Root/security/keys/keyctl.c

Source at commit be977234bfb4a6dca8a39e7c52165e4cd536ad71 created 9 years 5 months ago.
By Lars-Peter Clausen, jz4740: Fix compile error
1/* Userspace key control operations
2 *
3 * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/sched.h>
15#include <linux/slab.h>
16#include <linux/syscalls.h>
17#include <linux/keyctl.h>
18#include <linux/fs.h>
19#include <linux/capability.h>
20#include <linux/string.h>
21#include <linux/err.h>
22#include <linux/vmalloc.h>
23#include <linux/security.h>
24#include <asm/uaccess.h>
25#include "internal.h"
26
27static int key_get_type_from_user(char *type,
28                  const char __user *_type,
29                  unsigned len)
30{
31    int ret;
32
33    ret = strncpy_from_user(type, _type, len);
34    if (ret < 0)
35        return ret;
36    if (ret == 0 || ret >= len)
37        return -EINVAL;
38    if (type[0] == '.')
39        return -EPERM;
40    type[len - 1] = '\0';
41    return 0;
42}
43
44/*
45 * Extract the description of a new key from userspace and either add it as a
46 * new key to the specified keyring or update a matching key in that keyring.
47 *
48 * The keyring must be writable so that we can attach the key to it.
49 *
50 * If successful, the new key's serial number is returned, otherwise an error
51 * code is returned.
52 */
53SYSCALL_DEFINE5(add_key, const char __user *, _type,
54        const char __user *, _description,
55        const void __user *, _payload,
56        size_t, plen,
57        key_serial_t, ringid)
58{
59    key_ref_t keyring_ref, key_ref;
60    char type[32], *description;
61    void *payload;
62    long ret;
63    bool vm;
64
65    ret = -EINVAL;
66    if (plen > 1024 * 1024 - 1)
67        goto error;
68
69    /* draw all the data into kernel space */
70    ret = key_get_type_from_user(type, _type, sizeof(type));
71    if (ret < 0)
72        goto error;
73
74    description = strndup_user(_description, PAGE_SIZE);
75    if (IS_ERR(description)) {
76        ret = PTR_ERR(description);
77        goto error;
78    }
79
80    /* pull the payload in if one was supplied */
81    payload = NULL;
82
83    vm = false;
84    if (_payload) {
85        ret = -ENOMEM;
86        payload = kmalloc(plen, GFP_KERNEL);
87        if (!payload) {
88            if (plen <= PAGE_SIZE)
89                goto error2;
90            vm = true;
91            payload = vmalloc(plen);
92            if (!payload)
93                goto error2;
94        }
95
96        ret = -EFAULT;
97        if (copy_from_user(payload, _payload, plen) != 0)
98            goto error3;
99    }
100
101    /* find the target keyring (which must be writable) */
102    keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
103    if (IS_ERR(keyring_ref)) {
104        ret = PTR_ERR(keyring_ref);
105        goto error3;
106    }
107
108    /* create or update the requested key and add it to the target
109     * keyring */
110    key_ref = key_create_or_update(keyring_ref, type, description,
111                       payload, plen, KEY_PERM_UNDEF,
112                       KEY_ALLOC_IN_QUOTA);
113    if (!IS_ERR(key_ref)) {
114        ret = key_ref_to_ptr(key_ref)->serial;
115        key_ref_put(key_ref);
116    }
117    else {
118        ret = PTR_ERR(key_ref);
119    }
120
121    key_ref_put(keyring_ref);
122 error3:
123    if (!vm)
124        kfree(payload);
125    else
126        vfree(payload);
127 error2:
128    kfree(description);
129 error:
130    return ret;
131}
132
133/*
134 * Search the process keyrings and keyring trees linked from those for a
135 * matching key. Keyrings must have appropriate Search permission to be
136 * searched.
137 *
138 * If a key is found, it will be attached to the destination keyring if there's
139 * one specified and the serial number of the key will be returned.
140 *
141 * If no key is found, /sbin/request-key will be invoked if _callout_info is
142 * non-NULL in an attempt to create a key. The _callout_info string will be
143 * passed to /sbin/request-key to aid with completing the request. If the
144 * _callout_info string is "" then it will be changed to "-".
145 */
146SYSCALL_DEFINE4(request_key, const char __user *, _type,
147        const char __user *, _description,
148        const char __user *, _callout_info,
149        key_serial_t, destringid)
150{
151    struct key_type *ktype;
152    struct key *key;
153    key_ref_t dest_ref;
154    size_t callout_len;
155    char type[32], *description, *callout_info;
156    long ret;
157
158    /* pull the type into kernel space */
159    ret = key_get_type_from_user(type, _type, sizeof(type));
160    if (ret < 0)
161        goto error;
162
163    /* pull the description into kernel space */
164    description = strndup_user(_description, PAGE_SIZE);
165    if (IS_ERR(description)) {
166        ret = PTR_ERR(description);
167        goto error;
168    }
169
170    /* pull the callout info into kernel space */
171    callout_info = NULL;
172    callout_len = 0;
173    if (_callout_info) {
174        callout_info = strndup_user(_callout_info, PAGE_SIZE);
175        if (IS_ERR(callout_info)) {
176            ret = PTR_ERR(callout_info);
177            goto error2;
178        }
179        callout_len = strlen(callout_info);
180    }
181
182    /* get the destination keyring if specified */
183    dest_ref = NULL;
184    if (destringid) {
185        dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
186                       KEY_WRITE);
187        if (IS_ERR(dest_ref)) {
188            ret = PTR_ERR(dest_ref);
189            goto error3;
190        }
191    }
192
193    /* find the key type */
194    ktype = key_type_lookup(type);
195    if (IS_ERR(ktype)) {
196        ret = PTR_ERR(ktype);
197        goto error4;
198    }
199
200    /* do the search */
201    key = request_key_and_link(ktype, description, callout_info,
202                   callout_len, NULL, key_ref_to_ptr(dest_ref),
203                   KEY_ALLOC_IN_QUOTA);
204    if (IS_ERR(key)) {
205        ret = PTR_ERR(key);
206        goto error5;
207    }
208
209    ret = key->serial;
210
211     key_put(key);
212error5:
213    key_type_put(ktype);
214error4:
215    key_ref_put(dest_ref);
216error3:
217    kfree(callout_info);
218error2:
219    kfree(description);
220error:
221    return ret;
222}
223
224/*
225 * Get the ID of the specified process keyring.
