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.
37 #include <linux/module.h>
38 #include <linux/mutex.h>
39 #include <linux/init.h>
40 #include <linux/types.h>
41 #include <linux/slab.h>
42 #include <linux/socket.h>
44 #include <linux/sched.h>
46 #include <linux/sunrpc/clnt.h>
47 #include <linux/workqueue.h>
48 #include <linux/sunrpc/rpc_pipe_fs.h>
50 #include <linux/nfs_fs.h>
52 #include <linux/nfs_idmap.h>
55 #define IDMAP_HASH_SZ 128
57 /* Default cache timeout is 10 minutes */
58 unsigned int nfs_idmap_cache_timeout
= 600 * HZ
;
60 static int param_set_idmap_timeout(const char *val
, struct kernel_param
*kp
)
63 int num
= simple_strtol(val
, &endp
, 0);
65 if (endp
== val
|| *endp
|| num
< 0 || jif
< num
)
67 *((int *)kp
->arg
) = jif
;
71 module_param_call(idmap_cache_timeout
, param_set_idmap_timeout
, param_get_int
,
72 &nfs_idmap_cache_timeout
, 0644);
74 struct idmap_hashent
{
75 unsigned long ih_expires
;
78 char ih_name
[IDMAP_NAMESZ
];
81 struct idmap_hashtable
{
83 struct idmap_hashent h_entries
[IDMAP_HASH_SZ
];
88 struct dentry
*idmap_dentry
;
89 wait_queue_head_t idmap_wq
;
90 struct idmap_msg idmap_im
;
91 struct mutex idmap_lock
; /* Serializes upcalls */
92 struct mutex idmap_im_lock
; /* Protects the hashtable */
93 struct idmap_hashtable idmap_user_hash
;
94 struct idmap_hashtable idmap_group_hash
;
97 static ssize_t
idmap_pipe_upcall(struct file
*, struct rpc_pipe_msg
*,
98 char __user
*, size_t);
99 static ssize_t
idmap_pipe_downcall(struct file
*, const char __user
*,
101 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg
*);
103 static unsigned int fnvhash32(const void *, size_t);
105 static struct rpc_pipe_ops idmap_upcall_ops
= {
106 .upcall
= idmap_pipe_upcall
,
107 .downcall
= idmap_pipe_downcall
,
108 .destroy_msg
= idmap_pipe_destroy_msg
,
112 nfs_idmap_new(struct nfs_client
*clp
)
117 if (clp
->cl_idmap
!= NULL
)
120 if ((idmap
= kzalloc(sizeof(*idmap
), GFP_KERNEL
)) == NULL
)
123 snprintf(idmap
->idmap_path
, sizeof(idmap
->idmap_path
),
124 "%s/idmap", clp
->cl_rpcclient
->cl_pathname
);
126 idmap
->idmap_dentry
= rpc_mkpipe(idmap
->idmap_path
,
127 idmap
, &idmap_upcall_ops
, 0);
128 if (IS_ERR(idmap
->idmap_dentry
)) {
129 error
= PTR_ERR(idmap
->idmap_dentry
);
134 mutex_init(&idmap
->idmap_lock
);
135 mutex_init(&idmap
->idmap_im_lock
);
136 init_waitqueue_head(&idmap
->idmap_wq
);
137 idmap
->idmap_user_hash
.h_type
= IDMAP_TYPE_USER
;
138 idmap
->idmap_group_hash
.h_type
= IDMAP_TYPE_GROUP
;
140 clp
->cl_idmap
= idmap
;
145 nfs_idmap_delete(struct nfs_client
*clp
)
147 struct idmap
*idmap
= clp
->cl_idmap
;
151 rpc_unlink(idmap
->idmap_dentry
);
152 clp
->cl_idmap
= NULL
;
157 * Helper routines for manipulating the hashtable
159 static inline struct idmap_hashent
*
160 idmap_name_hash(struct idmap_hashtable
* h
, const char *name
, size_t len
)
162 return &h
->h_entries
[fnvhash32(name
, len
) % IDMAP_HASH_SZ
];
165 static struct idmap_hashent
*
166 idmap_lookup_name(struct idmap_hashtable
*h
, const char *name
, size_t len
)
168 struct idmap_hashent
*he
= idmap_name_hash(h
, name
, len
);
170 if (he
->ih_namelen
!= len
|| memcmp(he
->ih_name
, name
, len
) != 0)
172 if (time_after(jiffies
, he
->ih_expires
))
177 static inline struct idmap_hashent
*
178 idmap_id_hash(struct idmap_hashtable
* h
, __u32 id
)
180 return &h
->h_entries
[fnvhash32(&id
, sizeof(id
)) % IDMAP_HASH_SZ
];
183 static struct idmap_hashent
*
184 idmap_lookup_id(struct idmap_hashtable
*h
, __u32 id
)
186 struct idmap_hashent
*he
= idmap_id_hash(h
, id
);
187 if (he
->ih_id
!= id
|| he
->ih_namelen
== 0)
189 if (time_after(jiffies
, he
->ih_expires
))
195 * Routines for allocating new entries in the hashtable.
