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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};
69
70/* Common entry handling */
71
72#define ENT_HASHBITS 8
73#define ENT_HASHMAX (1 << ENT_HASHBITS)
74
75static void
76ent_init(struct cache_head *cnew, struct cache_head *citm)
77{
78 struct ent *new = container_of(cnew, struct ent, h);
79 struct ent *itm = container_of(citm, struct ent, h);
80
81 new->id = itm->id;
82 new->type = itm->type;
83
84 strlcpy(new->name, itm->name, sizeof(new->name));
85 strlcpy(new->authname, itm->authname, sizeof(new->name));
86}
87
88static void
89ent_put(struct kref *ref)
90{
91 struct ent *map = container_of(ref, struct ent, h.ref);
92 kfree(map);
93}
94
95static struct cache_head *
96ent_alloc(void)
97{
98 struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
99 if (e)
100 return &e->h;
101 else
102 return NULL;
103}
104
105/*
106 * ID -> Name cache
107 */
108
109static uint32_t
110idtoname_hash(struct ent *ent)
111{
112 uint32_t hash;
113
114 hash = hash_str(ent->authname, ENT_HASHBITS);
115 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
116
117 /* Flip LSB for user/group */
118 if (ent->type == IDMAP_TYPE_GROUP)
119 hash ^= 1;
120
121 return hash;
122}
123
124static void
125idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
126 int *blen)
127{
128 struct ent *ent = container_of(ch, struct ent, h);
129 char idstr[11];
130
131 qword_add(bpp, blen, ent->authname);
132 snprintf(idstr, sizeof(idstr), "%u", ent->id);
133 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
134 qword_add(bpp, blen, idstr);
135
136 (*bpp)[-1] = '\n';
137}
138
139static int
140idtoname_match(struct cache_head *ca, struct cache_head *cb)
141{
142 struct ent *a = container_of(ca, struct ent, h);
143 struct ent *b = container_of(cb, struct ent, h);
144
145 return (a->id == b->id && a->type == b->type &&
146 strcmp(a->authname, b->authname) == 0);
147}
148
149static int
150idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
151{
152 struct ent *ent;
153
154 if (h == NULL) {
155 seq_puts(m, "#domain type id [name]\n");
156 return 0;
157 }
158 ent = container_of(h, struct ent, h);
159 seq_printf(m, "%s %s %u", ent->authname,
160 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
161 ent->id);
162 if (test_bit(CACHE_VALID, &h->flags))
163 seq_printf(m, " %s", ent->name);
164 seq_printf(m, "\n");
165 return 0;
166}
167
168static void
169warn_no_idmapd(struct cache_detail *detail, int has_died)
170{
171 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
172 has_died ? "died" : "not been started");
173}
174
175
176static int idtoname_parse(struct cache_detail *, char *, int);
177static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
178static struct ent *idtoname_update(struct cache_detail *, struct ent *,
179 struct ent *);
180
181static struct cache_detail idtoname_cache_template = {
182 .owner = THIS_MODULE,
183 .hash_size = ENT_HASHMAX,
184 .name = "nfs4.idtoname",
185 .cache_put = ent_put,
186 .cache_request = idtoname_request,
187 .cache_parse = idtoname_parse,
188 .cache_show = idtoname_show,
189 .warn_no_listener = warn_no_idmapd,
190 .match = idtoname_match,
191 .init = ent_init,
192 .update = ent_init,
193 .alloc = ent_alloc,
194};
195
196static int
197idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
198{
199 struct ent ent, *res;
200 char *buf1, *bp;
201 int len;
202 int error = -EINVAL;
203
204 if (buf[buflen - 1] != '\n')
205 return (-EINVAL);
206 buf[buflen - 1]= '\0';
207
208 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
209 if (buf1 == NULL)
210 return (-ENOMEM);
211
212 memset(&ent, 0, sizeof(ent));
213
214 /* Authentication name */
215 len = qword_get(&buf, buf1, PAGE_SIZE);
216 if (len <= 0 || len >= IDMAP_NAMESZ)
217 goto out;
218 memcpy(ent.authname, buf1, sizeof(ent.authname));
219
220 /* Type */
221 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
222 goto out;
223 ent.type = strcmp(buf1, "user") == 0 ?
