1 /* keyctl.c: userspace keyctl operations
3 * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
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>
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>
27 static int key_get_type_from_user(char *type
,
28 const char __user
*_type
,
33 ret
= strncpy_from_user(type
, _type
, len
);
38 if (ret
== 0 || ret
>= len
)
49 /*****************************************************************************/
51 * extract the description of a new key from userspace and either add it as a
52 * new key to the specified keyring or update a matching key in that keyring
53 * - the keyring must be writable
54 * - returns the new key's serial number
55 * - implements add_key()
57 SYSCALL_DEFINE5(add_key
, const char __user
*, _type
,
58 const char __user
*, _description
,
59 const void __user
*, _payload
,
63 key_ref_t keyring_ref
, key_ref
;
64 char type
[32], *description
;
70 if (plen
> 1024 * 1024 - 1)
73 /* draw all the data into kernel space */
74 ret
= key_get_type_from_user(type
, _type
, sizeof(type
));
78 description
= strndup_user(_description
, PAGE_SIZE
);
79 if (IS_ERR(description
)) {
80 ret
= PTR_ERR(description
);
84 /* pull the payload in if one was supplied */
90 payload
= kmalloc(plen
, GFP_KERNEL
);
92 if (plen
<= PAGE_SIZE
)
95 payload
= vmalloc(plen
);
101 if (copy_from_user(payload
, _payload
, plen
) != 0)
105 /* find the target keyring (which must be writable) */
106 keyring_ref
= lookup_user_key(NULL
, ringid
, 1, 0, KEY_WRITE
);
107 if (IS_ERR(keyring_ref
)) {
108 ret
= PTR_ERR(keyring_ref
);
112 /* create or update the requested key and add it to the target
114 key_ref
= key_create_or_update(keyring_ref
, type
, description
,
115 payload
, plen
, KEY_PERM_UNDEF
,
117 if (!IS_ERR(key_ref
)) {
118 ret
= key_ref_to_ptr(key_ref
)->serial
;
119 key_ref_put(key_ref
);
122 ret
= PTR_ERR(key_ref
);
125 key_ref_put(keyring_ref
);
136 } /* end sys_add_key() */
138 /*****************************************************************************/
140 * search the process keyrings for a matching key
141 * - nested keyrings may also be searched if they have Search permission
142 * - if a key is found, it will be attached to the destination keyring if
143 * there's one specified
144 * - /sbin/request-key will be invoked if _callout_info is non-NULL
145 * - the _callout_info string will be passed to /sbin/request-key
146 * - if the _callout_info string is empty, it will be rendered as "-"
147 * - implements request_key()
149 SYSCALL_DEFINE4(request_key
, const char __user
*, _type
,
150 const char __user
*, _description
,
151 const char __user
*, _callout_info
,
152 key_serial_t
, destringid
)
154 struct key_type
*ktype
;
158 char type
[32], *description
, *callout_info
;
161 /* pull the type into kernel space */
162 ret
= key_get_type_from_user(type
, _type
, sizeof(type
));
166 /* pull the description into kernel space */
167 description
= strndup_user(_description
, PAGE_SIZE
);
168 if (IS_ERR(description
)) {
169 ret
= PTR_ERR(description
);
173 /* pull the callout info into kernel space */
177 callout_info
= strndup_user(_callout_info
, PAGE_SIZE
);
178 if (IS_ERR(callout_info
)) {
179 ret
= PTR_ERR(callout_info
);
182 callout_len
= strlen(callout_info
);
185 /* get the destination keyring if specified */
188 dest_ref
= lookup_user_key(NULL
, destringid
, 1, 0, KEY_WRITE
);
189 if (IS_ERR(dest_ref
)) {
190 ret
= PTR_ERR(dest_ref
);
195 /* find the key type */
196 ktype
= key_type_lookup(type
);
198 ret
= PTR_ERR(ktype
);