226 *
227 * The requested keyring must have search permission to be found.
228 *
229 * If successful, the ID of the requested keyring will be returned.
230 */
231long keyctl_get_keyring_ID(key_serial_t id, int create)
232{
233    key_ref_t key_ref;
234    unsigned long lflags;
235    long ret;
236
237    lflags = create ? KEY_LOOKUP_CREATE : 0;
238    key_ref = lookup_user_key(id, lflags, KEY_SEARCH);
239    if (IS_ERR(key_ref)) {
240        ret = PTR_ERR(key_ref);
241        goto error;
242    }
243
244    ret = key_ref_to_ptr(key_ref)->serial;
245    key_ref_put(key_ref);
246error:
247    return ret;
248}
249
250/*
251 * Join a (named) session keyring.
252 *
253 * Create and join an anonymous session keyring or join a named session
254 * keyring, creating it if necessary. A named session keyring must have Search
255 * permission for it to be joined. Session keyrings without this permit will
256 * be skipped over.
257 *
258 * If successful, the ID of the joined session keyring will be returned.
259 */
260long keyctl_join_session_keyring(const char __user *_name)
261{
262    char *name;
263    long ret;
264
265    /* fetch the name from userspace */
266    name = NULL;
267    if (_name) {
268        name = strndup_user(_name, PAGE_SIZE);
269        if (IS_ERR(name)) {
270            ret = PTR_ERR(name);
271            goto error;
272        }
273    }
274
275    /* join the session */
276    ret = join_session_keyring(name);
277    kfree(name);
278
279error:
280    return ret;
281}
282
283/*
284 * Update a key's data payload from the given data.
285 *
286 * The key must grant the caller Write permission and the key type must support
287 * updating for this to work. A negative key can be positively instantiated
288 * with this call.
289 *
290 * If successful, 0 will be returned. If the key type does not support
291 * updating, then -EOPNOTSUPP will be returned.
292 */
293long keyctl_update_key(key_serial_t id,
294               const void __user *_payload,
295               size_t plen)
296{
297    key_ref_t key_ref;
298    void *payload;
299    long ret;
300
301    ret = -EINVAL;
302    if (plen > PAGE_SIZE)
303        goto error;
304
305    /* pull the payload in if one was supplied */
306    payload = NULL;
307    if (_payload) {
308        ret = -ENOMEM;
309        payload = kmalloc(plen, GFP_KERNEL);
310        if (!payload)
311            goto error;
312
313        ret = -EFAULT;
314        if (copy_from_user(payload, _payload, plen) != 0)
315            goto error2;
316    }
317
318    /* find the target key (which must be writable) */
319    key_ref = lookup_user_key(id, 0, KEY_WRITE);
320    if (IS_ERR(key_ref)) {
321        ret = PTR_ERR(key_ref);
322        goto error2;
323    }
324
325    /* update the key */
326    ret = key_update(key_ref, payload, plen);
327
328    key_ref_put(key_ref);
329error2:
330    kfree(payload);
331error:
332    return ret;
333}
334
335/*
336 * Revoke a key.
337 *
338 * The key must be grant the caller Write or Setattr permission for this to
339 * work. The key type should give up its quota claim when revoked. The key
340 * and any links to the key will be automatically garbage collected after a
341 * certain amount of time (/proc/sys/kernel/keys/gc_delay).
342 *
343 * If successful, 0 is returned.
344 */
345long keyctl_revoke_key(key_serial_t id)
346{
347    key_ref_t key_ref;
348    long ret;
349
350    key_ref = lookup_user_key(id, 0, KEY_WRITE);
351    if (IS_ERR(key_ref)) {
352        ret = PTR_ERR(key_ref);
353        if (ret != -EACCES)
354            goto error;
355        key_ref = lookup_user_key(id, 0, KEY_SETATTR);
356        if (IS_ERR(key_ref)) {
357            ret = PTR_ERR(key_ref);
358            goto error;
359        }
360    }
361
362    key_revoke(key_ref_to_ptr(key_ref));
363    ret = 0;
364
365    key_ref_put(key_ref);
366error:
367    return ret;
368}
369
370/*
371 * Clear the specified keyring, creating an empty process keyring if one of the
372 * special keyring IDs is used.
373 *
374 * The keyring must grant the caller Write permission for this to work. If
375 * successful, 0 will be returned.
376 */
377long keyctl_keyring_clear(key_serial_t ringid)
378{
379    key_ref_t keyring_ref;
380    long ret;
381
382    keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
383    if (IS_ERR(keyring_ref)) {
384        ret = PTR_ERR(keyring_ref);
385        goto error;
386    }
387
388    ret = keyring_clear(key_ref_to_ptr(keyring_ref));
389
390    key_ref_put(keyring_ref);
391error:
392    return ret;
393}
394
395/*
396 * Create a link from a keyring to a key if there's no matching key in the
397 * keyring, otherwise replace the link to the matching key with a link to the
398 * new key.
399 *
400 * The key must grant the caller Link permission and the the keyring must grant
401 * the caller Write permission. Furthermore, if an additional link is created,
402 * the keyring's quota will be extended.
403 *
404 * If successful, 0 will be returned.
405 */
406long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
407{
408    key_ref_t keyring_ref, key_ref;
409    long ret;
410
411    keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
412    if (IS_ERR(keyring_ref)) {
413        ret = PTR_ERR(keyring_ref);
414        goto error;
415    }
416
417    key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_LINK);
418    if (IS_ERR(key_ref)) {
419        ret = PTR_ERR(key_ref);
420        goto error2;
421    }
422
423    ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
424
425    key_ref_put(key_ref);
426error2:
427    key_ref_put(keyring_ref);
428error:
429    return ret;
430}
431
432/*
433 * Unlink a key from a keyring.
434 *
435 * The keyring must grant the caller Write permission for this to work; the key
436 * itself need not grant the caller anything. If the last link to a key is
437 * removed then that key will be scheduled for destruction.
438 *
439 * If successful, 0 will be returned.
