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1/*
2 * Mapping of UID/GIDs to name and vice versa.
3 *
4 * Copyright (c) 2002, 2003 The Regents of the University of
5 * Michigan. All rights reserved.
6 *
7 * Marius Aamodt Eriksen <marius@umich.edu>
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35#include <linux/module.h>
36#include <linux/seq_file.h>
37#include <linux/sched.h>
38#include <linux/slab.h>
39#include <linux/sunrpc/svc_xprt.h>
40#include <net/net_namespace.h>
41#include "idmap.h"
42#include "nfsd.h"
43#include "netns.h"
44
45/*
46 * Turn off idmapping when using AUTH_SYS.
47 */
48static bool nfs4_disable_idmapping = true;
49module_param(nfs4_disable_idmapping, bool, 0644);
50MODULE_PARM_DESC(nfs4_disable_idmapping,
51 "Turn off server's NFSv4 idmapping when using 'sec=sys'");
52
53/*
54 * Cache entry
55 */
56
57/*
58 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
59 * that.
60 */
61
62struct ent {
63 struct cache_head h;
64 int type; /* User / Group */
65 u32 id;
66 char name[IDMAP_NAMESZ];
67 char authname[IDMAP_NAMESZ];
68 struct rcu_head rcu_head;
69};
70
71/* Common entry handling */
72
73#define ENT_HASHBITS 8
74#define ENT_HASHMAX (1 << ENT_HASHBITS)
75
76static void
77ent_init(struct cache_head *cnew, struct cache_head *citm)
78{
79 struct ent *new = container_of(cnew, struct ent, h);
80 struct ent *itm = container_of(citm, struct ent, h);
81
82 new->id = itm->id;
83 new->type = itm->type;
84
85 strlcpy(new->name, itm->name, sizeof(new->name));
86 strlcpy(new->authname, itm->authname, sizeof(new->authname));
87}
88
89static void
90ent_put(struct kref *ref)
91{
92 struct ent *map = container_of(ref, struct ent, h.ref);
93 kfree_rcu(map, rcu_head);
94}
95
96static struct cache_head *
97ent_alloc(void)
98{
99 struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
100 if (e)
101 return &e->h;
102 else
103 return NULL;
104}
105
106/*
107 * ID -> Name cache
108 */
109
110static uint32_t
111idtoname_hash(struct ent *ent)
112{
113 uint32_t hash;
114
115 hash = hash_str(ent->authname, ENT_HASHBITS);
116 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
117
118 /* Flip LSB for user/group */
119 if (ent->type == IDMAP_TYPE_GROUP)
120 hash ^= 1;
121
122 return hash;
123}
124
125static void
126idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
127 int *blen)
128{
129 struct ent *ent = container_of(ch, struct ent, h);
130 char idstr[11];
131
132 qword_add(bpp, blen, ent->authname);
133 snprintf(idstr, sizeof(idstr), "%u", ent->id);
134 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
135 qword_add(bpp, blen, idstr);
136
137 (*bpp)[-1] = '\n';
138}
139
140static int
141idtoname_match(struct cache_head *ca, struct cache_head *cb)
142{
143 struct ent *a = container_of(ca, struct ent, h);
144 struct ent *b = container_of(cb, struct ent, h);
145
146 return (a->id == b->id && a->type == b->type &&
147 strcmp(a->authname, b->authname) == 0);
148}
149
150static int
151idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
152{
153 struct ent *ent;
154
155 if (h == NULL) {
156 seq_puts(m, "#domain type id [name]\n");
157 return 0;
158 }
159 ent = container_of(h, struct ent, h);
160 seq_printf(m, "%s %s %u", ent->authname,
161 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
162 ent->id);
163 if (test_bit(CACHE_VALID, &h->flags))
164 seq_printf(m, " %s", ent->name);
165 seq_printf(m, "\n");
166 return 0;
167}
168
169static void
170warn_no_idmapd(struct cache_detail *detail, int has_died)
171{
172 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
173 has_died ? "died" : "not been started");
174}
175
176
177static int idtoname_parse(struct cache_detail *, char *, int);
178static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
179static struct ent *idtoname_update(struct cache_detail *, struct ent *,
180 struct ent *);
181
182static const struct cache_detail idtoname_cache_template = {
183 .owner = THIS_MODULE,
184 .hash_size = ENT_HASHMAX,
185 .name = "nfs4.idtoname",
186 .cache_put = ent_put,
187 .cache_request = idtoname_request,
188 .cache_parse = idtoname_parse,
189 .cache_show = idtoname_show,
190 .warn_no_listener = warn_no_idmapd,
191 .match = idtoname_match,
192 .init = ent_init,
193 .update = ent_init,
194 .alloc = ent_alloc,
195};
196
197static int
198idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
199{
200 struct ent ent, *res;
201 char *buf1, *bp;
202 int len;
203 int error = -EINVAL;
204
205 if (buf[buflen - 1] != '\n')
206 return (-EINVAL);
207 buf[buflen - 1]= '\0';
208
209 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
210 if (buf1 == NULL)
211 return (-ENOMEM);
212
213 memset(&ent, 0, sizeof(ent));
214
215 /* Authentication name */
216 len = qword_get(&buf, buf1, PAGE_SIZE);
217 if (len <= 0 || len >= IDMAP_NAMESZ)
218 goto out;
219 memcpy(ent.authname, buf1, sizeof(ent.authname));
220
221 /* Type */
222 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
223 goto out;
224 ent.type = strcmp(buf1, "user") == 0 ?
