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 nfs4_client
*clp
)
116 if (clp
->cl_idmap
!= NULL
)
118 if ((idmap
= kzalloc(sizeof(*idmap
), GFP_KERNEL
)) == NULL
)
121 snprintf(idmap
->idmap_path
, sizeof(idmap
->idmap_path
),
122 "%s/idmap", clp
->cl_rpcclient
->cl_pathname
);
124 idmap
->idmap_dentry
= rpc_mkpipe(idmap
->idmap_path
,
125 idmap
, &idmap_upcall_ops
, 0);
126 if (IS_ERR(idmap
->idmap_dentry
)) {
131 mutex_init(&idmap
->idmap_lock
);
132 mutex_init(&idmap
->idmap_im_lock
);
133 init_waitqueue_head(&idmap
->idmap_wq
);
134 idmap
->idmap_user_hash
.h_type
= IDMAP_TYPE_USER
;
135 idmap
->idmap_group_hash
.h_type
= IDMAP_TYPE_GROUP
;
137 clp
->cl_idmap
= idmap
;
141 nfs_idmap_delete(struct nfs4_client
*clp
)
143 struct idmap
*idmap
= clp
->cl_idmap
;
147 rpc_unlink(idmap
->idmap_dentry
);
148 clp
->cl_idmap
= NULL
;
153 * Helper routines for manipulating the hashtable
155 static inline struct idmap_hashent
*
156 idmap_name_hash(struct idmap_hashtable
* h
, const char *name
, size_t len
)
158 return &h
->h_entries
[fnvhash32(name
, len
) % IDMAP_HASH_SZ
];
161 static struct idmap_hashent
*
162 idmap_lookup_name(struct idmap_hashtable
*h
, const char *name
, size_t len
)
164 struct idmap_hashent
*he
= idmap_name_hash(h
, name
, len
);
166 if (he
->ih_namelen
!= len
|| memcmp(he
->ih_name
, name
, len
) != 0)
168 if (time_after(jiffies
, he
->ih_expires
))
173 static inline struct idmap_hashent
*
174 idmap_id_hash(struct idmap_hashtable
* h
, __u32 id
)
176 return &h
->h_entries
[fnvhash32(&id
, sizeof(id
)) % IDMAP_HASH_SZ
];
179 static struct idmap_hashent
*
180 idmap_lookup_id(struct idmap_hashtable
*h
, __u32 id
)
182 struct idmap_hashent
*he
= idmap_id_hash(h
, id
);
183 if (he
->ih_id
!= id
|| he
->ih_namelen
== 0)
185 if (time_after(jiffies
, he
->ih_expires
))
191 * Routines for allocating new entries in the hashtable.
192 * For now, we just have 1 entry per bucket, so it's all
195 static inline struct idmap_hashent
*
196 idmap_alloc_name(struct idmap_hashtable
*h
, char *name
, unsigned len
)
198 return idmap_name_hash(h
, name
, len
);
201 static inline struct idmap_hashent
*
202 idmap_alloc_id(struct idmap_hashtable
*h
, __u32 id
)
204 return idmap_id_hash(h
, id
);
208 idmap_update_entry(struct idmap_hashent
*he
, const char *name
,
209 size_t namelen
, __u32 id
)
212 memcpy(he
->ih_name
, name
, namelen
);
213 he
->ih_name
[namelen
] = '\0';
214 he
->ih_namelen
= namelen
;
215 he
->ih_expires
= jiffies
+ nfs_idmap_cache_timeout
;
222 nfs_idmap_id(struct idmap
*idmap
, struct idmap_hashtable
*h
,
223 const char *name
, size_t namelen
, __u32
*id
)
225 struct rpc_pipe_msg msg
;
226 struct idmap_msg
*im
;
227 struct idmap_hashent
*he
;
228 DECLARE_WAITQUEUE(wq
, current
);
231 im
= &idmap
->idmap_im
;
234 * String sanity checks
235 * Note that the userland daemon expects NUL terminated strings
240 if (name
[namelen
-1] != '\0')
244 if (namelen
>= IDMAP_NAMESZ
)
247 mutex_lock(&idmap
->idmap_lock
);
248 mutex_lock(&idmap
->idmap_im_lock
);