440 */
441long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
442{
443    key_ref_t keyring_ref, key_ref;
444    long ret;
445
446    keyring_ref = lookup_user_key(ringid, 0, KEY_WRITE);
447    if (IS_ERR(keyring_ref)) {
448        ret = PTR_ERR(keyring_ref);
449        goto error;
450    }
451
452    key_ref = lookup_user_key(id, KEY_LOOKUP_FOR_UNLINK, 0);
453    if (IS_ERR(key_ref)) {
454        ret = PTR_ERR(key_ref);
455        goto error2;
456    }
457
458    ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
459
460    key_ref_put(key_ref);
461error2:
462    key_ref_put(keyring_ref);
463error:
464    return ret;
465}
466
467/*
468 * Return a description of a key to userspace.
469 *
470 * The key must grant the caller View permission for this to work.
471 *
472 * If there's a buffer, we place up to buflen bytes of data into it formatted
473 * in the following way:
474 *
475 * type;uid;gid;perm;description<NUL>
476 *
477 * If successful, we return the amount of description available, irrespective
478 * of how much we may have copied into the buffer.
479 */
480long keyctl_describe_key(key_serial_t keyid,
481             char __user *buffer,
482             size_t buflen)
483{
484    struct key *key, *instkey;
485    key_ref_t key_ref;
486    char *tmpbuf;
487    long ret;
488
489    key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
490    if (IS_ERR(key_ref)) {
491        /* viewing a key under construction is permitted if we have the
492         * authorisation token handy */
493        if (PTR_ERR(key_ref) == -EACCES) {
494            instkey = key_get_instantiation_authkey(keyid);
495            if (!IS_ERR(instkey)) {
496                key_put(instkey);
497                key_ref = lookup_user_key(keyid,
498                              KEY_LOOKUP_PARTIAL,
499                              0);
500                if (!IS_ERR(key_ref))
501                    goto okay;
502            }
503        }
504
505        ret = PTR_ERR(key_ref);
506        goto error;
507    }
508
509okay:
510    /* calculate how much description we're going to return */
511    ret = -ENOMEM;
512    tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
513    if (!tmpbuf)
514        goto error2;
515
516    key = key_ref_to_ptr(key_ref);
517
518    ret = snprintf(tmpbuf, PAGE_SIZE - 1,
519               "%s;%d;%d;%08x;%s",
520               key->type->name,
521               key->uid,
522               key->gid,
523               key->perm,
524               key->description ?: "");
525
526    /* include a NUL char at the end of the data */
527    if (ret > PAGE_SIZE - 1)
528        ret = PAGE_SIZE - 1;
529    tmpbuf[ret] = 0;
530    ret++;
531
532    /* consider returning the data */
533    if (buffer && buflen > 0) {
534        if (buflen > ret)
535            buflen = ret;
536
537        if (copy_to_user(buffer, tmpbuf, buflen) != 0)
538            ret = -EFAULT;
539    }
540
541    kfree(tmpbuf);
542error2:
543    key_ref_put(key_ref);
544error:
545    return ret;
546}
547
548/*
549 * Search the specified keyring and any keyrings it links to for a matching
550 * key. Only keyrings that grant the caller Search permission will be searched
551 * (this includes the starting keyring). Only keys with Search permission can
552 * be found.
553 *
554 * If successful, the found key will be linked to the destination keyring if
555 * supplied and the key has Link permission, and the found key ID will be
556 * returned.
557 */
558long keyctl_keyring_search(key_serial_t ringid,
559               const char __user *_type,
560               const char __user *_description,
561               key_serial_t destringid)
562{
563    struct key_type *ktype;
564    key_ref_t keyring_ref, key_ref, dest_ref;
565    char type[32], *description;
566    long ret;
567
568    /* pull the type and description into kernel space */
569    ret = key_get_type_from_user(type, _type, sizeof(type));
570    if (ret < 0)
571        goto error;
572
573    description = strndup_user(_description, PAGE_SIZE);
574    if (IS_ERR(description)) {
575        ret = PTR_ERR(description);
576        goto error;
577    }
578
579    /* get the keyring at which to begin the search */
580    keyring_ref = lookup_user_key(ringid, 0, KEY_SEARCH);
581    if (IS_ERR(keyring_ref)) {
582        ret = PTR_ERR(keyring_ref);
583        goto error2;
584    }
585
586    /* get the destination keyring if specified */
587    dest_ref = NULL;
588    if (destringid) {
589        dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
590                       KEY_WRITE);
591        if (IS_ERR(dest_ref)) {
592            ret = PTR_ERR(dest_ref);
593            goto error3;
594        }
595    }
596
597    /* find the key type */
598    ktype = key_type_lookup(type);
599    if (IS_ERR(ktype)) {
600        ret = PTR_ERR(ktype);
601        goto error4;
602    }
603
604    /* do the search */
605    key_ref = keyring_search(keyring_ref, ktype, description);
606    if (IS_ERR(key_ref)) {
607        ret = PTR_ERR(key_ref);
608
609        /* treat lack or presence of a negative key the same */
610        if (ret == -EAGAIN)
611            ret = -ENOKEY;
612        goto error5;
613    }
614
615    /* link the resulting key to the destination keyring if we can */
616    if (dest_ref) {
617        ret = key_permission(key_ref, KEY_LINK);
618        if (ret < 0)
619            goto error6;
620
621        ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
622        if (ret < 0)
623            goto error6;
624    }
625
626    ret = key_ref_to_ptr(key_ref)->serial;
627
628error6:
629    key_ref_put(key_ref);
630error5:
631    key_type_put(ktype);
632error4:
633    key_ref_put(dest_ref);
634error3:
635    key_ref_put(keyring_ref);
636error2:
637    kfree(description);
638error:
639    return ret;
640}
641
642/*
643 * Read a key's payload.
644 *
645 * The key must either grant the caller Read permission, or it must grant the
646 * caller Search permission when searched for from the process keyrings.
647 *
648 * If successful, we place up to buflen bytes of data into the buffer, if one
649 * is provided, and return the amount of data that is available in the key,
650 * irrespective of how much we copied into the buffer.