203 key
= request_key_and_link(ktype
, description
, callout_info
,
204 callout_len
, NULL
, key_ref_to_ptr(dest_ref
),
217 key_ref_put(dest_ref
);
225 } /* end sys_request_key() */
227 /*****************************************************************************/
229 * get the ID of the specified process keyring
230 * - the keyring must have search permission to be found
231 * - implements keyctl(KEYCTL_GET_KEYRING_ID)
233 long keyctl_get_keyring_ID(key_serial_t id
, int create
)
238 key_ref
= lookup_user_key(NULL
, id
, create
, 0, KEY_SEARCH
);
239 if (IS_ERR(key_ref
)) {
240 ret
= PTR_ERR(key_ref
);
244 ret
= key_ref_to_ptr(key_ref
)->serial
;
245 key_ref_put(key_ref
);
249 } /* end keyctl_get_keyring_ID() */
251 /*****************************************************************************/
253 * join the session keyring
254 * - implements keyctl(KEYCTL_JOIN_SESSION_KEYRING)
256 long keyctl_join_session_keyring(const char __user
*_name
)
261 /* fetch the name from userspace */
264 name
= strndup_user(_name
, PAGE_SIZE
);
271 /* join the session */
272 ret
= join_session_keyring(name
);
278 } /* end keyctl_join_session_keyring() */
280 /*****************************************************************************/
282 * update a key's data payload
283 * - the key must be writable
284 * - implements keyctl(KEYCTL_UPDATE)
286 long keyctl_update_key(key_serial_t id
,
287 const void __user
*_payload
,
295 if (plen
> PAGE_SIZE
)
298 /* pull the payload in if one was supplied */
302 payload
= kmalloc(plen
, GFP_KERNEL
);
307 if (copy_from_user(payload
, _payload
, plen
) != 0)
311 /* find the target key (which must be writable) */
312 key_ref
= lookup_user_key(NULL
, id
, 0, 0, KEY_WRITE
);
313 if (IS_ERR(key_ref
)) {
314 ret
= PTR_ERR(key_ref
);
319 ret
= key_update(key_ref
, payload
, plen
);
321 key_ref_put(key_ref
);
327 } /* end keyctl_update_key() */
329 /*****************************************************************************/
332 * - the key must be writable
333 * - implements keyctl(KEYCTL_REVOKE)
335 long keyctl_revoke_key(key_serial_t id
)
340 key_ref
= lookup_user_key(NULL
, id
, 0, 0, KEY_WRITE
);
341 if (IS_ERR(key_ref
)) {
342 ret
= PTR_ERR(key_ref
);
346 key_revoke(key_ref_to_ptr(key_ref
));
349 key_ref_put(key_ref
);
353 } /* end keyctl_revoke_key() */
355 /*****************************************************************************/
357 * clear the specified process keyring
358 * - the keyring must be writable
359 * - implements keyctl(KEYCTL_CLEAR)
361 long keyctl_keyring_clear(key_serial_t ringid
)
363 key_ref_t keyring_ref
;
366 keyring_ref
= lookup_user_key(NULL
, ringid
, 1, 0, KEY_WRITE
);
367 if (IS_ERR(keyring_ref
)) {
368 ret
= PTR_ERR(keyring_ref
);
372 ret
= keyring_clear(key_ref_to_ptr(keyring_ref
));
374 key_ref_put(keyring_ref
);
378 } /* end keyctl_keyring_clear() */
380 /*****************************************************************************/
382 * link a key into a keyring
383 * - the keyring must be writable
384 * - the key must be linkable
385 * - implements keyctl(KEYCTL_LINK)
387 long keyctl_keyring_link(key_serial_t id
, key_serial_t ringid
)
389 key_ref_t keyring_ref
, key_ref
;
392 keyring_ref
= lookup_user_key(NULL
, ringid
, 1, 0, KEY_WRITE
);
393 if (IS_ERR(keyring_ref
)) {
394 ret
= PTR_ERR(keyring_ref
);
398 key_ref
= lookup_user_key(NULL
, id
, 1, 0, KEY_LINK
);
399 if (IS_ERR(key_ref
)) {
400 ret
= PTR_ERR(key_ref
);
404 ret
= key_link(key_ref_to_ptr(keyring_ref
), key_ref_to_ptr(key_ref
));
406 key_ref_put(key_ref
