4 * UID and GID to name mapping for clients.
6 * Copyright (c) 2002 The Regents of the University of Michigan.
9 * Marius Aamodt Eriksen <marius@umich.edu>
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <linux/types.h>
37 #include <linux/string.h>
38 #include <linux/kernel.h>
39 #include <linux/slab.h>
40 #include <linux/nfs_idmap.h>
42 static int nfs_map_string_to_numeric(const char *name
, size_t namelen
, __u32
*res
)
47 if (memchr(name
, '@', namelen
) != NULL
|| namelen
>= sizeof(buf
))
49 memcpy(buf
, name
, namelen
);
51 if (strict_strtoul(buf
, 0, &val
) != 0)
57 static int nfs_map_numeric_to_string(__u32 id
, char *buf
, size_t buflen
)
59 return snprintf(buf
, buflen
, "%u", id
);
62 #ifdef CONFIG_NFS_USE_NEW_IDMAPPER
64 #include <linux/cred.h>
65 #include <linux/sunrpc/sched.h>
66 #include <linux/nfs4.h>
67 #include <linux/nfs_fs_sb.h>
68 #include <linux/keyctl.h>
69 #include <linux/key-type.h>
70 #include <linux/rcupdate.h>
71 #include <linux/err.h>
73 #include <keys/user-type.h>
75 #define NFS_UINT_MAXLEN 11
77 const struct cred
*id_resolver_cache
;
79 struct key_type key_type_id_resolver
= {
80 .name
= "id_resolver",
81 .instantiate
= user_instantiate
,
83 .revoke
= user_revoke
,
84 .destroy
= user_destroy
,
85 .describe
= user_describe
,
89 int nfs_idmap_init(void)
95 printk(KERN_NOTICE
"Registering the %s key type\n", key_type_id_resolver
.name
);
97 cred
= prepare_kernel_cred(NULL
);
101 keyring
= key_alloc(&key_type_keyring
, ".id_resolver", 0, 0, cred
,
102 (KEY_POS_ALL
& ~KEY_POS_SETATTR
) |
103 KEY_USR_VIEW
| KEY_USR_READ
,
104 KEY_ALLOC_NOT_IN_QUOTA
);
105 if (IS_ERR(keyring
)) {
106 ret
= PTR_ERR(keyring
);
107 goto failed_put_cred
;
110 ret
= key_instantiate_and_link(keyring
, NULL
, 0, NULL
, NULL
);
114 ret
= register_key_type(&key_type_id_resolver
);
118 cred
->thread_keyring
= keyring
;
119 cred
->jit_keyring
= KEY_REQKEY_DEFL_THREAD_KEYRING
;
120 id_resolver_cache
= cred
;
130 void nfs_idmap_quit(void)
132 key_revoke(id_resolver_cache
->thread_keyring
);
133 unregister_key_type(&key_type_id_resolver
);
134 put_cred(id_resolver_cache
);
138 * Assemble the description to pass to request_key()
139 * This function will allocate a new string and update dest to point
140 * at it. The caller is responsible for freeing dest.
142 * On error 0 is returned. Otherwise, the length of dest is returned.