651 */
652long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
653{
654    struct key *key;
655    key_ref_t key_ref;
656    long ret;
657
658    /* find the key first */
659    key_ref = lookup_user_key(keyid, 0, 0);
660    if (IS_ERR(key_ref)) {
661        ret = -ENOKEY;
662        goto error;
663    }
664
665    key = key_ref_to_ptr(key_ref);
666
667    /* see if we can read it directly */
668    ret = key_permission(key_ref, KEY_READ);
669    if (ret == 0)
670        goto can_read_key;
671    if (ret != -EACCES)
672        goto error;
673
674    /* we can't; see if it's searchable from this process's keyrings
675     * - we automatically take account of the fact that it may be
676     * dangling off an instantiation key
677     */
678    if (!is_key_possessed(key_ref)) {
679        ret = -EACCES;
680        goto error2;
681    }
682
683    /* the key is probably readable - now try to read it */
684can_read_key:
685    ret = key_validate(key);
686    if (ret == 0) {
687        ret = -EOPNOTSUPP;
688        if (key->type->read) {
689            /* read the data with the semaphore held (since we
690             * might sleep) */
691            down_read(&key->sem);
692            ret = key->type->read(key, buffer, buflen);
693            up_read(&key->sem);
694        }
695    }
696
697error2:
698    key_put(key);
699error:
700    return ret;
701}
702
703/*
704 * Change the ownership of a key
705 *
706 * The key must grant the caller Setattr permission for this to work, though
707 * the key need not be fully instantiated yet. For the UID to be changed, or
708 * for the GID to be changed to a group the caller is not a member of, the
709 * caller must have sysadmin capability. If either uid or gid is -1 then that
710 * attribute is not changed.
711 *
712 * If the UID is to be changed, the new user must have sufficient quota to
713 * accept the key. The quota deduction will be removed from the old user to
714 * the new user should the attribute be changed.
715 *
716 * If successful, 0 will be returned.
717 */
718long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
719{
720    struct key_user *newowner, *zapowner = NULL;
721    struct key *key;
722    key_ref_t key_ref;
723    long ret;
724
725    ret = 0;
726    if (uid == (uid_t) -1 && gid == (gid_t) -1)
727        goto error;
728
729    key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
730                  KEY_SETATTR);
731    if (IS_ERR(key_ref)) {
732        ret = PTR_ERR(key_ref);
733        goto error;
734    }
735
736    key = key_ref_to_ptr(key_ref);
737
738    /* make the changes with the locks held to prevent chown/chown races */
739    ret = -EACCES;
740    down_write(&key->sem);
741
742    if (!capable(CAP_SYS_ADMIN)) {
743        /* only the sysadmin can chown a key to some other UID */
744        if (uid != (uid_t) -1 && key->uid != uid)
745            goto error_put;
746
747        /* only the sysadmin can set the key's GID to a group other
748         * than one of those that the current process subscribes to */
749        if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid))
750            goto error_put;
751    }
752
753    /* change the UID */
754    if (uid != (uid_t) -1 && uid != key->uid) {
755        ret = -ENOMEM;
756        newowner = key_user_lookup(uid, current_user_ns());
757        if (!newowner)
758            goto error_put;
759
760        /* transfer the quota burden to the new user */
761        if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
762            unsigned maxkeys = (uid == 0) ?
763                key_quota_root_maxkeys : key_quota_maxkeys;
764            unsigned maxbytes = (uid == 0) ?
765                key_quota_root_maxbytes : key_quota_maxbytes;
766
767            spin_lock(&newowner->lock);
768            if (newowner->qnkeys + 1 >= maxkeys ||
769                newowner->qnbytes + key->quotalen >= maxbytes ||
770                newowner->qnbytes + key->quotalen <
771                newowner->qnbytes)
772                goto quota_overrun;
773
774            newowner->qnkeys++;
775            newowner->qnbytes += key->quotalen;
776            spin_unlock(&newowner->lock);
777
778            spin_lock(&key->user->lock);
779            key->user->qnkeys--;
780            key->user->qnbytes -= key->quotalen;
781            spin_unlock(&key->user->lock);
782        }
783
784        atomic_dec(&key->user->nkeys);
785        atomic_inc(&newowner->nkeys);
786
787        if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
788            atomic_dec(&key->user->nikeys);
789            atomic_inc(&newowner->nikeys);
790        }
791
792        zapowner = key->user;
793        key->user = newowner;
794        key->uid = uid;
795    }
796
797    /* change the GID */
798    if (gid != (gid_t) -1)
799        key->gid = gid;
800
801    ret = 0;
802
803error_put:
804    up_write(&key->sem);
805    key_put(key);
806    if (zapowner)
807        key_user_put(zapowner);
808error:
809    return ret;
810
811quota_overrun:
812    spin_unlock(&newowner->lock);
813    zapowner = newowner;
814    ret = -EDQUOT;
815    goto error_put;
816}
817
818/*
819 * Change the permission mask on a key.
820 *
821 * The key must grant the caller Setattr permission for this to work, though
822 * the key need not be fully instantiated yet. If the caller does not have
823 * sysadmin capability, it may only change the permission on keys that it owns.
824 */
825long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
826{
827    struct key *key;
828    key_ref_t key_ref;
829    long ret;
830
831    ret = -EINVAL;
832    if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
833        goto error;
834
835    key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
836                  KEY_SETATTR);
837    if (IS_ERR(key_ref)) {
838        ret = PTR_ERR(key_ref);
839        goto error;
840    }
841
842    key = key_ref_to_ptr(key_ref);
843
844    /* make the changes with the locks held to prevent chown/chmod races */
845    ret = -EACCES;
846    down_write(&key->sem);
847
848    /* if we're not the sysadmin, we can only change a key that we own */
849    if (capable(CAP_SYS_ADMIN) || key->uid == current_fsuid()) {
850        key->perm = perm;
851        ret = 0;
852    }
853
854    up_write(&key->sem);
855    key_put(key);
856error:
857    return ret;
858}
859
860/*
861 * Get the destination keyring for instantiation and check that the caller has
862 * Write permission on it.