);
408 key_ref_put(keyring_ref
);
412 } /* end keyctl_keyring_link() */
414 /*****************************************************************************/
416 * unlink the first attachment of a key from a keyring
417 * - the keyring must be writable
418 * - we don't need any permissions on the key
419 * - implements keyctl(KEYCTL_UNLINK)
421 long keyctl_keyring_unlink(key_serial_t id
, key_serial_t ringid
)
423 key_ref_t keyring_ref
, key_ref
;
426 keyring_ref
= lookup_user_key(NULL
, ringid
, 0, 0, KEY_WRITE
);
427 if (IS_ERR(keyring_ref
)) {
428 ret
= PTR_ERR(keyring_ref
);
432 key_ref
= lookup_user_key(NULL
, id
, 0, 0, 0);
433 if (IS_ERR(key_ref
)) {
434 ret
= PTR_ERR(key_ref
);
438 ret
= key_unlink(key_ref_to_ptr(keyring_ref
), key_ref_to_ptr(key_ref
));
440 key_ref_put(key_ref
);
442 key_ref_put(keyring_ref
);
446 } /* end keyctl_keyring_unlink() */
448 /*****************************************************************************/
450 * describe a user key
451 * - the key must have view permission
452 * - if there's a buffer, we place up to buflen bytes of data into it
453 * - unless there's an error, we return the amount of description available,
454 * irrespective of how much we may have copied
455 * - the description is formatted thus:
456 * type;uid;gid;perm;description<NUL>
457 * - implements keyctl(KEYCTL_DESCRIBE)
459 long keyctl_describe_key(key_serial_t keyid
,
463 struct key
*key
, *instkey
;
468 key_ref
= lookup_user_key(NULL
, keyid
, 0, 1, KEY_VIEW
);
469 if (IS_ERR(key_ref
)) {
470 /* viewing a key under construction is permitted if we have the
471 * authorisation token handy */
472 if (PTR_ERR(key_ref
) == -EACCES
) {
473 instkey
= key_get_instantiation_authkey(keyid
);
474 if (!IS_ERR(instkey
)) {
476 key_ref
= lookup_user_key(NULL
, keyid
,
478 if (!IS_ERR(key_ref
))
483 ret
= PTR_ERR(key_ref
);
488 /* calculate how much description we're going to return */
490 tmpbuf
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
494 key
= key_ref_to_ptr(key_ref
);
496 ret
= snprintf(tmpbuf
, PAGE_SIZE
- 1,
498 key_ref_to_ptr(key_ref
)->type
->name
,
499 key_ref_to_ptr(key_ref
)->uid
,
500 key_ref_to_ptr(key_ref
)->gid
,
501 key_ref_to_ptr(key_ref
)->perm
,
502 key_ref_to_ptr(key_ref
)->description
?
503 key_ref_to_ptr(key_ref
)->description
: ""
506 /* include a NUL char at the end of the data */
507 if (ret
> PAGE_SIZE
- 1)
512 /* consider returning the data */
513 if (buffer
&& buflen
> 0) {
517 if (copy_to_user(buffer
, tmpbuf
, buflen
) != 0)
523 key_ref_put(key_ref
);
527 } /* end keyctl_describe_key() */
529 /*****************************************************************************/
531 * search the specified keyring for a matching key
532 * - the start keyring must be searchable
533 * - nested keyrings may also be searched if they are searchable
534 * - only keys with search permission may be found
535 * - if a key is found, it will be attached to the destination keyring if
536 * there's one specified
537 * - implements keyctl(KEYCTL_SEARCH)
539 long keyctl_keyring_search(key_serial_t ringid
,
540 const char __user
*_type
,
541 const char __user
*_description
,
542 key_serial_t destringid
)
544 struct key_type
*ktype
;
545 key_ref_t keyring_ref
, key_ref
, dest_ref
;
546 char type
[32], *description
;
549 /* pull the type and description into kernel space */
550 ret
= key_get_type_from_user(type
, _type
, sizeof(type
));
554 description
= strndup_user(_description
, PAGE_SIZE
);
555 if (IS_ERR(description
)) {
556 ret
= PTR_ERR(description