224 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
225
226 /* ID */
227 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
228 goto out;
229 ent.id = simple_strtoul(buf1, &bp, 10);
230 if (bp == buf1)
231 goto out;
232
233 /* expiry */
234 ent.h.expiry_time = get_expiry(&buf);
235 if (ent.h.expiry_time == 0)
236 goto out;
237
238 error = -ENOMEM;
239 res = idtoname_lookup(cd, &ent);
240 if (!res)
241 goto out;
242
243 /* Name */
244 error = -EINVAL;
245 len = qword_get(&buf, buf1, PAGE_SIZE);
246 if (len < 0 || len >= IDMAP_NAMESZ)
247 goto out;
248 if (len == 0)
249 set_bit(CACHE_NEGATIVE, &ent.h.flags);
250 else
251 memcpy(ent.name, buf1, sizeof(ent.name));
252 error = -ENOMEM;
253 res = idtoname_update(cd, &ent, res);
254 if (res == NULL)
255 goto out;
256
257 cache_put(&res->h, cd);
258 error = 0;
259out:
260 kfree(buf1);
261 return error;
262}
263
264static struct ent *
265idtoname_lookup(struct cache_detail *cd, struct ent *item)
266{
267 struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
268 idtoname_hash(item));
269 if (ch)
270 return container_of(ch, struct ent, h);
271 else
272 return NULL;
273}
274
275static struct ent *
276idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
277{
278 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
279 idtoname_hash(new));
280 if (ch)
281 return container_of(ch, struct ent, h);
282 else
283 return NULL;
284}
285
286
287/*
288 * Name -> ID cache
289 */
290
291static inline int
292nametoid_hash(struct ent *ent)
293{
294 return hash_str(ent->name, ENT_HASHBITS);
295}
296
297static void
298nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
299 int *blen)
300{
301 struct ent *ent = container_of(ch, struct ent, h);
302
303 qword_add(bpp, blen, ent->authname);
304 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
305 qword_add(bpp, blen, ent->name);
306
307 (*bpp)[-1] = '\n';
308}
309
310static int
311nametoid_match(struct cache_head *ca, struct cache_head *cb)
312{
313 struct ent *a = container_of(ca, struct ent, h);
314 struct ent *b = container_of(cb, struct ent, h);
315
316 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
317 strcmp(a->authname, b->authname) == 0);
318}
319
320static int
321nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
322{
323 struct ent *ent;
324
325 if (h == NULL) {
326 seq_puts(m, "#domain type name [id]\n");
327 return 0;
328 }
329 ent = container_of(h, struct ent, h);
330 seq_printf(m, "%s %s %s", ent->authname,
331 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
332 ent->name);
333 if (test_bit(CACHE_VALID, &h->flags))
334 seq_printf(m, " %u", ent->id);
335 seq_printf(m, "\n");
336 return 0;
337}
338
339static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
340static struct ent *nametoid_update(struct cache_detail *, struct ent *,
341 struct ent *);
342static int nametoid_parse(struct cache_detail *, char *, int);
343
344static struct cache_detail nametoid_cache_template = {
345 .owner = THIS_MODULE,
346 .hash_size = ENT_HASHMAX,
347 .name = "nfs4.nametoid",
348 .cache_put = ent_put,
349 .cache_request = nametoid_request,
350 .cache_parse = nametoid_parse,
351 .cache_show = nametoid_show,
352 .warn_no_listener = warn_no_idmapd,
353 .match = nametoid_match,
354 .init = ent_init,
355 .update = ent_init,
356 .alloc = ent_alloc,
357};
358
359static int
360nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
361{
362 struct ent ent, *res;
363 char *buf1;
364 int len, error = -EINVAL;
365
366 if (buf[buflen - 1] != '\n')
367 return (-EINVAL);
368 buf[buflen - 1]= '\0';
369
370 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
371 if (buf1 == NULL)
372 return (-ENOMEM);
373
374 memset(&ent, 0, sizeof(ent));
375
376 /* Authentication name */
377 len = qword_get(&buf, buf1, PAGE_SIZE);
378 if (len <= 0 || len >= IDMAP_NAMESZ)
379 goto out;
380 memcpy(ent.authname, buf1, sizeof(ent.authname));
381
382 /* Type */
383 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
384 goto out;
385 ent.type = strcmp(buf1, "user") == 0 ?