196 * For now, we just have 1 entry per bucket, so it's all
199 static inline struct idmap_hashent
*
200 idmap_alloc_name(struct idmap_hashtable
*h
, char *name
, unsigned len
)
202 return idmap_name_hash(h
, name
, len
);
205 static inline struct idmap_hashent
*
206 idmap_alloc_id(struct idmap_hashtable
*h
, __u32 id
)
208 return idmap_id_hash(h
, id
);
212 idmap_update_entry(struct idmap_hashent
*he
, const char *name
,
213 size_t namelen
, __u32 id
)
216 memcpy(he
->ih_name
, name
, namelen
);
217 he
->ih_name
[namelen
] = '\0';
218 he
->ih_namelen
= namelen
;
219 he
->ih_expires
= jiffies
+ nfs_idmap_cache_timeout
;
226 nfs_idmap_id(struct idmap
*idmap
, struct idmap_hashtable
*h
,
227 const char *name
, size_t namelen
, __u32
*id
)
229 struct rpc_pipe_msg msg
;
230 struct idmap_msg
*im
;
231 struct idmap_hashent
*he
;
232 DECLARE_WAITQUEUE(wq
, current
);
235 im
= &idmap
->idmap_im
;
238 * String sanity checks
239 * Note that the userland daemon expects NUL terminated strings
244 if (name
[namelen
-1] != '\0')
248 if (namelen
>= IDMAP_NAMESZ
)
251 mutex_lock(&idmap
->idmap_lock
);
252 mutex_lock(&idmap
->idmap_im_lock
);
254 he
= idmap_lookup_name(h
, name
, namelen
);
261 memset(im
, 0, sizeof(*im
));
262 memcpy(im
->im_name
, name
, namelen
);
264 im
->im_type
= h
->h_type
;
265 im
->im_conv
= IDMAP_CONV_NAMETOID
;
267 memset(&msg
, 0, sizeof(msg
));
269 msg
.len
= sizeof(*im
);
271 add_wait_queue(&idmap
->idmap_wq
, &wq
);
272 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
273 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
277 set_current_state(TASK_UNINTERRUPTIBLE
);
278 mutex_unlock(&idmap
->idmap_im_lock
);
280 current
->state
= TASK_RUNNING
;
281 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
282 mutex_lock(&idmap
->idmap_im_lock
);
284 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
290 memset(im
, 0, sizeof(*im
));
291 mutex_unlock(&idmap
->idmap_im_lock
);
292 mutex_unlock(&idmap
->idmap_lock
);
300 nfs_idmap_name(struct idmap
*idmap
, struct idmap_hashtable
*h
,
301 __u32 id
, char *name
)
303 struct rpc_pipe_msg msg
;
304 struct idmap_msg
*im
;
305 struct idmap_hashent
*he
;
306 DECLARE_WAITQUEUE(wq
, current
);
310 im
= &idmap
->idmap_im
;
312 mutex_lock(&idmap
->idmap_lock
);
313 mutex_lock(&idmap
->idmap_im_lock
);
315 he
= idmap_lookup_id(h
, id
);
317 memcpy(name
, he
->ih_name
, he
->ih_namelen
);
318 ret
= he
->ih_namelen
;
322 memset(im
, 0, sizeof(*im
));
323 im
->im_type
= h
->h_type
;
324 im
->im_conv
= IDMAP_CONV_IDTONAME
;
327 memset(&msg
, 0, sizeof(msg
));
329 msg
.len
= sizeof(*im
);
331 add_wait_queue(&idmap
->idmap_wq
, &wq
);
333 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
334 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
338 set_current_state(TASK_UNINTERRUPTIBLE
);
339 mutex_unlock(&idmap
->idmap_im_lock
);
341 current
->state
= TASK_RUNNING
;
342 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
343 mutex_lock(&idmap
->idmap_im_lock
);
345 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
346 if ((len
= strnlen(im
->im_name
, IDMAP_NAMESZ
)) == 0)
348 memcpy(name
, im
->im_name
, len
);
353 memset(im
, 0, sizeof(*im
));
354 mutex_unlock(&idmap
->idmap_im_lock
);
355 mutex_unlock(&idmap
->idmap_lock
);
359 /* RPC pipefs upcall/downcall routines */
361 idmap_pipe_upcall(struct file
*filp
, struct rpc_pipe_msg
*msg
,
362 char __user
*dst
, size_t buflen
)
364 char *data
= (char *)msg
->data
+ msg
->copied
;
365 ssize_t mlen
= msg
->len
- msg
->copied
;
371 left
= copy_to_user(dst
, data
, mlen
);
383 idmap_pipe_downcall(struct file
*filp