);
560 /* get the keyring at which to begin the search */
561 keyring_ref
= lookup_user_key(NULL
, ringid
, 0, 0, KEY_SEARCH
);
562 if (IS_ERR(keyring_ref
)) {
563 ret
= PTR_ERR(keyring_ref
);
567 /* get the destination keyring if specified */
570 dest_ref
= lookup_user_key(NULL
, destringid
, 1, 0, KEY_WRITE
);
571 if (IS_ERR(dest_ref
)) {
572 ret
= PTR_ERR(dest_ref
);
577 /* find the key type */
578 ktype
= key_type_lookup(type
);
580 ret
= PTR_ERR(ktype
);
585 key_ref
= keyring_search(keyring_ref
, ktype
, description
);
586 if (IS_ERR(key_ref
)) {
587 ret
= PTR_ERR(key_ref
);
589 /* treat lack or presence of a negative key the same */
595 /* link the resulting key to the destination keyring if we can */
597 ret
= key_permission(key_ref
, KEY_LINK
);
601 ret
= key_link(key_ref_to_ptr(dest_ref
), key_ref_to_ptr(key_ref
));
606 ret
= key_ref_to_ptr(key_ref
)->serial
;
609 key_ref_put(key_ref
);
613 key_ref_put(dest_ref
);
615 key_ref_put(keyring_ref
);
621 } /* end keyctl_keyring_search() */
623 /*****************************************************************************/
625 * read a user key's payload
626 * - the keyring must be readable or the key must be searchable from the
628 * - if there's a buffer, we place up to buflen bytes of data into it
629 * - unless there's an error, we return the amount of data in the key,
630 * irrespective of how much we may have copied
631 * - implements keyctl(KEYCTL_READ)
633 long keyctl_read_key(key_serial_t keyid
, char __user
*buffer
, size_t buflen
)
639 /* find the key first */
640 key_ref
= lookup_user_key(NULL
, keyid
, 0, 0, 0);
641 if (IS_ERR(key_ref
)) {
646 key
= key_ref_to_ptr(key_ref
);
648 /* see if we can read it directly */
649 ret
= key_permission(key_ref
, KEY_READ
);
655 /* we can't; see if it's searchable from this process's keyrings
656 * - we automatically take account of the fact that it may be
657 * dangling off an instantiation key
659 if (!is_key_possessed(key_ref
)) {
664 /* the key is probably readable - now try to read it */
666 ret
= key_validate(key
);
669 if (key
->type
->read
) {
670 /* read the data with the semaphore held (since we
672 down_read(&key
->sem
);
673 ret
= key
->type
->read(key
, buffer
, buflen
);
683 } /* end keyctl_read_key() */
685 /*****************************************************************************/
687 * change the ownership of a key
688 * - the keyring owned by the changer
689 * - if the uid or gid is -1, then that parameter is not changed
690 * - implements keyctl(KEYCTL_CHOWN)
692 long keyctl_chown_key(key_serial_t id
, uid_t uid
, gid_t gid
)
694 struct key_user
*newowner
, *zapowner
= NULL
;
700 if (uid
== (uid_t
) -1 && gid
== (gid_t
) -1)
703 key_ref
= lookup_user_key(NULL
, id
, 1, 1, KEY_SETATTR
);
704 if (IS_ERR(key_ref
)) {
705 ret
= PTR_ERR(key_ref
);
709 key
= key_ref_to_ptr(key_ref
);
711 /* make the changes with the locks held to prevent chown/chown races */
713 down_write(&key
->sem
);
715 if (!capable(CAP_SYS_ADMIN
)) {
716 /* only the sysadmin can chown a key to some other UID */
717 if (uid
!= (uid_t
) -1 && key
->uid
!= uid
)
720 /* only the sysadmin can set the key's GID to a group other
721 * than one of those that the current process subscribes to */
722 if (gid
!= (gid_t
) -1 && gid
!= key
->gid
&& !in_group_p(gid
))
727 if (uid
!= (uid_t
) -1 && uid
!= key
->uid
) {
729 newowner
= key_user_lookup(uid
);
733 /* transfer the quota burden to the new user */
734 if (test_bit(KEY_FLAG_IN_QUOTA
, &key
->flags
)) {
735 unsigned maxkeys
= (uid
== 0) ?
