1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Asymmetric public-key cryptography key type
3  *
4  * See Documentation/crypto/asymmetric-keys.rst
5  *
6  * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
7  * Written by David Howells (dhowells@redhat.com)
8  */
9 #include <keys/asymmetric-subtype.h>
10 #include <keys/asymmetric-parser.h>
11 #include <crypto/public_key.h>
12 #include <linux/seq_file.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/ctype.h>
16 #include <keys/system_keyring.h>
17 #include <keys/user-type.h>
18 #include "asymmetric_keys.h"
19 
20 MODULE_LICENSE("GPL");
21 
22 const char *const key_being_used_for[NR__KEY_BEING_USED_FOR] = {
23 	[VERIFYING_MODULE_SIGNATURE]		= "mod sig",
24 	[VERIFYING_FIRMWARE_SIGNATURE]		= "firmware sig",
25 	[VERIFYING_KEXEC_PE_SIGNATURE]		= "kexec PE sig",
26 	[VERIFYING_KEY_SIGNATURE]		= "key sig",
27 	[VERIFYING_KEY_SELF_SIGNATURE]		= "key self sig",
28 	[VERIFYING_UNSPECIFIED_SIGNATURE]	= "unspec sig",
29 };
30 EXPORT_SYMBOL_GPL(key_being_used_for);
31 
32 static LIST_HEAD(asymmetric_key_parsers);
33 static DECLARE_RWSEM(asymmetric_key_parsers_sem);
34 
35 /**
36  * find_asymmetric_key - Find a key by ID.
37  * @keyring: The keys to search.
38  * @id_0: The first ID to look for or NULL.
39  * @id_1: The second ID to look for or NULL, matched together with @id_0
40  * against @keyring keys' id[0] and id[1].
41  * @id_2: The fallback ID to match against @keyring keys' id[2] if both of the
42  * other IDs are NULL.
43  * @partial: Use partial match for @id_0 and @id_1 if true, exact if false.
44  *
45  * Find a key in the given keyring by identifier.  The preferred identifier is
46  * the id_0 and the fallback identifier is the id_1.  If both are given, the
47  * former is matched (exactly or partially) against either of the sought key's
48  * identifiers and the latter must match the found key's second identifier
49  * exactly.  If both are missing, id_2 must match the sought key's third
50  * identifier exactly.
51  */
find_asymmetric_key(struct key * keyring,const struct asymmetric_key_id * id_0,const struct asymmetric_key_id * id_1,const struct asymmetric_key_id * id_2,bool partial)52 struct key *find_asymmetric_key(struct key *keyring,
53 				const struct asymmetric_key_id *id_0,
54 				const struct asymmetric_key_id *id_1,
55 				const struct asymmetric_key_id *id_2,
56 				bool partial)
57 {
58 	struct key *key;
59 	key_ref_t ref;
60 	const char *lookup;
61 	char *req, *p;
62 	int len;
63 
64 	WARN_ON(!id_0 && !id_1 && !id_2);
65 
66 	if (id_0) {
67 		lookup = id_0->data;
68 		len = id_0->len;
69 	} else if (id_1) {
70 		lookup = id_1->data;
71 		len = id_1->len;
72 	} else {
73 		lookup = id_2->data;
74 		len = id_2->len;
75 	}
76 
77 	/* Construct an identifier "id:<keyid>". */
78 	p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL);
79 	if (!req)
80 		return ERR_PTR(-ENOMEM);
81 
82 	if (!id_0 && !id_1) {
83 		*p++ = 'd';
84 		*p++ = 'n';
85 	} else if (partial) {
86 		*p++ = 'i';
87 		*p++ = 'd';
88 	} else {
89 		*p++ = 'e';
90 		*p++ = 'x';
91 	}
92 	*p++ = ':';
93 	p = bin2hex(p, lookup, len);
94 	*p = 0;
95 
96 	pr_debug("Look up: \"%s\"\n", req);
97 
98 	ref = keyring_search(make_key_ref(keyring, 1),
99 			     &key_type_asymmetric, req, true);
100 	if (IS_ERR(ref))
101 		pr_debug("Request for key '%s' err %ld\n", req, PTR_ERR(ref));
102 	kfree(req);
103 
104 	if (IS_ERR(ref)) {
105 		switch (PTR_ERR(ref)) {
106 			/* Hide some search errors */
107 		case -EACCES:
108 		case -ENOTDIR:
109 		case -EAGAIN:
110 			return ERR_PTR(-ENOKEY);
111 		default:
112 			return ERR_CAST(ref);
113 		}
114 	}
115 
116 	key = key_ref_to_ptr(ref);
117 	if (id_0 && id_1) {
118 		const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
119 
120 		if (!kids->id[1]) {
121 			pr_debug("First ID matches, but second is missing\n");
122 			goto reject;
123 		}
124 		if (!asymmetric_key_id_same(id_1, kids->id[1])) {
125 			pr_debug("First ID matches, but second does not\n");
126 			goto reject;
127 		}
128 	}
129 
130 	pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key));
131 	return key;
132 
133 reject:
134 	key_put(key);
135 	return ERR_PTR(-EKEYREJECTED);
136 }
137 EXPORT_SYMBOL_GPL(find_asymmetric_key);
138 
139 /**
140  * asymmetric_key_generate_id: Construct an asymmetric key ID
141  * @val_1: First binary blob
142  * @len_1: Length of first binary blob
143  * @val_2: Second binary blob
144  * @len_2: Length of second binary blob
145  *
146  * Construct an asymmetric key ID from a pair of binary blobs.