863 */
864static long get_instantiation_keyring(key_serial_t ringid,
865                      struct request_key_auth *rka,
866                      struct key **_dest_keyring)
867{
868    key_ref_t dkref;
869
870    *_dest_keyring = NULL;
871
872    /* just return a NULL pointer if we weren't asked to make a link */
873    if (ringid == 0)
874        return 0;
875
876    /* if a specific keyring is nominated by ID, then use that */
877    if (ringid > 0) {
878        dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
879        if (IS_ERR(dkref))
880            return PTR_ERR(dkref);
881        *_dest_keyring = key_ref_to_ptr(dkref);
882        return 0;
883    }
884
885    if (ringid == KEY_SPEC_REQKEY_AUTH_KEY)
886        return -EINVAL;
887
888    /* otherwise specify the destination keyring recorded in the
889     * authorisation key (any KEY_SPEC_*_KEYRING) */
890    if (ringid >= KEY_SPEC_REQUESTOR_KEYRING) {
891        *_dest_keyring = key_get(rka->dest_keyring);
892        return 0;
893    }
894
895    return -ENOKEY;
896}
897
898/*
899 * Change the request_key authorisation key on the current process.
900 */
901static int keyctl_change_reqkey_auth(struct key *key)
902{
903    struct cred *new;
904
905    new = prepare_creds();
906    if (!new)
907        return -ENOMEM;
908
909    key_put(new->request_key_auth);
910    new->request_key_auth = key_get(key);
911
912    return commit_creds(new);
913}
914
915/*
916 * Copy the iovec data from userspace
917 */
918static long copy_from_user_iovec(void *buffer, const struct iovec *iov,
919                 unsigned ioc)
920{
921    for (; ioc > 0; ioc--) {
922        if (copy_from_user(buffer, iov->iov_base, iov->iov_len) != 0)
923            return -EFAULT;
924        buffer += iov->iov_len;
925        iov++;
926    }
927    return 0;
928}
929
930/*
931 * Instantiate a key with the specified payload and link the key into the
932 * destination keyring if one is given.
933 *
934 * The caller must have the appropriate instantiation permit set for this to
935 * work (see keyctl_assume_authority). No other permissions are required.
936 *
937 * If successful, 0 will be returned.
938 */
939long keyctl_instantiate_key_common(key_serial_t id,
940                   const struct iovec *payload_iov,
941                   unsigned ioc,
942                   size_t plen,
943                   key_serial_t ringid)
944{
945    const struct cred *cred = current_cred();
946    struct request_key_auth *rka;
947    struct key *instkey, *dest_keyring;
948    void *payload;
949    long ret;
950    bool vm = false;
951
952    kenter("%d,,%zu,%d", id, plen, ringid);
953
954    ret = -EINVAL;
955    if (plen > 1024 * 1024 - 1)
956        goto error;
957
958    /* the appropriate instantiation authorisation key must have been
959     * assumed before calling this */
960    ret = -EPERM;
961    instkey = cred->request_key_auth;
962    if (!instkey)
963        goto error;
964
965    rka = instkey->payload.data;
966    if (rka->target_key->serial != id)
967        goto error;
968
969    /* pull the payload in if one was supplied */
970    payload = NULL;
971
972    if (payload_iov) {
973        ret = -ENOMEM;
974        payload = kmalloc(plen, GFP_KERNEL);
975        if (!payload) {
976            if (plen <= PAGE_SIZE)
977                goto error;
978            vm = true;
979            payload = vmalloc(plen);
980            if (!payload)
981                goto error;
982        }
983
984        ret = copy_from_user_iovec(payload, payload_iov, ioc);
985        if (ret < 0)
986            goto error2;
987    }
988
989    /* find the destination keyring amongst those belonging to the
990     * requesting task */
991    ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
992    if (ret < 0)
993        goto error2;
994
995    /* instantiate the key and link it into a keyring */
996    ret = key_instantiate_and_link(rka->target_key, payload, plen,
997                       dest_keyring, instkey);
998
999    key_put(dest_keyring);
1000
1001    /* discard the assumed authority if it's just been disabled by
1002     * instantiation of the key */
1003    if (ret == 0)
1004        keyctl_change_reqkey_auth(NULL);
1005
1006error2:
1007    if (!vm)
1008        kfree(payload);
1009    else
1010        vfree(payload);
1011error:
1012    return ret;
1013}
1014
1015/*
1016 * Instantiate a key with the specified payload and link the key into the
1017 * destination keyring if one is given.
1018 *
1019 * The caller must have the appropriate instantiation permit set for this to
1020 * work (see keyctl_assume_authority). No other permissions are required.
1021 *
1022 * If successful, 0 will be returned.
1023 */
1024long keyctl_instantiate_key(key_serial_t id,
1025                const void __user *_payload,
1026                size_t plen,
1027                key_serial_t ringid)
1028{
1029    if (_payload && plen) {
1030        struct iovec iov[1] = {
1031            [0].iov_base = (void __user *)_payload,
1032            [0].iov_len = plen
1033        };
1034
1035        return keyctl_instantiate_key_common(id, iov, 1, plen, ringid);
1036    }
1037
1038    return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
1039}
1040
1041/*
1042 * Instantiate a key with the specified multipart payload and link the key into
1043 * the destination keyring if one is given.
1044 *
1045 * The caller must have the appropriate instantiation permit set for this to
1046 * work (see keyctl_assume_authority). No other permissions are required.
1047 *
1048 * If successful, 0 will be returned.
1049 */
1050long keyctl_instantiate_key_iov(key_serial_t id,
1051                const struct iovec __user *_payload_iov,
1052                unsigned ioc,
1053                key_serial_t ringid)
1054{
1055    struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
1056    long ret;
1057
1058    if (_payload_iov == 0 || ioc == 0)
1059        goto no_payload;
1060
1061    ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc,
1062                    ARRAY_SIZE(iovstack), iovstack, &iov);
1063    if (ret < 0)
1064        return ret;
1065    if (ret == 0)
1066        goto no_payload_free;
1067
1068    ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid);
1069
1070    if (iov != iovstack)
1071        kfree(iov);
1072    return ret;
1073
1074no_payload_free:
1075    if (iov != iovstack)
1076        kfree(iov);
1077no_payload:
1078    return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
1079}
1080
1081/*
1082 * Negatively instantiate the key with the given timeout (in seconds) and link
1083 * the key into the destination keyring if one is given.
