Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / fs / nfsd / nfs4idmap.c
blob996bd88b75ba4d4e094129d6e856c561f6843b57
1 /*
2 * fs/nfsd/nfs4idmap.c
4 * Mapping of UID/GIDs to name and vice versa.
6 * Copyright (c) 2002, 2003 The Regents of the University of
7 * Michigan. All rights reserved.
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
13 * are met:
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/init.h>
40 #include <linux/mm.h>
41 #include <linux/utsname.h>
42 #include <linux/errno.h>
43 #include <linux/string.h>
44 #include <linux/sunrpc/clnt.h>
45 #include <linux/nfs.h>
46 #include <linux/nfs4.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/nfs_page.h>
49 #include <linux/sunrpc/cache.h>
50 #include <linux/nfsd_idmap.h>
51 #include <linux/list.h>
52 #include <linux/time.h>
53 #include <linux/seq_file.h>
54 #include <linux/sunrpc/svcauth.h>
57 * Cache entry
61 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
62 * that.
65 #define IDMAP_TYPE_USER 0
66 #define IDMAP_TYPE_GROUP 1
68 struct ent {
69 struct cache_head h;
70 int type; /* User / Group */
71 uid_t id;
72 char name[IDMAP_NAMESZ];
73 char authname[IDMAP_NAMESZ];
76 /* Common entry handling */
78 #define ENT_HASHBITS 8
79 #define ENT_HASHMAX (1 << ENT_HASHBITS)
80 #define ENT_HASHMASK (ENT_HASHMAX - 1)
82 static void
83 ent_init(struct cache_head *cnew, struct cache_head *citm)
85 struct ent *new = container_of(cnew, struct ent, h);
86 struct ent *itm = container_of(citm, struct ent, h);
88 new->id = itm->id;
89 new->type = itm->type;
91 strlcpy(new->name, itm->name, sizeof(new->name));
92 strlcpy(new->authname, itm->authname, sizeof(new->name));
95 static void
96 ent_put(struct kref *ref)
98 struct ent *map = container_of(ref, struct ent, h.ref);
99 kfree(map);
102 static struct cache_head *
103 ent_alloc(void)
105 struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
106 if (e)
107 return &e->h;
108 else
109 return NULL;
113 * ID -> Name cache
116 static struct cache_head *idtoname_table[ENT_HASHMAX];
118 static uint32_t
119 idtoname_hash(struct ent *ent)
121 uint32_t hash;
123 hash = hash_str(ent->authname, ENT_HASHBITS);
124 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
126 /* Flip LSB for user/group */
127 if (ent->type == IDMAP_TYPE_GROUP)
128 hash ^= 1;
130 return hash;
133 static void
134 idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
135 int *blen)
137 struct ent *ent = container_of(ch, struct ent, h);
138 char idstr[11];
140 qword_add(bpp, blen, ent->authname);
141 snprintf(idstr, sizeof(idstr), "%u", ent->id);
142 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
143 qword_add(bpp, blen, idstr);
145 (*bpp)[-1] = '\n';
148 static int
149 idtoname_match(struct cache_head *ca, struct cache_head *cb)
151 struct ent *a = container_of(ca, struct ent, h);
152 struct ent *b = container_of(cb, struct ent, h);
154 return (a->id == b->id && a->type == b->type &&
155 strcmp(a->authname, b->authname) == 0);
158 static int
159 idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
161 struct ent *ent;
163 if (h == NULL) {
164 seq_puts(m, "#domain type id [name]\n");
165 return 0;
167 ent = container_of(h, struct ent, h);
168 seq_printf(m, "%s %s %u", ent->authname,
169 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
170 ent->id);
171 if (test_bit(CACHE_VALID, &h->flags))
172 seq_printf(m, " %s", ent->name);
173 seq_printf(m, "\n");
174 return 0;
177 static void
178 warn_no_idmapd(struct cache_detail *detail)
180 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
181 detail->last_close? "died" : "not been started");
185 static int idtoname_parse(struct cache_detail *, char *, int);