147  */
asymmetric_key_generate_id(const void * val_1,size_t len_1,const void * val_2,size_t len_2)148 struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1,
149 						     size_t len_1,
150 						     const void *val_2,
151 						     size_t len_2)
152 {
153 	struct asymmetric_key_id *kid;
154 
155 	kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2,
156 		      GFP_KERNEL);
157 	if (!kid)
158 		return ERR_PTR(-ENOMEM);
159 	kid->len = len_1 + len_2;
160 	memcpy(kid->data, val_1, len_1);
161 	memcpy(kid->data + len_1, val_2, len_2);
162 	return kid;
163 }
164 EXPORT_SYMBOL_GPL(asymmetric_key_generate_id);
165 
166 /**
167  * asymmetric_key_id_same - Return true if two asymmetric keys IDs are the same.
168  * @kid1: The key ID to compare
169  * @kid2: The key ID to compare
170  */
asymmetric_key_id_same(const struct asymmetric_key_id * kid1,const struct asymmetric_key_id * kid2)171 bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
172 			    const struct asymmetric_key_id *kid2)
173 {
174 	if (!kid1 || !kid2)
175 		return false;
176 	if (kid1->len != kid2->len)
177 		return false;
178 	return memcmp(kid1->data, kid2->data, kid1->len) == 0;
179 }
180 EXPORT_SYMBOL_GPL(asymmetric_key_id_same);
181 
182 /**
183  * asymmetric_key_id_partial - Return true if two asymmetric keys IDs
184  * partially match
185  * @kid1: The key ID to compare
186  * @kid2: The key ID to compare
187  */
asymmetric_key_id_partial(const struct asymmetric_key_id * kid1,const struct asymmetric_key_id * kid2)188 bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
189 			       const struct asymmetric_key_id *kid2)
190 {
191 	if (!kid1 || !kid2)
192 		return false;
193 	if (kid1->len < kid2->len)
194 		return false;
195 	return memcmp(kid1->data + (kid1->len - kid2->len),
196 		      kid2->data, kid2->len) == 0;
197 }
198 EXPORT_SYMBOL_GPL(asymmetric_key_id_partial);
199 
200 /**
201  * asymmetric_match_key_ids - Search asymmetric key IDs 1 & 2
202  * @kids: The pair of key IDs to check
203  * @match_id: The key ID we're looking for
204  * @match: The match function to use
205  */
asymmetric_match_key_ids(const struct asymmetric_key_ids * kids,const struct asymmetric_key_id * match_id,bool (* match)(const struct asymmetric_key_id * kid1,const struct asymmetric_key_id * kid2))206 static bool asymmetric_match_key_ids(
207 	const struct asymmetric_key_ids *kids,
208 	const struct asymmetric_key_id *match_id,
209 	bool (*match)(const struct asymmetric_key_id *kid1,
210 		      const struct asymmetric_key_id *kid2))
211 {
212 	int i;
213 
214 	if (!kids || !match_id)
215 		return false;
216 	for (i = 0; i < 2; i++)
217 		if (match(kids->id[i], match_id))
218 			return true;
219 	return false;
220 }
221 
222 /* helper function can be called directly with pre-allocated memory */
__asymmetric_key_hex_to_key_id(const char * id,struct asymmetric_key_id * match_id,size_t hexlen)223 inline int __asymmetric_key_hex_to_key_id(const char *id,
224 				   struct asymmetric_key_id *match_id,
225 				   size_t hexlen)
226 {
227 	match_id->len = hexlen;
228 	return hex2bin(match_id->data, id, hexlen);
229 }
230 
231 /**
232  * asymmetric_key_hex_to_key_id - Convert a hex string into a key ID.