225 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
226
227 /* ID */
228 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
229 goto out;
230 ent.id = simple_strtoul(buf1, &bp, 10);
231 if (bp == buf1)
232 goto out;
233
234 /* expiry */
235 ent.h.expiry_time = get_expiry(&buf);
236 if (ent.h.expiry_time == 0)
237 goto out;
238
239 error = -ENOMEM;
240 res = idtoname_lookup(cd, &ent);
241 if (!res)
242 goto out;
243
244 /* Name */
245 error = -EINVAL;
246 len = qword_get(&buf, buf1, PAGE_SIZE);
247 if (len < 0 || len >= IDMAP_NAMESZ)
248 goto out;
249 if (len == 0)
250 set_bit(CACHE_NEGATIVE, &ent.h.flags);
251 else
252 memcpy(ent.name, buf1, sizeof(ent.name));
253 error = -ENOMEM;
254 res = idtoname_update(cd, &ent, res);
255 if (res == NULL)
256 goto out;
257
258 cache_put(&res->h, cd);
259 error = 0;
260out:
261 kfree(buf1);
262 return error;
263}
264
265static struct ent *
266idtoname_lookup(struct cache_detail *cd, struct ent *item)
267{
268 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
269 idtoname_hash(item));
270 if (ch)
271 return container_of(ch, struct ent, h);
272 else
273 return NULL;
274}
275
276static struct ent *
277idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
278{
279 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
280 idtoname_hash(new));
281 if (ch)
282 return container_of(ch, struct ent, h);
283 else
284 return NULL;
285}
286
287
288/*
289 * Name -> ID cache
290 */
291
292static inline int
293nametoid_hash(struct ent *ent)
294{
295 return hash_str(ent->name, ENT_HASHBITS);
296}
297
298static void
299nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
300 int *blen)
301{
302 struct ent *ent = container_of(ch, struct ent, h);
303
304 qword_add(bpp, blen, ent->authname);
305 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
306 qword_add(bpp, blen, ent->name);
307
308 (*bpp)[-1] = '\n';
309}
310
311static int
312nametoid_match(struct cache_head *ca, struct cache_head *cb)
313{
314 struct ent *a = container_of(ca, struct ent, h);
315 struct ent *b = container_of(cb, struct ent, h);
316
317 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
318 strcmp(a->authname, b->authname) == 0);
319}
320
321static int
322nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
323{
324 struct ent *ent;
325
326 if (h == NULL) {
327 seq_puts(m, "#domain type name [id]\n");
328 return 0;
329 }
330 ent = container_of(h, struct ent, h);
331 seq_printf(m, "%s %s %s", ent->authname,
332 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
333 ent->name);
334 if (test_bit(CACHE_VALID, &h->flags))
335 seq_printf(m, " %u", ent->id);
336 seq_printf(m, "\n");
337 return 0;
338}
339
340static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
341static struct ent *nametoid_update(struct cache_detail *, struct ent *,
342 struct ent *);
343static int nametoid_parse(struct cache_detail *, char *, int);
344
345static const struct cache_detail nametoid_cache_template = {
346 .owner = THIS_MODULE,
347 .hash_size = ENT_HASHMAX,
348 .name = "nfs4.nametoid",
349 .cache_put = ent_put,
350 .cache_request = nametoid_request,
351 .cache_parse = nametoid_parse,
352 .cache_show = nametoid_show,
353 .warn_no_listener = warn_no_idmapd,
354 .match = nametoid_match,
355 .init = ent_init,
356 .update = ent_init,
357 .alloc = ent_alloc,
358};
359
360static int
361nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
362{
363 struct ent ent, *res;
364 char *buf1;
365 int len, error = -EINVAL;
366
367 if (buf[buflen - 1] != '\n')
368 return (-EINVAL);
369 buf[buflen - 1]= '\0';
370
371 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
372 if (buf1 == NULL)
373 return (-ENOMEM);
374
375 memset(&ent, 0, sizeof(ent));
376
377 /* Authentication name */
378 len = qword_get(&buf, buf1, PAGE_SIZE);
379 if (len <= 0 || len >= IDMAP_NAMESZ)
380 goto out;
381 memcpy(ent.authname, buf1, sizeof(ent.authname));
382
383 /* Type */
384 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
385 goto out;
386 ent.type = strcmp(buf1, "user") == 0 ?
