1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* Basic authentication token and access key management |
3 | * |
4 | * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved. |
5 | * Written by David Howells (dhowells@redhat.com) |
6 | */ |
7 | |
8 | #include <linux/export.h> |
9 | #include <linux/init.h> |
10 | #include <linux/poison.h> |
11 | #include <linux/sched.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/security.h> |
14 | #include <linux/workqueue.h> |
15 | #include <linux/random.h> |
16 | #include <linux/err.h> |
17 | #include "internal.h" |
18 | |
19 | struct kmem_cache *key_jar; |
20 | struct rb_root key_serial_tree; /* tree of keys indexed by serial */ |
21 | DEFINE_SPINLOCK(key_serial_lock); |
22 | |
23 | struct rb_root key_user_tree; /* tree of quota records indexed by UID */ |
24 | DEFINE_SPINLOCK(key_user_lock); |
25 | |
26 | unsigned int key_quota_root_maxkeys = 1000000; /* root's key count quota */ |
27 | unsigned int key_quota_root_maxbytes = 25000000; /* root's key space quota */ |
28 | unsigned int key_quota_maxkeys = 200; /* general key count quota */ |
29 | unsigned int key_quota_maxbytes = 20000; /* general key space quota */ |
30 | |
31 | static LIST_HEAD(key_types_list); |
32 | static DECLARE_RWSEM(key_types_sem); |
33 | |
34 | /* We serialise key instantiation and link */ |
35 | DEFINE_MUTEX(key_construction_mutex); |
36 | |
37 | #ifdef KEY_DEBUGGING |
38 | void __key_check(const struct key *key) |
39 | { |
40 | printk("__key_check: key %p {%08x} should be {%08x}\n" , |
41 | key, key->magic, KEY_DEBUG_MAGIC); |
42 | BUG(); |
43 | } |
44 | #endif |
45 | |
46 | /* |
47 | * Get the key quota record for a user, allocating a new record if one doesn't |
48 | * already exist. |
49 | */ |
50 | struct key_user *key_user_lookup(kuid_t uid) |
51 | { |
52 | struct key_user *candidate = NULL, *user; |
53 | struct rb_node *parent, **p; |
54 | |
55 | try_again: |
56 | parent = NULL; |
57 | p = &key_user_tree.rb_node; |
58 | spin_lock(lock: &key_user_lock); |
59 | |
60 | /* search the tree for a user record with a matching UID */ |
61 | while (*p) { |
62 | parent = *p; |
63 | user = rb_entry(parent, struct key_user, node); |
64 | |
65 | if (uid_lt(left: uid, right: user->uid)) |
66 | p = &(*p)->rb_left; |
67 | else if (uid_gt(left: uid, right: user->uid)) |
68 | p = &(*p)->rb_right; |
69 | else |
70 | goto found; |
71 | } |
72 | |
73 | /* if we get here, we failed to find a match in the tree */ |
74 | if (!candidate) { |
75 | /* allocate a candidate user record if we don't already have |
76 | * one */ |
77 | spin_unlock(lock: &key_user_lock); |
78 | |
79 | user = NULL; |
80 | candidate = kmalloc(size: sizeof(struct key_user), GFP_KERNEL); |
81 | if (unlikely(!candidate)) |
82 | goto out; |
83 | |
84 | /* the allocation may have scheduled, so we need to repeat the |
85 | * search lest someone else added the record whilst we were |
86 | * asleep */ |
87 | goto try_again; |
88 | } |
89 | |
90 | /* if we get here, then the user record still hadn't appeared on the |
91 | * second pass - so we use the candidate record */ |
92 | refcount_set(r: &candidate->usage, n: 1); |
93 | atomic_set(v: &candidate->nkeys, i: 0); |
94 | atomic_set(v: &candidate->nikeys, i: 0); |
95 | candidate->uid = uid; |
96 | candidate->qnkeys = 0; |
97 | candidate->qnbytes = 0; |
98 | spin_lock_init(&candidate->lock); |
99 | mutex_init(&candidate->cons_lock); |
100 | |
101 | rb_link_node(node: &candidate->node, parent, rb_link: p); |
102 | rb_insert_color(&candidate->node, &key_user_tree); |
103 | spin_unlock(lock: &key_user_lock); |
104 | user = candidate; |
105 | goto out; |
106 | |
107 | /* okay - we found a user record for this UID */ |
108 | found: |
109 | refcount_inc(r: &user->usage); |
110 | spin_unlock(lock: &key_user_lock); |
111 | kfree(objp: candidate); |
112 | out: |
113 | return user; |
114 | } |
115 | |
116 | /* |
117 | * Dispose of a user structure |
118 | */ |
119 | void key_user_put(struct key_user *user) |
120 | { |
121 | if (refcount_dec_and_lock(r: &user->usage, lock: &key_user_lock)) { |
122 | rb_erase(&user->node, &key_user_tree); |
123 | spin_unlock(lock: &key_user_lock); |
124 | |
125 | kfree(objp: user); |
126 | } |
127 | } |
128 | |
129 | /* |
130 | * Allocate a serial number for a key. These are assigned randomly to avoid |
131 | * security issues through covert channel problems. |
132 | */ |
133 | static inline void key_alloc_serial(struct key *key) |
134 | { |
135 | struct rb_node *parent, **p; |
136 | struct key *xkey; |
137 | |
138 | /* propose a random serial number and look for a hole for it in the |
139 | * serial number tree */ |
140 | do { |
141 | get_random_bytes(buf: &key->serial, len: sizeof(key->serial)); |
142 | |
143 | key->serial >>= 1; /* negative numbers are not permitted */ |
144 | } while (key->serial < 3); |
145 | |
146 | spin_lock(lock: &key_serial_lock); |
147 | |
148 | attempt_insertion: |
149 | parent = NULL; |
150 | p = &key_serial_tree.rb_node; |
151 | |
152 | while (*p) { |
153 | parent = *p; |
154 | xkey = rb_entry(parent, struct key, serial_node); |
155 | |
156 | if (key->serial < xkey->serial) |
157 | p = &(*p)->rb_left; |
158 | else if (key->serial > xkey->serial) |
159 | p = &(*p)->rb_right; |
160 | else |
161 | goto serial_exists; |
162 | } |
163 | |
164 | /* we've found a suitable hole - arrange for this key to occupy it */ |
165 | rb_link_node(node: &key->serial_node, parent, rb_link: p); |
166 | rb_insert_color(&key->serial_node, &key_serial_tree); |