233  * @id: The ID as a hex string.
234  */
asymmetric_key_hex_to_key_id(const char * id)235 struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
236 {
237 	struct asymmetric_key_id *match_id;
238 	size_t asciihexlen;
239 	int ret;
240 
241 	if (!*id)
242 		return ERR_PTR(-EINVAL);
243 	asciihexlen = strlen(id);
244 	if (asciihexlen & 1)
245 		return ERR_PTR(-EINVAL);
246 
247 	match_id = kmalloc(sizeof(struct asymmetric_key_id) + asciihexlen / 2,
248 			   GFP_KERNEL);
249 	if (!match_id)
250 		return ERR_PTR(-ENOMEM);
251 	ret = __asymmetric_key_hex_to_key_id(id, match_id, asciihexlen / 2);
252 	if (ret < 0) {
253 		kfree(match_id);
254 		return ERR_PTR(-EINVAL);
255 	}
256 	return match_id;
257 }
258 
259 /*
260  * Match asymmetric keys by an exact match on one of the first two IDs.
261  */
asymmetric_key_cmp(const struct key * key,const struct key_match_data * match_data)262 static bool asymmetric_key_cmp(const struct key *key,
263 			       const struct key_match_data *match_data)
264 {
265 	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
266 	const struct asymmetric_key_id *match_id = match_data->preparsed;
267 
268 	return asymmetric_match_key_ids(kids, match_id,
269 					asymmetric_key_id_same);
270 }
271 
272 /*
273  * Match asymmetric keys by a partial match on one of the first two IDs.
274  */
asymmetric_key_cmp_partial(const struct key * key,const struct key_match_data * match_data)275 static bool asymmetric_key_cmp_partial(const struct key *key,
276 				       const struct key_match_data *match_data)
277 {
278 	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
279 	const struct asymmetric_key_id *match_id = match_data->preparsed;
280 
281 	return asymmetric_match_key_ids(kids, match_id,
282 					asymmetric_key_id_partial);
283 }
284 
285 /*
286  * Match asymmetric keys by an exact match on the third IDs.
287  */
asymmetric_key_cmp_name(const struct key * key,const struct key_match_data * match_data)288 static bool asymmetric_key_cmp_name(const struct key *key,
289 				    const struct key_match_data *match_data)
290 {
291 	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
292 	const struct asymmetric_key_id *match_id = match_data->preparsed;
293 
294 	return kids && asymmetric_key_id_same(kids->id[2], match_id);
295 }
296 
297 /*
298  * Preparse the match criterion.  If we don't set lookup_type and cmp,
299  * the default will be an exact match on the key description.
300  *
301  * There are some specifiers for matching key IDs rather than by the key
302  * description:
303  *
304  *	"id:<id>" - find a key by partial match on one of the first two IDs
305  *	"ex:<id>" - find a key by exact match on one of the first two IDs
306  *	"dn:<id>" - find a key by exact match on the third ID
307  *
308  * These have to be searched by iteration rather than by direct lookup because
309  * the key is hashed according to its description.