387 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
388
389 /* Name */
390 len = qword_get(&buf, buf1, PAGE_SIZE);
391 if (len <= 0 || len >= IDMAP_NAMESZ)
392 goto out;
393 memcpy(ent.name, buf1, sizeof(ent.name));
394
395 /* expiry */
396 ent.h.expiry_time = get_expiry(&buf);
397 if (ent.h.expiry_time == 0)
398 goto out;
399
400 /* ID */
401 error = get_int(&buf, &ent.id);
402 if (error == -EINVAL)
403 goto out;
404 if (error == -ENOENT)
405 set_bit(CACHE_NEGATIVE, &ent.h.flags);
406
407 error = -ENOMEM;
408 res = nametoid_lookup(cd, &ent);
409 if (res == NULL)
410 goto out;
411 res = nametoid_update(cd, &ent, res);
412 if (res == NULL)
413 goto out;
414
415 cache_put(&res->h, cd);
416 error = 0;
417out:
418 kfree(buf1);
419 return (error);
420}
421
422
423static struct ent *
424nametoid_lookup(struct cache_detail *cd, struct ent *item)
425{
426 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
427 nametoid_hash(item));
428 if (ch)
429 return container_of(ch, struct ent, h);
430 else
431 return NULL;
432}
433
434static struct ent *
435nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
436{
437 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
438 nametoid_hash(new));
439 if (ch)
440 return container_of(ch, struct ent, h);
441 else
442 return NULL;
443}
444
445/*
446 * Exported API
447 */
448
449int
450nfsd_idmap_init(struct net *net)
451{
452 int rv;
453 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
454
455 nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
456 if (IS_ERR(nn->idtoname_cache))
457 return PTR_ERR(nn->idtoname_cache);
458 rv = cache_register_net(nn->idtoname_cache, net);
459 if (rv)
460 goto destroy_idtoname_cache;
461 nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
462 if (IS_ERR(nn->nametoid_cache)) {
463 rv = PTR_ERR(nn->nametoid_cache);
464 goto unregister_idtoname_cache;
465 }
466 rv = cache_register_net(nn->nametoid_cache, net);
467 if (rv)
468 goto destroy_nametoid_cache;
469 return 0;
470
471destroy_nametoid_cache:
472 cache_destroy_net(nn->nametoid_cache, net);
473unregister_idtoname_cache:
474 cache_unregister_net(nn->idtoname_cache, net);
475destroy_idtoname_cache:
476 cache_destroy_net(nn->idtoname_cache, net);
477 return rv;
478}
479
480void
481nfsd_idmap_shutdown(struct net *net)
482{
483 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
484
485 cache_unregister_net(nn->idtoname_cache, net);
486 cache_unregister_net(nn->nametoid_cache, net);
487 cache_destroy_net(nn->idtoname_cache, net);
488 cache_destroy_net(nn->nametoid_cache, net);
489}
490
491static int
492idmap_lookup(struct svc_rqst *rqstp,
493 struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
494 struct ent *key, struct cache_detail *detail, struct ent **item)
495{
496 int ret;
497
498 *item = lookup_fn(detail, key);
499 if (!*item)
500 return -ENOMEM;
501 retry:
502 ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
503
504 if (ret == -ETIMEDOUT) {
505 struct ent *prev_item = *item;
506 *item = lookup_fn(detail, key);
507 if (*item != prev_item)
508 goto retry;
509 cache_put(&(*item)->h, detail);
510 }
511 return ret;
512}
513
514static char *
515rqst_authname(struct svc_rqst *rqstp)
516{
517 struct auth_domain *clp;
518
519 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
520 return clp->name;
521}
522
523static __be32
524idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
525 u32 *id)
526{
527 struct ent *item, key = {
528 .type = type,
529 };
530 int ret;
531 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
532
533 if (namelen + 1 > sizeof(key.name))
534 return nfserr_badowner;
535 memcpy(key.name, name, namelen);
536 key.name[namelen] = '\0';