144 static ssize_t
nfs_idmap_get_desc(const char *name
, size_t namelen
,
145 const char *type
, size_t typelen
, char **desc
)
148 size_t desclen
= typelen
+ namelen
+ 2;
150 *desc
= kmalloc(desclen
, GFP_KERNEL
);
155 memcpy(cp
, type
, typelen
);
159 memcpy(cp
, name
, namelen
);
165 static ssize_t
nfs_idmap_request_key(const char *name
, size_t namelen
,
166 const char *type
, void *data
, size_t data_size
)
168 const struct cred
*saved_cred
;
171 struct user_key_payload
*payload
;
174 ret
= nfs_idmap_get_desc(name
, namelen
, type
, strlen(type
), &desc
);
178 saved_cred
= override_creds(id_resolver_cache
);
179 rkey
= request_key(&key_type_id_resolver
, desc
, "");
180 revert_creds(saved_cred
);
188 rkey
->perm
|= KEY_USR_VIEW
;
190 ret
= key_validate(rkey
);
194 payload
= rcu_dereference(rkey
->payload
.data
);
195 if (IS_ERR_OR_NULL(payload
)) {
196 ret
= PTR_ERR(payload
);
200 ret
= payload
->datalen
;
201 if (ret
> 0 && ret
<= data_size
)
202 memcpy(data
, payload
->data
, ret
);
215 static ssize_t
nfs_idmap_lookup_name(__u32 id
, const char *type
, char *buf
, size_t buflen
)
217 char id_str
[NFS_UINT_MAXLEN
];
221 id_len
= snprintf(id_str
, sizeof(id_str
), "%u", id
);
222 ret
= nfs_idmap_request_key(id_str
, id_len
, type
, buf
, buflen
);
229 static int nfs_idmap_lookup_id(const char *name
, size_t namelen
,
230 const char *type
, __u32
*id
)
232 char id_str
[NFS_UINT_MAXLEN
];
237 data_size
= nfs_idmap_request_key(name
, namelen
, type
, id_str
, NFS_UINT_MAXLEN
);
238 if (data_size
<= 0) {
241 ret
= strict_strtol(id_str
, 10, &id_long
);
242 *id
= (__u32
)id_long
;
247 int nfs_map_name_to_uid(const struct nfs_server
*server
, const char *name
, size_t namelen
, __u32
*uid
)
249 if (nfs_map_string_to_numeric(name
, namelen
, uid
))
251 return nfs_idmap_lookup_id(name
, namelen
, "uid", uid
);
254 int nfs_map_group_to_gid(const struct nfs_server
*server
, const char *name
, size_t namelen
, __u32
*gid
)
256 if (nfs_map_string_to_numeric(name
, namelen
, gid
))
258 return nfs_idmap_lookup_id(name
, namelen
, "gid", gid
);
261 int nfs_map_uid_to_name(const struct nfs_server
*server
, __u32 uid
, char *buf
, size_t buflen
)
265 if (!(server
->caps
& NFS_CAP_UIDGID_NOMAP
))
266 ret
= nfs_idmap_lookup_name(uid
, "user", buf
, buflen
);
268 ret
= nfs_map_numeric_to_string(uid
, buf
, buflen
);
271 int nfs_map_gid_to_group(const struct nfs_server
*server
, __u32 gid
, char *buf
, size_t buflen
)
275 if (!(server
->caps
& NFS_CAP_UIDGID_NOMAP
))
276 ret
= nfs_idmap_lookup_name(gid
, "group", buf
, buflen
);
278 ret
= nfs_map_numeric_to_string(gid
, buf
, buflen
);
282 #else /* CONFIG_NFS_USE_NEW_IDMAPPER not defined */
284 #include <linux/module.h>
285 #include <linux/mutex.h>
286 #include <linux/init.h>
287 #include <linux/socket.h>
288 #include <linux/in.h>
289 #include <linux/sched.h>
290 #include <linux/sunrpc/clnt.h>
291 #include <linux/workqueue.h>
292 #include <linux/sunrpc/rpc_pipe_fs.h>
294 #include <linux/nfs_fs.h>
298 #define IDMAP_HASH_SZ 128
300 /* Default cache timeout is 10 minutes */
301 unsigned int nfs_idmap_cache_timeout
= 600 * HZ
;
303 static int param_set_idmap_timeout(const char *val
, struct kernel_param
*kp
)
306 int num
= simple_strtol(val
, &endp
, 0);
308 if (endp
== val
|| *endp
|| num
< 0 || jif
< num
)
310 *((int *)kp
->arg
) = jif
;
314 module_param_call(idmap_cache_timeout