186 static struct ent *idtoname_lookup(struct ent *);
187 static struct ent *idtoname_update(struct ent *, struct ent *);
189 static struct cache_detail idtoname_cache = {
190 .owner = THIS_MODULE,
191 .hash_size = ENT_HASHMAX,
192 .hash_table = idtoname_table,
193 .name = "nfs4.idtoname",
194 .cache_put = ent_put,
195 .cache_request = idtoname_request,
196 .cache_parse = idtoname_parse,
197 .cache_show = idtoname_show,
198 .warn_no_listener = warn_no_idmapd,
199 .match = idtoname_match,
200 .init = ent_init,
201 .update = ent_init,
202 .alloc = ent_alloc,
206 idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
208 struct ent ent, *res;
209 char *buf1, *bp;
210 int len;
211 int error = -EINVAL;
213 if (buf[buflen - 1] != '\n')
214 return (-EINVAL);
215 buf[buflen - 1]= '\0';
217 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
218 if (buf1 == NULL)
219 return (-ENOMEM);
221 memset(&ent, 0, sizeof(ent));
223 /* Authentication name */
224 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
225 goto out;
226 memcpy(ent.authname, buf1, sizeof(ent.authname));
228 /* Type */
229 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
230 goto out;
231 ent.type = strcmp(buf1, "user") == 0 ?
232 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
234 /* ID */
235 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
236 goto out;
237 ent.id = simple_strtoul(buf1, &bp, 10);
238 if (bp == buf1)
239 goto out;
241 /* expiry */
242 ent.h.expiry_time = get_expiry(&buf);
243 if (ent.h.expiry_time == 0)
244 goto out;
246 error = -ENOMEM;
247 res = idtoname_lookup(&ent);
248 if (!res)
249 goto out;
251 /* Name */
252 error = -EINVAL;
253 len = qword_get(&buf, buf1, PAGE_SIZE);
254 if (len < 0)
255 goto out;
256 if (len == 0)
257 set_bit(CACHE_NEGATIVE, &ent.h.flags);
258 else if (len >= IDMAP_NAMESZ)
259 goto out;
260 else
261 memcpy(ent.name, buf1, sizeof(ent.name));
262 error = -ENOMEM;
263 res = idtoname_update(&ent, res);
264 if (res == NULL)
265 goto out;
267 cache_put(&res->h, &idtoname_cache);
269 error = 0;
270 out:
271 kfree(buf1);
273 return error;
277 static struct ent *
278 idtoname_lookup(struct ent *item)
280 struct cache_head *ch = sunrpc_cache_lookup(&idtoname_cache,
281 &item->h,
282 idtoname_hash(item));
283 if (ch)
284 return container_of(ch, struct ent, h);
285 else
286 return NULL;
289 static struct ent *
290 idtoname_update(struct ent *new, struct ent *old)
292 struct cache_head *ch = sunrpc_cache_update(&idtoname_cache,
293 &new->h, &old->h,
294 idtoname_hash(new));
295 if (ch)
296 return container_of(ch, struct ent, h);
297 else
298 return NULL;
303 * Name -> ID cache
306 static struct cache_head *nametoid_table[ENT_HASHMAX];
308 static inline int
309 nametoid_hash(struct ent *ent)
311 return hash_str(ent->name, ENT_HASHBITS);
314 static void
315 nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
316 int *blen)
318 struct ent *ent = container_of(ch, struct ent, h);
320 qword_add(bpp, blen, ent->authname);
321 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
322 qword_add(bpp, blen, ent->name);
324 (*bpp)[-1] = '\n';
327 static int
328 nametoid_match(struct cache_head *ca, struct cache_head *cb)
330 struct ent *a = container_of(ca, struct ent, h);
331 struct ent *b = container_of(cb, struct ent, h);
333 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
334 strcmp(a->authname, b->authname) == 0);
337 static int
338 nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
340 struct ent *ent;
342 if (h == NULL) {
343 seq_puts(m, "#domain type name [id]\n");
344 return 0;
346 ent = container_of(h, struct ent, h);
347 seq_printf(m, "%s %s %s", ent->authname,