537 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
538 ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
539 if (ret == -ENOENT)
540 return nfserr_badowner;
541 if (ret)
542 return nfserrno(ret);
543 *id = item->id;
544 cache_put(&item->h, nn->nametoid_cache);
545 return 0;
546}
547
548static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
549{
550 char buf[11];
551 int len;
552 __be32 *p;
553
554 len = sprintf(buf, "%u", id);
555 p = xdr_reserve_space(xdr, len + 4);
556 if (!p)
557 return nfserr_resource;
558 p = xdr_encode_opaque(p, buf, len);
559 return 0;
560}
561
562static __be32 idmap_id_to_name(struct xdr_stream *xdr,
563 struct svc_rqst *rqstp, int type, u32 id)
564{
565 struct ent *item, key = {
566 .id = id,
567 .type = type,
568 };
569 __be32 *p;
570 int ret;
571 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
572
573 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
574 ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
575 if (ret == -ENOENT)
576 return encode_ascii_id(xdr, id);
577 if (ret)
578 return nfserrno(ret);
579 ret = strlen(item->name);
580 WARN_ON_ONCE(ret > IDMAP_NAMESZ);
581 p = xdr_reserve_space(xdr, ret + 4);
582 if (!p)
583 return nfserr_resource;
584 p = xdr_encode_opaque(p, item->name, ret);
585 cache_put(&item->h, nn->idtoname_cache);
586 return 0;
587}
588
589static bool
590numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
591{
592 int ret;
593 char buf[11];
594
595 if (namelen + 1 > sizeof(buf))
596 /* too long to represent a 32-bit id: */
597 return false;
598 /* Just to make sure it's null-terminated: */
599 memcpy(buf, name, namelen);
600 buf[namelen] = '\0';
601 ret = kstrtouint(buf, 10, id);
602 return ret == 0;
603}
604
605static __be32
606do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
607{
608 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
609 if (numeric_name_to_id(rqstp, type, name, namelen, id))
610 return 0;
611 /*
612 * otherwise, fall through and try idmapping, for
613 * backwards compatibility with clients sending names:
614 */
615 return idmap_name_to_id(rqstp, type, name, namelen, id);
616}
617
618static __be32 encode_name_from_id(struct xdr_stream *xdr,
619 struct svc_rqst *rqstp, int type, u32 id)
620{
621 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
622 return encode_ascii_id(xdr, id);
623 return idmap_id_to_name(xdr, rqstp, type, id);
624}
625
626__be32
627nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
628 kuid_t *uid)
629{
630 __be32 status;
631 u32 id = -1;
632
633 if (name == NULL || namelen == 0)
634 return nfserr_inval;
635
636 status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
637 *uid = make_kuid(nfsd_user_namespace(rqstp), id);
638 if (!uid_valid(*uid))
639 status = nfserr_badowner;
640 return status;
641}
642
643__be32
644nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
645 kgid_t *gid)
646{
647 __be32 status;
648 u32 id = -1;
649
650 if (name == NULL || namelen == 0)
651 return nfserr_inval;
652
653 status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
654 *gid = make_kgid(nfsd_user_namespace(rqstp), id);
655 if (!gid_valid(*gid))
656 status = nfserr_badowner;
657 return status;
658}
659
660__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
661 kuid_t uid)
662{
663 u32 id = from_kuid_munged(nfsd_user_namespace(rqstp), uid);
664 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
665}
666
667__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
668 kgid_t gid)
669{
670 u32 id = from_kgid_munged(nfsd_user_namespace(rqstp), gid);
671 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
672}
1/*
2 * Mapping of UID/GIDs to name and vice versa.