167 | |
168 | spin_unlock(lock: &key_serial_lock); |
169 | return; |
170 | |
171 | /* we found a key with the proposed serial number - walk the tree from |
172 | * that point looking for the next unused serial number */ |
173 | serial_exists: |
174 | for (;;) { |
175 | key->serial++; |
176 | if (key->serial < 3) { |
177 | key->serial = 3; |
178 | goto attempt_insertion; |
179 | } |
180 | |
181 | parent = rb_next(parent); |
182 | if (!parent) |
183 | goto attempt_insertion; |
184 | |
185 | xkey = rb_entry(parent, struct key, serial_node); |
186 | if (key->serial < xkey->serial) |
187 | goto attempt_insertion; |
188 | } |
189 | } |
190 | |
191 | /** |
192 | * key_alloc - Allocate a key of the specified type. |
193 | * @type: The type of key to allocate. |
194 | * @desc: The key description to allow the key to be searched out. |
195 | * @uid: The owner of the new key. |
196 | * @gid: The group ID for the new key's group permissions. |
197 | * @cred: The credentials specifying UID namespace. |
198 | * @perm: The permissions mask of the new key. |
199 | * @flags: Flags specifying quota properties. |
200 | * @restrict_link: Optional link restriction for new keyrings. |
201 | * |
202 | * Allocate a key of the specified type with the attributes given. The key is |
203 | * returned in an uninstantiated state and the caller needs to instantiate the |
204 | * key before returning. |
205 | * |
206 | * The restrict_link structure (if not NULL) will be freed when the |
207 | * keyring is destroyed, so it must be dynamically allocated. |
208 | * |
209 | * The user's key count quota is updated to reflect the creation of the key and |
210 | * the user's key data quota has the default for the key type reserved. The |
211 | * instantiation function should amend this as necessary. If insufficient |
212 | * quota is available, -EDQUOT will be returned. |
213 | * |
214 | * The LSM security modules can prevent a key being created, in which case |
215 | * -EACCES will be returned. |
216 | * |
217 | * Returns a pointer to the new key if successful and an error code otherwise. |
218 | * |
219 | * Note that the caller needs to ensure the key type isn't uninstantiated. |
220 | * Internally this can be done by locking key_types_sem. Externally, this can |
221 | * be done by either never unregistering the key type, or making sure |
222 | * key_alloc() calls don't race with module unloading. |
223 | */ |
224 | struct key *key_alloc(struct key_type *type, const char *desc, |
225 | kuid_t uid, kgid_t gid, const struct cred *cred, |
226 | key_perm_t perm, unsigned long flags, |
227 | struct key_restriction *restrict_link) |
228 | { |
229 | struct key_user *user = NULL; |
230 | struct key *key; |
231 | size_t desclen, quotalen; |
232 | int ret; |
233 | |
234 | key = ERR_PTR(error: -EINVAL); |
235 | if (!desc || !*desc) |
236 | goto error; |
237 | |
238 | if (type->vet_description) { |
239 | ret = type->vet_description(desc); |
240 | if (ret < 0) { |
241 | key = ERR_PTR(error: ret); |
242 | goto error; |
243 | } |
244 | } |
245 | |
246 | desclen = strlen(desc); |
247 | quotalen = desclen + 1 + type->def_datalen; |
248 | |
249 | /* get hold of the key tracking for this user */ |
250 | user = key_user_lookup(uid); |
251 | if (!user) |
252 | goto no_memory_1; |
253 | |
254 | /* check that the user's quota permits allocation of another key and |
255 | * its description */ |
256 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
257 | unsigned maxkeys = uid_eq(left: uid, GLOBAL_ROOT_UID) ? |
258 | key_quota_root_maxkeys : key_quota_maxkeys; |
259 | unsigned maxbytes = uid_eq(left: uid, GLOBAL_ROOT_UID) ? |
260 | key_quota_root_maxbytes : key_quota_maxbytes; |
261 | |
262 | spin_lock(lock: &user->lock); |
263 | if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { |
264 | if (user->qnkeys + 1 > maxkeys || |
265 | user->qnbytes + quotalen > maxbytes || |
266 | user->qnbytes + quotalen < user->qnbytes) |
267 | goto no_quota; |
268 | } |
269 | |
270 | user->qnkeys++; |
271 | user->qnbytes += quotalen; |
272 | spin_unlock(lock: &user->lock); |
273 | } |
274 | |
275 | /* allocate and initialise the key and its description */ |
276 | key = kmem_cache_zalloc(k: key_jar, GFP_KERNEL); |
277 | if (!key) |
278 | goto no_memory_2; |
279 | |
280 | key->index_key.desc_len = desclen; |
281 | key->index_key.description = kmemdup(p: desc, size: desclen + 1, GFP_KERNEL); |
282 | if (!key->index_key.description) |
283 | goto no_memory_3; |
284 | key->index_key.type = type; |
285 | key_set_index_key(index_key: &key->index_key); |
286 | |
287 | refcount_set(r: &key->usage, n: 1); |
288 | init_rwsem(&key->sem); |
289 | lockdep_set_class(&key->sem, &type->lock_class); |
290 | key->user = user; |
291 | key->quotalen = quotalen; |
292 | key->datalen = type->def_datalen; |
293 | key->uid = uid; |
294 | key->gid = gid; |
295 | key->perm = perm; |
296 | key->expiry = TIME64_MAX; |
297 | key->restrict_link = restrict_link; |
298 | key->last_used_at = ktime_get_real_seconds(); |
299 | |
300 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) |
301 | key->flags |= 1 << KEY_FLAG_IN_QUOTA; |
302 | if (flags & KEY_ALLOC_BUILT_IN) |
303 | key->flags |= 1 << KEY_FLAG_BUILTIN; |
304 | if (flags & KEY_ALLOC_UID_KEYRING) |
305 | key->flags |= 1 << KEY_FLAG_UID_KEYRING; |
306 | if (flags & KEY_ALLOC_SET_KEEP) |
307 | key->flags |= 1 << KEY_FLAG_KEEP; |
308 | |
309 | #ifdef KEY_DEBUGGING |
310 | key->magic = KEY_DEBUG_MAGIC; |
311 | #endif |