386 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
387
388 /* Name */
389 len = qword_get(&buf, buf1, PAGE_SIZE);
390 if (len <= 0 || len >= IDMAP_NAMESZ)
391 goto out;
392 memcpy(ent.name, buf1, sizeof(ent.name));
393
394 /* expiry */
395 ent.h.expiry_time = get_expiry(&buf);
396 if (ent.h.expiry_time == 0)
397 goto out;
398
399 /* ID */
400 error = get_int(&buf, &ent.id);
401 if (error == -EINVAL)
402 goto out;
403 if (error == -ENOENT)
404 set_bit(CACHE_NEGATIVE, &ent.h.flags);
405
406 error = -ENOMEM;
407 res = nametoid_lookup(cd, &ent);
408 if (res == NULL)
409 goto out;
410 res = nametoid_update(cd, &ent, res);
411 if (res == NULL)
412 goto out;
413
414 cache_put(&res->h, cd);
415 error = 0;
416out:
417 kfree(buf1);
418 return (error);
419}
420
421
422static struct ent *
423nametoid_lookup(struct cache_detail *cd, struct ent *item)
424{
425 struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
426 nametoid_hash(item));
427 if (ch)
428 return container_of(ch, struct ent, h);
429 else
430 return NULL;
431}
432
433static struct ent *
434nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
435{
436 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
437 nametoid_hash(new));
438 if (ch)
439 return container_of(ch, struct ent, h);
440 else
441 return NULL;
442}
443
444/*
445 * Exported API
446 */
447
448int
449nfsd_idmap_init(struct net *net)
450{
451 int rv;
452 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
453
454 nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
455 if (IS_ERR(nn->idtoname_cache))
456 return PTR_ERR(nn->idtoname_cache);
457 rv = cache_register_net(nn->idtoname_cache, net);
458 if (rv)
459 goto destroy_idtoname_cache;
460 nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
461 if (IS_ERR(nn->nametoid_cache)) {
462 rv = PTR_ERR(nn->nametoid_cache);
463 goto unregister_idtoname_cache;
464 }
465 rv = cache_register_net(nn->nametoid_cache, net);
466 if (rv)
467 goto destroy_nametoid_cache;
468 return 0;
469
470destroy_nametoid_cache:
471 cache_destroy_net(nn->nametoid_cache, net);
472unregister_idtoname_cache:
473 cache_unregister_net(nn->idtoname_cache, net);
474destroy_idtoname_cache:
475 cache_destroy_net(nn->idtoname_cache, net);
476 return rv;
477}
478
479void
480nfsd_idmap_shutdown(struct net *net)
481{
482 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
483
484 cache_unregister_net(nn->idtoname_cache, net);
485 cache_unregister_net(nn->nametoid_cache, net);
486 cache_destroy_net(nn->idtoname_cache, net);
487 cache_destroy_net(nn->nametoid_cache, net);
488}
489
490static int
491idmap_lookup(struct svc_rqst *rqstp,
492 struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
493 struct ent *key, struct cache_detail *detail, struct ent **item)
494{
495 int ret;
496
497 *item = lookup_fn(detail, key);
498 if (!*item)
499 return -ENOMEM;
500 retry:
501 ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
502
503 if (ret == -ETIMEDOUT) {
504 struct ent *prev_item = *item;
505 *item = lookup_fn(detail, key);
506 if (*item != prev_item)
507 goto retry;
508 cache_put(&(*item)->h, detail);
509 }
510 return ret;
511}
512
513static char *
514rqst_authname(struct svc_rqst *rqstp)
515{
516 struct auth_domain *clp;
517
518 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
519 return clp->name;
520}
521
522static __be32
523idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
524 u32 *id)
525{
526 struct ent *item, key = {
527 .type = type,
528 };
529 int ret;
530 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
531
532 if (namelen + 1 > sizeof(key.name))