3 *
4 * Copyright (c) 2002, 2003 The Regents of the University of
5 * Michigan. All rights reserved.
6 *
7 * Marius Aamodt Eriksen <marius@umich.edu>
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35#include <linux/module.h>
36#include <linux/seq_file.h>
37#include <linux/sched.h>
38#include <linux/slab.h>
39#include <linux/sunrpc/svc_xprt.h>
40#include <net/net_namespace.h>
41#include "idmap.h"
42#include "nfsd.h"
43#include "netns.h"
44#include "vfs.h"
45
46/*
47 * Turn off idmapping when using AUTH_SYS.
48 */
49static bool nfs4_disable_idmapping = true;
50module_param(nfs4_disable_idmapping, bool, 0644);
51MODULE_PARM_DESC(nfs4_disable_idmapping,
52 "Turn off server's NFSv4 idmapping when using 'sec=sys'");
53
54/*
55 * Cache entry
56 */
57
58/*
59 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
60 * that.
61 */
62
63struct ent {
64 struct cache_head h;
65 int type; /* User / Group */
66 u32 id;
67 char name[IDMAP_NAMESZ];
68 char authname[IDMAP_NAMESZ];
69 struct rcu_head rcu_head;
70};
71
72/* Common entry handling */
73
74#define ENT_HASHBITS 8
75#define ENT_HASHMAX (1 << ENT_HASHBITS)
76
77static void
78ent_init(struct cache_head *cnew, struct cache_head *citm)
79{
80 struct ent *new = container_of(cnew, struct ent, h);
81 struct ent *itm = container_of(citm, struct ent, h);
82
83 new->id = itm->id;
84 new->type = itm->type;
85
86 strscpy(new->name, itm->name, sizeof(new->name));
87 strscpy(new->authname, itm->authname, sizeof(new->authname));
88}
89
90static void
91ent_put(struct kref *ref)
92{
93 struct ent *map = container_of(ref, struct ent, h.ref);
94 kfree_rcu(map, rcu_head);
95}
96
97static struct cache_head *
98ent_alloc(void)
99{
100 struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
101 if (e)
102 return &e->h;
103 else
104 return NULL;
105}
106
107/*
108 * ID -> Name cache
109 */
110
111static uint32_t
112idtoname_hash(struct ent *ent)
113{
114 uint32_t hash;
115
116 hash = hash_str(ent->authname, ENT_HASHBITS);
117 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
118
119 /* Flip LSB for user/group */
120 if (ent->type == IDMAP_TYPE_GROUP)
121 hash ^= 1;
122
123 return hash;
124}
125
126static int
127idtoname_upcall(struct cache_detail *cd, struct cache_head *h)
128{
129 return sunrpc_cache_pipe_upcall_timeout(cd, h);
130}
131
132static void
133idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
134 int *blen)
135{
136 struct ent *ent = container_of(ch, struct ent, h);
137 char idstr[11];
138
139 qword_add(bpp, blen, ent->authname);
140 snprintf(idstr, sizeof(idstr), "%u", ent->id);
141 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
142 qword_add(bpp, blen, idstr);
143
144 (*bpp)[-1] = '\n';
145}
146
147static int
148idtoname_match(struct cache_head *ca, struct cache_head *cb)
149{
150 struct ent *a = container_of(ca, struct ent, h);
151 struct ent *b = container_of(cb, struct ent, h);
152
153 return (a->id == b->id && a->type == b->type &&
154 strcmp(a->authname, b->authname) == 0);
155}
156
157static int
158idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
159{
160 struct ent *ent;
161
162 if (h == NULL) {
163 seq_puts(m, "#domain type id [name]\n");
164 return 0;
165 }
166 ent = container_of(h, struct ent, h);
167 seq_printf(m, "%s %s %u", ent->authname,
168 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
169 ent->id);
170 if (test_bit(CACHE_VALID, &h->flags))
171 seq_printf(m, " %s", ent->name);
172 seq_putc(m, '\n');
173 return 0;
174}
175
176static void
177warn_no_idmapd(struct cache_detail *detail, int has_died)
178{
179 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
180 has_died ? "died" : "not been started");
181}
182
183
184static int idtoname_parse(struct cache_detail *, char *, int);
185static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
186static struct ent *idtoname_update(struct cache_detail *, struct ent *,
187 struct ent *);
188
189static const struct cache_detail idtoname_cache_template = {
190 .owner = THIS_MODULE,
191 .hash_size = ENT_HASHMAX,
192 .name = "nfs4.idtoname",
193 .cache_put = ent_put,
194 .cache_upcall = idtoname_upcall,
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,
203};
204
205static int
206idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
207{
208 struct ent ent, *res;
209 char *buf1, *bp;
210 int len;
211 int error = -EINVAL;
212
213 if (buf[buflen - 1] != '\n')
214 return (-EINVAL);
215 buf[buflen - 1]= '\0';
216
217 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
218 if (buf1 == NULL)
219 return (-ENOMEM);
220
221 memset(&ent, 0, sizeof(ent));
222
223 /* Authentication name */
224 len = qword_get(&buf, buf1, PAGE_SIZE);
225 if (len <= 0 || len >= IDMAP_NAMESZ)
226 goto out;
227 memcpy(ent.authname, buf1, sizeof(ent.authname));
228
229 /* Type */
230 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
231 goto out;
232 ent.type = strcmp(buf1, "user") == 0 ?