310  */
asymmetric_key_match_preparse(struct key_match_data * match_data)311 static int asymmetric_key_match_preparse(struct key_match_data *match_data)
312 {
313 	struct asymmetric_key_id *match_id;
314 	const char *spec = match_data->raw_data;
315 	const char *id;
316 	bool (*cmp)(const struct key *, const struct key_match_data *) =
317 		asymmetric_key_cmp;
318 
319 	if (!spec || !*spec)
320 		return -EINVAL;
321 	if (spec[0] == 'i' &&
322 	    spec[1] == 'd' &&
323 	    spec[2] == ':') {
324 		id = spec + 3;
325 		cmp = asymmetric_key_cmp_partial;
326 	} else if (spec[0] == 'e' &&
327 		   spec[1] == 'x' &&
328 		   spec[2] == ':') {
329 		id = spec + 3;
330 	} else if (spec[0] == 'd' &&
331 		   spec[1] == 'n' &&
332 		   spec[2] == ':') {
333 		id = spec + 3;
334 		cmp = asymmetric_key_cmp_name;
335 	} else {
336 		goto default_match;
337 	}
338 
339 	match_id = asymmetric_key_hex_to_key_id(id);
340 	if (IS_ERR(match_id))
341 		return PTR_ERR(match_id);
342 
343 	match_data->preparsed = match_id;
344 	match_data->cmp = cmp;
345 	match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
346 	return 0;
347 
348 default_match:
349 	return 0;
350 }
351 
352 /*
353  * Free the preparsed the match criterion.
354  */
asymmetric_key_match_free(struct key_match_data * match_data)355 static void asymmetric_key_match_free(struct key_match_data *match_data)
356 {
357 	kfree(match_data->preparsed);
358 }
359 
360 /*
361  * Describe the asymmetric key
362  */
asymmetric_key_describe(const struct key * key,struct seq_file * m)363 static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
364 {
365 	const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
366 	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
367 	const struct asymmetric_key_id *kid;
368 	const unsigned char *p;
369 	int n;
370 
371 	seq_puts(m, key->description);
372 
373 	if (subtype) {
374 		seq_puts(m, ": ");
375 		subtype->describe(key, m);
376 
377 		if (kids && kids->id[1]) {
378 			kid = kids->id[1];
379 			seq_putc(m, ' ');
380 			n = kid->len;
381 			p = kid->data;
382 			if (n > 4) {
383 				p += n - 4;
384 				n = 4;
385 			}
386 			seq_printf(m, "%*phN", n, p);
387 		}
388 
389 		seq_puts(m, " [");
390 		/* put something here to indicate the key's capabilities */
391 		seq_putc(m, ']');
392 	}
393 }
394 
395 /*
396  * Preparse a asymmetric payload to get format the contents appropriately for the
397  * internal payload to cut down on the number of scans of the data performed.
398  *
399  * We also generate a proposed description from the contents of the key that
400  * can be used to name the key if the user doesn't want to provide one.
401  */
asymmetric_key_preparse(struct key_preparsed_payload * prep)402 static int asymmetric_key_preparse(struct key_preparsed_payload *prep)
403 {
404 	struct asymmetric_key_parser *parser;
405 	int ret;
406 
407 	pr_devel("==>%s()\n", __func__);
408 
409 	if (prep->datalen == 0)
410 		return -EINVAL;
411 
412 	down_read(&asymmetric_key_parsers_sem);
413 
414 	ret = -EBADMSG;
415 	list_for_each_entry(parser, &asymmetric_key_parsers, link) {
416 		pr_debug("Trying parser '%s'\n", parser->name);
417 
418 		ret = parser->parse(prep);
419 		if (ret != -EBADMSG) {
420 			pr_debug("Parser recognised the format (ret %d)\n",
421 				 ret);
422 			break;
423 		}
424 	}
425 
426 	up_read(&asymmetric_key_parsers_sem);
427 	pr_devel("<==%s() = %d\n", __func__, ret);
428 	return ret;
429 }
430 
431 /*
432  * Clean up the key ID list
433  */
asymmetric_key_free_kids(struct asymmetric_key_ids * kids)434 static void asymmetric_key_free_kids(struct asymmetric_key_ids *kids)
435 {
436 	int i;
437 
438 	if (kids) {
439 		for (i = 0; i < ARRAY_SIZE(kids->id); i++)
440 			kfree(kids->id[i]);
441 		kfree(kids);