1084 *
1085 * The caller must have the appropriate instantiation permit set for this to
1086 * work (see keyctl_assume_authority). No other permissions are required.
1087 *
1088 * The key and any links to the key will be automatically garbage collected
1089 * after the timeout expires.
1090 *
1091 * Negative keys are used to rate limit repeated request_key() calls by causing
1092 * them to return -ENOKEY until the negative key expires.
1093 *
1094 * If successful, 0 will be returned.
1095 */
1096long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
1097{
1098    return keyctl_reject_key(id, timeout, ENOKEY, ringid);
1099}
1100
1101/*
1102 * Negatively instantiate the key with the given timeout (in seconds) and error
1103 * code and link the key into the destination keyring if one is given.
1104 *
1105 * The caller must have the appropriate instantiation permit set for this to
1106 * work (see keyctl_assume_authority). No other permissions are required.
1107 *
1108 * The key and any links to the key will be automatically garbage collected
1109 * after the timeout expires.
1110 *
1111 * Negative keys are used to rate limit repeated request_key() calls by causing
1112 * them to return the specified error code until the negative key expires.
1113 *
1114 * If successful, 0 will be returned.
1115 */
1116long keyctl_reject_key(key_serial_t id, unsigned timeout, unsigned error,
1117               key_serial_t ringid)
1118{
1119    const struct cred *cred = current_cred();
1120    struct request_key_auth *rka;
1121    struct key *instkey, *dest_keyring;
1122    long ret;
1123
1124    kenter("%d,%u,%u,%d", id, timeout, error, ringid);
1125
1126    /* must be a valid error code and mustn't be a kernel special */
1127    if (error <= 0 ||
1128        error >= MAX_ERRNO ||
1129        error == ERESTARTSYS ||
1130        error == ERESTARTNOINTR ||
1131        error == ERESTARTNOHAND ||
1132        error == ERESTART_RESTARTBLOCK)
1133        return -EINVAL;
1134
1135    /* the appropriate instantiation authorisation key must have been
1136     * assumed before calling this */
1137    ret = -EPERM;
1138    instkey = cred->request_key_auth;
1139    if (!instkey)
1140        goto error;
1141
1142    rka = instkey->payload.data;
1143    if (rka->target_key->serial != id)
1144        goto error;
1145
1146    /* find the destination keyring if present (which must also be
1147     * writable) */
1148    ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
1149    if (ret < 0)
1150        goto error;
1151
1152    /* instantiate the key and link it into a keyring */
1153    ret = key_reject_and_link(rka->target_key, timeout, error,
1154                  dest_keyring, instkey);
1155
1156    key_put(dest_keyring);
1157
1158    /* discard the assumed authority if it's just been disabled by
1159     * instantiation of the key */
1160    if (ret == 0)
1161        keyctl_change_reqkey_auth(NULL);
1162
1163error:
1164    return ret;
1165}
1166
1167/*
1168 * Read or set the default keyring in which request_key() will cache keys and
1169 * return the old setting.
1170 *
1171 * If a process keyring is specified then this will be created if it doesn't
1172 * yet exist. The old setting will be returned if successful.
1173 */
1174long keyctl_set_reqkey_keyring(int reqkey_defl)
1175{
1176    struct cred *new;
1177    int ret, old_setting;
1178
1179    old_setting = current_cred_xxx(jit_keyring);
1180
1181    if (reqkey_defl == KEY_REQKEY_DEFL_NO_CHANGE)
1182        return old_setting;
1183
1184    new = prepare_creds();
1185    if (!new)
1186        return -ENOMEM;
1187
1188    switch (reqkey_defl) {
1189    case KEY_REQKEY_DEFL_THREAD_KEYRING:
1190        ret = install_thread_keyring_to_cred(new);
1191        if (ret < 0)
1192            goto error;
1193        goto set;
1194
1195    case KEY_REQKEY_DEFL_PROCESS_KEYRING:
1196        ret = install_process_keyring_to_cred(new);
1197        if (ret < 0) {
1198            if (ret != -EEXIST)
1199                goto error;
1200            ret = 0;
1201        }
1202        goto set;
1203
1204    case KEY_REQKEY_DEFL_DEFAULT:
1205    case KEY_REQKEY_DEFL_SESSION_KEYRING:
1206    case KEY_REQKEY_DEFL_USER_KEYRING:
1207    case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
1208    case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
1209        goto set;
1210
1211    case KEY_REQKEY_DEFL_NO_CHANGE:
1212    case KEY_REQKEY_DEFL_GROUP_KEYRING:
1213    default:
1214        ret = -EINVAL;
1215        goto error;
1216    }
1217
1218set:
1219    new->jit_keyring = reqkey_defl;
1220    commit_creds(new);
1221    return old_setting;
1222error:
1223    abort_creds(new);
1224    return ret;
1225}
1226
1227/*
1228 * Set or clear the timeout on a key.
1229 *
1230 * Either the key must grant the caller Setattr permission or else the caller
1231 * must hold an instantiation authorisation token for the key.
1232 *
1233 * The timeout is either 0 to clear the timeout, or a number of seconds from
1234 * the current time. The key and any links to the key will be automatically
1235 * garbage collected after the timeout expires.
1236 *
1237 * If successful, 0 is returned.
1238 */
1239long keyctl_set_timeout(key_serial_t id, unsigned timeout)
1240{
1241    struct timespec now;
1242    struct key *key, *instkey;
1243    key_ref_t key_ref;
1244    time_t expiry;
1245    long ret;
1246
1247    key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
1248                  KEY_SETATTR);
1249    if (IS_ERR(key_ref)) {
1250        /* setting the timeout on a key under construction is permitted
1251         * if we have the authorisation token handy */
1252        if (PTR_ERR(key_ref) == -EACCES) {
1253            instkey = key_get_instantiation_authkey(id);
1254            if (!IS_ERR(instkey)) {
1255                key_put(instkey);
1256                key_ref = lookup_user_key(id,
1257                              KEY_LOOKUP_PARTIAL,
1258                              0);
1259                if (!IS_ERR(key_ref))
1260                    goto okay;
1261            }
1262        }
1263
1264        ret = PTR_ERR(key_ref);
1265        goto error;
1266    }
1267
1268okay:
1269    key = key_ref_to_ptr(key_ref);
1270
1271    /* make the changes with the locks held to prevent races */
1272    down_write(&key->sem);
1273
1274    expiry = 0;
1275    if (timeout > 0) {
1276        now = current_kernel_time();
1277        expiry = now.tv_sec + timeout;
1278    }
1279
1280    key->expiry = expiry;
1281    key_schedule_gc(key->expiry + key_gc_delay);
1282
1283    up_write(&key->sem);
1284    key_put(key);
1285
1286    ret = 0;
1287error:
1288    return ret;
1289}
1290
1291/*
1292 * Assume (or clear) the authority to instantiate the specified key.