312 | |
313 | /* let the security module know about the key */ |
314 | ret = security_key_alloc(key, cred, flags); |
315 | if (ret < 0) |
316 | goto security_error; |
317 | |
318 | /* publish the key by giving it a serial number */ |
319 | refcount_inc(r: &key->domain_tag->usage); |
320 | atomic_inc(v: &user->nkeys); |
321 | key_alloc_serial(key); |
322 | |
323 | error: |
324 | return key; |
325 | |
326 | security_error: |
327 | kfree(objp: key->description); |
328 | kmem_cache_free(s: key_jar, objp: key); |
329 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
330 | spin_lock(lock: &user->lock); |
331 | user->qnkeys--; |
332 | user->qnbytes -= quotalen; |
333 | spin_unlock(lock: &user->lock); |
334 | } |
335 | key_user_put(user); |
336 | key = ERR_PTR(error: ret); |
337 | goto error; |
338 | |
339 | no_memory_3: |
340 | kmem_cache_free(s: key_jar, objp: key); |
341 | no_memory_2: |
342 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
343 | spin_lock(lock: &user->lock); |
344 | user->qnkeys--; |
345 | user->qnbytes -= quotalen; |
346 | spin_unlock(lock: &user->lock); |
347 | } |
348 | key_user_put(user); |
349 | no_memory_1: |
350 | key = ERR_PTR(error: -ENOMEM); |
351 | goto error; |
352 | |
353 | no_quota: |
354 | spin_unlock(lock: &user->lock); |
355 | key_user_put(user); |
356 | key = ERR_PTR(error: -EDQUOT); |
357 | goto error; |
358 | } |
359 | EXPORT_SYMBOL(key_alloc); |
360 | |
361 | /** |
362 | * key_payload_reserve - Adjust data quota reservation for the key's payload |
363 | * @key: The key to make the reservation for. |
364 | * @datalen: The amount of data payload the caller now wants. |
365 | * |
366 | * Adjust the amount of the owning user's key data quota that a key reserves. |
367 | * If the amount is increased, then -EDQUOT may be returned if there isn't |
368 | * enough free quota available. |
369 | * |
370 | * If successful, 0 is returned. |
371 | */ |
372 | int key_payload_reserve(struct key *key, size_t datalen) |
373 | { |
374 | int delta = (int)datalen - key->datalen; |
375 | int ret = 0; |
376 | |
377 | key_check(key); |
378 | |
379 | /* contemplate the quota adjustment */ |
380 | if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) { |
381 | unsigned maxbytes = uid_eq(left: key->user->uid, GLOBAL_ROOT_UID) ? |
382 | key_quota_root_maxbytes : key_quota_maxbytes; |
383 | |
384 | spin_lock(lock: &key->user->lock); |
385 | |
386 | if (delta > 0 && |
387 | (key->user->qnbytes + delta > maxbytes || |
388 | key->user->qnbytes + delta < key->user->qnbytes)) { |
389 | ret = -EDQUOT; |
390 | } |
391 | else { |
392 | key->user->qnbytes += delta; |
393 | key->quotalen += delta; |
394 | } |
395 | spin_unlock(lock: &key->user->lock); |
396 | } |
397 | |
398 | /* change the recorded data length if that didn't generate an error */ |
399 | if (ret == 0) |
400 | key->datalen = datalen; |
401 | |
402 | return ret; |
403 | } |
404 | EXPORT_SYMBOL(key_payload_reserve); |
405 | |
406 | /* |
407 | * Change the key state to being instantiated. |
408 | */ |
409 | static void mark_key_instantiated(struct key *key, int reject_error) |
410 | { |
411 | /* Commit the payload before setting the state; barrier versus |
412 | * key_read_state(). |
413 | */ |
414 | smp_store_release(&key->state, |
415 | (reject_error < 0) ? reject_error : KEY_IS_POSITIVE); |
416 | } |
417 | |
418 | /* |
419 | * Instantiate a key and link it into the target keyring atomically. Must be |
420 | * called with the target keyring's semaphore writelocked. The target key's |
421 | * semaphore need not be locked as instantiation is serialised by |
422 | * key_construction_mutex. |
423 | */ |
424 | static int __key_instantiate_and_link(struct key *key, |
425 | struct key_preparsed_payload *prep, |
426 | struct key *keyring, |
427 | struct key *authkey, |
428 | struct assoc_array_edit **_edit) |
429 | { |
430 | int ret, awaken; |
431 | |
432 | key_check(key); |
433 | key_check(keyring); |
434 | |
435 | awaken = 0; |
436 | ret = -EBUSY; |
437 | |
438 | mutex_lock(&key_construction_mutex); |
439 | |
440 | /* can't instantiate twice */ |
441 | if (key->state == KEY_IS_UNINSTANTIATED) { |
442 | /* instantiate the key */ |
443 | ret = key->type->instantiate(key, prep); |
444 | |
445 | if (ret == 0) { |
446 | /* mark the key as being instantiated */ |
447 | atomic_inc(v: &key->user->nikeys); |
448 | mark_key_instantiated(key, reject_error: 0); |
449 | notify_key(key, subtype: NOTIFY_KEY_INSTANTIATED, aux: 0); |
450 | |
451 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, addr: &key->flags)) |
452 | awaken = 1; |
453 | |
454 | /* and link it into the destination keyring */ |
455 | if (keyring) { |
456 | if (test_bit(KEY_FLAG_KEEP, &keyring->flags)) |
457 | set_bit(KEY_FLAG_KEEP, addr: &key->flags); |
458 | |
459 | __key_link(keyring, key, _edit); |
460 | } |
461 | |
462 | /* disable the authorisation key */ |
463 | if (authkey) |
464 | key_invalidate(key: authkey); |
465 | |
466 | key_set_expiry(key, expiry: prep->expiry); |
467 | } |
468 | } |
469 | |
470 | mutex_unlock(lock: &key_construction_mutex); |
471 | |
472 | /* wake up anyone waiting for a key to be constructed */ |
473 | if (awaken) |
474 | wake_up_bit(word: &key->flags, KEY_FLAG_USER_CONSTRUCT); |
475 | |
476 | return ret; |
477 | } |
478 | |
479 | /** |
480 | * key_instantiate_and_link - Instantiate a key and link it into the keyring. |
481 | * @key: The key to instantiate. |
482 | * @data: The data to use to instantiate the keyring. |