736 key_quota_root_maxkeys
: key_quota_maxkeys
;
737 unsigned maxbytes
= (uid
== 0) ?
738 key_quota_root_maxbytes
: key_quota_maxbytes
;
740 spin_lock(&newowner
->lock
);
741 if (newowner
->qnkeys
+ 1 >= maxkeys
||
742 newowner
->qnbytes
+ key
->quotalen
>= maxbytes
||
743 newowner
->qnbytes
+ key
->quotalen
<
748 newowner
->qnbytes
+= key
->quotalen
;
749 spin_unlock(&newowner
->lock
);
751 spin_lock(&key
->user
->lock
);
753 key
->user
->qnbytes
-= key
->quotalen
;
754 spin_unlock(&key
->user
->lock
);
757 atomic_dec(&key
->user
->nkeys
);
758 atomic_inc(&newowner
->nkeys
);
760 if (test_bit(KEY_FLAG_INSTANTIATED
, &key
->flags
)) {
761 atomic_dec(&key
->user
->nikeys
);
762 atomic_inc(&newowner
->nikeys
);
765 zapowner
= key
->user
;
766 key
->user
= newowner
;
771 if (gid
!= (gid_t
) -1)
780 key_user_put(zapowner
);
785 spin_unlock(&newowner
->lock
);
790 } /* end keyctl_chown_key() */
792 /*****************************************************************************/
794 * change the permission mask on a key
795 * - the keyring owned by the changer
796 * - implements keyctl(KEYCTL_SETPERM)
798 long keyctl_setperm_key(key_serial_t id
, key_perm_t perm
)
805 if (perm
& ~(KEY_POS_ALL
| KEY_USR_ALL
| KEY_GRP_ALL
| KEY_OTH_ALL
))
808 key_ref
= lookup_user_key(NULL
, id
, 1, 1, KEY_SETATTR
);
809 if (IS_ERR(key_ref
)) {
810 ret
= PTR_ERR(key_ref
);
814 key
= key_ref_to_ptr(key_ref
);
816 /* make the changes with the locks held to prevent chown/chmod races */
818 down_write(&key
->sem
);
820 /* if we're not the sysadmin, we can only change a key that we own */
821 if (capable(CAP_SYS_ADMIN
) || key
->uid
== current
->fsuid
) {
831 } /* end keyctl_setperm_key() */
833 /*****************************************************************************/
835 * instantiate the key with the specified payload, and, if one is given, link
836 * the key into the keyring
838 long keyctl_instantiate_key(key_serial_t id
,
839 const void __user
*_payload
,
843 struct request_key_auth
*rka
;
845 key_ref_t keyring_ref
;
851 if (plen
> 1024 * 1024 - 1)
854 /* the appropriate instantiation authorisation key must have been
855 * assumed before calling this */
857 instkey
= current
->request_key_auth
;
861 rka
= instkey
->payload
.data
;
862 if (rka
->target_key
->serial
!= id
)
865 /* pull the payload in if one was supplied */
870 payload
= kmalloc(plen
, GFP_KERNEL
);
872 if (plen
<= PAGE_SIZE
)
875 payload
= vmalloc(plen
);
881 if (copy_from_user(payload
, _payload
, plen
) != 0)
885 /* find the destination keyring amongst those belonging to the
889 keyring_ref
= lookup_user_key(rka
->context
, ringid
, 1, 0,
891 if (IS_ERR(keyring_ref
)) {
892 ret
= PTR_ERR(keyring_ref
);
897 /* instantiate the key and link it into a keyring */
898 ret
= key_instantiate_and_link(rka
->target_key
, payload
, plen
,
899 key_ref_to_ptr(keyring_ref
), instkey
);
901 key_ref_put(keyring_ref
);
903 /* discard the assumed authority if it's just been disabled by
904 * instantiation of the key */
906 key_put(current
->request_key_auth
);
907 current
->request_key_auth
= NULL
;
918 } /* end keyctl_instantiate_key() */
920 /*****************************************************************************/
922 * negatively instantiate the key with the given timeout (in seconds), and, if
923 * one is given, link the key into the keyring