348 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
349 ent->name);
350 if (test_bit(CACHE_VALID, &h->flags))
351 seq_printf(m, " %u", ent->id);
352 seq_printf(m, "\n");
353 return 0;
356 static struct ent *nametoid_lookup(struct ent *);
357 static struct ent *nametoid_update(struct ent *, struct ent *);
358 static int nametoid_parse(struct cache_detail *, char *, int);
360 static struct cache_detail nametoid_cache = {
361 .owner = THIS_MODULE,
362 .hash_size = ENT_HASHMAX,
363 .hash_table = nametoid_table,
364 .name = "nfs4.nametoid",
365 .cache_put = ent_put,
366 .cache_request = nametoid_request,
367 .cache_parse = nametoid_parse,
368 .cache_show = nametoid_show,
369 .warn_no_listener = warn_no_idmapd,
370 .match = nametoid_match,
371 .init = ent_init,
372 .update = ent_init,
373 .alloc = ent_alloc,
376 static int
377 nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
379 struct ent ent, *res;
380 char *buf1;
381 int error = -EINVAL;
383 if (buf[buflen - 1] != '\n')
384 return (-EINVAL);
385 buf[buflen - 1]= '\0';
387 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
388 if (buf1 == NULL)
389 return (-ENOMEM);
391 memset(&ent, 0, sizeof(ent));
393 /* Authentication name */
394 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
395 goto out;
396 memcpy(ent.authname, buf1, sizeof(ent.authname));
398 /* Type */
399 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
400 goto out;
401 ent.type = strcmp(buf1, "user") == 0 ?
402 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
404 /* Name */
405 error = qword_get(&buf, buf1, PAGE_SIZE);
406 if (error <= 0 || error >= IDMAP_NAMESZ)
407 goto out;
408 memcpy(ent.name, buf1, sizeof(ent.name));
410 /* expiry */
411 ent.h.expiry_time = get_expiry(&buf);
412 if (ent.h.expiry_time == 0)
413 goto out;
415 /* ID */
416 error = get_int(&buf, &ent.id);
417 if (error == -EINVAL)
418 goto out;
419 if (error == -ENOENT)
420 set_bit(CACHE_NEGATIVE, &ent.h.flags);
422 error = -ENOMEM;
423 res = nametoid_lookup(&ent);
424 if (res == NULL)
425 goto out;
426 res = nametoid_update(&ent, res);
427 if (res == NULL)
428 goto out;
430 cache_put(&res->h, &nametoid_cache);
431 error = 0;
432 out:
433 kfree(buf1);
435 return (error);
439 static struct ent *
440 nametoid_lookup(struct ent *item)
442 struct cache_head *ch = sunrpc_cache_lookup(&nametoid_cache,
443 &item->h,
444 nametoid_hash(item));
445 if (ch)
446 return container_of(ch, struct ent, h);
447 else
448 return NULL;
451 static struct ent *
452 nametoid_update(struct ent *new, struct ent *old)
454 struct cache_head *ch = sunrpc_cache_update(&nametoid_cache,
455 &new->h, &old->h,
456 nametoid_hash(new));
457 if (ch)
458 return container_of(ch, struct ent, h);
459 else
460 return NULL;
464 * Exported API
468 nfsd_idmap_init(void)
470 int rv;
472 rv = cache_register(&idtoname_cache);
473 if (rv)
474 return rv;
475 rv = cache_register(&nametoid_cache);
476 if (rv)
477 cache_unregister(&idtoname_cache);
478 return rv;
481 void
482 nfsd_idmap_shutdown(void)
484 cache_unregister(&idtoname_cache);
485 cache_unregister(&nametoid_cache);
489 * Deferred request handling
492 struct idmap_defer_req {
493 struct cache_req req;
494 struct cache_deferred_req deferred_req;
495 wait_queue_head_t waitq;
496 atomic_t count;
499 static inline void
500 put_mdr(struct idmap_defer_req *mdr)
502 if (atomic_dec_and_test(&mdr->count))
503 kfree(mdr);
506 static inline void
507 get_mdr(struct idmap_defer_req *mdr)
509 atomic_inc(&mdr->count);
512 static void
513 idmap_revisit(struct cache_deferred_req *dreq, int toomany)
515 struct idmap_defer_req *mdr =
516 container_of(dreq, struct idmap_defer_req, deferred_req);
518 wake_up(&mdr->waitq);
