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 struct idmap_hashent {
61 unsigned long ih_expires;
64 char ih_name[IDMAP_NAMESZ];
67 struct idmap_hashtable {
69 struct idmap_hashent h_entries[IDMAP_HASH_SZ];
74 struct dentry *idmap_dentry;
75 wait_queue_head_t idmap_wq;
76 struct idmap_msg idmap_im;
77 struct mutex idmap_lock; /* Serializes upcalls */
78 struct mutex idmap_im_lock; /* Protects the hashtable */
79 struct idmap_hashtable idmap_user_hash;
80 struct idmap_hashtable idmap_group_hash;
83 static ssize_t idmap_pipe_upcall(struct file *, struct rpc_pipe_msg *,
84 char __user *, size_t);
85 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
87 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
89 static unsigned int fnvhash32(const void *, size_t);
91 static struct rpc_pipe_ops idmap_upcall_ops = {
92 .upcall = idmap_pipe_upcall,
93 .downcall = idmap_pipe_downcall,
94 .destroy_msg = idmap_pipe_destroy_msg,
98 nfs_idmap_new(struct nfs4_client *clp)
102 if (clp->cl_idmap != NULL)
104 if ((idmap = kzalloc(sizeof(*idmap), GFP_KERNEL)) == NULL)
107 snprintf(idmap->idmap_path, sizeof(idmap->idmap_path),
108 "%s/idmap", clp->cl_rpcclient->cl_pathname);
110 idmap->idmap_dentry = rpc_mkpipe(idmap->idmap_path,
111 idmap, &idmap_upcall_ops, 0);
112 if (IS_ERR(idmap->idmap_dentry)) {
117 mutex_init(&idmap->idmap_lock);
118 mutex_init(&idmap->idmap_im_lock);
119 init_waitqueue_head(&idmap->idmap_wq);
120 idmap->idmap_user_hash.h_type = IDMAP_TYPE_USER;
121 idmap->idmap_group_hash.h_type = IDMAP_TYPE_GROUP;
123 clp->cl_idmap = idmap;
127 nfs_idmap_delete(struct nfs4_client *clp)
129 struct idmap *idmap = clp->cl_idmap;
133 rpc_unlink(idmap->idmap_dentry);
134 dput(idmap->idmap_dentry);
135 clp->cl_idmap = NULL;
140 * Helper routines for manipulating the hashtable
142 static inline struct idmap_hashent *
143 idmap_name_hash(struct idmap_hashtable* h, const char *name, size_t len)
145 return &h->h_entries[fnvhash32(name, len) % IDMAP_HASH_SZ];
148 static struct idmap_hashent *
149 idmap_lookup_name(struct idmap_hashtable *h, const char *name, size_t len)
151 struct idmap_hashent *he = idmap_name_hash(h, name, len);
153 if (he->ih_namelen != len || memcmp(he->ih_name, name, len) != 0)
155 if (time_after(jiffies, he->ih_expires))
160 static inline struct idmap_hashent *
161 idmap_id_hash(struct idmap_hashtable* h, __u32 id)
163 return &h->h_entries[fnvhash32(&id, sizeof(id)) % IDMAP_HASH_SZ];
166 static struct idmap_hashent *
167 idmap_lookup_id(struct idmap_hashtable *h, __u32 id)
169 struct idmap_hashent *he = idmap_id_hash(h, id);
170 if (he->ih_id != id || he->ih_namelen == 0)
172 if (time_after(jiffies, he->ih_expires))
178 * Routines for allocating new entries in the hashtable.