925 long keyctl_negate_key(key_serial_t id
, unsigned timeout
, key_serial_t ringid
)
927 struct request_key_auth
*rka
;
929 key_ref_t keyring_ref
;
932 /* the appropriate instantiation authorisation key must have been
933 * assumed before calling this */
935 instkey
= current
->request_key_auth
;
939 rka
= instkey
->payload
.data
;
940 if (rka
->target_key
->serial
!= id
)
943 /* find the destination keyring if present (which must also be
947 keyring_ref
= lookup_user_key(NULL
, ringid
, 1, 0, KEY_WRITE
);
948 if (IS_ERR(keyring_ref
)) {
949 ret
= PTR_ERR(keyring_ref
);
954 /* instantiate the key and link it into a keyring */
955 ret
= key_negate_and_link(rka
->target_key
, timeout
,
956 key_ref_to_ptr(keyring_ref
), instkey
);
958 key_ref_put(keyring_ref
);
960 /* discard the assumed authority if it's just been disabled by
961 * instantiation of the key */
963 key_put(current
->request_key_auth
);
964 current
->request_key_auth
= NULL
;
970 } /* end keyctl_negate_key() */
972 /*****************************************************************************/
974 * set the default keyring in which request_key() will cache keys
975 * - return the old setting
977 long keyctl_set_reqkey_keyring(int reqkey_defl
)
981 switch (reqkey_defl
) {
982 case KEY_REQKEY_DEFL_THREAD_KEYRING
:
983 ret
= install_thread_keyring(current
);
988 case KEY_REQKEY_DEFL_PROCESS_KEYRING
:
989 ret
= install_process_keyring(current
);
993 case KEY_REQKEY_DEFL_DEFAULT
:
994 case KEY_REQKEY_DEFL_SESSION_KEYRING
:
995 case KEY_REQKEY_DEFL_USER_KEYRING
:
996 case KEY_REQKEY_DEFL_USER_SESSION_KEYRING
:
998 current
->jit_keyring
= reqkey_defl
;
1000 case KEY_REQKEY_DEFL_NO_CHANGE
:
1001 return current
->jit_keyring
;
1003 case KEY_REQKEY_DEFL_GROUP_KEYRING
:
1008 } /* end keyctl_set_reqkey_keyring() */
1010 /*****************************************************************************/
1012 * set or clear the timeout for a key
1014 long keyctl_set_timeout(key_serial_t id
, unsigned timeout
)
1016 struct timespec now
;
1022 key_ref
= lookup_user_key(NULL
, id
, 1, 1, KEY_SETATTR
);
1023 if (IS_ERR(key_ref
)) {
1024 ret
= PTR_ERR(key_ref
);
1028 key
= key_ref_to_ptr(key_ref
);
1030 /* make the changes with the locks held to prevent races */
1031 down_write(&key
->sem
);
1035 now
= current_kernel_time();
1036 expiry
= now
.tv_sec
+ timeout
;
1039 key
->expiry
= expiry
;
1041 up_write(&key
->sem
);
1048 } /* end keyctl_set_timeout() */
1050 /*****************************************************************************/
1052 * assume the authority to instantiate the specified key
1054 long keyctl_assume_authority(key_serial_t id
)
1056 struct key
*authkey
;
1059 /* special key IDs aren't permitted */
1064 /* we divest ourselves of authority if given an ID of 0 */
1066 key_put(current
->request_key_auth
);
1067 current
->request_key_auth
= NULL
;
1072 /* attempt to assume the authority temporarily granted to us whilst we
1073 * instantiate the specified key
1074 * - the authorisation key must be in the current task's keyrings
1077 authkey
= key_get_instantiation_authkey(id
);
1078 if (IS_ERR(authkey
)) {
1079 ret
= PTR_ERR(authkey
);
1083 key_put(current
->request_key_auth
);
1084 current
->request_key_auth
= authkey
;
1085 ret
= authkey
->serial
;
1090 } /* end keyctl_assume_authority() */