, const char __user
*src
, size_t mlen
)
385 struct rpc_inode
*rpci
= RPC_I(filp
->f_dentry
->d_inode
);
386 struct idmap
*idmap
= (struct idmap
*)rpci
->private;
387 struct idmap_msg im_in
, *im
= &idmap
->idmap_im
;
388 struct idmap_hashtable
*h
;
389 struct idmap_hashent
*he
= NULL
;
393 if (mlen
!= sizeof(im_in
))
396 if (copy_from_user(&im_in
, src
, mlen
) != 0)
399 mutex_lock(&idmap
->idmap_im_lock
);
402 im
->im_status
= im_in
.im_status
;
403 /* If we got an error, terminate now, and wake up pending upcalls */
404 if (!(im_in
.im_status
& IDMAP_STATUS_SUCCESS
)) {
405 wake_up(&idmap
->idmap_wq
);
409 /* Sanity checking of strings */
411 namelen_in
= strnlen(im_in
.im_name
, IDMAP_NAMESZ
);
412 if (namelen_in
== 0 || namelen_in
== IDMAP_NAMESZ
)
415 switch (im_in
.im_type
) {
416 case IDMAP_TYPE_USER
:
417 h
= &idmap
->idmap_user_hash
;
419 case IDMAP_TYPE_GROUP
:
420 h
= &idmap
->idmap_group_hash
;
426 switch (im_in
.im_conv
) {
427 case IDMAP_CONV_IDTONAME
:
428 /* Did we match the current upcall? */
429 if (im
->im_conv
== IDMAP_CONV_IDTONAME
430 && im
->im_type
== im_in
.im_type
431 && im
->im_id
== im_in
.im_id
) {
432 /* Yes: copy string, including the terminating '\0' */
433 memcpy(im
->im_name
, im_in
.im_name
, namelen_in
);
434 im
->im_name
[namelen_in
] = '\0';
435 wake_up(&idmap
->idmap_wq
);
437 he
= idmap_alloc_id(h
, im_in
.im_id
);
439 case IDMAP_CONV_NAMETOID
:
440 /* Did we match the current upcall? */
441 if (im
->im_conv
== IDMAP_CONV_NAMETOID
442 && im
->im_type
== im_in
.im_type
443 && strnlen(im
->im_name
, IDMAP_NAMESZ
) == namelen_in
444 && memcmp(im
->im_name
, im_in
.im_name
, namelen_in
) == 0) {
445 im
->im_id
= im_in
.im_id
;
446 wake_up(&idmap
->idmap_wq
);
448 he
= idmap_alloc_name(h
, im_in
.im_name
, namelen_in
);
454 /* If the entry is valid, also copy it to the cache */
456 idmap_update_entry(he
, im_in
.im_name
, namelen_in
, im_in
.im_id
);
459 mutex_unlock(&idmap
->idmap_im_lock
);
464 idmap_pipe_destroy_msg(struct rpc_pipe_msg
*msg
)
466 struct idmap_msg
*im
= msg
->data
;
467 struct idmap
*idmap
= container_of(im
, struct idmap
, idmap_im
);
471 mutex_lock(&idmap
->idmap_im_lock
);
472 im
->im_status
= IDMAP_STATUS_LOOKUPFAIL
;
473 wake_up(&idmap
->idmap_wq
);
474 mutex_unlock(&idmap
->idmap_im_lock
);
478 * Fowler/Noll/Vo hash
479 * http://www.isthe.com/chongo/tech/comp/fnv/
482 #define FNV_P_32 ((unsigned int)0x01000193) /* 16777619 */
483 #define FNV_1_32 ((unsigned int)0x811c9dc5) /* 2166136261 */
485 static unsigned int fnvhash32(const void *buf
, size_t buflen
)
487 const unsigned char *p
, *end
= (const unsigned char *)buf
+ buflen
;
488 unsigned int hash
= FNV_1_32
;
490 for (p
= buf
; p
< end
; p
++) {
492 hash
^= (unsigned int)*p
;
498 int nfs_map_name_to_uid(struct nfs_client
*clp
, const char *name
, size_t namelen
, __u32
*uid
)
500 struct idmap
*idmap
= clp
->cl_idmap
;
502 return nfs_idmap_id(idmap
, &idmap
->idmap_user_hash
, name
, namelen
, uid
);
505 int nfs_map_group_to_gid(struct nfs_client
*clp
, const char *name
, size_t namelen
, __u32
*uid
)
507 struct idmap
*idmap
= clp
->cl_idmap
;
509 return nfs_idmap_id(idmap
, &idmap
->idmap_group_hash
, name
, namelen
, uid
);
512 int nfs_map_uid_to_name(struct nfs_client
*clp
, __u32 uid
, char *buf
)
514 struct idmap
*idmap
= clp
->cl_idmap
;
516 return nfs_idmap_name(idmap
, &idmap
->idmap_user_hash
, uid
, buf
);
518 int nfs_map_gid_to_group(struct nfs_client
*clp
, __u32 uid
, char *buf
)
520 struct idmap
*idmap
= clp
->cl_idmap
;
522 return nfs_idmap_name(idmap
, &idmap
->idmap_group_hash
, uid
, buf
);