483 | * @datalen: The length of @data. |
484 | * @keyring: Keyring to create a link in on success (or NULL). |
485 | * @authkey: The authorisation token permitting instantiation. |
486 | * |
487 | * Instantiate a key that's in the uninstantiated state using the provided data |
488 | * and, if successful, link it in to the destination keyring if one is |
489 | * supplied. |
490 | * |
491 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
492 | * waiting for the key is woken up. If the key was already instantiated, |
493 | * -EBUSY will be returned. |
494 | */ |
495 | int key_instantiate_and_link(struct key *key, |
496 | const void *data, |
497 | size_t datalen, |
498 | struct key *keyring, |
499 | struct key *authkey) |
500 | { |
501 | struct key_preparsed_payload prep; |
502 | struct assoc_array_edit *edit = NULL; |
503 | int ret; |
504 | |
505 | memset(&prep, 0, sizeof(prep)); |
506 | prep.orig_description = key->description; |
507 | prep.data = data; |
508 | prep.datalen = datalen; |
509 | prep.quotalen = key->type->def_datalen; |
510 | prep.expiry = TIME64_MAX; |
511 | if (key->type->preparse) { |
512 | ret = key->type->preparse(&prep); |
513 | if (ret < 0) |
514 | goto error; |
515 | } |
516 | |
517 | if (keyring) { |
518 | ret = __key_link_lock(keyring, index_key: &key->index_key); |
519 | if (ret < 0) |
520 | goto error; |
521 | |
522 | ret = __key_link_begin(keyring, index_key: &key->index_key, edit: &edit); |
523 | if (ret < 0) |
524 | goto error_link_end; |
525 | |
526 | if (keyring->restrict_link && keyring->restrict_link->check) { |
527 | struct key_restriction *keyres = keyring->restrict_link; |
528 | |
529 | ret = keyres->check(keyring, key->type, &prep.payload, |
530 | keyres->key); |
531 | if (ret < 0) |
532 | goto error_link_end; |
533 | } |
534 | } |
535 | |
536 | ret = __key_instantiate_and_link(key, prep: &prep, keyring, authkey, edit: &edit); |
537 | |
538 | error_link_end: |
539 | if (keyring) |
540 | __key_link_end(keyring, index_key: &key->index_key, edit); |
541 | |
542 | error: |
543 | if (key->type->preparse) |
544 | key->type->free_preparse(&prep); |
545 | return ret; |
546 | } |
547 | |
548 | EXPORT_SYMBOL(key_instantiate_and_link); |
549 | |
550 | /** |
551 | * key_reject_and_link - Negatively instantiate a key and link it into the keyring. |
552 | * @key: The key to instantiate. |
553 | * @timeout: The timeout on the negative key. |
554 | * @error: The error to return when the key is hit. |
555 | * @keyring: Keyring to create a link in on success (or NULL). |
556 | * @authkey: The authorisation token permitting instantiation. |
557 | * |
558 | * Negatively instantiate a key that's in the uninstantiated state and, if |
559 | * successful, set its timeout and stored error and link it in to the |
560 | * destination keyring if one is supplied. The key and any links to the key |
561 | * will be automatically garbage collected after the timeout expires. |
562 | * |
563 | * Negative keys are used to rate limit repeated request_key() calls by causing |
564 | * them to return the stored error code (typically ENOKEY) until the negative |
565 | * key expires. |
566 | * |
567 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
568 | * waiting for the key is woken up. If the key was already instantiated, |
569 | * -EBUSY will be returned. |
570 | */ |
571 | int key_reject_and_link(struct key *key, |
572 | unsigned timeout, |
573 | unsigned error, |
574 | struct key *keyring, |
575 | struct key *authkey) |
576 | { |
577 | struct assoc_array_edit *edit = NULL; |
578 | int ret, awaken, link_ret = 0; |
579 | |
580 | key_check(key); |
581 | key_check(keyring); |
582 | |
583 | awaken = 0; |
584 | ret = -EBUSY; |
585 | |
586 | if (keyring) { |
587 | if (keyring->restrict_link) |
588 | return -EPERM; |
589 | |
590 | link_ret = __key_link_lock(keyring, index_key: &key->index_key); |
591 | if (link_ret == 0) { |
592 | link_ret = __key_link_begin(keyring, index_key: &key->index_key, edit: &edit); |
593 | if (link_ret < 0) |
594 | __key_link_end(keyring, index_key: &key->index_key, edit); |
595 | } |
596 | } |
597 | |
598 | mutex_lock(&key_construction_mutex); |
599 | |
600 | /* can't instantiate twice */ |
601 | if (key->state == KEY_IS_UNINSTANTIATED) { |
602 | /* mark the key as being negatively instantiated */ |
603 | atomic_inc(v: &key->user->nikeys); |
604 | mark_key_instantiated(key, reject_error: -error); |
605 | notify_key(key, subtype: NOTIFY_KEY_INSTANTIATED, aux: -error); |
606 | key_set_expiry(key, expiry: ktime_get_real_seconds() + timeout); |
607 | |
608 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, addr: &key->flags)) |
609 | awaken = 1; |
610 | |
611 | ret = 0; |
612 | |
613 | /* and link it into the destination keyring */ |
614 | if (keyring && link_ret == 0) |
615 | __key_link(keyring, key, edit: &edit); |
616 | |
617 | /* disable the authorisation key */ |
618 | if (authkey) |
619 | key_invalidate(key: authkey); |
620 | } |
621 | |
622 | mutex_unlock(lock: &key_construction_mutex); |
623 | |
624 | if (keyring && link_ret == 0) |
625 | __key_link_end(keyring, index_key: &key->index_key, edit); |
626 | |
627 | /* wake up anyone waiting for a key to be constructed */ |
628 | if (awaken) |
629 | wake_up_bit(word: &key->flags, KEY_FLAG_USER_CONSTRUCT); |
630 | |
631 | return ret == 0 ? link_ret : ret; |
632 | } |
633 | EXPORT_SYMBOL(key_reject_and_link); |
634 | |
635 | /** |
636 | * key_put - Discard a reference to a key. |
637 | * @key: The key to discard a reference from. |