1093 * get the security label of a key
1094 * - the key must grant us view permission
1095 * - if there's a buffer, we place up to buflen bytes of data into it
1096 * - unless there's an error, we return the amount of information available,
1097 * irrespective of how much we may have copied (including the terminal NUL)
1098 * - implements keyctl(KEYCTL_GET_SECURITY)
1100 long keyctl_get_security(key_serial_t keyid
,
1101 char __user
*buffer
,
1104 struct key
*key
, *instkey
;
1109 key_ref
= lookup_user_key(NULL
, keyid
, 0, 1, KEY_VIEW
);
1110 if (IS_ERR(key_ref
)) {
1111 if (PTR_ERR(key_ref
) != -EACCES
)
1112 return PTR_ERR(key_ref
);
1114 /* viewing a key under construction is also permitted if we
1115 * have the authorisation token handy */
1116 instkey
= key_get_instantiation_authkey(keyid
);
1117 if (IS_ERR(instkey
))
1118 return PTR_ERR(key_ref
);
1121 key_ref
= lookup_user_key(NULL
, keyid
, 0, 1, 0);
1122 if (IS_ERR(key_ref
))
1123 return PTR_ERR(key_ref
);
1126 key
= key_ref_to_ptr(key_ref
);
1127 ret
= security_key_getsecurity(key
, &context
);
1129 /* if no information was returned, give userspace an empty
1132 if (buffer
&& buflen
> 0 &&
1133 copy_to_user(buffer
, "", 1) != 0)
1135 } else if (ret
> 0) {
1136 /* return as much data as there's room for */
1137 if (buffer
&& buflen
> 0) {
1141 if (copy_to_user(buffer
, context
, buflen
) != 0)
1148 key_ref_put(key_ref
);
1152 /*****************************************************************************/
1154 * the key control system call
1156 SYSCALL_DEFINE5(keyctl
, int, option
, unsigned long, arg2
, unsigned long, arg3
,
1157 unsigned long, arg4
, unsigned long, arg5
)
1160 case KEYCTL_GET_KEYRING_ID
:
1161 return keyctl_get_keyring_ID((key_serial_t
) arg2
,
1164 case KEYCTL_JOIN_SESSION_KEYRING
:
1165 return keyctl_join_session_keyring((const char __user
*) arg2
);
1168 return keyctl_update_key((key_serial_t
) arg2
,
1169 (const void __user
*) arg3
,
1173 return keyctl_revoke_key((key_serial_t
) arg2
);
1175 case KEYCTL_DESCRIBE
:
1176 return keyctl_describe_key((key_serial_t
) arg2
,
1177 (char __user
*) arg3
,
1181 return keyctl_keyring_clear((key_serial_t
) arg2
);
1184 return keyctl_keyring_link((key_serial_t
) arg2
,
1185 (key_serial_t
) arg3
);
1188 return keyctl_keyring_unlink((key_serial_t
) arg2
,
1189 (key_serial_t
) arg3
);
1192 return keyctl_keyring_search((key_serial_t
) arg2
,
1193 (const char __user
*) arg3
,
1194 (const char __user
*) arg4
,
1195 (key_serial_t
) arg5
);
1198 return keyctl_read_key((key_serial_t
) arg2
,
1199 (char __user
*) arg3
,
1203 return keyctl_chown_key((key_serial_t
) arg2
,
1207 case KEYCTL_SETPERM
:
1208 return keyctl_setperm_key((key_serial_t
) arg2
,
1211 case KEYCTL_INSTANTIATE
:
1212 return keyctl_instantiate_key((key_serial_t
) arg2
,
1213 (const void __user
*) arg3
,
1215 (key_serial_t
) arg5
);
1218 return keyctl_negate_key((key_serial_t
) arg2
,
1220 (key_serial_t
) arg4
);
1222 case KEYCTL_SET_REQKEY_KEYRING
:
1223 return keyctl_set_reqkey_keyring(arg2
);
1225 case KEYCTL_SET_TIMEOUT
:
1226 return keyctl_set_timeout((key_serial_t
) arg2
,
1229 case KEYCTL_ASSUME_AUTHORITY
:
1230 return keyctl_assume_authority((key_serial_t
) arg2
);
1232 case KEYCTL_GET_SECURITY
:
1233 return keyctl_get_security((key_serial_t
) arg2
,
1241 } /* end sys_keyctl() */