1293 *
1294 * This sets the authoritative token currently in force for key instantiation.
1295 * This must be done for a key to be instantiated. It has the effect of making
1296 * available all the keys from the caller of the request_key() that created a
1297 * key to request_key() calls made by the caller of this function.
1298 *
1299 * The caller must have the instantiation key in their process keyrings with a
1300 * Search permission grant available to the caller.
1301 *
1302 * If the ID given is 0, then the setting will be cleared and 0 returned.
1303 *
1304 * If the ID given has a matching an authorisation key, then that key will be
1305 * set and its ID will be returned. The authorisation key can be read to get
1306 * the callout information passed to request_key().
1307 */
1308long keyctl_assume_authority(key_serial_t id)
1309{
1310    struct key *authkey;
1311    long ret;
1312
1313    /* special key IDs aren't permitted */
1314    ret = -EINVAL;
1315    if (id < 0)
1316        goto error;
1317
1318    /* we divest ourselves of authority if given an ID of 0 */
1319    if (id == 0) {
1320        ret = keyctl_change_reqkey_auth(NULL);
1321        goto error;
1322    }
1323
1324    /* attempt to assume the authority temporarily granted to us whilst we
1325     * instantiate the specified key
1326     * - the authorisation key must be in the current task's keyrings
1327     * somewhere
1328     */
1329    authkey = key_get_instantiation_authkey(id);
1330    if (IS_ERR(authkey)) {
1331        ret = PTR_ERR(authkey);
1332        goto error;
1333    }
1334
1335    ret = keyctl_change_reqkey_auth(authkey);
1336    if (ret < 0)
1337        goto error;
1338    key_put(authkey);
1339
1340    ret = authkey->serial;
1341error:
1342    return ret;
1343}
1344
1345/*
1346 * Get a key's the LSM security label.
1347 *
1348 * The key must grant the caller View permission for this to work.
1349 *
1350 * If there's a buffer, then up to buflen bytes of data will be placed into it.
1351 *
1352 * If successful, the amount of information available will be returned,
1353 * irrespective of how much was copied (including the terminal NUL).
1354 */
1355long keyctl_get_security(key_serial_t keyid,
1356             char __user *buffer,
1357             size_t buflen)
1358{
1359    struct key *key, *instkey;
1360    key_ref_t key_ref;
1361    char *context;
1362    long ret;
1363
1364    key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
1365    if (IS_ERR(key_ref)) {
1366        if (PTR_ERR(key_ref) != -EACCES)
1367            return PTR_ERR(key_ref);
1368
1369        /* viewing a key under construction is also permitted if we
1370         * have the authorisation token handy */
1371        instkey = key_get_instantiation_authkey(keyid);
1372        if (IS_ERR(instkey))
1373            return PTR_ERR(instkey);
1374        key_put(instkey);
1375
1376        key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, 0);
1377        if (IS_ERR(key_ref))
1378            return PTR_ERR(key_ref);
1379    }
1380
1381    key = key_ref_to_ptr(key_ref);
1382    ret = security_key_getsecurity(key, &context);
1383    if (ret == 0) {
1384        /* if no information was returned, give userspace an empty
1385         * string */
1386        ret = 1;
1387        if (buffer && buflen > 0 &&
1388            copy_to_user(buffer, "", 1) != 0)
1389            ret = -EFAULT;
1390    } else if (ret > 0) {
1391        /* return as much data as there's room for */
1392        if (buffer && buflen > 0) {
1393            if (buflen > ret)
1394                buflen = ret;
1395
1396            if (copy_to_user(buffer, context, buflen) != 0)
1397                ret = -EFAULT;
1398        }
1399
1400        kfree(context);
1401    }
1402
1403    key_ref_put(key_ref);
1404    return ret;
1405}
1406
1407/*
1408 * Attempt to install the calling process's session keyring on the process's
1409 * parent process.
1410 *
1411 * The keyring must exist and must grant the caller LINK permission, and the
1412 * parent process must be single-threaded and must have the same effective
1413 * ownership as this process and mustn't be SUID/SGID.
1414 *
1415 * The keyring will be emplaced on the parent when it next resumes userspace.
1416 *
1417 * If successful, 0 will be returned.