233 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
234
235 /* ID */
236 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
237 goto out;
238 ent.id = simple_strtoul(buf1, &bp, 10);
239 if (bp == buf1)
240 goto out;
241
242 /* expiry */
243 error = get_expiry(&buf, &ent.h.expiry_time);
244 if (error)
245 goto out;
246
247 error = -ENOMEM;
248 res = idtoname_lookup(cd, &ent);
249 if (!res)
250 goto out;
251
252 /* Name */
253 error = -EINVAL;
254 len = qword_get(&buf, buf1, PAGE_SIZE);
255 if (len < 0 || len >= IDMAP_NAMESZ)
256 goto out;
257 if (len == 0)
258 set_bit(CACHE_NEGATIVE, &ent.h.flags);
259 else
260 memcpy(ent.name, buf1, sizeof(ent.name));
261 error = -ENOMEM;
262 res = idtoname_update(cd, &ent, res);
263 if (res == NULL)
264 goto out;
265
266 cache_put(&res->h, cd);
267 error = 0;
268out:
269 kfree(buf1);
270 return error;
271}
272
273static struct ent *
274idtoname_lookup(struct cache_detail *cd, struct ent *item)
275{
276 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
277 idtoname_hash(item));
278 if (ch)
279 return container_of(ch, struct ent, h);
280 else
281 return NULL;
282}
283
284static struct ent *
285idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
286{
287 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
288 idtoname_hash(new));
289 if (ch)
290 return container_of(ch, struct ent, h);
291 else
292 return NULL;
293}
294
295
296/*
297 * Name -> ID cache
298 */
299
300static inline int
301nametoid_hash(struct ent *ent)
302{
303 return hash_str(ent->name, ENT_HASHBITS);
304}
305
306static int
307nametoid_upcall(struct cache_detail *cd, struct cache_head *h)
308{
309 return sunrpc_cache_pipe_upcall_timeout(cd, h);
310}
311
312static void
313nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
314 int *blen)
315{
316 struct ent *ent = container_of(ch, struct ent, h);
317
318 qword_add(bpp, blen, ent->authname);
319 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
320 qword_add(bpp, blen, ent->name);
321
322 (*bpp)[-1] = '\n';
323}
324
325static int
326nametoid_match(struct cache_head *ca, struct cache_head *cb)
327{
328 struct ent *a = container_of(ca, struct ent, h);
329 struct ent *b = container_of(cb, struct ent, h);
330
331 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
332 strcmp(a->authname, b->authname) == 0);
333}
334
335static int
336nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
337{
338 struct ent *ent;
339
340 if (h == NULL) {
341 seq_puts(m, "#domain type name [id]\n");
342 return 0;
343 }
344 ent = container_of(h, struct ent, h);
345 seq_printf(m, "%s %s %s", ent->authname,
346 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
347 ent->name);
348 if (test_bit(CACHE_VALID, &h->flags))
349 seq_printf(m, " %u", ent->id);
350 seq_putc(m, '\n');
351 return 0;
352}
353
354static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
355static struct ent *nametoid_update(struct cache_detail *, struct ent *,
356 struct ent *);
357static int nametoid_parse(struct cache_detail *, char *, int);
358
359static const struct cache_detail nametoid_cache_template = {
360 .owner = THIS_MODULE,
361 .hash_size = ENT_HASHMAX,
362 .name = "nfs4.nametoid",
363 .cache_put = ent_put,
364 .cache_upcall = nametoid_upcall,
365 .cache_request = nametoid_request,
366 .cache_parse = nametoid_parse,
367 .cache_show = nametoid_show,
368 .warn_no_listener = warn_no_idmapd,
369 .match = nametoid_match,
370 .init = ent_init,
371 .update = ent_init,
372 .alloc = ent_alloc,
373};
374
375static int
376nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
377{
378 struct ent ent, *res;
379 char *buf1;
380 int len, error = -EINVAL;
381
382 if (buf[buflen - 1] != '\n')
383 return (-EINVAL);
384 buf[buflen - 1]= '\0';
385