638 | * |
639 | * Discard a reference to a key, and when all the references are gone, we |
640 | * schedule the cleanup task to come and pull it out of the tree in process |
641 | * context at some later time. |
642 | */ |
643 | void key_put(struct key *key) |
644 | { |
645 | if (key) { |
646 | key_check(key); |
647 | |
648 | if (refcount_dec_and_test(r: &key->usage)) |
649 | schedule_work(work: &key_gc_work); |
650 | } |
651 | } |
652 | EXPORT_SYMBOL(key_put); |
653 | |
654 | /* |
655 | * Find a key by its serial number. |
656 | */ |
657 | struct key *key_lookup(key_serial_t id) |
658 | { |
659 | struct rb_node *n; |
660 | struct key *key; |
661 | |
662 | spin_lock(lock: &key_serial_lock); |
663 | |
664 | /* search the tree for the specified key */ |
665 | n = key_serial_tree.rb_node; |
666 | while (n) { |
667 | key = rb_entry(n, struct key, serial_node); |
668 | |
669 | if (id < key->serial) |
670 | n = n->rb_left; |
671 | else if (id > key->serial) |
672 | n = n->rb_right; |
673 | else |
674 | goto found; |
675 | } |
676 | |
677 | not_found: |
678 | key = ERR_PTR(error: -ENOKEY); |
679 | goto error; |
680 | |
681 | found: |
682 | /* A key is allowed to be looked up only if someone still owns a |
683 | * reference to it - otherwise it's awaiting the gc. |
684 | */ |
685 | if (!refcount_inc_not_zero(r: &key->usage)) |
686 | goto not_found; |
687 | |
688 | error: |
689 | spin_unlock(lock: &key_serial_lock); |
690 | return key; |
691 | } |
692 | EXPORT_SYMBOL(key_lookup); |
693 | |
694 | /* |
695 | * Find and lock the specified key type against removal. |
696 | * |
697 | * We return with the sem read-locked if successful. If the type wasn't |
698 | * available -ENOKEY is returned instead. |
699 | */ |
700 | struct key_type *key_type_lookup(const char *type) |
701 | { |
702 | struct key_type *ktype; |
703 | |
704 | down_read(sem: &key_types_sem); |
705 | |
706 | /* look up the key type to see if it's one of the registered kernel |
707 | * types */ |
708 | list_for_each_entry(ktype, &key_types_list, link) { |
709 | if (strcmp(ktype->name, type) == 0) |
710 | goto found_kernel_type; |
711 | } |
712 | |
713 | up_read(sem: &key_types_sem); |
714 | ktype = ERR_PTR(error: -ENOKEY); |
715 | |
716 | found_kernel_type: |
717 | return ktype; |
718 | } |
719 | |
720 | void key_set_timeout(struct key *key, unsigned timeout) |
721 | { |
722 | time64_t expiry = TIME64_MAX; |
723 | |
724 | /* make the changes with the locks held to prevent races */ |
725 | down_write(sem: &key->sem); |
726 | |
727 | if (timeout > 0) |
728 | expiry = ktime_get_real_seconds() + timeout; |
729 | key_set_expiry(key, expiry); |
730 | |
731 | up_write(sem: &key->sem); |
732 | } |
733 | EXPORT_SYMBOL_GPL(key_set_timeout); |
734 | |
735 | /* |
736 | * Unlock a key type locked by key_type_lookup(). |
737 | */ |
738 | void key_type_put(struct key_type *ktype) |
739 | { |
740 | up_read(sem: &key_types_sem); |
741 | } |
742 | |
743 | /* |
744 | * Attempt to update an existing key. |
745 | * |
746 | * The key is given to us with an incremented refcount that we need to discard |
747 | * if we get an error. |
748 | */ |
749 | static inline key_ref_t __key_update(key_ref_t key_ref, |
750 | struct key_preparsed_payload *prep) |
751 | { |
752 | struct key *key = key_ref_to_ptr(key_ref); |
753 | int ret; |
754 | |
755 | /* need write permission on the key to update it */ |
756 | ret = key_permission(key_ref, need_perm: KEY_NEED_WRITE); |
757 | if (ret < 0) |
758 | goto error; |
759 | |
760 | ret = -EEXIST; |
761 | if (!key->type->update) |
762 | goto error; |
763 | |
764 | down_write(sem: &key->sem); |
765 | |
766 | ret = key->type->update(key, prep); |
767 | if (ret == 0) { |
768 | /* Updating a negative key positively instantiates it */ |
769 | mark_key_instantiated(key, reject_error: 0); |
770 | notify_key(key, subtype: NOTIFY_KEY_UPDATED, aux: 0); |
771 | } |
772 | |
773 | up_write(sem: &key->sem); |
774 | |
775 | if (ret < 0) |
776 | goto error; |
777 | out: |
778 | return key_ref; |
779 | |
780 | error: |
781 | key_put(key); |
782 | key_ref = ERR_PTR(error: ret); |
783 | goto out; |
784 | } |
785 | |
786 | /* |
787 | * Create or potentially update a key. The combined logic behind |
788 | * key_create_or_update() and key_create() |
789 | */ |
790 | static key_ref_t __key_create_or_update(key_ref_t keyring_ref, |
791 | const char *type, |
792 | const char *description, |
793 | const void *payload, |
794 | size_t plen, |
795 | key_perm_t perm, |
796 | unsigned long flags, |
797 | bool allow_update) |
798 | { |
799 | struct keyring_index_key index_key = { |
800 | .description = description, |
801 | }; |
802 | struct key_preparsed_payload prep; |
803 | struct assoc_array_edit *edit = NULL; |
804 | const struct cred *cred = current_cred(); |
805 | struct key *keyring, *key = NULL; |
806 | key_ref_t key_ref; |
807 | int ret; |
808 | struct key_restriction *restrict_link = NULL; |
809 | |
810 | /* look up the key type to see if it's one of the registered kernel |
811 | * types */ |
812 | index_key.type = key_type_lookup(type); |
813 | if (IS_ERR(ptr: index_key.type)) { |
814 | key_ref = ERR_PTR(error: -ENODEV); |
815 | goto error; |
816 | } |
817 | |
818 | key_ref = ERR_PTR(error: -EINVAL); |
819 | if (!index_key.type->instantiate || |
820 | (!index_key.description && !index_key.type->preparse)) |
821 | goto error_put_type; |
822 | |
823 | keyring = key_ref_to_ptr(key_ref: keyring_ref); |
824 | |
825 | key_check(keyring); |
826 | |