, param_set_idmap_timeout
, param_get_int
,
315 &nfs_idmap_cache_timeout
, 0644);
317 struct idmap_hashent
{
318 unsigned long ih_expires
;
321 char ih_name
[IDMAP_NAMESZ
];
324 struct idmap_hashtable
{
326 struct idmap_hashent h_entries
[IDMAP_HASH_SZ
];
330 struct dentry
*idmap_dentry
;
331 wait_queue_head_t idmap_wq
;
332 struct idmap_msg idmap_im
;
333 struct mutex idmap_lock
; /* Serializes upcalls */
334 struct mutex idmap_im_lock
; /* Protects the hashtable */
335 struct idmap_hashtable idmap_user_hash
;
336 struct idmap_hashtable idmap_group_hash
;
339 static ssize_t
idmap_pipe_downcall(struct file
*, const char __user
*,
341 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg
*);
343 static unsigned int fnvhash32(const void *, size_t);
345 static const struct rpc_pipe_ops idmap_upcall_ops
= {
346 .upcall
= rpc_pipe_generic_upcall
,
347 .downcall
= idmap_pipe_downcall
,
348 .destroy_msg
= idmap_pipe_destroy_msg
,
352 nfs_idmap_new(struct nfs_client
*clp
)
357 BUG_ON(clp
->cl_idmap
!= NULL
);
359 idmap
= kzalloc(sizeof(*idmap
), GFP_KERNEL
);
363 idmap
->idmap_dentry
= rpc_mkpipe(clp
->cl_rpcclient
->cl_path
.dentry
,
364 "idmap", idmap
, &idmap_upcall_ops
, 0);
365 if (IS_ERR(idmap
->idmap_dentry
)) {
366 error
= PTR_ERR(idmap
->idmap_dentry
);
371 mutex_init(&idmap
->idmap_lock
);
372 mutex_init(&idmap
->idmap_im_lock
);
373 init_waitqueue_head(&idmap
->idmap_wq
);
374 idmap
->idmap_user_hash
.h_type
= IDMAP_TYPE_USER
;
375 idmap
->idmap_group_hash
.h_type
= IDMAP_TYPE_GROUP
;
377 clp
->cl_idmap
= idmap
;
382 nfs_idmap_delete(struct nfs_client
*clp
)
384 struct idmap
*idmap
= clp
->cl_idmap
;
388 rpc_unlink(idmap
->idmap_dentry
);
389 clp
->cl_idmap
= NULL
;
394 * Helper routines for manipulating the hashtable
396 static inline struct idmap_hashent
*
397 idmap_name_hash(struct idmap_hashtable
* h
, const char *name
, size_t len
)
399 return &h
->h_entries
[fnvhash32(name
, len
) % IDMAP_HASH_SZ
];
402 static struct idmap_hashent
*
403 idmap_lookup_name(struct idmap_hashtable
*h
, const char *name
, size_t len
)
405 struct idmap_hashent
*he
= idmap_name_hash(h
, name
, len
);
407 if (he
->ih_namelen
!= len
|| memcmp(he
->ih_name
, name
, len
) != 0)
409 if (time_after(jiffies
, he
->ih_expires
))
414 static inline struct idmap_hashent
*
415 idmap_id_hash(struct idmap_hashtable
* h
, __u32 id
)
417 return &h
->h_entries
[fnvhash32(&id
, sizeof(id
)) % IDMAP_HASH_SZ
];
420 static struct idmap_hashent
*
421 idmap_lookup_id(struct idmap_hashtable
*h
, __u32 id
)
423 struct idmap_hashent
*he
= idmap_id_hash(h
, id
);
424 if (he
->ih_id
!= id
|| he
->ih_namelen
== 0)
426 if (time_after(jiffies
, he
->ih_expires
))
432 * Routines for allocating new entries in the hashtable.
433 * For now, we just have 1 entry per bucket, so it's all
436 static inline struct idmap_hashent
*
437 idmap_alloc_name(struct idmap_hashtable
*h
, char *name
, size_t len
)
439 return idmap_name_hash(h
, name
, len
);
442 static inline struct idmap_hashent
*
443 idmap_alloc_id(struct idmap_hashtable
*h
, __u32 id
)
445 return idmap_id_hash(h
, id
);
449 idmap_update_entry(struct idmap_hashent
*he
, const char *name
,
450 size_t namelen
, __u32 id
)
453 memcpy(he
->ih_name
, name
, namelen
);
454 he
->ih_name
[namelen
] = '\0';
455 he
->ih_namelen
= namelen
;
456 he
->ih_expires
= jiffies
+ nfs_idmap_cache_timeout
;
463 nfs_idmap_id(struct idmap