179 * For now, we just have 1 entry per bucket, so it's all
182 static inline struct idmap_hashent *
183 idmap_alloc_name(struct idmap_hashtable *h, char *name, unsigned len)
185 return idmap_name_hash(h, name, len);
188 static inline struct idmap_hashent *
189 idmap_alloc_id(struct idmap_hashtable *h, __u32 id)
191 return idmap_id_hash(h, id);
195 idmap_update_entry(struct idmap_hashent *he, const char *name,
196 size_t namelen, __u32 id)
199 memcpy(he->ih_name, name, namelen);
200 he->ih_name[namelen] = '\0';
201 he->ih_namelen = namelen;
202 he->ih_expires = jiffies + nfs_idmap_cache_timeout;
209 nfs_idmap_id(struct idmap *idmap, struct idmap_hashtable *h,
210 const char *name, size_t namelen, __u32 *id)
212 struct rpc_pipe_msg msg;
213 struct idmap_msg *im;
214 struct idmap_hashent *he;
215 DECLARE_WAITQUEUE(wq, current);
218 im = &idmap->idmap_im;
221 * String sanity checks
222 * Note that the userland daemon expects NUL terminated strings
227 if (name[namelen-1] != '\0')
231 if (namelen >= IDMAP_NAMESZ)
234 mutex_lock(&idmap->idmap_lock);
235 mutex_lock(&idmap->idmap_im_lock);
237 he = idmap_lookup_name(h, name, namelen);
244 memset(im, 0, sizeof(*im));
245 memcpy(im->im_name, name, namelen);
247 im->im_type = h->h_type;
248 im->im_conv = IDMAP_CONV_NAMETOID;
250 memset(&msg, 0, sizeof(msg));
252 msg.len = sizeof(*im);
254 add_wait_queue(&idmap->idmap_wq, &wq);
255 if (rpc_queue_upcall(idmap->idmap_dentry->d_inode, &msg) < 0) {
256 remove_wait_queue(&idmap->idmap_wq, &wq);
260 set_current_state(TASK_UNINTERRUPTIBLE);
261 mutex_unlock(&idmap->idmap_im_lock);
263 current->state = TASK_RUNNING;
264 remove_wait_queue(&idmap->idmap_wq, &wq);
265 mutex_lock(&idmap->idmap_im_lock);
267 if (im->im_status & IDMAP_STATUS_SUCCESS) {
273 memset(im, 0, sizeof(*im));
274 mutex_unlock(&idmap->idmap_im_lock);
275 mutex_unlock(&idmap->idmap_lock);
283 nfs_idmap_name(struct idmap *idmap, struct idmap_hashtable *h,
284 __u32 id, char *name)
286 struct rpc_pipe_msg msg;
287 struct idmap_msg *im;
288 struct idmap_hashent *he;
289 DECLARE_WAITQUEUE(wq, current);
293 im = &idmap->idmap_im;
295 mutex_lock(&idmap->idmap_lock);
296 mutex_lock(&idmap->idmap_im_lock);
298 he = idmap_lookup_id(h, id);
300 memcpy(name, he->ih_name, he->ih_namelen);
301 ret = he->ih_namelen;
305 memset(im, 0, sizeof(*im));
306 im->im_type = h->h_type;
307 im->im_conv = IDMAP_CONV_IDTONAME;
310 memset(&msg, 0, sizeof(msg));
312 msg.len = sizeof(*im);
314 add_wait_queue(&idmap->idmap_wq, &wq);
316 if (rpc_queue_upcall(idmap->idmap_dentry->d_inode, &msg) < 0) {
317 remove_wait_queue(&idmap->idmap_wq, &wq);
321 set_current_state(TASK_UNINTERRUPTIBLE);
322 mutex_unlock(&idmap->idmap_im_lock);
324 current->state = TASK_RUNNING;
325 remove_wait_queue(&idmap->idmap_wq, &wq);
326 mutex_lock(&idmap->idmap_im_lock);
328 if (im->im_status & IDMAP_STATUS_SUCCESS) {
329 if ((len = strnlen(im->im_name, IDMAP_NAMESZ)) == 0)
331 memcpy(name, im->im_name, len);
336 memset(im, 0, sizeof(*im));
337 mutex_unlock(&idmap->idmap_im_lock);
338 mutex_unlock(&idmap->idmap_lock);
342 /* RPC pipefs upcall/downcall routines */
344 idmap_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
345 char __user *dst, size_t buflen)
347 char *data = (char *)msg->data + msg->copied;
348 ssize_t mlen = msg->len - msg->copied;
354 left = copy_to_user(dst, data, mlen);
366 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