442 	}
443 }
444 
445 /*
446  * Clean up the preparse data
447  */
asymmetric_key_free_preparse(struct key_preparsed_payload * prep)448 static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
449 {
450 	struct asymmetric_key_subtype *subtype = prep->payload.data[asym_subtype];
451 	struct asymmetric_key_ids *kids = prep->payload.data[asym_key_ids];
452 
453 	pr_devel("==>%s()\n", __func__);
454 
455 	if (subtype) {
456 		subtype->destroy(prep->payload.data[asym_crypto],
457 				 prep->payload.data[asym_auth]);
458 		module_put(subtype->owner);
459 	}
460 	asymmetric_key_free_kids(kids);
461 	kfree(prep->description);
462 }
463 
464 /*
465  * dispose of the data dangling from the corpse of a asymmetric key
466  */
asymmetric_key_destroy(struct key * key)467 static void asymmetric_key_destroy(struct key *key)
468 {
469 	struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
470 	struct asymmetric_key_ids *kids = key->payload.data[asym_key_ids];
471 	void *data = key->payload.data[asym_crypto];
472 	void *auth = key->payload.data[asym_auth];
473 
474 	key->payload.data[asym_crypto] = NULL;
475 	key->payload.data[asym_subtype] = NULL;
476 	key->payload.data[asym_key_ids] = NULL;
477 	key->payload.data[asym_auth] = NULL;
478 
479 	if (subtype) {
480 		subtype->destroy(data, auth);
481 		module_put(subtype->owner);
482 	}
483 
484 	asymmetric_key_free_kids(kids);
485 }
486 
asymmetric_restriction_alloc(key_restrict_link_func_t check,struct key * key)487 static struct key_restriction *asymmetric_restriction_alloc(
488 	key_restrict_link_func_t check,
489 	struct key *key)
490 {
491 	struct key_restriction *keyres =
492 		kzalloc(sizeof(struct key_restriction), GFP_KERNEL);
493 
494 	if (!keyres)
495 		return ERR_PTR(-ENOMEM);
496 
497 	keyres->check = check;
498 	keyres->key = key;
499 	keyres->keytype = &key_type_asymmetric;
500 
501 	return keyres;
502 }
503 
504 /*
505  * look up keyring restrict functions for asymmetric keys
506  */
asymmetric_lookup_restriction(const char * restriction)507 static struct key_restriction *asymmetric_lookup_restriction(
508 	const char *restriction)
509 {
510 	char *restrict_method;
511 	char *parse_buf;
512 	char *next;
513 	struct key_restriction *ret = ERR_PTR(-EINVAL);
514 
515 	if (strcmp("builtin_trusted", restriction) == 0)
516 		return asymmetric_restriction_alloc(
517 			restrict_link_by_builtin_trusted, NULL);
518 
519 	if (strcmp("builtin_and_secondary_trusted", restriction) == 0)
520 		return asymmetric_restriction_alloc(
521 			restrict_link_by_builtin_and_secondary_trusted, NULL);
522 
523 	parse_buf = kstrndup(restriction, PAGE_SIZE, GFP_KERNEL);
524 	if (!parse_buf)
525 		return ERR_PTR(-ENOMEM);
526 
527 	next = parse_buf;
528 	restrict_method = strsep(&next, ":");
529 
530 	if ((strcmp(restrict_method, "key_or_keyring") == 0) && next) {
531 		char *key_text;
532 		key_serial_t serial;
533 		struct key *key;
534 		key_restrict_link_func_t link_fn =
535 			restrict_link_by_key_or_keyring;
536 		bool allow_null_key = false;
537 
538 		key_text = strsep(&next, ":");
539 
540 		if (next) {
541 			if (strcmp(next, "chain") != 0)
542 				goto out;
543 
544 			link_fn = restrict_link_by_key_or_keyring_chain;
545 			allow_null_key = true;
546 		}
547 
548 		if (kstrtos32(key_text, 0, &serial) < 0)
549 			goto out;
550 
551 		if ((serial == 0) && allow_null_key) {
552 			key = NULL;
553 		} else {
554 			key = key_lookup(serial);
555 			if (IS_ERR(key)) {
556 				ret = ERR_CAST(key);
557 				goto out;
558 			}
559 		}
560 
561 		ret = asymmetric_restriction_alloc(link_fn, key);
562 		if (IS_ERR(ret))
563 			key_put(key);
564 	}
565 
566 out:
567 	kfree(parse_buf);
568 	return ret;
569 }
570 
asymmetric_key_eds_op(struct kernel_pkey_params * params,const void * in,void * out)571 int asymmetric_key_eds_op(struct kernel_pkey_params *params,