*idmap
, struct idmap_hashtable
*h
,
464 const char *name
, size_t namelen
, __u32
*id
)
466 struct rpc_pipe_msg msg
;
467 struct idmap_msg
*im
;
468 struct idmap_hashent
*he
;
469 DECLARE_WAITQUEUE(wq
, current
);
472 im
= &idmap
->idmap_im
;
475 * String sanity checks
476 * Note that the userland daemon expects NUL terminated strings
481 if (name
[namelen
-1] != '\0')
485 if (namelen
>= IDMAP_NAMESZ
)
488 mutex_lock(&idmap
->idmap_lock
);
489 mutex_lock(&idmap
->idmap_im_lock
);
491 he
= idmap_lookup_name(h
, name
, namelen
);
498 memset(im
, 0, sizeof(*im
));
499 memcpy(im
->im_name
, name
, namelen
);
501 im
->im_type
= h
->h_type
;
502 im
->im_conv
= IDMAP_CONV_NAMETOID
;
504 memset(&msg
, 0, sizeof(msg
));
506 msg
.len
= sizeof(*im
);
508 add_wait_queue(&idmap
->idmap_wq
, &wq
);
509 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
510 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
514 set_current_state(TASK_UNINTERRUPTIBLE
);
515 mutex_unlock(&idmap
->idmap_im_lock
);
517 __set_current_state(TASK_RUNNING
);
518 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
519 mutex_lock(&idmap
->idmap_im_lock
);
521 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
527 memset(im
, 0, sizeof(*im
));
528 mutex_unlock(&idmap
->idmap_im_lock
);
529 mutex_unlock(&idmap
->idmap_lock
);
537 nfs_idmap_name(struct idmap
*idmap
, struct idmap_hashtable
*h
,
538 __u32 id
, char *name
)
540 struct rpc_pipe_msg msg
;
541 struct idmap_msg
*im
;
542 struct idmap_hashent
*he
;
543 DECLARE_WAITQUEUE(wq
, current
);
547 im
= &idmap
->idmap_im
;
549 mutex_lock(&idmap
->idmap_lock
);
550 mutex_lock(&idmap
->idmap_im_lock
);
552 he
= idmap_lookup_id(h
, id
);
554 memcpy(name
, he
->ih_name
, he
->ih_namelen
);
555 ret
= he
->ih_namelen
;
559 memset(im
, 0, sizeof(*im
));
560 im
->im_type
= h
->h_type
;
561 im
->im_conv
= IDMAP_CONV_IDTONAME
;
564 memset(&msg
, 0, sizeof(msg
));
566 msg
.len
= sizeof(*im
);
568 add_wait_queue(&idmap
->idmap_wq
, &wq
);
570 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
571 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
575 set_current_state(TASK_UNINTERRUPTIBLE
);
576 mutex_unlock(&idmap
->idmap_im_lock
);
578 __set_current_state(TASK_RUNNING
);
579 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
580 mutex_lock(&idmap
->idmap_im_lock
);
582 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
583 if ((len
= strnlen(im
->im_name
, IDMAP_NAMESZ
)) == 0)
585 memcpy(name
, im
->im_name
, len
);
590 memset(im
, 0, sizeof(*im
));
591 mutex_unlock(&idmap
->idmap_im_lock
);
592 mutex_unlock(&idmap
->idmap_lock
);
597 idmap_pipe_downcall(struct file
*filp
, const char __user
*src
, size_t mlen
)
599 struct rpc_inode
*rpci
= RPC_I(filp
->f_path
.dentry
->d_inode
);
600 struct idmap
*idmap
= (struct idmap
*)rpci
->private;
601 struct idmap_msg im_in
, *im
= &idmap
->idmap_im
;
602 struct idmap_hashtable
*h
;
603 struct idmap_hashent
*he
= NULL
;
607 if (mlen
!= sizeof(im_in
))
610 if (copy_from_user(&im_in
, src
, mlen
) != 0)
613 mutex_lock(&idmap
->idmap_im_lock
);
616 im
->im_status
= im_in
.im_status
;
617 /* If we got an error, terminate now, and wake up pending upcalls */
618 if (!(im_in
.im_status
& IDMAP_STATUS_SUCCESS
)) {
619 wake_up(&idmap
->idmap_wq
);
623 /* Sanity checking of strings */
625 namelen_in
= strnlen(im_in
.im_name
, IDMAP_NAMESZ
);
626 if (namelen_in