368 struct rpc_inode *rpci = RPC_I(filp->f_dentry->d_inode);
369 struct idmap *idmap = (struct idmap *)rpci->private;
370 struct idmap_msg im_in, *im = &idmap->idmap_im;
371 struct idmap_hashtable *h;
372 struct idmap_hashent *he = NULL;
376 if (mlen != sizeof(im_in))
379 if (copy_from_user(&im_in, src, mlen) != 0)
382 mutex_lock(&idmap->idmap_im_lock);
385 im->im_status = im_in.im_status;
386 /* If we got an error, terminate now, and wake up pending upcalls */
387 if (!(im_in.im_status & IDMAP_STATUS_SUCCESS)) {
388 wake_up(&idmap->idmap_wq);
392 /* Sanity checking of strings */
394 namelen_in = strnlen(im_in.im_name, IDMAP_NAMESZ);
395 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ)
398 switch (im_in.im_type) {
399 case IDMAP_TYPE_USER:
400 h = &idmap->idmap_user_hash;
402 case IDMAP_TYPE_GROUP:
403 h = &idmap->idmap_group_hash;
409 switch (im_in.im_conv) {
410 case IDMAP_CONV_IDTONAME:
411 /* Did we match the current upcall? */
412 if (im->im_conv == IDMAP_CONV_IDTONAME
413 && im->im_type == im_in.im_type
414 && im->im_id == im_in.im_id) {
415 /* Yes: copy string, including the terminating '\0' */
416 memcpy(im->im_name, im_in.im_name, namelen_in);
417 im->im_name[namelen_in] = '\0';
418 wake_up(&idmap->idmap_wq);
420 he = idmap_alloc_id(h, im_in.im_id);
422 case IDMAP_CONV_NAMETOID:
423 /* Did we match the current upcall? */
424 if (im->im_conv == IDMAP_CONV_NAMETOID
425 && im->im_type == im_in.im_type
426 && strnlen(im->im_name, IDMAP_NAMESZ) == namelen_in
427 && memcmp(im->im_name, im_in.im_name, namelen_in) == 0) {
428 im->im_id = im_in.im_id;
429 wake_up(&idmap->idmap_wq);
431 he = idmap_alloc_name(h, im_in.im_name, namelen_in);
437 /* If the entry is valid, also copy it to the cache */
439 idmap_update_entry(he, im_in.im_name, namelen_in, im_in.im_id);
442 mutex_unlock(&idmap->idmap_im_lock);
447 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
449 struct idmap_msg *im = msg->data;
450 struct idmap *idmap = container_of(im, struct idmap, idmap_im);
454 mutex_lock(&idmap->idmap_im_lock);
455 im->im_status = IDMAP_STATUS_LOOKUPFAIL;
456 wake_up(&idmap->idmap_wq);
457 mutex_unlock(&idmap->idmap_im_lock);
461 * Fowler/Noll/Vo hash
462 * http://www.isthe.com/chongo/tech/comp/fnv/
465 #define FNV_P_32 ((unsigned int)0x01000193) /* 16777619 */
466 #define FNV_1_32 ((unsigned int)0x811c9dc5) /* 2166136261 */
468 static unsigned int fnvhash32(const void *buf, size_t buflen)
470 const unsigned char *p, *end = (const unsigned char *)buf + buflen;
471 unsigned int hash = FNV_1_32;
473 for (p = buf; p < end; p++) {
475 hash ^= (unsigned int)*p;
481 int nfs_map_name_to_uid(struct nfs4_client *clp, const char *name, size_t namelen, __u32 *uid)
483 struct idmap *idmap = clp->cl_idmap;
485 return nfs_idmap_id(idmap, &idmap->idmap_user_hash, name, namelen, uid);
488 int nfs_map_group_to_gid(struct nfs4_client *clp, const char *name, size_t namelen, __u32 *uid)
490 struct idmap *idmap = clp->cl_idmap;
492 return nfs_idmap_id(idmap, &idmap->idmap_group_hash, name, namelen, uid);
495 int nfs_map_uid_to_name(struct nfs4_client *clp, __u32 uid, char *buf)
497 struct idmap *idmap = clp->cl_idmap;
499 return nfs_idmap_name(idmap, &idmap->idmap_user_hash, uid, buf);
501 int nfs_map_gid_to_group(struct nfs4_client *clp, __u32 uid, char *buf)
503 struct idmap *idmap = clp->cl_idmap;
505 return nfs_idmap_name(idmap, &idmap->idmap_group_hash, uid, buf);