250 he
= idmap_lookup_name(h
, name
, namelen
);
257 memset(im
, 0, sizeof(*im
));
258 memcpy(im
->im_name
, name
, namelen
);
260 im
->im_type
= h
->h_type
;
261 im
->im_conv
= IDMAP_CONV_NAMETOID
;
263 memset(&msg
, 0, sizeof(msg
));
265 msg
.len
= sizeof(*im
);
267 add_wait_queue(&idmap
->idmap_wq
, &wq
);
268 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
269 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
273 set_current_state(TASK_UNINTERRUPTIBLE
);
274 mutex_unlock(&idmap
->idmap_im_lock
);
276 current
->state
= TASK_RUNNING
;
277 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
278 mutex_lock(&idmap
->idmap_im_lock
);
280 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
286 memset(im
, 0, sizeof(*im
));
287 mutex_unlock(&idmap
->idmap_im_lock
);
288 mutex_unlock(&idmap
->idmap_lock
);
296 nfs_idmap_name(struct idmap
*idmap
, struct idmap_hashtable
*h
,
297 __u32 id
, char *name
)
299 struct rpc_pipe_msg msg
;
300 struct idmap_msg
*im
;
301 struct idmap_hashent
*he
;
302 DECLARE_WAITQUEUE(wq
, current
);
306 im
= &idmap
->idmap_im
;
308 mutex_lock(&idmap
->idmap_lock
);
309 mutex_lock(&idmap
->idmap_im_lock
);
311 he
= idmap_lookup_id(h
, id
);
313 memcpy(name
, he
->ih_name
, he
->ih_namelen
);
314 ret
= he
->ih_namelen
;
318 memset(im
, 0, sizeof(*im
));
319 im
->im_type
= h
->h_type
;
320 im
->im_conv
= IDMAP_CONV_IDTONAME
;
323 memset(&msg
, 0, sizeof(msg
));
325 msg
.len
= sizeof(*im
);
327 add_wait_queue(&idmap
->idmap_wq
, &wq
);
329 if (rpc_queue_upcall(idmap
->idmap_dentry
->d_inode
, &msg
) < 0) {
330 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
334 set_current_state(TASK_UNINTERRUPTIBLE
);
335 mutex_unlock(&idmap
->idmap_im_lock
);
337 current
->state
= TASK_RUNNING
;
338 remove_wait_queue(&idmap
->idmap_wq
, &wq
);
339 mutex_lock(&idmap
->idmap_im_lock
);
341 if (im
->im_status
& IDMAP_STATUS_SUCCESS
) {
342 if ((len
= strnlen(im
->im_name
, IDMAP_NAMESZ
)) == 0)
344 memcpy(name
, im
->im_name
, len
);
349 memset(im
, 0, sizeof(*im
));
350 mutex_unlock(&idmap
->idmap_im_lock
);
351 mutex_unlock(&idmap
->idmap_lock
);
355 /* RPC pipefs upcall/downcall routines */
357 idmap_pipe_upcall(struct file
*filp
, struct rpc_pipe_msg
*msg
,
358 char __user
*dst
, size_t buflen
)
360 char *data
= (char *)msg
->data
+ msg
->copied
;
361 ssize_t mlen
= msg
->len
- msg
->copied
;
367 left
= copy_to_user(dst
, data
, mlen
);
379 idmap_pipe_downcall(struct file
*filp
, const char __user
*src
, size_t mlen
)
381 struct rpc_inode
*rpci
= RPC_I(filp
->f_dentry
->d_inode
);
382 struct idmap
*idmap
= (struct idmap
*)rpci
->private;
383 struct idmap_msg im_in
, *im
= &idmap
->idmap_im
;
384 struct idmap_hashtable
*h
;
385 struct idmap_hashent
*he
= NULL
;
389 if (mlen
!= sizeof(im_in
))
392 if (copy_from_user(&im_in
, src
, mlen
) != 0)
395 mutex_lock(&idmap
->idmap_im_lock
);
398 im
->im_status
= im_in
.im_status
;
399 /* If we got an error, terminate now, and wake up pending upcalls */
400 if (!(im_in
.im_status
& IDMAP_STATUS_SUCCESS