386 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
387 if (buf1 == NULL)
388 return (-ENOMEM);
389
390 memset(&ent, 0, sizeof(ent));
391
392 /* Authentication name */
393 len = qword_get(&buf, buf1, PAGE_SIZE);
394 if (len <= 0 || len >= IDMAP_NAMESZ)
395 goto out;
396 memcpy(ent.authname, buf1, sizeof(ent.authname));
397
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;
403
404 /* Name */
405 len = qword_get(&buf, buf1, PAGE_SIZE);
406 if (len <= 0 || len >= IDMAP_NAMESZ)
407 goto out;
408 memcpy(ent.name, buf1, sizeof(ent.name));
409
410 /* expiry */
411 error = get_expiry(&buf, &ent.h.expiry_time);
412 if (error)
413 goto out;
414
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);
421
422 error = -ENOMEM;
423 res = nametoid_lookup(cd, &ent);
424 if (res == NULL)
425 goto out;
426 res = nametoid_update(cd, &ent, res);
427 if (res == NULL)
428 goto out;
429
430 cache_put(&res->h, cd);
431 error = 0;
432out:
433 kfree(buf1);
434 return (error);
435}
436
437
438static struct ent *
439nametoid_lookup(struct cache_detail *cd, struct ent *item)
440{
441 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
442 nametoid_hash(item));
443 if (ch)
444 return container_of(ch, struct ent, h);
445 else
446 return NULL;
447}
448
449static struct ent *
450nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
451{
452 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
453 nametoid_hash(new));
454 if (ch)
455 return container_of(ch, struct ent, h);
456 else
457 return NULL;
458}
459
460/*
461 * Exported API
462 */
463
464int
465nfsd_idmap_init(struct net *net)
466{
467 int rv;
468 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
469
470 nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
471 if (IS_ERR(nn->idtoname_cache))
472 return PTR_ERR(nn->idtoname_cache);
473 rv = cache_register_net(nn->idtoname_cache, net);
474 if (rv)
475 goto destroy_idtoname_cache;
476 nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
477 if (IS_ERR(nn->nametoid_cache)) {
478 rv = PTR_ERR(nn->nametoid_cache);
479 goto unregister_idtoname_cache;
480 }
481 rv = cache_register_net(nn->nametoid_cache, net);
482 if (rv)
483 goto destroy_nametoid_cache;
484 return 0;
485
486destroy_nametoid_cache:
487 cache_destroy_net(nn->nametoid_cache, net);
488unregister_idtoname_cache:
489 cache_unregister_net(nn->idtoname_cache, net);
490destroy_idtoname_cache:
491 cache_destroy_net(nn->idtoname_cache, net);
492 return rv;
493}
494
495void
496nfsd_idmap_shutdown(struct net *net)
497{
498 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
499
500 cache_unregister_net(nn->idtoname_cache, net);
501 cache_unregister_net(nn->nametoid_cache, net);
502 cache_destroy_net(nn->idtoname_cache, net);
503 cache_destroy_net(nn->nametoid_cache, net);
504}
505
506static int
507idmap_lookup(struct svc_rqst *rqstp,
508 struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
509 struct ent *key, struct cache_detail *detail, struct ent **item)
510{
511 int ret;
512
513 *item = lookup_fn(detail, key);
514 if (!*item)
515 return -ENOMEM;
516 retry:
517 ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
518
519 if (ret == -ETIMEDOUT) {
520 struct ent *prev_item = *item;
521 *item = lookup_fn(detail, key);
522 if (*item != prev_item)
523 goto retry;
524 cache_put(&(*item)->h, detail);
525 }
526 return ret;
527}
528
529static char *
530rqst_authname(struct svc_rqst *rqstp)
531{
532 struct auth_domain *clp;
533
534 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
535 return clp->name;
536}
537
538static __be32
539idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
540 u32 *id)
541{
542 struct ent *item, key = {
543 .type = type,
544 };
545 int ret;
546 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
547