827 | if (!(flags & KEY_ALLOC_BYPASS_RESTRICTION)) |
828 | restrict_link = keyring->restrict_link; |
829 | |
830 | key_ref = ERR_PTR(error: -ENOTDIR); |
831 | if (keyring->type != &key_type_keyring) |
832 | goto error_put_type; |
833 | |
834 | memset(&prep, 0, sizeof(prep)); |
835 | prep.orig_description = description; |
836 | prep.data = payload; |
837 | prep.datalen = plen; |
838 | prep.quotalen = index_key.type->def_datalen; |
839 | prep.expiry = TIME64_MAX; |
840 | if (index_key.type->preparse) { |
841 | ret = index_key.type->preparse(&prep); |
842 | if (ret < 0) { |
843 | key_ref = ERR_PTR(error: ret); |
844 | goto error_free_prep; |
845 | } |
846 | if (!index_key.description) |
847 | index_key.description = prep.description; |
848 | key_ref = ERR_PTR(error: -EINVAL); |
849 | if (!index_key.description) |
850 | goto error_free_prep; |
851 | } |
852 | index_key.desc_len = strlen(index_key.description); |
853 | key_set_index_key(index_key: &index_key); |
854 | |
855 | ret = __key_link_lock(keyring, index_key: &index_key); |
856 | if (ret < 0) { |
857 | key_ref = ERR_PTR(error: ret); |
858 | goto error_free_prep; |
859 | } |
860 | |
861 | ret = __key_link_begin(keyring, index_key: &index_key, edit: &edit); |
862 | if (ret < 0) { |
863 | key_ref = ERR_PTR(error: ret); |
864 | goto error_link_end; |
865 | } |
866 | |
867 | if (restrict_link && restrict_link->check) { |
868 | ret = restrict_link->check(keyring, index_key.type, |
869 | &prep.payload, restrict_link->key); |
870 | if (ret < 0) { |
871 | key_ref = ERR_PTR(error: ret); |
872 | goto error_link_end; |
873 | } |
874 | } |
875 | |
876 | /* if we're going to allocate a new key, we're going to have |
877 | * to modify the keyring */ |
878 | ret = key_permission(key_ref: keyring_ref, need_perm: KEY_NEED_WRITE); |
879 | if (ret < 0) { |
880 | key_ref = ERR_PTR(error: ret); |
881 | goto error_link_end; |
882 | } |
883 | |
884 | /* if it's requested and possible to update this type of key, search |
885 | * for an existing key of the same type and description in the |
886 | * destination keyring and update that instead if possible |
887 | */ |
888 | if (allow_update) { |
889 | if (index_key.type->update) { |
890 | key_ref = find_key_to_update(keyring_ref, index_key: &index_key); |
891 | if (key_ref) |
892 | goto found_matching_key; |
893 | } |
894 | } else { |
895 | key_ref = find_key_to_update(keyring_ref, index_key: &index_key); |
896 | if (key_ref) { |
897 | key_ref_put(key_ref); |
898 | key_ref = ERR_PTR(error: -EEXIST); |
899 | goto error_link_end; |
900 | } |
901 | } |
902 | |
903 | /* if the client doesn't provide, decide on the permissions we want */ |
904 | if (perm == KEY_PERM_UNDEF) { |
905 | perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; |
906 | perm |= KEY_USR_VIEW; |
907 | |
908 | if (index_key.type->read) |
909 | perm |= KEY_POS_READ; |
910 | |
911 | if (index_key.type == &key_type_keyring || |
912 | index_key.type->update) |
913 | perm |= KEY_POS_WRITE; |
914 | } |
915 | |
916 | /* allocate a new key */ |
917 | key = key_alloc(index_key.type, index_key.description, |
918 | cred->fsuid, cred->fsgid, cred, perm, flags, NULL); |
919 | if (IS_ERR(ptr: key)) { |
920 | key_ref = ERR_CAST(ptr: key); |
921 | goto error_link_end; |
922 | } |
923 | |
924 | /* instantiate it and link it into the target keyring */ |
925 | ret = __key_instantiate_and_link(key, prep: &prep, keyring, NULL, edit: &edit); |
926 | if (ret < 0) { |
927 | key_put(key); |
928 | key_ref = ERR_PTR(error: ret); |
929 | goto error_link_end; |
930 | } |
931 | |
932 | security_key_post_create_or_update(keyring, key, payload, payload_len: plen, flags, |
933 | create: true); |
934 | |
935 | key_ref = make_key_ref(key, possession: is_key_possessed(key_ref: keyring_ref)); |
936 | |
937 | error_link_end: |
938 | __key_link_end(keyring, index_key: &index_key, edit); |
939 | error_free_prep: |
940 | if (index_key.type->preparse) |
941 | index_key.type->free_preparse(&prep); |
942 | error_put_type: |
943 | key_type_put(ktype: index_key.type); |
944 | error: |
945 | return key_ref; |
946 | |
947 | found_matching_key: |
948 | /* we found a matching key, so we're going to try to update it |
949 | * - we can drop the locks first as we have the key pinned |
950 | */ |
951 | __key_link_end(keyring, index_key: &index_key, edit); |
952 | |
953 | key = key_ref_to_ptr(key_ref); |
954 | if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) { |
955 | ret = wait_for_key_construction(key, intr: true); |
956 | if (ret < 0) { |
957 | key_ref_put(key_ref); |
958 | key_ref = ERR_PTR(error: ret); |
959 | goto error_free_prep; |
960 | } |
961 | } |
962 | |
963 | key_ref = __key_update(key_ref, prep: &prep); |
964 | |
965 | if (!IS_ERR(ptr: key_ref)) |
966 | security_key_post_create_or_update(keyring, key, payload, payload_len: plen, |
967 | flags, create: false); |
968 | |
969 | goto error_free_prep; |
970 | } |
971 | |
972 | /** |
973 | * key_create_or_update - Update or create and instantiate a key. |
974 | * @keyring_ref: A pointer to the destination keyring with possession flag. |
975 | * @type: The type of key. |
976 | * @description: The searchable description for the key. |
977 | * @payload: The data to use to instantiate or update the key. |
978 | * @plen: The length of @payload. |
979 | * @perm: The permissions mask for a new key. |
980 | * @flags: The quota flags for a new key. |
981 | * |
982 | * Search the destination keyring for a key of the same description and if one |