)) {
401 wake_up(&idmap
->idmap_wq
);
405 /* Sanity checking of strings */
407 namelen_in
= strnlen(im_in
.im_name
, IDMAP_NAMESZ
);
408 if (namelen_in
== 0 || namelen_in
== IDMAP_NAMESZ
)
411 switch (im_in
.im_type
) {
412 case IDMAP_TYPE_USER
:
413 h
= &idmap
->idmap_user_hash
;
415 case IDMAP_TYPE_GROUP
:
416 h
= &idmap
->idmap_group_hash
;
422 switch (im_in
.im_conv
) {
423 case IDMAP_CONV_IDTONAME
:
424 /* Did we match the current upcall? */
425 if (im
->im_conv
== IDMAP_CONV_IDTONAME
426 && im
->im_type
== im_in
.im_type
427 && im
->im_id
== im_in
.im_id
) {
428 /* Yes: copy string, including the terminating '\0' */
429 memcpy(im
->im_name
, im_in
.im_name
, namelen_in
);
430 im
->im_name
[namelen_in
] = '\0';
431 wake_up(&idmap
->idmap_wq
);
433 he
= idmap_alloc_id(h
, im_in
.im_id
);
435 case IDMAP_CONV_NAMETOID
:
436 /* Did we match the current upcall? */
437 if (im
->im_conv
== IDMAP_CONV_NAMETOID
438 && im
->im_type
== im_in
.im_type
439 && strnlen(im
->im_name
, IDMAP_NAMESZ
) == namelen_in
440 && memcmp(im
->im_name
, im_in
.im_name
, namelen_in
) == 0) {
441 im
->im_id
= im_in
.im_id
;
442 wake_up(&idmap
->idmap_wq
);
444 he
= idmap_alloc_name(h
, im_in
.im_name
, namelen_in
);
450 /* If the entry is valid, also copy it to the cache */
452 idmap_update_entry(he
, im_in
.im_name
, namelen_in
, im_in
.im_id
);
455 mutex_unlock(&idmap
->idmap_im_lock
);
460 idmap_pipe_destroy_msg(struct rpc_pipe_msg
*msg
)
462 struct idmap_msg
*im
= msg
->data
;
463 struct idmap
*idmap
= container_of(im
, struct idmap
, idmap_im
);
467 mutex_lock(&idmap
->idmap_im_lock
);
468 im
->im_status
= IDMAP_STATUS_LOOKUPFAIL
;
469 wake_up(&idmap
->idmap_wq
);
470 mutex_unlock(&idmap
->idmap_im_lock
);
474 * Fowler/Noll/Vo hash
475 * http://www.isthe.com/chongo/tech/comp/fnv/
478 #define FNV_P_32 ((unsigned int)0x01000193) /* 16777619 */
479 #define FNV_1_32 ((unsigned int)0x811c9dc5) /* 2166136261 */
481 static unsigned int fnvhash32(const void *buf
, size_t buflen
)
483 const unsigned char *p
, *end
= (const unsigned char *)buf
+ buflen
;
484 unsigned int hash
= FNV_1_32
;
486 for (p
= buf
; p
< end
; p
++) {
488 hash
^= (unsigned int)*p
;
494 int nfs_map_name_to_uid(struct nfs4_client
*clp
, const char *name
, size_t namelen
, __u32
*uid
)
496 struct idmap
*idmap
= clp
->cl_idmap
;
498 return nfs_idmap_id(idmap
, &idmap
->idmap_user_hash
, name
, namelen
, uid
);
501 int nfs_map_group_to_gid(struct nfs4_client
*clp
, const char *name
, size_t namelen
, __u32
*uid
)
503 struct idmap
*idmap
= clp
->cl_idmap
;
505 return nfs_idmap_id(idmap
, &idmap
->idmap_group_hash
, name
, namelen
, uid
);
508 int nfs_map_uid_to_name(struct nfs4_client
*clp
, __u32 uid
, char *buf
)
510 struct idmap
*idmap
= clp
->cl_idmap
;
512 return nfs_idmap_name(idmap
, &idmap
->idmap_user_hash
, uid
, buf
);
514 int nfs_map_gid_to_group(struct nfs4_client
*clp
, __u32 uid
, char *buf
)
516 struct idmap
*idmap
= clp
->cl_idmap
;
518 return nfs_idmap_name(idmap
, &idmap
->idmap_group_hash
, uid
, buf
);