548 if (namelen + 1 > sizeof(key.name))
549 return nfserr_badowner;
550 memcpy(key.name, name, namelen);
551 key.name[namelen] = '\0';
552 strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
553 ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
554 if (ret == -ENOENT)
555 return nfserr_badowner;
556 if (ret)
557 return nfserrno(ret);
558 *id = item->id;
559 cache_put(&item->h, nn->nametoid_cache);
560 return 0;
561}
562
563static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
564{
565 char buf[11];
566 int len;
567 __be32 *p;
568
569 len = sprintf(buf, "%u", id);
570 p = xdr_reserve_space(xdr, len + 4);
571 if (!p)
572 return nfserr_resource;
573 p = xdr_encode_opaque(p, buf, len);
574 return 0;
575}
576
577static __be32 idmap_id_to_name(struct xdr_stream *xdr,
578 struct svc_rqst *rqstp, int type, u32 id)
579{
580 struct ent *item, key = {
581 .id = id,
582 .type = type,
583 };
584 __be32 *p;
585 int ret;
586 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
587
588 strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
589 ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
590 if (ret == -ENOENT)
591 return encode_ascii_id(xdr, id);
592 if (ret)
593 return nfserrno(ret);
594 ret = strlen(item->name);
595 WARN_ON_ONCE(ret > IDMAP_NAMESZ);
596 p = xdr_reserve_space(xdr, ret + 4);
597 if (!p)
598 return nfserr_resource;
599 p = xdr_encode_opaque(p, item->name, ret);
600 cache_put(&item->h, nn->idtoname_cache);
601 return 0;
602}
603
604static bool
605numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
606{
607 int ret;
608 char buf[11];
609
610 if (namelen + 1 > sizeof(buf))
611 /* too long to represent a 32-bit id: */
612 return false;
613 /* Just to make sure it's null-terminated: */
614 memcpy(buf, name, namelen);
615 buf[namelen] = '\0';
616 ret = kstrtouint(buf, 10, id);
617 return ret == 0;
618}
619
620static __be32
621do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
622{
623 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
624 if (numeric_name_to_id(rqstp, type, name, namelen, id))
625 return 0;
626 /*
627 * otherwise, fall through and try idmapping, for
628 * backwards compatibility with clients sending names:
629 */
630 return idmap_name_to_id(rqstp, type, name, namelen, id);
631}
632
633static __be32 encode_name_from_id(struct xdr_stream *xdr,
634 struct svc_rqst *rqstp, int type, u32 id)
635{
636 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
637 return encode_ascii_id(xdr, id);
638 return idmap_id_to_name(xdr, rqstp, type, id);
639}
640
641__be32
642nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
643 kuid_t *uid)
644{
645 __be32 status;
646 u32 id = -1;
647
648 if (name == NULL || namelen == 0)
649 return nfserr_inval;
650
651 status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
652 *uid = make_kuid(nfsd_user_namespace(rqstp), id);
653 if (!uid_valid(*uid))
654 status = nfserr_badowner;
655 return status;
656}
657
658__be32
659nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
660 kgid_t *gid)
661{
662 __be32 status;
663 u32 id = -1;
664
665 if (name == NULL || namelen == 0)
666 return nfserr_inval;
667
668 status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
669 *gid = make_kgid(nfsd_user_namespace(rqstp), id);
670 if (!gid_valid(*gid))
671 status = nfserr_badowner;
672 return status;
673}
674
675__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
676 kuid_t uid)
677{
678 u32 id = from_kuid_munged(nfsd_user_namespace(rqstp), uid);
679 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
680}
681
682__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
683 kgid_t gid)
684{
685 u32 id = from_kgid_munged(nfsd_user_namespace(rqstp), gid);
686 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
687}