== 0 || namelen_in
== IDMAP_NAMESZ
)
629 switch (im_in
.im_type
) {
630 case IDMAP_TYPE_USER
:
631 h
= &idmap
->idmap_user_hash
;
633 case IDMAP_TYPE_GROUP
:
634 h
= &idmap
->idmap_group_hash
;
640 switch (im_in
.im_conv
) {
641 case IDMAP_CONV_IDTONAME
:
642 /* Did we match the current upcall? */
643 if (im
->im_conv
== IDMAP_CONV_IDTONAME
644 && im
->im_type
== im_in
.im_type
645 && im
->im_id
== im_in
.im_id
) {
646 /* Yes: copy string, including the terminating '\0' */
647 memcpy(im
->im_name
, im_in
.im_name
, namelen_in
);
648 im
->im_name
[namelen_in
] = '\0';
649 wake_up(&idmap
->idmap_wq
);
651 he
= idmap_alloc_id(h
, im_in
.im_id
);
653 case IDMAP_CONV_NAMETOID
:
654 /* Did we match the current upcall? */
655 if (im
->im_conv
== IDMAP_CONV_NAMETOID
656 && im
->im_type
== im_in
.im_type
657 && strnlen(im
->im_name
, IDMAP_NAMESZ
) == namelen_in
658 && memcmp(im
->im_name
, im_in
.im_name
, namelen_in
) == 0) {
659 im
->im_id
= im_in
.im_id
;
660 wake_up(&idmap
->idmap_wq
);
662 he
= idmap_alloc_name(h
, im_in
.im_name
, namelen_in
);
668 /* If the entry is valid, also copy it to the cache */
670 idmap_update_entry(he
, im_in
.im_name
, namelen_in
, im_in
.im_id
);
673 mutex_unlock(&idmap
->idmap_im_lock
);
678 idmap_pipe_destroy_msg(struct rpc_pipe_msg
*msg
)
680 struct idmap_msg
*im
= msg
->data
;
681 struct idmap
*idmap
= container_of(im
, struct idmap
, idmap_im
);
685 mutex_lock(&idmap
->idmap_im_lock
);
686 im
->im_status
= IDMAP_STATUS_LOOKUPFAIL
;
687 wake_up(&idmap
->idmap_wq
);
688 mutex_unlock(&idmap
->idmap_im_lock
);
692 * Fowler/Noll/Vo hash
693 * http://www.isthe.com/chongo/tech/comp/fnv/
696 #define FNV_P_32 ((unsigned int)0x01000193) /* 16777619 */
697 #define FNV_1_32 ((unsigned int)0x811c9dc5) /* 2166136261 */
699 static unsigned int fnvhash32(const void *buf
, size_t buflen
)
701 const unsigned char *p
, *end
= (const unsigned char *)buf
+ buflen
;
702 unsigned int hash
= FNV_1_32
;
704 for (p
= buf
; p
< end
; p
++) {
706 hash
^= (unsigned int)*p
;
712 int nfs_map_name_to_uid(const struct nfs_server
*server
, const char *name
, size_t namelen
, __u32
*uid
)
714 struct idmap
*idmap
= server
->nfs_client
->cl_idmap
;
716 if (nfs_map_string_to_numeric(name
, namelen
, uid
))
718 return nfs_idmap_id(idmap
, &idmap
->idmap_user_hash
, name
, namelen
, uid
);
721 int nfs_map_group_to_gid(const struct nfs_server
*server
, const char *name
, size_t namelen
, __u32
*uid
)
723 struct idmap
*idmap
= server
->nfs_client
->cl_idmap
;
725 if (nfs_map_string_to_numeric(name
, namelen
, uid
))
727 return nfs_idmap_id(idmap
, &idmap
->idmap_group_hash
, name
, namelen
, uid
);
730 int nfs_map_uid_to_name(const struct nfs_server
*server
, __u32 uid
, char *buf
, size_t buflen
)
732 struct idmap
*idmap
= server
->nfs_client
->cl_idmap
;
735 if (!(server
->caps
& NFS_CAP_UIDGID_NOMAP
))
736 ret
= nfs_idmap_name(idmap
, &idmap
->idmap_user_hash
, uid
, buf
);
738 ret
= nfs_map_numeric_to_string(uid
, buf
, buflen
);
741 int nfs_map_gid_to_group(const struct nfs_server
*server
, __u32 uid
, char *buf
, size_t buflen
)
743 struct idmap
*idmap
= server
->nfs_client
->cl_idmap
;
746 if (!(server
->caps
& NFS_CAP_UIDGID_NOMAP
))
747 ret
= nfs_idmap_name(idmap
, &idmap
->idmap_group_hash
, uid
, buf
);
749 ret
= nfs_map_numeric_to_string(uid
, buf
, buflen
);
753 #endif /* CONFIG_NFS_USE_NEW_IDMAPPER */