983 | * is found, update it, otherwise create and instantiate a new one and create a |
984 | * link to it from that keyring. |
985 | * |
986 | * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be |
987 | * concocted. |
988 | * |
989 | * Returns a pointer to the new key if successful, -ENODEV if the key type |
990 | * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the |
991 | * caller isn't permitted to modify the keyring or the LSM did not permit |
992 | * creation of the key. |
993 | * |
994 | * On success, the possession flag from the keyring ref will be tacked on to |
995 | * the key ref before it is returned. |
996 | */ |
997 | key_ref_t key_create_or_update(key_ref_t keyring_ref, |
998 | const char *type, |
999 | const char *description, |
1000 | const void *payload, |
1001 | size_t plen, |
1002 | key_perm_t perm, |
1003 | unsigned long flags) |
1004 | { |
1005 | return __key_create_or_update(keyring_ref, type, description, payload, |
1006 | plen, perm, flags, allow_update: true); |
1007 | } |
1008 | EXPORT_SYMBOL(key_create_or_update); |
1009 | |
1010 | /** |
1011 | * key_create - Create and instantiate a key. |
1012 | * @keyring_ref: A pointer to the destination keyring with possession flag. |
1013 | * @type: The type of key. |
1014 | * @description: The searchable description for the key. |
1015 | * @payload: The data to use to instantiate or update the key. |
1016 | * @plen: The length of @payload. |
1017 | * @perm: The permissions mask for a new key. |
1018 | * @flags: The quota flags for a new key. |
1019 | * |
1020 | * Create and instantiate a new key and link to it from the destination keyring. |
1021 | * |
1022 | * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be |
1023 | * concocted. |
1024 | * |
1025 | * Returns a pointer to the new key if successful, -EEXIST if a key with the |
1026 | * same description already exists, -ENODEV if the key type wasn't available, |
1027 | * -ENOTDIR if the keyring wasn't a keyring, -EACCES if the caller isn't |
1028 | * permitted to modify the keyring or the LSM did not permit creation of the |
1029 | * key. |
1030 | * |
1031 | * On success, the possession flag from the keyring ref will be tacked on to |
1032 | * the key ref before it is returned. |
1033 | */ |
1034 | key_ref_t key_create(key_ref_t keyring_ref, |
1035 | const char *type, |
1036 | const char *description, |
1037 | const void *payload, |
1038 | size_t plen, |
1039 | key_perm_t perm, |
1040 | unsigned long flags) |
1041 | { |
1042 | return __key_create_or_update(keyring_ref, type, description, payload, |
1043 | plen, perm, flags, allow_update: false); |
1044 | } |
1045 | EXPORT_SYMBOL(key_create); |
1046 | |
1047 | /** |
1048 | * key_update - Update a key's contents. |
1049 | * @key_ref: The pointer (plus possession flag) to the key. |
1050 | * @payload: The data to be used to update the key. |
1051 | * @plen: The length of @payload. |
1052 | * |
1053 | * Attempt to update the contents of a key with the given payload data. The |
1054 | * caller must be granted Write permission on the key. Negative keys can be |
1055 | * instantiated by this method. |
1056 | * |
1057 | * Returns 0 on success, -EACCES if not permitted and -EOPNOTSUPP if the key |
1058 | * type does not support updating. The key type may return other errors. |
1059 | */ |
1060 | int key_update(key_ref_t key_ref, const void *payload, size_t plen) |
1061 | { |
1062 | struct key_preparsed_payload prep; |
1063 | struct key *key = key_ref_to_ptr(key_ref); |
1064 | int ret; |
1065 | |
1066 | key_check(key); |
1067 | |
1068 | /* the key must be writable */ |
1069 | ret = key_permission(key_ref, need_perm: KEY_NEED_WRITE); |
1070 | if (ret < 0) |
1071 | return ret; |
1072 | |
1073 | /* attempt to update it if supported */ |
1074 | if (!key->type->update) |
1075 | return -EOPNOTSUPP; |
1076 | |
1077 | memset(&prep, 0, sizeof(prep)); |
1078 | prep.data = payload; |
1079 | prep.datalen = plen; |
1080 | prep.quotalen = key->type->def_datalen; |
1081 | prep.expiry = TIME64_MAX; |
1082 | if (key->type->preparse) { |
1083 | ret = key->type->preparse(&prep); |
1084 | if (ret < 0) |
1085 | goto error; |
1086 | } |
1087 | |
1088 | down_write(sem: &key->sem); |
1089 | |
1090 | ret = key->type->update(key, &prep); |
1091 | if (ret == 0) { |
1092 | /* Updating a negative key positively instantiates it */ |
1093 | mark_key_instantiated(key, reject_error: 0); |
1094 | notify_key(key, subtype: NOTIFY_KEY_UPDATED, aux: 0); |
1095 | } |
1096 | |
1097 | up_write(sem: &key->sem); |
1098 | |
1099 | error: |
1100 | if (key->type->preparse) |
1101 | key->type->free_preparse(&prep); |
1102 | return ret; |
1103 | } |
1104 | EXPORT_SYMBOL(key_update); |
1105 | |
1106 | /** |
1107 | * key_revoke - Revoke a key. |
1108 | * @key: The key to be revoked. |
1109 | * |
1110 | * Mark a key as being revoked and ask the type to free up its resources. The |
1111 | * revocation timeout is set and the key and all its links will be |
1112 | * automatically garbage collected after key_gc_delay amount of time if they |
1113 | * are not manually dealt with first. |
1114 | */ |
1115 | void key_revoke(struct key *key) |
1116 | { |
1117 | time64_t time; |
1118 | |
1119 | key_check(key); |
1120 | |
1121 | /* make sure no one's trying to change or use the key when we mark it |
1122 | * - we tell lockdep that we might nest because we might be revoking an |
1123 | * authorisation key whilst holding the sem on a key we've just |
1124 | * instantiated |
1125 | */ |