519 put_mdr(mdr);
522 static struct cache_deferred_req *
523 idmap_defer(struct cache_req *req)
525 struct idmap_defer_req *mdr =
526 container_of(req, struct idmap_defer_req, req);
528 mdr->deferred_req.revisit = idmap_revisit;
529 get_mdr(mdr);
530 return (&mdr->deferred_req);
533 static inline int
534 do_idmap_lookup(struct ent *(*lookup_fn)(struct ent *), struct ent *key,
535 struct cache_detail *detail, struct ent **item,
536 struct idmap_defer_req *mdr)
538 *item = lookup_fn(key);
539 if (!*item)
540 return -ENOMEM;
541 return cache_check(detail, &(*item)->h, &mdr->req);
544 static inline int
545 do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *),
546 struct ent *key, struct cache_detail *detail,
547 struct ent **item)
549 int ret = -ENOMEM;
551 *item = lookup_fn(key);
552 if (!*item)
553 goto out_err;
554 ret = -ETIMEDOUT;
555 if (!test_bit(CACHE_VALID, &(*item)->h.flags)
556 || (*item)->h.expiry_time < get_seconds()
557 || detail->flush_time > (*item)->h.last_refresh)
558 goto out_put;
559 ret = -ENOENT;
560 if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
561 goto out_put;
562 return 0;
563 out_put:
564 cache_put(&(*item)->h, detail);
565 out_err:
566 *item = NULL;
567 return ret;
570 static int
571 idmap_lookup(struct svc_rqst *rqstp,
572 struct ent *(*lookup_fn)(struct ent *), struct ent *key,
573 struct cache_detail *detail, struct ent **item)
575 struct idmap_defer_req *mdr;
576 int ret;
578 mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
579 if (!mdr)
580 return -ENOMEM;
581 atomic_set(&mdr->count, 1);
582 init_waitqueue_head(&mdr->waitq);
583 mdr->req.defer = idmap_defer;
584 ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
585 if (ret == -EAGAIN) {
586 wait_event_interruptible_timeout(mdr->waitq,
587 test_bit(CACHE_VALID, &(*item)->h.flags), 1 * HZ);
588 ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
590 put_mdr(mdr);
591 return ret;
594 static char *
595 rqst_authname(struct svc_rqst *rqstp)
597 struct auth_domain *clp;
599 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
600 return clp->name;
603 static int
604 idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
605 uid_t *id)
607 struct ent *item, key = {
608 .type = type,
610 int ret;
612 if (namelen + 1 > sizeof(key.name))
613 return -EINVAL;
614 memcpy(key.name, name, namelen);
615 key.name[namelen] = '\0';
616 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
617 ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
618 if (ret == -ENOENT)
619 ret = -ESRCH; /* nfserr_badname */
620 if (ret)
621 return ret;
622 *id = item->id;
623 cache_put(&item->h, &nametoid_cache);
624 return 0;
627 static int
628 idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
630 struct ent *item, key = {
631 .id = id,
632 .type = type,
634 int ret;
636 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
637 ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
638 if (ret == -ENOENT)
639 return sprintf(name, "%u", id);
640 if (ret)
641 return ret;
642 ret = strlen(item->name);
643 BUG_ON(ret > IDMAP_NAMESZ);
644 memcpy(name, item->name, ret);
645 cache_put(&item->h, &idtoname_cache);
646 return ret;
650 nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
651 __u32 *id)
653 return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
657 nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
658 __u32 *id)
660 return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
664 nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
666 return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
670 nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
672 return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);