572 			  const void *in, void *out)
573 {
574 	const struct asymmetric_key_subtype *subtype;
575 	struct key *key = params->key;
576 	int ret;
577 
578 	pr_devel("==>%s()\n", __func__);
579 
580 	if (key->type != &key_type_asymmetric)
581 		return -EINVAL;
582 	subtype = asymmetric_key_subtype(key);
583 	if (!subtype ||
584 	    !key->payload.data[0])
585 		return -EINVAL;
586 	if (!subtype->eds_op)
587 		return -ENOTSUPP;
588 
589 	ret = subtype->eds_op(params, in, out);
590 
591 	pr_devel("<==%s() = %d\n", __func__, ret);
592 	return ret;
593 }
594 
asymmetric_key_verify_signature(struct kernel_pkey_params * params,const void * in,const void * in2)595 static int asymmetric_key_verify_signature(struct kernel_pkey_params *params,
596 					   const void *in, const void *in2)
597 {
598 	struct public_key_signature sig = {
599 		.s_size		= params->in2_len,
600 		.digest_size	= params->in_len,
601 		.encoding	= params->encoding,
602 		.hash_algo	= params->hash_algo,
603 		.digest		= (void *)in,
604 		.s		= (void *)in2,
605 	};
606 
607 	return verify_signature(params->key, &sig);
608 }
609 
610 struct key_type key_type_asymmetric = {
611 	.name			= "asymmetric",
612 	.preparse		= asymmetric_key_preparse,
613 	.free_preparse		= asymmetric_key_free_preparse,
614 	.instantiate		= generic_key_instantiate,
615 	.match_preparse		= asymmetric_key_match_preparse,
616 	.match_free		= asymmetric_key_match_free,
617 	.destroy		= asymmetric_key_destroy,
618 	.describe		= asymmetric_key_describe,
619 	.lookup_restriction	= asymmetric_lookup_restriction,
620 	.asym_query		= query_asymmetric_key,
621 	.asym_eds_op		= asymmetric_key_eds_op,
622 	.asym_verify_signature	= asymmetric_key_verify_signature,
623 };
624 EXPORT_SYMBOL_GPL(key_type_asymmetric);
625 
626 /**
627  * register_asymmetric_key_parser - Register a asymmetric key blob parser
628  * @parser: The parser to register
629  */
register_asymmetric_key_parser(struct asymmetric_key_parser * parser)630 int register_asymmetric_key_parser(struct asymmetric_key_parser *parser)
631 {
632 	struct asymmetric_key_parser *cursor;
633 	int ret;
634 
635 	down_write(&asymmetric_key_parsers_sem);
636 
637 	list_for_each_entry(cursor, &asymmetric_key_parsers, link) {
638 		if (strcmp(cursor->name, parser->name) == 0) {
639 			pr_err("Asymmetric key parser '%s' already registered\n",
640 			       parser->name);
641 			ret = -EEXIST;
642 			goto out;
643 		}
644 	}
645 
646 	list_add_tail(&parser->link, &asymmetric_key_parsers);
647 
648 	pr_notice("Asymmetric key parser '%s' registered\n", parser->name);
649 	ret = 0;
650 
651 out:
652 	up_write(&asymmetric_key_parsers_sem);
653 	return ret;
654 }
655 EXPORT_SYMBOL_GPL(register_asymmetric_key_parser);
656 
657 /**
658  * unregister_asymmetric_key_parser - Unregister a asymmetric key blob parser
659  * @parser: The parser to unregister
660  */
unregister_asymmetric_key_parser(struct asymmetric_key_parser * parser)661 void unregister_asymmetric_key_parser(struct asymmetric_key_parser *parser)
662 {
663 	down_write(&asymmetric_key_parsers_sem);
664 	list_del(&parser->link);
665 	up_write(&asymmetric_key_parsers_sem);
666 
667 	pr_notice("Asymmetric key parser '%s' unregistered\n", parser->name);
668 }
669 EXPORT_SYMBOL_GPL(unregister_asymmetric_key_parser);
670 
671 /*
672  * Module stuff
673  */
asymmetric_key_init(void)674 static int __init asymmetric_key_init(void)
675 {
676 	return register_key_type(&key_type_asymmetric);
677 }
678 
asymmetric_key_cleanup(void)679 static void __exit asymmetric_key_cleanup(void)
680 {
681 	unregister_key_type(&key_type_asymmetric);
682 }
683 
684 module_init(asymmetric_key_init);
685 module_exit(asymmetric_key_cleanup);
686