1418 */
1419long keyctl_session_to_parent(void)
1420{
1421#ifdef TIF_NOTIFY_RESUME
1422    struct task_struct *me, *parent;
1423    const struct cred *mycred, *pcred;
1424    struct cred *cred, *oldcred;
1425    key_ref_t keyring_r;
1426    int ret;
1427
1428    keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_LINK);
1429    if (IS_ERR(keyring_r))
1430        return PTR_ERR(keyring_r);
1431
1432    /* our parent is going to need a new cred struct, a new tgcred struct
1433     * and new security data, so we allocate them here to prevent ENOMEM in
1434     * our parent */
1435    ret = -ENOMEM;
1436    cred = cred_alloc_blank();
1437    if (!cred)
1438        goto error_keyring;
1439
1440    cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r);
1441    keyring_r = NULL;
1442
1443    me = current;
1444    rcu_read_lock();
1445    write_lock_irq(&tasklist_lock);
1446
1447    parent = me->real_parent;
1448    ret = -EPERM;
1449
1450    /* the parent mustn't be init and mustn't be a kernel thread */
1451    if (parent->pid <= 1 || !parent->mm)
1452        goto not_permitted;
1453
1454    /* the parent must be single threaded */
1455    if (!thread_group_empty(parent))
1456        goto not_permitted;
1457
1458    /* the parent and the child must have different session keyrings or
1459     * there's no point */
1460    mycred = current_cred();
1461    pcred = __task_cred(parent);
1462    if (mycred == pcred ||
1463        mycred->tgcred->session_keyring == pcred->tgcred->session_keyring)
1464        goto already_same;
1465
1466    /* the parent must have the same effective ownership and mustn't be
1467     * SUID/SGID */
1468    if (pcred->uid != mycred->euid ||
1469        pcred->euid != mycred->euid ||
1470        pcred->suid != mycred->euid ||
1471        pcred->gid != mycred->egid ||
1472        pcred->egid != mycred->egid ||
1473        pcred->sgid != mycred->egid)
1474        goto not_permitted;
1475
1476    /* the keyrings must have the same UID */
1477    if ((pcred->tgcred->session_keyring &&
1478         pcred->tgcred->session_keyring->uid != mycred->euid) ||
1479        mycred->tgcred->session_keyring->uid != mycred->euid)
1480        goto not_permitted;
1481
1482    /* if there's an already pending keyring replacement, then we replace
1483     * that */
1484    oldcred = parent->replacement_session_keyring;
1485
1486    /* the replacement session keyring is applied just prior to userspace
1487     * restarting */
1488    parent->replacement_session_keyring = cred;
1489    cred = NULL;
1490    set_ti_thread_flag(task_thread_info(parent), TIF_NOTIFY_RESUME);
1491
1492    write_unlock_irq(&tasklist_lock);
1493    rcu_read_unlock();
1494    if (oldcred)
1495        put_cred(oldcred);
1496    return 0;
1497
1498already_same:
1499    ret = 0;
1500not_permitted:
1501    write_unlock_irq(&tasklist_lock);
1502    rcu_read_unlock();
1503    put_cred(cred);
1504    return ret;
1505
1506error_keyring:
1507    key_ref_put(keyring_r);
1508    return ret;
1509
1510#else /* !TIF_NOTIFY_RESUME */
1511    /*
1512     * To be removed when TIF_NOTIFY_RESUME has been implemented on
1513     * m68k/xtensa
1514     */
1515#warning TIF_NOTIFY_RESUME not implemented
1516    return -EOPNOTSUPP;
1517#endif /* !TIF_NOTIFY_RESUME */
1518}
1519
1520/*
1521 * The key control system call
1522 */
1523SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
1524        unsigned long, arg4, unsigned long, arg5)
1525{
1526    switch (option) {
1527    case KEYCTL_GET_KEYRING_ID:
1528        return keyctl_get_keyring_ID((key_serial_t) arg2,
1529                         (int) arg3);
1530
1531    case KEYCTL_JOIN_SESSION_KEYRING:
1532        return keyctl_join_session_keyring((const char __user *) arg2);
1533
1534    case KEYCTL_UPDATE:
1535        return keyctl_update_key((key_serial_t) arg2,
1536                     (const void __user *) arg3,
1537                     (size_t) arg4);
1538
1539    case KEYCTL_REVOKE:
1540        return keyctl_revoke_key((key_serial_t) arg2);
1541
1542    case KEYCTL_DESCRIBE:
1543        return keyctl_describe_key((key_serial_t) arg2,
1544                       (char __user *) arg3,
1545                       (unsigned) arg4);
1546
1547    case KEYCTL_CLEAR:
1548        return keyctl_keyring_clear((key_serial_t) arg2);
1549
1550    case KEYCTL_LINK:
1551        return keyctl_keyring_link((key_serial_t) arg2,
1552                       (key_serial_t) arg3);
1553
1554    case KEYCTL_UNLINK:
1555        return keyctl_keyring_unlink((key_serial_t) arg2,
1556                         (key_serial_t) arg3);
1557
1558    case KEYCTL_SEARCH:
1559        return keyctl_keyring_search((key_serial_t) arg2,
1560                         (const char __user *) arg3,
1561                         (const char __user *) arg4,
1562                         (key_serial_t) arg5);
1563
1564    case KEYCTL_READ:
1565        return keyctl_read_key((key_serial_t) arg2,
1566                       (char __user *) arg3,
1567                       (size_t) arg4);
1568
1569    case KEYCTL_CHOWN:
1570        return keyctl_chown_key((key_serial_t) arg2,
1571                    (uid_t) arg3,
1572                    (gid_t) arg4);
1573
1574    case KEYCTL_SETPERM:
1575        return keyctl_setperm_key((key_serial_t) arg2,
1576                      (key_perm_t) arg3);
1577
1578    case KEYCTL_INSTANTIATE:
1579        return keyctl_instantiate_key((key_serial_t) arg2,
1580                          (const void __user *) arg3,
1581                          (size_t) arg4,
1582                          (key_serial_t) arg5);
1583
1584    case KEYCTL_NEGATE:
1585        return keyctl_negate_key((key_serial_t) arg2,
1586                     (unsigned) arg3,
1587                     (key_serial_t) arg4);
1588
1589    case KEYCTL_SET_REQKEY_KEYRING:
1590        return keyctl_set_reqkey_keyring(arg2);
1591
1592    case KEYCTL_SET_TIMEOUT:
1593        return keyctl_set_timeout((key_serial_t) arg2,
1594                      (unsigned) arg3);
1595
1596    case KEYCTL_ASSUME_AUTHORITY:
1597        return keyctl_assume_authority((key_serial_t) arg2);
1598
1599    case KEYCTL_GET_SECURITY:
1600        return keyctl_get_security((key_serial_t) arg2,
1601                       (char __user *) arg3,
1602                       (size_t) arg4);
1603
1604    case KEYCTL_SESSION_TO_PARENT:
1605        return keyctl_session_to_parent();
1606
1607    case KEYCTL_REJECT:
1608        return keyctl_reject_key((key_serial_t) arg2,
1609                     (unsigned) arg3,
1610                     (unsigned) arg4,
1611                     (key_serial_t) arg5);
1612
1613    case KEYCTL_INSTANTIATE_IOV:
1614        return keyctl_instantiate_key_iov(
1615            (key_serial_t) arg2,
1616            (const struct iovec __user *) arg3,
1617            (unsigned) arg4,
1618            (key_serial_t) arg5);
1619
1620    default:
1621        return -EOPNOTSUPP;
1622    }
1623}
1624

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