533 return nfserr_badowner;
534 memcpy(key.name, name, namelen);
535 key.name[namelen] = '\0';
536 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
537 ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
538 if (ret == -ENOENT)
539 return nfserr_badowner;
540 if (ret)
541 return nfserrno(ret);
542 *id = item->id;
543 cache_put(&item->h, nn->nametoid_cache);
544 return 0;
545}
546
547static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
548{
549 char buf[11];
550 int len;
551 __be32 *p;
552
553 len = sprintf(buf, "%u", id);
554 p = xdr_reserve_space(xdr, len + 4);
555 if (!p)
556 return nfserr_resource;
557 p = xdr_encode_opaque(p, buf, len);
558 return 0;
559}
560
561static __be32 idmap_id_to_name(struct xdr_stream *xdr,
562 struct svc_rqst *rqstp, int type, u32 id)
563{
564 struct ent *item, key = {
565 .id = id,
566 .type = type,
567 };
568 __be32 *p;
569 int ret;
570 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
571
572 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
573 ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
574 if (ret == -ENOENT)
575 return encode_ascii_id(xdr, id);
576 if (ret)
577 return nfserrno(ret);
578 ret = strlen(item->name);
579 WARN_ON_ONCE(ret > IDMAP_NAMESZ);
580 p = xdr_reserve_space(xdr, ret + 4);
581 if (!p)
582 return nfserr_resource;
583 p = xdr_encode_opaque(p, item->name, ret);
584 cache_put(&item->h, nn->idtoname_cache);
585 return 0;
586}
587
588static bool
589numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
590{
591 int ret;
592 char buf[11];
593
594 if (namelen + 1 > sizeof(buf))
595 /* too long to represent a 32-bit id: */
596 return false;
597 /* Just to make sure it's null-terminated: */
598 memcpy(buf, name, namelen);
599 buf[namelen] = '\0';
600 ret = kstrtouint(buf, 10, id);
601 return ret == 0;
602}
603
604static __be32
605do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
606{
607 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
608 if (numeric_name_to_id(rqstp, type, name, namelen, id))
609 return 0;
610 /*
611 * otherwise, fall through and try idmapping, for
612 * backwards compatibility with clients sending names:
613 */
614 return idmap_name_to_id(rqstp, type, name, namelen, id);
615}
616
617static __be32 encode_name_from_id(struct xdr_stream *xdr,
618 struct svc_rqst *rqstp, int type, u32 id)
619{
620 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
621 return encode_ascii_id(xdr, id);
622 return idmap_id_to_name(xdr, rqstp, type, id);
623}
624
625__be32
626nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
627 kuid_t *uid)
628{
629 __be32 status;
630 u32 id = -1;
631 status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
632 *uid = make_kuid(&init_user_ns, id);
633 if (!uid_valid(*uid))
634 status = nfserr_badowner;
635 return status;
636}
637
638__be32
639nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
640 kgid_t *gid)
641{
642 __be32 status;
643 u32 id = -1;
644 status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
645 *gid = make_kgid(&init_user_ns, id);
646 if (!gid_valid(*gid))
647 status = nfserr_badowner;
648 return status;
649}
650
651__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
652 kuid_t uid)
653{
654 u32 id = from_kuid(&init_user_ns, uid);
655 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
656}
657
658__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
659 kgid_t gid)
660{
661 u32 id = from_kgid(&init_user_ns, gid);
662 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
663}
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}