncpy(rhash.type, "shash", sizeof(rhash.type));
532 
533 	rhash.blocksize = alg->cra_blocksize;
534 	rhash.digestsize = salg->digestsize;
535 
536 	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
537 		    sizeof(struct crypto_report_hash), &rhash))
538 		goto nla_put_failure;
539 	return 0;
540 
541 nla_put_failure:
542 	return -EMSGSIZE;
543 }
544 #else
545 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
546 {
547 	return -ENOSYS;
548 }
549 #endif
550 
551 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
552 	__attribute__ ((unused));
553 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
554 {
555 	struct shash_alg *salg = __crypto_shash_alg(alg);
556 
557 	seq_printf(m, "type         : shash\n");
558 	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
559 	seq_printf(m, "digestsize   : %u\n", salg->digestsize);
560 }
561 
562 static const struct crypto_type crypto_shash_type = {
563 	.ctxsize = crypto_shash_ctxsize,
564 	.extsize = crypto_alg_extsize,
565 	.init = crypto_init_shash_ops,
566 	.init_tfm = crypto_shash_init_tfm,
567 #ifdef CONFIG_PROC_FS
568 	.show = crypto_shash_show,
569 #endif
570 	.report = crypto_shash_report,
571 	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
572 	.maskset = CRYPTO_ALG_TYPE_MASK,
573 	.type = CRYPTO_ALG_TYPE_SHASH,
574 	.tfmsize = offsetof(struct crypto_shash, base),
575 };
576 
577 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
578 					u32 mask)
579 {
580 	return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
581 }
582 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
583 
584 static int shash_prepare_alg(struct shash_alg *alg)
585 {
586 	struct crypto_alg *base = &alg->base;
587 
588 	if (alg->digestsize > PAGE_SIZE / 8 ||
589 	    alg->descsize > PAGE_SIZE / 8 ||
590 	    alg->statesize > PAGE_SIZE / 8)
591 		return -EINVAL;
592 
593 	base->cra_type = &crypto_shash_type;
594 	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
595 	base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
596 
597 	if (!alg->finup)
598 		alg->finup = shash_finup_unaligned;
599 	if (!alg->digest)
600 		alg->digest = shash_digest_unaligned;
601 	if (!alg->export) {
602 		alg->export = shash_default_export;
603 		alg->import = shash_default_import;
604 		alg->statesize = alg->descsize;
605 	}
606 	if (!alg->setkey)
607 		alg->setkey = shash_no_setkey;
608 
609 	return 0;
610 }
611 
612 int crypto_register_shash(struct shash_alg *alg)
613 {
614 	struct crypto_alg *base = &alg->base;
615 	int err;
616 
617 	err = shash_prepare_alg(alg);
618 	if (err)
619 		return err;
620 
621 	return crypto_register_alg(base);
622 }
623 EXPORT_SYMBOL_GPL(crypto_register_shash);
624 
625 int crypto_unregister_shash(struct shash_alg *alg)
626 {
627 	return crypto_unregister_alg(&alg->base);
628 }
629 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
630 
631 int crypto_register_shashes(struct shash_alg *algs, int count)
632 {
633 	int i, ret;
634 
635 	for (i = 0; i < count; i++) {
636 		ret = crypto_register_shash(&algs[i]);
637 		if (ret)
638 			goto err;
639 	}
640 
641 	return 0;
642 
643 err:
644 	for (--i; i >= 0; --i)
645 		crypto_unregister_shash(&algs[i]);
646 
647 	return ret;
648 }
649 EXPORT_SYMBOL_GPL(crypto_register_shashes);
650 
651 int crypto_unregister_shashes(struct shash_alg *algs, int count)
652 {
653 	int i, ret;
654 
655 	for (i = count - 1; i >= 0; --i) {
656 		ret = crypto_unregister_shash(&algs[i]);
657 		if (ret)
658 			pr_err("Failed to unregister %s %s: %d\n",
659 			       algs[i].base.cra_driver_name,
660 			       algs[i].base.cra_name, ret);
661 	}
662 
663 	return 0;
664 }
665 EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
666 
667 int shash_register_instance(struct crypto_template *tmpl,
668 			    struct shash_instance *inst)
669 {
670 	int err;
671 
672 	err = shash_prepare_alg(&inst->alg);
673 	if (err)
674 		return err;
675 
676 	return crypto_register_instance(tmpl, shash_crypto_instance(inst));
677 }
678 EXPORT_SYMBOL_GPL(shash_register_instance);
679 
680 void shash_free_instance(struct crypto_instance *inst)
681 {
682 	crypto_drop_spawn(crypto_instance_ctx(inst));
683 	kfree(shash_instance(inst));
684 }
685 EXPORT_SYMBOL_GPL(shash_free_instance);
686 
687 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
688 			    struct shash_alg *alg,
689 			    struct crypto_instance *inst)
690 {
691 	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
692 				  &crypto_shash_type);
693 }
694 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
695 
696 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
697 {
698 	struct crypto_alg *alg;
699 
700 	alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
701 	return IS_ERR(alg) ? ERR_CAST(alg) :
702 	       container_of(alg, struct shash_alg, base);
703 }
704 EXPORT_SYMBOL_GPL(shash_attr_alg);
705 
706 MODULE_LICENSE("GPL");
707 MODULE_DESCRIPTION("Synchronous cryptographic hash type");
708