1126 | down_write_nested(sem: &key->sem, subclass: 1); |
1127 | if (!test_and_set_bit(KEY_FLAG_REVOKED, addr: &key->flags)) { |
1128 | notify_key(key, subtype: NOTIFY_KEY_REVOKED, aux: 0); |
1129 | if (key->type->revoke) |
1130 | key->type->revoke(key); |
1131 | |
1132 | /* set the death time to no more than the expiry time */ |
1133 | time = ktime_get_real_seconds(); |
1134 | if (key->revoked_at == 0 || key->revoked_at > time) { |
1135 | key->revoked_at = time; |
1136 | key_schedule_gc(gc_at: key->revoked_at + key_gc_delay); |
1137 | } |
1138 | } |
1139 | |
1140 | up_write(sem: &key->sem); |
1141 | } |
1142 | EXPORT_SYMBOL(key_revoke); |
1143 | |
1144 | /** |
1145 | * key_invalidate - Invalidate a key. |
1146 | * @key: The key to be invalidated. |
1147 | * |
1148 | * Mark a key as being invalidated and have it cleaned up immediately. The key |
1149 | * is ignored by all searches and other operations from this point. |
1150 | */ |
1151 | void key_invalidate(struct key *key) |
1152 | { |
1153 | kenter("%d" , key_serial(key)); |
1154 | |
1155 | key_check(key); |
1156 | |
1157 | if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) { |
1158 | down_write_nested(sem: &key->sem, subclass: 1); |
1159 | if (!test_and_set_bit(KEY_FLAG_INVALIDATED, addr: &key->flags)) { |
1160 | notify_key(key, subtype: NOTIFY_KEY_INVALIDATED, aux: 0); |
1161 | key_schedule_gc_links(); |
1162 | } |
1163 | up_write(sem: &key->sem); |
1164 | } |
1165 | } |
1166 | EXPORT_SYMBOL(key_invalidate); |
1167 | |
1168 | /** |
1169 | * generic_key_instantiate - Simple instantiation of a key from preparsed data |
1170 | * @key: The key to be instantiated |
1171 | * @prep: The preparsed data to load. |
1172 | * |
1173 | * Instantiate a key from preparsed data. We assume we can just copy the data |
1174 | * in directly and clear the old pointers. |
1175 | * |
1176 | * This can be pointed to directly by the key type instantiate op pointer. |
1177 | */ |
1178 | int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep) |
1179 | { |
1180 | int ret; |
1181 | |
1182 | pr_devel("==>%s()\n" , __func__); |
1183 | |
1184 | ret = key_payload_reserve(key, prep->quotalen); |
1185 | if (ret == 0) { |
1186 | rcu_assign_keypointer(key, prep->payload.data[0]); |
1187 | key->payload.data[1] = prep->payload.data[1]; |
1188 | key->payload.data[2] = prep->payload.data[2]; |
1189 | key->payload.data[3] = prep->payload.data[3]; |
1190 | prep->payload.data[0] = NULL; |
1191 | prep->payload.data[1] = NULL; |
1192 | prep->payload.data[2] = NULL; |
1193 | prep->payload.data[3] = NULL; |
1194 | } |
1195 | pr_devel("<==%s() = %d\n" , __func__, ret); |
1196 | return ret; |
1197 | } |
1198 | EXPORT_SYMBOL(generic_key_instantiate); |
1199 | |
1200 | /** |
1201 | * register_key_type - Register a type of key. |
1202 | * @ktype: The new key type. |
1203 | * |
1204 | * Register a new key type. |
1205 | * |
1206 | * Returns 0 on success or -EEXIST if a type of this name already exists. |
1207 | */ |
1208 | int register_key_type(struct key_type *ktype) |
1209 | { |
1210 | struct key_type *p; |
1211 | int ret; |
1212 | |
1213 | memset(&ktype->lock_class, 0, sizeof(ktype->lock_class)); |
1214 | |
1215 | ret = -EEXIST; |
1216 | down_write(sem: &key_types_sem); |
1217 | |
1218 | /* disallow key types with the same name */ |
1219 | list_for_each_entry(p, &key_types_list, link) { |
1220 | if (strcmp(p->name, ktype->name) == 0) |
1221 | goto out; |
1222 | } |
1223 | |
1224 | /* store the type */ |
1225 | list_add(new: &ktype->link, head: &key_types_list); |
1226 | |
1227 | pr_notice("Key type %s registered\n" , ktype->name); |
1228 | ret = 0; |
1229 | |
1230 | out: |
1231 | up_write(sem: &key_types_sem); |
1232 | return ret; |
1233 | } |
1234 | EXPORT_SYMBOL(register_key_type); |
1235 | |
1236 | /** |
1237 | * unregister_key_type - Unregister a type of key. |
1238 | * @ktype: The key type. |
1239 | * |
1240 | * Unregister a key type and mark all the extant keys of this type as dead. |
1241 | * Those keys of this type are then destroyed to get rid of their payloads and |
1242 | * they and their links will be garbage collected as soon as possible. |
1243 | */ |
1244 | void unregister_key_type(struct key_type *ktype) |
1245 | { |
1246 | down_write(sem: &key_types_sem); |
1247 | list_del_init(entry: &ktype->link); |
1248 | downgrade_write(sem: &key_types_sem); |
1249 | key_gc_keytype(ktype); |
1250 | pr_notice("Key type %s unregistered\n" , ktype->name); |
1251 | up_read(sem: &key_types_sem); |
1252 | } |
1253 | EXPORT_SYMBOL(unregister_key_type); |
1254 | |
1255 | /* |
1256 | * Initialise the key management state. |
1257 | */ |
1258 | void __init key_init(void) |
1259 | { |
1260 | /* allocate a slab in which we can store keys */ |
1261 | key_jar = kmem_cache_create(name: "key_jar" , size: sizeof(struct key), |
1262 | align: 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1263 | |
1264 | /* add the special key types */ |
1265 | list_add_tail(new: &key_type_keyring.link, head: &key_types_list); |
1266 | list_add_tail(new: &key_type_dead.link, head: &key_types_list); |
1267 | list_add_tail(new: &key_type_user.link, head: &key_types_list); |
1268 | list_add_tail(new: &key_type_logon.link, head: &key_types_list); |
1269 | |
1270 | /* record the root user tracking */ |
1271 | rb_link_node(node: &root_key_user.node, |
1272 | NULL, |
1273 | rb_link: &key_user_tree.rb_node); |
1274 | |
1275 | rb_insert_color(&root_key_user.node, |
1276 | &key_user_tree); |
1277 | } |
1278 | |